Commit 7a9b109d authored by Sakari Ailus's avatar Sakari Ailus Committed by Mauro Carvalho Chehab
Browse files

media: v4l: ctrl: Provide unlocked variant of v4l2_ctrl_grab 



Sometimes it may be necessary to grab a control while holding the control
handler's lock. Provide an unlocked variant of v4l2_ctrl_grab for the
purpose --- it's called __v4l2_ctrl_grab.

Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: default avatarHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent 9a8aaa28

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

+4 −4
Original line number Diff line number Diff line
@@ -2511,14 +2511,15 @@ void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active) 
}

EXPORT_SYMBOL(v4l2_ctrl_activate);



void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)

void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)

{

	bool old;



	if (ctrl == NULL)

		return;



	v4l2_ctrl_lock(ctrl);

	lockdep_assert_held(ctrl->handler->lock);



	if (grabbed)

		/* set V4L2_CTRL_FLAG_GRABBED */

		old = test_and_set_bit(1, &ctrl->flags);
@@ -2527,9 +2528,8 @@ void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed) 
		old = test_and_clear_bit(1, &ctrl->flags);

	if (old != grabbed)

		send_event(NULL, ctrl, V4L2_EVENT_CTRL_CH_FLAGS);

	v4l2_ctrl_unlock(ctrl);

}

EXPORT_SYMBOL(v4l2_ctrl_grab);

EXPORT_SYMBOL(__v4l2_ctrl_grab);



/* Log the control name and value */

static void log_ctrl(const struct v4l2_ctrl *ctrl,

include/media/v4l2-ctrls.h

+25 −1
Original line number Diff line number Diff line
@@ -728,6 +728,22 @@ struct v4l2_ctrl *v4l2_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id); 
 */

void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active);



/**

 * __v4l2_ctrl_grab() - Unlocked variant of v4l2_ctrl_grab.

 *

 * @ctrl:	The control to (de)activate.

 * @grabbed:	True if the control should become grabbed.

 *

 * This sets or clears the V4L2_CTRL_FLAG_GRABBED flag atomically.

 * Does nothing if @ctrl == NULL.

 * The V4L2_EVENT_CTRL event will be generated afterwards.

 * This will usually be called when starting or stopping streaming in the

 * driver.

 *

 * This function assumes that the control handler is locked by the caller.

 */

void __v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);



/**

 * v4l2_ctrl_grab() - Mark the control as grabbed or not grabbed.

 *
@@ -743,7 +759,15 @@ void v4l2_ctrl_activate(struct v4l2_ctrl *ctrl, bool active); 
 * This function assumes that the control handler is not locked and will

 * take the lock itself.

 */

void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed);

static inline void v4l2_ctrl_grab(struct v4l2_ctrl *ctrl, bool grabbed)

{

	if (!ctrl)

		return;



	v4l2_ctrl_lock(ctrl);

	__v4l2_ctrl_grab(ctrl, grabbed);

	v4l2_ctrl_unlock(ctrl);

}



/**

 *__v4l2_ctrl_modify_range() - Unlocked variant of v4l2_ctrl_modify_range()

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