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| author | Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> | 2022-07-01 16:15:58 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@kernel.org> | 2022-07-15 17:21:11 +0300 |
| commit | 982c0487185bd466059ff618f398a8d074ddb654 (patch) | |
| tree | 9977ce97937c1d730c417dc50499eb95a412db1a /include/media/v4l2-subdev.h | |
| parent | dbae22e2008ee6a3acf2b7d989800eff80f0aa1f (diff) | |
| download | linux-982c0487185bd466059ff618f398a8d074ddb654.tar.xz | |
media: subdev: Add v4l2_subdev_call_state_try() macro
Add a helper macro for the situations where a non-MC driver needs to
call a state-operation (operation which takes a subdev state as a
parameter) in try-context in another subdev.
The macro allocates a new subdev state for the called subdev and frees
the state afterwards.
An example use case is a media platform driver testing if a
v4l2_subdev_format would be accepted by a source subdev.
This should not be used in MC drivers.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Tested-by: Marek Vasut <marex@denx.de>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Diffstat (limited to 'include/media/v4l2-subdev.h')
| -rw-r--r-- | include/media/v4l2-subdev.h | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index b661e1817470..9689f38a0af1 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -1434,6 +1434,40 @@ extern const struct v4l2_subdev_ops v4l2_subdev_call_wrappers; }) /** + * v4l2_subdev_call_state_try - call an operation of a v4l2_subdev which + * takes state as a parameter, passing the + * subdev a newly allocated try state. + * + * @sd: pointer to the &struct v4l2_subdev + * @o: name of the element at &struct v4l2_subdev_ops that contains @f. + * Each element there groups a set of callbacks functions. + * @f: callback function to be called. + * The callback functions are defined in groups, according to + * each element at &struct v4l2_subdev_ops. + * @args: arguments for @f. + * + * This is similar to v4l2_subdev_call_state_active(), except that as this + * version allocates a new state, this is only usable for + * V4L2_SUBDEV_FORMAT_TRY use cases. + * + * Note: only legacy non-MC drivers may need this macro. + */ +#define v4l2_subdev_call_state_try(sd, o, f, args...) \ + ({ \ + int __result; \ + static struct lock_class_key __key; \ + const char *name = KBUILD_BASENAME \ + ":" __stringify(__LINE__) ":state->lock"; \ + struct v4l2_subdev_state *state = \ + __v4l2_subdev_state_alloc(sd, name, &__key); \ + v4l2_subdev_lock_state(state); \ + __result = v4l2_subdev_call(sd, o, f, state, ##args); \ + v4l2_subdev_unlock_state(state); \ + __v4l2_subdev_state_free(state); \ + __result; \ + }) + +/** * v4l2_subdev_has_op - Checks if a subdev defines a certain operation. * * @sd: pointer to the &struct v4l2_subdev |