target/linux/brcm2708/patches-4.1/0209-Build-i2c_gpio-module-and-add-a-device-tree-overlay-.patch

   1 From 43833958324dc349e49c0e4e2fa6fe36ebc7508d Mon Sep 17 00:00:00 2001
   2 From: Alistair Buxton <a.j.buxton@gmail.com>
   3 Date: Sun, 1 Nov 2015 22:27:56 +0000
   4 Subject: [PATCH 209/222] Build i2c_gpio module and add a device tree overlay
   5  to configure it.
   6
   7 ---
   8  arch/arm/boot/dts/overlays/Makefile             |  1 +
   9  arch/arm/boot/dts/overlays/README               | 11 ++++++++++
  10  arch/arm/boot/dts/overlays/i2c-gpio-overlay.dts | 28 +++++++++++++++++++++++++
  11  arch/arm/configs/bcm2709_defconfig              |  1 +
  12  arch/arm/configs/bcmrpi_defconfig               |  1 +
  13  5 files changed, 42 insertions(+)
  14  create mode 100644 arch/arm/boot/dts/overlays/i2c-gpio-overlay.dts
  15
  16 --- a/arch/arm/boot/dts/overlays/Makefile
  17 +++ b/arch/arm/boot/dts/overlays/Makefile
  18 @@ -25,6 +25,7 @@ dtb-$(RPI_DT_OVERLAYS) += hifiberry-digi
  19  dtb-$(RPI_DT_OVERLAYS) += hy28a-overlay.dtb
  20  dtb-$(RPI_DT_OVERLAYS) += hy28b-overlay.dtb
  21  dtb-$(RPI_DT_OVERLAYS) += i2c-rtc-overlay.dtb
  22 +dtb-$(RPI_DT_OVERLAYS) += i2c-gpio-overlay.dtb
  23  dtb-$(RPI_DT_OVERLAYS) += i2s-mmap-overlay.dtb
  24  dtb-$(RPI_DT_OVERLAYS) += iqaudio-dac-overlay.dtb
  25  dtb-$(RPI_DT_OVERLAYS) += iqaudio-dacplus-overlay.dtb
  26 --- a/arch/arm/boot/dts/overlays/README
  27 +++ b/arch/arm/boot/dts/overlays/README
  28 @@ -284,6 +284,17 @@ Params: speed                    Display
  29          ledgpio                  GPIO used to control backlight
  30
  31
  32 +Name:   i2c-gpio
  33 +Info:   Adds support for software i2c controller on gpio pins
  34 +Load:   dtoverlay=i2c-gpio,<param>
  35 +Params: i2c_gpio_sda             GPIO used for I2C data (default "23")
  36 +
  37 +        i2c_gpio_scl             GPIO used for I2C clock (default "24")
  38 +
  39 +        i2c_gpio_delay_us        Clock delay in microseconds
  40 +                                 (default "2" = ~100kHz)
  41 +
  42 +
  43  Name:   i2c-rtc
  44  Info:   Adds support for a number of I2C Real Time Clock devices
  45  Load:   dtoverlay=i2c-rtc,<param>
  46 --- /dev/null
  47 +++ b/arch/arm/boot/dts/overlays/i2c-gpio-overlay.dts
  48 @@ -0,0 +1,28 @@
  49 +// Overlay for i2c_gpio bitbanging host bus.
  50 +/dts-v1/;
  51 +/plugin/;
  52 +
  53 +/ {
  54 +       compatible = "brcm,bcm2708";
  55 +
  56 +       fragment@0 {
  57 +               target-path = "/";
  58 +               __overlay__ {
  59 +                       i2c_gpio: i2c@0 {
  60 +                               compatible = "i2c-gpio";
  61 +                               gpios = <&gpio 23 0 /* sda */
  62 +                                        &gpio 24 0 /* scl */
  63 +                                       >;
  64 +                               i2c-gpio,delay-us = <2>;        /* ~100 kHz */
  65 +                               #address-cells = <1>;
  66 +                               #size-cells = <0>;
  67 +                       };
  68 +               };
  69 +       };
  70 +       __overrides__ {
  71 +               i2c_gpio_sda = <&i2c_gpio>,"gpios:4";
  72 +               i2c_gpio_scl = <&i2c_gpio>,"gpios:16";
  73 +               i2c_gpio_delay_us = <&i2c_gpio>,"i2c-gpio,delay-us:0";
  74 +       };
  75 +};
  76 +
  77 --- a/arch/arm/configs/bcm2709_defconfig
  78 +++ b/arch/arm/configs/bcm2709_defconfig
  79 @@ -593,6 +593,7 @@ CONFIG_BCM_VC_SM=y
  80  CONFIG_I2C=y
  81  CONFIG_I2C_CHARDEV=m
  82  CONFIG_I2C_BCM2708=m
  83 +CONFIG_I2C_GPIO=m
  84  CONFIG_SPI=y
  85  CONFIG_SPI_BCM2835=m
  86  CONFIG_SPI_BCM2708=m
  87 --- a/arch/arm/configs/bcmrpi_defconfig
  88 +++ b/arch/arm/configs/bcmrpi_defconfig
  89 @@ -586,6 +586,7 @@ CONFIG_BCM_VC_SM=y
  90  CONFIG_I2C=y
  91  CONFIG_I2C_CHARDEV=m
  92  CONFIG_I2C_BCM2708=m
  93 +CONFIG_I2C_GPIO=m
  94  CONFIG_SPI=y
  95  CONFIG_SPI_BCM2835=m
  96  CONFIG_SPI_BCM2708=m