[alsa-devel] [RFC PATCH 3/4] ASoC: hdac_hdmi: refine hdmi jacks

[Takashi Iwai]

On Tue, 25 Jun 2019 08:02:45 +0200,
Yang, Libin wrote:
> 
> >
> >Sorry for a long delay for the hdmi jacks. I was busy on another critical issue
> >last 2 weeks. I have worked out the UCM configuration files. Please check the
> >attachment. It is a long file, so I use the attachment instead of the patch mode.
> >Based on my test, it works well. Could you please help review if the
> >configuration file is OK or not. I will do more test on the meantime, including
> >DPMST and NON-DPMST.
> 
> With some more tests on the new hdmi jack with UCM configuration, I found
> that the kernel patch can always notify the jack hotplug event to userspace
> correctly. However, the userspace can't set the amixer correctly based on
> the UCM configurations sometimes.
> 
> Here is the details:
> There are 3 PCMs on Intel platforms. Let's call them pcm1, pcm2, pcm3.
> And there are 3 pins (pin5, pin6, pin7). For DPMST, and each pin has 3 ports:
> port0, port1, port2.
> 
> For non-DPMST, we can set pin5 <=> pcm1, pin6 <=> pcm2, pin7 <=> pcm3.
> This can always work.
> 
> For DPMST, as there are 9 ports using 3 pcms. So we should assign
> 1 pcm to 3 ports. For example, pin5-port0, pin6-port1 and pin7-port2
> are using pcm1;  pin5-port1, pin6-port2 and pin7-port0 are using
> pcm2; pin5-port2; pin6-port3 and pin7-port1 are using pcm3.
> In this setting, we should setting the ConflictingDevice in UCM.
> For example, pin5-port0 is conflicting with pin6-port1 and pin7-port2.
> Hui and I found if we set one device conflicting with 2 devices, the
> amixer setting will be wrong and it will not following UCM configuration
> setting when we are hotplugging the monitors.

How wrong would it behave?  Only one of them is done?

> Hui and I thought this may be the alsa-lib or pulseaudio issue.

You can try alsaucm directly without PA, too.
But in general the conflicting device management is done in PA, so I'd
begin with tracking the PA UCM code at first.


thanks,

Takashi