From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vinod Koul Subject: Re: [PATCH v4 6/8] ASoC: compress: Add support for DAI multicodec Date: Thu, 3 Jul 2014 21:45:17 +0530 Message-ID: <20140703161517.GQ2296@intel.com> References: <20140701164134.GH2296@intel.com> <53B400DE.3040205@baylibre.com> <20140703064147.GK2296@intel.com> <53B539E8.1000301@baylibre.com> <53B53C6B.8020707@metafoo.de> <53B540EE.30009@baylibre.com> <53B541F0.1040105@metafoo.de> <53B5428F.9050100@baylibre.com> <20140703120613.GP2296@intel.com> <20140703121846.GB410@sirena.org.uk> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============7841053771660829654==" Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by alsa0.perex.cz (Postfix) with ESMTP id 2EAF12658F4 for ; Thu, 3 Jul 2014 18:16:38 +0200 (CEST) In-Reply-To: <20140703121846.GB410@sirena.org.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: Mark Brown Cc: alsa-devel@alsa-project.org, misael.lopez@ti.com, Lars-Peter Clausen , lgirdwood@gmail.com, Benoit Cousson List-Id: alsa-devel@alsa-project.org --===============7841053771660829654== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="XvKFcGCOAo53UbWW" Content-Disposition: inline --XvKFcGCOAo53UbWW Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jul 03, 2014 at 01:18:46PM +0100, Mark Brown wrote: > > BUT Now thinking over this again, does this make sense do do with multi= ple > > codecs?? >=20 > > For folks haveing decoders in DSP inside SoC, the compressed device wil= l be > > actually a FE. The BE will be PCM to which codec would be linked. The f= olks > > supporting decoders inside codec like WM wont ever need this. >=20 > > Mark, do you agree to this? >=20 > > So re-thinking again on why we need this?? >=20 > The use case tends to be for applications that have one device per > physical output. This isn't normally mobile, it's normally high > performance audio applications where people are doing things to try to > electrically isolate the analogue outputs or dealing with high power so > need to keep speaker outputs physically separate. I can imagine set top > box type applications (which do use offloaded media decode) doing this. Not sure if I follow you, I have no idea of how these systems work. But if sound card has compressed device it would need to represent using DP= CM as we don't know the decoder PCM output. The multiple codecs would then connec= t to the PCM BE.=20 So on Compressed FE, we wont have multiple codecs. For codecs, the compressed audio will go to one codec, multiple ones wont m= ake sense. So how can we have a situation where we have compressed device linked to multiple codecs? --=20 ~Vinod --XvKFcGCOAo53UbWW Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQIcBAEBAgAGBQJTtYGVAAoJEHwUBw8lI4NHwh0P/37pJCCpGpxt82/d7vSu9CRn Zrcq6LEH21GPGHS29USpB5G4yZ5KYDhij5lva26Bzu09Zz+1BTeYJLgWho5Iyhbt YdAdp3WyWdyqQzj1MFLcybEvmsrGc/qy8O19DAiJoCC6OG8MrmMdQ120pSEvK88F CYNyQoDfcrV/UiBI3r5B5q8fO43ePaC7vcjN/mGq/dWvAjTrQyZjEVrGNZhkiKlI qM8/3ZOd1CW2hGpbuPJDA9uXoTKs1DI1a+yJUcOCOjXNm9gZsE/+CMLg7HKCv/1i UVe5oN2X8w8hh9eex8x3ww5IFTGR8CcZHpY557IuO2L+vm1lSKUQf7YNkR7Lzzf3 14bLoeRAYv7ThcCUfB+qxY42q26p1Z9BKplOeWupl6wKt3WAXT+sUp4Uc3qeX6IW NftTc+13MnwLJOqDSPKGl0yehbKQ3GCz+tZAGwN5D15f9Ff3NrR8oRSh/UdRVjYQ HARqfovrtvq39Pd/IclyHHygmXL1pBpZMBIgPhXQZZegm2M5lnI6qPE06ynGqM1I rvj2KHs0zrDm3UMXZ8aqLtXROnyhhKeJ8B5Z8arj6XLFrh7BMyhL5esUgHOeCCSv +KhvhVOyilf2DMVxZ7SD4MQ/PDI5eahvmb6grZEhdpcNaFQpVLJbTx/ZqXUSPzqw PYLttfYGZ916wHDSZfou =P34D -----END PGP SIGNATURE----- --XvKFcGCOAo53UbWW-- --===============7841053771660829654== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline --===============7841053771660829654==--