Commit 09752745 authored by Hans Verkuil's avatar Hans Verkuil Committed by Mauro Carvalho Chehab
Browse files

media: v4l2-ctrls: add v4l2_ctrl_modify_dimensions 



Add a new function to modify the dimensions of an array control.

This is typically used if the array size depends on e.g. the currently
selected video format.

Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: default avatarLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent 7392d87a

drivers/media/v4l2-core/v4l2-ctrls-api.c

+36 −0
Original line number Diff line number Diff line
@@ -989,6 +989,42 @@ int __v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 
}

EXPORT_SYMBOL(__v4l2_ctrl_modify_range);



int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,

				  u32 dims[V4L2_CTRL_MAX_DIMS])

{

	unsigned int elems = 1;

	unsigned int i;

	void *p_array;



	lockdep_assert_held(ctrl->handler->lock);



	if (!ctrl->is_array || ctrl->is_dyn_array)

		return -EINVAL;



	for (i = 0; i < ctrl->nr_of_dims; i++)

		elems *= dims[i];

	if (elems == 0)

		return -EINVAL;

	p_array = kvzalloc(2 * elems * ctrl->elem_size, GFP_KERNEL);

	if (!p_array)

		return -ENOMEM;

	kvfree(ctrl->p_array);

	ctrl->p_array_alloc_elems = elems;

	ctrl->elems = elems;

	ctrl->new_elems = elems;

	ctrl->p_array = p_array;

	ctrl->p_new.p = p_array;

	ctrl->p_cur.p = p_array + elems * ctrl->elem_size;

	for (i = 0; i < ctrl->nr_of_dims; i++)

		ctrl->dims[i] = dims[i];

	for (i = 0; i < elems; i++)

		ctrl->type_ops->init(ctrl, i, ctrl->p_cur);

	cur_to_new(ctrl);

	send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_VALUE);

	return 0;

}

EXPORT_SYMBOL(__v4l2_ctrl_modify_dimensions);



/* Implement VIDIOC_QUERY_EXT_CTRL */

int v4l2_query_ext_ctrl(struct v4l2_ctrl_handler *hdl, struct v4l2_query_ext_ctrl *qc)

{

include/media/v4l2-ctrls.h

+53 −0
Original line number Diff line number Diff line
@@ -957,6 +957,59 @@ static inline int v4l2_ctrl_modify_range(struct v4l2_ctrl *ctrl, 
	return rval;

}



/**

 *__v4l2_ctrl_modify_dimensions() - Unlocked variant of v4l2_ctrl_modify_dimensions()

 *

 * @ctrl:	The control to update.

 * @dims:	The control's new dimensions.

 *

 * Update the dimensions of an array control on the fly. The elements of the

 * array are reset to their default value, even if the dimensions are

 * unchanged.

 *

 * An error is returned if @dims is invalid for this control.

 *

 * The caller is responsible for acquiring the control handler mutex on behalf

 * of __v4l2_ctrl_modify_dimensions().

 *

 * Note: calling this function when the same control is used in pending requests

 * is untested. It should work (a request with the wrong size of the control

 * will drop that control silently), but it will be very confusing.

 */

int __v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,

				  u32 dims[V4L2_CTRL_MAX_DIMS]);



/**

 * v4l2_ctrl_modify_dimensions() - Update the dimensions of an array control.

 *

 * @ctrl:	The control to update.

 * @dims:	The control's new dimensions.

 *

 * Update the dimensions of an array control on the fly. The elements of the

 * array are reset to their default value, even if the dimensions are

 * unchanged.

 *

 * An error is returned if @dims is invalid for this control type.

 *

 * This function assumes that the control handler is not locked and will

 * take the lock itself.

 *

 * Note: calling this function when the same control is used in pending requests

 * is untested. It should work (a request with the wrong size of the control

 * will drop that control silently), but it will be very confusing.

 */

static inline int v4l2_ctrl_modify_dimensions(struct v4l2_ctrl *ctrl,

					      u32 dims[V4L2_CTRL_MAX_DIMS])

{

	int rval;



	v4l2_ctrl_lock(ctrl);

	rval = __v4l2_ctrl_modify_dimensions(ctrl, dims);

	v4l2_ctrl_unlock(ctrl);



	return rval;

}



/**

 * v4l2_ctrl_notify() - Function to set a notify callback for a control.

 *