diff mbox series

[v6,3/6] drivers: hwmon: Add the iEi WT61P803 PUZZLE HWMON driver

Message ID 20201019221859.56680-4-luka.kovacic@sartura.hr
State New
Headers show
Series Add support for the iEi WT61P803 PUZZLE MCU | expand

Commit Message

Luka Kovacic Oct. 19, 2020, 10:18 p.m. UTC
Add the iEi WT61P803 PUZZLE HWMON driver, that handles the fan speed
control via PWM, reading fan speed and reading on-board temperature
sensors.

The driver registers a HWMON device and a simple thermal cooling device to
enable in-kernel fan management.

This driver depends on the iEi WT61P803 PUZZLE MFD driver.

Signed-off-by: Luka Kovacic <luka.kovacic@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Cc: Robert Marko <robert.marko@sartura.hr>
---
 drivers/hwmon/Kconfig                     |   8 +
 drivers/hwmon/Makefile                    |   1 +
 drivers/hwmon/iei-wt61p803-puzzle-hwmon.c | 410 ++++++++++++++++++++++
 3 files changed, 419 insertions(+)
 create mode 100644 drivers/hwmon/iei-wt61p803-puzzle-hwmon.c

Comments

Andy Shevchenko Oct. 20, 2020, 9 a.m. UTC | #1
On Tue, Oct 20, 2020 at 1:19 AM Luka Kovacic <luka.kovacic@sartura.hr> wrote:
>

> Add the iEi WT61P803 PUZZLE HWMON driver, that handles the fan speed

> control via PWM, reading fan speed and reading on-board temperature

> sensors.

>

> The driver registers a HWMON device and a simple thermal cooling device to

> enable in-kernel fan management.

>

> This driver depends on the iEi WT61P803 PUZZLE MFD driver.


...

> +// SPDX-License-Identifier: GPL-2.0-only

> +/* iEi WT61P803 PUZZLE MCU HWMON Driver


Shouldn't be
/*
 * IEI ...

?

...

> +/**

> + * struct iei_wt61p803_puzzle_thermal_cooling_device - Thermal cooling device instance


> + *


Please, remove all these blank lines in kernel doc descriptions.

> + * @mcu_hwmon:         MCU HWMON struct pointer

> + * @tcdev:             Thermal cooling device pointer

> + * @name:              Thermal cooling device name

> + * @pwm_channel:       PWM channel (0 or 1)

> + * @cooling_levels:    Thermal cooling device cooling levels

> + */


...

> +struct iei_wt61p803_puzzle_hwmon {

> +       struct iei_wt61p803_puzzle *mcu;

> +       unsigned char *response_buffer;

> +       bool thermal_cooling_dev_present[IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM];

> +       struct iei_wt61p803_puzzle_thermal_cooling_device

> +               *cdev[IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM];


Isn't this constant a bit too long? Perhaps drop NUM (MAX would
suffice I think) for a starter.

> +};


...

> +       static unsigned char temp_sensor_ntc_cmd[4] = {

> +               IEI_WT61P803_PUZZLE_CMD_HEADER_START,

> +               IEI_WT61P803_PUZZLE_CMD_TEMP,

> +               IEI_WT61P803_PUZZLE_CMD_TEMP_ALL


+ comma.

> +       };


Why not to be consistent with the rest assignments, choose either
above form, or like you have done in the below functions.
Also, why 4?

> +       size_t reply_size = 0;


How is it used in all these functions?

> +       int ret;

> +

> +       ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, temp_sensor_ntc_cmd,

> +                                               sizeof(temp_sensor_ntc_cmd), resp_buf,

> +                                               &reply_size);

> +

> +       if (ret)

> +               return ret;

> +

> +       /* Check the number of NTC values (should be 0x32/'2') */


> +       if (resp_buf[3] != 0x32)


Instead of comment in the parentheses, just do it here
" != '2')"

> +               return -EIO;


...

> +static int iei_wt61p803_puzzle_read(struct device *dev, enum hwmon_sensor_types type,

> +                                   u32 attr, int channel, long *val)

> +{

> +       struct iei_wt61p803_puzzle_hwmon *mcu_hwmon = dev_get_drvdata(dev->parent);

> +       int ret;

> +

> +       switch (type) {

> +       case hwmon_pwm:


> +               ret = iei_wt61p803_puzzle_read_pwm_channel(mcu_hwmon, channel, val);

> +               return ret;


  return iei_...(...);
in all such cases.

> +       case hwmon_fan:

> +               ret = iei_wt61p803_puzzle_read_fan_speed(mcu_hwmon, channel, val);

> +               return ret;

> +       case hwmon_temp:

> +               ret = iei_wt61p803_puzzle_read_temp_sensor(mcu_hwmon, channel, val);

> +               return ret;

> +       default:

> +               return -EINVAL;

> +       }

> +}


...

> +static umode_t iei_wt61p803_puzzle_is_visible(const void *data, enum hwmon_sensor_types type,

> +                                             u32 attr, int channel)

> +{

> +       switch (type) {

> +       case hwmon_pwm:


> +               switch (attr) {

> +               case hwmon_pwm_input:

> +                       return 0644;

> +               default:

> +                       return 0;

> +               }


Isn't too long for
  if (attr == ...)
    return 0644;
  break;

...see below...

> +       case hwmon_fan:

> +               switch (attr) {

> +               case hwmon_fan_input:

> +                       return 0444;

> +               default:

> +                       return 0;

> +               }

> +       case hwmon_temp:

> +               switch (attr) {

> +               case hwmon_temp_input:

> +                       return 0444;

> +               default:

> +                       return 0;

> +               }


> +       default:

> +               return 0;


break;

> +       }


return 0;

?

> +}


...

> +       mcu_hwmon->thermal_cooling_dev_present[pwm_channel] = true;

> +


> +       num_levels = fwnode_property_read_u8_array(child, "cooling-levels", NULL, 0);


fwnode_property_count_u8()

> +       if (num_levels > 0) {


You can improve readability by reducing indentation level via
replacement to negative conditional.

> +               cdev = devm_kzalloc(dev, sizeof(*cdev), GFP_KERNEL);

> +               if (!cdev)

> +                       return -ENOMEM;

> +

> +               cdev->cooling_levels = devm_kzalloc(dev, num_levels, GFP_KERNEL);


For the sake of cleaness, shouldn't it be devm_kmalloc_array() ?
(Note, zeroing is not needed if you read entire array)

> +               if (!cdev->cooling_levels)

> +                       return -ENOMEM;

> +

> +               ret = fwnode_property_read_u8_array(child, "cooling-levels",

> +                                                   cdev->cooling_levels,

> +                                                   num_levels);

> +               if (ret) {

> +                       dev_err(dev, "Couldn't read property 'cooling-levels'");

> +                       return ret;

> +               }

> +

> +               snprintf(cdev->name, THERMAL_NAME_LENGTH, "iei_wt61p803_puzzle_%d", pwm_channel);

> +

> +               cdev->tcdev = devm_thermal_of_cooling_device_register(dev, NULL,

> +                               cdev->name, cdev, &iei_wt61p803_puzzle_cooling_ops);

> +               if (IS_ERR(cdev->tcdev))

> +                       return PTR_ERR(cdev->tcdev);

> +

> +               cdev->mcu_hwmon = mcu_hwmon;

> +               cdev->pwm_channel = pwm_channel;

> +

> +               mcu_hwmon->cdev[pwm_channel] = cdev;

> +       }

> +       return 0;

> +}


-- 
With Best Regards,
Andy Shevchenko
Luka Kovacic Oct. 23, 2020, 9:47 p.m. UTC | #2
Hi Andy,

On Tue, Oct 20, 2020 at 10:59 AM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>

> On Tue, Oct 20, 2020 at 1:19 AM Luka Kovacic <luka.kovacic@sartura.hr> wrote:

> >

> > Add the iEi WT61P803 PUZZLE HWMON driver, that handles the fan speed

> > control via PWM, reading fan speed and reading on-board temperature

> > sensors.

> >

> > The driver registers a HWMON device and a simple thermal cooling device to

> > enable in-kernel fan management.

> >

> > This driver depends on the iEi WT61P803 PUZZLE MFD driver.

>

> ...

>

> > +// SPDX-License-Identifier: GPL-2.0-only

> > +/* iEi WT61P803 PUZZLE MCU HWMON Driver

>

> Shouldn't be

> /*

>  * IEI ...

>

> ?

>

> ...

>

> > +/**

> > + * struct iei_wt61p803_puzzle_thermal_cooling_device - Thermal cooling device instance

>

> > + *

>

> Please, remove all these blank lines in kernel doc descriptions.

>

> > + * @mcu_hwmon:         MCU HWMON struct pointer

> > + * @tcdev:             Thermal cooling device pointer

> > + * @name:              Thermal cooling device name

> > + * @pwm_channel:       PWM channel (0 or 1)

> > + * @cooling_levels:    Thermal cooling device cooling levels

> > + */

>

> ...

>

> > +struct iei_wt61p803_puzzle_hwmon {

> > +       struct iei_wt61p803_puzzle *mcu;

> > +       unsigned char *response_buffer;

> > +       bool thermal_cooling_dev_present[IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM];

> > +       struct iei_wt61p803_puzzle_thermal_cooling_device

> > +               *cdev[IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM];

>

> Isn't this constant a bit too long? Perhaps drop NUM (MAX would

> suffice I think) for a starter.


Okay, I'll drop NUM.

>

> > +};

>

> ...

>

> > +       static unsigned char temp_sensor_ntc_cmd[4] = {

> > +               IEI_WT61P803_PUZZLE_CMD_HEADER_START,

> > +               IEI_WT61P803_PUZZLE_CMD_TEMP,

> > +               IEI_WT61P803_PUZZLE_CMD_TEMP_ALL

>

> + comma.

>

> > +       };

>

> Why not to be consistent with the rest assignments, choose either

> above form, or like you have done in the below functions.


Assignments, where the array content will not be modified with custom
values are done as above.
Although I could change these to the other form, if that makes it clearer.

> Also, why 4?


1 additional character is always required, as this array is passed by reference
to the iei_wt61p803_puzzle_write_command() function, which requires it to
store a calculated checksum of the array content.

This is done to avoid unnecessary copying of the array inside the MFD driver.

The checksum is a part of the command, so the driver and the MCU can check
the integrity of the sent data.

>

> > +       size_t reply_size = 0;

>

> How is it used in all these functions?


I will add an additional check for the size of the received reply, as
it should be fixed.

>

> > +       int ret;

> > +

> > +       ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, temp_sensor_ntc_cmd,

> > +                                               sizeof(temp_sensor_ntc_cmd), resp_buf,

> > +                                               &reply_size);

> > +

> > +       if (ret)

> > +               return ret;

> > +

> > +       /* Check the number of NTC values (should be 0x32/'2') */

>

> > +       if (resp_buf[3] != 0x32)

>

> Instead of comment in the parentheses, just do it here

> " != '2')"

>

> > +               return -EIO;

>

> ...

>

> > +static int iei_wt61p803_puzzle_read(struct device *dev, enum hwmon_sensor_types type,

> > +                                   u32 attr, int channel, long *val)

> > +{

> > +       struct iei_wt61p803_puzzle_hwmon *mcu_hwmon = dev_get_drvdata(dev->parent);

> > +       int ret;

> > +

> > +       switch (type) {

> > +       case hwmon_pwm:

>

> > +               ret = iei_wt61p803_puzzle_read_pwm_channel(mcu_hwmon, channel, val);

> > +               return ret;

>

>   return iei_...(...);

> in all such cases.

>

> > +       case hwmon_fan:

> > +               ret = iei_wt61p803_puzzle_read_fan_speed(mcu_hwmon, channel, val);

> > +               return ret;

> > +       case hwmon_temp:

> > +               ret = iei_wt61p803_puzzle_read_temp_sensor(mcu_hwmon, channel, val);

> > +               return ret;

> > +       default:

> > +               return -EINVAL;

> > +       }

> > +}

>

> ...

>

> > +static umode_t iei_wt61p803_puzzle_is_visible(const void *data, enum hwmon_sensor_types type,

> > +                                             u32 attr, int channel)

> > +{

> > +       switch (type) {

> > +       case hwmon_pwm:

>

> > +               switch (attr) {

> > +               case hwmon_pwm_input:

> > +                       return 0644;

> > +               default:

> > +                       return 0;

> > +               }

>

> Isn't too long for

>   if (attr == ...)

>     return 0644;

>   break;

>

> ...see below...

>

> > +       case hwmon_fan:

> > +               switch (attr) {

> > +               case hwmon_fan_input:

> > +                       return 0444;

> > +               default:

> > +                       return 0;

> > +               }

> > +       case hwmon_temp:

> > +               switch (attr) {

> > +               case hwmon_temp_input:

> > +                       return 0444;

> > +               default:

> > +                       return 0;

> > +               }

>

> > +       default:

> > +               return 0;

>

> break;

>

> > +       }

>

> return 0;

>

> ?

>

> > +}

>

> ...

>

> > +       mcu_hwmon->thermal_cooling_dev_present[pwm_channel] = true;

> > +

>

> > +       num_levels = fwnode_property_read_u8_array(child, "cooling-levels", NULL, 0);

>

> fwnode_property_count_u8()

>

> > +       if (num_levels > 0) {

>

> You can improve readability by reducing indentation level via

> replacement to negative conditional.

>

> > +               cdev = devm_kzalloc(dev, sizeof(*cdev), GFP_KERNEL);

> > +               if (!cdev)

> > +                       return -ENOMEM;

> > +

> > +               cdev->cooling_levels = devm_kzalloc(dev, num_levels, GFP_KERNEL);

>

> For the sake of cleaness, shouldn't it be devm_kmalloc_array() ?

> (Note, zeroing is not needed if you read entire array)


I agree, this can be converted to devm_kmalloc_array().

>

> > +               if (!cdev->cooling_levels)

> > +                       return -ENOMEM;

> > +

> > +               ret = fwnode_property_read_u8_array(child, "cooling-levels",

> > +                                                   cdev->cooling_levels,

> > +                                                   num_levels);

> > +               if (ret) {

> > +                       dev_err(dev, "Couldn't read property 'cooling-levels'");

> > +                       return ret;

> > +               }

> > +

> > +               snprintf(cdev->name, THERMAL_NAME_LENGTH, "iei_wt61p803_puzzle_%d", pwm_channel);

> > +

> > +               cdev->tcdev = devm_thermal_of_cooling_device_register(dev, NULL,

> > +                               cdev->name, cdev, &iei_wt61p803_puzzle_cooling_ops);

> > +               if (IS_ERR(cdev->tcdev))

> > +                       return PTR_ERR(cdev->tcdev);

> > +

> > +               cdev->mcu_hwmon = mcu_hwmon;

> > +               cdev->pwm_channel = pwm_channel;

> > +

> > +               mcu_hwmon->cdev[pwm_channel] = cdev;

> > +       }

> > +       return 0;

> > +}

>

> --

> With Best Regards,

> Andy Shevchenko


I'll fix the issues you have mentioned above in the next patchset.

Kind regards,
Luka
diff mbox series

Patch

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 8dc28b26916e..ff279df9bf40 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -722,6 +722,14 @@  config SENSORS_IBMPOWERNV
 	  This driver can also be built as a module. If so, the module
 	  will be called ibmpowernv.
 
+config SENSORS_IEI_WT61P803_PUZZLE_HWMON
+	tristate "iEi WT61P803 PUZZLE MFD HWMON Driver"
+	depends on MFD_IEI_WT61P803_PUZZLE
+	help
+	  The iEi WT61P803 PUZZLE MFD HWMON Driver handles reading fan speed
+	  and writing fan PWM values. It also supports reading on-board
+	  temperature sensors.
+
 config SENSORS_IIO_HWMON
 	tristate "Hwmon driver that uses channels specified via iio maps"
 	depends on IIO
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index a8f4b35b136b..b0afb2d6896f 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -83,6 +83,7 @@  obj-$(CONFIG_SENSORS_HIH6130)	+= hih6130.o
 obj-$(CONFIG_SENSORS_ULTRA45)	+= ultra45_env.o
 obj-$(CONFIG_SENSORS_I5500)	+= i5500_temp.o
 obj-$(CONFIG_SENSORS_I5K_AMB)	+= i5k_amb.o
+obj-$(CONFIG_SENSORS_IEI_WT61P803_PUZZLE_HWMON) += iei-wt61p803-puzzle-hwmon.o
 obj-$(CONFIG_SENSORS_IBMAEM)	+= ibmaem.o
 obj-$(CONFIG_SENSORS_IBMPEX)	+= ibmpex.o
 obj-$(CONFIG_SENSORS_IBMPOWERNV)+= ibmpowernv.o
diff --git a/drivers/hwmon/iei-wt61p803-puzzle-hwmon.c b/drivers/hwmon/iei-wt61p803-puzzle-hwmon.c
new file mode 100644
index 000000000000..f221e2fc6312
--- /dev/null
+++ b/drivers/hwmon/iei-wt61p803-puzzle-hwmon.c
@@ -0,0 +1,410 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/* iEi WT61P803 PUZZLE MCU HWMON Driver
+ *
+ * Copyright (C) 2020 Sartura Ltd.
+ * Author: Luka Kovacic <luka.kovacic@sartura.hr>
+ */
+
+#include <linux/err.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/hwmon.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/math64.h>
+#include <linux/mfd/iei-wt61p803-puzzle.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define IEI_WT61P803_PUZZLE_HWMON_MAX_TEMP_NUM 2
+#define IEI_WT61P803_PUZZLE_HWMON_MAX_FAN_NUM 5
+#define IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM 2
+#define IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_VAL 255
+
+/**
+ * struct iei_wt61p803_puzzle_thermal_cooling_device - Thermal cooling device instance
+ *
+ * @mcu_hwmon:		MCU HWMON struct pointer
+ * @tcdev:		Thermal cooling device pointer
+ * @name:		Thermal cooling device name
+ * @pwm_channel:	PWM channel (0 or 1)
+ * @cooling_levels:	Thermal cooling device cooling levels
+ */
+struct iei_wt61p803_puzzle_thermal_cooling_device {
+	struct iei_wt61p803_puzzle_hwmon *mcu_hwmon;
+	struct thermal_cooling_device *tcdev;
+	char name[THERMAL_NAME_LENGTH];
+	int pwm_channel;
+	u8 *cooling_levels;
+};
+
+/**
+ * struct iei_wt61p803_puzzle_hwmon - MCU HWMON Driver
+ *
+ * @mcu:				MCU struct pointer
+ * @response_buffer			Global MCU response buffer allocation
+ * @thermal_cooling_dev_present:	Per-channel thermal cooling device control
+ * @cdev:				Per-channel thermal cooling device private structure
+ */
+struct iei_wt61p803_puzzle_hwmon {
+	struct iei_wt61p803_puzzle *mcu;
+	unsigned char *response_buffer;
+	bool thermal_cooling_dev_present[IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM];
+	struct iei_wt61p803_puzzle_thermal_cooling_device
+		*cdev[IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM];
+};
+
+#define raw_temp_to_milidegree_celsius(x) (((x) - 0x80) * 1000)
+static int iei_wt61p803_puzzle_read_temp_sensor(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon,
+						int channel, long *value)
+{
+	unsigned char *resp_buf = mcu_hwmon->response_buffer;
+	static unsigned char temp_sensor_ntc_cmd[4] = {
+		IEI_WT61P803_PUZZLE_CMD_HEADER_START,
+		IEI_WT61P803_PUZZLE_CMD_TEMP,
+		IEI_WT61P803_PUZZLE_CMD_TEMP_ALL
+	};
+	size_t reply_size = 0;
+	int ret;
+
+	ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, temp_sensor_ntc_cmd,
+						sizeof(temp_sensor_ntc_cmd), resp_buf,
+						&reply_size);
+
+	if (ret)
+		return ret;
+
+	/* Check the number of NTC values (should be 0x32/'2') */
+	if (resp_buf[3] != 0x32)
+		return -EIO;
+
+	*value = raw_temp_to_milidegree_celsius(resp_buf[4 + channel]);
+
+	return 0;
+}
+
+#define raw_fan_val_to_rpm(x, y) ((((x) << 8 | (y)) / 2) * 60)
+static int iei_wt61p803_puzzle_read_fan_speed(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon,
+					      int channel, long *value)
+{
+	unsigned char *resp_buf = mcu_hwmon->response_buffer;
+	unsigned char fan_speed_cmd[4] = {};
+	size_t reply_size = 0;
+	int ret;
+
+	fan_speed_cmd[0] = IEI_WT61P803_PUZZLE_CMD_HEADER_START;
+	fan_speed_cmd[1] = IEI_WT61P803_PUZZLE_CMD_FAN;
+	fan_speed_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_RPM(channel);
+
+	ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, fan_speed_cmd,
+						sizeof(fan_speed_cmd), resp_buf,
+						&reply_size);
+	if (ret)
+		return ret;
+
+	*value = raw_fan_val_to_rpm(resp_buf[3], resp_buf[4]);
+
+	return 0;
+}
+
+static int iei_wt61p803_puzzle_write_pwm_channel(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon,
+						 int channel, long pwm_set_val)
+{
+	unsigned char *resp_buf = mcu_hwmon->response_buffer;
+	unsigned char pwm_set_cmd[6] = {};
+	size_t reply_size = 0;
+	int ret;
+
+	pwm_set_cmd[0] = IEI_WT61P803_PUZZLE_CMD_HEADER_START;
+	pwm_set_cmd[1] = IEI_WT61P803_PUZZLE_CMD_FAN;
+	pwm_set_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM_WRITE;
+	pwm_set_cmd[3] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM(channel);
+	pwm_set_cmd[4] = (unsigned char)pwm_set_val;
+
+	ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, pwm_set_cmd,
+						sizeof(pwm_set_cmd), resp_buf,
+						&reply_size);
+	if (ret)
+		return ret;
+
+	if (!(resp_buf[0] == IEI_WT61P803_PUZZLE_CMD_HEADER_START &&
+	      resp_buf[1] == IEI_WT61P803_PUZZLE_CMD_RESPONSE_OK &&
+	      resp_buf[2] == IEI_WT61P803_PUZZLE_CHECKSUM_RESPONSE_OK))
+		return -EIO;
+
+	return 0;
+}
+
+static int iei_wt61p803_puzzle_read_pwm_channel(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon,
+						int channel, long *value)
+{
+	unsigned char *resp_buf = mcu_hwmon->response_buffer;
+	unsigned char pwm_get_cmd[5] = {};
+	size_t reply_size = 0;
+	int ret;
+
+	pwm_get_cmd[0] = IEI_WT61P803_PUZZLE_CMD_HEADER_START;
+	pwm_get_cmd[1] = IEI_WT61P803_PUZZLE_CMD_FAN;
+	pwm_get_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM_READ;
+	pwm_get_cmd[3] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM(channel);
+
+	ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, pwm_get_cmd,
+						sizeof(pwm_get_cmd), resp_buf,
+						&reply_size);
+	if (ret)
+		return ret;
+
+	if (resp_buf[2] != IEI_WT61P803_PUZZLE_CMD_FAN_PWM_READ)
+		return -EIO;
+
+	*value = resp_buf[3];
+
+	return 0;
+}
+
+static int iei_wt61p803_puzzle_read(struct device *dev, enum hwmon_sensor_types type,
+				    u32 attr, int channel, long *val)
+{
+	struct iei_wt61p803_puzzle_hwmon *mcu_hwmon = dev_get_drvdata(dev->parent);
+	int ret;
+
+	switch (type) {
+	case hwmon_pwm:
+		ret = iei_wt61p803_puzzle_read_pwm_channel(mcu_hwmon, channel, val);
+		return ret;
+	case hwmon_fan:
+		ret = iei_wt61p803_puzzle_read_fan_speed(mcu_hwmon, channel, val);
+		return ret;
+	case hwmon_temp:
+		ret = iei_wt61p803_puzzle_read_temp_sensor(mcu_hwmon, channel, val);
+		return ret;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int iei_wt61p803_puzzle_write(struct device *dev, enum hwmon_sensor_types type,
+				     u32 attr, int channel, long val)
+{
+	struct iei_wt61p803_puzzle_hwmon *mcu_hwmon = dev_get_drvdata(dev->parent);
+
+	if (attr != hwmon_pwm_input)
+		return -EINVAL;
+	if (mcu_hwmon->thermal_cooling_dev_present[channel]) {
+		/*
+		 * The Thermal Framework has already claimed this specific PWM
+		 * channel.
+		 */
+		return -EBUSY;
+	}
+	return iei_wt61p803_puzzle_write_pwm_channel(mcu_hwmon, channel, val);
+}
+
+static umode_t iei_wt61p803_puzzle_is_visible(const void *data, enum hwmon_sensor_types type,
+					      u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+			return 0644;
+		default:
+			return 0;
+		}
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_input:
+			return 0444;
+		default:
+			return 0;
+		}
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+			return 0444;
+		default:
+			return 0;
+		}
+	default:
+		return 0;
+	}
+}
+
+static const struct hwmon_ops iei_wt61p803_puzzle_hwmon_ops = {
+	.is_visible = iei_wt61p803_puzzle_is_visible,
+	.read = iei_wt61p803_puzzle_read,
+	.write = iei_wt61p803_puzzle_write,
+};
+
+static const struct hwmon_channel_info *iei_wt61p803_puzzle_info[] = {
+	HWMON_CHANNEL_INFO(pwm,
+			   HWMON_PWM_INPUT,
+			   HWMON_PWM_INPUT),
+	HWMON_CHANNEL_INFO(fan,
+			   HWMON_F_INPUT,
+			   HWMON_F_INPUT,
+			   HWMON_F_INPUT,
+			   HWMON_F_INPUT,
+			   HWMON_F_INPUT),
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT,
+			   HWMON_T_INPUT),
+	NULL
+};
+
+static const struct hwmon_chip_info iei_wt61p803_puzzle_chip_info = {
+	.ops = &iei_wt61p803_puzzle_hwmon_ops,
+	.info = iei_wt61p803_puzzle_info,
+};
+
+static int iei_wt61p803_puzzle_get_max_state(struct thermal_cooling_device *tcdev,
+					     unsigned long *state)
+{
+	*state = IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_VAL;
+
+	return 0;
+}
+
+static int iei_wt61p803_puzzle_get_cur_state(struct thermal_cooling_device *tcdev,
+					     unsigned long *state)
+{
+	struct iei_wt61p803_puzzle_thermal_cooling_device *cdev = tcdev->devdata;
+	struct iei_wt61p803_puzzle_hwmon *mcu_hwmon = cdev->mcu_hwmon;
+	long value;
+	int ret;
+
+	ret = iei_wt61p803_puzzle_read_pwm_channel(mcu_hwmon, cdev->pwm_channel, &value);
+	if (ret)
+		return ret;
+
+	*state = value;
+
+	return 0;
+}
+
+static int iei_wt61p803_puzzle_set_cur_state(struct thermal_cooling_device *tcdev,
+					     unsigned long state)
+{
+	struct iei_wt61p803_puzzle_thermal_cooling_device *cdev = tcdev->devdata;
+	struct iei_wt61p803_puzzle_hwmon *mcu_hwmon = cdev->mcu_hwmon;
+
+	return iei_wt61p803_puzzle_write_pwm_channel(mcu_hwmon, cdev->pwm_channel, state);
+}
+
+static const struct thermal_cooling_device_ops iei_wt61p803_puzzle_cooling_ops = {
+	.get_max_state = iei_wt61p803_puzzle_get_max_state,
+	.get_cur_state = iei_wt61p803_puzzle_get_cur_state,
+	.set_cur_state = iei_wt61p803_puzzle_set_cur_state,
+};
+
+static int iei_wt61p803_puzzle_enable_thermal_cooling_dev(struct device *dev,
+						struct fwnode_handle *child,
+						struct iei_wt61p803_puzzle_hwmon *mcu_hwmon)
+{
+	struct iei_wt61p803_puzzle_thermal_cooling_device *cdev;
+	int ret, num_levels;
+	u32 pwm_channel;
+
+	ret = fwnode_property_read_u32(child, "reg", &pwm_channel);
+	if (ret)
+		return ret;
+
+	mcu_hwmon->thermal_cooling_dev_present[pwm_channel] = true;
+
+	num_levels = fwnode_property_read_u8_array(child, "cooling-levels", NULL, 0);
+	if (num_levels > 0) {
+		cdev = devm_kzalloc(dev, sizeof(*cdev), GFP_KERNEL);
+		if (!cdev)
+			return -ENOMEM;
+
+		cdev->cooling_levels = devm_kzalloc(dev, num_levels, GFP_KERNEL);
+		if (!cdev->cooling_levels)
+			return -ENOMEM;
+
+		ret = fwnode_property_read_u8_array(child, "cooling-levels",
+						    cdev->cooling_levels,
+						    num_levels);
+		if (ret) {
+			dev_err(dev, "Couldn't read property 'cooling-levels'");
+			return ret;
+		}
+
+		snprintf(cdev->name, THERMAL_NAME_LENGTH, "iei_wt61p803_puzzle_%d", pwm_channel);
+
+		cdev->tcdev = devm_thermal_of_cooling_device_register(dev, NULL,
+				cdev->name, cdev, &iei_wt61p803_puzzle_cooling_ops);
+		if (IS_ERR(cdev->tcdev))
+			return PTR_ERR(cdev->tcdev);
+
+		cdev->mcu_hwmon = mcu_hwmon;
+		cdev->pwm_channel = pwm_channel;
+
+		mcu_hwmon->cdev[pwm_channel] = cdev;
+	}
+	return 0;
+}
+
+static int iei_wt61p803_puzzle_hwmon_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct iei_wt61p803_puzzle *mcu = dev_get_drvdata(dev->parent);
+	struct iei_wt61p803_puzzle_hwmon *mcu_hwmon;
+	struct fwnode_handle *child;
+	struct device *hwmon_dev;
+	int ret;
+
+	mcu_hwmon = devm_kzalloc(dev, sizeof(*mcu_hwmon), GFP_KERNEL);
+	if (!mcu_hwmon)
+		return -ENOMEM;
+
+	mcu_hwmon->response_buffer = devm_kzalloc(dev, IEI_WT61P803_PUZZLE_BUF_SIZE, GFP_KERNEL);
+	if (!mcu_hwmon->response_buffer)
+		return -ENOMEM;
+
+	mcu_hwmon->mcu = mcu;
+	platform_set_drvdata(pdev, mcu_hwmon);
+
+	hwmon_dev = devm_hwmon_device_register_with_info(dev, "iei_wt61p803_puzzle",
+							 mcu_hwmon,
+							 &iei_wt61p803_puzzle_chip_info,
+							 NULL);
+
+	if (IS_ERR(hwmon_dev))
+		return PTR_ERR(hwmon_dev);
+
+	/* Control fans via PWM lines via Linux Kernel */
+	if (IS_ENABLED(CONFIG_THERMAL)) {
+		device_for_each_child_node(dev, child) {
+			ret = iei_wt61p803_puzzle_enable_thermal_cooling_dev(dev, child, mcu_hwmon);
+			if (ret) {
+				dev_err(dev, "Enabling the PWM fan failed\n");
+				fwnode_handle_put(child);
+				return ret;
+			}
+		}
+	}
+	return 0;
+}
+
+static const struct of_device_id iei_wt61p803_puzzle_hwmon_id_table[] = {
+	{ .compatible = "iei,wt61p803-puzzle-hwmon" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, iei_wt61p803_puzzle_hwmon_id_table);
+
+static struct platform_driver iei_wt61p803_puzzle_hwmon_driver = {
+	.driver = {
+		.name = "iei-wt61p803-puzzle-hwmon",
+		.of_match_table = iei_wt61p803_puzzle_hwmon_id_table,
+	},
+	.probe = iei_wt61p803_puzzle_hwmon_probe,
+};
+
+module_platform_driver(iei_wt61p803_puzzle_hwmon_driver);
+
+MODULE_DESCRIPTION("iEi WT61P803 PUZZLE MCU HWMON Driver");
+MODULE_AUTHOR("Luka Kovacic <luka.kovacic@sartura.hr>");
+MODULE_LICENSE("GPL");