[PATCHv2 4/8] dt-bindings: panel: common: document orientation property

[Sebastian Reichel]

Introduce new "orientation" property for describing in which
orientation a panel has been mounted to the device. This can
be used by the operating system to automatically rotate the
display correctly.

Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxxxx>
---
 .../devicetree/bindings/display/panel/panel-common.txt     | 12 ++++++++++++
 include/dt-bindings/display/common.h                       | 14 ++++++++++++++
 2 files changed, 26 insertions(+)
 create mode 100644 include/dt-bindings/display/common.h

diff --git a/Documentation/devicetree/bindings/display/panel/panel-common.txt b/Documentation/devicetree/bindings/display/panel/panel-common.txt
index 557fa765adcb..c646b8908458 100644
--- a/Documentation/devicetree/bindings/display/panel/panel-common.txt
+++ b/Documentation/devicetree/bindings/display/panel/panel-common.txt
@@ -18,6 +18,18 @@ Descriptive Properties
   physical area where images are displayed. These properties are expressed in
   millimeters and rounded to the closest unit.
 
+- orientation: The orientation property specifies the panel orientation
+  in relation to the device's casing. The following values are possible:
+
+   * 0 = The top side of the panel matches the top side of the device's
+         casing.
+   * 1 = The top side of the panel matches the bottom side of the device's
+         casing. In other words the panel is mounted upside-down.
+   * 2 = The left side of the panel matches the top side of the device's
+         casing.
+   * 3 = The right side of the panel matches the top side of the device's
+         casing.
+
 - label: The label property specifies a symbolic name for the panel as a
   string suitable for use by humans. It typically contains a name inscribed on
   the system (e.g. as an affixed label) or specified in the system's
diff --git a/include/dt-bindings/display/common.h b/include/dt-bindings/display/common.h
new file mode 100644
index 000000000000..a864775445a0
--- /dev/null
+++ b/include/dt-bindings/display/common.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides common constants for displays
+ */
+
+#ifndef _DT_BINDINGS_DISPLAY_COMMON_H
+#define _DT_BINDINGS_DISPLAY_COMMON_H
+
+#define PANEL_ORIENTATION_NORMAL 0
+#define PANEL_ORIENTATION_BOTTOM_UP 1
+#define PANEL_ORIENTATION_LEFT_UP 2
+#define PANEL_ORIENTATION_RIGHT_UP 3
+
+#endif
-- 
2.15.1