linux/drivers/leds/trigger/ledtrig-audio.c
Takashi Iwai faa2541f5b 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: 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>
2018-11-28 12:28:30 +01:00

45 lines
1.1 KiB
C

// 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");