1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 // SPDX-License-Identifier: GPL-2.0+ /* * Belkin USB Serial Adapter Driver * * Copyright (C) 2000 William Greathouse (wgreathouse@smva.com) * Copyright (C) 2000-2001 Greg Kroah-Hartman (greg@kroah.com) * Copyright (C) 2010 Johan Hovold (jhovold@gmail.com) * * This program is largely derived from work by the linux-usb group * and associated source files. Please see the usb/serial files for * individual credits and copyrights. * * See Documentation/usb/usb-serial.rst for more information on using this * driver * * TODO: * -- Add true modem control line query capability. Currently we track the * states reported by the interrupt and the states we request. * -- Add support for flush commands */ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/tty.h> #include <linux/tty_driver.h> #include <linux/tty_flip.h> #include <linux/module.h> #include <linux/spinlock.h> #include <linux/uaccess.h> #include <linux/usb.h> #include <linux/usb/serial.h> #include "belkin_sa.h" #define DRIVER_AUTHOR "William Greathouse <wgreathouse@smva.com>" #define DRIVER_DESC "USB Belkin Serial converter driver" /* function prototypes for a Belkin USB Serial Adapter F5U103 */ static int belkin_sa_port_probe(struct usb_serial_port *port); static void belkin_sa_port_remove(struct usb_serial_port *port); static int belkin_sa_open(struct tty_struct *tty, struct usb_serial_port *port); static void belkin_sa_close(struct usb_serial_port *port); static void belkin_sa_read_int_callback(struct urb *urb); static void belkin_sa_process_read_urb(struct urb *urb); static void belkin_sa_set_termios(struct tty_struct *tty, struct usb_serial_port *port, const struct ktermios *old_termios); static int belkin_sa_break_ctl(struct tty_struct *tty, int break_state); static int belkin_sa_tiocmget(struct tty_struct *tty); static int belkin_sa_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear); static const struct usb_device_id id_table[] = { { USB_DEVICE(BELKIN_SA_VID, BELKIN_SA_PID) }, { USB_DEVICE(BELKIN_OLD_VID, BELKIN_OLD_PID) }, { USB_DEVICE(PERACOM_VID, PERACOM_PID) }, { USB_DEVICE(GOHUBS_VID, GOHUBS_PID) }, { USB_DEVICE(GOHUBS_VID, HANDYLINK_PID) }, { USB_DEVICE(BELKIN_DOCKSTATION_VID, BELKIN_DOCKSTATION_PID) }, { } /* Terminating entry */ }; MODULE_DEVICE_TABLE(usb, id_table); /* All of the device info needed for the serial converters */ static struct usb_serial_driver belkin_device = { .driver = { .owner = THIS_MODULE, .name = "belkin", }, .description = "Belkin / Peracom / GoHubs USB Serial Adapter", .id_table = id_table, .num_ports = 1, .open = belkin_sa_open, .close = belkin_sa_close, .read_int_callback = belkin_sa_read_int_callback, .process_read_urb = belkin_sa_process_read_urb, .set_termios = belkin_sa_set_termios, .break_ctl = belkin_sa_break_ctl, .tiocmget = belkin_sa_tiocmget, .tiocmset = belkin_sa_tiocmset, .port_probe = belkin_sa_port_probe, .port_remove = belkin_sa_port_remove, }; static struct usb_serial_driver * const serial_drivers[] = { &belkin_device, NULL }; struct belkin_sa_private { spinlock_t lock; unsigned long control_state; unsigned char last_lsr; unsigned char last_msr; int bad_flow_control; }; /* * *************************************************************************** * Belkin USB Serial Adapter F5U103 specific driver functions * *************************************************************************** */ #define WDR_TIMEOUT 5000 /* default urb timeout */ /* assumes that struct usb_serial *serial is available */ #define BSA_USB_CMD(c, v) usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), \ (c), BELKIN_SA_SET_REQUEST_TYPE, \ (v), 0, NULL, 0, WDR_TIMEOUT) static int belkin_sa_port_probe(struct usb_serial_port *port) { struct usb_device *dev = port->serial->dev; struct belkin_sa_private *priv; priv = kmalloc(sizeof(struct belkin_sa_private), GFP_KERNEL); if (!priv) return -ENOMEM; spin_lock_init(&priv->lock); priv->control_state = 0; priv->last_lsr = 0; priv->last_msr = 0; /* see comments at top of file */ priv->bad_flow_control = (le16_to_cpu(dev->descriptor.bcdDevice) <= 0x0206) ? 1 : 0; dev_info(&dev->dev, "bcdDevice: %04x, bfc: %d\n", le16_to_cpu(dev->descriptor.bcdDevice), priv->bad_flow_control); usb_set_serial_port_data(port, priv); return 0; } static void belkin_sa_port_remove(struct usb_serial_port *port) { struct belkin_sa_private *priv; priv = usb_get_serial_port_data(port); kfree(priv); } static int belkin_sa_open(struct tty_struct *tty, struct usb_serial_port *port) { int retval; retval = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); if (retval) { dev_err(&port->dev, "usb_submit_urb(read int) failed\n"); return retval; } retval = usb_serial_generic_open(tty, port); if (retval) usb_kill_urb(port->interrupt_in_urb); return retval; } static void belkin_sa_close(struct usb_serial_port *port) { usb_serial_generic_close(port); usb_kill_urb(port->interrupt_in_urb); } static void belkin_sa_read_int_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; struct belkin_sa_private *priv; unsigned char *data = urb->transfer_buffer; int retval; int status = urb->status; unsigned long flags; switch (status) { case 0: /* success */ break; case -ECONNRESET: case -ENOENT: case -ESHUTDOWN: /* this urb is terminated, clean up */ dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n", __func__, status); return; default: dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n", __func__, status); goto exit; } usb_serial_debug_data(&port->dev, __func__, urb->actual_length, data); /* Handle known interrupt data */ /* ignore data[0] and data[1] */ priv = usb_get_serial_port_data(port); spin_lock_irqsave(&priv->lock, flags); priv->last_msr = data[BELKIN_SA_MSR_INDEX]; /* Record Control Line states */ if (priv->last_msr & BELKIN_SA_MSR_DSR) priv->control_state |= TIOCM_DSR; else priv->control_state &= ~TIOCM_DSR; if (priv->last_msr & BELKIN_SA_MSR_CTS) priv->control_state |= TIOCM_CTS; else priv->control_state &= ~TIOCM_CTS; if (priv->last_msr & BELKIN_SA_MSR_RI) priv->control_state |= TIOCM_RI; else priv->control_state &= ~TIOCM_RI; if (priv->last_msr & BELKIN_SA_MSR_CD) priv->control_state |= TIOCM_CD; else priv->control_state &= ~TIOCM_CD; priv->last_lsr = data[BELKIN_SA_LSR_INDEX]; spin_unlock_irqrestore(&priv->lock, flags); exit: retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval) dev_err(&port->dev, "%s - usb_submit_urb failed with " "result %d\n", __func__, retval); } static void belkin_sa_process_read_urb(struct urb *urb) { struct usb_serial_port *port = urb->context; struct belkin_sa_private *priv = usb_get_serial_port_data(port); unsigned char *data = urb->transfer_buffer; unsigned long flags; unsigned char status; char tty_flag; /* Update line status */ tty_flag = TTY_NORMAL; spin_lock_irqsave(&priv->lock, flags); status = priv->last_lsr; priv->last_lsr &= ~BELKIN_SA_LSR_ERR; spin_unlock_irqrestore(&priv->lock, flags); if (!urb->actual_length) return; if (status & BELKIN_SA_LSR_ERR) { /* Break takes precedence over parity, which takes precedence * over framing errors. */ if (status & BELKIN_SA_LSR_BI) tty_flag = TTY_BREAK; else if (status & BELKIN_SA_LSR_PE) tty_flag = TTY_PARITY; else if (status & BELKIN_SA_LSR_FE) tty_flag = TTY_FRAME; dev_dbg(&port->dev, "tty_flag = %d\n", tty_flag); /* Overrun is special, not associated with a char. */ if (status & BELKIN_SA_LSR_OE) tty_insert_flip_char(&port->port, 0, TTY_OVERRUN); } tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag, urb->actual_length); tty_flip_buffer_push(&port->port); } static void belkin_sa_set_termios(struct tty_struct *tty, struct usb_serial_port *port, const struct ktermios *old_termios) { struct usb_serial *serial = port->serial; struct belkin_sa_private *priv = usb_get_serial_port_data(port); unsigned int iflag; unsigned int cflag; unsigned int old_iflag = 0; unsigned int old_cflag = 0; __u16 urb_value = 0; /* Will hold the new flags */ unsigned long flags; unsigned long control_state; int bad_flow_control; speed_t baud; struct ktermios *termios = &tty->termios; iflag = termios->c_iflag; cflag = termios->c_cflag; termios->c_cflag &= ~CMSPAR; /* get a local copy of the current port settings */ spin_lock_irqsave(&priv->lock, flags); control_state = priv->control_state; bad_flow_control = priv->bad_flow_control; spin_unlock_irqrestore(&priv->lock, flags); old_iflag = old_termios->c_iflag; old_cflag = old_termios->c_cflag; /* Set the baud rate */ if ((cflag & CBAUD) != (old_cflag & CBAUD)) { /* reassert DTR and (maybe) RTS on transition from B0 */ if ((old_cflag & CBAUD) == B0) { control_state |= (TIOCM_DTR|TIOCM_RTS); if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 1) < 0) dev_err(&port->dev, "Set DTR error\n"); /* don't set RTS if using hardware flow control */ if (!(old_cflag & CRTSCTS)) if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST , 1) < 0) dev_err(&port->dev, "Set RTS error\n"); } } baud = tty_get_baud_rate(tty); if (baud) { urb_value = BELKIN_SA_BAUD(baud); /* Clip to maximum speed */ if (urb_value == 0) urb_value = 1; /* Turn it back into a resulting real baud rate */ baud = BELKIN_SA_BAUD(urb_value); /* Report the actual baud rate back to the caller */ tty_encode_baud_rate(tty, baud, baud); if (BSA_USB_CMD(BELKIN_SA_SET_BAUDRATE_REQUEST, urb_value) < 0) dev_err(&port->dev, "Set baudrate error\n"); } else { /* Disable flow control */ if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, BELKIN_SA_FLOW_NONE) < 0) dev_err(&port->dev, "Disable flowcontrol error\n"); /* Drop RTS and DTR */ control_state &= ~(TIOCM_DTR | TIOCM_RTS); if (BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, 0) < 0) dev_err(&port->dev, "DTR LOW error\n"); if (BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, 0) < 0) dev_err(&port->dev, "RTS LOW error\n"); } /* set the parity */ if ((cflag ^ old_cflag) & (PARENB | PARODD)) { if (cflag & PARENB) urb_value = (cflag & PARODD) ? BELKIN_SA_PARITY_ODD : BELKIN_SA_PARITY_EVEN; else urb_value = BELKIN_SA_PARITY_NONE; if (BSA_USB_CMD(BELKIN_SA_SET_PARITY_REQUEST, urb_value) < 0) dev_err(&port->dev, "Set parity error\n"); } /* set the number of data bits */ if ((cflag & CSIZE) != (old_cflag & CSIZE)) { urb_value = BELKIN_SA_DATA_BITS(tty_get_char_size(cflag)); if (BSA_USB_CMD(BELKIN_SA_SET_DATA_BITS_REQUEST, urb_value) < 0) dev_err(&port->dev, "Set data bits error\n"); } /* set the number of stop bits */ if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) { urb_value = (cflag & CSTOPB) ? BELKIN_SA_STOP_BITS(2) : BELKIN_SA_STOP_BITS(1); if (BSA_USB_CMD(BELKIN_SA_SET_STOP_BITS_REQUEST, urb_value) < 0) dev_err(&port->dev, "Set stop bits error\n"); } /* Set flow control */ if (((iflag ^ old_iflag) & (IXOFF | IXON)) || ((cflag ^ old_cflag) & CRTSCTS)) { urb_value = 0; if ((iflag & IXOFF) || (iflag & IXON)) urb_value |= (BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON); else urb_value &= ~(BELKIN_SA_FLOW_OXON | BELKIN_SA_FLOW_IXON); if (cflag & CRTSCTS) urb_value |= (BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS); else urb_value &= ~(BELKIN_SA_FLOW_OCTS | BELKIN_SA_FLOW_IRTS); if (bad_flow_control) urb_value &= ~(BELKIN_SA_FLOW_IRTS); if (BSA_USB_CMD(BELKIN_SA_SET_FLOW_CTRL_REQUEST, urb_value) < 0) dev_err(&port->dev, "Set flow control error\n"); } /* save off the modified port settings */ spin_lock_irqsave(&priv->lock, flags); priv->control_state = control_state; spin_unlock_irqrestore(&priv->lock, flags); } static int belkin_sa_break_ctl(struct tty_struct *tty, int break_state) { struct usb_serial_port *port = tty->driver_data; struct usb_serial *serial = port->serial; int ret; ret = BSA_USB_CMD(BELKIN_SA_SET_BREAK_REQUEST, break_state ? 1 : 0); if (ret < 0) { dev_err(&port->dev, "Set break_ctl %d\n", break_state); return ret; } return 0; } static int belkin_sa_tiocmget(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct belkin_sa_private *priv = usb_get_serial_port_data(port); unsigned long control_state; unsigned long flags; spin_lock_irqsave(&priv->lock, flags); control_state = priv->control_state; spin_unlock_irqrestore(&priv->lock, flags); return control_state; } static int belkin_sa_tiocmset(struct tty_struct *tty, unsigned int set, unsigned int clear) { struct usb_serial_port *port = tty->driver_data; struct usb_serial *serial = port->serial; struct belkin_sa_private *priv = usb_get_serial_port_data(port); unsigned long control_state; unsigned long flags; int retval; int rts = 0; int dtr = 0; spin_lock_irqsave(&priv->lock, flags); control_state = priv->control_state; if (set & TIOCM_RTS) { control_state |= TIOCM_RTS; rts = 1; } if (set & TIOCM_DTR) { control_state |= TIOCM_DTR; dtr = 1; } if (clear & TIOCM_RTS) { control_state &= ~TIOCM_RTS; rts = 0; } if (clear & TIOCM_DTR) { control_state &= ~TIOCM_DTR; dtr = 0; } priv->control_state = control_state; spin_unlock_irqrestore(&priv->lock, flags); retval = BSA_USB_CMD(BELKIN_SA_SET_RTS_REQUEST, rts); if (retval < 0) { dev_err(&port->dev, "Set RTS error %d\n", retval); goto exit; } retval = BSA_USB_CMD(BELKIN_SA_SET_DTR_REQUEST, dtr); if (retval < 0) { dev_err(&port->dev, "Set DTR error %d\n", retval); goto exit; } exit: return retval; } module_usb_serial_driver(serial_drivers, id_table); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL");
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 /* SPDX-License-Identifier: GPL-2.0-only */ /* * Access to user system call parameters and results * * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved. * * See asm-generic/syscall.h for descriptions of what we must do here. */ #ifndef _ASM_X86_SYSCALL_H #define _ASM_X86_SYSCALL_H #include <uapi/linux/audit.h> #include <linux/sched.h> #include <linux/err.h> #include <asm/thread_info.h> /* for TS_COMPAT */ #include <asm/unistd.h> /* This is used purely for kernel/trace/trace_syscalls.c */ typedef long (*sys_call_ptr_t)(const struct pt_regs *); extern const sys_call_ptr_t sys_call_table[]; /* * These may not exist, but still put the prototypes in so we * can use IS_ENABLED(). */ extern long ia32_sys_call(const struct pt_regs *, unsigned int nr); extern long x32_sys_call(const struct pt_regs *, unsigned int nr); extern long x64_sys_call(const struct pt_regs *, unsigned int nr); /* * Only the low 32 bits of orig_ax are meaningful, so we return int. * This importantly ignores the high bits on 64-bit, so comparisons * sign-extend the low 32 bits. */ static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) { return regs->orig_ax; } static inline void syscall_rollback(struct task_struct *task, struct pt_regs *regs) { regs->ax = regs->orig_ax; } static inline long syscall_get_error(struct task_struct *task, struct pt_regs *regs) { unsigned long error = regs->ax; #ifdef CONFIG_IA32_EMULATION /* * TS_COMPAT is set for 32-bit syscall entries and then * remains set until we return to user mode. */ if (task->thread_info.status & (TS_COMPAT|TS_I386_REGS_POKED)) /* * Sign-extend the value so (int)-EFOO becomes (long)-EFOO * and will match correctly in comparisons. */ error = (long) (int) error; #endif return IS_ERR_VALUE(error) ? error : 0; } static inline long syscall_get_return_value(struct task_struct *task, struct pt_regs *regs) { return regs->ax; } static inline void syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, int error, long val) { regs->ax = (long) error ?: val; } #ifdef CONFIG_X86_32 static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, unsigned long *args) { memcpy(args, &regs->bx, 6 * sizeof(args[0])); } static inline int syscall_get_arch(struct task_struct *task) { return AUDIT_ARCH_I386; } #else /* CONFIG_X86_64 */ static inline void syscall_get_arguments(struct task_struct *task, struct pt_regs *regs, unsigned long *args) { # ifdef CONFIG_IA32_EMULATION if (task->thread_info.status & TS_COMPAT) { *args++ = regs->bx; *args++ = regs->cx; *args++ = regs->dx; *args++ = regs->si; *args++ = regs->di; *args = regs->bp; } else # endif { *args++ = regs->di; *args++ = regs->si; *args++ = regs->dx; *args++ = regs->r10; *args++ = regs->r8; *args = regs->r9; } } static inline int syscall_get_arch(struct task_struct *task) { /* x32 tasks should be considered AUDIT_ARCH_X86_64. */ return (IS_ENABLED(CONFIG_IA32_EMULATION) && task->thread_info.status & TS_COMPAT) ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64; } bool do_syscall_64(struct pt_regs *regs, int nr); void do_int80_emulation(struct pt_regs *regs); #endif /* CONFIG_X86_32 */ void do_int80_syscall_32(struct pt_regs *regs); bool do_fast_syscall_32(struct pt_regs *regs); bool do_SYSENTER_32(struct pt_regs *regs); #endif /* _ASM_X86_SYSCALL_H */
7 7 5 7 7 6 28 2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 // SPDX-License-Identifier: GPL-2.0-only /* * lib/bitmap.c * Helper functions for bitmap.h. */ #include <linux/bitmap.h> #include <linux/bitops.h> #include <linux/ctype.h> #include <linux/device.h> #include <linux/export.h> #include <linux/slab.h> /** * DOC: bitmap introduction * * bitmaps provide an array of bits, implemented using an * array of unsigned longs. The number of valid bits in a * given bitmap does _not_ need to be an exact multiple of * BITS_PER_LONG. * * The possible unused bits in the last, partially used word * of a bitmap are 'don't care'. The implementation makes * no particular effort to keep them zero. It ensures that * their value will not affect the results of any operation. * The bitmap operations that return Boolean (bitmap_empty, * for example) or scalar (bitmap_weight, for example) results * carefully filter out these unused bits from impacting their * results. * * The byte ordering of bitmaps is more natural on little * endian architectures. See the big-endian headers * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h * for the best explanations of this ordering. */ bool __bitmap_equal(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k, lim = bits/BITS_PER_LONG; for (k = 0; k < lim; ++k) if (bitmap1[k] != bitmap2[k]) return false; if (bits % BITS_PER_LONG) if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) return false; return true; } EXPORT_SYMBOL(__bitmap_equal); bool __bitmap_or_equal(const unsigned long *bitmap1, const unsigned long *bitmap2, const unsigned long *bitmap3, unsigned int bits) { unsigned int k, lim = bits / BITS_PER_LONG; unsigned long tmp; for (k = 0; k < lim; ++k) { if ((bitmap1[k] | bitmap2[k]) != bitmap3[k]) return false; } if (!(bits % BITS_PER_LONG)) return true; tmp = (bitmap1[k] | bitmap2[k]) ^ bitmap3[k]; return (tmp & BITMAP_LAST_WORD_MASK(bits)) == 0; } void __bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int bits) { unsigned int k, lim = BITS_TO_LONGS(bits); for (k = 0; k < lim; ++k) dst[k] = ~src[k]; } EXPORT_SYMBOL(__bitmap_complement); /** * __bitmap_shift_right - logical right shift of the bits in a bitmap * @dst : destination bitmap * @src : source bitmap * @shift : shift by this many bits * @nbits : bitmap size, in bits * * Shifting right (dividing) means moving bits in the MS -> LS bit * direction. Zeros are fed into the vacated MS positions and the * LS bits shifted off the bottom are lost. */ void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, unsigned shift, unsigned nbits) { unsigned k, lim = BITS_TO_LONGS(nbits); unsigned off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; unsigned long mask = BITMAP_LAST_WORD_MASK(nbits); for (k = 0; off + k < lim; ++k) { unsigned long upper, lower; /* * If shift is not word aligned, take lower rem bits of * word above and make them the top rem bits of result. */ if (!rem || off + k + 1 >= lim) upper = 0; else { upper = src[off + k + 1]; if (off + k + 1 == lim - 1) upper &= mask; upper <<= (BITS_PER_LONG - rem); } lower = src[off + k]; if (off + k == lim - 1) lower &= mask; lower >>= rem; dst[k] = lower | upper; } if (off) memset(&dst[lim - off], 0, off*sizeof(unsigned long)); } EXPORT_SYMBOL(__bitmap_shift_right); /** * __bitmap_shift_left - logical left shift of the bits in a bitmap * @dst : destination bitmap * @src : source bitmap * @shift : shift by this many bits * @nbits : bitmap size, in bits * * Shifting left (multiplying) means moving bits in the LS -> MS * direction. Zeros are fed into the vacated LS bit positions * and those MS bits shifted off the top are lost. */ void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, unsigned int shift, unsigned int nbits) { int k; unsigned int lim = BITS_TO_LONGS(nbits); unsigned int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG; for (k = lim - off - 1; k >= 0; --k) { unsigned long upper, lower; /* * If shift is not word aligned, take upper rem bits of * word below and make them the bottom rem bits of result. */ if (rem && k > 0) lower = src[k - 1] >> (BITS_PER_LONG - rem); else lower = 0; upper = src[k] << rem; dst[k + off] = lower | upper; } if (off) memset(dst, 0, off*sizeof(unsigned long)); } EXPORT_SYMBOL(__bitmap_shift_left); /** * bitmap_cut() - remove bit region from bitmap and right shift remaining bits * @dst: destination bitmap, might overlap with src * @src: source bitmap * @first: start bit of region to be removed * @cut: number of bits to remove * @nbits: bitmap size, in bits * * Set the n-th bit of @dst iff the n-th bit of @src is set and * n is less than @first, or the m-th bit of @src is set for any * m such that @first <= n < nbits, and m = n + @cut. * * In pictures, example for a big-endian 32-bit architecture: * * The @src bitmap is:: * * 31 63 * | | * 10000000 11000001 11110010 00010101 10000000 11000001 01110010 00010101 * | | | | * 16 14 0 32 * * if @cut is 3, and @first is 14, bits 14-16 in @src are cut and @dst is:: * * 31 63 * | | * 10110000 00011000 00110010 00010101 00010000 00011000 00101110 01000010 * | | | * 14 (bit 17 0 32 * from @src) * * Note that @dst and @src might overlap partially or entirely. * * This is implemented in the obvious way, with a shift and carry * step for each moved bit. Optimisation is left as an exercise * for the compiler. */ void bitmap_cut(unsigned long *dst, const unsigned long *src, unsigned int first, unsigned int cut, unsigned int nbits) { unsigned int len = BITS_TO_LONGS(nbits); unsigned long keep = 0, carry; int i; if (first % BITS_PER_LONG) { keep = src[first / BITS_PER_LONG] & (~0UL >> (BITS_PER_LONG - first % BITS_PER_LONG)); } memmove(dst, src, len * sizeof(*dst)); while (cut--) { for (i = first / BITS_PER_LONG; i < len; i++) { if (i < len - 1) carry = dst[i + 1] & 1UL; else carry = 0; dst[i] = (dst[i] >> 1) | (carry << (BITS_PER_LONG - 1)); } } dst[first / BITS_PER_LONG] &= ~0UL << (first % BITS_PER_LONG); dst[first / BITS_PER_LONG] |= keep; } EXPORT_SYMBOL(bitmap_cut); bool __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k; unsigned int lim = bits/BITS_PER_LONG; unsigned long result = 0; for (k = 0; k < lim; k++) result |= (dst[k] = bitmap1[k] & bitmap2[k]); if (bits % BITS_PER_LONG) result |= (dst[k] = bitmap1[k] & bitmap2[k] & BITMAP_LAST_WORD_MASK(bits)); return result != 0; } EXPORT_SYMBOL(__bitmap_and); void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k; unsigned int nr = BITS_TO_LONGS(bits); for (k = 0; k < nr; k++) dst[k] = bitmap1[k] | bitmap2[k]; } EXPORT_SYMBOL(__bitmap_or); void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k; unsigned int nr = BITS_TO_LONGS(bits); for (k = 0; k < nr; k++) dst[k] = bitmap1[k] ^ bitmap2[k]; } EXPORT_SYMBOL(__bitmap_xor); bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k; unsigned int lim = bits/BITS_PER_LONG; unsigned long result = 0; for (k = 0; k < lim; k++) result |= (dst[k] = bitmap1[k] & ~bitmap2[k]); if (bits % BITS_PER_LONG) result |= (dst[k] = bitmap1[k] & ~bitmap2[k] & BITMAP_LAST_WORD_MASK(bits)); return result != 0; } EXPORT_SYMBOL(__bitmap_andnot); void __bitmap_replace(unsigned long *dst, const unsigned long *old, const unsigned long *new, const unsigned long *mask, unsigned int nbits) { unsigned int k; unsigned int nr = BITS_TO_LONGS(nbits); for (k = 0; k < nr; k++) dst[k] = (old[k] & ~mask[k]) | (new[k] & mask[k]); } EXPORT_SYMBOL(__bitmap_replace); bool __bitmap_intersects(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k, lim = bits/BITS_PER_LONG; for (k = 0; k < lim; ++k) if (bitmap1[k] & bitmap2[k]) return true; if (bits % BITS_PER_LONG) if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) return true; return false; } EXPORT_SYMBOL(__bitmap_intersects); bool __bitmap_subset(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { unsigned int k, lim = bits/BITS_PER_LONG; for (k = 0; k < lim; ++k) if (bitmap1[k] & ~bitmap2[k]) return false; if (bits % BITS_PER_LONG) if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits)) return false; return true; } EXPORT_SYMBOL(__bitmap_subset); #define BITMAP_WEIGHT(FETCH, bits) \ ({ \ unsigned int __bits = (bits), idx, w = 0; \ \ for (idx = 0; idx < __bits / BITS_PER_LONG; idx++) \ w += hweight_long(FETCH); \ \ if (__bits % BITS_PER_LONG) \ w += hweight_long((FETCH) & BITMAP_LAST_WORD_MASK(__bits)); \ \ w; \ }) unsigned int __bitmap_weight(const unsigned long *bitmap, unsigned int bits) { return BITMAP_WEIGHT(bitmap[idx], bits); } EXPORT_SYMBOL(__bitmap_weight); unsigned int __bitmap_weight_and(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { return BITMAP_WEIGHT(bitmap1[idx] & bitmap2[idx], bits); } EXPORT_SYMBOL(__bitmap_weight_and); unsigned int __bitmap_weight_andnot(const unsigned long *bitmap1, const unsigned long *bitmap2, unsigned int bits) { return BITMAP_WEIGHT(bitmap1[idx] & ~bitmap2[idx], bits); } EXPORT_SYMBOL(__bitmap_weight_andnot); void __bitmap_set(unsigned long *map, unsigned int start, int len) { unsigned long *p = map + BIT_WORD(start); const unsigned int size = start + len; int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG); unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start); while (len - bits_to_set >= 0) { *p |= mask_to_set; len -= bits_to_set; bits_to_set = BITS_PER_LONG; mask_to_set = ~0UL; p++; } if (len) { mask_to_set &= BITMAP_LAST_WORD_MASK(size); *p |= mask_to_set; } } EXPORT_SYMBOL(__bitmap_set); void __bitmap_clear(unsigned long *map, unsigned int start, int len) { unsigned long *p = map + BIT_WORD(start); const unsigned int size = start + len; int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG); unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start); while (len - bits_to_clear >= 0) { *p &= ~mask_to_clear; len -= bits_to_clear; bits_to_clear = BITS_PER_LONG; mask_to_clear = ~0UL; p++; } if (len) { mask_to_clear &= BITMAP_LAST_WORD_MASK(size); *p &= ~mask_to_clear; } } EXPORT_SYMBOL(__bitmap_clear); /** * bitmap_find_next_zero_area_off - find a contiguous aligned zero area * @map: The address to base the search on * @size: The bitmap size in bits * @start: The bitnumber to start searching at * @nr: The number of zeroed bits we're looking for * @align_mask: Alignment mask for zero area * @align_offset: Alignment offset for zero area. * * The @align_mask should be one less than a power of 2; the effect is that * the bit offset of all zero areas this function finds plus @align_offset * is multiple of that power of 2. */ unsigned long bitmap_find_next_zero_area_off(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, unsigned long align_mask, unsigned long align_offset) { unsigned long index, end, i; again: index = find_next_zero_bit(map, size, start); /* Align allocation */ index = __ALIGN_MASK(index + align_offset, align_mask) - align_offset; end = index + nr; if (end > size) return end; i = find_next_bit(map, end, index); if (i < end) { start = i + 1; goto again; } return index; } EXPORT_SYMBOL(bitmap_find_next_zero_area_off); /** * bitmap_pos_to_ord - find ordinal of set bit at given position in bitmap * @buf: pointer to a bitmap * @pos: a bit position in @buf (0 <= @pos < @nbits) * @nbits: number of valid bit positions in @buf * * Map the bit at position @pos in @buf (of length @nbits) to the * ordinal of which set bit it is. If it is not set or if @pos * is not a valid bit position, map to -1. * * If for example, just bits 4 through 7 are set in @buf, then @pos * values 4 through 7 will get mapped to 0 through 3, respectively, * and other @pos values will get mapped to -1. When @pos value 7 * gets mapped to (returns) @ord value 3 in this example, that means * that bit 7 is the 3rd (starting with 0th) set bit in @buf. * * The bit positions 0 through @bits are valid positions in @buf. */ static int bitmap_pos_to_ord(const unsigned long *buf, unsigned int pos, unsigned int nbits) { if (pos >= nbits || !test_bit(pos, buf)) return -1; return bitmap_weight(buf, pos); } /** * bitmap_remap - Apply map defined by a pair of bitmaps to another bitmap * @dst: remapped result * @src: subset to be remapped * @old: defines domain of map * @new: defines range of map * @nbits: number of bits in each of these bitmaps * * Let @old and @new define a mapping of bit positions, such that * whatever position is held by the n-th set bit in @old is mapped * to the n-th set bit in @new. In the more general case, allowing * for the possibility that the weight 'w' of @new is less than the * weight of @old, map the position of the n-th set bit in @old to * the position of the m-th set bit in @new, where m == n % w. * * If either of the @old and @new bitmaps are empty, or if @src and * @dst point to the same location, then this routine copies @src * to @dst. * * The positions of unset bits in @old are mapped to themselves * (the identity map). * * Apply the above specified mapping to @src, placing the result in * @dst, clearing any bits previously set in @dst. * * For example, lets say that @old has bits 4 through 7 set, and * @new has bits 12 through 15 set. This defines the mapping of bit * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other * bit positions unchanged. So if say @src comes into this routine * with bits 1, 5 and 7 set, then @dst should leave with bits 1, * 13 and 15 set. */ void bitmap_remap(unsigned long *dst, const unsigned long *src, const unsigned long *old, const unsigned long *new, unsigned int nbits) { unsigned int oldbit, w; if (dst == src) /* following doesn't handle inplace remaps */ return; bitmap_zero(dst, nbits); w = bitmap_weight(new, nbits); for_each_set_bit(oldbit, src, nbits) { int n = bitmap_pos_to_ord(old, oldbit, nbits); if (n < 0 || w == 0) set_bit(oldbit, dst); /* identity map */ else set_bit(find_nth_bit(new, nbits, n % w), dst); } } EXPORT_SYMBOL(bitmap_remap); /** * bitmap_bitremap - Apply map defined by a pair of bitmaps to a single bit * @oldbit: bit position to be mapped * @old: defines domain of map * @new: defines range of map * @bits: number of bits in each of these bitmaps * * Let @old and @new define a mapping of bit positions, such that * whatever position is held by the n-th set bit in @old is mapped * to the n-th set bit in @new. In the more general case, allowing * for the possibility that the weight 'w' of @new is less than the * weight of @old, map the position of the n-th set bit in @old to * the position of the m-th set bit in @new, where m == n % w. * * The positions of unset bits in @old are mapped to themselves * (the identity map). * * Apply the above specified mapping to bit position @oldbit, returning * the new bit position. * * For example, lets say that @old has bits 4 through 7 set, and * @new has bits 12 through 15 set. This defines the mapping of bit * position 4 to 12, 5 to 13, 6 to 14 and 7 to 15, and of all other * bit positions unchanged. So if say @oldbit is 5, then this routine * returns 13. */ int bitmap_bitremap(int oldbit, const unsigned long *old, const unsigned long *new, int bits) { int w = bitmap_weight(new, bits); int n = bitmap_pos_to_ord(old, oldbit, bits); if (n < 0 || w == 0) return oldbit; else return find_nth_bit(new, bits, n % w); } EXPORT_SYMBOL(bitmap_bitremap); #ifdef CONFIG_NUMA /** * bitmap_onto - translate one bitmap relative to another * @dst: resulting translated bitmap * @orig: original untranslated bitmap * @relmap: bitmap relative to which translated * @bits: number of bits in each of these bitmaps * * Set the n-th bit of @dst iff there exists some m such that the * n-th bit of @relmap is set, the m-th bit of @orig is set, and * the n-th bit of @relmap is also the m-th _set_ bit of @relmap. * (If you understood the previous sentence the first time your * read it, you're overqualified for your current job.) * * In other words, @orig is mapped onto (surjectively) @dst, * using the map { <n, m> | the n-th bit of @relmap is the * m-th set bit of @relmap }. * * Any set bits in @orig above bit number W, where W is the * weight of (number of set bits in) @relmap are mapped nowhere. * In particular, if for all bits m set in @orig, m >= W, then * @dst will end up empty. In situations where the possibility * of such an empty result is not desired, one way to avoid it is * to use the bitmap_fold() operator, below, to first fold the * @orig bitmap over itself so that all its set bits x are in the * range 0 <= x < W. The bitmap_fold() operator does this by * setting the bit (m % W) in @dst, for each bit (m) set in @orig. * * Example [1] for bitmap_onto(): * Let's say @relmap has bits 30-39 set, and @orig has bits * 1, 3, 5, 7, 9 and 11 set. Then on return from this routine, * @dst will have bits 31, 33, 35, 37 and 39 set. * * When bit 0 is set in @orig, it means turn on the bit in * @dst corresponding to whatever is the first bit (if any) * that is turned on in @relmap. Since bit 0 was off in the * above example, we leave off that bit (bit 30) in @dst. * * When bit 1 is set in @orig (as in the above example), it * means turn on the bit in @dst corresponding to whatever * is the second bit that is turned on in @relmap. The second * bit in @relmap that was turned on in the above example was * bit 31, so we turned on bit 31 in @dst. * * Similarly, we turned on bits 33, 35, 37 and 39 in @dst, * because they were the 4th, 6th, 8th and 10th set bits * set in @relmap, and the 4th, 6th, 8th and 10th bits of * @orig (i.e. bits 3, 5, 7 and 9) were also set. * * When bit 11 is set in @orig, it means turn on the bit in * @dst corresponding to whatever is the twelfth bit that is * turned on in @relmap. In the above example, there were * only ten bits turned on in @relmap (30..39), so that bit * 11 was set in @orig had no affect on @dst. * * Example [2] for bitmap_fold() + bitmap_onto(): * Let's say @relmap has these ten bits set:: * * 40 41 42 43 45 48 53 61 74 95 * * (for the curious, that's 40 plus the first ten terms of the * Fibonacci sequence.) * * Further lets say we use the following code, invoking * bitmap_fold() then bitmap_onto, as suggested above to * avoid the possibility of an empty @dst result:: * * unsigned long *tmp; // a temporary bitmap's bits * * bitmap_fold(tmp, orig, bitmap_weight(relmap, bits), bits); * bitmap_onto(dst, tmp, relmap, bits); * * Then this table shows what various values of @dst would be, for * various @orig's. I list the zero-based positions of each set bit. * The tmp column shows the intermediate result, as computed by * using bitmap_fold() to fold the @orig bitmap modulo ten * (the weight of @relmap): * * =============== ============== ================= * @orig tmp @dst * 0 0 40 * 1 1 41 * 9 9 95 * 10 0 40 [#f1]_ * 1 3 5 7 1 3 5 7 41 43 48 61 * 0 1 2 3 4 0 1 2 3 4 40 41 42 43 45 * 0 9 18 27 0 9 8 7 40 61 74 95 * 0 10 20 30 0 40 * 0 11 22 33 0 1 2 3 40 41 42 43 * 0 12 24 36 0 2 4 6 40 42 45 53 * 78 102 211 1 2 8 41 42 74 [#f1]_ * =============== ============== ================= * * .. [#f1] * * For these marked lines, if we hadn't first done bitmap_fold() * into tmp, then the @dst result would have been empty. * * If either of @orig or @relmap is empty (no set bits), then @dst * will be returned empty. * * If (as explained above) the only set bits in @orig are in positions * m where m >= W, (where W is the weight of @relmap) then @dst will * once again be returned empty. * * All bits in @dst not set by the above rule are cleared. */ void bitmap_onto(unsigned long *dst, const unsigned long *orig, const unsigned long *relmap, unsigned int bits) { unsigned int n, m; /* same meaning as in above comment */ if (dst == orig) /* following doesn't handle inplace mappings */ return; bitmap_zero(dst, bits); /* * The following code is a more efficient, but less * obvious, equivalent to the loop: * for (m = 0; m < bitmap_weight(relmap, bits); m++) { * n = find_nth_bit(orig, bits, m); * if (test_bit(m, orig)) * set_bit(n, dst); * } */ m = 0; for_each_set_bit(n, relmap, bits) { /* m == bitmap_pos_to_ord(relmap, n, bits) */ if (test_bit(m, orig)) set_bit(n, dst); m++; } } /** * bitmap_fold - fold larger bitmap into smaller, modulo specified size * @dst: resulting smaller bitmap * @orig: original larger bitmap * @sz: specified size * @nbits: number of bits in each of these bitmaps * * For each bit oldbit in @orig, set bit oldbit mod @sz in @dst. * Clear all other bits in @dst. See further the comment and * Example [2] for bitmap_onto() for why and how to use this. */ void bitmap_fold(unsigned long *dst, const unsigned long *orig, unsigned int sz, unsigned int nbits) { unsigned int oldbit; if (dst == orig) /* following doesn't handle inplace mappings */ return; bitmap_zero(dst, nbits); for_each_set_bit(oldbit, orig, nbits) set_bit(oldbit % sz, dst); } #endif /* CONFIG_NUMA */ unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) { return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long), flags); } EXPORT_SYMBOL(bitmap_alloc); unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags) { return bitmap_alloc(nbits, flags | __GFP_ZERO); } EXPORT_SYMBOL(bitmap_zalloc); unsigned long *bitmap_alloc_node(unsigned int nbits, gfp_t flags, int node) { return kmalloc_array_node(BITS_TO_LONGS(nbits), sizeof(unsigned long), flags, node); } EXPORT_SYMBOL(bitmap_alloc_node); unsigned long *bitmap_zalloc_node(unsigned int nbits, gfp_t flags, int node) { return bitmap_alloc_node(nbits, flags | __GFP_ZERO, node); } EXPORT_SYMBOL(bitmap_zalloc_node); void bitmap_free(const unsigned long *bitmap) { kfree(bitmap); } EXPORT_SYMBOL(bitmap_free); static void devm_bitmap_free(void *data) { unsigned long *bitmap = data; bitmap_free(bitmap); } unsigned long *devm_bitmap_alloc(struct device *dev, unsigned int nbits, gfp_t flags) { unsigned long *bitmap; int ret; bitmap = bitmap_alloc(nbits, flags); if (!bitmap) return NULL; ret = devm_add_action_or_reset(dev, devm_bitmap_free, bitmap); if (ret) return NULL; return bitmap; } EXPORT_SYMBOL_GPL(devm_bitmap_alloc); unsigned long *devm_bitmap_zalloc(struct device *dev, unsigned int nbits, gfp_t flags) { return devm_bitmap_alloc(dev, nbits, flags | __GFP_ZERO); } EXPORT_SYMBOL_GPL(devm_bitmap_zalloc); #if BITS_PER_LONG == 64 /** * bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap * @bitmap: array of unsigned longs, the destination bitmap * @buf: array of u32 (in host byte order), the source bitmap * @nbits: number of bits in @bitmap */ void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, unsigned int nbits) { unsigned int i, halfwords; halfwords = DIV_ROUND_UP(nbits, 32); for (i = 0; i < halfwords; i++) { bitmap[i/2] = (unsigned long) buf[i]; if (++i < halfwords) bitmap[i/2] |= ((unsigned long) buf[i]) << 32; } /* Clear tail bits in last word beyond nbits. */ if (nbits % BITS_PER_LONG) bitmap[(halfwords - 1) / 2] &= BITMAP_LAST_WORD_MASK(nbits); } EXPORT_SYMBOL(bitmap_from_arr32); /** * bitmap_to_arr32 - copy the contents of bitmap to a u32 array of bits * @buf: array of u32 (in host byte order), the dest bitmap * @bitmap: array of unsigned longs, the source bitmap * @nbits: number of bits in @bitmap */ void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits) { unsigned int i, halfwords; halfwords = DIV_ROUND_UP(nbits, 32); for (i = 0; i < halfwords; i++) { buf[i] = (u32) (bitmap[i/2] & UINT_MAX); if (++i < halfwords) buf[i] = (u32) (bitmap[i/2] >> 32); } /* Clear tail bits in last element of array beyond nbits. */ if (nbits % BITS_PER_LONG) buf[halfwords - 1] &= (u32) (UINT_MAX >> ((-nbits) & 31)); } EXPORT_SYMBOL(bitmap_to_arr32); #endif #if BITS_PER_LONG == 32 /** * bitmap_from_arr64 - copy the contents of u64 array of bits to bitmap * @bitmap: array of unsigned longs, the destination bitmap * @buf: array of u64 (in host byte order), the source bitmap * @nbits: number of bits in @bitmap */ void bitmap_from_arr64(unsigned long *bitmap, const u64 *buf, unsigned int nbits) { int n; for (n = nbits; n > 0; n -= 64) { u64 val = *buf++; *bitmap++ = val; if (n > 32) *bitmap++ = val >> 32; } /* * Clear tail bits in the last word beyond nbits. * * Negative index is OK because here we point to the word next * to the last word of the bitmap, except for nbits == 0, which * is tested implicitly. */ if (nbits % BITS_PER_LONG) bitmap[-1] &= BITMAP_LAST_WORD_MASK(nbits); } EXPORT_SYMBOL(bitmap_from_arr64); /** * bitmap_to_arr64 - copy the contents of bitmap to a u64 array of bits * @buf: array of u64 (in host byte order), the dest bitmap * @bitmap: array of unsigned longs, the source bitmap * @nbits: number of bits in @bitmap */ void bitmap_to_arr64(u64 *buf, const unsigned long *bitmap, unsigned int nbits) { const unsigned long *end = bitmap + BITS_TO_LONGS(nbits); while (bitmap < end) { *buf = *bitmap++; if (bitmap < end) *buf |= (u64)(*bitmap++) << 32; buf++; } /* Clear tail bits in the last element of array beyond nbits. */ if (nbits % 64) buf[-1] &= GENMASK_ULL((nbits - 1) % 64, 0); } EXPORT_SYMBOL(bitmap_to_arr64); #endif
316 6 6 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 // SPDX-License-Identifier: GPL-2.0 #include <linux/kernel.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/of_address.h> #include <linux/of_iommu.h> #include <linux/of_reserved_mem.h> #include <linux/dma-direct.h> /* for bus_dma_region */ #include <linux/dma-map-ops.h> #include <linux/init.h> #include <linux/mod_devicetable.h> #include <linux/slab.h> #include <linux/platform_device.h> #include <asm/errno.h> #include "of_private.h" /** * of_match_device - Tell if a struct device matches an of_device_id list * @matches: array of of device match structures to search in * @dev: the of device structure to match against * * Used by a driver to check whether an platform_device present in the * system is in its list of supported devices. */ const struct of_device_id *of_match_device(const struct of_device_id *matches, const struct device *dev) { if (!matches || !dev->of_node || dev->of_node_reused) return NULL; return of_match_node(matches, dev->of_node); } EXPORT_SYMBOL(of_match_device); static void of_dma_set_restricted_buffer(struct device *dev, struct device_node *np) { struct device_node *node, *of_node = dev->of_node; int count, i; if (!IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL)) return; count = of_property_count_elems_of_size(of_node, "memory-region", sizeof(u32)); /* * If dev->of_node doesn't exist or doesn't contain memory-region, try * the OF node having DMA configuration. */ if (count <= 0) { of_node = np; count = of_property_count_elems_of_size( of_node, "memory-region", sizeof(u32)); } for (i = 0; i < count; i++) { node = of_parse_phandle(of_node, "memory-region", i); /* * There might be multiple memory regions, but only one * restricted-dma-pool region is allowed. */ if (of_device_is_compatible(node, "restricted-dma-pool") && of_device_is_available(node)) { of_node_put(node); break; } of_node_put(node); } /* * Attempt to initialize a restricted-dma-pool region if one was found. * Note that count can hold a negative error code. */ if (i < count && of_reserved_mem_device_init_by_idx(dev, of_node, i)) dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n"); } /** * of_dma_configure_id - Setup DMA configuration * @dev: Device to apply DMA configuration * @np: Pointer to OF node having DMA configuration * @force_dma: Whether device is to be set up by of_dma_configure() even if * DMA capability is not explicitly described by firmware. * @id: Optional const pointer value input id * * Try to get devices's DMA configuration from DT and update it * accordingly. * * If platform code needs to use its own special DMA configuration, it * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events * to fix up DMA configuration. */ int of_dma_configure_id(struct device *dev, struct device_node *np, bool force_dma, const u32 *id) { const struct bus_dma_region *map = NULL; struct device_node *bus_np; u64 mask, end = 0; bool coherent; int iommu_ret; int ret; if (np == dev->of_node) bus_np = __of_get_dma_parent(np); else bus_np = of_node_get(np); ret = of_dma_get_range(bus_np, &map); of_node_put(bus_np); if (ret < 0) { /* * For legacy reasons, we have to assume some devices need * DMA configuration regardless of whether "dma-ranges" is * correctly specified or not. */ if (!force_dma) return ret == -ENODEV ? 0 : ret; } else { /* Determine the overall bounds of all DMA regions */ end = dma_range_map_max(map); } /* * If @dev is expected to be DMA-capable then the bus code that created * it should have initialised its dma_mask pointer by this point. For * now, we'll continue the legacy behaviour of coercing it to the * coherent mask if not, but we'll no longer do so quietly. */ if (!dev->dma_mask) { dev_warn(dev, "DMA mask not set\n"); dev->dma_mask = &dev->coherent_dma_mask; } if (!end && dev->coherent_dma_mask) end = dev->coherent_dma_mask; else if (!end) end = (1ULL << 32) - 1; /* * Limit coherent and dma mask based on size and default mask * set by the driver. */ mask = DMA_BIT_MASK(ilog2(end) + 1); dev->coherent_dma_mask &= mask; *dev->dma_mask &= mask; /* ...but only set bus limit and range map if we found valid dma-ranges earlier */ if (!ret) { dev->bus_dma_limit = end; dev->dma_range_map = map; } coherent = of_dma_is_coherent(np); dev_dbg(dev, "device is%sdma coherent\n", coherent ? " " : " not "); iommu_ret = of_iommu_configure(dev, np, id); if (iommu_ret == -EPROBE_DEFER) { /* Don't touch range map if it wasn't set from a valid dma-ranges */ if (!ret) dev->dma_range_map = NULL; kfree(map); return -EPROBE_DEFER; } else if (iommu_ret == -ENODEV) { dev_dbg(dev, "device is not behind an iommu\n"); } else if (iommu_ret) { dev_err(dev, "iommu configuration for device failed with %pe\n", ERR_PTR(iommu_ret)); /* * Historically this routine doesn't fail driver probing * due to errors in of_iommu_configure() */ } else dev_dbg(dev, "device is behind an iommu\n"); arch_setup_dma_ops(dev, coherent); if (iommu_ret) of_dma_set_restricted_buffer(dev, np); return 0; } EXPORT_SYMBOL_GPL(of_dma_configure_id); const void *of_device_get_match_data(const struct device *dev) { const struct of_device_id *match; match = of_match_device(dev->driver->of_match_table, dev); if (!match) return NULL; return match->data; } EXPORT_SYMBOL(of_device_get_match_data); /** * of_device_modalias - Fill buffer with newline terminated modalias string * @dev: Calling device * @str: Modalias string * @len: Size of @str */ ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len) { ssize_t sl; if (!dev || !dev->of_node || dev->of_node_reused) return -ENODEV; sl = of_modalias(dev->of_node, str, len - 2); if (sl < 0) return sl; if (sl > len - 2) return -ENOMEM; str[sl++] = '\n'; str[sl] = 0; return sl; } EXPORT_SYMBOL_GPL(of_device_modalias); /** * of_device_uevent - Display OF related uevent information * @dev: Device to display the uevent information for * @env: Kernel object's userspace event reference to fill up */ void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env) { const char *compat, *type; struct alias_prop *app; struct property *p; int seen = 0; if ((!dev) || (!dev->of_node)) return; add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node); add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node); type = of_node_get_device_type(dev->of_node); if (type) add_uevent_var(env, "OF_TYPE=%s", type); /* Since the compatible field can contain pretty much anything * it's not really legal to split it out with commas. We split it * up using a number of environment variables instead. */ of_property_for_each_string(dev->of_node, "compatible", p, compat) { add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat); seen++; } add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen); seen = 0; mutex_lock(&of_mutex); list_for_each_entry(app, &aliases_lookup, link) { if (dev->of_node == app->np) { add_uevent_var(env, "OF_ALIAS_%d=%s", seen, app->alias); seen++; } } mutex_unlock(&of_mutex); } EXPORT_SYMBOL_GPL(of_device_uevent); int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env) { int sl; if ((!dev) || (!dev->of_node) || dev->of_node_reused) return -ENODEV; /* Devicetree modalias is tricky, we add it in 2 steps */ if (add_uevent_var(env, "MODALIAS=")) return -ENOMEM; sl = of_modalias(dev->of_node, &env->buf[env->buflen-1], sizeof(env->buf) - env->buflen); if (sl < 0) return sl; if (sl >= (sizeof(env->buf) - env->buflen)) return -ENOMEM; env->buflen += sl; return 0; } EXPORT_SYMBOL_GPL(of_device_uevent_modalias); /** * of_device_make_bus_id - Use the device node data to assign a unique name * @dev: pointer to device structure that is linked to a device tree node * * This routine will first try using the translated bus address to * derive a unique name. If it cannot, then it will prepend names from * parent nodes until a unique name can be derived. */ void of_device_make_bus_id(struct device *dev) { struct device_node *node = dev->of_node; const __be32 *reg; u64 addr; u32 mask; /* Construct the name, using parent nodes if necessary to ensure uniqueness */ while (node->parent) { /* * If the address can be translated, then that is as much * uniqueness as we need. Make it the first component and return */ reg = of_get_property(node, "reg", NULL); if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) { if (!of_property_read_u32(node, "mask", &mask)) dev_set_name(dev, dev_name(dev) ? "%llx.%x.%pOFn:%s" : "%llx.%x.%pOFn", addr, ffs(mask) - 1, node, dev_name(dev)); else dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn", addr, node, dev_name(dev)); return; } /* format arguments only used if dev_name() resolves to NULL */ dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s", kbasename(node->full_name), dev_name(dev)); node = node->parent; } } EXPORT_SYMBOL_GPL(of_device_make_bus_id);
653 42 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_X86_JUMP_LABEL_H #define _ASM_X86_JUMP_LABEL_H #define HAVE_JUMP_LABEL_BATCH #include <asm/asm.h> #include <asm/nops.h> #ifndef __ASSEMBLY__ #include <linux/stringify.h> #include <linux/types.h> #define JUMP_TABLE_ENTRY \ ".pushsection __jump_table, \"aw\" \n\t" \ _ASM_ALIGN "\n\t" \ ".long 1b - . \n\t" \ ".long %l[l_yes] - . \n\t" \ _ASM_PTR "%c0 + %c1 - .\n\t" \ ".popsection \n\t" #ifdef CONFIG_HAVE_JUMP_LABEL_HACK static __always_inline bool arch_static_branch(struct static_key *key, bool branch) { asm goto("1:" "jmp %l[l_yes] # objtool NOPs this \n\t" JUMP_TABLE_ENTRY : : "i" (key), "i" (2 | branch) : : l_yes); return false; l_yes: return true; } #else /* !CONFIG_HAVE_JUMP_LABEL_HACK */ static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch) { asm goto("1:" ".byte " __stringify(BYTES_NOP5) "\n\t" JUMP_TABLE_ENTRY : : "i" (key), "i" (branch) : : l_yes); return false; l_yes: return true; } #endif /* CONFIG_HAVE_JUMP_LABEL_HACK */ static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch) { asm goto("1:" "jmp %l[l_yes]\n\t" JUMP_TABLE_ENTRY : : "i" (key), "i" (branch) : : l_yes); return false; l_yes: return true; } extern int arch_jump_entry_size(struct jump_entry *entry); #endif /* __ASSEMBLY__ */ #endif
331 365 362 360 4 4 358 366 366 366 360 362 362 360 362 361 361 3 3 3 5 5 5 5 5 5 330 330 6 330 5 330 165 7 166 159 163 166 165 8 1 8 156 156 7 163 166 162 162 158 2 156 5 152 167 167 165 166 166 158 156 162 164 309 161 160 153 150 156 187 330 328 329 13 13 13 13 13 13 13 3 1 2 3 307 306 249 306 332 332 331 331 208 332 332 208 332 332 332 284 232 233 232 208 208 208 315 314 307 308 308 307 308 306 201 200 206 207 208 330 332 331 332 332 332 332 188 151 15 15 15 15 199 201 200 232 232 233 4 4 4 4 4 4 4 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 // SPDX-License-Identifier: GPL-2.0 /* * message.c - synchronous message handling * * Released under the GPLv2 only. */ #include <linux/acpi.h> #include <linux/pci.h> /* for scatterlist macros */ #include <linux/usb.h> #include <linux/module.h> #include <linux/of.h> #include <linux/slab.h> #include <linux/mm.h> #include <linux/timer.h> #include <linux/ctype.h> #include <linux/nls.h> #include <linux/device.h> #include <linux/scatterlist.h> #include <linux/usb/cdc.h> #include <linux/usb/quirks.h> #include <linux/usb/hcd.h> /* for usbcore internals */ #include <linux/usb/of.h> #include <asm/byteorder.h> #include "usb.h" static void cancel_async_set_config(struct usb_device *udev); struct api_context { struct completion done; int status; }; static void usb_api_blocking_completion(struct urb *urb) { struct api_context *ctx = urb->context; ctx->status = urb->status; complete(&ctx->done); } /* * Starts urb and waits for completion or timeout. Note that this call * is NOT interruptible. Many device driver i/o requests should be * interruptible and therefore these drivers should implement their * own interruptible routines. */ static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length) { struct api_context ctx; unsigned long expire; int retval; init_completion(&ctx.done); urb->context = &ctx; urb->actual_length = 0; retval = usb_submit_urb(urb, GFP_NOIO); if (unlikely(retval)) goto out; expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT; if (!wait_for_completion_timeout(&ctx.done, expire)) { usb_kill_urb(urb); retval = (ctx.status == -ENOENT ? -ETIMEDOUT : ctx.status); dev_dbg(&urb->dev->dev, "%s timed out on ep%d%s len=%u/%u\n", current->comm, usb_endpoint_num(&urb->ep->desc), usb_urb_dir_in(urb) ? "in" : "out", urb->actual_length, urb->transfer_buffer_length); } else retval = ctx.status; out: if (actual_length) *actual_length = urb->actual_length; usb_free_urb(urb); return retval; } /*-------------------------------------------------------------------*/ /* returns status (negative) or length (positive) */ static int usb_internal_control_msg(struct usb_device *usb_dev, unsigned int pipe, struct usb_ctrlrequest *cmd, void *data, int len, int timeout) { struct urb *urb; int retv; int length; urb = usb_alloc_urb(0, GFP_NOIO); if (!urb) return -ENOMEM; usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char *)cmd, data, len, usb_api_blocking_completion, NULL); retv = usb_start_wait_urb(urb, timeout, &length); if (retv < 0) return retv; else return length; } /** * usb_control_msg - Builds a control urb, sends it off and waits for completion * @dev: pointer to the usb device to send the message to * @pipe: endpoint "pipe" to send the message to * @request: USB message request value * @requesttype: USB message request type value * @value: USB message value * @index: USB message index value * @data: pointer to the data to send * @size: length in bytes of the data to send * @timeout: time in msecs to wait for the message to complete before timing * out (if 0 the wait is forever) * * Context: task context, might sleep. * * This function sends a simple control message to a specified endpoint and * waits for the message to complete, or timeout. * * Don't use this function from within an interrupt context. If you need * an asynchronous message, or need to send a message from within interrupt * context, use usb_submit_urb(). If a thread in your driver uses this call, * make sure your disconnect() method can wait for it to complete. Since you * don't have a handle on the URB used, you can't cancel the request. * * Return: If successful, the number of bytes transferred. Otherwise, a negative * error number. */ int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u8 requesttype, __u16 value, __u16 index, void *data, __u16 size, int timeout) { struct usb_ctrlrequest *dr; int ret; dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO); if (!dr) return -ENOMEM; dr->bRequestType = requesttype; dr->bRequest = request; dr->wValue = cpu_to_le16(value); dr->wIndex = cpu_to_le16(index); dr->wLength = cpu_to_le16(size); ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout); /* Linger a bit, prior to the next control message. */ if (dev->quirks & USB_QUIRK_DELAY_CTRL_MSG) msleep(200); kfree(dr); return ret; } EXPORT_SYMBOL_GPL(usb_control_msg); /** * usb_control_msg_send - Builds a control "send" message, sends it off and waits for completion * @dev: pointer to the usb device to send the message to * @endpoint: endpoint to send the message to * @request: USB message request value * @requesttype: USB message request type value * @value: USB message value * @index: USB message index value * @driver_data: pointer to the data to send * @size: length in bytes of the data to send * @timeout: time in msecs to wait for the message to complete before timing * out (if 0 the wait is forever) * @memflags: the flags for memory allocation for buffers * * Context: !in_interrupt () * * This function sends a control message to a specified endpoint that is not * expected to fill in a response (i.e. a "send message") and waits for the * message to complete, or timeout. * * Do not use this function from within an interrupt context. If you need * an asynchronous message, or need to send a message from within interrupt * context, use usb_submit_urb(). If a thread in your driver uses this call, * make sure your disconnect() method can wait for it to complete. Since you * don't have a handle on the URB used, you can't cancel the request. * * The data pointer can be made to a reference on the stack, or anywhere else, * as it will not be modified at all. This does not have the restriction that * usb_control_msg() has where the data pointer must be to dynamically allocated * memory (i.e. memory that can be successfully DMAed to a device). * * Return: If successful, 0 is returned, Otherwise, a negative error number. */ int usb_control_msg_send(struct usb_device *dev, __u8 endpoint, __u8 request, __u8 requesttype, __u16 value, __u16 index, const void *driver_data, __u16 size, int timeout, gfp_t memflags) { unsigned int pipe = usb_sndctrlpipe(dev, endpoint); int ret; u8 *data = NULL; if (size) { data = kmemdup(driver_data, size, memflags); if (!data) return -ENOMEM; } ret = usb_control_msg(dev, pipe, request, requesttype, value, index, data, size, timeout); kfree(data); if (ret < 0) return ret; return 0; } EXPORT_SYMBOL_GPL(usb_control_msg_send); /** * usb_control_msg_recv - Builds a control "receive" message, sends it off and waits for completion * @dev: pointer to the usb device to send the message to * @endpoint: endpoint to send the message to * @request: USB message request value * @requesttype: USB message request type value * @value: USB message value * @index: USB message index value * @driver_data: pointer to the data to be filled in by the message * @size: length in bytes of the data to be received * @timeout: time in msecs to wait for the message to complete before timing * out (if 0 the wait is forever) * @memflags: the flags for memory allocation for buffers * * Context: !in_interrupt () * * This function sends a control message to a specified endpoint that is * expected to fill in a response (i.e. a "receive message") and waits for the * message to complete, or timeout. * * Do not use this function from within an interrupt context. If you need * an asynchronous message, or need to send a message from within interrupt * context, use usb_submit_urb(). If a thread in your driver uses this call, * make sure your disconnect() method can wait for it to complete. Since you * don't have a handle on the URB used, you can't cancel the request. * * The data pointer can be made to a reference on the stack, or anywhere else * that can be successfully written to. This function does not have the * restriction that usb_control_msg() has where the data pointer must be to * dynamically allocated memory (i.e. memory that can be successfully DMAed to a * device). * * The "whole" message must be properly received from the device in order for * this function to be successful. If a device returns less than the expected * amount of data, then the function will fail. Do not use this for messages * where a variable amount of data might be returned. * * Return: If successful, 0 is returned, Otherwise, a negative error number. */ int usb_control_msg_recv(struct usb_device *dev, __u8 endpoint, __u8 request, __u8 requesttype, __u16 value, __u16 index, void *driver_data, __u16 size, int timeout, gfp_t memflags) { unsigned int pipe = usb_rcvctrlpipe(dev, endpoint); int ret; u8 *data; if (!size || !driver_data) return -EINVAL; data = kmalloc(size, memflags); if (!data) return -ENOMEM; ret = usb_control_msg(dev, pipe, request, requesttype, value, index, data, size, timeout); if (ret < 0) goto exit; if (ret == size) { memcpy(driver_data, data, size); ret = 0; } else { ret = -EREMOTEIO; } exit: kfree(data); return ret; } EXPORT_SYMBOL_GPL(usb_control_msg_recv); /** * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion * @usb_dev: pointer to the usb device to send the message to * @pipe: endpoint "pipe" to send the message to * @data: pointer to the data to send * @len: length in bytes of the data to send * @actual_length: pointer to a location to put the actual length transferred * in bytes * @timeout: time in msecs to wait for the message to complete before * timing out (if 0 the wait is forever) * * Context: task context, might sleep. * * This function sends a simple interrupt message to a specified endpoint and * waits for the message to complete, or timeout. * * Don't use this function from within an interrupt context. If you need * an asynchronous message, or need to send a message from within interrupt * context, use usb_submit_urb() If a thread in your driver uses this call, * make sure your disconnect() method can wait for it to complete. Since you * don't have a handle on the URB used, you can't cancel the request. * * Return: * If successful, 0. Otherwise a negative error number. The number of actual * bytes transferred will be stored in the @actual_length parameter. */ int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe, void *data, int len, int *actual_length, int timeout) { return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout); } EXPORT_SYMBOL_GPL(usb_interrupt_msg); /** * usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion * @usb_dev: pointer to the usb device to send the message to * @pipe: endpoint "pipe" to send the message to * @data: pointer to the data to send * @len: length in bytes of the data to send * @actual_length: pointer to a location to put the actual length transferred * in bytes * @timeout: time in msecs to wait for the message to complete before * timing out (if 0 the wait is forever) * * Context: task context, might sleep. * * This function sends a simple bulk message to a specified endpoint * and waits for the message to complete, or timeout. * * Don't use this function from within an interrupt context. If you need * an asynchronous message, or need to send a message from within interrupt * context, use usb_submit_urb() If a thread in your driver uses this call, * make sure your disconnect() method can wait for it to complete. Since you * don't have a handle on the URB used, you can't cancel the request. * * Because there is no usb_interrupt_msg() and no USBDEVFS_INTERRUPT ioctl, * users are forced to abuse this routine by using it to submit URBs for * interrupt endpoints. We will take the liberty of creating an interrupt URB * (with the default interval) if the target is an interrupt endpoint. * * Return: * If successful, 0. Otherwise a negative error number. The number of actual * bytes transferred will be stored in the @actual_length parameter. * */ int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe, void *data, int len, int *actual_length, int timeout) { struct urb *urb; struct usb_host_endpoint *ep; ep = usb_pipe_endpoint(usb_dev, pipe); if (!ep || len < 0) return -EINVAL; urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) return -ENOMEM; if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT) { pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30); usb_fill_int_urb(urb, usb_dev, pipe, data, len, usb_api_blocking_completion, NULL, ep->desc.bInterval); } else usb_fill_bulk_urb(urb, usb_dev, pipe, data, len, usb_api_blocking_completion, NULL); return usb_start_wait_urb(urb, timeout, actual_length); } EXPORT_SYMBOL_GPL(usb_bulk_msg); /*-------------------------------------------------------------------*/ static void sg_clean(struct usb_sg_request *io) { if (io->urbs) { while (io->entries--) usb_free_urb(io->urbs[io->entries]); kfree(io->urbs); io->urbs = NULL; } io->dev = NULL; } static void sg_complete(struct urb *urb) { unsigned long flags; struct usb_sg_request *io = urb->context; int status = urb->status; spin_lock_irqsave(&io->lock, flags); /* In 2.5 we require hcds' endpoint queues not to progress after fault * reports, until the completion callback (this!) returns. That lets * device driver code (like this routine) unlink queued urbs first, * if it needs to, since the HC won't work on them at all. So it's * not possible for page N+1 to overwrite page N, and so on. * * That's only for "hard" faults; "soft" faults (unlinks) sometimes * complete before the HCD can get requests away from hardware, * though never during cleanup after a hard fault. */ if (io->status && (io->status != -ECONNRESET || status != -ECONNRESET) && urb->actual_length) { dev_err(io->dev->bus->controller, "dev %s ep%d%s scatterlist error %d/%d\n", io->dev->devpath, usb_endpoint_num(&urb->ep->desc), usb_urb_dir_in(urb) ? "in" : "out", status, io->status); /* BUG (); */ } if (io->status == 0 && status && status != -ECONNRESET) { int i, found, retval; io->status = status; /* the previous urbs, and this one, completed already. * unlink pending urbs so they won't rx/tx bad data. * careful: unlink can sometimes be synchronous... */ spin_unlock_irqrestore(&io->lock, flags); for (i = 0, found = 0; i < io->entries; i++) { if (!io->urbs[i]) continue; if (found) { usb_block_urb(io->urbs[i]); retval = usb_unlink_urb(io->urbs[i]); if (retval != -EINPROGRESS && retval != -ENODEV && retval != -EBUSY && retval != -EIDRM) dev_err(&io->dev->dev, "%s, unlink --> %d\n", __func__, retval); } else if (urb == io->urbs[i]) found = 1; } spin_lock_irqsave(&io->lock, flags); } /* on the last completion, signal usb_sg_wait() */ io->bytes += urb->actual_length; io->count--; if (!io->count) complete(&io->complete); spin_unlock_irqrestore(&io->lock, flags); } /** * usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request * @io: request block being initialized. until usb_sg_wait() returns, * treat this as a pointer to an opaque block of memory, * @dev: the usb device that will send or receive the data * @pipe: endpoint "pipe" used to transfer the data * @period: polling rate for interrupt endpoints, in frames or * (for high speed endpoints) microframes; ignored for bulk * @sg: scatterlist entries * @nents: how many entries in the scatterlist * @length: how many bytes to send from the scatterlist, or zero to * send every byte identified in the list. * @mem_flags: SLAB_* flags affecting memory allocations in this call * * This initializes a scatter/gather request, allocating resources such as * I/O mappings and urb memory (except maybe memory used by USB controller * drivers). * * The request must be issued using usb_sg_wait(), which waits for the I/O to * complete (or to be canceled) and then cleans up all resources allocated by * usb_sg_init(). * * The request may be canceled with usb_sg_cancel(), either before or after * usb_sg_wait() is called. * * Return: Zero for success, else a negative errno value. */ int usb_sg_init(struct usb_sg_request *io, struct usb_device *dev, unsigned pipe, unsigned period, struct scatterlist *sg, int nents, size_t length, gfp_t mem_flags) { int i; int urb_flags; int use_sg; if (!io || !dev || !sg || usb_pipecontrol(pipe) || usb_pipeisoc(pipe) || nents <= 0) return -EINVAL; spin_lock_init(&io->lock); io->dev = dev; io->pipe = pipe; if (dev->bus->sg_tablesize > 0) { use_sg = true; io->entries = 1; } else { use_sg = false; io->entries = nents; } /* initialize all the urbs we'll use */ io->urbs = kmalloc_array(io->entries, sizeof(*io->urbs), mem_flags); if (!io->urbs) goto nomem; urb_flags = URB_NO_INTERRUPT; if (usb_pipein(pipe)) urb_flags |= URB_SHORT_NOT_OK; for_each_sg(sg, sg, io->entries, i) { struct urb *urb; unsigned len; urb = usb_alloc_urb(0, mem_flags); if (!urb) { io->entries = i; goto nomem; } io->urbs[i] = urb; urb->dev = NULL; urb->pipe = pipe; urb->interval = period; urb->transfer_flags = urb_flags; urb->complete = sg_complete; urb->context = io; urb->sg = sg; if (use_sg) { /* There is no single transfer buffer */ urb->transfer_buffer = NULL; urb->num_sgs = nents; /* A length of zero means transfer the whole sg list */ len = length; if (len == 0) { struct scatterlist *sg2; int j; for_each_sg(sg, sg2, nents, j) len += sg2->length; } } else { /* * Some systems can't use DMA; they use PIO instead. * For their sakes, transfer_buffer is set whenever * possible. */ if (!PageHighMem(sg_page(sg))) urb->transfer_buffer = sg_virt(sg); else urb->transfer_buffer = NULL; len = sg->length; if (length) { len = min_t(size_t, len, length); length -= len; if (length == 0) io->entries = i + 1; } } urb->transfer_buffer_length = len; } io->urbs[--i]->transfer_flags &= ~URB_NO_INTERRUPT; /* transaction state */ io->count = io->entries; io->status = 0; io->bytes = 0; init_completion(&io->complete); return 0; nomem: sg_clean(io); return -ENOMEM; } EXPORT_SYMBOL_GPL(usb_sg_init); /** * usb_sg_wait - synchronously execute scatter/gather request * @io: request block handle, as initialized with usb_sg_init(). * some fields become accessible when this call returns. * * Context: task context, might sleep. * * This function blocks until the specified I/O operation completes. It * leverages the grouping of the related I/O requests to get good transfer * rates, by queueing the requests. At higher speeds, such queuing can * significantly improve USB throughput. * * There are three kinds of completion for this function. * * (1) success, where io->status is zero. The number of io->bytes * transferred is as requested. * (2) error, where io->status is a negative errno value. The number * of io->bytes transferred before the error is usually less * than requested, and can be nonzero. * (3) cancellation, a type of error with status -ECONNRESET that * is initiated by usb_sg_cancel(). * * When this function returns, all memory allocated through usb_sg_init() or * this call will have been freed. The request block parameter may still be * passed to usb_sg_cancel(), or it may be freed. It could also be * reinitialized and then reused. * * Data Transfer Rates: * * Bulk transfers are valid for full or high speed endpoints. * The best full speed data rate is 19 packets of 64 bytes each * per frame, or 1216 bytes per millisecond. * The best high speed data rate is 13 packets of 512 bytes each * per microframe, or 52 KBytes per millisecond. * * The reason to use interrupt transfers through this API would most likely * be to reserve high speed bandwidth, where up to 24 KBytes per millisecond * could be transferred. That capability is less useful for low or full * speed interrupt endpoints, which allow at most one packet per millisecond, * of at most 8 or 64 bytes (respectively). * * It is not necessary to call this function to reserve bandwidth for devices * under an xHCI host controller, as the bandwidth is reserved when the * configuration or interface alt setting is selected. */ void usb_sg_wait(struct usb_sg_request *io) { int i; int entries = io->entries; /* queue the urbs. */ spin_lock_irq(&io->lock); i = 0; while (i < entries && !io->status) { int retval; io->urbs[i]->dev = io->dev; spin_unlock_irq(&io->lock); retval = usb_submit_urb(io->urbs[i], GFP_NOIO); switch (retval) { /* maybe we retrying will recover */ case -ENXIO: /* hc didn't queue this one */ case -EAGAIN: case -ENOMEM: retval = 0; yield(); break; /* no error? continue immediately. * * NOTE: to work better with UHCI (4K I/O buffer may * need 3K of TDs) it may be good to limit how many * URBs are queued at once; N milliseconds? */ case 0: ++i; cpu_relax(); break; /* fail any uncompleted urbs */ default: io->urbs[i]->status = retval; dev_dbg(&io->dev->dev, "%s, submit --> %d\n", __func__, retval); usb_sg_cancel(io); } spin_lock_irq(&io->lock); if (retval && (io->status == 0 || io->status == -ECONNRESET)) io->status = retval; } io->count -= entries - i; if (io->count == 0) complete(&io->complete); spin_unlock_irq(&io->lock); /* OK, yes, this could be packaged as non-blocking. * So could the submit loop above ... but it's easier to * solve neither problem than to solve both! */ wait_for_completion(&io->complete); sg_clean(io); } EXPORT_SYMBOL_GPL(usb_sg_wait); /** * usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait() * @io: request block, initialized with usb_sg_init() * * This stops a request after it has been started by usb_sg_wait(). * It can also prevents one initialized by usb_sg_init() from starting, * so that call just frees resources allocated to the request. */ void usb_sg_cancel(struct usb_sg_request *io) { unsigned long flags; int i, retval; spin_lock_irqsave(&io->lock, flags); if (io->status || io->count == 0) { spin_unlock_irqrestore(&io->lock, flags); return; } /* shut everything down */ io->status = -ECONNRESET; io->count++; /* Keep the request alive until we're done */ spin_unlock_irqrestore(&io->lock, flags); for (i = io->entries - 1; i >= 0; --i) { usb_block_urb(io->urbs[i]); retval = usb_unlink_urb(io->urbs[i]); if (retval != -EINPROGRESS && retval != -ENODEV && retval != -EBUSY && retval != -EIDRM) dev_warn(&io->dev->dev, "%s, unlink --> %d\n", __func__, retval); } spin_lock_irqsave(&io->lock, flags); io->count--; if (!io->count) complete(&io->complete); spin_unlock_irqrestore(&io->lock, flags); } EXPORT_SYMBOL_GPL(usb_sg_cancel); /*-------------------------------------------------------------------*/ /** * usb_get_descriptor - issues a generic GET_DESCRIPTOR request * @dev: the device whose descriptor is being retrieved * @type: the descriptor type (USB_DT_*) * @index: the number of the descriptor * @buf: where to put the descriptor * @size: how big is "buf"? * * Context: task context, might sleep. * * Gets a USB descriptor. Convenience functions exist to simplify * getting some types of descriptors. Use * usb_get_string() or usb_string() for USB_DT_STRING. * Device (USB_DT_DEVICE) and configuration descriptors (USB_DT_CONFIG) * are part of the device structure. * In addition to a number of USB-standard descriptors, some * devices also use class-specific or vendor-specific descriptors. * * This call is synchronous, and may not be used in an interrupt context. * * Return: The number of bytes received on success, or else the status code * returned by the underlying usb_control_msg() call. */ int usb_get_descriptor(struct usb_device *dev, unsigned char type, unsigned char index, void *buf, int size) { int i; int result; if (size <= 0) /* No point in asking for no data */ return -EINVAL; memset(buf, 0, size); /* Make sure we parse really received data */ for (i = 0; i < 3; ++i) { /* retry on length 0 or error; some devices are flakey */ result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, (type << 8) + index, 0, buf, size, USB_CTRL_GET_TIMEOUT); if (result <= 0 && result != -ETIMEDOUT) continue; if (result > 1 && ((u8 *)buf)[1] != type) { result = -ENODATA; continue; } break; } return result; } EXPORT_SYMBOL_GPL(usb_get_descriptor); /** * usb_get_string - gets a string descriptor * @dev: the device whose string descriptor is being retrieved * @langid: code for language chosen (from string descriptor zero) * @index: the number of the descriptor * @buf: where to put the string * @size: how big is "buf"? * * Context: task context, might sleep. * * Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per character, * in little-endian byte order). * The usb_string() function will often be a convenient way to turn * these strings into kernel-printable form. * * Strings may be referenced in device, configuration, interface, or other * descriptors, and could also be used in vendor-specific ways. * * This call is synchronous, and may not be used in an interrupt context. * * Return: The number of bytes received on success, or else the status code * returned by the underlying usb_control_msg() call. */ static int usb_get_string(struct usb_device *dev, unsigned short langid, unsigned char index, void *buf, int size) { int i; int result; if (size <= 0) /* No point in asking for no data */ return -EINVAL; for (i = 0; i < 3; ++i) { /* retry on length 0 or stall; some devices are flakey */ result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), USB_REQ_GET_DESCRIPTOR, USB_DIR_IN, (USB_DT_STRING << 8) + index, langid, buf, size, USB_CTRL_GET_TIMEOUT); if (result == 0 || result == -EPIPE) continue; if (result > 1 && ((u8 *) buf)[1] != USB_DT_STRING) { result = -ENODATA; continue; } break; } return result; } static void usb_try_string_workarounds(unsigned char *buf, int *length) { int newlength, oldlength = *length; for (newlength = 2; newlength + 1 < oldlength; newlength += 2) if (!isprint(buf[newlength]) || buf[newlength + 1]) break; if (newlength > 2) { buf[0] = newlength; *length = newlength; } } static int usb_string_sub(struct usb_device *dev, unsigned int langid, unsigned int index, unsigned char *buf) { int rc; /* Try to read the string descriptor by asking for the maximum * possible number of bytes */ if (dev->quirks & USB_QUIRK_STRING_FETCH_255) rc = -EIO; else rc = usb_get_string(dev, langid, index, buf, 255); /* If that failed try to read the descriptor length, then * ask for just that many bytes */ if (rc < 2) { rc = usb_get_string(dev, langid, index, buf, 2); if (rc == 2) rc = usb_get_string(dev, langid, index, buf, buf[0]); } if (rc >= 2) { if (!buf[0] && !buf[1]) usb_try_string_workarounds(buf, &rc); /* There might be extra junk at the end of the descriptor */ if (buf[0] < rc) rc = buf[0]; rc = rc - (rc & 1); /* force a multiple of two */ } if (rc < 2) rc = (rc < 0 ? rc : -EINVAL); return rc; } static int usb_get_langid(struct usb_device *dev, unsigned char *tbuf) { int err; if (dev->have_langid) return 0; if (dev->string_langid < 0) return -EPIPE; err = usb_string_sub(dev, 0, 0, tbuf); /* If the string was reported but is malformed, default to english * (0x0409) */ if (err == -ENODATA || (err > 0 && err < 4)) { dev->string_langid = 0x0409; dev->have_langid = 1; dev_err(&dev->dev, "language id specifier not provided by device, defaulting to English\n"); return 0; } /* In case of all other errors, we assume the device is not able to * deal with strings at all. Set string_langid to -1 in order to * prevent any string to be retrieved from the device */ if (err < 0) { dev_info(&dev->dev, "string descriptor 0 read error: %d\n", err); dev->string_langid = -1; return -EPIPE; } /* always use the first langid listed */ dev->string_langid = tbuf[2] | (tbuf[3] << 8); dev->have_langid = 1; dev_dbg(&dev->dev, "default language 0x%04x\n", dev->string_langid); return 0; } /** * usb_string - returns UTF-8 version of a string descriptor * @dev: the device whose string descriptor is being retrieved * @index: the number of the descriptor * @buf: where to put the string * @size: how big is "buf"? * * Context: task context, might sleep. * * This converts the UTF-16LE encoded strings returned by devices, from * usb_get_string_descriptor(), to null-terminated UTF-8 encoded ones * that are more usable in most kernel contexts. Note that this function * chooses strings in the first language supported by the device. * * This call is synchronous, and may not be used in an interrupt context. * * Return: length of the string (>= 0) or usb_control_msg status (< 0). */ int usb_string(struct usb_device *dev, int index, char *buf, size_t size) { unsigned char *tbuf; int err; if (dev->state == USB_STATE_SUSPENDED) return -EHOSTUNREACH; if (size <= 0 || !buf) return -EINVAL; buf[0] = 0; if (index <= 0 || index >= 256) return -EINVAL; tbuf = kmalloc(256, GFP_NOIO); if (!tbuf) return -ENOMEM; err = usb_get_langid(dev, tbuf); if (err < 0) goto errout; err = usb_string_sub(dev, dev->string_langid, index, tbuf); if (err < 0) goto errout; size--; /* leave room for trailing NULL char in output buffer */ err = utf16s_to_utf8s((wchar_t *) &tbuf[2], (err - 2) / 2, UTF16_LITTLE_ENDIAN, buf, size); buf[err] = 0; if (tbuf[1] != USB_DT_STRING) dev_dbg(&dev->dev, "wrong descriptor type %02x for string %d (\"%s\")\n", tbuf[1], index, buf); errout: kfree(tbuf); return err; } EXPORT_SYMBOL_GPL(usb_string); /* one UTF-8-encoded 16-bit character has at most three bytes */ #define MAX_USB_STRING_SIZE (127 * 3 + 1) /** * usb_cache_string - read a string descriptor and cache it for later use * @udev: the device whose string descriptor is being read * @index: the descriptor index * * Return: A pointer to a kmalloc'ed buffer containing the descriptor string, * or %NULL if the index is 0 or the string could not be read. */ char *usb_cache_string(struct usb_device *udev, int index) { char *buf; char *smallbuf = NULL; int len; if (index <= 0) return NULL; buf = kmalloc(MAX_USB_STRING_SIZE, GFP_NOIO); if (buf) { len = usb_string(udev, index, buf, MAX_USB_STRING_SIZE); if (len > 0) { smallbuf = kmalloc(++len, GFP_NOIO); if (!smallbuf) return buf; memcpy(smallbuf, buf, len); } kfree(buf); } return smallbuf; } EXPORT_SYMBOL_GPL(usb_cache_string); /* * usb_get_device_descriptor - read the device descriptor * @udev: the device whose device descriptor should be read * * Context: task context, might sleep. * * Not exported, only for use by the core. If drivers really want to read * the device descriptor directly, they can call usb_get_descriptor() with * type = USB_DT_DEVICE and index = 0. * * Returns: a pointer to a dynamically allocated usb_device_descriptor * structure (which the caller must deallocate), or an ERR_PTR value. */ struct usb_device_descriptor *usb_get_device_descriptor(struct usb_device *udev) { struct usb_device_descriptor *desc; int ret; desc = kmalloc(sizeof(*desc), GFP_NOIO); if (!desc) return ERR_PTR(-ENOMEM); ret = usb_get_descriptor(udev, USB_DT_DEVICE, 0, desc, sizeof(*desc)); if (ret == sizeof(*desc)) return desc; if (ret >= 0) ret = -EMSGSIZE; kfree(desc); return ERR_PTR(ret); } /* * usb_set_isoch_delay - informs the device of the packet transmit delay * @dev: the device whose delay is to be informed * Context: task context, might sleep * * Since this is an optional request, we don't bother if it fails. */ int usb_set_isoch_delay(struct usb_device *dev) { /* skip hub devices */ if (dev->descriptor.bDeviceClass == USB_CLASS_HUB) return 0; /* skip non-SS/non-SSP devices */ if (dev->speed < USB_SPEED_SUPER) return 0; return usb_control_msg_send(dev, 0, USB_REQ_SET_ISOCH_DELAY, USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE, dev->hub_delay, 0, NULL, 0, USB_CTRL_SET_TIMEOUT, GFP_NOIO); } /** * usb_get_status - issues a GET_STATUS call * @dev: the device whose status is being checked * @recip: USB_RECIP_*; for device, interface, or endpoint * @type: USB_STATUS_TYPE_*; for standard or PTM status types * @target: zero (for device), else interface or endpoint number * @data: pointer to two bytes of bitmap data * * Context: task context, might sleep. * * Returns device, interface, or endpoint status. Normally only of * interest to see if the device is self powered, or has enabled the * remote wakeup facility; or whether a bulk or interrupt endpoint * is halted ("stalled"). * * Bits in these status bitmaps are set using the SET_FEATURE request, * and cleared using the CLEAR_FEATURE request. The usb_clear_halt() * function should be used to clear halt ("stall") status. * * This call is synchronous, and may not be used in an interrupt context. * * Returns 0 and the status value in *@data (in host byte order) on success, * or else the status code from the underlying usb_control_msg() call. */ int usb_get_status(struct usb_device *dev, int recip, int type, int target, void *data) { int ret; void *status; int length; switch (type) { case USB_STATUS_TYPE_STANDARD: length = 2; break; case USB_STATUS_TYPE_PTM: if (recip != USB_RECIP_DEVICE) return -EINVAL; length = 4; break; default: return -EINVAL; } status = kmalloc(length, GFP_KERNEL); if (!status) return -ENOMEM; ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), USB_REQ_GET_STATUS, USB_DIR_IN | recip, USB_STATUS_TYPE_STANDARD, target, status, length, USB_CTRL_GET_TIMEOUT); switch (ret) { case 4: if (type != USB_STATUS_TYPE_PTM) { ret = -EIO; break; } *(u32 *) data = le32_to_cpu(*(__le32 *) status); ret = 0; break; case 2: if (type != USB_STATUS_TYPE_STANDARD) { ret = -EIO; break; } *(u16 *) data = le16_to_cpu(*(__le16 *) status); ret = 0; break; default: ret = -EIO; } kfree(status); return ret; } EXPORT_SYMBOL_GPL(usb_get_status); /** * usb_clear_halt - tells device to clear endpoint halt/stall condition * @dev: device whose endpoint is halted * @pipe: endpoint "pipe" being cleared * * Context: task context, might sleep. * * This is used to clear halt conditions for bulk and interrupt endpoints, * as reported by URB completion status. Endpoints that are halted are * sometimes referred to as being "stalled". Such endpoints are unable * to transmit or receive data until the halt status is cleared. Any URBs * queued for such an endpoint should normally be unlinked by the driver * before clearing the halt condition, as described in sections 5.7.5 * and 5.8.5 of the USB 2.0 spec. * * Note that control and isochronous endpoints don't halt, although control * endpoints report "protocol stall" (for unsupported requests) using the * same status code used to report a true stall. * * This call is synchronous, and may not be used in an interrupt context. * If a thread in your driver uses this call, make sure your disconnect() * method can wait for it to complete. * * Return: Zero on success, or else the status code returned by the * underlying usb_control_msg() call. */ int usb_clear_halt(struct usb_device *dev, int pipe) { int result; int endp = usb_pipeendpoint(pipe); if (usb_pipein(pipe)) endp |= USB_DIR_IN; /* we don't care if it wasn't halted first. in fact some devices * (like some ibmcam model 1 units) seem to expect hosts to make * this request for iso endpoints, which can't halt! */ result = usb_control_msg_send(dev, 0, USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, USB_ENDPOINT_HALT, endp, NULL, 0, USB_CTRL_SET_TIMEOUT, GFP_NOIO); /* don't un-halt or force to DATA0 except on success */ if (result) return result; /* NOTE: seems like Microsoft and Apple don't bother verifying * the clear "took", so some devices could lock up if you check... * such as the Hagiwara FlashGate DUAL. So we won't bother. * * NOTE: make sure the logic here doesn't diverge much from * the copy in usb-storage, for as long as we need two copies. */ usb_reset_endpoint(dev, endp); return 0; } EXPORT_SYMBOL_GPL(usb_clear_halt); static int create_intf_ep_devs(struct usb_interface *intf) { struct usb_device *udev = interface_to_usbdev(intf); struct usb_host_interface *alt = intf->cur_altsetting; int i; if (intf->ep_devs_created || intf->unregistering) return 0; for (i = 0; i < alt->desc.bNumEndpoints; ++i) (void) usb_create_ep_devs(&intf->dev, &alt->endpoint[i], udev); intf->ep_devs_created = 1; return 0; } static void remove_intf_ep_devs(struct usb_interface *intf) { struct usb_host_interface *alt = intf->cur_altsetting; int i; if (!intf->ep_devs_created) return; for (i = 0; i < alt->desc.bNumEndpoints; ++i) usb_remove_ep_devs(&alt->endpoint[i]); intf->ep_devs_created = 0; } /** * usb_disable_endpoint -- Disable an endpoint by address * @dev: the device whose endpoint is being disabled * @epaddr: the endpoint's address. Endpoint number for output, * endpoint number + USB_DIR_IN for input * @reset_hardware: flag to erase any endpoint state stored in the * controller hardware * * Disables the endpoint for URB submission and nukes all pending URBs. * If @reset_hardware is set then also deallocates hcd/hardware state * for the endpoint. */ void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr, bool reset_hardware) { unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; struct usb_host_endpoint *ep; if (!dev) return; if (usb_endpoint_out(epaddr)) { ep = dev->ep_out[epnum]; if (reset_hardware && epnum != 0) dev->ep_out[epnum] = NULL; } else { ep = dev->ep_in[epnum]; if (reset_hardware && epnum != 0) dev->ep_in[epnum] = NULL; } if (ep) { ep->enabled = 0; usb_hcd_flush_endpoint(dev, ep); if (reset_hardware) usb_hcd_disable_endpoint(dev, ep); } } /** * usb_reset_endpoint - Reset an endpoint's state. * @dev: the device whose endpoint is to be reset * @epaddr: the endpoint's address. Endpoint number for output, * endpoint number + USB_DIR_IN for input * * Resets any host-side endpoint state such as the toggle bit, * sequence number or current window. */ void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr) { unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK; struct usb_host_endpoint *ep; if (usb_endpoint_out(epaddr)) ep = dev->ep_out[epnum]; else ep = dev->ep_in[epnum]; if (ep) usb_hcd_reset_endpoint(dev, ep); } EXPORT_SYMBOL_GPL(usb_reset_endpoint); /** * usb_disable_interface -- Disable all endpoints for an interface * @dev: the device whose interface is being disabled * @intf: pointer to the interface descriptor * @reset_hardware: flag to erase any endpoint state stored in the * controller hardware * * Disables all the endpoints for the interface's current altsetting. */ void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf, bool reset_hardware) { struct usb_host_interface *alt = intf->cur_altsetting; int i; for (i = 0; i < alt->desc.bNumEndpoints; ++i) { usb_disable_endpoint(dev, alt->endpoint[i].desc.bEndpointAddress, reset_hardware); } } /* * usb_disable_device_endpoints -- Disable all endpoints for a device * @dev: the device whose endpoints are being disabled * @skip_ep0: 0 to disable endpoint 0, 1 to skip it. */ static void usb_disable_device_endpoints(struct usb_device *dev, int skip_ep0) { struct usb_hcd *hcd = bus_to_hcd(dev->bus); int i; if (hcd->driver->check_bandwidth) { /* First pass: Cancel URBs, leave endpoint pointers intact. */ for (i = skip_ep0; i < 16; ++i) { usb_disable_endpoint(dev, i, false); usb_disable_endpoint(dev, i + USB_DIR_IN, false); } /* Remove endpoints from the host controller internal state */ mutex_lock(hcd->bandwidth_mutex); usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); mutex_unlock(hcd->bandwidth_mutex); } /* Second pass: remove endpoint pointers */ for (i = skip_ep0; i < 16; ++i) { usb_disable_endpoint(dev, i, true); usb_disable_endpoint(dev, i + USB_DIR_IN, true); } } /** * usb_disable_device - Disable all the endpoints for a USB device * @dev: the device whose endpoints are being disabled * @skip_ep0: 0 to disable endpoint 0, 1 to skip it. * * Disables all the device's endpoints, potentially including endpoint 0. * Deallocates hcd/hardware state for the endpoints (nuking all or most * pending urbs) and usbcore state for the interfaces, so that usbcore * must usb_set_configuration() before any interfaces could be used. */ void usb_disable_device(struct usb_device *dev, int skip_ep0) { int i; /* getting rid of interfaces will disconnect * any drivers bound to them (a key side effect) */ if (dev->actconfig) { /* * FIXME: In order to avoid self-deadlock involving the * bandwidth_mutex, we have to mark all the interfaces * before unregistering any of them. */ for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) dev->actconfig->interface[i]->unregistering = 1; for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { struct usb_interface *interface; /* remove this interface if it has been registered */ interface = dev->actconfig->interface[i]; if (!device_is_registered(&interface->dev)) continue; dev_dbg(&dev->dev, "unregistering interface %s\n", dev_name(&interface->dev)); remove_intf_ep_devs(interface); device_del(&interface->dev); } /* Now that the interfaces are unbound, nobody should * try to access them. */ for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) { put_device(&dev->actconfig->interface[i]->dev); dev->actconfig->interface[i] = NULL; } usb_disable_usb2_hardware_lpm(dev); usb_unlocked_disable_lpm(dev); usb_disable_ltm(dev); dev->actconfig = NULL; if (dev->state == USB_STATE_CONFIGURED) usb_set_device_state(dev, USB_STATE_ADDRESS); } dev_dbg(&dev->dev, "%s nuking %s URBs\n", __func__, skip_ep0 ? "non-ep0" : "all"); usb_disable_device_endpoints(dev, skip_ep0); } /** * usb_enable_endpoint - Enable an endpoint for USB communications * @dev: the device whose interface is being enabled * @ep: the endpoint * @reset_ep: flag to reset the endpoint state * * Resets the endpoint state if asked, and sets dev->ep_{in,out} pointers. * For control endpoints, both the input and output sides are handled. */ void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep, bool reset_ep) { int epnum = usb_endpoint_num(&ep->desc); int is_out = usb_endpoint_dir_out(&ep->desc); int is_control = usb_endpoint_xfer_control(&ep->desc); if (reset_ep) usb_hcd_reset_endpoint(dev, ep); if (is_out || is_control) dev->ep_out[epnum] = ep; if (!is_out || is_control) dev->ep_in[epnum] = ep; ep->enabled = 1; } /** * usb_enable_interface - Enable all the endpoints for an interface * @dev: the device whose interface is being enabled * @intf: pointer to the interface descriptor * @reset_eps: flag to reset the endpoints' state * * Enables all the endpoints for the interface's current altsetting. */ void usb_enable_interface(struct usb_device *dev, struct usb_interface *intf, bool reset_eps) { struct usb_host_interface *alt = intf->cur_altsetting; int i; for (i = 0; i < alt->desc.bNumEndpoints; ++i) usb_enable_endpoint(dev, &alt->endpoint[i], reset_eps); } /** * usb_set_interface - Makes a particular alternate setting be current * @dev: the device whose interface is being updated * @interface: the interface being updated * @alternate: the setting being chosen. * * Context: task context, might sleep. * * This is used to enable data transfers on interfaces that may not * be enabled by default. Not all devices support such configurability. * Only the driver bound to an interface may change its setting. * * Within any given configuration, each interface may have several * alternative settings. These are often used to control levels of * bandwidth consumption. For example, the default setting for a high * speed interrupt endpoint may not send more than 64 bytes per microframe, * while interrupt transfers of up to 3KBytes per microframe are legal. * Also, isochronous endpoints may never be part of an * interface's default setting. To access such bandwidth, alternate * interface settings must be made current. * * Note that in the Linux USB subsystem, bandwidth associated with * an endpoint in a given alternate setting is not reserved until an URB * is submitted that needs that bandwidth. Some other operating systems * allocate bandwidth early, when a configuration is chosen. * * xHCI reserves bandwidth and configures the alternate setting in * usb_hcd_alloc_bandwidth(). If it fails the original interface altsetting * may be disabled. Drivers cannot rely on any particular alternate * setting being in effect after a failure. * * This call is synchronous, and may not be used in an interrupt context. * Also, drivers must not change altsettings while urbs are scheduled for * endpoints in that interface; all such urbs must first be completed * (perhaps forced by unlinking). If a thread in your driver uses this call, * make sure your disconnect() method can wait for it to complete. * * Return: Zero on success, or else the status code returned by the * underlying usb_control_msg() call. */ int usb_set_interface(struct usb_device *dev, int interface, int alternate) { struct usb_interface *iface; struct usb_host_interface *alt; struct usb_hcd *hcd = bus_to_hcd(dev->bus); int i, ret, manual = 0; unsigned int epaddr; unsigned int pipe; if (dev->state == USB_STATE_SUSPENDED) return -EHOSTUNREACH; iface = usb_ifnum_to_if(dev, interface); if (!iface) { dev_dbg(&dev->dev, "selecting invalid interface %d\n", interface); return -EINVAL; } if (iface->unregistering) return -ENODEV; alt = usb_altnum_to_altsetting(iface, alternate); if (!alt) { dev_warn(&dev->dev, "selecting invalid altsetting %d\n", alternate); return -EINVAL; } /* * usb3 hosts configure the interface in usb_hcd_alloc_bandwidth, * including freeing dropped endpoint ring buffers. * Make sure the interface endpoints are flushed before that */ usb_disable_interface(dev, iface, false); /* Make sure we have enough bandwidth for this alternate interface. * Remove the current alt setting and add the new alt setting. */ mutex_lock(hcd->bandwidth_mutex); /* Disable LPM, and re-enable it once the new alt setting is installed, * so that the xHCI driver can recalculate the U1/U2 timeouts. */ if (usb_disable_lpm(dev)) { dev_err(&iface->dev, "%s Failed to disable LPM\n", __func__); mutex_unlock(hcd->bandwidth_mutex); return -ENOMEM; } /* Changing alt-setting also frees any allocated streams */ for (i = 0; i < iface->cur_altsetting->desc.bNumEndpoints; i++) iface->cur_altsetting->endpoint[i].streams = 0; ret = usb_hcd_alloc_bandwidth(dev, NULL, iface->cur_altsetting, alt); if (ret < 0) { dev_info(&dev->dev, "Not enough bandwidth for altsetting %d\n", alternate); usb_enable_lpm(dev); mutex_unlock(hcd->bandwidth_mutex); return ret; } if (dev->quirks & USB_QUIRK_NO_SET_INTF) ret = -EPIPE; else ret = usb_control_msg_send(dev, 0, USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE, alternate, interface, NULL, 0, 5000, GFP_NOIO); /* 9.4.10 says devices don't need this and are free to STALL the * request if the interface only has one alternate setting. */ if (ret == -EPIPE && iface->num_altsetting == 1) { dev_dbg(&dev->dev, "manual set_interface for iface %d, alt %d\n", interface, alternate); manual = 1; } else if (ret) { /* Re-instate the old alt setting */ usb_hcd_alloc_bandwidth(dev, NULL, alt, iface->cur_altsetting); usb_enable_lpm(dev); mutex_unlock(hcd->bandwidth_mutex); return ret; } mutex_unlock(hcd->bandwidth_mutex); /* FIXME drivers shouldn't need to replicate/bugfix the logic here * when they implement async or easily-killable versions of this or * other "should-be-internal" functions (like clear_halt). * should hcd+usbcore postprocess control requests? */ /* prevent submissions using previous endpoint settings */ if (iface->cur_altsetting != alt) { remove_intf_ep_devs(iface); usb_remove_sysfs_intf_files(iface); } usb_disable_interface(dev, iface, true); iface->cur_altsetting = alt; /* Now that the interface is installed, re-enable LPM. */ usb_unlocked_enable_lpm(dev); /* If the interface only has one altsetting and the device didn't * accept the request, we attempt to carry out the equivalent action * by manually clearing the HALT feature for each endpoint in the * new altsetting. */ if (manual) { for (i = 0; i < alt->desc.bNumEndpoints; i++) { epaddr = alt->endpoint[i].desc.bEndpointAddress; pipe = __create_pipe(dev, USB_ENDPOINT_NUMBER_MASK & epaddr) | (usb_endpoint_out(epaddr) ? USB_DIR_OUT : USB_DIR_IN); usb_clear_halt(dev, pipe); } } /* 9.1.1.5: reset toggles for all endpoints in the new altsetting * * Note: * Despite EP0 is always present in all interfaces/AS, the list of * endpoints from the descriptor does not contain EP0. Due to its * omnipresence one might expect EP0 being considered "affected" by * any SetInterface request and hence assume toggles need to be reset. * However, EP0 toggles are re-synced for every individual transfer * during the SETUP stage - hence EP0 toggles are "don't care" here. * (Likewise, EP0 never "halts" on well designed devices.) */ usb_enable_interface(dev, iface, true); if (device_is_registered(&iface->dev)) { usb_create_sysfs_intf_files(iface); create_intf_ep_devs(iface); } return 0; } EXPORT_SYMBOL_GPL(usb_set_interface); /** * usb_reset_configuration - lightweight device reset * @dev: the device whose configuration is being reset * * This issues a standard SET_CONFIGURATION request to the device using * the current configuration. The effect is to reset most USB-related * state in the device, including interface altsettings (reset to zero), * endpoint halts (cleared), and endpoint state (only for bulk and interrupt * endpoints). Other usbcore state is unchanged, including bindings of * usb device drivers to interfaces. * * Because this affects multiple interfaces, avoid using this with composite * (multi-interface) devices. Instead, the driver for each interface may * use usb_set_interface() on the interfaces it claims. Be careful though; * some devices don't support the SET_INTERFACE request, and others won't * reset all the interface state (notably endpoint state). Resetting the whole * configuration would affect other drivers' interfaces. * * The caller must own the device lock. * * Return: Zero on success, else a negative error code. * * If this routine fails the device will probably be in an unusable state * with endpoints disabled, and interfaces only partially enabled. */ int usb_reset_configuration(struct usb_device *dev) { int i, retval; struct usb_host_config *config; struct usb_hcd *hcd = bus_to_hcd(dev->bus); if (dev->state == USB_STATE_SUSPENDED) return -EHOSTUNREACH; /* caller must have locked the device and must own * the usb bus readlock (so driver bindings are stable); * calls during probe() are fine */ usb_disable_device_endpoints(dev, 1); /* skip ep0*/ config = dev->actconfig; retval = 0; mutex_lock(hcd->bandwidth_mutex); /* Disable LPM, and re-enable it once the configuration is reset, so * that the xHCI driver can recalculate the U1/U2 timeouts. */ if (usb_disable_lpm(dev)) { dev_err(&dev->dev, "%s Failed to disable LPM\n", __func__); mutex_unlock(hcd->bandwidth_mutex); return -ENOMEM; } /* xHCI adds all endpoints in usb_hcd_alloc_bandwidth */ retval = usb_hcd_alloc_bandwidth(dev, config, NULL, NULL); if (retval < 0) { usb_enable_lpm(dev); mutex_unlock(hcd->bandwidth_mutex); return retval; } retval = usb_control_msg_send(dev, 0, USB_REQ_SET_CONFIGURATION, 0, config->desc.bConfigurationValue, 0, NULL, 0, USB_CTRL_SET_TIMEOUT, GFP_NOIO); if (retval) { usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); usb_enable_lpm(dev); mutex_unlock(hcd->bandwidth_mutex); return retval; } mutex_unlock(hcd->bandwidth_mutex); /* re-init hc/hcd interface/endpoint state */ for (i = 0; i < config->desc.bNumInterfaces; i++) { struct usb_interface *intf = config->interface[i]; struct usb_host_interface *alt; alt = usb_altnum_to_altsetting(intf, 0); /* No altsetting 0? We'll assume the first altsetting. * We could use a GetInterface call, but if a device is * so non-compliant that it doesn't have altsetting 0 * then I wouldn't trust its reply anyway. */ if (!alt) alt = &intf->altsetting[0]; if (alt != intf->cur_altsetting) { remove_intf_ep_devs(intf); usb_remove_sysfs_intf_files(intf); } intf->cur_altsetting = alt; usb_enable_interface(dev, intf, true); if (device_is_registered(&intf->dev)) { usb_create_sysfs_intf_files(intf); create_intf_ep_devs(intf); } } /* Now that the interfaces are installed, re-enable LPM. */ usb_unlocked_enable_lpm(dev); return 0; } EXPORT_SYMBOL_GPL(usb_reset_configuration); static void usb_release_interface(struct device *dev) { struct usb_interface *intf = to_usb_interface(dev); struct usb_interface_cache *intfc = altsetting_to_usb_interface_cache(intf->altsetting); kref_put(&intfc->ref, usb_release_interface_cache); usb_put_dev(interface_to_usbdev(intf)); of_node_put(dev->of_node); kfree(intf); } /* * usb_deauthorize_interface - deauthorize an USB interface * * @intf: USB interface structure */ void usb_deauthorize_interface(struct usb_interface *intf) { struct device *dev = &intf->dev; device_lock(dev->parent); if (intf->authorized) { device_lock(dev); intf->authorized = 0; device_unlock(dev); usb_forced_unbind_intf(intf); } device_unlock(dev->parent); } /* * usb_authorize_interface - authorize an USB interface * * @intf: USB interface structure */ void usb_authorize_interface(struct usb_interface *intf) { struct device *dev = &intf->dev; if (!intf->authorized) { device_lock(dev); intf->authorized = 1; /* authorize interface */ device_unlock(dev); } } static int usb_if_uevent(const struct device *dev, struct kobj_uevent_env *env) { const struct usb_device *usb_dev; const struct usb_interface *intf; const struct usb_host_interface *alt; intf = to_usb_interface(dev); usb_dev = interface_to_usbdev(intf); alt = intf->cur_altsetting; if (add_uevent_var(env, "INTERFACE=%d/%d/%d", alt->desc.bInterfaceClass, alt->desc.bInterfaceSubClass, alt->desc.bInterfaceProtocol)) return -ENOMEM; if (add_uevent_var(env, "MODALIAS=usb:" "v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02Xin%02X", le16_to_cpu(usb_dev->descriptor.idVendor), le16_to_cpu(usb_dev->descriptor.idProduct), le16_to_cpu(usb_dev->descriptor.bcdDevice), usb_dev->descriptor.bDeviceClass, usb_dev->descriptor.bDeviceSubClass, usb_dev->descriptor.bDeviceProtocol, alt->desc.bInterfaceClass, alt->desc.bInterfaceSubClass, alt->desc.bInterfaceProtocol, alt->desc.bInterfaceNumber)) return -ENOMEM; return 0; } const struct device_type usb_if_device_type = { .name = "usb_interface", .release = usb_release_interface, .uevent = usb_if_uevent, }; static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev, struct usb_host_config *config, u8 inum) { struct usb_interface_assoc_descriptor *retval = NULL; struct usb_interface_assoc_descriptor *intf_assoc; int first_intf; int last_intf; int i; for (i = 0; (i < USB_MAXIADS && config->intf_assoc[i]); i++) { intf_assoc = config->intf_assoc[i]; if (intf_assoc->bInterfaceCount == 0) continue; first_intf = intf_assoc->bFirstInterface; last_intf = first_intf + (intf_assoc->bInterfaceCount - 1); if (inum >= first_intf && inum <= last_intf) { if (!retval) retval = intf_assoc; else dev_err(&dev->dev, "Interface #%d referenced" " by multiple IADs\n", inum); } } return retval; } /* * Internal function to queue a device reset * See usb_queue_reset_device() for more details */ static void __usb_queue_reset_device(struct work_struct *ws) { int rc; struct usb_interface *iface = container_of(ws, struct usb_interface, reset_ws); struct usb_device *udev = interface_to_usbdev(iface); rc = usb_lock_device_for_reset(udev, iface); if (rc >= 0) { usb_reset_device(udev); usb_unlock_device(udev); } usb_put_intf(iface); /* Undo _get_ in usb_queue_reset_device() */ } /* * Internal function to set the wireless_status sysfs attribute * See usb_set_wireless_status() for more details */ static void __usb_wireless_status_intf(struct work_struct *ws) { struct usb_interface *iface = container_of(ws, struct usb_interface, wireless_status_work); device_lock(iface->dev.parent); if (iface->sysfs_files_created) usb_update_wireless_status_attr(iface); device_unlock(iface->dev.parent); usb_put_intf(iface); /* Undo _get_ in usb_set_wireless_status() */ } /** * usb_set_wireless_status - sets the wireless_status struct member * @iface: the interface to modify * @status: the new wireless status * * Set the wireless_status struct member to the new value, and emit * sysfs changes as necessary. * * Returns: 0 on success, -EALREADY if already set. */ int usb_set_wireless_status(struct usb_interface *iface, enum usb_wireless_status status) { if (iface->wireless_status == status) return -EALREADY; usb_get_intf(iface); iface->wireless_status = status; schedule_work(&iface->wireless_status_work); return 0; } EXPORT_SYMBOL_GPL(usb_set_wireless_status); /* * usb_set_configuration - Makes a particular device setting be current * @dev: the device whose configuration is being updated * @configuration: the configuration being chosen. * * Context: task context, might sleep. Caller holds device lock. * * This is used to enable non-default device modes. Not all devices * use this kind of configurability; many devices only have one * configuration. * * @configuration is the value of the configuration to be installed. * According to the USB spec (e.g. section 9.1.1.5), configuration values * must be non-zero; a value of zero indicates that the device in * unconfigured. However some devices erroneously use 0 as one of their * configuration values. To help manage such devices, this routine will * accept @configuration = -1 as indicating the device should be put in * an unconfigured state. * * USB device configurations may affect Linux interoperability, * power consumption and the functionality available. For example, * the default configuration is limited to using 100mA of bus power, * so that when certain device functionality requires more power, * and the device is bus powered, that functionality should be in some * non-default device configuration. Other device modes may also be * reflected as configuration options, such as whether two ISDN * channels are available independently; and choosing between open * standard device protocols (like CDC) or proprietary ones. * * Note that a non-authorized device (dev->authorized == 0) will only * be put in unconfigured mode. * * Note that USB has an additional level of device configurability, * associated with interfaces. That configurability is accessed using * usb_set_interface(). * * This call is synchronous. The calling context must be able to sleep, * must own the device lock, and must not hold the driver model's USB * bus mutex; usb interface driver probe() methods cannot use this routine. * * Returns zero on success, or else the status code returned by the * underlying call that failed. On successful completion, each interface * in the original device configuration has been destroyed, and each one * in the new configuration has been probed by all relevant usb device * drivers currently known to the kernel. */ int usb_set_configuration(struct usb_device *dev, int configuration) { int i, ret; struct usb_host_config *cp = NULL; struct usb_interface **new_interfaces = NULL; struct usb_hcd *hcd = bus_to_hcd(dev->bus); int n, nintf; if (dev->authorized == 0 || configuration == -1) configuration = 0; else { for (i = 0; i < dev->descriptor.bNumConfigurations; i++) { if (dev->config[i].desc.bConfigurationValue == configuration) { cp = &dev->config[i]; break; } } } if ((!cp && configuration != 0)) return -EINVAL; /* The USB spec says configuration 0 means unconfigured. * But if a device includes a configuration numbered 0, * we will accept it as a correctly configured state. * Use -1 if you really want to unconfigure the device. */ if (cp && configuration == 0) dev_warn(&dev->dev, "config 0 descriptor??\n"); /* Allocate memory for new interfaces before doing anything else, * so that if we run out then nothing will have changed. */ n = nintf = 0; if (cp) { nintf = cp->desc.bNumInterfaces; new_interfaces = kmalloc_array(nintf, sizeof(*new_interfaces), GFP_NOIO); if (!new_interfaces) return -ENOMEM; for (; n < nintf; ++n) { new_interfaces[n] = kzalloc( sizeof(struct usb_interface), GFP_NOIO); if (!new_interfaces[n]) { ret = -ENOMEM; free_interfaces: while (--n >= 0) kfree(new_interfaces[n]); kfree(new_interfaces); return ret; } } i = dev->bus_mA - usb_get_max_power(dev, cp); if (i < 0) dev_warn(&dev->dev, "new config #%d exceeds power " "limit by %dmA\n", configuration, -i); } /* Wake up the device so we can send it the Set-Config request */ ret = usb_autoresume_device(dev); if (ret) goto free_interfaces; /* if it's already configured, clear out old state first. * getting rid of old interfaces means unbinding their drivers. */ if (dev->state != USB_STATE_ADDRESS) usb_disable_device(dev, 1); /* Skip ep0 */ /* Get rid of pending async Set-Config requests for this device */ cancel_async_set_config(dev); /* Make sure we have bandwidth (and available HCD resources) for this * configuration. Remove endpoints from the schedule if we're dropping * this configuration to set configuration 0. After this point, the * host controller will not allow submissions to dropped endpoints. If * this call fails, the device state is unchanged. */ mutex_lock(hcd->bandwidth_mutex); /* Disable LPM, and re-enable it once the new configuration is * installed, so that the xHCI driver can recalculate the U1/U2 * timeouts. */ if (dev->actconfig && usb_disable_lpm(dev)) { dev_err(&dev->dev, "%s Failed to disable LPM\n", __func__); mutex_unlock(hcd->bandwidth_mutex); ret = -ENOMEM; goto free_interfaces; } ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL); if (ret < 0) { if (dev->actconfig) usb_enable_lpm(dev); mutex_unlock(hcd->bandwidth_mutex); usb_autosuspend_device(dev); goto free_interfaces; } /* * Initialize the new interface structures and the * hc/hcd/usbcore interface/endpoint state. */ for (i = 0; i < nintf; ++i) { struct usb_interface_cache *intfc; struct usb_interface *intf; struct usb_host_interface *alt; u8 ifnum; cp->interface[i] = intf = new_interfaces[i]; intfc = cp->intf_cache[i]; intf->altsetting = intfc->altsetting; intf->num_altsetting = intfc->num_altsetting; intf->authorized = !!HCD_INTF_AUTHORIZED(hcd); kref_get(&intfc->ref); alt = usb_altnum_to_altsetting(intf, 0); /* No altsetting 0? We'll assume the first altsetting. * We could use a GetInterface call, but if a device is * so non-compliant that it doesn't have altsetting 0 * then I wouldn't trust its reply anyway. */ if (!alt) alt = &intf->altsetting[0]; ifnum = alt->desc.bInterfaceNumber; intf->intf_assoc = find_iad(dev, cp, ifnum); intf->cur_altsetting = alt; usb_enable_interface(dev, intf, true); intf->dev.parent = &dev->dev; if (usb_of_has_combined_node(dev)) { device_set_of_node_from_dev(&intf->dev, &dev->dev); } else { intf->dev.of_node = usb_of_get_interface_node(dev, configuration, ifnum); } ACPI_COMPANION_SET(&intf->dev, ACPI_COMPANION(&dev->dev)); intf->dev.driver = NULL; intf->dev.bus = &usb_bus_type; intf->dev.type = &usb_if_device_type; intf->dev.groups = usb_interface_groups; INIT_WORK(&intf->reset_ws, __usb_queue_reset_device); INIT_WORK(&intf->wireless_status_work, __usb_wireless_status_intf); intf->minor = -1; device_initialize(&intf->dev); pm_runtime_no_callbacks(&intf->dev); dev_set_name(&intf->dev, "%d-%s:%d.%d", dev->bus->busnum, dev->devpath, configuration, ifnum); usb_get_dev(dev); } kfree(new_interfaces); ret = usb_control_msg_send(dev, 0, USB_REQ_SET_CONFIGURATION, 0, configuration, 0, NULL, 0, USB_CTRL_SET_TIMEOUT, GFP_NOIO); if (ret && cp) { /* * All the old state is gone, so what else can we do? * The device is probably useless now anyway. */ usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL); for (i = 0; i < nintf; ++i) { usb_disable_interface(dev, cp->interface[i], true); put_device(&cp->interface[i]->dev); cp->interface[i] = NULL; } cp = NULL; } dev->actconfig = cp; mutex_unlock(hcd->bandwidth_mutex); if (!cp) { usb_set_device_state(dev, USB_STATE_ADDRESS); /* Leave LPM disabled while the device is unconfigured. */ usb_autosuspend_device(dev); return ret; } usb_set_device_state(dev, USB_STATE_CONFIGURED); if (cp->string == NULL && !(dev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS)) cp->string = usb_cache_string(dev, cp->desc.iConfiguration); /* Now that the interfaces are installed, re-enable LPM. */ usb_unlocked_enable_lpm(dev); /* Enable LTM if it was turned off by usb_disable_device. */ usb_enable_ltm(dev); /* Now that all the interfaces are set up, register them * to trigger binding of drivers to interfaces. probe() * routines may install different altsettings and may * claim() any interfaces not yet bound. Many class drivers * need that: CDC, audio, video, etc. */ for (i = 0; i < nintf; ++i) { struct usb_interface *intf = cp->interface[i]; if (intf->dev.of_node && !of_device_is_available(intf->dev.of_node)) { dev_info(&dev->dev, "skipping disabled interface %d\n", intf->cur_altsetting->desc.bInterfaceNumber); continue; } dev_dbg(&dev->dev, "adding %s (config #%d, interface %d)\n", dev_name(&intf->dev), configuration, intf->cur_altsetting->desc.bInterfaceNumber); device_enable_async_suspend(&intf->dev); ret = device_add(&intf->dev); if (ret != 0) { dev_err(&dev->dev, "device_add(%s) --> %d\n", dev_name(&intf->dev), ret); continue; } create_intf_ep_devs(intf); } usb_autosuspend_device(dev); return 0; } EXPORT_SYMBOL_GPL(usb_set_configuration); static LIST_HEAD(set_config_list); static DEFINE_SPINLOCK(set_config_lock); struct set_config_request { struct usb_device *udev; int config; struct work_struct work; struct list_head node; }; /* Worker routine for usb_driver_set_configuration() */ static void driver_set_config_work(struct work_struct *work) { struct set_config_request *req = container_of(work, struct set_config_request, work); struct usb_device *udev = req->udev; usb_lock_device(udev); spin_lock(&set_config_lock); list_del(&req->node); spin_unlock(&set_config_lock); if (req->config >= -1) /* Is req still valid? */ usb_set_configuration(udev, req->config); usb_unlock_device(udev); usb_put_dev(udev); kfree(req); } /* Cancel pending Set-Config requests for a device whose configuration * was just changed */ static void cancel_async_set_config(struct usb_device *udev) { struct set_config_request *req; spin_lock(&set_config_lock); list_for_each_entry(req, &set_config_list, node) { if (req->udev == udev) req->config = -999; /* Mark as cancelled */ } spin_unlock(&set_config_lock); } /** * usb_driver_set_configuration - Provide a way for drivers to change device configurations * @udev: the device whose configuration is being updated * @config: the configuration being chosen. * Context: In process context, must be able to sleep * * Device interface drivers are not allowed to change device configurations. * This is because changing configurations will destroy the interface the * driver is bound to and create new ones; it would be like a floppy-disk * driver telling the computer to replace the floppy-disk drive with a * tape drive! * * Still, in certain specialized circumstances the need may arise. This * routine gets around the normal restrictions by using a work thread to * submit the change-config request. * * Return: 0 if the request was successfully queued, error code otherwise. * The caller has no way to know whether the queued request will eventually * succeed. */ int usb_driver_set_configuration(struct usb_device *udev, int config) { struct set_config_request *req; req = kmalloc(sizeof(*req), GFP_KERNEL); if (!req) return -ENOMEM; req->udev = udev; req->config = config; INIT_WORK(&req->work, driver_set_config_work); spin_lock(&set_config_lock); list_add(&req->node, &set_config_list); spin_unlock(&set_config_lock); usb_get_dev(udev); schedule_work(&req->work); return 0; } EXPORT_SYMBOL_GPL(usb_driver_set_configuration); /** * cdc_parse_cdc_header - parse the extra headers present in CDC devices * @hdr: the place to put the results of the parsing * @intf: the interface for which parsing is requested * @buffer: pointer to the extra headers to be parsed * @buflen: length of the extra headers * * This evaluates the extra headers present in CDC devices which * bind the interfaces for data and control and provide details * about the capabilities of the device. * * Return: number of descriptors parsed or -EINVAL * if the header is contradictory beyond salvage */ int cdc_parse_cdc_header(struct usb_cdc_parsed_header *hdr, struct usb_interface *intf, u8 *buffer, int buflen) { /* duplicates are ignored */ struct usb_cdc_union_desc *union_header = NULL; /* duplicates are not tolerated */ struct usb_cdc_header_desc *header = NULL; struct usb_cdc_ether_desc *ether = NULL; struct usb_cdc_mdlm_detail_desc *detail = NULL; struct usb_cdc_mdlm_desc *desc = NULL; unsigned int elength; int cnt = 0; memset(hdr, 0x00, sizeof(struct usb_cdc_parsed_header)); hdr->phonet_magic_present = false; while (buflen > 0) { elength = buffer[0]; if (!elength) { dev_err(&intf->dev, "skipping garbage byte\n"); elength = 1; goto next_desc; } if ((buflen < elength) || (elength < 3)) { dev_err(&intf->dev, "invalid descriptor buffer length\n"); break; } if (buffer[1] != USB_DT_CS_INTERFACE) { dev_err(&intf->dev, "skipping garbage\n"); goto next_desc; } switch (buffer[2]) { case USB_CDC_UNION_TYPE: /* we've found it */ if (elength < sizeof(struct usb_cdc_union_desc)) goto next_desc; if (union_header) { dev_err(&intf->dev, "More than one union descriptor, skipping ...\n"); goto next_desc; } union_header = (struct usb_cdc_union_desc *)buffer; break; case USB_CDC_COUNTRY_TYPE: if (elength < sizeof(struct usb_cdc_country_functional_desc)) goto next_desc; hdr->usb_cdc_country_functional_desc = (struct usb_cdc_country_functional_desc *)buffer; break; case USB_CDC_HEADER_TYPE: if (elength != sizeof(struct usb_cdc_header_desc)) goto next_desc; if (header) return -EINVAL; header = (struct usb_cdc_header_desc *)buffer; break; case USB_CDC_ACM_TYPE: if (elength < sizeof(struct usb_cdc_acm_descriptor)) goto next_desc; hdr->usb_cdc_acm_descriptor = (struct usb_cdc_acm_descriptor *)buffer; break; case USB_CDC_ETHERNET_TYPE: if (elength != sizeof(struct usb_cdc_ether_desc)) goto next_desc; if (ether) return -EINVAL; ether = (struct usb_cdc_ether_desc *)buffer; break; case USB_CDC_CALL_MANAGEMENT_TYPE: if (elength < sizeof(struct usb_cdc_call_mgmt_descriptor)) goto next_desc; hdr->usb_cdc_call_mgmt_descriptor = (struct usb_cdc_call_mgmt_descriptor *)buffer; break; case USB_CDC_DMM_TYPE: if (elength < sizeof(struct usb_cdc_dmm_desc)) goto next_desc; hdr->usb_cdc_dmm_desc = (struct usb_cdc_dmm_desc *)buffer; break; case USB_CDC_MDLM_TYPE: if (elength < sizeof(struct usb_cdc_mdlm_desc)) goto next_desc; if (desc) return -EINVAL; desc = (struct usb_cdc_mdlm_desc *)buffer; break; case USB_CDC_MDLM_DETAIL_TYPE: if (elength < sizeof(struct usb_cdc_mdlm_detail_desc)) goto next_desc; if (detail) return -EINVAL; detail = (struct usb_cdc_mdlm_detail_desc *)buffer; break; case USB_CDC_NCM_TYPE: if (elength < sizeof(struct usb_cdc_ncm_desc)) goto next_desc; hdr->usb_cdc_ncm_desc = (struct usb_cdc_ncm_desc *)buffer; break; case USB_CDC_MBIM_TYPE: if (elength < sizeof(struct usb_cdc_mbim_desc)) goto next_desc; hdr->usb_cdc_mbim_desc = (struct usb_cdc_mbim_desc *)buffer; break; case USB_CDC_MBIM_EXTENDED_TYPE: if (elength < sizeof(struct usb_cdc_mbim_extended_desc)) break; hdr->usb_cdc_mbim_extended_desc = (struct usb_cdc_mbim_extended_desc *)buffer; break; case CDC_PHONET_MAGIC_NUMBER: hdr->phonet_magic_present = true; break; default: /* * there are LOTS more CDC descriptors that * could legitimately be found here. */ dev_dbg(&intf->dev, "Ignoring descriptor: type %02x, length %ud\n", buffer[2], elength); goto next_desc; } cnt++; next_desc: buflen -= elength; buffer += elength; } hdr->usb_cdc_union_desc = union_header; hdr->usb_cdc_header_desc = header; hdr->usb_cdc_mdlm_detail_desc = detail; hdr->usb_cdc_mdlm_desc = desc; hdr->usb_cdc_ether_desc = ether; return cnt; } EXPORT_SYMBOL(cdc_parse_cdc_header);
20 25 20 20 20 19 19 19 19 25 25 25 19 19 19 18 16 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 // SPDX-License-Identifier: GPL-2.0-or-later /* * Device management routines * Copyright (c) by Jaroslav Kysela <perex@perex.cz> */ #include <linux/slab.h> #include <linux/time.h> #include <linux/export.h> #include <linux/errno.h> #include <sound/core.h> /** * snd_device_new - create an ALSA device component * @card: the card instance * @type: the device type, SNDRV_DEV_XXX * @device_data: the data pointer of this device * @ops: the operator table * * Creates a new device component for the given data pointer. * The device will be assigned to the card and managed together * by the card. * * The data pointer plays a role as the identifier, too, so the * pointer address must be unique and unchanged. * * Return: Zero if successful, or a negative error code on failure. */ int snd_device_new(struct snd_card *card, enum snd_device_type type, void *device_data, const struct snd_device_ops *ops) { struct snd_device *dev; struct list_head *p; if (snd_BUG_ON(!card || !device_data || !ops)) return -ENXIO; dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (!dev) return -ENOMEM; INIT_LIST_HEAD(&dev->list); dev->card = card; dev->type = type; dev->state = SNDRV_DEV_BUILD; dev->device_data = device_data; dev->ops = ops; /* insert the entry in an incrementally sorted list */ list_for_each_prev(p, &card->devices) { struct snd_device *pdev = list_entry(p, struct snd_device, list); if ((unsigned int)pdev->type <= (unsigned int)type) break; } list_add(&dev->list, p); return 0; } EXPORT_SYMBOL(snd_device_new); static void __snd_device_disconnect(struct snd_device *dev) { if (dev->state == SNDRV_DEV_REGISTERED) { if (dev->ops->dev_disconnect && dev->ops->dev_disconnect(dev)) dev_err(dev->card->dev, "device disconnect failure\n"); dev->state = SNDRV_DEV_DISCONNECTED; } } static void __snd_device_free(struct snd_device *dev) { /* unlink */ list_del(&dev->list); __snd_device_disconnect(dev); if (dev->ops->dev_free) { if (dev->ops->dev_free(dev)) dev_err(dev->card->dev, "device free failure\n"); } kfree(dev); } static struct snd_device *look_for_dev(struct snd_card *card, void *device_data) { struct snd_device *dev; list_for_each_entry(dev, &card->devices, list) if (dev->device_data == device_data) return dev; return NULL; } /** * snd_device_disconnect - disconnect the device * @card: the card instance * @device_data: the data pointer to disconnect * * Turns the device into the disconnection state, invoking * dev_disconnect callback, if the device was already registered. * * Usually called from snd_card_disconnect(). * * Return: Zero if successful, or a negative error code on failure or if the * device not found. */ void snd_device_disconnect(struct snd_card *card, void *device_data) { struct snd_device *dev; if (snd_BUG_ON(!card || !device_data)) return; dev = look_for_dev(card, device_data); if (dev) __snd_device_disconnect(dev); else dev_dbg(card->dev, "device disconnect %p (from %pS), not found\n", device_data, __builtin_return_address(0)); } EXPORT_SYMBOL_GPL(snd_device_disconnect); /** * snd_device_free - release the device from the card * @card: the card instance * @device_data: the data pointer to release * * Removes the device from the list on the card and invokes the * callbacks, dev_disconnect and dev_free, corresponding to the state. * Then release the device. */ void snd_device_free(struct snd_card *card, void *device_data) { struct snd_device *dev; if (snd_BUG_ON(!card || !device_data)) return; dev = look_for_dev(card, device_data); if (dev) __snd_device_free(dev); else dev_dbg(card->dev, "device free %p (from %pS), not found\n", device_data, __builtin_return_address(0)); } EXPORT_SYMBOL(snd_device_free); static int __snd_device_register(struct snd_device *dev) { if (dev->state == SNDRV_DEV_BUILD) { if (dev->ops->dev_register) { int err = dev->ops->dev_register(dev); if (err < 0) return err; } dev->state = SNDRV_DEV_REGISTERED; } return 0; } /** * snd_device_register - register the device * @card: the card instance * @device_data: the data pointer to register * * Registers the device which was already created via * snd_device_new(). Usually this is called from snd_card_register(), * but it can be called later if any new devices are created after * invocation of snd_card_register(). * * Return: Zero if successful, or a negative error code on failure or if the * device not found. */ int snd_device_register(struct snd_card *card, void *device_data) { struct snd_device *dev; if (snd_BUG_ON(!card || !device_data)) return -ENXIO; dev = look_for_dev(card, device_data); if (dev) return __snd_device_register(dev); snd_BUG(); return -ENXIO; } EXPORT_SYMBOL(snd_device_register); /* * register all the devices on the card. * called from init.c */ int snd_device_register_all(struct snd_card *card) { struct snd_device *dev; int err; if (snd_BUG_ON(!card)) return -ENXIO; list_for_each_entry(dev, &card->devices, list) { err = __snd_device_register(dev); if (err < 0) return err; } return 0; } /* * disconnect all the devices on the card. * called from init.c */ void snd_device_disconnect_all(struct snd_card *card) { struct snd_device *dev; if (snd_BUG_ON(!card)) return; list_for_each_entry_reverse(dev, &card->devices, list) __snd_device_disconnect(dev); } /* * release all the devices on the card. * called from init.c */ void snd_device_free_all(struct snd_card *card) { struct snd_device *dev, *next; if (snd_BUG_ON(!card)) return; list_for_each_entry_safe_reverse(dev, next, &card->devices, list) { /* exception: free ctl and lowlevel stuff later */ if (dev->type == SNDRV_DEV_CONTROL || dev->type == SNDRV_DEV_LOWLEVEL) continue; __snd_device_free(dev); } /* free all */ list_for_each_entry_safe_reverse(dev, next, &card->devices, list) __snd_device_free(dev); } /** * snd_device_get_state - Get the current state of the given device * @card: the card instance * @device_data: the data pointer to release * * Returns the current state of the given device object. For the valid * device, either @SNDRV_DEV_BUILD, @SNDRV_DEV_REGISTERED or * @SNDRV_DEV_DISCONNECTED is returned. * Or for a non-existing device, -1 is returned as an error. * * Return: the current state, or -1 if not found */ int snd_device_get_state(struct snd_card *card, void *device_data) { struct snd_device *dev; dev = look_for_dev(card, device_data); if (dev) return dev->state; return -1; } EXPORT_SYMBOL_GPL(snd_device_get_state);
1 1 2 2 1 1 1 1 1 1 1 1 1 29 1 1 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 // SPDX-License-Identifier: GPL-2.0-or-later /* * Force feedback support for Linux input subsystem * * Copyright (c) 2006 Anssi Hannula <anssi.hannula@gmail.com> * Copyright (c) 2006 Dmitry Torokhov <dtor@mail.ru> */ /* #define DEBUG */ #include <linux/input.h> #include <linux/limits.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/overflow.h> #include <linux/sched.h> #include <linux/slab.h> /* * Check that the effect_id is a valid effect and whether the user * is the owner */ static int check_effect_access(struct ff_device *ff, int effect_id, struct file *file) { if (effect_id < 0 || effect_id >= ff->max_effects || !ff->effect_owners[effect_id]) return -EINVAL; if (file && ff->effect_owners[effect_id] != file) return -EACCES; return 0; } /* * Checks whether 2 effects can be combined together */ static inline int check_effects_compatible(struct ff_effect *e1, struct ff_effect *e2) { return e1->type == e2->type && (e1->type != FF_PERIODIC || e1->u.periodic.waveform == e2->u.periodic.waveform); } /* * Convert an effect into compatible one */ static int compat_effect(struct ff_device *ff, struct ff_effect *effect) { int magnitude; switch (effect->type) { case FF_RUMBLE: if (!test_bit(FF_PERIODIC, ff->ffbit)) return -EINVAL; /* * calculate magnitude of sine wave as average of rumble's * 2/3 of strong magnitude and 1/3 of weak magnitude */ magnitude = effect->u.rumble.strong_magnitude / 3 + effect->u.rumble.weak_magnitude / 6; effect->type = FF_PERIODIC; effect->u.periodic.waveform = FF_SINE; effect->u.periodic.period = 50; effect->u.periodic.magnitude = magnitude; effect->u.periodic.offset = 0; effect->u.periodic.phase = 0; effect->u.periodic.envelope.attack_length = 0; effect->u.periodic.envelope.attack_level = 0; effect->u.periodic.envelope.fade_length = 0; effect->u.periodic.envelope.fade_level = 0; return 0; default: /* Let driver handle conversion */ return 0; } } /** * input_ff_upload() - upload effect into force-feedback device * @dev: input device * @effect: effect to be uploaded * @file: owner of the effect */ int input_ff_upload(struct input_dev *dev, struct ff_effect *effect, struct file *file) { struct ff_device *ff = dev->ff; struct ff_effect *old; int ret = 0; int id; if (!test_bit(EV_FF, dev->evbit)) return -ENOSYS; if (effect->type < FF_EFFECT_MIN || effect->type > FF_EFFECT_MAX || !test_bit(effect->type, dev->ffbit)) { dev_dbg(&dev->dev, "invalid or not supported effect type in upload\n"); return -EINVAL; } if (effect->type == FF_PERIODIC && (effect->u.periodic.waveform < FF_WAVEFORM_MIN || effect->u.periodic.waveform > FF_WAVEFORM_MAX || !test_bit(effect->u.periodic.waveform, dev->ffbit))) { dev_dbg(&dev->dev, "invalid or not supported wave form in upload\n"); return -EINVAL; } if (!test_bit(effect->type, ff->ffbit)) { ret = compat_effect(ff, effect); if (ret) return ret; } mutex_lock(&ff->mutex); if (effect->id == -1) { for (id = 0; id < ff->max_effects; id++) if (!ff->effect_owners[id]) break; if (id >= ff->max_effects) { ret = -ENOSPC; goto out; } effect->id = id; old = NULL; } else { id = effect->id; ret = check_effect_access(ff, id, file); if (ret) goto out; old = &ff->effects[id]; if (!check_effects_compatible(effect, old)) { ret = -EINVAL; goto out; } } ret = ff->upload(dev, effect, old); if (ret) goto out; spin_lock_irq(&dev->event_lock); ff->effects[id] = *effect; ff->effect_owners[id] = file; spin_unlock_irq(&dev->event_lock); out: mutex_unlock(&ff->mutex); return ret; } EXPORT_SYMBOL_GPL(input_ff_upload); /* * Erases the effect if the requester is also the effect owner. The mutex * should already be locked before calling this function. */ static int erase_effect(struct input_dev *dev, int effect_id, struct file *file) { struct ff_device *ff = dev->ff; int error; error = check_effect_access(ff, effect_id, file); if (error) return error; spin_lock_irq(&dev->event_lock); ff->playback(dev, effect_id, 0); ff->effect_owners[effect_id] = NULL; spin_unlock_irq(&dev->event_lock); if (ff->erase) { error = ff->erase(dev, effect_id); if (error) { spin_lock_irq(&dev->event_lock); ff->effect_owners[effect_id] = file; spin_unlock_irq(&dev->event_lock); return error; } } return 0; } /** * input_ff_erase - erase a force-feedback effect from device * @dev: input device to erase effect from * @effect_id: id of the effect to be erased * @file: purported owner of the request * * This function erases a force-feedback effect from specified device. * The effect will only be erased if it was uploaded through the same * file handle that is requesting erase. */ int input_ff_erase(struct input_dev *dev, int effect_id, struct file *file) { struct ff_device *ff = dev->ff; int ret; if (!test_bit(EV_FF, dev->evbit)) return -ENOSYS; mutex_lock(&ff->mutex); ret = erase_effect(dev, effect_id, file); mutex_unlock(&ff->mutex); return ret; } EXPORT_SYMBOL_GPL(input_ff_erase); /* * input_ff_flush - erase all effects owned by a file handle * @dev: input device to erase effect from * @file: purported owner of the effects * * This function erases all force-feedback effects associated with * the given owner from specified device. Note that @file may be %NULL, * in which case all effects will be erased. */ int input_ff_flush(struct input_dev *dev, struct file *file) { struct ff_device *ff = dev->ff; int i; dev_dbg(&dev->dev, "flushing now\n"); mutex_lock(&ff->mutex); for (i = 0; i < ff->max_effects; i++) erase_effect(dev, i, file); mutex_unlock(&ff->mutex); return 0; } EXPORT_SYMBOL_GPL(input_ff_flush); /** * input_ff_event() - generic handler for force-feedback events * @dev: input device to send the effect to * @type: event type (anything but EV_FF is ignored) * @code: event code * @value: event value */ int input_ff_event(struct input_dev *dev, unsigned int type, unsigned int code, int value) { struct ff_device *ff = dev->ff; if (type != EV_FF) return 0; switch (code) { case FF_GAIN: if (!test_bit(FF_GAIN, dev->ffbit) || value > 0xffffU) break; ff->set_gain(dev, value); break; case FF_AUTOCENTER: if (!test_bit(FF_AUTOCENTER, dev->ffbit) || value > 0xffffU) break; ff->set_autocenter(dev, value); break; default: if (check_effect_access(ff, code, NULL) == 0) ff->playback(dev, code, value); break; } return 0; } EXPORT_SYMBOL_GPL(input_ff_event); /** * input_ff_create() - create force-feedback device * @dev: input device supporting force-feedback * @max_effects: maximum number of effects supported by the device * * This function allocates all necessary memory for a force feedback * portion of an input device and installs all default handlers. * @dev->ffbit should be already set up before calling this function. * Once ff device is created you need to setup its upload, erase, * playback and other handlers before registering input device */ int input_ff_create(struct input_dev *dev, unsigned int max_effects) { struct ff_device *ff; size_t ff_dev_size; int i; if (!max_effects) { dev_err(&dev->dev, "cannot allocate device without any effects\n"); return -EINVAL; } if (max_effects > FF_MAX_EFFECTS) { dev_err(&dev->dev, "cannot allocate more than FF_MAX_EFFECTS effects\n"); return -EINVAL; } ff_dev_size = struct_size(ff, effect_owners, max_effects); if (ff_dev_size == SIZE_MAX) /* overflow */ return -EINVAL; ff = kzalloc(ff_dev_size, GFP_KERNEL); if (!ff) return -ENOMEM; ff->effects = kcalloc(max_effects, sizeof(struct ff_effect), GFP_KERNEL); if (!ff->effects) { kfree(ff); return -ENOMEM; } ff->max_effects = max_effects; mutex_init(&ff->mutex); dev->ff = ff; dev->flush = input_ff_flush; dev->event = input_ff_event; __set_bit(EV_FF, dev->evbit); /* Copy "true" bits into ff device bitmap */ for_each_set_bit(i, dev->ffbit, FF_CNT) __set_bit(i, ff->ffbit); /* we can emulate RUMBLE with periodic effects */ if (test_bit(FF_PERIODIC, ff->ffbit)) __set_bit(FF_RUMBLE, dev->ffbit); return 0; } EXPORT_SYMBOL_GPL(input_ff_create); /** * input_ff_destroy() - frees force feedback portion of input device * @dev: input device supporting force feedback * * This function is only needed in error path as input core will * automatically free force feedback structures when device is * destroyed. */ void input_ff_destroy(struct input_dev *dev) { struct ff_device *ff = dev->ff; __clear_bit(EV_FF, dev->evbit); if (ff) { if (ff->destroy) ff->destroy(ff); kfree(ff->private); kfree(ff->effects); kfree(ff); dev->ff = NULL; } } EXPORT_SYMBOL_GPL(input_ff_destroy);
3 3 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 /* SPDX-License-Identifier: GPL-2.0-or-later * * Copyright (C) 2005 David Brownell */ #ifndef __LINUX_SPI_H #define __LINUX_SPI_H #include <linux/acpi.h> #include <linux/bits.h> #include <linux/completion.h> #include <linux/device.h> #include <linux/gpio/consumer.h> #include <linux/kthread.h> #include <linux/mod_devicetable.h> #include <linux/overflow.h> #include <linux/scatterlist.h> #include <linux/slab.h> #include <linux/u64_stats_sync.h> #include <uapi/linux/spi/spi.h> /* Max no. of CS supported per spi device */ #define SPI_CS_CNT_MAX 16 struct dma_chan; struct software_node; struct ptp_system_timestamp; struct spi_controller; struct spi_transfer; struct spi_controller_mem_ops; struct spi_controller_mem_caps; struct spi_message; /* * INTERFACES between SPI master-side drivers and SPI slave protocol handlers, * and SPI infrastructure. */ extern const struct bus_type spi_bus_type; /** * struct spi_statistics - statistics for spi transfers * @syncp: seqcount to protect members in this struct for per-cpu update * on 32-bit systems * * @messages: number of spi-messages handled * @transfers: number of spi_transfers handled * @errors: number of errors during spi_transfer * @timedout: number of timeouts during spi_transfer * * @spi_sync: number of times spi_sync is used * @spi_sync_immediate: * number of times spi_sync is executed immediately * in calling context without queuing and scheduling * @spi_async: number of times spi_async is used * * @bytes: number of bytes transferred to/from device * @bytes_tx: number of bytes sent to device * @bytes_rx: number of bytes received from device * * @transfer_bytes_histo: * transfer bytes histogram * * @transfers_split_maxsize: * number of transfers that have been split because of * maxsize limit */ struct spi_statistics { struct u64_stats_sync syncp; u64_stats_t messages; u64_stats_t transfers; u64_stats_t errors; u64_stats_t timedout; u64_stats_t spi_sync; u64_stats_t spi_sync_immediate; u64_stats_t spi_async; u64_stats_t bytes; u64_stats_t bytes_rx; u64_stats_t bytes_tx; #define SPI_STATISTICS_HISTO_SIZE 17 u64_stats_t transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE]; u64_stats_t transfers_split_maxsize; }; #define SPI_STATISTICS_ADD_TO_FIELD(pcpu_stats, field, count) \ do { \ struct spi_statistics *__lstats; \ get_cpu(); \ __lstats = this_cpu_ptr(pcpu_stats); \ u64_stats_update_begin(&__lstats->syncp); \ u64_stats_add(&__lstats->field, count); \ u64_stats_update_end(&__lstats->syncp); \ put_cpu(); \ } while (0) #define SPI_STATISTICS_INCREMENT_FIELD(pcpu_stats, field) \ do { \ struct spi_statistics *__lstats; \ get_cpu(); \ __lstats = this_cpu_ptr(pcpu_stats); \ u64_stats_update_begin(&__lstats->syncp); \ u64_stats_inc(&__lstats->field); \ u64_stats_update_end(&__lstats->syncp); \ put_cpu(); \ } while (0) /** * struct spi_delay - SPI delay information * @value: Value for the delay * @unit: Unit for the delay */ struct spi_delay { #define SPI_DELAY_UNIT_USECS 0 #define SPI_DELAY_UNIT_NSECS 1 #define SPI_DELAY_UNIT_SCK 2 u16 value; u8 unit; }; extern int spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer); extern int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer); extern void spi_transfer_cs_change_delay_exec(struct spi_message *msg, struct spi_transfer *xfer); /** * struct spi_device - Controller side proxy for an SPI slave device * @dev: Driver model representation of the device. * @controller: SPI controller used with the device. * @max_speed_hz: Maximum clock rate to be used with this chip * (on this board); may be changed by the device's driver. * The spi_transfer.speed_hz can override this for each transfer. * @chip_select: Array of physical chipselect, spi->chipselect[i] gives * the corresponding physical CS for logical CS i. * @mode: The spi mode defines how data is clocked out and in. * This may be changed by the device's driver. * The "active low" default for chipselect mode can be overridden * (by specifying SPI_CS_HIGH) as can the "MSB first" default for * each word in a transfer (by specifying SPI_LSB_FIRST). * @bits_per_word: Data transfers involve one or more words; word sizes * like eight or 12 bits are common. In-memory wordsizes are * powers of two bytes (e.g. 20 bit samples use 32 bits). * This may be changed by the device's driver, or left at the * default (0) indicating protocol words are eight bit bytes. * The spi_transfer.bits_per_word can override this for each transfer. * @rt: Make the pump thread real time priority. * @irq: Negative, or the number passed to request_irq() to receive * interrupts from this device. * @controller_state: Controller's runtime state * @controller_data: Board-specific definitions for controller, such as * FIFO initialization parameters; from board_info.controller_data * @modalias: Name of the driver to use with this device, or an alias * for that name. This appears in the sysfs "modalias" attribute * for driver coldplugging, and in uevents used for hotplugging * @driver_override: If the name of a driver is written to this attribute, then * the device will bind to the named driver and only the named driver. * Do not set directly, because core frees it; use driver_set_override() to * set or clear it. * @cs_gpiod: Array of GPIO descriptors of the corresponding chipselect lines * (optional, NULL when not using a GPIO line) * @word_delay: delay to be inserted between consecutive * words of a transfer * @cs_setup: delay to be introduced by the controller after CS is asserted * @cs_hold: delay to be introduced by the controller before CS is deasserted * @cs_inactive: delay to be introduced by the controller after CS is * deasserted. If @cs_change_delay is used from @spi_transfer, then the * two delays will be added up. * @pcpu_statistics: statistics for the spi_device * @cs_index_mask: Bit mask of the active chipselect(s) in the chipselect array * * A @spi_device is used to interchange data between an SPI slave * (usually a discrete chip) and CPU memory. * * In @dev, the platform_data is used to hold information about this * device that's meaningful to the device's protocol driver, but not * to its controller. One example might be an identifier for a chip * variant with slightly different functionality; another might be * information about how this particular board wires the chip's pins. */ struct spi_device { struct device dev; struct spi_controller *controller; u32 max_speed_hz; u8 chip_select[SPI_CS_CNT_MAX]; u8 bits_per_word; bool rt; #define SPI_NO_TX BIT(31) /* No transmit wire */ #define SPI_NO_RX BIT(30) /* No receive wire */ /* * TPM specification defines flow control over SPI. Client device * can insert a wait state on MISO when address is transmitted by * controller on MOSI. Detecting the wait state in software is only * possible for full duplex controllers. For controllers that support * only half-duplex, the wait state detection needs to be implemented * in hardware. TPM devices would set this flag when hardware flow * control is expected from SPI controller. */ #define SPI_TPM_HW_FLOW BIT(29) /* TPM HW flow control */ /* * All bits defined above should be covered by SPI_MODE_KERNEL_MASK. * The SPI_MODE_KERNEL_MASK has the SPI_MODE_USER_MASK counterpart, * which is defined in 'include/uapi/linux/spi/spi.h'. * The bits defined here are from bit 31 downwards, while in * SPI_MODE_USER_MASK are from 0 upwards. * These bits must not overlap. A static assert check should make sure of that. * If adding extra bits, make sure to decrease the bit index below as well. */ #define SPI_MODE_KERNEL_MASK (~(BIT(29) - 1)) u32 mode; int irq; void *controller_state; void *controller_data; char modalias[SPI_NAME_SIZE]; const char *driver_override; struct gpio_desc *cs_gpiod[SPI_CS_CNT_MAX]; /* Chip select gpio desc */ struct spi_delay word_delay; /* Inter-word delay */ /* CS delays */ struct spi_delay cs_setup; struct spi_delay cs_hold; struct spi_delay cs_inactive; /* The statistics */ struct spi_statistics __percpu *pcpu_statistics; /* Bit mask of the chipselect(s) that the driver need to use from * the chipselect array.When the controller is capable to handle * multiple chip selects & memories are connected in parallel * then more than one bit need to be set in cs_index_mask. */ u32 cs_index_mask : SPI_CS_CNT_MAX; /* * Likely need more hooks for more protocol options affecting how * the controller talks to each chip, like: * - memory packing (12 bit samples into low bits, others zeroed) * - priority * - chipselect delays * - ... */ }; /* Make sure that SPI_MODE_KERNEL_MASK & SPI_MODE_USER_MASK don't overlap */ static_assert((SPI_MODE_KERNEL_MASK & SPI_MODE_USER_MASK) == 0, "SPI_MODE_USER_MASK & SPI_MODE_KERNEL_MASK must not overlap"); static inline struct spi_device *to_spi_device(const struct device *dev) { return dev ? container_of(dev, struct spi_device, dev) : NULL; } /* Most drivers won't need to care about device refcounting */ static inline struct spi_device *spi_dev_get(struct spi_device *spi) { return (spi && get_device(&spi->dev)) ? spi : NULL; } static inline void spi_dev_put(struct spi_device *spi) { if (spi) put_device(&spi->dev); } /* ctldata is for the bus_controller driver's runtime state */ static inline void *spi_get_ctldata(const struct spi_device *spi) { return spi->controller_state; } static inline void spi_set_ctldata(struct spi_device *spi, void *state) { spi->controller_state = state; } /* Device driver data */ static inline void spi_set_drvdata(struct spi_device *spi, void *data) { dev_set_drvdata(&spi->dev, data); } static inline void *spi_get_drvdata(const struct spi_device *spi) { return dev_get_drvdata(&spi->dev); } static inline u8 spi_get_chipselect(const struct spi_device *spi, u8 idx) { return spi->chip_select[idx]; } static inline void spi_set_chipselect(struct spi_device *spi, u8 idx, u8 chipselect) { spi->chip_select[idx] = chipselect; } static inline struct gpio_desc *spi_get_csgpiod(const struct spi_device *spi, u8 idx) { return spi->cs_gpiod[idx]; } static inline void spi_set_csgpiod(struct spi_device *spi, u8 idx, struct gpio_desc *csgpiod) { spi->cs_gpiod[idx] = csgpiod; } static inline bool spi_is_csgpiod(struct spi_device *spi) { u8 idx; for (idx = 0; idx < SPI_CS_CNT_MAX; idx++) { if (spi_get_csgpiod(spi, idx)) return true; } return false; } /** * struct spi_driver - Host side "protocol" driver * @id_table: List of SPI devices supported by this driver * @probe: Binds this driver to the SPI device. Drivers can verify * that the device is actually present, and may need to configure * characteristics (such as bits_per_word) which weren't needed for * the initial configuration done during system setup. * @remove: Unbinds this driver from the SPI device * @shutdown: Standard shutdown callback used during system state * transitions such as powerdown/halt and kexec * @driver: SPI device drivers should initialize the name and owner * field of this structure. * * This represents the kind of device driver that uses SPI messages to * interact with the hardware at the other end of a SPI link. It's called * a "protocol" driver because it works through messages rather than talking * directly to SPI hardware (which is what the underlying SPI controller * driver does to pass those messages). These protocols are defined in the * specification for the device(s) supported by the driver. * * As a rule, those device protocols represent the lowest level interface * supported by a driver, and it will support upper level interfaces too. * Examples of such upper levels include frameworks like MTD, networking, * MMC, RTC, filesystem character device nodes, and hardware monitoring. */ struct spi_driver { const struct spi_device_id *id_table; int (*probe)(struct spi_device *spi); void (*remove)(struct spi_device *spi); void (*shutdown)(struct spi_device *spi); struct device_driver driver; }; static inline struct spi_driver *to_spi_driver(struct device_driver *drv) { return drv ? container_of(drv, struct spi_driver, driver) : NULL; } extern int __spi_register_driver(struct module *owner, struct spi_driver *sdrv); /** * spi_unregister_driver - reverse effect of spi_register_driver * @sdrv: the driver to unregister * Context: can sleep */ static inline void spi_unregister_driver(struct spi_driver *sdrv) { if (sdrv) driver_unregister(&sdrv->driver); } extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 chip_select); /* Use a define to avoid include chaining to get THIS_MODULE */ #define spi_register_driver(driver) \ __spi_register_driver(THIS_MODULE, driver) /** * module_spi_driver() - Helper macro for registering a SPI driver * @__spi_driver: spi_driver struct * * Helper macro for SPI drivers which do not do anything special in module * init/exit. This eliminates a lot of boilerplate. Each module may only * use this macro once, and calling it replaces module_init() and module_exit() */ #define module_spi_driver(__spi_driver) \ module_driver(__spi_driver, spi_register_driver, \ spi_unregister_driver) /** * struct spi_controller - interface to SPI master or slave controller * @dev: device interface to this driver * @list: link with the global spi_controller list * @bus_num: board-specific (and often SOC-specific) identifier for a * given SPI controller. * @num_chipselect: chipselects are used to distinguish individual * SPI slaves, and are numbered from zero to num_chipselects. * each slave has a chipselect signal, but it's common that not * every chipselect is connected to a slave. * @dma_alignment: SPI controller constraint on DMA buffers alignment. * @mode_bits: flags understood by this controller driver * @buswidth_override_bits: flags to override for this controller driver * @bits_per_word_mask: A mask indicating which values of bits_per_word are * supported by the driver. Bit n indicates that a bits_per_word n+1 is * supported. If set, the SPI core will reject any transfer with an * unsupported bits_per_word. If not set, this value is simply ignored, * and it's up to the individual driver to perform any validation. * @min_speed_hz: Lowest supported transfer speed * @max_speed_hz: Highest supported transfer speed * @flags: other constraints relevant to this driver * @slave: indicates that this is an SPI slave controller * @target: indicates that this is an SPI target controller * @devm_allocated: whether the allocation of this struct is devres-managed * @max_transfer_size: function that returns the max transfer size for * a &spi_device; may be %NULL, so the default %SIZE_MAX will be used. * @max_message_size: function that returns the max message size for * a &spi_device; may be %NULL, so the default %SIZE_MAX will be used. * @io_mutex: mutex for physical bus access * @add_lock: mutex to avoid adding devices to the same chipselect * @bus_lock_spinlock: spinlock for SPI bus locking * @bus_lock_mutex: mutex for exclusion of multiple callers * @bus_lock_flag: indicates that the SPI bus is locked for exclusive use * @setup: updates the device mode and clocking records used by a * device's SPI controller; protocol code may call this. This * must fail if an unrecognized or unsupported mode is requested. * It's always safe to call this unless transfers are pending on * the device whose settings are being modified. * @set_cs_timing: optional hook for SPI devices to request SPI master * controller for configuring specific CS setup time, hold time and inactive * delay interms of clock counts * @transfer: adds a message to the controller's transfer queue. * @cleanup: frees controller-specific state * @can_dma: determine whether this controller supports DMA * @dma_map_dev: device which can be used for DMA mapping * @cur_rx_dma_dev: device which is currently used for RX DMA mapping * @cur_tx_dma_dev: device which is currently used for TX DMA mapping * @queued: whether this controller is providing an internal message queue * @kworker: pointer to thread struct for message pump * @pump_messages: work struct for scheduling work to the message pump * @queue_lock: spinlock to synchronise access to message queue * @queue: message queue * @cur_msg: the currently in-flight message * @cur_msg_completion: a completion for the current in-flight message * @cur_msg_incomplete: Flag used internally to opportunistically skip * the @cur_msg_completion. This flag is used to check if the driver has * already called spi_finalize_current_message(). * @cur_msg_need_completion: Flag used internally to opportunistically skip * the @cur_msg_completion. This flag is used to signal the context that * is running spi_finalize_current_message() that it needs to complete() * @cur_msg_mapped: message has been mapped for DMA * @fallback: fallback to PIO if DMA transfer return failure with * SPI_TRANS_FAIL_NO_START. * @last_cs_mode_high: was (mode & SPI_CS_HIGH) true on the last call to set_cs. * @last_cs: the last chip_select that is recorded by set_cs, -1 on non chip * selected * @last_cs_index_mask: bit mask the last chip selects that were used * @xfer_completion: used by core transfer_one_message() * @busy: message pump is busy * @running: message pump is running * @rt: whether this queue is set to run as a realtime task * @auto_runtime_pm: the core should ensure a runtime PM reference is held * while the hardware is prepared, using the parent * device for the spidev * @max_dma_len: Maximum length of a DMA transfer for the device. * @prepare_transfer_hardware: a message will soon arrive from the queue * so the subsystem requests the driver to prepare the transfer hardware * by issuing this call * @transfer_one_message: the subsystem calls the driver to transfer a single * message while queuing transfers that arrive in the meantime. When the * driver is finished with this message, it must call * spi_finalize_current_message() so the subsystem can issue the next * message * @unprepare_transfer_hardware: there are currently no more messages on the * queue so the subsystem notifies the driver that it may relax the * hardware by issuing this call * * @set_cs: set the logic level of the chip select line. May be called * from interrupt context. * @optimize_message: optimize the message for reuse * @unoptimize_message: release resources allocated by optimize_message * @prepare_message: set up the controller to transfer a single message, * for example doing DMA mapping. Called from threaded * context. * @transfer_one: transfer a single spi_transfer. * * - return 0 if the transfer is finished, * - return 1 if the transfer is still in progress. When * the driver is finished with this transfer it must * call spi_finalize_current_transfer() so the subsystem * can issue the next transfer. If the transfer fails, the * driver must set the flag SPI_TRANS_FAIL_IO to * spi_transfer->error first, before calling * spi_finalize_current_transfer(). * Note: transfer_one and transfer_one_message are mutually * exclusive; when both are set, the generic subsystem does * not call your transfer_one callback. * @handle_err: the subsystem calls the driver to handle an error that occurs * in the generic implementation of transfer_one_message(). * @mem_ops: optimized/dedicated operations for interactions with SPI memory. * This field is optional and should only be implemented if the * controller has native support for memory like operations. * @mem_caps: controller capabilities for the handling of memory operations. * @unprepare_message: undo any work done by prepare_message(). * @slave_abort: abort the ongoing transfer request on an SPI slave controller * @target_abort: abort the ongoing transfer request on an SPI target controller * @cs_gpiods: Array of GPIO descriptors to use as chip select lines; one per CS * number. Any individual value may be NULL for CS lines that * are not GPIOs (driven by the SPI controller itself). * @use_gpio_descriptors: Turns on the code in the SPI core to parse and grab * GPIO descriptors. This will fill in @cs_gpiods and SPI devices will have * the cs_gpiod assigned if a GPIO line is found for the chipselect. * @unused_native_cs: When cs_gpiods is used, spi_register_controller() will * fill in this field with the first unused native CS, to be used by SPI * controller drivers that need to drive a native CS when using GPIO CS. * @max_native_cs: When cs_gpiods is used, and this field is filled in, * spi_register_controller() will validate all native CS (including the * unused native CS) against this value. * @pcpu_statistics: statistics for the spi_controller * @dma_tx: DMA transmit channel * @dma_rx: DMA receive channel * @dummy_rx: dummy receive buffer for full-duplex devices * @dummy_tx: dummy transmit buffer for full-duplex devices * @fw_translate_cs: If the boot firmware uses different numbering scheme * what Linux expects, this optional hook can be used to translate * between the two. * @ptp_sts_supported: If the driver sets this to true, it must provide a * time snapshot in @spi_transfer->ptp_sts as close as possible to the * moment in time when @spi_transfer->ptp_sts_word_pre and * @spi_transfer->ptp_sts_word_post were transmitted. * If the driver does not set this, the SPI core takes the snapshot as * close to the driver hand-over as possible. * @irq_flags: Interrupt enable state during PTP system timestamping * @queue_empty: signal green light for opportunistically skipping the queue * for spi_sync transfers. * @must_async: disable all fast paths in the core * * Each SPI controller can communicate with one or more @spi_device * children. These make a small bus, sharing MOSI, MISO and SCK signals * but not chip select signals. Each device may be configured to use a * different clock rate, since those shared signals are ignored unless * the chip is selected. * * The driver for an SPI controller manages access to those devices through * a queue of spi_message transactions, copying data between CPU memory and * an SPI slave device. For each such message it queues, it calls the * message's completion function when the transaction completes. */ struct spi_controller { struct device dev; struct list_head list; /* * Other than negative (== assign one dynamically), bus_num is fully * board-specific. Usually that simplifies to being SoC-specific. * example: one SoC has three SPI controllers, numbered 0..2, * and one board's schematics might show it using SPI-2. Software * would normally use bus_num=2 for that controller. */ s16 bus_num; /* * Chipselects will be integral to many controllers; some others * might use board-specific GPIOs. */ u16 num_chipselect; /* Some SPI controllers pose alignment requirements on DMAable * buffers; let protocol drivers know about these requirements. */ u16 dma_alignment; /* spi_device.mode flags understood by this controller driver */ u32 mode_bits; /* spi_device.mode flags override flags for this controller */ u32 buswidth_override_bits; /* Bitmask of supported bits_per_word for transfers */ u32 bits_per_word_mask; #define SPI_BPW_MASK(bits) BIT((bits) - 1) #define SPI_BPW_RANGE_MASK(min, max) GENMASK((max) - 1, (min) - 1) /* Limits on transfer speed */ u32 min_speed_hz; u32 max_speed_hz; /* Other constraints relevant to this driver */ u16 flags; #define SPI_CONTROLLER_HALF_DUPLEX BIT(0) /* Can't do full duplex */ #define SPI_CONTROLLER_NO_RX BIT(1) /* Can't do buffer read */ #define SPI_CONTROLLER_NO_TX BIT(2) /* Can't do buffer write */ #define SPI_CONTROLLER_MUST_RX BIT(3) /* Requires rx */ #define SPI_CONTROLLER_MUST_TX BIT(4) /* Requires tx */ #define SPI_CONTROLLER_GPIO_SS BIT(5) /* GPIO CS must select slave */ #define SPI_CONTROLLER_SUSPENDED BIT(6) /* Currently suspended */ /* * The spi-controller has multi chip select capability and can * assert/de-assert more than one chip select at once. */ #define SPI_CONTROLLER_MULTI_CS BIT(7) /* Flag indicating if the allocation of this struct is devres-managed */ bool devm_allocated; union { /* Flag indicating this is an SPI slave controller */ bool slave; /* Flag indicating this is an SPI target controller */ bool target; }; /* * On some hardware transfer / message size may be constrained * the limit may depend on device transfer settings. */ size_t (*max_transfer_size)(struct spi_device *spi); size_t (*max_message_size)(struct spi_device *spi); /* I/O mutex */ struct mutex io_mutex; /* Used to avoid adding the same CS twice */ struct mutex add_lock; /* Lock and mutex for SPI bus locking */ spinlock_t bus_lock_spinlock; struct mutex bus_lock_mutex; /* Flag indicating that the SPI bus is locked for exclusive use */ bool bus_lock_flag; /* * Setup mode and clock, etc (SPI driver may call many times). * * IMPORTANT: this may be called when transfers to another * device are active. DO NOT UPDATE SHARED REGISTERS in ways * which could break those transfers. */ int (*setup)(struct spi_device *spi); /* * set_cs_timing() method is for SPI controllers that supports * configuring CS timing. * * This hook allows SPI client drivers to request SPI controllers * to configure specific CS timing through spi_set_cs_timing() after * spi_setup(). */ int (*set_cs_timing)(struct spi_device *spi); /* * Bidirectional bulk transfers * * + The transfer() method may not sleep; its main role is * just to add the message to the queue. * + For now there's no remove-from-queue operation, or * any other request management * + To a given spi_device, message queueing is pure FIFO * * + The controller's main job is to process its message queue, * selecting a chip (for masters), then transferring data * + If there are multiple spi_device children, the i/o queue * arbitration algorithm is unspecified (round robin, FIFO, * priority, reservations, preemption, etc) * * + Chipselect stays active during the entire message * (unless modified by spi_transfer.cs_change != 0). * + The message transfers use clock and SPI mode parameters * previously established by setup() for this device */ int (*transfer)(struct spi_device *spi, struct spi_message *mesg); /* Called on release() to free memory provided by spi_controller */ void (*cleanup)(struct spi_device *spi); /* * Used to enable core support for DMA handling, if can_dma() * exists and returns true then the transfer will be mapped * prior to transfer_one() being called. The driver should * not modify or store xfer and dma_tx and dma_rx must be set * while the device is prepared. */ bool (*can_dma)(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *xfer); struct device *dma_map_dev; struct device *cur_rx_dma_dev; struct device *cur_tx_dma_dev; /* * These hooks are for drivers that want to use the generic * controller transfer queueing mechanism. If these are used, the * transfer() function above must NOT be specified by the driver. * Over time we expect SPI drivers to be phased over to this API. */ bool queued; struct kthread_worker *kworker; struct kthread_work pump_messages; spinlock_t queue_lock; struct list_head queue; struct spi_message *cur_msg; struct completion cur_msg_completion; bool cur_msg_incomplete; bool cur_msg_need_completion; bool busy; bool running; bool rt; bool auto_runtime_pm; bool cur_msg_mapped; bool fallback; bool last_cs_mode_high; s8 last_cs[SPI_CS_CNT_MAX]; u32 last_cs_index_mask : SPI_CS_CNT_MAX; struct completion xfer_completion; size_t max_dma_len; int (*optimize_message)(struct spi_message *msg); int (*unoptimize_message)(struct spi_message *msg); int (*prepare_transfer_hardware)(struct spi_controller *ctlr); int (*transfer_one_message)(struct spi_controller *ctlr, struct spi_message *mesg); int (*unprepare_transfer_hardware)(struct spi_controller *ctlr); int (*prepare_message)(struct spi_controller *ctlr, struct spi_message *message); int (*unprepare_message)(struct spi_controller *ctlr, struct spi_message *message); union { int (*slave_abort)(struct spi_controller *ctlr); int (*target_abort)(struct spi_controller *ctlr); }; /* * These hooks are for drivers that use a generic implementation * of transfer_one_message() provided by the core. */ void (*set_cs)(struct spi_device *spi, bool enable); int (*transfer_one)(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *transfer); void (*handle_err)(struct spi_controller *ctlr, struct spi_message *message); /* Optimized handlers for SPI memory-like operations. */ const struct spi_controller_mem_ops *mem_ops; const struct spi_controller_mem_caps *mem_caps; /* GPIO chip select */ struct gpio_desc **cs_gpiods; bool use_gpio_descriptors; s8 unused_native_cs; s8 max_native_cs; /* Statistics */ struct spi_statistics __percpu *pcpu_statistics; /* DMA channels for use with core dmaengine helpers */ struct dma_chan *dma_tx; struct dma_chan *dma_rx; /* Dummy data for full duplex devices */ void *dummy_rx; void *dummy_tx; int (*fw_translate_cs)(struct spi_controller *ctlr, unsigned cs); /* * Driver sets this field to indicate it is able to snapshot SPI * transfers (needed e.g. for reading the time of POSIX clocks) */ bool ptp_sts_supported; /* Interrupt enable state during PTP system timestamping */ unsigned long irq_flags; /* Flag for enabling opportunistic skipping of the queue in spi_sync */ bool queue_empty; bool must_async; }; static inline void *spi_controller_get_devdata(struct spi_controller *ctlr) { return dev_get_drvdata(&ctlr->dev); } static inline void spi_controller_set_devdata(struct spi_controller *ctlr, void *data) { dev_set_drvdata(&ctlr->dev, data); } static inline struct spi_controller *spi_controller_get(struct spi_controller *ctlr) { if (!ctlr || !get_device(&ctlr->dev)) return NULL; return ctlr; } static inline void spi_controller_put(struct spi_controller *ctlr) { if (ctlr) put_device(&ctlr->dev); } static inline bool spi_controller_is_slave(struct spi_controller *ctlr) { return IS_ENABLED(CONFIG_SPI_SLAVE) && ctlr->slave; } static inline bool spi_controller_is_target(struct spi_controller *ctlr) { return IS_ENABLED(CONFIG_SPI_SLAVE) && ctlr->target; } /* PM calls that need to be issued by the driver */ extern int spi_controller_suspend(struct spi_controller *ctlr); extern int spi_controller_resume(struct spi_controller *ctlr); /* Calls the driver make to interact with the message queue */ extern struct spi_message *spi_get_next_queued_message(struct spi_controller *ctlr); extern void spi_finalize_current_message(struct spi_controller *ctlr); extern void spi_finalize_current_transfer(struct spi_controller *ctlr); /* Helper calls for driver to timestamp transfer */ void spi_take_timestamp_pre(struct spi_controller *ctlr, struct spi_transfer *xfer, size_t progress, bool irqs_off); void spi_take_timestamp_post(struct spi_controller *ctlr, struct spi_transfer *xfer, size_t progress, bool irqs_off); /* The SPI driver core manages memory for the spi_controller classdev */ extern struct spi_controller *__spi_alloc_controller(struct device *host, unsigned int size, bool slave); static inline struct spi_controller *spi_alloc_master(struct device *host, unsigned int size) { return __spi_alloc_controller(host, size, false); } static inline struct spi_controller *spi_alloc_slave(struct device *host, unsigned int size) { if (!IS_ENABLED(CONFIG_SPI_SLAVE)) return NULL; return __spi_alloc_controller(host, size, true); } static inline struct spi_controller *spi_alloc_host(struct device *dev, unsigned int size) { return __spi_alloc_controller(dev, size, false); } static inline struct spi_controller *spi_alloc_target(struct device *dev, unsigned int size) { if (!IS_ENABLED(CONFIG_SPI_SLAVE)) return NULL; return __spi_alloc_controller(dev, size, true); } struct spi_controller *__devm_spi_alloc_controller(struct device *dev, unsigned int size, bool slave); static inline struct spi_controller *devm_spi_alloc_master(struct device *dev, unsigned int size) { return __devm_spi_alloc_controller(dev, size, false); } static inline struct spi_controller *devm_spi_alloc_slave(struct device *dev, unsigned int size) { if (!IS_ENABLED(CONFIG_SPI_SLAVE)) return NULL; return __devm_spi_alloc_controller(dev, size, true); } static inline struct spi_controller *devm_spi_alloc_host(struct device *dev, unsigned int size) { return __devm_spi_alloc_controller(dev, size, false); } static inline struct spi_controller *devm_spi_alloc_target(struct device *dev, unsigned int size) { if (!IS_ENABLED(CONFIG_SPI_SLAVE)) return NULL; return __devm_spi_alloc_controller(dev, size, true); } extern int spi_register_controller(struct spi_controller *ctlr); extern int devm_spi_register_controller(struct device *dev, struct spi_controller *ctlr); extern void spi_unregister_controller(struct spi_controller *ctlr); #if IS_ENABLED(CONFIG_ACPI) extern struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev); extern struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, struct acpi_device *adev, int index); int acpi_spi_count_resources(struct acpi_device *adev); #endif /* * SPI resource management while processing a SPI message */ typedef void (*spi_res_release_t)(struct spi_controller *ctlr, struct spi_message *msg, void *res); /** * struct spi_res - SPI resource management structure * @entry: list entry * @release: release code called prior to freeing this resource * @data: extra data allocated for the specific use-case * * This is based on ideas from devres, but focused on life-cycle * management during spi_message processing. */ struct spi_res { struct list_head entry; spi_res_release_t release; unsigned long long data[]; /* Guarantee ull alignment */ }; /*---------------------------------------------------------------------------*/ /* * I/O INTERFACE between SPI controller and protocol drivers * * Protocol drivers use a queue of spi_messages, each transferring data * between the controller and memory buffers. * * The spi_messages themselves consist of a series of read+write transfer * segments. Those segments always read the same number of bits as they * write; but one or the other is easily ignored by passing a NULL buffer * pointer. (This is unlike most types of I/O API, because SPI hardware * is full duplex.) * * NOTE: Allocation of spi_transfer and spi_message memory is entirely * up to the protocol driver, which guarantees the integrity of both (as * well as the data buffers) for as long as the message is queued. */ /** * struct spi_transfer - a read/write buffer pair * @tx_buf: data to be written (DMA-safe memory), or NULL * @rx_buf: data to be read (DMA-safe memory), or NULL * @tx_dma: DMA address of tx_buf, currently not for client use * @rx_dma: DMA address of rx_buf, currently not for client use * @tx_nbits: number of bits used for writing. If 0 the default * (SPI_NBITS_SINGLE) is used. * @rx_nbits: number of bits used for reading. If 0 the default * (SPI_NBITS_SINGLE) is used. * @len: size of rx and tx buffers (in bytes) * @speed_hz: Select a speed other than the device default for this * transfer. If 0 the default (from @spi_device) is used. * @bits_per_word: select a bits_per_word other than the device default * for this transfer. If 0 the default (from @spi_device) is used. * @dummy_data: indicates transfer is dummy bytes transfer. * @cs_off: performs the transfer with chipselect off. * @cs_change: affects chipselect after this transfer completes * @cs_change_delay: delay between cs deassert and assert when * @cs_change is set and @spi_transfer is not the last in @spi_message * @delay: delay to be introduced after this transfer before * (optionally) changing the chipselect status, then starting * the next transfer or completing this @spi_message. * @word_delay: inter word delay to be introduced after each word size * (set by bits_per_word) transmission. * @effective_speed_hz: the effective SCK-speed that was used to * transfer this transfer. Set to 0 if the SPI bus driver does * not support it. * @transfer_list: transfers are sequenced through @spi_message.transfers * @tx_sg: Scatterlist for transmit, currently not for client use * @rx_sg: Scatterlist for receive, currently not for client use * @ptp_sts_word_pre: The word (subject to bits_per_word semantics) offset * within @tx_buf for which the SPI device is requesting that the time * snapshot for this transfer begins. Upon completing the SPI transfer, * this value may have changed compared to what was requested, depending * on the available snapshotting resolution (DMA transfer, * @ptp_sts_supported is false, etc). * @ptp_sts_word_post: See @ptp_sts_word_post. The two can be equal (meaning * that a single byte should be snapshotted). * If the core takes care of the timestamp (if @ptp_sts_supported is false * for this controller), it will set @ptp_sts_word_pre to 0, and * @ptp_sts_word_post to the length of the transfer. This is done * purposefully (instead of setting to spi_transfer->len - 1) to denote * that a transfer-level snapshot taken from within the driver may still * be of higher quality. * @ptp_sts: Pointer to a memory location held by the SPI slave device where a * PTP system timestamp structure may lie. If drivers use PIO or their * hardware has some sort of assist for retrieving exact transfer timing, * they can (and should) assert @ptp_sts_supported and populate this * structure using the ptp_read_system_*ts helper functions. * The timestamp must represent the time at which the SPI slave device has * processed the word, i.e. the "pre" timestamp should be taken before * transmitting the "pre" word, and the "post" timestamp after receiving * transmit confirmation from the controller for the "post" word. * @timestamped: true if the transfer has been timestamped * @error: Error status logged by SPI controller driver. * * SPI transfers always write the same number of bytes as they read. * Protocol drivers should always provide @rx_buf and/or @tx_buf. * In some cases, they may also want to provide DMA addresses for * the data being transferred; that may reduce overhead, when the * underlying driver uses DMA. * * If the transmit buffer is NULL, zeroes will be shifted out * while filling @rx_buf. If the receive buffer is NULL, the data * shifted in will be discarded. Only "len" bytes shift out (or in). * It's an error to try to shift out a partial word. (For example, by * shifting out three bytes with word size of sixteen or twenty bits; * the former uses two bytes per word, the latter uses four bytes.) * * In-memory data values are always in native CPU byte order, translated * from the wire byte order (big-endian except with SPI_LSB_FIRST). So * for example when bits_per_word is sixteen, buffers are 2N bytes long * (@len = 2N) and hold N sixteen bit words in CPU byte order. * * When the word size of the SPI transfer is not a power-of-two multiple * of eight bits, those in-memory words include extra bits. In-memory * words are always seen by protocol drivers as right-justified, so the * undefined (rx) or unused (tx) bits are always the most significant bits. * * All SPI transfers start with the relevant chipselect active. Normally * it stays selected until after the last transfer in a message. Drivers * can affect the chipselect signal using cs_change. * * (i) If the transfer isn't the last one in the message, this flag is * used to make the chipselect briefly go inactive in the middle of the * message. Toggling chipselect in this way may be needed to terminate * a chip command, letting a single spi_message perform all of group of * chip transactions together. * * (ii) When the transfer is the last one in the message, the chip may * stay selected until the next transfer. On multi-device SPI busses * with nothing blocking messages going to other devices, this is just * a performance hint; starting a message to another device deselects * this one. But in other cases, this can be used to ensure correctness. * Some devices need protocol transactions to be built from a series of * spi_message submissions, where the content of one message is determined * by the results of previous messages and where the whole transaction * ends when the chipselect goes inactive. * * When SPI can transfer in 1x,2x or 4x. It can get this transfer information * from device through @tx_nbits and @rx_nbits. In Bi-direction, these * two should both be set. User can set transfer mode with SPI_NBITS_SINGLE(1x) * SPI_NBITS_DUAL(2x) and SPI_NBITS_QUAD(4x) to support these t