drivers.c revision 8b9ba6e5efc3213f384cda155861a4f7ae903365
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 "comedi_fops.h" 28#include <linux/device.h> 29#include <linux/module.h> 30#include <linux/pci.h> 31#include <linux/usb.h> 32#include <linux/errno.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 "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 int i; 62 63 dev->n_subdevices = num_subdevices; 64 dev->subdevices = 65 kcalloc(num_subdevices, sizeof(struct comedi_subdevice), 66 GFP_KERNEL); 67 if (!dev->subdevices) 68 return -ENOMEM; 69 for (i = 0; i < num_subdevices; ++i) { 70 dev->subdevices[i].device = dev; 71 dev->subdevices[i].async_dma_dir = DMA_NONE; 72 spin_lock_init(&dev->subdevices[i].spin_lock); 73 dev->subdevices[i].minor = -1; 74 } 75 return 0; 76} 77EXPORT_SYMBOL_GPL(comedi_alloc_subdevices); 78 79static void cleanup_device(struct comedi_device *dev) 80{ 81 int i; 82 struct comedi_subdevice *s; 83 84 if (dev->subdevices) { 85 for (i = 0; i < dev->n_subdevices; i++) { 86 s = dev->subdevices + i; 87 comedi_free_subdevice_minor(s); 88 if (s->async) { 89 comedi_buf_alloc(dev, s, 0); 90 kfree(s->async); 91 } 92 } 93 kfree(dev->subdevices); 94 dev->subdevices = NULL; 95 dev->n_subdevices = 0; 96 } 97 kfree(dev->private); 98 dev->private = NULL; 99 dev->driver = NULL; 100 dev->board_name = NULL; 101 dev->board_ptr = NULL; 102 dev->iobase = 0; 103 dev->irq = 0; 104 dev->read_subdev = NULL; 105 dev->write_subdev = NULL; 106 dev->open = NULL; 107 dev->close = NULL; 108 comedi_set_hw_dev(dev, NULL); 109} 110 111static void __comedi_device_detach(struct comedi_device *dev) 112{ 113 dev->attached = 0; 114 if (dev->driver) 115 dev->driver->detach(dev); 116 else 117 printk(KERN_WARNING 118 "BUG: dev->driver=NULL in comedi_device_detach()\n"); 119 cleanup_device(dev); 120} 121 122void comedi_device_detach(struct comedi_device *dev) 123{ 124 if (!dev->attached) 125 return; 126 __comedi_device_detach(dev); 127} 128 129/* do a little post-config cleanup */ 130/* called with module refcount incremented, decrements it */ 131static int comedi_device_postconfig(struct comedi_device *dev) 132{ 133 int ret = postconfig(dev); 134 module_put(dev->driver->module); 135 if (ret < 0) { 136 __comedi_device_detach(dev); 137 return ret; 138 } 139 if (!dev->board_name) { 140 printk(KERN_WARNING "BUG: dev->board_name=<%p>\n", 141 dev->board_name); 142 dev->board_name = "BUG"; 143 } 144 smp_wmb(); 145 dev->attached = 1; 146 return 0; 147} 148 149int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 150{ 151 struct comedi_driver *driv; 152 int ret; 153 154 if (dev->attached) 155 return -EBUSY; 156 157 for (driv = comedi_drivers; driv; driv = driv->next) { 158 if (!try_module_get(driv->module)) { 159 printk(KERN_INFO "comedi: failed to increment module count, skipping\n"); 160 continue; 161 } 162 if (driv->num_names) { 163 dev->board_ptr = comedi_recognize(driv, it->board_name); 164 if (dev->board_ptr) 165 break; 166 } else if (strcmp(driv->driver_name, it->board_name)) 167 break; 168 module_put(driv->module); 169 } 170 if (driv == NULL) { 171 /* recognize has failed if we get here */ 172 /* report valid board names before returning error */ 173 for (driv = comedi_drivers; driv; driv = driv->next) { 174 if (!try_module_get(driv->module)) { 175 printk(KERN_INFO 176 "comedi: failed to increment module count\n"); 177 continue; 178 } 179 comedi_report_boards(driv); 180 module_put(driv->module); 181 } 182 return -EIO; 183 } 184 /* initialize dev->driver here so 185 * comedi_error() can be called from attach */ 186 dev->driver = driv; 187 ret = driv->attach(dev, it); 188 if (ret < 0) { 189 module_put(dev->driver->module); 190 __comedi_device_detach(dev); 191 return ret; 192 } 193 return comedi_device_postconfig(dev); 194} 195 196int comedi_driver_register(struct comedi_driver *driver) 197{ 198 driver->next = comedi_drivers; 199 comedi_drivers = driver; 200 201 return 0; 202} 203EXPORT_SYMBOL(comedi_driver_register); 204 205int comedi_driver_unregister(struct comedi_driver *driver) 206{ 207 struct comedi_driver *prev; 208 int i; 209 210 /* check for devices using this driver */ 211 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 212 struct comedi_device_file_info *dev_file_info = 213 comedi_get_device_file_info(i); 214 struct comedi_device *dev; 215 216 if (dev_file_info == NULL) 217 continue; 218 dev = dev_file_info->device; 219 220 mutex_lock(&dev->mutex); 221 if (dev->attached && dev->driver == driver) { 222 if (dev->use_count) 223 printk(KERN_WARNING "BUG! detaching device with use_count=%d\n", 224 dev->use_count); 225 comedi_device_detach(dev); 226 } 227 mutex_unlock(&dev->mutex); 228 } 229 230 if (comedi_drivers == driver) { 231 comedi_drivers = driver->next; 232 return 0; 233 } 234 235 for (prev = comedi_drivers; prev->next; prev = prev->next) { 236 if (prev->next == driver) { 237 prev->next = driver->next; 238 return 0; 239 } 240 } 241 return -EINVAL; 242} 243EXPORT_SYMBOL(comedi_driver_unregister); 244 245static int postconfig(struct comedi_device *dev) 246{ 247 int i; 248 struct comedi_subdevice *s; 249 struct comedi_async *async = NULL; 250 int ret; 251 252 for (i = 0; i < dev->n_subdevices; i++) { 253 s = dev->subdevices + i; 254 255 if (s->type == COMEDI_SUBD_UNUSED) 256 continue; 257 258 if (s->len_chanlist == 0) 259 s->len_chanlist = 1; 260 261 if (s->do_cmd) { 262 unsigned int buf_size; 263 264 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 265 SDF_CMD_WRITE)) == 0); 266 BUG_ON(!s->do_cmdtest); 267 268 async = 269 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 270 if (async == NULL) { 271 printk(KERN_INFO 272 "failed to allocate async struct\n"); 273 return -ENOMEM; 274 } 275 init_waitqueue_head(&async->wait_head); 276 async->subdevice = s; 277 s->async = async; 278 279 async->max_bufsize = 280 comedi_default_buf_maxsize_kb * 1024; 281 buf_size = comedi_default_buf_size_kb * 1024; 282 if (buf_size > async->max_bufsize) 283 buf_size = async->max_bufsize; 284 285 async->prealloc_buf = NULL; 286 async->prealloc_bufsz = 0; 287 if (comedi_buf_alloc(dev, s, buf_size) < 0) { 288 printk(KERN_INFO "Buffer allocation failed\n"); 289 return -ENOMEM; 290 } 291 if (s->buf_change) { 292 ret = s->buf_change(dev, s, buf_size); 293 if (ret < 0) 294 return ret; 295 } 296 comedi_alloc_subdevice_minor(dev, s); 297 } 298 299 if (!s->range_table && !s->range_table_list) 300 s->range_table = &range_unknown; 301 302 if (!s->insn_read && s->insn_bits) 303 s->insn_read = insn_rw_emulate_bits; 304 if (!s->insn_write && s->insn_bits) 305 s->insn_write = insn_rw_emulate_bits; 306 307 if (!s->insn_read) 308 s->insn_read = insn_inval; 309 if (!s->insn_write) 310 s->insn_write = insn_inval; 311 if (!s->insn_bits) 312 s->insn_bits = insn_inval; 313 if (!s->insn_config) 314 s->insn_config = insn_inval; 315 316 if (!s->poll) 317 s->poll = poll_invalid; 318 } 319 320 return 0; 321} 322 323/* 324 * Generic recognize function for drivers that register their supported 325 * board names. 326 * 327 * 'driv->board_name' points to a 'const char *' member within the 328 * zeroth element of an array of some private board information 329 * structure, say 'struct foo_board' containing a member 'const char 330 * *board_name' that is initialized to point to a board name string that 331 * is one of the candidates matched against this function's 'name' 332 * parameter. 333 * 334 * 'driv->offset' is the size of the private board information 335 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is 336 * the length of the array of private board information structures. 337 * 338 * If one of the board names in the array of private board information 339 * structures matches the name supplied to this function, the function 340 * returns a pointer to the pointer to the board name, otherwise it 341 * returns NULL. The return value ends up in the 'board_ptr' member of 342 * a 'struct comedi_device' that the low-level comedi driver's 343 * 'attach()' hook can convert to a point to a particular element of its 344 * array of private board information structures by subtracting the 345 * offset of the member that points to the board name. (No subtraction 346 * is required if the board name pointer is the first member of the 347 * private board information structure, which is generally the case.) 348 */ 349static void *comedi_recognize(struct comedi_driver *driv, const char *name) 350{ 351 char **name_ptr = (char **)driv->board_name; 352 int i; 353 354 for (i = 0; i < driv->num_names; i++) { 355 if (strcmp(*name_ptr, name) == 0) 356 return name_ptr; 357 name_ptr = (void *)name_ptr + driv->offset; 358 } 359 360 return NULL; 361} 362 363static void comedi_report_boards(struct comedi_driver *driv) 364{ 365 unsigned int i; 366 const char *const *name_ptr; 367 368 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 369 driv->driver_name); 370 371 name_ptr = driv->board_name; 372 for (i = 0; i < driv->num_names; i++) { 373 printk(KERN_INFO " %s\n", *name_ptr); 374 name_ptr = (const char **)((char *)name_ptr + driv->offset); 375 } 376 377 if (driv->num_names == 0) 378 printk(KERN_INFO " %s\n", driv->driver_name); 379} 380 381static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 382{ 383 return -EINVAL; 384} 385 386int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 387 struct comedi_insn *insn, unsigned int *data) 388{ 389 return -EINVAL; 390} 391 392static int insn_rw_emulate_bits(struct comedi_device *dev, 393 struct comedi_subdevice *s, 394 struct comedi_insn *insn, unsigned int *data) 395{ 396 struct comedi_insn new_insn; 397 int ret; 398 static const unsigned channels_per_bitfield = 32; 399 400 unsigned chan = CR_CHAN(insn->chanspec); 401 const unsigned base_bitfield_channel = 402 (chan < channels_per_bitfield) ? 0 : chan; 403 unsigned int new_data[2]; 404 memset(new_data, 0, sizeof(new_data)); 405 memset(&new_insn, 0, sizeof(new_insn)); 406 new_insn.insn = INSN_BITS; 407 new_insn.chanspec = base_bitfield_channel; 408 new_insn.n = 2; 409 new_insn.data = new_data; 410 new_insn.subdev = insn->subdev; 411 412 if (insn->insn == INSN_WRITE) { 413 if (!(s->subdev_flags & SDF_WRITABLE)) 414 return -EINVAL; 415 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 416 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 417 : 0; /* bits */ 418 } 419 420 ret = s->insn_bits(dev, s, &new_insn, new_data); 421 if (ret < 0) 422 return ret; 423 424 if (insn->insn == INSN_READ) 425 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 426 427 return 1; 428} 429 430int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 431 unsigned long new_size) 432{ 433 struct comedi_async *async = s->async; 434 435 /* Round up new_size to multiple of PAGE_SIZE */ 436 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 437 438 /* if no change is required, do nothing */ 439 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 440 return 0; 441 442 /* deallocate old buffer */ 443 if (async->prealloc_buf) { 444 vunmap(async->prealloc_buf); 445 async->prealloc_buf = NULL; 446 async->prealloc_bufsz = 0; 447 } 448 if (async->buf_page_list) { 449 unsigned i; 450 for (i = 0; i < async->n_buf_pages; ++i) { 451 if (async->buf_page_list[i].virt_addr) { 452 clear_bit(PG_reserved, 453 &(virt_to_page(async->buf_page_list[i]. 454 virt_addr)->flags)); 455 if (s->async_dma_dir != DMA_NONE) { 456 dma_free_coherent(dev->hw_dev, 457 PAGE_SIZE, 458 async-> 459 buf_page_list 460 [i].virt_addr, 461 async-> 462 buf_page_list 463 [i].dma_addr); 464 } else { 465 free_page((unsigned long) 466 async->buf_page_list[i]. 467 virt_addr); 468 } 469 } 470 } 471 vfree(async->buf_page_list); 472 async->buf_page_list = NULL; 473 async->n_buf_pages = 0; 474 } 475 /* allocate new buffer */ 476 if (new_size) { 477 unsigned i = 0; 478 unsigned n_pages = new_size >> PAGE_SHIFT; 479 struct page **pages = NULL; 480 481 async->buf_page_list = 482 vzalloc(sizeof(struct comedi_buf_page) * n_pages); 483 if (async->buf_page_list) 484 pages = vmalloc(sizeof(struct page *) * n_pages); 485 486 if (pages) { 487 for (i = 0; i < n_pages; i++) { 488 if (s->async_dma_dir != DMA_NONE) { 489 async->buf_page_list[i].virt_addr = 490 dma_alloc_coherent(dev->hw_dev, 491 PAGE_SIZE, 492 &async-> 493 buf_page_list 494 [i].dma_addr, 495 GFP_KERNEL | 496 __GFP_COMP); 497 } else { 498 async->buf_page_list[i].virt_addr = 499 (void *) 500 get_zeroed_page(GFP_KERNEL); 501 } 502 if (async->buf_page_list[i].virt_addr == NULL) 503 break; 504 505 set_bit(PG_reserved, 506 &(virt_to_page(async->buf_page_list[i]. 507 virt_addr)->flags)); 508 pages[i] = virt_to_page(async->buf_page_list[i]. 509 virt_addr); 510 } 511 } 512 if (i == n_pages) { 513 async->prealloc_buf = 514#ifdef PAGE_KERNEL_NOCACHE 515 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 516#else 517 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL); 518#endif 519 } 520 vfree(pages); 521 522 if (async->prealloc_buf == NULL) { 523 /* Some allocation failed above. */ 524 if (async->buf_page_list) { 525 for (i = 0; i < n_pages; i++) { 526 if (async->buf_page_list[i].virt_addr == 527 NULL) { 528 break; 529 } 530 clear_bit(PG_reserved, 531 &(virt_to_page(async-> 532 buf_page_list[i]. 533 virt_addr)->flags)); 534 if (s->async_dma_dir != DMA_NONE) { 535 dma_free_coherent(dev->hw_dev, 536 PAGE_SIZE, 537 async-> 538 buf_page_list 539 [i].virt_addr, 540 async-> 541 buf_page_list 542 [i].dma_addr); 543 } else { 544 free_page((unsigned long) 545 async->buf_page_list 546 [i].virt_addr); 547 } 548 } 549 vfree(async->buf_page_list); 550 async->buf_page_list = NULL; 551 } 552 return -ENOMEM; 553 } 554 async->n_buf_pages = n_pages; 555 } 556 async->prealloc_bufsz = new_size; 557 558 return 0; 559} 560 561/* munging is applied to data by core as it passes between user 562 * and kernel space */ 563static unsigned int comedi_buf_munge(struct comedi_async *async, 564 unsigned int num_bytes) 565{ 566 struct comedi_subdevice *s = async->subdevice; 567 unsigned int count = 0; 568 const unsigned num_sample_bytes = bytes_per_sample(s); 569 570 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 571 async->munge_count += num_bytes; 572 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 573 return num_bytes; 574 } 575 /* don't munge partial samples */ 576 num_bytes -= num_bytes % num_sample_bytes; 577 while (count < num_bytes) { 578 int block_size; 579 580 block_size = num_bytes - count; 581 if (block_size < 0) { 582 printk(KERN_WARNING 583 "%s: %s: bug! block_size is negative\n", 584 __FILE__, __func__); 585 break; 586 } 587 if ((int)(async->munge_ptr + block_size - 588 async->prealloc_bufsz) > 0) 589 block_size = async->prealloc_bufsz - async->munge_ptr; 590 591 s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, 592 block_size, async->munge_chan); 593 594 smp_wmb(); /* barrier insures data is munged in buffer 595 * before munge_count is incremented */ 596 597 async->munge_chan += block_size / num_sample_bytes; 598 async->munge_chan %= async->cmd.chanlist_len; 599 async->munge_count += block_size; 600 async->munge_ptr += block_size; 601 async->munge_ptr %= async->prealloc_bufsz; 602 count += block_size; 603 } 604 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 605 return count; 606} 607 608unsigned int comedi_buf_write_n_available(struct comedi_async *async) 609{ 610 unsigned int free_end; 611 unsigned int nbytes; 612 613 if (async == NULL) 614 return 0; 615 616 free_end = async->buf_read_count + async->prealloc_bufsz; 617 nbytes = free_end - async->buf_write_alloc_count; 618 nbytes -= nbytes % bytes_per_sample(async->subdevice); 619 /* barrier insures the read of buf_read_count in this 620 query occurs before any following writes to the buffer which 621 might be based on the return value from this query. 622 */ 623 smp_mb(); 624 return nbytes; 625} 626 627/* allocates chunk for the writer from free buffer space */ 628unsigned int comedi_buf_write_alloc(struct comedi_async *async, 629 unsigned int nbytes) 630{ 631 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 632 633 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 634 nbytes = free_end - async->buf_write_alloc_count; 635 636 async->buf_write_alloc_count += nbytes; 637 /* barrier insures the read of buf_read_count above occurs before 638 we write data to the write-alloc'ed buffer space */ 639 smp_mb(); 640 return nbytes; 641} 642EXPORT_SYMBOL(comedi_buf_write_alloc); 643 644/* allocates nothing unless it can completely fulfill the request */ 645unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, 646 unsigned int nbytes) 647{ 648 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 649 650 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 651 nbytes = 0; 652 653 async->buf_write_alloc_count += nbytes; 654 /* barrier insures the read of buf_read_count above occurs before 655 we write data to the write-alloc'ed buffer space */ 656 smp_mb(); 657 return nbytes; 658} 659 660/* transfers a chunk from writer to filled buffer space */ 661unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) 662{ 663 if ((int)(async->buf_write_count + nbytes - 664 async->buf_write_alloc_count) > 0) { 665 printk(KERN_INFO "comedi: attempted to write-free more bytes than have been write-allocated.\n"); 666 nbytes = async->buf_write_alloc_count - async->buf_write_count; 667 } 668 async->buf_write_count += nbytes; 669 async->buf_write_ptr += nbytes; 670 comedi_buf_munge(async, async->buf_write_count - async->munge_count); 671 if (async->buf_write_ptr >= async->prealloc_bufsz) 672 async->buf_write_ptr %= async->prealloc_bufsz; 673 674 return nbytes; 675} 676EXPORT_SYMBOL(comedi_buf_write_free); 677 678/* allocates a chunk for the reader from filled (and munged) buffer space */ 679unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) 680{ 681 if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > 682 0) { 683 nbytes = async->munge_count - async->buf_read_alloc_count; 684 } 685 async->buf_read_alloc_count += nbytes; 686 /* barrier insures read of munge_count occurs before we actually read 687 data out of buffer */ 688 smp_rmb(); 689 return nbytes; 690} 691EXPORT_SYMBOL(comedi_buf_read_alloc); 692 693/* transfers control of a chunk from reader to free buffer space */ 694unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) 695{ 696 /* barrier insures data has been read out of 697 * buffer before read count is incremented */ 698 smp_mb(); 699 if ((int)(async->buf_read_count + nbytes - 700 async->buf_read_alloc_count) > 0) { 701 printk(KERN_INFO 702 "comedi: attempted to read-free more bytes than have been read-allocated.\n"); 703 nbytes = async->buf_read_alloc_count - async->buf_read_count; 704 } 705 async->buf_read_count += nbytes; 706 async->buf_read_ptr += nbytes; 707 async->buf_read_ptr %= async->prealloc_bufsz; 708 return nbytes; 709} 710EXPORT_SYMBOL(comedi_buf_read_free); 711 712void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, 713 const void *data, unsigned int num_bytes) 714{ 715 unsigned int write_ptr = async->buf_write_ptr + offset; 716 717 if (write_ptr >= async->prealloc_bufsz) 718 write_ptr %= async->prealloc_bufsz; 719 720 while (num_bytes) { 721 unsigned int block_size; 722 723 if (write_ptr + num_bytes > async->prealloc_bufsz) 724 block_size = async->prealloc_bufsz - write_ptr; 725 else 726 block_size = num_bytes; 727 728 memcpy(async->prealloc_buf + write_ptr, data, block_size); 729 730 data += block_size; 731 num_bytes -= block_size; 732 733 write_ptr = 0; 734 } 735} 736EXPORT_SYMBOL(comedi_buf_memcpy_to); 737 738void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, 739 void *dest, unsigned int nbytes) 740{ 741 void *src; 742 unsigned int read_ptr = async->buf_read_ptr + offset; 743 744 if (read_ptr >= async->prealloc_bufsz) 745 read_ptr %= async->prealloc_bufsz; 746 747 while (nbytes) { 748 unsigned int block_size; 749 750 src = async->prealloc_buf + read_ptr; 751 752 if (nbytes >= async->prealloc_bufsz - read_ptr) 753 block_size = async->prealloc_bufsz - read_ptr; 754 else 755 block_size = nbytes; 756 757 memcpy(dest, src, block_size); 758 nbytes -= block_size; 759 dest += block_size; 760 read_ptr = 0; 761 } 762} 763EXPORT_SYMBOL(comedi_buf_memcpy_from); 764 765unsigned int comedi_buf_read_n_available(struct comedi_async *async) 766{ 767 unsigned num_bytes; 768 769 if (async == NULL) 770 return 0; 771 num_bytes = async->munge_count - async->buf_read_count; 772 /* barrier insures the read of munge_count in this 773 query occurs before any following reads of the buffer which 774 might be based on the return value from this query. 775 */ 776 smp_rmb(); 777 return num_bytes; 778} 779EXPORT_SYMBOL(comedi_buf_read_n_available); 780 781int comedi_buf_get(struct comedi_async *async, short *x) 782{ 783 unsigned int n = comedi_buf_read_n_available(async); 784 785 if (n < sizeof(short)) 786 return 0; 787 comedi_buf_read_alloc(async, sizeof(short)); 788 *x = *(short *)(async->prealloc_buf + async->buf_read_ptr); 789 comedi_buf_read_free(async, sizeof(short)); 790 return 1; 791} 792EXPORT_SYMBOL(comedi_buf_get); 793 794int comedi_buf_put(struct comedi_async *async, short x) 795{ 796 unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); 797 798 if (n < sizeof(short)) { 799 async->events |= COMEDI_CB_ERROR; 800 return 0; 801 } 802 *(short *)(async->prealloc_buf + async->buf_write_ptr) = x; 803 comedi_buf_write_free(async, sizeof(short)); 804 return 1; 805} 806EXPORT_SYMBOL(comedi_buf_put); 807 808void comedi_reset_async_buf(struct comedi_async *async) 809{ 810 async->buf_write_alloc_count = 0; 811 async->buf_write_count = 0; 812 async->buf_read_alloc_count = 0; 813 async->buf_read_count = 0; 814 815 async->buf_write_ptr = 0; 816 async->buf_read_ptr = 0; 817 818 async->cur_chan = 0; 819 async->scan_progress = 0; 820 async->munge_chan = 0; 821 async->munge_count = 0; 822 async->munge_ptr = 0; 823 824 async->events = 0; 825} 826 827static int 828comedi_auto_config_helper(struct device *hardware_device, 829 struct comedi_driver *driver, 830 int (*attach_wrapper) (struct comedi_device *, 831 void *), void *context) 832{ 833 int minor; 834 struct comedi_device_file_info *dev_file_info; 835 struct comedi_device *comedi_dev; 836 int ret; 837 838 if (!comedi_autoconfig) 839 return 0; 840 841 minor = comedi_alloc_board_minor(hardware_device); 842 if (minor < 0) 843 return minor; 844 845 dev_file_info = comedi_get_device_file_info(minor); 846 comedi_dev = dev_file_info->device; 847 848 mutex_lock(&comedi_dev->mutex); 849 if (comedi_dev->attached) 850 ret = -EBUSY; 851 else if (!try_module_get(driver->module)) { 852 printk(KERN_INFO "comedi: failed to increment module count\n"); 853 ret = -EIO; 854 } else { 855 /* set comedi_dev->driver here for attach wrapper */ 856 comedi_dev->driver = driver; 857 ret = (*attach_wrapper)(comedi_dev, context); 858 if (ret < 0) { 859 module_put(driver->module); 860 __comedi_device_detach(comedi_dev); 861 } else { 862 ret = comedi_device_postconfig(comedi_dev); 863 } 864 } 865 mutex_unlock(&comedi_dev->mutex); 866 867 if (ret < 0) 868 comedi_free_board_minor(minor); 869 return ret; 870} 871 872static int comedi_auto_config_wrapper(struct comedi_device *dev, void *context) 873{ 874 struct comedi_devconfig *it = context; 875 struct comedi_driver *driv = dev->driver; 876 877 if (driv->num_names) { 878 /* look for generic board entry matching driver name, which 879 * has already been copied to it->board_name */ 880 dev->board_ptr = comedi_recognize(driv, it->board_name); 881 if (dev->board_ptr == NULL) { 882 printk(KERN_WARNING 883 "comedi: auto config failed to find board entry" 884 " '%s' for driver '%s'\n", it->board_name, 885 driv->driver_name); 886 comedi_report_boards(driv); 887 return -EINVAL; 888 } 889 } 890 return driv->attach(dev, it); 891} 892 893static int comedi_auto_config(struct device *hardware_device, 894 struct comedi_driver *driver, const int *options, 895 unsigned num_options) 896{ 897 struct comedi_devconfig it; 898 899 memset(&it, 0, sizeof(it)); 900 strncpy(it.board_name, driver->driver_name, COMEDI_NAMELEN); 901 it.board_name[COMEDI_NAMELEN - 1] = '\0'; 902 BUG_ON(num_options > COMEDI_NDEVCONFOPTS); 903 memcpy(it.options, options, num_options * sizeof(int)); 904 return comedi_auto_config_helper(hardware_device, driver, 905 comedi_auto_config_wrapper, &it); 906} 907 908static void comedi_auto_unconfig(struct device *hardware_device) 909{ 910 int minor; 911 912 if (hardware_device == NULL) 913 return; 914 minor = comedi_find_board_minor(hardware_device); 915 if (minor < 0) 916 return; 917 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS); 918 comedi_free_board_minor(minor); 919} 920 921/** 922 * comedi_pci_enable() - Enable the PCI device and request the regions. 923 * @pdev: pci_dev struct 924 * @res_name: name for the requested reqource 925 */ 926int comedi_pci_enable(struct pci_dev *pdev, const char *res_name) 927{ 928 int rc; 929 930 rc = pci_enable_device(pdev); 931 if (rc < 0) 932 return rc; 933 934 rc = pci_request_regions(pdev, res_name); 935 if (rc < 0) 936 pci_disable_device(pdev); 937 938 return rc; 939} 940EXPORT_SYMBOL_GPL(comedi_pci_enable); 941 942/** 943 * comedi_pci_disable() - Release the regions and disable the PCI device. 944 * @pdev: pci_dev struct 945 * 946 * This must be matched with a previous successful call to comedi_pci_enable(). 947 */ 948void comedi_pci_disable(struct pci_dev *pdev) 949{ 950 pci_release_regions(pdev); 951 pci_disable_device(pdev); 952} 953EXPORT_SYMBOL_GPL(comedi_pci_disable); 954 955static int comedi_old_pci_auto_config(struct pci_dev *pcidev, 956 struct comedi_driver *driver) 957{ 958 int options[2]; 959 960 /* pci bus */ 961 options[0] = pcidev->bus->number; 962 /* pci slot */ 963 options[1] = PCI_SLOT(pcidev->devfn); 964 965 return comedi_auto_config(&pcidev->dev, driver, 966 options, ARRAY_SIZE(options)); 967} 968 969static int comedi_pci_attach_wrapper(struct comedi_device *dev, void *pcidev) 970{ 971 return dev->driver->attach_pci(dev, pcidev); 972} 973 974static int comedi_new_pci_auto_config(struct pci_dev *pcidev, 975 struct comedi_driver *driver) 976{ 977 return comedi_auto_config_helper(&pcidev->dev, driver, 978 comedi_pci_attach_wrapper, pcidev); 979} 980 981int comedi_pci_auto_config(struct pci_dev *pcidev, struct comedi_driver *driver) 982{ 983 984 if (driver->attach_pci) 985 return comedi_new_pci_auto_config(pcidev, driver); 986 else 987 return comedi_old_pci_auto_config(pcidev, driver); 988} 989EXPORT_SYMBOL_GPL(comedi_pci_auto_config); 990 991void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 992{ 993 comedi_auto_unconfig(&pcidev->dev); 994} 995EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); 996 997int comedi_pci_driver_register(struct comedi_driver *comedi_driver, 998 struct pci_driver *pci_driver) 999{ 1000 int ret; 1001 1002 ret = comedi_driver_register(comedi_driver); 1003 if (ret < 0) 1004 return ret; 1005 1006 /* FIXME: Remove this test after auditing all comedi pci drivers */ 1007 if (!pci_driver->name) 1008 pci_driver->name = comedi_driver->driver_name; 1009 1010 ret = pci_register_driver(pci_driver); 1011 if (ret < 0) { 1012 comedi_driver_unregister(comedi_driver); 1013 return ret; 1014 } 1015 1016 return 0; 1017} 1018EXPORT_SYMBOL_GPL(comedi_pci_driver_register); 1019 1020void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver, 1021 struct pci_driver *pci_driver) 1022{ 1023 pci_unregister_driver(pci_driver); 1024 comedi_driver_unregister(comedi_driver); 1025} 1026EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister); 1027 1028static int comedi_old_usb_auto_config(struct usb_interface *intf, 1029 struct comedi_driver *driver) 1030{ 1031 return comedi_auto_config(&intf->dev, driver, NULL, 0); 1032} 1033 1034static int comedi_usb_attach_wrapper(struct comedi_device *dev, void *intf) 1035{ 1036 return dev->driver->attach_usb(dev, intf); 1037} 1038 1039static int comedi_new_usb_auto_config(struct usb_interface *intf, 1040 struct comedi_driver *driver) 1041{ 1042 return comedi_auto_config_helper(&intf->dev, driver, 1043 comedi_usb_attach_wrapper, intf); 1044} 1045 1046int comedi_usb_auto_config(struct usb_interface *intf, 1047 struct comedi_driver *driver) 1048{ 1049 BUG_ON(intf == NULL); 1050 if (driver->attach_usb) 1051 return comedi_new_usb_auto_config(intf, driver); 1052 else 1053 return comedi_old_usb_auto_config(intf, driver); 1054} 1055EXPORT_SYMBOL_GPL(comedi_usb_auto_config); 1056 1057void comedi_usb_auto_unconfig(struct usb_interface *intf) 1058{ 1059 BUG_ON(intf == NULL); 1060 comedi_auto_unconfig(&intf->dev); 1061} 1062EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig); 1063 1064int comedi_usb_driver_register(struct comedi_driver *comedi_driver, 1065 struct usb_driver *usb_driver) 1066{ 1067 int ret; 1068 1069 ret = comedi_driver_register(comedi_driver); 1070 if (ret < 0) 1071 return ret; 1072 1073 ret = usb_register(usb_driver); 1074 if (ret < 0) { 1075 comedi_driver_unregister(comedi_driver); 1076 return ret; 1077 } 1078 1079 return 0; 1080} 1081EXPORT_SYMBOL_GPL(comedi_usb_driver_register); 1082 1083void comedi_usb_driver_unregister(struct comedi_driver *comedi_driver, 1084 struct usb_driver *usb_driver) 1085{ 1086 usb_deregister(usb_driver); 1087 comedi_driver_unregister(comedi_driver); 1088} 1089EXPORT_SYMBOL_GPL(comedi_usb_driver_unregister); 1090