Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / Documentation / devicetree / bindings / video / display-timing.txt

diff --git a/kernel/Documentation/devicetree/bindings/video/display-timing.txt b/kernel/Documentation/devicetree/bindings/video/display-timing.txt
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+display-timing bindings
+=======================
+
+display-timings node
+--------------------
+
+required properties:
+ - none
+
+optional properties:
+ - native-mode: The native mode for the display, in case multiple modes are
+               provided. When omitted, assume the first node is the native.
+
+timing subnode
+--------------
+
+required properties:
+ - hactive, vactive: display resolution
+ - hfront-porch, hback-porch, hsync-len: horizontal display timing parameters
+   in pixels
+   vfront-porch, vback-porch, vsync-len: vertical display timing parameters in
+   lines
+ - clock-frequency: display clock in Hz
+
+optional properties:
+ - hsync-active: hsync pulse is active low/high/ignored
+ - vsync-active: vsync pulse is active low/high/ignored
+ - de-active: data-enable pulse is active low/high/ignored
+ - pixelclk-active: with
+                       - active high = drive pixel data on rising edge/
+                                       sample data on falling edge
+                       - active low  = drive pixel data on falling edge/
+                                       sample data on rising edge
+                       - ignored     = ignored
+ - interlaced (bool): boolean to enable interlaced mode
+ - doublescan (bool): boolean to enable doublescan mode
+ - doubleclk (bool): boolean to enable doubleclock mode
+
+All the optional properties that are not bool follow the following logic:
+    <1>: high active
+    <0>: low active
+    omitted: not used on hardware
+
+There are different ways of describing the capabilities of a display. The
+devicetree representation corresponds to the one commonly found in datasheets
+for displays. If a display supports multiple signal timings, the native-mode
+can be specified.
+
+The parameters are defined as:
+
+  +----------+-------------------------------------+----------+-------+
+  |          |        ↑                            |          |       |
+  |          |        |vback_porch                 |          |       |
+  |          |        ↓                            |          |       |
+  +----------#######################################----------+-------+
+  |          #        ↑                            #          |       |
+  |          #        |                            #          |       |
+  |  hback   #        |                            #  hfront  | hsync |
+  |   porch  #        |       hactive              #  porch   |  len  |
+  |<-------->#<-------+--------------------------->#<-------->|<----->|
+  |          #        |                            #          |       |
+  |          #        |vactive                     #          |       |
+  |          #        |                            #          |       |
+  |          #        ↓                            #          |       |
+  +----------#######################################----------+-------+
+  |          |        ↑                            |          |       |
+  |          |        |vfront_porch                |          |       |
+  |          |        ↓                            |          |       |
+  +----------+-------------------------------------+----------+-------+
+  |          |        ↑                            |          |       |
+  |          |        |vsync_len                   |          |       |
+  |          |        ↓                            |          |       |
+  +----------+-------------------------------------+----------+-------+
+
+Example:
+
+       display-timings {
+               native-mode = <&timing0>;
+               timing0: 1080p24 {
+                       /* 1920x1080p24 */
+                       clock-frequency = <52000000>;
+                       hactive = <1920>;
+                       vactive = <1080>;
+                       hfront-porch = <25>;
+                       hback-porch = <25>;
+                       hsync-len = <25>;
+                       vback-porch = <2>;
+                       vfront-porch = <2>;
+                       vsync-len = <2>;
+                       hsync-active = <1>;
+               };
+       };
+
+Every required property also supports the use of ranges, so the commonly used
+datasheet description with minimum, typical and maximum values can be used.
+
+Example:
+
+       timing1: timing {
+               /* 1920x1080p24 */
+               clock-frequency = <148500000>;
+               hactive = <1920>;
+               vactive = <1080>;
+               hsync-len = <0 44 60>;
+               hfront-porch = <80 88 95>;
+               hback-porch = <100 148 160>;
+               vfront-porch = <0 4 6>;
+               vback-porch = <0 36 50>;
+               vsync-len = <0 5 6>;
+       };