drivers.c revision a692e9743a7b2085afbca2f7e50a449c3e205cc0
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 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 21 22*/ 23 24#define _GNU_SOURCE 25 26#define __NO_VERSION__ 27#include <linux/device.h> 28#include <linux/module.h> 29#include <linux/pci.h> 30#include <linux/usb.h> 31#include <linux/errno.h> 32#include <linux/kconfig.h> 33#include <linux/kernel.h> 34#include <linux/sched.h> 35#include <linux/fcntl.h> 36#include <linux/delay.h> 37#include <linux/ioport.h> 38#include <linux/mm.h> 39#include <linux/slab.h> 40#include <linux/highmem.h> /* for SuSE brokenness */ 41#include <linux/vmalloc.h> 42#include <linux/cdev.h> 43#include <linux/dma-mapping.h> 44#include <linux/io.h> 45 46#include "comedidev.h" 47#include "comedi_internal.h" 48 49static int postconfig(struct comedi_device *dev); 50static int insn_rw_emulate_bits(struct comedi_device *dev, 51 struct comedi_subdevice *s, 52 struct comedi_insn *insn, unsigned int *data); 53static void *comedi_recognize(struct comedi_driver *driv, const char *name); 54static void comedi_report_boards(struct comedi_driver *driv); 55static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s); 56 57struct comedi_driver *comedi_drivers; 58 59int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices) 60{ 61 struct comedi_subdevice *s; 62 int i; 63 64 if (num_subdevices < 1) 65 return -EINVAL; 66 67 s = kcalloc(num_subdevices, sizeof(*s), GFP_KERNEL); 68 if (!s) 69 return -ENOMEM; 70 dev->subdevices = s; 71 dev->n_subdevices = num_subdevices; 72 73 for (i = 0; i < num_subdevices; ++i) { 74 s = &dev->subdevices[i]; 75 s->device = dev; 76 s->async_dma_dir = DMA_NONE; 77 spin_lock_init(&s->spin_lock); 78 s->minor = -1; 79 } 80 return 0; 81} 82EXPORT_SYMBOL_GPL(comedi_alloc_subdevices); 83 84static void cleanup_device(struct comedi_device *dev) 85{ 86 int i; 87 struct comedi_subdevice *s; 88 89 if (dev->subdevices) { 90 for (i = 0; i < dev->n_subdevices; i++) { 91 s = &dev->subdevices[i]; 92 comedi_free_subdevice_minor(s); 93 if (s->async) { 94 comedi_buf_alloc(dev, s, 0); 95 kfree(s->async); 96 } 97 } 98 kfree(dev->subdevices); 99 dev->subdevices = NULL; 100 dev->n_subdevices = 0; 101 } 102 kfree(dev->private); 103 dev->private = NULL; 104 dev->driver = NULL; 105 dev->board_name = NULL; 106 dev->board_ptr = NULL; 107 dev->iobase = 0; 108 dev->irq = 0; 109 dev->read_subdev = NULL; 110 dev->write_subdev = NULL; 111 dev->open = NULL; 112 dev->close = NULL; 113 comedi_set_hw_dev(dev, NULL); 114} 115 116static void __comedi_device_detach(struct comedi_device *dev) 117{ 118 dev->attached = 0; 119 if (dev->driver) 120 dev->driver->detach(dev); 121 else 122 dev_warn(dev->class_dev, 123 "BUG: dev->driver=NULL in comedi_device_detach()\n"); 124 cleanup_device(dev); 125} 126 127void comedi_device_detach(struct comedi_device *dev) 128{ 129 if (!dev->attached) 130 return; 131 __comedi_device_detach(dev); 132} 133 134/* do a little post-config cleanup */ 135/* called with module refcount incremented, decrements it */ 136static int comedi_device_postconfig(struct comedi_device *dev) 137{ 138 int ret = postconfig(dev); 139 module_put(dev->driver->module); 140 if (ret < 0) { 141 __comedi_device_detach(dev); 142 return ret; 143 } 144 if (!dev->board_name) { 145 dev_warn(dev->class_dev, "BUG: dev->board_name=NULL\n"); 146 dev->board_name = "BUG"; 147 } 148 smp_wmb(); 149 dev->attached = 1; 150 return 0; 151} 152 153int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 154{ 155 struct comedi_driver *driv; 156 int ret; 157 158 if (dev->attached) 159 return -EBUSY; 160 161 for (driv = comedi_drivers; driv; driv = driv->next) { 162 if (!try_module_get(driv->module)) 163 continue; 164 if (driv->num_names) { 165 dev->board_ptr = comedi_recognize(driv, it->board_name); 166 if (dev->board_ptr) 167 break; 168 } else if (strcmp(driv->driver_name, it->board_name) == 0) 169 break; 170 module_put(driv->module); 171 } 172 if (driv == NULL) { 173 /* recognize has failed if we get here */ 174 /* report valid board names before returning error */ 175 for (driv = comedi_drivers; driv; driv = driv->next) { 176 if (!try_module_get(driv->module)) 177 continue; 178 comedi_report_boards(driv); 179 module_put(driv->module); 180 } 181 return -EIO; 182 } 183 if (driv->attach == NULL) { 184 /* driver does not support manual configuration */ 185 dev_warn(dev->class_dev, 186 "driver '%s' does not support attach using comedi_config\n", 187 driv->driver_name); 188 module_put(driv->module); 189 return -ENOSYS; 190 } 191 /* initialize dev->driver here so 192 * comedi_error() can be called from attach */ 193 dev->driver = driv; 194 ret = driv->attach(dev, it); 195 if (ret < 0) { 196 module_put(dev->driver->module); 197 __comedi_device_detach(dev); 198 return ret; 199 } 200 return comedi_device_postconfig(dev); 201} 202 203int comedi_driver_register(struct comedi_driver *driver) 204{ 205 driver->next = comedi_drivers; 206 comedi_drivers = driver; 207 208 return 0; 209} 210EXPORT_SYMBOL(comedi_driver_register); 211 212int comedi_driver_unregister(struct comedi_driver *driver) 213{ 214 struct comedi_driver *prev; 215 int i; 216 217 /* check for devices using this driver */ 218 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 219 struct comedi_device_file_info *dev_file_info = 220 comedi_get_device_file_info(i); 221 struct comedi_device *dev; 222 223 if (dev_file_info == NULL) 224 continue; 225 dev = dev_file_info->device; 226 227 mutex_lock(&dev->mutex); 228 if (dev->attached && dev->driver == driver) { 229 if (dev->use_count) 230 dev_warn(dev->class_dev, 231 "BUG! detaching device with use_count=%d\n", 232 dev->use_count); 233 comedi_device_detach(dev); 234 } 235 mutex_unlock(&dev->mutex); 236 } 237 238 if (comedi_drivers == driver) { 239 comedi_drivers = driver->next; 240 return 0; 241 } 242 243 for (prev = comedi_drivers; prev->next; prev = prev->next) { 244 if (prev->next == driver) { 245 prev->next = driver->next; 246 return 0; 247 } 248 } 249 return -EINVAL; 250} 251EXPORT_SYMBOL(comedi_driver_unregister); 252 253static int postconfig(struct comedi_device *dev) 254{ 255 int i; 256 struct comedi_subdevice *s; 257 struct comedi_async *async = NULL; 258 int ret; 259 260 for (i = 0; i < dev->n_subdevices; i++) { 261 s = &dev->subdevices[i]; 262 263 if (s->type == COMEDI_SUBD_UNUSED) 264 continue; 265 266 if (s->len_chanlist == 0) 267 s->len_chanlist = 1; 268 269 if (s->do_cmd) { 270 unsigned int buf_size; 271 272 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 273 SDF_CMD_WRITE)) == 0); 274 BUG_ON(!s->do_cmdtest); 275 276 async = 277 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 278 if (async == NULL) { 279 dev_warn(dev->class_dev, 280 "failed to allocate async struct\n"); 281 return -ENOMEM; 282 } 283 init_waitqueue_head(&async->wait_head); 284 async->subdevice = s; 285 s->async = async; 286 287 async->max_bufsize = 288 comedi_default_buf_maxsize_kb * 1024; 289 buf_size = comedi_default_buf_size_kb * 1024; 290 if (buf_size > async->max_bufsize) 291 buf_size = async->max_bufsize; 292 293 async->prealloc_buf = NULL; 294 async->prealloc_bufsz = 0; 295 if (comedi_buf_alloc(dev, s, buf_size) < 0) { 296 dev_warn(dev->class_dev, 297 "Buffer allocation failed\n"); 298 return -ENOMEM; 299 } 300 if (s->buf_change) { 301 ret = s->buf_change(dev, s, buf_size); 302 if (ret < 0) 303 return ret; 304 } 305 comedi_alloc_subdevice_minor(dev, s); 306 } 307 308 if (!s->range_table && !s->range_table_list) 309 s->range_table = &range_unknown; 310 311 if (!s->insn_read && s->insn_bits) 312 s->insn_read = insn_rw_emulate_bits; 313 if (!s->insn_write && s->insn_bits) 314 s->insn_write = insn_rw_emulate_bits; 315 316 if (!s->insn_read) 317 s->insn_read = insn_inval; 318 if (!s->insn_write) 319 s->insn_write = insn_inval; 320 if (!s->insn_bits) 321 s->insn_bits = insn_inval; 322 if (!s->insn_config) 323 s->insn_config = insn_inval; 324 325 if (!s->poll) 326 s->poll = poll_invalid; 327 } 328 329 return 0; 330} 331 332/* 333 * Generic recognize function for drivers that register their supported 334 * board names. 335 * 336 * 'driv->board_name' points to a 'const char *' member within the 337 * zeroth element of an array of some private board information 338 * structure, say 'struct foo_board' containing a member 'const char 339 * *board_name' that is initialized to point to a board name string that 340 * is one of the candidates matched against this function's 'name' 341 * parameter. 342 * 343 * 'driv->offset' is the size of the private board information 344 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is 345 * the length of the array of private board information structures. 346 * 347 * If one of the board names in the array of private board information 348 * structures matches the name supplied to this function, the function 349 * returns a pointer to the pointer to the board name, otherwise it 350 * returns NULL. The return value ends up in the 'board_ptr' member of 351 * a 'struct comedi_device' that the low-level comedi driver's 352 * 'attach()' hook can convert to a point to a particular element of its 353 * array of private board information structures by subtracting the 354 * offset of the member that points to the board name. (No subtraction 355 * is required if the board name pointer is the first member of the 356 * private board information structure, which is generally the case.) 357 */ 358static void *comedi_recognize(struct comedi_driver *driv, const char *name) 359{ 360 char **name_ptr = (char **)driv->board_name; 361 int i; 362 363 for (i = 0; i < driv->num_names; i++) { 364 if (strcmp(*name_ptr, name) == 0) 365 return name_ptr; 366 name_ptr = (void *)name_ptr + driv->offset; 367 } 368 369 return NULL; 370} 371 372static void comedi_report_boards(struct comedi_driver *driv) 373{ 374 unsigned int i; 375 const char *const *name_ptr; 376 377 pr_info("comedi: valid board names for %s driver are:\n", 378 driv->driver_name); 379 380 name_ptr = driv->board_name; 381 for (i = 0; i < driv->num_names; i++) { 382 pr_info(" %s\n", *name_ptr); 383 name_ptr = (const char **)((char *)name_ptr + driv->offset); 384 } 385 386 if (driv->num_names == 0) 387 pr_info(" %s\n", driv->driver_name); 388} 389 390static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 391{ 392 return -EINVAL; 393} 394 395int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 396 struct comedi_insn *insn, unsigned int *data) 397{ 398 return -EINVAL; 399} 400 401static int insn_rw_emulate_bits(struct comedi_device *dev, 402 struct comedi_subdevice *s, 403 struct comedi_insn *insn, unsigned int *data) 404{ 405 struct comedi_insn new_insn; 406 int ret; 407 static const unsigned channels_per_bitfield = 32; 408 409 unsigned chan = CR_CHAN(insn->chanspec); 410 const unsigned base_bitfield_channel = 411 (chan < channels_per_bitfield) ? 0 : chan; 412 unsigned int new_data[2]; 413 memset(new_data, 0, sizeof(new_data)); 414 memset(&new_insn, 0, sizeof(new_insn)); 415 new_insn.insn = INSN_BITS; 416 new_insn.chanspec = base_bitfield_channel; 417 new_insn.n = 2; 418 new_insn.subdev = insn->subdev; 419 420 if (insn->insn == INSN_WRITE) { 421 if (!(s->subdev_flags & SDF_WRITABLE)) 422 return -EINVAL; 423 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 424 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 425 : 0; /* bits */ 426 } 427 428 ret = s->insn_bits(dev, s, &new_insn, new_data); 429 if (ret < 0) 430 return ret; 431 432 if (insn->insn == INSN_READ) 433 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 434 435 return 1; 436} 437 438int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 439 unsigned long new_size) 440{ 441 struct comedi_async *async = s->async; 442 443 /* Round up new_size to multiple of PAGE_SIZE */ 444 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 445 446 /* if no change is required, do nothing */ 447 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 448 return 0; 449 450 /* deallocate old buffer */ 451 if (async->prealloc_buf) { 452 vunmap(async->prealloc_buf); 453 async->prealloc_buf = NULL; 454 async->prealloc_bufsz = 0; 455 } 456 if (async->buf_page_list) { 457 unsigned i; 458 for (i = 0; i < async->n_buf_pages; ++i) { 459 if (async->buf_page_list[i].virt_addr) { 460 clear_bit(PG_reserved, 461 &(virt_to_page(async->buf_page_list[i]. 462 virt_addr)->flags)); 463 if (s->async_dma_dir != DMA_NONE) { 464 dma_free_coherent(dev->hw_dev, 465 PAGE_SIZE, 466 async-> 467 buf_page_list 468 [i].virt_addr, 469 async-> 470 buf_page_list 471 [i].dma_addr); 472 } else { 473 free_page((unsigned long) 474 async->buf_page_list[i]. 475 virt_addr); 476 } 477 } 478 } 479 vfree(async->buf_page_list); 480 async->buf_page_list = NULL; 481 async->n_buf_pages = 0; 482 } 483 /* allocate new buffer */ 484 if (new_size) { 485 unsigned i = 0; 486 unsigned n_pages = new_size >> PAGE_SHIFT; 487 struct page **pages = NULL; 488 489 async->buf_page_list = 490 vzalloc(sizeof(struct comedi_buf_page) * n_pages); 491 if (async->buf_page_list) 492 pages = vmalloc(sizeof(struct page *) * n_pages); 493 494 if (pages) { 495 for (i = 0; i < n_pages; i++) { 496 if (s->async_dma_dir != DMA_NONE) { 497 async->buf_page_list[i].virt_addr = 498 dma_alloc_coherent(dev->hw_dev, 499 PAGE_SIZE, 500 &async-> 501 buf_page_list 502 [i].dma_addr, 503 GFP_KERNEL | 504 __GFP_COMP); 505 } else { 506 async->buf_page_list[i].virt_addr = 507 (void *) 508 get_zeroed_page(GFP_KERNEL); 509 } 510 if (async->buf_page_list[i].virt_addr == NULL) 511 break; 512 513 set_bit(PG_reserved, 514 &(virt_to_page(async->buf_page_list[i]. 515 virt_addr)->flags)); 516 pages[i] = virt_to_page(async->buf_page_list[i]. 517 virt_addr); 518 } 519 } 520 if (i == n_pages) { 521 async->prealloc_buf = 522#ifdef PAGE_KERNEL_NOCACHE 523 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 524#else 525 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL); 526#endif 527 } 528 vfree(pages); 529 530 if (async->prealloc_buf == NULL) { 531 /* Some allocation failed above. */ 532 if (async->buf_page_list) { 533 for (i = 0; i < n_pages; i++) { 534 if (async->buf_page_list[i].virt_addr == 535 NULL) { 536 break; 537 } 538 clear_bit(PG_reserved, 539 &(virt_to_page(async-> 540 buf_page_list[i]. 541 virt_addr)->flags)); 542 if (s->async_dma_dir != DMA_NONE) { 543 dma_free_coherent(dev->hw_dev, 544 PAGE_SIZE, 545 async-> 546 buf_page_list 547 [i].virt_addr, 548 async-> 549 buf_page_list 550 [i].dma_addr); 551 } else { 552 free_page((unsigned long) 553 async->buf_page_list 554 [i].virt_addr); 555 } 556 } 557 vfree(async->buf_page_list); 558 async->buf_page_list = NULL; 559 } 560 return -ENOMEM; 561 } 562 async->n_buf_pages = n_pages; 563 } 564 async->prealloc_bufsz = new_size; 565 566 return 0; 567} 568 569/* munging is applied to data by core as it passes between user 570 * and kernel space */ 571static unsigned int comedi_buf_munge(struct comedi_async *async, 572 unsigned int num_bytes) 573{ 574 struct comedi_subdevice *s = async->subdevice; 575 unsigned int count = 0; 576 const unsigned num_sample_bytes = bytes_per_sample(s); 577 578 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 579 async->munge_count += num_bytes; 580 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 581 return num_bytes; 582 } 583 /* don't munge partial samples */ 584 num_bytes -= num_bytes % num_sample_bytes; 585 while (count < num_bytes) { 586 int block_size; 587 588 block_size = num_bytes - count; 589 if (block_size < 0) { 590 dev_warn(s->device->class_dev, 591 "%s: %s: bug! block_size is negative\n", 592 __FILE__, __func__); 593 break; 594 } 595 if ((int)(async->munge_ptr + block_size - 596 async->prealloc_bufsz) > 0) 597 block_size = async->prealloc_bufsz - async->munge_ptr; 598 599 s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, 600 block_size, async->munge_chan); 601 602 smp_wmb(); /* barrier insures data is munged in buffer 603 * before munge_count is incremented */ 604 605 async->munge_chan += block_size / num_sample_bytes; 606 async->munge_chan %= async->cmd.chanlist_len; 607 async->munge_count += block_size; 608 async->munge_ptr += block_size; 609 async->munge_ptr %= async->prealloc_bufsz; 610 count += block_size; 611 } 612 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 613 return count; 614} 615 616unsigned int comedi_buf_write_n_available(struct comedi_async *async) 617{ 618 unsigned int free_end; 619 unsigned int nbytes; 620 621 if (async == NULL) 622 return 0; 623 624 free_end = async->buf_read_count + async->prealloc_bufsz; 625 nbytes = free_end - async->buf_write_alloc_count; 626 nbytes -= nbytes % bytes_per_sample(async->subdevice); 627 /* barrier insures the read of buf_read_count in this 628 query occurs before any following writes to the buffer which 629 might be based on the return value from this query. 630 */ 631 smp_mb(); 632 return nbytes; 633} 634 635/* allocates chunk for the writer from free buffer space */ 636unsigned int comedi_buf_write_alloc(struct comedi_async *async, 637 unsigned int nbytes) 638{ 639 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 640 641 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 642 nbytes = free_end - async->buf_write_alloc_count; 643 644 async->buf_write_alloc_count += nbytes; 645 /* barrier insures the read of buf_read_count above occurs before 646 we write data to the write-alloc'ed buffer space */ 647 smp_mb(); 648 return nbytes; 649} 650EXPORT_SYMBOL(comedi_buf_write_alloc); 651 652/* allocates nothing unless it can completely fulfill the request */ 653unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, 654 unsigned int nbytes) 655{ 656 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 657 658 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 659 nbytes = 0; 660 661 async->buf_write_alloc_count += nbytes; 662 /* barrier insures the read of buf_read_count above occurs before 663 we write data to the write-alloc'ed buffer space */ 664 smp_mb(); 665 return nbytes; 666} 667 668/* transfers a chunk from writer to filled buffer space */ 669unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) 670{ 671 if ((int)(async->buf_write_count + nbytes - 672 async->buf_write_alloc_count) > 0) { 673 dev_info(async->subdevice->device->class_dev, 674 "attempted to write-free more bytes than have been write-allocated.\n"); 675 nbytes = async->buf_write_alloc_count - async->buf_write_count; 676 } 677 async->buf_write_count += nbytes; 678 async->buf_write_ptr += nbytes; 679 comedi_buf_munge(async, async->buf_write_count - async->munge_count); 680 if (async->buf_write_ptr >= async->prealloc_bufsz) 681 async->buf_write_ptr %= async->prealloc_bufsz; 682 683 return nbytes; 684} 685EXPORT_SYMBOL(comedi_buf_write_free); 686 687/* allocates a chunk for the reader from filled (and munged) buffer space */ 688unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) 689{ 690 if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > 691 0) { 692 nbytes = async->munge_count - async->buf_read_alloc_count; 693 } 694 async->buf_read_alloc_count += nbytes; 695 /* barrier insures read of munge_count occurs before we actually read 696 data out of buffer */ 697 smp_rmb(); 698 return nbytes; 699} 700EXPORT_SYMBOL(comedi_buf_read_alloc); 701 702/* transfers control of a chunk from reader to free buffer space */ 703unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) 704{ 705 /* barrier insures data has been read out of 706 * buffer before read count is incremented */ 707 smp_mb(); 708 if ((int)(async->buf_read_count + nbytes - 709 async->buf_read_alloc_count) > 0) { 710 dev_info(async->subdevice->device->class_dev, 711 "attempted to read-free more bytes than have been read-allocated.\n"); 712 nbytes = async->buf_read_alloc_count - async->buf_read_count; 713 } 714 async->buf_read_count += nbytes; 715 async->buf_read_ptr += nbytes; 716 async->buf_read_ptr %= async->prealloc_bufsz; 717 return nbytes; 718} 719EXPORT_SYMBOL(comedi_buf_read_free); 720 721void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, 722 const void *data, unsigned int num_bytes) 723{ 724 unsigned int write_ptr = async->buf_write_ptr + offset; 725 726 if (write_ptr >= async->prealloc_bufsz) 727 write_ptr %= async->prealloc_bufsz; 728 729 while (num_bytes) { 730 unsigned int block_size; 731 732 if (write_ptr + num_bytes > async->prealloc_bufsz) 733 block_size = async->prealloc_bufsz - write_ptr; 734 else 735 block_size = num_bytes; 736 737 memcpy(async->prealloc_buf + write_ptr, data, block_size); 738 739 data += block_size; 740 num_bytes -= block_size; 741 742 write_ptr = 0; 743 } 744} 745EXPORT_SYMBOL(comedi_buf_memcpy_to); 746 747void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, 748 void *dest, unsigned int nbytes) 749{ 750 void *src; 751 unsigned int read_ptr = async->buf_read_ptr + offset; 752 753 if (read_ptr >= async->prealloc_bufsz) 754 read_ptr %= async->prealloc_bufsz; 755 756 while (nbytes) { 757 unsigned int block_size; 758 759 src = async->prealloc_buf + read_ptr; 760 761 if (nbytes >= async->prealloc_bufsz - read_ptr) 762 block_size = async->prealloc_bufsz - read_ptr; 763 else 764 block_size = nbytes; 765 766 memcpy(dest, src, block_size); 767 nbytes -= block_size; 768 dest += block_size; 769 read_ptr = 0; 770 } 771} 772EXPORT_SYMBOL(comedi_buf_memcpy_from); 773 774unsigned int comedi_buf_read_n_available(struct comedi_async *async) 775{ 776 unsigned num_bytes; 777 778 if (async == NULL) 779 return 0; 780 num_bytes = async->munge_count - async->buf_read_count; 781 /* barrier insures the read of munge_count in this 782 query occurs before any following reads of the buffer which 783 might be based on the return value from this query. 784 */ 785 smp_rmb(); 786 return num_bytes; 787} 788EXPORT_SYMBOL(comedi_buf_read_n_available); 789 790int comedi_buf_get(struct comedi_async *async, short *x) 791{ 792 unsigned int n = comedi_buf_read_n_available(async); 793 794 if (n < sizeof(short)) 795 return 0; 796 comedi_buf_read_alloc(async, sizeof(short)); 797 *x = *(short *)(async->prealloc_buf + async->buf_read_ptr); 798 comedi_buf_read_free(async, sizeof(short)); 799 return 1; 800} 801EXPORT_SYMBOL(comedi_buf_get); 802 803int comedi_buf_put(struct comedi_async *async, short x) 804{ 805 unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); 806 807 if (n < sizeof(short)) { 808 async->events |= COMEDI_CB_ERROR; 809 return 0; 810 } 811 *(short *)(async->prealloc_buf + async->buf_write_ptr) = x; 812 comedi_buf_write_free(async, sizeof(short)); 813 return 1; 814} 815EXPORT_SYMBOL(comedi_buf_put); 816 817void comedi_reset_async_buf(struct comedi_async *async) 818{ 819 async->buf_write_alloc_count = 0; 820 async->buf_write_count = 0; 821 async->buf_read_alloc_count = 0; 822 async->buf_read_count = 0; 823 824 async->buf_write_ptr = 0; 825 async->buf_read_ptr = 0; 826 827 async->cur_chan = 0; 828 async->scan_progress = 0; 829 async->munge_chan = 0; 830 async->munge_count = 0; 831 async->munge_ptr = 0; 832 833 async->events = 0; 834} 835 836static int 837comedi_auto_config_helper(struct device *hardware_device, 838 struct comedi_driver *driver, 839 int (*attach_wrapper) (struct comedi_device *, 840 unsigned long), 841 unsigned long context) 842{ 843 int minor; 844 struct comedi_device_file_info *dev_file_info; 845 struct comedi_device *comedi_dev; 846 int ret; 847 848 if (!comedi_autoconfig) 849 return 0; 850 851 minor = comedi_alloc_board_minor(hardware_device); 852 if (minor < 0) 853 return minor; 854 855 dev_file_info = comedi_get_device_file_info(minor); 856 comedi_dev = dev_file_info->device; 857 858 mutex_lock(&comedi_dev->mutex); 859 if (comedi_dev->attached) 860 ret = -EBUSY; 861 else if (!try_module_get(driver->module)) 862 ret = -EIO; 863 else { 864 comedi_set_hw_dev(comedi_dev, hardware_device); 865 /* set comedi_dev->driver here for attach wrapper */ 866 comedi_dev->driver = driver; 867 ret = (*attach_wrapper)(comedi_dev, context); 868 if (ret < 0) { 869 module_put(driver->module); 870 __comedi_device_detach(comedi_dev); 871 } else { 872 ret = comedi_device_postconfig(comedi_dev); 873 } 874 } 875 mutex_unlock(&comedi_dev->mutex); 876 877 if (ret < 0) 878 comedi_free_board_minor(minor); 879 return ret; 880} 881 882static int comedi_auto_config_wrapper(struct comedi_device *dev, 883 unsigned long context) 884{ 885 if (!dev->driver->auto_attach) { 886 dev_warn(dev->class_dev, 887 "BUG! driver '%s' has no auto_attach handler\n", 888 dev->driver->driver_name); 889 return -EINVAL; 890 } 891 return dev->driver->auto_attach(dev, context); 892} 893 894int comedi_auto_config(struct device *hardware_device, 895 struct comedi_driver *driver, unsigned long context) 896{ 897 return comedi_auto_config_helper(hardware_device, driver, 898 comedi_auto_config_wrapper, context); 899} 900EXPORT_SYMBOL_GPL(comedi_auto_config); 901 902void comedi_auto_unconfig(struct device *hardware_device) 903{ 904 int minor; 905 906 if (hardware_device == NULL) 907 return; 908 minor = comedi_find_board_minor(hardware_device); 909 if (minor < 0) 910 return; 911 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS); 912 comedi_free_board_minor(minor); 913} 914EXPORT_SYMBOL_GPL(comedi_auto_unconfig); 915 916/** 917 * comedi_pci_enable() - Enable the PCI device and request the regions. 918 * @pdev: pci_dev struct 919 * @res_name: name for the requested reqource 920 */ 921int comedi_pci_enable(struct pci_dev *pdev, const char *res_name) 922{ 923 int rc; 924 925 rc = pci_enable_device(pdev); 926 if (rc < 0) 927 return rc; 928 929 rc = pci_request_regions(pdev, res_name); 930 if (rc < 0) 931 pci_disable_device(pdev); 932 933 return rc; 934} 935EXPORT_SYMBOL_GPL(comedi_pci_enable); 936 937/** 938 * comedi_pci_disable() - Release the regions and disable the PCI device. 939 * @pdev: pci_dev struct 940 * 941 * This must be matched with a previous successful call to comedi_pci_enable(). 942 */ 943void comedi_pci_disable(struct pci_dev *pdev) 944{ 945 pci_release_regions(pdev); 946 pci_disable_device(pdev); 947} 948EXPORT_SYMBOL_GPL(comedi_pci_disable); 949 950int comedi_pci_auto_config(struct pci_dev *pcidev, struct comedi_driver *driver) 951{ 952 953 if (driver->auto_attach) 954 return comedi_auto_config(&pcidev->dev, driver, 0); 955 else 956 return -EINVAL; 957} 958EXPORT_SYMBOL_GPL(comedi_pci_auto_config); 959 960void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 961{ 962 comedi_auto_unconfig(&pcidev->dev); 963} 964EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); 965 966int comedi_pci_driver_register(struct comedi_driver *comedi_driver, 967 struct pci_driver *pci_driver) 968{ 969 int ret; 970 971 ret = comedi_driver_register(comedi_driver); 972 if (ret < 0) 973 return ret; 974 975 /* FIXME: Remove this test after auditing all comedi pci drivers */ 976 if (!pci_driver->name) 977 pci_driver->name = comedi_driver->driver_name; 978 979 ret = pci_register_driver(pci_driver); 980 if (ret < 0) { 981 comedi_driver_unregister(comedi_driver); 982 return ret; 983 } 984 985 return 0; 986} 987EXPORT_SYMBOL_GPL(comedi_pci_driver_register); 988 989void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver, 990 struct pci_driver *pci_driver) 991{ 992 pci_unregister_driver(pci_driver); 993 comedi_driver_unregister(comedi_driver); 994} 995EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister); 996 997#if IS_ENABLED(CONFIG_USB) 998 999static int comedi_usb_attach_wrapper(struct comedi_device *dev, 1000 unsigned long context) 1001{ 1002 return dev->driver->attach_usb(dev, (struct usb_interface *)context); 1003} 1004 1005static int comedi_new_usb_auto_config(struct usb_interface *intf, 1006 struct comedi_driver *driver) 1007{ 1008 return comedi_auto_config_helper(&intf->dev, driver, 1009 comedi_usb_attach_wrapper, 1010 (unsigned long)intf); 1011} 1012 1013int comedi_usb_auto_config(struct usb_interface *intf, 1014 struct comedi_driver *driver) 1015{ 1016 BUG_ON(intf == NULL); 1017 if (driver->attach_usb) 1018 return comedi_new_usb_auto_config(intf, driver); 1019 else if (driver->auto_attach) 1020 return comedi_auto_config(&intf->dev, driver, 0); 1021 else 1022 return -EINVAL; 1023} 1024EXPORT_SYMBOL_GPL(comedi_usb_auto_config); 1025 1026void comedi_usb_auto_unconfig(struct usb_interface *intf) 1027{ 1028 BUG_ON(intf == NULL); 1029 comedi_auto_unconfig(&intf->dev); 1030} 1031EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig); 1032 1033int comedi_usb_driver_register(struct comedi_driver *comedi_driver, 1034 struct usb_driver *usb_driver) 1035{ 1036 int ret; 1037 1038 ret = comedi_driver_register(comedi_driver); 1039 if (ret < 0) 1040 return ret; 1041 1042 ret = usb_register(usb_driver); 1043 if (ret < 0) { 1044 comedi_driver_unregister(comedi_driver); 1045 return ret; 1046 } 1047 1048 return 0; 1049} 1050EXPORT_SYMBOL_GPL(comedi_usb_driver_register); 1051 1052void comedi_usb_driver_unregister(struct comedi_driver *comedi_driver, 1053 struct usb_driver *usb_driver) 1054{ 1055 usb_deregister(usb_driver); 1056 comedi_driver_unregister(comedi_driver); 1057} 1058EXPORT_SYMBOL_GPL(comedi_usb_driver_unregister); 1059 1060#endif 1061