On Sun, 07 Feb 2021 21:11:57 +0100, Jaroslav Kysela wrote: > > [DO NOT MERGE!] > [This is just an early proposal for comments] > [The code is not tested / debugged] > > The recent laptops have usually two LEDs assigned to reflect > the speaker and microphone mute state. This implementation > adds a tiny layer on top of the control API which calculates > the state for those LEDs using the driver callbacks. > > Two new access flags are introduced to describe the controls > which affects the audio path settings (an easy path for drivers). > > The LED resource can be shared with multiple sound cards with > this code. The user space controls may be added to the state > chain, too. > > This code should replace the LED code in the HDA driver and > add a possibility to easy extend the other drivers (ASoC > codecs etc.). Having a common helper in the ALSA core sounds like a good way to go. My slight concern is that this will end up having the dependency on LEDS stuff unconditionally when CONFIG_SND_LED=y. Also, are those new access flags exposed to user-space intentionally, so that user-space gets some information? Last but not least: I'm not sure whether we should limit to only two LEDs (mic and spk). I'm afraid that there will be more LEDs in future; people love decorations :) thanks, Takashi
