openwrt/target/linux/bcm27xx/patches-5.15/950-0792-dt-bindings-display-add-bindings-for-MIPI-DBI-compat.patch
Álvaro Fernández Rojas 20ea6adbf1 bcm27xx: add support for linux v5.15
Build system: x86_64
Build-tested: bcm2708, bcm2709, bcm2710, bcm2711
Run-tested: bcm2708/RPiB+, bcm2709/RPi3B, bcm2710/RPi3B, bcm2711/RPi4B

Signed-off-by: Marty Jones <mj8263788@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2022-05-17 15:11:22 +02:00

177 lines
5.3 KiB
Diff

From e39c2eeca4868a7cf34e34fb9a9ca7119c30372a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= <noralf@tronnes.org>
Date: Sun, 27 Feb 2022 13:47:09 +0100
Subject: [PATCH] dt-bindings: display: add bindings for MIPI DBI
compatible SPI panels
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
commit 2f3468b upstream.
Add binding for MIPI DBI compatible SPI panels.
v6:
- Fix indentation (Rob)
v5:
- Add sainsmart18 to compatible items (Rob)
- Expand write-only description (Sam)
v4:
- There should only be two compatible (Maxime)
- s/panel-dbi-spi/panel-mipi-dbi-spi/in compatible
v3:
- Move properties to Device Tree (Maxime)
- Use contains for compatible (Maxime)
- Add backlight property to example
- Flesh out description
v2:
- Fix path for panel-common.yaml
- Use unevaluatedProperties
- Drop properties which are in the allOf section
- Drop model property (Rob)
Acked-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220227124713.39766-2-noralf@tronnes.org
---
.../display/panel/panel-mipi-dbi-spi.yaml | 126 ++++++++++++++++++
1 file changed, 126 insertions(+)
create mode 100644 Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml
@@ -0,0 +1,126 @@
+# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/panel-mipi-dbi-spi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MIPI DBI SPI Panel
+
+maintainers:
+ - Noralf Trønnes <noralf@tronnes.org>
+
+description: |
+ This binding is for display panels using a MIPI DBI compatible controller
+ in SPI mode.
+
+ The MIPI Alliance Standard for Display Bus Interface defines the electrical
+ and logical interfaces for display controllers historically used in mobile
+ phones. The standard defines 4 display architecture types and this binding is
+ for type 1 which has full frame memory. There are 3 interface types in the
+ standard and type C is the serial interface.
+
+ The standard defines the following interface signals for type C:
+ - Power:
+ - Vdd: Power supply for display module
+ - Vddi: Logic level supply for interface signals
+ Combined into one in this binding called: power-supply
+ - Interface:
+ - CSx: Chip select
+ - SCL: Serial clock
+ - Dout: Serial out
+ - Din: Serial in
+ - SDA: Bidrectional in/out
+ - D/CX: Data/command selection, high=data, low=command
+ Called dc-gpios in this binding.
+ - RESX: Reset when low
+ Called reset-gpios in this binding.
+
+ The type C interface has 3 options:
+
+ - Option 1: 9-bit mode and D/CX as the 9th bit
+ | Command | the next command or following data |
+ |<0><D7><D6><D5><D4><D3><D2><D1><D0>|<D/CX><D7><D6><D5><D4><D3><D2><D1><D0>|
+
+ - Option 2: 16-bit mode and D/CX as a 9th bit
+ | Command or data |
+ |<X><X><X><X><X><X><X><D/CX><D7><D6><D5><D4><D3><D2><D1><D0>|
+
+ - Option 3: 8-bit mode and D/CX as a separate interface line
+ | Command or data |
+ |<D7><D6><D5><D4><D3><D2><D1><D0>|
+
+ The panel resolution is specified using the panel-timing node properties
+ hactive (width) and vactive (height). The other mandatory panel-timing
+ properties should be set to zero except clock-frequency which can be
+ optionally set to inform about the actual pixel clock frequency.
+
+ If the panel is wired to the controller at an offset specify this using
+ hback-porch (x-offset) and vback-porch (y-offset).
+
+allOf:
+ - $ref: panel-common.yaml#
+ - $ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+ compatible:
+ items:
+ - enum:
+ - sainsmart18
+ - const: panel-mipi-dbi-spi
+
+ write-only:
+ type: boolean
+ description:
+ Controller is not readable (ie. Din (MISO on the SPI interface) is not
+ wired up).
+
+ dc-gpios:
+ maxItems: 1
+ description: |
+ Controller data/command selection (D/CX) in 4-line SPI mode.
+ If not set, the controller is in 3-line SPI mode.
+
+required:
+ - compatible
+ - reg
+ - panel-timing
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ display@0{
+ compatible = "sainsmart18", "panel-mipi-dbi-spi";
+ reg = <0>;
+ spi-max-frequency = <40000000>;
+
+ dc-gpios = <&gpio 24 GPIO_ACTIVE_HIGH>;
+ reset-gpios = <&gpio 25 GPIO_ACTIVE_HIGH>;
+ write-only;
+
+ backlight = <&backlight>;
+
+ width-mm = <35>;
+ height-mm = <28>;
+
+ panel-timing {
+ hactive = <160>;
+ vactive = <128>;
+ hback-porch = <0>;
+ vback-porch = <0>;
+ clock-frequency = <0>;
+ hfront-porch = <0>;
+ hsync-len = <0>;
+ vfront-porch = <0>;
+ vsync-len = <0>;
+ };
+ };
+ };
+
+...