kernel/linux.git/include/media/v4l2-subdev.h, branch v6.12.80

media: v4l2-subdev: Fix alloc failure check in v4l2_subdev_call_state_try()

2025-10-19T14:33:34+00:00

commit f37df9a0eb5e43fcfe02cbaef076123dc0d79c7e upstream. v4l2_subdev_call_state_try() macro allocates a subdev state with __v4l2_subdev_state_alloc(), but does not check the returned value. If __v4l2_subdev_state_alloc fails, it returns an ERR_PTR, and that would cause v4l2_subdev_call_state_try() to crash. Add proper error handling to v4l2_subdev_call_state_try(). Signed-off-by: Tomi Valkeinen Fixes: 982c0487185b ("media: subdev: Add v4l2_subdev_call_state_try() macro") Reported-by: Dan Carpenter Closes: https://lore.kernel.org/all/aJTNtpDUbTz7eyJc%40stanley.mountain/ Cc: stable@vger.kernel.org Reviewed-by: Dan Carpenter Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman

media: v4l: Memset argument to 0 before calling get_mbus_config pad op

2025-05-29T09:02:49+00:00

[ Upstream commit 91d6a99acfa5ce9f95ede775074b80f7193bd717 ] Memset the config argument to get_mbus_config V4L2 sub-device pad operation to zero before calling the operation. This ensures the callers don't need to bother with it nor the implementations need to set all fields that may not be relevant to them. Signed-off-by: Sakari Ailus Reviewed-by: Tomi Valkeinen Signed-off-by: Hans Verkuil Signed-off-by: Sasha Levin

media: v4l2-subdev: Support hybrid links in v4l2_subdev_link_validate()

2024-08-26T13:36:14+00:00

The v4l2_subdev_link_validate() helper function is meant to be used as a drop-in implementation of a V4L2 subdev entity .link_validate() handler. It supports subdev-to-subdev links only, and complains if one end of the link is not a subdev. This forces drivers that have video output devices connected to subdevs to implement a custom .link_validate() handler, calling v4l2_subdev_link_validate() for the subdev-to-subdev links, and performing manual link validation for the video-to-subdev links. Video devices embed a media entity, and therefore also have a .link_validate() operation. For video capture devices, the operation should be manually implemented by drivers for validate the subdev-to-video links. For video output devices, on the other hand, that operation is never called, as link validation is performed in the context of the sink entity. As a result, we end up forcing drivers to implement a custom .link_validate() handler for subdevs connected to video output devices, when the video devices provide an operation that could be used for that purpose. To improve that situation, make v4l2_subdev_link_validate() delegate link validation to the source's .link_validate() operation when the link source is a video device and the link sink is a subdev. This allows broader usage of v4l2_subdev_link_validate(), and simplifies drivers by making video device link validation easy to implement in the video device .link_validate(), regardless of whether the video device is an output device or a capture device. Signed-off-by: Laurent Pinchart Reviewed-by: Tomi Valkeinen Acked-by: Sakari Ailus

media: v4l: subdev: Fix typo in documentation

2024-06-26T06:14:03+00:00

Replace the incorrect reference to the v4l2_subdev_enable_stream() function with the correct v4l2_subdev_enable_streams() spelling. Fixes: d0749adb3070 ("media: v4l2-subdev: Add subdev .(enable|disable)_streams() operations") Reviewed-by: Tomi Valkeinen Link: https://lore.kernel.org/r/20240619225343.15873-1-laurent.pinchart@ideasonboard.com Signed-off-by: Laurent Pinchart

media: v4l2-subdev: Provide const-aware subdev state accessors

2024-06-04T06:31:25+00:00

It would be useful to mark instances of v4l2_subdev_state structures as const when code needs to access them read-only. This isn't currently possible, as the v4l2_subdev_state_get_*() accessor functions take a non-const pointer to the state. Use _Generic() to provide two different versions of the accessors, for const and non-const states respectively. The former returns a const pointer to the requested format, rectangle or interval, implementing const-correctness. The latter returns a non-const pointer, preserving the current behaviour for drivers. Signed-off-by: Laurent Pinchart Reviewed-by: Sakari Ailus Reviewed-by: Tomi Valkeinen [Sakari Ailus: Drop the word "below" from the text.] Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil

media: v4l2-subdev: Fix v4l2_subdev_state_get_format() documentation

2024-06-04T06:31:25+00:00

The documentation of the v4l2_subdev_state_get_format() macro incorrectly references __v4l2_subdev_state_get_format() instead of __v4l2_subdev_state_gen_call(). Fix it, and also update the list of similar macros to add the missing v4l2_subdev_state_get_interval(). Suggested-by: Sakari Ailus Signed-off-by: Laurent Pinchart Reviewed-by: Sakari Ailus Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil

media: subdev: Improve s_stream documentation

2024-06-04T06:31:25+00:00

Now that enable/disable_streams operations are available for single-stream subdevices too, there's no reason to use the old s_stream operation on new drivers. Extend the documentation reflecting this. Signed-off-by: Tomi Valkeinen Reviewed-by: Umang Jain Reviewed-by: Laurent Pinchart Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil

media: subdev: Add v4l2_subdev_is_streaming()

2024-06-04T06:31:24+00:00

Add a helper function which returns whether the subdevice is streaming, i.e. if .s_stream or .enable_streams has been called successfully. Reviewed-by: Umang Jain Reviewed-by: Laurent Pinchart Tested-by: Umang Jain Signed-off-by: Tomi Valkeinen Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil

media: subdev: Improve v4l2_subdev_enable/disable_streams_fallback

2024-06-04T06:31:24+00:00

v4l2_subdev_enable/disable_streams_fallback() supports falling back to .s_stream() for subdevs with a single source pad. It also tracks the enabled streams for that one pad in the sd->enabled_streams field. Tracking the enabled streams with sd->enabled_streams does not make sense, as with .s_stream() there can only be a single stream per pad. Thus, as the v4l2_subdev_enable/disable_streams_fallback() only supports a single source pad, all we really need is a boolean which tells whether streaming has been enabled on this pad or not. However, as we only need a true/false state for a pad (instead of tracking which streams have been enabled for a pad), we can easily extend the fallback mechanism to support multiple source pads as we only need to keep track of which pads have been enabled. Change the sd->enabled_streams field to sd->enabled_pads, which is a 64-bit bitmask tracking the enabled source pads. With this change we can remove the restriction that v4l2_subdev_enable/disable_streams_fallback() only supports a single source pad. Reviewed-by: Laurent Pinchart Tested-by: Umang Jain Signed-off-by: Tomi Valkeinen Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil

media: subdev: Fix use of sd->enabled_streams in call_s_stream()

2024-06-04T06:31:24+00:00

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 Reviewed-by: Laurent Pinchart Tested-by: Umang Jain Signed-off-by: Tomi Valkeinen Signed-off-by: Sakari Ailus Signed-off-by: Hans Verkuil