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