From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bo Shen Subject: Re: [PATCH 01/19] ASoC: atmel: Don't set unused struct snd_pcm_hardware fields Date: Mon, 6 Jan 2014 11:01:15 +0800 Message-ID: <52CA1C7B.3000900@atmel.com> References: <1387545625-19240-1-git-send-email-lars@metafoo.de> <52C84FC3.9010501@metafoo.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from DVREDG02.corp.atmel.com (nasmtp01.atmel.com [192.199.1.246]) by alsa0.perex.cz (Postfix) with ESMTP id BFD82261640 for ; Mon, 6 Jan 2014 04:01:48 +0100 (CET) In-Reply-To: <52C84FC3.9010501@metafoo.de> 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: Lars-Peter Clausen Cc: alsa-devel@alsa-project.org, Mark Brown , Nicolas Ferre , Liam Girdwood List-Id: alsa-devel@alsa-project.org Hi Lars, On 01/05/2014 02:15 AM, Lars-Peter Clausen wrote: > On 12/20/2013 02:20 PM, Lars-Peter Clausen wrote: >> The ASoC core assumes that the PCM component of the ASoC card transparently >> moves data around and does not impose any restrictions on the memory layout or >> the transfer speed. It ignores all fields from the snd_pcm_hardware struct for >> the PCM driver that are related to this. Setting these fields in the PCM driver >> might suggest otherwise though, so rather not set them. >> >> Signed-off-by: Lars-Peter Clausen >> Cc: Bo Shen >> Cc: Nicolas Ferre >> --- >> sound/soc/atmel/atmel-pcm-dma.c | 1 - >> sound/soc/atmel/atmel-pcm-pdc.c | 1 - >> 2 files changed, 2 deletions(-) >> >> diff --git a/sound/soc/atmel/atmel-pcm-dma.c b/sound/soc/atmel/atmel-pcm-dma.c >> index 06082e5..b79a2a8 100644 >> --- a/sound/soc/atmel/atmel-pcm-dma.c >> +++ b/sound/soc/atmel/atmel-pcm-dma.c >> @@ -50,7 +50,6 @@ static const struct snd_pcm_hardware atmel_pcm_dma_hardware = { >> SNDRV_PCM_INFO_INTERLEAVED | >> SNDRV_PCM_INFO_RESUME | >> SNDRV_PCM_INFO_PAUSE, >> - .formats = SNDRV_PCM_FMTBIT_S16_LE, > > Atmel is one of the few platforms where the formats specified for the DMA > controller are more restrictive than the formats specified for the DAI. As > the restrictions specified by the PCM part have been ignored so far I'm > wondering if this is a real restriction and things have only worked by > chance or whether the restriction should be removed? This is not a real restriction for DMA, this can be removed. Only the SSC have the restriction, and we check it in DAI driver. For this patch, Acked-by: Bo Shen > - Lars > Best Regards, Bo Shen