From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rick Bronson Subject: Re: WM8731 using I2S on omap3 McBSP2 issues Date: Thu, 24 Sep 2009 11:00:52 -0700 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from samwise.efn.org (efn.org [206.192.230.249]) by alsa0.perex.cz (Postfix) with ESMTP id 3197F243B8 for ; Thu, 24 Sep 2009 20:00:54 +0200 (CEST) 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 Mark, > This suggests that the DMA isn't happening which usually means that the > CPU isn't seeing all the clocks it's supposed to. I'm not familiar > enough with the OMAP internals to know if you've set the CPU up > properly. I've poured over the relavent code for this and am pretty sure I don't need to touch it. The same code works on the beagleboard, at least the DMA part. But you never know... > > I get no audio output, other than a "click" when the 8731 is > > initialized upon boot. When I look at the signals the McBSP2_DX line > > just goes low for the duration of the "aplay", it does not toggle. The > > other lines look fine. The file is at > > If you try a record then does the ADCDAT line show a signal? I tried this and the ADCDAT does show a signal. See http://www.efn.org/~rick/pub/win10586.jpg The bottom five traces are as follows: McBSP2_CLKX -> I2S_CLK -> I2S_BCLK -> BCLK */\ McBSP2_FSX -> I2S_FRM -> LRCLK -> DACLRC and ADCLRC*/\ McBSP2_DR <- I2S_RXD <- ACDDAT */\ McBSP_CLKS <- I2S_MCLK <- CLKOUT */\ McBSP2_DX -> I2S_TXD -> DACDAT */\ BTW, when I do a aplay, the trace looks the same except ACDDAT is low. I still get a write error though: beagle:~# arecord -t wav -f cd -d 1500 dar.wav Recording WAVE 'dar.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo arecord: pcm_read:1348: read error: Input/output error Rick