V4L2: Set standard prior to tuner frequency.

Some V4L2 devices (e.g. Hauppauge EXETER boards) compute the tuner
frequency depending on the configured standard, so the standard needs to
be set first.
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/access/v4l2.c

@@ -1851,6 +1851,32 @@ static int OpenVideoDev( vlc_object_t *p_obj, demux_sys_t *p_sys, bool b_demux )
     }
 #endif
 
+    /* Select standard */
+
+    if( p_sys->i_selected_standard_id != V4L2_STD_UNKNOWN )
+    {
+        if( v4l2_ioctl( i_fd, VIDIOC_S_STD, &p_sys->i_selected_standard_id ) < 0 )
+        {
+            msg_Err( p_obj, "cannot set standard (%m)" );
+            goto open_failed;
+        }
+        if( v4l2_ioctl( i_fd, VIDIOC_G_STD, &p_sys->i_selected_standard_id ) < 0 )
+        {
+            msg_Err( p_obj, "cannot get standard (%m). This should never happen!" );
+            goto open_failed;
+        }
+        msg_Dbg( p_obj, "Set standard to (0x%"PRIx64"):", p_sys->i_selected_standard_id );
+        int i_standard;
+        for( i_standard = 0; i_standard<p_sys->i_standard; i_standard++)
+        {
+            if( p_sys->p_standards[i_standard].id & p_sys->i_selected_standard_id )
+            {
+                msg_Dbg( p_obj, "  %s",
+                        p_sys->p_standards[i_standard].name );
+            }
+        }
+    }
+
     /* Tune the tuner */
     if( p_sys->i_frequency >= 0 )
     {
@@ -1892,32 +1918,6 @@ static int OpenVideoDev( vlc_object_t *p_obj, demux_sys_t *p_sys, bool b_demux )
         msg_Dbg( p_obj, "Tuner audio mode set" );
     }
 
-    /* Select standard */
-
-    if( p_sys->i_selected_standard_id != V4L2_STD_UNKNOWN )
-    {
-        if( v4l2_ioctl( i_fd, VIDIOC_S_STD, &p_sys->i_selected_standard_id ) < 0 )
-        {
-            msg_Err( p_obj, "cannot set standard (%m)" );
-            goto open_failed;
-        }
-        if( v4l2_ioctl( i_fd, VIDIOC_G_STD, &p_sys->i_selected_standard_id ) < 0 )
-        {
-            msg_Err( p_obj, "cannot get standard (%m). This should never happen!" );
-            goto open_failed;
-        }
-        msg_Dbg( p_obj, "Set standard to (0x%"PRIx64"):", p_sys->i_selected_standard_id );
-        int i_standard;
-        for( i_standard = 0; i_standard<p_sys->i_standard; i_standard++)
-        {
-            if( p_sys->p_standards[i_standard].id & p_sys->i_selected_standard_id )
-            {
-                msg_Dbg( p_obj, "  %s",
-                        p_sys->p_standards[i_standard].name );
-            }
-        }
-    }
-
     /* Select input */
 
     if( p_sys->i_selected_input >= p_sys->i_input )