+the call to devm_hwmon_device_register_with_groups and if the automatic
+(device managed) removal would be too late.
+
+Using devm_hwmon_device_register_with_info()
+--------------------------------------------
+
+hwmon_device_register_with_info() registers a hardware monitoring device.
+The parameters to this function are
+
+struct device *dev Pointer to parent device
+const char *name Device name
+void *drvdata Driver private data
+const struct hwmon_chip_info *info
+ Pointer to chip description.
+const struct attribute_group **groups
+ Null-terminated list of additional sysfs attribute
+ groups.
+
+This function returns a pointer to the created hardware monitoring device
+on success and a negative error code for failure.
+
+The hwmon_chip_info structure looks as follows.
+
+struct hwmon_chip_info {
+ const struct hwmon_ops *ops;
+ const struct hwmon_channel_info **info;
+};
+
+It contains the following fields:
+
+* ops: Pointer to device operations.
+* info: NULL-terminated list of device channel descriptors.
+
+The list of hwmon operations is defined as:
+
+struct hwmon_ops {
+ umode_t (*is_visible)(const void *, enum hwmon_sensor_types type,
+ u32 attr, int);
+ int (*read)(struct device *, enum hwmon_sensor_types type,
+ u32 attr, int, long *);
+ int (*write)(struct device *, enum hwmon_sensor_types type,
+ u32 attr, int, long);
+};
+
+It defines the following operations.
+
+* is_visible: Pointer to a function to return the file mode for each supported
+ attribute. This function is mandatory.
+
+* read: Pointer to a function for reading a value from the chip. This function
+ is optional, but must be provided if any readable attributes exist.
+
+* write: Pointer to a function for writing a value to the chip. This function is
+ optional, but must be provided if any writeable attributes exist.
+
+Each sensor channel is described with struct hwmon_channel_info, which is
+defined as follows.
+
+struct hwmon_channel_info {
+ enum hwmon_sensor_types type;
+ u32 *config;
+};
+
+It contains following fields:
+
+* type: The hardware monitoring sensor type.
+ Supported sensor types are
+ * hwmon_chip A virtual sensor type, used to describe attributes
+ which apply to the entire chip.
+ * hwmon_temp Temperature sensor
+ * hwmon_in Voltage sensor
+ * hwmon_curr Current sensor
+ * hwmon_power Power sensor
+ * hwmon_energy Energy sensor
+ * hwmon_humidity Humidity sensor
+ * hwmon_fan Fan speed sensor
+ * hwmon_pwm PWM control
+
+* config: Pointer to a 0-terminated list of configuration values for each
+ sensor of the given type. Each value is a combination of bit values
+ describing the attributes supposed by a single sensor.
+
+As an example, here is the complete description file for a LM75 compatible
+sensor chip. The chip has a single temperature sensor. The driver wants to
+register with the thermal subsystem (HWMON_C_REGISTER_TZ), and it supports
+the update_interval attribute (HWMON_C_UPDATE_INTERVAL). The chip supports
+reading the temperature (HWMON_T_INPUT), it has a maximum temperature
+register (HWMON_T_MAX) as well as a maximum temperature hysteresis register
+(HWMON_T_MAX_HYST).
+
+static const u32 lm75_chip_config[] = {
+ HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL,
+ 0
+};
+
+static const struct hwmon_channel_info lm75_chip = {
+ .type = hwmon_chip,
+ .config = lm75_chip_config,
+};
+
+static const u32 lm75_temp_config[] = {
+ HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST,
+ 0
+};
+
+static const struct hwmon_channel_info lm75_temp = {
+ .type = hwmon_temp,
+ .config = lm75_temp_config,
+};
+
+static const struct hwmon_channel_info *lm75_info[] = {
+ &lm75_chip,
+ &lm75_temp,
+ NULL
+};
+
+static const struct hwmon_ops lm75_hwmon_ops = {
+ .is_visible = lm75_is_visible,
+ .read = lm75_read,
+ .write = lm75_write,
+};
+
+static const struct hwmon_chip_info lm75_chip_info = {
+ .ops = &lm75_hwmon_ops,
+ .info = lm75_info,
+};
+
+A complete list of bit values indicating individual attribute support
+is defined in include/linux/hwmon.h. Definition prefixes are as follows.
+
+HWMON_C_xxxx Chip attributes, for use with hwmon_chip.
+HWMON_T_xxxx Temperature attributes, for use with hwmon_temp.
+HWMON_I_xxxx Voltage attributes, for use with hwmon_in.
+HWMON_C_xxxx Current attributes, for use with hwmon_curr.
+ Notice the prefix overlap with chip attributes.
+HWMON_P_xxxx Power attributes, for use with hwmon_power.
+HWMON_E_xxxx Energy attributes, for use with hwmon_energy.
+HWMON_H_xxxx Humidity attributes, for use with hwmon_humidity.
+HWMON_F_xxxx Fan speed attributes, for use with hwmon_fan.
+HWMON_PWM_xxxx PWM control attributes, for use with hwmon_pwm.
+
+Driver callback functions
+-------------------------
+
+Each driver provides is_visible, read, and write functions. Parameters
+and return values for those functions are as follows.
+
+umode_t is_visible_func(const void *data, enum hwmon_sensor_types type,
+ u32 attr, int channel)
+
+Parameters:
+ data: Pointer to device private data structure.
+ type: The sensor type.
+ attr: Attribute identifier associated with a specific attribute.
+ For example, the attribute value for HWMON_T_INPUT would be
+ hwmon_temp_input. For complete mappings of bit fields to
+ attribute values please see include/linux/hwmon.h.
+ channel:The sensor channel number.
+
+Return value:
+ The file mode for this attribute. Typically, this will be 0 (the
+ attribute will not be created), S_IRUGO, or 'S_IRUGO | S_IWUSR'.
+
+int read_func(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+
+Parameters:
+ dev: Pointer to the hardware monitoring device.
+ type: The sensor type.
+ attr: Attribute identifier associated with a specific attribute.
+ For example, the attribute value for HWMON_T_INPUT would be
+ hwmon_temp_input. For complete mappings please see
+ include/linux/hwmon.h.
+ channel:The sensor channel number.
+ val: Pointer to attribute value.
+
+Return value:
+ 0 on success, a negative error number otherwise.
+
+int write_func(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+
+Parameters:
+ dev: Pointer to the hardware monitoring device.
+ type: The sensor type.
+ attr: Attribute identifier associated with a specific attribute.
+ For example, the attribute value for HWMON_T_INPUT would be
+ hwmon_temp_input. For complete mappings please see
+ include/linux/hwmon.h.
+ channel:The sensor channel number.
+ val: The value to write to the chip.
+
+Return value:
+ 0 on success, a negative error number otherwise.
+
+
+Driver-provided sysfs attributes
+--------------------------------
+
+If the hardware monitoring device is registered with
+hwmon_device_register_with_info or devm_hwmon_device_register_with_info,
+it is most likely not necessary to provide sysfs attributes. Only non-standard
+sysfs attributes need to be provided when one of those registration functions
+is used.