From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Nikula Subject: Re: Please help in adding ams-delta support to ASoC Date: Tue, 2 Jun 2009 20:32:14 +0300 Message-ID: <20090602203214.9edb786d.jhnikula@gmail.com> References: <4A1BEBE3.8010306@tis.icnet.pl> <20090527095949.51ed4b83.jhnikula@gmail.com> <200905272058.55404.jkrzyszt@tis.icnet.pl> <4A23CC97.1020209@tis.icnet.pl> <20090601210413.7678bf42.jhnikula@gmail.com> <20090602092252.10a57fda.jhnikula@gmail.com> <4A252A8E.9060602@tis.icnet.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from fg-out-1718.google.com ([72.14.220.152]:51929 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754632AbZFBRcB (ORCPT ); Tue, 2 Jun 2009 13:32:01 -0400 In-Reply-To: <4A252A8E.9060602@tis.icnet.pl> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Janusz Krzysztofik Cc: linux-omap@vger.kernel.org, alsa-devel@vger.kernel.org On Tue, 02 Jun 2009 15:35:10 +0200 Janusz Krzysztofik wrote: > I am not sure if this is of any importance, but with the old working > code, playing /dev/urandom to /dev/dsp I get only 3-4 DMA interrupts > per second, while doing the same on a x86_64 via82cxxx results in > 40-50 device interrupts per second. > Looks like via specific since both OMAP3 Beagle and my desktop are generating about 4 audio interrupts per second. > I did not find any documentation on the codec itself, only on its > "master" modem chip cx81801. Regarding modem<->codec interface, there > were only pins with breif description specified for both chips, > nothing more, as this interface was probably not intended for access > from outside. From the codec side, it looks like this: > > - Sleep (SLEEP); input > - Master Clock (M_CLKIN); input > - Serial Clock (M_SCK); output > - Control (M_CNTRLSIN); input > - Serial Frame Sync (M_STROBE); output > - Serial Transmit Data (M_TXSIN); input > - Serial Receive Data (M_RXOUT); output > - Reset (POR); input > > However, I can't tell which lines are switched from modem to mcbsp > and which are kept connected to the modem chip all the time. > Anyway, it looks like we can be sure that both bit clock and frame > sync should come from codec to mcbsp. It is not clear for me if MCLK > is really used by the codec, or it is possible that it gets its > master clock from an other, modem related source, and if this does > really matter. > Hmm. Are there any possibility that ams_delta_latch2_write requires working MCLK for latch change? I noticed that older implementation was activating MCLK before latch and your ASoC patch does opposite. Sounds a bit far but worth to try. Probably you could use also older implementation to find out is the MCLK required for codec by commenting out vc_mclk control. > > At least one difference is that omap-mcbsp.c is constructing McBSP > > register bits itself while older implementation was passing raw > > register configuration from the board files. Probably you could try > > to hack omap_mcbsp_dai_hw_params and pass the same register > > settings there to see are there some missing bit in omap-mcbsp.c. > > OK, I'll see if I know how to do this. > Just hack the same "static struct omap_mcbsp_reg_cfg mcbsp_regs = { ..." in omap-mcbsp.c and pass that structure instead of &mcbsp_data->regs to omap_mcbsp_config in omap_mcbsp_dai_hw_params. -- Jarkko