RE: [PATCH] ASoC: rt715: add main capture switch and main capture volume control

From: "Yang, Libin" <libin.yang@intel.com>
To: Jack Yu <jack.yu@realtek.com>, Jaroslav Kysela <perex@perex.cz>,
	Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
	"broonie@kernel.org" <broonie@kernel.org>,
	"lgirdwood@gmail.com" <lgirdwood@gmail.com>,
	Takashi Iwai <tiwai@suse.de>
Cc: "Oder Chiou" <oder_chiou@realtek.com>,
	"alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>,
	"lars@metafoo.de" <lars@metafoo.de>,
	"Derek [方德義]" <derek.fang@realtek.com>,
	"Liao, Bard" <bard.liao@intel.com>,
	"Shuming [范書銘]" <shumingf@realtek.com>,
	"Flove(HsinFu)" <flove@realtek.com>
Subject: RE: [PATCH] ASoC: rt715: add main capture switch and main capture volume control
Date: Wed, 6 Jan 2021 09:39:50 +0000	[thread overview]
Message-ID: <PH0PR11MB5046042ED34F28095C35A62990D00@PH0PR11MB5046.namprd11.prod.outlook.com> (raw)
In-Reply-To: <0dad47e2445e474ea0a982163521f986@realtek.com>

> >
> > >>>> 3) wait until UCM can describe this hardware and set the DAC
> > >>>> values manually to a sensible value via sequences (the specific
> > >>>> hardware levels can be set using the conditions in UCM)
> > >>>
> > >>> Not an option, there are products that need to ship soon.
> > >>
> > >> It's the easiest method for now. It's just about to change the UCM
> > >> files without any other changes in the kernel / user space. It's
> > >> heavily used for SST drivers, isn't?
> > >>
> > >> The current UCM upstream modifies only SOF volume levels (PGA
> > >> Master
> > Capture).
> > >
> > > that's not right, see above.
> > >
> > > I may have misunderstood your point for 3). I assumed you'd need a
> > > description coming from the kernel, as we did before for the
> > > components (cfg-mics, etc). How would UCM know which of the controls
> > > to use without any change to the kernel?
> >
> > Ideally, yes - it will help to reduce the configuration and the driver
> > already knows more about the hardware. But we can do DMI matching in
> > UCM for now, too.
> >
> 
> @Libin  Is this modification workable for you? I'd like to know your opinion
> about it. Thanks.

I think Jaroslav's suggestion of matching DMI is reasonable. 
Only special platforms should use this feature. Non-dell or 
some old dell platforms should not use this feature if I understand 
correctly based on 
https://www.spinics.net/lists/alsa-devel/msg118123.html
In the above link, Mario said the MIC LED is controlled by HW, not the SW.

So the codec driver won't control MIC LED. It means on other platforms 
which doesn't support the feature of HW controlling LED, using the new
kcontrol in UCM will cause some issues. When user press the MIC
mute key, the MIC LED won't change the status.

Regards,
Libin

> 
> > Example of the sysfs substitution:
> >
> >   ${sys:class/dmi/id/sys_vendor}
> >   ${sys:class/dmi/id/product_version}
> >
> > 						Jaroslav
> >
> > --
> > Jaroslav Kysela <perex@perex.cz>
> > Linux Sound Maintainer; ALSA Project; Red Hat, Inc.
> >
> > ------Please consider the environment before printing this e-mail.