hwmon: Add driver for ASUS ROG RYUJIN II 360 AIO cooler

This driver exposes hardware sensors of the ASUS ROG RYUJIN II 360
all-in-one CPU liquid cooler, which communicates through a proprietary
USB HID protocol. Report offsets were initially discovered in [1] by
Florian Freudiger.

Available sensors are pump, internal and external
(controller) fan speed in RPM, their duties in PWM, as well as
coolant temperature.

Attaching external fans to the controller is optional and allows them
to be controlled from the device. If not connected, the fan-related
sensors will report zeroes. The controller is a separate hardware unit
that comes bundled with the AIO and connects to it to allow fan control.

The addressable LCD screen is not supported in this
driver and should be controlled through userspace tools.

[1]: https://github.com/liquidctl/liquidctl/pull/653

Tested-by: Florian Freudiger <florian.freudiger@proton.me>
Signed-off-by: Aleksa Savic <savicaleksa83@gmail.com>
Link: https://lore.kernel.org/r/20240108094453.22986-1-savicaleksa83@gmail.com
[groeck: Add HID dependency]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

3 files changed, 620 insertions, 0 deletions

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 3904bb297d61..e4b24ad93961 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -301,6 +301,16 @@ config SENSORS_ASC7621
 	  This driver can also be built as a module. If so, the module
 	  will be called asc7621.
 
+config SENSORS_ASUS_ROG_RYUJIN
+	tristate "ASUS ROG RYUJIN II 360 hardware monitoring driver"
+	depends on HID
+	help
+	  If you say yes here you get support for the fans and sensors of
+	  the ASUS ROG RYUJIN II 360 AIO CPU liquid cooler.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called asus_rog_ryujin.
+
 config SENSORS_AXI_FAN_CONTROL
 	tristate "Analog Devices FAN Control HDL Core driver"
 	help
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 76e6dfef9f24..e3faee7be51a 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -55,6 +55,7 @@ obj-$(CONFIG_SENSORS_ARM_SCPI)	+= scpi-hwmon.o
 obj-$(CONFIG_SENSORS_AS370)	+= as370-hwmon.o
 obj-$(CONFIG_SENSORS_ASC7621)	+= asc7621.o
 obj-$(CONFIG_SENSORS_ASPEED)	+= aspeed-pwm-tacho.o
+obj-$(CONFIG_SENSORS_ASUS_ROG_RYUJIN)	+= asus_rog_ryujin.o
 obj-$(CONFIG_SENSORS_ATXP1)	+= atxp1.o
 obj-$(CONFIG_SENSORS_AXI_FAN_CONTROL) += axi-fan-control.o
 obj-$(CONFIG_SENSORS_BT1_PVT)	+= bt1-pvt.o
diff --git a/drivers/hwmon/asus_rog_ryujin.c b/drivers/hwmon/asus_rog_ryujin.c
new file mode 100644
index 000000000000..f8b20346a995
--- /dev/null
+++ b/drivers/hwmon/asus_rog_ryujin.c
@@ -0,0 +1,609 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * hwmon driver for Asus ROG Ryujin II 360 AIO cooler.
+ *
+ * Copyright 2024 Aleksa Savic <savicaleksa83@gmail.com>
+ */
+
+#include <linux/debugfs.h>
+#include <linux/hid.h>
+#include <linux/hwmon.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <asm/unaligned.h>
+
+#define DRIVER_NAME	"asus_rog_ryujin"
+
+#define USB_VENDOR_ID_ASUS_ROG		0x0b05
+#define USB_PRODUCT_ID_RYUJIN_AIO	0x1988	/* ASUS ROG RYUJIN II 360 */
+
+#define STATUS_VALIDITY		1500	/* ms */
+#define MAX_REPORT_LENGTH	65
+
+/* Cooler status report offsets */
+#define RYUJIN_TEMP_SENSOR_1		3
+#define RYUJIN_TEMP_SENSOR_2		4
+#define RYUJIN_PUMP_SPEED		5
+#define RYUJIN_INTERNAL_FAN_SPEED	7
+
+/* Cooler duty report offsets */
+#define RYUJIN_PUMP_DUTY		4
+#define RYUJIN_INTERNAL_FAN_DUTY	5
+
+/* Controller status (speeds) report offsets */
+#define RYUJIN_CONTROLLER_SPEED_1	5
+#define RYUJIN_CONTROLLER_SPEED_2	7
+#define RYUJIN_CONTROLLER_SPEED_3	9
+#define RYUJIN_CONTROLLER_SPEED_4	3
+
+/* Controller duty report offsets */
+#define RYUJIN_CONTROLLER_DUTY		4
+
+/* Control commands and their inner offsets */
+#define RYUJIN_CMD_PREFIX	0xEC
+
+static const u8 get_cooler_status_cmd[] = { RYUJIN_CMD_PREFIX, 0x99 };
+static const u8 get_cooler_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0x9A };
+static const u8 get_controller_speed_cmd[] = { RYUJIN_CMD_PREFIX, 0xA0 };
+static const u8 get_controller_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0xA1 };
+
+#define RYUJIN_SET_COOLER_PUMP_DUTY_OFFSET	3
+#define RYUJIN_SET_COOLER_FAN_DUTY_OFFSET	4
+static const u8 set_cooler_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0x1A, 0x00, 0x00, 0x00 };
+
+#define RYUJIN_SET_CONTROLLER_FAN_DUTY_OFFSET	4
+static const u8 set_controller_duty_cmd[] = { RYUJIN_CMD_PREFIX, 0x21, 0x00, 0x00, 0x00 };
+
+/* Command lengths */
+#define GET_CMD_LENGTH	2	/* Same length for all get commands */
+#define SET_CMD_LENGTH	5	/* Same length for all set commands */
+
+/* Command response headers */
+#define RYUJIN_GET_COOLER_STATUS_CMD_RESPONSE		0x19
+#define RYUJIN_GET_COOLER_DUTY_CMD_RESPONSE		0x1A
+#define RYUJIN_GET_CONTROLLER_SPEED_CMD_RESPONSE	0x20
+#define RYUJIN_GET_CONTROLLER_DUTY_CMD_RESPONSE		0x21
+
+static const char *const rog_ryujin_temp_label[] = {
+	"Coolant temp"
+};
+
+static const char *const rog_ryujin_speed_label[] = {
+	"Pump speed",
+	"Internal fan speed",
+	"Controller fan 1 speed",
+	"Controller fan 2 speed",
+	"Controller fan 3 speed",
+	"Controller fan 4 speed",
+};
+
+struct rog_ryujin_data {
+	struct hid_device *hdev;
+	struct device *hwmon_dev;
+	/* For locking access to buffer */
+	struct mutex buffer_lock;
+	/* For queueing multiple readers */
+	struct mutex status_report_request_mutex;
+	/* For reinitializing the completions below */
+	spinlock_t status_report_request_lock;
+	struct completion cooler_status_received;
+	struct completion controller_status_received;
+	struct completion cooler_duty_received;
+	struct completion controller_duty_received;
+	struct completion cooler_duty_set;
+	struct completion controller_duty_set;
+
+	/* Sensor data */
+	s32 temp_input[1];
+	u16 speed_input[6];	/* Pump, internal fan and four controller fan speeds in RPM */
+	u8 duty_input[3];	/* Pump, internal fan and controller fan duty in PWM */
+
+	u8 *buffer;
+	unsigned long updated;	/* jiffies */
+};
+
+static int rog_ryujin_percent_to_pwm(u16 val)
+{
+	return DIV_ROUND_CLOSEST(val * 255, 100);
+}
+
+static int rog_ryujin_pwm_to_percent(long val)
+{
+	return DIV_ROUND_CLOSEST(val * 100, 255);
+}
+
+static umode_t rog_ryujin_is_visible(const void *data,
+				     enum hwmon_sensor_types type, u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_label:
+		case hwmon_temp_input:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+	case hwmon_fan:
+		switch (attr) {
+		case hwmon_fan_label:
+		case hwmon_fan_input:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+			return 0644;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+/* Writes the command to the device with the rest of the report filled with zeroes */
+static int rog_ryujin_write_expanded(struct rog_ryujin_data *priv, const u8 *cmd, int cmd_length)
+{
+	int ret;
+
+	mutex_lock(&priv->buffer_lock);
+
+	memcpy_and_pad(priv->buffer, MAX_REPORT_LENGTH, cmd, cmd_length, 0x00);
+	ret = hid_hw_output_report(priv->hdev, priv->buffer, MAX_REPORT_LENGTH);
+
+	mutex_unlock(&priv->buffer_lock);
+	return ret;
+}
+
+/* Assumes priv->status_report_request_mutex is locked */
+static int rog_ryujin_execute_cmd(struct rog_ryujin_data *priv, const u8 *cmd, int cmd_length,
+				  struct completion *status_completion)
+{
+	int ret;
+
+	/*
+	 * Disable raw event parsing for a moment to safely reinitialize the
+	 * completion. Reinit is done because hidraw could have triggered
+	 * the raw event parsing and marked the passed in completion as done.
+	 */
+	spin_lock_bh(&priv->status_report_request_lock);
+	reinit_completion(status_completion);
+	spin_unlock_bh(&priv->status_report_request_lock);
+
+	/* Send command for getting data */
+	ret = rog_ryujin_write_expanded(priv, cmd, cmd_length);
+	if (ret < 0)
+		return ret;
+
+	ret = wait_for_completion_interruptible_timeout(status_completion,
+							msecs_to_jiffies(STATUS_VALIDITY));
+	if (ret == 0)
+		return -ETIMEDOUT;
+	else if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int rog_ryujin_get_status(struct rog_ryujin_data *priv)
+{
+	int ret = mutex_lock_interruptible(&priv->status_report_request_mutex);
+
+	if (ret < 0)
+		return ret;
+
+	if (!time_after(jiffies, priv->updated + msecs_to_jiffies(STATUS_VALIDITY))) {
+		/* Data is up to date */
+		goto unlock_and_return;
+	}
+
+	/* Retrieve cooler status */
+	ret =
+	    rog_ryujin_execute_cmd(priv, get_cooler_status_cmd, GET_CMD_LENGTH,
+				   &priv->cooler_status_received);
+	if (ret < 0)
+		goto unlock_and_return;
+
+	/* Retrieve controller status (speeds) */
+	ret =
+	    rog_ryujin_execute_cmd(priv, get_controller_speed_cmd, GET_CMD_LENGTH,
+				   &priv->controller_status_received);
+	if (ret < 0)
+		goto unlock_and_return;
+
+	/* Retrieve cooler duty */
+	ret =
+	    rog_ryujin_execute_cmd(priv, get_cooler_duty_cmd, GET_CMD_LENGTH,
+				   &priv->cooler_duty_received);
+	if (ret < 0)
+		goto unlock_and_return;
+
+	/* Retrieve controller duty */
+	ret =
+	    rog_ryujin_execute_cmd(priv, get_controller_duty_cmd, GET_CMD_LENGTH,
+				   &priv->controller_duty_received);
+	if (ret < 0)
+		goto unlock_and_return;
+
+	priv->updated = jiffies;
+
+unlock_and_return:
+	mutex_unlock(&priv->status_report_request_mutex);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int rog_ryujin_read(struct device *dev, enum hwmon_sensor_types type,
+			   u32 attr, int channel, long *val)
+{
+	struct rog_ryujin_data *priv = dev_get_drvdata(dev);
+	int ret = rog_ryujin_get_status(priv);
+
+	if (ret < 0)
+		return ret;
+
+	switch (type) {
+	case hwmon_temp:
+		*val = priv->temp_input[channel];
+		break;
+	case hwmon_fan:
+		*val = priv->speed_input[channel];
+		break;
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+			*val = priv->duty_input[channel];
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;	/* unreachable */
+	}
+
+	return 0;
+}
+
+static int rog_ryujin_read_string(struct device *dev, enum hwmon_sensor_types type,
+				  u32 attr, int channel, const char **str)
+{
+	switch (type) {
+	case hwmon_temp:
+		*str = rog_ryujin_temp_label[channel];
+		break;
+	case hwmon_fan:
+		*str = rog_ryujin_speed_label[channel];
+		break;
+	default:
+		return -EOPNOTSUPP;	/* unreachable */
+	}
+
+	return 0;
+}
+
+static int rog_ryujin_write_fixed_duty(struct rog_ryujin_data *priv, int channel, int val)
+{
+	u8 set_cmd[SET_CMD_LENGTH];
+	int ret;
+
+	if (channel < 2) {
+		/*
+		 * Retrieve cooler duty since both pump and internal fan are set
+		 * together, then write back with one of them modified.
+		 */
+		ret = mutex_lock_interruptible(&priv->status_report_request_mutex);
+		if (ret < 0)
+			return ret;
+		ret =
+		    rog_ryujin_execute_cmd(priv, get_cooler_duty_cmd, GET_CMD_LENGTH,
+					   &priv->cooler_duty_received);
+		if (ret < 0)
+			goto unlock_and_return;
+
+		memcpy(set_cmd, set_cooler_duty_cmd, SET_CMD_LENGTH);
+
+		/* Cooler duties are set as 0-100% */
+		val = rog_ryujin_pwm_to_percent(val);
+
+		if (channel == 0) {
+			/* Cooler pump duty */
+			set_cmd[RYUJIN_SET_COOLER_PUMP_DUTY_OFFSET] = val;
+			set_cmd[RYUJIN_SET_COOLER_FAN_DUTY_OFFSET] =
+			    rog_ryujin_pwm_to_percent(priv->duty_input[1]);
+		} else if (channel == 1) {
+			/* Cooler internal fan duty */
+			set_cmd[RYUJIN_SET_COOLER_PUMP_DUTY_OFFSET] =
+			    rog_ryujin_pwm_to_percent(priv->duty_input[0]);
+			set_cmd[RYUJIN_SET_COOLER_FAN_DUTY_OFFSET] = val;
+		}
+
+		ret = rog_ryujin_execute_cmd(priv, set_cmd, SET_CMD_LENGTH, &priv->cooler_duty_set);
+unlock_and_return:
+		mutex_unlock(&priv->status_report_request_mutex);
+		if (ret < 0)
+			return ret;
+	} else {
+		/*
+		 * Controller fan duty (channel == 2). No need to retrieve current
+		 * duty, so just send the command.
+		 */
+		memcpy(set_cmd, set_controller_duty_cmd, SET_CMD_LENGTH);
+		set_cmd[RYUJIN_SET_CONTROLLER_FAN_DUTY_OFFSET] = val;
+
+		ret =
+		    rog_ryujin_execute_cmd(priv, set_cmd, SET_CMD_LENGTH,
+					   &priv->controller_duty_set);
+		if (ret < 0)
+			return ret;
+	}
+
+	/* Lock onto this value until next refresh cycle */
+	priv->duty_input[channel] = val;
+
+	return 0;
+}
+
+static int rog_ryujin_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
+			    long val)
+{
+	struct rog_ryujin_data *priv = dev_get_drvdata(dev);
+	int ret;
+
+	switch (type) {
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+			if (val < 0 || val > 255)
+				return -EINVAL;
+
+			ret = rog_ryujin_write_fixed_duty(priv, channel, val);
+			if (ret < 0)
+				return ret;
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static const struct hwmon_ops rog_ryujin_hwmon_ops = {
+	.is_visible = rog_ryujin_is_visible,
+	.read = rog_ryujin_read,
+	.read_string = rog_ryujin_read_string,
+	.write = rog_ryujin_write
+};
+
+static const struct hwmon_channel_info *rog_ryujin_info[] = {
+	HWMON_CHANNEL_INFO(temp,
+			   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_CHANNEL_INFO(pwm,
+			   HWMON_PWM_INPUT,
+			   HWMON_PWM_INPUT,
+			   HWMON_PWM_INPUT),
+	NULL
+};
+
+static const struct hwmon_chip_info rog_ryujin_chip_info = {
+	.ops = &rog_ryujin_hwmon_ops,
+	.info = rog_ryujin_info,
+};
+
+static int rog_ryujin_raw_event(struct hid_device *hdev, struct hid_report *report, u8 *data,
+				int size)
+{
+	struct rog_ryujin_data *priv = hid_get_drvdata(hdev);
+
+	if (data[0] != RYUJIN_CMD_PREFIX)
+		return 0;
+
+	if (data[1] == RYUJIN_GET_COOLER_STATUS_CMD_RESPONSE) {
+		/* Received coolant temp and speeds of pump and internal fan */
+		priv->temp_input[0] =
+		    data[RYUJIN_TEMP_SENSOR_1] * 1000 + data[RYUJIN_TEMP_SENSOR_2] * 100;
+		priv->speed_input[0] = get_unaligned_le16(data + RYUJIN_PUMP_SPEED);
+		priv->speed_input[1] = get_unaligned_le16(data + RYUJIN_INTERNAL_FAN_SPEED);
+
+		if (!completion_done(&priv->cooler_status_received))
+			complete_all(&priv->cooler_status_received);
+	} else if (data[1] == RYUJIN_GET_CONTROLLER_SPEED_CMD_RESPONSE) {
+		/* Received speeds of four fans attached to the controller */
+		priv->speed_input[2] = get_unaligned_le16(data + RYUJIN_CONTROLLER_SPEED_1);
+		priv->speed_input[3] = get_unaligned_le16(data + RYUJIN_CONTROLLER_SPEED_2);
+		priv->speed_input[4] = get_unaligned_le16(data + RYUJIN_CONTROLLER_SPEED_3);
+		priv->speed_input[5] = get_unaligned_le16(data + RYUJIN_CONTROLLER_SPEED_4);
+
+		if (!completion_done(&priv->controller_status_received))
+			complete_all(&priv->controller_status_received);
+	} else if (data[1] == RYUJIN_GET_COOLER_DUTY_CMD_RESPONSE) {
+		/* Received report for pump and internal fan duties (in %) */
+		if (data[RYUJIN_PUMP_DUTY] == 0 && data[RYUJIN_INTERNAL_FAN_DUTY] == 0) {
+			/*
+			 * We received a report with zeroes for duty in both places.
+			 * The device returns this as a confirmation that setting values
+			 * is successful. If we initiated a write, mark it as complete.
+			 */
+			if (!completion_done(&priv->cooler_duty_set))
+				complete_all(&priv->cooler_duty_set);
+			else if (!completion_done(&priv->cooler_duty_received))
+				/*
+				 * We didn't initiate a write, but received both zeroes.
+				 * This means that either both duties are actually zero,
+				 * or that we received a success report caused by userspace.
+				 * We're expecting a report, so parse it.
+				 */
+				goto read_cooler_duty;
+			return 0;
+		}
+read_cooler_duty:
+		priv->duty_input[0] = rog_ryujin_percent_to_pwm(data[RYUJIN_PUMP_DUTY]);
+		priv->duty_input[1] = rog_ryujin_percent_to_pwm(data[RYUJIN_INTERNAL_FAN_DUTY]);
+
+		if (!completion_done(&priv->cooler_duty_received))
+			complete_all(&priv->cooler_duty_received);
+	} else if (data[1] == RYUJIN_GET_CONTROLLER_DUTY_CMD_RESPONSE) {
+		/* Received report for controller duty for fans (in PWM) */
+		if (data[RYUJIN_CONTROLLER_DUTY] == 0) {
+			/*
+			 * We received a report with a zero for duty. The device returns this as
+			 * a confirmation that setting the controller duty value was successful.
+			 * If we initiated a write, mark it as complete.
+			 */
+			if (!completion_done(&priv->controller_duty_set))
+				complete_all(&priv->controller_duty_set);
+			else if (!completion_done(&priv->controller_duty_received))
+				/*
+				 * We didn't initiate a write, but received a zero for duty.
+				 * This means that either the duty is actually zero, or that
+				 * we received a success report caused by userspace.
+				 * We're expecting a report, so parse it.
+				 */
+				goto read_controller_duty;
+			return 0;
+		}
+read_controller_duty:
+		priv->duty_input[2] = data[RYUJIN_CONTROLLER_DUTY];
+
+		if (!completion_done(&priv->controller_duty_received))
+			complete_all(&priv->controller_duty_received);
+	}
+
+	return 0;
+}
+
+static int rog_ryujin_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	struct rog_ryujin_data *priv;
+	int ret;
+
+	priv = devm_kzalloc(&hdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->hdev = hdev;
+	hid_set_drvdata(hdev, priv);
+
+	/*
+	 * Initialize priv->updated to STATUS_VALIDITY seconds in the past, making
+	 * the initial empty data invalid for rog_ryujin_read() without the need for
+	 * a special case there.
+	 */
+	priv->updated = jiffies - msecs_to_jiffies(STATUS_VALIDITY);
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "hid parse failed with %d\n", ret);
+		return ret;
+	}
+
+	/* Enable hidraw so existing user-space tools can continue to work */
+	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
+	if (ret) {
+		hid_err(hdev, "hid hw start failed with %d\n", ret);
+		return ret;
+	}
+
+	ret = hid_hw_open(hdev);
+	if (ret) {
+		hid_err(hdev, "hid hw open failed with %d\n", ret);
+		goto fail_and_stop;
+	}
+
+	priv->buffer = devm_kzalloc(&hdev->dev, MAX_REPORT_LENGTH, GFP_KERNEL);
+	if (!priv->buffer) {
+		ret = -ENOMEM;
+		goto fail_and_close;
+	}
+
+	mutex_init(&priv->status_report_request_mutex);
+	mutex_init(&priv->buffer_lock);
+	spin_lock_init(&priv->status_report_request_lock);
+	init_completion(&priv->cooler_status_received);
+	init_completion(&priv->controller_status_received);
+	init_completion(&priv->cooler_duty_received);
+	init_completion(&priv->controller_duty_received);
+	init_completion(&priv->cooler_duty_set);
+	init_completion(&priv->controller_duty_set);
+
+	priv->hwmon_dev = hwmon_device_register_with_info(&hdev->dev, "rog_ryujin",
+							  priv, &rog_ryujin_chip_info, NULL);
+	if (IS_ERR(priv->hwmon_dev)) {
+		ret = PTR_ERR(priv->hwmon_dev);
+		hid_err(hdev, "hwmon registration failed with %d\n", ret);
+		goto fail_and_close;
+	}
+
+	return 0;
+
+fail_and_close:
+	hid_hw_close(hdev);
+fail_and_stop:
+	hid_hw_stop(hdev);
+	return ret;
+}
+
+static void rog_ryujin_remove(struct hid_device *hdev)
+{
+	struct rog_ryujin_data *priv = hid_get_drvdata(hdev);
+
+	hwmon_device_unregister(priv->hwmon_dev);
+
+	hid_hw_close(hdev);
+	hid_hw_stop(hdev);
+}
+
+static const struct hid_device_id rog_ryujin_table[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_ASUS_ROG, USB_PRODUCT_ID_RYUJIN_AIO) },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(hid, rog_ryujin_table);
+
+static struct hid_driver rog_ryujin_driver = {
+	.name = "rog_ryujin",
+	.id_table = rog_ryujin_table,
+	.probe = rog_ryujin_probe,
+	.remove = rog_ryujin_remove,
+	.raw_event = rog_ryujin_raw_event,
+};
+
+static int __init rog_ryujin_init(void)
+{
+	return hid_register_driver(&rog_ryujin_driver);
+}
+
+static void __exit rog_ryujin_exit(void)
+{
+	hid_unregister_driver(&rog_ryujin_driver);
+}
+
+/* When compiled into the kernel, initialize after the HID bus */
+late_initcall(rog_ryujin_init);
+module_exit(rog_ryujin_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Aleksa Savic <savicaleksa83@gmail.com>");
+MODULE_DESCRIPTION("Hwmon driver for Asus ROG Ryujin II 360 AIO cooler");