target/linux/brcm2708/patches-4.19/950-0155-Add-device-tree-overlay-for-HD44780.patch

   1 From 0950d997c40aa9428b886d7e1af46730b0366513 Mon Sep 17 00:00:00 2001
   2 From: Jasper Boomer <jasperboomer@gmail.com>
   3 Date: Sun, 24 Jun 2018 12:20:27 -0400
   4 Subject: [PATCH 155/703] Add device tree overlay for HD44780
   5
   6 ---
   7  arch/arm/boot/dts/overlays/Makefile           |  1 +
   8  arch/arm/boot/dts/overlays/README             | 25 ++++++++++
   9  .../boot/dts/overlays/hd44780-lcd-overlay.dts | 46 +++++++++++++++++++
  10  3 files changed, 72 insertions(+)
  11  create mode 100644 arch/arm/boot/dts/overlays/hd44780-lcd-overlay.dts
  12
  13 --- a/arch/arm/boot/dts/overlays/Makefile
  14 +++ b/arch/arm/boot/dts/overlays/Makefile
  15 @@ -38,6 +38,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
  16         gpio-no-irq.dtbo \
  17         gpio-poweroff.dtbo \
  18         gpio-shutdown.dtbo \
  19 +       hd44780-lcd.dtbo \
  20         hifiberry-amp.dtbo \
  21         hifiberry-dac.dtbo \
  22         hifiberry-dacplus.dtbo \
  23 --- a/arch/arm/boot/dts/overlays/README
  24 +++ b/arch/arm/boot/dts/overlays/README
  25 @@ -639,6 +639,31 @@ Params: gpio_pin                GPIO pin
  26                                  external pullup.
  27
  28
  29 +Name:   hd44780-lcd
  30 +Info:   Configures an HD44780 compatible LCD display. Uses 4 gpio pins for
  31 +        data, 2 gpio pins for enable and register select and 1 optional pin
  32 +        for enabling/disabling the backlight display.
  33 +Load:   dtoverlay=hd44780-lcd,<param>=<val>
  34 +Params: pin_d4                  GPIO pin for data pin D4 (default 6)
  35 +
  36 +        pin_d5                  GPIO pin for data pin D5 (default 13)
  37 +
  38 +        pin_d6                  GPIO pin for data pin D6 (default 19)
  39 +
  40 +        pin_d7                  GPIO pin for data pin D7 (default 26)
  41 +
  42 +        pin_en                  GPIO pin for "Enable" (default 21)
  43 +
  44 +        pin_rs                  GPIO pin for "Register Select" (default 20)
  45 +
  46 +        pin_bl                  Optional pin for enabling/disabling the
  47 +                                display backlight. (default disabled)
  48 +
  49 +        display_height          Height of the display in characters
  50 +
  51 +        display_width           Width of the display in characters
  52 +
  53 +
  54  Name:   hifiberry-amp
  55  Info:   Configures the HifiBerry Amp and Amp+ audio cards
  56  Load:   dtoverlay=hifiberry-amp
  57 --- /dev/null
  58 +++ b/arch/arm/boot/dts/overlays/hd44780-lcd-overlay.dts
  59 @@ -0,0 +1,46 @@
  60 +/dts-v1/;
  61 +/plugin/;
  62 +
  63 +/ {
  64 +    compatible = "brcm,bcm2835";
  65 +
  66 +    fragment@0 {
  67 +        target-path = "/";
  68 +        __overlay__ {
  69 +            lcd_screen: auxdisplay {
  70 +                compatible = "hit,hd44780";
  71 +
  72 +                data-gpios = <&gpio 6 0>,
  73 +                             <&gpio 13 0>,
  74 +                             <&gpio 19 0>,
  75 +                             <&gpio 26 0>;
  76 +                enable-gpios = <&gpio 21 0>;
  77 +                rs-gpios = <&gpio 20 0>;
  78 +
  79 +                display-height-chars = <2>;
  80 +                display-width-chars = <16>;
  81 +            };
  82 +
  83 +        };
  84 +    };
  85 +
  86 +    fragment@1 {
  87 +       target = <&lcd_screen>;
  88 +        __dormant__ {
  89 +            backlight-gpios = <&gpio 12 0>;
  90 +        };
  91 +    };
  92 +
  93 +    __overrides__ {
  94 +        pin_d4 = <&lcd_screen>,"data-gpios:4";
  95 +        pin_d5 = <&lcd_screen>,"data-gpios:16";
  96 +        pin_d6 = <&lcd_screen>,"data-gpios:28";
  97 +        pin_d7 = <&lcd_screen>,"data-gpios:40";
  98 +        pin_en = <&lcd_screen>,"enable-gpios:4";
  99 +        pin_rs = <&lcd_screen>,"rs-gpios:4";
 100 +        pin_bl = <0>,"+1", <&lcd_screen>,"backlight-gpios:4";
 101 +        display_height = <&lcd_screen>,"display-height-chars:0";
 102 +        display_width = <&lcd_screen>,"display-width-chars:0";
 103 +    };
 104 +
 105 +};