1 /* 2 * Information interface for ALSA driver 3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz> 4 * 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 */ 21 22 #include <linux/init.h> 23 #include <linux/time.h> 24 #include <linux/mm.h> 25 #include <linux/slab.h> 26 #include <linux/string.h> 27 #include <sound/core.h> 28 #include <sound/minors.h> 29 #include <sound/info.h> 30 #include <sound/version.h> 31 #include <linux/proc_fs.h> 32 #include <linux/mutex.h> 33 #include <stdarg.h> 34 35 /* 36 * 37 */ 38 39 #ifdef CONFIG_PROC_FS 40 41 int snd_info_check_reserved_words(const char *str) 42 { 43 static char *reserved[] = 44 { 45 "version", 46 "meminfo", 47 "memdebug", 48 "detect", 49 "devices", 50 "oss", 51 "cards", 52 "timers", 53 "synth", 54 "pcm", 55 "seq", 56 NULL 57 }; 58 char **xstr = reserved; 59 60 while (*xstr) { 61 if (!strcmp(*xstr, str)) 62 return 0; 63 xstr++; 64 } 65 if (!strncmp(str, "card", 4)) 66 return 0; 67 return 1; 68 } 69 70 static DEFINE_MUTEX(info_mutex); 71 72 struct snd_info_private_data { 73 struct snd_info_buffer *rbuffer; 74 struct snd_info_buffer *wbuffer; 75 struct snd_info_entry *entry; 76 void *file_private_data; 77 }; 78 79 static int snd_info_version_init(void); 80 static int snd_info_version_done(void); 81 static void snd_info_disconnect(struct snd_info_entry *entry); 82 83 84 /* resize the proc r/w buffer */ 85 static int resize_info_buffer(struct snd_info_buffer *buffer, 86 unsigned int nsize) 87 { 88 char *nbuf; 89 90 nsize = PAGE_ALIGN(nsize); 91 nbuf = krealloc(buffer->buffer, nsize, GFP_KERNEL); 92 if (! nbuf) 93 return -ENOMEM; 94 95 buffer->buffer = nbuf; 96 buffer->len = nsize; 97 return 0; 98 } 99 100 /** 101 * snd_iprintf - printf on the procfs buffer 102 * @buffer: the procfs buffer 103 * @fmt: the printf format 104 * 105 * Outputs the string on the procfs buffer just like printf(). 106 * 107 * Returns the size of output string. 108 */ 109 int snd_iprintf(struct snd_info_buffer *buffer, const char *fmt, ...) 110 { 111 va_list args; 112 int len, res; 113 int err = 0; 114 115 might_sleep(); 116 if (buffer->stop || buffer->error) 117 return 0; 118 len = buffer->len - buffer->size; 119 va_start(args, fmt); 120 for (;;) { 121 va_list ap; 122 va_copy(ap, args); 123 res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap); 124 va_end(ap); 125 if (res < len) 126 break; 127 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE); 128 if (err < 0) 129 break; 130 len = buffer->len - buffer->size; 131 } 132 va_end(args); 133 134 if (err < 0) 135 return err; 136 buffer->curr += res; 137 buffer->size += res; 138 return res; 139 } 140 141 EXPORT_SYMBOL(snd_iprintf); 142 143 /* 144 145 */ 146 147 static struct proc_dir_entry *snd_proc_root; 148 struct snd_info_entry *snd_seq_root; 149 EXPORT_SYMBOL(snd_seq_root); 150 151 #ifdef CONFIG_SND_OSSEMUL 152 struct snd_info_entry *snd_oss_root; 153 #endif 154 155 static void snd_remove_proc_entry(struct proc_dir_entry *parent, 156 struct proc_dir_entry *de) 157 { 158 if (de) 159 remove_proc_entry(de->name, parent); 160 } 161 162 static loff_t snd_info_entry_llseek(struct file *file, loff_t offset, int orig) 163 { 164 struct snd_info_private_data *data; 165 struct snd_info_entry *entry; 166 loff_t ret = -EINVAL, size; 167 168 data = file->private_data; 169 entry = data->entry; 170 mutex_lock(&entry->access); 171 if (entry->content == SNDRV_INFO_CONTENT_DATA && 172 entry->c.ops->llseek) { 173 offset = entry->c.ops->llseek(entry, 174 data->file_private_data, 175 file, offset, orig); 176 goto out; 177 } 178 if (entry->content == SNDRV_INFO_CONTENT_DATA) 179 size = entry->size; 180 else 181 size = 0; 182 switch (orig) { 183 case SEEK_SET: 184 break; 185 case SEEK_CUR: 186 offset += file->f_pos; 187 break; 188 case SEEK_END: 189 if (!size) 190 goto out; 191 offset += size; 192 break; 193 default: 194 goto out; 195 } 196 if (offset < 0) 197 goto out; 198 if (size && offset > size) 199 offset = size; 200 file->f_pos = offset; 201 ret = offset; 202 out: 203 mutex_unlock(&entry->access); 204 return ret; 205 } 206 207 static ssize_t snd_info_entry_read(struct file *file, char __user *buffer, 208 size_t count, loff_t * offset) 209 { 210 struct snd_info_private_data *data; 211 struct snd_info_entry *entry; 212 struct snd_info_buffer *buf; 213 size_t size = 0; 214 loff_t pos; 215 216 data = file->private_data; 217 if (snd_BUG_ON(!data)) 218 return -ENXIO; 219 pos = *offset; 220 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0) 221 return -EIO; 222 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos) 223 return -EIO; 224 entry = data->entry; 225 switch (entry->content) { 226 case SNDRV_INFO_CONTENT_TEXT: 227 buf = data->rbuffer; 228 if (buf == NULL) 229 return -EIO; 230 if (pos >= buf->size) 231 return 0; 232 size = buf->size - pos; 233 size = min(count, size); 234 if (copy_to_user(buffer, buf->buffer + pos, size)) 235 return -EFAULT; 236 break; 237 case SNDRV_INFO_CONTENT_DATA: 238 if (pos >= entry->size) 239 return 0; 240 if (entry->c.ops->read) { 241 size = entry->size - pos; 242 size = min(count, size); 243 size = entry->c.ops->read(entry, 244 data->file_private_data, 245 file, buffer, size, pos); 246 } 247 break; 248 } 249 if ((ssize_t) size > 0) 250 *offset = pos + size; 251 return size; 252 } 253 254 static ssize_t snd_info_entry_write(struct file *file, const char __user *buffer, 255 size_t count, loff_t * offset) 256 { 257 struct snd_info_private_data *data; 258 struct snd_info_entry *entry; 259 struct snd_info_buffer *buf; 260 ssize_t size = 0; 261 loff_t pos; 262 263 data = file->private_data; 264 if (snd_BUG_ON(!data)) 265 return -ENXIO; 266 entry = data->entry; 267 pos = *offset; 268 if (pos < 0 || (long) pos != pos || (ssize_t) count < 0) 269 return -EIO; 270 if ((unsigned long) pos + (unsigned long) count < (unsigned long) pos) 271 return -EIO; 272 switch (entry->content) { 273 case SNDRV_INFO_CONTENT_TEXT: 274 buf = data->wbuffer; 275 if (buf == NULL) 276 return -EIO; 277 mutex_lock(&entry->access); 278 if (pos + count >= buf->len) { 279 if (resize_info_buffer(buf, pos + count)) { 280 mutex_unlock(&entry->access); 281 return -ENOMEM; 282 } 283 } 284 if (copy_from_user(buf->buffer + pos, buffer, count)) { 285 mutex_unlock(&entry->access); 286 return -EFAULT; 287 } 288 buf->size = pos + count; 289 mutex_unlock(&entry->access); 290 size = count; 291 break; 292 case SNDRV_INFO_CONTENT_DATA: 293 if (entry->c.ops->write && count > 0) { 294 size_t maxsize = entry->size - pos; 295 count = min(count, maxsize); 296 size = entry->c.ops->write(entry, 297 data->file_private_data, 298 file, buffer, count, pos); 299 } 300 break; 301 } 302 if ((ssize_t) size > 0) 303 *offset = pos + size; 304 return size; 305 } 306 307 static int snd_info_entry_open(struct inode *inode, struct file *file) 308 { 309 struct snd_info_entry *entry; 310 struct snd_info_private_data *data; 311 struct snd_info_buffer *buffer; 312 struct proc_dir_entry *p; 313 int mode, err; 314 315 mutex_lock(&info_mutex); 316 p = PDE(inode); 317 entry = p == NULL ? NULL : (struct snd_info_entry *)p->data; 318 if (entry == NULL || ! entry->p) { 319 mutex_unlock(&info_mutex); 320 return -ENODEV; 321 } 322 if (!try_module_get(entry->module)) { 323 err = -EFAULT; 324 goto __error1; 325 } 326 mode = file->f_flags & O_ACCMODE; 327 if (mode == O_RDONLY || mode == O_RDWR) { 328 if ((entry->content == SNDRV_INFO_CONTENT_DATA && 329 entry->c.ops->read == NULL)) { 330 err = -ENODEV; 331 goto __error; 332 } 333 } 334 if (mode == O_WRONLY || mode == O_RDWR) { 335 if ((entry->content == SNDRV_INFO_CONTENT_DATA && 336 entry->c.ops->write == NULL)) { 337 err = -ENODEV; 338 goto __error; 339 } 340 } 341 data = kzalloc(sizeof(*data), GFP_KERNEL); 342 if (data == NULL) { 343 err = -ENOMEM; 344 goto __error; 345 } 346 data->entry = entry; 347 switch (entry->content) { 348 case SNDRV_INFO_CONTENT_TEXT: 349 if (mode == O_RDONLY || mode == O_RDWR) { 350 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); 351 if (buffer == NULL) 352 goto __nomem; 353 data->rbuffer = buffer; 354 buffer->len = PAGE_SIZE; 355 buffer->buffer = kmalloc(buffer->len, GFP_KERNEL); 356 if (buffer->buffer == NULL) 357 goto __nomem; 358 } 359 if (mode == O_WRONLY || mode == O_RDWR) { 360 buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); 361 if (buffer == NULL) 362 goto __nomem; 363 data->wbuffer = buffer; 364 buffer->len = PAGE_SIZE; 365 buffer->buffer = kmalloc(buffer->len, GFP_KERNEL); 366 if (buffer->buffer == NULL) 367 goto __nomem; 368 } 369 break; 370 case SNDRV_INFO_CONTENT_DATA: /* data */ 371 if (entry->c.ops->open) { 372 if ((err = entry->c.ops->open(entry, mode, 373 &data->file_private_data)) < 0) { 374 kfree(data); 375 goto __error; 376 } 377 } 378 break; 379 } 380 file->private_data = data; 381 mutex_unlock(&info_mutex); 382 if (entry->content == SNDRV_INFO_CONTENT_TEXT && 383 (mode == O_RDONLY || mode == O_RDWR)) { 384 if (entry->c.text.read) { 385 mutex_lock(&entry->access); 386 entry->c.text.read(entry, data->rbuffer); 387 mutex_unlock(&entry->access); 388 } 389 } 390 return 0; 391 392 __nomem: 393 if (data->rbuffer) { 394 kfree(data->rbuffer->buffer); 395 kfree(data->rbuffer); 396 } 397 if (data->wbuffer) { 398 kfree(data->wbuffer->buffer); 399 kfree(data->wbuffer); 400 } 401 kfree(data); 402 err = -ENOMEM; 403 __error: 404 module_put(entry->module); 405 __error1: 406 mutex_unlock(&info_mutex); 407 return err; 408 } 409 410 static int snd_info_entry_release(struct inode *inode, struct file *file) 411 { 412 struct snd_info_entry *entry; 413 struct snd_info_private_data *data; 414 int mode; 415 416 mode = file->f_flags & O_ACCMODE; 417 data = file->private_data; 418 entry = data->entry; 419 switch (entry->content) { 420 case SNDRV_INFO_CONTENT_TEXT: 421 if (data->rbuffer) { 422 kfree(data->rbuffer->buffer); 423 kfree(data->rbuffer); 424 } 425 if (data->wbuffer) { 426 if (entry->c.text.write) { 427 entry->c.text.write(entry, data->wbuffer); 428 if (data->wbuffer->error) { 429 snd_printk(KERN_WARNING "data write error to %s (%i)\n", 430 entry->name, 431 data->wbuffer->error); 432 } 433 } 434 kfree(data->wbuffer->buffer); 435 kfree(data->wbuffer); 436 } 437 break; 438 case SNDRV_INFO_CONTENT_DATA: 439 if (entry->c.ops->release) 440 entry->c.ops->release(entry, mode, 441 data->file_private_data); 442 break; 443 } 444 module_put(entry->module); 445 kfree(data); 446 return 0; 447 } 448 449 static unsigned int snd_info_entry_poll(struct file *file, poll_table * wait) 450 { 451 struct snd_info_private_data *data; 452 struct snd_info_entry *entry; 453 unsigned int mask; 454 455 data = file->private_data; 456 if (data == NULL) 457 return 0; 458 entry = data->entry; 459 mask = 0; 460 switch (entry->content) { 461 case SNDRV_INFO_CONTENT_DATA: 462 if (entry->c.ops->poll) 463 return entry->c.ops->poll(entry, 464 data->file_private_data, 465 file, wait); 466 if (entry->c.ops->read) 467 mask |= POLLIN | POLLRDNORM; 468 if (entry->c.ops->write) 469 mask |= POLLOUT | POLLWRNORM; 470 break; 471 } 472 return mask; 473 } 474 475 static long snd_info_entry_ioctl(struct file *file, unsigned int cmd, 476 unsigned long arg) 477 { 478 struct snd_info_private_data *data; 479 struct snd_info_entry *entry; 480 481 data = file->private_data; 482 if (data == NULL) 483 return 0; 484 entry = data->entry; 485 switch (entry->content) { 486 case SNDRV_INFO_CONTENT_DATA: 487 if (entry->c.ops->ioctl) 488 return entry->c.ops->ioctl(entry, 489 data->file_private_data, 490 file, cmd, arg); 491 break; 492 } 493 return -ENOTTY; 494 } 495 496 static int snd_info_entry_mmap(struct file *file, struct vm_area_struct *vma) 497 { 498 struct inode *inode = file->f_path.dentry->d_inode; 499 struct snd_info_private_data *data; 500 struct snd_info_entry *entry; 501 502 data = file->private_data; 503 if (data == NULL) 504 return 0; 505 entry = data->entry; 506 switch (entry->content) { 507 case SNDRV_INFO_CONTENT_DATA: 508 if (entry->c.ops->mmap) 509 return entry->c.ops->mmap(entry, 510 data->file_private_data, 511 inode, file, vma); 512 break; 513 } 514 return -ENXIO; 515 } 516 517 static const struct file_operations snd_info_entry_operations = 518 { 519 .owner = THIS_MODULE, 520 .llseek = snd_info_entry_llseek, 521 .read = snd_info_entry_read, 522 .write = snd_info_entry_write, 523 .poll = snd_info_entry_poll, 524 .unlocked_ioctl = snd_info_entry_ioctl, 525 .mmap = snd_info_entry_mmap, 526 .open = snd_info_entry_open, 527 .release = snd_info_entry_release, 528 }; 529 530 int __init snd_info_init(void) 531 { 532 struct proc_dir_entry *p; 533 534 p = proc_mkdir("asound", NULL); 535 if (p == NULL) 536 return -ENOMEM; 537 snd_proc_root = p; 538 #ifdef CONFIG_SND_OSSEMUL 539 { 540 struct snd_info_entry *entry; 541 if ((entry = snd_info_create_module_entry(THIS_MODULE, "oss", NULL)) == NULL) 542 return -ENOMEM; 543 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO; 544 if (snd_info_register(entry) < 0) { 545 snd_info_free_entry(entry); 546 return -ENOMEM; 547 } 548 snd_oss_root = entry; 549 } 550 #endif 551 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE) 552 { 553 struct snd_info_entry *entry; 554 if ((entry = snd_info_create_module_entry(THIS_MODULE, "seq", NULL)) == NULL) 555 return -ENOMEM; 556 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO; 557 if (snd_info_register(entry) < 0) { 558 snd_info_free_entry(entry); 559 return -ENOMEM; 560 } 561 snd_seq_root = entry; 562 } 563 #endif 564 snd_info_version_init(); 565 snd_minor_info_init(); 566 snd_minor_info_oss_init(); 567 snd_card_info_init(); 568 return 0; 569 } 570 571 int __exit snd_info_done(void) 572 { 573 snd_card_info_done(); 574 snd_minor_info_oss_done(); 575 snd_minor_info_done(); 576 snd_info_version_done(); 577 if (snd_proc_root) { 578 #if defined(CONFIG_SND_SEQUENCER) || defined(CONFIG_SND_SEQUENCER_MODULE) 579 snd_info_free_entry(snd_seq_root); 580 #endif 581 #ifdef CONFIG_SND_OSSEMUL 582 snd_info_free_entry(snd_oss_root); 583 #endif 584 snd_remove_proc_entry(NULL, snd_proc_root); 585 } 586 return 0; 587 } 588 589 /* 590 591 */ 592 593 594 /* 595 * create a card proc file 596 * called from init.c 597 */ 598 int snd_info_card_create(struct snd_card *card) 599 { 600 char str[8]; 601 struct snd_info_entry *entry; 602 603 if (snd_BUG_ON(!card)) 604 return -ENXIO; 605 606 sprintf(str, "card%i", card->number); 607 if ((entry = snd_info_create_module_entry(card->module, str, NULL)) == NULL) 608 return -ENOMEM; 609 entry->mode = S_IFDIR | S_IRUGO | S_IXUGO; 610 if (snd_info_register(entry) < 0) { 611 snd_info_free_entry(entry); 612 return -ENOMEM; 613 } 614 card->proc_root = entry; 615 return 0; 616 } 617 618 /* 619 * register the card proc file 620 * called from init.c 621 */ 622 int snd_info_card_register(struct snd_card *card) 623 { 624 struct proc_dir_entry *p; 625 626 if (snd_BUG_ON(!card)) 627 return -ENXIO; 628 629 if (!strcmp(card->id, card->proc_root->name)) 630 return 0; 631 632 p = proc_symlink(card->id, snd_proc_root, card->proc_root->name); 633 if (p == NULL) 634 return -ENOMEM; 635 card->proc_root_link = p; 636 return 0; 637 } 638 639 /* 640 * called on card->id change 641 */ 642 void snd_info_card_id_change(struct snd_card *card) 643 { 644 mutex_lock(&info_mutex); 645 if (card->proc_root_link) { 646 snd_remove_proc_entry(snd_proc_root, card->proc_root_link); 647 card->proc_root_link = NULL; 648 } 649 if (strcmp(card->id, card->proc_root->name)) 650 card->proc_root_link = proc_symlink(card->id, 651 snd_proc_root, 652 card->proc_root->name); 653 mutex_unlock(&info_mutex); 654 } 655 656 /* 657 * de-register the card proc file 658 * called from init.c 659 */ 660 void snd_info_card_disconnect(struct snd_card *card) 661 { 662 if (!card) 663 return; 664 mutex_lock(&info_mutex); 665 if (card->proc_root_link) { 666 snd_remove_proc_entry(snd_proc_root, card->proc_root_link); 667 card->proc_root_link = NULL; 668 } 669 if (card->proc_root) 670 snd_info_disconnect(card->proc_root); 671 mutex_unlock(&info_mutex); 672 } 673 674 /* 675 * release the card proc file resources 676 * called from init.c 677 */ 678 int snd_info_card_free(struct snd_card *card) 679 { 680 if (!card) 681 return 0; 682 snd_info_free_entry(card->proc_root); 683 card->proc_root = NULL; 684 return 0; 685 } 686 687 688 /** 689 * snd_info_get_line - read one line from the procfs buffer 690 * @buffer: the procfs buffer 691 * @line: the buffer to store 692 * @len: the max. buffer size - 1 693 * 694 * Reads one line from the buffer and stores the string. 695 * 696 * Returns zero if successful, or 1 if error or EOF. 697 */ 698 int snd_info_get_line(struct snd_info_buffer *buffer, char *line, int len) 699 { 700 int c = -1; 701 702 if (len <= 0 || buffer->stop || buffer->error) 703 return 1; 704 while (--len > 0) { 705 c = buffer->buffer[buffer->curr++]; 706 if (c == '\n') { 707 if (buffer->curr >= buffer->size) 708 buffer->stop = 1; 709 break; 710 } 711 *line++ = c; 712 if (buffer->curr >= buffer->size) { 713 buffer->stop = 1; 714 break; 715 } 716 } 717 while (c != '\n' && !buffer->stop) { 718 c = buffer->buffer[buffer->curr++]; 719 if (buffer->curr >= buffer->size) 720 buffer->stop = 1; 721 } 722 *line = '\0'; 723 return 0; 724 } 725 726 EXPORT_SYMBOL(snd_info_get_line); 727 728 /** 729 * snd_info_get_str - parse a string token 730 * @dest: the buffer to store the string token 731 * @src: the original string 732 * @len: the max. length of token - 1 733 * 734 * Parses the original string and copy a token to the given 735 * string buffer. 736 * 737 * Returns the updated pointer of the original string so that 738 * it can be used for the next call. 739 */ 740 const char *snd_info_get_str(char *dest, const char *src, int len) 741 { 742 int c; 743 744 while (*src == ' ' || *src == '\t') 745 src++; 746 if (*src == '"' || *src == '\'') { 747 c = *src++; 748 while (--len > 0 && *src && *src != c) { 749 *dest++ = *src++; 750 } 751 if (*src == c) 752 src++; 753 } else { 754 while (--len > 0 && *src && *src != ' ' && *src != '\t') { 755 *dest++ = *src++; 756 } 757 } 758 *dest = 0; 759 while (*src == ' ' || *src == '\t') 760 src++; 761 return src; 762 } 763 764 EXPORT_SYMBOL(snd_info_get_str); 765 766 /** 767 * snd_info_create_entry - create an info entry 768 * @name: the proc file name 769 * 770 * Creates an info entry with the given file name and initializes as 771 * the default state. 772 * 773 * Usually called from other functions such as 774 * snd_info_create_card_entry(). 775 * 776 * Returns the pointer of the new instance, or NULL on failure. 777 */ 778 static struct snd_info_entry *snd_info_create_entry(const char *name) 779 { 780 struct snd_info_entry *entry; 781 entry = kzalloc(sizeof(*entry), GFP_KERNEL); 782 if (entry == NULL) 783 return NULL; 784 entry->name = kstrdup(name, GFP_KERNEL); 785 if (entry->name == NULL) { 786 kfree(entry); 787 return NULL; 788 } 789 entry->mode = S_IFREG | S_IRUGO; 790 entry->content = SNDRV_INFO_CONTENT_TEXT; 791 mutex_init(&entry->access); 792 INIT_LIST_HEAD(&entry->children); 793 INIT_LIST_HEAD(&entry->list); 794 return entry; 795 } 796 797 /** 798 * snd_info_create_module_entry - create an info entry for the given module 799 * @module: the module pointer 800 * @name: the file name 801 * @parent: the parent directory 802 * 803 * Creates a new info entry and assigns it to the given module. 804 * 805 * Returns the pointer of the new instance, or NULL on failure. 806 */ 807 struct snd_info_entry *snd_info_create_module_entry(struct module * module, 808 const char *name, 809 struct snd_info_entry *parent) 810 { 811 struct snd_info_entry *entry = snd_info_create_entry(name); 812 if (entry) { 813 entry->module = module; 814 entry->parent = parent; 815 } 816 return entry; 817 } 818 819 EXPORT_SYMBOL(snd_info_create_module_entry); 820 821 /** 822 * snd_info_create_card_entry - create an info entry for the given card 823 * @card: the card instance 824 * @name: the file name 825 * @parent: the parent directory 826 * 827 * Creates a new info entry and assigns it to the given card. 828 * 829 * Returns the pointer of the new instance, or NULL on failure. 830 */ 831 struct snd_info_entry *snd_info_create_card_entry(struct snd_card *card, 832 const char *name, 833 struct snd_info_entry * parent) 834 { 835 struct snd_info_entry *entry = snd_info_create_entry(name); 836 if (entry) { 837 entry->module = card->module; 838 entry->card = card; 839 entry->parent = parent; 840 } 841 return entry; 842 } 843 844 EXPORT_SYMBOL(snd_info_create_card_entry); 845 846 static void snd_info_disconnect(struct snd_info_entry *entry) 847 { 848 struct list_head *p, *n; 849 struct proc_dir_entry *root; 850 851 list_for_each_safe(p, n, &entry->children) { 852 snd_info_disconnect(list_entry(p, struct snd_info_entry, list)); 853 } 854 855 if (! entry->p) 856 return; 857 list_del_init(&entry->list); 858 root = entry->parent == NULL ? snd_proc_root : entry->parent->p; 859 snd_BUG_ON(!root); 860 snd_remove_proc_entry(root, entry->p); 861 entry->p = NULL; 862 } 863 864 static int snd_info_dev_free_entry(struct snd_device *device) 865 { 866 struct snd_info_entry *entry = device->device_data; 867 snd_info_free_entry(entry); 868 return 0; 869 } 870 871 static int snd_info_dev_register_entry(struct snd_device *device) 872 { 873 struct snd_info_entry *entry = device->device_data; 874 return snd_info_register(entry); 875 } 876 877 /** 878 * snd_card_proc_new - create an info entry for the given card 879 * @card: the card instance 880 * @name: the file name 881 * @entryp: the pointer to store the new info entry 882 * 883 * Creates a new info entry and assigns it to the given card. 884 * Unlike snd_info_create_card_entry(), this function registers the 885 * info entry as an ALSA device component, so that it can be 886 * unregistered/released without explicit call. 887 * Also, you don't have to register this entry via snd_info_register(), 888 * since this will be registered by snd_card_register() automatically. 889 * 890 * The parent is assumed as card->proc_root. 891 * 892 * For releasing this entry, use snd_device_free() instead of 893 * snd_info_free_entry(). 894 * 895 * Returns zero if successful, or a negative error code on failure. 896 */ 897 int snd_card_proc_new(struct snd_card *card, const char *name, 898 struct snd_info_entry **entryp) 899 { 900 static struct snd_device_ops ops = { 901 .dev_free = snd_info_dev_free_entry, 902 .dev_register = snd_info_dev_register_entry, 903 /* disconnect is done via snd_info_card_disconnect() */ 904 }; 905 struct snd_info_entry *entry; 906 int err; 907 908 entry = snd_info_create_card_entry(card, name, card->proc_root); 909 if (! entry) 910 return -ENOMEM; 911 if ((err = snd_device_new(card, SNDRV_DEV_INFO, entry, &ops)) < 0) { 912 snd_info_free_entry(entry); 913 return err; 914 } 915 if (entryp) 916 *entryp = entry; 917 return 0; 918 } 919 920 EXPORT_SYMBOL(snd_card_proc_new); 921 922 /** 923 * snd_info_free_entry - release the info entry 924 * @entry: the info entry 925 * 926 * Releases the info entry. Don't call this after registered. 927 */ 928 void snd_info_free_entry(struct snd_info_entry * entry) 929 { 930 if (entry == NULL) 931 return; 932 if (entry->p) { 933 mutex_lock(&info_mutex); 934 snd_info_disconnect(entry); 935 mutex_unlock(&info_mutex); 936 } 937 kfree(entry->name); 938 if (entry->private_free) 939 entry->private_free(entry); 940 kfree(entry); 941 } 942 943 EXPORT_SYMBOL(snd_info_free_entry); 944 945 /** 946 * snd_info_register - register the info entry 947 * @entry: the info entry 948 * 949 * Registers the proc info entry. 950 * 951 * Returns zero if successful, or a negative error code on failure. 952 */ 953 int snd_info_register(struct snd_info_entry * entry) 954 { 955 struct proc_dir_entry *root, *p = NULL; 956 957 if (snd_BUG_ON(!entry)) 958 return -ENXIO; 959 root = entry->parent == NULL ? snd_proc_root : entry->parent->p; 960 mutex_lock(&info_mutex); 961 p = create_proc_entry(entry->name, entry->mode, root); 962 if (!p) { 963 mutex_unlock(&info_mutex); 964 return -ENOMEM; 965 } 966 if (!S_ISDIR(entry->mode)) 967 p->proc_fops = &snd_info_entry_operations; 968 p->size = entry->size; 969 p->data = entry; 970 entry->p = p; 971 if (entry->parent) 972 list_add_tail(&entry->list, &entry->parent->children); 973 mutex_unlock(&info_mutex); 974 return 0; 975 } 976 977 EXPORT_SYMBOL(snd_info_register); 978 979 /* 980 981 */ 982 983 static struct snd_info_entry *snd_info_version_entry; 984 985 static void snd_info_version_read(struct snd_info_entry *entry, struct snd_info_buffer *buffer) 986 { 987 snd_iprintf(buffer, 988 "Advanced Linux Sound Architecture Driver Version " 989 CONFIG_SND_VERSION CONFIG_SND_DATE ".\n" 990 ); 991 } 992 993 static int __init snd_info_version_init(void) 994 { 995 struct snd_info_entry *entry; 996 997 entry = snd_info_create_module_entry(THIS_MODULE, "version", NULL); 998 if (entry == NULL) 999 return -ENOMEM; 1000 entry->c.text.read = snd_info_version_read; 1001 if (snd_info_register(entry) < 0) { 1002 snd_info_free_entry(entry); 1003 return -ENOMEM; 1004 } 1005 snd_info_version_entry = entry; 1006 return 0; 1007 } 1008 1009 static int __exit snd_info_version_done(void) 1010 { 1011 snd_info_free_entry(snd_info_version_entry); 1012 return 0; 1013 } 1014 1015 #endif /* CONFIG_PROC_FS */ 1016