Commit faa2541f authored by Takashi Iwai's avatar Takashi Iwai
Browse files

leds: trigger: Introduce audio mute LED trigger 



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: default avatarJacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: default avatarPavel Machek <pavel@ucw.cz>
Acked-by: default avatarPali Rohár <pali.rohar@gmail.com>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 9ff01193

drivers/leds/trigger/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -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

drivers/leds/trigger/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -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

drivers/leds/trigger/ledtrig-audio.c

0 → 100644
+44 −0
Original line number Diff line number Diff line 
// 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");

include/linux/leds.h

+20 −0
Original line number Diff line number Diff line
@@ -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 */

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