1/* 2 module/drivers.c 3 functions for manipulating drivers 4 5 COMEDI - Linux Control and Measurement Device Interface 6 Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org> 7 Copyright (C) 2002 Frank Mori Hess <fmhess@users.sourceforge.net> 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18*/ 19 20#include <linux/device.h> 21#include <linux/module.h> 22#include <linux/errno.h> 23#include <linux/kconfig.h> 24#include <linux/kernel.h> 25#include <linux/sched.h> 26#include <linux/fcntl.h> 27#include <linux/ioport.h> 28#include <linux/mm.h> 29#include <linux/slab.h> 30#include <linux/highmem.h> /* for SuSE brokenness */ 31#include <linux/vmalloc.h> 32#include <linux/cdev.h> 33#include <linux/dma-mapping.h> 34#include <linux/io.h> 35#include <linux/interrupt.h> 36#include <linux/firmware.h> 37 38#include "comedidev.h" 39#include "comedi_internal.h" 40 41struct comedi_driver *comedi_drivers; 42/* protects access to comedi_drivers */ 43DEFINE_MUTEX(comedi_drivers_list_lock); 44 45int comedi_set_hw_dev(struct comedi_device *dev, struct device *hw_dev) 46{ 47 if (hw_dev == dev->hw_dev) 48 return 0; 49 if (dev->hw_dev) 50 return -EEXIST; 51 dev->hw_dev = get_device(hw_dev); 52 return 0; 53} 54EXPORT_SYMBOL_GPL(comedi_set_hw_dev); 55 56static void comedi_clear_hw_dev(struct comedi_device *dev) 57{ 58 put_device(dev->hw_dev); 59 dev->hw_dev = NULL; 60} 61 62/** 63 * comedi_alloc_devpriv() - Allocate memory for the device private data. 64 * @dev: comedi_device struct 65 * @size: size of the memory to allocate 66 */ 67void *comedi_alloc_devpriv(struct comedi_device *dev, size_t size) 68{ 69 dev->private = kzalloc(size, GFP_KERNEL); 70 return dev->private; 71} 72EXPORT_SYMBOL_GPL(comedi_alloc_devpriv); 73 74int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices) 75{ 76 struct comedi_subdevice *s; 77 int i; 78 79 if (num_subdevices < 1) 80 return -EINVAL; 81 82 s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL); 83 if (!s) 84 return -ENOMEM; 85 dev->subdevices = s; 86 dev->n_subdevices = num_subdevices; 87 88 for (i = 0; i < num_subdevices; ++i) { 89 s = &dev->subdevices[i]; 90 s->device = dev; 91 s->index = i; 92 s->async_dma_dir = DMA_NONE; 93 spin_lock_init(&s->spin_lock); 94 s->minor = -1; 95 } 96 return 0; 97} 98EXPORT_SYMBOL_GPL(comedi_alloc_subdevices); 99 100/** 101 * comedi_alloc_subdev_readback() - Allocate memory for the subdevice readback. 102 * @s: comedi_subdevice struct 103 */ 104int comedi_alloc_subdev_readback(struct comedi_subdevice *s) 105{ 106 if (!s->n_chan) 107 return -EINVAL; 108 109 s->readback = kcalloc(s->n_chan, sizeof(*s->readback), GFP_KERNEL); 110 if (!s->readback) 111 return -ENOMEM; 112 113 if (!s->insn_read) 114 s->insn_read = comedi_readback_insn_read; 115 116 return 0; 117} 118EXPORT_SYMBOL_GPL(comedi_alloc_subdev_readback); 119 120static void comedi_device_detach_cleanup(struct comedi_device *dev) 121{ 122 int i; 123 struct comedi_subdevice *s; 124 125 if (dev->subdevices) { 126 for (i = 0; i < dev->n_subdevices; i++) { 127 s = &dev->subdevices[i]; 128 if (s->runflags & COMEDI_SRF_FREE_SPRIV) 129 kfree(s->private); 130 comedi_free_subdevice_minor(s); 131 if (s->async) { 132 comedi_buf_alloc(dev, s, 0); 133 kfree(s->async); 134 } 135 kfree(s->readback); 136 } 137 kfree(dev->subdevices); 138 dev->subdevices = NULL; 139 dev->n_subdevices = 0; 140 } 141 kfree(dev->private); 142 kfree(dev->pacer); 143 dev->private = NULL; 144 dev->pacer = NULL; 145 dev->driver = NULL; 146 dev->board_name = NULL; 147 dev->board_ptr = NULL; 148 dev->mmio = NULL; 149 dev->iobase = 0; 150 dev->iolen = 0; 151 dev->ioenabled = false; 152 dev->irq = 0; 153 dev->read_subdev = NULL; 154 dev->write_subdev = NULL; 155 dev->open = NULL; 156 dev->close = NULL; 157 comedi_clear_hw_dev(dev); 158} 159 160void comedi_device_detach(struct comedi_device *dev) 161{ 162 comedi_device_cancel_all(dev); 163 down_write(&dev->attach_lock); 164 dev->attached = false; 165 dev->detach_count++; 166 if (dev->driver) 167 dev->driver->detach(dev); 168 comedi_device_detach_cleanup(dev); 169 up_write(&dev->attach_lock); 170} 171 172static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 173{ 174 return -EINVAL; 175} 176 177int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 178 struct comedi_insn *insn, unsigned int *data) 179{ 180 return -EINVAL; 181} 182 183/** 184 * comedi_readback_insn_read() - A generic (*insn_read) for subdevice readback. 185 * @dev: comedi_device struct 186 * @s: comedi_subdevice struct 187 * @insn: comedi_insn struct 188 * @data: pointer to return the readback data 189 */ 190int comedi_readback_insn_read(struct comedi_device *dev, 191 struct comedi_subdevice *s, 192 struct comedi_insn *insn, 193 unsigned int *data) 194{ 195 unsigned int chan = CR_CHAN(insn->chanspec); 196 int i; 197 198 if (!s->readback) 199 return -EINVAL; 200 201 for (i = 0; i < insn->n; i++) 202 data[i] = s->readback[chan]; 203 204 return insn->n; 205} 206EXPORT_SYMBOL_GPL(comedi_readback_insn_read); 207 208/** 209 * comedi_timeout() - busy-wait for a driver condition to occur. 210 * @dev: comedi_device struct 211 * @s: comedi_subdevice struct 212 * @insn: comedi_insn struct 213 * @cb: callback to check for the condition 214 * @context: private context from the driver 215 */ 216int comedi_timeout(struct comedi_device *dev, 217 struct comedi_subdevice *s, 218 struct comedi_insn *insn, 219 int (*cb)(struct comedi_device *dev, 220 struct comedi_subdevice *s, 221 struct comedi_insn *insn, 222 unsigned long context), 223 unsigned long context) 224{ 225 unsigned long timeout = jiffies + msecs_to_jiffies(COMEDI_TIMEOUT_MS); 226 int ret; 227 228 while (time_before(jiffies, timeout)) { 229 ret = cb(dev, s, insn, context); 230 if (ret != -EBUSY) 231 return ret; /* success (0) or non EBUSY errno */ 232 cpu_relax(); 233 } 234 return -ETIMEDOUT; 235} 236EXPORT_SYMBOL_GPL(comedi_timeout); 237 238/** 239 * comedi_dio_insn_config() - boilerplate (*insn_config) for DIO subdevices. 240 * @dev: comedi_device struct 241 * @s: comedi_subdevice struct 242 * @insn: comedi_insn struct 243 * @data: parameters for the @insn 244 * @mask: io_bits mask for grouped channels 245 */ 246int comedi_dio_insn_config(struct comedi_device *dev, 247 struct comedi_subdevice *s, 248 struct comedi_insn *insn, 249 unsigned int *data, 250 unsigned int mask) 251{ 252 unsigned int chan_mask = 1 << CR_CHAN(insn->chanspec); 253 254 if (!mask) 255 mask = chan_mask; 256 257 switch (data[0]) { 258 case INSN_CONFIG_DIO_INPUT: 259 s->io_bits &= ~mask; 260 break; 261 262 case INSN_CONFIG_DIO_OUTPUT: 263 s->io_bits |= mask; 264 break; 265 266 case INSN_CONFIG_DIO_QUERY: 267 data[1] = (s->io_bits & mask) ? COMEDI_OUTPUT : COMEDI_INPUT; 268 return insn->n; 269 270 default: 271 return -EINVAL; 272 } 273 274 return 0; 275} 276EXPORT_SYMBOL_GPL(comedi_dio_insn_config); 277 278/** 279 * comedi_dio_update_state() - update the internal state of DIO subdevices. 280 * @s: comedi_subdevice struct 281 * @data: the channel mask and bits to update 282 */ 283unsigned int comedi_dio_update_state(struct comedi_subdevice *s, 284 unsigned int *data) 285{ 286 unsigned int chanmask = (s->n_chan < 32) ? ((1 << s->n_chan) - 1) 287 : 0xffffffff; 288 unsigned int mask = data[0] & chanmask; 289 unsigned int bits = data[1]; 290 291 if (mask) { 292 s->state &= ~mask; 293 s->state |= (bits & mask); 294 } 295 296 return mask; 297} 298EXPORT_SYMBOL_GPL(comedi_dio_update_state); 299 300/** 301 * comedi_bytes_per_scan - get length of asynchronous command "scan" in bytes 302 * @s: comedi_subdevice struct 303 * 304 * Determines the overall scan length according to the subdevice type and the 305 * number of channels in the scan. 306 * 307 * For digital input, output or input/output subdevices, samples for multiple 308 * channels are assumed to be packed into one or more unsigned short or 309 * unsigned int values according to the subdevice's SDF_LSAMPL flag. For other 310 * types of subdevice, samples are assumed to occupy a whole unsigned short or 311 * unsigned int according to the SDF_LSAMPL flag. 312 * 313 * Returns the overall scan length in bytes. 314 */ 315unsigned int comedi_bytes_per_scan(struct comedi_subdevice *s) 316{ 317 struct comedi_cmd *cmd = &s->async->cmd; 318 unsigned int num_samples; 319 unsigned int bits_per_sample; 320 321 switch (s->type) { 322 case COMEDI_SUBD_DI: 323 case COMEDI_SUBD_DO: 324 case COMEDI_SUBD_DIO: 325 bits_per_sample = 8 * comedi_bytes_per_sample(s); 326 num_samples = DIV_ROUND_UP(cmd->scan_end_arg, bits_per_sample); 327 break; 328 default: 329 num_samples = cmd->scan_end_arg; 330 break; 331 } 332 return comedi_samples_to_bytes(s, num_samples); 333} 334EXPORT_SYMBOL_GPL(comedi_bytes_per_scan); 335 336/** 337 * comedi_nscans_left - return the number of scans left in the command 338 * @s: comedi_subdevice struct 339 * @nscans: the expected number of scans 340 * 341 * If nscans is 0, the number of scans available in the async buffer will be 342 * used. Otherwise the expected number of scans will be used. 343 * 344 * If the async command has a stop_src of TRIG_COUNT, the nscans will be 345 * checked against the number of scans left in the command. 346 * 347 * The return value will then be either the expected number of scans or the 348 * number of scans remaining in the command. 349 */ 350unsigned int comedi_nscans_left(struct comedi_subdevice *s, 351 unsigned int nscans) 352{ 353 struct comedi_async *async = s->async; 354 struct comedi_cmd *cmd = &async->cmd; 355 356 if (nscans == 0) { 357 unsigned int nbytes = comedi_buf_read_n_available(s); 358 359 nscans = nbytes / comedi_bytes_per_scan(s); 360 } 361 362 if (cmd->stop_src == TRIG_COUNT) { 363 unsigned int scans_left = 0; 364 365 if (async->scans_done < cmd->stop_arg) 366 scans_left = cmd->stop_arg - async->scans_done; 367 368 if (nscans > scans_left) 369 nscans = scans_left; 370 } 371 return nscans; 372} 373EXPORT_SYMBOL_GPL(comedi_nscans_left); 374 375/** 376 * comedi_nsamples_left - return the number of samples left in the command 377 * @s: comedi_subdevice struct 378 * @nsamples: the expected number of samples 379 * 380 * Returns the expected number of samples of the number of samples remaining 381 * in the command. 382 */ 383unsigned int comedi_nsamples_left(struct comedi_subdevice *s, 384 unsigned int nsamples) 385{ 386 struct comedi_async *async = s->async; 387 struct comedi_cmd *cmd = &async->cmd; 388 389 if (cmd->stop_src == TRIG_COUNT) { 390 /* +1 to force comedi_nscans_left() to return the scans left */ 391 unsigned int nscans = (nsamples / cmd->scan_end_arg) + 1; 392 unsigned int scans_left = comedi_nscans_left(s, nscans); 393 unsigned int scan_pos = 394 comedi_bytes_to_samples(s, async->scan_progress); 395 unsigned long long samples_left = 0; 396 397 if (scans_left) { 398 samples_left = ((unsigned long long)scans_left * 399 cmd->scan_end_arg) - scan_pos; 400 } 401 402 if (samples_left < nsamples) 403 nsamples = samples_left; 404 } 405 return nsamples; 406} 407EXPORT_SYMBOL_GPL(comedi_nsamples_left); 408 409/** 410 * comedi_inc_scan_progress - update scan progress in asynchronous command 411 * @s: comedi_subdevice struct 412 * @num_bytes: amount of data in bytes to increment scan progress 413 * 414 * Increments the scan progress by the number of bytes specified by num_bytes. 415 * If the scan progress reaches or exceeds the scan length in bytes, reduce 416 * it modulo the scan length in bytes and set the "end of scan" asynchronous 417 * event flag to be processed later. 418 */ 419void comedi_inc_scan_progress(struct comedi_subdevice *s, 420 unsigned int num_bytes) 421{ 422 struct comedi_async *async = s->async; 423 struct comedi_cmd *cmd = &async->cmd; 424 unsigned int scan_length = comedi_bytes_per_scan(s); 425 426 /* track the 'cur_chan' for non-SDF_PACKED subdevices */ 427 if (!(s->subdev_flags & SDF_PACKED)) { 428 async->cur_chan += comedi_bytes_to_samples(s, num_bytes); 429 async->cur_chan %= cmd->chanlist_len; 430 } 431 432 async->scan_progress += num_bytes; 433 if (async->scan_progress >= scan_length) { 434 unsigned int nscans = async->scan_progress / scan_length; 435 436 if (async->scans_done < (UINT_MAX - nscans)) 437 async->scans_done += nscans; 438 else 439 async->scans_done = UINT_MAX; 440 441 async->scan_progress %= scan_length; 442 async->events |= COMEDI_CB_EOS; 443 } 444} 445EXPORT_SYMBOL_GPL(comedi_inc_scan_progress); 446 447/** 448 * comedi_handle_events - handle events and possibly stop acquisition 449 * @dev: comedi_device struct 450 * @s: comedi_subdevice struct 451 * 452 * Handles outstanding asynchronous acquisition event flags associated 453 * with the subdevice. Call the subdevice's "->cancel()" handler if the 454 * "end of acquisition", "error" or "overflow" event flags are set in order 455 * to stop the acquisition at the driver level. 456 * 457 * Calls comedi_event() to further process the event flags, which may mark 458 * the asynchronous command as no longer running, possibly terminated with 459 * an error, and may wake up tasks. 460 * 461 * Return a bit-mask of the handled events. 462 */ 463unsigned int comedi_handle_events(struct comedi_device *dev, 464 struct comedi_subdevice *s) 465{ 466 unsigned int events = s->async->events; 467 468 if (events == 0) 469 return events; 470 471 if (events & COMEDI_CB_CANCEL_MASK) 472 s->cancel(dev, s); 473 474 comedi_event(dev, s); 475 476 return events; 477} 478EXPORT_SYMBOL_GPL(comedi_handle_events); 479 480static int insn_rw_emulate_bits(struct comedi_device *dev, 481 struct comedi_subdevice *s, 482 struct comedi_insn *insn, unsigned int *data) 483{ 484 struct comedi_insn new_insn; 485 int ret; 486 static const unsigned channels_per_bitfield = 32; 487 488 unsigned chan = CR_CHAN(insn->chanspec); 489 const unsigned base_bitfield_channel = 490 (chan < channels_per_bitfield) ? 0 : chan; 491 unsigned int new_data[2]; 492 493 memset(new_data, 0, sizeof(new_data)); 494 memset(&new_insn, 0, sizeof(new_insn)); 495 new_insn.insn = INSN_BITS; 496 new_insn.chanspec = base_bitfield_channel; 497 new_insn.n = 2; 498 new_insn.subdev = insn->subdev; 499 500 if (insn->insn == INSN_WRITE) { 501 if (!(s->subdev_flags & SDF_WRITABLE)) 502 return -EINVAL; 503 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 504 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 505 : 0; /* bits */ 506 } 507 508 ret = s->insn_bits(dev, s, &new_insn, new_data); 509 if (ret < 0) 510 return ret; 511 512 if (insn->insn == INSN_READ) 513 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 514 515 return 1; 516} 517 518static int __comedi_device_postconfig_async(struct comedi_device *dev, 519 struct comedi_subdevice *s) 520{ 521 struct comedi_async *async; 522 unsigned int buf_size; 523 int ret; 524 525 if ((s->subdev_flags & (SDF_CMD_READ | SDF_CMD_WRITE)) == 0) { 526 dev_warn(dev->class_dev, 527 "async subdevices must support SDF_CMD_READ or SDF_CMD_WRITE\n"); 528 return -EINVAL; 529 } 530 if (!s->do_cmdtest) { 531 dev_warn(dev->class_dev, 532 "async subdevices must have a do_cmdtest() function\n"); 533 return -EINVAL; 534 } 535 536 async = kzalloc(sizeof(*async), GFP_KERNEL); 537 if (!async) 538 return -ENOMEM; 539 540 init_waitqueue_head(&async->wait_head); 541 s->async = async; 542 543 async->max_bufsize = comedi_default_buf_maxsize_kb * 1024; 544 buf_size = comedi_default_buf_size_kb * 1024; 545 if (buf_size > async->max_bufsize) 546 buf_size = async->max_bufsize; 547 548 if (comedi_buf_alloc(dev, s, buf_size) < 0) { 549 dev_warn(dev->class_dev, "Buffer allocation failed\n"); 550 return -ENOMEM; 551 } 552 if (s->buf_change) { 553 ret = s->buf_change(dev, s); 554 if (ret < 0) 555 return ret; 556 } 557 558 comedi_alloc_subdevice_minor(s); 559 560 return 0; 561} 562 563static int __comedi_device_postconfig(struct comedi_device *dev) 564{ 565 struct comedi_subdevice *s; 566 int ret; 567 int i; 568 569 for (i = 0; i < dev->n_subdevices; i++) { 570 s = &dev->subdevices[i]; 571 572 if (s->type == COMEDI_SUBD_UNUSED) 573 continue; 574 575 if (s->type == COMEDI_SUBD_DO) { 576 if (s->n_chan < 32) 577 s->io_bits = (1 << s->n_chan) - 1; 578 else 579 s->io_bits = 0xffffffff; 580 } 581 582 if (s->len_chanlist == 0) 583 s->len_chanlist = 1; 584 585 if (s->do_cmd) { 586 ret = __comedi_device_postconfig_async(dev, s); 587 if (ret) 588 return ret; 589 } 590 591 if (!s->range_table && !s->range_table_list) 592 s->range_table = &range_unknown; 593 594 if (!s->insn_read && s->insn_bits) 595 s->insn_read = insn_rw_emulate_bits; 596 if (!s->insn_write && s->insn_bits) 597 s->insn_write = insn_rw_emulate_bits; 598 599 if (!s->insn_read) 600 s->insn_read = insn_inval; 601 if (!s->insn_write) 602 s->insn_write = insn_inval; 603 if (!s->insn_bits) 604 s->insn_bits = insn_inval; 605 if (!s->insn_config) 606 s->insn_config = insn_inval; 607 608 if (!s->poll) 609 s->poll = poll_invalid; 610 } 611 612 return 0; 613} 614 615/* do a little post-config cleanup */ 616static int comedi_device_postconfig(struct comedi_device *dev) 617{ 618 int ret; 619 620 ret = __comedi_device_postconfig(dev); 621 if (ret < 0) 622 return ret; 623 down_write(&dev->attach_lock); 624 dev->attached = true; 625 up_write(&dev->attach_lock); 626 return 0; 627} 628 629/* 630 * Generic recognize function for drivers that register their supported 631 * board names. 632 * 633 * 'driv->board_name' points to a 'const char *' member within the 634 * zeroth element of an array of some private board information 635 * structure, say 'struct foo_board' containing a member 'const char 636 * *board_name' that is initialized to point to a board name string that 637 * is one of the candidates matched against this function's 'name' 638 * parameter. 639 * 640 * 'driv->offset' is the size of the private board information 641 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is 642 * the length of the array of private board information structures. 643 * 644 * If one of the board names in the array of private board information 645 * structures matches the name supplied to this function, the function 646 * returns a pointer to the pointer to the board name, otherwise it 647 * returns NULL. The return value ends up in the 'board_ptr' member of 648 * a 'struct comedi_device' that the low-level comedi driver's 649 * 'attach()' hook can convert to a point to a particular element of its 650 * array of private board information structures by subtracting the 651 * offset of the member that points to the board name. (No subtraction 652 * is required if the board name pointer is the first member of the 653 * private board information structure, which is generally the case.) 654 */ 655static void *comedi_recognize(struct comedi_driver *driv, const char *name) 656{ 657 char **name_ptr = (char **)driv->board_name; 658 int i; 659 660 for (i = 0; i < driv->num_names; i++) { 661 if (strcmp(*name_ptr, name) == 0) 662 return name_ptr; 663 name_ptr = (void *)name_ptr + driv->offset; 664 } 665 666 return NULL; 667} 668 669static void comedi_report_boards(struct comedi_driver *driv) 670{ 671 unsigned int i; 672 const char *const *name_ptr; 673 674 pr_info("comedi: valid board names for %s driver are:\n", 675 driv->driver_name); 676 677 name_ptr = driv->board_name; 678 for (i = 0; i < driv->num_names; i++) { 679 pr_info(" %s\n", *name_ptr); 680 name_ptr = (const char **)((char *)name_ptr + driv->offset); 681 } 682 683 if (driv->num_names == 0) 684 pr_info(" %s\n", driv->driver_name); 685} 686 687/** 688 * comedi_load_firmware() - Request and load firmware for a device. 689 * @dev: comedi_device struct 690 * @hw_device: device struct for the comedi_device 691 * @name: the name of the firmware image 692 * @cb: callback to the upload the firmware image 693 * @context: private context from the driver 694 */ 695int comedi_load_firmware(struct comedi_device *dev, 696 struct device *device, 697 const char *name, 698 int (*cb)(struct comedi_device *dev, 699 const u8 *data, size_t size, 700 unsigned long context), 701 unsigned long context) 702{ 703 const struct firmware *fw; 704 int ret; 705 706 if (!cb) 707 return -EINVAL; 708 709 ret = request_firmware(&fw, name, device); 710 if (ret == 0) { 711 ret = cb(dev, fw->data, fw->size, context); 712 release_firmware(fw); 713 } 714 715 return ret < 0 ? ret : 0; 716} 717EXPORT_SYMBOL_GPL(comedi_load_firmware); 718 719/** 720 * __comedi_request_region() - Request an I/O reqion for a legacy driver. 721 * @dev: comedi_device struct 722 * @start: base address of the I/O reqion 723 * @len: length of the I/O region 724 */ 725int __comedi_request_region(struct comedi_device *dev, 726 unsigned long start, unsigned long len) 727{ 728 if (!start) { 729 dev_warn(dev->class_dev, 730 "%s: a I/O base address must be specified\n", 731 dev->board_name); 732 return -EINVAL; 733 } 734 735 if (!request_region(start, len, dev->board_name)) { 736 dev_warn(dev->class_dev, "%s: I/O port conflict (%#lx,%lu)\n", 737 dev->board_name, start, len); 738 return -EIO; 739 } 740 741 return 0; 742} 743EXPORT_SYMBOL_GPL(__comedi_request_region); 744 745/** 746 * comedi_request_region() - Request an I/O reqion for a legacy driver. 747 * @dev: comedi_device struct 748 * @start: base address of the I/O reqion 749 * @len: length of the I/O region 750 */ 751int comedi_request_region(struct comedi_device *dev, 752 unsigned long start, unsigned long len) 753{ 754 int ret; 755 756 ret = __comedi_request_region(dev, start, len); 757 if (ret == 0) { 758 dev->iobase = start; 759 dev->iolen = len; 760 } 761 762 return ret; 763} 764EXPORT_SYMBOL_GPL(comedi_request_region); 765 766/** 767 * comedi_legacy_detach() - A generic (*detach) function for legacy drivers. 768 * @dev: comedi_device struct 769 */ 770void comedi_legacy_detach(struct comedi_device *dev) 771{ 772 if (dev->irq) { 773 free_irq(dev->irq, dev); 774 dev->irq = 0; 775 } 776 if (dev->iobase && dev->iolen) { 777 release_region(dev->iobase, dev->iolen); 778 dev->iobase = 0; 779 dev->iolen = 0; 780 } 781} 782EXPORT_SYMBOL_GPL(comedi_legacy_detach); 783 784int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 785{ 786 struct comedi_driver *driv; 787 int ret; 788 789 if (dev->attached) 790 return -EBUSY; 791 792 mutex_lock(&comedi_drivers_list_lock); 793 for (driv = comedi_drivers; driv; driv = driv->next) { 794 if (!try_module_get(driv->module)) 795 continue; 796 if (driv->num_names) { 797 dev->board_ptr = comedi_recognize(driv, it->board_name); 798 if (dev->board_ptr) 799 break; 800 } else if (strcmp(driv->driver_name, it->board_name) == 0) { 801 break; 802 } 803 module_put(driv->module); 804 } 805 if (!driv) { 806 /* recognize has failed if we get here */ 807 /* report valid board names before returning error */ 808 for (driv = comedi_drivers; driv; driv = driv->next) { 809 if (!try_module_get(driv->module)) 810 continue; 811 comedi_report_boards(driv); 812 module_put(driv->module); 813 } 814 ret = -EIO; 815 goto out; 816 } 817 if (!driv->attach) { 818 /* driver does not support manual configuration */ 819 dev_warn(dev->class_dev, 820 "driver '%s' does not support attach using comedi_config\n", 821 driv->driver_name); 822 module_put(driv->module); 823 ret = -ENOSYS; 824 goto out; 825 } 826 dev->driver = driv; 827 dev->board_name = dev->board_ptr ? *(const char **)dev->board_ptr 828 : dev->driver->driver_name; 829 ret = driv->attach(dev, it); 830 if (ret >= 0) 831 ret = comedi_device_postconfig(dev); 832 if (ret < 0) { 833 comedi_device_detach(dev); 834 module_put(driv->module); 835 } 836 /* On success, the driver module count has been incremented. */ 837out: 838 mutex_unlock(&comedi_drivers_list_lock); 839 return ret; 840} 841 842int comedi_auto_config(struct device *hardware_device, 843 struct comedi_driver *driver, unsigned long context) 844{ 845 struct comedi_device *dev; 846 int ret; 847 848 if (!hardware_device) { 849 pr_warn("BUG! comedi_auto_config called with NULL hardware_device\n"); 850 return -EINVAL; 851 } 852 if (!driver) { 853 dev_warn(hardware_device, 854 "BUG! comedi_auto_config called with NULL comedi driver\n"); 855 return -EINVAL; 856 } 857 858 if (!driver->auto_attach) { 859 dev_warn(hardware_device, 860 "BUG! comedi driver '%s' has no auto_attach handler\n", 861 driver->driver_name); 862 return -EINVAL; 863 } 864 865 dev = comedi_alloc_board_minor(hardware_device); 866 if (IS_ERR(dev)) { 867 dev_warn(hardware_device, 868 "driver '%s' could not create device.\n", 869 driver->driver_name); 870 return PTR_ERR(dev); 871 } 872 /* Note: comedi_alloc_board_minor() locked dev->mutex. */ 873 874 dev->driver = driver; 875 dev->board_name = dev->driver->driver_name; 876 ret = driver->auto_attach(dev, context); 877 if (ret >= 0) 878 ret = comedi_device_postconfig(dev); 879 mutex_unlock(&dev->mutex); 880 881 if (ret < 0) { 882 dev_warn(hardware_device, 883 "driver '%s' failed to auto-configure device.\n", 884 driver->driver_name); 885 comedi_release_hardware_device(hardware_device); 886 } else { 887 /* 888 * class_dev should be set properly here 889 * after a successful auto config 890 */ 891 dev_info(dev->class_dev, 892 "driver '%s' has successfully auto-configured '%s'.\n", 893 driver->driver_name, dev->board_name); 894 } 895 return ret; 896} 897EXPORT_SYMBOL_GPL(comedi_auto_config); 898 899void comedi_auto_unconfig(struct device *hardware_device) 900{ 901 if (!hardware_device) 902 return; 903 comedi_release_hardware_device(hardware_device); 904} 905EXPORT_SYMBOL_GPL(comedi_auto_unconfig); 906 907int comedi_driver_register(struct comedi_driver *driver) 908{ 909 mutex_lock(&comedi_drivers_list_lock); 910 driver->next = comedi_drivers; 911 comedi_drivers = driver; 912 mutex_unlock(&comedi_drivers_list_lock); 913 914 return 0; 915} 916EXPORT_SYMBOL_GPL(comedi_driver_register); 917 918void comedi_driver_unregister(struct comedi_driver *driver) 919{ 920 struct comedi_driver *prev; 921 int i; 922 923 /* unlink the driver */ 924 mutex_lock(&comedi_drivers_list_lock); 925 if (comedi_drivers == driver) { 926 comedi_drivers = driver->next; 927 } else { 928 for (prev = comedi_drivers; prev->next; prev = prev->next) { 929 if (prev->next == driver) { 930 prev->next = driver->next; 931 break; 932 } 933 } 934 } 935 mutex_unlock(&comedi_drivers_list_lock); 936 937 /* check for devices using this driver */ 938 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 939 struct comedi_device *dev = comedi_dev_get_from_minor(i); 940 941 if (!dev) 942 continue; 943 944 mutex_lock(&dev->mutex); 945 if (dev->attached && dev->driver == driver) { 946 if (dev->use_count) 947 dev_warn(dev->class_dev, 948 "BUG! detaching device with use_count=%d\n", 949 dev->use_count); 950 comedi_device_detach(dev); 951 } 952 mutex_unlock(&dev->mutex); 953 comedi_dev_put(dev); 954 } 955} 956EXPORT_SYMBOL_GPL(comedi_driver_unregister); 957