6.6-stable review patch. If anyone has any objections, please let me know.
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From: Tomi Valkeinen tomi.valkeinen@ideasonboard.com
[ Upstream commit 1d7804281df3f09f0a109d00406e859a00bae7ae ]
call_s_stream() uses sd->enabled_streams to track whether streaming has already been enabled. However, v4l2_subdev_enable/disable_streams_fallback(), which was the original user of this field, already uses it, and v4l2_subdev_enable/disable_streams_fallback() will call call_s_stream().
This leads to a conflict as both functions set the field. Afaics, both functions set the field to the same value, so it won't cause a runtime bug, but it's still wrong and if we, e.g., change how v4l2_subdev_enable/disable_streams_fallback() operates we might easily cause bugs.
Fix this by adding a new field, 's_stream_enabled', for call_s_stream().
Reviewed-by: Umang Jain umang.jain@ideasonboard.com Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Tested-by: Umang Jain umang.jain@ideasonboard.com Signed-off-by: Tomi Valkeinen tomi.valkeinen@ideasonboard.com Signed-off-by: Sakari Ailus sakari.ailus@linux.intel.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Stable-dep-of: 36cef585e2a3 ("media: vimc: skip .s_stream() for stopped entities") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/v4l2-core/v4l2-subdev.c | 8 ++------ include/media/v4l2-subdev.h | 3 +++ 2 files changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c index a32ef739eb449..8bfbe9d5fe3c4 100644 --- a/drivers/media/v4l2-core/v4l2-subdev.c +++ b/drivers/media/v4l2-core/v4l2-subdev.c @@ -363,12 +363,8 @@ static int call_s_stream(struct v4l2_subdev *sd, int enable) * The .s_stream() operation must never be called to start or stop an * already started or stopped subdev. Catch offenders but don't return * an error yet to avoid regressions. - * - * As .s_stream() is mutually exclusive with the .enable_streams() and - * .disable_streams() operation, we can use the enabled_streams field - * to store the subdev streaming state. */ - if (WARN_ON(!!sd->enabled_streams == !!enable)) + if (WARN_ON(sd->s_stream_enabled == !!enable)) return 0;
ret = sd->ops->video->s_stream(sd, enable); @@ -379,7 +375,7 @@ static int call_s_stream(struct v4l2_subdev *sd, int enable) }
if (!ret) { - sd->enabled_streams = enable ? BIT(0) : 0; + sd->s_stream_enabled = enable;
#if IS_REACHABLE(CONFIG_LEDS_CLASS) if (!IS_ERR_OR_NULL(sd->privacy_led)) { diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index ab2a7ef61d420..ee570dfbd791d 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -1042,6 +1042,8 @@ struct v4l2_subdev_platform_data { * v4l2_subdev_enable_streams() and * v4l2_subdev_disable_streams() helper functions for fallback * cases. + * @s_stream_enabled: Tracks whether streaming has been enabled with s_stream. + * This is only for call_s_stream() internal use. * * Each instance of a subdev driver should create this struct, either * stand-alone or embedded in a larger struct. @@ -1090,6 +1092,7 @@ struct v4l2_subdev { */ struct v4l2_subdev_state *active_state; u64 enabled_streams; + bool s_stream_enabled; };