cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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hit,hd44780.yaml (3630B)

      1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
      2%YAML 1.2
      3---
      4$id: http://devicetree.org/schemas/auxdisplay/hit,hd44780.yaml#
      5$schema: http://devicetree.org/meta-schemas/core.yaml#
      6
      7title: Hitachi HD44780 Character LCD Controller
      8
      9maintainers:
     10  - Geert Uytterhoeven <geert@linux-m68k.org>
     11
     12description:
     13  The Hitachi HD44780 Character LCD Controller is commonly used on character
     14  LCDs that can display one or more lines of text. It exposes an M6800 bus
     15  interface, which can be used in either 4-bit or 8-bit mode. By using a
     16  GPIO expander it is possible to use the driver with one of the popular I2C
     17  expander boards based on the PCF8574 available for these displays. For
     18  an example see below.
     19
     20properties:
     21  compatible:
     22    const: hit,hd44780
     23
     24  data-gpios:
     25    description:
     26      GPIO pins connected to the data signal lines DB0-DB7 (8-bit mode) or
     27      DB4-DB7 (4-bit mode) of the LCD Controller's bus interface.
     28    oneOf:
     29      - maxItems: 4
     30      - maxItems: 8
     31
     32  enable-gpios:
     33    description:
     34      GPIO pin connected to the "E" (Enable) signal line of the LCD
     35      Controller's bus interface.
     36    maxItems: 1
     37
     38  rs-gpios:
     39    description:
     40      GPIO pin connected to the "RS" (Register Select) signal line of the LCD
     41      Controller's bus interface.
     42    maxItems: 1
     43
     44  rw-gpios:
     45    description:
     46      GPIO pin connected to the "RW" (Read/Write) signal line of the LCD
     47      Controller's bus interface.
     48    maxItems: 1
     49
     50  backlight-gpios:
     51    description: GPIO pin used for enabling the LCD's backlight.
     52    maxItems: 1
     53
     54  display-height-chars:
     55    description: Height of the display, in character cells,
     56    $ref: /schemas/types.yaml#/definitions/uint32
     57    minimum: 1
     58    maximum: 4
     59
     60  display-width-chars:
     61    description: Width of the display, in character cells.
     62    $ref: /schemas/types.yaml#/definitions/uint32
     63    minimum: 1
     64    maximum: 64
     65
     66  internal-buffer-width:
     67    description:
     68      Internal buffer width (default is 40 for displays with 1 or 2 lines, and
     69      display-width-chars for displays with more than 2 lines).
     70    $ref: /schemas/types.yaml#/definitions/uint32
     71    minimum: 1
     72    maximum: 64
     73
     74required:
     75  - compatible
     76  - data-gpios
     77  - enable-gpios
     78  - rs-gpios
     79  - display-height-chars
     80  - display-width-chars
     81
     82additionalProperties: false
     83
     84examples:
     85  - |
     86    #include <dt-bindings/gpio/gpio.h>
     87    auxdisplay {
     88            compatible = "hit,hd44780";
     89
     90            data-gpios = <&hc595 0 GPIO_ACTIVE_HIGH>,
     91                         <&hc595 1 GPIO_ACTIVE_HIGH>,
     92                         <&hc595 2 GPIO_ACTIVE_HIGH>,
     93                         <&hc595 3 GPIO_ACTIVE_HIGH>;
     94            enable-gpios = <&hc595 4 GPIO_ACTIVE_HIGH>;
     95            rs-gpios = <&hc595 5 GPIO_ACTIVE_HIGH>;
     96
     97            display-height-chars = <2>;
     98            display-width-chars = <16>;
     99    };
    100  - |
    101    #include <dt-bindings/gpio/gpio.h>
    102    i2c {
    103            #address-cells = <1>;
    104            #size-cells = <0>;
    105
    106            pcf8574: pcf8574@27 {
    107                    compatible = "nxp,pcf8574";
    108                    reg = <0x27>;
    109                    gpio-controller;
    110                    #gpio-cells = <2>;
    111            };
    112    };
    113    hd44780 {
    114            compatible = "hit,hd44780";
    115            display-height-chars = <2>;
    116            display-width-chars  = <16>;
    117            data-gpios = <&pcf8574 4 0>,
    118                         <&pcf8574 5 0>,
    119                         <&pcf8574 6 0>,
    120                         <&pcf8574 7 0>;
    121            enable-gpios = <&pcf8574 2 0>;
    122            rs-gpios = <&pcf8574 0 0>;
    123            rw-gpios = <&pcf8574 1 0>;
    124            backlight-gpios = <&pcf8574 3 0>;
    125    };