git.openwrt.org Git - openwrt/staging/stintel.git/blob

   1 From 99f2ab0dad947049e0fa62e88c1e4c1feb7ab379 Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.com>
   3 Date: Thu, 4 Feb 2021 14:41:10 +0000
   4 Subject: [PATCH] dtoverlays: Add an overlay for the VGA666 when used
   5  with vc4-kms-v3d
   6
   7 Includes optional use of GPIOs 0&1 / BSC0 for DDC to read the EDID
   8 from the display.
   9
  10 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
  11 ---
  12  arch/arm/boot/dts/overlays/Makefile           |   1 +
  13  arch/arm/boot/dts/overlays/README             |  10 ++
  14  .../dts/overlays/vc4-kms-vga666-overlay.dts   | 100 ++++++++++++++++++
  15  3 files changed, 111 insertions(+)
  16  create mode 100644 arch/arm/boot/dts/overlays/vc4-kms-vga666-overlay.dts
  17
  18 --- a/arch/arm/boot/dts/overlays/Makefile
  19 +++ b/arch/arm/boot/dts/overlays/Makefile
  20 @@ -211,6 +211,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
  21         vc4-kms-kippah-7inch.dtbo \
  22         vc4-kms-v3d.dtbo \
  23         vc4-kms-v3d-pi4.dtbo \
  24 +       vc4-kms-vga666.dtbo \
  25         vga666.dtbo \
  26         w1-gpio.dtbo \
  27         w1-gpio-pullup.dtbo \
  28 --- a/arch/arm/boot/dts/overlays/README
  29 +++ b/arch/arm/boot/dts/overlays/README
  30 @@ -3120,10 +3120,20 @@ Params: cma-512                 CMA is 5
  31                                  outputs)
  32
  33
  34 +Name:   vc4-kms-vga666
  35 +Info:   Enable the VGA666 (resistor ladder ADC) for the vc4-kms-v3d driver.
  36 +        Requires vc4-kms-v3d to be loaded.
  37 +Load:   dtoverlay=vc4-kms-vga666,<param>
  38 +Params: ddc                     Enables GPIOs 0&1 as the I2C to read the EDID
  39 +                                from the display. NB These are NOT 5V tolerant
  40 +                                GPIOs, therefore level shifters are required.
  41 +
  42 +
  43  Name:   vga666
  44  Info:   Overlay for the Fen Logic VGA666 board
  45          This uses GPIOs 2-21 (so no I2C), and activates the output 2-3 seconds
  46          after the kernel has started.
  47 +        NOT for use with vc4-kms-v3d.
  48  Load:   dtoverlay=vga666
  49  Params: <None>
  50
  51 --- /dev/null
  52 +++ b/arch/arm/boot/dts/overlays/vc4-kms-vga666-overlay.dts
  53 @@ -0,0 +1,100 @@
  54 +/*
  55 + * vc4-kms-vga666-overlay.dts
  56 + * Configures a FenLogic or similar VGA666 DPI adapter when using the
  57 + * vc4-kms-v3d driver.
  58 + * If a suitable I2C level shifter is connected to GPIOs 0&1 and the VGA
  59 + * ID1/SDA (pin 12) and ID3/SCL (pin 15) lines, then there is the option to
  60 + * enable reading the EDID from the display.
  61 + */
  62 +
  63 +/dts-v1/;
  64 +/plugin/;
  65 +
  66 +#include <dt-bindings/pinctrl/bcm2835.h>
  67 +
  68 +/ {
  69 +       compatible = "brcm,bcm2835";
  70 +
  71 +       fragment@0 {
  72 +               target-path = "/";
  73 +               __overlay__ {
  74 +                       vga_connector: vga_connector {
  75 +                               compatible = "vga-connector";
  76 +                               label = "vga";
  77 +
  78 +                               port {
  79 +                                       vga_con_in: endpoint {
  80 +                                               remote-endpoint = <&vga666_out>;
  81 +                                       };
  82 +                               };
  83 +                       };
  84 +
  85 +                       vga_dac {
  86 +                               compatible = "dumb-vga-dac";
  87 +
  88 +                               ports {
  89 +                                       #address-cells = <1>;
  90 +                                       #size-cells = <0>;
  91 +
  92 +                                       port@0 {
  93 +                                               reg = <0>;
  94 +
  95 +                                               vga666_in: endpoint {
  96 +                                                       remote-endpoint = <&dpi_out>;
  97 +                                               };
  98 +                                       };
  99 +
 100 +                                       port@1 {
 101 +                                               reg = <1>;
 102 +
 103 +                                               vga666_out: endpoint {
 104 +                                                       remote-endpoint = <&vga_con_in>;
 105 +                                               };
 106 +                                       };
 107 +                               };
 108 +                       };
 109 +
 110 +               };
 111 +       };
 112 +
 113 +       fragment@1 {
 114 +               target = <&dpi>;
 115 +               __overlay__  {
 116 +                       status = "okay";
 117 +
 118 +                       pinctrl-names = "default";
 119 +                       pinctrl-0 = <&dpi_18bit_gpio2>;
 120 +
 121 +                       port {
 122 +                               dpi_out: endpoint@0 {
 123 +                                       remote-endpoint = <&vga666_in>;
 124 +                               };
 125 +                       };
 126 +               };
 127 +       };
 128 +
 129 +       fragment@2 {
 130 +               target = <&vga_connector>;
 131 +               __dormant__  {
 132 +                       ddc-i2c-bus = <&i2c_vc>;
 133 +               };
 134 +       };
 135 +
 136 +       fragment@3 {
 137 +               target = <&i2c0if>;
 138 +               __dormant__ {
 139 +                       status = "okay";
 140 +               };
 141 +       };
 142 +
 143 +       fragment@4 {
 144 +               target = <&i2c0mux>;
 145 +               __dormant__ {
 146 +                       status = "okay";
 147 +               };
 148 +       };
 149 +
 150 +       __overrides__ {
 151 +               ddc = <0>,"=2", <0>,"=3", <0>,"=4";
 152 +       };
 153 +};