V4L/DVB (5089): Pvrusb2: V4L EXT_CTRLS fixup

Attempts to enumerate or operate on a group of EXT_CTRLS where the
group size is zero is OK; don't fail on such operations.  At least one
application uses this to probe for the existence of this API so let it
succeed.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-v4l2.c b/drivers/media/video/pvrusb2/pvrusb2-v4l2.c
index 5b1260c5ff5b..91c422599877 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-v4l2.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-v4l2.c
@@ -636,6 +636,7 @@ static int pvr2_v4l2_do_ioctl(struct inode *inode, struct file *file,
                 struct v4l2_ext_control *ctrl;
                 unsigned int idx;
                 int val;
+                ret = 0;
                 for (idx = 0; idx < ctls->count; idx++) {
                         ctrl = ctls->controls + idx;
                         ret = pvr2_ctrl_get_value(
@@ -658,6 +659,7 @@ static int pvr2_v4l2_do_ioctl(struct inode *inode, struct file *file,
                         (struct v4l2_ext_controls *)arg;
                 struct v4l2_ext_control *ctrl;
                 unsigned int idx;
+                ret = 0;
                 for (idx = 0; idx < ctls->count; idx++) {
                         ctrl = ctls->controls + idx;
                         ret = pvr2_ctrl_set_value(
@@ -680,6 +682,7 @@ static int pvr2_v4l2_do_ioctl(struct inode *inode, struct file *file,
                 unsigned int idx;
                 /* For the moment just validate that the requested control
                    actually exists. */
+                ret = 0;
                 for (idx = 0; idx < ctls->count; idx++) {
                         ctrl = ctls->controls + idx;
                         pctl = pvr2_hdw_get_ctrl_v4l(hdw,ctrl->id);