# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2 --- $id: http://devicetree.org/schemas/auxdisplay/hit,hd44780.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: Hitachi HD44780 Character LCD Controller maintainers: - Geert Uytterhoeven description: The Hitachi HD44780 Character LCD Controller is commonly used on character LCDs that can display one or more lines of text. It exposes an M6800 bus interface, which can be used in either 4-bit or 8-bit mode. properties: compatible: const: hit,hd44780 data-gpios: description: GPIO pins connected to the data signal lines DB0-DB7 (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface. oneOf: - maxItems: 4 - maxItems: 8 enable-gpios: description: GPIO pin connected to the "E" (Enable) signal line of the LCD Controller's bus interface. maxItems: 1 rs-gpios: description: GPIO pin connected to the "RS" (Register Select) signal line of the LCD Controller's bus interface. maxItems: 1 rw-gpios: description: GPIO pin connected to the "RW" (Read/Write) signal line of the LCD Controller's bus interface. maxItems: 1 backlight-gpios: description: GPIO pin used for enabling the LCD's backlight. maxItems: 1 display-height-chars: description: Height of the display, in character cells, $ref: /schemas/types.yaml#/definitions/uint32 minimum: 1 maximum: 4 display-width-chars: description: Width of the display, in character cells. $ref: /schemas/types.yaml#/definitions/uint32 minimum: 1 maximum: 64 internal-buffer-width: description: Internal buffer width (default is 40 for displays with 1 or 2 lines, and display-width-chars for displays with more than 2 lines). $ref: /schemas/types.yaml#/definitions/uint32 minimum: 1 maximum: 64 required: - compatible - data-gpios - enable-gpios - rs-gpios - display-height-chars - display-width-chars additionalProperties: false examples: - | #include auxdisplay { compatible = "hit,hd44780"; data-gpios = <&hc595 0 GPIO_ACTIVE_HIGH>, <&hc595 1 GPIO_ACTIVE_HIGH>, <&hc595 2 GPIO_ACTIVE_HIGH>, <&hc595 3 GPIO_ACTIVE_HIGH>; enable-gpios = <&hc595 4 GPIO_ACTIVE_HIGH>; rs-gpios = <&hc595 5 GPIO_ACTIVE_HIGH>; display-height-chars = <2>; display-width-chars = <16>; };