This patch adds a new LED trigger for coupling the audio mixer change with the LED on laptops or other devices. Currently there are two trigger types, "audio-mute" and "audio-micmute".
The audio driver triggers the LED brightness change via ledtrig_audio_set() call with the proper type (either mute or mic-mute). OTOH, the consumers may call ledtrig_audio_get() for the initial brightness value that may have been set by the audio driver beforehand.
This new stuff will be used by HD-audio codec driver and some platform drivers (thinkpad_acpi and dell-laptop, also upcoming huawei-wmi).
Acked-by: Jacek Anaszewski jacek.anaszewski@gmail.com Acked-by: Pavel Machek pavel@ucw.cz Acked-by: Pali Rohár pali.rohar@gmail.com Signed-off-by: Takashi Iwai tiwai@suse.de --- drivers/leds/trigger/Kconfig | 7 +++++ drivers/leds/trigger/Makefile | 1 + drivers/leds/trigger/ledtrig-audio.c | 44 ++++++++++++++++++++++++++++ include/linux/leds.h | 20 +++++++++++++ 4 files changed, 72 insertions(+) create mode 100644 drivers/leds/trigger/ledtrig-audio.c
diff --git a/drivers/leds/trigger/Kconfig b/drivers/leds/trigger/Kconfig index b76fc3cdc8f8..23cc85e2e0e5 100644 --- a/drivers/leds/trigger/Kconfig +++ b/drivers/leds/trigger/Kconfig @@ -136,4 +136,11 @@ config LEDS_TRIGGER_PATTERN which is a series of tuples, of brightness and duration (ms). If unsure, say N
+config LEDS_TRIGGER_AUDIO + tristate "Audio Mute LED Trigger" + help + This allows LEDs to be controlled by audio drivers for following + the audio mute and mic-mute changes. + If unsure, say N + endif # LEDS_TRIGGERS diff --git a/drivers/leds/trigger/Makefile b/drivers/leds/trigger/Makefile index 9bcb64ee8123..733a83e2a718 100644 --- a/drivers/leds/trigger/Makefile +++ b/drivers/leds/trigger/Makefile @@ -14,3 +14,4 @@ obj-$(CONFIG_LEDS_TRIGGER_CAMERA) += ledtrig-camera.o obj-$(CONFIG_LEDS_TRIGGER_PANIC) += ledtrig-panic.o obj-$(CONFIG_LEDS_TRIGGER_NETDEV) += ledtrig-netdev.o obj-$(CONFIG_LEDS_TRIGGER_PATTERN) += ledtrig-pattern.o +obj-$(CONFIG_LEDS_TRIGGER_AUDIO) += ledtrig-audio.o diff --git a/drivers/leds/trigger/ledtrig-audio.c b/drivers/leds/trigger/ledtrig-audio.c new file mode 100644 index 000000000000..f76621e88482 --- /dev/null +++ b/drivers/leds/trigger/ledtrig-audio.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Audio Mute LED trigger +// + +#include <linux/kernel.h> +#include <linux/leds.h> +#include <linux/module.h> + +static struct led_trigger *ledtrig_audio[NUM_AUDIO_LEDS]; +static enum led_brightness audio_state[NUM_AUDIO_LEDS]; + +enum led_brightness ledtrig_audio_get(enum led_audio type) +{ + return audio_state[type]; +} +EXPORT_SYMBOL_GPL(ledtrig_audio_get); + +void ledtrig_audio_set(enum led_audio type, enum led_brightness state) +{ + audio_state[type] = state; + led_trigger_event(ledtrig_audio[type], state); +} +EXPORT_SYMBOL_GPL(ledtrig_audio_set); + +static int __init ledtrig_audio_init(void) +{ + led_trigger_register_simple("audio-mute", + &ledtrig_audio[LED_AUDIO_MUTE]); + led_trigger_register_simple("audio-micmute", + &ledtrig_audio[LED_AUDIO_MICMUTE]); + return 0; +} +module_init(ledtrig_audio_init); + +static void __exit ledtrig_audio_exit(void) +{ + led_trigger_unregister_simple(ledtrig_audio[LED_AUDIO_MUTE]); + led_trigger_unregister_simple(ledtrig_audio[LED_AUDIO_MICMUTE]); +} +module_exit(ledtrig_audio_exit); + +MODULE_DESCRIPTION("LED trigger for audio mute control"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/leds.h b/include/linux/leds.h index 7393a316d9fa..580cbaef789a 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -487,4 +487,24 @@ struct led_pattern { int brightness; };
+enum led_audio { + LED_AUDIO_MUTE, /* master mute LED */ + LED_AUDIO_MICMUTE, /* mic mute LED */ + NUM_AUDIO_LEDS +}; + +#if IS_ENABLED(CONFIG_LEDS_TRIGGER_AUDIO) +enum led_brightness ledtrig_audio_get(enum led_audio type); +void ledtrig_audio_set(enum led_audio type, enum led_brightness state); +#else +static inline enum led_brightness ledtrig_audio_get(enum led_audio type) +{ + return LED_OFF; +} +static inline void ledtrig_audio_set(enum led_audio type, + enum led_brightness state) +{ +} +#endif + #endif /* __LINUX_LEDS_H_INCLUDED */