diff mbox series

ASoC: fsl_audmix: Add spin lock to protect tdms

Message ID 1573025265-31852-1-git-send-email-shengjiu.wang@nxp.com
State Superseded
Headers show
Series ASoC: fsl_audmix: Add spin lock to protect tdms | expand

Commit Message

Shengjiu Wang Nov. 6, 2019, 7:27 a.m. UTC
Audmix support two substream, When two substream start
to run, the trigger function may be called by two substream
in same time, that the priv->tdms may be updated wrongly.

The expected priv->tdms is 0x3, but sometimes the
result is 0x2, or 0x1.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>

---
 sound/soc/fsl/fsl_audmix.c | 6 ++++++
 sound/soc/fsl/fsl_audmix.h | 1 +
 2 files changed, 7 insertions(+)

-- 
2.21.0

Comments

Daniel Baluta Nov. 6, 2019, 11:36 a.m. UTC | #1
Hi Shengjiu,

Comments inline.

On Wed, Nov 6, 2019 at 9:30 AM Shengjiu Wang <shengjiu.wang@nxp.com> wrote:
>

> Audmix support two substream, When two substream start

> to run, the trigger function may be called by two substream

> in same time, that the priv->tdms may be updated wrongly.

>

> The expected priv->tdms is 0x3, but sometimes the

> result is 0x2, or 0x1.

>

> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>

> ---

>  sound/soc/fsl/fsl_audmix.c | 6 ++++++

>  sound/soc/fsl/fsl_audmix.h | 1 +

>  2 files changed, 7 insertions(+)

>

> diff --git a/sound/soc/fsl/fsl_audmix.c b/sound/soc/fsl/fsl_audmix.c

> index c7e4e9757dce..a1db1bce330f 100644

> --- a/sound/soc/fsl/fsl_audmix.c

> +++ b/sound/soc/fsl/fsl_audmix.c

> @@ -286,6 +286,7 @@ static int fsl_audmix_dai_trigger(struct snd_pcm_substream *substream, int cmd,

>                                   struct snd_soc_dai *dai)

>  {

>         struct fsl_audmix *priv = snd_soc_dai_get_drvdata(dai);

> +       unsigned long lock_flags;

>

>         /* Capture stream shall not be handled */

>         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)

> @@ -295,12 +296,16 @@ static int fsl_audmix_dai_trigger(struct snd_pcm_substream *substream, int cmd,

>         case SNDRV_PCM_TRIGGER_START:

>         case SNDRV_PCM_TRIGGER_RESUME:

>         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:

> +               spin_lock_irqsave(&priv->lock, lock_flags);


Why do we need to disable interrupts here? I assume that lock is only
used in process context.

thanks,
Daniel.
Nicolin Chen Nov. 9, 2019, 2:45 a.m. UTC | #2
On Wed, Nov 06, 2019 at 03:27:45PM +0800, Shengjiu Wang wrote:
> Audmix support two substream, When two substream start

> to run, the trigger function may be called by two substream

> in same time, that the priv->tdms may be updated wrongly.

> 

> The expected priv->tdms is 0x3, but sometimes the

> result is 0x2, or 0x1.


Feels like a bug fix to me, so  might be better to have a "Fixes"
line and CC stable tree?

Anyway, change looks good to me:

Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>


Thanks

> Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>

> ---

>  sound/soc/fsl/fsl_audmix.c | 6 ++++++

>  sound/soc/fsl/fsl_audmix.h | 1 +

>  2 files changed, 7 insertions(+)

> 

> diff --git a/sound/soc/fsl/fsl_audmix.c b/sound/soc/fsl/fsl_audmix.c

> index c7e4e9757dce..a1db1bce330f 100644

> --- a/sound/soc/fsl/fsl_audmix.c

> +++ b/sound/soc/fsl/fsl_audmix.c

> @@ -286,6 +286,7 @@ static int fsl_audmix_dai_trigger(struct snd_pcm_substream *substream, int cmd,

>  				  struct snd_soc_dai *dai)

>  {

>  	struct fsl_audmix *priv = snd_soc_dai_get_drvdata(dai);

> +	unsigned long lock_flags;

>  

>  	/* Capture stream shall not be handled */

>  	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)

> @@ -295,12 +296,16 @@ static int fsl_audmix_dai_trigger(struct snd_pcm_substream *substream, int cmd,

>  	case SNDRV_PCM_TRIGGER_START:

>  	case SNDRV_PCM_TRIGGER_RESUME:

>  	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:

> +		spin_lock_irqsave(&priv->lock, lock_flags);

>  		priv->tdms |= BIT(dai->driver->id);

> +		spin_unlock_irqrestore(&priv->lock, lock_flags);

>  		break;

>  	case SNDRV_PCM_TRIGGER_STOP:

>  	case SNDRV_PCM_TRIGGER_SUSPEND:

>  	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:

> +		spin_lock_irqsave(&priv->lock, lock_flags);

>  		priv->tdms &= ~BIT(dai->driver->id);

> +		spin_unlock_irqrestore(&priv->lock, lock_flags);

>  		break;

>  	default:

>  		return -EINVAL;

> @@ -491,6 +496,7 @@ static int fsl_audmix_probe(struct platform_device *pdev)

>  		return PTR_ERR(priv->ipg_clk);

>  	}

>  

> +	spin_lock_init(&priv->lock);

>  	platform_set_drvdata(pdev, priv);

>  	pm_runtime_enable(dev);

>  

> diff --git a/sound/soc/fsl/fsl_audmix.h b/sound/soc/fsl/fsl_audmix.h

> index 7812ffec45c5..479f05695d53 100644

> --- a/sound/soc/fsl/fsl_audmix.h

> +++ b/sound/soc/fsl/fsl_audmix.h

> @@ -96,6 +96,7 @@ struct fsl_audmix {

>  	struct platform_device *pdev;

>  	struct regmap *regmap;

>  	struct clk *ipg_clk;

> +	spinlock_t lock; /* Protect tdms */

>  	u8 tdms;

>  };

>  

> -- 

> 2.21.0

>
Shengjiu Wang Nov. 11, 2019, 7:37 a.m. UTC | #3
Hi

On Sat, Nov 9, 2019 at 10:48 AM Nicolin Chen <nicoleotsuka@gmail.com> wrote:
>

> On Wed, Nov 06, 2019 at 03:27:45PM +0800, Shengjiu Wang wrote:

> > Audmix support two substream, When two substream start

> > to run, the trigger function may be called by two substream

> > in same time, that the priv->tdms may be updated wrongly.

> >

> > The expected priv->tdms is 0x3, but sometimes the

> > result is 0x2, or 0x1.

>

> Feels like a bug fix to me, so  might be better to have a "Fixes"

> line and CC stable tree?

>

> Anyway, change looks good to me:

>

> Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>

>


Ok, will send v2.

best regards
wang shengjiu
diff mbox series

Patch

diff --git a/sound/soc/fsl/fsl_audmix.c b/sound/soc/fsl/fsl_audmix.c
index c7e4e9757dce..a1db1bce330f 100644
--- a/sound/soc/fsl/fsl_audmix.c
+++ b/sound/soc/fsl/fsl_audmix.c
@@ -286,6 +286,7 @@  static int fsl_audmix_dai_trigger(struct snd_pcm_substream *substream, int cmd,
 				  struct snd_soc_dai *dai)
 {
 	struct fsl_audmix *priv = snd_soc_dai_get_drvdata(dai);
+	unsigned long lock_flags;
 
 	/* Capture stream shall not be handled */
 	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
@@ -295,12 +296,16 @@  static int fsl_audmix_dai_trigger(struct snd_pcm_substream *substream, int cmd,
 	case SNDRV_PCM_TRIGGER_START:
 	case SNDRV_PCM_TRIGGER_RESUME:
 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		spin_lock_irqsave(&priv->lock, lock_flags);
 		priv->tdms |= BIT(dai->driver->id);
+		spin_unlock_irqrestore(&priv->lock, lock_flags);
 		break;
 	case SNDRV_PCM_TRIGGER_STOP:
 	case SNDRV_PCM_TRIGGER_SUSPEND:
 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		spin_lock_irqsave(&priv->lock, lock_flags);
 		priv->tdms &= ~BIT(dai->driver->id);
+		spin_unlock_irqrestore(&priv->lock, lock_flags);
 		break;
 	default:
 		return -EINVAL;
@@ -491,6 +496,7 @@  static int fsl_audmix_probe(struct platform_device *pdev)
 		return PTR_ERR(priv->ipg_clk);
 	}
 
+	spin_lock_init(&priv->lock);
 	platform_set_drvdata(pdev, priv);
 	pm_runtime_enable(dev);
 
diff --git a/sound/soc/fsl/fsl_audmix.h b/sound/soc/fsl/fsl_audmix.h
index 7812ffec45c5..479f05695d53 100644
--- a/sound/soc/fsl/fsl_audmix.h
+++ b/sound/soc/fsl/fsl_audmix.h
@@ -96,6 +96,7 @@  struct fsl_audmix {
 	struct platform_device *pdev;
 	struct regmap *regmap;
 	struct clk *ipg_clk;
+	spinlock_t lock; /* Protect tdms */
 	u8 tdms;
 };