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| author | Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> | 2024-06-19 02:56:01 +0300 |
|---|---|---|
| committer | Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> | 2024-08-26 16:36:14 +0300 |
| commit | d1307671e5221967809c4b626affbad29e371006 (patch) | |
| tree | ac9272d205436d4da9ab577f84e94c9a95546f91 /drivers/media/v4l2-core | |
| parent | 9bde4f7caf38df94257d2483e89f371b1a530e9a (diff) | |
| download | linux-stable-d1307671e5221967809c4b626affbad29e371006.tar.gz linux-stable-d1307671e5221967809c4b626affbad29e371006.tar.bz2 linux-stable-d1307671e5221967809c4b626affbad29e371006.zip | |
media: v4l2-subdev: Refactor warnings in v4l2_subdev_link_validate()
The v4l2_subdev_link_validate() function prints a one-time warning if it
gets called on a link whose source or sink is not a subdev. As links get
validated in the context of their sink, a call to the helper when the
link's sink is not a subdev indicates that the driver has set its
.link_validate() handler to v4l2_subdev_link_validate() on a non-subdev
entity, which is a clear driver bug. On the other hand, the link's
source not being a subdev indicates that the helper is used for a subdev
connected to a video output device, which is a lesser issue, if only
because this is currently common practice.
There are no drivers left in the kernel that use
v4l2_subdev_link_validate() in a context where it may get called on a
non-subdev sink. Replace the pr_warn_once() with a WARN_ON_ONCE() in
this case to make sure that new offenders won't be introduced.
A subsequent change will improve the v4l2_subdev_link_validate() helper
to properly support validating video device to subdev links.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Diffstat (limited to 'drivers/media/v4l2-core')
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-subdev.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index 7c5812d55315..d3196042d5c5 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -1443,11 +1443,15 @@ int v4l2_subdev_link_validate(struct media_link *link) bool states_locked; int ret; - if (!is_media_entity_v4l2_subdev(link->sink->entity) || - !is_media_entity_v4l2_subdev(link->source->entity)) { - pr_warn_once("%s of link '%s':%u->'%s':%u is not a V4L2 sub-device, driver bug!\n", - !is_media_entity_v4l2_subdev(link->sink->entity) ? - "sink" : "source", + /* + * Links are validated in the context of the sink entity. Usage of this + * helper on a sink that is not a subdev is a clear driver bug. + */ + if (WARN_ON_ONCE(!is_media_entity_v4l2_subdev(link->sink->entity))) + return -EINVAL; + + if (!is_media_entity_v4l2_subdev(link->source->entity)) { + pr_warn_once("source of link '%s':%u->'%s':%u is not a V4L2 sub-device, driver bug!\n", link->source->entity->name, link->source->index, link->sink->entity->name, link->sink->index); return 0; |