From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Ujfalusi Subject: Re: Channel swapping issue on TI OMAP3/TWL4030 Date: Wed, 16 Feb 2011 09:20:21 +0200 Message-ID: <4D5B7AB5.201@nokia.com> References: <8CD98E75F0E83E2-63C-14642@web-mmc-m05.sysops.aol.com> <8CD9A87EF4FB765-1218-647@web-mmc-m03.sysops.aol.com> <4D5A2466.2060705@nokia.com> <8CD9B43DFD8A17C-DE8-B3DD@web-mmc-d01.sysops.aol.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mgw-sa02.nokia.com (smtp.nokia.com [147.243.1.48]) by alsa0.perex.cz (Postfix) with ESMTP id 1BE8B24414 for ; Wed, 16 Feb 2011 08:20:23 +0100 (CET) In-Reply-To: <8CD9B43DFD8A17C-DE8-B3DD@web-mmc-d01.sysops.aol.com> 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: "ext ylin@mail.com" Cc: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On 02/15/11 18:23, ext ylin@mail.com wrote: > = >> I forgot to ask: >> what mode you are using the McBSP? >> Is it in element, or threshold mode? >> You can check/change the McBSP mode in: >> /sys/devices/platform/omap-mcbsp.2/dma_op_mode > = > It is in threshold mode, with max threshold 1023. I will try other = > modes. This sounds safe, give the fact that the McBSP2 FIFO is 1280 word long. The McBSP FIFO configuration has been corrected in newer kernels. One thing that I would try is to synchronize the McBSP2 FIFO configuration with the period size you use: 48KHz/stereo/16bit 10ms =3D 480 samples, so configure the McBSP2 FIFO to 960 (for both tx, and rx threshold). Might not help, but it worth a try... >>> For playing, the left and right are the same data, we could not = > tell if >>> the channel switch happens to playback as well. >> >> I see. Is there a way for you to run your application to capture only, >> and from a separate app (aplay?) play a sample, which has audio only = > on >> one channel? > = > I can fill zero to one of the play channel in our app to test it. Great. Let's see, if the swap also happens in the playback path as well. -- = P=E9ter