V4L/DVB (8498): uvcvideo: Return sensible min and max values when querying a boolean control.

Although the V4L2 spec states that the minimum and maximum fields may not be
valid for control types other than V4L2_CTRL_TYPE_INTEGER, it makes sense
to set the bounds to 0 and 1 for boolean controls instead of returning
uninitialized values.

Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c
index f54d06a8af92..626f4ad7e876 100644
--- a/drivers/media/video/uvc/uvc_ctrl.c
+++ b/drivers/media/video/uvc/uvc_ctrl.c
@@ -592,6 +592,7 @@ int uvc_query_v4l2_ctrl(struct uvc_video_device *video,
         if (ctrl == NULL)
                 return -EINVAL;
 
+        memset(v4l2_ctrl, 0, sizeof *v4l2_ctrl);
         v4l2_ctrl->id = mapping->id;
         v4l2_ctrl->type = mapping->v4l2_type;
         strncpy(v4l2_ctrl->name, mapping->name, sizeof v4l2_ctrl->name);
@@ -608,7 +609,8 @@ int uvc_query_v4l2_ctrl(struct uvc_video_device *video,
                 v4l2_ctrl->default_value = uvc_get_le_value(data, mapping);
         }
 
-        if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
+        switch (mapping->v4l2_type) {
+        case V4L2_CTRL_TYPE_MENU:
                 v4l2_ctrl->minimum = 0;
                 v4l2_ctrl->maximum = mapping->menu_count - 1;
                 v4l2_ctrl->step = 1;
@@ -622,6 +624,15 @@ int uvc_query_v4l2_ctrl(struct uvc_video_device *video,
                 }
 
                 return 0;
+
+        case V4L2_CTRL_TYPE_BOOLEAN:
+                v4l2_ctrl->minimum = 0;
+                v4l2_ctrl->maximum = 1;
+                v4l2_ctrl->step = 1;
+                return 0;
+
+        default:
+                break;
         }
 
         if (ctrl->info->flags & UVC_CONTROL_GET_MIN) {