media: i2c: alvium: fix req_fr check in alvium_s_frame_interval()

req_fr check in alvium_s_frame_interval() is incorrect. In particular
req_fr can't be >=max and <= min at the same time. Ensure the requested
frame rate remains within the supported range between min_fr and max_fr by
clamping it.

Also remove the unused dft_fr argument of alvium_get_frame_interval().

Signed-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: i2c: alvium: store frame interval in subdev state

Use the newly added storage for frame interval in the subdev state to
simplify the driver.

Signed-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: i2c: alvium: inline set_frame_interval into s_frame_interval

Inline alvium_set_frame_interval() into alvium_s_frame_interval().
The alvium_set_frame_interval() is called once only, by
alvium_s_frame_interval(). The latter is a thin wrapper around the
former. Inline the function in its caller to make the code more
readable.

Signed-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: i2c: alvium: remove the fr field of the alvium_dev structure

The fr (frame rate) field of the alvium_dev structure is
only used to pass result from alvium_set_frame_interval() to
alvium_set_frame_rate() that writes this info into the hw reg.
Replace it with a function parameter.

Signed-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: i2c: alvium: removal of dft_fr, min_fr and max_fr

The dft_fr, min_fr and max_fr fields of the alvium_dev structure are
only used to pass results from alvium_get_frame_interval() to its
caller. Replace them with function parameters.

Signed-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: v4l2-subdev: Fix spelling mistake "heigth" -> "height"

There is a spelling mistake in a dev_err error message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: v4l2-subdev: Add which field to struct v4l2_subdev_frame_interval

Due to a historical mishap, the v4l2_subdev_frame_interval structure
is the only part of the V4L2 subdev userspace API that doesn't contain a
'which' field. This prevents trying frame intervals using the subdev
'TRY' state mechanism.

Adding a 'which' field is simple as the structure has 8 reserved fields.
This would however break userspace as the field is currently set to 0,
corresponding to V4L2_SUBDEV_FORMAT_TRY, while the corresponding ioctls
currently operate on the 'ACTIVE' state. We thus need to add a new
subdev client cap, V4L2_SUBDEV_CLIENT_CAP_INTERVAL_USES_WHICH, to
indicate that userspace is aware of this new field.

All drivers that implement the subdev .get_frame_interval() and
.set_frame_interval() operations are updated to return -EINVAL when
operating on the TRY state, preserving the current behaviour.

While at it, fix a bad copy&paste in the documentation of the struct
v4l2_subdev_frame_interval_enum 'which' field.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> # for imx-media
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for tegra-video
Reviewed-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: v4l2-subdev: Turn .[gs]_frame_interval into pad operations

The subdev .[gs]_frame_interval are video operations, but they operate
on pads (and even on streams). Not only is this confusing, it causes
practical issues for drivers as the operations don't receive a subdev
state pointer, requiring manual state handling.

To improve the situation, turn the operations into pad operations, and
extend them to receive a state pointer like other pad operations.

While at it, rename the operations to .[gs]et_frame_interval at the same
time to match the naming scheme of other pad operations. This isn't
strictly necessary, but given that all drivers using those operations
need to be modified, handling the rename separately would generate more
churn for very little gain (if at all).

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> # for imx-media
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for tegra-video
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

media: i2c: Add support for alvium camera

The Alvium camera is shipped with sensor + isp in the same housing.
The camera can be equipped with one out of various sensor and abstract
the user from this. Camera is connected via MIPI CSI-2.

Most of the camera module features are supported, with the main exception
being fw update.

The driver provides all mandatory, optional and recommended V4L2 controls
for maximum compatibility with libcamera

References:
- https://www.alliedvision.com/en/products/embedded-vision-solutions

Signed-off-by: Tommaso Merciai <tomm.merciai@gmail.com>
[Sakari Ailus: Assign ret before using it in probe and squash Tommaso's
other fixes.]
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil: alvium-csi2.h: SPDX must use /* */ instead of //]