[gnome-control-center] display: Don't show rotation for builtin display on tablets

[Bastien Nocera <hadess src gnome org>]

commit b6d7bb856d2d840b852ff3cb22cea119b670eea8
Author: Bastien Nocera <hadess hadess net>
Date:   Thu Jun 4 19:17:43 2015 +0200

    display: Don't show rotation for builtin display on tablets
    
    If there's an accelerometer builtin to the display, don't show the
    rotation buttons, it will be handled by the user rotating the display,
    eventually with the rotation lock in use.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=750410

 panels/display/cc-display-panel.c |  127 +++++++++++++++++++++++++++++++++++-
 1 files changed, 123 insertions(+), 4 deletions(-)
---
diff --git a/panels/display/cc-display-panel.c b/panels/display/cc-display-panel.c
index 9c5f1a3..6c73a74 100644
--- a/panels/display/cc-display-panel.c
+++ b/panels/display/cc-display-panel.c
@@ -87,6 +87,10 @@ struct _CcDisplayPanelPrivate
 
   GDBusProxy *shell_proxy;
   GCancellable *shell_cancellable;
+
+  guint       sensor_watch_id;
+  GDBusProxy *iio_sensor_proxy;
+  gboolean    has_accelerometer;
 };
 
 typedef struct
@@ -189,6 +193,14 @@ cc_display_panel_dispose (GObject *object)
   CcShell *shell;
   GtkWidget *toplevel;
 
+  if (priv->sensor_watch_id > 0)
+    {
+      g_bus_unwatch_name (priv->sensor_watch_id);
+      priv->sensor_watch_id = 0;
+    }
+
+  g_clear_object (&priv->iio_sensor_proxy);
+
   if (output_ids)
     {
       g_hash_table_destroy (output_ids);
@@ -1987,6 +1999,30 @@ sanity_check_rotation (GnomeRROutputInfo *output)
   gnome_rr_output_info_set_rotation (output, rotation);
 }
 
+static gboolean
+should_show_rotation (CcDisplayPanel *panel,
+                      GnomeRROutput  *output)
+{
+  CcDisplayPanelPrivate *priv = panel->priv;
+  gboolean supports_rotation;
+
+  supports_rotation = gnome_rr_output_info_supports_rotation (priv->current_output,
+                                                              GNOME_RR_ROTATION_90 |
+                                                              GNOME_RR_ROTATION_180 |
+                                                              GNOME_RR_ROTATION_270);
+
+  /* Doesn't support rotation at all */
+  if (!supports_rotation)
+    return FALSE;
+
+  /* We can always rotate displays that aren't builtin */
+  if (!gnome_rr_output_is_builtin_display (output))
+    return TRUE;
+
+  /* Only offer rotation if there's no accelerometer */
+  return !priv->has_accelerometer;
+}
+
 static void
 show_setup_dialog (CcDisplayPanel *panel)
 {
@@ -2051,10 +2087,7 @@ show_setup_dialog (CcDisplayPanel *panel)
   gtk_grid_attach (GTK_GRID (priv->config_grid), preview, 0, 0, 2, 1);
 
   /* rotation */
-  show_rotation = gnome_rr_output_info_supports_rotation (priv->current_output,
-                                                          GNOME_RR_ROTATION_90 |
-                                                          GNOME_RR_ROTATION_180 |
-                                                          GNOME_RR_ROTATION_270);
+  show_rotation = should_show_rotation (panel, output);
   rotation = gnome_rr_output_info_get_rotation (priv->current_output);
 
   if (show_rotation)
@@ -2425,6 +2458,84 @@ shell_proxy_ready (GObject        *source,
 }
 
 static void
+update_has_accel (CcDisplayPanel *self)
+{
+  GVariant *v;
+
+  if (self->priv->iio_sensor_proxy == NULL)
+    {
+      g_debug ("Has no accelerometer");
+      self->priv->has_accelerometer = FALSE;
+      return;
+    }
+
+  v = g_dbus_proxy_get_cached_property (self->priv->iio_sensor_proxy, "HasAccelerometer");
+  if (v)
+    {
+      self->priv->has_accelerometer = g_variant_get_boolean (v);
+      g_variant_unref (v);
+    }
+  else
+    {
+      self->priv->has_accelerometer = FALSE;
+    }
+
+  g_debug ("Has %saccelerometer", self->priv->has_accelerometer ? "" : "no ");
+}
+
+static void
+sensor_proxy_properties_changed_cb (GDBusProxy     *proxy,
+                                    GVariant       *changed_properties,
+                                    GStrv           invalidated_properties,
+                                    CcDisplayPanel *self)
+{
+  GVariantDict dict;
+
+  g_variant_dict_init (&dict, changed_properties);
+
+  if (g_variant_dict_contains (&dict, "HasAccelerometer"))
+    update_has_accel (self);
+}
+
+static void
+sensor_proxy_appeared_cb (GDBusConnection *connection,
+                          const gchar     *name,
+                          const gchar     *name_owner,
+                          gpointer         user_data)
+{
+  CcDisplayPanel *self = user_data;
+
+  g_debug ("SensorProxy appeared");
+
+  self->priv->iio_sensor_proxy = g_dbus_proxy_new_sync (connection,
+                                                        G_DBUS_PROXY_FLAGS_NONE,
+                                                        NULL,
+                                                        "net.hadess.SensorProxy",
+                                                        "/net/hadess/SensorProxy",
+                                                        "net.hadess.SensorProxy",
+                                                        NULL,
+                                                        NULL);
+  g_return_if_fail (self->priv->iio_sensor_proxy);
+
+  g_signal_connect (self->priv->iio_sensor_proxy, "g-properties-changed",
+                    G_CALLBACK (sensor_proxy_properties_changed_cb), self);
+  update_has_accel (self);
+}
+
+static void
+sensor_proxy_vanished_cb (GDBusConnection *connection,
+                          const gchar     *name,
+                          gpointer         user_data)
+{
+  CcDisplayPanel *self = user_data;
+
+  g_debug ("SensorProxy vanished");
+
+  g_clear_object (&self->priv->iio_sensor_proxy);
+  update_has_accel (self);
+}
+
+static void
 cc_display_panel_init (CcDisplayPanel *self)
 {
   CcDisplayPanelPrivate *priv;
@@ -2521,4 +2632,12 @@ cc_display_panel_init (CcDisplayPanel *self)
                             self->priv->shell_cancellable,
                             (GAsyncReadyCallback) shell_proxy_ready,
                             self);
+
+  priv->sensor_watch_id = g_bus_watch_name (G_BUS_TYPE_SYSTEM,
+                                            "net.hadess.SensorProxy",
+                                            G_BUS_NAME_WATCHER_FLAGS_NONE,
+                                            sensor_proxy_appeared_cb,
+                                            sensor_proxy_vanished_cb,
+                                            self,
+                                            NULL);
 }