summaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/display/panel/panel-common.yaml
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/devicetree/bindings/display/panel/panel-common.yaml')
-rw-r--r--Documentation/devicetree/bindings/display/panel/panel-common.yaml159
1 files changed, 159 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/display/panel/panel-common.yaml b/Documentation/devicetree/bindings/display/panel/panel-common.yaml
new file mode 100644
index 000000000..5b38dc89c
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/panel-common.yaml
@@ -0,0 +1,159 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/panel-common.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Common Properties for Display Panels
+
+maintainers:
+ - Thierry Reding <thierry.reding@gmail.com>
+ - Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
+
+description: |
+ 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.
+
+properties:
+ # Descriptive Properties
+ width-mm:
+ description:
+ Specifies the width of the physical area where images are displayed. This
+ property is expressed in millimeters and rounded to the closest unit.
+
+ height-mm:
+ description:
+ Specifies the height of the physical area where images are displayed. This
+ property is expressed in millimeters and rounded to the closest unit.
+
+ label:
+ description: |
+ 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.
+
+ rotation:
+ description:
+ Display rotation in degrees counter clockwise (0,90,180,270)
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [0, 90, 180, 270]
+
+ # Display Timings
+ panel-timing:
+ description:
+ Most display panels are restricted to a single resolution and
+ require specific display timings. The panel-timing subnode expresses those
+ timings.
+ $ref: panel-timing.yaml#
+
+ display-timings:
+ description:
+ Some display panels support several resolutions with different timings.
+ The display-timings bindings supports specifying several timings and
+ optionally specifying which is the native mode.
+ $ref: display-timings.yaml#
+
+ # Connectivity
+ port:
+ $ref: /schemas/graph.yaml#/properties/port
+
+ ddc-i2c-bus:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ 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.
+
+ no-hpd:
+ type: boolean
+ description:
+ This panel is supposed to communicate that it's ready via HPD
+ (hot plug detect) signal, but the signal isn't hooked up so we should
+ hardcode the max delay from the panel spec when powering up the panel.
+
+ hpd-gpios:
+ maxItems: 1
+ description:
+ If Hot Plug Detect (HPD) is connected to a GPIO in the system rather
+ than a dedicated HPD pin the pin can be specified here.
+
+ # 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:
+ maxItems: 1
+ description: |
+ 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:
+ maxItems: 1
+ description:
+ Specifier for a GPIO connected 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.
+
+ te-gpios:
+ maxItems: 1
+ description:
+ GPIO spec for the tearing effect synchronization signal.
+ The tearing effect signal is active high. Active low signals can be
+ supported by inverting the GPIO specifier polarity flag.
+
+ # Power
+ power-supply:
+ description:
+ 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:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ For panels whose backlight is controlled by an external backlight
+ controller, this property contains a phandle that references the
+ controller.
+
+dependencies:
+ width-mm: [ height-mm ]
+ height-mm: [ width-mm ]
+
+additionalProperties: true
+
+...