hwmon: (asus_wmi_sensors) Support X370 Asus WMI.
authorDenis Pauk <pauk.denis@gmail.com>
Tue, 16 Nov 2021 20:57:44 +0000 (22:57 +0200)
committerGuenter Roeck <linux@roeck-us.net>
Sun, 26 Dec 2021 23:02:05 +0000 (15:02 -0800)
Provides a Linux kernel module "asus_wmi_sensors" that provides sensor
readouts via ASUS' WMI interface present in the UEFI of
X370/X470/B450/X399 Ryzen motherboards.

Supported motherboards:
* ROG CROSSHAIR VI HERO,
* PRIME X399-A,
* PRIME X470-PRO,
* ROG CROSSHAIR VI EXTREME,
* ROG CROSSHAIR VI HERO (WI-FI AC),
* ROG CROSSHAIR VII HERO,
* ROG CROSSHAIR VII HERO (WI-FI),
* ROG STRIX B450-E GAMING,
* ROG STRIX B450-F GAMING,
* ROG STRIX B450-I GAMING,
* ROG STRIX X399-E GAMING,
* ROG STRIX X470-F GAMING,
* ROG STRIX X470-I GAMING,
* ROG ZENITH EXTREME,
* ROG ZENITH EXTREME ALPHA.

Co-developed-by: Ed Brindley <kernel@maidavale.org>
Signed-off-by: Ed Brindley <kernel@maidavale.org>
Signed-off-by: Denis Pauk <pauk.denis@gmail.com>
[groeck: Squashed:
 "hwmon: Fix warnings in asus_wmi_sensors.rst documetation."]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Documentation/hwmon/asus_wmi_sensors.rst [new file with mode: 0644]
Documentation/hwmon/index.rst
MAINTAINERS
drivers/hwmon/Kconfig
drivers/hwmon/Makefile
drivers/hwmon/asus_wmi_sensors.c [new file with mode: 0644]

diff --git a/Documentation/hwmon/asus_wmi_sensors.rst b/Documentation/hwmon/asus_wmi_sensors.rst
new file mode 100644 (file)
index 0000000..8f2096c
--- /dev/null
@@ -0,0 +1,78 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+Kernel driver asus_wmi_sensors
+=================================
+
+Supported boards:
+ * PRIME X399-A,
+ * PRIME X470-PRO,
+ * ROG CROSSHAIR VI EXTREME,
+ * ROG CROSSHAIR VI HERO,
+ * ROG CROSSHAIR VI HERO (WI-FI AC),
+ * ROG CROSSHAIR VII HERO,
+ * ROG CROSSHAIR VII HERO (WI-FI),
+ * ROG STRIX B450-E GAMING,
+ * ROG STRIX B450-F GAMING,
+ * ROG STRIX B450-I GAMING,
+ * ROG STRIX X399-E GAMING,
+ * ROG STRIX X470-F GAMING,
+ * ROG STRIX X470-I GAMING,
+ * ROG ZENITH EXTREME,
+ * ROG ZENITH EXTREME ALPHA.
+
+Authors:
+    - Ed Brindley <kernel@maidavale.org>
+
+Description:
+------------
+ASUS mainboards publish hardware monitoring information via WMI interface.
+
+ASUS WMI interface provides a methods to get list of sensors and values of
+such, which is utilized by this driver to publish those sensor readings to the
+HWMON system.
+
+The driver is aware of and reads the following sensors:
+ * CPU Core Voltage,
+ * CPU SOC Voltage,
+ * DRAM Voltage,
+ * VDDP Voltage,
+ * 1.8V PLL Voltage,
+ * +12V Voltage,
+ * +5V Voltage,
+ * 3VSB Voltage,
+ * VBAT Voltage,
+ * AVCC3 Voltage,
+ * SB 1.05V Voltage,
+ * CPU Core Voltage,
+ * CPU SOC Voltage,
+ * DRAM Voltage,
+ * CPU Fan RPM,
+ * Chassis Fan 1 RPM,
+ * Chassis Fan 2 RPM,
+ * Chassis Fan 3 RPM,
+ * HAMP Fan RPM,
+ * Water Pump RPM,
+ * CPU OPT RPM,
+ * Water Flow RPM,
+ * AIO Pump RPM,
+ * CPU Temperature,
+ * CPU Socket Temperature,
+ * Motherboard Temperature,
+ * Chipset Temperature,
+ * Tsensor 1 Temperature,
+ * CPU VRM Temperature,
+ * Water In,
+ * Water Out,
+ * CPU VRM Output Current.
+
+Known Issues:
+ * The WMI implementation in some of Asus' BIOSes is buggy. This can result in
+   fans stopping, fans getting stuck at max speed, or temperature readouts
+   getting stuck. This is not an issue with the driver, but the BIOS. The Prime
+   X470 Pro seems particularly bad for this. The more frequently the WMI
+   interface is polled the greater the potential for this to happen. Until you
+   have subjected your computer to an extended soak test while polling the
+   sensors frequently, don't leave you computer unattended. Upgrading to new
+   BIOS version with method version greater than or equal to two should
+   rectify the issue.
+ * A few boards report 12v voltages to be ~10v.
index 3e196ea..9c9361d 100644 (file)
@@ -44,6 +44,7 @@ Hardware Monitoring Kernel Drivers
    asc7621
    aspeed-pwm-tacho
    asus_wmi_ec_sensors
+   asus_wmi_sensors
    bcm54140
    bel-pfe
    bpa-rs600
index 6b386f9..979195f 100644 (file)
@@ -2998,6 +2998,13 @@ W:       http://acpi4asus.sf.net
 F:     drivers/platform/x86/asus*.c
 F:     drivers/platform/x86/eeepc*.c
 
+ASUS WMI HARDWARE MONITOR DRIVER
+M:     Ed Brindley <kernel@maidavale.org>
+M:     Denis Pauk <pauk.denis@gmail.com>
+L:     linux-hwmon@vger.kernel.org
+S:     Maintained
+F:     drivers/hwmon/asus_wmi_sensors.c
+
 ASUS WMI EC HARDWARE MONITOR DRIVER
 M:     Eugene Shalygin <eugene.shalygin@gmail.com>
 M:     Denis Pauk <pauk.denis@gmail.com>
index 81f5e2d..44886bf 100644 (file)
@@ -2228,6 +2228,18 @@ config SENSORS_ATK0110
          This driver can also be built as a module. If so, the module
          will be called asus_atk0110.
 
+config SENSORS_ASUS_WMI
+       tristate "ASUS WMI X370/X470/B450/X399"
+       depends on ACPI_WMI
+       help
+         If you say yes here you get support for the ACPI hardware monitoring
+         interface found in X370/X470/B450/X399 ASUS motherboards. This driver
+         will provide readings of fans, voltages and temperatures through the system
+         firmware.
+
+         This driver can also be built as a module. If so, the module
+         will be called asus_wmi_sensors.
+
 config SENSORS_ASUS_WMI_EC
        tristate "ASUS WMI B550/X570"
        depends on ACPI_WMI
index 821345e..3a1551b 100644 (file)
@@ -9,6 +9,7 @@ obj-$(CONFIG_HWMON_VID)         += hwmon-vid.o
 # APCI drivers
 obj-$(CONFIG_SENSORS_ACPI_POWER) += acpi_power_meter.o
 obj-$(CONFIG_SENSORS_ATK0110)  += asus_atk0110.o
+obj-$(CONFIG_SENSORS_ASUS_WMI) += asus_wmi_sensors.o
 obj-$(CONFIG_SENSORS_ASUS_WMI_EC)      += asus_wmi_ec_sensors.o
 
 # Native drivers
diff --git a/drivers/hwmon/asus_wmi_sensors.c b/drivers/hwmon/asus_wmi_sensors.c
new file mode 100644 (file)
index 0000000..67af15d
--- /dev/null
@@ -0,0 +1,664 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * HWMON driver for ASUS motherboards that provides sensor readouts via WMI
+ * interface present in the UEFI of the X370/X470/B450/X399 Ryzen motherboards.
+ *
+ * Copyright (C) 2018-2019 Ed Brindley <kernel@maidavale.org>
+ *
+ * WMI interface provides:
+ * - CPU Core Voltage,
+ * - CPU SOC Voltage,
+ * - DRAM Voltage,
+ * - VDDP Voltage,
+ * - 1.8V PLL Voltage,
+ * - +12V Voltage,
+ * - +5V Voltage,
+ * - 3VSB Voltage,
+ * - VBAT Voltage,
+ * - AVCC3 Voltage,
+ * - SB 1.05V Voltage,
+ * - CPU Core Voltage,
+ * - CPU SOC Voltage,
+ * - DRAM Voltage,
+ * - CPU Fan RPM,
+ * - Chassis Fan 1 RPM,
+ * - Chassis Fan 2 RPM,
+ * - Chassis Fan 3 RPM,
+ * - HAMP Fan RPM,
+ * - Water Pump RPM,
+ * - CPU OPT RPM,
+ * - Water Flow RPM,
+ * - AIO Pump RPM,
+ * - CPU Temperature,
+ * - CPU Socket Temperature,
+ * - Motherboard Temperature,
+ * - Chipset Temperature,
+ * - Tsensor 1 Temperature,
+ * - CPU VRM Temperature,
+ * - Water In,
+ * - Water Out,
+ * - CPU VRM Output Current.
+ */
+
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/hwmon.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/units.h>
+#include <linux/wmi.h>
+
+#define ASUSWMI_MONITORING_GUID                "466747A0-70EC-11DE-8A39-0800200C9A66"
+#define ASUSWMI_METHODID_GET_VALUE     0x52574543 /* RWEC */
+#define ASUSWMI_METHODID_UPDATE_BUFFER 0x51574543 /* QWEC */
+#define ASUSWMI_METHODID_GET_INFO      0x50574543 /* PWEC */
+#define ASUSWMI_METHODID_GET_NUMBER    0x50574572 /* PWEr */
+#define ASUSWMI_METHODID_GET_VERSION   0x50574574 /* PWEt */
+
+#define ASUS_WMI_MAX_STR_SIZE          32
+
+#define DMI_EXACT_MATCH_ASUS_BOARD_NAME(name) {                                        \
+       .matches = {                                                            \
+               DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "ASUSTeK COMPUTER INC."),     \
+               DMI_EXACT_MATCH(DMI_BOARD_NAME, name),                          \
+       },                                                                      \
+}
+
+static const struct dmi_system_id asus_wmi_dmi_table[] = {
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("PRIME X399-A"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("PRIME X470-PRO"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VI EXTREME"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VI HERO"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VI HERO (WI-FI AC)"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VII HERO"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG CROSSHAIR VII HERO (WI-FI)"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX B450-E GAMING"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX B450-F GAMING"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX B450-I GAMING"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX X399-E GAMING"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX X470-F GAMING"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG STRIX X470-I GAMING"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG ZENITH EXTREME"),
+       DMI_EXACT_MATCH_ASUS_BOARD_NAME("ROG ZENITH EXTREME ALPHA"),
+       {}
+};
+MODULE_DEVICE_TABLE(dmi, asus_wmi_dmi_table);
+
+enum asus_wmi_sensor_class {
+       VOLTAGE         = 0x0,
+       TEMPERATURE_C   = 0x1,
+       FAN_RPM         = 0x2,
+       CURRENT         = 0x3,
+       WATER_FLOW      = 0x4,
+};
+
+enum asus_wmi_location {
+       CPU             = 0x0,
+       CPU_SOC         = 0x1,
+       DRAM            = 0x2,
+       MOTHERBOARD     = 0x3,
+       CHIPSET         = 0x4,
+       AUX             = 0x5,
+       VRM             = 0x6,
+       COOLER          = 0x7
+};
+
+enum asus_wmi_type {
+       SIGNED_INT      = 0x0,
+       UNSIGNED_INT    = 0x1,
+       SCALED          = 0x3,
+};
+
+enum asus_wmi_source {
+       SIO             = 0x1,
+       EC              = 0x2
+};
+
+static enum hwmon_sensor_types asus_data_types[] = {
+       [VOLTAGE]       = hwmon_in,
+       [TEMPERATURE_C] = hwmon_temp,
+       [FAN_RPM]       = hwmon_fan,
+       [CURRENT]       = hwmon_curr,
+       [WATER_FLOW]    = hwmon_fan,
+};
+
+static u32 hwmon_attributes[] = {
+       [hwmon_chip]    = HWMON_C_REGISTER_TZ,
+       [hwmon_temp]    = HWMON_T_INPUT | HWMON_T_LABEL,
+       [hwmon_in]      = HWMON_I_INPUT | HWMON_I_LABEL,
+       [hwmon_curr]    = HWMON_C_INPUT | HWMON_C_LABEL,
+       [hwmon_fan]     = HWMON_F_INPUT | HWMON_F_LABEL,
+};
+
+/**
+ * struct asus_wmi_sensor_info - sensor info.
+ * @id: sensor id.
+ * @data_type: sensor class e.g. voltage, temp etc.
+ * @location: sensor location.
+ * @name: sensor name.
+ * @source: sensor source.
+ * @type: sensor type signed, unsigned etc.
+ * @cached_value: cached sensor value.
+ */
+struct asus_wmi_sensor_info {
+       u32 id;
+       int data_type;
+       int location;
+       char name[ASUS_WMI_MAX_STR_SIZE];
+       int source;
+       int type;
+       long cached_value;
+};
+
+struct asus_wmi_wmi_info {
+       unsigned long source_last_updated[3];   /* in jiffies */
+       int sensor_count;
+
+       const struct asus_wmi_sensor_info **info[hwmon_max];
+       struct asus_wmi_sensor_info **info_by_id;
+};
+
+struct asus_wmi_sensors {
+       struct asus_wmi_wmi_info wmi;
+       /* lock access to internal cache */
+       struct mutex lock;
+};
+
+/*
+ * Universal method for calling WMI method
+ */
+static int asus_wmi_call_method(u32 method_id, u32 *args, struct acpi_buffer *output)
+{
+       struct acpi_buffer input = {(acpi_size) sizeof(*args), args };
+       acpi_status status;
+
+       status = wmi_evaluate_method(ASUSWMI_MONITORING_GUID, 0,
+                                    method_id, &input, output);
+       if (ACPI_FAILURE(status))
+               return -EIO;
+
+       return 0;
+}
+
+/*
+ * Gets the version of the ASUS sensors interface implemented
+ */
+static int asus_wmi_get_version(u32 *version)
+{
+       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+       u32 args[] = {0, 0, 0};
+       union acpi_object *obj;
+       int err;
+
+       err = asus_wmi_call_method(ASUSWMI_METHODID_GET_VERSION, args, &output);
+       if (err)
+               return err;
+
+       obj = output.pointer;
+       if (!obj)
+               return -EIO;
+
+       if (obj->type != ACPI_TYPE_INTEGER) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       err = 0;
+       *version = obj->integer.value;
+
+out_free_obj:
+       ACPI_FREE(obj);
+       return err;
+}
+
+/*
+ * Gets the number of sensor items
+ */
+static int asus_wmi_get_item_count(u32 *count)
+{
+       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+       u32 args[] = {0, 0, 0};
+       union acpi_object *obj;
+       int err;
+
+       err = asus_wmi_call_method(ASUSWMI_METHODID_GET_NUMBER, args, &output);
+       if (err)
+               return err;
+
+       obj = output.pointer;
+       if (!obj)
+               return -EIO;
+
+       if (obj->type != ACPI_TYPE_INTEGER) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       err = 0;
+       *count = obj->integer.value;
+
+out_free_obj:
+       ACPI_FREE(obj);
+       return err;
+}
+
+static int asus_wmi_hwmon_add_chan_info(struct hwmon_channel_info *asus_wmi_hwmon_chan,
+                                       struct device *dev, int num,
+                                       enum hwmon_sensor_types type, u32 config)
+{
+       u32 *cfg;
+
+       cfg = devm_kcalloc(dev, num + 1, sizeof(*cfg), GFP_KERNEL);
+       if (!cfg)
+               return -ENOMEM;
+
+       asus_wmi_hwmon_chan->type = type;
+       asus_wmi_hwmon_chan->config = cfg;
+       memset32(cfg, config, num);
+
+       return 0;
+}
+
+/*
+ * For a given sensor item returns details e.g. type (voltage/temperature/fan speed etc), bank etc
+ */
+static int asus_wmi_sensor_info(int index, struct asus_wmi_sensor_info *s)
+{
+       union acpi_object name_obj, data_type_obj, location_obj, source_obj, type_obj;
+       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+       u32 args[] = {index, 0};
+       union acpi_object *obj;
+       int err;
+
+       err = asus_wmi_call_method(ASUSWMI_METHODID_GET_INFO, args, &output);
+       if (err)
+               return err;
+
+       s->id = index;
+
+       obj = output.pointer;
+       if (!obj)
+               return -EIO;
+
+       if (obj->type != ACPI_TYPE_PACKAGE) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       if (obj->package.count != 5) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       name_obj = obj->package.elements[0];
+       if (name_obj.type != ACPI_TYPE_STRING) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       strncpy(s->name, name_obj.string.pointer, sizeof(s->name) - 1);
+
+       data_type_obj = obj->package.elements[1];
+       if (data_type_obj.type != ACPI_TYPE_INTEGER) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       s->data_type = data_type_obj.integer.value;
+
+       location_obj = obj->package.elements[2];
+       if (location_obj.type != ACPI_TYPE_INTEGER) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       s->location = location_obj.integer.value;
+
+       source_obj = obj->package.elements[3];
+       if (source_obj.type != ACPI_TYPE_INTEGER) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       s->source = source_obj.integer.value;
+
+       type_obj = obj->package.elements[4];
+       if (type_obj.type != ACPI_TYPE_INTEGER) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       err = 0;
+       s->type = type_obj.integer.value;
+
+out_free_obj:
+       ACPI_FREE(obj);
+       return err;
+}
+
+static int asus_wmi_update_buffer(int source)
+{
+       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+       u32 args[] = {source, 0};
+
+       return asus_wmi_call_method(ASUSWMI_METHODID_UPDATE_BUFFER, args, &output);
+}
+
+static int asus_wmi_get_sensor_value(u8 index, long *value)
+{
+       struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+       u32 args[] = {index, 0};
+       union acpi_object *obj;
+       int err;
+
+       err = asus_wmi_call_method(ASUSWMI_METHODID_GET_VALUE, args, &output);
+       if (err)
+               return err;
+
+       obj = output.pointer;
+       if (!obj)
+               return -EIO;
+
+       if (obj->type != ACPI_TYPE_INTEGER) {
+               err = -EIO;
+               goto out_free_obj;
+       }
+
+       err = 0;
+       *value = obj->integer.value;
+
+out_free_obj:
+       ACPI_FREE(obj);
+       return err;
+}
+
+static int asus_wmi_update_values_for_source(u8 source, struct asus_wmi_sensors *sensor_data)
+{
+       struct asus_wmi_sensor_info *sensor;
+       long value = 0;
+       int ret;
+       int i;
+
+       for (i = 0; i < sensor_data->wmi.sensor_count; i++) {
+               sensor = sensor_data->wmi.info_by_id[i];
+               if (sensor && sensor->source == source) {
+                       ret = asus_wmi_get_sensor_value(sensor->id, &value);
+                       if (ret)
+                               return ret;
+
+                       sensor->cached_value = value;
+               }
+       }
+
+       return 0;
+}
+
+static int asus_wmi_scale_sensor_value(u32 value, int data_type)
+{
+       /* FAN_RPM and WATER_FLOW don't need scaling */
+       switch (data_type) {
+       case VOLTAGE:
+               /* value in microVolts */
+               return DIV_ROUND_CLOSEST(value,  KILO);
+       case TEMPERATURE_C:
+               /* value in Celsius */
+               return value * MILLIDEGREE_PER_DEGREE;
+       case CURRENT:
+               /* value in Amperes */
+               return value * MILLI;
+       }
+       return value;
+}
+
+static int asus_wmi_get_cached_value_or_update(const struct asus_wmi_sensor_info *sensor,
+                                              struct asus_wmi_sensors *sensor_data,
+                                              u32 *value)
+{
+       int ret = 0;
+
+       mutex_lock(&sensor_data->lock);
+
+       if (time_after(jiffies, sensor_data->wmi.source_last_updated[sensor->source] + HZ)) {
+               ret = asus_wmi_update_buffer(sensor->source);
+               if (ret)
+                       goto unlock;
+
+               ret = asus_wmi_update_values_for_source(sensor->source, sensor_data);
+               if (ret)
+                       goto unlock;
+
+               sensor_data->wmi.source_last_updated[sensor->source] = jiffies;
+       }
+
+       *value = sensor->cached_value;
+
+unlock:
+       mutex_unlock(&sensor_data->lock);
+
+       return ret;
+}
+
+/* Now follow the functions that implement the hwmon interface */
+static int asus_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+                              u32 attr, int channel, long *val)
+{
+       const struct asus_wmi_sensor_info *sensor;
+       u32 value = 0;
+       int ret;
+
+       struct asus_wmi_sensors *sensor_data = dev_get_drvdata(dev);
+
+       sensor = *(sensor_data->wmi.info[type] + channel);
+
+       ret = asus_wmi_get_cached_value_or_update(sensor, sensor_data, &value);
+       if (ret)
+               return ret;
+
+       *val = asus_wmi_scale_sensor_value(value, sensor->data_type);
+
+       return ret;
+}
+
+static int asus_wmi_hwmon_read_string(struct device *dev,
+                                     enum hwmon_sensor_types type, u32 attr,
+                                     int channel, const char **str)
+{
+       struct asus_wmi_sensors *sensor_data = dev_get_drvdata(dev);
+       const struct asus_wmi_sensor_info *sensor;
+
+       sensor = *(sensor_data->wmi.info[type] + channel);
+       *str = sensor->name;
+
+       return 0;
+}
+
+static umode_t asus_wmi_hwmon_is_visible(const void *drvdata,
+                                        enum hwmon_sensor_types type, u32 attr,
+                                        int channel)
+{
+       const struct asus_wmi_sensors *sensor_data = drvdata;
+       const struct asus_wmi_sensor_info *sensor;
+
+       sensor = *(sensor_data->wmi.info[type] + channel);
+       if (sensor)
+               return 0444;
+
+       return 0;
+}
+
+static const struct hwmon_ops asus_wmi_hwmon_ops = {
+       .is_visible = asus_wmi_hwmon_is_visible,
+       .read = asus_wmi_hwmon_read,
+       .read_string = asus_wmi_hwmon_read_string,
+};
+
+static struct hwmon_chip_info asus_wmi_chip_info = {
+       .ops = &asus_wmi_hwmon_ops,
+       .info = NULL,
+};
+
+static int asus_wmi_configure_sensor_setup(struct device *dev,
+                                          struct asus_wmi_sensors *sensor_data)
+{
+       const struct hwmon_channel_info **ptr_asus_wmi_ci;
+       struct hwmon_channel_info *asus_wmi_hwmon_chan;
+       int nr_count[hwmon_max] = {}, nr_types = 0;
+       struct asus_wmi_sensor_info *temp_sensor;
+       const struct hwmon_chip_info *chip_info;
+       enum hwmon_sensor_types type;
+       struct device *hwdev;
+       int i, idx;
+       int err;
+
+       temp_sensor = devm_kcalloc(dev, 1, sizeof(*temp_sensor), GFP_KERNEL);
+       if (!temp_sensor)
+               return -ENOMEM;
+
+       for (i = 0; i < sensor_data->wmi.sensor_count; i++) {
+               err = asus_wmi_sensor_info(i, temp_sensor);
+               if (err)
+                       return err;
+
+               switch (temp_sensor->data_type) {
+               case TEMPERATURE_C:
+               case VOLTAGE:
+               case CURRENT:
+               case FAN_RPM:
+               case WATER_FLOW:
+                       type = asus_data_types[temp_sensor->data_type];
+                       if (!nr_count[type])
+                               nr_types++;
+                       nr_count[type]++;
+                       break;
+               }
+       }
+
+       if (nr_count[hwmon_temp])
+               nr_count[hwmon_chip]++, nr_types++;
+
+       asus_wmi_hwmon_chan = devm_kcalloc(dev, nr_types,
+                                          sizeof(*asus_wmi_hwmon_chan),
+                                          GFP_KERNEL);
+       if (!asus_wmi_hwmon_chan)
+               return -ENOMEM;
+
+       ptr_asus_wmi_ci = devm_kcalloc(dev, nr_types + 1,
+                                      sizeof(*ptr_asus_wmi_ci), GFP_KERNEL);
+       if (!ptr_asus_wmi_ci)
+               return -ENOMEM;
+
+       asus_wmi_chip_info.info = ptr_asus_wmi_ci;
+       chip_info = &asus_wmi_chip_info;
+
+       sensor_data->wmi.info_by_id = devm_kcalloc(dev, sensor_data->wmi.sensor_count,
+                                                  sizeof(*sensor_data->wmi.info_by_id),
+                                                  GFP_KERNEL);
+
+       if (!sensor_data->wmi.info_by_id)
+               return -ENOMEM;
+
+       for (type = 0; type < hwmon_max; type++) {
+               if (!nr_count[type])
+                       continue;
+
+               err = asus_wmi_hwmon_add_chan_info(asus_wmi_hwmon_chan, dev,
+                                                  nr_count[type], type,
+                                                  hwmon_attributes[type]);
+               if (err)
+                       return err;
+
+               *ptr_asus_wmi_ci++ = asus_wmi_hwmon_chan++;
+
+               sensor_data->wmi.info[type] = devm_kcalloc(dev,
+                                                          nr_count[type],
+                                                          sizeof(*sensor_data->wmi.info),
+                                                          GFP_KERNEL);
+               if (!sensor_data->wmi.info[type])
+                       return -ENOMEM;
+       }
+
+       for (i = sensor_data->wmi.sensor_count - 1; i >= 0; i--) {
+               temp_sensor = devm_kzalloc(dev, sizeof(*temp_sensor), GFP_KERNEL);
+               if (!temp_sensor)
+                       return -ENOMEM;
+
+               err = asus_wmi_sensor_info(i, temp_sensor);
+               if (err)
+                       continue;
+
+               switch (temp_sensor->data_type) {
+               case TEMPERATURE_C:
+               case VOLTAGE:
+               case CURRENT:
+               case FAN_RPM:
+               case WATER_FLOW:
+                       type = asus_data_types[temp_sensor->data_type];
+                       idx = --nr_count[type];
+                       *(sensor_data->wmi.info[type] + idx) = temp_sensor;
+                       sensor_data->wmi.info_by_id[i] = temp_sensor;
+                       break;
+               }
+       }
+
+       dev_dbg(dev, "board has %d sensors",
+               sensor_data->wmi.sensor_count);
+
+       hwdev = devm_hwmon_device_register_with_info(dev, "asus_wmi_sensors",
+                                                    sensor_data, chip_info, NULL);
+
+       return PTR_ERR_OR_ZERO(hwdev);
+}
+
+static int asus_wmi_probe(struct wmi_device *wdev, const void *context)
+{
+       struct asus_wmi_sensors *sensor_data;
+       struct device *dev = &wdev->dev;
+       u32 version = 0;
+
+       if (!dmi_check_system(asus_wmi_dmi_table))
+               return -ENODEV;
+
+       sensor_data = devm_kzalloc(dev, sizeof(*sensor_data), GFP_KERNEL);
+       if (!sensor_data)
+               return -ENOMEM;
+
+       if (asus_wmi_get_version(&version))
+               return -ENODEV;
+
+       if (asus_wmi_get_item_count(&sensor_data->wmi.sensor_count))
+               return -ENODEV;
+
+       if (sensor_data->wmi.sensor_count  <= 0 || version < 2) {
+               dev_info(dev, "version: %u with %d sensors is unsupported\n",
+                        version, sensor_data->wmi.sensor_count);
+
+               return -ENODEV;
+       }
+
+       mutex_init(&sensor_data->lock);
+
+       dev_set_drvdata(dev, sensor_data);
+
+       return asus_wmi_configure_sensor_setup(dev, sensor_data);
+}
+
+static const struct wmi_device_id asus_wmi_id_table[] = {
+       { ASUSWMI_MONITORING_GUID, NULL },
+       { }
+};
+
+static struct wmi_driver asus_sensors_wmi_driver = {
+       .driver = {
+               .name = "asus_wmi_sensors",
+       },
+       .id_table = asus_wmi_id_table,
+       .probe = asus_wmi_probe,
+};
+module_wmi_driver(asus_sensors_wmi_driver);
+
+MODULE_AUTHOR("Ed Brindley <kernel@maidavale.org>");
+MODULE_DESCRIPTION("Asus WMI Sensors Driver");
+MODULE_LICENSE("GPL");