[PATCH 12/13] dt-bindings: auxdisplay: Add bindings for Hitachi HD44780

From: Geert Uytterhoeven
Date: Mon Feb 06 2017 - 09:39:26 EST


Add DT bindings for an Hitachi HD44780 Character LCD Controller where
its M6800 bus interface is connected to GPIOs.

Memory-mapped configurations are not yet supported.

Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
---
.../devicetree/bindings/auxdisplay/hit,hd44780.txt | 44 ++++++++++++++++++++++
1 file changed, 44 insertions(+)
create mode 100644 Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt

diff --git a/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
new file mode 100644
index 0000000000000000..ee4054da458d412f
--- /dev/null
+++ b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt
@@ -0,0 +1,44 @@
+DT bindings for the Hitachi HD44780 Character LCD Controller
+
+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.
+
+Required properties:
+ - compatible: Must contain "hit,hd44780",
+ - data-gpios: Must contain an array of either 4 or 8 GPIO specifiers,
+ referring to the 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,
+ - enable-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ connected to the "E" (Enable) signal line of the LCD Controller's bus
+ interface,
+ - rs-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ connected to the "RS" (Register Select) signal line of the LCD Controller's
+ bus interface,
+ - display-height: Height of the display, in character cells,
+ - display-width: Width of the display, in character cells.
+
+Optional properties:
+ - rw-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ connected to the "RW" (Read/Write) signal line of the LCD Controller's bus
+ interface,
+ - backlight-gpios: Must contain a GPIO specifier, referring to the GPIO pin
+ used for enabling the LCD's backlight,
+ - internal-buffer-width: Internal buffer width (default is 40 for displays
+ with 1 or 2 lines, and display-width for displays with more than 2 lines).
+
+Example:
+
+ 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 = <2>;
+ display-width = <16>;
+ };
--
1.9.1