From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Henningsson Subject: Re: [PATCH v2 2/3] route: Select slave chmap based on ttable information Date: Fri, 28 Feb 2014 14:52:46 +0100 Message-ID: <531094AE.1010408@canonical.com> References: <1393574227-25732-1-git-send-email-david.henningsson@canonical.com> <1393574227-25732-3-git-send-email-david.henningsson@canonical.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from youngberry.canonical.com (youngberry.canonical.com [91.189.89.112]) by alsa0.perex.cz (Postfix) with ESMTP id 475D026595C for ; Fri, 28 Feb 2014 14:52:48 +0100 (CET) In-Reply-To: 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: Raymond Yau Cc: tiwai@suse.de, ALSA Development Mailing List List-Id: alsa-devel@alsa-project.org On 02/28/2014 02:49 PM, Raymond Yau wrote: > > > > 2014-02-28 15:57 GMT+08:00 David Henningsson > >: > > It means we need to initialize this order: > > 1) Read the ttable to figure out which channels are present > 2) Open slave pcm and find a matching chmap > 3) Determine size of ttable (this can now depend on the chmap) > 4) Read ttable coefficients > 5) At prepare time, select the matching chmap > > > Do this patch assume the slave.pcm of the route plugin must have a > channel map ? No. In that case, it will fall back to ALSA's standard channel map ( FL -> 0, FR -> 1, etc). > are there any side effect when some of sound cards using route but does > not have channel map ? If there is no channel map, things should remain unchanged. > > > > e.g. ice1712, > > playback.pcm { > type hooks > slave.pcm { > type route > ttable.0.8 1 > ttable.1.9 1 > slave.pcm { > type hw > card $CARD > } > slave.format S32_LE > slave.channels 10 > } > > > rme9652, .... > > slave.pcm { > type route > slave { > pcm { > type hw > card $CARD > } > channels 26 > } > ttable.0.24 1 > ttable.1.25 1 > > -- David Henningsson, Canonical Ltd. https://launchpad.net/~diwic