| Message ID | 20210310122014.28353-3-prabhakar.mahadev-lad.rj@bp.renesas.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: i2c: imx219: Trivial Fixes | expand |
Hi Prabhakar, Thank you for the patch. On Wed, Mar 10, 2021 at 12:20:13PM +0000, Lad Prabhakar wrote: > Serialize during stream start/stop in suspend/resume callbacks. Could you please explain why this is needed ? > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > --- > drivers/media/i2c/imx219.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c > index f0cf1985a4dc..87c021de1460 100644 > --- a/drivers/media/i2c/imx219.c > +++ b/drivers/media/i2c/imx219.c > @@ -1172,8 +1172,10 @@ static int __maybe_unused imx219_suspend(struct device *dev) > struct v4l2_subdev *sd = dev_get_drvdata(dev); > struct imx219 *imx219 = to_imx219(sd); > > + mutex_lock(&imx219->mutex); > if (imx219->streaming) > imx219_stop_streaming(imx219); > + mutex_unlock(&imx219->mutex); > > return 0; > } > @@ -1184,11 +1186,13 @@ static int __maybe_unused imx219_resume(struct device *dev) > struct imx219 *imx219 = to_imx219(sd); > int ret; > > + mutex_lock(&imx219->mutex); > if (imx219->streaming) { > ret = imx219_start_streaming(imx219); > if (ret) > goto error; > } > + mutex_unlock(&imx219->mutex); > > return 0; > > @@ -1197,6 +1201,7 @@ static int __maybe_unused imx219_resume(struct device *dev) > imx219->streaming = false; > __v4l2_ctrl_grab(imx219->vflip, false); > __v4l2_ctrl_grab(imx219->hflip, false); > + mutex_unlock(&imx219->mutex); > > return ret; > }
Hi Laurent, Thank you for the review. On Wed, Mar 10, 2021 at 12:40 PM Laurent Pinchart <laurent.pinchart@ideasonboard.com> wrote: > > Hi Prabhakar, > > Thank you for the patch. > > On Wed, Mar 10, 2021 at 12:20:13PM +0000, Lad Prabhakar wrote: > > Serialize during stream start/stop in suspend/resume callbacks. > > Could you please explain why this is needed ? > The streaming variable in this driver has serialized access, but this wasn't taken care during suspend/resume callbacks. Cheers, Prabhakar > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > > --- > > drivers/media/i2c/imx219.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c > > index f0cf1985a4dc..87c021de1460 100644 > > --- a/drivers/media/i2c/imx219.c > > +++ b/drivers/media/i2c/imx219.c > > @@ -1172,8 +1172,10 @@ static int __maybe_unused imx219_suspend(struct device *dev) > > struct v4l2_subdev *sd = dev_get_drvdata(dev); > > struct imx219 *imx219 = to_imx219(sd); > > > > + mutex_lock(&imx219->mutex); > > if (imx219->streaming) > > imx219_stop_streaming(imx219); > > + mutex_unlock(&imx219->mutex); > > > > return 0; > > } > > @@ -1184,11 +1186,13 @@ static int __maybe_unused imx219_resume(struct device *dev) > > struct imx219 *imx219 = to_imx219(sd); > > int ret; > > > > + mutex_lock(&imx219->mutex); > > if (imx219->streaming) { > > ret = imx219_start_streaming(imx219); > > if (ret) > > goto error; > > } > > + mutex_unlock(&imx219->mutex); > > > > return 0; > > > > @@ -1197,6 +1201,7 @@ static int __maybe_unused imx219_resume(struct device *dev) > > imx219->streaming = false; > > __v4l2_ctrl_grab(imx219->vflip, false); > > __v4l2_ctrl_grab(imx219->hflip, false); > > + mutex_unlock(&imx219->mutex); > > > > return ret; > > } > > -- > Regards, > > Laurent Pinchart
Hi Prabhakar, On Wed, Mar 10, 2021 at 12:46:39PM +0000, Lad, Prabhakar wrote: > On Wed, Mar 10, 2021 at 12:40 PM Laurent Pinchart wrote: > > On Wed, Mar 10, 2021 at 12:20:13PM +0000, Lad Prabhakar wrote: > > > Serialize during stream start/stop in suspend/resume callbacks. > > > > Could you please explain why this is needed ? > > > The streaming variable in this driver has serialized access, but this > wasn't taken care during suspend/resume callbacks. But nothing that touches the streaming variable can run concurrently to suspend/resume, isn't it ? I'm actually even quite dubious about the need to start and stop streaming during resume and suspend, the driver using the subdev should start/stop the whole video pipeline at suspend/resume time. > > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > > > --- > > > drivers/media/i2c/imx219.c | 5 +++++ > > > 1 file changed, 5 insertions(+) > > > > > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c > > > index f0cf1985a4dc..87c021de1460 100644 > > > --- a/drivers/media/i2c/imx219.c > > > +++ b/drivers/media/i2c/imx219.c > > > @@ -1172,8 +1172,10 @@ static int __maybe_unused imx219_suspend(struct device *dev) > > > struct v4l2_subdev *sd = dev_get_drvdata(dev); > > > struct imx219 *imx219 = to_imx219(sd); > > > > > > + mutex_lock(&imx219->mutex); > > > if (imx219->streaming) > > > imx219_stop_streaming(imx219); > > > + mutex_unlock(&imx219->mutex); > > > > > > return 0; > > > } > > > @@ -1184,11 +1186,13 @@ static int __maybe_unused imx219_resume(struct device *dev) > > > struct imx219 *imx219 = to_imx219(sd); > > > int ret; > > > > > > + mutex_lock(&imx219->mutex); > > > if (imx219->streaming) { > > > ret = imx219_start_streaming(imx219); > > > if (ret) > > > goto error; > > > } > > > + mutex_unlock(&imx219->mutex); > > > > > > return 0; > > > > > > @@ -1197,6 +1201,7 @@ static int __maybe_unused imx219_resume(struct device *dev) > > > imx219->streaming = false; > > > __v4l2_ctrl_grab(imx219->vflip, false); > > > __v4l2_ctrl_grab(imx219->hflip, false); > > > + mutex_unlock(&imx219->mutex); > > > > > > return ret; > > > }
Hi Laurent, On Wed, Mar 10, 2021 at 12:54 PM Laurent Pinchart <laurent.pinchart@ideasonboard.com> wrote: > > Hi Prabhakar, > > On Wed, Mar 10, 2021 at 12:46:39PM +0000, Lad, Prabhakar wrote: > > On Wed, Mar 10, 2021 at 12:40 PM Laurent Pinchart wrote: > > > On Wed, Mar 10, 2021 at 12:20:13PM +0000, Lad Prabhakar wrote: > > > > Serialize during stream start/stop in suspend/resume callbacks. > > > > > > Could you please explain why this is needed ? > > > > > The streaming variable in this driver has serialized access, but this > > wasn't taken care during suspend/resume callbacks. > > But nothing that touches the streaming variable can run concurrently to > suspend/resume, isn't it ? > You are right, we could drop this patch. > I'm actually even quite dubious about the need to start and stop > streaming during resume and suspend, the driver using the subdev should > start/stop the whole video pipeline at suspend/resume time. > I see, do we have any documentation on how bridge/subdevs should behave on suspend/resume ? I did have a quick look at the omp3isp bridge driver and it does start/stop on resume/suspend callbacks. Cheers, Prabhakar > > > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > > > > --- > > > > drivers/media/i2c/imx219.c | 5 +++++ > > > > 1 file changed, 5 insertions(+) > > > > > > > > diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c > > > > index f0cf1985a4dc..87c021de1460 100644 > > > > --- a/drivers/media/i2c/imx219.c > > > > +++ b/drivers/media/i2c/imx219.c > > > > @@ -1172,8 +1172,10 @@ static int __maybe_unused imx219_suspend(struct device *dev) > > > > struct v4l2_subdev *sd = dev_get_drvdata(dev); > > > > struct imx219 *imx219 = to_imx219(sd); > > > > > > > > + mutex_lock(&imx219->mutex); > > > > if (imx219->streaming) > > > > imx219_stop_streaming(imx219); > > > > + mutex_unlock(&imx219->mutex); > > > > > > > > return 0; > > > > } > > > > @@ -1184,11 +1186,13 @@ static int __maybe_unused imx219_resume(struct device *dev) > > > > struct imx219 *imx219 = to_imx219(sd); > > > > int ret; > > > > > > > > + mutex_lock(&imx219->mutex); > > > > if (imx219->streaming) { > > > > ret = imx219_start_streaming(imx219); > > > > if (ret) > > > > goto error; > > > > } > > > > + mutex_unlock(&imx219->mutex); > > > > > > > > return 0; > > > > > > > > @@ -1197,6 +1201,7 @@ static int __maybe_unused imx219_resume(struct device *dev) > > > > imx219->streaming = false; > > > > __v4l2_ctrl_grab(imx219->vflip, false); > > > > __v4l2_ctrl_grab(imx219->hflip, false); > > > > + mutex_unlock(&imx219->mutex); > > > > > > > > return ret; > > > > } > > -- > Regards, > > Laurent Pinchart
diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c index f0cf1985a4dc..87c021de1460 100644 --- a/drivers/media/i2c/imx219.c +++ b/drivers/media/i2c/imx219.c @@ -1172,8 +1172,10 @@ static int __maybe_unused imx219_suspend(struct device *dev) struct v4l2_subdev *sd = dev_get_drvdata(dev); struct imx219 *imx219 = to_imx219(sd); + mutex_lock(&imx219->mutex); if (imx219->streaming) imx219_stop_streaming(imx219); + mutex_unlock(&imx219->mutex); return 0; } @@ -1184,11 +1186,13 @@ static int __maybe_unused imx219_resume(struct device *dev) struct imx219 *imx219 = to_imx219(sd); int ret; + mutex_lock(&imx219->mutex); if (imx219->streaming) { ret = imx219_start_streaming(imx219); if (ret) goto error; } + mutex_unlock(&imx219->mutex); return 0; @@ -1197,6 +1201,7 @@ static int __maybe_unused imx219_resume(struct device *dev) imx219->streaming = false; __v4l2_ctrl_grab(imx219->vflip, false); __v4l2_ctrl_grab(imx219->hflip, false); + mutex_unlock(&imx219->mutex); return ret; }
Serialize during stream start/stop in suspend/resume callbacks. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> --- drivers/media/i2c/imx219.c | 5 +++++ 1 file changed, 5 insertions(+)