On Fri, Sep 13, 2019 at 10:28:05PM +0300, Daniel Baluta wrote: > From: Mihai Serban <mihai.ser...@nxp.com> > > EDMA requires the period size to be multiple of maxburst. Otherwise the > remaining bytes are not transferred and thus noise is produced. > > We can handle this issue by adding a constraint on > SNDRV_PCM_HW_PARAM_PERIOD_SIZE to be multiple of tx/rx maxburst value. > > Signed-off-by: Mihai Serban <mihai.ser...@nxp.com> > Signed-off-by: Daniel Baluta <daniel.bal...@nxp.com>
Acked-by: Nicolin Chen <nicoleots...@gmail.com> Thanks > --- > Changes since v1: > * rename variable to use_edma as per Nicolin's suggestion. > > sound/soc/fsl/fsl_sai.c | 15 +++++++++++++++ > sound/soc/fsl/fsl_sai.h | 1 + > 2 files changed, 16 insertions(+) > > diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c > index ef0b74693093..b517e4bc1b87 100644 > --- a/sound/soc/fsl/fsl_sai.c > +++ b/sound/soc/fsl/fsl_sai.c > @@ -628,6 +628,16 @@ static int fsl_sai_startup(struct snd_pcm_substream > *substream, > FSL_SAI_CR3_TRCE_MASK, > FSL_SAI_CR3_TRCE); > > + /* > + * EDMA controller needs period size to be a multiple of > + * tx/rx maxburst > + */ > + if (sai->soc_data->use_edma) > + snd_pcm_hw_constraint_step(substream->runtime, 0, > + SNDRV_PCM_HW_PARAM_PERIOD_SIZE, > + tx ? sai->dma_params_tx.maxburst : > + sai->dma_params_rx.maxburst); > + > ret = snd_pcm_hw_constraint_list(substream->runtime, 0, > SNDRV_PCM_HW_PARAM_RATE, &fsl_sai_rate_constraints); > > @@ -1026,30 +1036,35 @@ static int fsl_sai_remove(struct platform_device > *pdev) > > static const struct fsl_sai_soc_data fsl_sai_vf610_data = { > .use_imx_pcm = false, > + .use_edma = false, > .fifo_depth = 32, > .reg_offset = 0, > }; > > static const struct fsl_sai_soc_data fsl_sai_imx6sx_data = { > .use_imx_pcm = true, > + .use_edma = false, > .fifo_depth = 32, > .reg_offset = 0, > }; > > static const struct fsl_sai_soc_data fsl_sai_imx7ulp_data = { > .use_imx_pcm = true, > + .use_edma = false, > .fifo_depth = 16, > .reg_offset = 8, > }; > > static const struct fsl_sai_soc_data fsl_sai_imx8mq_data = { > .use_imx_pcm = true, > + .use_edma = false, > .fifo_depth = 128, > .reg_offset = 8, > }; > > static const struct fsl_sai_soc_data fsl_sai_imx8qm_data = { > .use_imx_pcm = true, > + .use_edma = true, > .fifo_depth = 64, > .reg_offset = 0, > }; > diff --git a/sound/soc/fsl/fsl_sai.h b/sound/soc/fsl/fsl_sai.h > index b12cb578f6d0..76b15deea80c 100644 > --- a/sound/soc/fsl/fsl_sai.h > +++ b/sound/soc/fsl/fsl_sai.h > @@ -157,6 +157,7 @@ > > struct fsl_sai_soc_data { > bool use_imx_pcm; > + bool use_edma; > unsigned int fifo_depth; > unsigned int reg_offset; > }; > -- > 2.17.1 >