V4L/DVB: uvcvideo: Flag relative controls as write-only

The UVC relative controls (exposure time, iris, focus, zoom, pan/tilt)
are write-only (despite the UVC specification stating that the GET_CUR
request is mandatory). Mark the controls as such, and report the related
V4L2 controls V4L2_CTRL_FLAG_WRITE_ONLY.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 16 insertions, 12 deletions

diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c
index 5d6d7bda2336..2703c9524396 100644
--- a/drivers/media/video/uvc/uvc_ctrl.c
+++ b/drivers/media/video/uvc/uvc_ctrl.c
@@ -217,8 +217,7 @@ static struct uvc_control_info uvc_ctrls[] = {
                 .selector       = UVC_CT_EXPOSURE_TIME_RELATIVE_CONTROL,
                 .index          = 4,
                 .size           = 1,
-                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
-                                | UVC_CONTROL_RESTORE,
+                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_RESTORE,
         },
         {
                 .entity         = UVC_GUID_UVC_CAMERA,
@@ -233,8 +232,9 @@ static struct uvc_control_info uvc_ctrls[] = {
                 .selector       = UVC_CT_FOCUS_RELATIVE_CONTROL,
                 .index          = 6,
                 .size           = 2,
-                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
-                                | UVC_CONTROL_AUTO_UPDATE,
+                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_MIN
+                                | UVC_CONTROL_GET_MAX | UVC_CONTROL_GET_RES
+                                | UVC_CONTROL_GET_DEF | UVC_CONTROL_AUTO_UPDATE,
         },
         {
                 .entity         = UVC_GUID_UVC_CAMERA,
@@ -249,8 +249,7 @@ static struct uvc_control_info uvc_ctrls[] = {
                 .selector       = UVC_CT_IRIS_RELATIVE_CONTROL,
                 .index          = 8,
                 .size           = 1,
-                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_CUR
-                                | UVC_CONTROL_AUTO_UPDATE,
+                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_AUTO_UPDATE,
         },
         {
                 .entity         = UVC_GUID_UVC_CAMERA,
@@ -265,8 +264,9 @@ static struct uvc_control_info uvc_ctrls[] = {
                 .selector       = UVC_CT_ZOOM_RELATIVE_CONTROL,
                 .index          = 10,
                 .size           = 3,
-                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
-                                | UVC_CONTROL_AUTO_UPDATE,
+                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_MIN
+                                | UVC_CONTROL_GET_MAX | UVC_CONTROL_GET_RES
+                                | UVC_CONTROL_GET_DEF | UVC_CONTROL_AUTO_UPDATE,
         },
         {
                 .entity         = UVC_GUID_UVC_CAMERA,
@@ -281,8 +281,9 @@ static struct uvc_control_info uvc_ctrls[] = {
                 .selector       = UVC_CT_PANTILT_RELATIVE_CONTROL,
                 .index          = 12,
                 .size           = 4,
-                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
-                                | UVC_CONTROL_AUTO_UPDATE,
+                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_MIN
+                                | UVC_CONTROL_GET_MAX | UVC_CONTROL_GET_RES
+                                | UVC_CONTROL_GET_DEF | UVC_CONTROL_AUTO_UPDATE,
         },
         {
                 .entity         = UVC_GUID_UVC_CAMERA,
@@ -297,8 +298,9 @@ static struct uvc_control_info uvc_ctrls[] = {
                 .selector       = UVC_CT_ROLL_RELATIVE_CONTROL,
                 .index          = 14,
                 .size           = 2,
-                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_RANGE
-                                | UVC_CONTROL_AUTO_UPDATE,
+                .flags          = UVC_CONTROL_SET_CUR | UVC_CONTROL_GET_MIN
+                                | UVC_CONTROL_GET_MAX | UVC_CONTROL_GET_RES
+                                | UVC_CONTROL_GET_DEF | UVC_CONTROL_AUTO_UPDATE,
         },
         {
                 .entity         = UVC_GUID_UVC_CAMERA,
@@ -842,6 +844,8 @@ int uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
         strlcpy(v4l2_ctrl->name, mapping->name, sizeof v4l2_ctrl->name);
         v4l2_ctrl->flags = 0;
 
+        if (!(ctrl->info->flags & UVC_CONTROL_GET_CUR))
+                v4l2_ctrl->flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
         if (!(ctrl->info->flags & UVC_CONTROL_SET_CUR))
                 v4l2_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;