target/linux/brcm2708/patches-4.14/950-0412-PoE-HAT-driver-cleanup.patch

   1 From 97a6a1f61eb949892457a739435fd5280fc800f8 Mon Sep 17 00:00:00 2001
   2 From: XECDesign <XECDesign@users.noreply.github.com>
   3 Date: Wed, 29 Aug 2018 15:08:30 +0100
   4 Subject: [PATCH 412/454] PoE HAT driver cleanup
   5
   6 * Fix undeclared variable in rpi_poe_fan_suspend
   7 * Add SPDX-License-Identifier
   8 * Expand PoE acronym in Kconfig help
   9 * Give clearer error message on of_property_count_u32_elems fail
  10 * Add documentation
  11 * Add vendor to of_device_id compatible string.
  12 * Rename m_data_s struct to fw_data_s
  13 * Fix typos
  14
  15 Fixes: #2665
  16
  17 Signed-off-by: Serge Schneider <serge@raspberrypi.org>
  18 ---
  19  .../devicetree/bindings/hwmon/rpi-poe-fan.txt | 55 +++++++++++++++++++
  20  Documentation/hwmon/rpi-poe-fan               | 15 +++++
  21  .../arm/boot/dts/overlays/rpi-poe-overlay.dts |  2 +-
  22  drivers/hwmon/Kconfig                         |  5 +-
  23  drivers/hwmon/rpi-poe-fan.c                   | 39 ++++++-------
  24  5 files changed, 90 insertions(+), 26 deletions(-)
  25  create mode 100644 Documentation/devicetree/bindings/hwmon/rpi-poe-fan.txt
  26  create mode 100644 Documentation/hwmon/rpi-poe-fan
  27
  28 --- /dev/null
  29 +++ b/Documentation/devicetree/bindings/hwmon/rpi-poe-fan.txt
  30 @@ -0,0 +1,55 @@
  31 +Bindings for the Raspberry Pi PoE HAT fan
  32 +
  33 +Required properties:
  34 +- compatible   : "raspberrypi,rpi-poe-fan"
  35 +- firmware     : Reference to the RPi firmware device node
  36 +- pwms         : the PWM that is used to control the PWM fan
  37 +- cooling-levels      : PWM duty cycle values in a range from 0 to 255
  38 +                       which correspond to thermal cooling states
  39 +
  40 +Example:
  41 +       fan0: rpi-poe-fan@0 {
  42 +               compatible = "raspberrypi,rpi-poe-fan";
  43 +               firmware = <&firmware>;
  44 +               cooling-min-state = <0>;
  45 +               cooling-max-state = <3>;
  46 +               #cooling-cells = <2>;
  47 +               cooling-levels = <0 50 150 255>;
  48 +               status = "okay";
  49 +       };
  50 +
  51 +       thermal-zones {
  52 +               cpu_thermal: cpu-thermal {
  53 +                       trips {
  54 +                               threshold: trip-point@0 {
  55 +                                       temperature = <45000>;
  56 +                                       hysteresis = <5000>;
  57 +                                       type = "active";
  58 +                               };
  59 +                               target: trip-point@1 {
  60 +                                       temperature = <50000>;
  61 +                                       hysteresis = <2000>;
  62 +                                       type = "active";
  63 +                               };
  64 +                               cpu_hot: cpu_hot@0 {
  65 +                                       temperature = <55000>;
  66 +                                       hysteresis = <2000>;
  67 +                                       type = "active";
  68 +                               };
  69 +                       };
  70 +                       cooling-maps {
  71 +                               map0 {
  72 +                                       trip = <&threshold>;
  73 +                                       cooling-device = <&fan0 0 1>;
  74 +                               };
  75 +                               map1 {
  76 +                                       trip = <&target>;
  77 +                                       cooling-device = <&fan0 1 2>;
  78 +                               };
  79 +                               map2 {
  80 +                                       trip = <&cpu_hot>;
  81 +                                       cooling-device = <&fan0 2 3>;
  82 +                               };
  83 +                       };
  84 +               };
  85 +       };
  86 --- /dev/null
  87 +++ b/Documentation/hwmon/rpi-poe-fan
  88 @@ -0,0 +1,15 @@
  89 +Kernel driver rpi-poe-fan
  90 +=====================
  91 +
  92 +This driver enables the use of the Raspberry Pi PoE HAT fan.
  93 +
  94 +Author: Serge Schneider <serge@raspberrypi.org>
  95 +
  96 +Description
  97 +-----------
  98 +
  99 +The driver implements a simple interface for driving the Raspberry Pi PoE
 100 +(Power over Ethernet) HAT fan. The driver passes commands to the Raspberry Pi
 101 +firmware through the mailbox property interface. The firmware then forwards
 102 +the commands to the board over I2C on the ID_EEPROM pins. The driver exposes
 103 +the fan to the user space through the hwmon sysfs interface.
 104 --- a/arch/arm/boot/dts/overlays/rpi-poe-overlay.dts
 105 +++ b/arch/arm/boot/dts/overlays/rpi-poe-overlay.dts
 106 @@ -11,7 +11,7 @@
 107                 target-path = "/";
 108                 __overlay__ {
 109                         fan0: rpi-poe-fan@0 {
 110 -                               compatible = "rpi-poe-fan";
 111 +                               compatible = "raspberrypi,rpi-poe-fan";
 112                                 firmware = <&firmware>;
 113                                 cooling-min-state = <0>;
 114                                 cooling-max-state = <3>;
 115 --- a/drivers/hwmon/Kconfig
 116 +++ b/drivers/hwmon/Kconfig
 117 @@ -1287,11 +1287,12 @@ config SENSORS_PWM_FAN
 118           will be called pwm-fan.
 119
 120  config SENSORS_RPI_POE_FAN
 121 -       tristate "Raspberry Pi POE HAT fan"
 122 +       tristate "Raspberry Pi PoE HAT fan"
 123         depends on RASPBERRYPI_FIRMWARE
 124         depends on THERMAL || THERMAL=n
 125         help
 126 -         If you say yes here you get support for Raspberry Pi POE HAT fan.
 127 +         If you say yes here you get support for Raspberry Pi PoE (Power over
 128 +         Ethernet) HAT fan.
 129
 130           This driver can also be built as a module.  If so, the module
 131           will be called rpi-poe-fan.
 132 --- a/drivers/hwmon/rpi-poe-fan.c
 133 +++ b/drivers/hwmon/rpi-poe-fan.c
 134 @@ -1,20 +1,11 @@
 135 +// SPDX-License-Identifier: GPL-2.0
 136  /*
 137 - * rpi-poe-fan.c - Hwmon driver for Raspberry Pi POE HAT fan.
 138 + * rpi-poe-fan.c - Hwmon driver for Raspberry Pi PoE HAT fan.
 139   *
 140   * Copyright (C) 2018 Raspberry Pi (Trading) Ltd.
 141   * Based on pwm-fan.c by Kamil Debski <k.debski@samsung.com>
 142   *
 143   * Author: Serge Schneider <serge@raspberrypi.org>
 144 - *
 145 - * This program is free software; you can redistribute it and/or modify
 146 - * it under the terms of the GNU General Public License as published by
 147 - * the Free Software Foundation; either version 2 of the License, or
 148 - * (at your option) any later version.
 149 - *
 150 - * This program is distributed in the hope that it will be useful,
 151 - * but WITHOUT ANY WARRANTY; without even the implied warranty of
 152 - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 153 - * GNU General Public License for more details.
 154   */
 155
 156  #include <linux/hwmon.h>
 157 @@ -46,41 +37,41 @@ struct rpi_poe_fan_ctx {
 158         struct notifier_block nb;
 159  };
 160
 161 -struct m_data_s{
 162 +struct fw_tag_data_s{
 163         u32 reg;
 164         u32 val;
 165         u32 ret;
 166  };
 167
 168  static int write_reg(struct rpi_firmware *fw, u32 reg, u32 *val){
 169 -       struct m_data_s m_data = {
 170 +       struct fw_tag_data_s fw_tag_data = {
 171                 .reg = reg,
 172                 .val = *val
 173         };
 174         int ret;
 175         ret = rpi_firmware_property(fw, RPI_FIRMWARE_SET_POE_HAT_VAL,
 176 -                                   &m_data, sizeof(m_data));
 177 +                                   &fw_tag_data, sizeof(fw_tag_data));
 178         if (ret) {
 179                 return ret;
 180 -       } else if (m_data.ret) {
 181 +       } else if (fw_tag_data.ret) {
 182                 return -EIO;
 183         }
 184         return 0;
 185  }
 186
 187  static int read_reg(struct rpi_firmware *fw, u32 reg, u32 *val){
 188 -       struct m_data_s m_data = {
 189 +       struct fw_tag_data_s fw_tag_data = {
 190                 .reg = reg,
 191         };
 192         int ret;
 193         ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_POE_HAT_VAL,
 194 -                                   &m_data, sizeof(m_data));
 195 +                                   &fw_tag_data, sizeof(fw_tag_data));
 196         if (ret) {
 197                 return ret;
 198 -       } else if (m_data.ret) {
 199 +       } else if (fw_tag_data.ret) {
 200                 return -EIO;
 201         }
 202 -       *val = m_data.val;
 203 +       *val = fw_tag_data.val;
 204         return 0;
 205  }
 206
 207 @@ -268,7 +259,8 @@ static int rpi_poe_fan_of_get_cooling_da
 208
 209         ret = of_property_count_u32_elems(np, "cooling-levels");
 210         if (ret <= 0) {
 211 -               dev_err(dev, "Wrong data!\n");
 212 +               dev_err(dev, "cooling-levels property missing or invalid: %d\n",
 213 +                       ret);
 214                 return ret ? : -EINVAL;
 215         }
 216
 217 @@ -397,10 +389,11 @@ static int rpi_poe_fan_suspend(struct de
 218  {
 219         struct rpi_poe_fan_ctx *ctx = dev_get_drvdata(dev);
 220         u32 value = 0;
 221 +       int ret = 0;
 222
 223         if (ctx->pwm_value != value)
 224                 ret = write_reg(ctx->fw, POE_CUR_PWM, &value);
 225 -       return 0;
 226 +       return ret;
 227  }
 228
 229  static int rpi_poe_fan_resume(struct device *dev)
 230 @@ -420,7 +413,7 @@ static SIMPLE_DEV_PM_OPS(rpi_poe_fan_pm,
 231                          rpi_poe_fan_resume);
 232
 233  static const struct of_device_id of_rpi_poe_fan_match[] = {
 234 -       { .compatible = "rpi-poe-fan", },
 235 +       { .compatible = "raspberrypi,rpi-poe-fan", },
 236         {},
 237  };
 238  MODULE_DEVICE_TABLE(of, of_rpi_poe_fan_match);
 239 @@ -439,5 +432,5 @@ module_platform_driver(rpi_poe_fan_drive
 240
 241  MODULE_AUTHOR("Serge Schneider <serge@raspberrypi.org>");
 242  MODULE_ALIAS("platform:rpi-poe-fan");
 243 -MODULE_DESCRIPTION("Raspberry Pi POE HAT fan driver");
 244 +MODULE_DESCRIPTION("Raspberry Pi PoE HAT fan driver");
 245  MODULE_LICENSE("GPL");