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1DT bindings for the Hitachi HD44780 Character LCD Controller
2
3The Hitachi HD44780 Character LCD Controller is commonly used on character LCDs
4that can display one or more lines of text. It exposes an M6800 bus interface,
5which can be used in either 4-bit or 8-bit mode.
6
7Required properties:
8  - compatible: Must contain "hit,hd44780",
9  - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
10    referring to the GPIO pins connected to the data signal lines DB0-DB7
11    (8-bit mode) or DB4-DB7 (4-bit mode) of the LCD Controller's bus interface,
12  - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
13    connected to the "E" (Enable) signal line of the LCD Controller's bus
14    interface,
15  - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
16    connected to the "RS" (Register Select) signal line of the LCD Controller's
17    bus interface,
18  - display-height-chars: Height of the display, in character cells,
19  - display-width-chars: Width of the display, in character cells.
20
21Optional properties:
22  - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
23    connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
24    interface,
25  - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
26    used for enabling the LCD's backlight,
27  - internal-buffer-width: Internal buffer width (default is 40 for displays
28    with 1 or 2 lines, and display-width-chars for displays with more than 2
29    lines).
30
31Example:
32
33	auxdisplay {
34		compatible = "hit,hd44780";
35
36		data-gpios = <&hc595 0 GPIO_ACTIVE_HIGH>,
37			     <&hc595 1 GPIO_ACTIVE_HIGH>,
38			     <&hc595 2 GPIO_ACTIVE_HIGH>,
39			     <&hc595 3 GPIO_ACTIVE_HIGH>;
40		enable-gpios = <&hc595 4 GPIO_ACTIVE_HIGH>;
41		rs-gpios = <&hc595 5 GPIO_ACTIVE_HIGH>;
42
43		display-height-chars = <2>;
44		display-width-chars = <16>;
45	};
46