target/linux/bcm27xx/patches-5.4/950-0931-overlays-Add-maxtherm-overlay-for-MAX6675-31855.patch

   1 From 56e726d1631c9551530b8db4127352c64c3cb94d Mon Sep 17 00:00:00 2001
   2 From: Dougie Lawson <dl1ims@gmail.com>
   3 Date: Mon, 27 Jul 2020 23:52:40 +0100
   4 Subject: [PATCH] overlays: Add maxtherm overlay for MAX6675/31855
   5
   6 Add an overlay - maxtherm - to support the MAX6675 and MAX31855 family
   7 of thermocouples.
   8
   9 Developed from an original set of overlays by Dougie Lawson.
  10
  11 See: https://github.com/raspberrypi/linux/pull/3763
  12
  13 Signed-off-by: Phil Elwell <phil@raspberrypi.com>
  14 ---
  15  arch/arm/boot/dts/overlays/Makefile           |   1 +
  16  arch/arm/boot/dts/overlays/README             |  30 ++++
  17  .../boot/dts/overlays/maxtherm-overlay.dts    | 166 ++++++++++++++++++
  18  3 files changed, 197 insertions(+)
  19  create mode 100644 arch/arm/boot/dts/overlays/maxtherm-overlay.dts
  20
  21 --- a/arch/arm/boot/dts/overlays/Makefile
  22 +++ b/arch/arm/boot/dts/overlays/Makefile
  23 @@ -98,6 +98,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
  24         justboom-digi.dtbo \
  25         ltc294x.dtbo \
  26         max98357a.dtbo \
  27 +       maxtherm.dtbo \
  28         mbed-dac.dtbo \
  29         mcp23017.dtbo \
  30         mcp23s17.dtbo \
  31 --- a/arch/arm/boot/dts/overlays/README
  32 +++ b/arch/arm/boot/dts/overlays/README
  33 @@ -1622,6 +1622,36 @@ Params: no-sdmode               Driver d
  34                                  of the DAC (default GPIO4 if parameter omitted).
  35
  36
  37 +Name:   maxtherm
  38 +Info:   Configure a MAX6675 or MAX31855 thermocouple as an IIO device.
  39 +
  40 +        For devices on spi1 or spi2, the interfaces should be enabled
  41 +        with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
  42 +        The overlay expects to disable the relevant spidev node, so also using
  43 +        e.g. cs0_spidev=off is unnecessary.
  44 +
  45 +        Note:   with the 5.7 kernel (and later) there will also be
  46 +                overlays for MAX31855E, MAX31855J, MAX31855K,
  47 +                MAX31885N, MAX31855R, MAX31855S and MAX31855T.
  48 +
  49 +        Example:
  50 +        MAX31855 on /dev/spidev0.0
  51 +            dtoverlay=maxtherm,spi0-0,max31855
  52 +
  53 +Load:   dtoverlay=maxtherm,<param>=<val>
  54 +Params: spi<n>-<m>              Configure device at spi<n>, cs<m>
  55 +                                (boolean, required)
  56 +        max6675                 Enable support for the MAX6675 (default)
  57 +        max31855                Enable support for the MAX31855
  58 +        max31855e               Enable support for the MAX31855E
  59 +        max31855j               Enable support for the MAX31855J
  60 +        max31855k               Enable support for the MAX31855K
  61 +        max31855n               Enable support for the MAX31855N
  62 +        max31855r               Enable support for the MAX31855R
  63 +        max31855s               Enable support for the MAX31855S
  64 +        max31855t               Enable support for the MAX31855T
  65 +
  66 +
  67  Name:   mbed-dac
  68  Info:   Configures the mbed AudioCODEC (TLV320AIC23B)
  69  Load:   dtoverlay=mbed-dac
  70 --- /dev/null
  71 +++ b/arch/arm/boot/dts/overlays/maxtherm-overlay.dts
  72 @@ -0,0 +1,166 @@
  73 +/*
  74 + * Universal device tree overlay for SPI devices
  75 + */
  76 +
  77 +/dts-v1/;
  78 +/plugin/;
  79 +
  80 +/ {
  81 +       compatible = "brcm,bcm2835";
  82 +
  83 +       fragment@0 {
  84 +               target = <&spidev0>;
  85 +               __dormant__ {
  86 +                       status = "disabled";
  87 +               };
  88 +       };
  89 +
  90 +       fragment@1 {
  91 +               target = <&spidev1>;
  92 +               __dormant__ {
  93 +                       status = "disabled";
  94 +               };
  95 +       };
  96 +
  97 +       fragment@2 {
  98 +               target-path = "spi1/spidev@0";
  99 +               __dormant__ {
 100 +                       status = "disabled";
 101 +               };
 102 +       };
 103 +
 104 +       fragment@3 {
 105 +               target-path = "spi1/spidev@1";
 106 +               __dormant__ {
 107 +                       status = "disabled";
 108 +               };
 109 +       };
 110 +
 111 +       fragment@4 {
 112 +               target-path = "spi1/spidev@2";
 113 +               __dormant__ {
 114 +                       status = "disabled";
 115 +               };
 116 +       };
 117 +
 118 +       fragment@5 {
 119 +               target-path = "spi2/spidev@0";
 120 +               __dormant__ {
 121 +                       status = "disabled";
 122 +               };
 123 +       };
 124 +
 125 +       fragment@6 {
 126 +               target-path = "spi2/spidev@1";
 127 +               __dormant__ {
 128 +                       status = "disabled";
 129 +               };
 130 +       };
 131 +
 132 +       fragment@7 {
 133 +               target-path = "spi2/spidev@2";
 134 +               __dormant__ {
 135 +                       status = "disabled";
 136 +               };
 137 +       };
 138 +
 139 +       maxfrag: fragment@8 {
 140 +               target = <&spi0>;
 141 +               __overlay__ {
 142 +                       status = "okay";
 143 +                       #address-cells = <1>;
 144 +                       #size-cells = <0>;
 145 +
 146 +                       max: maxtherm@0 {
 147 +                               compatible = "maxim,max6675";
 148 +                               reg = <0>;
 149 +                               spi-max-frequency = <500000>;
 150 +                       };
 151 +               };
 152 +       };
 153 +
 154 +       fragment@9 {
 155 +               target = <&max>;
 156 +               __dormant__ {
 157 +                       compatible = "maxim,max31855e", "maxim,max31855";
 158 +               };
 159 +       };
 160 +
 161 +       fragment@10 {
 162 +               target = <&max>;
 163 +               __dormant__ {
 164 +                       compatible = "maxim,max31855j", "maxim,max31855";
 165 +               };
 166 +       };
 167 +
 168 +       fragment@11 {
 169 +               target = <&max>;
 170 +               __dormant__ {
 171 +                       compatible = "maxim,max31855k", "maxim,max31855";
 172 +               };
 173 +       };
 174 +
 175 +       fragment@12 {
 176 +               target = <&max>;
 177 +               __dormant__ {
 178 +                       compatible = "maxim,max31855n", "maxim,max31855";
 179 +               };
 180 +       };
 181 +
 182 +       fragment@13 {
 183 +               target = <&max>;
 184 +               __dormant__ {
 185 +                       compatible = "maxim,max31855r", "maxim,max31855";
 186 +               };
 187 +       };
 188 +
 189 +       fragment@14 {
 190 +               target = <&max>;
 191 +               __dormant__ {
 192 +                       compatible = "maxim,max31855s", "maxim,max31855";
 193 +               };
 194 +       };
 195 +
 196 +       fragment@15 {
 197 +               target = <&max>;
 198 +               __dormant__ {
 199 +                       compatible = "maxim,max31855t", "maxim,max31855";
 200 +               };
 201 +       };
 202 +
 203 +       __overrides__ {
 204 +               spi0-0 = <0>, "+0",
 205 +                        <&maxfrag>,"target:0=",<&spi0>,
 206 +                        <&max>,"reg:0=0";
 207 +               spi0-1 = <0>, "+1",
 208 +                        <&maxfrag>,"target:0=",<&spi0>,
 209 +                        <&max>,"reg:0=1";
 210 +               spi1-0 = <0>, "+2",
 211 +                        <&maxfrag>,"target:0=",<&spi1>,
 212 +                        <&max>,"reg:0=0";
 213 +               spi1-1 = <0>, "+3",
 214 +                        <&maxfrag>,"target:0=",<&spi1>,
 215 +                        <&max>,"reg:0=1";
 216 +               spi1-2 = <0>, "+4",
 217 +                        <&maxfrag>,"target:0=",<&spi1>,
 218 +                        <&max>,"reg:0=2";
 219 +               spi2-0 = <0>, "+5",
 220 +                        <&maxfrag>,"target:0=",<&spi2>,
 221 +                        <&max>,"reg:0=0";
 222 +               spi2-1 = <0>, "+6",
 223 +                        <&maxfrag>,"target:0=",<&spi2>,
 224 +                        <&max>,"reg:0=1";
 225 +               spi2-2 = <0>, "+7",
 226 +                        <&maxfrag>,"target:0=",<&spi2>,
 227 +                        <&max>,"reg:0=2";
 228 +               max6675 = <&max>,"compatible=maxim,max6675";
 229 +               max31855 = <&max>,"compatible=maxim,max31855";
 230 +               max31855e = <0>,"+9";
 231 +               max31855j = <0>,"+10";
 232 +               max31855k = <0>,"+11";
 233 +               max31855n = <0>,"+12";
 234 +               max31855r = <0>,"+13";
 235 +               max31855s = <0>,"+14";
 236 +               max31855t = <0>,"+15";
 237 +       };
 238 +};