1 files changed, 428 insertions, 0 deletions
diff --git a/drivers/hwmon/gigabyte_waterforce.c b/drivers/hwmon/gigabyte_waterforce.c
new file mode 100644
index 000000000000..1799377fc2f1
--- /dev/null
+++ b/drivers/hwmon/gigabyte_waterforce.c
@@ -0,0 +1,428 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * hwmon driver for Gigabyte AORUS Waterforce AIO CPU coolers: X240, X280 and X360.
+ *
+ * Copyright 2023 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	"gigabyte_waterforce"
+
+#define USB_VENDOR_ID_GIGABYTE		0x1044
+#define USB_PRODUCT_ID_WATERFORCE	0x7a4d	/* Gigabyte AORUS WATERFORCE X240, X280 and X360 */
+
+#define STATUS_VALIDITY		(2 * 1000)	/* ms */
+#define MAX_REPORT_LENGTH	6144
+
+#define WATERFORCE_TEMP_SENSOR	0xD
+#define WATERFORCE_FAN_SPEED	0x02
+#define WATERFORCE_PUMP_SPEED	0x05
+#define WATERFORCE_FAN_DUTY	0x08
+#define WATERFORCE_PUMP_DUTY	0x09
+
+/* Control commands, inner offsets and lengths */
+static const u8 get_status_cmd[] = { 0x99, 0xDA };
+
+#define FIRMWARE_VER_START_OFFSET_1	2
+#define FIRMWARE_VER_START_OFFSET_2	3
+static const u8 get_firmware_ver_cmd[] = { 0x99, 0xD6 };
+
+/* Command lengths */
+#define GET_STATUS_CMD_LENGTH		2
+#define GET_FIRMWARE_VER_CMD_LENGTH	2
+
+static const char *const waterforce_temp_label[] = {
+	"Coolant temp"
+};
+
+static const char *const waterforce_speed_label[] = {
+	"Fan speed",
+	"Pump speed"
+};
+
+struct waterforce_data {
+	struct hid_device *hdev;
+	struct device *hwmon_dev;
+	struct dentry *debugfs;
+	/* For locking access to buffer */
+	struct mutex buffer_lock;
+	/* For queueing multiple readers */
+	struct mutex status_report_request_mutex;
+	/* For reinitializing the completion below */
+	spinlock_t status_report_request_lock;
+	struct completion status_report_received;
+	struct completion fw_version_processed;
+
+	/* Sensor data */
+	s32 temp_input[1];
+	u16 speed_input[2];	/* Fan and pump speed in RPM */
+	u8 duty_input[2];	/* Fan and pump duty in 0-100% */
+
+	u8 *buffer;
+	int firmware_version;
+	unsigned long updated;	/* jiffies */
+};
+
+static umode_t waterforce_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 0444;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+/* Writes the command to the device with the rest of the report filled with zeroes */
+static int waterforce_write_expanded(struct waterforce_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;
+}
+
+static int waterforce_get_status(struct waterforce_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;
+	}
+
+	/*
+	 * 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 priv->status_report_received
+	 * completion as done.
+	 */
+	spin_lock_bh(&priv->status_report_request_lock);
+	reinit_completion(&priv->status_report_received);
+	spin_unlock_bh(&priv->status_report_request_lock);
+
+	/* Send command for getting status */
+	ret = waterforce_write_expanded(priv, get_status_cmd, GET_STATUS_CMD_LENGTH);
+	if (ret < 0)
+		return ret;
+
+	ret = wait_for_completion_interruptible_timeout(&priv->status_report_received,
+							msecs_to_jiffies(STATUS_VALIDITY));
+	if (ret == 0)
+		ret = -ETIMEDOUT;
+
+unlock_and_return:
+	mutex_unlock(&priv->status_report_request_mutex);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int waterforce_read(struct device *dev, enum hwmon_sensor_types type,
+			   u32 attr, int channel, long *val)
+{
+	struct waterforce_data *priv = dev_get_drvdata(dev);
+	int ret = waterforce_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 = DIV_ROUND_CLOSEST(priv->duty_input[channel] * 255, 100);
+			break;
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+	default:
+		return -EOPNOTSUPP;	/* unreachable */
+	}
+
+	return 0;
+}
+
+static int waterforce_read_string(struct device *dev, enum hwmon_sensor_types type,
+				  u32 attr, int channel, const char **str)
+{
+	switch (type) {
+	case hwmon_temp:
+		*str = waterforce_temp_label[channel];
+		break;
+	case hwmon_fan:
+		*str = waterforce_speed_label[channel];
+		break;
+	default:
+		return -EOPNOTSUPP;	/* unreachable */
+	}
+
+	return 0;
+}
+
+static int waterforce_get_fw_ver(struct hid_device *hdev)
+{
+	struct waterforce_data *priv = hid_get_drvdata(hdev);
+	int ret;
+
+	ret = waterforce_write_expanded(priv, get_firmware_ver_cmd, GET_FIRMWARE_VER_CMD_LENGTH);
+	if (ret < 0)
+		return ret;
+
+	ret = wait_for_completion_interruptible_timeout(&priv->fw_version_processed,
+							msecs_to_jiffies(STATUS_VALIDITY));
+	if (ret == 0)
+		return -ETIMEDOUT;
+	else if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static const struct hwmon_ops waterforce_hwmon_ops = {
+	.is_visible = waterforce_is_visible,
+	.read = waterforce_read,
+	.read_string = waterforce_read_string
+};
+
+static const struct hwmon_channel_info *waterforce_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_CHANNEL_INFO(pwm,
+			   HWMON_PWM_INPUT,
+			   HWMON_PWM_INPUT),
+	NULL
+};
+
+static const struct hwmon_chip_info waterforce_chip_info = {
+	.ops = &waterforce_hwmon_ops,
+	.info = waterforce_info,
+};
+
+static int waterforce_raw_event(struct hid_device *hdev, struct hid_report *report, u8 *data,
+				int size)
+{
+	struct waterforce_data *priv = hid_get_drvdata(hdev);
+
+	if (data[0] == get_firmware_ver_cmd[0] && data[1] == get_firmware_ver_cmd[1]) {
+		/* Received a firmware version report */
+		priv->firmware_version =
+		    data[FIRMWARE_VER_START_OFFSET_1] * 10 + data[FIRMWARE_VER_START_OFFSET_2];
+
+		if (!completion_done(&priv->fw_version_processed))
+			complete_all(&priv->fw_version_processed);
+		return 0;
+	}
+
+	if (data[0] != get_status_cmd[0] || data[1] != get_status_cmd[1])
+		return 0;
+
+	priv->temp_input[0] = data[WATERFORCE_TEMP_SENSOR] * 1000;
+	priv->speed_input[0] = get_unaligned_le16(data + WATERFORCE_FAN_SPEED);
+	priv->speed_input[1] = get_unaligned_le16(data + WATERFORCE_PUMP_SPEED);
+	priv->duty_input[0] = data[WATERFORCE_FAN_DUTY];
+	priv->duty_input[1] = data[WATERFORCE_PUMP_DUTY];
+
+	if (!completion_done(&priv->status_report_received))
+		complete_all(&priv->status_report_received);
+
+	priv->updated = jiffies;
+
+	return 0;
+}
+
+static int firmware_version_show(struct seq_file *seqf, void *unused)
+{
+	struct waterforce_data *priv = seqf->private;
+
+	seq_printf(seqf, "%u\n", priv->firmware_version);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(firmware_version);
+
+static void waterforce_debugfs_init(struct waterforce_data *priv)
+{
+	char name[64];
+
+	if (!priv->firmware_version)
+		return;	/* There's nothing to show in debugfs */
+
+	scnprintf(name, sizeof(name), "%s-%s", DRIVER_NAME, dev_name(&priv->hdev->dev));
+
+	priv->debugfs = debugfs_create_dir(name, NULL);
+	debugfs_create_file("firmware_version", 0444, priv->debugfs, priv, &firmware_version_fops);
+}
+
+static int waterforce_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	struct waterforce_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 waterforce_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->status_report_received);
+	init_completion(&priv->fw_version_processed);
+
+	hid_device_io_start(hdev);
+	ret = waterforce_get_fw_ver(hdev);
+	if (ret < 0)
+		hid_warn(hdev, "fw version request failed with %d\n", ret);
+
+	priv->hwmon_dev = hwmon_device_register_with_info(&hdev->dev, "waterforce",
+							  priv, &waterforce_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;
+	}
+
+	waterforce_debugfs_init(priv);
+
+	return 0;
+
+fail_and_close:
+	hid_hw_close(hdev);
+fail_and_stop:
+	hid_hw_stop(hdev);
+	return ret;
+}
+
+static void waterforce_remove(struct hid_device *hdev)
+{
+	struct waterforce_data *priv = hid_get_drvdata(hdev);
+
+	debugfs_remove_recursive(priv->debugfs);
+	hwmon_device_unregister(priv->hwmon_dev);
+
+	hid_hw_close(hdev);
+	hid_hw_stop(hdev);
+}
+
+static const struct hid_device_id waterforce_table[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_GIGABYTE, USB_PRODUCT_ID_WATERFORCE) },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(hid, waterforce_table);
+
+static struct hid_driver waterforce_driver = {
+	.name = "waterforce",
+	.id_table = waterforce_table,
+	.probe = waterforce_probe,
+	.remove = waterforce_remove,
+	.raw_event = waterforce_raw_event,
+};
+
+static int __init waterforce_init(void)
+{
+	return hid_register_driver(&waterforce_driver);
+}
+
+static void __exit waterforce_exit(void)
+{
+	hid_unregister_driver(&waterforce_driver);
+}
+
+/* When compiled into the kernel, initialize after the HID bus */
+late_initcall(waterforce_init);
+module_exit(waterforce_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Aleksa Savic <savicaleksa83@gmail.com>");
+MODULE_DESCRIPTION("Hwmon driver for Gigabyte AORUS Waterforce AIO coolers");