[PATCH v2] media/v4l2-ctrls: Always run s_ctrl on volatile ctrls

From: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
To: Hans Verkuil <hverkuil@xs4all.nl>,
	Hans Verkuil <hans.verkuil@cisco.com>,
	Mauro Carvalho Chehab <mchehab@osg.samsung.com>,
	Sylwester Nawrocki <s.nawrocki@samsung.com>,
	Antti Palosaari <crope@iki.fi>,
	Sakari Ailus <sakari.ailus@linux.intel.com>,
	linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Subject: [PATCH v2] media/v4l2-ctrls: Always run s_ctrl on volatile ctrls
Date: Tue, 17 Feb 2015 13:21:21 +0100	[thread overview]
Message-ID: <1424175681-19787-1-git-send-email-ricardo.ribalda@gmail.com> (raw)

Volatile controls can change their value outside the v4l-ctrl framework.
We should ignore the cached written value of the ctrl when evaluating if
we should run s_ctrl.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
---

v2: Do volatile test, once you know ctrl is not NULL

 drivers/media/v4l2-core/v4l2-ctrls.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 45c5b47..f0f58dd 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -1605,10 +1605,13 @@ static int cluster_changed(struct v4l2_ctrl *master)
 
 	for (i = 0; i < master->ncontrols; i++) {
 		struct v4l2_ctrl *ctrl = master->cluster[i];
-		bool ctrl_changed = false;
+		bool ctrl_changed;
 
 		if (ctrl == NULL)
 			continue;
+
+		ctrl_changed = ctrl->flags & V4L2_CTRL_FLAG_VOLATILE;
+
 		for (idx = 0; !ctrl_changed && idx < ctrl->elems; idx++)
 			ctrl_changed = !ctrl->type_ops->equal(ctrl, idx,
 				ctrl->p_cur, ctrl->p_new);
-- 
2.1.4

