drivers.c revision aad4029a49e17d8529b8b802d4ecd774ef941f7c
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", 176 dev->board_name); 177 dev->board_name = "BUG"; 178 } 179 smp_wmb(); 180 dev->attached = 1; 181 182 return 0; 183} 184 185int comedi_driver_register(struct comedi_driver *driver) 186{ 187 driver->next = comedi_drivers; 188 comedi_drivers = driver; 189 190 return 0; 191} 192EXPORT_SYMBOL(comedi_driver_register); 193 194int comedi_driver_unregister(struct comedi_driver *driver) 195{ 196 struct comedi_driver *prev; 197 int i; 198 199 /* check for devices using this driver */ 200 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 201 struct comedi_device_file_info *dev_file_info = 202 comedi_get_device_file_info(i); 203 struct comedi_device *dev; 204 205 if (dev_file_info == NULL) 206 continue; 207 dev = dev_file_info->device; 208 209 mutex_lock(&dev->mutex); 210 if (dev->attached && dev->driver == driver) { 211 if (dev->use_count) 212 printk 213 (KERN_WARNING "BUG! detaching device with use_count=%d\n", 214 dev->use_count); 215 comedi_device_detach(dev); 216 } 217 mutex_unlock(&dev->mutex); 218 } 219 220 if (comedi_drivers == driver) { 221 comedi_drivers = driver->next; 222 return 0; 223 } 224 225 for (prev = comedi_drivers; prev->next; prev = prev->next) { 226 if (prev->next == driver) { 227 prev->next = driver->next; 228 return 0; 229 } 230 } 231 return -EINVAL; 232} 233EXPORT_SYMBOL(comedi_driver_unregister); 234 235static int postconfig(struct comedi_device *dev) 236{ 237 int i; 238 struct comedi_subdevice *s; 239 struct comedi_async *async = NULL; 240 int ret; 241 242 for (i = 0; i < dev->n_subdevices; i++) { 243 s = dev->subdevices + i; 244 245 if (s->type == COMEDI_SUBD_UNUSED) 246 continue; 247 248 if (s->len_chanlist == 0) 249 s->len_chanlist = 1; 250 251 if (s->do_cmd) { 252 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 253 SDF_CMD_WRITE)) == 0); 254 BUG_ON(!s->do_cmdtest); 255 256 async = 257 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 258 if (async == NULL) { 259 printk(KERN_INFO "failed to allocate async struct\n"); 260 return -ENOMEM; 261 } 262 init_waitqueue_head(&async->wait_head); 263 async->subdevice = s; 264 s->async = async; 265 266#define DEFAULT_BUF_MAXSIZE (64*1024) 267#define DEFAULT_BUF_SIZE (64*1024) 268 269 async->max_bufsize = DEFAULT_BUF_MAXSIZE; 270 271 async->prealloc_buf = NULL; 272 async->prealloc_bufsz = 0; 273 if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) { 274 printk(KERN_INFO "Buffer allocation failed\n"); 275 return -ENOMEM; 276 } 277 if (s->buf_change) { 278 ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE); 279 if (ret < 0) 280 return ret; 281 } 282 comedi_alloc_subdevice_minor(dev, s); 283 } 284 285 if (!s->range_table && !s->range_table_list) 286 s->range_table = &range_unknown; 287 288 if (!s->insn_read && s->insn_bits) 289 s->insn_read = insn_rw_emulate_bits; 290 if (!s->insn_write && s->insn_bits) 291 s->insn_write = insn_rw_emulate_bits; 292 293 if (!s->insn_read) 294 s->insn_read = insn_inval; 295 if (!s->insn_write) 296 s->insn_write = insn_inval; 297 if (!s->insn_bits) 298 s->insn_bits = insn_inval; 299 if (!s->insn_config) 300 s->insn_config = insn_inval; 301 302 if (!s->poll) 303 s->poll = poll_invalid; 304 } 305 306 return 0; 307} 308 309/* generic recognize function for drivers 310 * that register their supported board names */ 311void *comedi_recognize(struct comedi_driver *driv, const char *name) 312{ 313 unsigned i; 314 const char *const *name_ptr = driv->board_name; 315 for (i = 0; i < driv->num_names; i++) { 316 if (strcmp(*name_ptr, name) == 0) 317 return (void *)name_ptr; 318 name_ptr = 319 (const char *const *)((const char *)name_ptr + 320 driv->offset); 321 } 322 323 return NULL; 324} 325 326void comedi_report_boards(struct comedi_driver *driv) 327{ 328 unsigned int i; 329 const char *const *name_ptr; 330 331 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 332 driv->driver_name); 333 334 name_ptr = driv->board_name; 335 for (i = 0; i < driv->num_names; i++) { 336 printk(KERN_INFO " %s\n", *name_ptr); 337 name_ptr = (const char **)((char *)name_ptr + driv->offset); 338 } 339 340 if (driv->num_names == 0) 341 printk(KERN_INFO " %s\n", driv->driver_name); 342} 343 344static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 345{ 346 return -EINVAL; 347} 348 349int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 350 struct comedi_insn *insn, unsigned int *data) 351{ 352 return -EINVAL; 353} 354 355static int insn_rw_emulate_bits(struct comedi_device *dev, 356 struct comedi_subdevice *s, 357 struct comedi_insn *insn, unsigned int *data) 358{ 359 struct comedi_insn new_insn; 360 int ret; 361 static const unsigned channels_per_bitfield = 32; 362 363 unsigned chan = CR_CHAN(insn->chanspec); 364 const unsigned base_bitfield_channel = 365 (chan < channels_per_bitfield) ? 0 : chan; 366 unsigned int new_data[2]; 367 memset(new_data, 0, sizeof(new_data)); 368 memset(&new_insn, 0, sizeof(new_insn)); 369 new_insn.insn = INSN_BITS; 370 new_insn.chanspec = base_bitfield_channel; 371 new_insn.n = 2; 372 new_insn.data = new_data; 373 new_insn.subdev = insn->subdev; 374 375 if (insn->insn == INSN_WRITE) { 376 if (!(s->subdev_flags & SDF_WRITABLE)) 377 return -EINVAL; 378 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 379 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 380 : 0; /* bits */ 381 } 382 383 ret = s->insn_bits(dev, s, &new_insn, new_data); 384 if (ret < 0) 385 return ret; 386 387 if (insn->insn == INSN_READ) 388 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 389 390 return 1; 391} 392 393static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr) 394{ 395 unsigned long ret = 0UL; 396 pmd_t *pmd; 397 pte_t *ptep, pte; 398 pud_t *pud; 399 400 if (!pgd_none(*pgd)) { 401 pud = pud_offset(pgd, adr); 402 pmd = pmd_offset(pud, adr); 403 if (!pmd_none(*pmd)) { 404 ptep = pte_offset_kernel(pmd, adr); 405 pte = *ptep; 406 if (pte_present(pte)) { 407 ret = (unsigned long) 408 page_address(pte_page(pte)); 409 ret |= (adr & (PAGE_SIZE - 1)); 410 } 411 } 412 } 413 return ret; 414} 415 416static inline unsigned long kvirt_to_kva(unsigned long adr) 417{ 418 unsigned long va, kva; 419 420 va = adr; 421 kva = uvirt_to_kva(pgd_offset_k(va), va); 422 423 return kva; 424} 425 426int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 427 unsigned long new_size) 428{ 429 struct comedi_async *async = s->async; 430 431 /* Round up new_size to multiple of PAGE_SIZE */ 432 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 433 434 /* if no change is required, do nothing */ 435 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 436 return 0; 437 438 /* deallocate old buffer */ 439 if (async->prealloc_buf) { 440 vunmap(async->prealloc_buf); 441 async->prealloc_buf = NULL; 442 async->prealloc_bufsz = 0; 443 } 444 if (async->buf_page_list) { 445 unsigned i; 446 for (i = 0; i < async->n_buf_pages; ++i) { 447 if (async->buf_page_list[i].virt_addr) { 448 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 449 if (s->async_dma_dir != DMA_NONE) { 450 dma_free_coherent(dev->hw_dev, 451 PAGE_SIZE, 452 async-> 453 buf_page_list 454 [i].virt_addr, 455 async-> 456 buf_page_list 457 [i].dma_addr); 458 } else { 459 free_page((unsigned long) 460 async->buf_page_list[i]. 461 virt_addr); 462 } 463 } 464 } 465 vfree(async->buf_page_list); 466 async->buf_page_list = NULL; 467 async->n_buf_pages = 0; 468 } 469 /* allocate new buffer */ 470 if (new_size) { 471 unsigned i = 0; 472 unsigned n_pages = new_size >> PAGE_SHIFT; 473 struct page **pages = NULL; 474 475 async->buf_page_list = 476 vmalloc(sizeof(struct comedi_buf_page) * n_pages); 477 if (async->buf_page_list) { 478 memset(async->buf_page_list, 0, 479 sizeof(struct comedi_buf_page) * n_pages); 480 pages = vmalloc(sizeof(struct page *) * n_pages); 481 } 482 if (pages) { 483 for (i = 0; i < n_pages; i++) { 484 if (s->async_dma_dir != DMA_NONE) { 485 async->buf_page_list[i].virt_addr = 486 dma_alloc_coherent(dev->hw_dev, 487 PAGE_SIZE, 488 &async-> 489 buf_page_list 490 [i].dma_addr, 491 GFP_KERNEL | 492 __GFP_COMP); 493 } else { 494 async->buf_page_list[i].virt_addr = 495 (void *) 496 get_zeroed_page(GFP_KERNEL); 497 } 498 if (async->buf_page_list[i].virt_addr == NULL) 499 break; 500 501 set_bit(PG_reserved, 502 &(virt_to_page(async->buf_page_list[i].virt_addr)->flags)); 503 pages[i] = virt_to_page(async->buf_page_list[i].virt_addr); 504 } 505 } 506 if (i == n_pages) { 507 async->prealloc_buf = 508 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 509 } 510 vfree(pages); 511 512 if (async->prealloc_buf == NULL) { 513 /* Some allocation failed above. */ 514 if (async->buf_page_list) { 515 for (i = 0; i < n_pages; i++) { 516 if (async->buf_page_list[i].virt_addr == 517 NULL) { 518 break; 519 } 520 clear_bit(PG_reserved, &(virt_to_page(async->buf_page_list[i].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 */ 550unsigned 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 "%s: %s: bug! block_size is negative\n", 570 __FILE__, __func__); 571 break; 572 } 573 if ((int)(async->munge_ptr + block_size - 574 async->prealloc_bufsz) > 0) 575 block_size = async->prealloc_bufsz - async->munge_ptr; 576 577 s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, 578 block_size, async->munge_chan); 579 580 smp_wmb(); /* barrier insures data is munged in buffer 581 * before munge_count is incremented */ 582 583 async->munge_chan += block_size / num_sample_bytes; 584 async->munge_chan %= async->cmd.chanlist_len; 585 async->munge_count += block_size; 586 async->munge_ptr += block_size; 587 async->munge_ptr %= async->prealloc_bufsz; 588 count += block_size; 589 } 590 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 591 return count; 592} 593 594unsigned int comedi_buf_write_n_available(struct comedi_async *async) 595{ 596 unsigned int free_end; 597 unsigned int nbytes; 598 599 if (async == NULL) 600 return 0; 601 602 free_end = async->buf_read_count + async->prealloc_bufsz; 603 nbytes = free_end - async->buf_write_alloc_count; 604 nbytes -= nbytes % bytes_per_sample(async->subdevice); 605 /* barrier insures the read of buf_read_count in this 606 query occurs before any following writes to the buffer which 607 might be based on the return value from this query. 608 */ 609 smp_mb(); 610 return nbytes; 611} 612 613/* allocates chunk for the writer from free buffer space */ 614unsigned int comedi_buf_write_alloc(struct comedi_async *async, 615 unsigned int nbytes) 616{ 617 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 618 619 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 620 nbytes = free_end - async->buf_write_alloc_count; 621 622 async->buf_write_alloc_count += nbytes; 623 /* barrier insures the read of buf_read_count above occurs before 624 we write data to the write-alloc'ed buffer space */ 625 smp_mb(); 626 return nbytes; 627} 628EXPORT_SYMBOL(comedi_buf_write_alloc); 629 630/* allocates nothing unless it can completely fulfill the request */ 631unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, 632 unsigned int nbytes) 633{ 634 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 635 636 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 637 nbytes = 0; 638 639 async->buf_write_alloc_count += nbytes; 640 /* barrier insures the read of buf_read_count above occurs before 641 we write data to the write-alloc'ed buffer space */ 642 smp_mb(); 643 return nbytes; 644} 645 646/* transfers a chunk from writer to filled buffer space */ 647unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) 648{ 649 if ((int)(async->buf_write_count + nbytes - 650 async->buf_write_alloc_count) > 0) { 651 printk 652 (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 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} 813EXPORT_SYMBOL(comedi_reset_async_buf); 814 815int comedi_auto_config(struct device *hardware_device, const char *board_name, 816 const int *options, 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 861void 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