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author | Geert Uytterhoeven <geert@linux-m68k.org> | 2017-03-10 17:15:20 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-03-17 09:10:49 +0300 |
commit | dd9502a9e9156dd854dd0bec0dd385b4662bab3e (patch) | |
tree | d1d0b8d3ba8de569dedca418cd7f937452883440 | |
parent | 1d3b2af213902059d9f4b35eb15b53f8062dc3b3 (diff) | |
download | linux-dd9502a9e9156dd854dd0bec0dd385b4662bab3e.tar.xz |
dt-bindings: auxdisplay: Add bindings for Hitachi HD44780
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@linux-m68k.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt b/Documentation/devicetree/bindings/auxdisplay/hit,hd44780.txt new file mode 100644 index 000000000000..ee4054da458d --- /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>; + }; |