[alsa-devel] [patch][saa7134] do not change mute state for capturing audio

Mauro Carvalho Chehab mchehab at infradead.org
Wed Jul 20 12:48:59 CEST 2011

Em 20-07-2011 07:45, Stas Sergeev escreveu:
> 20.07.2011 14:32, Mauro Carvalho Chehab wrote:
>> I won't keep discussing something that won't be merged, as it will
>> cause regressions.
> Please explain what regressions it will make!
> I am asking that question over and over again, and
> every time you either ignore it, or refer to an apps
> that use v4l2 ioctls, which are unaffected.
> I wonder why you don't want to explain what regressions
> do you have in mind...
>> If the application is starting streaming, audio should be expected on
>> devices
>> where the audio output is internally wired with the capture input.
>> This seems to be the case of your device. There's nothing that can be
>> done to fix a bad hardware design or the lack of enough information
>> from the device manufacturer.
> Well, until you explain the exact breakage of my proposal,
> I won't trust this. :)

I've said already: mplayer for example relies on such behavior to work. Reverting
it breaks mplayer. This is enough for me to NACK your patch.

>> I suspect, however, that not changing the GPIO's is a very bad idea, and
>> it will actually break audio for devices with external GPIO-based input
>> switches, but, as this version was already done, it might be useful for some
>> tests. A version 3 will follow shortly.
> I'll test at a week-end whatever we'll have to that date.

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