tps65010.c

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/*
 * tps65010 - driver for tps6501x power management chips
 *
 * Copyright (C) 2004 Texas Instruments
 * Copyright (C) 2004-2005 David Brownell
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/workqueue.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>

#include <linux/i2c/tps65010.h>

#include <linux/gpio.h>


/*-------------------------------------------------------------------------*/

#define DRIVER_VERSION  "2 May 2005"
#define DRIVER_NAME (tps65010_driver.driver.name)

MODULE_DESCRIPTION("TPS6501x Power Management Driver");
MODULE_LICENSE("GPL");

static struct i2c_driver tps65010_driver;

/*-------------------------------------------------------------------------*/

/* This driver handles a family of multipurpose chips, which incorporate
 * voltage regulators, lithium ion/polymer battery charging, GPIOs, LEDs,
 * and other features often needed in portable devices like cell phones
 * or digital cameras.
 *
 * The tps65011 and tps65013 have different voltage settings compared
 * to tps65010 and tps65012.  The tps65013 has a NO_CHG status/irq.
 * All except tps65010 have "wait" mode, possibly defaulted so that
 * battery-insert != device-on.
 *
 * We could distinguish between some models by checking VDCDC1.UVLO or
 * other registers, unless they've been changed already after powerup
 * as part of board setup by a bootloader.
 */
enum tps_model {
    TPS65010,
    TPS65011,
    TPS65012,
    TPS65013,
};

struct tps65010 {
    struct i2c_client   *client;
    struct mutex        lock;
    struct delayed_work work;
    struct dentry       *file;
    unsigned        charging:1;
    unsigned        por:1;
    unsigned        model:8;
    u16         vbus;
    unsigned long       flags;
#define FLAG_VBUS_CHANGED   0
#define FLAG_IRQ_ENABLE     1

    /* copies of last register state */
    u8          chgstatus, regstatus, chgconf;
    u8          nmask1, nmask2;

    u8          outmask;
    struct gpio_chip    chip;
    struct platform_device  *leds;
};

#define POWER_POLL_DELAY    msecs_to_jiffies(5000)

/*-------------------------------------------------------------------------*/

#if defined(DEBUG) || defined(CONFIG_DEBUG_FS)

static void dbg_chgstat(char *buf, size_t len, u8 chgstatus)
{
    snprintf(buf, len, "%02x%s%s%s%s%s%s%s%s\n",
        chgstatus,
        (chgstatus & TPS_CHG_USB) ? " USB" : "",
        (chgstatus & TPS_CHG_AC) ? " AC" : "",
        (chgstatus & TPS_CHG_THERM) ? " therm" : "",
        (chgstatus & TPS_CHG_TERM) ? " done" :
            ((chgstatus & (TPS_CHG_USB|TPS_CHG_AC))
                ? " (charging)" : ""),
        (chgstatus & TPS_CHG_TAPER_TMO) ? " taper_tmo" : "",
        (chgstatus & TPS_CHG_CHG_TMO) ? " charge_tmo" : "",
        (chgstatus & TPS_CHG_PRECHG_TMO) ? " prechg_tmo" : "",
        (chgstatus & TPS_CHG_TEMP_ERR) ? " temp_err" : "");
}

static void dbg_regstat(char *buf, size_t len, u8 regstatus)
{
    snprintf(buf, len, "%02x %s%s%s%s%s%s%s%s\n",
        regstatus,
        (regstatus & TPS_REG_ONOFF) ? "off" : "(on)",
        (regstatus & TPS_REG_COVER) ? " uncover" : "",
        (regstatus & TPS_REG_UVLO) ? " UVLO" : "",
        (regstatus & TPS_REG_NO_CHG) ? " NO_CHG" : "",
        (regstatus & TPS_REG_PG_LD02) ? " ld02_bad" : "",
        (regstatus & TPS_REG_PG_LD01) ? " ld01_bad" : "",
        (regstatus & TPS_REG_PG_MAIN) ? " main_bad" : "",
        (regstatus & TPS_REG_PG_CORE) ? " core_bad" : "");
}

static void dbg_chgconf(int por, char *buf, size_t len, u8 chgconfig)
{
    const char *hibit;

    if (por)
        hibit = (chgconfig & TPS_CHARGE_POR)
                ? "POR=69ms" : "POR=1sec";
    else
        hibit = (chgconfig & TPS65013_AUA) ? "AUA" : "";

    snprintf(buf, len, "%02x %s%s%s AC=%d%% USB=%dmA %sCharge\n",
        chgconfig, hibit,
        (chgconfig & TPS_CHARGE_RESET) ? " reset" : "",
        (chgconfig & TPS_CHARGE_FAST) ? " fast" : "",
        ({int p; switch ((chgconfig >> 3) & 3) {
        case 3:     p = 100; break;
        case 2:     p = 75; break;
        case 1:     p = 50; break;
        default:    p = 25; break;
        }; p; }),
        (chgconfig & TPS_VBUS_CHARGING)
            ? ((chgconfig & TPS_VBUS_500MA) ? 500 : 100)
            : 0,
        (chgconfig & TPS_CHARGE_ENABLE) ? "" : "No");
}

#endif

#ifdef  DEBUG

static void show_chgstatus(const char *label, u8 chgstatus)
{
    char buf [100];

    dbg_chgstat(buf, sizeof buf, chgstatus);
    pr_debug("%s: %s %s", DRIVER_NAME, label, buf);
}

static void show_regstatus(const char *label, u8 regstatus)
{
    char buf [100];

    dbg_regstat(buf, sizeof buf, regstatus);
    pr_debug("%s: %s %s", DRIVER_NAME, label, buf);
}

static void show_chgconfig(int por, const char *label, u8 chgconfig)
{
    char buf [100];

    dbg_chgconf(por, buf, sizeof buf, chgconfig);
    pr_debug("%s: %s %s", DRIVER_NAME, label, buf);
}

#else

static inline void show_chgstatus(const char *label, u8 chgstatus) { }
static inline void show_regstatus(const char *label, u8 chgstatus) { }
static inline void show_chgconfig(int por, const char *label, u8 chgconfig) { }

#endif

#ifdef  CONFIG_DEBUG_FS

static int dbg_show(struct seq_file *s, void *_)
{
    struct tps65010 *tps = s->private;
    u8      value, v2;
    unsigned    i;
    char        buf[100];
    const char  *chip;

    switch (tps->model) {
    case TPS65010:  chip = "tps65010"; break;
    case TPS65011:  chip = "tps65011"; break;
    case TPS65012:  chip = "tps65012"; break;
    case TPS65013:  chip = "tps65013"; break;
    default:    chip = NULL; break;
    }
    seq_printf(s, "driver  %s\nversion %s\nchip    %s\n\n",
            DRIVER_NAME, DRIVER_VERSION, chip);

    mutex_lock(&tps->lock);

    /* FIXME how can we tell whether a battery is present?
     * likely involves a charge gauging chip (like BQ26501).
     */

    seq_printf(s, "%scharging\n\n", tps->charging ? "" : "(not) ");


    /* registers for monitoring battery charging and status; note
     * that reading chgstat and regstat may ack IRQs...
     */
    value = i2c_smbus_read_byte_data(tps->client, TPS_CHGCONFIG);
    dbg_chgconf(tps->por, buf, sizeof buf, value);
    seq_printf(s, "chgconfig %s", buf);

    value = i2c_smbus_read_byte_data(tps->client, TPS_CHGSTATUS);
    dbg_chgstat(buf, sizeof buf, value);
    seq_printf(s, "chgstat   %s", buf);
    value = i2c_smbus_read_byte_data(tps->client, TPS_MASK1);
    dbg_chgstat(buf, sizeof buf, value);
    seq_printf(s, "mask1     %s", buf);
    /* ignore ackint1 */

    value = i2c_smbus_read_byte_data(tps->client, TPS_REGSTATUS);
    dbg_regstat(buf, sizeof buf, value);
    seq_printf(s, "regstat   %s", buf);
    value = i2c_smbus_read_byte_data(tps->client, TPS_MASK2);
    dbg_regstat(buf, sizeof buf, value);
    seq_printf(s, "mask2     %s\n", buf);
    /* ignore ackint2 */

    schedule_delayed_work(&tps->work, POWER_POLL_DELAY);


    /* VMAIN voltage, enable lowpower, etc */
    value = i2c_smbus_read_byte_data(tps->client, TPS_VDCDC1);
    seq_printf(s, "vdcdc1    %02x\n", value);

    /* VCORE voltage, vibrator on/off */
    value = i2c_smbus_read_byte_data(tps->client, TPS_VDCDC2);
    seq_printf(s, "vdcdc2    %02x\n", value);

    /* both LD0s, and their lowpower behavior */
    value = i2c_smbus_read_byte_data(tps->client, TPS_VREGS1);
    seq_printf(s, "vregs1    %02x\n\n", value);


    /* LEDs and GPIOs */
    value = i2c_smbus_read_byte_data(tps->client, TPS_LED1_ON);
    v2 = i2c_smbus_read_byte_data(tps->client, TPS_LED1_PER);
    seq_printf(s, "led1 %s, on=%02x, per=%02x, %d/%d msec\n",
        (value & 0x80)
            ? ((v2 & 0x80) ? "on" : "off")
            : ((v2 & 0x80) ? "blink" : "(nPG)"),
        value, v2,
        (value & 0x7f) * 10, (v2 & 0x7f) * 100);

    value = i2c_smbus_read_byte_data(tps->client, TPS_LED2_ON);
    v2 = i2c_smbus_read_byte_data(tps->client, TPS_LED2_PER);
    seq_printf(s, "led2 %s, on=%02x, per=%02x, %d/%d msec\n",
        (value & 0x80)
            ? ((v2 & 0x80) ? "on" : "off")
            : ((v2 & 0x80) ? "blink" : "off"),
        value, v2,
        (value & 0x7f) * 10, (v2 & 0x7f) * 100);

    value = i2c_smbus_read_byte_data(tps->client, TPS_DEFGPIO);
    v2 = i2c_smbus_read_byte_data(tps->client, TPS_MASK3);
    seq_printf(s, "defgpio %02x mask3 %02x\n", value, v2);

    for (i = 0; i < 4; i++) {
        if (value & (1 << (4 + i)))
            seq_printf(s, "  gpio%d-out %s\n", i + 1,
                (value & (1 << i)) ? "low" : "hi ");
        else
            seq_printf(s, "  gpio%d-in  %s %s %s\n", i + 1,
                (value & (1 << i)) ? "hi " : "low",
                (v2 & (1 << i)) ? "no-irq" : "irq",
                (v2 & (1 << (4 + i))) ? "rising" : "falling");
    }

    mutex_unlock(&tps->lock);
    return 0;
}

static int dbg_tps_open(struct inode *inode, struct file *file)
{
    return single_open(file, dbg_show, inode->i_private);
}

static const struct file_operations debug_fops = {
    .open       = dbg_tps_open,
    .read       = seq_read,
    .llseek     = seq_lseek,
    .release    = single_release,
};

#define DEBUG_FOPS  &debug_fops

#else
#define DEBUG_FOPS  NULL
#endif

/*-------------------------------------------------------------------------*/

/* handle IRQS in a task context, so we can use I2C calls */
static void tps65010_interrupt(struct tps65010 *tps)
{
    u8 tmp = 0, mask, poll;

    /* IRQs won't trigger for certain events, but we can get
     * others by polling (normally, with external power applied).
     */
    poll = 0;

    /* regstatus irqs */
    if (tps->nmask2) {
        tmp = i2c_smbus_read_byte_data(tps->client, TPS_REGSTATUS);
        mask = tmp ^ tps->regstatus;
        tps->regstatus = tmp;
        mask &= tps->nmask2;
    } else
        mask = 0;
    if (mask) {
        tps->regstatus =  tmp;
        /* may need to shut something down ... */

        /* "off" usually means deep sleep */
        if (tmp & TPS_REG_ONOFF) {
            pr_info("%s: power off button\n", DRIVER_NAME);
#if 0
            /* REVISIT:  this might need its own workqueue
             * plus tweaks including deadlock avoidance ...
             * also needs to get error handling and probably
             * an #ifdef CONFIG_HIBERNATION
             */
            hibernate();
#endif
            poll = 1;
        }
    }

    /* chgstatus irqs */
    if (tps->nmask1) {
        tmp = i2c_smbus_read_byte_data(tps->client, TPS_CHGSTATUS);
        mask = tmp ^ tps->chgstatus;
        tps->chgstatus = tmp;
        mask &= tps->nmask1;
    } else
        mask = 0;
    if (mask) {
        unsigned    charging = 0;

        show_chgstatus("chg/irq", tmp);
        if (tmp & (TPS_CHG_USB|TPS_CHG_AC))
            show_chgconfig(tps->por, "conf", tps->chgconf);

        /* Unless it was turned off or disabled, we charge any
         * battery whenever there's power available for it
         * and the charger hasn't been disabled.
         */
        if (!(tps->chgstatus & ~(TPS_CHG_USB|TPS_CHG_AC))
                && (tps->chgstatus & (TPS_CHG_USB|TPS_CHG_AC))
                && (tps->chgconf & TPS_CHARGE_ENABLE)
                ) {
            if (tps->chgstatus & TPS_CHG_USB) {
                /* VBUS options are readonly until reconnect */
                if (mask & TPS_CHG_USB)
                    set_bit(FLAG_VBUS_CHANGED, &tps->flags);
                charging = 1;
            } else if (tps->chgstatus & TPS_CHG_AC)
                charging = 1;
        }
        if (charging != tps->charging) {
            tps->charging = charging;
            pr_info("%s: battery %scharging\n",
                DRIVER_NAME, charging ? "" :
                ((tps->chgstatus & (TPS_CHG_USB|TPS_CHG_AC))
                    ? "NOT " : "dis"));
        }
    }

    /* always poll to detect (a) power removal, without tps65013
     * NO_CHG IRQ; or (b) restart of charging after stop.
     */
    if ((tps->model != TPS65013 || !tps->charging)
            && (tps->chgstatus & (TPS_CHG_USB|TPS_CHG_AC)))
        poll = 1;
    if (poll)
        schedule_delayed_work(&tps->work, POWER_POLL_DELAY);

    /* also potentially gpio-in rise or fall */
}

/* handle IRQs and polling using keventd for now */
static void tps65010_work(struct work_struct *work)
{
    struct tps65010     *tps;

    tps = container_of(to_delayed_work(work), struct tps65010, work);
    mutex_lock(&tps->lock);

    tps65010_interrupt(tps);

    if (test_and_clear_bit(FLAG_VBUS_CHANGED, &tps->flags)) {
        int status;
        u8  chgconfig, tmp;

        chgconfig = i2c_smbus_read_byte_data(tps->client,
                    TPS_CHGCONFIG);
        chgconfig &= ~(TPS_VBUS_500MA | TPS_VBUS_CHARGING);
        if (tps->vbus == 500)
            chgconfig |= TPS_VBUS_500MA | TPS_VBUS_CHARGING;
        else if (tps->vbus >= 100)
            chgconfig |= TPS_VBUS_CHARGING;

        status = i2c_smbus_write_byte_data(tps->client,
                TPS_CHGCONFIG, chgconfig);

        /* vbus update fails unless VBUS is connected! */
        tmp = i2c_smbus_read_byte_data(tps->client, TPS_CHGCONFIG);
        tps->chgconf = tmp;
        show_chgconfig(tps->por, "update vbus", tmp);
    }

    if (test_and_clear_bit(FLAG_IRQ_ENABLE, &tps->flags))
        enable_irq(tps->client->irq);

    mutex_unlock(&tps->lock);
}

static irqreturn_t tps65010_irq(int irq, void *_tps)
{
    struct tps65010     *tps = _tps;

    disable_irq_nosync(irq);
    set_bit(FLAG_IRQ_ENABLE, &tps->flags);
    schedule_delayed_work(&tps->work, 0);
    return IRQ_HANDLED;
}

/*-------------------------------------------------------------------------*/

/* offsets 0..3 == GPIO1..GPIO4
 * offsets 4..5 == LED1/nPG, LED2 (we set one of the non-BLINK modes)
 * offset 6 == vibrator motor driver
 */
static void
tps65010_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
    if (offset < 4)
        tps65010_set_gpio_out_value(offset + 1, value);
    else if (offset < 6)
        tps65010_set_led(offset - 3, value ? ON : OFF);
    else
        tps65010_set_vib(value);
}

static int
tps65010_output(struct gpio_chip *chip, unsigned offset, int value)
{
    /* GPIOs may be input-only */
    if (offset < 4) {
        struct tps65010     *tps;

        tps = container_of(chip, struct tps65010, chip);
        if (!(tps->outmask & (1 << offset)))
            return -EINVAL;
        tps65010_set_gpio_out_value(offset + 1, value);
    } else if (offset < 6)
        tps65010_set_led(offset - 3, value ? ON : OFF);
    else
        tps65010_set_vib(value);

    return 0;
}

static int tps65010_gpio_get(struct gpio_chip *chip, unsigned offset)
{
    int         value;
    struct tps65010     *tps;

    tps = container_of(chip, struct tps65010, chip);

    if (offset < 4) {
        value = i2c_smbus_read_byte_data(tps->client, TPS_DEFGPIO);
        if (value < 0)
            return 0;
        if (value & (1 << (offset + 4)))    /* output */
            return !(value & (1 << offset));
        else                    /* input */
            return (value & (1 << offset));
    }

    /* REVISIT we *could* report LED1/nPG and LED2 state ... */
    return 0;
}


/*-------------------------------------------------------------------------*/

static struct tps65010 *the_tps;

static int __exit tps65010_remove(struct i2c_client *client)
{
    struct tps65010     *tps = i2c_get_clientdata(client);
    struct tps65010_board   *board = client->dev.platform_data;

    if (board && board->teardown) {
        int status = board->teardown(client, board->context);
        if (status < 0)
            dev_dbg(&client->dev, "board %s %s err %d\n",
                "teardown", client->name, status);
    }
    if (client->irq > 0)
        free_irq(client->irq, tps);
    cancel_delayed_work_sync(&tps->work);
    debugfs_remove(tps->file);
    kfree(tps);
    the_tps = NULL;
    return 0;
}

static int tps65010_probe(struct i2c_client *client,
              const struct i2c_device_id *id)
{
    struct tps65010     *tps;
    int         status;
    struct tps65010_board   *board = client->dev.platform_data;

    if (the_tps) {
        dev_dbg(&client->dev, "only one tps6501x chip allowed\n");
        return -ENODEV;
    }

    if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
        return -EINVAL;

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

    mutex_init(&tps->lock);
    INIT_DELAYED_WORK(&tps->work, tps65010_work);
    tps->client = client;
    tps->model = id->driver_data;

    /* the IRQ is active low, but many gpio lines can't support that
     * so this driver uses falling-edge triggers instead.
     */
    if (client->irq > 0) {
        status = request_irq(client->irq, tps65010_irq,
                     IRQF_TRIGGER_FALLING, DRIVER_NAME, tps);
        if (status < 0) {
            dev_dbg(&client->dev, "can't get IRQ %d, err %d\n",
                    client->irq, status);
            goto fail1;
        }
        /* annoying race here, ideally we'd have an option
         * to claim the irq now and enable it later.
         * FIXME genirq IRQF_NOAUTOEN now solves that ...
         */
        disable_irq(client->irq);
        set_bit(FLAG_IRQ_ENABLE, &tps->flags);
    } else
        dev_warn(&client->dev, "IRQ not configured!\n");


    switch (tps->model) {
    case TPS65010:
    case TPS65012:
        tps->por = 1;
        break;
    /* else CHGCONFIG.POR is replaced by AUA, enabling a WAIT mode */
    }
    tps->chgconf = i2c_smbus_read_byte_data(client, TPS_CHGCONFIG);
    show_chgconfig(tps->por, "conf/init", tps->chgconf);

    show_chgstatus("chg/init",
        i2c_smbus_read_byte_data(client, TPS_CHGSTATUS));
    show_regstatus("reg/init",
        i2c_smbus_read_byte_data(client, TPS_REGSTATUS));

    pr_debug("%s: vdcdc1 0x%02x, vdcdc2 %02x, vregs1 %02x\n", DRIVER_NAME,
        i2c_smbus_read_byte_data(client, TPS_VDCDC1),
        i2c_smbus_read_byte_data(client, TPS_VDCDC2),
        i2c_smbus_read_byte_data(client, TPS_VREGS1));
    pr_debug("%s: defgpio 0x%02x, mask3 0x%02x\n", DRIVER_NAME,
        i2c_smbus_read_byte_data(client, TPS_DEFGPIO),
        i2c_smbus_read_byte_data(client, TPS_MASK3));

    i2c_set_clientdata(client, tps);
    the_tps = tps;

#if defined(CONFIG_USB_GADGET) && !defined(CONFIG_USB_OTG)
    /* USB hosts can't draw VBUS.  OTG devices could, later
     * when OTG infrastructure enables it.  USB peripherals
     * could be relying on VBUS while booting, though.
     */
    tps->vbus = 100;
#endif

    /* unmask the "interesting" irqs, then poll once to
     * kickstart monitoring, initialize shadowed status
     * registers, and maybe disable VBUS draw.
     */
    tps->nmask1 = ~0;
    (void) i2c_smbus_write_byte_data(client, TPS_MASK1, ~tps->nmask1);

    tps->nmask2 = TPS_REG_ONOFF;
    if (tps->model == TPS65013)
        tps->nmask2 |= TPS_REG_NO_CHG;
    (void) i2c_smbus_write_byte_data(client, TPS_MASK2, ~tps->nmask2);

    (void) i2c_smbus_write_byte_data(client, TPS_MASK3, 0x0f
        | i2c_smbus_read_byte_data(client, TPS_MASK3));

    tps65010_work(&tps->work.work);

    tps->file = debugfs_create_file(DRIVER_NAME, S_IRUGO, NULL,
                tps, DEBUG_FOPS);

    /* optionally register GPIOs */
    if (board && board->base != 0) {
        tps->outmask = board->outmask;

        tps->chip.label = client->name;
        tps->chip.dev = &client->dev;
        tps->chip.owner = THIS_MODULE;

        tps->chip.set = tps65010_gpio_set;
        tps->chip.direction_output = tps65010_output;

        /* NOTE:  only partial support for inputs; nyet IRQs */
        tps->chip.get = tps65010_gpio_get;

        tps->chip.base = board->base;
        tps->chip.ngpio = 7;
        tps->chip.can_sleep = 1;

        status = gpiochip_add(&tps->chip);
        if (status < 0)
            dev_err(&client->dev, "can't add gpiochip, err %d\n",
                    status);
        else if (board->setup) {
            status = board->setup(client, board->context);
            if (status < 0) {
                dev_dbg(&client->dev,
                    "board %s %s err %d\n",
                    "setup", client->name, status);
                status = 0;
            }
        }
    }

    return 0;
fail1:
    kfree(tps);
    return status;
}

static const struct i2c_device_id tps65010_id[] = {
    { "tps65010", TPS65010 },
    { "tps65011", TPS65011 },
    { "tps65012", TPS65012 },
    { "tps65013", TPS65013 },
    { "tps65014", TPS65011 },   /* tps65011 charging at 6.5V max */
    { }
};
MODULE_DEVICE_TABLE(i2c, tps65010_id);

static struct i2c_driver tps65010_driver = {
    .driver = {
        .name   = "tps65010",
    },
    .probe  = tps65010_probe,
    .remove = __exit_p(tps65010_remove),
    .id_table = tps65010_id,
};

/*-------------------------------------------------------------------------*/

/* Draw from VBUS:
 *   0 mA -- DON'T DRAW (might supply power instead)
 * 100 mA -- usb unit load (slowest charge rate)
 * 500 mA -- usb high power (fast battery charge)
 */
int tps65010_set_vbus_draw(unsigned mA)
{
    unsigned long   flags;

    if (!the_tps)
        return -ENODEV;

    /* assumes non-SMP */
    local_irq_save(flags);
    if (mA >= 500)
        mA = 500;
    else if (mA >= 100)
        mA = 100;
    else
        mA = 0;
    the_tps->vbus = mA;
    if ((the_tps->chgstatus & TPS_CHG_USB)
            && test_and_set_bit(
                FLAG_VBUS_CHANGED, &the_tps->flags)) {
        /* gadget drivers call this in_irq() */
        schedule_delayed_work(&the_tps->work, 0);
    }
    local_irq_restore(flags);

    return 0;
}
EXPORT_SYMBOL(tps65010_set_vbus_draw);

/*-------------------------------------------------------------------------*/
/* tps65010_set_gpio_out_value parameter:
 * gpio:  GPIO1, GPIO2, GPIO3 or GPIO4
 * value: LOW or HIGH
 */
int tps65010_set_gpio_out_value(unsigned gpio, unsigned value)
{
    int  status;
    unsigned defgpio;

    if (!the_tps)
        return -ENODEV;
    if ((gpio < GPIO1) || (gpio > GPIO4))
        return -EINVAL;

    mutex_lock(&the_tps->lock);

    defgpio = i2c_smbus_read_byte_data(the_tps->client, TPS_DEFGPIO);

    /* Configure GPIO for output */
    defgpio |= 1 << (gpio + 3);

    /* Writing 1 forces a logic 0 on that GPIO and vice versa */
    switch (value) {
    case LOW:
        defgpio |= 1 << (gpio - 1);    /* set GPIO low by writing 1 */
        break;
    /* case HIGH: */
    default:
        defgpio &= ~(1 << (gpio - 1)); /* set GPIO high by writing 0 */
        break;
    }

    status = i2c_smbus_write_byte_data(the_tps->client,
        TPS_DEFGPIO, defgpio);

    pr_debug("%s: gpio%dout = %s, defgpio 0x%02x\n", DRIVER_NAME,
        gpio, value ? "high" : "low",
        i2c_smbus_read_byte_data(the_tps->client, TPS_DEFGPIO));

    mutex_unlock(&the_tps->lock);
    return status;
}
EXPORT_SYMBOL(tps65010_set_gpio_out_value);

/*-------------------------------------------------------------------------*/
/* tps65010_set_led parameter:
 * led:  LED1 or LED2
 * mode: ON, OFF or BLINK
 */
int tps65010_set_led(unsigned led, unsigned mode)
{
    int  status;
    unsigned led_on, led_per, offs;

    if (!the_tps)
        return -ENODEV;

    if (led == LED1)
        offs = 0;
    else {
        offs = 2;
        led = LED2;
    }

    mutex_lock(&the_tps->lock);

    pr_debug("%s: led%i_on   0x%02x\n", DRIVER_NAME, led,
        i2c_smbus_read_byte_data(the_tps->client,
                TPS_LED1_ON + offs));

    pr_debug("%s: led%i_per  0x%02x\n", DRIVER_NAME, led,
        i2c_smbus_read_byte_data(the_tps->client,
                TPS_LED1_PER + offs));

    switch (mode) {
    case OFF:
        led_on  = 1 << 7;
        led_per = 0 << 7;
        break;
    case ON:
        led_on  = 1 << 7;
        led_per = 1 << 7;
        break;
    case BLINK:
        led_on  = 0x30 | (0 << 7);
        led_per = 0x08 | (1 << 7);
        break;
    default:
        printk(KERN_ERR "%s: Wrong mode parameter for set_led()\n",
               DRIVER_NAME);
        mutex_unlock(&the_tps->lock);
        return -EINVAL;
    }

    status = i2c_smbus_write_byte_data(the_tps->client,
            TPS_LED1_ON + offs, led_on);

    if (status != 0) {
        printk(KERN_ERR "%s: Failed to write led%i_on register\n",
               DRIVER_NAME, led);
        mutex_unlock(&the_tps->lock);
        return status;
    }

    pr_debug("%s: led%i_on   0x%02x\n", DRIVER_NAME, led,
        i2c_smbus_read_byte_data(the_tps->client, TPS_LED1_ON + offs));

    status = i2c_smbus_write_byte_data(the_tps->client,
            TPS_LED1_PER + offs, led_per);

    if (status != 0) {
        printk(KERN_ERR "%s: Failed to write led%i_per register\n",
               DRIVER_NAME, led);
        mutex_unlock(&the_tps->lock);
        return status;
    }

    pr_debug("%s: led%i_per  0x%02x\n", DRIVER_NAME, led,
        i2c_smbus_read_byte_data(the_tps->client,
                TPS_LED1_PER + offs));

    mutex_unlock(&the_tps->lock);

    return status;
}
EXPORT_SYMBOL(tps65010_set_led);

/*-------------------------------------------------------------------------*/
/* tps65010_set_vib parameter:
 * value: ON or OFF
 */
int tps65010_set_vib(unsigned value)
{
    int  status;
    unsigned vdcdc2;

    if (!the_tps)
        return -ENODEV;

    mutex_lock(&the_tps->lock);

    vdcdc2 = i2c_smbus_read_byte_data(the_tps->client, TPS_VDCDC2);
    vdcdc2 &= ~(1 << 1);
    if (value)
        vdcdc2 |= (1 << 1);
    status = i2c_smbus_write_byte_data(the_tps->client,
        TPS_VDCDC2, vdcdc2);

    pr_debug("%s: vibrator %s\n", DRIVER_NAME, value ? "on" : "off");

    mutex_unlock(&the_tps->lock);
    return status;
}
EXPORT_SYMBOL(tps65010_set_vib);

/*-------------------------------------------------------------------------*/
/* tps65010_set_low_pwr parameter:
 * mode: ON or OFF
 */
int tps65010_set_low_pwr(unsigned mode)
{
    int  status;
    unsigned vdcdc1;

    if (!the_tps)
        return -ENODEV;

    mutex_lock(&the_tps->lock);

    pr_debug("%s: %s low_pwr, vdcdc1 0x%02x\n", DRIVER_NAME,
        mode ? "enable" : "disable",
        i2c_smbus_read_byte_data(the_tps->client, TPS_VDCDC1));

    vdcdc1 = i2c_smbus_read_byte_data(the_tps->client, TPS_VDCDC1);

    switch (mode) {
    case OFF:
        vdcdc1 &= ~TPS_ENABLE_LP; /* disable ENABLE_LP bit */
        break;
    /* case ON: */
    default:
        vdcdc1 |= TPS_ENABLE_LP;  /* enable ENABLE_LP bit */
        break;
    }

    status = i2c_smbus_write_byte_data(the_tps->client,
            TPS_VDCDC1, vdcdc1);

    if (status != 0)
        printk(KERN_ERR "%s: Failed to write vdcdc1 register\n",
            DRIVER_NAME);
    else
        pr_debug("%s: vdcdc1 0x%02x\n", DRIVER_NAME,
            i2c_smbus_read_byte_data(the_tps->client, TPS_VDCDC1));

    mutex_unlock(&the_tps->lock);

    return status;
}
EXPORT_SYMBOL(tps65010_set_low_pwr);

/*-------------------------------------------------------------------------*/
/* tps65010_config_vregs1 parameter:
 * value to be written to VREGS1 register
 * Note: The complete register is written, set all bits you need
 */
int tps65010_config_vregs1(unsigned value)
{
    int  status;

    if (!the_tps)
        return -ENODEV;

    mutex_lock(&the_tps->lock);

    pr_debug("%s: vregs1 0x%02x\n", DRIVER_NAME,
            i2c_smbus_read_byte_data(the_tps->client, TPS_VREGS1));

    status = i2c_smbus_write_byte_data(the_tps->client,
            TPS_VREGS1, value);

    if (status != 0)
        printk(KERN_ERR "%s: Failed to write vregs1 register\n",
            DRIVER_NAME);
    else
        pr_debug("%s: vregs1 0x%02x\n", DRIVER_NAME,
            i2c_smbus_read_byte_data(the_tps->client, TPS_VREGS1));

    mutex_unlock(&the_tps->lock);

    return status;
}
EXPORT_SYMBOL(tps65010_config_vregs1);

int tps65010_config_vdcdc2(unsigned value)
{
    struct i2c_client *c;
    int  status;

    if (!the_tps)
        return -ENODEV;

    c = the_tps->client;
    mutex_lock(&the_tps->lock);

    pr_debug("%s: vdcdc2 0x%02x\n", DRIVER_NAME,
         i2c_smbus_read_byte_data(c, TPS_VDCDC2));

    status = i2c_smbus_write_byte_data(c, TPS_VDCDC2, value);

    if (status != 0)
        printk(KERN_ERR "%s: Failed to write vdcdc2 register\n",
            DRIVER_NAME);
    else
        pr_debug("%s: vregs1 0x%02x\n", DRIVER_NAME,
             i2c_smbus_read_byte_data(c, TPS_VDCDC2));

    mutex_unlock(&the_tps->lock);
    return status;
}
EXPORT_SYMBOL(tps65010_config_vdcdc2);

/*-------------------------------------------------------------------------*/
/* tps65013_set_low_pwr parameter:
 * mode: ON or OFF
 */

/* FIXME: Assumes AC or USB power is present. Setting AUA bit is not
    required if power supply is through a battery */

int tps65013_set_low_pwr(unsigned mode)
{
    int  status;
    unsigned vdcdc1, chgconfig;

    if (!the_tps || the_tps->por)
        return -ENODEV;

    mutex_lock(&the_tps->lock);

    pr_debug("%s: %s low_pwr, chgconfig 0x%02x vdcdc1 0x%02x\n",
        DRIVER_NAME,
        mode ? "enable" : "disable",
        i2c_smbus_read_byte_data(the_tps->client, TPS_CHGCONFIG),
        i2c_smbus_read_byte_data(the_tps->client, TPS_VDCDC1));

    chgconfig = i2c_smbus_read_byte_data(the_tps->client, TPS_CHGCONFIG);
    vdcdc1 = i2c_smbus_read_byte_data(the_tps->client, TPS_VDCDC1);

    switch (mode) {
    case OFF:
        chgconfig &= ~TPS65013_AUA; /* disable AUA bit */
        vdcdc1 &= ~TPS_ENABLE_LP; /* disable ENABLE_LP bit */
        break;
    /* case ON: */
    default:
        chgconfig |= TPS65013_AUA;  /* enable AUA bit */
        vdcdc1 |= TPS_ENABLE_LP;  /* enable ENABLE_LP bit */
        break;
    }

    status = i2c_smbus_write_byte_data(the_tps->client,
            TPS_CHGCONFIG, chgconfig);
    if (status != 0) {
        printk(KERN_ERR "%s: Failed to write chconfig register\n",
     DRIVER_NAME);
        mutex_unlock(&the_tps->lock);
        return status;
    }

    chgconfig = i2c_smbus_read_byte_data(the_tps->client, TPS_CHGCONFIG);
    the_tps->chgconf = chgconfig;
    show_chgconfig(0, "chgconf", chgconfig);

    status = i2c_smbus_write_byte_data(the_tps->client,
            TPS_VDCDC1, vdcdc1);

    if (status != 0)
        printk(KERN_ERR "%s: Failed to write vdcdc1 register\n",
     DRIVER_NAME);
    else
        pr_debug("%s: vdcdc1 0x%02x\n", DRIVER_NAME,
            i2c_smbus_read_byte_data(the_tps->client, TPS_VDCDC1));

    mutex_unlock(&the_tps->lock);

    return status;
}
EXPORT_SYMBOL(tps65013_set_low_pwr);

/*-------------------------------------------------------------------------*/

static int __init tps_init(void)
{
    u32 tries = 3;
    int status = -ENODEV;

    printk(KERN_INFO "%s: version %s\n", DRIVER_NAME, DRIVER_VERSION);

    /* some boards have startup glitches */
    while (tries--) {
        status = i2c_add_driver(&tps65010_driver);
        if (the_tps)
            break;
        i2c_del_driver(&tps65010_driver);
        if (!tries) {
            printk(KERN_ERR "%s: no chip?\n", DRIVER_NAME);
            return -ENODEV;
        }
        pr_debug("%s: re-probe ...\n", DRIVER_NAME);
        msleep(10);
    }

    return status;
}
/* NOTE:  this MUST be initialized before the other parts of the system
 * that rely on it ... but after the i2c bus on which this relies.
 * That is, much earlier than on PC-type systems, which don't often use
 * I2C as a core system bus.
 */
subsys_initcall(tps_init);

static void __exit tps_exit(void)
{
    i2c_del_driver(&tps65010_driver);
}
module_exit(tps_exit);