target/linux/brcm2708/patches-4.4/0107-Build-i2c_gpio-module-and-add-a-device-tree-overlay-.patch

   1 From 5371d757db191f77f115b1248184e2f1a15dfa4b 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 107/127] 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               | 13 +++++++++++-
  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, 43 insertions(+), 1 deletion(-)
  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 @@ -287,9 +287,20 @@ 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>=<val>
  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 +Load:   dtoverlay=i2c-rtc,<param>=<val>
  47  Params: ds1307                   Select the DS1307 device
  48
  49          ds3231                   Select the DS3231 device
  50 --- /dev/null
  51 +++ b/arch/arm/boot/dts/overlays/i2c-gpio-overlay.dts
  52 @@ -0,0 +1,28 @@
  53 +// Overlay for i2c_gpio bitbanging host bus.
  54 +/dts-v1/;
  55 +/plugin/;
  56 +
  57 +/ {
  58 +       compatible = "brcm,bcm2708";
  59 +
  60 +       fragment@0 {
  61 +               target-path = "/";
  62 +               __overlay__ {
  63 +                       i2c_gpio: i2c@0 {
  64 +                               compatible = "i2c-gpio";
  65 +                               gpios = <&gpio 23 0 /* sda */
  66 +                                        &gpio 24 0 /* scl */
  67 +                                       >;
  68 +                               i2c-gpio,delay-us = <2>;        /* ~100 kHz */
  69 +                               #address-cells = <1>;
  70 +                               #size-cells = <0>;
  71 +                       };
  72 +               };
  73 +       };
  74 +       __overrides__ {
  75 +               i2c_gpio_sda = <&i2c_gpio>,"gpios:4";
  76 +               i2c_gpio_scl = <&i2c_gpio>,"gpios:16";
  77 +               i2c_gpio_delay_us = <&i2c_gpio>,"i2c-gpio,delay-us:0";
  78 +       };
  79 +};
  80 +
  81 --- a/arch/arm/configs/bcm2709_defconfig
  82 +++ b/arch/arm/configs/bcm2709_defconfig
  83 @@ -595,6 +595,7 @@ CONFIG_RAW_DRIVER=y
  84  CONFIG_I2C=y
  85  CONFIG_I2C_CHARDEV=m
  86  CONFIG_I2C_BCM2708=m
  87 +CONFIG_I2C_GPIO=m
  88  CONFIG_SPI=y
  89  CONFIG_SPI_BCM2835=m
  90  CONFIG_SPI_SPIDEV=y
  91 --- a/arch/arm/configs/bcmrpi_defconfig
  92 +++ b/arch/arm/configs/bcmrpi_defconfig
  93 @@ -588,6 +588,7 @@ CONFIG_RAW_DRIVER=y
  94  CONFIG_I2C=y
  95  CONFIG_I2C_CHARDEV=m
  96  CONFIG_I2C_BCM2708=m
  97 +CONFIG_I2C_GPIO=m
  98  CONFIG_SPI=y
  99  CONFIG_SPI_BCM2835=m
 100  CONFIG_SPI_SPIDEV=y