target/linux/brcm2708/patches-4.14/950-0289-overlays-Add-ltc294x-battery-gauge.patch

   1 From 585ea300fa44cdf3c3259af68c49518bb85e4af2 Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.org>
   3 Date: Tue, 1 May 2018 09:35:56 +0100
   4 Subject: [PATCH 289/454] overlays: Add ltc294x (battery gauge)
   5
   6 Support the LTC294x range of I2C-connected battery monitors.
   7
   8 See: https://github.com/raspberrypi/linux/issues/2537
   9
  10 Signed-off-by: Phil Elwell <phil@raspberrypi.org>
  11 ---
  12  arch/arm/boot/dts/overlays/Makefile           |  1 +
  13  arch/arm/boot/dts/overlays/README             | 25 ++++++
  14  .../arm/boot/dts/overlays/ltc294x-overlay.dts | 86 +++++++++++++++++++
  15  3 files changed, 112 insertions(+)
  16  create mode 100644 arch/arm/boot/dts/overlays/ltc294x-overlay.dts
  17
  18 --- a/arch/arm/boot/dts/overlays/Makefile
  19 +++ b/arch/arm/boot/dts/overlays/Makefile
  20 @@ -60,6 +60,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
  21         justboom-dac.dtbo \
  22         justboom-digi.dtbo \
  23         lirc-rpi.dtbo \
  24 +       ltc294x.dtbo \
  25         mbed-dac.dtbo \
  26         mcp23017.dtbo \
  27         mcp23s17.dtbo \
  28 --- a/arch/arm/boot/dts/overlays/README
  29 +++ b/arch/arm/boot/dts/overlays/README
  30 @@ -1020,6 +1020,31 @@ Params: gpio_out_pin            GPIO for
  31                                  (default "off")
  32
  33
  34 +Name:   ltc294x
  35 +Info:   Adds support for the ltc294x family of battery gauges
  36 +Load:   dtoverlay=ltc294x,<param>=<val>
  37 +Params: ltc2941                 Select the ltc2941 device
  38 +
  39 +        ltc2942                 Select the ltc2942 device
  40 +
  41 +        ltc2943                 Select the ltc2943 device
  42 +
  43 +        ltc2944                 Select the ltc2944 device
  44 +
  45 +        resistor-sense          The sense resistor value in milli-ohms.
  46 +                                Can be a 32-bit negative value when the battery
  47 +                                has been connected to the wrong end of the
  48 +                                resistor.
  49 +
  50 +        prescaler-exponent      Range and accuracy of the gauge. The value is
  51 +                                programmed into the chip only if it differs
  52 +                                from the current setting.
  53 +                                For LTC2941 only:
  54 +                                - Default value is 128
  55 +                                - the exponent is in the range 0-7 (default 7)
  56 +                                See the datasheet for more information.
  57 +
  58 +
  59  Name:   mbed-dac
  60  Info:   Configures the mbed AudioCODEC (TLV320AIC23B)
  61  Load:   dtoverlay=mbed-dac
  62 --- /dev/null
  63 +++ b/arch/arm/boot/dts/overlays/ltc294x-overlay.dts
  64 @@ -0,0 +1,86 @@
  65 +/dts-v1/;
  66 +/plugin/;
  67 +
  68 +
  69 +/ {
  70 +       compatible = "brcm,bcm2835";
  71 +
  72 +       fragment@0 {
  73 +               target = <&i2c_arm>;
  74 +               __dormant__ {
  75 +                       #address-cells = <1>;
  76 +                       #size-cells = <0>;
  77 +                       status = "okay";
  78 +
  79 +                       ltc2941: ltc2941@64 {
  80 +                               compatible = "lltc,ltc2941";
  81 +                               reg = <0x64>;
  82 +                               lltc,resistor-sense = <50>;
  83 +                               lltc,prescaler-exponent = <7>;
  84 +                       };
  85 +               };
  86 +       };
  87 +
  88 +       fragment@1 {
  89 +               target = <&i2c_arm>;
  90 +               __dormant__ {
  91 +                       #address-cells = <1>;
  92 +                       #size-cells = <0>;
  93 +                       status = "okay";
  94 +
  95 +                       ltc2942: ltc2942@64 {
  96 +                               compatible = "lltc,ltc2942";
  97 +                               reg = <0x64>;
  98 +                               lltc,resistor-sense = <50>;
  99 +                               lltc,prescaler-exponent = <7>;
 100 +                       };
 101 +               };
 102 +       };
 103 +
 104 +       fragment@2 {
 105 +               target = <&i2c_arm>;
 106 +               __dormant__ {
 107 +                       #address-cells = <1>;
 108 +                       #size-cells = <0>;
 109 +                       status = "okay";
 110 +
 111 +                       ltc2943: ltc2943@64 {
 112 +                               compatible = "lltc,ltc2943";
 113 +                               reg = <0x64>;
 114 +                               lltc,resistor-sense = <50>;
 115 +                               lltc,prescaler-exponent = <7>;
 116 +                       };
 117 +               };
 118 +       };
 119 +
 120 +       fragment@3 {
 121 +               target = <&i2c_arm>;
 122 +               __dormant__ {
 123 +                       #address-cells = <1>;
 124 +                       #size-cells = <0>;
 125 +                       status = "okay";
 126 +
 127 +                       ltc2944: ltc2944@64 {
 128 +                               compatible = "lltc,ltc2944";
 129 +                               reg = <0x64>;
 130 +                               lltc,resistor-sense = <50>;
 131 +                               lltc,prescaler-exponent = <7>;
 132 +                       };
 133 +               };
 134 +       };
 135 +
 136 +       __overrides__ {
 137 +               ltc2941 = <0>,"+0";
 138 +               ltc2942 = <0>,"+1";
 139 +               ltc2943 = <0>,"+2";
 140 +               ltc2944 = <0>,"+3";
 141 +               resistor-sense = <&ltc2941>, "lltc,resistor-sense:0",
 142 +                                <&ltc2942>, "lltc,resistor-sense:0",
 143 +                                <&ltc2943>, "lltc,resistor-sense:0",
 144 +                                <&ltc2944>, "lltc,resistor-sense:0";
 145 +               prescaler-exponent = <&ltc2941>, "lltc,prescaler-exponent:0",
 146 +                                <&ltc2942>, "lltc,prescaler-exponent:0",
 147 +                                <&ltc2943>, "lltc,prescaler-exponent:0",
 148 +                                <&ltc2944>, "lltc,prescaler-exponent:0";
 149 +       };
 150 +};