From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Ujfalusi Subject: Re: Channel swapping issue on TI OMAP3/TWL4030 Date: Tue, 15 Feb 2011 08:59:50 +0200 Message-ID: <4D5A2466.2060705@nokia.com> References: <8CD98E75F0E83E2-63C-14642@web-mmc-m05.sysops.aol.com> <8CD9A87EF4FB765-1218-647@web-mmc-m03.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-da02.nokia.com (smtp.nokia.com [147.243.128.26]) by alsa0.perex.cz (Postfix) with ESMTP id AD202103844 for ; Tue, 15 Feb 2011 07:59:56 +0100 (CET) In-Reply-To: <8CD9A87EF4FB765-1218-647@web-mmc-m03.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 02/14/11 19:58, ext ylin@mail.com wrote: > = >> I have not experienced with channel swapping during capture.. >> It would help, if I know: >> what is your kernel version >> Source of the recording (digimic, HS, main mic, etc) > = > We are using 2.6.32. The source of the recording is using Analog Mic. = > The Left Main mic is always on, and Right Sub mic can be either on or = > off when this occurs. We are not using AUX or digimic. > = >> To clarify: >> you experience sudden channel switch during active recording, when >> the recording was running for few hours? >> Or is it that you start/stop the recording, and sometimes the channels >> are swapped? > = > It is sudden channel switch during active recording. There is no XRUN = > or any noticeable error when this happens. > = > This is a VoIP app, we have duplex audio when this happens. Both = > capture and playback are setup to run at 48kHz, 2 channel, S16_LE, with = > period size 10 mSec. 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 > 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? -- = P=E9ter