mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-22 20:23:57 +08:00
c7c3f096eb
DT properties specifying physical properties should contain appropriate suffices indicating the units of measurement. Hence amend the HD44780 DT bindings to add "chars" suffixes to the "display-height" and "display-width" properties, and update the driver to parse them. Fixes:dd9502a9e9("dt-bindings: auxdisplay: Add bindings for Hitachi HD44780") Fixes:d47d88361f("auxdisplay: Add HD44780 Character LCD support") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
46 lines
1.8 KiB
Plaintext
46 lines
1.8 KiB
Plaintext
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-chars: Height of the display, in character cells,
|
|
- display-width-chars: 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-chars 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-chars = <2>;
|
|
display-width-chars = <16>;
|
|
};
|