Re: [PATCH v2 3/7] drivers: hwmon: Add the iEi WT61P803 PUZZLE HWMON driver

Luka Kovacic
2020-10-06T10:00:32Z

On Wed, Sep 30, 2020 at 10:31 PM Guenter Roeck <linux@roeck-us.net> wrote:
>
> On Sat, Sep 26, 2020 at 03:55:10PM +0200, Luka Kovacic 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.
> >
> > 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 | 511 ++++++++++++++++++++++
> > 3 files changed, 520 insertions(+)
> > create mode 100644 drivers/hwmon/iei-wt61p803-puzzle-hwmon.c
> >
> > 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..2691b943936b
> > --- /dev/null
> > +++ b/drivers/hwmon/iei-wt61p803-puzzle-hwmon.c
> > @@ -0,0 +1,511 @@
> > +// 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
> > + * @lock General member lock
> > + * @response_buffer Global MCU response buffer allocation
> > + * @temp_sensor_val: Temperature sensor values
> > + * @fan_speed_val: FAN speed (RPM) values
> > + * @pwm_val: PWM values (0-255)
> > + * @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;
> > + struct mutex lock;
> > + unsigned char *response_buffer;
> > + int temp_sensor_val[IEI_WT61P803_PUZZLE_HWMON_MAX_TEMP_NUM];
> > + int fan_speed_val[IEI_WT61P803_PUZZLE_HWMON_MAX_FAN_NUM];
> > + int pwm_val[IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_NUM];
> > + 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) ((int)((x - 0x80)*1000))
>
> Spaces around '*', please, and (x). checkpatch --strict will tell about it.
>
> > +static int iei_wt61p803_puzzle_read_temp_sensor
> > +(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon, int channel, int *value)
>
> Odd multi-line alignment. Please use either
>
> static int
> iei_wt61p803_puzzle_read_temp_sensor(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon, int channel,
> int *value)
>
> or
>
> static int iei_wt61p803_puzzle_read_temp_sensor(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon,
> int channel, int *value)
>
> There are lots of those in this driver. Please run
> checkpatch --strict and fix what it reports.
>
> > +{
> > + int ret;
> > + size_t reply_size = 0;
> > + unsigned char *resp_buf = mcu_hwmon->response_buffer;
> > + unsigned char temp_sensor_ntc_cmd[4] = {
> > + IEI_WT61P803_PUZZLE_CMD_HEADER_START,
> > + IEI_WT61P803_PUZZLE_CMD_TEMP,
> > + IEI_WT61P803_PUZZLE_CMD_TEMP_ALL
> > + };
> > +
> > + if (channel > 1 && channel < 0)
> > + return -EINVAL;
>
> Unnecessary range check.
>
> > +
> > + mutex_lock(&mcu_hwmon->lock);
> > + ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu,
> > + temp_sensor_ntc_cmd, sizeof(temp_sensor_ntc_cmd),
> > + resp_buf, &reply_size);
>
> if (ret < 0)
> goto unlock;
>
> > + if (!ret) {
> > + /* Check the number of NTC values (should be 0x32/'2') */
> > + if (resp_buf[3] == 0x32) {
> > + /* Write values to the struct */
> > + mcu_hwmon->temp_sensor_val[0] =
> > + raw_temp_to_milidegree_celsius(resp_buf[4]);
> > + mcu_hwmon->temp_sensor_val[1] =
> > + raw_temp_to_milidegree_celsius(resp_buf[5]);
>
> What is the point of storing the return values in mcu_hwmon->temp_sensor_val[] ?
>
> > + }
> > +
>
> Unnecessary empty line. checkpatch --strict reports this.
>
> > + }
> > + *value = mcu_hwmon->temp_sensor_val[channel];
>
> unlock:
>
> > + mutex_unlock(&mcu_hwmon->lock);
> > +
> > + return ret;
> > +}
> > +
> > +#define raw_fan_val_to_rpm(x, y) ((int)(((x)<<8|(y))/2)*60)
> > +static int iei_wt61p803_puzzle_read_fan_speed
> > +(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon, int channel, int *value)
> > +{
> > + int ret;
> > + size_t reply_size = 0;
> > + unsigned char *resp_buf = mcu_hwmon->response_buffer;
> > + unsigned char fan_speed_cmd[4] = {
> > + IEI_WT61P803_PUZZLE_CMD_HEADER_START,
> > + IEI_WT61P803_PUZZLE_CMD_FAN,
> > + IEI_WT61P803_PUZZLE_CMD_FAN_RPM_0
> > + };
> > +
> > + switch (channel) {
> > + case 0:
> > + fan_speed_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_RPM_0;
> > + break;
> > + case 1:
> > + fan_speed_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_RPM_1;
> > + break;
> > + case 2:
> > + fan_speed_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_RPM_2;
> > + break;
> > + case 3:
> > + fan_speed_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_RPM_3;
> > + break;
> > + case 4:
> > + fan_speed_cmd[2] = IEI_WT61P803_PUZZLE_CMD_FAN_RPM_4;
> > + break;
> > + default:
> > + return -EINVAL;
> > + }
>
> This would be much simpler written as
>
> static const u8 fan_speed_cmds[] = {
> IEI_WT61P803_PUZZLE_CMD_FAN_RPM_0,
> IEI_WT61P803_PUZZLE_CMD_FAN_RPM_1,
> IEI_WT61P803_PUZZLE_CMD_FAN_RPM_2,
> IEI_WT61P803_PUZZLE_CMD_FAN_RPM_3,
> IEI_WT61P803_PUZZLE_CMD_FAN_RPM_4
> };
> ...
>
> fan_speed_cmd[2] = fan_speed_cmds[channel];
>
> > +
> > + mutex_lock(&mcu_hwmon->lock);
> > + ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, fan_speed_cmd,
> > + sizeof(fan_speed_cmd), resp_buf, &reply_size);
>
> if (ret < 0)
> goto unlock;
>
> > + if (!ret)
> > + mcu_hwmon->fan_speed_val[channel] = raw_fan_val_to_rpm(resp_buf[3],
> > + resp_buf[4]);
> > +
> > + *value = mcu_hwmon->fan_speed_val[channel];
>
> What exactly is the point of storing the result in
> mcu_hwmon->fan_speed_val[channel] ?
>
> I won't comment about similar code again, but please drop any such
> unnecessary arrays.
>
> > + mutex_unlock(&mcu_hwmon->lock);
> > +
> > + return 0;
> > +}
> > +
> > +static int iei_wt61p803_puzzle_write_pwm_channel
> > +(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon, int channel, long pwm_set_val)
> > +{
> > + int ret;
> > + size_t reply_size = 0;
> > + unsigned char *resp_buf = mcu_hwmon->response_buffer;
> > + unsigned char pwm_set_cmd[6] = {
> > + IEI_WT61P803_PUZZLE_CMD_HEADER_START,
> > + IEI_WT61P803_PUZZLE_CMD_FAN,
> > + IEI_WT61P803_PUZZLE_CMD_FAN_PWM_WRITE,
> > + IEI_WT61P803_PUZZLE_CMD_FAN_PWM_0,
> > + 0x00
> > + };
> > +
> > + switch (channel) {
> > + case 0:
> > + pwm_set_cmd[3] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM_0;
> > + break;
> > + case 1:
> > + pwm_set_cmd[3] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM_1;
> > + break;
> > + default:
> > + return -EINVAL;
> > + }
>
> Same as above - it would be much simpler to have IEI_WT61P803_PUZZLE_CMD_FAN_PWM_0
> and IEI_WT61P803_PUZZLE_CMD_FAN_PWM_1 in an array and get it from there.
> The range check is unnecessary.
>
> > +
> > + if (pwm_set_val < 0 || pwm_set_val > IEI_WT61P803_PUZZLE_HWMON_MAX_PWM_VAL)
> > + return -EINVAL;
> > +
> > + /* Add the PWM value to the command */
> > + pwm_set_cmd[4] = (char)pwm_set_val;
>
> I think this typecast is quite unnecessary. Besides, it is wrong, since the
> value is an unsigned char.
>
> > +
> > + mutex_lock(&mcu_hwmon->lock);
> > + ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, pwm_set_cmd,
> > + sizeof(pwm_set_cmd), resp_buf, &reply_size);
>
> if (ret < 0)
> goto unlock;
>
> > + if (!ret) {
> > + /* Store the PWM value */
>
> What for ?
>
> Ah yes, I think I finally get it: All this odd handling is to be able to ignore
> errors. But that is not acceptable. If there is an error, report it to the user.
> You can't really claim no error to the user when the value wasn't stored.
>
> > + 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)
> > + mcu_hwmon->pwm_val[channel] = (int)pwm_set_val;
> > + }
> > + mutex_unlock(&mcu_hwmon->lock);
> > +
> > + return 0;
> > +}
> > +
> > +static int iei_wt61p803_puzzle_read_pwm_channel
> > +(struct iei_wt61p803_puzzle_hwmon *mcu_hwmon, int channel, int *value)
> > +{
> > + int ret;
> > + size_t reply_size = 0;
> > + unsigned char *resp_buf = mcu_hwmon->response_buffer;
> > + unsigned char pwm_get_cmd[5] = {
> > + IEI_WT61P803_PUZZLE_CMD_HEADER_START,
> > + IEI_WT61P803_PUZZLE_CMD_FAN,
> > + IEI_WT61P803_PUZZLE_CMD_FAN_PWM_READ,
> > + IEI_WT61P803_PUZZLE_CMD_FAN_PWM_0
> > + };
> > +
> > + switch (channel) {
> > + case 0:
> > + pwm_get_cmd[3] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM_0;
> > + break;
> > + case 1:
> > + pwm_get_cmd[3] = IEI_WT61P803_PUZZLE_CMD_FAN_PWM_1;
> > + break;
> > + default:
> > + return -EINVAL;
> > + }
>
> Same comments as before.
>
> > +
> > + mutex_lock(&mcu_hwmon->lock);
> > + ret = iei_wt61p803_puzzle_write_command(mcu_hwmon->mcu, pwm_get_cmd,
> > + sizeof(pwm_get_cmd), resp_buf, &reply_size);
> > + if (!ret) {
> > + /* Store the PWM value */
> > + if (resp_buf[2] == IEI_WT61P803_PUZZLE_CMD_FAN_PWM_READ)
> > + mcu_hwmon->pwm_val[channel] = (int)resp_buf[3];
> > + }
>
> Same comments as before.
>
> > + *value = mcu_hwmon->pwm_val[channel];
> > + mutex_unlock(&mcu_hwmon->lock);
> > +
> > + 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, value;
> > +
> > + switch (type) {
> > + case hwmon_pwm:
> > + if (attr != hwmon_pwm_input)
> > + return -ENODEV;
> > + ret = iei_wt61p803_puzzle_read_pwm_channel(mcu_hwmon, channel, &value);
> > + if (ret)
> > + return ret;
> > + *val = (long)value;
> > + return ret;
> > + case hwmon_fan:
> > + if (attr != hwmon_fan_input)
> > + return -ENODEV;
> > + ret = iei_wt61p803_puzzle_read_fan_speed(mcu_hwmon, channel, &value);
> > + if (ret)
> > + return ret;
> > + *val = (long)value;
>
> Unncecssary typecast. Plase check all typecasts and keep only those which
> are really needed (if there are any).
>
> > + return ret;
>
> ret is 0 here.
>
> > + case hwmon_temp:
> > + if (attr != hwmon_temp_input)
> > + return -ENODEV;
> > + ret = iei_wt61p803_puzzle_read_temp_sensor(mcu_hwmon, channel, &value);
> > + if (ret)
> > + return ret;
> > + *val = (long)value;
> > + return ret;
>
> ret is 0 here. That is sprinkled through the code. Please
> replace with "return 0;" everywhere.
>
> > + default:
> > + return -ENODEV;
> > + }
> > +}
> > +
> > +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);
> > +
> > + switch (type) {
> > + case hwmon_pwm:
> > + if (attr != hwmon_pwm_input)
> > + return -ENODEV;
> > + if (mcu_hwmon->thermal_cooling_dev_present[channel]) {
> > + /*
> > + * The Thermal Framework has already claimed this specific PWM
> > + * channel.
> > + */
> > + return -EBUSY;
> > + }
> This won't happen (the attribute is read-only in this case), and the check is
> therefore unnecessary and just adds confusion.
>
> > + return iei_wt61p803_puzzle_write_pwm_channel(mcu_hwmon, channel, val);
> > + default:
> > + return -ENODEV;
> > + }
>
> Unless there is a plan to make other types writable, this switch statement
> is unnecessary. Only pwm attributes are writeable, after all, so the code
> won't be called for anything else.
>
> > +}
> > +
> > +static umode_t iei_wt61p803_puzzle_is_visible(const void *data,
> > + enum hwmon_sensor_types type, u32 attr, int channel)
> > +{
> > + const struct iei_wt61p803_puzzle_hwmon *mcu_hwmon = data;
> > +
> > + switch (type) {
> > + case hwmon_pwm:
> > + switch (attr) {
> > + case hwmon_pwm_input:
> > + if (mcu_hwmon->thermal_cooling_dev_present[channel])
> > + return 0444;
> > + 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;
> > +
> > + int ret, value;
> > +
> > + if (!mcu_hwmon)
> > + return -EINVAL;
> > +
> > + ret = iei_wt61p803_puzzle_read_pwm_channel(mcu_hwmon,
> > + cdev->pwm_channel, &value);
> > + if (ret)
> > + return ret;
> > +
> > + *state = (unsigned long)value;
> > +
> > + return 0;
> > +}
>
> Missing empty line. checkpatch --strict reports this.
>
> > +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;
> > +
> > + if (!mcu_hwmon)
> > + return -EINVAL;
> > +
> > + 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)
> > +{
> > + u32 pwm_channel;
> > + int ret, num_levels;
> > +
> > + struct iei_wt61p803_puzzle_thermal_cooling_device *cdev;
> > +
> > + ret = fwnode_property_read_u32(child, "reg", &pwm_channel);
> > + if (ret)
> > + return ret;
> > +
> > + mutex_lock(&mcu_hwmon->lock);
> > + mcu_hwmon->thermal_cooling_dev_present[pwm_channel] = true;
> > + mutex_unlock(&mcu_hwmon->lock);
> > +
> > + 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;
> > +
> > + mutex_lock(&mcu_hwmon->lock);
> > + mcu_hwmon->cdev[pwm_channel] = cdev;
> > + mutex_unlock(&mcu_hwmon->lock);
> > + }
> > + return 0;
> > +}
> > +
> > +static int iei_wt61p803_puzzle_hwmon_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct fwnode_handle *child;
> > + struct iei_wt61p803_puzzle_hwmon *mcu_hwmon;
> > + struct iei_wt61p803_puzzle *mcu = dev_get_drvdata(dev->parent);
> > + 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;
> > + mutex_init(&mcu_hwmon->lock);
> > + 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);
> > +
> > + /* 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");
> > --
> > 2.26.2
> >

Hello Guenter,

Thanks for reviewing the patch.
I'll resolve the code styling issues, fix the error handling, and
other issues you
have pointed out.

Kind regards,
Luka