drivers.c revision 67b0e64a7b219550cc3378800f680e2bb86a10f9
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#include <asm/system.h> 46 47#include "comedidev.h" 48#include "internal.h" 49 50static int postconfig(struct comedi_device *dev); 51static int insn_rw_emulate_bits(struct comedi_device *dev, 52 struct comedi_subdevice *s, 53 struct comedi_insn *insn, unsigned int *data); 54static void *comedi_recognize(struct comedi_driver *driv, const char *name); 55static void comedi_report_boards(struct comedi_driver *driv); 56static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s); 57 58struct comedi_driver *comedi_drivers; 59 60static void cleanup_device(struct comedi_device *dev) 61{ 62 int i; 63 struct comedi_subdevice *s; 64 65 if (dev->subdevices) { 66 for (i = 0; i < dev->n_subdevices; i++) { 67 s = dev->subdevices + i; 68 comedi_free_subdevice_minor(s); 69 if (s->async) { 70 comedi_buf_alloc(dev, s, 0); 71 kfree(s->async); 72 } 73 } 74 kfree(dev->subdevices); 75 dev->subdevices = NULL; 76 dev->n_subdevices = 0; 77 } 78 kfree(dev->private); 79 dev->private = NULL; 80 dev->driver = NULL; 81 dev->board_name = NULL; 82 dev->board_ptr = NULL; 83 dev->iobase = 0; 84 dev->irq = 0; 85 dev->read_subdev = NULL; 86 dev->write_subdev = NULL; 87 dev->open = NULL; 88 dev->close = NULL; 89 comedi_set_hw_dev(dev, NULL); 90} 91 92static void __comedi_device_detach(struct comedi_device *dev) 93{ 94 dev->attached = 0; 95 if (dev->driver) 96 dev->driver->detach(dev); 97 else 98 printk(KERN_WARNING 99 "BUG: dev->driver=NULL in comedi_device_detach()\n"); 100 cleanup_device(dev); 101} 102 103void comedi_device_detach(struct comedi_device *dev) 104{ 105 if (!dev->attached) 106 return; 107 __comedi_device_detach(dev); 108} 109 110int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 111{ 112 struct comedi_driver *driv; 113 int ret; 114 115 if (dev->attached) 116 return -EBUSY; 117 118 for (driv = comedi_drivers; driv; driv = driv->next) { 119 if (!try_module_get(driv->module)) { 120 printk 121 (KERN_INFO "comedi: failed to increment module count, skipping\n"); 122 continue; 123 } 124 if (driv->num_names) { 125 dev->board_ptr = comedi_recognize(driv, it->board_name); 126 if (dev->board_ptr == NULL) { 127 module_put(driv->module); 128 continue; 129 } 130 } else { 131 if (strcmp(driv->driver_name, it->board_name)) { 132 module_put(driv->module); 133 continue; 134 } 135 } 136 /* initialize dev->driver here so 137 * comedi_error() can be called from attach */ 138 dev->driver = driv; 139 ret = driv->attach(dev, it); 140 if (ret < 0) { 141 module_put(dev->driver->module); 142 __comedi_device_detach(dev); 143 return ret; 144 } 145 goto attached; 146 } 147 148 /* recognize has failed if we get here */ 149 /* report valid board names before returning error */ 150 for (driv = comedi_drivers; driv; driv = driv->next) { 151 if (!try_module_get(driv->module)) { 152 printk(KERN_INFO 153 "comedi: failed to increment module count\n"); 154 continue; 155 } 156 comedi_report_boards(driv); 157 module_put(driv->module); 158 } 159 return -EIO; 160 161attached: 162 /* do a little post-config cleanup */ 163 ret = postconfig(dev); 164 module_put(dev->driver->module); 165 if (ret < 0) { 166 __comedi_device_detach(dev); 167 return ret; 168 } 169 170 if (!dev->board_name) { 171 printk(KERN_WARNING "BUG: dev->board_name=<%p>\n", 172 dev->board_name); 173 dev->board_name = "BUG"; 174 } 175 smp_wmb(); 176 dev->attached = 1; 177 178 return 0; 179} 180 181int comedi_driver_register(struct comedi_driver *driver) 182{ 183 driver->next = comedi_drivers; 184 comedi_drivers = driver; 185 186 return 0; 187} 188EXPORT_SYMBOL(comedi_driver_register); 189 190int comedi_driver_unregister(struct comedi_driver *driver) 191{ 192 struct comedi_driver *prev; 193 int i; 194 195 /* check for devices using this driver */ 196 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 197 struct comedi_device_file_info *dev_file_info = 198 comedi_get_device_file_info(i); 199 struct comedi_device *dev; 200 201 if (dev_file_info == NULL) 202 continue; 203 dev = dev_file_info->device; 204 205 mutex_lock(&dev->mutex); 206 if (dev->attached && dev->driver == driver) { 207 if (dev->use_count) 208 printk 209 (KERN_WARNING "BUG! detaching device with use_count=%d\n", 210 dev->use_count); 211 comedi_device_detach(dev); 212 } 213 mutex_unlock(&dev->mutex); 214 } 215 216 if (comedi_drivers == driver) { 217 comedi_drivers = driver->next; 218 return 0; 219 } 220 221 for (prev = comedi_drivers; prev->next; prev = prev->next) { 222 if (prev->next == driver) { 223 prev->next = driver->next; 224 return 0; 225 } 226 } 227 return -EINVAL; 228} 229EXPORT_SYMBOL(comedi_driver_unregister); 230 231static int postconfig(struct comedi_device *dev) 232{ 233 int i; 234 struct comedi_subdevice *s; 235 struct comedi_async *async = NULL; 236 int ret; 237 238 for (i = 0; i < dev->n_subdevices; i++) { 239 s = dev->subdevices + i; 240 241 if (s->type == COMEDI_SUBD_UNUSED) 242 continue; 243 244 if (s->len_chanlist == 0) 245 s->len_chanlist = 1; 246 247 if (s->do_cmd) { 248 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 249 SDF_CMD_WRITE)) == 0); 250 BUG_ON(!s->do_cmdtest); 251 252 async = 253 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 254 if (async == NULL) { 255 printk(KERN_INFO 256 "failed to allocate async struct\n"); 257 return -ENOMEM; 258 } 259 init_waitqueue_head(&async->wait_head); 260 async->subdevice = s; 261 s->async = async; 262 263#define DEFAULT_BUF_MAXSIZE (64*1024) 264#define DEFAULT_BUF_SIZE (64*1024) 265 266 async->max_bufsize = DEFAULT_BUF_MAXSIZE; 267 268 async->prealloc_buf = NULL; 269 async->prealloc_bufsz = 0; 270 if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) { 271 printk(KERN_INFO "Buffer allocation failed\n"); 272 return -ENOMEM; 273 } 274 if (s->buf_change) { 275 ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE); 276 if (ret < 0) 277 return ret; 278 } 279 comedi_alloc_subdevice_minor(dev, s); 280 } 281 282 if (!s->range_table && !s->range_table_list) 283 s->range_table = &range_unknown; 284 285 if (!s->insn_read && s->insn_bits) 286 s->insn_read = insn_rw_emulate_bits; 287 if (!s->insn_write && s->insn_bits) 288 s->insn_write = insn_rw_emulate_bits; 289 290 if (!s->insn_read) 291 s->insn_read = insn_inval; 292 if (!s->insn_write) 293 s->insn_write = insn_inval; 294 if (!s->insn_bits) 295 s->insn_bits = insn_inval; 296 if (!s->insn_config) 297 s->insn_config = insn_inval; 298 299 if (!s->poll) 300 s->poll = poll_invalid; 301 } 302 303 return 0; 304} 305 306/* generic recognize function for drivers 307 * that register their supported board names */ 308static void *comedi_recognize(struct comedi_driver *driv, const char *name) 309{ 310 unsigned i; 311 const char *const *name_ptr = driv->board_name; 312 for (i = 0; i < driv->num_names; i++) { 313 if (strcmp(*name_ptr, name) == 0) 314 return (void *)name_ptr; 315 name_ptr = 316 (const char *const *)((const char *)name_ptr + 317 driv->offset); 318 } 319 320 return NULL; 321} 322 323static void comedi_report_boards(struct comedi_driver *driv) 324{ 325 unsigned int i; 326 const char *const *name_ptr; 327 328 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 329 driv->driver_name); 330 331 name_ptr = driv->board_name; 332 for (i = 0; i < driv->num_names; i++) { 333 printk(KERN_INFO " %s\n", *name_ptr); 334 name_ptr = (const char **)((char *)name_ptr + driv->offset); 335 } 336 337 if (driv->num_names == 0) 338 printk(KERN_INFO " %s\n", driv->driver_name); 339} 340 341static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 342{ 343 return -EINVAL; 344} 345 346int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 347 struct comedi_insn *insn, unsigned int *data) 348{ 349 return -EINVAL; 350} 351 352static int insn_rw_emulate_bits(struct comedi_device *dev, 353 struct comedi_subdevice *s, 354 struct comedi_insn *insn, unsigned int *data) 355{ 356 struct comedi_insn new_insn; 357 int ret; 358 static const unsigned channels_per_bitfield = 32; 359 360 unsigned chan = CR_CHAN(insn->chanspec); 361 const unsigned base_bitfield_channel = 362 (chan < channels_per_bitfield) ? 0 : chan; 363 unsigned int new_data[2]; 364 memset(new_data, 0, sizeof(new_data)); 365 memset(&new_insn, 0, sizeof(new_insn)); 366 new_insn.insn = INSN_BITS; 367 new_insn.chanspec = base_bitfield_channel; 368 new_insn.n = 2; 369 new_insn.data = new_data; 370 new_insn.subdev = insn->subdev; 371 372 if (insn->insn == INSN_WRITE) { 373 if (!(s->subdev_flags & SDF_WRITABLE)) 374 return -EINVAL; 375 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 376 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 377 : 0; /* bits */ 378 } 379 380 ret = s->insn_bits(dev, s, &new_insn, new_data); 381 if (ret < 0) 382 return ret; 383 384 if (insn->insn == INSN_READ) 385 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 386 387 return 1; 388} 389 390static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr) 391{ 392 unsigned long ret = 0UL; 393 pmd_t *pmd; 394 pte_t *ptep, pte; 395 pud_t *pud; 396 397 if (!pgd_none(*pgd)) { 398 pud = pud_offset(pgd, adr); 399 pmd = pmd_offset(pud, adr); 400 if (!pmd_none(*pmd)) { 401 ptep = pte_offset_kernel(pmd, adr); 402 pte = *ptep; 403 if (pte_present(pte)) { 404 ret = (unsigned long) 405 page_address(pte_page(pte)); 406 ret |= (adr & (PAGE_SIZE - 1)); 407 } 408 } 409 } 410 return ret; 411} 412 413static inline unsigned long kvirt_to_kva(unsigned long adr) 414{ 415 unsigned long va, kva; 416 417 va = adr; 418 kva = uvirt_to_kva(pgd_offset_k(va), va); 419 420 return kva; 421} 422 423int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 424 unsigned long new_size) 425{ 426 struct comedi_async *async = s->async; 427 428 /* Round up new_size to multiple of PAGE_SIZE */ 429 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 430 431 /* if no change is required, do nothing */ 432 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 433 return 0; 434 435 /* deallocate old buffer */ 436 if (async->prealloc_buf) { 437 vunmap(async->prealloc_buf); 438 async->prealloc_buf = NULL; 439 async->prealloc_bufsz = 0; 440 } 441 if (async->buf_page_list) { 442 unsigned i; 443 for (i = 0; i < async->n_buf_pages; ++i) { 444 if (async->buf_page_list[i].virt_addr) { 445 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 446 if (s->async_dma_dir != DMA_NONE) { 447 dma_free_coherent(dev->hw_dev, 448 PAGE_SIZE, 449 async-> 450 buf_page_list 451 [i].virt_addr, 452 async-> 453 buf_page_list 454 [i].dma_addr); 455 } else { 456 free_page((unsigned long) 457 async->buf_page_list[i]. 458 virt_addr); 459 } 460 } 461 } 462 vfree(async->buf_page_list); 463 async->buf_page_list = NULL; 464 async->n_buf_pages = 0; 465 } 466 /* allocate new buffer */ 467 if (new_size) { 468 unsigned i = 0; 469 unsigned n_pages = new_size >> PAGE_SHIFT; 470 struct page **pages = NULL; 471 472 async->buf_page_list = 473 vmalloc(sizeof(struct comedi_buf_page) * n_pages); 474 if (async->buf_page_list) { 475 memset(async->buf_page_list, 0, 476 sizeof(struct comedi_buf_page) * n_pages); 477 pages = vmalloc(sizeof(struct page *) * n_pages); 478 } 479 if (pages) { 480 for (i = 0; i < n_pages; i++) { 481 if (s->async_dma_dir != DMA_NONE) { 482 async->buf_page_list[i].virt_addr = 483 dma_alloc_coherent(dev->hw_dev, 484 PAGE_SIZE, 485 &async-> 486 buf_page_list 487 [i].dma_addr, 488 GFP_KERNEL | 489 __GFP_COMP); 490 } else { 491 async->buf_page_list[i].virt_addr = 492 (void *) 493 get_zeroed_page(GFP_KERNEL); 494 } 495 if (async->buf_page_list[i].virt_addr == NULL) 496 break; 497 498 set_bit(PG_reserved, 499 &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 500 pages[i] = virt_to_page(async->buf_page_list[i].virt_addr); 501 } 502 } 503 if (i == n_pages) { 504 async->prealloc_buf = 505 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 506 } 507 vfree(pages); 508 509 if (async->prealloc_buf == NULL) { 510 /* Some allocation failed above. */ 511 if (async->buf_page_list) { 512 for (i = 0; i < n_pages; i++) { 513 if (async->buf_page_list[i].virt_addr == 514 NULL) { 515 break; 516 } 517 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 518 if (s->async_dma_dir != DMA_NONE) { 519 dma_free_coherent(dev->hw_dev, 520 PAGE_SIZE, 521 async-> 522 buf_page_list 523 [i].virt_addr, 524 async-> 525 buf_page_list 526 [i].dma_addr); 527 } else { 528 free_page((unsigned long) 529 async->buf_page_list 530 [i].virt_addr); 531 } 532 } 533 vfree(async->buf_page_list); 534 async->buf_page_list = NULL; 535 } 536 return -ENOMEM; 537 } 538 async->n_buf_pages = n_pages; 539 } 540 async->prealloc_bufsz = new_size; 541 542 return 0; 543} 544 545/* munging is applied to data by core as it passes between user 546 * and kernel space */ 547static unsigned int comedi_buf_munge(struct comedi_async *async, 548 unsigned int num_bytes) 549{ 550 struct comedi_subdevice *s = async->subdevice; 551 unsigned int count = 0; 552 const unsigned num_sample_bytes = bytes_per_sample(s); 553 554 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 555 async->munge_count += num_bytes; 556 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 557 return num_bytes; 558 } 559 /* don't munge partial samples */ 560 num_bytes -= num_bytes % num_sample_bytes; 561 while (count < num_bytes) { 562 int block_size; 563 564 block_size = num_bytes - count; 565 if (block_size < 0) { 566 printk(KERN_WARNING 567 "%s: %s: bug! block_size is negative\n", 568 __FILE__, __func__); 569 break; 570 } 571 if ((int)(async->munge_ptr + block_size - 572 async->prealloc_bufsz) > 0) 573 block_size = async->prealloc_bufsz - async->munge_ptr; 574 575 s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, 576 block_size, async->munge_chan); 577 578 smp_wmb(); /* barrier insures data is munged in buffer 579 * before munge_count is incremented */ 580 581 async->munge_chan += block_size / num_sample_bytes; 582 async->munge_chan %= async->cmd.chanlist_len; 583 async->munge_count += block_size; 584 async->munge_ptr += block_size; 585 async->munge_ptr %= async->prealloc_bufsz; 586 count += block_size; 587 } 588 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 589 return count; 590} 591 592unsigned int comedi_buf_write_n_available(struct comedi_async *async) 593{ 594 unsigned int free_end; 595 unsigned int nbytes; 596 597 if (async == NULL) 598 return 0; 599 600 free_end = async->buf_read_count + async->prealloc_bufsz; 601 nbytes = free_end - async->buf_write_alloc_count; 602 nbytes -= nbytes % bytes_per_sample(async->subdevice); 603 /* barrier insures the read of buf_read_count in this 604 query occurs before any following writes to the buffer which 605 might be based on the return value from this query. 606 */ 607 smp_mb(); 608 return nbytes; 609} 610 611/* allocates chunk for the writer from free buffer space */ 612unsigned int comedi_buf_write_alloc(struct comedi_async *async, 613 unsigned int nbytes) 614{ 615 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 616 617 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 618 nbytes = free_end - async->buf_write_alloc_count; 619 620 async->buf_write_alloc_count += nbytes; 621 /* barrier insures the read of buf_read_count above occurs before 622 we write data to the write-alloc'ed buffer space */ 623 smp_mb(); 624 return nbytes; 625} 626EXPORT_SYMBOL(comedi_buf_write_alloc); 627 628/* allocates nothing unless it can completely fulfill the request */ 629unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, 630 unsigned int nbytes) 631{ 632 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 633 634 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 635 nbytes = 0; 636 637 async->buf_write_alloc_count += nbytes; 638 /* barrier insures the read of buf_read_count above occurs before 639 we write data to the write-alloc'ed buffer space */ 640 smp_mb(); 641 return nbytes; 642} 643 644/* transfers a chunk from writer to filled buffer space */ 645unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) 646{ 647 if ((int)(async->buf_write_count + nbytes - 648 async->buf_write_alloc_count) > 0) { 649 printk 650 (KERN_INFO "comedi: attempted to write-free more bytes than have been write-allocated.\n"); 651 nbytes = async->buf_write_alloc_count - async->buf_write_count; 652 } 653 async->buf_write_count += nbytes; 654 async->buf_write_ptr += nbytes; 655 comedi_buf_munge(async, async->buf_write_count - async->munge_count); 656 if (async->buf_write_ptr >= async->prealloc_bufsz) 657 async->buf_write_ptr %= async->prealloc_bufsz; 658 659 return nbytes; 660} 661EXPORT_SYMBOL(comedi_buf_write_free); 662 663/* allocates a chunk for the reader from filled (and munged) buffer space */ 664unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) 665{ 666 if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > 667 0) { 668 nbytes = async->munge_count - async->buf_read_alloc_count; 669 } 670 async->buf_read_alloc_count += nbytes; 671 /* barrier insures read of munge_count occurs before we actually read 672 data out of buffer */ 673 smp_rmb(); 674 return nbytes; 675} 676EXPORT_SYMBOL(comedi_buf_read_alloc); 677 678/* transfers control of a chunk from reader to free buffer space */ 679unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) 680{ 681 /* barrier insures data has been read out of 682 * buffer before read count is incremented */ 683 smp_mb(); 684 if ((int)(async->buf_read_count + nbytes - 685 async->buf_read_alloc_count) > 0) { 686 printk(KERN_INFO 687 "comedi: attempted to read-free more bytes than have been read-allocated.\n"); 688 nbytes = async->buf_read_alloc_count - async->buf_read_count; 689 } 690 async->buf_read_count += nbytes; 691 async->buf_read_ptr += nbytes; 692 async->buf_read_ptr %= async->prealloc_bufsz; 693 return nbytes; 694} 695EXPORT_SYMBOL(comedi_buf_read_free); 696 697void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, 698 const void *data, unsigned int num_bytes) 699{ 700 unsigned int write_ptr = async->buf_write_ptr + offset; 701 702 if (write_ptr >= async->prealloc_bufsz) 703 write_ptr %= async->prealloc_bufsz; 704 705 while (num_bytes) { 706 unsigned int block_size; 707 708 if (write_ptr + num_bytes > async->prealloc_bufsz) 709 block_size = async->prealloc_bufsz - write_ptr; 710 else 711 block_size = num_bytes; 712 713 memcpy(async->prealloc_buf + write_ptr, data, block_size); 714 715 data += block_size; 716 num_bytes -= block_size; 717 718 write_ptr = 0; 719 } 720} 721EXPORT_SYMBOL(comedi_buf_memcpy_to); 722 723void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, 724 void *dest, unsigned int nbytes) 725{ 726 void *src; 727 unsigned int read_ptr = async->buf_read_ptr + offset; 728 729 if (read_ptr >= async->prealloc_bufsz) 730 read_ptr %= async->prealloc_bufsz; 731 732 while (nbytes) { 733 unsigned int block_size; 734 735 src = async->prealloc_buf + read_ptr; 736 737 if (nbytes >= async->prealloc_bufsz - read_ptr) 738 block_size = async->prealloc_bufsz - read_ptr; 739 else 740 block_size = nbytes; 741 742 memcpy(dest, src, block_size); 743 nbytes -= block_size; 744 dest += block_size; 745 read_ptr = 0; 746 } 747} 748EXPORT_SYMBOL(comedi_buf_memcpy_from); 749 750unsigned int comedi_buf_read_n_available(struct comedi_async *async) 751{ 752 unsigned num_bytes; 753 754 if (async == NULL) 755 return 0; 756 num_bytes = async->munge_count - async->buf_read_count; 757 /* barrier insures the read of munge_count in this 758 query occurs before any following reads of the buffer which 759 might be based on the return value from this query. 760 */ 761 smp_rmb(); 762 return num_bytes; 763} 764EXPORT_SYMBOL(comedi_buf_read_n_available); 765 766int comedi_buf_get(struct comedi_async *async, short *x) 767{ 768 unsigned int n = comedi_buf_read_n_available(async); 769 770 if (n < sizeof(short)) 771 return 0; 772 comedi_buf_read_alloc(async, sizeof(short)); 773 *x = *(short *)(async->prealloc_buf + async->buf_read_ptr); 774 comedi_buf_read_free(async, sizeof(short)); 775 return 1; 776} 777EXPORT_SYMBOL(comedi_buf_get); 778 779int comedi_buf_put(struct comedi_async *async, short x) 780{ 781 unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); 782 783 if (n < sizeof(short)) { 784 async->events |= COMEDI_CB_ERROR; 785 return 0; 786 } 787 *(short *)(async->prealloc_buf + async->buf_write_ptr) = x; 788 comedi_buf_write_free(async, sizeof(short)); 789 return 1; 790} 791EXPORT_SYMBOL(comedi_buf_put); 792 793void comedi_reset_async_buf(struct comedi_async *async) 794{ 795 async->buf_write_alloc_count = 0; 796 async->buf_write_count = 0; 797 async->buf_read_alloc_count = 0; 798 async->buf_read_count = 0; 799 800 async->buf_write_ptr = 0; 801 async->buf_read_ptr = 0; 802 803 async->cur_chan = 0; 804 async->scan_progress = 0; 805 async->munge_chan = 0; 806 async->munge_count = 0; 807 async->munge_ptr = 0; 808 809 async->events = 0; 810} 811 812static int comedi_auto_config(struct device *hardware_device, 813 const char *board_name, const int *options, 814 unsigned num_options) 815{ 816 struct comedi_devconfig it; 817 int minor; 818 struct comedi_device_file_info *dev_file_info; 819 int retval; 820 unsigned *private_data = NULL; 821 822 if (!comedi_autoconfig) { 823 dev_set_drvdata(hardware_device, NULL); 824 return 0; 825 } 826 827 minor = comedi_alloc_board_minor(hardware_device); 828 if (minor < 0) 829 return minor; 830 831 private_data = kmalloc(sizeof(unsigned), GFP_KERNEL); 832 if (private_data == NULL) { 833 retval = -ENOMEM; 834 goto cleanup; 835 } 836 *private_data = minor; 837 dev_set_drvdata(hardware_device, private_data); 838 839 dev_file_info = comedi_get_device_file_info(minor); 840 841 memset(&it, 0, sizeof(it)); 842 strncpy(it.board_name, board_name, COMEDI_NAMELEN); 843 it.board_name[COMEDI_NAMELEN - 1] = '\0'; 844 BUG_ON(num_options > COMEDI_NDEVCONFOPTS); 845 memcpy(it.options, options, num_options * sizeof(int)); 846 847 mutex_lock(&dev_file_info->device->mutex); 848 retval = comedi_device_attach(dev_file_info->device, &it); 849 mutex_unlock(&dev_file_info->device->mutex); 850 851cleanup: 852 if (retval < 0) { 853 kfree(private_data); 854 comedi_free_board_minor(minor); 855 } 856 return retval; 857} 858 859static void comedi_auto_unconfig(struct device *hardware_device) 860{ 861 unsigned *minor = (unsigned *)dev_get_drvdata(hardware_device); 862 if (minor == NULL) 863 return; 864 865 BUG_ON(*minor >= COMEDI_NUM_BOARD_MINORS); 866 867 comedi_free_board_minor(*minor); 868 dev_set_drvdata(hardware_device, NULL); 869 kfree(minor); 870} 871 872int comedi_pci_auto_config(struct pci_dev *pcidev, const char *board_name) 873{ 874 int options[2]; 875 876 /* pci bus */ 877 options[0] = pcidev->bus->number; 878 /* pci slot */ 879 options[1] = PCI_SLOT(pcidev->devfn); 880 881 return comedi_auto_config(&pcidev->dev, board_name, 882 options, ARRAY_SIZE(options)); 883} 884EXPORT_SYMBOL_GPL(comedi_pci_auto_config); 885 886void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 887{ 888 comedi_auto_unconfig(&pcidev->dev); 889} 890EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); 891 892int comedi_usb_auto_config(struct usb_device *usbdev, const char *board_name) 893{ 894 BUG_ON(usbdev == NULL); 895 return comedi_auto_config(&usbdev->dev, board_name, NULL, 0); 896} 897EXPORT_SYMBOL_GPL(comedi_usb_auto_config); 898 899void comedi_usb_auto_unconfig(struct usb_device *usbdev) 900{ 901 BUG_ON(usbdev == NULL); 902 comedi_auto_unconfig(&usbdev->dev); 903} 904EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig); 905