[media] v4l2-ctrls: introduce call_op define

Add the call_op define to safely call the control ops. This also allows
for controls without any ops such as the 'control class' controls.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil 2011-05-25 06:04:58 -03:00 committed by Mauro Carvalho Chehab
parent c20eb18ce1
commit 54c911eb91

View file

@ -25,6 +25,9 @@
#include <media/v4l2-ctrls.h>
#include <media/v4l2-dev.h>
#define call_op(master, op) \
((master->ops && master->ops->op) ? master->ops->op(master) : 0)
/* Internal temporary helper struct, one for each v4l2_ext_control */
struct ctrl_helper {
/* The control corresponding to the v4l2_ext_control ID field. */
@ -1291,7 +1294,7 @@ int v4l2_ctrl_handler_setup(struct v4l2_ctrl_handler *hdl)
if (ctrl->type == V4L2_CTRL_TYPE_BUTTON ||
(ctrl->flags & V4L2_CTRL_FLAG_READ_ONLY))
continue;
ret = master->ops->s_ctrl(master);
ret = call_op(master, s_ctrl);
if (ret)
break;
for (i = 0; i < master->ncontrols; i++)
@ -1568,8 +1571,8 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl, struct v4l2_ext_controls *cs
v4l2_ctrl_lock(master);
/* g_volatile_ctrl will update the current control values */
if (ctrl->is_volatile && master->ops->g_volatile_ctrl)
ret = master->ops->g_volatile_ctrl(master);
if (ctrl->is_volatile)
ret = call_op(master, g_volatile_ctrl);
/* If OK, then copy the current control values to the caller */
if (!ret)
ret = cluster_walk(i, cs, helpers, cur_to_user);
@ -1600,8 +1603,8 @@ static int get_ctrl(struct v4l2_ctrl *ctrl, s32 *val)
v4l2_ctrl_lock(master);
/* g_volatile_ctrl will update the current control values */
if (ctrl->is_volatile && master->ops->g_volatile_ctrl)
ret = master->ops->g_volatile_ctrl(master);
if (ctrl->is_volatile)
ret = call_op(master, g_volatile_ctrl);
*val = ctrl->cur.val;
v4l2_ctrl_unlock(master);
return ret;
@ -1675,12 +1678,12 @@ static int try_or_set_control_cluster(struct v4l2_ctrl *master, bool set)
/* For larger clusters you have to call try_ctrl again to
verify that the controls are still valid after the
'cur_to_new' above. */
if (!ret && master->ops->try_ctrl && try)
ret = master->ops->try_ctrl(master);
if (!ret && try)
ret = call_op(master, try_ctrl);
/* Don't set if there is no change */
if (!ret && set && cluster_changed(master)) {
ret = master->ops->s_ctrl(master);
ret = call_op(master, s_ctrl);
/* If OK, then make the new values permanent. */
if (!ret)
for (i = 0; i < master->ncontrols; i++)