diff mbox series

[v2,4/4] rcar-csi2: Do not try to recover after transfer error

Message ID 20210115002148.4079591-5-niklas.soderlund+renesas@ragnatech.se (mailing list archive)
State Superseded
Delegated to: Kieran Bingham
Headers show
Series rcar-csi2: Update handling of transfer error | expand

Commit Message

Niklas Söderlund Jan. 15, 2021, 12:21 a.m. UTC
Instead of restarting the R-Car CSI-2 receiver if a transmission error
is detected inform the R-Car VIN driver of the error so it can stop the
whole pipeline and inform user-space. This is done to reflect a updated
usage recommendation in later versions of the datasheet.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---
 drivers/media/platform/rcar-vin/rcar-csi2.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

Comments

Sergei Shtylyov Jan. 15, 2021, 8:58 a.m. UTC | #1
Hello!

On 15.01.2021 3:21, Niklas Söderlund wrote:

> Instead of restarting the R-Car CSI-2 receiver if a transmission error
> is detected inform the R-Car VIN driver of the error so it can stop the
              ^ , woiuldn't hurt here?


> whole pipeline and inform user-space. This is done to reflect a updated
                                                                 ^ an

> usage recommendation in later versions of the datasheet.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
[...]

MBR, Sergei
Jacopo Mondi Jan. 15, 2021, 11:17 a.m. UTC | #2
Hi Niklas,

On Fri, Jan 15, 2021 at 01:21:48AM +0100, Niklas Söderlund wrote:
> Instead of restarting the R-Car CSI-2 receiver if a transmission error
> is detected inform the R-Car VIN driver of the error so it can stop the
> whole pipeline and inform user-space. This is done to reflect a updated
> usage recommendation in later versions of the datasheet.

I wonder if there's any userspace component that relies on the
auto-restart procedure.

>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

If this aligns the behaviour with the manual (and it seems also saner
than attemping a restart) I think it's good.

Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>

Thanks
  j

> ---
>  drivers/media/platform/rcar-vin/rcar-csi2.c | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> index 945d2eb8723367f0..a7212ecc46572a3b 100644
> --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -773,21 +773,19 @@ static irqreturn_t rcsi2_irq(int irq, void *data)
>
>  	rcsi2_write(priv, INTERRSTATE_REG, err_status);
>
> -	dev_info(priv->dev, "Transfer error, restarting CSI-2 receiver\n");
> -
>  	return IRQ_WAKE_THREAD;
>  }
>
>  static irqreturn_t rcsi2_irq_thread(int irq, void *data)
>  {
>  	struct rcar_csi2 *priv = data;
> +	struct v4l2_event event = {
> +		.type = V4L2_EVENT_EOS,
> +	};
>
> -	mutex_lock(&priv->lock);
> -	rcsi2_stop(priv);
> -	usleep_range(1000, 2000);
> -	if (rcsi2_start(priv))
> -		dev_warn(priv->dev, "Failed to restart CSI-2 receiver\n");
> -	mutex_unlock(&priv->lock);
> +	dev_err(priv->dev, "Transfer error detected.\n");
> +
> +	v4l2_subdev_notify_event(&priv->subdev, &event);
>
>  	return IRQ_HANDLED;
>  }
> --
> 2.30.0
>
Hans Verkuil Jan. 25, 2021, 9:44 a.m. UTC | #3
On 15/01/2021 01:21, Niklas Söderlund wrote:
> Instead of restarting the R-Car CSI-2 receiver if a transmission error
> is detected inform the R-Car VIN driver of the error so it can stop the
> whole pipeline and inform user-space. This is done to reflect a updated
> usage recommendation in later versions of the datasheet.
> 
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> ---
>  drivers/media/platform/rcar-vin/rcar-csi2.c | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> index 945d2eb8723367f0..a7212ecc46572a3b 100644
> --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -773,21 +773,19 @@ static irqreturn_t rcsi2_irq(int irq, void *data)
>  
>  	rcsi2_write(priv, INTERRSTATE_REG, err_status);
>  
> -	dev_info(priv->dev, "Transfer error, restarting CSI-2 receiver\n");
> -
>  	return IRQ_WAKE_THREAD;
>  }
>  
>  static irqreturn_t rcsi2_irq_thread(int irq, void *data)
>  {
>  	struct rcar_csi2 *priv = data;
> +	struct v4l2_event event = {
> +		.type = V4L2_EVENT_EOS,
> +	};
>  
> -	mutex_lock(&priv->lock);
> -	rcsi2_stop(priv);
> -	usleep_range(1000, 2000);
> -	if (rcsi2_start(priv))
> -		dev_warn(priv->dev, "Failed to restart CSI-2 receiver\n");
> -	mutex_unlock(&priv->lock);
> +	dev_err(priv->dev, "Transfer error detected.\n");

You probably want to call vb2_queue_error() here. Typically once
something like this happens you have to restart everything and marking
the queue as 'error' will ensure that VIDIOC_QBUF will return an error
until the queue is reset (STREAMOFF).

It doesn't hurt to also raise the EOS event, I'm fine with that.

Regards,

	Hans

> +
> +	v4l2_subdev_notify_event(&priv->subdev, &event);
>  
>  	return IRQ_HANDLED;
>  }
>
Niklas Söderlund March 10, 2021, 4:45 p.m. UTC | #4
Hi Hans,

Thanks for your feedback.

On 2021-01-25 10:44:48 +0100, Hans Verkuil wrote:
> On 15/01/2021 01:21, Niklas Söderlund wrote:
> > Instead of restarting the R-Car CSI-2 receiver if a transmission error
> > is detected inform the R-Car VIN driver of the error so it can stop the
> > whole pipeline and inform user-space. This is done to reflect a updated
> > usage recommendation in later versions of the datasheet.
> > 
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > ---
> >  drivers/media/platform/rcar-vin/rcar-csi2.c | 14 ++++++--------
> >  1 file changed, 6 insertions(+), 8 deletions(-)
> > 
> > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > index 945d2eb8723367f0..a7212ecc46572a3b 100644
> > --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > @@ -773,21 +773,19 @@ static irqreturn_t rcsi2_irq(int irq, void *data)
> >  
> >  	rcsi2_write(priv, INTERRSTATE_REG, err_status);
> >  
> > -	dev_info(priv->dev, "Transfer error, restarting CSI-2 receiver\n");
> > -
> >  	return IRQ_WAKE_THREAD;
> >  }
> >  
> >  static irqreturn_t rcsi2_irq_thread(int irq, void *data)
> >  {
> >  	struct rcar_csi2 *priv = data;
> > +	struct v4l2_event event = {
> > +		.type = V4L2_EVENT_EOS,
> > +	};
> >  
> > -	mutex_lock(&priv->lock);
> > -	rcsi2_stop(priv);
> > -	usleep_range(1000, 2000);
> > -	if (rcsi2_start(priv))
> > -		dev_warn(priv->dev, "Failed to restart CSI-2 receiver\n");
> > -	mutex_unlock(&priv->lock);
> > +	dev_err(priv->dev, "Transfer error detected.\n");
> 
> You probably want to call vb2_queue_error() here. Typically once
> something like this happens you have to restart everything and marking
> the queue as 'error' will ensure that VIDIOC_QBUF will return an error
> until the queue is reset (STREAMOFF).

The CSI-2 driver is a bridge driver and does not deal with buffers.  
Instead the idea here is to signal EOS so that the VIN driver (and 
user-space) can detect it and indeed as you point out deal with 
signaling vb2 error.

I will respin this series as it needs to be rebased anyhow.

> 
> It doesn't hurt to also raise the EOS event, I'm fine with that.
> 
> Regards,
> 
> 	Hans
> 
> > +
> > +	v4l2_subdev_notify_event(&priv->subdev, &event);
> >  
> >  	return IRQ_HANDLED;
> >  }
> > 
>
diff mbox series

Patch

diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
index 945d2eb8723367f0..a7212ecc46572a3b 100644
--- a/drivers/media/platform/rcar-vin/rcar-csi2.c
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -773,21 +773,19 @@  static irqreturn_t rcsi2_irq(int irq, void *data)
 
 	rcsi2_write(priv, INTERRSTATE_REG, err_status);
 
-	dev_info(priv->dev, "Transfer error, restarting CSI-2 receiver\n");
-
 	return IRQ_WAKE_THREAD;
 }
 
 static irqreturn_t rcsi2_irq_thread(int irq, void *data)
 {
 	struct rcar_csi2 *priv = data;
+	struct v4l2_event event = {
+		.type = V4L2_EVENT_EOS,
+	};
 
-	mutex_lock(&priv->lock);
-	rcsi2_stop(priv);
-	usleep_range(1000, 2000);
-	if (rcsi2_start(priv))
-		dev_warn(priv->dev, "Failed to restart CSI-2 receiver\n");
-	mutex_unlock(&priv->lock);
+	dev_err(priv->dev, "Transfer error detected.\n");
+
+	v4l2_subdev_notify_event(&priv->subdev, &event);
 
 	return IRQ_HANDLED;
 }