1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * LED state routines for driver control interface 4 * Copyright (c) 2021 by Jaroslav Kysela <perex@perex.cz> 5 */ 6 7 #include <linux/slab.h> 8 #include <linux/module.h> 9 #include <linux/leds.h> 10 #include <sound/core.h> 11 #include <sound/control.h> 12 13 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>"); 14 MODULE_DESCRIPTION("ALSA control interface to LED trigger code."); 15 MODULE_LICENSE("GPL"); 16 17 #define MAX_LED (((SNDRV_CTL_ELEM_ACCESS_MIC_LED - SNDRV_CTL_ELEM_ACCESS_SPK_LED) \ 18 >> SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) + 1) 19 20 #define to_led_card_dev(_dev) \ 21 container_of(_dev, struct snd_ctl_led_card, dev) 22 23 enum snd_ctl_led_mode { 24 MODE_FOLLOW_MUTE = 0, 25 MODE_FOLLOW_ROUTE, 26 MODE_OFF, 27 MODE_ON, 28 }; 29 30 struct snd_ctl_led_card { 31 struct device dev; 32 int number; 33 struct snd_ctl_led *led; 34 }; 35 36 struct snd_ctl_led { 37 struct device dev; 38 struct list_head controls; 39 const char *name; 40 unsigned int group; 41 enum led_audio trigger_type; 42 enum snd_ctl_led_mode mode; 43 struct snd_ctl_led_card *cards[SNDRV_CARDS]; 44 }; 45 46 struct snd_ctl_led_ctl { 47 struct list_head list; 48 struct snd_card *card; 49 unsigned int access; 50 struct snd_kcontrol *kctl; 51 unsigned int index_offset; 52 }; 53 54 static DEFINE_MUTEX(snd_ctl_led_mutex); 55 static bool snd_ctl_led_card_valid[SNDRV_CARDS]; 56 static struct snd_ctl_led snd_ctl_leds[MAX_LED] = { 57 { 58 .name = "speaker", 59 .group = (SNDRV_CTL_ELEM_ACCESS_SPK_LED >> SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) - 1, 60 .trigger_type = LED_AUDIO_MUTE, 61 .mode = MODE_FOLLOW_MUTE, 62 }, 63 { 64 .name = "mic", 65 .group = (SNDRV_CTL_ELEM_ACCESS_MIC_LED >> SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) - 1, 66 .trigger_type = LED_AUDIO_MICMUTE, 67 .mode = MODE_FOLLOW_MUTE, 68 }, 69 }; 70 71 static void snd_ctl_led_sysfs_add(struct snd_card *card); 72 static void snd_ctl_led_sysfs_remove(struct snd_card *card); 73 74 #define UPDATE_ROUTE(route, cb) \ 75 do { \ 76 int route2 = (cb); \ 77 if (route2 >= 0) \ 78 route = route < 0 ? route2 : (route | route2); \ 79 } while (0) 80 81 static inline unsigned int access_to_group(unsigned int access) 82 { 83 return ((access & SNDRV_CTL_ELEM_ACCESS_LED_MASK) >> 84 SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) - 1; 85 } 86 87 static inline unsigned int group_to_access(unsigned int group) 88 { 89 return (group + 1) << SNDRV_CTL_ELEM_ACCESS_LED_SHIFT; 90 } 91 92 static struct snd_ctl_led *snd_ctl_led_get_by_access(unsigned int access) 93 { 94 unsigned int group = access_to_group(access); 95 if (group >= MAX_LED) 96 return NULL; 97 return &snd_ctl_leds[group]; 98 } 99 100 /* 101 * A note for callers: 102 * The two static variables info and value are protected using snd_ctl_led_mutex. 103 */ 104 static int snd_ctl_led_get(struct snd_ctl_led_ctl *lctl) 105 { 106 static struct snd_ctl_elem_info info; 107 static struct snd_ctl_elem_value value; 108 struct snd_kcontrol *kctl = lctl->kctl; 109 unsigned int i; 110 int result; 111 112 memset(&info, 0, sizeof(info)); 113 info.id = kctl->id; 114 info.id.index += lctl->index_offset; 115 info.id.numid += lctl->index_offset; 116 result = kctl->info(kctl, &info); 117 if (result < 0) 118 return -1; 119 memset(&value, 0, sizeof(value)); 120 value.id = info.id; 121 result = kctl->get(kctl, &value); 122 if (result < 0) 123 return -1; 124 if (info.type == SNDRV_CTL_ELEM_TYPE_BOOLEAN || 125 info.type == SNDRV_CTL_ELEM_TYPE_INTEGER) { 126 for (i = 0; i < info.count; i++) 127 if (value.value.integer.value[i] != info.value.integer.min) 128 return 1; 129 } else if (info.type == SNDRV_CTL_ELEM_TYPE_INTEGER64) { 130 for (i = 0; i < info.count; i++) 131 if (value.value.integer64.value[i] != info.value.integer64.min) 132 return 1; 133 } 134 return 0; 135 } 136 137 static void snd_ctl_led_set_state(struct snd_card *card, unsigned int access, 138 struct snd_kcontrol *kctl, unsigned int ioff) 139 { 140 struct snd_ctl_led *led; 141 struct snd_ctl_led_ctl *lctl; 142 int route; 143 bool found; 144 145 led = snd_ctl_led_get_by_access(access); 146 if (!led) 147 return; 148 route = -1; 149 found = false; 150 mutex_lock(&snd_ctl_led_mutex); 151 /* the card may not be registered (active) at this point */ 152 if (card && !snd_ctl_led_card_valid[card->number]) { 153 mutex_unlock(&snd_ctl_led_mutex); 154 return; 155 } 156 list_for_each_entry(lctl, &led->controls, list) { 157 if (lctl->kctl == kctl && lctl->index_offset == ioff) 158 found = true; 159 UPDATE_ROUTE(route, snd_ctl_led_get(lctl)); 160 } 161 if (!found && kctl && card) { 162 lctl = kzalloc(sizeof(*lctl), GFP_KERNEL); 163 if (lctl) { 164 lctl->card = card; 165 lctl->access = access; 166 lctl->kctl = kctl; 167 lctl->index_offset = ioff; 168 list_add(&lctl->list, &led->controls); 169 UPDATE_ROUTE(route, snd_ctl_led_get(lctl)); 170 } 171 } 172 mutex_unlock(&snd_ctl_led_mutex); 173 switch (led->mode) { 174 case MODE_OFF: route = 1; break; 175 case MODE_ON: route = 0; break; 176 case MODE_FOLLOW_ROUTE: if (route >= 0) route ^= 1; break; 177 case MODE_FOLLOW_MUTE: /* noop */ break; 178 } 179 if (route >= 0) 180 ledtrig_audio_set(led->trigger_type, route ? LED_OFF : LED_ON); 181 } 182 183 static struct snd_ctl_led_ctl *snd_ctl_led_find(struct snd_kcontrol *kctl, unsigned int ioff) 184 { 185 struct list_head *controls; 186 struct snd_ctl_led_ctl *lctl; 187 unsigned int group; 188 189 for (group = 0; group < MAX_LED; group++) { 190 controls = &snd_ctl_leds[group].controls; 191 list_for_each_entry(lctl, controls, list) 192 if (lctl->kctl == kctl && lctl->index_offset == ioff) 193 return lctl; 194 } 195 return NULL; 196 } 197 198 static unsigned int snd_ctl_led_remove(struct snd_kcontrol *kctl, unsigned int ioff, 199 unsigned int access) 200 { 201 struct snd_ctl_led_ctl *lctl; 202 unsigned int ret = 0; 203 204 mutex_lock(&snd_ctl_led_mutex); 205 lctl = snd_ctl_led_find(kctl, ioff); 206 if (lctl && (access == 0 || access != lctl->access)) { 207 ret = lctl->access; 208 list_del(&lctl->list); 209 kfree(lctl); 210 } 211 mutex_unlock(&snd_ctl_led_mutex); 212 return ret; 213 } 214 215 static void snd_ctl_led_notify(struct snd_card *card, unsigned int mask, 216 struct snd_kcontrol *kctl, unsigned int ioff) 217 { 218 struct snd_kcontrol_volatile *vd; 219 unsigned int access, access2; 220 221 if (mask == SNDRV_CTL_EVENT_MASK_REMOVE) { 222 access = snd_ctl_led_remove(kctl, ioff, 0); 223 if (access) 224 snd_ctl_led_set_state(card, access, NULL, 0); 225 } else if (mask & SNDRV_CTL_EVENT_MASK_INFO) { 226 vd = &kctl->vd[ioff]; 227 access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; 228 access2 = snd_ctl_led_remove(kctl, ioff, access); 229 if (access2) 230 snd_ctl_led_set_state(card, access2, NULL, 0); 231 if (access) 232 snd_ctl_led_set_state(card, access, kctl, ioff); 233 } else if ((mask & (SNDRV_CTL_EVENT_MASK_ADD | 234 SNDRV_CTL_EVENT_MASK_VALUE)) != 0) { 235 vd = &kctl->vd[ioff]; 236 access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; 237 if (access) 238 snd_ctl_led_set_state(card, access, kctl, ioff); 239 } 240 } 241 242 static int snd_ctl_led_set_id(int card_number, struct snd_ctl_elem_id *id, 243 unsigned int group, bool set) 244 { 245 struct snd_card *card; 246 struct snd_kcontrol *kctl; 247 struct snd_kcontrol_volatile *vd; 248 unsigned int ioff, access, new_access; 249 int err = 0; 250 251 card = snd_card_ref(card_number); 252 if (card) { 253 down_write(&card->controls_rwsem); 254 kctl = snd_ctl_find_id(card, id); 255 if (kctl) { 256 ioff = snd_ctl_get_ioff(kctl, id); 257 vd = &kctl->vd[ioff]; 258 access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; 259 if (access != 0 && access != group_to_access(group)) { 260 err = -EXDEV; 261 goto unlock; 262 } 263 new_access = vd->access & ~SNDRV_CTL_ELEM_ACCESS_LED_MASK; 264 if (set) 265 new_access |= group_to_access(group); 266 if (new_access != vd->access) { 267 vd->access = new_access; 268 snd_ctl_led_notify(card, SNDRV_CTL_EVENT_MASK_INFO, kctl, ioff); 269 } 270 } else { 271 err = -ENOENT; 272 } 273 unlock: 274 up_write(&card->controls_rwsem); 275 snd_card_unref(card); 276 } else { 277 err = -ENXIO; 278 } 279 return err; 280 } 281 282 static void snd_ctl_led_refresh(void) 283 { 284 unsigned int group; 285 286 for (group = 0; group < MAX_LED; group++) 287 snd_ctl_led_set_state(NULL, group_to_access(group), NULL, 0); 288 } 289 290 static void snd_ctl_led_ctl_destroy(struct snd_ctl_led_ctl *lctl) 291 { 292 list_del(&lctl->list); 293 kfree(lctl); 294 } 295 296 static void snd_ctl_led_clean(struct snd_card *card) 297 { 298 unsigned int group; 299 struct snd_ctl_led *led; 300 struct snd_ctl_led_ctl *lctl; 301 302 for (group = 0; group < MAX_LED; group++) { 303 led = &snd_ctl_leds[group]; 304 repeat: 305 list_for_each_entry(lctl, &led->controls, list) 306 if (!card || lctl->card == card) { 307 snd_ctl_led_ctl_destroy(lctl); 308 goto repeat; 309 } 310 } 311 } 312 313 static int snd_ctl_led_reset(int card_number, unsigned int group) 314 { 315 struct snd_card *card; 316 struct snd_ctl_led *led; 317 struct snd_ctl_led_ctl *lctl; 318 struct snd_kcontrol_volatile *vd; 319 bool change = false; 320 321 card = snd_card_ref(card_number); 322 if (!card) 323 return -ENXIO; 324 325 mutex_lock(&snd_ctl_led_mutex); 326 if (!snd_ctl_led_card_valid[card_number]) { 327 mutex_unlock(&snd_ctl_led_mutex); 328 snd_card_unref(card); 329 return -ENXIO; 330 } 331 led = &snd_ctl_leds[group]; 332 repeat: 333 list_for_each_entry(lctl, &led->controls, list) 334 if (lctl->card == card) { 335 vd = &lctl->kctl->vd[lctl->index_offset]; 336 vd->access &= ~group_to_access(group); 337 snd_ctl_led_ctl_destroy(lctl); 338 change = true; 339 goto repeat; 340 } 341 mutex_unlock(&snd_ctl_led_mutex); 342 if (change) 343 snd_ctl_led_set_state(NULL, group_to_access(group), NULL, 0); 344 snd_card_unref(card); 345 return 0; 346 } 347 348 static void snd_ctl_led_register(struct snd_card *card) 349 { 350 struct snd_kcontrol *kctl; 351 unsigned int ioff; 352 353 if (snd_BUG_ON(card->number < 0 || 354 card->number >= ARRAY_SIZE(snd_ctl_led_card_valid))) 355 return; 356 mutex_lock(&snd_ctl_led_mutex); 357 snd_ctl_led_card_valid[card->number] = true; 358 mutex_unlock(&snd_ctl_led_mutex); 359 /* the register callback is already called with held card->controls_rwsem */ 360 list_for_each_entry(kctl, &card->controls, list) 361 for (ioff = 0; ioff < kctl->count; ioff++) 362 snd_ctl_led_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, kctl, ioff); 363 snd_ctl_led_refresh(); 364 snd_ctl_led_sysfs_add(card); 365 } 366 367 static void snd_ctl_led_disconnect(struct snd_card *card) 368 { 369 snd_ctl_led_sysfs_remove(card); 370 mutex_lock(&snd_ctl_led_mutex); 371 snd_ctl_led_card_valid[card->number] = false; 372 snd_ctl_led_clean(card); 373 mutex_unlock(&snd_ctl_led_mutex); 374 snd_ctl_led_refresh(); 375 } 376 377 static void snd_ctl_led_card_release(struct device *dev) 378 { 379 struct snd_ctl_led_card *led_card = to_led_card_dev(dev); 380 381 kfree(led_card); 382 } 383 384 static void snd_ctl_led_release(struct device *dev) 385 { 386 } 387 388 static void snd_ctl_led_dev_release(struct device *dev) 389 { 390 } 391 392 /* 393 * sysfs 394 */ 395 396 static ssize_t mode_show(struct device *dev, 397 struct device_attribute *attr, char *buf) 398 { 399 struct snd_ctl_led *led = container_of(dev, struct snd_ctl_led, dev); 400 const char *str = NULL; 401 402 switch (led->mode) { 403 case MODE_FOLLOW_MUTE: str = "follow-mute"; break; 404 case MODE_FOLLOW_ROUTE: str = "follow-route"; break; 405 case MODE_ON: str = "on"; break; 406 case MODE_OFF: str = "off"; break; 407 } 408 return sysfs_emit(buf, "%s\n", str); 409 } 410 411 static ssize_t mode_store(struct device *dev, 412 struct device_attribute *attr, 413 const char *buf, size_t count) 414 { 415 struct snd_ctl_led *led = container_of(dev, struct snd_ctl_led, dev); 416 char _buf[16]; 417 size_t l = min(count, sizeof(_buf) - 1); 418 enum snd_ctl_led_mode mode; 419 420 memcpy(_buf, buf, l); 421 _buf[l] = '\0'; 422 if (strstr(_buf, "mute")) 423 mode = MODE_FOLLOW_MUTE; 424 else if (strstr(_buf, "route")) 425 mode = MODE_FOLLOW_ROUTE; 426 else if (strncmp(_buf, "off", 3) == 0 || strncmp(_buf, "0", 1) == 0) 427 mode = MODE_OFF; 428 else if (strncmp(_buf, "on", 2) == 0 || strncmp(_buf, "1", 1) == 0) 429 mode = MODE_ON; 430 else 431 return count; 432 433 mutex_lock(&snd_ctl_led_mutex); 434 led->mode = mode; 435 mutex_unlock(&snd_ctl_led_mutex); 436 437 snd_ctl_led_set_state(NULL, group_to_access(led->group), NULL, 0); 438 return count; 439 } 440 441 static ssize_t brightness_show(struct device *dev, 442 struct device_attribute *attr, char *buf) 443 { 444 struct snd_ctl_led *led = container_of(dev, struct snd_ctl_led, dev); 445 446 return sysfs_emit(buf, "%u\n", ledtrig_audio_get(led->trigger_type)); 447 } 448 449 static DEVICE_ATTR_RW(mode); 450 static DEVICE_ATTR_RO(brightness); 451 452 static struct attribute *snd_ctl_led_dev_attrs[] = { 453 &dev_attr_mode.attr, 454 &dev_attr_brightness.attr, 455 NULL, 456 }; 457 458 static const struct attribute_group snd_ctl_led_dev_attr_group = { 459 .attrs = snd_ctl_led_dev_attrs, 460 }; 461 462 static const struct attribute_group *snd_ctl_led_dev_attr_groups[] = { 463 &snd_ctl_led_dev_attr_group, 464 NULL, 465 }; 466 467 static char *find_eos(char *s) 468 { 469 while (*s && *s != ',') 470 s++; 471 if (*s) 472 s++; 473 return s; 474 } 475 476 static char *parse_uint(char *s, unsigned int *val) 477 { 478 unsigned long long res; 479 if (kstrtoull(s, 10, &res)) 480 res = 0; 481 *val = res; 482 return find_eos(s); 483 } 484 485 static char *parse_string(char *s, char *val, size_t val_size) 486 { 487 if (*s == '"' || *s == '\'') { 488 char c = *s; 489 s++; 490 while (*s && *s != c) { 491 if (val_size > 1) { 492 *val++ = *s; 493 val_size--; 494 } 495 s++; 496 } 497 } else { 498 while (*s && *s != ',') { 499 if (val_size > 1) { 500 *val++ = *s; 501 val_size--; 502 } 503 s++; 504 } 505 } 506 *val = '\0'; 507 if (*s) 508 s++; 509 return s; 510 } 511 512 static char *parse_iface(char *s, snd_ctl_elem_iface_t *val) 513 { 514 if (!strncasecmp(s, "card", 4)) 515 *val = SNDRV_CTL_ELEM_IFACE_CARD; 516 else if (!strncasecmp(s, "mixer", 5)) 517 *val = SNDRV_CTL_ELEM_IFACE_MIXER; 518 return find_eos(s); 519 } 520 521 /* 522 * These types of input strings are accepted: 523 * 524 * unsigned integer - numid (equivaled to numid=UINT) 525 * string - basic mixer name (equivalent to iface=MIXER,name=STR) 526 * numid=UINT 527 * [iface=MIXER,][device=UINT,][subdevice=UINT,]name=STR[,index=UINT] 528 */ 529 static ssize_t set_led_id(struct snd_ctl_led_card *led_card, const char *buf, size_t count, 530 bool attach) 531 { 532 char buf2[256], *s, *os; 533 struct snd_ctl_elem_id id; 534 int err; 535 536 if (strscpy(buf2, buf, sizeof(buf2)) < 0) 537 return -E2BIG; 538 memset(&id, 0, sizeof(id)); 539 id.iface = SNDRV_CTL_ELEM_IFACE_MIXER; 540 s = buf2; 541 while (*s) { 542 os = s; 543 if (!strncasecmp(s, "numid=", 6)) { 544 s = parse_uint(s + 6, &id.numid); 545 } else if (!strncasecmp(s, "iface=", 6)) { 546 s = parse_iface(s + 6, &id.iface); 547 } else if (!strncasecmp(s, "device=", 7)) { 548 s = parse_uint(s + 7, &id.device); 549 } else if (!strncasecmp(s, "subdevice=", 10)) { 550 s = parse_uint(s + 10, &id.subdevice); 551 } else if (!strncasecmp(s, "name=", 5)) { 552 s = parse_string(s + 5, id.name, sizeof(id.name)); 553 } else if (!strncasecmp(s, "index=", 6)) { 554 s = parse_uint(s + 6, &id.index); 555 } else if (s == buf2) { 556 while (*s) { 557 if (*s < '0' || *s > '9') 558 break; 559 s++; 560 } 561 if (*s == '\0') 562 parse_uint(buf2, &id.numid); 563 else { 564 for (; *s >= ' '; s++); 565 *s = '\0'; 566 strscpy(id.name, buf2, sizeof(id.name)); 567 } 568 break; 569 } 570 if (*s == ',') 571 s++; 572 if (s == os) 573 break; 574 } 575 576 err = snd_ctl_led_set_id(led_card->number, &id, led_card->led->group, attach); 577 if (err < 0) 578 return err; 579 580 return count; 581 } 582 583 static ssize_t attach_store(struct device *dev, 584 struct device_attribute *attr, 585 const char *buf, size_t count) 586 { 587 struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); 588 return set_led_id(led_card, buf, count, true); 589 } 590 591 static ssize_t detach_store(struct device *dev, 592 struct device_attribute *attr, 593 const char *buf, size_t count) 594 { 595 struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); 596 return set_led_id(led_card, buf, count, false); 597 } 598 599 static ssize_t reset_store(struct device *dev, 600 struct device_attribute *attr, 601 const char *buf, size_t count) 602 { 603 struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); 604 int err; 605 606 if (count > 0 && buf[0] == '1') { 607 err = snd_ctl_led_reset(led_card->number, led_card->led->group); 608 if (err < 0) 609 return err; 610 } 611 return count; 612 } 613 614 static ssize_t list_show(struct device *dev, 615 struct device_attribute *attr, char *buf) 616 { 617 struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); 618 struct snd_card *card; 619 struct snd_ctl_led_ctl *lctl; 620 size_t l = 0; 621 622 card = snd_card_ref(led_card->number); 623 if (!card) 624 return -ENXIO; 625 down_read(&card->controls_rwsem); 626 mutex_lock(&snd_ctl_led_mutex); 627 if (snd_ctl_led_card_valid[led_card->number]) { 628 list_for_each_entry(lctl, &led_card->led->controls, list) { 629 if (lctl->card != card) 630 continue; 631 if (l) 632 l += sysfs_emit_at(buf, l, " "); 633 l += sysfs_emit_at(buf, l, "%u", 634 lctl->kctl->id.numid + lctl->index_offset); 635 } 636 } 637 mutex_unlock(&snd_ctl_led_mutex); 638 up_read(&card->controls_rwsem); 639 snd_card_unref(card); 640 return l; 641 } 642 643 static DEVICE_ATTR_WO(attach); 644 static DEVICE_ATTR_WO(detach); 645 static DEVICE_ATTR_WO(reset); 646 static DEVICE_ATTR_RO(list); 647 648 static struct attribute *snd_ctl_led_card_attrs[] = { 649 &dev_attr_attach.attr, 650 &dev_attr_detach.attr, 651 &dev_attr_reset.attr, 652 &dev_attr_list.attr, 653 NULL, 654 }; 655 656 static const struct attribute_group snd_ctl_led_card_attr_group = { 657 .attrs = snd_ctl_led_card_attrs, 658 }; 659 660 static const struct attribute_group *snd_ctl_led_card_attr_groups[] = { 661 &snd_ctl_led_card_attr_group, 662 NULL, 663 }; 664 665 static struct device snd_ctl_led_dev; 666 667 static void snd_ctl_led_sysfs_add(struct snd_card *card) 668 { 669 unsigned int group; 670 struct snd_ctl_led_card *led_card; 671 struct snd_ctl_led *led; 672 char link_name[32]; 673 674 for (group = 0; group < MAX_LED; group++) { 675 led = &snd_ctl_leds[group]; 676 led_card = kzalloc(sizeof(*led_card), GFP_KERNEL); 677 if (!led_card) 678 goto cerr2; 679 led_card->number = card->number; 680 led_card->led = led; 681 device_initialize(&led_card->dev); 682 led_card->dev.release = snd_ctl_led_card_release; 683 if (dev_set_name(&led_card->dev, "card%d", card->number) < 0) 684 goto cerr; 685 led_card->dev.parent = &led->dev; 686 led_card->dev.groups = snd_ctl_led_card_attr_groups; 687 if (device_add(&led_card->dev)) 688 goto cerr; 689 led->cards[card->number] = led_card; 690 snprintf(link_name, sizeof(link_name), "led-%s", led->name); 691 WARN(sysfs_create_link(&card->ctl_dev.kobj, &led_card->dev.kobj, link_name), 692 "can't create symlink to controlC%i device\n", card->number); 693 WARN(sysfs_create_link(&led_card->dev.kobj, &card->card_dev.kobj, "card"), 694 "can't create symlink to card%i\n", card->number); 695 696 continue; 697 cerr: 698 put_device(&led_card->dev); 699 cerr2: 700 printk(KERN_ERR "snd_ctl_led: unable to add card%d", card->number); 701 } 702 } 703 704 static void snd_ctl_led_sysfs_remove(struct snd_card *card) 705 { 706 unsigned int group; 707 struct snd_ctl_led_card *led_card; 708 struct snd_ctl_led *led; 709 char link_name[32]; 710 711 for (group = 0; group < MAX_LED; group++) { 712 led = &snd_ctl_leds[group]; 713 led_card = led->cards[card->number]; 714 if (!led_card) 715 continue; 716 snprintf(link_name, sizeof(link_name), "led-%s", led->name); 717 sysfs_remove_link(&card->ctl_dev.kobj, link_name); 718 sysfs_remove_link(&led_card->dev.kobj, "card"); 719 device_unregister(&led_card->dev); 720 led->cards[card->number] = NULL; 721 } 722 } 723 724 /* 725 * Control layer registration 726 */ 727 static struct snd_ctl_layer_ops snd_ctl_led_lops = { 728 .module_name = SND_CTL_LAYER_MODULE_LED, 729 .lregister = snd_ctl_led_register, 730 .ldisconnect = snd_ctl_led_disconnect, 731 .lnotify = snd_ctl_led_notify, 732 }; 733 734 static int __init snd_ctl_led_init(void) 735 { 736 struct snd_ctl_led *led; 737 unsigned int group; 738 739 device_initialize(&snd_ctl_led_dev); 740 snd_ctl_led_dev.class = sound_class; 741 snd_ctl_led_dev.release = snd_ctl_led_dev_release; 742 dev_set_name(&snd_ctl_led_dev, "ctl-led"); 743 if (device_add(&snd_ctl_led_dev)) { 744 put_device(&snd_ctl_led_dev); 745 return -ENOMEM; 746 } 747 for (group = 0; group < MAX_LED; group++) { 748 led = &snd_ctl_leds[group]; 749 INIT_LIST_HEAD(&led->controls); 750 device_initialize(&led->dev); 751 led->dev.parent = &snd_ctl_led_dev; 752 led->dev.release = snd_ctl_led_release; 753 led->dev.groups = snd_ctl_led_dev_attr_groups; 754 dev_set_name(&led->dev, led->name); 755 if (device_add(&led->dev)) { 756 put_device(&led->dev); 757 for (; group > 0; group--) { 758 led = &snd_ctl_leds[group - 1]; 759 device_unregister(&led->dev); 760 } 761 device_unregister(&snd_ctl_led_dev); 762 return -ENOMEM; 763 } 764 } 765 snd_ctl_register_layer(&snd_ctl_led_lops); 766 return 0; 767 } 768 769 static void __exit snd_ctl_led_exit(void) 770 { 771 struct snd_ctl_led *led; 772 struct snd_card *card; 773 unsigned int group, card_number; 774 775 snd_ctl_disconnect_layer(&snd_ctl_led_lops); 776 for (card_number = 0; card_number < SNDRV_CARDS; card_number++) { 777 if (!snd_ctl_led_card_valid[card_number]) 778 continue; 779 card = snd_card_ref(card_number); 780 if (card) { 781 snd_ctl_led_sysfs_remove(card); 782 snd_card_unref(card); 783 } 784 } 785 for (group = 0; group < MAX_LED; group++) { 786 led = &snd_ctl_leds[group]; 787 device_unregister(&led->dev); 788 } 789 device_unregister(&snd_ctl_led_dev); 790 snd_ctl_led_clean(NULL); 791 } 792 793 module_init(snd_ctl_led_init) 794 module_exit(snd_ctl_led_exit) 795