Quelle  gigabyte_waterforce.c   Sprache: C

// 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 <linux/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)
  goto unlock_and_return;

 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];

 spin_lock(&priv->status_report_request_lock);
 if (!completion_done(&priv->status_report_received))
  complete_all(&priv->status_report_received);
 spin_unlock(&priv->status_report_request_lock);

 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 ");
MODULE_DESCRIPTION("Hwmon driver for Gigabyte AORUS Waterforce AIO coolers");