If the v4l2 driver supports the extended controls API, use it to list controls...

If the v4l2 driver supports the extended controls API, use it to list controls (instead of the user control API).

modules/access/v4l2.c

@@ -2715,6 +2715,10 @@ static void ControlListPrint( vlc_object_t *p_obj, int i_fd,
             var_Create( p_obj, psz_name,
                         VLC_VAR_VOID | VLC_VAR_ISCOMMAND );
             break;
+        case V4L2_CTRL_TYPE_CTRL_CLASS:
+            msg_Dbg( p_obj, "    control class" );
+            var_Create( p_obj, psz_name, VLC_VAR_VOID );
+            break;
         default:
             msg_Dbg( p_obj, "    unknown control type (FIXME)" );
             /* FIXME */
@@ -2821,39 +2825,73 @@ static int ControlList( vlc_object_t *p_obj, int i_fd,
     else
         var_AddCallback( p_obj, "controls-reset", AccessControlResetCallback, NULL );
 
-    /* List public controls */
-    for( i_cid = V4L2_CID_BASE;
-         i_cid < V4L2_CID_LASTP1;
-         i_cid ++ )
+    queryctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL;
+    if( ioctl( i_fd, VIDIOC_QUERYCTRL, &queryctrl ) >= 0 )
     {
-        queryctrl.id = i_cid;
-        if( ioctl( i_fd, VIDIOC_QUERYCTRL, &queryctrl ) >= 0 )
+        msg_Dbg( p_obj, "Extended control API supported by v4l2 driver" );
+
+        /* List extended controls */
+        queryctrl.id = V4L2_CTRL_FLAG_NEXT_CTRL;
+        while( ioctl( i_fd, VIDIOC_QUERYCTRL, &queryctrl ) >= 0 )
         {
-            if( queryctrl.flags & V4L2_CTRL_FLAG_DISABLED )
-                continue;
-            msg_Dbg( p_obj, "Available control: %s (%x)",
-                     queryctrl.name, queryctrl.id );
+            switch( V4L2_CTRL_ID2CLASS( queryctrl.id ) )
+            {
+                case V4L2_CTRL_CLASS_USER:
+                    msg_Dbg( p_obj, "Available control: %s (%x)",
+                             queryctrl.name, queryctrl.id );
+                    break;
+                case V4L2_CTRL_CLASS_MPEG:
+                    msg_Dbg( p_obj, "Available MPEG control: %s (%x)",
+                             queryctrl.name, queryctrl.id );
+                    break;
+                default:
+                    msg_Dbg( p_obj, "Available private control: %s (%x)",
+                             queryctrl.name, queryctrl.id );
+                    break;
+            }
             ControlListPrint( p_obj, i_fd, queryctrl, b_reset, b_demux );
+            queryctrl.id |= V4L2_CTRL_FLAG_NEXT_CTRL;
         }
     }
-
-    /* List private controls */
-    for( i_cid = V4L2_CID_PRIVATE_BASE;
-         ;
-         i_cid ++ )
+    else
     {
-        queryctrl.id = i_cid;
-        if( ioctl( i_fd, VIDIOC_QUERYCTRL, &queryctrl ) >= 0 )
+        msg_Dbg( p_obj, "Extended control API not supported by v4l2 driver" );
+
+        /* List public controls */
+        for( i_cid = V4L2_CID_BASE;
+             i_cid < V4L2_CID_LASTP1;
+             i_cid ++ )
         {
-            if( queryctrl.flags & V4L2_CTRL_FLAG_DISABLED )
-                continue;
-            msg_Dbg( p_obj, "Available private control: %s (%x)",
-                     queryctrl.name, queryctrl.id );
-            ControlListPrint( p_obj, i_fd, queryctrl, b_reset, b_demux );
+            queryctrl.id = i_cid;
+            if( ioctl( i_fd, VIDIOC_QUERYCTRL, &queryctrl ) >= 0 )
+            {
+                if( queryctrl.flags & V4L2_CTRL_FLAG_DISABLED )
+                    continue;
+                msg_Dbg( p_obj, "Available control: %s (%x)",
+                         queryctrl.name, queryctrl.id );
+                ControlListPrint( p_obj, i_fd, queryctrl, b_reset, b_demux );
+            }
+        }
+
+        /* List private controls */
+        for( i_cid = V4L2_CID_PRIVATE_BASE;
+             ;
+             i_cid ++ )
+        {
+            queryctrl.id = i_cid;
+            if( ioctl( i_fd, VIDIOC_QUERYCTRL, &queryctrl ) >= 0 )
+            {
+                if( queryctrl.flags & V4L2_CTRL_FLAG_DISABLED )
+                    continue;
+                msg_Dbg( p_obj, "Available private control: %s (%x)",
+                         queryctrl.name, queryctrl.id );
+                ControlListPrint( p_obj, i_fd, queryctrl, b_reset, b_demux );
+            }
+            else
+                break;
         }
-        else
-            break;
     }
+
     return VLC_SUCCESS;
 }