From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raymond Yau Subject: Re: Verifying mixer dB data/Invalid dB data from USB cards, especially Aureon 5.1 MkII Date: Wed, 24 Feb 2010 19:49:26 +0800 Message-ID: <4f3252891002240349p144fddc2oda20f856a30ba900@mail.gmail.com> References: <4f3252891002171748tdcaa87n4d11d9880c0043e3@mail.gmail.com> <20100218181322.GB5606@tango.0pointer.de> <4f3252891002190257u608073c3l48f2251d8a6458ee@mail.gmail.com> <20100219151328.GC25873@tango.0pointer.de> <4f3252891002202001gb6df8cg6c023c52e7d8394a@mail.gmail.com> <20100221192951.GD30380@tango.0pointer.de> <4B83A912.1050501@ladisch.de> <20100223223234.GB5313@tango.0pointer.de> <4B84EAC1.8040701@ladisch.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pw0-f51.google.com (mail-pw0-f51.google.com [209.85.160.51]) by alsa0.perex.cz (Postfix) with ESMTP id 7CE34103906 for ; Wed, 24 Feb 2010 12:49:28 +0100 (CET) Received: by pwi9 with SMTP id 9so4221602pwi.38 for ; Wed, 24 Feb 2010 03:49:27 -0800 (PST) In-Reply-To: <4B84EAC1.8040701@ladisch.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org 2010/2/24 Clemens Ladisch > Lennart Poettering wrote: > > On Tue, 23.02.10 11:08, Clemens Ladisch (clemens@ladisch.de) wrote: > > > Lennart Poettering wrote: > > > > Unfortunately there is no way from the simple mixer to the lower > level > > > > mixer. > > > > > > From the check_unplugged function in > alsa-utils/alsamixer/mixer_widget.c: > > > > > > err = snd_mixer_get_hctl(mixer, mixer_device_name, &hctl); > > > if (err >= 0) > > > ctl = snd_hctl_ctl(hctl); > > > > But that still doesn't give me a hint which snd_ctl_eleme_t belongs to > > which snd_mixer_eleme_t, does it? > > Not really; the point of the simple mixer interface is to abstract away > some of the ctl naming conventions. > > > > > It would be great if the smixer would include some API that gives me > a > > > > hint to which device/subdevice a specific snd_mixer_elem_t belongs > to. > > > > > > Often, there is no 1:1 correspondence between mixer elements and PCM > > > devices. Only mixer controls with interface PCM (not MIXER) have > (sub-) > > > device numbers, and at the moment this is used only for controls that > > > are associated with the streams of hardware-mixing-capable cards. > > > > Which are not that many, right? Not HDA at least? > > No, most recent hardware was designed for software mixing. Only the > snd-emu10k1, snd-via82xx and snd-ymfpci drivers implement such controls. > > > Regards, > Clemens > > The current implementation of HDA capturing subdevices are almost as same as those playback subdevices of hardware mixing sound card each subdevice support the same format , rate , channels , the number of input sources are also the same The only difference is the type IFACE_MIXER and IFACE_PCM since using IFACE_PCM will break most mixer application