nvec_power.c

Go to the documentation of this file.

/*
 * nvec_power: power supply driver for a NVIDIA compliant embedded controller
 *
 * Copyright (C) 2011 The AC100 Kernel Team <[email protected]>
 *
 * Authors:  Ilya Petrov <[email protected]>
 *           Marc Dietrich <[email protected]>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/power_supply.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/delay.h>

#include "nvec.h"

struct nvec_power {
    struct notifier_block notifier;
    struct delayed_work poller;
    struct nvec_chip *nvec;
    int on;
    int bat_present;
    int bat_status;
    int bat_voltage_now;
    int bat_current_now;
    int bat_current_avg;
    int time_remain;
    int charge_full_design;
    int charge_last_full;
    int critical_capacity;
    int capacity_remain;
    int bat_temperature;
    int bat_cap;
    int bat_type_enum;
    char bat_manu[30];
    char bat_model[30];
    char bat_type[30];
};

enum {
    SLOT_STATUS,
    VOLTAGE,
    TIME_REMAINING,
    CURRENT,
    AVERAGE_CURRENT,
    AVERAGING_TIME_INTERVAL,
    CAPACITY_REMAINING,
    LAST_FULL_CHARGE_CAPACITY,
    DESIGN_CAPACITY,
    CRITICAL_CAPACITY,
    TEMPERATURE,
    MANUFACTURER,
    MODEL,
    TYPE,
};

enum {
    AC,
    BAT,
};

struct bat_response {
    u8 event_type;
    u8 length;
    u8 sub_type;
    u8 status;
    /* payload */
    union {
        char plc[30];
        u16 plu;
        s16 pls;
    };
};

static struct power_supply nvec_bat_psy;
static struct power_supply nvec_psy;

static int nvec_power_notifier(struct notifier_block *nb,
                   unsigned long event_type, void *data)
{
    struct nvec_power *power =
        container_of(nb, struct nvec_power, notifier);
    struct bat_response *res = (struct bat_response *)data;

    if (event_type != NVEC_SYS)
        return NOTIFY_DONE;

    if (res->sub_type == 0) {
        if (power->on != res->plu) {
            power->on = res->plu;
            power_supply_changed(&nvec_psy);
        }
        return NOTIFY_STOP;
    }
    return NOTIFY_OK;
}

static const int bat_init[] = {
    LAST_FULL_CHARGE_CAPACITY, DESIGN_CAPACITY, CRITICAL_CAPACITY,
    MANUFACTURER, MODEL, TYPE,
};

static void get_bat_mfg_data(struct nvec_power *power)
{
    int i;
    char buf[] = { '\x02', '\x00' };

    for (i = 0; i < ARRAY_SIZE(bat_init); i++) {
        buf[1] = bat_init[i];
        nvec_write_async(power->nvec, buf, 2);
    }
}

static int nvec_power_bat_notifier(struct notifier_block *nb,
                   unsigned long event_type, void *data)
{
    struct nvec_power *power =
        container_of(nb, struct nvec_power, notifier);
    struct bat_response *res = (struct bat_response *)data;
    int status_changed = 0;

    if (event_type != NVEC_BAT)
        return NOTIFY_DONE;

    switch (res->sub_type) {
    case SLOT_STATUS:
        if (res->plc[0] & 1) {
            if (power->bat_present == 0) {
                status_changed = 1;
                get_bat_mfg_data(power);
            }

            power->bat_present = 1;

            switch ((res->plc[0] >> 1) & 3) {
            case 0:
                power->bat_status =
                    POWER_SUPPLY_STATUS_NOT_CHARGING;
                break;
            case 1:
                power->bat_status =
                    POWER_SUPPLY_STATUS_CHARGING;
                break;
            case 2:
                power->bat_status =
                    POWER_SUPPLY_STATUS_DISCHARGING;
                break;
            default:
                power->bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
            }
        } else {
            if (power->bat_present == 1)
                status_changed = 1;

            power->bat_present = 0;
            power->bat_status = POWER_SUPPLY_STATUS_UNKNOWN;
        }
        power->bat_cap = res->plc[1];
        if (status_changed)
            power_supply_changed(&nvec_bat_psy);
        break;
    case VOLTAGE:
        power->bat_voltage_now = res->plu * 1000;
        break;
    case TIME_REMAINING:
        power->time_remain = res->plu * 3600;
        break;
    case CURRENT:
        power->bat_current_now = res->pls * 1000;
        break;
    case AVERAGE_CURRENT:
        power->bat_current_avg = res->pls * 1000;
        break;
    case CAPACITY_REMAINING:
        power->capacity_remain = res->plu * 1000;
        break;
    case LAST_FULL_CHARGE_CAPACITY:
        power->charge_last_full = res->plu * 1000;
        break;
    case DESIGN_CAPACITY:
        power->charge_full_design = res->plu * 1000;
        break;
    case CRITICAL_CAPACITY:
        power->critical_capacity = res->plu * 1000;
        break;
    case TEMPERATURE:
        power->bat_temperature = res->plu - 2732;
        break;
    case MANUFACTURER:
        memcpy(power->bat_manu, &res->plc, res->length - 2);
        power->bat_model[res->length - 2] = '\0';
        break;
    case MODEL:
        memcpy(power->bat_model, &res->plc, res->length - 2);
        power->bat_model[res->length - 2] = '\0';
        break;
    case TYPE:
        memcpy(power->bat_type, &res->plc, res->length - 2);
        power->bat_type[res->length - 2] = '\0';
        /* this differs a little from the spec
           fill in more if you find some */
        if (!strncmp(power->bat_type, "Li", 30))
            power->bat_type_enum = POWER_SUPPLY_TECHNOLOGY_LION;
        else
            power->bat_type_enum = POWER_SUPPLY_TECHNOLOGY_UNKNOWN;
        break;
    default:
        return NOTIFY_STOP;
    }

    return NOTIFY_STOP;
}

static int nvec_power_get_property(struct power_supply *psy,
                   enum power_supply_property psp,
                   union power_supply_propval *val)
{
    struct nvec_power *power = dev_get_drvdata(psy->dev->parent);
    switch (psp) {
    case POWER_SUPPLY_PROP_ONLINE:
        val->intval = power->on;
        break;
    default:
        return -EINVAL;
    }
    return 0;
}

static int nvec_battery_get_property(struct power_supply *psy,
                     enum power_supply_property psp,
                     union power_supply_propval *val)
{
    struct nvec_power *power = dev_get_drvdata(psy->dev->parent);

    switch (psp) {
    case POWER_SUPPLY_PROP_STATUS:
        val->intval = power->bat_status;
        break;
    case POWER_SUPPLY_PROP_CAPACITY:
        val->intval = power->bat_cap;
        break;
    case POWER_SUPPLY_PROP_PRESENT:
        val->intval = power->bat_present;
        break;
    case POWER_SUPPLY_PROP_VOLTAGE_NOW:
        val->intval = power->bat_voltage_now;
        break;
    case POWER_SUPPLY_PROP_CURRENT_NOW:
        val->intval = power->bat_current_now;
        break;
    case POWER_SUPPLY_PROP_CURRENT_AVG:
        val->intval = power->bat_current_avg;
        break;
    case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
        val->intval = power->time_remain;
        break;
    case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
        val->intval = power->charge_full_design;
        break;
    case POWER_SUPPLY_PROP_CHARGE_FULL:
        val->intval = power->charge_last_full;
        break;
    case POWER_SUPPLY_PROP_CHARGE_EMPTY:
        val->intval = power->critical_capacity;
        break;
    case POWER_SUPPLY_PROP_CHARGE_NOW:
        val->intval = power->capacity_remain;
        break;
    case POWER_SUPPLY_PROP_TEMP:
        val->intval = power->bat_temperature;
        break;
    case POWER_SUPPLY_PROP_MANUFACTURER:
        val->strval = power->bat_manu;
        break;
    case POWER_SUPPLY_PROP_MODEL_NAME:
        val->strval = power->bat_model;
        break;
    case POWER_SUPPLY_PROP_TECHNOLOGY:
        val->intval = power->bat_type_enum;
        break;
    default:
        return -EINVAL;
    }
    return 0;
}

static enum power_supply_property nvec_power_props[] = {
    POWER_SUPPLY_PROP_ONLINE,
};

static enum power_supply_property nvec_battery_props[] = {
    POWER_SUPPLY_PROP_STATUS,
    POWER_SUPPLY_PROP_PRESENT,
    POWER_SUPPLY_PROP_CAPACITY,
    POWER_SUPPLY_PROP_VOLTAGE_NOW,
    POWER_SUPPLY_PROP_CURRENT_NOW,
#ifdef EC_FULL_DIAG
    POWER_SUPPLY_PROP_CURRENT_AVG,
    POWER_SUPPLY_PROP_TEMP,
    POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
#endif
    POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
    POWER_SUPPLY_PROP_CHARGE_FULL,
    POWER_SUPPLY_PROP_CHARGE_EMPTY,
    POWER_SUPPLY_PROP_CHARGE_NOW,
    POWER_SUPPLY_PROP_MANUFACTURER,
    POWER_SUPPLY_PROP_MODEL_NAME,
    POWER_SUPPLY_PROP_TECHNOLOGY,
};

static char *nvec_power_supplied_to[] = {
    "battery",
};

static struct power_supply nvec_bat_psy = {
    .name = "battery",
    .type = POWER_SUPPLY_TYPE_BATTERY,
    .properties = nvec_battery_props,
    .num_properties = ARRAY_SIZE(nvec_battery_props),
    .get_property = nvec_battery_get_property,
};

static struct power_supply nvec_psy = {
    .name = "ac",
    .type = POWER_SUPPLY_TYPE_MAINS,
    .supplied_to = nvec_power_supplied_to,
    .num_supplicants = ARRAY_SIZE(nvec_power_supplied_to),
    .properties = nvec_power_props,
    .num_properties = ARRAY_SIZE(nvec_power_props),
    .get_property = nvec_power_get_property,
};

static int counter;
static int const bat_iter[] = {
    SLOT_STATUS, VOLTAGE, CURRENT, CAPACITY_REMAINING,
#ifdef EC_FULL_DIAG
    AVERAGE_CURRENT, TEMPERATURE, TIME_REMAINING,
#endif
};

static void nvec_power_poll(struct work_struct *work)
{
    char buf[] = { '\x01', '\x00' };
    struct nvec_power *power = container_of(work, struct nvec_power,
                        poller.work);

    if (counter >= ARRAY_SIZE(bat_iter))
        counter = 0;

/* AC status via sys req */
    nvec_write_async(power->nvec, buf, 2);
    msleep(100);

/* select a battery request function via round robin
   doing it all at once seems to overload the power supply */
    buf[0] = '\x02';    /* battery */
    buf[1] = bat_iter[counter++];
    nvec_write_async(power->nvec, buf, 2);

    schedule_delayed_work(to_delayed_work(work), msecs_to_jiffies(5000));
};

static int __devinit nvec_power_probe(struct platform_device *pdev)
{
    struct power_supply *psy;
    struct nvec_power *power;
    struct nvec_chip *nvec = dev_get_drvdata(pdev->dev.parent);

    power = devm_kzalloc(&pdev->dev, sizeof(struct nvec_power), GFP_NOWAIT);
    if (power == NULL)
        return -ENOMEM;

    dev_set_drvdata(&pdev->dev, power);
    power->nvec = nvec;

    switch (pdev->id) {
    case AC:
        psy = &nvec_psy;

        power->notifier.notifier_call = nvec_power_notifier;

        INIT_DELAYED_WORK(&power->poller, nvec_power_poll);
        schedule_delayed_work(&power->poller, msecs_to_jiffies(5000));
        break;
    case BAT:
        psy = &nvec_bat_psy;

        power->notifier.notifier_call = nvec_power_bat_notifier;
        break;
    default:
        return -ENODEV;
    }

    nvec_register_notifier(nvec, &power->notifier, NVEC_SYS);

    if (pdev->id == BAT)
        get_bat_mfg_data(power);

    return power_supply_register(&pdev->dev, psy);
}

static int __devexit nvec_power_remove(struct platform_device *pdev)
{
    struct nvec_power *power = platform_get_drvdata(pdev);

    cancel_delayed_work_sync(&power->poller);
    switch (pdev->id) {
    case AC:
        power_supply_unregister(&nvec_psy);
        break;
    case BAT:
        power_supply_unregister(&nvec_bat_psy);
    }

    return 0;
}

static struct platform_driver nvec_power_driver = {
    .probe = nvec_power_probe,
    .remove = __devexit_p(nvec_power_remove),
    .driver = {
           .name = "nvec-power",
           .owner = THIS_MODULE,
           }
};

module_platform_driver(nvec_power_driver);

MODULE_AUTHOR("Ilya Petrov <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("NVEC battery and AC driver");
MODULE_ALIAS("platform:nvec-power");