drivers.c revision 242e7ad91a067243d7ab63b6a25ed2e085733446
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); 57int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 58 unsigned long new_size); 59 60struct comedi_driver *comedi_drivers; 61 62int comedi_modprobe(int minor) 63{ 64 return -EINVAL; 65} 66 67static void cleanup_device(struct comedi_device *dev) 68{ 69 int i; 70 struct comedi_subdevice *s; 71 72 if (dev->subdevices) { 73 for (i = 0; i < dev->n_subdevices; i++) { 74 s = dev->subdevices + i; 75 comedi_free_subdevice_minor(s); 76 if (s->async) { 77 comedi_buf_alloc(dev, s, 0); 78 kfree(s->async); 79 } 80 } 81 kfree(dev->subdevices); 82 dev->subdevices = NULL; 83 dev->n_subdevices = 0; 84 } 85 kfree(dev->private); 86 dev->private = NULL; 87 dev->driver = 0; 88 dev->board_name = NULL; 89 dev->board_ptr = NULL; 90 dev->iobase = 0; 91 dev->irq = 0; 92 dev->read_subdev = NULL; 93 dev->write_subdev = NULL; 94 dev->open = NULL; 95 dev->close = NULL; 96 comedi_set_hw_dev(dev, NULL); 97} 98 99static void __comedi_device_detach(struct comedi_device *dev) 100{ 101 dev->attached = 0; 102 if (dev->driver) 103 dev->driver->detach(dev); 104 else 105 printk(KERN_WARNING "BUG: dev->driver=NULL in comedi_device_detach()\n"); 106 cleanup_device(dev); 107} 108 109void comedi_device_detach(struct comedi_device *dev) 110{ 111 if (!dev->attached) 112 return; 113 __comedi_device_detach(dev); 114} 115 116int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 117{ 118 struct comedi_driver *driv; 119 int ret; 120 121 if (dev->attached) 122 return -EBUSY; 123 124 for (driv = comedi_drivers; driv; driv = driv->next) { 125 if (!try_module_get(driv->module)) { 126 printk 127 (KERN_INFO "comedi: failed to increment module count, skipping\n"); 128 continue; 129 } 130 if (driv->num_names) { 131 dev->board_ptr = comedi_recognize(driv, it->board_name); 132 if (dev->board_ptr == NULL) { 133 module_put(driv->module); 134 continue; 135 } 136 } else { 137 if (strcmp(driv->driver_name, it->board_name)) { 138 module_put(driv->module); 139 continue; 140 } 141 } 142 /* initialize dev->driver here so 143 * comedi_error() can be called from attach */ 144 dev->driver = driv; 145 ret = driv->attach(dev, it); 146 if (ret < 0) { 147 module_put(dev->driver->module); 148 __comedi_device_detach(dev); 149 return ret; 150 } 151 goto attached; 152 } 153 154 /* recognize has failed if we get here */ 155 /* report valid board names before returning error */ 156 for (driv = comedi_drivers; driv; driv = driv->next) { 157 if (!try_module_get(driv->module)) { 158 printk(KERN_INFO "comedi: failed to increment module count\n"); 159 continue; 160 } 161 comedi_report_boards(driv); 162 module_put(driv->module); 163 } 164 return -EIO; 165 166attached: 167 /* do a little post-config cleanup */ 168 ret = postconfig(dev); 169 module_put(dev->driver->module); 170 if (ret < 0) { 171 __comedi_device_detach(dev); 172 return ret; 173 } 174 175 if (!dev->board_name) { 176 printk(KERN_WARNING "BUG: dev->board_name=<%p>\n", 177 dev->board_name); 178 dev->board_name = "BUG"; 179 } 180 smp_wmb(); 181 dev->attached = 1; 182 183 return 0; 184} 185 186int comedi_driver_register(struct comedi_driver *driver) 187{ 188 driver->next = comedi_drivers; 189 comedi_drivers = driver; 190 191 return 0; 192} 193EXPORT_SYMBOL(comedi_driver_register); 194 195int comedi_driver_unregister(struct comedi_driver *driver) 196{ 197 struct comedi_driver *prev; 198 int i; 199 200 /* check for devices using this driver */ 201 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 202 struct comedi_device_file_info *dev_file_info = 203 comedi_get_device_file_info(i); 204 struct comedi_device *dev; 205 206 if (dev_file_info == NULL) 207 continue; 208 dev = dev_file_info->device; 209 210 mutex_lock(&dev->mutex); 211 if (dev->attached && dev->driver == driver) { 212 if (dev->use_count) 213 printk 214 (KERN_WARNING "BUG! detaching device with use_count=%d\n", 215 dev->use_count); 216 comedi_device_detach(dev); 217 } 218 mutex_unlock(&dev->mutex); 219 } 220 221 if (comedi_drivers == driver) { 222 comedi_drivers = driver->next; 223 return 0; 224 } 225 226 for (prev = comedi_drivers; prev->next; prev = prev->next) { 227 if (prev->next == driver) { 228 prev->next = driver->next; 229 return 0; 230 } 231 } 232 return -EINVAL; 233} 234EXPORT_SYMBOL(comedi_driver_unregister); 235 236static int postconfig(struct comedi_device *dev) 237{ 238 int i; 239 struct comedi_subdevice *s; 240 struct comedi_async *async = NULL; 241 int ret; 242 243 for (i = 0; i < dev->n_subdevices; i++) { 244 s = dev->subdevices + i; 245 246 if (s->type == COMEDI_SUBD_UNUSED) 247 continue; 248 249 if (s->len_chanlist == 0) 250 s->len_chanlist = 1; 251 252 if (s->do_cmd) { 253 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 254 SDF_CMD_WRITE)) == 0); 255 BUG_ON(!s->do_cmdtest); 256 257 async = 258 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 259 if (async == NULL) { 260 printk(KERN_INFO "failed to allocate async struct\n"); 261 return -ENOMEM; 262 } 263 init_waitqueue_head(&async->wait_head); 264 async->subdevice = s; 265 s->async = async; 266 267#define DEFAULT_BUF_MAXSIZE (64*1024) 268#define DEFAULT_BUF_SIZE (64*1024) 269 270 async->max_bufsize = DEFAULT_BUF_MAXSIZE; 271 272 async->prealloc_buf = NULL; 273 async->prealloc_bufsz = 0; 274 if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) { 275 printk(KERN_INFO "Buffer allocation failed\n"); 276 return -ENOMEM; 277 } 278 if (s->buf_change) { 279 ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE); 280 if (ret < 0) 281 return ret; 282 } 283 comedi_alloc_subdevice_minor(dev, s); 284 } 285 286 if (!s->range_table && !s->range_table_list) 287 s->range_table = &range_unknown; 288 289 if (!s->insn_read && s->insn_bits) 290 s->insn_read = insn_rw_emulate_bits; 291 if (!s->insn_write && s->insn_bits) 292 s->insn_write = insn_rw_emulate_bits; 293 294 if (!s->insn_read) 295 s->insn_read = insn_inval; 296 if (!s->insn_write) 297 s->insn_write = insn_inval; 298 if (!s->insn_bits) 299 s->insn_bits = insn_inval; 300 if (!s->insn_config) 301 s->insn_config = insn_inval; 302 303 if (!s->poll) 304 s->poll = poll_invalid; 305 } 306 307 return 0; 308} 309 310/* generic recognize function for drivers 311 * that register their supported board names */ 312void *comedi_recognize(struct comedi_driver *driv, const char *name) 313{ 314 unsigned i; 315 const char *const *name_ptr = driv->board_name; 316 for (i = 0; i < driv->num_names; i++) { 317 if (strcmp(*name_ptr, name) == 0) 318 return (void *)name_ptr; 319 name_ptr = 320 (const char *const *)((const char *)name_ptr + 321 driv->offset); 322 } 323 324 return NULL; 325} 326 327void comedi_report_boards(struct comedi_driver *driv) 328{ 329 unsigned int i; 330 const char *const *name_ptr; 331 332 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 333 driv->driver_name); 334 335 name_ptr = driv->board_name; 336 for (i = 0; i < driv->num_names; i++) { 337 printk(KERN_INFO " %s\n", *name_ptr); 338 name_ptr = (const char **)((char *)name_ptr + driv->offset); 339 } 340 341 if (driv->num_names == 0) 342 printk(KERN_INFO " %s\n", driv->driver_name); 343} 344 345static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 346{ 347 return -EINVAL; 348} 349 350int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 351 struct comedi_insn *insn, unsigned int *data) 352{ 353 return -EINVAL; 354} 355 356static int insn_rw_emulate_bits(struct comedi_device *dev, 357 struct comedi_subdevice *s, 358 struct comedi_insn *insn, unsigned int *data) 359{ 360 struct comedi_insn new_insn; 361 int ret; 362 static const unsigned channels_per_bitfield = 32; 363 364 unsigned chan = CR_CHAN(insn->chanspec); 365 const unsigned base_bitfield_channel = 366 (chan < channels_per_bitfield) ? 0 : chan; 367 unsigned int new_data[2]; 368 memset(new_data, 0, sizeof(new_data)); 369 memset(&new_insn, 0, sizeof(new_insn)); 370 new_insn.insn = INSN_BITS; 371 new_insn.chanspec = base_bitfield_channel; 372 new_insn.n = 2; 373 new_insn.data = new_data; 374 new_insn.subdev = insn->subdev; 375 376 if (insn->insn == INSN_WRITE) { 377 if (!(s->subdev_flags & SDF_WRITABLE)) 378 return -EINVAL; 379 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 380 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 381 : 0; /* bits */ 382 } 383 384 ret = s->insn_bits(dev, s, &new_insn, new_data); 385 if (ret < 0) 386 return ret; 387 388 if (insn->insn == INSN_READ) 389 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 390 391 return 1; 392} 393 394static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr) 395{ 396 unsigned long ret = 0UL; 397 pmd_t *pmd; 398 pte_t *ptep, pte; 399 pud_t *pud; 400 401 if (!pgd_none(*pgd)) { 402 pud = pud_offset(pgd, adr); 403 pmd = pmd_offset(pud, adr); 404 if (!pmd_none(*pmd)) { 405 ptep = pte_offset_kernel(pmd, adr); 406 pte = *ptep; 407 if (pte_present(pte)) { 408 ret = (unsigned long) 409 page_address(pte_page(pte)); 410 ret |= (adr & (PAGE_SIZE - 1)); 411 } 412 } 413 } 414 return ret; 415} 416 417static inline unsigned long kvirt_to_kva(unsigned long adr) 418{ 419 unsigned long va, kva; 420 421 va = adr; 422 kva = uvirt_to_kva(pgd_offset_k(va), va); 423 424 return kva; 425} 426 427int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 428 unsigned long new_size) 429{ 430 struct comedi_async *async = s->async; 431 432 /* Round up new_size to multiple of PAGE_SIZE */ 433 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 434 435 /* if no change is required, do nothing */ 436 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 437 return 0; 438 439 /* deallocate old buffer */ 440 if (async->prealloc_buf) { 441 vunmap(async->prealloc_buf); 442 async->prealloc_buf = NULL; 443 async->prealloc_bufsz = 0; 444 } 445 if (async->buf_page_list) { 446 unsigned i; 447 for (i = 0; i < async->n_buf_pages; ++i) { 448 if (async->buf_page_list[i].virt_addr) { 449 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 450 if (s->async_dma_dir != DMA_NONE) { 451 dma_free_coherent(dev->hw_dev, 452 PAGE_SIZE, 453 async-> 454 buf_page_list 455 [i].virt_addr, 456 async-> 457 buf_page_list 458 [i].dma_addr); 459 } else { 460 free_page((unsigned long) 461 async->buf_page_list[i]. 462 virt_addr); 463 } 464 } 465 } 466 vfree(async->buf_page_list); 467 async->buf_page_list = NULL; 468 async->n_buf_pages = 0; 469 } 470 /* allocate new buffer */ 471 if (new_size) { 472 unsigned i = 0; 473 unsigned n_pages = new_size >> PAGE_SHIFT; 474 struct page **pages = NULL; 475 476 async->buf_page_list = 477 vmalloc(sizeof(struct comedi_buf_page) * n_pages); 478 if (async->buf_page_list) { 479 memset(async->buf_page_list, 0, 480 sizeof(struct comedi_buf_page) * n_pages); 481 pages = vmalloc(sizeof(struct page *) * n_pages); 482 } 483 if (pages) { 484 for (i = 0; i < n_pages; i++) { 485 if (s->async_dma_dir != DMA_NONE) { 486 async->buf_page_list[i].virt_addr = 487 dma_alloc_coherent(dev->hw_dev, 488 PAGE_SIZE, 489 &async-> 490 buf_page_list 491 [i].dma_addr, 492 GFP_KERNEL | 493 __GFP_COMP); 494 } else { 495 async->buf_page_list[i].virt_addr = 496 (void *) 497 get_zeroed_page(GFP_KERNEL); 498 } 499 if (async->buf_page_list[i].virt_addr == NULL) 500 break; 501 502 set_bit(PG_reserved, 503 &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 504 pages[i] = virt_to_page(async->buf_page_list[i].virt_addr); 505 } 506 } 507 if (i == n_pages) { 508 async->prealloc_buf = 509 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 510 } 511 vfree(pages); 512 513 if (async->prealloc_buf == NULL) { 514 /* Some allocation failed above. */ 515 if (async->buf_page_list) { 516 for (i = 0; i < n_pages; i++) { 517 if (async->buf_page_list[i].virt_addr == 518 NULL) { 519 break; 520 } 521 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 522 if (s->async_dma_dir != DMA_NONE) { 523 dma_free_coherent(dev->hw_dev, 524 PAGE_SIZE, 525 async-> 526 buf_page_list 527 [i].virt_addr, 528 async-> 529 buf_page_list 530 [i].dma_addr); 531 } else { 532 free_page((unsigned long) 533 async->buf_page_list 534 [i].virt_addr); 535 } 536 } 537 vfree(async->buf_page_list); 538 async->buf_page_list = NULL; 539 } 540 return -ENOMEM; 541 } 542 async->n_buf_pages = n_pages; 543 } 544 async->prealloc_bufsz = new_size; 545 546 return 0; 547} 548 549/* munging is applied to data by core as it passes between user 550 * and kernel space */ 551unsigned int comedi_buf_munge(struct comedi_async *async, 552 unsigned int num_bytes) 553{ 554 struct comedi_subdevice *s = async->subdevice; 555 unsigned int count = 0; 556 const unsigned num_sample_bytes = bytes_per_sample(s); 557 558 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 559 async->munge_count += num_bytes; 560 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 561 return num_bytes; 562 } 563 /* don't munge partial samples */ 564 num_bytes -= num_bytes % num_sample_bytes; 565 while (count < num_bytes) { 566 int block_size; 567 568 block_size = num_bytes - count; 569 if (block_size < 0) { 570 printk(KERN_WARNING "%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 653 (KERN_INFO "comedi: attempted to write-free more bytes than have been write-allocated.\n"); 654 nbytes = async->buf_write_alloc_count - async->buf_write_count; 655 } 656 async->buf_write_count += nbytes; 657 async->buf_write_ptr += nbytes; 658 comedi_buf_munge(async, async->buf_write_count - async->munge_count); 659 if (async->buf_write_ptr >= async->prealloc_bufsz) 660 async->buf_write_ptr %= async->prealloc_bufsz; 661 662 return nbytes; 663} 664EXPORT_SYMBOL(comedi_buf_write_free); 665 666/* allocates a chunk for the reader from filled (and munged) buffer space */ 667unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) 668{ 669 if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > 670 0) { 671 nbytes = async->munge_count - async->buf_read_alloc_count; 672 } 673 async->buf_read_alloc_count += nbytes; 674 /* barrier insures read of munge_count occurs before we actually read 675 data out of buffer */ 676 smp_rmb(); 677 return nbytes; 678} 679EXPORT_SYMBOL(comedi_buf_read_alloc); 680 681/* transfers control of a chunk from reader to free buffer space */ 682unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) 683{ 684 /* barrier insures data has been read out of 685 * buffer before read count is incremented */ 686 smp_mb(); 687 if ((int)(async->buf_read_count + nbytes - 688 async->buf_read_alloc_count) > 0) { 689 printk 690 ("comedi: attempted to read-free more bytes than have been read-allocated.\n"); 691 nbytes = async->buf_read_alloc_count - async->buf_read_count; 692 } 693 async->buf_read_count += nbytes; 694 async->buf_read_ptr += nbytes; 695 async->buf_read_ptr %= async->prealloc_bufsz; 696 return nbytes; 697} 698EXPORT_SYMBOL(comedi_buf_read_free); 699 700void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, 701 const void *data, unsigned int num_bytes) 702{ 703 unsigned int write_ptr = async->buf_write_ptr + offset; 704 705 if (write_ptr >= async->prealloc_bufsz) 706 write_ptr %= async->prealloc_bufsz; 707 708 while (num_bytes) { 709 unsigned int block_size; 710 711 if (write_ptr + num_bytes > async->prealloc_bufsz) 712 block_size = async->prealloc_bufsz - write_ptr; 713 else 714 block_size = num_bytes; 715 716 memcpy(async->prealloc_buf + write_ptr, data, block_size); 717 718 data += block_size; 719 num_bytes -= block_size; 720 721 write_ptr = 0; 722 } 723} 724EXPORT_SYMBOL(comedi_buf_memcpy_to); 725 726void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, 727 void *dest, unsigned int nbytes) 728{ 729 void *src; 730 unsigned int read_ptr = async->buf_read_ptr + offset; 731 732 if (read_ptr >= async->prealloc_bufsz) 733 read_ptr %= async->prealloc_bufsz; 734 735 while (nbytes) { 736 unsigned int block_size; 737 738 src = async->prealloc_buf + read_ptr; 739 740 if (nbytes >= async->prealloc_bufsz - read_ptr) 741 block_size = async->prealloc_bufsz - read_ptr; 742 else 743 block_size = nbytes; 744 745 memcpy(dest, src, block_size); 746 nbytes -= block_size; 747 dest += block_size; 748 read_ptr = 0; 749 } 750} 751EXPORT_SYMBOL(comedi_buf_memcpy_from); 752 753unsigned int comedi_buf_read_n_available(struct comedi_async *async) 754{ 755 unsigned num_bytes; 756 757 if (async == NULL) 758 return 0; 759 num_bytes = async->munge_count - async->buf_read_count; 760 /* barrier insures the read of munge_count in this 761 query occurs before any following reads of the buffer which 762 might be based on the return value from this query. 763 */ 764 smp_rmb(); 765 return num_bytes; 766} 767EXPORT_SYMBOL(comedi_buf_read_n_available); 768 769int comedi_buf_get(struct comedi_async *async, short *x) 770{ 771 unsigned int n = comedi_buf_read_n_available(async); 772 773 if (n < sizeof(short)) 774 return 0; 775 comedi_buf_read_alloc(async, sizeof(short)); 776 *x = *(short *)(async->prealloc_buf + async->buf_read_ptr); 777 comedi_buf_read_free(async, sizeof(short)); 778 return 1; 779} 780EXPORT_SYMBOL(comedi_buf_get); 781 782int comedi_buf_put(struct comedi_async *async, short x) 783{ 784 unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); 785 786 if (n < sizeof(short)) { 787 async->events |= COMEDI_CB_ERROR; 788 return 0; 789 } 790 *(short *)(async->prealloc_buf + async->buf_write_ptr) = x; 791 comedi_buf_write_free(async, sizeof(short)); 792 return 1; 793} 794EXPORT_SYMBOL(comedi_buf_put); 795 796void comedi_reset_async_buf(struct comedi_async *async) 797{ 798 async->buf_write_alloc_count = 0; 799 async->buf_write_count = 0; 800 async->buf_read_alloc_count = 0; 801 async->buf_read_count = 0; 802 803 async->buf_write_ptr = 0; 804 async->buf_read_ptr = 0; 805 806 async->cur_chan = 0; 807 async->scan_progress = 0; 808 async->munge_chan = 0; 809 async->munge_count = 0; 810 async->munge_ptr = 0; 811 812 async->events = 0; 813} 814EXPORT_SYMBOL(comedi_reset_async_buf); 815 816int comedi_auto_config(struct device *hardware_device, const char *board_name, 817 const int *options, unsigned num_options) 818{ 819 struct comedi_devconfig it; 820 int minor; 821 struct comedi_device_file_info *dev_file_info; 822 int retval; 823 unsigned *private_data = NULL; 824 825 if (!comedi_autoconfig) { 826 dev_set_drvdata(hardware_device, NULL); 827 return 0; 828 } 829 830 minor = comedi_alloc_board_minor(hardware_device); 831 if (minor < 0) 832 return minor; 833 834 private_data = kmalloc(sizeof(unsigned), GFP_KERNEL); 835 if (private_data == NULL) { 836 retval = -ENOMEM; 837 goto cleanup; 838 } 839 *private_data = minor; 840 dev_set_drvdata(hardware_device, private_data); 841 842 dev_file_info = comedi_get_device_file_info(minor); 843 844 memset(&it, 0, sizeof(it)); 845 strncpy(it.board_name, board_name, COMEDI_NAMELEN); 846 it.board_name[COMEDI_NAMELEN - 1] = '\0'; 847 BUG_ON(num_options > COMEDI_NDEVCONFOPTS); 848 memcpy(it.options, options, num_options * sizeof(int)); 849 850 mutex_lock(&dev_file_info->device->mutex); 851 retval = comedi_device_attach(dev_file_info->device, &it); 852 mutex_unlock(&dev_file_info->device->mutex); 853 854cleanup: 855 if (retval < 0) { 856 kfree(private_data); 857 comedi_free_board_minor(minor); 858 } 859 return retval; 860} 861 862void comedi_auto_unconfig(struct device *hardware_device) 863{ 864 unsigned *minor = (unsigned *)dev_get_drvdata(hardware_device); 865 if (minor == NULL) 866 return; 867 868 BUG_ON(*minor >= COMEDI_NUM_BOARD_MINORS); 869 870 comedi_free_board_minor(*minor); 871 dev_set_drvdata(hardware_device, NULL); 872 kfree(minor); 873} 874 875int comedi_pci_auto_config(struct pci_dev *pcidev, const char *board_name) 876{ 877 int options[2]; 878 879 /* pci bus */ 880 options[0] = pcidev->bus->number; 881 /* pci slot */ 882 options[1] = PCI_SLOT(pcidev->devfn); 883 884 return comedi_auto_config(&pcidev->dev, board_name, 885 options, ARRAY_SIZE(options)); 886} 887EXPORT_SYMBOL_GPL(comedi_pci_auto_config); 888 889void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 890{ 891 comedi_auto_unconfig(&pcidev->dev); 892} 893EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); 894 895int comedi_usb_auto_config(struct usb_device *usbdev, const char *board_name) 896{ 897 BUG_ON(usbdev == NULL); 898 return comedi_auto_config(&usbdev->dev, board_name, NULL, 0); 899} 900EXPORT_SYMBOL_GPL(comedi_usb_auto_config); 901 902void comedi_usb_auto_unconfig(struct usb_device *usbdev) 903{ 904 BUG_ON(usbdev == NULL); 905 comedi_auto_unconfig(&usbdev->dev); 906} 907EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig); 908