diff options
Diffstat (limited to '')
| -rw-r--r-- | sound/core/control_led.c | 795 |
1 files changed, 795 insertions, 0 deletions
diff --git a/sound/core/control_led.c b/sound/core/control_led.c new file mode 100644 index 000000000000..f975cc85772b --- /dev/null +++ b/sound/core/control_led.c @@ -0,0 +1,795 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * LED state routines for driver control interface + * Copyright (c) 2021 by Jaroslav Kysela <perex@perex.cz> + */ + +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/leds.h> +#include <sound/core.h> +#include <sound/control.h> + +MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>"); +MODULE_DESCRIPTION("ALSA control interface to LED trigger code."); +MODULE_LICENSE("GPL"); + +#define MAX_LED (((SNDRV_CTL_ELEM_ACCESS_MIC_LED - SNDRV_CTL_ELEM_ACCESS_SPK_LED) \ + >> SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) + 1) + +#define to_led_card_dev(_dev) \ + container_of(_dev, struct snd_ctl_led_card, dev) + +enum snd_ctl_led_mode { + MODE_FOLLOW_MUTE = 0, + MODE_FOLLOW_ROUTE, + MODE_OFF, + MODE_ON, +}; + +struct snd_ctl_led_card { + struct device dev; + int number; + struct snd_ctl_led *led; +}; + +struct snd_ctl_led { + struct device dev; + struct list_head controls; + const char *name; + unsigned int group; + enum led_audio trigger_type; + enum snd_ctl_led_mode mode; + struct snd_ctl_led_card *cards[SNDRV_CARDS]; +}; + +struct snd_ctl_led_ctl { + struct list_head list; + struct snd_card *card; + unsigned int access; + struct snd_kcontrol *kctl; + unsigned int index_offset; +}; + +static DEFINE_MUTEX(snd_ctl_led_mutex); +static bool snd_ctl_led_card_valid[SNDRV_CARDS]; +static struct snd_ctl_led snd_ctl_leds[MAX_LED] = { + { + .name = "speaker", + .group = (SNDRV_CTL_ELEM_ACCESS_SPK_LED >> SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) - 1, + .trigger_type = LED_AUDIO_MUTE, + .mode = MODE_FOLLOW_MUTE, + }, + { + .name = "mic", + .group = (SNDRV_CTL_ELEM_ACCESS_MIC_LED >> SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) - 1, + .trigger_type = LED_AUDIO_MICMUTE, + .mode = MODE_FOLLOW_MUTE, + }, +}; + +static void snd_ctl_led_sysfs_add(struct snd_card *card); +static void snd_ctl_led_sysfs_remove(struct snd_card *card); + +#define UPDATE_ROUTE(route, cb) \ + do { \ + int route2 = (cb); \ + if (route2 >= 0) \ + route = route < 0 ? route2 : (route | route2); \ + } while (0) + +static inline unsigned int access_to_group(unsigned int access) +{ + return ((access & SNDRV_CTL_ELEM_ACCESS_LED_MASK) >> + SNDRV_CTL_ELEM_ACCESS_LED_SHIFT) - 1; +} + +static inline unsigned int group_to_access(unsigned int group) +{ + return (group + 1) << SNDRV_CTL_ELEM_ACCESS_LED_SHIFT; +} + +static struct snd_ctl_led *snd_ctl_led_get_by_access(unsigned int access) +{ + unsigned int group = access_to_group(access); + if (group >= MAX_LED) + return NULL; + return &snd_ctl_leds[group]; +} + +/* + * A note for callers: + * The two static variables info and value are protected using snd_ctl_led_mutex. + */ +static int snd_ctl_led_get(struct snd_ctl_led_ctl *lctl) +{ + static struct snd_ctl_elem_info info; + static struct snd_ctl_elem_value value; + struct snd_kcontrol *kctl = lctl->kctl; + unsigned int i; + int result; + + memset(&info, 0, sizeof(info)); + info.id = kctl->id; + info.id.index += lctl->index_offset; + info.id.numid += lctl->index_offset; + result = kctl->info(kctl, &info); + if (result < 0) + return -1; + memset(&value, 0, sizeof(value)); + value.id = info.id; + result = kctl->get(kctl, &value); + if (result < 0) + return -1; + if (info.type == SNDRV_CTL_ELEM_TYPE_BOOLEAN || + info.type == SNDRV_CTL_ELEM_TYPE_INTEGER) { + for (i = 0; i < info.count; i++) + if (value.value.integer.value[i] != info.value.integer.min) + return 1; + } else if (info.type == SNDRV_CTL_ELEM_TYPE_INTEGER64) { + for (i = 0; i < info.count; i++) + if (value.value.integer64.value[i] != info.value.integer64.min) + return 1; + } + return 0; +} + +static void snd_ctl_led_set_state(struct snd_card *card, unsigned int access, + struct snd_kcontrol *kctl, unsigned int ioff) +{ + struct snd_ctl_led *led; + struct snd_ctl_led_ctl *lctl; + int route; + bool found; + + led = snd_ctl_led_get_by_access(access); + if (!led) + return; + route = -1; + found = false; + mutex_lock(&snd_ctl_led_mutex); + /* the card may not be registered (active) at this point */ + if (card && !snd_ctl_led_card_valid[card->number]) { + mutex_unlock(&snd_ctl_led_mutex); + return; + } + list_for_each_entry(lctl, &led->controls, list) { + if (lctl->kctl == kctl && lctl->index_offset == ioff) + found = true; + UPDATE_ROUTE(route, snd_ctl_led_get(lctl)); + } + if (!found && kctl && card) { + lctl = kzalloc(sizeof(*lctl), GFP_KERNEL); + if (lctl) { + lctl->card = card; + lctl->access = access; + lctl->kctl = kctl; + lctl->index_offset = ioff; + list_add(&lctl->list, &led->controls); + UPDATE_ROUTE(route, snd_ctl_led_get(lctl)); + } + } + mutex_unlock(&snd_ctl_led_mutex); + switch (led->mode) { + case MODE_OFF: route = 1; break; + case MODE_ON: route = 0; break; + case MODE_FOLLOW_ROUTE: if (route >= 0) route ^= 1; break; + case MODE_FOLLOW_MUTE: /* noop */ break; + } + if (route >= 0) + ledtrig_audio_set(led->trigger_type, route ? LED_OFF : LED_ON); +} + +static struct snd_ctl_led_ctl *snd_ctl_led_find(struct snd_kcontrol *kctl, unsigned int ioff) +{ + struct list_head *controls; + struct snd_ctl_led_ctl *lctl; + unsigned int group; + + for (group = 0; group < MAX_LED; group++) { + controls = &snd_ctl_leds[group].controls; + list_for_each_entry(lctl, controls, list) + if (lctl->kctl == kctl && lctl->index_offset == ioff) + return lctl; + } + return NULL; +} + +static unsigned int snd_ctl_led_remove(struct snd_kcontrol *kctl, unsigned int ioff, + unsigned int access) +{ + struct snd_ctl_led_ctl *lctl; + unsigned int ret = 0; + + mutex_lock(&snd_ctl_led_mutex); + lctl = snd_ctl_led_find(kctl, ioff); + if (lctl && (access == 0 || access != lctl->access)) { + ret = lctl->access; + list_del(&lctl->list); + kfree(lctl); + } + mutex_unlock(&snd_ctl_led_mutex); + return ret; +} + +static void snd_ctl_led_notify(struct snd_card *card, unsigned int mask, + struct snd_kcontrol *kctl, unsigned int ioff) +{ + struct snd_kcontrol_volatile *vd; + unsigned int access, access2; + + if (mask == SNDRV_CTL_EVENT_MASK_REMOVE) { + access = snd_ctl_led_remove(kctl, ioff, 0); + if (access) + snd_ctl_led_set_state(card, access, NULL, 0); + } else if (mask & SNDRV_CTL_EVENT_MASK_INFO) { + vd = &kctl->vd[ioff]; + access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; + access2 = snd_ctl_led_remove(kctl, ioff, access); + if (access2) + snd_ctl_led_set_state(card, access2, NULL, 0); + if (access) + snd_ctl_led_set_state(card, access, kctl, ioff); + } else if ((mask & (SNDRV_CTL_EVENT_MASK_ADD | + SNDRV_CTL_EVENT_MASK_VALUE)) != 0) { + vd = &kctl->vd[ioff]; + access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; + if (access) + snd_ctl_led_set_state(card, access, kctl, ioff); + } +} + +static int snd_ctl_led_set_id(int card_number, struct snd_ctl_elem_id *id, + unsigned int group, bool set) +{ + struct snd_card *card; + struct snd_kcontrol *kctl; + struct snd_kcontrol_volatile *vd; + unsigned int ioff, access, new_access; + int err = 0; + + card = snd_card_ref(card_number); + if (card) { + down_write(&card->controls_rwsem); + kctl = snd_ctl_find_id(card, id); + if (kctl) { + ioff = snd_ctl_get_ioff(kctl, id); + vd = &kctl->vd[ioff]; + access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; + if (access != 0 && access != group_to_access(group)) { + err = -EXDEV; + goto unlock; + } + new_access = vd->access & ~SNDRV_CTL_ELEM_ACCESS_LED_MASK; + if (set) + new_access |= group_to_access(group); + if (new_access != vd->access) { + vd->access = new_access; + snd_ctl_led_notify(card, SNDRV_CTL_EVENT_MASK_INFO, kctl, ioff); + } + } else { + err = -ENOENT; + } +unlock: + up_write(&card->controls_rwsem); + snd_card_unref(card); + } else { + err = -ENXIO; + } + return err; +} + +static void snd_ctl_led_refresh(void) +{ + unsigned int group; + + for (group = 0; group < MAX_LED; group++) + snd_ctl_led_set_state(NULL, group_to_access(group), NULL, 0); +} + +static void snd_ctl_led_ctl_destroy(struct snd_ctl_led_ctl *lctl) +{ + list_del(&lctl->list); + kfree(lctl); +} + +static void snd_ctl_led_clean(struct snd_card *card) +{ + unsigned int group; + struct snd_ctl_led *led; + struct snd_ctl_led_ctl *lctl; + + for (group = 0; group < MAX_LED; group++) { + led = &snd_ctl_leds[group]; +repeat: + list_for_each_entry(lctl, &led->controls, list) + if (!card || lctl->card == card) { + snd_ctl_led_ctl_destroy(lctl); + goto repeat; + } + } +} + +static int snd_ctl_led_reset(int card_number, unsigned int group) +{ + struct snd_card *card; + struct snd_ctl_led *led; + struct snd_ctl_led_ctl *lctl; + struct snd_kcontrol_volatile *vd; + bool change = false; + + card = snd_card_ref(card_number); + if (!card) + return -ENXIO; + + mutex_lock(&snd_ctl_led_mutex); + if (!snd_ctl_led_card_valid[card_number]) { + mutex_unlock(&snd_ctl_led_mutex); + snd_card_unref(card); + return -ENXIO; + } + led = &snd_ctl_leds[group]; +repeat: + list_for_each_entry(lctl, &led->controls, list) + if (lctl->card == card) { + vd = &lctl->kctl->vd[lctl->index_offset]; + vd->access &= ~group_to_access(group); + snd_ctl_led_ctl_destroy(lctl); + change = true; + goto repeat; + } + mutex_unlock(&snd_ctl_led_mutex); + if (change) + snd_ctl_led_set_state(NULL, group_to_access(group), NULL, 0); + snd_card_unref(card); + return 0; +} + +static void snd_ctl_led_register(struct snd_card *card) +{ + struct snd_kcontrol *kctl; + unsigned int ioff; + + if (snd_BUG_ON(card->number < 0 || + card->number >= ARRAY_SIZE(snd_ctl_led_card_valid))) + return; + mutex_lock(&snd_ctl_led_mutex); + snd_ctl_led_card_valid[card->number] = true; + mutex_unlock(&snd_ctl_led_mutex); + /* the register callback is already called with held card->controls_rwsem */ + list_for_each_entry(kctl, &card->controls, list) + for (ioff = 0; ioff < kctl->count; ioff++) + snd_ctl_led_notify(card, SNDRV_CTL_EVENT_MASK_VALUE, kctl, ioff); + snd_ctl_led_refresh(); + snd_ctl_led_sysfs_add(card); +} + +static void snd_ctl_led_disconnect(struct snd_card *card) +{ + snd_ctl_led_sysfs_remove(card); + mutex_lock(&snd_ctl_led_mutex); + snd_ctl_led_card_valid[card->number] = false; + snd_ctl_led_clean(card); + mutex_unlock(&snd_ctl_led_mutex); + snd_ctl_led_refresh(); +} + +static void snd_ctl_led_card_release(struct device *dev) +{ + struct snd_ctl_led_card *led_card = to_led_card_dev(dev); + + kfree(led_card); +} + +static void snd_ctl_led_release(struct device *dev) +{ +} + +static void snd_ctl_led_dev_release(struct device *dev) +{ +} + +/* + * sysfs + */ + +static ssize_t mode_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct snd_ctl_led *led = container_of(dev, struct snd_ctl_led, dev); + const char *str = NULL; + + switch (led->mode) { + case MODE_FOLLOW_MUTE: str = "follow-mute"; break; + case MODE_FOLLOW_ROUTE: str = "follow-route"; break; + case MODE_ON: str = "on"; break; + case MODE_OFF: str = "off"; break; + } + return sysfs_emit(buf, "%s\n", str); +} + +static ssize_t mode_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct snd_ctl_led *led = container_of(dev, struct snd_ctl_led, dev); + char _buf[16]; + size_t l = min(count, sizeof(_buf) - 1); + enum snd_ctl_led_mode mode; + + memcpy(_buf, buf, l); + _buf[l] = '\0'; + if (strstr(_buf, "mute")) + mode = MODE_FOLLOW_MUTE; + else if (strstr(_buf, "route")) + mode = MODE_FOLLOW_ROUTE; + else if (strncmp(_buf, "off", 3) == 0 || strncmp(_buf, "0", 1) == 0) + mode = MODE_OFF; + else if (strncmp(_buf, "on", 2) == 0 || strncmp(_buf, "1", 1) == 0) + mode = MODE_ON; + else + return count; + + mutex_lock(&snd_ctl_led_mutex); + led->mode = mode; + mutex_unlock(&snd_ctl_led_mutex); + + snd_ctl_led_set_state(NULL, group_to_access(led->group), NULL, 0); + return count; +} + +static ssize_t brightness_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct snd_ctl_led *led = container_of(dev, struct snd_ctl_led, dev); + + return sysfs_emit(buf, "%u\n", ledtrig_audio_get(led->trigger_type)); +} + +static DEVICE_ATTR_RW(mode); +static DEVICE_ATTR_RO(brightness); + +static struct attribute *snd_ctl_led_dev_attrs[] = { + &dev_attr_mode.attr, + &dev_attr_brightness.attr, + NULL, +}; + +static const struct attribute_group snd_ctl_led_dev_attr_group = { + .attrs = snd_ctl_led_dev_attrs, +}; + +static const struct attribute_group *snd_ctl_led_dev_attr_groups[] = { + &snd_ctl_led_dev_attr_group, + NULL, +}; + +static char *find_eos(char *s) +{ + while (*s && *s != ',') + s++; + if (*s) + s++; + return s; +} + +static char *parse_uint(char *s, unsigned int *val) +{ + unsigned long long res; + if (kstrtoull(s, 10, &res)) + res = 0; + *val = res; + return find_eos(s); +} + +static char *parse_string(char *s, char *val, size_t val_size) +{ + if (*s == '"' || *s == '\'') { + char c = *s; + s++; + while (*s && *s != c) { + if (val_size > 1) { + *val++ = *s; + val_size--; + } + s++; + } + } else { + while (*s && *s != ',') { + if (val_size > 1) { + *val++ = *s; + val_size--; + } + s++; + } + } + *val = '\0'; + if (*s) + s++; + return s; +} + +static char *parse_iface(char *s, snd_ctl_elem_iface_t *val) +{ + if (!strncasecmp(s, "card", 4)) + *val = SNDRV_CTL_ELEM_IFACE_CARD; + else if (!strncasecmp(s, "mixer", 5)) + *val = SNDRV_CTL_ELEM_IFACE_MIXER; + return find_eos(s); +} + +/* + * These types of input strings are accepted: + * + * unsigned integer - numid (equivaled to numid=UINT) + * string - basic mixer name (equivalent to iface=MIXER,name=STR) + * numid=UINT + * [iface=MIXER,][device=UINT,][subdevice=UINT,]name=STR[,index=UINT] + */ +static ssize_t set_led_id(struct snd_ctl_led_card *led_card, const char *buf, size_t count, + bool attach) +{ + char buf2[256], *s, *os; + size_t len = max(sizeof(s) - 1, count); + struct snd_ctl_elem_id id; + int err; + + strncpy(buf2, buf, len); + buf2[len] = '\0'; + memset(&id, 0, sizeof(id)); + id.iface = SNDRV_CTL_ELEM_IFACE_MIXER; + s = buf2; + while (*s) { + os = s; + if (!strncasecmp(s, "numid=", 6)) { + s = parse_uint(s + 6, &id.numid); + } else if (!strncasecmp(s, "iface=", 6)) { + s = parse_iface(s + 6, &id.iface); + } else if (!strncasecmp(s, "device=", 7)) { + s = parse_uint(s + 7, &id.device); + } else if (!strncasecmp(s, "subdevice=", 10)) { + s = parse_uint(s + 10, &id.subdevice); + } else if (!strncasecmp(s, "name=", 5)) { + s = parse_string(s + 5, id.name, sizeof(id.name)); + } else if (!strncasecmp(s, "index=", 6)) { + s = parse_uint(s + 6, &id.index); + } else if (s == buf2) { + while (*s) { + if (*s < '0' || *s > '9') + break; + s++; + } + if (*s == '\0') + parse_uint(buf2, &id.numid); + else { + for (; *s >= ' '; s++); + *s = '\0'; + strscpy(id.name, buf2, sizeof(id.name)); + } + break; + } + if (*s == ',') + s++; + if (s == os) + break; + } + + err = snd_ctl_led_set_id(led_card->number, &id, led_card->led->group, attach); + if (err < 0) + return err; + + return count; +} + +static ssize_t attach_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); + return set_led_id(led_card, buf, count, true); +} + +static ssize_t detach_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); + return set_led_id(led_card, buf, count, false); +} + +static ssize_t reset_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); + int err; + + if (count > 0 && buf[0] == '1') { + err = snd_ctl_led_reset(led_card->number, led_card->led->group); + if (err < 0) + return err; + } + return count; +} + +static ssize_t list_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); + struct snd_card *card; + struct snd_ctl_led_ctl *lctl; + size_t l = 0; + + card = snd_card_ref(led_card->number); + if (!card) + return -ENXIO; + down_read(&card->controls_rwsem); + mutex_lock(&snd_ctl_led_mutex); + if (snd_ctl_led_card_valid[led_card->number]) { + list_for_each_entry(lctl, &led_card->led->controls, list) { + if (lctl->card != card) + continue; + if (l) + l += sysfs_emit_at(buf, l, " "); + l += sysfs_emit_at(buf, l, "%u", + lctl->kctl->id.numid + lctl->index_offset); + } + } + mutex_unlock(&snd_ctl_led_mutex); + up_read(&card->controls_rwsem); + snd_card_unref(card); + return l; +} + +static DEVICE_ATTR_WO(attach); +static DEVICE_ATTR_WO(detach); +static DEVICE_ATTR_WO(reset); +static DEVICE_ATTR_RO(list); + +static struct attribute *snd_ctl_led_card_attrs[] = { + &dev_attr_attach.attr, + &dev_attr_detach.attr, + &dev_attr_reset.attr, + &dev_attr_list.attr, + NULL, +}; + +static const struct attribute_group snd_ctl_led_card_attr_group = { + .attrs = snd_ctl_led_card_attrs, +}; + +static const struct attribute_group *snd_ctl_led_card_attr_groups[] = { + &snd_ctl_led_card_attr_group, + NULL, +}; + +static struct device snd_ctl_led_dev; + +static void snd_ctl_led_sysfs_add(struct snd_card *card) +{ + unsigned int group; + struct snd_ctl_led_card *led_card; + struct snd_ctl_led *led; + char link_name[32]; + + for (group = 0; group < MAX_LED; group++) { + led = &snd_ctl_leds[group]; + led_card = kzalloc(sizeof(*led_card), GFP_KERNEL); + if (!led_card) + goto cerr2; + led_card->number = card->number; + led_card->led = led; + device_initialize(&led_card->dev); + led_card->dev.release = snd_ctl_led_card_release; + if (dev_set_name(&led_card->dev, "card%d", card->number) < 0) + goto cerr; + led_card->dev.parent = &led->dev; + led_card->dev.groups = snd_ctl_led_card_attr_groups; + if (device_add(&led_card->dev)) + goto cerr; + led->cards[card->number] = led_card; + snprintf(link_name, sizeof(link_name), "led-%s", led->name); + WARN(sysfs_create_link(&card->ctl_dev.kobj, &led_card->dev.kobj, link_name), + "can't create symlink to controlC%i device\n", card->number); + WARN(sysfs_create_link(&led_card->dev.kobj, &card->card_dev.kobj, "card"), + "can't create symlink to card%i\n", card->number); + + continue; +cerr: + put_device(&led_card->dev); +cerr2: + printk(KERN_ERR "snd_ctl_led: unable to add card%d", card->number); + } +} + +static void snd_ctl_led_sysfs_remove(struct snd_card *card) +{ + unsigned int group; + struct snd_ctl_led_card *led_card; + struct snd_ctl_led *led; + char link_name[32]; + + for (group = 0; group < MAX_LED; group++) { + led = &snd_ctl_leds[group]; + led_card = led->cards[card->number]; + if (!led_card) + continue; + snprintf(link_name, sizeof(link_name), "led-%s", led->name); + sysfs_remove_link(&card->ctl_dev.kobj, link_name); + sysfs_remove_link(&led_card->dev.kobj, "card"); + device_unregister(&led_card->dev); + led->cards[card->number] = NULL; + } +} + +/* + * Control layer registration + */ +static struct snd_ctl_layer_ops snd_ctl_led_lops = { + .module_name = SND_CTL_LAYER_MODULE_LED, + .lregister = snd_ctl_led_register, + .ldisconnect = snd_ctl_led_disconnect, + .lnotify = snd_ctl_led_notify, +}; + +static int __init snd_ctl_led_init(void) +{ + struct snd_ctl_led *led; + unsigned int group; + + device_initialize(&snd_ctl_led_dev); + snd_ctl_led_dev.class = sound_class; + snd_ctl_led_dev.release = snd_ctl_led_dev_release; + dev_set_name(&snd_ctl_led_dev, "ctl-led"); + if (device_add(&snd_ctl_led_dev)) { + put_device(&snd_ctl_led_dev); + return -ENOMEM; + } + for (group = 0; group < MAX_LED; group++) { + led = &snd_ctl_leds[group]; + INIT_LIST_HEAD(&led->controls); + device_initialize(&led->dev); + led->dev.parent = &snd_ctl_led_dev; + led->dev.release = snd_ctl_led_release; + led->dev.groups = snd_ctl_led_dev_attr_groups; + dev_set_name(&led->dev, led->name); + if (device_add(&led->dev)) { + put_device(&led->dev); + for (; group > 0; group--) { + led = &snd_ctl_leds[group - 1]; + device_unregister(&led->dev); + } + device_unregister(&snd_ctl_led_dev); + return -ENOMEM; + } + } + snd_ctl_register_layer(&snd_ctl_led_lops); + return 0; +} + +static void __exit snd_ctl_led_exit(void) +{ + struct snd_ctl_led *led; + struct snd_card *card; + unsigned int group, card_number; + + snd_ctl_disconnect_layer(&snd_ctl_led_lops); + for (card_number = 0; card_number < SNDRV_CARDS; card_number++) { + if (!snd_ctl_led_card_valid[card_number]) + continue; + card = snd_card_ref(card_number); + if (card) { + snd_ctl_led_sysfs_remove(card); + snd_card_unref(card); + } + } + for (group = 0; group < MAX_LED; group++) { + led = &snd_ctl_leds[group]; + device_unregister(&led->dev); + } + device_unregister(&snd_ctl_led_dev); + snd_ctl_led_clean(NULL); +} + +module_init(snd_ctl_led_init) +module_exit(snd_ctl_led_exit) |