The len_routes field is used to tell the size of the routes array in
struct v4l2_subdev_routing. This way the number of routes returned from
S_ROUTING IOCTL may be larger than the number of routes provided, in case
there are more routes returned by the driver.

Note that this uAPI is still disabled in the code, so this change can
safely be done. Anyone who manually patched the code to enable this uAPI
must update their code.

The patch also increases the number of reserved fields in struct
v4l2_subdev_routing.

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

Add two new functions, v4l2_subdev_lock_states() and
v4l2_subdev_unclock_states(), to acquire and release the state of two
sub-devices. They differ from calling v4l2_subdev_{un,}lock_state() so
that if the two states share the same lock, the lock is acquired only
once.

Also use the new functions in v4l2_subdev_link_validate().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Julien Massot <julien.massot@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

After the conversion of dv timing calls to use a pad argument is done,
remove the old callbacks. Update the subdev ioctl handlers to use the
new callbacks.

Signed-off-by: Paweł Anikiel <panikiel@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Currently, subdev dv timing calls (i.e. g/s/query_dv_timings) are video
ops without a pad argument. This is a problem if the subdevice can have
different dv timings for each pad (e.g. a DisplayPort receiver with
multiple virtual channels).

To solve this, change these calls to include a pad argument, and put
them into pad ops. Keep the old ones temporarily to make the switch
easier.

Signed-off-by: Paweł Anikiel <panikiel@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Subdev states store all standard pad configuration data, except for
frame intervals. Fix it by adding interval fields in the
v4l2_subdev_pad_config and v4l2_subdev_stream_config structures, with
corresponding accessor functions and a helper function to implement the
.get_frame_interval() operation.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

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>

The subdev state locking macros and macros to get the active state are
currently behind CONFIG_MEDIA_CONTROLLER. This makes sense, as there can
be no subdev state without MC.

However, we have code paths common to MC and non-MC cases which call
subdev operations that have subdev state as a parameter. In the non-MC
case the state parameter would always be NULL.

Thus it makes sense to allow, e.g.:

v4l2_subdev_call_state_active(sd, pad, get_fmt, fmt)

which for non-MC case would call the subdev passing NULL as the state.

This currently fails:
https://lore.kernel.org/oe-kbuild-all/202312061101.PLrz5NnJ-lkp@intel.com/

Fix the issue by moving the related macros to be outside
CONFIG_MEDIA_CONTROLLER. The v4l2_subdev_lock_state() and
v4l2_subdev_unlock_state() macros will crash if given NULL as the state,
but the other macros behave correctly even when there's no active state,
and they will only call the lock/unlock macros if there is a state.

An alternative fix would be to make another version of
v4l2_subdev_call_state_try() with ifdefs, which would not use any state
macros and would always pass NULL as the state. But having two version
of a macro/function is always more confusing than having just one, so I
went this way.

So, this fixes the v4l2_subdev_call_state_active() macro. But we also
have v4l2_subdev_call_state_try(). It would be possible to fix that
macro by additionally creating "no-op" variants of the state alloc and
free functions. However, v4l2_subdev_call_state_try() is only used by a
single driver (stm32-dcmi), which selects MC, and the macro is supposed
to be removed as soon as the users have been converted away from the
macro. Thus I have not touched the state alloc/free functions, and I
think it makes sense to keep alloc/free functions available only if
there's actually something that can be allocated or freed.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Link: https://lore.kernel.org/r/20231208-v4l2-state-mc-fix-v1-1-a0c8162557c6@ideasonboard.com
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

The subdev .init_cfg() operation is affected by two issues:

- It has long been extended to initialize a whole v4l2_subdev_state
  instead of just a v4l2_subdev_pad_config, but its name has stuck
  around.

- Despite operating on a whole subdev state and not being directly
  exposed to the subdev users (either in-kernel or through the userspace
  API), .init_cfg() is categorized as a subdev pad operation.

This participates in making the subdev API confusing for new developers.
Fix it by renaming the operation to .init_state(), and make it a subdev
internal operation.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Michael Riesch <michael.riesch@wolfvision.net> # for imx415
Acked-by: Shuah Khan <skhan@linuxfoundation.org> # for vimc
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
[Sakari Ailus: Resolved a conflict in Renesas vsp1 driver.]
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Remove stream-unaware sub-device state access functions and macros. These
are no longer used.

[Sakari Ailus: Resolve a minor conflict in removed code.]

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Compile sub-device state information access functions
v4l2_subdev_state_get_{format,crop,compose} unconditionally as they are
now also used by plain V4L2 drivers.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>