drivers.c revision 9ffc93f203c18a70623f21950f1dd473c9ec48cd
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 46#include "comedidev.h" 47#include "internal.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); 56 57struct comedi_driver *comedi_drivers; 58 59static void cleanup_device(struct comedi_device *dev) 60{ 61 int i; 62 struct comedi_subdevice *s; 63 64 if (dev->subdevices) { 65 for (i = 0; i < dev->n_subdevices; i++) { 66 s = dev->subdevices + i; 67 comedi_free_subdevice_minor(s); 68 if (s->async) { 69 comedi_buf_alloc(dev, s, 0); 70 kfree(s->async); 71 } 72 } 73 kfree(dev->subdevices); 74 dev->subdevices = NULL; 75 dev->n_subdevices = 0; 76 } 77 kfree(dev->private); 78 dev->private = NULL; 79 dev->driver = NULL; 80 dev->board_name = NULL; 81 dev->board_ptr = NULL; 82 dev->iobase = 0; 83 dev->irq = 0; 84 dev->read_subdev = NULL; 85 dev->write_subdev = NULL; 86 dev->open = NULL; 87 dev->close = NULL; 88 comedi_set_hw_dev(dev, NULL); 89} 90 91static void __comedi_device_detach(struct comedi_device *dev) 92{ 93 dev->attached = 0; 94 if (dev->driver) 95 dev->driver->detach(dev); 96 else 97 printk(KERN_WARNING 98 "BUG: dev->driver=NULL in comedi_device_detach()\n"); 99 cleanup_device(dev); 100} 101 102void comedi_device_detach(struct comedi_device *dev) 103{ 104 if (!dev->attached) 105 return; 106 __comedi_device_detach(dev); 107} 108 109int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 110{ 111 struct comedi_driver *driv; 112 int ret; 113 114 if (dev->attached) 115 return -EBUSY; 116 117 for (driv = comedi_drivers; driv; driv = driv->next) { 118 if (!try_module_get(driv->module)) { 119 printk(KERN_INFO "comedi: failed to increment module count, skipping\n"); 120 continue; 121 } 122 if (driv->num_names) { 123 dev->board_ptr = comedi_recognize(driv, it->board_name); 124 if (dev->board_ptr == NULL) { 125 module_put(driv->module); 126 continue; 127 } 128 } else { 129 if (strcmp(driv->driver_name, it->board_name)) { 130 module_put(driv->module); 131 continue; 132 } 133 } 134 /* initialize dev->driver here so 135 * comedi_error() can be called from attach */ 136 dev->driver = driv; 137 ret = driv->attach(dev, it); 138 if (ret < 0) { 139 module_put(dev->driver->module); 140 __comedi_device_detach(dev); 141 return ret; 142 } 143 goto attached; 144 } 145 146 /* recognize has failed if we get here */ 147 /* report valid board names before returning error */ 148 for (driv = comedi_drivers; driv; driv = driv->next) { 149 if (!try_module_get(driv->module)) { 150 printk(KERN_INFO 151 "comedi: failed to increment module count\n"); 152 continue; 153 } 154 comedi_report_boards(driv); 155 module_put(driv->module); 156 } 157 return -EIO; 158 159attached: 160 /* do a little post-config cleanup */ 161 ret = postconfig(dev); 162 module_put(dev->driver->module); 163 if (ret < 0) { 164 __comedi_device_detach(dev); 165 return ret; 166 } 167 168 if (!dev->board_name) { 169 printk(KERN_WARNING "BUG: dev->board_name=<%p>\n", 170 dev->board_name); 171 dev->board_name = "BUG"; 172 } 173 smp_wmb(); 174 dev->attached = 1; 175 176 return 0; 177} 178 179int comedi_driver_register(struct comedi_driver *driver) 180{ 181 driver->next = comedi_drivers; 182 comedi_drivers = driver; 183 184 return 0; 185} 186EXPORT_SYMBOL(comedi_driver_register); 187 188int comedi_driver_unregister(struct comedi_driver *driver) 189{ 190 struct comedi_driver *prev; 191 int i; 192 193 /* check for devices using this driver */ 194 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 195 struct comedi_device_file_info *dev_file_info = 196 comedi_get_device_file_info(i); 197 struct comedi_device *dev; 198 199 if (dev_file_info == NULL) 200 continue; 201 dev = dev_file_info->device; 202 203 mutex_lock(&dev->mutex); 204 if (dev->attached && dev->driver == driver) { 205 if (dev->use_count) 206 printk(KERN_WARNING "BUG! detaching device with use_count=%d\n", 207 dev->use_count); 208 comedi_device_detach(dev); 209 } 210 mutex_unlock(&dev->mutex); 211 } 212 213 if (comedi_drivers == driver) { 214 comedi_drivers = driver->next; 215 return 0; 216 } 217 218 for (prev = comedi_drivers; prev->next; prev = prev->next) { 219 if (prev->next == driver) { 220 prev->next = driver->next; 221 return 0; 222 } 223 } 224 return -EINVAL; 225} 226EXPORT_SYMBOL(comedi_driver_unregister); 227 228static int postconfig(struct comedi_device *dev) 229{ 230 int i; 231 struct comedi_subdevice *s; 232 struct comedi_async *async = NULL; 233 int ret; 234 235 for (i = 0; i < dev->n_subdevices; i++) { 236 s = dev->subdevices + i; 237 238 if (s->type == COMEDI_SUBD_UNUSED) 239 continue; 240 241 if (s->len_chanlist == 0) 242 s->len_chanlist = 1; 243 244 if (s->do_cmd) { 245 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 246 SDF_CMD_WRITE)) == 0); 247 BUG_ON(!s->do_cmdtest); 248 249 async = 250 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 251 if (async == NULL) { 252 printk(KERN_INFO 253 "failed to allocate async struct\n"); 254 return -ENOMEM; 255 } 256 init_waitqueue_head(&async->wait_head); 257 async->subdevice = s; 258 s->async = async; 259 260#define DEFAULT_BUF_MAXSIZE (64*1024) 261#define DEFAULT_BUF_SIZE (64*1024) 262 263 async->max_bufsize = DEFAULT_BUF_MAXSIZE; 264 265 async->prealloc_buf = NULL; 266 async->prealloc_bufsz = 0; 267 if (comedi_buf_alloc(dev, s, DEFAULT_BUF_SIZE) < 0) { 268 printk(KERN_INFO "Buffer allocation failed\n"); 269 return -ENOMEM; 270 } 271 if (s->buf_change) { 272 ret = s->buf_change(dev, s, DEFAULT_BUF_SIZE); 273 if (ret < 0) 274 return ret; 275 } 276 comedi_alloc_subdevice_minor(dev, s); 277 } 278 279 if (!s->range_table && !s->range_table_list) 280 s->range_table = &range_unknown; 281 282 if (!s->insn_read && s->insn_bits) 283 s->insn_read = insn_rw_emulate_bits; 284 if (!s->insn_write && s->insn_bits) 285 s->insn_write = insn_rw_emulate_bits; 286 287 if (!s->insn_read) 288 s->insn_read = insn_inval; 289 if (!s->insn_write) 290 s->insn_write = insn_inval; 291 if (!s->insn_bits) 292 s->insn_bits = insn_inval; 293 if (!s->insn_config) 294 s->insn_config = insn_inval; 295 296 if (!s->poll) 297 s->poll = poll_invalid; 298 } 299 300 return 0; 301} 302 303/* generic recognize function for drivers 304 * that register their supported board names */ 305static void *comedi_recognize(struct comedi_driver *driv, const char *name) 306{ 307 unsigned i; 308 const char *const *name_ptr = driv->board_name; 309 for (i = 0; i < driv->num_names; i++) { 310 if (strcmp(*name_ptr, name) == 0) 311 return (void *)name_ptr; 312 name_ptr = 313 (const char *const *)((const char *)name_ptr + 314 driv->offset); 315 } 316 317 return NULL; 318} 319 320static void comedi_report_boards(struct comedi_driver *driv) 321{ 322 unsigned int i; 323 const char *const *name_ptr; 324 325 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 326 driv->driver_name); 327 328 name_ptr = driv->board_name; 329 for (i = 0; i < driv->num_names; i++) { 330 printk(KERN_INFO " %s\n", *name_ptr); 331 name_ptr = (const char **)((char *)name_ptr + driv->offset); 332 } 333 334 if (driv->num_names == 0) 335 printk(KERN_INFO " %s\n", driv->driver_name); 336} 337 338static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 339{ 340 return -EINVAL; 341} 342 343int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 344 struct comedi_insn *insn, unsigned int *data) 345{ 346 return -EINVAL; 347} 348 349static int insn_rw_emulate_bits(struct comedi_device *dev, 350 struct comedi_subdevice *s, 351 struct comedi_insn *insn, unsigned int *data) 352{ 353 struct comedi_insn new_insn; 354 int ret; 355 static const unsigned channels_per_bitfield = 32; 356 357 unsigned chan = CR_CHAN(insn->chanspec); 358 const unsigned base_bitfield_channel = 359 (chan < channels_per_bitfield) ? 0 : chan; 360 unsigned int new_data[2]; 361 memset(new_data, 0, sizeof(new_data)); 362 memset(&new_insn, 0, sizeof(new_insn)); 363 new_insn.insn = INSN_BITS; 364 new_insn.chanspec = base_bitfield_channel; 365 new_insn.n = 2; 366 new_insn.data = new_data; 367 new_insn.subdev = insn->subdev; 368 369 if (insn->insn == INSN_WRITE) { 370 if (!(s->subdev_flags & SDF_WRITABLE)) 371 return -EINVAL; 372 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 373 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 374 : 0; /* bits */ 375 } 376 377 ret = s->insn_bits(dev, s, &new_insn, new_data); 378 if (ret < 0) 379 return ret; 380 381 if (insn->insn == INSN_READ) 382 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 383 384 return 1; 385} 386 387static inline unsigned long uvirt_to_kva(pgd_t *pgd, unsigned long adr) 388{ 389 unsigned long ret = 0UL; 390 pmd_t *pmd; 391 pte_t *ptep, pte; 392 pud_t *pud; 393 394 if (!pgd_none(*pgd)) { 395 pud = pud_offset(pgd, adr); 396 pmd = pmd_offset(pud, adr); 397 if (!pmd_none(*pmd)) { 398 ptep = pte_offset_kernel(pmd, adr); 399 pte = *ptep; 400 if (pte_present(pte)) { 401 ret = (unsigned long) 402 page_address(pte_page(pte)); 403 ret |= (adr & (PAGE_SIZE - 1)); 404 } 405 } 406 } 407 return ret; 408} 409 410static inline unsigned long kvirt_to_kva(unsigned long adr) 411{ 412 unsigned long va, kva; 413 414 va = adr; 415 kva = uvirt_to_kva(pgd_offset_k(va), va); 416 417 return kva; 418} 419 420int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 421 unsigned long new_size) 422{ 423 struct comedi_async *async = s->async; 424 425 /* Round up new_size to multiple of PAGE_SIZE */ 426 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 427 428 /* if no change is required, do nothing */ 429 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 430 return 0; 431 432 /* deallocate old buffer */ 433 if (async->prealloc_buf) { 434 vunmap(async->prealloc_buf); 435 async->prealloc_buf = NULL; 436 async->prealloc_bufsz = 0; 437 } 438 if (async->buf_page_list) { 439 unsigned i; 440 for (i = 0; i < async->n_buf_pages; ++i) { 441 if (async->buf_page_list[i].virt_addr) { 442 clear_bit(PG_reserved, 443 &(virt_to_page(async->buf_page_list[i]. 444 virt_addr)->flags)); 445 if (s->async_dma_dir != DMA_NONE) { 446 dma_free_coherent(dev->hw_dev, 447 PAGE_SIZE, 448 async-> 449 buf_page_list 450 [i].virt_addr, 451 async-> 452 buf_page_list 453 [i].dma_addr); 454 } else { 455 free_page((unsigned long) 456 async->buf_page_list[i]. 457 virt_addr); 458 } 459 } 460 } 461 vfree(async->buf_page_list); 462 async->buf_page_list = NULL; 463 async->n_buf_pages = 0; 464 } 465 /* allocate new buffer */ 466 if (new_size) { 467 unsigned i = 0; 468 unsigned n_pages = new_size >> PAGE_SHIFT; 469 struct page **pages = NULL; 470 471 async->buf_page_list = 472 vzalloc(sizeof(struct comedi_buf_page) * n_pages); 473 if (async->buf_page_list) 474 pages = vmalloc(sizeof(struct page *) * n_pages); 475 476 if (pages) { 477 for (i = 0; i < n_pages; i++) { 478 if (s->async_dma_dir != DMA_NONE) { 479 async->buf_page_list[i].virt_addr = 480 dma_alloc_coherent(dev->hw_dev, 481 PAGE_SIZE, 482 &async-> 483 buf_page_list 484 [i].dma_addr, 485 GFP_KERNEL | 486 __GFP_COMP); 487 } else { 488 async->buf_page_list[i].virt_addr = 489 (void *) 490 get_zeroed_page(GFP_KERNEL); 491 } 492 if (async->buf_page_list[i].virt_addr == NULL) 493 break; 494 495 set_bit(PG_reserved, 496 &(virt_to_page(async->buf_page_list[i]. 497 virt_addr)->flags)); 498 pages[i] = virt_to_page(async->buf_page_list[i]. 499 virt_addr); 500 } 501 } 502 if (i == n_pages) { 503 async->prealloc_buf = 504#ifdef PAGE_KERNEL_NOCACHE 505 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 506#else 507 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL); 508#endif 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, 521 &(virt_to_page(async-> 522 buf_page_list[i]. 523 virt_addr)->flags)); 524 if (s->async_dma_dir != DMA_NONE) { 525 dma_free_coherent(dev->hw_dev, 526 PAGE_SIZE, 527 async-> 528 buf_page_list 529 [i].virt_addr, 530 async-> 531 buf_page_list 532 [i].dma_addr); 533 } else { 534 free_page((unsigned long) 535 async->buf_page_list 536 [i].virt_addr); 537 } 538 } 539 vfree(async->buf_page_list); 540 async->buf_page_list = NULL; 541 } 542 return -ENOMEM; 543 } 544 async->n_buf_pages = n_pages; 545 } 546 async->prealloc_bufsz = new_size; 547 548 return 0; 549} 550 551/* munging is applied to data by core as it passes between user 552 * and kernel space */ 553static unsigned int comedi_buf_munge(struct comedi_async *async, 554 unsigned int num_bytes) 555{ 556 struct comedi_subdevice *s = async->subdevice; 557 unsigned int count = 0; 558 const unsigned num_sample_bytes = bytes_per_sample(s); 559 560 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 561 async->munge_count += num_bytes; 562 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 563 return num_bytes; 564 } 565 /* don't munge partial samples */ 566 num_bytes -= num_bytes % num_sample_bytes; 567 while (count < num_bytes) { 568 int block_size; 569 570 block_size = num_bytes - count; 571 if (block_size < 0) { 572 printk(KERN_WARNING 573 "%s: %s: bug! block_size is negative\n", 574 __FILE__, __func__); 575 break; 576 } 577 if ((int)(async->munge_ptr + block_size - 578 async->prealloc_bufsz) > 0) 579 block_size = async->prealloc_bufsz - async->munge_ptr; 580 581 s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, 582 block_size, async->munge_chan); 583 584 smp_wmb(); /* barrier insures data is munged in buffer 585 * before munge_count is incremented */ 586 587 async->munge_chan += block_size / num_sample_bytes; 588 async->munge_chan %= async->cmd.chanlist_len; 589 async->munge_count += block_size; 590 async->munge_ptr += block_size; 591 async->munge_ptr %= async->prealloc_bufsz; 592 count += block_size; 593 } 594 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 595 return count; 596} 597 598unsigned int comedi_buf_write_n_available(struct comedi_async *async) 599{ 600 unsigned int free_end; 601 unsigned int nbytes; 602 603 if (async == NULL) 604 return 0; 605 606 free_end = async->buf_read_count + async->prealloc_bufsz; 607 nbytes = free_end - async->buf_write_alloc_count; 608 nbytes -= nbytes % bytes_per_sample(async->subdevice); 609 /* barrier insures the read of buf_read_count in this 610 query occurs before any following writes to the buffer which 611 might be based on the return value from this query. 612 */ 613 smp_mb(); 614 return nbytes; 615} 616 617/* allocates chunk for the writer from free buffer space */ 618unsigned int comedi_buf_write_alloc(struct comedi_async *async, 619 unsigned int nbytes) 620{ 621 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 622 623 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 624 nbytes = free_end - async->buf_write_alloc_count; 625 626 async->buf_write_alloc_count += nbytes; 627 /* barrier insures the read of buf_read_count above occurs before 628 we write data to the write-alloc'ed buffer space */ 629 smp_mb(); 630 return nbytes; 631} 632EXPORT_SYMBOL(comedi_buf_write_alloc); 633 634/* allocates nothing unless it can completely fulfill the request */ 635unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, 636 unsigned int nbytes) 637{ 638 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 639 640 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 641 nbytes = 0; 642 643 async->buf_write_alloc_count += nbytes; 644 /* barrier insures the read of buf_read_count above occurs before 645 we write data to the write-alloc'ed buffer space */ 646 smp_mb(); 647 return nbytes; 648} 649 650/* transfers a chunk from writer to filled buffer space */ 651unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) 652{ 653 if ((int)(async->buf_write_count + nbytes - 654 async->buf_write_alloc_count) > 0) { 655 printk(KERN_INFO "comedi: attempted to write-free more bytes than have been write-allocated.\n"); 656 nbytes = async->buf_write_alloc_count - async->buf_write_count; 657 } 658 async->buf_write_count += nbytes; 659 async->buf_write_ptr += nbytes; 660 comedi_buf_munge(async, async->buf_write_count - async->munge_count); 661 if (async->buf_write_ptr >= async->prealloc_bufsz) 662 async->buf_write_ptr %= async->prealloc_bufsz; 663 664 return nbytes; 665} 666EXPORT_SYMBOL(comedi_buf_write_free); 667 668/* allocates a chunk for the reader from filled (and munged) buffer space */ 669unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) 670{ 671 if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > 672 0) { 673 nbytes = async->munge_count - async->buf_read_alloc_count; 674 } 675 async->buf_read_alloc_count += nbytes; 676 /* barrier insures read of munge_count occurs before we actually read 677 data out of buffer */ 678 smp_rmb(); 679 return nbytes; 680} 681EXPORT_SYMBOL(comedi_buf_read_alloc); 682 683/* transfers control of a chunk from reader to free buffer space */ 684unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) 685{ 686 /* barrier insures data has been read out of 687 * buffer before read count is incremented */ 688 smp_mb(); 689 if ((int)(async->buf_read_count + nbytes - 690 async->buf_read_alloc_count) > 0) { 691 printk(KERN_INFO 692 "comedi: attempted to read-free more bytes than have been read-allocated.\n"); 693 nbytes = async->buf_read_alloc_count - async->buf_read_count; 694 } 695 async->buf_read_count += nbytes; 696 async->buf_read_ptr += nbytes; 697 async->buf_read_ptr %= async->prealloc_bufsz; 698 return nbytes; 699} 700EXPORT_SYMBOL(comedi_buf_read_free); 701 702void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, 703 const void *data, unsigned int num_bytes) 704{ 705 unsigned int write_ptr = async->buf_write_ptr + offset; 706 707 if (write_ptr >= async->prealloc_bufsz) 708 write_ptr %= async->prealloc_bufsz; 709 710 while (num_bytes) { 711 unsigned int block_size; 712 713 if (write_ptr + num_bytes > async->prealloc_bufsz) 714 block_size = async->prealloc_bufsz - write_ptr; 715 else 716 block_size = num_bytes; 717 718 memcpy(async->prealloc_buf + write_ptr, data, block_size); 719 720 data += block_size; 721 num_bytes -= block_size; 722 723 write_ptr = 0; 724 } 725} 726EXPORT_SYMBOL(comedi_buf_memcpy_to); 727 728void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, 729 void *dest, unsigned int nbytes) 730{ 731 void *src; 732 unsigned int read_ptr = async->buf_read_ptr + offset; 733 734 if (read_ptr >= async->prealloc_bufsz) 735 read_ptr %= async->prealloc_bufsz; 736 737 while (nbytes) { 738 unsigned int block_size; 739 740 src = async->prealloc_buf + read_ptr; 741 742 if (nbytes >= async->prealloc_bufsz - read_ptr) 743 block_size = async->prealloc_bufsz - read_ptr; 744 else 745 block_size = nbytes; 746 747 memcpy(dest, src, block_size); 748 nbytes -= block_size; 749 dest += block_size; 750 read_ptr = 0; 751 } 752} 753EXPORT_SYMBOL(comedi_buf_memcpy_from); 754 755unsigned int comedi_buf_read_n_available(struct comedi_async *async) 756{ 757 unsigned num_bytes; 758 759 if (async == NULL) 760 return 0; 761 num_bytes = async->munge_count - async->buf_read_count; 762 /* barrier insures the read of munge_count in this 763 query occurs before any following reads of the buffer which 764 might be based on the return value from this query. 765 */ 766 smp_rmb(); 767 return num_bytes; 768} 769EXPORT_SYMBOL(comedi_buf_read_n_available); 770 771int comedi_buf_get(struct comedi_async *async, short *x) 772{ 773 unsigned int n = comedi_buf_read_n_available(async); 774 775 if (n < sizeof(short)) 776 return 0; 777 comedi_buf_read_alloc(async, sizeof(short)); 778 *x = *(short *)(async->prealloc_buf + async->buf_read_ptr); 779 comedi_buf_read_free(async, sizeof(short)); 780 return 1; 781} 782EXPORT_SYMBOL(comedi_buf_get); 783 784int comedi_buf_put(struct comedi_async *async, short x) 785{ 786 unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); 787 788 if (n < sizeof(short)) { 789 async->events |= COMEDI_CB_ERROR; 790 return 0; 791 } 792 *(short *)(async->prealloc_buf + async->buf_write_ptr) = x; 793 comedi_buf_write_free(async, sizeof(short)); 794 return 1; 795} 796EXPORT_SYMBOL(comedi_buf_put); 797 798void comedi_reset_async_buf(struct comedi_async *async) 799{ 800 async->buf_write_alloc_count = 0; 801 async->buf_write_count = 0; 802 async->buf_read_alloc_count = 0; 803 async->buf_read_count = 0; 804 805 async->buf_write_ptr = 0; 806 async->buf_read_ptr = 0; 807 808 async->cur_chan = 0; 809 async->scan_progress = 0; 810 async->munge_chan = 0; 811 async->munge_count = 0; 812 async->munge_ptr = 0; 813 814 async->events = 0; 815} 816 817static int comedi_auto_config(struct device *hardware_device, 818 const char *board_name, const int *options, 819 unsigned num_options) 820{ 821 struct comedi_devconfig it; 822 int minor; 823 struct comedi_device_file_info *dev_file_info; 824 int retval; 825 unsigned *private_data = NULL; 826 827 if (!comedi_autoconfig) { 828 dev_set_drvdata(hardware_device, NULL); 829 return 0; 830 } 831 832 minor = comedi_alloc_board_minor(hardware_device); 833 if (minor < 0) 834 return minor; 835 836 private_data = kmalloc(sizeof(unsigned), GFP_KERNEL); 837 if (private_data == NULL) { 838 retval = -ENOMEM; 839 goto cleanup; 840 } 841 *private_data = minor; 842 dev_set_drvdata(hardware_device, private_data); 843 844 dev_file_info = comedi_get_device_file_info(minor); 845 846 memset(&it, 0, sizeof(it)); 847 strncpy(it.board_name, board_name, COMEDI_NAMELEN); 848 it.board_name[COMEDI_NAMELEN - 1] = '\0'; 849 BUG_ON(num_options > COMEDI_NDEVCONFOPTS); 850 memcpy(it.options, options, num_options * sizeof(int)); 851 852 mutex_lock(&dev_file_info->device->mutex); 853 retval = comedi_device_attach(dev_file_info->device, &it); 854 mutex_unlock(&dev_file_info->device->mutex); 855 856cleanup: 857 if (retval < 0) { 858 kfree(private_data); 859 comedi_free_board_minor(minor); 860 } 861 return retval; 862} 863 864static void comedi_auto_unconfig(struct device *hardware_device) 865{ 866 unsigned *minor = (unsigned *)dev_get_drvdata(hardware_device); 867 if (minor == NULL) 868 return; 869 870 BUG_ON(*minor >= COMEDI_NUM_BOARD_MINORS); 871 872 comedi_free_board_minor(*minor); 873 dev_set_drvdata(hardware_device, NULL); 874 kfree(minor); 875} 876 877int comedi_pci_auto_config(struct pci_dev *pcidev, const char *board_name) 878{ 879 int options[2]; 880 881 /* pci bus */ 882 options[0] = pcidev->bus->number; 883 /* pci slot */ 884 options[1] = PCI_SLOT(pcidev->devfn); 885 886 return comedi_auto_config(&pcidev->dev, board_name, 887 options, ARRAY_SIZE(options)); 888} 889EXPORT_SYMBOL_GPL(comedi_pci_auto_config); 890 891void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 892{ 893 comedi_auto_unconfig(&pcidev->dev); 894} 895EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); 896 897int comedi_usb_auto_config(struct usb_device *usbdev, const char *board_name) 898{ 899 BUG_ON(usbdev == NULL); 900 return comedi_auto_config(&usbdev->dev, board_name, NULL, 0); 901} 902EXPORT_SYMBOL_GPL(comedi_usb_auto_config); 903 904void comedi_usb_auto_unconfig(struct usb_device *usbdev) 905{ 906 BUG_ON(usbdev == NULL); 907 comedi_auto_unconfig(&usbdev->dev); 908} 909EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig); 910