target/linux/bcm27xx/patches-5.10/950-0373-overlays-Add-MAX31856-support-to-maxtherm-overlay.patch

   1 From 9444edfa8b5b18f8727b82853dd50345a400a316 Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.com>
   3 Date: Thu, 22 Oct 2020 17:11:12 +0100
   4 Subject: [PATCH] overlays: Add MAX31856 support to maxtherm overlay
   5
   6 Extend the maxtherm overlay with support for the MAX31856.
   7 The driver reads the thermocouple type from a property, which is much
   8 more civilised.
   9
  10 See: https://github.com/raspberrypi/linux/issues/3915
  11
  12 Signed-off-by: Phil Elwell <phil@raspberrypi.com>
  13 ---
  14  arch/arm/boot/dts/overlays/README             | 18 ++++++++++++-----
  15  .../boot/dts/overlays/maxtherm-overlay.dts    | 20 +++++++++++++++++++
  16  2 files changed, 33 insertions(+), 5 deletions(-)
  17
  18 --- a/arch/arm/boot/dts/overlays/README
  19 +++ b/arch/arm/boot/dts/overlays/README
  20 @@ -1666,20 +1666,19 @@ Params: no-sdmode               Driver d
  21
  22
  23  Name:   maxtherm
  24 -Info:   Configure a MAX6675 or MAX31855 thermocouple as an IIO device.
  25 +Info:   Configure a MAX6675, MAX31855 or MAX31856 thermocouple as an IIO device.
  26
  27          For devices on spi1 or spi2, the interfaces should be enabled
  28          with one of the spi1-1/2/3cs and/or spi2-1/2/3cs overlays.
  29          The overlay expects to disable the relevant spidev node, so also using
  30          e.g. cs0_spidev=off is unnecessary.
  31
  32 -        Note:   with the 5.7 kernel (and later) there will also be
  33 -                overlays for MAX31855E, MAX31855J, MAX31855K,
  34 -                MAX31885N, MAX31855R, MAX31855S and MAX31855T.
  35 -
  36          Example:
  37          MAX31855 on /dev/spidev0.0
  38              dtoverlay=maxtherm,spi0-0,max31855
  39 +        MAX31856 using a type J thermocouple on /dev/spidev2.1
  40 +            dtoverlay=spi2-2cs
  41 +            dtoverlay=maxtherm,spi2-1,max31856,type_j
  42
  43  Load:   dtoverlay=maxtherm,<param>=<val>
  44  Params: spi<n>-<m>              Configure device at spi<n>, cs<m>
  45 @@ -1693,6 +1692,15 @@ Params: spi<n>-<m>              Configur
  46          max31855r               Enable support for the MAX31855R
  47          max31855s               Enable support for the MAX31855S
  48          max31855t               Enable support for the MAX31855T
  49 +        max31856                Enable support for the MAX31856 (with type K)
  50 +        type_b                  Select a type B sensor for max31856
  51 +        type_e                  Select a type E sensor for max31856
  52 +        type_j                  Select a type J sensor for max31856
  53 +        type_k                  Select a type K sensor for max31856
  54 +        type_n                  Select a type N sensor for max31856
  55 +        type_r                  Select a type R sensor for max31856
  56 +        type_s                  Select a type S sensor for max31856
  57 +        type_t                  Select a type T sensor for max31856
  58
  59
  60  Name:   mbed-dac
  61 --- a/arch/arm/boot/dts/overlays/maxtherm-overlay.dts
  62 +++ b/arch/arm/boot/dts/overlays/maxtherm-overlay.dts
  63 @@ -5,6 +5,8 @@
  64  /dts-v1/;
  65  /plugin/;
  66
  67 +#include <dt-bindings/iio/temperature/thermocouple.h>
  68 +
  69  / {
  70         compatible = "brcm,bcm2835";
  71
  72 @@ -128,6 +130,15 @@
  73                 };
  74         };
  75
  76 +       fragment@16 {
  77 +               target = <&max>;
  78 +               __dormant__ {
  79 +                       compatible = "maxim,max31856";
  80 +                       spi-cpha;
  81 +                       thermocouple-type = <THERMOCOUPLE_TYPE_K>;
  82 +               };
  83 +       };
  84 +
  85         __overrides__ {
  86                 spi0-0 = <0>, "+0",
  87                          <&maxfrag>,"target:0=",<&spi0>,
  88 @@ -162,5 +173,14 @@
  89                 max31855r = <0>,"+13";
  90                 max31855s = <0>,"+14";
  91                 max31855t = <0>,"+15";
  92 +               max31856  = <0>,"+16";
  93 +               type_b    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_B>;
  94 +               type_e    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_E>;
  95 +               type_j    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_J>;
  96 +               type_k    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_K>;
  97 +               type_n    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_N>;
  98 +               type_r    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_R>;
  99 +               type_s    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_S>;
 100 +               type_t    = <&max>,"thermocouple-type:0=",<THERMOCOUPLE_TYPE_T>;
 101         };
 102  };