target/linux/brcm2708/patches-4.4/0161-DT-Add-overlays-to-configure-I2C-pins.patch

   1 From 2d787b8c422a777f688b185420268dc618d995e4 Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <6by9@users.noreply.github.com>
   3 Date: Mon, 8 Feb 2016 23:49:41 +0000
   4 Subject: [PATCH 161/304] DT: Add overlays to configure I2C pins
   5
   6 Lifted from
   7 https://www.raspberrypi.org/forums/viewtopic.php?f=107&t=120938&p=825883
   8 so not claiming this to be my own work.
   9 Adds overlays i2c0-bcm2708 and i2c1-bcm2708 that allow the pin
  10 allocations for i2c-0 and i2c-1 to be changed.
  11 ---
  12  arch/arm/boot/dts/overlays/Makefile                |  2 ++
  13  arch/arm/boot/dts/overlays/README                  | 16 ++++++++++
  14  .../arm/boot/dts/overlays/i2c0-bcm2708-overlay.dts | 36 +++++++++++++++++++++
  15  .../arm/boot/dts/overlays/i2c1-bcm2708-overlay.dts | 37 ++++++++++++++++++++++
  16  4 files changed, 91 insertions(+)
  17  create mode 100644 arch/arm/boot/dts/overlays/i2c0-bcm2708-overlay.dts
  18  create mode 100644 arch/arm/boot/dts/overlays/i2c1-bcm2708-overlay.dts
  19
  20 --- a/arch/arm/boot/dts/overlays/Makefile
  21 +++ b/arch/arm/boot/dts/overlays/Makefile
  22 @@ -29,6 +29,8 @@ dtb-$(RPI_DT_OVERLAYS) += hy28a-overlay.
  23  dtb-$(RPI_DT_OVERLAYS) += hy28b-overlay.dtb
  24  dtb-$(RPI_DT_OVERLAYS) += i2c-rtc-overlay.dtb
  25  dtb-$(RPI_DT_OVERLAYS) += i2c-gpio-overlay.dtb
  26 +dtb-$(RPI_DT_OVERLAYS) += i2c0-bcm2708-overlay.dtb
  27 +dtb-$(RPI_DT_OVERLAYS) += i2c1-bcm2708-overlay.dtb
  28  dtb-$(RPI_DT_OVERLAYS) += i2s-mmap-overlay.dtb
  29  dtb-$(RPI_DT_OVERLAYS) += iqaudio-dac-overlay.dtb
  30  dtb-$(RPI_DT_OVERLAYS) += iqaudio-dacplus-overlay.dtb
  31 --- a/arch/arm/boot/dts/overlays/README
  32 +++ b/arch/arm/boot/dts/overlays/README
  33 @@ -371,6 +371,22 @@ Params: ds1307                  Select t
  34          pcf8563                 Select the PCF8563 device
  35
  36
  37 +Name:   i2c0-bcm2708
  38 +Info:   Enable the i2c_bcm2708 driver for the i2c0 bus
  39 +Load:   dtoverlay=i2c0-bcm2708,<param>=<val>
  40 +Params: sda0_pin                GPIO pin for SDA0 (0, 28 [or 44] - default 0)
  41 +        scl0_pin                GPIO pin for SCL0 (1, 29 [or 45] - default 1)
  42 +
  43 +
  44 +Name:   i2c1-bcm2708
  45 +Info:   Enable the i2c_bcm2708 driver for the i2c1 bus
  46 +Load:   dtoverlay=i2c1-bcm2708,<param>=<val>
  47 +Params: sda1_pin                GPIO pin for SDA1 (2 or 44 - default 2)
  48 +        scl1_pin                GPIO pin for SCL1 (3 or 45 - default 3)
  49 +        pin_func                Alternative pin function (4 (alt0), 6 (alt2) -
  50 +                                default 4)
  51 +
  52 +
  53  Name:   i2s-mmap
  54  Info:   Enables mmap support in the bcm2708-i2s driver
  55  Load:   dtoverlay=i2s-mmap
  56 --- /dev/null
  57 +++ b/arch/arm/boot/dts/overlays/i2c0-bcm2708-overlay.dts
  58 @@ -0,0 +1,36 @@
  59 +/*
  60 + * Device tree overlay for i2c_bcm2708, i2c0 bus
  61 + *
  62 + * Compile:
  63 + * dtc -@ -I dts -O dtb -o i2c0-bcm2708-overlay.dtb i2c0-bcm2708-overlay.dts
  64 + */
  65 +
  66 +/dts-v1/;
  67 +/plugin/;
  68 +
  69 +/{
  70 +   compatible = "brcm,bcm2708";
  71 +
  72 +   fragment@0 {
  73 +      target = <&i2c0>;
  74 +      __overlay__ {
  75 +         pinctrl-0 = <&i2c0_pins>;
  76 +         status = "okay";
  77 +      };
  78 +   };
  79 +
  80 +   fragment@1 {
  81 +      target = <&gpio>;
  82 +      __overlay__ {
  83 +         i2c0_pins: i2c0 {
  84 +            brcm,pins = <0 1>;
  85 +            brcm,function = <4>; /* alt0 */
  86 +         };
  87 +      };
  88 +   };
  89 +
  90 +   __overrides__ {
  91 +      sda0_pin = <&i2c0_pins>,"brcm,pins:0";
  92 +      scl0_pin = <&i2c0_pins>,"brcm,pins:4";
  93 +   };
  94 +};
  95 --- /dev/null
  96 +++ b/arch/arm/boot/dts/overlays/i2c1-bcm2708-overlay.dts
  97 @@ -0,0 +1,37 @@
  98 +/*
  99 + * Device tree overlay for i2c_bcm2708, i2c1 bus
 100 + *
 101 + * Compile:
 102 + * dtc -@ -I dts -O dtb -o i2c1-bcm2708-overlay.dtb i2c1-bcm2708-overlay.dts
 103 + */
 104 +
 105 +/dts-v1/;
 106 +/plugin/;
 107 +
 108 +/{
 109 +   compatible = "brcm,bcm2708";
 110 +
 111 +   fragment@0 {
 112 +      target = <&i2c1>;
 113 +      __overlay__ {
 114 +         pinctrl-0 = <&i2c1_pins>;
 115 +         status = "okay";
 116 +      };
 117 +   };
 118 +
 119 +   fragment@1 {
 120 +      target = <&gpio>;
 121 +      __overlay__ {
 122 +         i2c1_pins: i2c1 {
 123 +            brcm,pins = <2 3>;
 124 +            brcm,function = <4>; /* alt0 */
 125 +         };
 126 +      };
 127 +   };
 128 +
 129 +   __overrides__ {
 130 +      sda1_pin = <&i2c1_pins>,"brcm,pins:0";
 131 +      scl1_pin = <&i2c1_pins>,"brcm,pins:4";
 132 +      pin_func = <&i2c1_pins>,"brcm,function:0";
 133 +   };
 134 +};