[RFC PATCH v1 0/4] media: v4l2-subdev: Improve frame interval handling

Laurent Pinchart
2023-10-24T00:51:27Z

Hello,

This patch series improves frame interval handling in the V4L2 subdev
in-kernel and userspace APIs.

Frame interval are exposed to userspace on pads and streams, but the
frame interval handling is currently implemented through a v4l2_subdev
video operation, without involving the subdev state. This makes frame
intervals a second class citizen compared to formats and selection
rectangles.

Patch 1/4 starts by addressing the first issue, namely the frame
interval operations being video ops. This requires touching all the
drivers using frame intervals.

Patch 2/4 then adds a 'which' field to the subdev frame interval
userspace API, allowing frame intervals to be tried the same way formats
and selection rectangles can. Again, the same drivers need to be touched
to preserve their current behaviour.

Patch 3/4 adds support for storing the frame interval in the subdev
state, alongside the formats and selection rectangles, with similar
accessors and helper functions.

Finally, patch 4/4 demonstrates how this is used in drivers, with the
thp7312 driver serving as an example. This driver isn't upstream yet,
the latest version can be found on the linux-media mailing list ([1]).

Sakari, these patches conflict with your "[PATCH v3 0/8] Unify
sub-device state access functions" series. I plan to rebase on top once
it reaches the media tree. This shouldn't prevent reviewing this RFC in
the meantime :-)

[1] https://lore.kernel.org/linux-media/20231017132103.9914-1-laurent.pinchart@ideasonboard.com/

Laurent Pinchart (4):
media: v4l2-subdev: Turn .[gs]_frame_interval into pad operations
media: v4l2-subdev: Add which field to struct
v4l2_subdev_frame_interval
media: v4l2-subdev: Store frame interval in subdev state
media: i2c: thp7312: Store frame interval in subdev state

.../media/v4l/vidioc-subdev-g-client-cap.rst | 5 +
.../v4l/vidioc-subdev-g-frame-interval.rst | 17 +-
drivers/media/i2c/adv7180.c | 10 +-
drivers/media/i2c/et8ek8/et8ek8_driver.c | 12 +-
drivers/media/i2c/imx214.c | 12 +-
drivers/media/i2c/imx274.c | 54 +++----
drivers/media/i2c/max9286.c | 20 ++-
drivers/media/i2c/mt9m111.c | 20 ++-
drivers/media/i2c/mt9m114.c | 20 ++-
drivers/media/i2c/mt9v011.c | 24 +--
drivers/media/i2c/mt9v111.c | 22 ++-
drivers/media/i2c/ov2680.c | 10 +-
drivers/media/i2c/ov5640.c | 22 ++-
drivers/media/i2c/ov5648.c | 62 ++++----
drivers/media/i2c/ov5693.c | 10 +-
drivers/media/i2c/ov6650.c | 22 ++-
drivers/media/i2c/ov7251.c | 12 +-
drivers/media/i2c/ov7670.c | 22 +--
drivers/media/i2c/ov772x.c | 20 ++-
drivers/media/i2c/ov7740.c | 40 ++---
drivers/media/i2c/ov8865.c | 54 ++++---
drivers/media/i2c/ov9650.c | 20 ++-
drivers/media/i2c/s5c73m3/s5c73m3-core.c | 20 ++-
drivers/media/i2c/s5k5baf.c | 26 ++--
drivers/media/i2c/thp7312.c | 145 ++++++++++--------
drivers/media/i2c/tvp514x.c | 33 ++--
drivers/media/usb/em28xx/em28xx-video.c | 6 +-
drivers/media/v4l2-core/v4l2-common.c | 8 +-
drivers/media/v4l2-core/v4l2-subdev.c | 120 +++++++++++----
.../media/atomisp/i2c/atomisp-gc0310.c | 10 +-
.../media/atomisp/i2c/atomisp-gc2235.c | 10 +-
.../media/atomisp/i2c/atomisp-mt9m114.c | 10 +-
.../media/atomisp/i2c/atomisp-ov2722.c | 10 +-
.../staging/media/atomisp/pci/atomisp_cmd.c | 4 +-
.../staging/media/atomisp/pci/atomisp_ioctl.c | 4 +-
drivers/staging/media/imx/imx-ic-prp.c | 20 ++-
drivers/staging/media/imx/imx-ic-prpencvf.c | 20 ++-
drivers/staging/media/imx/imx-media-capture.c | 6 +-
drivers/staging/media/imx/imx-media-csi.c | 20 ++-
drivers/staging/media/imx/imx-media-vdic.c | 20 ++-
drivers/staging/media/tegra-video/csi.c | 12 +-
include/media/v4l2-common.h | 4 +-
include/media/v4l2-subdev.h | 79 ++++++++--
include/uapi/linux/v4l2-subdev.h | 13 +-
44 files changed, 706 insertions(+), 404 deletions(-)