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-rw-r--r--target/linux/brcm2708/patches-4.19/950-0138-Add-rpi-poe-fan-driver.patch704
1 files changed, 704 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.19/950-0138-Add-rpi-poe-fan-driver.patch b/target/linux/brcm2708/patches-4.19/950-0138-Add-rpi-poe-fan-driver.patch
new file mode 100644
index 0000000000..659a2b4e06
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0138-Add-rpi-poe-fan-driver.patch
@@ -0,0 +1,704 @@
+From ae762f7cc705c20c8320613425a7179c3e6f47f3 Mon Sep 17 00:00:00 2001
+From: Serge Schneider <serge@raspberrypi.org>
+Date: Mon, 9 Jul 2018 12:54:25 +0100
+Subject: [PATCH 138/703] Add rpi-poe-fan driver
+
+Signed-off-by: Serge Schneider <serge@raspberrypi.org>
+
+PoE HAT driver cleanup
+
+* Fix undeclared variable in rpi_poe_fan_suspend
+* Add SPDX-License-Identifier
+* Expand PoE acronym in Kconfig help
+* Give clearer error message on of_property_count_u32_elems fail
+* Add documentation
+* Add vendor to of_device_id compatible string.
+* Rename m_data_s struct to fw_data_s
+* Fix typos
+
+Fixes: #2665
+
+Signed-off-by: Serge Schneider <serge@raspberrypi.org>
+---
+ .../devicetree/bindings/hwmon/rpi-poe-fan.txt | 55 +++
+ Documentation/hwmon/rpi-poe-fan | 15 +
+ arch/arm/boot/dts/overlays/Makefile | 1 +
+ arch/arm/boot/dts/overlays/README | 6 +
+ .../arm/boot/dts/overlays/rpi-poe-overlay.dts | 61 +++
+ arch/arm/configs/bcm2709_defconfig | 1 +
+ arch/arm/configs/bcmrpi_defconfig | 1 +
+ drivers/hwmon/Kconfig | 11 +
+ drivers/hwmon/Makefile | 1 +
+ drivers/hwmon/rpi-poe-fan.c | 436 ++++++++++++++++++
+ include/soc/bcm2835/raspberrypi-firmware.h | 2 +
+ 11 files changed, 590 insertions(+)
+ create mode 100644 Documentation/devicetree/bindings/hwmon/rpi-poe-fan.txt
+ create mode 100644 Documentation/hwmon/rpi-poe-fan
+ create mode 100644 arch/arm/boot/dts/overlays/rpi-poe-overlay.dts
+ create mode 100644 drivers/hwmon/rpi-poe-fan.c
+
+--- /dev/null
++++ b/Documentation/devicetree/bindings/hwmon/rpi-poe-fan.txt
+@@ -0,0 +1,55 @@
++Bindings for the Raspberry Pi PoE HAT fan
++
++Required properties:
++- compatible : "raspberrypi,rpi-poe-fan"
++- firmware : Reference to the RPi firmware device node
++- pwms : the PWM that is used to control the PWM fan
++- cooling-levels : PWM duty cycle values in a range from 0 to 255
++ which correspond to thermal cooling states
++
++Example:
++ fan0: rpi-poe-fan@0 {
++ compatible = "raspberrypi,rpi-poe-fan";
++ firmware = <&firmware>;
++ cooling-min-state = <0>;
++ cooling-max-state = <3>;
++ #cooling-cells = <2>;
++ cooling-levels = <0 50 150 255>;
++ status = "okay";
++ };
++
++ thermal-zones {
++ cpu_thermal: cpu-thermal {
++ trips {
++ threshold: trip-point@0 {
++ temperature = <45000>;
++ hysteresis = <5000>;
++ type = "active";
++ };
++ target: trip-point@1 {
++ temperature = <50000>;
++ hysteresis = <2000>;
++ type = "active";
++ };
++ cpu_hot: cpu_hot@0 {
++ temperature = <55000>;
++ hysteresis = <2000>;
++ type = "active";
++ };
++ };
++ cooling-maps {
++ map0 {
++ trip = <&threshold>;
++ cooling-device = <&fan0 0 1>;
++ };
++ map1 {
++ trip = <&target>;
++ cooling-device = <&fan0 1 2>;
++ };
++ map2 {
++ trip = <&cpu_hot>;
++ cooling-device = <&fan0 2 3>;
++ };
++ };
++ };
++ };
+--- /dev/null
++++ b/Documentation/hwmon/rpi-poe-fan
+@@ -0,0 +1,15 @@
++Kernel driver rpi-poe-fan
++=====================
++
++This driver enables the use of the Raspberry Pi PoE HAT fan.
++
++Author: Serge Schneider <serge@raspberrypi.org>
++
++Description
++-----------
++
++The driver implements a simple interface for driving the Raspberry Pi PoE
++(Power over Ethernet) HAT fan. The driver passes commands to the Raspberry Pi
++firmware through the mailbox property interface. The firmware then forwards
++the commands to the board over I2C on the ID_EEPROM pins. The driver exposes
++the fan to the user space through the hwmon sysfs interface.
+--- a/arch/arm/boot/dts/overlays/Makefile
++++ b/arch/arm/boot/dts/overlays/Makefile
+@@ -100,6 +100,7 @@ dtbo-$(CONFIG_ARCH_BCM2835) += \
+ rpi-dac.dtbo \
+ rpi-display.dtbo \
+ rpi-ft5406.dtbo \
++ rpi-poe.dtbo \
+ rpi-proto.dtbo \
+ rpi-sense.dtbo \
+ rpi-tv.dtbo \
+--- a/arch/arm/boot/dts/overlays/README
++++ b/arch/arm/boot/dts/overlays/README
+@@ -1515,6 +1515,12 @@ Params: touchscreen-size-x Touchscr
+ touchscreen-swapped-x-y Swap X and Y cordinates (default 0);
+
+
++Name: rpi-poe
++Info: Raspberry Pi POE HAT
++Load: dtoverlay=rpi-poe
++Params: <None>
++
++
+ Name: rpi-proto
+ Info: Configures the RPi Proto audio card
+ Load: dtoverlay=rpi-proto
+--- /dev/null
++++ b/arch/arm/boot/dts/overlays/rpi-poe-overlay.dts
+@@ -0,0 +1,61 @@
++/*
++ * Overlay for the Raspberry Pi POE HAT.
++ */
++/dts-v1/;
++/plugin/;
++
++/ {
++ compatible = "brcm,bcm2708";
++
++ fragment@0 {
++ target-path = "/";
++ __overlay__ {
++ fan0: rpi-poe-fan@0 {
++ compatible = "raspberrypi,rpi-poe-fan";
++ firmware = <&firmware>;
++ cooling-min-state = <0>;
++ cooling-max-state = <3>;
++ #cooling-cells = <2>;
++ cooling-levels = <0 50 150 255>;
++ status = "okay";
++ };
++ };
++ };
++
++ fragment@1 {
++ target = <&cpu_thermal>;
++ __overlay__ {
++ trips {
++ threshold: trip-point@0 {
++ temperature = <45000>;
++ hysteresis = <5000>;
++ type = "active";
++ };
++ target: trip-point@1 {
++ temperature = <50000>;
++ hysteresis = <2000>;
++ type = "active";
++ };
++ cpu_hot: cpu_hot@0 {
++ temperature = <55000>;
++ hysteresis = <2000>;
++ type = "active";
++ };
++ };
++ cooling-maps {
++ map0 {
++ trip = <&threshold>;
++ cooling-device = <&fan0 0 1>;
++ };
++ map1 {
++ trip = <&target>;
++ cooling-device = <&fan0 1 2>;
++ };
++ map2 {
++ trip = <&cpu_hot>;
++ cooling-device = <&fan0 2 3>;
++ };
++ };
++ };
++ };
++};
+--- a/arch/arm/configs/bcm2709_defconfig
++++ b/arch/arm/configs/bcm2709_defconfig
+@@ -659,6 +659,7 @@ CONFIG_HWMON=m
+ CONFIG_SENSORS_DS1621=m
+ CONFIG_SENSORS_JC42=m
+ CONFIG_SENSORS_LM75=m
++CONFIG_SENSORS_RPI_POE_FAN=m
+ CONFIG_SENSORS_SHT21=m
+ CONFIG_SENSORS_SHT3x=m
+ CONFIG_SENSORS_SHTC1=m
+--- a/arch/arm/configs/bcmrpi_defconfig
++++ b/arch/arm/configs/bcmrpi_defconfig
+@@ -652,6 +652,7 @@ CONFIG_HWMON=m
+ CONFIG_SENSORS_DS1621=m
+ CONFIG_SENSORS_JC42=m
+ CONFIG_SENSORS_LM75=m
++CONFIG_SENSORS_RPI_POE_FAN=m
+ CONFIG_SENSORS_SHT21=m
+ CONFIG_SENSORS_SHT3x=m
+ CONFIG_SENSORS_SHTC1=m
+--- a/drivers/hwmon/Kconfig
++++ b/drivers/hwmon/Kconfig
+@@ -1330,6 +1330,17 @@ config SENSORS_RASPBERRYPI_HWMON
+ This driver can also be built as a module. If so, the module
+ will be called raspberrypi-hwmon.
+
++config SENSORS_RPI_POE_FAN
++ tristate "Raspberry Pi PoE HAT fan"
++ depends on RASPBERRYPI_FIRMWARE
++ depends on THERMAL || THERMAL=n
++ help
++ If you say yes here you get support for Raspberry Pi PoE (Power over
++ Ethernet) HAT fan.
++
++ This driver can also be built as a module. If so, the module
++ will be called rpi-poe-fan.
++
+ config SENSORS_SHT15
+ tristate "Sensiron humidity and temperature sensors. SHT15 and compat."
+ depends on GPIOLIB || COMPILE_TEST
+--- a/drivers/hwmon/Makefile
++++ b/drivers/hwmon/Makefile
+@@ -144,6 +144,7 @@ obj-$(CONFIG_SENSORS_PCF8591) += pcf8591
+ obj-$(CONFIG_SENSORS_POWR1220) += powr1220.o
+ obj-$(CONFIG_SENSORS_PWM_FAN) += pwm-fan.o
+ obj-$(CONFIG_SENSORS_RASPBERRYPI_HWMON) += raspberrypi-hwmon.o
++obj-$(CONFIG_SENSORS_RPI_POE_FAN) += rpi-poe-fan.o
+ obj-$(CONFIG_SENSORS_S3C) += s3c-hwmon.o
+ obj-$(CONFIG_SENSORS_SCH56XX_COMMON)+= sch56xx-common.o
+ obj-$(CONFIG_SENSORS_SCH5627) += sch5627.o
+--- /dev/null
++++ b/drivers/hwmon/rpi-poe-fan.c
+@@ -0,0 +1,436 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * rpi-poe-fan.c - Hwmon driver for Raspberry Pi PoE HAT fan.
++ *
++ * Copyright (C) 2018 Raspberry Pi (Trading) Ltd.
++ * Based on pwm-fan.c by Kamil Debski <k.debski@samsung.com>
++ *
++ * Author: Serge Schneider <serge@raspberrypi.org>
++ */
++
++#include <linux/hwmon.h>
++#include <linux/hwmon-sysfs.h>
++#include <linux/module.h>
++#include <linux/mutex.h>
++#include <linux/notifier.h>
++#include <linux/of.h>
++#include <linux/platform_device.h>
++#include <linux/reboot.h>
++#include <linux/sysfs.h>
++#include <linux/thermal.h>
++#include <soc/bcm2835/raspberrypi-firmware.h>
++
++#define MAX_PWM 255
++
++#define POE_CUR_PWM 0x0
++#define POE_DEF_PWM 0x1
++
++struct rpi_poe_fan_ctx {
++ struct mutex lock;
++ struct rpi_firmware *fw;
++ unsigned int pwm_value;
++ unsigned int def_pwm_value;
++ unsigned int rpi_poe_fan_state;
++ unsigned int rpi_poe_fan_max_state;
++ unsigned int *rpi_poe_fan_cooling_levels;
++ struct thermal_cooling_device *cdev;
++ struct notifier_block nb;
++};
++
++struct fw_tag_data_s{
++ u32 reg;
++ u32 val;
++ u32 ret;
++};
++
++static int write_reg(struct rpi_firmware *fw, u32 reg, u32 *val){
++ struct fw_tag_data_s fw_tag_data = {
++ .reg = reg,
++ .val = *val
++ };
++ int ret;
++ ret = rpi_firmware_property(fw, RPI_FIRMWARE_SET_POE_HAT_VAL,
++ &fw_tag_data, sizeof(fw_tag_data));
++ if (ret) {
++ return ret;
++ } else if (fw_tag_data.ret) {
++ return -EIO;
++ }
++ return 0;
++}
++
++static int read_reg(struct rpi_firmware *fw, u32 reg, u32 *val){
++ struct fw_tag_data_s fw_tag_data = {
++ .reg = reg,
++ };
++ int ret;
++ ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_POE_HAT_VAL,
++ &fw_tag_data, sizeof(fw_tag_data));
++ if (ret) {
++ return ret;
++ } else if (fw_tag_data.ret) {
++ return -EIO;
++ }
++ *val = fw_tag_data.val;
++ return 0;
++}
++
++static int rpi_poe_reboot(struct notifier_block *nb, unsigned long code,
++ void *unused)
++{
++ struct rpi_poe_fan_ctx *ctx = container_of(nb, struct rpi_poe_fan_ctx,
++ nb);
++
++ if (ctx->pwm_value != ctx->def_pwm_value)
++ write_reg(ctx->fw, POE_CUR_PWM, &ctx->def_pwm_value);
++
++ return NOTIFY_DONE;
++}
++
++static int __set_pwm(struct rpi_poe_fan_ctx *ctx, u32 pwm)
++{
++ int ret = 0;
++
++ mutex_lock(&ctx->lock);
++ if (ctx->pwm_value == pwm)
++ goto exit_set_pwm_err;
++
++ ret = write_reg(ctx->fw, POE_CUR_PWM, &pwm);
++ if (!ret)
++ ctx->pwm_value = pwm;
++exit_set_pwm_err:
++ mutex_unlock(&ctx->lock);
++ return ret;
++}
++
++static int __set_def_pwm(struct rpi_poe_fan_ctx *ctx, u32 def_pwm)
++{
++ int ret = 0;
++ mutex_lock(&ctx->lock);
++ if (ctx->def_pwm_value == def_pwm)
++ goto exit_set_def_pwm_err;
++
++ ret = write_reg(ctx->fw, POE_CUR_PWM, &def_pwm);
++ if (!ret)
++ ctx->def_pwm_value = def_pwm;
++exit_set_def_pwm_err:
++ mutex_unlock(&ctx->lock);
++ return ret;
++}
++
++static void rpi_poe_fan_update_state(struct rpi_poe_fan_ctx *ctx,
++ unsigned long pwm)
++{
++ int i;
++
++ for (i = 0; i < ctx->rpi_poe_fan_max_state; ++i)
++ if (pwm < ctx->rpi_poe_fan_cooling_levels[i + 1])
++ break;
++
++ ctx->rpi_poe_fan_state = i;
++}
++
++static ssize_t set_pwm(struct device *dev, struct device_attribute *attr,
++ const char *buf, size_t count)
++{
++ struct rpi_poe_fan_ctx *ctx = dev_get_drvdata(dev);
++ unsigned long pwm;
++ int ret;
++
++ if (kstrtoul(buf, 10, &pwm) || pwm > MAX_PWM)
++ return -EINVAL;
++
++ ret = __set_pwm(ctx, pwm);
++ if (ret)
++ return ret;
++
++ rpi_poe_fan_update_state(ctx, pwm);
++ return count;
++}
++
++static ssize_t set_def_pwm(struct device *dev, struct device_attribute *attr,
++ const char *buf, size_t count)
++{
++ struct rpi_poe_fan_ctx *ctx = dev_get_drvdata(dev);
++ unsigned long def_pwm;
++ int ret;
++
++ if (kstrtoul(buf, 10, &def_pwm) || def_pwm > MAX_PWM)
++ return -EINVAL;
++
++ ret = __set_def_pwm(ctx, def_pwm);
++ if (ret)
++ return ret;
++ return count;
++}
++
++static ssize_t show_pwm(struct device *dev,
++ struct device_attribute *attr, char *buf)
++{
++ struct rpi_poe_fan_ctx *ctx = dev_get_drvdata(dev);
++
++ return sprintf(buf, "%u\n", ctx->pwm_value);
++}
++
++static ssize_t show_def_pwm(struct device *dev,
++ struct device_attribute *attr, char *buf)
++{
++ struct rpi_poe_fan_ctx *ctx = dev_get_drvdata(dev);
++
++ return sprintf(buf, "%u\n", ctx->def_pwm_value);
++}
++
++
++static SENSOR_DEVICE_ATTR(pwm1, 0644, show_pwm, set_pwm, 0);
++static SENSOR_DEVICE_ATTR(def_pwm1, 0644, show_def_pwm, set_def_pwm, 1);
++
++static struct attribute *rpi_poe_fan_attrs[] = {
++ &sensor_dev_attr_pwm1.dev_attr.attr,
++ &sensor_dev_attr_def_pwm1.dev_attr.attr,
++ NULL,
++};
++
++ATTRIBUTE_GROUPS(rpi_poe_fan);
++
++/* thermal cooling device callbacks */
++static int rpi_poe_fan_get_max_state(struct thermal_cooling_device *cdev,
++ unsigned long *state)
++{
++ struct rpi_poe_fan_ctx *ctx = cdev->devdata;
++
++ if (!ctx)
++ return -EINVAL;
++
++ *state = ctx->rpi_poe_fan_max_state;
++
++ return 0;
++}
++
++static int rpi_poe_fan_get_cur_state(struct thermal_cooling_device *cdev,
++ unsigned long *state)
++{
++ struct rpi_poe_fan_ctx *ctx = cdev->devdata;
++
++ if (!ctx)
++ return -EINVAL;
++
++ *state = ctx->rpi_poe_fan_state;
++
++ return 0;
++}
++
++static int rpi_poe_fan_set_cur_state(struct thermal_cooling_device *cdev,
++ unsigned long state)
++{
++ struct rpi_poe_fan_ctx *ctx = cdev->devdata;
++ int ret;
++
++ if (!ctx || (state > ctx->rpi_poe_fan_max_state))
++ return -EINVAL;
++
++ if (state == ctx->rpi_poe_fan_state)
++ return 0;
++
++ ret = __set_pwm(ctx, ctx->rpi_poe_fan_cooling_levels[state]);
++ if (ret) {
++ dev_err(&cdev->device, "Cannot set pwm!\n");
++ return ret;
++ }
++
++ ctx->rpi_poe_fan_state = state;
++
++ return ret;
++}
++
++static const struct thermal_cooling_device_ops rpi_poe_fan_cooling_ops = {
++ .get_max_state = rpi_poe_fan_get_max_state,
++ .get_cur_state = rpi_poe_fan_get_cur_state,
++ .set_cur_state = rpi_poe_fan_set_cur_state,
++};
++
++static int rpi_poe_fan_of_get_cooling_data(struct device *dev,
++ struct rpi_poe_fan_ctx *ctx)
++{
++ struct device_node *np = dev->of_node;
++ int num, i, ret;
++
++ if (!of_find_property(np, "cooling-levels", NULL))
++ return 0;
++
++ ret = of_property_count_u32_elems(np, "cooling-levels");
++ if (ret <= 0) {
++ dev_err(dev, "cooling-levels property missing or invalid: %d\n",
++ ret);
++ return ret ? : -EINVAL;
++ }
++
++ num = ret;
++ ctx->rpi_poe_fan_cooling_levels = devm_kzalloc(dev, num * sizeof(u32),
++ GFP_KERNEL);
++ if (!ctx->rpi_poe_fan_cooling_levels)
++ return -ENOMEM;
++
++ ret = of_property_read_u32_array(np, "cooling-levels",
++ ctx->rpi_poe_fan_cooling_levels, num);
++ if (ret) {
++ dev_err(dev, "Property 'cooling-levels' cannot be read!\n");
++ return ret;
++ }
++
++ for (i = 0; i < num; i++) {
++ if (ctx->rpi_poe_fan_cooling_levels[i] > MAX_PWM) {
++ dev_err(dev, "PWM fan state[%d]:%d > %d\n", i,
++ ctx->rpi_poe_fan_cooling_levels[i], MAX_PWM);
++ return -EINVAL;
++ }
++ }
++
++ ctx->rpi_poe_fan_max_state = num - 1;
++
++ return 0;
++}
++
++static int rpi_poe_fan_probe(struct platform_device *pdev)
++{
++ struct thermal_cooling_device *cdev;
++ struct rpi_poe_fan_ctx *ctx;
++ struct device *hwmon;
++ struct device_node *np = pdev->dev.of_node;
++ struct device_node *fw_node;
++ int ret;
++
++ fw_node = of_parse_phandle(np, "firmware", 0);
++ if (!fw_node) {
++ dev_err(&pdev->dev, "Missing firmware node\n");
++ return -ENOENT;
++ }
++
++ ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
++ if (!ctx)
++ return -ENOMEM;
++
++ mutex_init(&ctx->lock);
++
++ ctx->fw = rpi_firmware_get(fw_node);
++ if (!ctx->fw)
++ return -EPROBE_DEFER;
++
++ platform_set_drvdata(pdev, ctx);
++
++ ctx->nb.notifier_call = rpi_poe_reboot;
++ ret = register_reboot_notifier(&ctx->nb);
++ if (ret) {
++ dev_err(&pdev->dev, "Failed to register reboot notifier: %i\n",
++ ret);
++ return ret;
++ }
++ ret = read_reg(ctx->fw, POE_DEF_PWM, &ctx->def_pwm_value);
++ if (ret) {
++ dev_err(&pdev->dev, "Failed to get default PWM value: %i\n",
++ ret);
++ goto err;
++ }
++ ret = read_reg(ctx->fw, POE_CUR_PWM, &ctx->pwm_value);
++ if (ret) {
++ dev_err(&pdev->dev, "Failed to get current PWM value: %i\n",
++ ret);
++ goto err;
++ }
++
++ hwmon = devm_hwmon_device_register_with_groups(&pdev->dev, "rpipoefan",
++ ctx, rpi_poe_fan_groups);
++ if (IS_ERR(hwmon)) {
++ dev_err(&pdev->dev, "Failed to register hwmon device\n");
++ ret = PTR_ERR(hwmon);
++ goto err;
++ }
++
++ ret = rpi_poe_fan_of_get_cooling_data(&pdev->dev, ctx);
++ if (ret)
++ return ret;
++
++ rpi_poe_fan_update_state(ctx, ctx->pwm_value);
++ if (!IS_ENABLED(CONFIG_THERMAL))
++ return 0;
++
++ cdev = thermal_of_cooling_device_register(np,
++ "rpi-poe-fan", ctx,
++ &rpi_poe_fan_cooling_ops);
++ if (IS_ERR(cdev)) {
++ dev_err(&pdev->dev,
++ "Failed to register rpi-poe-fan as cooling device");
++ ret = PTR_ERR(cdev);
++ goto err;
++ }
++ ctx->cdev = cdev;
++ thermal_cdev_update(cdev);
++
++ return 0;
++err:
++ unregister_reboot_notifier(&ctx->nb);
++ return ret;
++}
++
++static int rpi_poe_fan_remove(struct platform_device *pdev)
++{
++ struct rpi_poe_fan_ctx *ctx = platform_get_drvdata(pdev);
++ u32 value = ctx->def_pwm_value;
++
++ unregister_reboot_notifier(&ctx->nb);
++ thermal_cooling_device_unregister(ctx->cdev);
++ if (ctx->pwm_value != value) {
++ write_reg(ctx->fw, POE_CUR_PWM, &value);
++ }
++ return 0;
++}
++
++#ifdef CONFIG_PM_SLEEP
++static int rpi_poe_fan_suspend(struct device *dev)
++{
++ struct rpi_poe_fan_ctx *ctx = dev_get_drvdata(dev);
++ u32 value = 0;
++ int ret = 0;
++
++ if (ctx->pwm_value != value)
++ ret = write_reg(ctx->fw, POE_CUR_PWM, &value);
++ return ret;
++}
++
++static int rpi_poe_fan_resume(struct device *dev)
++{
++ struct rpi_poe_fan_ctx *ctx = dev_get_drvdata(dev);
++ u32 value = ctx->pwm_value;
++ int ret = 0;
++
++ if (value != 0)
++ ret = write_reg(ctx->fw, POE_CUR_PWM, &value);
++
++ return ret;
++}
++#endif
++
++static SIMPLE_DEV_PM_OPS(rpi_poe_fan_pm, rpi_poe_fan_suspend,
++ rpi_poe_fan_resume);
++
++static const struct of_device_id of_rpi_poe_fan_match[] = {
++ { .compatible = "raspberrypi,rpi-poe-fan", },
++ {},
++};
++MODULE_DEVICE_TABLE(of, of_rpi_poe_fan_match);
++
++static struct platform_driver rpi_poe_fan_driver = {
++ .probe = rpi_poe_fan_probe,
++ .remove = rpi_poe_fan_remove,
++ .driver = {
++ .name = "rpi-poe-fan",
++ .pm = &rpi_poe_fan_pm,
++ .of_match_table = of_rpi_poe_fan_match,
++ },
++};
++
++module_platform_driver(rpi_poe_fan_driver);
++
++MODULE_AUTHOR("Serge Schneider <serge@raspberrypi.org>");
++MODULE_ALIAS("platform:rpi-poe-fan");
++MODULE_DESCRIPTION("Raspberry Pi PoE HAT fan driver");
++MODULE_LICENSE("GPL");
+--- a/include/soc/bcm2835/raspberrypi-firmware.h
++++ b/include/soc/bcm2835/raspberrypi-firmware.h
+@@ -93,6 +93,8 @@ enum rpi_firmware_property_tag {
+ RPI_FIRMWARE_SET_GPIO_CONFIG = 0x00038043,
+ RPI_FIRMWARE_GET_PERIPH_REG = 0x00030045,
+ RPI_FIRMWARE_SET_PERIPH_REG = 0x00038045,
++ RPI_FIRMWARE_GET_POE_HAT_VAL = 0x00030049,
++ RPI_FIRMWARE_SET_POE_HAT_VAL = 0x00030050,
+
+
+ /* Dispmanx TAGS */