From 982c0487185bd466059ff618f398a8d074ddb654 Mon Sep 17 00:00:00 2001 From: Tomi Valkeinen Date: Fri, 1 Jul 2022 14:15:58 +0100 Subject: [PATCH] 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 Reviewed-by: Laurent Pinchart Reviewed-by: Hans Verkuil Tested-by: Marek Vasut Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- include/media/v4l2-subdev.h | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) 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 @@ -1433,6 +1433,40 @@ extern const struct v4l2_subdev_ops v4l2_subdev_call_wrappers; __result; \ }) +/** + * 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. *