| Message ID | 20240822154531.25912-4-laurent.pinchart+renesas@ideasonboard.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | media: v4l2: Improve media link validation | expand |
Hi, On 22/08/2024 18:45, Laurent Pinchart wrote: > The v4l2_subdev_link_validate() function is a helper designed to > validate links whose sink is a subdev. When called on a link whose sink > is a video device, it only prints a warning and returns. Its usage in > the sun4i_csi driver is wrong, leaving the link from the sub4i_csi > subdev to the capture video device unvalidated. > > Planned improvements to the v4l2_subdev_link_validate() function will > turn the warning into an error, breaking the sun4i_csi driver. As an > interim measure, move the warning to the sun4i_csi driver in a custom > validation handler, and drop the call to the helper. > > Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> > Acked-by: Chen-Yu Tsai <wens@csie.org> > --- > drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c > index dbb26c7b2f8d..d07e980aba61 100644 > --- a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c > +++ b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c > @@ -35,8 +35,15 @@ struct sun4i_csi_traits { > bool has_isp; > }; > > +static int sun4i_csi_video_link_validate(struct media_link *link) > +{ > + dev_warn_once(link->graph_obj.mdev->dev, > + "Driver bug: link validation not implemented\n"); > + return 0; > +} > + > static const struct media_entity_operations sun4i_csi_video_entity_ops = { > - .link_validate = v4l2_subdev_link_validate, > + .link_validate = sun4i_csi_video_link_validate, > }; > > static const struct media_entity_operations sun4i_csi_subdev_entity_ops = { I fear this might just leave it broken, but I don't have a better idea. Reviewed-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com> Tomi
On Mon, Aug 26, 2024 at 02:04:44PM +0300, Tomi Valkeinen wrote: > On 22/08/2024 18:45, Laurent Pinchart wrote: > > The v4l2_subdev_link_validate() function is a helper designed to > > validate links whose sink is a subdev. When called on a link whose sink > > is a video device, it only prints a warning and returns. Its usage in > > the sun4i_csi driver is wrong, leaving the link from the sub4i_csi > > subdev to the capture video device unvalidated. > > > > Planned improvements to the v4l2_subdev_link_validate() function will > > turn the warning into an error, breaking the sun4i_csi driver. As an > > interim measure, move the warning to the sun4i_csi driver in a custom > > validation handler, and drop the call to the helper. > > > > Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> > > Acked-by: Chen-Yu Tsai <wens@csie.org> > > --- > > drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c | 9 ++++++++- > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c > > index dbb26c7b2f8d..d07e980aba61 100644 > > --- a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c > > +++ b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c > > @@ -35,8 +35,15 @@ struct sun4i_csi_traits { > > bool has_isp; > > }; > > > > +static int sun4i_csi_video_link_validate(struct media_link *link) > > +{ > > + dev_warn_once(link->graph_obj.mdev->dev, > > + "Driver bug: link validation not implemented\n"); > > + return 0; > > +} > > + > > static const struct media_entity_operations sun4i_csi_video_entity_ops = { > > - .link_validate = v4l2_subdev_link_validate, > > + .link_validate = sun4i_csi_video_link_validate, > > }; > > > > static const struct media_entity_operations sun4i_csi_subdev_entity_ops = { > > I fear this might just leave it broken, but I don't have a better idea. I think it would be fairly easy to implement support for proper validation in the driver, but it would require access to a device for testing. This patch doesn't worsen the issue, or make fixing it more difficult, so I think it's OK for now until someone can send a real fix. > Reviewed-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
diff --git a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c index dbb26c7b2f8d..d07e980aba61 100644 --- a/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c +++ b/drivers/media/platform/sunxi/sun4i-csi/sun4i_csi.c @@ -35,8 +35,15 @@ struct sun4i_csi_traits { bool has_isp; }; +static int sun4i_csi_video_link_validate(struct media_link *link) +{ + dev_warn_once(link->graph_obj.mdev->dev, + "Driver bug: link validation not implemented\n"); + return 0; +} + static const struct media_entity_operations sun4i_csi_video_entity_ops = { - .link_validate = v4l2_subdev_link_validate, + .link_validate = sun4i_csi_video_link_validate, }; static const struct media_entity_operations sun4i_csi_subdev_entity_ops = {