drivers.c revision 4e2f002f7a9b316640eb06ef6df767f017e3e7b1
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} 108 109/* do a little post-config cleanup */ 110/* called with module refcount incremented, decrements it */ 111static int comedi_device_postconfig(struct comedi_device *dev) 112{ 113 int ret = postconfig(dev); 114 module_put(dev->driver->module); 115 if (ret < 0) { 116 __comedi_device_detach(dev); 117 return ret; 118 } 119 if (!dev->board_name) { 120 printk(KERN_WARNING "BUG: dev->board_name=<%p>\n", 121 dev->board_name); 122 dev->board_name = "BUG"; 123 } 124 smp_wmb(); 125 dev->attached = 1; 126 return 0; 127} 128 129int comedi_device_attach(struct comedi_device *dev, struct comedi_devconfig *it) 130{ 131 struct comedi_driver *driv; 132 int ret; 133 134 if (dev->attached) 135 return -EBUSY; 136 137 for (driv = comedi_drivers; driv; driv = driv->next) { 138 if (!try_module_get(driv->module)) { 139 printk(KERN_INFO "comedi: failed to increment module count, skipping\n"); 140 continue; 141 } 142 if (driv->num_names) { 143 dev->board_ptr = comedi_recognize(driv, it->board_name); 144 if (dev->board_ptr) 145 break; 146 } else if (strcmp(driv->driver_name, it->board_name)) 147 break; 148 module_put(driv->module); 149 } 150 if (driv == NULL) { 151 /* recognize has failed if we get here */ 152 /* report valid board names before returning error */ 153 for (driv = comedi_drivers; driv; driv = driv->next) { 154 if (!try_module_get(driv->module)) { 155 printk(KERN_INFO 156 "comedi: failed to increment module count\n"); 157 continue; 158 } 159 comedi_report_boards(driv); 160 module_put(driv->module); 161 } 162 return -EIO; 163 } 164 /* initialize dev->driver here so 165 * comedi_error() can be called from attach */ 166 dev->driver = driv; 167 ret = driv->attach(dev, it); 168 if (ret < 0) { 169 module_put(dev->driver->module); 170 __comedi_device_detach(dev); 171 return ret; 172 } 173 return comedi_device_postconfig(dev); 174} 175 176int comedi_driver_register(struct comedi_driver *driver) 177{ 178 driver->next = comedi_drivers; 179 comedi_drivers = driver; 180 181 return 0; 182} 183EXPORT_SYMBOL(comedi_driver_register); 184 185int comedi_driver_unregister(struct comedi_driver *driver) 186{ 187 struct comedi_driver *prev; 188 int i; 189 190 /* check for devices using this driver */ 191 for (i = 0; i < COMEDI_NUM_BOARD_MINORS; i++) { 192 struct comedi_device_file_info *dev_file_info = 193 comedi_get_device_file_info(i); 194 struct comedi_device *dev; 195 196 if (dev_file_info == NULL) 197 continue; 198 dev = dev_file_info->device; 199 200 mutex_lock(&dev->mutex); 201 if (dev->attached && dev->driver == driver) { 202 if (dev->use_count) 203 printk(KERN_WARNING "BUG! detaching device with use_count=%d\n", 204 dev->use_count); 205 comedi_device_detach(dev); 206 } 207 mutex_unlock(&dev->mutex); 208 } 209 210 if (comedi_drivers == driver) { 211 comedi_drivers = driver->next; 212 return 0; 213 } 214 215 for (prev = comedi_drivers; prev->next; prev = prev->next) { 216 if (prev->next == driver) { 217 prev->next = driver->next; 218 return 0; 219 } 220 } 221 return -EINVAL; 222} 223EXPORT_SYMBOL(comedi_driver_unregister); 224 225static int postconfig(struct comedi_device *dev) 226{ 227 int i; 228 struct comedi_subdevice *s; 229 struct comedi_async *async = NULL; 230 int ret; 231 232 for (i = 0; i < dev->n_subdevices; i++) { 233 s = dev->subdevices + i; 234 235 if (s->type == COMEDI_SUBD_UNUSED) 236 continue; 237 238 if (s->len_chanlist == 0) 239 s->len_chanlist = 1; 240 241 if (s->do_cmd) { 242 unsigned int buf_size; 243 244 BUG_ON((s->subdev_flags & (SDF_CMD_READ | 245 SDF_CMD_WRITE)) == 0); 246 BUG_ON(!s->do_cmdtest); 247 248 async = 249 kzalloc(sizeof(struct comedi_async), GFP_KERNEL); 250 if (async == NULL) { 251 printk(KERN_INFO 252 "failed to allocate async struct\n"); 253 return -ENOMEM; 254 } 255 init_waitqueue_head(&async->wait_head); 256 async->subdevice = s; 257 s->async = async; 258 259 async->max_bufsize = 260 comedi_default_buf_maxsize_kb * 1024; 261 buf_size = comedi_default_buf_size_kb * 1024; 262 if (buf_size > async->max_bufsize) 263 buf_size = async->max_bufsize; 264 265 async->prealloc_buf = NULL; 266 async->prealloc_bufsz = 0; 267 if (comedi_buf_alloc(dev, s, 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, 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/* 304 * Generic recognize function for drivers that register their supported 305 * board names. 306 * 307 * 'driv->board_name' points to a 'const char *' member within the 308 * zeroth element of an array of some private board information 309 * structure, say 'struct foo_board' containing a member 'const char 310 * *board_name' that is initialized to point to a board name string that 311 * is one of the candidates matched against this function's 'name' 312 * parameter. 313 * 314 * 'driv->offset' is the size of the private board information 315 * structure, say 'sizeof(struct foo_board)', and 'driv->num_names' is 316 * the length of the array of private board information structures. 317 * 318 * If one of the board names in the array of private board information 319 * structures matches the name supplied to this function, the function 320 * returns a pointer to the pointer to the board name, otherwise it 321 * returns NULL. The return value ends up in the 'board_ptr' member of 322 * a 'struct comedi_device' that the low-level comedi driver's 323 * 'attach()' hook can convert to a point to a particular element of its 324 * array of private board information structures by subtracting the 325 * offset of the member that points to the board name. (No subtraction 326 * is required if the board name pointer is the first member of the 327 * private board information structure, which is generally the case.) 328 */ 329static void *comedi_recognize(struct comedi_driver *driv, const char *name) 330{ 331 char **name_ptr = (char **)driv->board_name; 332 int i; 333 334 for (i = 0; i < driv->num_names; i++) { 335 if (strcmp(*name_ptr, name) == 0) 336 return name_ptr; 337 name_ptr = (void *)name_ptr + driv->offset; 338 } 339 340 return NULL; 341} 342 343static void comedi_report_boards(struct comedi_driver *driv) 344{ 345 unsigned int i; 346 const char *const *name_ptr; 347 348 printk(KERN_INFO "comedi: valid board names for %s driver are:\n", 349 driv->driver_name); 350 351 name_ptr = driv->board_name; 352 for (i = 0; i < driv->num_names; i++) { 353 printk(KERN_INFO " %s\n", *name_ptr); 354 name_ptr = (const char **)((char *)name_ptr + driv->offset); 355 } 356 357 if (driv->num_names == 0) 358 printk(KERN_INFO " %s\n", driv->driver_name); 359} 360 361static int poll_invalid(struct comedi_device *dev, struct comedi_subdevice *s) 362{ 363 return -EINVAL; 364} 365 366int insn_inval(struct comedi_device *dev, struct comedi_subdevice *s, 367 struct comedi_insn *insn, unsigned int *data) 368{ 369 return -EINVAL; 370} 371 372static int insn_rw_emulate_bits(struct comedi_device *dev, 373 struct comedi_subdevice *s, 374 struct comedi_insn *insn, unsigned int *data) 375{ 376 struct comedi_insn new_insn; 377 int ret; 378 static const unsigned channels_per_bitfield = 32; 379 380 unsigned chan = CR_CHAN(insn->chanspec); 381 const unsigned base_bitfield_channel = 382 (chan < channels_per_bitfield) ? 0 : chan; 383 unsigned int new_data[2]; 384 memset(new_data, 0, sizeof(new_data)); 385 memset(&new_insn, 0, sizeof(new_insn)); 386 new_insn.insn = INSN_BITS; 387 new_insn.chanspec = base_bitfield_channel; 388 new_insn.n = 2; 389 new_insn.data = new_data; 390 new_insn.subdev = insn->subdev; 391 392 if (insn->insn == INSN_WRITE) { 393 if (!(s->subdev_flags & SDF_WRITABLE)) 394 return -EINVAL; 395 new_data[0] = 1 << (chan - base_bitfield_channel); /* mask */ 396 new_data[1] = data[0] ? (1 << (chan - base_bitfield_channel)) 397 : 0; /* bits */ 398 } 399 400 ret = s->insn_bits(dev, s, &new_insn, new_data); 401 if (ret < 0) 402 return ret; 403 404 if (insn->insn == INSN_READ) 405 data[0] = (new_data[1] >> (chan - base_bitfield_channel)) & 1; 406 407 return 1; 408} 409 410int comedi_buf_alloc(struct comedi_device *dev, struct comedi_subdevice *s, 411 unsigned long new_size) 412{ 413 struct comedi_async *async = s->async; 414 415 /* Round up new_size to multiple of PAGE_SIZE */ 416 new_size = (new_size + PAGE_SIZE - 1) & PAGE_MASK; 417 418 /* if no change is required, do nothing */ 419 if (async->prealloc_buf && async->prealloc_bufsz == new_size) 420 return 0; 421 422 /* deallocate old buffer */ 423 if (async->prealloc_buf) { 424 vunmap(async->prealloc_buf); 425 async->prealloc_buf = NULL; 426 async->prealloc_bufsz = 0; 427 } 428 if (async->buf_page_list) { 429 unsigned i; 430 for (i = 0; i < async->n_buf_pages; ++i) { 431 if (async->buf_page_list[i].virt_addr) { 432 clear_bit(PG_reserved, 433 &(virt_to_page(async->buf_page_list[i]. 434 virt_addr)->flags)); 435 if (s->async_dma_dir != DMA_NONE) { 436 dma_free_coherent(dev->hw_dev, 437 PAGE_SIZE, 438 async-> 439 buf_page_list 440 [i].virt_addr, 441 async-> 442 buf_page_list 443 [i].dma_addr); 444 } else { 445 free_page((unsigned long) 446 async->buf_page_list[i]. 447 virt_addr); 448 } 449 } 450 } 451 vfree(async->buf_page_list); 452 async->buf_page_list = NULL; 453 async->n_buf_pages = 0; 454 } 455 /* allocate new buffer */ 456 if (new_size) { 457 unsigned i = 0; 458 unsigned n_pages = new_size >> PAGE_SHIFT; 459 struct page **pages = NULL; 460 461 async->buf_page_list = 462 vzalloc(sizeof(struct comedi_buf_page) * n_pages); 463 if (async->buf_page_list) 464 pages = vmalloc(sizeof(struct page *) * n_pages); 465 466 if (pages) { 467 for (i = 0; i < n_pages; i++) { 468 if (s->async_dma_dir != DMA_NONE) { 469 async->buf_page_list[i].virt_addr = 470 dma_alloc_coherent(dev->hw_dev, 471 PAGE_SIZE, 472 &async-> 473 buf_page_list 474 [i].dma_addr, 475 GFP_KERNEL | 476 __GFP_COMP); 477 } else { 478 async->buf_page_list[i].virt_addr = 479 (void *) 480 get_zeroed_page(GFP_KERNEL); 481 } 482 if (async->buf_page_list[i].virt_addr == NULL) 483 break; 484 485 set_bit(PG_reserved, 486 &(virt_to_page(async->buf_page_list[i]. 487 virt_addr)->flags)); 488 pages[i] = virt_to_page(async->buf_page_list[i]. 489 virt_addr); 490 } 491 } 492 if (i == n_pages) { 493 async->prealloc_buf = 494#ifdef PAGE_KERNEL_NOCACHE 495 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL_NOCACHE); 496#else 497 vmap(pages, n_pages, VM_MAP, PAGE_KERNEL); 498#endif 499 } 500 vfree(pages); 501 502 if (async->prealloc_buf == NULL) { 503 /* Some allocation failed above. */ 504 if (async->buf_page_list) { 505 for (i = 0; i < n_pages; i++) { 506 if (async->buf_page_list[i].virt_addr == 507 NULL) { 508 break; 509 } 510 clear_bit(PG_reserved, 511 &(virt_to_page(async-> 512 buf_page_list[i]. 513 virt_addr)->flags)); 514 if (s->async_dma_dir != DMA_NONE) { 515 dma_free_coherent(dev->hw_dev, 516 PAGE_SIZE, 517 async-> 518 buf_page_list 519 [i].virt_addr, 520 async-> 521 buf_page_list 522 [i].dma_addr); 523 } else { 524 free_page((unsigned long) 525 async->buf_page_list 526 [i].virt_addr); 527 } 528 } 529 vfree(async->buf_page_list); 530 async->buf_page_list = NULL; 531 } 532 return -ENOMEM; 533 } 534 async->n_buf_pages = n_pages; 535 } 536 async->prealloc_bufsz = new_size; 537 538 return 0; 539} 540 541/* munging is applied to data by core as it passes between user 542 * and kernel space */ 543static unsigned int comedi_buf_munge(struct comedi_async *async, 544 unsigned int num_bytes) 545{ 546 struct comedi_subdevice *s = async->subdevice; 547 unsigned int count = 0; 548 const unsigned num_sample_bytes = bytes_per_sample(s); 549 550 if (s->munge == NULL || (async->cmd.flags & CMDF_RAWDATA)) { 551 async->munge_count += num_bytes; 552 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 553 return num_bytes; 554 } 555 /* don't munge partial samples */ 556 num_bytes -= num_bytes % num_sample_bytes; 557 while (count < num_bytes) { 558 int block_size; 559 560 block_size = num_bytes - count; 561 if (block_size < 0) { 562 printk(KERN_WARNING 563 "%s: %s: bug! block_size is negative\n", 564 __FILE__, __func__); 565 break; 566 } 567 if ((int)(async->munge_ptr + block_size - 568 async->prealloc_bufsz) > 0) 569 block_size = async->prealloc_bufsz - async->munge_ptr; 570 571 s->munge(s->device, s, async->prealloc_buf + async->munge_ptr, 572 block_size, async->munge_chan); 573 574 smp_wmb(); /* barrier insures data is munged in buffer 575 * before munge_count is incremented */ 576 577 async->munge_chan += block_size / num_sample_bytes; 578 async->munge_chan %= async->cmd.chanlist_len; 579 async->munge_count += block_size; 580 async->munge_ptr += block_size; 581 async->munge_ptr %= async->prealloc_bufsz; 582 count += block_size; 583 } 584 BUG_ON((int)(async->munge_count - async->buf_write_count) > 0); 585 return count; 586} 587 588unsigned int comedi_buf_write_n_available(struct comedi_async *async) 589{ 590 unsigned int free_end; 591 unsigned int nbytes; 592 593 if (async == NULL) 594 return 0; 595 596 free_end = async->buf_read_count + async->prealloc_bufsz; 597 nbytes = free_end - async->buf_write_alloc_count; 598 nbytes -= nbytes % bytes_per_sample(async->subdevice); 599 /* barrier insures the read of buf_read_count in this 600 query occurs before any following writes to the buffer which 601 might be based on the return value from this query. 602 */ 603 smp_mb(); 604 return nbytes; 605} 606 607/* allocates chunk for the writer from free buffer space */ 608unsigned int comedi_buf_write_alloc(struct comedi_async *async, 609 unsigned int nbytes) 610{ 611 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 612 613 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 614 nbytes = free_end - async->buf_write_alloc_count; 615 616 async->buf_write_alloc_count += nbytes; 617 /* barrier insures the read of buf_read_count above occurs before 618 we write data to the write-alloc'ed buffer space */ 619 smp_mb(); 620 return nbytes; 621} 622EXPORT_SYMBOL(comedi_buf_write_alloc); 623 624/* allocates nothing unless it can completely fulfill the request */ 625unsigned int comedi_buf_write_alloc_strict(struct comedi_async *async, 626 unsigned int nbytes) 627{ 628 unsigned int free_end = async->buf_read_count + async->prealloc_bufsz; 629 630 if ((int)(async->buf_write_alloc_count + nbytes - free_end) > 0) 631 nbytes = 0; 632 633 async->buf_write_alloc_count += nbytes; 634 /* barrier insures the read of buf_read_count above occurs before 635 we write data to the write-alloc'ed buffer space */ 636 smp_mb(); 637 return nbytes; 638} 639 640/* transfers a chunk from writer to filled buffer space */ 641unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) 642{ 643 if ((int)(async->buf_write_count + nbytes - 644 async->buf_write_alloc_count) > 0) { 645 printk(KERN_INFO "comedi: attempted to write-free more bytes than have been write-allocated.\n"); 646 nbytes = async->buf_write_alloc_count - async->buf_write_count; 647 } 648 async->buf_write_count += nbytes; 649 async->buf_write_ptr += nbytes; 650 comedi_buf_munge(async, async->buf_write_count - async->munge_count); 651 if (async->buf_write_ptr >= async->prealloc_bufsz) 652 async->buf_write_ptr %= async->prealloc_bufsz; 653 654 return nbytes; 655} 656EXPORT_SYMBOL(comedi_buf_write_free); 657 658/* allocates a chunk for the reader from filled (and munged) buffer space */ 659unsigned comedi_buf_read_alloc(struct comedi_async *async, unsigned nbytes) 660{ 661 if ((int)(async->buf_read_alloc_count + nbytes - async->munge_count) > 662 0) { 663 nbytes = async->munge_count - async->buf_read_alloc_count; 664 } 665 async->buf_read_alloc_count += nbytes; 666 /* barrier insures read of munge_count occurs before we actually read 667 data out of buffer */ 668 smp_rmb(); 669 return nbytes; 670} 671EXPORT_SYMBOL(comedi_buf_read_alloc); 672 673/* transfers control of a chunk from reader to free buffer space */ 674unsigned comedi_buf_read_free(struct comedi_async *async, unsigned int nbytes) 675{ 676 /* barrier insures data has been read out of 677 * buffer before read count is incremented */ 678 smp_mb(); 679 if ((int)(async->buf_read_count + nbytes - 680 async->buf_read_alloc_count) > 0) { 681 printk(KERN_INFO 682 "comedi: attempted to read-free more bytes than have been read-allocated.\n"); 683 nbytes = async->buf_read_alloc_count - async->buf_read_count; 684 } 685 async->buf_read_count += nbytes; 686 async->buf_read_ptr += nbytes; 687 async->buf_read_ptr %= async->prealloc_bufsz; 688 return nbytes; 689} 690EXPORT_SYMBOL(comedi_buf_read_free); 691 692void comedi_buf_memcpy_to(struct comedi_async *async, unsigned int offset, 693 const void *data, unsigned int num_bytes) 694{ 695 unsigned int write_ptr = async->buf_write_ptr + offset; 696 697 if (write_ptr >= async->prealloc_bufsz) 698 write_ptr %= async->prealloc_bufsz; 699 700 while (num_bytes) { 701 unsigned int block_size; 702 703 if (write_ptr + num_bytes > async->prealloc_bufsz) 704 block_size = async->prealloc_bufsz - write_ptr; 705 else 706 block_size = num_bytes; 707 708 memcpy(async->prealloc_buf + write_ptr, data, block_size); 709 710 data += block_size; 711 num_bytes -= block_size; 712 713 write_ptr = 0; 714 } 715} 716EXPORT_SYMBOL(comedi_buf_memcpy_to); 717 718void comedi_buf_memcpy_from(struct comedi_async *async, unsigned int offset, 719 void *dest, unsigned int nbytes) 720{ 721 void *src; 722 unsigned int read_ptr = async->buf_read_ptr + offset; 723 724 if (read_ptr >= async->prealloc_bufsz) 725 read_ptr %= async->prealloc_bufsz; 726 727 while (nbytes) { 728 unsigned int block_size; 729 730 src = async->prealloc_buf + read_ptr; 731 732 if (nbytes >= async->prealloc_bufsz - read_ptr) 733 block_size = async->prealloc_bufsz - read_ptr; 734 else 735 block_size = nbytes; 736 737 memcpy(dest, src, block_size); 738 nbytes -= block_size; 739 dest += block_size; 740 read_ptr = 0; 741 } 742} 743EXPORT_SYMBOL(comedi_buf_memcpy_from); 744 745unsigned int comedi_buf_read_n_available(struct comedi_async *async) 746{ 747 unsigned num_bytes; 748 749 if (async == NULL) 750 return 0; 751 num_bytes = async->munge_count - async->buf_read_count; 752 /* barrier insures the read of munge_count in this 753 query occurs before any following reads of the buffer which 754 might be based on the return value from this query. 755 */ 756 smp_rmb(); 757 return num_bytes; 758} 759EXPORT_SYMBOL(comedi_buf_read_n_available); 760 761int comedi_buf_get(struct comedi_async *async, short *x) 762{ 763 unsigned int n = comedi_buf_read_n_available(async); 764 765 if (n < sizeof(short)) 766 return 0; 767 comedi_buf_read_alloc(async, sizeof(short)); 768 *x = *(short *)(async->prealloc_buf + async->buf_read_ptr); 769 comedi_buf_read_free(async, sizeof(short)); 770 return 1; 771} 772EXPORT_SYMBOL(comedi_buf_get); 773 774int comedi_buf_put(struct comedi_async *async, short x) 775{ 776 unsigned int n = comedi_buf_write_alloc_strict(async, sizeof(short)); 777 778 if (n < sizeof(short)) { 779 async->events |= COMEDI_CB_ERROR; 780 return 0; 781 } 782 *(short *)(async->prealloc_buf + async->buf_write_ptr) = x; 783 comedi_buf_write_free(async, sizeof(short)); 784 return 1; 785} 786EXPORT_SYMBOL(comedi_buf_put); 787 788void comedi_reset_async_buf(struct comedi_async *async) 789{ 790 async->buf_write_alloc_count = 0; 791 async->buf_write_count = 0; 792 async->buf_read_alloc_count = 0; 793 async->buf_read_count = 0; 794 795 async->buf_write_ptr = 0; 796 async->buf_read_ptr = 0; 797 798 async->cur_chan = 0; 799 async->scan_progress = 0; 800 async->munge_chan = 0; 801 async->munge_count = 0; 802 async->munge_ptr = 0; 803 804 async->events = 0; 805} 806 807static int 808comedi_auto_config_helper(struct device *hardware_device, 809 struct comedi_driver *driver, 810 int (*attach_wrapper) (struct comedi_device *, 811 void *), void *context) 812{ 813 int minor; 814 struct comedi_device_file_info *dev_file_info; 815 struct comedi_device *comedi_dev; 816 int ret; 817 818 if (!comedi_autoconfig) 819 return 0; 820 821 minor = comedi_alloc_board_minor(hardware_device); 822 if (minor < 0) 823 return minor; 824 825 dev_file_info = comedi_get_device_file_info(minor); 826 comedi_dev = dev_file_info->device; 827 828 mutex_lock(&comedi_dev->mutex); 829 if (comedi_dev->attached) 830 ret = -EBUSY; 831 else if (!try_module_get(driver->module)) { 832 printk(KERN_INFO "comedi: failed to increment module count\n"); 833 ret = -EIO; 834 } else { 835 /* set comedi_dev->driver here for attach wrapper */ 836 comedi_dev->driver = driver; 837 ret = (*attach_wrapper)(comedi_dev, context); 838 if (ret < 0) { 839 module_put(driver->module); 840 __comedi_device_detach(comedi_dev); 841 } else { 842 ret = comedi_device_postconfig(comedi_dev); 843 } 844 } 845 mutex_unlock(&comedi_dev->mutex); 846 847 if (ret < 0) 848 comedi_free_board_minor(minor); 849 return ret; 850} 851 852static int comedi_auto_config_wrapper(struct comedi_device *dev, void *context) 853{ 854 struct comedi_devconfig *it = context; 855 struct comedi_driver *driv = dev->driver; 856 857 if (driv->num_names) { 858 /* look for generic board entry matching driver name, which 859 * has already been copied to it->board_name */ 860 dev->board_ptr = comedi_recognize(driv, it->board_name); 861 if (dev->board_ptr == NULL) { 862 printk(KERN_WARNING 863 "comedi: auto config failed to find board entry" 864 " '%s' for driver '%s'\n", it->board_name, 865 driv->driver_name); 866 comedi_report_boards(driv); 867 return -EINVAL; 868 } 869 } 870 return driv->attach(dev, it); 871} 872 873static int comedi_auto_config(struct device *hardware_device, 874 struct comedi_driver *driver, const int *options, 875 unsigned num_options) 876{ 877 struct comedi_devconfig it; 878 879 memset(&it, 0, sizeof(it)); 880 strncpy(it.board_name, driver->driver_name, COMEDI_NAMELEN); 881 it.board_name[COMEDI_NAMELEN - 1] = '\0'; 882 BUG_ON(num_options > COMEDI_NDEVCONFOPTS); 883 memcpy(it.options, options, num_options * sizeof(int)); 884 return comedi_auto_config_helper(hardware_device, driver, 885 comedi_auto_config_wrapper, &it); 886} 887 888static void comedi_auto_unconfig(struct device *hardware_device) 889{ 890 int minor; 891 892 if (hardware_device == NULL) 893 return; 894 minor = comedi_find_board_minor(hardware_device); 895 if (minor < 0) 896 return; 897 BUG_ON(minor >= COMEDI_NUM_BOARD_MINORS); 898 comedi_free_board_minor(minor); 899} 900 901/** 902 * comedi_pci_enable() - Enable the PCI device and request the regions. 903 * @pdev: pci_dev struct 904 * @res_name: name for the requested reqource 905 */ 906int comedi_pci_enable(struct pci_dev *pdev, const char *res_name) 907{ 908 int rc; 909 910 rc = pci_enable_device(pdev); 911 if (rc < 0) 912 return rc; 913 914 rc = pci_request_regions(pdev, res_name); 915 if (rc < 0) 916 pci_disable_device(pdev); 917 918 return rc; 919} 920EXPORT_SYMBOL_GPL(comedi_pci_enable); 921 922/** 923 * comedi_pci_disable() - Release the regions and disable the PCI device. 924 * @pdev: pci_dev struct 925 * 926 * This must be matched with a previous successful call to comedi_pci_enable(). 927 */ 928void comedi_pci_disable(struct pci_dev *pdev) 929{ 930 pci_release_regions(pdev); 931 pci_disable_device(pdev); 932} 933EXPORT_SYMBOL_GPL(comedi_pci_disable); 934 935static int comedi_old_pci_auto_config(struct pci_dev *pcidev, 936 struct comedi_driver *driver) 937{ 938 int options[2]; 939 940 /* pci bus */ 941 options[0] = pcidev->bus->number; 942 /* pci slot */ 943 options[1] = PCI_SLOT(pcidev->devfn); 944 945 return comedi_auto_config(&pcidev->dev, driver, 946 options, ARRAY_SIZE(options)); 947} 948 949static int comedi_pci_attach_wrapper(struct comedi_device *dev, void *pcidev) 950{ 951 return dev->driver->attach_pci(dev, pcidev); 952} 953 954static int comedi_new_pci_auto_config(struct pci_dev *pcidev, 955 struct comedi_driver *driver) 956{ 957 return comedi_auto_config_helper(&pcidev->dev, driver, 958 comedi_pci_attach_wrapper, pcidev); 959} 960 961int comedi_pci_auto_config(struct pci_dev *pcidev, struct comedi_driver *driver) 962{ 963 964 if (driver->attach_pci) 965 return comedi_new_pci_auto_config(pcidev, driver); 966 else 967 return comedi_old_pci_auto_config(pcidev, driver); 968} 969EXPORT_SYMBOL_GPL(comedi_pci_auto_config); 970 971void comedi_pci_auto_unconfig(struct pci_dev *pcidev) 972{ 973 comedi_auto_unconfig(&pcidev->dev); 974} 975EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); 976 977int comedi_pci_driver_register(struct comedi_driver *comedi_driver, 978 struct pci_driver *pci_driver) 979{ 980 int ret; 981 982 ret = comedi_driver_register(comedi_driver); 983 if (ret < 0) 984 return ret; 985 986 /* FIXME: Remove this test after auditing all comedi pci drivers */ 987 if (!pci_driver->name) 988 pci_driver->name = comedi_driver->driver_name; 989 990 ret = pci_register_driver(pci_driver); 991 if (ret < 0) { 992 comedi_driver_unregister(comedi_driver); 993 return ret; 994 } 995 996 return 0; 997} 998EXPORT_SYMBOL_GPL(comedi_pci_driver_register); 999 1000void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver, 1001 struct pci_driver *pci_driver) 1002{ 1003 pci_unregister_driver(pci_driver); 1004 comedi_driver_unregister(comedi_driver); 1005} 1006EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister); 1007 1008static int comedi_old_usb_auto_config(struct usb_interface *intf, 1009 struct comedi_driver *driver) 1010{ 1011 return comedi_auto_config(&intf->dev, driver, NULL, 0); 1012} 1013 1014static int comedi_usb_attach_wrapper(struct comedi_device *dev, void *intf) 1015{ 1016 return dev->driver->attach_usb(dev, intf); 1017} 1018 1019static int comedi_new_usb_auto_config(struct usb_interface *intf, 1020 struct comedi_driver *driver) 1021{ 1022 return comedi_auto_config_helper(&intf->dev, driver, 1023 comedi_usb_attach_wrapper, intf); 1024} 1025 1026int comedi_usb_auto_config(struct usb_interface *intf, 1027 struct comedi_driver *driver) 1028{ 1029 BUG_ON(intf == NULL); 1030 if (driver->attach_usb) 1031 return comedi_new_usb_auto_config(intf, driver); 1032 else 1033 return comedi_old_usb_auto_config(intf, driver); 1034} 1035EXPORT_SYMBOL_GPL(comedi_usb_auto_config); 1036 1037void comedi_usb_auto_unconfig(struct usb_interface *intf) 1038{ 1039 BUG_ON(intf == NULL); 1040 comedi_auto_unconfig(&intf->dev); 1041} 1042EXPORT_SYMBOL_GPL(comedi_usb_auto_unconfig); 1043 1044int comedi_usb_driver_register(struct comedi_driver *comedi_driver, 1045 struct usb_driver *usb_driver) 1046{ 1047 int ret; 1048 1049 ret = comedi_driver_register(comedi_driver); 1050 if (ret < 0) 1051 return ret; 1052 1053 ret = usb_register(usb_driver); 1054 if (ret < 0) { 1055 comedi_driver_unregister(comedi_driver); 1056 return ret; 1057 } 1058 1059 return 0; 1060} 1061EXPORT_SYMBOL_GPL(comedi_usb_driver_register); 1062 1063void comedi_usb_driver_unregister(struct comedi_driver *comedi_driver, 1064 struct usb_driver *usb_driver) 1065{ 1066 usb_deregister(usb_driver); 1067 comedi_driver_unregister(comedi_driver); 1068} 1069EXPORT_SYMBOL_GPL(comedi_usb_driver_unregister); 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