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| author | Sakari Ailus <sakari.ailus@linux.intel.com> | 2018-07-19 14:11:40 +0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab+samsung@kernel.org> | 2018-10-05 16:37:45 +0300 |
| commit | 7a9b109d91cfc6089006378efd515cc287bdef67 (patch) | |
| tree | 11d0a247921826857b4c2a74449e71d115ae75a4 | |
| parent | 9a8aaa28f54c209bd36ac798d4ed9f3ea925b275 (diff) | |
| download | linux-7a9b109d91cfc6089006378efd515cc287bdef67.tar.xz | |
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: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-ctrls.c | 8 | ||||
| -rw-r--r-- | include/media/v4l2-ctrls.h | 26 |
2 files changed, 29 insertions, 5 deletions
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c index ab393adf51eb..4c0ecf29d278 100644 --- a/drivers/media/v4l2-core/v4l2-ctrls.c +++ b/drivers/media/v4l2-core/v4l2-ctrls.c @@ -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, diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h index f615ba1b29dd..ff89df428f79 100644 --- a/include/media/v4l2-ctrls.h +++ b/include/media/v4l2-ctrls.h @@ -729,6 +729,22 @@ 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. * * @ctrl: The control to (de)activate. @@ -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() |