[PATCH] ASoC: fsl_sai: Fix channel swap issue on i.MX8MP

Shengjiu Wang posted 1 patch 2 years ago
There is a newer version of this series
sound/soc/fsl/fsl_sai.c | 3 +++
1 file changed, 3 insertions(+)
[PATCH] ASoC: fsl_sai: Fix channel swap issue on i.MX8MP
Posted by Shengjiu Wang 2 years ago
When flag mclk_with_tere and mclk_direction_output enabled,
The SAI transmitter or receiver will be enabled in very early
stage, that if FSL_SAI_xMR is set by previous case,
for example previous case is one channel, current case is
two channels, then current case started with wrong xMR in
the beginning, then channel swap happen.

The patch is to clear xMR in hw_free() to avoid such
channel swap issue.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
 sound/soc/fsl/fsl_sai.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c
index 32bbe5056a63..546bd4e333b5 100644
--- a/sound/soc/fsl/fsl_sai.c
+++ b/sound/soc/fsl/fsl_sai.c
@@ -714,6 +714,9 @@ static int fsl_sai_hw_free(struct snd_pcm_substream *substream,
 	bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
 	unsigned int ofs = sai->soc_data->reg_offset;
 
+	/* Clear xMR to avoid channel swap with mclk_with_tere enabled case */
+	regmap_write(sai->regmap, FSL_SAI_xMR(tx), 0);
+
 	regmap_update_bits(sai->regmap, FSL_SAI_xCR3(tx, ofs),
 			   FSL_SAI_CR3_TRCE_MASK, 0);
 
-- 
2.34.1
Re: [PATCH] ASoC: fsl_sai: Fix channel swap issue on i.MX8MP
Posted by Fabio Estevam 2 years ago
On Mon, Dec 18, 2023 at 7:10 AM Shengjiu Wang <shengjiu.wang@nxp.com> wrote:
>
> When flag mclk_with_tere and mclk_direction_output enabled,
> The SAI transmitter or receiver will be enabled in very early
> stage, that if FSL_SAI_xMR is set by previous case,
> for example previous case is one channel, current case is
> two channels, then current case started with wrong xMR in
> the beginning, then channel swap happen.
>
> The patch is to clear xMR in hw_free() to avoid such
> channel swap issue.
>
> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>

Fixes tag, please.