rtc-isl1208.c

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/*
 * Intersil ISL1208 rtc class driver
 *
 * Copyright 2005,2006 Hebert Valerio Riedel <[email protected]>
 *
 *  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/module.h>
#include <linux/i2c.h>
#include <linux/bcd.h>
#include <linux/rtc.h>

#define DRV_VERSION "0.3"

/* Register map */
/* rtc section */
#define ISL1208_REG_SC  0x00
#define ISL1208_REG_MN  0x01
#define ISL1208_REG_HR  0x02
#define ISL1208_REG_HR_MIL     (1<<7)   /* 24h/12h mode */
#define ISL1208_REG_HR_PM      (1<<5)   /* PM/AM bit in 12h mode */
#define ISL1208_REG_DT  0x03
#define ISL1208_REG_MO  0x04
#define ISL1208_REG_YR  0x05
#define ISL1208_REG_DW  0x06
#define ISL1208_RTC_SECTION_LEN 7

/* control/status section */
#define ISL1208_REG_SR  0x07
#define ISL1208_REG_SR_ARST    (1<<7)   /* auto reset */
#define ISL1208_REG_SR_XTOSCB  (1<<6)   /* crystal oscillator */
#define ISL1208_REG_SR_WRTC    (1<<4)   /* write rtc */
#define ISL1208_REG_SR_ALM     (1<<2)   /* alarm */
#define ISL1208_REG_SR_BAT     (1<<1)   /* battery */
#define ISL1208_REG_SR_RTCF    (1<<0)   /* rtc fail */
#define ISL1208_REG_INT 0x08
#define ISL1208_REG_INT_ALME   (1<<6)   /* alarm enable */
#define ISL1208_REG_INT_IM     (1<<7)   /* interrupt/alarm mode */
#define ISL1208_REG_09  0x09    /* reserved */
#define ISL1208_REG_ATR 0x0a
#define ISL1208_REG_DTR 0x0b

/* alarm section */
#define ISL1208_REG_SCA 0x0c
#define ISL1208_REG_MNA 0x0d
#define ISL1208_REG_HRA 0x0e
#define ISL1208_REG_DTA 0x0f
#define ISL1208_REG_MOA 0x10
#define ISL1208_REG_DWA 0x11
#define ISL1208_ALARM_SECTION_LEN 6

/* user section */
#define ISL1208_REG_USR1 0x12
#define ISL1208_REG_USR2 0x13
#define ISL1208_USR_SECTION_LEN 2

static struct i2c_driver isl1208_driver;

/* block read */
static int
isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[],
              unsigned len)
{
    u8 reg_addr[1] = { reg };
    struct i2c_msg msgs[2] = {
        {
            .addr = client->addr,
            .len = sizeof(reg_addr),
            .buf = reg_addr
        },
        {
            .addr = client->addr,
            .flags = I2C_M_RD,
            .len = len,
            .buf = buf
        }
    };
    int ret;

    BUG_ON(reg > ISL1208_REG_USR2);
    BUG_ON(reg + len > ISL1208_REG_USR2 + 1);

    ret = i2c_transfer(client->adapter, msgs, 2);
    if (ret > 0)
        ret = 0;
    return ret;
}

/* block write */
static int
isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[],
             unsigned len)
{
    u8 i2c_buf[ISL1208_REG_USR2 + 2];
    struct i2c_msg msgs[1] = {
        {
            .addr = client->addr,
            .len = len + 1,
            .buf = i2c_buf
        }
    };
    int ret;

    BUG_ON(reg > ISL1208_REG_USR2);
    BUG_ON(reg + len > ISL1208_REG_USR2 + 1);

    i2c_buf[0] = reg;
    memcpy(&i2c_buf[1], &buf[0], len);

    ret = i2c_transfer(client->adapter, msgs, 1);
    if (ret > 0)
        ret = 0;
    return ret;
}

/* simple check to see wether we have a isl1208 */
static int
isl1208_i2c_validate_client(struct i2c_client *client)
{
    u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
    u8 zero_mask[ISL1208_RTC_SECTION_LEN] = {
        0x80, 0x80, 0x40, 0xc0, 0xe0, 0x00, 0xf8
    };
    int i;
    int ret;

    ret = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
    if (ret < 0)
        return ret;

    for (i = 0; i < ISL1208_RTC_SECTION_LEN; ++i) {
        if (regs[i] & zero_mask[i]) /* check if bits are cleared */
            return -ENODEV;
    }

    return 0;
}

static int
isl1208_i2c_get_sr(struct i2c_client *client)
{
    int sr = i2c_smbus_read_byte_data(client, ISL1208_REG_SR);
    if (sr < 0)
        return -EIO;

    return sr;
}

static int
isl1208_i2c_get_atr(struct i2c_client *client)
{
    int atr = i2c_smbus_read_byte_data(client, ISL1208_REG_ATR);
    if (atr < 0)
        return atr;

    /* The 6bit value in the ATR register controls the load
     * capacitance C_load * in steps of 0.25pF
     *
     * bit (1<<5) of the ATR register is inverted
     *
     * C_load(ATR=0x20) =  4.50pF
     * C_load(ATR=0x00) = 12.50pF
     * C_load(ATR=0x1f) = 20.25pF
     *
     */

    atr &= 0x3f;        /* mask out lsb */
    atr ^= 1 << 5;      /* invert 6th bit */
    atr += 2 * 9;       /* add offset of 4.5pF; unit[atr] = 0.25pF */

    return atr;
}

static int
isl1208_i2c_get_dtr(struct i2c_client *client)
{
    int dtr = i2c_smbus_read_byte_data(client, ISL1208_REG_DTR);
    if (dtr < 0)
        return -EIO;

    /* dtr encodes adjustments of {-60,-40,-20,0,20,40,60} ppm */
    dtr = ((dtr & 0x3) * 20) * (dtr & (1 << 2) ? -1 : 1);

    return dtr;
}

static int
isl1208_i2c_get_usr(struct i2c_client *client)
{
    u8 buf[ISL1208_USR_SECTION_LEN] = { 0, };
    int ret;

    ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1, buf,
                    ISL1208_USR_SECTION_LEN);
    if (ret < 0)
        return ret;

    return (buf[1] << 8) | buf[0];
}

static int
isl1208_i2c_set_usr(struct i2c_client *client, u16 usr)
{
    u8 buf[ISL1208_USR_SECTION_LEN];

    buf[0] = usr & 0xff;
    buf[1] = (usr >> 8) & 0xff;

    return isl1208_i2c_set_regs(client, ISL1208_REG_USR1, buf,
                    ISL1208_USR_SECTION_LEN);
}

static int
isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable)
{
    int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);

    if (icr < 0) {
        dev_err(&client->dev, "%s: reading INT failed\n", __func__);
        return icr;
    }

    if (enable)
        icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM;
    else
        icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM);

    icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr);
    if (icr < 0) {
        dev_err(&client->dev, "%s: writing INT failed\n", __func__);
        return icr;
    }

    return 0;
}

static int
isl1208_rtc_proc(struct device *dev, struct seq_file *seq)
{
    struct i2c_client *const client = to_i2c_client(dev);
    int sr, dtr, atr, usr;

    sr = isl1208_i2c_get_sr(client);
    if (sr < 0) {
        dev_err(&client->dev, "%s: reading SR failed\n", __func__);
        return sr;
    }

    seq_printf(seq, "status_reg\t:%s%s%s%s%s%s (0x%.2x)\n",
           (sr & ISL1208_REG_SR_RTCF) ? " RTCF" : "",
           (sr & ISL1208_REG_SR_BAT) ? " BAT" : "",
           (sr & ISL1208_REG_SR_ALM) ? " ALM" : "",
           (sr & ISL1208_REG_SR_WRTC) ? " WRTC" : "",
           (sr & ISL1208_REG_SR_XTOSCB) ? " XTOSCB" : "",
           (sr & ISL1208_REG_SR_ARST) ? " ARST" : "", sr);

    seq_printf(seq, "batt_status\t: %s\n",
           (sr & ISL1208_REG_SR_RTCF) ? "bad" : "okay");

    dtr = isl1208_i2c_get_dtr(client);
    if (dtr >= 0 - 1)
        seq_printf(seq, "digital_trim\t: %d ppm\n", dtr);

    atr = isl1208_i2c_get_atr(client);
    if (atr >= 0)
        seq_printf(seq, "analog_trim\t: %d.%.2d pF\n",
               atr >> 2, (atr & 0x3) * 25);

    usr = isl1208_i2c_get_usr(client);
    if (usr >= 0)
        seq_printf(seq, "user_data\t: 0x%.4x\n", usr);

    return 0;
}

static int
isl1208_i2c_read_time(struct i2c_client *client, struct rtc_time *tm)
{
    int sr;
    u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };

    sr = isl1208_i2c_get_sr(client);
    if (sr < 0) {
        dev_err(&client->dev, "%s: reading SR failed\n", __func__);
        return -EIO;
    }

    sr = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
    if (sr < 0) {
        dev_err(&client->dev, "%s: reading RTC section failed\n",
            __func__);
        return sr;
    }

    tm->tm_sec = bcd2bin(regs[ISL1208_REG_SC]);
    tm->tm_min = bcd2bin(regs[ISL1208_REG_MN]);

    /* HR field has a more complex interpretation */
    {
        const u8 _hr = regs[ISL1208_REG_HR];
        if (_hr & ISL1208_REG_HR_MIL)   /* 24h format */
            tm->tm_hour = bcd2bin(_hr & 0x3f);
        else {
            /* 12h format */
            tm->tm_hour = bcd2bin(_hr & 0x1f);
            if (_hr & ISL1208_REG_HR_PM)    /* PM flag set */
                tm->tm_hour += 12;
        }
    }

    tm->tm_mday = bcd2bin(regs[ISL1208_REG_DT]);
    tm->tm_mon = bcd2bin(regs[ISL1208_REG_MO]) - 1; /* rtc starts at 1 */
    tm->tm_year = bcd2bin(regs[ISL1208_REG_YR]) + 100;
    tm->tm_wday = bcd2bin(regs[ISL1208_REG_DW]);

    return 0;
}

static int
isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm)
{
    struct rtc_time *const tm = &alarm->time;
    u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };
    int icr, yr, sr = isl1208_i2c_get_sr(client);

    if (sr < 0) {
        dev_err(&client->dev, "%s: reading SR failed\n", __func__);
        return sr;
    }

    sr = isl1208_i2c_read_regs(client, ISL1208_REG_SCA, regs,
                   ISL1208_ALARM_SECTION_LEN);
    if (sr < 0) {
        dev_err(&client->dev, "%s: reading alarm section failed\n",
            __func__);
        return sr;
    }

    /* MSB of each alarm register is an enable bit */
    tm->tm_sec = bcd2bin(regs[ISL1208_REG_SCA - ISL1208_REG_SCA] & 0x7f);
    tm->tm_min = bcd2bin(regs[ISL1208_REG_MNA - ISL1208_REG_SCA] & 0x7f);
    tm->tm_hour = bcd2bin(regs[ISL1208_REG_HRA - ISL1208_REG_SCA] & 0x3f);
    tm->tm_mday = bcd2bin(regs[ISL1208_REG_DTA - ISL1208_REG_SCA] & 0x3f);
    tm->tm_mon =
        bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1;
    tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03);

    /* The alarm doesn't store the year so get it from the rtc section */
    yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR);
    if (yr < 0) {
        dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__);
        return yr;
    }
    tm->tm_year = bcd2bin(yr) + 100;

    icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);
    if (icr < 0) {
        dev_err(&client->dev, "%s: reading INT failed\n", __func__);
        return icr;
    }
    alarm->enabled = !!(icr & ISL1208_REG_INT_ALME);

    return 0;
}

static int
isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm)
{
    struct rtc_time *alarm_tm = &alarm->time;
    u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };
    const int offs = ISL1208_REG_SCA;
    unsigned long rtc_secs, alarm_secs;
    struct rtc_time rtc_tm;
    int err, enable;

    err = isl1208_i2c_read_time(client, &rtc_tm);
    if (err)
        return err;
    err = rtc_tm_to_time(&rtc_tm, &rtc_secs);
    if (err)
        return err;
    err = rtc_tm_to_time(alarm_tm, &alarm_secs);
    if (err)
        return err;

    /* If the alarm time is before the current time disable the alarm */
    if (!alarm->enabled || alarm_secs <= rtc_secs)
        enable = 0x00;
    else
        enable = 0x80;

    /* Program the alarm and enable it for each setting */
    regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable;
    regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable;
    regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) |
        ISL1208_REG_HR_MIL | enable;

    regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable;
    regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable;
    regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable;

    /* write ALARM registers */
    err = isl1208_i2c_set_regs(client, offs, regs,
                  ISL1208_ALARM_SECTION_LEN);
    if (err < 0) {
        dev_err(&client->dev, "%s: writing ALARM section failed\n",
            __func__);
        return err;
    }

    err = isl1208_rtc_toggle_alarm(client, enable);
    if (err)
        return err;

    return 0;
}

static int
isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
    return isl1208_i2c_read_time(to_i2c_client(dev), tm);
}

static int
isl1208_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm)
{
    int sr;
    u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };

    /* The clock has an 8 bit wide bcd-coded register (they never learn)
     * for the year. tm_year is an offset from 1900 and we are interested
     * in the 2000-2099 range, so any value less than 100 is invalid.
     */
    if (tm->tm_year < 100)
        return -EINVAL;

    regs[ISL1208_REG_SC] = bin2bcd(tm->tm_sec);
    regs[ISL1208_REG_MN] = bin2bcd(tm->tm_min);
    regs[ISL1208_REG_HR] = bin2bcd(tm->tm_hour) | ISL1208_REG_HR_MIL;

    regs[ISL1208_REG_DT] = bin2bcd(tm->tm_mday);
    regs[ISL1208_REG_MO] = bin2bcd(tm->tm_mon + 1);
    regs[ISL1208_REG_YR] = bin2bcd(tm->tm_year - 100);

    regs[ISL1208_REG_DW] = bin2bcd(tm->tm_wday & 7);

    sr = isl1208_i2c_get_sr(client);
    if (sr < 0) {
        dev_err(&client->dev, "%s: reading SR failed\n", __func__);
        return sr;
    }

    /* set WRTC */
    sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
                       sr | ISL1208_REG_SR_WRTC);
    if (sr < 0) {
        dev_err(&client->dev, "%s: writing SR failed\n", __func__);
        return sr;
    }

    /* write RTC registers */
    sr = isl1208_i2c_set_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
    if (sr < 0) {
        dev_err(&client->dev, "%s: writing RTC section failed\n",
            __func__);
        return sr;
    }

    /* clear WRTC again */
    sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
                       sr & ~ISL1208_REG_SR_WRTC);
    if (sr < 0) {
        dev_err(&client->dev, "%s: writing SR failed\n", __func__);
        return sr;
    }

    return 0;
}


static int
isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
    return isl1208_i2c_set_time(to_i2c_client(dev), tm);
}

static int
isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
    return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm);
}

static int
isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
    return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm);
}

static irqreturn_t
isl1208_rtc_interrupt(int irq, void *data)
{
    unsigned long timeout = jiffies + msecs_to_jiffies(1000);
    struct i2c_client *client = data;
    int handled = 0, sr, err;

    /*
     * I2C reads get NAK'ed if we read straight away after an interrupt?
     * Using a mdelay/msleep didn't seem to help either, so we work around
     * this by continually trying to read the register for a short time.
     */
    while (1) {
        sr = isl1208_i2c_get_sr(client);
        if (sr >= 0)
            break;

        if (time_after(jiffies, timeout)) {
            dev_err(&client->dev, "%s: reading SR failed\n",
                __func__);
            return sr;
        }
    }

    if (sr & ISL1208_REG_SR_ALM) {
        dev_dbg(&client->dev, "alarm!\n");

        /* Clear the alarm */
        sr &= ~ISL1208_REG_SR_ALM;
        sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr);
        if (sr < 0)
            dev_err(&client->dev, "%s: writing SR failed\n",
                __func__);
        else
            handled = 1;

        /* Disable the alarm */
        err = isl1208_rtc_toggle_alarm(client, 0);
        if (err)
            return err;
    }

    return handled ? IRQ_HANDLED : IRQ_NONE;
}

static const struct rtc_class_ops isl1208_rtc_ops = {
    .proc = isl1208_rtc_proc,
    .read_time = isl1208_rtc_read_time,
    .set_time = isl1208_rtc_set_time,
    .read_alarm = isl1208_rtc_read_alarm,
    .set_alarm = isl1208_rtc_set_alarm,
};

/* sysfs interface */

static ssize_t
isl1208_sysfs_show_atrim(struct device *dev,
             struct device_attribute *attr, char *buf)
{
    int atr = isl1208_i2c_get_atr(to_i2c_client(dev));
    if (atr < 0)
        return atr;

    return sprintf(buf, "%d.%.2d pF\n", atr >> 2, (atr & 0x3) * 25);
}

static DEVICE_ATTR(atrim, S_IRUGO, isl1208_sysfs_show_atrim, NULL);

static ssize_t
isl1208_sysfs_show_dtrim(struct device *dev,
             struct device_attribute *attr, char *buf)
{
    int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev));
    if (dtr < 0)
        return dtr;

    return sprintf(buf, "%d ppm\n", dtr);
}

static DEVICE_ATTR(dtrim, S_IRUGO, isl1208_sysfs_show_dtrim, NULL);

static ssize_t
isl1208_sysfs_show_usr(struct device *dev,
               struct device_attribute *attr, char *buf)
{
    int usr = isl1208_i2c_get_usr(to_i2c_client(dev));
    if (usr < 0)
        return usr;

    return sprintf(buf, "0x%.4x\n", usr);
}

static ssize_t
isl1208_sysfs_store_usr(struct device *dev,
            struct device_attribute *attr,
            const char *buf, size_t count)
{
    int usr = -1;

    if (buf[0] == '0' && (buf[1] == 'x' || buf[1] == 'X')) {
        if (sscanf(buf, "%x", &usr) != 1)
            return -EINVAL;
    } else {
        if (sscanf(buf, "%d", &usr) != 1)
            return -EINVAL;
    }

    if (usr < 0 || usr > 0xffff)
        return -EINVAL;

    return isl1208_i2c_set_usr(to_i2c_client(dev), usr) ? -EIO : count;
}

static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr,
           isl1208_sysfs_store_usr);

static struct attribute *isl1208_rtc_attrs[] = {
    &dev_attr_atrim.attr,
    &dev_attr_dtrim.attr,
    &dev_attr_usr.attr,
    NULL
};

static const struct attribute_group isl1208_rtc_sysfs_files = {
    .attrs  = isl1208_rtc_attrs,
};

static int
isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
    int rc = 0;
    struct rtc_device *rtc;

    if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
        return -ENODEV;

    if (isl1208_i2c_validate_client(client) < 0)
        return -ENODEV;

    dev_info(&client->dev,
         "chip found, driver version " DRV_VERSION "\n");

    if (client->irq > 0) {
        rc = request_threaded_irq(client->irq, NULL,
                      isl1208_rtc_interrupt,
                      IRQF_SHARED,
                      isl1208_driver.driver.name, client);
        if (!rc) {
            device_init_wakeup(&client->dev, 1);
            enable_irq_wake(client->irq);
        } else {
            dev_err(&client->dev,
                "Unable to request irq %d, no alarm support\n",
                client->irq);
            client->irq = 0;
        }
    }

    rtc = rtc_device_register(isl1208_driver.driver.name,
                  &client->dev, &isl1208_rtc_ops,
                  THIS_MODULE);
    if (IS_ERR(rtc)) {
        rc = PTR_ERR(rtc);
        goto exit_free_irq;
    }

    i2c_set_clientdata(client, rtc);

    rc = isl1208_i2c_get_sr(client);
    if (rc < 0) {
        dev_err(&client->dev, "reading status failed\n");
        goto exit_unregister;
    }

    if (rc & ISL1208_REG_SR_RTCF)
        dev_warn(&client->dev, "rtc power failure detected, "
             "please set clock.\n");

    rc = sysfs_create_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
    if (rc)
        goto exit_unregister;

    return 0;

exit_unregister:
    rtc_device_unregister(rtc);
exit_free_irq:
    if (client->irq)
        free_irq(client->irq, client);

    return rc;
}

static int
isl1208_remove(struct i2c_client *client)
{
    struct rtc_device *rtc = i2c_get_clientdata(client);

    sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
    rtc_device_unregister(rtc);
    if (client->irq)
        free_irq(client->irq, client);

    return 0;
}

static const struct i2c_device_id isl1208_id[] = {
    { "isl1208", 0 },
    { "isl1218", 0 },
    { }
};
MODULE_DEVICE_TABLE(i2c, isl1208_id);

static struct i2c_driver isl1208_driver = {
    .driver = {
           .name = "rtc-isl1208",
           },
    .probe = isl1208_probe,
    .remove = isl1208_remove,
    .id_table = isl1208_id,
};

module_i2c_driver(isl1208_driver);

MODULE_AUTHOR("Herbert Valerio Riedel <[email protected]>");
MODULE_DESCRIPTION("Intersil ISL1208 RTC driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);