Re: [PATCH] ASoC: amd: Changing Audio Format does not reflect.

["Agrawal, Akshu" <aagrawal2@amd.com>]

On 3/19/2020 4:52 PM, Ravulapati Vishnu vardhan rao wrote:
> When you run aplay subsequently as below by changing the stream format:
>
> aplay -Dhw:2,0 -c2 -fS16_LE -r48000 /dev/zero -vv -d 5;aplay -Dhw:2,0
> -c2 -fS24_LE -r48000 /dev/zero -vv
> as a single command, the format gets corrupted and audio does not play.
>
> So clear the ACP_(I2S/BT)TDM_ITER/IRER register when dma stops.
>
> Signed-off-by: Ravulapati Vishnu vardhan rao <Vishnuvardhanrao.Ravulapati@amd.com>
> ---
>   sound/soc/amd/raven/acp3x-i2s.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/sound/soc/amd/raven/acp3x-i2s.c b/sound/soc/amd/raven/acp3x-i2s.c
> index 3a3c47e..b07c50a 100644
> --- a/sound/soc/amd/raven/acp3x-i2s.c
> +++ b/sound/soc/amd/raven/acp3x-i2s.c
> @@ -240,9 +240,7 @@ static int acp3x_i2s_trigger(struct snd_pcm_substream *substream,
>   				reg_val = mmACP_I2STDM_IRER;
>   			}
>   		}
> -		val = rv_readl(rtd->acp3x_base + reg_val);
> -		val = val & ~BIT(0);
> -		rv_writel(val, rtd->acp3x_base + reg_val);
> +		rv_writel(0, rtd->acp3x_base + reg_val);

Clearing the entire register might result in issues.

IMO better fix is to have a sample_len mask for ITER and IRER register.

Use it to clear sample length bits in acp3x_i2s_hwparams function before 
setting the new format resolution.


Thanks,

Akshu