diff options
| author | Nicolin Chen <Guangyu.Chen@freescale.com> | 2014-07-23 13:23:39 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-07-25 19:52:35 +0200 |
| commit | c44b56af9ca3a6f135d8f22b9a240f53909b371e (patch) | |
| tree | 2f21074e058c08f5eb37b4993dfee8096927967a /sound/soc/fsl/fsl_sai.c | |
| parent | ASoC: fsl_sai: Reduce race condition during TE/RE enabling (diff) | |
| download | linux-c44b56af9ca3a6f135d8f22b9a240f53909b371e.tar.xz linux-c44b56af9ca3a6f135d8f22b9a240f53909b371e.zip | |
ASoC: fsl_sai: Don't reset FIFO until TE/RE bit is unset
TE/RE bit of T/RCSR will remain set untill the current frame is physically
finished. The FIFO reset operation should wait this bit's totally cleared
rather than ignoring its status which might cause TE/RE disabling failed.
This patch adds delay and timeout to wait for its completion before FIFO
reset.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'sound/soc/fsl/fsl_sai.c')
| -rw-r--r-- | sound/soc/fsl/fsl_sai.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index a437899d2d11..a79a9b0c08fd 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -327,7 +327,7 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd, { struct fsl_sai *sai = snd_soc_dai_get_drvdata(cpu_dai); bool tx = substream->stream == SNDRV_PCM_STREAM_PLAYBACK; - u32 xcsr; + u32 xcsr, count = 100; /* * The transmitter bit clock and frame sync are to be @@ -369,11 +369,20 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd, if (!(xcsr & FSL_SAI_CSR_FRDE)) { /* Disable both directions and reset their FIFOs */ regmap_update_bits(sai->regmap, FSL_SAI_TCSR, - FSL_SAI_CSR_TERE | FSL_SAI_CSR_FR, - FSL_SAI_CSR_FR); + FSL_SAI_CSR_TERE, 0); regmap_update_bits(sai->regmap, FSL_SAI_RCSR, - FSL_SAI_CSR_TERE | FSL_SAI_CSR_FR, - FSL_SAI_CSR_FR); + FSL_SAI_CSR_TERE, 0); + + /* TERE will remain set till the end of current frame */ + do { + udelay(10); + regmap_read(sai->regmap, FSL_SAI_xCSR(tx), &xcsr); + } while (--count && xcsr & FSL_SAI_CSR_TERE); + + regmap_update_bits(sai->regmap, FSL_SAI_TCSR, + FSL_SAI_CSR_FR, FSL_SAI_CSR_FR); + regmap_update_bits(sai->regmap, FSL_SAI_RCSR, + FSL_SAI_CSR_FR, FSL_SAI_CSR_FR); } break; default: |