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diff --git a/Documentation/devicetree/bindings/display/panel/panel-common.txt b/Documentation/devicetree/bindings/display/panel/panel-common.txt deleted file mode 100644 index 5d2519af4bb5..000000000000 --- a/Documentation/devicetree/bindings/display/panel/panel-common.txt +++ /dev/null @@ -1,101 +0,0 @@ -Common Properties for Display Panel -=================================== - -This document defines device tree properties common to several classes of -display panels. It doesn't constitue a device tree binding specification by -itself but is meant to be referenced by device tree bindings. - -When referenced from panel device tree bindings the properties defined in this -document are defined as follows. The panel device tree bindings are -responsible for defining whether each property is required or optional. - - -Descriptive Properties ----------------------- - -- width-mm, -- height-mm: The width-mm and height-mm specify the width and height of the - physical area where images are displayed. These properties are expressed in - millimeters and rounded to the closest unit. - -- 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 - documentation (e.g. in the user's manual). - - If no such name exists, and unless the property is mandatory according to - device tree bindings, it shall rather be omitted than constructed of - non-descriptive information. For instance an LCD panel in a system that - contains a single panel shall not be labelled "LCD" if that name is not - inscribed on the system or used in a descriptive fashion in system - documentation. - - -Display Timings ---------------- - -- panel-timing: Most display panels are restricted to a single resolution and - require specific display timings. The panel-timing subnode expresses those - timings as specified in the timing subnode section of the display timing - bindings defined in - Documentation/devicetree/bindings/display/panel/display-timing.txt. - - -Connectivity ------------- - -- ports: Panels receive video data through one or multiple connections. While - the nature of those connections is specific to the panel type, the - connectivity is expressed in a standard fashion using ports as specified in - the device graph bindings defined in - Documentation/devicetree/bindings/graph.txt. - -- ddc-i2c-bus: Some panels expose EDID information through an I2C-compatible - bus such as DDC2 or E-DDC. For such panels the ddc-i2c-bus contains a - phandle to the system I2C controller connected to that bus. - - -Control I/Os ------------- - -Many display panels can be controlled through pins driven by GPIOs. The nature -and timing of those control signals are device-specific and left for panel -device tree bindings to specify. The following GPIO specifiers can however be -used for panels that implement compatible control signals. - -- enable-gpios: Specifier for a GPIO connected to the panel enable control - signal. The enable signal is active high and enables operation of the panel. - This property can also be used for panels implementing an active low power - down signal, which is a negated version of the enable signal. Active low - enable signals (or active high power down signals) can be supported by - inverting the GPIO specifier polarity flag. - - Note that the enable signal control panel operation only and must not be - confused with a backlight enable signal. - -- reset-gpios: Specifier for a GPIO coonnected to the panel reset control - signal. The reset signal is active low and resets the panel internal logic - while active. Active high reset signals can be supported by inverting the - GPIO specifier polarity flag. - -Power ------ - -- power-supply: display panels require power to be supplied. While several - panels need more than one power supply with panel-specific constraints - governing the order and timings of the power supplies, in many cases a single - power supply is sufficient, either because the panel has a single power rail, - or because all its power rails can be driven by the same supply. In that case - the power-supply property specifies the supply powering the panel as a phandle - to a regulator. - -Backlight ---------- - -Most display panels include a backlight. Some of them also include a backlight -controller exposed through a control bus such as I2C or DSI. Others expose -backlight control through GPIO, PWM or other signals connected to an external -backlight controller. - -- backlight: For panels whose backlight is controlled by an external backlight - controller, this property contains a phandle that references the controller. |