[RFC][PATCH 0/2] design a way to change audio Jack state by software

[Kai Vehmanen]

Hi,

On Wed, 9 Dec 2020, Jaroslav Kysela wrote:

> Dne 09. 12. 20 v 13:43 Hui Wang napsal(a):
> > After we change sth in the userspace audio stack like alsa-ucm or
> > pulseaudio, we want to perform remote audio auto test to verify if the
> > change introduce the regression or not, some of the tests are about
> > the defaut_sink/default_source or active_port switching, this needs

thanks Hui for the RFC.

I do think this is a very tempting capability to add. I understand 
Jaroslav's concerns as well, but there is clearly a category of issues 
where user-space functionality is broken due to a mismatch of element 
names between UCM file and the driver. I.e. the actual jack detection 
(codec hw and its driver) is working, but due to wrong UCM file chosen, 
wrong driven is chosen, or errors in either UCM or driver, event does not 
get parsed right and user ends with no audio.

A pure user-space test harness would not catch these, and building full 
automation of external codec events, is a complex task and coverage of 
devices is likely limited. 

The 'edid_override' debugfs interface in i915 is a bit similar. It allows
inject EDID content irrespectively of the actual monitor connected.

> Also, the first patch can be omitted if you just create another
> snd_jack_report() function for the user API and put the common code to the
> static function in jack.c.

++votes on this

Br, Kai