From: Nicolin Chen Date: Wed, 23 Jul 2014 11:23:38 +0000 (+0800) Subject: ASoC: fsl_sai: Reduce race condition during TE/RE enabling X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=f4075a8f452aff5465c6522c92da9db71ed11b7f;p=linux-beck.git ASoC: fsl_sai: Reduce race condition during TE/RE enabling For trigger start, we don't need to check if it's the first time to enable TE/RE or second time. It doesn't hurt to enable them any way, which in the meantime can reduce race condition for TE/RE enabling. For trigger stop, we will definitely clear FRDE of current direction. Thus the driver only needs to read the opposite one's. Signed-off-by: Nicolin Chen Signed-off-by: Mark Brown --- diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 1b6ee2ce849f..a437899d2d11 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 tcsr, rcsr; + u32 xcsr; /* * The transmitter bit clock and frame sync are to be @@ -338,9 +338,6 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd, regmap_update_bits(sai->regmap, FSL_SAI_RCR2, FSL_SAI_CR2_SYNC, FSL_SAI_CR2_SYNC); - regmap_read(sai->regmap, FSL_SAI_TCSR, &tcsr); - regmap_read(sai->regmap, FSL_SAI_RCSR, &rcsr); - /* * It is recommended that the transmitter is the last enabled * and the first disabled. @@ -349,12 +346,10 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd, case SNDRV_PCM_TRIGGER_START: case SNDRV_PCM_TRIGGER_RESUME: case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: - if (!(tcsr & FSL_SAI_CSR_FRDE || rcsr & FSL_SAI_CSR_FRDE)) { - regmap_update_bits(sai->regmap, FSL_SAI_RCSR, - FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); - regmap_update_bits(sai->regmap, FSL_SAI_TCSR, - FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); - } + regmap_update_bits(sai->regmap, FSL_SAI_RCSR, + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); + regmap_update_bits(sai->regmap, FSL_SAI_TCSR, + FSL_SAI_CSR_TERE, FSL_SAI_CSR_TERE); regmap_update_bits(sai->regmap, FSL_SAI_xCSR(tx), FSL_SAI_CSR_xIE_MASK, FSL_SAI_FLAGS); @@ -370,7 +365,8 @@ static int fsl_sai_trigger(struct snd_pcm_substream *substream, int cmd, FSL_SAI_CSR_xIE_MASK, 0); /* Check if the opposite FRDE is also disabled */ - if (!(tx ? rcsr & FSL_SAI_CSR_FRDE : tcsr & FSL_SAI_CSR_FRDE)) { + regmap_read(sai->regmap, FSL_SAI_xCSR(!tx), &xcsr); + 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,