From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: pcm512x driver: Mixer control naming issue Date: Mon, 16 Mar 2015 11:11:12 +0100 Message-ID: References: <5500DE5B.2020401@hmbedded.co.uk> <5502DAE1.30609@hmbedded.co.uk> <20150313182729.GE28806@sirena.org.uk> <55060771.7060200@hmbedded.co.uk> <5506A69B.1010601@hmbedded.co.uk> Mime-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mx2.suse.de (cantor2.suse.de [195.135.220.15]) by alsa0.perex.cz (Postfix) with ESMTP id 8DF952605D3 for ; Mon, 16 Mar 2015 11:11:13 +0100 (CET) In-Reply-To: <5506A69B.1010601@hmbedded.co.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Howard Mitchell Cc: alsa-devel@alsa-project.org, Mark Brown , Gordon Garrity List-Id: alsa-devel@alsa-project.org At Mon, 16 Mar 2015 09:47:07 +0000, Howard Mitchell wrote: > > On 16/03/15 07:47, Takashi Iwai wrote: > > At Sun, 15 Mar 2015 22:28:01 +0000, > > Howard Mitchell wrote: > >> On 13/03/15 18:27, Mark Brown wrote: > >>> On Fri, Mar 13, 2015 at 12:41:05PM +0000, Howard Mitchell wrote: > >>> > >>>> Boost Volume) provides a boost of +0.8dB. The hardware reset value of both > >>>> of these gain controls is 0dB, however, in the Raspbian distribution > >>>> 'Playback Volume' is being defaulted to -6dB. > >>>> * Either change the names of these controls to something that's not > >>>> affected by the alsa restore mechanism, > >>> You say "these controls" but it seems like only "Playback Volume" has > >>> a problem? My first suggestion would be to define "Analog" or > >>> "Analogue" as a prefix in ControlNames and then use that, that would > >>> avoid confusing applications while still fittig in with the naming > >>> convention. > >> Yes you are correct that it's only "Playback Volume" that is causing a > >> problem. However, I included "Playback Boost Volume" as it also provides > >> a selection of analogue gain so I think it should be treated similarly > >> for consistency. > > Did you read Documentation/sound/alsa/ControlNames.txt? > > It shows why "Playback Volume" is taken in that way while "Playback > > Boost Volume" not. Namely, the latter implies a volume control named > > "Playback Boost" which is applied generically -- i.e. the direction is > > unknown or applied to both playback and capture. > Sorry, what I meant by "treated similarly for consistency" is that > whatever solution is decided upon to fix the issue with "Playback > Volume" should also be applied to "Playback Boost Volume". > > Your comment about the direction being unknown for "Playback Boost > Volume" is interesting though as when running alsamixer I find that > "Playback Volume" is also listed as a capture control. Neither makes > sense of course as this device does not have a capture path. Congrats, you hit a bug in alsa-lib simple mixer layer. Feel free to submit a fix patch :) Takashi