STRUCT SND_DMAENGINE(9)                      PCM API                      STRUCT SND_DMAENGINE(9)



NAME
       struct_snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM

SYNOPSIS
       struct snd_dmaengine_pcm_config {
         int (* prepare_slave_config) (struct snd_pcm_substream *substream,struct snd_pcm_hw_params *params,struct dma_slave_config *slave_config);
         struct dma_chan *(* compat_request_channel) (struct snd_soc_pcm_runtime *rtd,struct snd_pcm_substream *substream);
         dma_filter_fn compat_filter_fn;
         struct device * dma_dev;
         const char * chan_names[SNDRV_PCM_STREAM_LAST + 1];
         const struct snd_pcm_hardware * pcm_hardware;
         unsigned int prealloc_buffer_size;
       };

MEMBERS
       prepare_slave_config
           Callback used to fill in the DMA slave_config for a PCM substream. Will be called from
           the PCM drivers hwparams callback.

       compat_request_channel
           Callback to request a DMA channel for platforms which do not use devicetree.

       compat_filter_fn
           Will be used as the filter function when requesting a channel for platforms which do
           not use devicetree. The filter parameter will be the DAI's DMA data.

       dma_dev
           If set, request DMA channel on this device rather than the DAI device.

       chan_names[SNDRV_PCM_STREAM_LAST + 1]
           If set, these custom DMA channel names will be requested at registration time.

       pcm_hardware
           snd_pcm_hardware struct to be used for the PCM.

       prealloc_buffer_size
           Size of the preallocated audio buffer.

NOTE
       If both compat_request_channel and compat_filter_fn are set compat_request_channel will be
       used to request the channel and compat_filter_fn will be ignored. Otherwise the channel
       will be requested using dma_request_channel with compat_filter_fn as the filter function.

COPYRIGHT
Kernel Hackers Manual 4.8.                 January 2017                   STRUCT SND_DMAENGINE(9)