Re: [PATCH] ALSA: hda: Skip creating captures in SOF context

[Jaroslav Kysela]

On 05. 01. 23 13:36, Kai-Heng Feng wrote:
> On Mon, Aug 15, 2022 at 3:55 PM Kai-Heng Feng
> <kai.heng.feng@xxxxxxxxxxxxx> wrote:
> > On Wed, Jul 20, 2022 at 9:31 PM Pierre-Louis Bossart
> > <pierre-louis.bossart@xxxxxxxxxxxxxxx> wrote:
> > > On 7/20/22 02:52, Jaroslav Kysela wrote:
> > > > Dne 20. 07. 22 v 3:45 Kai-Heng Feng napsal(a):
> > > > > On Tue, Jul 19, 2022 at 11:41 PM Jaroslav Kysela <perex@xxxxxxxx> wrote:
> > > > > > Dne 19. 07. 22 v 16:47 Kai-Heng Feng napsal(a):
> > > > > > > On HP laptops that use SOF driver for DMIC, the micmute LED doesn't
> > > > > > > light up when mic is muted after commit 9b014266ef8a ("ASoC: SOF:
> > > > > > > topology: use new sound control LED layer").
> > > > > > >
> > > > > > > The micmute LED itself is still working via sysfs, but it doesn't follow
> > > > > > > mute anymore. That's because unlike vendors like Dell and Lenovo, HP
> > > > > > > laptops use HDA codec to control mute LEDs instead of ACPI. So on HP
> > > > > > > laptops, both SOF and HDA create captures with
> > > > > > > SNDRV_CTL_ELEM_ACCESS_MIC_LED access, snd_ctl_led_set_state() considers
> > > > > > > there are two different kcontrols and one of them is not muted.
> > > > > >
> > > > > > It does not mean that it's a wrong behavior. When both controls are muted, the
> > > > > > LED should be turned on. It just requires that all inputs are off (and it may
> > > > > > be the default - probably we can set in UCM or so). If you turn the "Capture
> > > > > > Switch" off in amixer / alsamixer, do things work as expected ?
> > > > >
> > > > > Yes. When all captures are muted the micmute LED is on.
> > > > >
> > > > > > > So skip creating captures for HDA when it's called from SOF, the
> > > > > > > captures are already handled by SOF.
> > > > > >
> > > > > > The capture controls are for other inputs like external analog microphone. If
> > > > > > it is required to suppress the MIC LED for some hardware, just skip the
> > > > > > "spec->mic_mute_led = 1" assignment in hda_generic.c . Also, the check
> > > > > > "codec->core.type != HDA_DEV_ASOC" is not sufficient, because you don't know,
> > > > > > if the topology really sets the MIC LED flag.
> > > > >
> > > > > AFAIK the external analog microphone on DMIC laptop is driven by SOF driver too.
> > > > > If those capture controls are indeed needed for external analog mics,
> > > > > use UCM to mute them by default won't work either.
> > > >
> > > > Could you describe this ? I though that only DMIC is handled by SOF when HDA
> > > > codec is in the system. There is a separate analog codec for external analog
> > > > microphone or the HDA codec is somehow connected to SOF/DSP ? If so, how ?
> > >
> > > The HDA codec is connected in the same way in all cases, there's no
> > > hardware/electrical/routing difference.
> > >
> > > When used, the SOF driver will handle ALL links, be they DMIC or
> > > HDAudio. The difference for HDaudio is that instead of a single DMA
> > > transfer (DDR->FIFO), we have a first 'Host' DMA into the DSP SRAM, some
> > > processing and a second 'Link' DMA from DSP SRAM to the HDaudio FIFO
> > > (reversed flow for capture).
> >
> > So is this approach sufficient for this issue? Or should I explore
> > other possibilities?
>
> A gentle ping...

This Mic LED problem was resolved through UCM for the moment:

https://github.com/alsa-project/alsa-ucm-conf/commit/79a8ec44d3dcf097f4a4492c506cbcf338324175

More discussion:

https://bugzilla.redhat.com/show_bug.cgi?id=2134824

					Jaroslav

--
Jaroslav Kysela <perex@xxxxxxxx>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.