> On 27.04.2016, at 15:26, Matthias Reichl <hias@xxxxxxxxx> wrote: > > The bcm2835-i2s driver already has support for the S16_LE format but > that format hasn't been made available because dmaengine_pcm didn't > support packed data transfers. > > bcm2835-i2s needs 16-bit left+right channel data to be packed into > a 32-bit word, the FIFO register is 32-bit only and doesn't support > 16-bit access. > > Now that dmaengine_pcm supports packed transfers the format can > be made available by setting the SND_DMAENGINE_PCM_DAI_FLAG_PACK flag. > > No further configuration is necessary: > - snd_dmaengine_dai_dma_data.addr_width is already set to > DMA_SLAVE_BUSWIDTH_4_BYTES to force 32-bit DMA transfers > - dmaengine_pcm will pick up the S16_LE format from the DAI > configuration and make it available since it's no longer > masked out due to the PACK flag. > - there are no further corner cases to catch in hw_params, > since the channel count is fixed at 2 we always have two > 16-bit stereo samples that can be transferred via 32-bit DMA > > Signed-off-by: Matthias Reichl <hias@xxxxxxxxx> Tested-by: Martin Sperl <kernel@xxxxxxxxxxxxxxxx> _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
