Re: [PATCH v2] hwmon: (aquacomputer_d5next) Add support for Aquacomputer Octo

[Guenter Roeck <linux@xxxxxxxxxxxx>]

On 3/26/22 03:12, Aleksa Savic wrote:
> Extend aquacomputer_d5next driver to expose hardware temperature sensors
> and fans of the Aquacomputer Octo fan controller, which communicates
> through a proprietary USB HID protocol.
>
> Four temperature sensors and eight PWM controllable fans are available.
> Additionally, serial number, firmware version and power-on count are
> exposed through debugfs.
>
> This driver has been tested on x86_64.
>
> Signed-off-by: Aleksa Savic <savicaleksa83@xxxxxxxxx>
> ---
> Changes in v2:
> - Fixed formatting
> - HID report values from device are now being converted sooner
> - aqc_pwm_to_percent() is now range checked
> - Put pointers to labels in aqc_data
> - Simplified checksum calculation call
> ---
>   Documentation/hwmon/aquacomputer_d5next.rst |   4 +
>   drivers/hwmon/Kconfig                       |   7 +-
>   drivers/hwmon/aquacomputer_d5next.c         | 446 +++++++++++++++++---
>   3 files changed, 404 insertions(+), 53 deletions(-)
>
> diff --git a/Documentation/hwmon/aquacomputer_d5next.rst b/Documentation/hwmon/aquacomputer_d5next.rst
> index 3373e27b707d..e69f718caf5b 100644
> --- a/Documentation/hwmon/aquacomputer_d5next.rst
> +++ b/Documentation/hwmon/aquacomputer_d5next.rst
> @@ -7,6 +7,7 @@ Supported devices:
>   
>   * Aquacomputer D5 Next watercooling pump
>   * Aquacomputer Farbwerk 360 RGB controller
> +* Aquacomputer Octo fan controller
>   
>   Author: Aleksa Savic
>   
> @@ -28,6 +29,9 @@ seems to require sending it a complete configuration. That includes addressable
>   RGB LEDs, for which there is no standard sysfs interface. Thus, that task is
>   better suited for userspace tools.
>   
> +The Octo exposes four temperature sensors and eight PWM controllable fans, along
> +with their speed (in RPM), power, voltage and current.
> +
>   The Farbwerk 360 exposes four temperature sensors. Depending on the device,
>   not all sysfs and debugfs entries will be available.
>   
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index db8bc55e5f50..5beadd8a0932 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -256,11 +256,12 @@ config SENSORS_AHT10
>   	  will be called aht10.
>   
>   config SENSORS_AQUACOMPUTER_D5NEXT
> -	tristate "Aquacomputer D5 Next watercooling pump"
> +	tristate "Aquacomputer D5 Next, Octo and Farbwerk 360"
>   	depends on USB_HID
>   	help
> -	  If you say yes here you get support for the Aquacomputer D5 Next
> -	  watercooling pump sensors.
> +	  If you say yes here you get support for sensors and fans of
> +	  the Aquacomputer D5 Next watercooling pump, Octo fan
> +	  controller and Farbwerk 360 RGB controller, where available.
>   
>   	  This driver can also be built as a module. If so, the module
>   	  will be called aquacomputer_d5next.
> diff --git a/drivers/hwmon/aquacomputer_d5next.c b/drivers/hwmon/aquacomputer_d5next.c
> index 525809cf7c95..1711957a9ea7 100644
> --- a/drivers/hwmon/aquacomputer_d5next.c
> +++ b/drivers/hwmon/aquacomputer_d5next.c
> @@ -1,6 +1,6 @@
>   // SPDX-License-Identifier: GPL-2.0+
>   /*
> - * hwmon driver for Aquacomputer devices (D5 Next, Farbwerk 360)
> + * hwmon driver for Aquacomputer devices (D5 Next, Farbwerk 360, Octo)
>    *
>    * Aquacomputer devices send HID reports (with ID 0x01) every second to report
>    * sensor values.
> @@ -8,23 +8,27 @@
>    * Copyright 2021 Aleksa Savic <savicaleksa83@xxxxxxxxx>
>    */
>   
> +#include <linux/crc16.h>
>   #include <linux/debugfs.h>
>   #include <linux/hid.h>
>   #include <linux/hwmon.h>
>   #include <linux/jiffies.h>
>   #include <linux/module.h>
> +#include <linux/mutex.h>
>   #include <linux/seq_file.h>
>   #include <asm/unaligned.h>
>   
>   #define USB_VENDOR_ID_AQUACOMPUTER	0x0c70
>   #define USB_PRODUCT_ID_D5NEXT		0xf00e
>   #define USB_PRODUCT_ID_FARBWERK360	0xf010
> +#define USB_PRODUCT_ID_OCTO		0xf011
>   
> -enum kinds { d5next, farbwerk360 };
> +enum kinds { d5next, farbwerk360, octo };
>   
>   static const char *const aqc_device_names[] = {
>   	[d5next] = "d5next",
> -	[farbwerk360] = "farbwerk360"
> +	[farbwerk360] = "farbwerk360",
> +	[octo] = "octo"
>   };
>   
>   #define DRIVER_NAME			"aquacomputer_d5next"
> @@ -35,6 +39,18 @@ static const char *const aqc_device_names[] = {
>   #define SERIAL_SECOND_PART		5
>   #define FIRMWARE_VERSION		13
>   
> +#define CTRL_REPORT_ID			0x03
> +
> +/* The HID report that the official software always sends
> + * after writing values, currently same for all devices
> + */
> +#define SECONDARY_CTRL_REPORT_ID	0x02
> +#define SECONDARY_CTRL_REPORT_SIZE	0x0B
> +
> +static u8 secondary_ctrl_report[] = {
> +	0x02, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x34, 0xC6
> +};
> +
>   /* Register offsets for the D5 Next pump */
>   #define D5NEXT_POWER_CYCLES		24
>   
> @@ -55,12 +71,38 @@ static const char *const aqc_device_names[] = {
>   
>   /* Register offsets for the Farbwerk 360 RGB controller */
>   #define FARBWERK360_NUM_SENSORS		4
> -#define FARBWERK360_SENSOR_START		0x32
> +#define FARBWERK360_SENSOR_START	0x32
>   #define FARBWERK360_SENSOR_SIZE		0x02
>   #define FARBWERK360_SENSOR_DISCONNECTED	0x7FFF
>   
> +/* Register offsets for the Octo fan controller */
> +#define OCTO_POWER_CYCLES		0x18
> +#define OCTO_NUM_FANS			8
> +#define OCTO_FAN_PERCENT_OFFSET		0x00
> +#define OCTO_FAN_VOLTAGE_OFFSET		0x02
> +#define OCTO_FAN_CURRENT_OFFSET		0x04
> +#define OCTO_FAN_POWER_OFFSET		0x06
> +#define OCTO_FAN_SPEED_OFFSET		0x08
> +
> +static u8 octo_sensor_fan_offsets[] = { 0x7D, 0x8A, 0x97, 0xA4, 0xB1, 0xBE, 0xCB, 0xD8 };
> +
> +#define OCTO_NUM_SENSORS		4
> +#define OCTO_SENSOR_START		0x3D
> +#define OCTO_SENSOR_SIZE		0x02
> +#define OCTO_SENSOR_DISCONNECTED	0x7FFF
> +
> +#define OCTO_CTRL_REPORT_SIZE			0x65F
> +#define OCTO_CTRL_REPORT_CHECKSUM_OFFSET	0x65D
> +#define OCTO_CTRL_REPORT_CHECKSUM_START		0x01
> +#define OCTO_CTRL_REPORT_CHECKSUM_LENGTH	0x65C
> +
> +/* Fan speed registers in Octo control report (from 0-100%) */
> +static u16 octo_ctrl_fan_offsets[] = { 0x5B, 0xB0, 0x105, 0x15A, 0x1AF, 0x204, 0x259, 0x2AE };
> +
>   /* Labels for D5 Next */
> -#define L_D5NEXT_COOLANT_TEMP		"Coolant temp"
> +static const char *const label_d5next_temp[] = {
> +	"Coolant temp"
> +};
>   
>   static const char *const label_d5next_speeds[] = {
>   	"Pump speed",
> @@ -83,7 +125,7 @@ static const char *const label_d5next_current[] = {
>   	"Fan current"
>   };
>   
> -/* Labels for Farbwerk 360 temperature sensors */
> +/* Labels for Farbwerk 360 and Octo temperature sensors */
>   static const char *const label_temp_sensors[] = {
>   	"Sensor 1",
>   	"Sensor 2",
> @@ -91,32 +133,196 @@ static const char *const label_temp_sensors[] = {
>   	"Sensor 4"
>   };
>   
> +/* Labels for Octo */
> +static const char *const label_fan_speed[] = {
> +	"Fan 1 speed",
> +	"Fan 2 speed",
> +	"Fan 3 speed",
> +	"Fan 4 speed",
> +	"Fan 5 speed",
> +	"Fan 6 speed",
> +	"Fan 7 speed",
> +	"Fan 8 speed"
> +};
> +
> +static const char *const label_fan_power[] = {
> +	"Fan 1 power",
> +	"Fan 2 power",
> +	"Fan 3 power",
> +	"Fan 4 power",
> +	"Fan 5 power",
> +	"Fan 6 power",
> +	"Fan 7 power",
> +	"Fan 8 power"
> +};
> +
> +static const char *const label_fan_voltage[] = {
> +	"Fan 1 voltage",
> +	"Fan 2 voltage",
> +	"Fan 3 voltage",
> +	"Fan 4 voltage",
> +	"Fan 5 voltage",
> +	"Fan 6 voltage",
> +	"Fan 7 voltage",
> +	"Fan 8 voltage"
> +};
> +
> +static const char *const label_fan_current[] = {
> +	"Fan 1 current",
> +	"Fan 2 current",
> +	"Fan 3 current",
> +	"Fan 4 current",
> +	"Fan 5 current",
> +	"Fan 6 current",
> +	"Fan 7 current",
> +	"Fan 8 current"
> +};
> +
>   struct aqc_data {
>   	struct hid_device *hdev;
>   	struct device *hwmon_dev;
>   	struct dentry *debugfs;
> +	struct mutex mutex;	/* Used for locking access when reading and writing PWM values */
>   	enum kinds kind;
>   	const char *name;
>   
> +	int buffer_size;
> +	u8 *buffer;
> +	int checksum_start;
> +	int checksum_length;
> +	int checksum_offset;
> +
>   	/* General info, same across all devices */
>   	u32 serial_number[2];
>   	u16 firmware_version;
>   
> -	/* D5 Next specific - how many times the device was powered on */
> +	/* How many times the device was powered on */
>   	u32 power_cycles;
>   
>   	/* Sensor values */
>   	s32 temp_input[4];
> -	u16 speed_input[2];
> -	u32 power_input[2];
> -	u16 voltage_input[3];
> -	u16 current_input[2];
> +	u16 speed_input[8];
> +	u32 power_input[8];
> +	u16 voltage_input[8];
> +	u16 current_input[8];
> +
> +	/* Label values */
> +	const char *const *temp_label;
> +	const char *const *speed_label;
> +	const char *const *power_label;
> +	const char *const *voltage_label;
> +	const char *const *current_label;
>   
>   	unsigned long updated;
>   };
>   
> -static umode_t aqc_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr,
> -			      int channel)
> +static int aqc_percent_to_pwm(u16 val)
> +{
> +	return DIV_ROUND_CLOSEST(val * 255, 100 * 100);
> +}
> +
> +static int aqc_pwm_to_percent(long val)
> +{
> +	if (val < 0 || val > 255)
> +		return -EINVAL;
> +
> +	return DIV_ROUND_CLOSEST(val * 100 * 100, 255);

This is really centi-percent, or am I missing something ?

> +}
> +
> +/* Expects the mutex to be locked */
> +static int aqc_get_ctrl_data(struct aqc_data *priv)
> +{
> +	int ret;
> +
> +	memset(priv->buffer, 0x00, priv->buffer_size);
> +	ret = hid_hw_raw_request(priv->hdev, CTRL_REPORT_ID, priv->buffer, priv->buffer_size,
> +				 HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
> +	if (ret < 0)
> +		ret = -ENODATA;
> +
> +	return ret;
> +}
> +
> +/* Expects the mutex to be locked */
> +static int aqc_send_ctrl_data(struct aqc_data *priv)
> +{
> +	int ret;
> +	u16 checksum;
> +
> +	/* Init and xorout value for CRC-16/USB is 0xffff */
> +	checksum = crc16(0xffff, priv->buffer + priv->checksum_start, priv->checksum_length);
> +	checksum ^= 0xffff;
> +
> +	/* Place the new checksum at the end of the report */
> +	put_unaligned_be16(checksum, priv->buffer + priv->checksum_offset);
> +
> +	/* Send the patched up report back to the device */
> +	ret = hid_hw_raw_request(priv->hdev, CTRL_REPORT_ID, priv->buffer, priv->buffer_size,
> +				 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
> +	if (ret < 0)
> +		goto exit;

Please return directly.

> +
> +	/* The official software sends this report after every change, so do it here as well */
> +	ret = hid_hw_raw_request(priv->hdev, SECONDARY_CTRL_REPORT_ID, secondary_ctrl_report,
> +				 SECONDARY_CTRL_REPORT_SIZE, HID_FEATURE_REPORT,
> +				 HID_REQ_SET_REPORT);
> +exit:
> +	return ret;
> +}
> +
> +/* Refreshes the control buffer and returns value at offset */
> +static int aqc_get_ctrl_val(struct aqc_data *priv, int offset)
> +{
> +	int ret;
> +
> +	mutex_lock(&priv->mutex);
> +
> +	ret = aqc_get_ctrl_data(priv);
> +	if (ret < 0)
> +		goto unlock_and_return;
> +
> +	ret = get_unaligned_be16(priv->buffer + offset);
> +
> +unlock_and_return:
> +	mutex_unlock(&priv->mutex);
> +	return ret;
> +}
> +
> +static int aqc_set_ctrl_val(struct aqc_data *priv, int offset, long val, size_t size)
> +{
> +	int ret;
> +
> +	if (size < 1 || size > 4)
> +		return -EINVAL;
> +

I am sure I mentioned this before: The calling code controls this, and it is a constant.
The check is pointless, and so is the size parameter in the first place as it is always
called with a length of 2. Besides, it accepts a size of 3 without error and is
thus wrong anyway.

> +	mutex_lock(&priv->mutex);
> +
> +	ret = aqc_get_ctrl_data(priv);
> +	if (ret < 0)
> +		goto unlock_and_return;
> +
> +	switch (size) {
> +	case 4:
> +		put_unaligned_be32(val, priv->buffer + offset);
> +		break;
> +	case 2:
> +		put_unaligned_be16((u16)val, priv->buffer + offset);
> +		break;
> +	case 1:
> +		priv->buffer[offset] = val;
> +		break;

Same here: values other than 2 are not used. I am not inclined to accept this.
If there is future code that needs sizes other than 2, add it when needed, not now.

> +	default:
> +		break;
> +	}
> +
> +	ret = aqc_send_ctrl_data(priv);
> +
> +unlock_and_return:
> +	mutex_unlock(&priv->mutex);
> +	return ret;
> +}
> +
> +static umode_t aqc_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr, int channel)
>   {
>   	const struct aqc_data *priv = data;
>   
> @@ -128,17 +334,47 @@ static umode_t aqc_is_visible(const void *data, enum hwmon_sensor_types type, u3
>   				return 0444;
>   			break;
>   		case farbwerk360:
> +		case octo:
>   			return 0444;
>   		default:
>   			break;
>   		}
>   		break;
> +	case hwmon_pwm:
> +		switch (priv->kind) {
> +		case octo:
> +			switch (attr) {
> +			case hwmon_pwm_input:
> +				return 0644;
> +			default:
> +				break;
> +			}
> +			break;
> +		default:
> +			break;
> +		}
> +		break;
>   	case hwmon_fan:
>   	case hwmon_power:
> -	case hwmon_in:
>   	case hwmon_curr:
>   		switch (priv->kind) {
>   		case d5next:
> +			if (channel < 2)
> +				return 0444;
> +			break;
> +		case octo:
> +			return 0444;
> +		default:
> +			break;
> +		}
> +		break;
> +	case hwmon_in:
> +		switch (priv->kind) {
> +		case d5next:
> +			if (channel < 3)
> +				return 0444;
> +			break;
> +		case octo:
>   			return 0444;
>   		default:
>   			break;
> @@ -154,6 +390,7 @@ static umode_t aqc_is_visible(const void *data, enum hwmon_sensor_types type, u3
>   static int aqc_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
>   		    int channel, long *val)
>   {
> +	int ret;
>   	struct aqc_data *priv = dev_get_drvdata(dev);
>   
>   	if (time_after(jiffies, priv->updated + STATUS_UPDATE_INTERVAL))
> @@ -172,6 +409,18 @@ static int aqc_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
>   	case hwmon_power:
>   		*val = priv->power_input[channel];
>   		break;
> +	case hwmon_pwm:
> +		switch (priv->kind) {
> +		case octo:
> +			ret = aqc_get_ctrl_val(priv, octo_ctrl_fan_offsets[channel]);
> +			if (ret < 0)
> +				return ret;
> +
> +			*val = aqc_percent_to_pwm(ret);
> +		default:
> +			break;

Please don't do that. While it  saves a line of code,
the additional break; statement after the case statement doesn't really hurt,
and you'd have to add a fallthrough; otherwise anyway. Same further below.

Guenter

> +		}
> +		break;
>   	case hwmon_in:
>   		*val = priv->voltage_input[channel];
>   		break;
> @@ -192,49 +441,51 @@ static int aqc_read_string(struct device *dev, enum hwmon_sensor_types type, u32
>   
>   	switch (type) {
>   	case hwmon_temp:
> -		switch (priv->kind) {
> -		case d5next:
> -			*str = L_D5NEXT_COOLANT_TEMP;
> -			break;
> -		case farbwerk360:
> -			*str = label_temp_sensors[channel];
> -			break;
> -		default:
> -			break;
> -		}
> +		*str = priv->temp_label[channel];
>   		break;
>   	case hwmon_fan:
> -		switch (priv->kind) {
> -		case d5next:
> -			*str = label_d5next_speeds[channel];
> -			break;
> -		default:
> -			break;
> -		}
> +		*str = priv->speed_label[channel];
>   		break;
>   	case hwmon_power:
> -		switch (priv->kind) {
> -		case d5next:
> -			*str = label_d5next_power[channel];
> -			break;
> -		default:
> -			break;
> -		}
> +		*str = priv->power_label[channel];
>   		break;
>   	case hwmon_in:
> -		switch (priv->kind) {
> -		case d5next:
> -			*str = label_d5next_voltages[channel];
> -			break;
> -		default:
> -			break;
> -		}
> +		*str = priv->voltage_label[channel];
>   		break;
>   	case hwmon_curr:
> -		switch (priv->kind) {
> -		case d5next:
> -			*str = label_d5next_current[channel];
> -			break;
> +		*str = priv->current_label[channel];
> +		break;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +
> +	return 0;
> +}
> +
> +static int aqc_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
> +		     long val)
> +{
> +	int ret, pwm_value;
> +	struct aqc_data *priv = dev_get_drvdata(dev);
> +
> +	switch (type) {
> +	case hwmon_pwm:
> +		switch (attr) {
> +		case hwmon_pwm_input:
> +			switch (priv->kind) {
> +			case octo:
> +				pwm_value = aqc_pwm_to_percent(val);
> +				if (pwm_value < 0)
> +					return pwm_value;
> +
> +				ret = aqc_set_ctrl_val(priv, octo_ctrl_fan_offsets[channel],
> +						       pwm_value, 2);
> +				if (ret < 0)
> +					return ret;
> +				break;
> +			default:
> +				break;
> +			}
>   		default:
>   			break;
>   		}
> @@ -250,6 +501,7 @@ static const struct hwmon_ops aqc_hwmon_ops = {
>   	.is_visible = aqc_is_visible,
>   	.read = aqc_read,
>   	.read_string = aqc_read_string,
> +	.write = aqc_write
>   };
>   
>   static const struct hwmon_channel_info *aqc_info[] = {
> @@ -259,16 +511,48 @@ static const struct hwmon_channel_info *aqc_info[] = {
>   			   HWMON_T_INPUT | HWMON_T_LABEL,
>   			   HWMON_T_INPUT | HWMON_T_LABEL),
>   	HWMON_CHANNEL_INFO(fan,
> +			   HWMON_F_INPUT | HWMON_F_LABEL,
> +			   HWMON_F_INPUT | HWMON_F_LABEL,
> +			   HWMON_F_INPUT | HWMON_F_LABEL,
> +			   HWMON_F_INPUT | HWMON_F_LABEL,
> +			   HWMON_F_INPUT | HWMON_F_LABEL,
> +			   HWMON_F_INPUT | HWMON_F_LABEL,
>   			   HWMON_F_INPUT | HWMON_F_LABEL,
>   			   HWMON_F_INPUT | HWMON_F_LABEL),
>   	HWMON_CHANNEL_INFO(power,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
>   			   HWMON_P_INPUT | HWMON_P_LABEL,
>   			   HWMON_P_INPUT | HWMON_P_LABEL),
> +	HWMON_CHANNEL_INFO(pwm,
> +			   HWMON_PWM_INPUT,
> +			   HWMON_PWM_INPUT,
> +			   HWMON_PWM_INPUT,
> +			   HWMON_PWM_INPUT,
> +			   HWMON_PWM_INPUT,
> +			   HWMON_PWM_INPUT,
> +			   HWMON_PWM_INPUT,
> +			   HWMON_PWM_INPUT),
>   	HWMON_CHANNEL_INFO(in,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
>   			   HWMON_I_INPUT | HWMON_I_LABEL,
>   			   HWMON_I_INPUT | HWMON_I_LABEL,
>   			   HWMON_I_INPUT | HWMON_I_LABEL),
>   	HWMON_CHANNEL_INFO(curr,
> +			   HWMON_C_INPUT | HWMON_C_LABEL,
> +			   HWMON_C_INPUT | HWMON_C_LABEL,
> +			   HWMON_C_INPUT | HWMON_C_LABEL,
> +			   HWMON_C_INPUT | HWMON_C_LABEL,
> +			   HWMON_C_INPUT | HWMON_C_LABEL,
> +			   HWMON_C_INPUT | HWMON_C_LABEL,
>   			   HWMON_C_INPUT | HWMON_C_LABEL,
>   			   HWMON_C_INPUT | HWMON_C_LABEL),
>   	NULL
> @@ -326,6 +610,35 @@ static int aqc_raw_event(struct hid_device *hdev, struct hid_report *report, u8
>   				priv->temp_input[i] = sensor_value * 10;
>   		}
>   		break;
> +	case octo:
> +		priv->power_cycles = get_unaligned_be32(data + OCTO_POWER_CYCLES);
> +
> +		/* Fan speed and related readings */
> +		for (i = 0; i < OCTO_NUM_FANS; i++) {
> +			priv->speed_input[i] =
> +			    get_unaligned_be16(data + octo_sensor_fan_offsets[i] +
> +					       OCTO_FAN_SPEED_OFFSET);
> +			priv->power_input[i] =
> +			    get_unaligned_be16(data + octo_sensor_fan_offsets[i] +
> +					       OCTO_FAN_POWER_OFFSET) * 10000;
> +			priv->voltage_input[i] =
> +			    get_unaligned_be16(data + octo_sensor_fan_offsets[i] +
> +					       OCTO_FAN_VOLTAGE_OFFSET) * 10;
> +			priv->current_input[i] =
> +			    get_unaligned_be16(data + octo_sensor_fan_offsets[i] +
> +					       OCTO_FAN_CURRENT_OFFSET);
> +		}
> +
> +		/* Temperature sensor readings */
> +		for (i = 0; i < OCTO_NUM_SENSORS; i++) {
> +			sensor_value = get_unaligned_be16(data + OCTO_SENSOR_START +
> +							  i * OCTO_SENSOR_SIZE);
> +			if (sensor_value == OCTO_SENSOR_DISCONNECTED)
> +				priv->temp_input[i] = -ENODATA;
> +			else
> +				priv->temp_input[i] = sensor_value * 10;
> +		}
> +		break;
>   	default:
>   		break;
>   	}
> @@ -378,8 +691,13 @@ static void aqc_debugfs_init(struct aqc_data *priv)
>   	debugfs_create_file("serial_number", 0444, priv->debugfs, priv, &serial_number_fops);
>   	debugfs_create_file("firmware_version", 0444, priv->debugfs, priv, &firmware_version_fops);
>   
> -	if (priv->kind == d5next)
> +	switch (priv->kind) {
> +	case d5next:
> +	case octo:
>   		debugfs_create_file("power_cycles", 0444, priv->debugfs, priv, &power_cycles_fops);

Same as above.

> +	default:
> +		break;
> +	}
>   }
>   
>   #else
> @@ -419,9 +737,30 @@ static int aqc_probe(struct hid_device *hdev, const struct hid_device_id *id)
>   	switch (hdev->product) {
>   	case USB_PRODUCT_ID_D5NEXT:
>   		priv->kind = d5next;
> +
> +		priv->temp_label = label_d5next_temp;
> +		priv->speed_label = label_d5next_speeds;
> +		priv->power_label = label_d5next_power;
> +		priv->voltage_label = label_d5next_voltages;
> +		priv->current_label = label_d5next_current;
>   		break;
>   	case USB_PRODUCT_ID_FARBWERK360:
>   		priv->kind = farbwerk360;
> +
> +		priv->temp_label = label_temp_sensors;
> +		break;
> +	case USB_PRODUCT_ID_OCTO:
> +		priv->kind = octo;
> +		priv->buffer_size = OCTO_CTRL_REPORT_SIZE;
> +		priv->checksum_start = OCTO_CTRL_REPORT_CHECKSUM_START;
> +		priv->checksum_length = OCTO_CTRL_REPORT_CHECKSUM_LENGTH;
> +		priv->checksum_offset = OCTO_CTRL_REPORT_CHECKSUM_OFFSET;
> +
> +		priv->temp_label = label_temp_sensors;
> +		priv->speed_label = label_fan_speed;
> +		priv->power_label = label_fan_power;
> +		priv->voltage_label = label_fan_voltage;
> +		priv->current_label = label_fan_current;
>   		break;
>   	default:
>   		break;
> @@ -429,6 +768,12 @@ static int aqc_probe(struct hid_device *hdev, const struct hid_device_id *id)
>   
>   	priv->name = aqc_device_names[priv->kind];
>   
> +	priv->buffer = devm_kzalloc(&hdev->dev, priv->buffer_size, GFP_KERNEL);
> +	if (!priv->buffer)
> +		return -ENOMEM;
> +
> +	mutex_init(&priv->mutex);
> +
>   	priv->hwmon_dev = hwmon_device_register_with_info(&hdev->dev, priv->name, priv,
>   							  &aqc_chip_info, NULL);
>   
> @@ -462,6 +807,7 @@ static void aqc_remove(struct hid_device *hdev)
>   static const struct hid_device_id aqc_table[] = {
>   	{ HID_USB_DEVICE(USB_VENDOR_ID_AQUACOMPUTER, USB_PRODUCT_ID_D5NEXT) },
>   	{ HID_USB_DEVICE(USB_VENDOR_ID_AQUACOMPUTER, USB_PRODUCT_ID_FARBWERK360) },
> +	{ HID_USB_DEVICE(USB_VENDOR_ID_AQUACOMPUTER, USB_PRODUCT_ID_OCTO) },
>   	{ }
>   };
>