target/linux/bcm27xx/patches-5.15/950-0893-dtoverlays-Add-i2c-fan-overlay.patch

   1 From 4bf62f8dc97e24dadda64762ab47c299ac6eb8cb Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.com>
   3 Date: Tue, 3 May 2022 17:20:11 +0100
   4 Subject: [PATCH] dtoverlays: Add i2c-fan overlay
   5
   6 Add an i2c-fan overlay, initially with support for the EMC2301
   7 fan controller found on the CM4IO board.
   8 Based on the overlay from Traverse Technologies, but modified for
   9 the EMC2305 driver submitted to linux-hwmon.
  10
  11 Signed-off-by: Phil Elwell <phil@raspberrypi.com>
  12 ---
  13  arch/arm/boot/dts/overlays/Makefile           |  1 +
  14  arch/arm/boot/dts/overlays/README             | 33 +++++++
  15  .../arm/boot/dts/overlays/i2c-fan-overlay.dts | 92 +++++++++++++++++++
  16  3 files changed, 126 insertions(+)
  17  create mode 100644 arch/arm/boot/dts/overlays/i2c-fan-overlay.dts
  18
  19 --- a/arch/arm/boot/dts/overlays/Makefile
  20 +++ b/arch/arm/boot/dts/overlays/Makefile
  21 @@ -85,6 +85,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
  22         hy28b-2017.dtbo \
  23         i-sabre-q2m.dtbo \
  24         i2c-bcm2708.dtbo \
  25 +       i2c-fan.dtbo \
  26         i2c-gpio.dtbo \
  27         i2c-mux.dtbo \
  28         i2c-pwm-pca9685a.dtbo \
  29 --- a/arch/arm/boot/dts/overlays/README
  30 +++ b/arch/arm/boot/dts/overlays/README
  31 @@ -1530,6 +1530,39 @@ Load:   dtoverlay=i2c-bcm2708
  32  Params: <None>
  33
  34
  35 +Name:   i2c-fan
  36 +Info:   Adds support for a number of I2C fan controllers
  37 +Load:   dtoverlay=i2c-fan,<param>=<val>
  38 +Params: addr                    Sets the address for the fan controller. Note
  39 +                                that the device must be configured to use the
  40 +                                specified address.
  41 +
  42 +        i2c0                    Choose the I2C0 bus on GPIOs 0&1
  43 +
  44 +        i2c_csi_dsi             Choose the I2C0 bus on GPIOs 44&45
  45 +
  46 +        minpwm                  PWM setting for the fan when the SoC is below
  47 +                                mintemp (range 0-255. default 0)
  48 +        maxpwm                  PWM setting for the fan when the SoC is above
  49 +                                maxtemp (range 0-255. default 255)
  50 +        midtemp                 Temperature (in millicelcius) at which the fan
  51 +                                begins to speed up (default 50000)
  52 +
  53 +        midtemp_hyst            Temperature delta (in millicelcius) below
  54 +                                mintemp at which the fan will drop to minrpm
  55 +                                (default 2000)
  56 +
  57 +        maxtemp                 Temperature (in millicelcius) at which the fan
  58 +                                will be held at maxrpm (default 70000)
  59 +
  60 +        maxtemp_hyst            Temperature delta (in millicelcius) below
  61 +                                maxtemp at which the fan begins to slow down
  62 +                                (default 2000)
  63 +
  64 +        emc2301                 Select the Microchip EMC230x controller family
  65 +                                - EMC2301, EMC2302, EMC2303, EMC2305.
  66 +
  67 +
  68  Name:   i2c-gpio
  69  Info:   Adds support for software i2c controller on gpio pins
  70  Load:   dtoverlay=i2c-gpio,<param>=<val>
  71 --- /dev/null
  72 +++ b/arch/arm/boot/dts/overlays/i2c-fan-overlay.dts
  73 @@ -0,0 +1,92 @@
  74 +// Definitions for I2C based sensors using the Industrial IO or HWMON interface.
  75 +/dts-v1/;
  76 +/plugin/;
  77 +
  78 +#include <dt-bindings/thermal/thermal.h>
  79 +
  80 +/ {
  81 +       compatible = "brcm,bcm2835";
  82 +
  83 +       fragment@0 {
  84 +               target = <&i2cbus>;
  85 +               __dormant__ {
  86 +                       #address-cells = <1>;
  87 +                       #size-cells = <0>;
  88 +                       status = "okay";
  89 +
  90 +                       emc2301: emc2301@2f {
  91 +                               compatible = "microchip,emc2301";
  92 +                               reg = <0x2f>;
  93 +                               status = "okay";
  94 +                               #cooling-cells = <0x02>;
  95 +                       };
  96 +               };
  97 +       };
  98 +
  99 +       frag100: fragment@100 {
 100 +               target = <&i2c_arm>;
 101 +               i2cbus: __overlay__ {
 102 +                       status = "okay";
 103 +               };
 104 +       };
 105 +
 106 +       fragment@101 {
 107 +               target = <&i2c0if>;
 108 +               __dormant__ {
 109 +                       status = "okay";
 110 +               };
 111 +       };
 112 +
 113 +       fragment@102 {
 114 +               target = <&i2c0mux>;
 115 +               __dormant__ {
 116 +                       status = "okay";
 117 +               };
 118 +       };
 119 +
 120 +       fragment@103 {
 121 +               target = <&cpu_thermal>;
 122 +               polling-delay = <2000>; /* milliseconds */
 123 +               __overlay__ {
 124 +                       trips {
 125 +                               fanmid0: fanmid0 {
 126 +                                       temperature = <50000>;
 127 +                                       hysteresis = <2000>;
 128 +                                       type = "active";
 129 +                               };
 130 +                               fanmax0: fanmax0 {
 131 +                                       temperature = <75000>;
 132 +                                       hysteresis = <2000>;
 133 +                                       type = "active";
 134 +                               };
 135 +                       };
 136 +                       cooling-maps {
 137 +                               map0: map0 {
 138 +                                       trip = <&fanmid0>;
 139 +                                       cooling-device = <&emc2301 2 6>;
 140 +                               };
 141 +                               map1: map1 {
 142 +                                       trip = <&fanmax0>;
 143 +                                       cooling-device = <&emc2301 7 THERMAL_NO_LIMIT>;
 144 +                               };
 145 +                       };
 146 +               };
 147 +       };
 148 +
 149 +       __overrides__ {
 150 +               i2c0 =          <&frag100>,"target:0=",<&i2c0>;
 151 +               i2c_csi_dsi =   <&frag100>,"target:0=",<&i2c_csi_dsi>,
 152 +                               <0>,"+101+102";
 153 +               addr =          <&emc2301>,"reg:0";
 154 +               minpwm =        <&emc2301>,"emc2305,pwm-min;0";
 155 +               maxpwm =        <&emc2301>,"emc2305,pwm-max;0";
 156 +               midtemp =       <&fanmid0>,"temperature:0";
 157 +               midtemp_hyst =  <&fanmid0>,"hysteresis:0";
 158 +               maxtemp =       <&fanmax0>,"temperature:0";
 159 +               maxtemp_hyst =  <&fanmax0>,"hysteresis:0";
 160 +
 161 +               emc2301 =       <0>,"+0",
 162 +                               <&map0>,"cooling-device:0=",<&emc2301>,
 163 +                               <&map1>,"cooling-device:0=",<&emc2301>;
 164 +       };
 165 +};