// SPDX-License-Identifier: GPL-2.0-only
/*
 * hwmon.c - part of lm_sensors, Linux kernel modules for hardware monitoring
 *
 * This file defines the sysfs class "hwmon", for use by sensors drivers.
 *
 * Copyright (C) 2005 Mark M. Hoffman <mhoffman@lightlink.com>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/gfp.h>
#include <linux/hwmon.h>
#include <linux/i2c.h>
#include <linux/idr.h>
#include <linux/kstrtox.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/thermal.h>

#define CREATE_TRACE_POINTS
#include <trace/events/hwmon.h>

#define HWMON_ID_PREFIX "hwmon"
#define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"

struct hwmon_device {
        const char *name;
        const char *label;
        struct device dev;
        const struct hwmon_chip_info *chip;
        struct mutex lock;
        struct list_head tzdata;
        struct attribute_group group;
        const struct attribute_group **groups;
};

#define to_hwmon_device(d) container_of(d, struct hwmon_device, dev)

#define MAX_SYSFS_ATTR_NAME_LENGTH      32

struct hwmon_device_attribute {
        struct device_attribute dev_attr;
        const struct hwmon_ops *ops;
        enum hwmon_sensor_types type;
        u32 attr;
        int index;
        char name[MAX_SYSFS_ATTR_NAME_LENGTH];
};

#define to_hwmon_attr(d) \
        container_of(d, struct hwmon_device_attribute, dev_attr)
#define to_dev_attr(a) container_of(a, struct device_attribute, attr)

/*
 * Thermal zone information
 */
struct hwmon_thermal_data {
        struct list_head node;          /* hwmon tzdata list entry */
        struct device *dev;             /* Reference to hwmon device */
        int index;                      /* sensor index */
        struct thermal_zone_device *tzd;/* thermal zone device */
};

static ssize_t
name_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        return sysfs_emit(buf, "%s\n", to_hwmon_device(dev)->name);
}
static DEVICE_ATTR_RO(name);

static ssize_t
label_show(struct device *dev, struct device_attribute *attr, char *buf)
{
        return sysfs_emit(buf, "%s\n", to_hwmon_device(dev)->label);
}
static DEVICE_ATTR_RO(label);

static struct attribute *hwmon_dev_attrs[] = {
        &dev_attr_name.attr,
        &dev_attr_label.attr,
        NULL
};

static umode_t hwmon_dev_attr_is_visible(struct kobject *kobj,
                                         struct attribute *attr, int n)
{
        struct device *dev = kobj_to_dev(kobj);
        struct hwmon_device *hdev = to_hwmon_device(dev);

        if (attr == &dev_attr_name.attr && hdev->name == NULL)
                return 0;

        if (attr == &dev_attr_label.attr && hdev->label == NULL)
                return 0;

        return attr->mode;
}

static const struct attribute_group hwmon_dev_attr_group = {
        .attrs          = hwmon_dev_attrs,
        .is_visible     = hwmon_dev_attr_is_visible,
};

static const struct attribute_group *hwmon_dev_attr_groups[] = {
        &hwmon_dev_attr_group,
        NULL
};

static void hwmon_free_attrs(struct attribute **attrs)
{
        int i;

        for (i = 0; attrs[i]; i++) {
                struct device_attribute *dattr = to_dev_attr(attrs[i]);
                struct hwmon_device_attribute *hattr = to_hwmon_attr(dattr);

                kfree(hattr);
        }
        kfree(attrs);
}

static void hwmon_dev_release(struct device *dev)
{
        struct hwmon_device *hwdev = to_hwmon_device(dev);

        if (hwdev->group.attrs)
                hwmon_free_attrs(hwdev->group.attrs);
        kfree(hwdev->groups);
        kfree(hwdev->label);
        kfree(hwdev);
}

static const struct class hwmon_class = {
        .name = "hwmon",
        .dev_groups = hwmon_dev_attr_groups,
        .dev_release = hwmon_dev_release,
};

static DEFINE_IDA(hwmon_ida);

static umode_t hwmon_is_visible(const struct hwmon_ops *ops,
                                const void *drvdata,
                                enum hwmon_sensor_types type,
                                u32 attr, int channel)
{
        if (ops->visible)
                return ops->visible;

        return ops->is_visible(drvdata, type, attr, channel);
}

/* Thermal zone handling */

static int hwmon_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
{
        struct hwmon_thermal_data *tdata = thermal_zone_device_priv(tz);
        struct hwmon_device *hwdev = to_hwmon_device(tdata->dev);
        int ret;
        long t;

        guard(mutex)(&hwdev->lock);

        ret = hwdev->chip->ops->read(tdata->dev, hwmon_temp, hwmon_temp_input,
                                     tdata->index, &t);
        if (ret < 0)
                return ret;

        *temp = t;

        return 0;
}

static int hwmon_thermal_set_trips(struct thermal_zone_device *tz, int low, int high)
{
        struct hwmon_thermal_data *tdata = thermal_zone_device_priv(tz);
        struct hwmon_device *hwdev = to_hwmon_device(tdata->dev);
        const struct hwmon_chip_info *chip = hwdev->chip;
        const struct hwmon_channel_info * const *info = chip->info;
        unsigned int i;
        int err;

        if (!chip->ops->write)
                return 0;

        for (i = 0; info[i] && info[i]->type != hwmon_temp; i++)
                continue;

        if (!info[i])
                return 0;

        guard(mutex)(&hwdev->lock);

        if (info[i]->config[tdata->index] & HWMON_T_MIN) {
                err = chip->ops->write(tdata->dev, hwmon_temp,
                                       hwmon_temp_min, tdata->index, low);
                if (err && err != -EOPNOTSUPP)
                        return err;
        }

        if (info[i]->config[tdata->index] & HWMON_T_MAX) {
                err = chip->ops->write(tdata->dev, hwmon_temp,
                                       hwmon_temp_max, tdata->index, high);
                if (err && err != -EOPNOTSUPP)
                        return err;
        }

        return 0;
}

static const struct thermal_zone_device_ops hwmon_thermal_ops = {
        .get_temp = hwmon_thermal_get_temp,
        .set_trips = hwmon_thermal_set_trips,
};

static void hwmon_thermal_remove_sensor(void *data)
{
        list_del(data);
}

static int hwmon_thermal_add_sensor(struct device *dev, int index)
{
        struct hwmon_device *hwdev = to_hwmon_device(dev);
        struct hwmon_thermal_data *tdata;
        struct thermal_zone_device *tzd;
        int err;

        tdata = devm_kzalloc(dev, sizeof(*tdata), GFP_KERNEL);
        if (!tdata)
                return -ENOMEM;

        tdata->dev = dev;
        tdata->index = index;

        tzd = devm_thermal_of_zone_register(dev, index, tdata,
                                            &hwmon_thermal_ops);
        if (IS_ERR(tzd)) {
                if (PTR_ERR(tzd) != -ENODEV)
                        return PTR_ERR(tzd);
                dev_info(dev, "temp%d_input not attached to any thermal zone\n",
                         index + 1);
                devm_kfree(dev, tdata);
                return 0;
        }

        err = devm_add_action(dev, hwmon_thermal_remove_sensor, &tdata->node);
        if (err)
                return err;

        tdata->tzd = tzd;
        list_add(&tdata->node, &hwdev->tzdata);

        return 0;
}

static int hwmon_thermal_register_sensors(struct device *dev)
{
        struct hwmon_device *hwdev = to_hwmon_device(dev);
        const struct hwmon_chip_info *chip = hwdev->chip;
        const struct hwmon_channel_info * const *info = chip->info;
        void *drvdata = dev_get_drvdata(dev);
        int i;

        if (!IS_ENABLED(CONFIG_THERMAL_OF))
                return 0;

        for (i = 1; info[i]; i++) {
                int j;

                if (info[i]->type != hwmon_temp)
                        continue;

                for (j = 0; info[i]->config[j]; j++) {
                        int err;

                        if (!(info[i]->config[j] & HWMON_T_INPUT) ||
                            !hwmon_is_visible(chip->ops, drvdata, hwmon_temp,
                                              hwmon_temp_input, j))
                                continue;

                        err = hwmon_thermal_add_sensor(dev, j);
                        if (err)
                                return err;
                }
        }

        return 0;
}

static void hwmon_thermal_notify(struct device *dev, int index)
{
        struct hwmon_device *hwdev = to_hwmon_device(dev);
        struct hwmon_thermal_data *tzdata;

        if (!IS_ENABLED(CONFIG_THERMAL_OF))
                return;

        list_for_each_entry(tzdata, &hwdev->tzdata, node) {
                if (tzdata->index == index) {
                        thermal_zone_device_update(tzdata->tzd,
                                                   THERMAL_EVENT_UNSPECIFIED);
                }
        }
}

static int hwmon_attr_base(enum hwmon_sensor_types type)
{
        if (type == hwmon_in || type == hwmon_intrusion)
                return 0;
        return 1;
}

#if IS_REACHABLE(CONFIG_I2C)

/*
 * PEC support
 *
 * The 'pec' attribute is attached to I2C client devices. It is only provided
 * if the i2c controller supports PEC.
 *
 * The mutex ensures that PEC configuration between i2c device and the hardware
 * is consistent. Use a single mutex because attribute writes are supposed to be
 * rare, and maintaining a separate mutex for each hardware monitoring device
 * would add substantial complexity to the driver for little if any gain.
 *
 * The hardware monitoring device is identified as child of the i2c client
 * device. This assumes that only a single hardware monitoring device is
 * attached to an i2c client device.
 */

static int hwmon_match_device(struct device *dev, const void *data)
{
        return dev->class == &hwmon_class;
}

static ssize_t pec_show(struct device *dev, struct device_attribute *dummy,
                        char *buf)
{
        struct i2c_client *client = to_i2c_client(dev);

        return sysfs_emit(buf, "%d\n", !!(client->flags & I2C_CLIENT_PEC));
}

static ssize_t pec_store(struct device *dev, struct device_attribute *devattr,
                         const char *buf, size_t count)
{
        struct i2c_client *client = to_i2c_client(dev);
        struct hwmon_device *hwdev;
        struct device *hdev;
        bool val;
        int err;

        err = kstrtobool(buf, &val);
        if (err < 0)
                return err;

        hdev = device_find_child(dev, NULL, hwmon_match_device);
        if (!hdev)
                return -ENODEV;

        /*
         * If there is no write function, we assume that chip specific
         * handling is not required.
         */
        hwdev = to_hwmon_device(hdev);
        guard(mutex)(&hwdev->lock);
        if (hwdev->chip->ops->write) {
                err = hwdev->chip->ops->write(hdev, hwmon_chip, hwmon_chip_pec, 0, val);
                if (err && err != -EOPNOTSUPP)
                        goto put;
        }

        if (!val)
                client->flags &= ~I2C_CLIENT_PEC;
        else
                client->flags |= I2C_CLIENT_PEC;

        err = count;
put:
        put_device(hdev);

        return err;
}

static DEVICE_ATTR_RW(pec);

static void hwmon_remove_pec(void *dev)
{
        device_remove_file(dev, &dev_attr_pec);
}

static int hwmon_pec_register(struct device *hdev)
{
        struct i2c_client *client = i2c_verify_client(hdev->parent);
        int err;

        if (!client)
                return -EINVAL;

        if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_PEC))
                return 0;

        err = device_create_file(&client->dev, &dev_attr_pec);
        if (err)
                return err;

        return devm_add_action_or_reset(hdev, hwmon_remove_pec, &client->dev);
}

#else /* CONFIG_I2C */
static int hwmon_pec_register(struct device *hdev)
{
        return -EINVAL;
}
#endif /* CONFIG_I2C */

/* sysfs attribute management */

static ssize_t hwmon_attr_show(struct device *dev,
                               struct device_attribute *devattr, char *buf)
{
        struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
        struct hwmon_device *hwdev = to_hwmon_device(dev);
        s64 val64;
        long val;
        int ret;

        guard(mutex)(&hwdev->lock);

        ret = hattr->ops->read(dev, hattr->type, hattr->attr, hattr->index,
                               (hattr->type == hwmon_energy64) ? (long *)&val64 : &val);
        if (ret < 0)
                return ret;

        if (hattr->type != hwmon_energy64)
                val64 = val;

        trace_hwmon_attr_show(hattr->index + hwmon_attr_base(hattr->type),
                              hattr->name, val64);

        return sysfs_emit(buf, "%lld\n", val64);
}

static ssize_t hwmon_attr_show_string(struct device *dev,
                                      struct device_attribute *devattr,
                                      char *buf)
{
        struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
        struct hwmon_device *hwdev = to_hwmon_device(dev);
        enum hwmon_sensor_types type = hattr->type;
        const char *s;
        int ret;

        guard(mutex)(&hwdev->lock);

        ret = hattr->ops->read_string(dev, hattr->type, hattr->attr,
                                      hattr->index, &s);
        if (ret < 0)
                return ret;

        trace_hwmon_attr_show_string(hattr->index + hwmon_attr_base(type),
                                     hattr->name, s);

        return sysfs_emit(buf, "%s\n", s);
}

static ssize_t hwmon_attr_store(struct device *dev,
                                struct device_attribute *devattr,
                                const char *buf, size_t count)
{
        struct hwmon_device_attribute *hattr = to_hwmon_attr(devattr);
        struct hwmon_device *hwdev = to_hwmon_device(dev);
        long val;
        int ret;

        ret = kstrtol(buf, 10, &val);
        if (ret < 0)
                return ret;

        guard(mutex)(&hwdev->lock);

        ret = hattr->ops->write(dev, hattr->type, hattr->attr, hattr->index,
                                val);
        if (ret < 0)
                return ret;

        trace_hwmon_attr_store(hattr->index + hwmon_attr_base(hattr->type),
                               hattr->name, (s64)val);

        return count;
}

static bool is_string_attr(enum hwmon_sensor_types type, u32 attr)
{
        return (type == hwmon_temp && attr == hwmon_temp_label) ||
               (type == hwmon_in && attr == hwmon_in_label) ||
               (type == hwmon_curr && attr == hwmon_curr_label) ||
               (type == hwmon_power && attr == hwmon_power_label) ||
               (type == hwmon_energy && attr == hwmon_energy_label) ||
               (type == hwmon_humidity && attr == hwmon_humidity_label) ||
               (type == hwmon_fan && attr == hwmon_fan_label);
}

static struct attribute *hwmon_genattr(const void *drvdata,
                                       enum hwmon_sensor_types type,
                                       u32 attr,
                                       int index,
                                       const char *template,
                                       const struct hwmon_ops *ops)
{
        struct hwmon_device_attribute *hattr;
        struct device_attribute *dattr;
        struct attribute *a;
        umode_t mode;
        const char *name;
        bool is_string = is_string_attr(type, attr);

        mode = hwmon_is_visible(ops, drvdata, type, attr, index);
        if (!mode)
                return ERR_PTR(-ENOENT);

        if ((mode & 0444) && ((is_string && !ops->read_string) ||
                                 (!is_string && !ops->read)))
                return ERR_PTR(-EINVAL);
        if ((mode & 0222) && !ops->write)
                return ERR_PTR(-EINVAL);

        hattr = kzalloc_obj(*hattr);
        if (!hattr)
                return ERR_PTR(-ENOMEM);

        if (type == hwmon_chip) {
                name = template;
        } else {
                scnprintf(hattr->name, sizeof(hattr->name), template,
                          index + hwmon_attr_base(type));
                name = hattr->name;
        }

        hattr->type = type;
        hattr->attr = attr;
        hattr->index = index;
        hattr->ops = ops;

        dattr = &hattr->dev_attr;
        dattr->show = is_string ? hwmon_attr_show_string : hwmon_attr_show;
        dattr->store = hwmon_attr_store;

        a = &dattr->attr;
        sysfs_attr_init(a);
        a->name = name;
        a->mode = mode;

        return a;
}

/*
 * Chip attributes are not attribute templates but actual sysfs attributes.
 * See hwmon_genattr() for special handling.
 */
static const char * const hwmon_chip_attrs[] = {
        [hwmon_chip_temp_reset_history] = "temp_reset_history",
        [hwmon_chip_in_reset_history] = "in_reset_history",
        [hwmon_chip_curr_reset_history] = "curr_reset_history",
        [hwmon_chip_power_reset_history] = "power_reset_history",
        [hwmon_chip_update_interval] = "update_interval",
        [hwmon_chip_alarms] = "alarms",
        [hwmon_chip_samples] = "samples",
        [hwmon_chip_curr_samples] = "curr_samples",
        [hwmon_chip_in_samples] = "in_samples",
        [hwmon_chip_power_samples] = "power_samples",
        [hwmon_chip_temp_samples] = "temp_samples",
        [hwmon_chip_beep_enable] = "beep_enable",
};

static const char * const hwmon_temp_attr_templates[] = {
        [hwmon_temp_enable] = "temp%d_enable",
        [hwmon_temp_input] = "temp%d_input",
        [hwmon_temp_type] = "temp%d_type",
        [hwmon_temp_lcrit] = "temp%d_lcrit",
        [hwmon_temp_lcrit_hyst] = "temp%d_lcrit_hyst",
        [hwmon_temp_min] = "temp%d_min",
        [hwmon_temp_min_hyst] = "temp%d_min_hyst",
        [hwmon_temp_max] = "temp%d_max",
        [hwmon_temp_max_hyst] = "temp%d_max_hyst",
        [hwmon_temp_crit] = "temp%d_crit",
        [hwmon_temp_crit_hyst] = "temp%d_crit_hyst",
        [hwmon_temp_emergency] = "temp%d_emergency",
        [hwmon_temp_emergency_hyst] = "temp%d_emergency_hyst",
        [hwmon_temp_alarm] = "temp%d_alarm",
        [hwmon_temp_lcrit_alarm] = "temp%d_lcrit_alarm",
        [hwmon_temp_min_alarm] = "temp%d_min_alarm",
        [hwmon_temp_max_alarm] = "temp%d_max_alarm",
        [hwmon_temp_crit_alarm] = "temp%d_crit_alarm",
        [hwmon_temp_emergency_alarm] = "temp%d_emergency_alarm",
        [hwmon_temp_fault] = "temp%d_fault",
        [hwmon_temp_offset] = "temp%d_offset",
        [hwmon_temp_label] = "temp%d_label",
        [hwmon_temp_lowest] = "temp%d_lowest",
        [hwmon_temp_highest] = "temp%d_highest",
        [hwmon_temp_reset_history] = "temp%d_reset_history",
        [hwmon_temp_rated_min] = "temp%d_rated_min",
        [hwmon_temp_rated_max] = "temp%d_rated_max",
        [hwmon_temp_beep] = "temp%d_beep",
};

static const char * const hwmon_in_attr_templates[] = {
        [hwmon_in_enable] = "in%d_enable",
        [hwmon_in_input] = "in%d_input",
        [hwmon_in_min] = "in%d_min",
        [hwmon_in_max] = "in%d_max",
        [hwmon_in_lcrit] = "in%d_lcrit",
        [hwmon_in_crit] = "in%d_crit",
        [hwmon_in_average] = "in%d_average",
        [hwmon_in_lowest] = "in%d_lowest",
        [hwmon_in_highest] = "in%d_highest",
        [hwmon_in_reset_history] = "in%d_reset_history",
        [hwmon_in_label] = "in%d_label",
        [hwmon_in_alarm] = "in%d_alarm",
        [hwmon_in_min_alarm] = "in%d_min_alarm",
        [hwmon_in_max_alarm] = "in%d_max_alarm",
        [hwmon_in_lcrit_alarm] = "in%d_lcrit_alarm",
        [hwmon_in_crit_alarm] = "in%d_crit_alarm",
        [hwmon_in_rated_min] = "in%d_rated_min",
        [hwmon_in_rated_max] = "in%d_rated_max",
        [hwmon_in_beep] = "in%d_beep",
        [hwmon_in_fault] = "in%d_fault",
};

static const char * const hwmon_curr_attr_templates[] = {
        [hwmon_curr_enable] = "curr%d_enable",
        [hwmon_curr_input] = "curr%d_input",
        [hwmon_curr_min] = "curr%d_min",
        [hwmon_curr_max] = "curr%d_max",
        [hwmon_curr_lcrit] = "curr%d_lcrit",
        [hwmon_curr_crit] = "curr%d_crit",
        [hwmon_curr_average] = "curr%d_average",
        [hwmon_curr_lowest] = "curr%d_lowest",
        [hwmon_curr_highest] = "curr%d_highest",
        [hwmon_curr_reset_history] = "curr%d_reset_history",
        [hwmon_curr_label] = "curr%d_label",
        [hwmon_curr_alarm] = "curr%d_alarm",
        [hwmon_curr_min_alarm] = "curr%d_min_alarm",
        [hwmon_curr_max_alarm] = "curr%d_max_alarm",
        [hwmon_curr_lcrit_alarm] = "curr%d_lcrit_alarm",
        [hwmon_curr_crit_alarm] = "curr%d_crit_alarm",
        [hwmon_curr_rated_min] = "curr%d_rated_min",
        [hwmon_curr_rated_max] = "curr%d_rated_max",
        [hwmon_curr_beep] = "curr%d_beep",
};

static const char * const hwmon_power_attr_templates[] = {
        [hwmon_power_enable] = "power%d_enable",
        [hwmon_power_average] = "power%d_average",
        [hwmon_power_average_interval] = "power%d_average_interval",
        [hwmon_power_average_interval_max] = "power%d_average_interval_max",
        [hwmon_power_average_interval_min] = "power%d_average_interval_min",
        [hwmon_power_average_highest] = "power%d_average_highest",
        [hwmon_power_average_lowest] = "power%d_average_lowest",
        [hwmon_power_average_max] = "power%d_average_max",
        [hwmon_power_average_min] = "power%d_average_min",
        [hwmon_power_input] = "power%d_input",
        [hwmon_power_input_highest] = "power%d_input_highest",
        [hwmon_power_input_lowest] = "power%d_input_lowest",
        [hwmon_power_reset_history] = "power%d_reset_history",
        [hwmon_power_accuracy] = "power%d_accuracy",
        [hwmon_power_cap] = "power%d_cap",
        [hwmon_power_cap_hyst] = "power%d_cap_hyst",
        [hwmon_power_cap_max] = "power%d_cap_max",
        [hwmon_power_cap_min] = "power%d_cap_min",
        [hwmon_power_min] = "power%d_min",
        [hwmon_power_max] = "power%d_max",
        [hwmon_power_lcrit] = "power%d_lcrit",
        [hwmon_power_crit] = "power%d_crit",
        [hwmon_power_label] = "power%d_label",
        [hwmon_power_alarm] = "power%d_alarm",
        [hwmon_power_cap_alarm] = "power%d_cap_alarm",
        [hwmon_power_min_alarm] = "power%d_min_alarm",
        [hwmon_power_max_alarm] = "power%d_max_alarm",
        [hwmon_power_lcrit_alarm] = "power%d_lcrit_alarm",
        [hwmon_power_crit_alarm] = "power%d_crit_alarm",
        [hwmon_power_rated_min] = "power%d_rated_min",
        [hwmon_power_rated_max] = "power%d_rated_max",
};

static const char * const hwmon_energy_attr_templates[] = {
        [hwmon_energy_enable] = "energy%d_enable",
        [hwmon_energy_input] = "energy%d_input",
        [hwmon_energy_label] = "energy%d_label",
};

static const char * const hwmon_humidity_attr_templates[] = {
        [hwmon_humidity_enable] = "humidity%d_enable",
        [hwmon_humidity_input] = "humidity%d_input",
        [hwmon_humidity_label] = "humidity%d_label",
        [hwmon_humidity_min] = "humidity%d_min",
        [hwmon_humidity_min_hyst] = "humidity%d_min_hyst",
        [hwmon_humidity_max] = "humidity%d_max",
        [hwmon_humidity_max_hyst] = "humidity%d_max_hyst",
        [hwmon_humidity_alarm] = "humidity%d_alarm",
        [hwmon_humidity_fault] = "humidity%d_fault",
        [hwmon_humidity_rated_min] = "humidity%d_rated_min",
        [hwmon_humidity_rated_max] = "humidity%d_rated_max",
        [hwmon_humidity_min_alarm] = "humidity%d_min_alarm",
        [hwmon_humidity_max_alarm] = "humidity%d_max_alarm",
};

static const char * const hwmon_fan_attr_templates[] = {
        [hwmon_fan_enable] = "fan%d_enable",
        [hwmon_fan_input] = "fan%d_input",
        [hwmon_fan_label] = "fan%d_label",
        [hwmon_fan_min] = "fan%d_min",
        [hwmon_fan_max] = "fan%d_max",
        [hwmon_fan_div] = "fan%d_div",
        [hwmon_fan_pulses] = "fan%d_pulses",
        [hwmon_fan_target] = "fan%d_target",
        [hwmon_fan_alarm] = "fan%d_alarm",
        [hwmon_fan_min_alarm] = "fan%d_min_alarm",
        [hwmon_fan_max_alarm] = "fan%d_max_alarm",
        [hwmon_fan_fault] = "fan%d_fault",
        [hwmon_fan_beep] = "fan%d_beep",
};

static const char * const hwmon_pwm_attr_templates[] = {
        [hwmon_pwm_input] = "pwm%d",
        [hwmon_pwm_enable] = "pwm%d_enable",
        [hwmon_pwm_mode] = "pwm%d_mode",
        [hwmon_pwm_freq] = "pwm%d_freq",
        [hwmon_pwm_auto_channels_temp] = "pwm%d_auto_channels_temp",
};

static const char * const hwmon_intrusion_attr_templates[] = {
        [hwmon_intrusion_alarm] = "intrusion%d_alarm",
        [hwmon_intrusion_beep]  = "intrusion%d_beep",
};

static const char * const *__templates[] = {
        [hwmon_chip] = hwmon_chip_attrs,
        [hwmon_temp] = hwmon_temp_attr_templates,
        [hwmon_in] = hwmon_in_attr_templates,
        [hwmon_curr] = hwmon_curr_attr_templates,
        [hwmon_power] = hwmon_power_attr_templates,
        [hwmon_energy] = hwmon_energy_attr_templates,
        [hwmon_energy64] = hwmon_energy_attr_templates,
        [hwmon_humidity] = hwmon_humidity_attr_templates,
        [hwmon_fan] = hwmon_fan_attr_templates,
        [hwmon_pwm] = hwmon_pwm_attr_templates,
        [hwmon_intrusion] = hwmon_intrusion_attr_templates,
};

static const int __templates_size[] = {
        [hwmon_chip] = ARRAY_SIZE(hwmon_chip_attrs),
        [hwmon_temp] = ARRAY_SIZE(hwmon_temp_attr_templates),
        [hwmon_in] = ARRAY_SIZE(hwmon_in_attr_templates),
        [hwmon_curr] = ARRAY_SIZE(hwmon_curr_attr_templates),
        [hwmon_power] = ARRAY_SIZE(hwmon_power_attr_templates),
        [hwmon_energy] = ARRAY_SIZE(hwmon_energy_attr_templates),
        [hwmon_energy64] = ARRAY_SIZE(hwmon_energy_attr_templates),
        [hwmon_humidity] = ARRAY_SIZE(hwmon_humidity_attr_templates),
        [hwmon_fan] = ARRAY_SIZE(hwmon_fan_attr_templates),
        [hwmon_pwm] = ARRAY_SIZE(hwmon_pwm_attr_templates),
        [hwmon_intrusion] = ARRAY_SIZE(hwmon_intrusion_attr_templates),
};

int hwmon_notify_event(struct device *dev, enum hwmon_sensor_types type,
                       u32 attr, int channel)
{
        char event[MAX_SYSFS_ATTR_NAME_LENGTH + 5];
        char sattr[MAX_SYSFS_ATTR_NAME_LENGTH];
        char *envp[] = { event, NULL };
        const char * const *templates;
        const char *template;
        int base;

        if (type >= ARRAY_SIZE(__templates))
                return -EINVAL;
        if (attr >= __templates_size[type])
                return -EINVAL;

        templates = __templates[type];
        template = templates[attr];

        base = hwmon_attr_base(type);

        scnprintf(sattr, MAX_SYSFS_ATTR_NAME_LENGTH, template, base + channel);
        scnprintf(event, sizeof(event), "NAME=%s", sattr);
        sysfs_notify(&dev->kobj, NULL, sattr);
        kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);

        if (type == hwmon_temp)
                hwmon_thermal_notify(dev, channel);

        return 0;
}
EXPORT_SYMBOL_GPL(hwmon_notify_event);

void hwmon_lock(struct device *dev)
{
        struct hwmon_device *hwdev = to_hwmon_device(dev);

        mutex_lock(&hwdev->lock);
}
EXPORT_SYMBOL_GPL(hwmon_lock);

void hwmon_unlock(struct device *dev)
{
        struct hwmon_device *hwdev = to_hwmon_device(dev);

        mutex_unlock(&hwdev->lock);
}
EXPORT_SYMBOL_GPL(hwmon_unlock);

static int hwmon_num_channel_attrs(const struct hwmon_channel_info *info)
{
        int i, n;

        for (i = n = 0; info->config[i]; i++)
                n += hweight32(info->config[i]);

        return n;
}

static int hwmon_genattrs(const void *drvdata,
                          struct attribute **attrs,
                          const struct hwmon_ops *ops,
                          const struct hwmon_channel_info *info)
{
        const char * const *templates;
        int template_size;
        int i, aindex = 0;

        if (info->type >= ARRAY_SIZE(__templates))
                return -EINVAL;

        templates = __templates[info->type];
        template_size = __templates_size[info->type];

        for (i = 0; info->config[i]; i++) {
                u32 attr_mask = info->config[i];
                u32 attr;

                while (attr_mask) {
                        struct attribute *a;

                        attr = __ffs(attr_mask);
                        attr_mask &= ~BIT(attr);
                        if (attr >= template_size || !templates[attr])
                                continue;       /* attribute is invisible */
                        a = hwmon_genattr(drvdata, info->type, attr, i,
                                          templates[attr], ops);
                        if (IS_ERR(a)) {
                                if (PTR_ERR(a) != -ENOENT)
                                        return PTR_ERR(a);
                                continue;
                        }
                        attrs[aindex++] = a;
                }
        }
        return aindex;
}

static struct attribute **
__hwmon_create_attrs(const void *drvdata, const struct hwmon_chip_info *chip)
{
        int ret, i, aindex = 0, nattrs = 0;
        struct attribute **attrs;

        for (i = 0; chip->info[i]; i++)
                nattrs += hwmon_num_channel_attrs(chip->info[i]);

        if (nattrs == 0)
                return ERR_PTR(-EINVAL);

        attrs = kzalloc_objs(*attrs, nattrs + 1);
        if (!attrs)
                return ERR_PTR(-ENOMEM);

        for (i = 0; chip->info[i]; i++) {
                ret = hwmon_genattrs(drvdata, &attrs[aindex], chip->ops,
                                     chip->info[i]);
                if (ret < 0) {
                        hwmon_free_attrs(attrs);
                        return ERR_PTR(ret);
                }
                aindex += ret;
        }

        return attrs;
}

static struct device *
__hwmon_device_register(struct device *dev, const char *name, void *drvdata,
                        const struct hwmon_chip_info *chip,
                        const struct attribute_group **groups)
{
        struct hwmon_device *hwdev;
        const char *label;
        struct device *hdev;
        struct device *tdev = dev;
        int i, err, id;

        /* Complain about invalid characters in hwmon name attribute */
        if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
                dev_warn(dev,
                         "hwmon: '%s' is not a valid name attribute, please fix\n",
                         name);

        id = ida_alloc(&hwmon_ida, GFP_KERNEL);
        if (id < 0)
                return ERR_PTR(id);

        hwdev = kzalloc_obj(*hwdev);
        if (hwdev == NULL) {
                err = -ENOMEM;
                goto ida_remove;
        }

        hdev = &hwdev->dev;

        if (chip) {
                struct attribute **attrs;
                int ngroups = 2; /* terminating NULL plus &hwdev->groups */

                if (groups)
                        for (i = 0; groups[i]; i++)
                                ngroups++;

                hwdev->groups = kzalloc_objs(*groups, ngroups);
                if (!hwdev->groups) {
                        err = -ENOMEM;
                        goto free_hwmon;
                }

                attrs = __hwmon_create_attrs(drvdata, chip);
                if (IS_ERR(attrs)) {
                        err = PTR_ERR(attrs);
                        goto free_hwmon;
                }

                hwdev->group.attrs = attrs;
                ngroups = 0;
                hwdev->groups[ngroups++] = &hwdev->group;

                if (groups) {
                        for (i = 0; groups[i]; i++)
                                hwdev->groups[ngroups++] = groups[i];
                }

                hdev->groups = hwdev->groups;
        } else {
                hdev->groups = groups;
        }

        if (dev && device_property_present(dev, "label")) {
                err = device_property_read_string(dev, "label", &label);
                if (err < 0)
                        goto free_hwmon;

                hwdev->label = kstrdup(label, GFP_KERNEL);
                if (hwdev->label == NULL) {
                        err = -ENOMEM;
                        goto free_hwmon;
                }
        }

        hwdev->name = name;
        hdev->class = &hwmon_class;
        hdev->parent = dev;
        while (tdev && !tdev->of_node)
                tdev = tdev->parent;
        hdev->of_node = tdev ? tdev->of_node : NULL;
        hwdev->chip = chip;
        mutex_init(&hwdev->lock);
        dev_set_drvdata(hdev, drvdata);
        dev_set_name(hdev, HWMON_ID_FORMAT, id);
        err = device_register(hdev);
        if (err) {
                put_device(hdev);
                goto ida_remove;
        }

        INIT_LIST_HEAD(&hwdev->tzdata);

        if (hdev->of_node && chip && chip->ops->read &&
            chip->info[0]->type == hwmon_chip) {
                u32 config = chip->info[0]->config[0];

                if (config & HWMON_C_REGISTER_TZ) {
                        err = hwmon_thermal_register_sensors(hdev);
                        if (err) {
                                device_unregister(hdev);
                                /*
                                 * Don't worry about hwdev; hwmon_dev_release(),
                                 * called from device_unregister(), will free it.
                                 */
                                goto ida_remove;
                        }
                }
                if (config & HWMON_C_PEC) {
                        err = hwmon_pec_register(hdev);
                        if (err) {
                                device_unregister(hdev);
                                goto ida_remove;
                        }
                }
        }

        return hdev;

free_hwmon:
        hwmon_dev_release(hdev);
ida_remove:
        ida_free(&hwmon_ida, id);
        return ERR_PTR(err);
}

/**
 * hwmon_device_register_with_groups - register w/ hwmon
 * @dev: the parent device
 * @name: hwmon name attribute
 * @drvdata: driver data to attach to created device
 * @groups: List of attribute groups to create
 *
 * hwmon_device_unregister() must be called when the device is no
 * longer needed.
 *
 * Returns the pointer to the new device.
 */
struct device *
hwmon_device_register_with_groups(struct device *dev, const char *name,
                                  void *drvdata,
                                  const struct attribute_group **groups)
{
        if (!name)
                return ERR_PTR(-EINVAL);

        return __hwmon_device_register(dev, name, drvdata, NULL, groups);
}
EXPORT_SYMBOL_GPL(hwmon_device_register_with_groups);

/**
 * hwmon_device_register_with_info - register w/ hwmon
 * @dev: the parent device (mandatory)
 * @name: hwmon name attribute (mandatory)
 * @drvdata: driver data to attach to created device (optional)
 * @chip: pointer to hwmon chip information (mandatory)
 * @extra_groups: pointer to list of additional non-standard attribute groups
 *      (optional)
 *
 * hwmon_device_unregister() must be called when the device is no
 * longer needed.
 *
 * Returns the pointer to the new device.
 */
struct device *
hwmon_device_register_with_info(struct device *dev, const char *name,
                                void *drvdata,
                                const struct hwmon_chip_info *chip,
                                const struct attribute_group **extra_groups)
{
        if (!dev || !name || !chip)
                return ERR_PTR(-EINVAL);

        if (!chip->ops || !(chip->ops->visible || chip->ops->is_visible) || !chip->info)
                return ERR_PTR(-EINVAL);

        return __hwmon_device_register(dev, name, drvdata, chip, extra_groups);
}
EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);

/**
 * hwmon_device_register_for_thermal - register hwmon device for thermal subsystem
 * @dev: the parent device
 * @name: hwmon name attribute
 * @drvdata: driver data to attach to created device
 *
 * The use of this function is restricted. It is provided for legacy reasons
 * and must only be called from the thermal subsystem.
 *
 * hwmon_device_unregister() must be called when the device is no
 * longer needed.
 *
 * Returns the pointer to the new device.
 */
struct device *
hwmon_device_register_for_thermal(struct device *dev, const char *name,
                                  void *drvdata)
{
        if (!name || !dev)
                return ERR_PTR(-EINVAL);

        return __hwmon_device_register(dev, name, drvdata, NULL, NULL);
}
EXPORT_SYMBOL_NS_GPL(hwmon_device_register_for_thermal, "HWMON_THERMAL");

/**
 * hwmon_device_register - register w/ hwmon
 * @dev: the device to register
 *
 * hwmon_device_unregister() must be called when the device is no
 * longer needed.
 *
 * Returns the pointer to the new device.
 */
struct device *hwmon_device_register(struct device *dev)
{
        dev_warn(dev,
                 "hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().\n");

        return __hwmon_device_register(dev, NULL, NULL, NULL, NULL);
}
EXPORT_SYMBOL_GPL(hwmon_device_register);

/**
 * hwmon_device_unregister - removes the previously registered class device
 *
 * @dev: the class device to destroy
 */
void hwmon_device_unregister(struct device *dev)
{
        int id;

        if (likely(sscanf(dev_name(dev), HWMON_ID_FORMAT, &id) == 1)) {
                device_unregister(dev);
                ida_free(&hwmon_ida, id);
        } else
                dev_dbg(dev->parent,
                        "hwmon_device_unregister() failed: bad class ID!\n");
}
EXPORT_SYMBOL_GPL(hwmon_device_unregister);

static void devm_hwmon_release(struct device *dev, void *res)
{
        struct device *hwdev = *(struct device **)res;

        hwmon_device_unregister(hwdev);
}

/**
 * devm_hwmon_device_register_with_groups - register w/ hwmon
 * @dev: the parent device
 * @name: hwmon name attribute
 * @drvdata: driver data to attach to created device
 * @groups: List of attribute groups to create
 *
 * Returns the pointer to the new device. The new device is automatically
 * unregistered with the parent device.
 */
struct device *
devm_hwmon_device_register_with_groups(struct device *dev, const char *name,
                                       void *drvdata,
                                       const struct attribute_group **groups)
{
        struct device **ptr, *hwdev;

        if (!dev)
                return ERR_PTR(-EINVAL);

        ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
        if (!ptr)
                return ERR_PTR(-ENOMEM);

        hwdev = hwmon_device_register_with_groups(dev, name, drvdata, groups);
        if (IS_ERR(hwdev))
                goto error;

        *ptr = hwdev;
        devres_add(dev, ptr);
        return hwdev;

error:
        devres_free(ptr);
        return hwdev;
}
EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_groups);

/**
 * devm_hwmon_device_register_with_info - register w/ hwmon
 * @dev:        the parent device
 * @name:       hwmon name attribute
 * @drvdata:    driver data to attach to created device
 * @chip:       pointer to hwmon chip information
 * @extra_groups: pointer to list of driver specific attribute groups
 *
 * Returns the pointer to the new device. The new device is automatically
 * unregistered with the parent device.
 */
struct device *
devm_hwmon_device_register_with_info(struct device *dev, const char *name,
                                     void *drvdata,
                                     const struct hwmon_chip_info *chip,
                                     const struct attribute_group **extra_groups)
{
        struct device **ptr, *hwdev;

        if (!dev)
                return ERR_PTR(-EINVAL);

        if (!name) {
                name = devm_hwmon_sanitize_name(dev, dev_name(dev));
                if (IS_ERR(name))
                        return ERR_CAST(name);
        }

        ptr = devres_alloc(devm_hwmon_release, sizeof(*ptr), GFP_KERNEL);
        if (!ptr)
                return ERR_PTR(-ENOMEM);

        hwdev = hwmon_device_register_with_info(dev, name, drvdata, chip,
                                                extra_groups);
        if (IS_ERR(hwdev))
                goto error;

        *ptr = hwdev;
        devres_add(dev, ptr);

        return hwdev;

error:
        devres_free(ptr);
        return hwdev;
}
EXPORT_SYMBOL_GPL(devm_hwmon_device_register_with_info);

static char *__hwmon_sanitize_name(struct device *dev, const char *old_name)
{
        char *name, *p;

        if (dev)
                name = devm_kstrdup(dev, old_name, GFP_KERNEL);
        else
                name = kstrdup(old_name, GFP_KERNEL);
        if (!name)
                return ERR_PTR(-ENOMEM);

        for (p = name; *p; p++)
                if (hwmon_is_bad_char(*p))
                        *p = '_';

        return name;
}

/**
 * hwmon_sanitize_name - Replaces invalid characters in a hwmon name
 * @name: NUL-terminated name
 *
 * Allocates a new string where any invalid characters will be replaced
 * by an underscore. It is the responsibility of the caller to release
 * the memory.
 *
 * Returns newly allocated name, or ERR_PTR on error.
 */
char *hwmon_sanitize_name(const char *name)
{
        if (!name)
                return ERR_PTR(-EINVAL);

        return __hwmon_sanitize_name(NULL, name);
}
EXPORT_SYMBOL_GPL(hwmon_sanitize_name);

/**
 * devm_hwmon_sanitize_name - resource managed hwmon_sanitize_name()
 * @dev: device to allocate memory for
 * @name: NUL-terminated name
 *
 * Allocates a new string where any invalid characters will be replaced
 * by an underscore.
 *
 * Returns newly allocated name, or ERR_PTR on error.
 */
char *devm_hwmon_sanitize_name(struct device *dev, const char *name)
{
        if (!dev || !name)
                return ERR_PTR(-EINVAL);

        return __hwmon_sanitize_name(dev, name);
}
EXPORT_SYMBOL_GPL(devm_hwmon_sanitize_name);

static void __init hwmon_pci_quirks(void)
{
#if defined CONFIG_X86 && defined CONFIG_PCI
        struct pci_dev *sb;
        u16 base;
        u8 enable;

        /* Open access to 0x295-0x296 on MSI MS-7031 */
        sb = pci_get_device(PCI_VENDOR_ID_ATI, 0x436c, NULL);
        if (sb) {
                if (sb->subsystem_vendor == 0x1462 &&   /* MSI */
                    sb->subsystem_device == 0x0031) {   /* MS-7031 */
                        pci_read_config_byte(sb, 0x48, &enable);
                        pci_read_config_word(sb, 0x64, &base);

                        if (base == 0 && !(enable & BIT(2))) {
                                dev_info(&sb->dev,
                                         "Opening wide generic port at 0x295\n");
                                pci_write_config_word(sb, 0x64, 0x295);
                                pci_write_config_byte(sb, 0x48,
                                                      enable | BIT(2));
                        }
                }
                pci_dev_put(sb);
        }
#endif
}

static int __init hwmon_init(void)
{
        int err;

        hwmon_pci_quirks();

        err = class_register(&hwmon_class);
        if (err) {
                pr_err("couldn't register hwmon sysfs class\n");
                return err;
        }
        return 0;
}

static void __exit hwmon_exit(void)
{
        class_unregister(&hwmon_class);
}

subsys_initcall(hwmon_init);
module_exit(hwmon_exit);

MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
MODULE_DESCRIPTION("hardware monitoring sysfs/class support");
MODULE_LICENSE("GPL");