pcf50633-charger.c

Go to the documentation of this file.

/* NXP PCF50633 Main Battery Charger Driver
 *
 * (C) 2006-2008 by Openmoko, Inc.
 * Author: Balaji Rao <[email protected]>
 * All rights reserved.
 *
 * Broken down from monstrous PCF50633 driver mainly by
 * Harald Welte, Andy Green and Werner Almesberger
 *
 *  This program is free software; you can redistribute  it and/or modify it
 *  under  the terms of  the GNU General  Public License as published by the
 *  Free Software Foundation;  either version 2 of the  License, or (at your
 *  option) any later version.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/sysfs.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>

#include <linux/mfd/pcf50633/core.h>
#include <linux/mfd/pcf50633/mbc.h>

struct pcf50633_mbc {
    struct pcf50633 *pcf;

    int adapter_online;
    int usb_online;

    struct power_supply usb;
    struct power_supply adapter;
    struct power_supply ac;
};

int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
{
    struct pcf50633_mbc *mbc = platform_get_drvdata(pcf->mbc_pdev);
    int ret = 0;
    u8 bits;
    int charging_start = 1;
    u8 mbcs2, chgmod;
    unsigned int mbcc5;

    if (ma >= 1000) {
        bits = PCF50633_MBCC7_USB_1000mA;
        ma = 1000;
    } else if (ma >= 500) {
        bits = PCF50633_MBCC7_USB_500mA;
        ma = 500;
    } else if (ma >= 100) {
        bits = PCF50633_MBCC7_USB_100mA;
        ma = 100;
    } else {
        bits = PCF50633_MBCC7_USB_SUSPEND;
        charging_start = 0;
        ma = 0;
    }

    ret = pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC7,
                    PCF50633_MBCC7_USB_MASK, bits);
    if (ret)
        dev_err(pcf->dev, "error setting usb curlim to %d mA\n", ma);
    else
        dev_info(pcf->dev, "usb curlim to %d mA\n", ma);

    /*
     * We limit the charging current to be the USB current limit.
     * The reason is that on pcf50633, when it enters PMU Standby mode,
     * which it does when the device goes "off", the USB current limit
     * reverts to the variant default.  In at least one common case, that
     * default is 500mA.  By setting the charging current to be the same
     * as the USB limit we set here before PMU standby, we enforce it only
     * using the correct amount of current even when the USB current limit
     * gets reset to the wrong thing
     */

    if (mbc->pcf->pdata->charger_reference_current_ma) {
        mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
        if (mbcc5 > 255)
            mbcc5 = 255;
        pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);
    }

    mbcs2 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2);
    chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);

    /* If chgmod == BATFULL, setting chgena has no effect.
     * Datasheet says we need to set resume instead but when autoresume is
     * used resume doesn't work. Clear and set chgena instead.
     */
    if (chgmod != PCF50633_MBCS2_MBC_BAT_FULL)
        pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,
                PCF50633_MBCC1_CHGENA, PCF50633_MBCC1_CHGENA);
    else {
        pcf50633_reg_clear_bits(pcf, PCF50633_REG_MBCC1,
                PCF50633_MBCC1_CHGENA);
        pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,
                PCF50633_MBCC1_CHGENA, PCF50633_MBCC1_CHGENA);
    }

    power_supply_changed(&mbc->usb);

    return ret;
}
EXPORT_SYMBOL_GPL(pcf50633_mbc_usb_curlim_set);

int pcf50633_mbc_get_status(struct pcf50633 *pcf)
{
    struct pcf50633_mbc *mbc  = platform_get_drvdata(pcf->mbc_pdev);
    int status = 0;
    u8 chgmod;

    if (!mbc)
        return 0;

    chgmod = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2)
        & PCF50633_MBCS2_MBC_MASK;

    if (mbc->usb_online)
        status |= PCF50633_MBC_USB_ONLINE;
    if (chgmod == PCF50633_MBCS2_MBC_USB_PRE ||
        chgmod == PCF50633_MBCS2_MBC_USB_PRE_WAIT ||
        chgmod == PCF50633_MBCS2_MBC_USB_FAST ||
        chgmod == PCF50633_MBCS2_MBC_USB_FAST_WAIT)
        status |= PCF50633_MBC_USB_ACTIVE;
    if (mbc->adapter_online)
        status |= PCF50633_MBC_ADAPTER_ONLINE;
    if (chgmod == PCF50633_MBCS2_MBC_ADP_PRE ||
        chgmod == PCF50633_MBCS2_MBC_ADP_PRE_WAIT ||
        chgmod == PCF50633_MBCS2_MBC_ADP_FAST ||
        chgmod == PCF50633_MBCS2_MBC_ADP_FAST_WAIT)
        status |= PCF50633_MBC_ADAPTER_ACTIVE;

    return status;
}
EXPORT_SYMBOL_GPL(pcf50633_mbc_get_status);

int pcf50633_mbc_get_usb_online_status(struct pcf50633 *pcf)
{
    struct pcf50633_mbc *mbc  = platform_get_drvdata(pcf->mbc_pdev);

    if (!mbc)
        return 0;

    return mbc->usb_online;
}
EXPORT_SYMBOL_GPL(pcf50633_mbc_get_usb_online_status);

static ssize_t
show_chgmode(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct pcf50633_mbc *mbc = dev_get_drvdata(dev);

    u8 mbcs2 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2);
    u8 chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);

    return sprintf(buf, "%d\n", chgmod);
}
static DEVICE_ATTR(chgmode, S_IRUGO, show_chgmode, NULL);

static ssize_t
show_usblim(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
    u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
                        PCF50633_MBCC7_USB_MASK;
    unsigned int ma;

    if (usblim == PCF50633_MBCC7_USB_1000mA)
        ma = 1000;
    else if (usblim == PCF50633_MBCC7_USB_500mA)
        ma = 500;
    else if (usblim == PCF50633_MBCC7_USB_100mA)
        ma = 100;
    else
        ma = 0;

    return sprintf(buf, "%u\n", ma);
}

static ssize_t set_usblim(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t count)
{
    struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
    unsigned long ma;
    int ret;

    ret = strict_strtoul(buf, 10, &ma);
    if (ret)
        return -EINVAL;

    pcf50633_mbc_usb_curlim_set(mbc->pcf, ma);

    return count;
}

static DEVICE_ATTR(usb_curlim, S_IRUGO | S_IWUSR, show_usblim, set_usblim);

static ssize_t
show_chglim(struct device *dev, struct device_attribute *attr, char *buf)
{
    struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
    u8 mbcc5 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC5);
    unsigned int ma;

    if (!mbc->pcf->pdata->charger_reference_current_ma)
        return -ENODEV;

    ma = (mbc->pcf->pdata->charger_reference_current_ma *  mbcc5) >> 8;

    return sprintf(buf, "%u\n", ma);
}

static ssize_t set_chglim(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t count)
{
    struct pcf50633_mbc *mbc = dev_get_drvdata(dev);
    unsigned long ma;
    unsigned int mbcc5;
    int ret;

    if (!mbc->pcf->pdata->charger_reference_current_ma)
        return -ENODEV;

    ret = strict_strtoul(buf, 10, &ma);
    if (ret)
        return -EINVAL;

    mbcc5 = (ma << 8) / mbc->pcf->pdata->charger_reference_current_ma;
    if (mbcc5 > 255)
        mbcc5 = 255;
    pcf50633_reg_write(mbc->pcf, PCF50633_REG_MBCC5, mbcc5);

    return count;
}

/*
 * This attribute allows to change MBC charging limit on the fly
 * independently of usb current limit. It also gets set automatically every
 * time usb current limit is changed.
 */
static DEVICE_ATTR(chg_curlim, S_IRUGO | S_IWUSR, show_chglim, set_chglim);

static struct attribute *pcf50633_mbc_sysfs_entries[] = {
    &dev_attr_chgmode.attr,
    &dev_attr_usb_curlim.attr,
    &dev_attr_chg_curlim.attr,
    NULL,
};

static struct attribute_group mbc_attr_group = {
    .name   = NULL,         /* put in device directory */
    .attrs  = pcf50633_mbc_sysfs_entries,
};

static void
pcf50633_mbc_irq_handler(int irq, void *data)
{
    struct pcf50633_mbc *mbc = data;

    /* USB */
    if (irq == PCF50633_IRQ_USBINS) {
        mbc->usb_online = 1;
    } else if (irq == PCF50633_IRQ_USBREM) {
        mbc->usb_online = 0;
        pcf50633_mbc_usb_curlim_set(mbc->pcf, 0);
    }

    /* Adapter */
    if (irq == PCF50633_IRQ_ADPINS)
        mbc->adapter_online = 1;
    else if (irq == PCF50633_IRQ_ADPREM)
        mbc->adapter_online = 0;

    power_supply_changed(&mbc->ac);
    power_supply_changed(&mbc->usb);
    power_supply_changed(&mbc->adapter);

    if (mbc->pcf->pdata->mbc_event_callback)
        mbc->pcf->pdata->mbc_event_callback(mbc->pcf, irq);
}

static int adapter_get_property(struct power_supply *psy,
            enum power_supply_property psp,
            union power_supply_propval *val)
{
    struct pcf50633_mbc *mbc = container_of(psy,
                struct pcf50633_mbc, adapter);
    int ret = 0;

    switch (psp) {
    case POWER_SUPPLY_PROP_ONLINE:
        val->intval =  mbc->adapter_online;
        break;
    default:
        ret = -EINVAL;
        break;
    }
    return ret;
}

static int usb_get_property(struct power_supply *psy,
            enum power_supply_property psp,
            union power_supply_propval *val)
{
    struct pcf50633_mbc *mbc = container_of(psy, struct pcf50633_mbc, usb);
    int ret = 0;
    u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
                        PCF50633_MBCC7_USB_MASK;

    switch (psp) {
    case POWER_SUPPLY_PROP_ONLINE:
        val->intval = mbc->usb_online &&
                (usblim <= PCF50633_MBCC7_USB_500mA);
        break;
    default:
        ret = -EINVAL;
        break;
    }
    return ret;
}

static int ac_get_property(struct power_supply *psy,
            enum power_supply_property psp,
            union power_supply_propval *val)
{
    struct pcf50633_mbc *mbc = container_of(psy, struct pcf50633_mbc, ac);
    int ret = 0;
    u8 usblim = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCC7) &
                        PCF50633_MBCC7_USB_MASK;

    switch (psp) {
    case POWER_SUPPLY_PROP_ONLINE:
        val->intval = mbc->usb_online &&
                (usblim == PCF50633_MBCC7_USB_1000mA);
        break;
    default:
        ret = -EINVAL;
        break;
    }
    return ret;
}

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

static const u8 mbc_irq_handlers[] = {
    PCF50633_IRQ_ADPINS,
    PCF50633_IRQ_ADPREM,
    PCF50633_IRQ_USBINS,
    PCF50633_IRQ_USBREM,
    PCF50633_IRQ_BATFULL,
    PCF50633_IRQ_CHGHALT,
    PCF50633_IRQ_THLIMON,
    PCF50633_IRQ_THLIMOFF,
    PCF50633_IRQ_USBLIMON,
    PCF50633_IRQ_USBLIMOFF,
    PCF50633_IRQ_LOWSYS,
    PCF50633_IRQ_LOWBAT,
};

static int __devinit pcf50633_mbc_probe(struct platform_device *pdev)
{
    struct pcf50633_mbc *mbc;
    int ret;
    int i;
    u8 mbcs1;

    mbc = kzalloc(sizeof(*mbc), GFP_KERNEL);
    if (!mbc)
        return -ENOMEM;

    platform_set_drvdata(pdev, mbc);
    mbc->pcf = dev_to_pcf50633(pdev->dev.parent);

    /* Set up IRQ handlers */
    for (i = 0; i < ARRAY_SIZE(mbc_irq_handlers); i++)
        pcf50633_register_irq(mbc->pcf, mbc_irq_handlers[i],
                    pcf50633_mbc_irq_handler, mbc);

    /* Create power supplies */
    mbc->adapter.name       = "adapter";
    mbc->adapter.type       = POWER_SUPPLY_TYPE_MAINS;
    mbc->adapter.properties     = power_props;
    mbc->adapter.num_properties = ARRAY_SIZE(power_props);
    mbc->adapter.get_property   = &adapter_get_property;
    mbc->adapter.supplied_to    = mbc->pcf->pdata->batteries;
    mbc->adapter.num_supplicants    = mbc->pcf->pdata->num_batteries;

    mbc->usb.name           = "usb";
    mbc->usb.type           = POWER_SUPPLY_TYPE_USB;
    mbc->usb.properties     = power_props;
    mbc->usb.num_properties     = ARRAY_SIZE(power_props);
    mbc->usb.get_property       = usb_get_property;
    mbc->usb.supplied_to        = mbc->pcf->pdata->batteries;
    mbc->usb.num_supplicants    = mbc->pcf->pdata->num_batteries;

    mbc->ac.name            = "ac";
    mbc->ac.type            = POWER_SUPPLY_TYPE_MAINS;
    mbc->ac.properties      = power_props;
    mbc->ac.num_properties      = ARRAY_SIZE(power_props);
    mbc->ac.get_property        = ac_get_property;
    mbc->ac.supplied_to     = mbc->pcf->pdata->batteries;
    mbc->ac.num_supplicants     = mbc->pcf->pdata->num_batteries;

    ret = power_supply_register(&pdev->dev, &mbc->adapter);
    if (ret) {
        dev_err(mbc->pcf->dev, "failed to register adapter\n");
        kfree(mbc);
        return ret;
    }

    ret = power_supply_register(&pdev->dev, &mbc->usb);
    if (ret) {
        dev_err(mbc->pcf->dev, "failed to register usb\n");
        power_supply_unregister(&mbc->adapter);
        kfree(mbc);
        return ret;
    }

    ret = power_supply_register(&pdev->dev, &mbc->ac);
    if (ret) {
        dev_err(mbc->pcf->dev, "failed to register ac\n");
        power_supply_unregister(&mbc->adapter);
        power_supply_unregister(&mbc->usb);
        kfree(mbc);
        return ret;
    }

    ret = sysfs_create_group(&pdev->dev.kobj, &mbc_attr_group);
    if (ret)
        dev_err(mbc->pcf->dev, "failed to create sysfs entries\n");

    mbcs1 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS1);
    if (mbcs1 & PCF50633_MBCS1_USBPRES)
        pcf50633_mbc_irq_handler(PCF50633_IRQ_USBINS, mbc);
    if (mbcs1 & PCF50633_MBCS1_ADAPTPRES)
        pcf50633_mbc_irq_handler(PCF50633_IRQ_ADPINS, mbc);

    return 0;
}

static int __devexit pcf50633_mbc_remove(struct platform_device *pdev)
{
    struct pcf50633_mbc *mbc = platform_get_drvdata(pdev);
    int i;

    /* Remove IRQ handlers */
    for (i = 0; i < ARRAY_SIZE(mbc_irq_handlers); i++)
        pcf50633_free_irq(mbc->pcf, mbc_irq_handlers[i]);

    sysfs_remove_group(&pdev->dev.kobj, &mbc_attr_group);
    power_supply_unregister(&mbc->usb);
    power_supply_unregister(&mbc->adapter);
    power_supply_unregister(&mbc->ac);

    kfree(mbc);

    return 0;
}

static struct platform_driver pcf50633_mbc_driver = {
    .driver = {
        .name = "pcf50633-mbc",
    },
    .probe = pcf50633_mbc_probe,
    .remove = __devexit_p(pcf50633_mbc_remove),
};

module_platform_driver(pcf50633_mbc_driver);

MODULE_AUTHOR("Balaji Rao <[email protected]>");
MODULE_DESCRIPTION("PCF50633 mbc driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:pcf50633-mbc");