drivers.c revision 3ad4e219606fa317f778b26553889520aed7925c
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(KERN_INFO "comedi: failed to increment module count, skipping\n"); 121 continue; 122 } 123 if (driv->num_names) { 124 dev->board_ptr = comedi_recognize(driv, it->board_name); 125 if (dev->board_ptr == NULL) { 126 module_put(driv->module); 127 continue; 128 } 129 } else { 130 if (strcmp(driv->driver_name, it->board_name)) { 131 module_put(driv->module); 132 continue; 133 } 134 } 135 /* initialize dev->driver here so 136 * comedi_error() can be called from attach */ 137 dev->driver = driv; 138 ret = driv->attach(dev, it); 139 if (ret < 0) { 140 module_put(dev->driver->module); 141 __comedi_device_detach(dev); 142 return ret; 143 } 144 goto attached; 145 } 146 147 /* recognize has failed if we get here */ 148 /* report valid board names before returning error */ 149 for (driv = comedi_drivers; driv; driv = driv->next) { 150 if (!try_module_get(driv->module)) { 151 printk(KERN_INFO 152 "comedi: failed to increment module count\n"); 153 continue; 154 } 155 comedi_report_boards(driv); 156 module_put(driv->module); 157 } 158 return -EIO; 159 160attached: 161 /* do a little post-config cleanup */ 162 ret = postconfig(dev); 163 module_put(dev->driver->module); 164 if (ret < 0) { 165 __comedi_device_detach(dev); 166 return ret; 167 } 168 169 if (!dev->board_name) { 170 printk(KERN_WARNING "BUG: dev->board_name=<%p>\n", 171 dev->board_name); 172 dev->board_name = "BUG"; 173 } 174 smp_wmb(); 175 dev->attached = 1; 176 177 return 0; 178} 179 180int comedi_driver_register(struct comedi_driver *driver) 181{ 182 driver->next = comedi_drivers; 183 comedi_drivers = driver; 184 185 return 0; 186} 187EXPORT_SYMBOL(comedi_driver_register); 188 189int comedi_driver_unregister(struct comedi_driver *driver) 190{ 191 struct comedi_driver *prev; 192 int i; 193 194 /* check for devices using this driver */ 195 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 196 struct comedi_device_file_info *dev_file_info = 197 comedi_get_device_file_info(i); 198 struct comedi_device *dev; 199 200 if (dev_file_info == NULL) 201 continue; 202 dev = dev_file_info->device; 203 204 mutex_lock(&dev->mutex); 205 if (dev->attached && dev->driver == driver) { 206 if (dev->use_count) 207 printk(KERN_WARNING "BUG! detaching device with use_count=%d\n", 208 dev->use_count); 209 comedi_device_detach(dev); 210 } 211 mutex_unlock(&dev->mutex); 212 } 213 214 if (comedi_drivers == driver) { 215 comedi_drivers = driver->next; 216 return 0; 217 } 218 219 for (prev = comedi_drivers; prev->next; prev = prev->next) { 220 if (prev->next == driver) { 221 prev->next = driver->next; 222 return 0; 223 } 224 } 225 return -EINVAL; 226} 227EXPORT_SYMBOL(comedi_driver_unregister); 228 229static int postconfig(struct comedi_device *dev) 230{ 231 int i; 232 struct comedi_subdevice *s; 233 struct comedi_async *async = NULL; 234 int ret; 235 236 for (i = 0; i < dev->n_subdevices; i++) { 237 s = dev->subdevices + i; 238 239 if (s->type == COMEDI_SUBD_UNUSED) 240 continue; 241 242 if (s->len_chanlist == 0) 243 s->len_chanlist = 1; 244 245 if (s->do_cmd) { 246 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 247 SDF_CMD_WRITE)) == 0); 248 BUG_ON(!s->do_cmdtest); 249 250 async = 251 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 252 if (async == NULL) { 253 printk(KERN_INFO 254 "failed to allocate async struct\n"); 255 return -ENOMEM; 256 } 257 init_waitqueue_head(&async->wait_head); 258 async->subdevice = s; 259 s->async = async; 260 261#define DEFAULT_BUF_MAXSIZE (64*1024) 262#define DEFAULT_BUF_SIZE (64*1024) 263 264 async->max_bufsize = DEFAULT_BUF_MAXSIZE; 265 266 async->prealloc_buf = NULL; 267 async->prealloc_bufsz = 0; 268 if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) { 269 printk(KERN_INFO "Buffer allocation failed\n"); 270 return -ENOMEM; 271 } 272 if (s->buf_change) { 273 ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE); 274 if (ret < 0) 275 return ret; 276 } 277 comedi_alloc_subdevice_minor(dev, s); 278 } 279 280 if (!s->range_table && !s->range_table_list) 281 s->range_table = &range_unknown; 282 283 if (!s->insn_read && s->insn_bits) 284 s->insn_read = insn_rw_emulate_bits; 285 if (!s->insn_write && s->insn_bits) 286 s->insn_write = insn_rw_emulate_bits; 287 288 if (!s->insn_read) 289 s->insn_read = insn_inval; 290 if (!s->insn_write) 291 s->insn_write = insn_inval; 292 if (!s->insn_bits) 293 s->insn_bits = insn_inval; 294 if (!s->insn_config) 295 s->insn_config = insn_inval; 296 297 if (!s->poll) 298 s->poll = poll_invalid; 299 } 300 301 return 0; 302} 303 304/* generic recognize function for drivers 305 * that register their supported board names */ 306static void *comedi_recognize(struct comedi_driver *driv, const char *name) 307{ 308 unsigned i; 309 const char *const *name_ptr = driv->board_name; 310 for (i = 0; i < driv->num_names; i++) { 311 if (strcmp(*name_ptr, name) == 0) 312 return (void *)name_ptr; 313 name_ptr = 314 (const char *const *)((const char *)name_ptr + 315 driv->offset); 316 } 317 318 return NULL; 319} 320 321static void comedi_report_boards(struct comedi_driver *driv) 322{ 323 unsigned int i; 324 const char *const *name_ptr; 325 326 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 327 driv->driver_name); 328 329 name_ptr = driv->board_name; 330 for (i = 0; i < driv->num_names; i++) { 331 printk(KERN_INFO " %s\n", *name_ptr); 332 name_ptr = (const char **)((char *)name_ptr + driv->offset); 333 } 334 335 if (driv->num_names == 0) 336 printk(KERN_INFO " %s\n", driv->driver_name); 337} 338 339static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 340{ 341 return -EINVAL; 342} 343 344int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 345 struct comedi_insn *insn, unsigned int *data) 346{ 347 return -EINVAL; 348} 349 350static int insn_rw_emulate_bits(struct comedi_device *dev, 351 struct comedi_subdevice *s, 352 struct comedi_insn *insn, unsigned int *data) 353{ 354 struct comedi_insn new_insn; 355 int ret; 356 static const unsigned channels_per_bitfield = 32; 357 358 unsigned chan = CR_CHAN(insn->chanspec); 359 const unsigned base_bitfield_channel = 360 (chan < channels_per_bitfield) ? 0 : chan; 361 unsigned int new_data[2]; 362 memset(new_data, 0, sizeof(new_data)); 363 memset(&new_insn, 0, sizeof(new_insn)); 364 new_insn.insn = INSN_BITS; 365 new_insn.chanspec = base_bitfield_channel; 366 new_insn.n = 2; 367 new_insn.data = new_data; 368 new_insn.subdev = insn->subdev; 369 370 if (insn->insn == INSN_WRITE) { 371 if (!(s->subdev_flags & SDF_WRITABLE)) 372 return -EINVAL; 373 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 374 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 375 : 0; /* bits */ 376 } 377 378 ret = s->insn_bits(dev, s, &new_insn, new_data); 379 if (ret < 0) 380 return ret; 381 382 if (insn->insn == INSN_READ) 383 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 384 385 return 1; 386} 387 388static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr) 389{ 390 unsigned long ret = 0UL; 391 pmd_t *pmd; 392 pte_t *ptep, pte; 393 pud_t *pud; 394 395 if (!pgd_none(*pgd)) { 396 pud = pud_offset(pgd, adr); 397 pmd = pmd_offset(pud, adr); 398 if (!pmd_none(*pmd)) { 399 ptep = pte_offset_kernel(pmd, adr); 400 pte = *ptep; 401 if (pte_present(pte)) { 402 ret = (unsigned long) 403 page_address(pte_page(pte)); 404 ret |= (adr & (PAGE_SIZE - 1)); 405 } 406 } 407 } 408 return ret; 409} 410 411static inline unsigned long kvirt_to_kva(unsigned long adr) 412{ 413 unsigned long va, kva; 414 415 va = adr; 416 kva = uvirt_to_kva(pgd_offset_k(va), va); 417 418 return kva; 419} 420 421int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 422 unsigned long new_size) 423{ 424 struct comedi_async *async = s->async; 425 426 /* Round up new_size to multiple of PAGE_SIZE */ 427 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 428 429 /* if no change is required, do nothing */ 430 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 431 return 0; 432 433 /* deallocate old buffer */ 434 if (async->prealloc_buf) { 435 vunmap(async->prealloc_buf); 436 async->prealloc_buf = NULL; 437 async->prealloc_bufsz = 0; 438 } 439 if (async->buf_page_list) { 440 unsigned i; 441 for (i = 0; i < async->n_buf_pages; ++i) { 442 if (async->buf_page_list[i].virt_addr) { 443 clear_bit(PG_reserved, 444 &(virt_to_page(async->buf_page_list[i]. 445 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 vzalloc(sizeof(struct comedi_buf_page) * n_pages); 474 if (async->buf_page_list) 475 pages = vmalloc(sizeof(struct page *) * n_pages); 476 477 if (pages) { 478 for (i = 0; i < n_pages; i++) { 479 if (s->async_dma_dir != DMA_NONE) { 480 async->buf_page_list[i].virt_addr = 481 dma_alloc_coherent(dev->hw_dev, 482 PAGE_SIZE, 483 &async-> 484 buf_page_list 485 [i].dma_addr, 486 GFP_KERNEL | 487 __GFP_COMP); 488 } else { 489 async->buf_page_list[i].virt_addr = 490 (void *) 491 get_zeroed_page(GFP_KERNEL); 492 } 493 if (async->buf_page_list[i].virt_addr == NULL) 494 break; 495 496 set_bit(PG_reserved, 497 &(virt_to_page(async->buf_page_list[i]. 498 virt_addr)->flags)); 499 pages[i] = virt_to_page(async->buf_page_list[i]. 500 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, 518 &(virt_to_page(async-> 519 buf_page_list[i]. 520 virt_addr)->flags)); 521 if (s->async_dma_dir != DMA_NONE) { 522 dma_free_coherent(dev->hw_dev, 523 PAGE_SIZE, 524 async-> 525 buf_page_list 526 [i].virt_addr, 527 async-> 528 buf_page_list 529 [i].dma_addr); 530 } else { 531 free_page((unsigned long) 532 async->buf_page_list 533 [i].virt_addr); 534 } 535 } 536 vfree(async->buf_page_list); 537 async->buf_page_list = NULL; 538 } 539 return -ENOMEM; 540 } 541 async->n_buf_pages = n_pages; 542 } 543 async->prealloc_bufsz = new_size; 544 545 return 0; 546} 547 548/* munging is applied to data by core as it passes between user 549 * and kernel space */ 550static unsigned int comedi_buf_munge(struct comedi_async *async, 551 unsigned int num_bytes) 552{ 553 struct comedi_subdevice *s = async->subdevice; 554 unsigned int count = 0; 555 const unsigned num_sample_bytes = bytes_per_sample(s); 556 557 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 558 async->munge_count += num_bytes; 559 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 560 return num_bytes; 561 } 562 /* don't munge partial samples */ 563 num_bytes -= num_bytes % num_sample_bytes; 564 while (count < num_bytes) { 565 int block_size; 566 567 block_size = num_bytes - count; 568 if (block_size < 0) { 569 printk(KERN_WARNING 570 "%s: %s: bug! block_size is negative\n", 571 __FILE__, __func__); 572 break; 573 } 574 if ((int)(async->munge_ptr + block_size - 575 async->prealloc_bufsz) > 0) 576 block_size = async->prealloc_bufsz - async->munge_ptr; 577 578 s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, 579 block_size, async->munge_chan); 580 581 smp_wmb(); /* barrier insures data is munged in buffer 582 * before munge_count is incremented */ 583 584 async->munge_chan += block_size / num_sample_bytes; 585 async->munge_chan %= async->cmd.chanlist_len; 586 async->munge_count += block_size; 587 async->munge_ptr += block_size; 588 async->munge_ptr %= async->prealloc_bufsz; 589 count += block_size; 590 } 591 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 592 return count; 593} 594 595unsigned int comedi_buf_write_n_available(struct comedi_async *async) 596{ 597 unsigned int free_end; 598 unsigned int nbytes; 599 600 if (async == NULL) 601 return 0; 602 603 free_end = async->buf_read_count + async->prealloc_bufsz; 604 nbytes = free_end - async->buf_write_alloc_count; 605 nbytes -= nbytes % bytes_per_sample(async->subdevice); 606 /* barrier insures the read of buf_read_count in this 607 query occurs before any following writes to the buffer which 608 might be based on the return value from this query. 609 */ 610 smp_mb(); 611 return nbytes; 612} 613 614/* allocates chunk for the writer from free buffer space */ 615unsigned int comedi_buf_write_alloc(struct comedi_async *async, 616 unsigned int nbytes) 617{ 618 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 619 620 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 621 nbytes = free_end - async->buf_write_alloc_count; 622 623 async->buf_write_alloc_count += nbytes; 624 /* barrier insures the read of buf_read_count above occurs before 625 we write data to the write-alloc'ed buffer space */ 626 smp_mb(); 627 return nbytes; 628} 629EXPORT_SYMBOL(comedi_buf_write_alloc); 630 631/* allocates nothing unless it can completely fulfill the request */ 632unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, 633 unsigned int nbytes) 634{ 635 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 636 637 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 638 nbytes = 0; 639 640 async->buf_write_alloc_count += nbytes; 641 /* barrier insures the read of buf_read_count above occurs before 642 we write data to the write-alloc'ed buffer space */ 643 smp_mb(); 644 return nbytes; 645} 646 647/* transfers a chunk from writer to filled buffer space */ 648unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) 649{ 650 if ((int)(async->buf_write_count + nbytes - 651 async->buf_write_alloc_count) > 0) { 652 printk(KERN_INFO "comedi: attempted to write-free more bytes than have been write-allocated.\n"); 653 nbytes = async->buf_write_alloc_count - async->buf_write_count; 654 } 655 async->buf_write_count += nbytes; 656 async->buf_write_ptr += nbytes; 657 comedi_buf_munge(async, async->buf_write_count - async->munge_count); 658 if (async->buf_write_ptr >= async->prealloc_bufsz) 659 async->buf_write_ptr %= async->prealloc_bufsz; 660 661 return nbytes; 662} 663EXPORT_SYMBOL(comedi_buf_write_free); 664 665/* allocates a chunk for the reader from filled (and munged) buffer space */ 666unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) 667{ 668 if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > 669 0) { 670 nbytes = async->munge_count - async->buf_read_alloc_count; 671 } 672 async->buf_read_alloc_count += nbytes; 673 /* barrier insures read of munge_count occurs before we actually read 674 data out of buffer */ 675 smp_rmb(); 676 return nbytes; 677} 678EXPORT_SYMBOL(comedi_buf_read_alloc); 679 680/* transfers control of a chunk from reader to free buffer space */ 681unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) 682{ 683 /* barrier insures data has been read out of 684 * buffer before read count is incremented */ 685 smp_mb(); 686 if ((int)(async->buf_read_count + nbytes - 687 async->buf_read_alloc_count) > 0) { 688 printk(KERN_INFO 689 "comedi: attempted to read-free more bytes than have been read-allocated.\n"); 690 nbytes = async->buf_read_alloc_count - async->buf_read_count; 691 } 692 async->buf_read_count += nbytes; 693 async->buf_read_ptr += nbytes; 694 async->buf_read_ptr %= async->prealloc_bufsz; 695 return nbytes; 696} 697EXPORT_SYMBOL(comedi_buf_read_free); 698 699void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, 700 const void *data, unsigned int num_bytes) 701{ 702 unsigned int write_ptr = async->buf_write_ptr + offset; 703 704 if (write_ptr >= async->prealloc_bufsz) 705 write_ptr %= async->prealloc_bufsz; 706 707 while (num_bytes) { 708 unsigned int block_size; 709 710 if (write_ptr + num_bytes > async->prealloc_bufsz) 711 block_size = async->prealloc_bufsz - write_ptr; 712 else 713 block_size = num_bytes; 714 715 memcpy(async->prealloc_buf + write_ptr, data, block_size); 716 717 data += block_size; 718 num_bytes -= block_size; 719 720 write_ptr = 0; 721 } 722} 723EXPORT_SYMBOL(comedi_buf_memcpy_to); 724 725void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, 726 void *dest, unsigned int nbytes) 727{ 728 void *src; 729 unsigned int read_ptr = async->buf_read_ptr + offset; 730 731 if (read_ptr >= async->prealloc_bufsz) 732 read_ptr %= async->prealloc_bufsz; 733 734 while (nbytes) { 735 unsigned int block_size; 736 737 src = async->prealloc_buf + read_ptr; 738 739 if (nbytes >= async->prealloc_bufsz - read_ptr) 740 block_size = async->prealloc_bufsz - read_ptr; 741 else 742 block_size = nbytes; 743 744 memcpy(dest, src, block_size); 745 nbytes -= block_size; 746 dest += block_size; 747 read_ptr = 0; 748 } 749} 750EXPORT_SYMBOL(comedi_buf_memcpy_from); 751 752unsigned int comedi_buf_read_n_available(struct comedi_async *async) 753{ 754 unsigned num_bytes; 755 756 if (async == NULL) 757 return 0; 758 num_bytes = async->munge_count - async->buf_read_count; 759 /* barrier insures the read of munge_count in this 760 query occurs before any following reads of the buffer which 761 might be based on the return value from this query. 762 */ 763 smp_rmb(); 764 return num_bytes; 765} 766EXPORT_SYMBOL(comedi_buf_read_n_available); 767 768int comedi_buf_get(struct comedi_async *async, short *x) 769{ 770 unsigned int n = comedi_buf_read_n_available(async); 771 772 if (n < sizeof(short)) 773 return 0; 774 comedi_buf_read_alloc(async, sizeof(short)); 775 *x = *(short *)(async->prealloc_buf + async->buf_read_ptr); 776 comedi_buf_read_free(async, sizeof(short)); 777 return 1; 778} 779EXPORT_SYMBOL(comedi_buf_get); 780 781int comedi_buf_put(struct comedi_async *async, short x) 782{ 783 unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); 784 785 if (n < sizeof(short)) { 786 async->events |= COMEDI_CB_ERROR; 787 return 0; 788 } 789 *(short *)(async->prealloc_buf + async->buf_write_ptr) = x; 790 comedi_buf_write_free(async, sizeof(short)); 791 return 1; 792} 793EXPORT_SYMBOL(comedi_buf_put); 794 795void comedi_reset_async_buf(struct comedi_async *async) 796{ 797 async->buf_write_alloc_count = 0; 798 async->buf_write_count = 0; 799 async->buf_read_alloc_count = 0; 800 async->buf_read_count = 0; 801 802 async->buf_write_ptr = 0; 803 async->buf_read_ptr = 0; 804 805 async->cur_chan = 0; 806 async->scan_progress = 0; 807 async->munge_chan = 0; 808 async->munge_count = 0; 809 async->munge_ptr = 0; 810 811 async->events = 0; 812} 813 814static int comedi_auto_config(struct device *hardware_device, 815 const char *board_name, const int *options, 816 unsigned num_options) 817{ 818 struct comedi_devconfig it; 819 int minor; 820 struct comedi_device_file_info *dev_file_info; 821 int retval; 822 unsigned *private_data = NULL; 823 824 if (!comedi_autoconfig) { 825 dev_set_drvdata(hardware_device, NULL); 826 return 0; 827 } 828 829 minor = comedi_alloc_board_minor(hardware_device); 830 if (minor < 0) 831 return minor; 832 833 private_data = kmalloc(sizeof(unsigned), GFP_KERNEL); 834 if (private_data == NULL) { 835 retval = -ENOMEM; 836 goto cleanup; 837 } 838 *private_data = minor; 839 dev_set_drvdata(hardware_device, private_data); 840 841 dev_file_info = comedi_get_device_file_info(minor); 842 843 memset(&it, 0, sizeof(it)); 844 strncpy(it.board_name, board_name, COMEDI_NAMELEN); 845 it.board_name[COMEDI_NAMELEN - 1] = '\0'; 846 BUG_ON(num_options > COMEDI_NDEVCONFOPTS); 847 memcpy(it.options, options, num_options * sizeof(int)); 848 849 mutex_lock(&dev_file_info->device->mutex); 850 retval = comedi_device_attach(dev_file_info->device, &it); 851 mutex_unlock(&dev_file_info->device->mutex); 852 853cleanup: 854 if (retval < 0) { 855 kfree(private_data); 856 comedi_free_board_minor(minor); 857 } 858 return retval; 859} 860 861static void comedi_auto_unconfig(struct device *hardware_device) 862{ 863 unsigned *minor = (unsigned *)dev_get_drvdata(hardware_device); 864 if (minor == NULL) 865 return; 866 867 BUG_ON(*minor >= COMEDI_NUM_BOARD_MINORS); 868 869 comedi_free_board_minor(*minor); 870 dev_set_drvdata(hardware_device, NULL); 871 kfree(minor); 872} 873 874int comedi_pci_auto_config(struct pci_dev *pcidev, const char *board_name) 875{ 876 int options[2]; 877 878 /* pci bus */ 879 options[0] = pcidev->bus->number; 880 /* pci slot */ 881 options[1] = PCI_SLOT(pcidev->devfn); 882 883 return comedi_auto_config(&pcidev->dev, board_name, 884 options, ARRAY_SIZE(options)); 885} 886EXPORT_SYMBOL_GPL(comedi_pci_auto_config); 887 888void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 889{ 890 comedi_auto_unconfig(&pcidev->dev); 891} 892EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); 893 894int comedi_usb_auto_config(struct usb_device *usbdev, const char *board_name) 895{ 896 BUG_ON(usbdev == NULL); 897 return comedi_auto_config(&usbdev->dev, board_name, NULL, 0); 898} 899EXPORT_SYMBOL_GPL(comedi_usb_auto_config); 900 901void comedi_usb_auto_unconfig(struct usb_device *usbdev) 902{ 903 BUG_ON(usbdev == NULL); 904 comedi_auto_unconfig(&usbdev->dev); 905} 906EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig); 907