From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vinod Koul Subject: Re: [PATCH 2/2] ASoC: dmaengine_pcm: add snd_dmaengine_generic_pcm_open() Date: Thu, 21 Mar 2013 15:27:18 +0530 Message-ID: <20130321095718.GO10326@intel.com> References: <1363318601-31505-1-git-send-email-shawn.guo@linaro.org> <1363318601-31505-3-git-send-email-shawn.guo@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by alsa0.perex.cz (Postfix) with ESMTP id 74B14265E4B for ; Thu, 21 Mar 2013 11:22:21 +0100 (CET) Content-Disposition: inline In-Reply-To: <1363318601-31505-3-git-send-email-shawn.guo@linaro.org> 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: Shawn Guo Cc: Markus Pargmann , alsa-devel@alsa-project.org, Mark Brown , Sebastien Guiriec , linux-arm-kernel@lists.infradead.org List-Id: alsa-devel@alsa-project.org On Fri, Mar 15, 2013 at 11:36:41AM +0800, Shawn Guo wrote: > With generic DMA device tree binding and helper function > dma_request_slave_channel() in place, dmaengine_pcm should support > that in requesting DMA channel for users that support generic DMA > device tree binding. > > Add a new API snd_dmaengine_generic_pcm_open() as the variant of > snd_dmaengine_pcm_open(). It takes DMA client struct device pointer > and slave channel name as arguments and calls generic DMA helper > dma_request_slave_channel() to request DMA channel from dmaengine. NAK This is why we have dma_request_slave_channel_compat() API. You dont need to write two open handlers here, just pass all the arguments and if DT is set it will allocate a channel using dma_request_slave_channel() otherwise will do dma_request_channel which is what you need. > > Signed-off-by: Shawn Guo > Cc: Mark Brown > Cc: alsa-devel@alsa-project.org > Reviewed-by: Arnd Bergmann > --- > include/sound/dmaengine_pcm.h | 2 ++ > sound/soc/soc-dmaengine-pcm.c | 39 +++++++++++++++++++++++++++++++++++++++ > 2 files changed, 41 insertions(+) > > diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h > index b877334..452df15 100644 > --- a/include/sound/dmaengine_pcm.h > +++ b/include/sound/dmaengine_pcm.h > @@ -43,6 +43,8 @@ snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream > > int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream, > dma_filter_fn filter_fn, void *filter_data); > +int snd_dmaengine_generic_pcm_open(struct snd_pcm_substream *substream, > + struct device *dev, const char *name); > int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream); > > struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream); > diff --git a/sound/soc/soc-dmaengine-pcm.c b/sound/soc/soc-dmaengine-pcm.c > index 111b7d92..970eb2b 100644 > --- a/sound/soc/soc-dmaengine-pcm.c > +++ b/sound/soc/soc-dmaengine-pcm.c > @@ -304,6 +304,45 @@ int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream, > EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open); > > /** > + * snd_dmaengine_generic_pcm_open - Open a dmaengine based PCM substream > + * @substream: PCM substream > + * @dev: pointer to DMA client device structure > + * @name: DMA slave channel name > + * > + * Returns 0 on success, a negative error code otherwise. > + * > + * This function is a variant of snd_dmaengine_pcm_open(). It takes different > + * parameters and calls generic DMA helper dma_request_slave_channel() to > + * request a DMA channel from dmaengine. > + */ > +int snd_dmaengine_generic_pcm_open(struct snd_pcm_substream *substream, > + struct device *dev, const char *name) > +{ > + struct dmaengine_pcm_runtime_data *prtd; > + int ret; > + > + ret = snd_pcm_hw_constraint_integer(substream->runtime, > + SNDRV_PCM_HW_PARAM_PERIODS); > + if (ret < 0) > + return ret; > + > + prtd = kzalloc(sizeof(*prtd), GFP_KERNEL); > + if (!prtd) > + return -ENOMEM; > + > + prtd->dma_chan = dma_request_slave_channel(dev, name); > + if (!prtd->dma_chan) { > + kfree(prtd); > + return -ENXIO; > + } > + > + substream->runtime->private_data = prtd; > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(snd_dmaengine_generic_pcm_open); > + > +/** > * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream > * @substream: PCM substream > */ > -- > 1.7.9.5 > >