drivers.c revision d58214b0b8662f1b27d538390ecc49bbea0cd754
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 "comedidev.h" 41#include <linux/highmem.h> /* for SuSE brokenness */ 42#include <linux/vmalloc.h> 43#include <linux/cdev.h> 44#include <linux/dma-mapping.h> 45 46#include <linux/io.h> 47#include <asm/system.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); 56int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 57 unsigned long new_size); 58 59struct comedi_driver *comedi_drivers; 60 61int comedi_modprobe(int minor) 62{ 63 return -EINVAL; 64} 65 66static void cleanup_device(struct comedi_device *dev) 67{ 68 int i; 69 struct comedi_subdevice *s; 70 71 if (dev->subdevices) { 72 for (i = 0; i < dev->n_subdevices; i++) { 73 s = dev->subdevices + i; 74 comedi_free_subdevice_minor(s); 75 if (s->async) { 76 comedi_buf_alloc(dev, s, 0); 77 kfree(s->async); 78 } 79 } 80 kfree(dev->subdevices); 81 dev->subdevices = NULL; 82 dev->n_subdevices = 0; 83 } 84 kfree(dev->private); 85 dev->private = NULL; 86 dev->driver = 0; 87 dev->board_name = NULL; 88 dev->board_ptr = NULL; 89 dev->iobase = 0; 90 dev->irq = 0; 91 dev->read_subdev = NULL; 92 dev->write_subdev = NULL; 93 dev->open = NULL; 94 dev->close = NULL; 95 comedi_set_hw_dev(dev, NULL); 96} 97 98static void __comedi_device_detach(struct comedi_device *dev) 99{ 100 dev->attached = 0; 101 if (dev->driver) 102 dev->driver->detach(dev); 103 else 104 printk(KERN_WARNING "BUG: dev->driver=NULL in comedi_device_detach()\n"); 105 cleanup_device(dev); 106} 107 108void comedi_device_detach(struct comedi_device *dev) 109{ 110 if (!dev->attached) 111 return; 112 __comedi_device_detach(dev); 113} 114 115int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 116{ 117 struct comedi_driver *driv; 118 int ret; 119 120 if (dev->attached) 121 return -EBUSY; 122 123 for (driv = comedi_drivers; driv; driv = driv->next) { 124 if (!try_module_get(driv->module)) { 125 printk 126 (KERN_INFO "comedi: failed to increment module count, skipping\n"); 127 continue; 128 } 129 if (driv->num_names) { 130 dev->board_ptr = comedi_recognize(driv, it->board_name); 131 if (dev->board_ptr == NULL) { 132 module_put(driv->module); 133 continue; 134 } 135 } else { 136 if (strcmp(driv->driver_name, it->board_name)) { 137 module_put(driv->module); 138 continue; 139 } 140 } 141 /* initialize dev->driver here so 142 * comedi_error() can be called from attach */ 143 dev->driver = driv; 144 ret = driv->attach(dev, it); 145 if (ret < 0) { 146 module_put(dev->driver->module); 147 __comedi_device_detach(dev); 148 return ret; 149 } 150 goto attached; 151 } 152 153 /* recognize has failed if we get here */ 154 /* report valid board names before returning error */ 155 for (driv = comedi_drivers; driv; driv = driv->next) { 156 if (!try_module_get(driv->module)) { 157 printk(KERN_INFO "comedi: failed to increment module count\n"); 158 continue; 159 } 160 comedi_report_boards(driv); 161 module_put(driv->module); 162 } 163 return -EIO; 164 165attached: 166 /* do a little post-config cleanup */ 167 ret = postconfig(dev); 168 module_put(dev->driver->module); 169 if (ret < 0) { 170 __comedi_device_detach(dev); 171 return ret; 172 } 173 174 if (!dev->board_name) { 175 printk(KERN_WARNING "BUG: dev->board_name=<%p>\n", dev->board_name); 176 dev->board_name = "BUG"; 177 } 178 smp_wmb(); 179 dev->attached = 1; 180 181 return 0; 182} 183 184int comedi_driver_register(struct comedi_driver *driver) 185{ 186 driver->next = comedi_drivers; 187 comedi_drivers = driver; 188 189 return 0; 190} 191EXPORT_SYMBOL(comedi_driver_register); 192 193int comedi_driver_unregister(struct comedi_driver *driver) 194{ 195 struct comedi_driver *prev; 196 int i; 197 198 /* check for devices using this driver */ 199 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 200 struct comedi_device_file_info *dev_file_info = 201 comedi_get_device_file_info(i); 202 struct comedi_device *dev; 203 204 if (dev_file_info == NULL) 205 continue; 206 dev = dev_file_info->device; 207 208 mutex_lock(&dev->mutex); 209 if (dev->attached && dev->driver == driver) { 210 if (dev->use_count) 211 printk 212 (KERN_WARNING "BUG! detaching device with use_count=%d\n", 213 dev->use_count); 214 comedi_device_detach(dev); 215 } 216 mutex_unlock(&dev->mutex); 217 } 218 219 if (comedi_drivers == driver) { 220 comedi_drivers = driver->next; 221 return 0; 222 } 223 224 for (prev = comedi_drivers; prev->next; prev = prev->next) { 225 if (prev->next == driver) { 226 prev->next = driver->next; 227 return 0; 228 } 229 } 230 return -EINVAL; 231} 232EXPORT_SYMBOL(comedi_driver_unregister); 233 234static int postconfig(struct comedi_device *dev) 235{ 236 int i; 237 struct comedi_subdevice *s; 238 struct comedi_async *async = NULL; 239 int ret; 240 241 for (i = 0; i < dev->n_subdevices; i++) { 242 s = dev->subdevices + i; 243 244 if (s->type == COMEDI_SUBD_UNUSED) 245 continue; 246 247 if (s->len_chanlist == 0) 248 s->len_chanlist = 1; 249 250 if (s->do_cmd) { 251 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 252 SDF_CMD_WRITE)) == 0); 253 BUG_ON(!s->do_cmdtest); 254 255 async = 256 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 257 if (async == NULL) { 258 printk(KERN_INFO "failed to allocate async struct\n"); 259 return -ENOMEM; 260 } 261 init_waitqueue_head(&async->wait_head); 262 async->subdevice = s; 263 s->async = async; 264 265#define DEFAULT_BUF_MAXSIZE (64*1024) 266#define DEFAULT_BUF_SIZE (64*1024) 267 268 async->max_bufsize = DEFAULT_BUF_MAXSIZE; 269 270 async->prealloc_buf = NULL; 271 async->prealloc_bufsz = 0; 272 if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) { 273 printk(KERN_INFO "Buffer allocation failed\n"); 274 return -ENOMEM; 275 } 276 if (s->buf_change) { 277 ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE); 278 if (ret < 0) 279 return ret; 280 } 281 comedi_alloc_subdevice_minor(dev, s); 282 } 283 284 if (!s->range_table && !s->range_table_list) 285 s->range_table = &range_unknown; 286 287 if (!s->insn_read && s->insn_bits) 288 s->insn_read = insn_rw_emulate_bits; 289 if (!s->insn_write && s->insn_bits) 290 s->insn_write = insn_rw_emulate_bits; 291 292 if (!s->insn_read) 293 s->insn_read = insn_inval; 294 if (!s->insn_write) 295 s->insn_write = insn_inval; 296 if (!s->insn_bits) 297 s->insn_bits = insn_inval; 298 if (!s->insn_config) 299 s->insn_config = insn_inval; 300 301 if (!s->poll) 302 s->poll = poll_invalid; 303 } 304 305 return 0; 306} 307 308/* generic recognize function for drivers 309 * that register their supported board names */ 310void *comedi_recognize(struct comedi_driver *driv, const char *name) 311{ 312 unsigned i; 313 const char *const *name_ptr = driv->board_name; 314 for (i = 0; i < driv->num_names; i++) { 315 if (strcmp(*name_ptr, name) == 0) 316 return (void *)name_ptr; 317 name_ptr = 318 (const char *const *)((const char *)name_ptr + 319 driv->offset); 320 } 321 322 return NULL; 323} 324 325void comedi_report_boards(struct comedi_driver *driv) 326{ 327 unsigned int i; 328 const char *const *name_ptr; 329 330 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 331 driv->driver_name); 332 333 name_ptr = driv->board_name; 334 for (i = 0; i < driv->num_names; i++) { 335 printk(KERN_INFO " %s\n", *name_ptr); 336 name_ptr = (const char **)((char *)name_ptr + driv->offset); 337 } 338 339 if (driv->num_names == 0) 340 printk(KERN_INFO " %s\n", driv->driver_name); 341} 342 343static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 344{ 345 return -EINVAL; 346} 347 348int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 349 struct comedi_insn *insn, unsigned int *data) 350{ 351 return -EINVAL; 352} 353 354static int insn_rw_emulate_bits(struct comedi_device *dev, 355 struct comedi_subdevice *s, 356 struct comedi_insn *insn, unsigned int *data) 357{ 358 struct comedi_insn new_insn; 359 int ret; 360 static const unsigned channels_per_bitfield = 32; 361 362 unsigned chan = CR_CHAN(insn->chanspec); 363 const unsigned base_bitfield_channel = 364 (chan < channels_per_bitfield) ? 0 : chan; 365 unsigned int new_data[2]; 366 memset(new_data, 0, sizeof(new_data)); 367 memset(&new_insn, 0, sizeof(new_insn)); 368 new_insn.insn = INSN_BITS; 369 new_insn.chanspec = base_bitfield_channel; 370 new_insn.n = 2; 371 new_insn.data = new_data; 372 new_insn.subdev = insn->subdev; 373 374 if (insn->insn == INSN_WRITE) { 375 if (!(s->subdev_flags & SDF_WRITABLE)) 376 return -EINVAL; 377 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 378 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) : 0; /* bits */ 379 } 380 381 ret = s->insn_bits(dev, s, &new_insn, new_data); 382 if (ret < 0) 383 return ret; 384 385 if (insn->insn == INSN_READ) 386 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 387 388 return 1; 389} 390 391static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr) 392{ 393 unsigned long ret = 0UL; 394 pmd_t *pmd; 395 pte_t *ptep, pte; 396 pud_t *pud; 397 398 if (!pgd_none(*pgd)) { 399 pud = pud_offset(pgd, adr); 400 pmd = pmd_offset(pud, adr); 401 if (!pmd_none(*pmd)) { 402 ptep = pte_offset_kernel(pmd, adr); 403 pte = *ptep; 404 if (pte_present(pte)) { 405 ret = (unsigned long) 406 page_address(pte_page(pte)); 407 ret |= (adr & (PAGE_SIZE - 1)); 408 } 409 } 410 } 411 return ret; 412} 413 414static inline unsigned long kvirt_to_kva(unsigned long adr) 415{ 416 unsigned long va, kva; 417 418 va = adr; 419 kva = uvirt_to_kva(pgd_offset_k(va), va); 420 421 return kva; 422} 423 424int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 425 unsigned long new_size) 426{ 427 struct comedi_async *async = s->async; 428 429 /* Round up new_size to multiple of PAGE_SIZE */ 430 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 431 432 /* if no change is required, do nothing */ 433 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 434 return 0; 435 436 /* deallocate old buffer */ 437 if (async->prealloc_buf) { 438 vunmap(async->prealloc_buf); 439 async->prealloc_buf = NULL; 440 async->prealloc_bufsz = 0; 441 } 442 if (async->buf_page_list) { 443 unsigned i; 444 for (i = 0; i < async->n_buf_pages; ++i) { 445 if (async->buf_page_list[i].virt_addr) { 446 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 447 if (s->async_dma_dir != DMA_NONE) { 448 dma_free_coherent(dev->hw_dev, 449 PAGE_SIZE, 450 async-> 451 buf_page_list 452 [i].virt_addr, 453 async-> 454 buf_page_list 455 [i].dma_addr); 456 } else { 457 free_page((unsigned long) 458 async->buf_page_list[i]. 459 virt_addr); 460 } 461 } 462 } 463 vfree(async->buf_page_list); 464 async->buf_page_list = NULL; 465 async->n_buf_pages = 0; 466 } 467 /* allocate new buffer */ 468 if (new_size) { 469 unsigned i = 0; 470 unsigned n_pages = new_size >> PAGE_SHIFT; 471 struct page **pages = NULL; 472 473 async->buf_page_list = 474 vmalloc(sizeof(struct comedi_buf_page) * n_pages); 475 if (async->buf_page_list) { 476 memset(async->buf_page_list, 0, 477 sizeof(struct comedi_buf_page) * n_pages); 478 pages = vmalloc(sizeof(struct page *) * n_pages); 479 } 480 if (pages) { 481 for (i = 0; i < n_pages; i++) { 482 if (s->async_dma_dir != DMA_NONE) { 483 async->buf_page_list[i].virt_addr = 484 dma_alloc_coherent(dev->hw_dev, 485 PAGE_SIZE, 486 &async-> 487 buf_page_list 488 [i].dma_addr, 489 GFP_KERNEL | 490 __GFP_COMP); 491 } else { 492 async->buf_page_list[i].virt_addr = 493 (void *) 494 get_zeroed_page(GFP_KERNEL); 495 } 496 if (async->buf_page_list[i].virt_addr == NULL) 497 break; 498 499 set_bit(PG_reserved, 500 &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 501 pages[i] = virt_to_page(async->buf_page_list[i].virt_addr); 502 } 503 } 504 if (i == n_pages) { 505 async->prealloc_buf = 506 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 507 } 508 vfree(pages); 509 510 if (async->prealloc_buf == NULL) { 511 /* Some allocation failed above. */ 512 if (async->buf_page_list) { 513 for (i = 0; i < n_pages; i++) { 514 if (async->buf_page_list[i].virt_addr == 515 NULL) { 516 break; 517 } 518 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 519 if (s->async_dma_dir != DMA_NONE) { 520 dma_free_coherent(dev->hw_dev, 521 PAGE_SIZE, 522 async-> 523 buf_page_list 524 [i].virt_addr, 525 async-> 526 buf_page_list 527 [i].dma_addr); 528 } else { 529 free_page((unsigned long) 530 async->buf_page_list 531 [i].virt_addr); 532 } 533 } 534 vfree(async->buf_page_list); 535 async->buf_page_list = NULL; 536 } 537 return -ENOMEM; 538 } 539 async->n_buf_pages = n_pages; 540 } 541 async->prealloc_bufsz = new_size; 542 543 return 0; 544} 545 546/* munging is applied to data by core as it passes between user 547 * and kernel space */ 548unsigned int comedi_buf_munge(struct comedi_async *async, 549 unsigned int num_bytes) 550{ 551 struct comedi_subdevice *s = async->subdevice; 552 unsigned int count = 0; 553 const unsigned num_sample_bytes = bytes_per_sample(s); 554 555 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 556 async->munge_count += num_bytes; 557 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 558 return num_bytes; 559 } 560 /* don't munge partial samples */ 561 num_bytes -= num_bytes % num_sample_bytes; 562 while (count < num_bytes) { 563 int block_size; 564 565 block_size = num_bytes - count; 566 if (block_size < 0) { 567 printk(KERN_WARNING "%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 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} 811EXPORT_SYMBOL(comedi_reset_async_buf); 812 813int comedi_auto_config(struct device *hardware_device, const char *board_name, 814 const int *options, 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 859void 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} 884 885void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 886{ 887 comedi_auto_unconfig(&pcidev->dev); 888} 889 890int comedi_usb_auto_config(struct usb_device *usbdev, const char *board_name) 891{ 892 BUG_ON(usbdev == NULL); 893 return comedi_auto_config(&usbdev->dev, board_name, NULL, 0); 894} 895 896void comedi_usb_auto_unconfig(struct usb_device *usbdev) 897{ 898 BUG_ON(usbdev == NULL); 899 comedi_auto_unconfig(&usbdev->dev); 900} 901