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-rw-r--r--kernel/drivers/rtc/rtc-isl1208.c716
1 files changed, 716 insertions, 0 deletions
diff --git a/kernel/drivers/rtc/rtc-isl1208.c b/kernel/drivers/rtc/rtc-isl1208.c
new file mode 100644
index 000000000..c3c549d51
--- /dev/null
+++ b/kernel/drivers/rtc/rtc-isl1208.c
@@ -0,0 +1,716 @@
+/*
+ * Intersil ISL1208 rtc class driver
+ *
+ * Copyright 2005,2006 Hebert Valerio Riedel <hvr@gnu.org>
+ *
+ * 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 whether 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)
+{
+ return i2c_smbus_read_byte_data(client, ISL1208_REG_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;
+ struct rtc_device *rtc = i2c_get_clientdata(client);
+ 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");
+
+ rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
+
+ /* 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 = devm_request_threaded_irq(&client->dev, 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 = devm_rtc_device_register(&client->dev, isl1208_driver.driver.name,
+ &isl1208_rtc_ops,
+ THIS_MODULE);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ i2c_set_clientdata(client, rtc);
+
+ rc = isl1208_i2c_get_sr(client);
+ if (rc < 0) {
+ dev_err(&client->dev, "reading status failed\n");
+ return rc;
+ }
+
+ 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)
+ return rc;
+
+ return 0;
+}
+
+static int
+isl1208_remove(struct i2c_client *client)
+{
+ sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
+
+ 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 <hvr@gnu.org>");
+MODULE_DESCRIPTION("Intersil ISL1208 RTC driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);