2 * I2C client/driver for the ST M41T80 family of i2c rtc chips.
4 * Author: Alexander Bigga <ab@mycable.de>
6 * Based on m41t00.c by Mark A. Greer <mgreer@mvista.com>
8 * 2006 (c) mycable GmbH
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/bcd.h>
19 #include <linux/i2c.h>
20 #include <linux/init.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/rtc.h>
24 #include <linux/slab.h>
25 #include <linux/mutex.h>
26 #include <linux/string.h>
27 #ifdef CONFIG_RTC_DRV_M41T80_WDT
29 #include <linux/ioctl.h>
30 #include <linux/miscdevice.h>
31 #include <linux/reboot.h>
32 #include <linux/watchdog.h>
35 #define M41T80_REG_SSEC 0x00
36 #define M41T80_REG_SEC 0x01
37 #define M41T80_REG_MIN 0x02
38 #define M41T80_REG_HOUR 0x03
39 #define M41T80_REG_WDAY 0x04
40 #define M41T80_REG_DAY 0x05
41 #define M41T80_REG_MON 0x06
42 #define M41T80_REG_YEAR 0x07
43 #define M41T80_REG_ALARM_MON 0x0a
44 #define M41T80_REG_ALARM_DAY 0x0b
45 #define M41T80_REG_ALARM_HOUR 0x0c
46 #define M41T80_REG_ALARM_MIN 0x0d
47 #define M41T80_REG_ALARM_SEC 0x0e
48 #define M41T80_REG_FLAGS 0x0f
49 #define M41T80_REG_SQW 0x13
51 #define M41T80_DATETIME_REG_SIZE (M41T80_REG_YEAR + 1)
52 #define M41T80_ALARM_REG_SIZE \
53 (M41T80_REG_ALARM_SEC + 1 - M41T80_REG_ALARM_MON)
55 #define M41T80_SEC_ST BIT(7) /* ST: Stop Bit */
56 #define M41T80_ALMON_AFE BIT(7) /* AFE: AF Enable Bit */
57 #define M41T80_ALMON_SQWE BIT(6) /* SQWE: SQW Enable Bit */
58 #define M41T80_ALHOUR_HT BIT(6) /* HT: Halt Update Bit */
59 #define M41T80_FLAGS_AF BIT(6) /* AF: Alarm Flag Bit */
60 #define M41T80_FLAGS_BATT_LOW BIT(4) /* BL: Battery Low Bit */
61 #define M41T80_WATCHDOG_RB2 BIT(7) /* RB: Watchdog resolution */
62 #define M41T80_WATCHDOG_RB1 BIT(1) /* RB: Watchdog resolution */
63 #define M41T80_WATCHDOG_RB0 BIT(0) /* RB: Watchdog resolution */
65 #define M41T80_FEATURE_HT BIT(0) /* Halt feature */
66 #define M41T80_FEATURE_BL BIT(1) /* Battery low indicator */
67 #define M41T80_FEATURE_SQ BIT(2) /* Squarewave feature */
68 #define M41T80_FEATURE_WD BIT(3) /* Extra watchdog resolution */
69 #define M41T80_FEATURE_SQ_ALT BIT(4) /* RSx bits are in reg 4 */
71 static DEFINE_MUTEX(m41t80_rtc_mutex);
72 static const struct i2c_device_id m41t80_id[] = {
73 { "m41t62", M41T80_FEATURE_SQ | M41T80_FEATURE_SQ_ALT },
74 { "m41t65", M41T80_FEATURE_HT | M41T80_FEATURE_WD },
75 { "m41t80", M41T80_FEATURE_SQ },
76 { "m41t81", M41T80_FEATURE_HT | M41T80_FEATURE_SQ},
77 { "m41t81s", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
78 { "m41t82", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
79 { "m41t83", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
80 { "m41st84", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
81 { "m41st85", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
82 { "m41st87", M41T80_FEATURE_HT | M41T80_FEATURE_BL | M41T80_FEATURE_SQ },
83 { "rv4162", M41T80_FEATURE_SQ | M41T80_FEATURE_WD | M41T80_FEATURE_SQ_ALT },
86 MODULE_DEVICE_TABLE(i2c, m41t80_id);
90 struct rtc_device *rtc;
93 static irqreturn_t m41t80_handle_irq(int irq, void *dev_id)
95 struct i2c_client *client = dev_id;
96 struct m41t80_data *m41t80 = i2c_get_clientdata(client);
97 struct mutex *lock = &m41t80->rtc->ops_lock;
98 unsigned long events = 0;
103 flags_afe = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON);
109 flags = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS);
115 if (flags & M41T80_FLAGS_AF) {
116 flags &= ~M41T80_FLAGS_AF;
117 flags_afe &= ~M41T80_ALMON_AFE;
122 rtc_update_irq(m41t80->rtc, 1, events);
123 i2c_smbus_write_byte_data(client, M41T80_REG_FLAGS, flags);
124 i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON,
133 static int m41t80_get_datetime(struct i2c_client *client,
136 unsigned char buf[8];
139 err = i2c_smbus_read_i2c_block_data(client, M41T80_REG_SSEC,
142 dev_err(&client->dev, "Unable to read date\n");
146 tm->tm_sec = bcd2bin(buf[M41T80_REG_SEC] & 0x7f);
147 tm->tm_min = bcd2bin(buf[M41T80_REG_MIN] & 0x7f);
148 tm->tm_hour = bcd2bin(buf[M41T80_REG_HOUR] & 0x3f);
149 tm->tm_mday = bcd2bin(buf[M41T80_REG_DAY] & 0x3f);
150 tm->tm_wday = buf[M41T80_REG_WDAY] & 0x07;
151 tm->tm_mon = bcd2bin(buf[M41T80_REG_MON] & 0x1f) - 1;
153 /* assume 20YY not 19YY, and ignore the Century Bit */
154 tm->tm_year = bcd2bin(buf[M41T80_REG_YEAR]) + 100;
155 return rtc_valid_tm(tm);
158 /* Sets the given date and time to the real time clock. */
159 static int m41t80_set_datetime(struct i2c_client *client, struct rtc_time *tm)
161 unsigned char buf[8];
164 if (tm->tm_year < 100 || tm->tm_year > 199)
167 buf[M41T80_REG_SSEC] = 0;
168 buf[M41T80_REG_SEC] = bin2bcd(tm->tm_sec);
169 buf[M41T80_REG_MIN] = bin2bcd(tm->tm_min);
170 buf[M41T80_REG_HOUR] = bin2bcd(tm->tm_hour);
171 buf[M41T80_REG_DAY] = bin2bcd(tm->tm_mday);
172 buf[M41T80_REG_MON] = bin2bcd(tm->tm_mon + 1);
173 buf[M41T80_REG_YEAR] = bin2bcd(tm->tm_year - 100);
174 buf[M41T80_REG_WDAY] = tm->tm_wday;
176 err = i2c_smbus_write_i2c_block_data(client, M41T80_REG_SSEC,
179 dev_err(&client->dev, "Unable to write to date registers\n");
186 static int m41t80_rtc_proc(struct device *dev, struct seq_file *seq)
188 struct i2c_client *client = to_i2c_client(dev);
189 struct m41t80_data *clientdata = i2c_get_clientdata(client);
192 if (clientdata->features & M41T80_FEATURE_BL) {
193 reg = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS);
194 seq_printf(seq, "battery\t\t: %s\n",
195 (reg & M41T80_FLAGS_BATT_LOW) ? "exhausted" : "ok");
200 static int m41t80_rtc_read_time(struct device *dev, struct rtc_time *tm)
202 return m41t80_get_datetime(to_i2c_client(dev), tm);
205 static int m41t80_rtc_set_time(struct device *dev, struct rtc_time *tm)
207 return m41t80_set_datetime(to_i2c_client(dev), tm);
210 static int m41t80_alarm_irq_enable(struct device *dev, unsigned int enabled)
212 struct i2c_client *client = to_i2c_client(dev);
215 flags = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON);
220 flags |= M41T80_ALMON_AFE;
222 flags &= ~M41T80_ALMON_AFE;
224 retval = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON, flags);
226 dev_info(dev, "Unable to enable alarm IRQ %d\n", retval);
232 static int m41t80_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
234 struct i2c_client *client = to_i2c_client(dev);
238 alarmvals[0] = bin2bcd(alrm->time.tm_mon + 1);
239 alarmvals[1] = bin2bcd(alrm->time.tm_mday);
240 alarmvals[2] = bin2bcd(alrm->time.tm_hour);
241 alarmvals[3] = bin2bcd(alrm->time.tm_min);
242 alarmvals[4] = bin2bcd(alrm->time.tm_sec);
244 /* Clear AF and AFE flags */
245 ret = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON);
248 err = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON,
249 ret & ~(M41T80_ALMON_AFE));
251 dev_err(dev, "Unable to clear AFE bit\n");
255 ret = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS);
259 err = i2c_smbus_write_byte_data(client, M41T80_REG_FLAGS,
260 ret & ~(M41T80_FLAGS_AF));
262 dev_err(dev, "Unable to clear AF bit\n");
266 /* Write the alarm */
267 err = i2c_smbus_write_i2c_block_data(client, M41T80_REG_ALARM_MON,
272 /* Enable the alarm interrupt */
274 alarmvals[0] |= M41T80_ALMON_AFE;
275 err = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON,
284 static int m41t80_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
286 struct i2c_client *client = to_i2c_client(dev);
290 ret = i2c_smbus_read_i2c_block_data(client, M41T80_REG_ALARM_MON,
293 return ret < 0 ? ret : -EIO;
295 flags = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS);
299 alrm->time.tm_sec = bcd2bin(alarmvals[4] & 0x7f);
300 alrm->time.tm_min = bcd2bin(alarmvals[3] & 0x7f);
301 alrm->time.tm_hour = bcd2bin(alarmvals[2] & 0x3f);
302 alrm->time.tm_wday = -1;
303 alrm->time.tm_mday = bcd2bin(alarmvals[1] & 0x3f);
304 alrm->time.tm_mon = bcd2bin(alarmvals[0] & 0x3f);
305 alrm->time.tm_year = -1;
307 alrm->enabled = !!(alarmvals[0] & M41T80_ALMON_AFE);
308 alrm->pending = (flags & M41T80_FLAGS_AF) && alrm->enabled;
313 static struct rtc_class_ops m41t80_rtc_ops = {
314 .read_time = m41t80_rtc_read_time,
315 .set_time = m41t80_rtc_set_time,
316 .proc = m41t80_rtc_proc,
319 static ssize_t flags_show(struct device *dev,
320 struct device_attribute *attr, char *buf)
322 struct i2c_client *client = to_i2c_client(dev);
325 val = i2c_smbus_read_byte_data(client, M41T80_REG_FLAGS);
328 return sprintf(buf, "%#x\n", val);
330 static DEVICE_ATTR_RO(flags);
332 static ssize_t sqwfreq_show(struct device *dev,
333 struct device_attribute *attr, char *buf)
335 struct i2c_client *client = to_i2c_client(dev);
336 struct m41t80_data *clientdata = i2c_get_clientdata(client);
339 if (!(clientdata->features & M41T80_FEATURE_SQ))
342 reg_sqw = M41T80_REG_SQW;
343 if (clientdata->features & M41T80_FEATURE_SQ_ALT)
344 reg_sqw = M41T80_REG_WDAY;
345 val = i2c_smbus_read_byte_data(client, reg_sqw);
348 val = (val >> 4) & 0xf;
358 return sprintf(buf, "%d\n", val);
361 static ssize_t sqwfreq_store(struct device *dev,
362 struct device_attribute *attr,
363 const char *buf, size_t count)
365 struct i2c_client *client = to_i2c_client(dev);
366 struct m41t80_data *clientdata = i2c_get_clientdata(client);
367 int almon, sqw, reg_sqw, rc;
370 rc = kstrtoul(buf, 0, &val);
374 if (!(clientdata->features & M41T80_FEATURE_SQ))
378 if (!is_power_of_2(val))
388 /* disable SQW, set SQW frequency & re-enable */
389 almon = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_MON);
392 reg_sqw = M41T80_REG_SQW;
393 if (clientdata->features & M41T80_FEATURE_SQ_ALT)
394 reg_sqw = M41T80_REG_WDAY;
395 sqw = i2c_smbus_read_byte_data(client, reg_sqw);
398 sqw = (sqw & 0x0f) | (val << 4);
400 rc = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON,
401 almon & ~M41T80_ALMON_SQWE);
406 rc = i2c_smbus_write_byte_data(client, reg_sqw, sqw);
410 rc = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_MON,
411 almon | M41T80_ALMON_SQWE);
417 static DEVICE_ATTR_RW(sqwfreq);
419 static struct attribute *attrs[] = {
420 &dev_attr_flags.attr,
421 &dev_attr_sqwfreq.attr,
425 static struct attribute_group attr_group = {
429 #ifdef CONFIG_RTC_DRV_M41T80_WDT
431 *****************************************************************************
435 *****************************************************************************
437 static struct i2c_client *save_client;
440 #define WD_TIMO 60 /* 1..31 seconds */
442 static int wdt_margin = WD_TIMO;
443 module_param(wdt_margin, int, 0);
444 MODULE_PARM_DESC(wdt_margin, "Watchdog timeout in seconds (default 60s)");
446 static unsigned long wdt_is_open;
447 static int boot_flag;
452 * Reload counter one with the watchdog timeout. We don't bother reloading
453 * the cascade counter.
455 static void wdt_ping(void)
457 unsigned char i2c_data[2];
458 struct i2c_msg msgs1[1] = {
460 .addr = save_client->addr,
466 struct m41t80_data *clientdata = i2c_get_clientdata(save_client);
468 i2c_data[0] = 0x09; /* watchdog register */
471 i2c_data[1] = (wdt_margin & 0xFC) | 0x83; /* resolution = 4s */
474 * WDS = 1 (0x80), mulitplier = WD_TIMO, resolution = 1s (0x02)
476 i2c_data[1] = wdt_margin << 2 | 0x82;
479 * M41T65 has three bits for watchdog resolution. Don't set bit 7, as
480 * that would be an invalid resolution.
482 if (clientdata->features & M41T80_FEATURE_WD)
483 i2c_data[1] &= ~M41T80_WATCHDOG_RB2;
485 i2c_transfer(save_client->adapter, msgs1, 1);
493 static void wdt_disable(void)
495 unsigned char i2c_data[2], i2c_buf[0x10];
496 struct i2c_msg msgs0[2] = {
498 .addr = save_client->addr,
504 .addr = save_client->addr,
510 struct i2c_msg msgs1[1] = {
512 .addr = save_client->addr,
520 i2c_transfer(save_client->adapter, msgs0, 2);
524 i2c_transfer(save_client->adapter, msgs1, 1);
529 * @file: file handle to the watchdog
530 * @buf: buffer to write (unused as data does not matter here
531 * @count: count of bytes
532 * @ppos: pointer to the position to write. No seeks allowed
534 * A write to a watchdog device is defined as a keepalive signal. Any
535 * write of data will do, as we we don't define content meaning.
537 static ssize_t wdt_write(struct file *file, const char __user *buf,
538 size_t count, loff_t *ppos)
547 static ssize_t wdt_read(struct file *file, char __user *buf,
548 size_t count, loff_t *ppos)
555 * @inode: inode of the device
556 * @file: file handle to the device
557 * @cmd: watchdog command
558 * @arg: argument pointer
560 * The watchdog API defines a common set of functions for all watchdogs
561 * according to their available features. We only actually usefully support
562 * querying capabilities and current status.
564 static int wdt_ioctl(struct file *file, unsigned int cmd,
568 static struct watchdog_info ident = {
569 .options = WDIOF_POWERUNDER | WDIOF_KEEPALIVEPING |
571 .firmware_version = 1,
572 .identity = "M41T80 WTD"
576 case WDIOC_GETSUPPORT:
577 return copy_to_user((struct watchdog_info __user *)arg, &ident,
578 sizeof(ident)) ? -EFAULT : 0;
580 case WDIOC_GETSTATUS:
581 case WDIOC_GETBOOTSTATUS:
582 return put_user(boot_flag, (int __user *)arg);
583 case WDIOC_KEEPALIVE:
586 case WDIOC_SETTIMEOUT:
587 if (get_user(new_margin, (int __user *)arg))
589 /* Arbitrary, can't find the card's limits */
590 if (new_margin < 1 || new_margin > 124)
592 wdt_margin = new_margin;
595 case WDIOC_GETTIMEOUT:
596 return put_user(wdt_margin, (int __user *)arg);
598 case WDIOC_SETOPTIONS:
599 if (copy_from_user(&rv, (int __user *)arg, sizeof(int)))
602 if (rv & WDIOS_DISABLECARD) {
603 pr_info("disable watchdog\n");
607 if (rv & WDIOS_ENABLECARD) {
608 pr_info("enable watchdog\n");
617 static long wdt_unlocked_ioctl(struct file *file, unsigned int cmd,
622 mutex_lock(&m41t80_rtc_mutex);
623 ret = wdt_ioctl(file, cmd, arg);
624 mutex_unlock(&m41t80_rtc_mutex);
631 * @inode: inode of device
632 * @file: file handle to device
635 static int wdt_open(struct inode *inode, struct file *file)
637 if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) {
638 mutex_lock(&m41t80_rtc_mutex);
639 if (test_and_set_bit(0, &wdt_is_open)) {
640 mutex_unlock(&m41t80_rtc_mutex);
647 mutex_unlock(&m41t80_rtc_mutex);
648 return nonseekable_open(inode, file);
655 * @inode: inode to board
656 * @file: file handle to board
659 static int wdt_release(struct inode *inode, struct file *file)
661 if (MINOR(inode->i_rdev) == WATCHDOG_MINOR)
662 clear_bit(0, &wdt_is_open);
668 * @this: our notifier block
669 * @code: the event being reported
672 * Our notifier is called on system shutdowns. We want to turn the card
673 * off at reboot otherwise the machine will reboot again during memory
674 * test or worse yet during the following fsck. This would suck, in fact
675 * trust me - if it happens it does suck.
677 static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
680 if (code == SYS_DOWN || code == SYS_HALT)
681 /* Disable Watchdog */
686 static const struct file_operations wdt_fops = {
687 .owner = THIS_MODULE,
689 .unlocked_ioctl = wdt_unlocked_ioctl,
692 .release = wdt_release,
696 static struct miscdevice wdt_dev = {
697 .minor = WATCHDOG_MINOR,
703 * The WDT card needs to learn about soft shutdowns in order to
704 * turn the timebomb registers off.
706 static struct notifier_block wdt_notifier = {
707 .notifier_call = wdt_notify_sys,
709 #endif /* CONFIG_RTC_DRV_M41T80_WDT */
712 *****************************************************************************
716 *****************************************************************************
719 static void m41t80_remove_sysfs_group(void *_dev)
721 struct device *dev = _dev;
723 sysfs_remove_group(&dev->kobj, &attr_group);
726 static int m41t80_probe(struct i2c_client *client,
727 const struct i2c_device_id *id)
729 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
731 struct rtc_device *rtc = NULL;
733 struct m41t80_data *m41t80_data = NULL;
735 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
736 I2C_FUNC_SMBUS_BYTE_DATA)) {
737 dev_err(&adapter->dev, "doesn't support I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK\n");
741 m41t80_data = devm_kzalloc(&client->dev, sizeof(*m41t80_data),
746 m41t80_data->features = id->driver_data;
747 i2c_set_clientdata(client, m41t80_data);
749 if (client->irq > 0) {
750 rc = devm_request_threaded_irq(&client->dev, client->irq,
751 NULL, m41t80_handle_irq,
752 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
755 dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
758 m41t80_rtc_ops.read_alarm = m41t80_read_alarm;
759 m41t80_rtc_ops.set_alarm = m41t80_set_alarm;
760 m41t80_rtc_ops.alarm_irq_enable = m41t80_alarm_irq_enable;
764 rtc = devm_rtc_device_register(&client->dev, client->name,
765 &m41t80_rtc_ops, THIS_MODULE);
769 m41t80_data->rtc = rtc;
771 /* Make sure HT (Halt Update) bit is cleared */
772 rc = i2c_smbus_read_byte_data(client, M41T80_REG_ALARM_HOUR);
774 if (rc >= 0 && rc & M41T80_ALHOUR_HT) {
775 if (m41t80_data->features & M41T80_FEATURE_HT) {
776 m41t80_get_datetime(client, &tm);
777 dev_info(&client->dev, "HT bit was set!\n");
778 dev_info(&client->dev,
779 "Power Down at %04i-%02i-%02i %02i:%02i:%02i\n",
781 tm.tm_mon + 1, tm.tm_mday, tm.tm_hour,
782 tm.tm_min, tm.tm_sec);
784 rc = i2c_smbus_write_byte_data(client, M41T80_REG_ALARM_HOUR,
785 rc & ~M41T80_ALHOUR_HT);
789 dev_err(&client->dev, "Can't clear HT bit\n");
793 /* Make sure ST (stop) bit is cleared */
794 rc = i2c_smbus_read_byte_data(client, M41T80_REG_SEC);
796 if (rc >= 0 && rc & M41T80_SEC_ST)
797 rc = i2c_smbus_write_byte_data(client, M41T80_REG_SEC,
798 rc & ~M41T80_SEC_ST);
800 dev_err(&client->dev, "Can't clear ST bit\n");
804 /* Export sysfs entries */
805 rc = sysfs_create_group(&(&client->dev)->kobj, &attr_group);
807 dev_err(&client->dev, "Failed to create sysfs group: %d\n", rc);
811 rc = devm_add_action(&client->dev, m41t80_remove_sysfs_group,
814 m41t80_remove_sysfs_group(&client->dev);
815 dev_err(&client->dev,
816 "Failed to add sysfs cleanup action: %d\n", rc);
820 #ifdef CONFIG_RTC_DRV_M41T80_WDT
821 if (m41t80_data->features & M41T80_FEATURE_HT) {
822 save_client = client;
823 rc = misc_register(&wdt_dev);
826 rc = register_reboot_notifier(&wdt_notifier);
828 misc_deregister(&wdt_dev);
836 static int m41t80_remove(struct i2c_client *client)
838 #ifdef CONFIG_RTC_DRV_M41T80_WDT
839 struct m41t80_data *clientdata = i2c_get_clientdata(client);
841 if (clientdata->features & M41T80_FEATURE_HT) {
842 misc_deregister(&wdt_dev);
843 unregister_reboot_notifier(&wdt_notifier);
850 static struct i2c_driver m41t80_driver = {
852 .name = "rtc-m41t80",
854 .probe = m41t80_probe,
855 .remove = m41t80_remove,
856 .id_table = m41t80_id,
859 module_i2c_driver(m41t80_driver);
861 MODULE_AUTHOR("Alexander Bigga <ab@mycable.de>");
862 MODULE_DESCRIPTION("ST Microelectronics M41T80 series RTC I2C Client Driver");
863 MODULE_LICENSE("GPL");