hwmon: (core) New hwmon registration API
Up to now, each hwmon driver has to implement its own sysfs attributes.
This requires a lot of template code, and distracts from the driver's core
function to read and write chip registers.
To be able to reduce driver complexity, move sensor attribute handling
and thermal zone registration into hwmon core. By using the new API,
driver code and data size is typically reduced by 20-70%, depending
on driver complexity and the number of sysfs attributes supported.
With this patch, the new API only supports thermal sensors. Support for
other sensor types will be added with subsequent patches.
Acked-by: Punit Agrawal <punit.agrawal@arm.com>
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/include/linux/hwmon.h b/include/linux/hwmon.h
index 09354f6..52e56d7 100644
--- a/include/linux/hwmon.h
+++ b/include/linux/hwmon.h
@@ -14,9 +14,147 @@
#ifndef _HWMON_H_
#define _HWMON_H_
+#include <linux/bitops.h>
+
struct device;
struct attribute_group;
+enum hwmon_sensor_types {
+ hwmon_chip,
+ hwmon_temp,
+ hwmon_in,
+ hwmon_curr,
+ hwmon_power,
+ hwmon_energy,
+};
+
+enum hwmon_chip_attributes {
+ hwmon_chip_temp_reset_history,
+ hwmon_chip_register_tz,
+ hwmon_chip_update_interval,
+ hwmon_chip_alarms,
+};
+
+#define HWMON_C_TEMP_RESET_HISTORY BIT(hwmon_chip_temp_reset_history)
+#define HWMON_C_IN_RESET_HISTORY BIT(hwmon_chip_in_reset_history)
+#define HWMON_C_REGISTER_TZ BIT(hwmon_chip_register_tz)
+#define HWMON_C_UPDATE_INTERVAL BIT(hwmon_chip_update_interval)
+#define HWMON_C_ALARMS BIT(hwmon_chip_alarms)
+
+enum hwmon_temp_attributes {
+ hwmon_temp_input = 0,
+ hwmon_temp_type,
+ hwmon_temp_lcrit,
+ hwmon_temp_lcrit_hyst,
+ hwmon_temp_min,
+ hwmon_temp_min_hyst,
+ hwmon_temp_max,
+ hwmon_temp_max_hyst,
+ hwmon_temp_crit,
+ hwmon_temp_crit_hyst,
+ hwmon_temp_emergency,
+ hwmon_temp_emergency_hyst,
+ hwmon_temp_alarm,
+ hwmon_temp_lcrit_alarm,
+ hwmon_temp_min_alarm,
+ hwmon_temp_max_alarm,
+ hwmon_temp_crit_alarm,
+ hwmon_temp_emergency_alarm,
+ hwmon_temp_fault,
+ hwmon_temp_offset,
+ hwmon_temp_label,
+ hwmon_temp_lowest,
+ hwmon_temp_highest,
+ hwmon_temp_reset_history,
+};
+
+#define HWMON_T_INPUT BIT(hwmon_temp_input)
+#define HWMON_T_TYPE BIT(hwmon_temp_type)
+#define HWMON_T_LCRIT BIT(hwmon_temp_lcrit)
+#define HWMON_T_LCRIT_HYST BIT(hwmon_temp_lcrit_hyst)
+#define HWMON_T_MIN BIT(hwmon_temp_min)
+#define HWMON_T_MIN_HYST BIT(hwmon_temp_min_hyst)
+#define HWMON_T_MAX BIT(hwmon_temp_max)
+#define HWMON_T_MAX_HYST BIT(hwmon_temp_max_hyst)
+#define HWMON_T_CRIT BIT(hwmon_temp_crit)
+#define HWMON_T_CRIT_HYST BIT(hwmon_temp_crit_hyst)
+#define HWMON_T_EMERGENCY BIT(hwmon_temp_emergency)
+#define HWMON_T_EMERGENCY_HYST BIT(hwmon_temp_emergency_hyst)
+#define HWMON_T_MIN_ALARM BIT(hwmon_temp_min_alarm)
+#define HWMON_T_MAX_ALARM BIT(hwmon_temp_max_alarm)
+#define HWMON_T_CRIT_ALARM BIT(hwmon_temp_crit_alarm)
+#define HWMON_T_EMERGENCY_ALARM BIT(hwmon_temp_emergency_alarm)
+#define HWMON_T_FAULT BIT(hwmon_temp_fault)
+#define HWMON_T_OFFSET BIT(hwmon_temp_offset)
+#define HWMON_T_LABEL BIT(hwmon_temp_label)
+#define HWMON_T_LOWEST BIT(hwmon_temp_lowest)
+#define HWMON_T_HIGHEST BIT(hwmon_temp_highest)
+#define HWMON_T_RESET_HISTORY BIT(hwmon_temp_reset_history)
+
+/**
+ * struct hwmon_ops - hwmon device operations
+ * @is_visible: Callback to return attribute visibility. Mandatory.
+ * Parameters are:
+ * @const void *drvdata:
+ * Pointer to driver-private data structure passed
+ * as argument to hwmon_device_register_with_info().
+ * @type: Sensor type
+ * @attr: Sensor attribute
+ * @channel:
+ * Channel number
+ * The function returns the file permissions.
+ * If the return value is 0, no attribute will be created.
+ * @read: Read callback. Optional. If not provided, attributes
+ * will not be readable.
+ * Parameters are:
+ * @dev: Pointer to hardware monitoring device
+ * @type: Sensor type
+ * @attr: Sensor attribute
+ * @channel:
+ * Channel number
+ * @val: Pointer to returned value
+ * The function returns 0 on success or a negative error number.
+ * @write: Write callback. Optional. If not provided, attributes
+ * will not be writable.
+ * Parameters are:
+ * @dev: Pointer to hardware monitoring device
+ * @type: Sensor type
+ * @attr: Sensor attribute
+ * @channel:
+ * Channel number
+ * @val: Value to write
+ * The function returns 0 on success or a negative error number.
+ */
+struct hwmon_ops {
+ umode_t (*is_visible)(const void *drvdata, enum hwmon_sensor_types type,
+ u32 attr, int channel);
+ int (*read)(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val);
+ int (*write)(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val);
+};
+
+/**
+ * Channel information
+ * @type: Channel type.
+ * @config: Pointer to NULL-terminated list of channel parameters.
+ * Use for per-channel attributes.
+ */
+struct hwmon_channel_info {
+ enum hwmon_sensor_types type;
+ const u32 *config;
+};
+
+/**
+ * Chip configuration
+ * @ops: Pointer to hwmon operations.
+ * @info: Null-terminated list of channel information.
+ */
+struct hwmon_chip_info {
+ const struct hwmon_ops *ops;
+ const struct hwmon_channel_info **info;
+};
+
struct device *hwmon_device_register(struct device *dev);
struct device *
hwmon_device_register_with_groups(struct device *dev, const char *name,
@@ -26,6 +164,16 @@
devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
void *drvdata,
const struct attribute_group **groups);
+struct device *
+hwmon_device_register_with_info(struct device *dev,
+ const char *name, void *drvdata,
+ const struct hwmon_chip_info *info,
+ const struct attribute_group **groups);
+struct device *
+devm_hwmon_device_register_with_info(struct device *dev,
+ const char *name, void *drvdata,
+ const struct hwmon_chip_info *info,
+ const struct attribute_group **groups);
void hwmon_device_unregister(struct device *dev);
void devm_hwmon_device_unregister(struct device *dev);