On Tue, 23 Feb 2021 17:14:32 +0100, Jaroslav Kysela wrote: > > Dne 23. 02. 21 v 15:21 Takashi Iwai napsal(a): > > On Tue, 23 Feb 2021 15:09:30 +0100, > > Mark Brown wrote: > >> > >> On Tue, Feb 23, 2021 at 02:59:17PM +0100, Hans de Goede wrote: > >>> On 2/23/21 2:45 PM, Mark Brown wrote: > >>>> On Mon, Feb 15, 2021 at 03:24:19PM +0100, Hans de Goede wrote: > >> > >>>> Why just these particular controls - what if a system has separate mutes > >>>> for speakers or something? > >> > >>> These are the main volume controls, which are always in the output / input > >>> path independent on if we are outputting to e.g. speakers or the headphones. > >> > >>> We want to use the main volume control for this, because there always is > >>> only 1 output mute LED and 1 input mute LED. Well at least that is the assumption > >>> the current ledtrig-audio.c code has. > >> > >>> The idea is to only turn the single LED on if we are sure there will be not > >>> sound output on any of the outputs, which is why we tie the LED to the > >>> mute switch on the main volume control. > >> > >> Right, so that might work well on your particular system with your > >> particular configuration but will it work well on other systems with > >> different hardware? It's not clear to me that it makes sense to go > >> through all the drivers picking controls that might be used for this > >> purpose - it seems both time consuming and error prone. Consider a > >> mostly digital device which has an ADC/DAC per input/output rather than > >> a central ADC/DAC with analogue muxing for example, or a system with > >> multiple DACs available for mixing together or analogue bypassess. > > > > That's one of my concerns in the recent actions for putting the > > hard-coded mute LED controls. So far, the only usage of led-audio > > trigger is HD-audio, and it's enabled only for selected devices and > > setups. OTOH, if we apply the audio-led trigger generically in ASoC > > codec driver, it's always done and might misfit; e.g. what happens if > > two codecs are present on the system?. > > That's the abstraction issue. We can use PCI, ACPI, DMI or DT checks at the > _right_ place (machine top-level code) to mark those controls with the LED > flags in the kernel space. I've never said that the right place is the generic > ASoC codec driver. > > On the other hand, rt5670 is really multi-purpose codec like HDA codecs with > the recommended usage/routing from the designer, so it might make sense to add > the default LED marking as we do for HDA. So do you mean that the LED feature should be selectively enabled like the current HD-audio? > > Of course, this implementation would make the integration much easier, > > and that's a big benefit. So I have a mixed feeling and not decided > > yet whether we should go for it right now... > > I think that we can reconsider the LED handling implementation later, when > someone brings something better on the table. What worried me is the plan to expose this capability to user-space. If it's only a kernel-internal, we can fix it in the kernel and nothing else broken, but if it's a part of API, that's not easy. So, if any, I'd like to avoid exposing to the user-space at first. (But then it comes to the question how to deal with a case like AMD ACP...) thanks, Takashi
