Add device tree binding for the Solomon Systech SSD16xx family of e-Paper display controllers (SSD1683 [1], SSD1673 [3], SSD1680 [4], SSD1681 [5]).
The binding covers the 4-wire SPI interface with required GPIO pins for reset (active-low), busy status (active-high), and data/command selection. The spi-max-frequency is capped at 20 MHz per the SSD1683 datasheet [1] which is also the maximum supported frequency amongst the family. An optional rotation property (as defined by panel-common, in degrees counter clockwise) allows static display orientation to be configured from device tree. The data/command selection GPIO pin is also kept as optional since various SSD16XX controllers such as SSD1683 [1] support 3-wire mode too with data/command selection bit transmitted as first bit before sending the data sequence. The first supported compatible is for Gooddisplay GDEY042T81 [2] which is 4.2", 400x300 resolution black/white e-paper display using SSD1683 controller. Links: [1] : https://www.crystalfontz.com/controllers/SolomonSystech/SSD1683 [2] : https://files.seeedstudio.com/wiki/Other_Display/42-epaper/GDEY042T81.pdf [3] : https://www.crystalfontz.com/controllers/SolomonSystech/SSD1673 [4] : https://www.crystalfontz.com/controllers/SolomonSystech/SSD1680 [5] : https://www.crystalfontz.com/controllers/SolomonSystech/SSD1681 Signed-off-by: Devarsh Thakkar <[email protected]> --- Changes in v3: - Rename the file to solomon,ssd1683.yaml so that it matches an actual compatible string - Drop the redundant "binding" from the subject - Describe the compatible as oneOf/items from the start so that the next patch only adds a branch instead of rewriting these lines - Reference panel/panel-common.yaml in allOf - Add spi-3wire and document that omitting dc-gpios selects 3-wire mode - Use the common 'rotation' property from panel-common instead of a local definition that said "clockwise" - Remove rotation as it is already inherited by panel-common - Set spi-3wire as true since supported by panel --- .../bindings/display/solomon,ssd1683.yaml | 85 +++++++++++++++++++ 1 file changed, 85 insertions(+) create mode 100644 Documentation/devicetree/bindings/display/solomon,ssd1683.yaml diff --git a/Documentation/devicetree/bindings/display/solomon,ssd1683.yaml b/Documentation/devicetree/bindings/display/solomon,ssd1683.yaml new file mode 100644 index 000000000000..2e2aa195fb1e --- /dev/null +++ b/Documentation/devicetree/bindings/display/solomon,ssd1683.yaml @@ -0,0 +1,85 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/display/solomon,ssd1683.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Solomon Systech SSD16xx-based e-paper display panels + +maintainers: + - Devarsh Thakkar <[email protected]> + +description: + The SSD16xx family includes e-paper display controllers (SSD1673, + SSD1680, SSD1681, SSD1683, SSD1677) with integrated gate driver, + source driver and timing controller. Different panels use these + controllers in monochrome or 3-color (black/white/red) configurations. + The controller uses a 4-wire SPI interface and requires GPIO pins for + reset, busy status, and data/command control. A 3-wire mode is also + available where the D/C bit is transmitted along the SPI data line + before each byte. + +allOf: + - $ref: panel/panel-common.yaml# + - $ref: /schemas/spi/spi-peripheral-props.yaml# + +properties: + compatible: + oneOf: + - items: + - enum: + # Good Display 4.2" 400x300 monochrome e-paper panel + - gooddisplay,gdey042t81 + - const: solomon,ssd1683 + + reg: + maxItems: 1 + + spi-max-frequency: + maximum: 20000000 + + spi-3wire: true + + reset-gpios: + maxItems: 1 + description: + GPIO connected to the RSTB (reset) pin. Active low. + + busy-gpios: + maxItems: 1 + description: + GPIO connected to the BUSY pin. Active high when the controller + is busy updating the display. + + dc-gpios: + maxItems: 1 + description: + GPIO connected to the D/C (Data/Command) pin. Low for command, + high for data. If omitted, the controller is driven in 3-wire + (9-bit) SPI mode, where the D/C bit is sent along the data line. + +required: + - compatible + - reg + - reset-gpios + - busy-gpios + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + + spi { + #address-cells = <1>; + #size-cells = <0>; + + display@0 { + compatible = "gooddisplay,gdey042t81", "solomon,ssd1683"; + reg = <0>; + spi-max-frequency = <2000000>; + reset-gpios = <&gpio1 17 GPIO_ACTIVE_LOW>; + busy-gpios = <&gpio1 18 GPIO_ACTIVE_HIGH>; + dc-gpios = <&gpio1 19 GPIO_ACTIVE_HIGH>; + }; + }; -- 2.39.1
