// SPDX-License-Identifier: GPL-2.0-or-later

  /*

   * RTC client/driver for the Maxim/Dallas DS3232/DS3234 Real-Time Clock

   *

   * Copyright (C) 2009-2011 Freescale Semiconductor.

   * Author: Jack Lan <jack.lan@freescale.com>

   * Copyright (C) 2008 MIMOMax Wireless Ltd.

   */

  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/interrupt.h>
  #include <linux/i2c.h>

  #include <linux/spi/spi.h>

  #include <linux/rtc.h>
  #include <linux/bcd.h>

  #include <linux/slab.h>

  #include <linux/regmap.h>

  #include <linux/hwmon.h>

  #define DS3232_REG_SECONDS      0x00
  #define DS3232_REG_MINUTES      0x01
  #define DS3232_REG_HOURS        0x02
  #define DS3232_REG_AMPM         0x02
  #define DS3232_REG_DAY          0x03
  #define DS3232_REG_DATE         0x04
  #define DS3232_REG_MONTH        0x05
  #define DS3232_REG_CENTURY      0x05
  #define DS3232_REG_YEAR         0x06
  #define DS3232_REG_ALARM1       0x07       /* Alarm 1 BASE */
  #define DS3232_REG_ALARM2       0x0B       /* Alarm 2 BASE */
  #define DS3232_REG_CR           0x0E       /* Control register */
  #       define DS3232_REG_CR_nEOSC   0x80
  #       define DS3232_REG_CR_INTCN   0x04
  #       define DS3232_REG_CR_A2IE    0x02
  #       define DS3232_REG_CR_A1IE    0x01

  #define DS3232_REG_SR           0x0F       /* control/status register */
  #       define DS3232_REG_SR_OSF     0x80
  #       define DS3232_REG_SR_BSY     0x04
  #       define DS3232_REG_SR_A2F     0x02
  #       define DS3232_REG_SR_A1F     0x01

  #define DS3232_REG_TEMPERATURE	0x11

  #define DS3232_REG_SRAM_START   0x14
  #define DS3232_REG_SRAM_END     0xFF
  
  #define DS3232_REG_SRAM_SIZE    236

  struct ds3232 {

  	struct device *dev;
  	struct regmap *regmap;
  	int irq;

  	struct rtc_device *rtc;

  	bool suspended;

  };

  static int ds3232_check_rtc_status(struct device *dev)

  {

  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	int ret = 0;
  	int control, stat;

  	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
  	if (ret)
  		return ret;

  
  	if (stat & DS3232_REG_SR_OSF)

  		dev_warn(dev,

  				"oscillator discontinuity flagged, "
  				"time unreliable
  ");
  
  	stat &= ~(DS3232_REG_SR_OSF | DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);

  	ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
  	if (ret)

  		return ret;
  
  	/* If the alarm is pending, clear it before requesting
  	 * the interrupt, so an interrupt event isn't reported
  	 * before everything is initialized.
  	 */

  	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
  	if (ret)
  		return ret;

  
  	control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
  	control |= DS3232_REG_CR_INTCN;

  	return regmap_write(ds3232->regmap, DS3232_REG_CR, control);

  }
  
  static int ds3232_read_time(struct device *dev, struct rtc_time *time)
  {

  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	int ret;
  	u8 buf[7];
  	unsigned int year, month, day, hour, minute, second;
  	unsigned int week, twelve_hr, am_pm;
  	unsigned int century, add_century = 0;

  	ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
  	if (ret)

  		return ret;

  
  	second = buf[0];
  	minute = buf[1];
  	hour = buf[2];
  	week = buf[3];
  	day = buf[4];
  	month = buf[5];
  	year = buf[6];
  
  	/* Extract additional information for AM/PM and century */
  
  	twelve_hr = hour & 0x40;
  	am_pm = hour & 0x20;
  	century = month & 0x80;
  
  	/* Write to rtc_time structure */
  
  	time->tm_sec = bcd2bin(second);
  	time->tm_min = bcd2bin(minute);
  	if (twelve_hr) {
  		/* Convert to 24 hr */
  		if (am_pm)
  			time->tm_hour = bcd2bin(hour & 0x1F) + 12;
  		else
  			time->tm_hour = bcd2bin(hour & 0x1F);
  	} else {
  		time->tm_hour = bcd2bin(hour);
  	}

  	/* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
  	time->tm_wday = bcd2bin(week) - 1;

  	time->tm_mday = bcd2bin(day);

  	/* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
  	time->tm_mon = bcd2bin(month & 0x7F) - 1;

  	if (century)
  		add_century = 100;
  
  	time->tm_year = bcd2bin(year) + add_century;

  	return 0;

  }
  
  static int ds3232_set_time(struct device *dev, struct rtc_time *time)
  {

  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	u8 buf[7];
  
  	/* Extract time from rtc_time and load into ds3232*/
  
  	buf[0] = bin2bcd(time->tm_sec);
  	buf[1] = bin2bcd(time->tm_min);
  	buf[2] = bin2bcd(time->tm_hour);

  	/* Day of the week in linux range is 0~6 while 1~7 in RTC chip */
  	buf[3] = bin2bcd(time->tm_wday + 1);

  	buf[4] = bin2bcd(time->tm_mday); /* Date */

  	/* linux tm_mon range:0~11, while month range is 1~12 in RTC chip */
  	buf[5] = bin2bcd(time->tm_mon + 1);

  	if (time->tm_year >= 100) {
  		buf[5] |= 0x80;
  		buf[6] = bin2bcd(time->tm_year - 100);
  	} else {
  		buf[6] = bin2bcd(time->tm_year);
  	}

  	return regmap_bulk_write(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);

  }

  /*
   * DS3232 has two alarm, we only use alarm1
   * According to linux specification, only support one-shot alarm
   * no periodic alarm mode
   */
  static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
  {

  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	int control, stat;
  	int ret;
  	u8 buf[4];

  	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
  	if (ret)

  		goto out;

  	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
  	if (ret)

  		goto out;

  	ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
  	if (ret)

  		goto out;
  
  	alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
  	alarm->time.tm_min = bcd2bin(buf[1] & 0x7F);
  	alarm->time.tm_hour = bcd2bin(buf[2] & 0x7F);
  	alarm->time.tm_mday = bcd2bin(buf[3] & 0x7F);

  	alarm->enabled = !!(control & DS3232_REG_CR_A1IE);
  	alarm->pending = !!(stat & DS3232_REG_SR_A1F);
  
  	ret = 0;
  out:

  	return ret;
  }
  
  /*
   * linux rtc-module does not support wday alarm
   * and only 24h time mode supported indeed
   */
  static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
  {

  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	int control, stat;
  	int ret;
  	u8 buf[4];

  	if (ds3232->irq <= 0)

  		return -EINVAL;

  	buf[0] = bin2bcd(alarm->time.tm_sec);
  	buf[1] = bin2bcd(alarm->time.tm_min);
  	buf[2] = bin2bcd(alarm->time.tm_hour);
  	buf[3] = bin2bcd(alarm->time.tm_mday);
  
  	/* clear alarm interrupt enable bit */

  	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
  	if (ret)

  		goto out;

  	control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);

  	ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
  	if (ret)

  		goto out;
  
  	/* clear any pending alarm flag */

  	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
  	if (ret)

  		goto out;

  	stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);

  	ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
  	if (ret)

  		goto out;

  	ret = regmap_bulk_write(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);

  	if (ret)
  		goto out;

  
  	if (alarm->enabled) {
  		control |= DS3232_REG_CR_A1IE;

  		ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);

  	}
  out:

  	return ret;
  }

  static int ds3232_update_alarm(struct device *dev, unsigned int enabled)

  {

  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	int control;
  	int ret;

  	ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
  	if (ret)

  		return ret;

  	if (enabled)

  		/* enable alarm1 interrupt */
  		control |= DS3232_REG_CR_A1IE;
  	else
  		/* disable alarm1 interrupt */
  		control &= ~(DS3232_REG_CR_A1IE);

  	ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);

  	return ret;

  }

  /*
   * Temperature sensor support for ds3232/ds3234 devices.
   * A user-initiated temperature conversion is not started by this function,
   * so the temperature is updated once every 64 seconds.
   */
  static int ds3232_hwmon_read_temp(struct device *dev, long int *mC)
  {
  	struct ds3232 *ds3232 = dev_get_drvdata(dev);
  	u8 temp_buf[2];
  	s16 temp;
  	int ret;
  
  	ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_TEMPERATURE, temp_buf,
  			       sizeof(temp_buf));
  	if (ret < 0)
  		return ret;
  
  	/*
  	 * Temperature is represented as a 10-bit code with a resolution of
  	 * 0.25 degree celsius and encoded in two's complement format.
  	 */
  	temp = (temp_buf[0] << 8) | temp_buf[1];
  	temp >>= 6;
  	*mC = temp * 250;
  
  	return 0;
  }
  
  static umode_t ds3232_hwmon_is_visible(const void *data,
  				       enum hwmon_sensor_types type,
  				       u32 attr, int channel)
  {
  	if (type != hwmon_temp)
  		return 0;
  
  	switch (attr) {
  	case hwmon_temp_input:
  		return 0444;
  	default:
  		return 0;
  	}
  }
  
  static int ds3232_hwmon_read(struct device *dev,
  			     enum hwmon_sensor_types type,
  			     u32 attr, int channel, long *temp)
  {
  	int err;
  
  	switch (attr) {
  	case hwmon_temp_input:
  		err = ds3232_hwmon_read_temp(dev, temp);
  		break;
  	default:
  		err = -EOPNOTSUPP;
  		break;
  	}
  
  	return err;
  }
  
  static u32 ds3232_hwmon_chip_config[] = {
  	HWMON_C_REGISTER_TZ,
  	0
  };
  
  static const struct hwmon_channel_info ds3232_hwmon_chip = {
  	.type = hwmon_chip,
  	.config = ds3232_hwmon_chip_config,
  };
  
  static u32 ds3232_hwmon_temp_config[] = {
  	HWMON_T_INPUT,
  	0
  };
  
  static const struct hwmon_channel_info ds3232_hwmon_temp = {
  	.type = hwmon_temp,
  	.config = ds3232_hwmon_temp_config,
  };
  
  static const struct hwmon_channel_info *ds3232_hwmon_info[] = {
  	&ds3232_hwmon_chip,
  	&ds3232_hwmon_temp,
  	NULL
  };
  
  static const struct hwmon_ops ds3232_hwmon_hwmon_ops = {
  	.is_visible = ds3232_hwmon_is_visible,
  	.read = ds3232_hwmon_read,
  };
  
  static const struct hwmon_chip_info ds3232_hwmon_chip_info = {
  	.ops = &ds3232_hwmon_hwmon_ops,
  	.info = ds3232_hwmon_info,
  };
  
  static void ds3232_hwmon_register(struct device *dev, const char *name)
  {
  	struct ds3232 *ds3232 = dev_get_drvdata(dev);
  	struct device *hwmon_dev;
  
  	if (!IS_ENABLED(CONFIG_RTC_DRV_DS3232_HWMON))
  		return;
  
  	hwmon_dev = devm_hwmon_device_register_with_info(dev, name, ds3232,
  							&ds3232_hwmon_chip_info,
  							NULL);
  	if (IS_ERR(hwmon_dev)) {
  		dev_err(dev, "unable to register hwmon device %ld
  ",
  			PTR_ERR(hwmon_dev));
  	}
  }

  static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled)
  {

  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	if (ds3232->irq <= 0)

  		return -EINVAL;

  	return ds3232_update_alarm(dev, enabled);

  }

  static irqreturn_t ds3232_irq(int irq, void *dev_id)
  {

  	struct device *dev = dev_id;
  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	struct mutex *lock = &ds3232->rtc->ops_lock;

  	int ret;

  	int stat, control;

  	mutex_lock(lock);

  	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
  	if (ret)

  		goto unlock;
  
  	if (stat & DS3232_REG_SR_A1F) {

  		ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
  		if (ret) {

  			dev_warn(ds3232->dev,
  				 "Read Control Register error %d
  ", ret);

  		} else {
  			/* disable alarm1 interrupt */
  			control &= ~(DS3232_REG_CR_A1IE);

  			ret = regmap_write(ds3232->regmap, DS3232_REG_CR,
  					   control);
  			if (ret) {
  				dev_warn(ds3232->dev,
  					 "Write Control Register error %d
  ",
  					 ret);
  				goto unlock;
  			}

  
  			/* clear the alarm pend flag */
  			stat &= ~DS3232_REG_SR_A1F;

  			ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
  			if (ret) {
  				dev_warn(ds3232->dev,
  					 "Write Status Register error %d
  ",
  					 ret);
  				goto unlock;
  			}

  
  			rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);

  		}

  	}

  unlock:

  	mutex_unlock(lock);

  
  	return IRQ_HANDLED;

  }
  
  static const struct rtc_class_ops ds3232_rtc_ops = {
  	.read_time = ds3232_read_time,
  	.set_time = ds3232_set_time,

  	.read_alarm = ds3232_read_alarm,
  	.set_alarm = ds3232_set_alarm,
  	.alarm_irq_enable = ds3232_alarm_irq_enable,

  };

  static int ds3232_nvmem_read(void *priv, unsigned int offset, void *val,
  			     size_t bytes)
  {
  	struct regmap *ds3232_regmap = (struct regmap *)priv;
  
  	return regmap_bulk_read(ds3232_regmap, DS3232_REG_SRAM_START + offset,
  				val, bytes);
  }
  
  static int ds3232_nvmem_write(void *priv, unsigned int offset, void *val,
  			      size_t bytes)
  {
  	struct regmap *ds3232_regmap = (struct regmap *)priv;
  
  	return regmap_bulk_write(ds3232_regmap, DS3232_REG_SRAM_START + offset,
  				 val, bytes);
  }

  static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
  			const char *name)

  {
  	struct ds3232 *ds3232;
  	int ret;

  	struct nvmem_config nvmem_cfg = {
  		.name = "ds3232_sram",
  		.stride = 1,
  		.size = DS3232_REG_SRAM_SIZE,
  		.word_size = 1,
  		.reg_read = ds3232_nvmem_read,
  		.reg_write = ds3232_nvmem_write,
  		.priv = regmap,
  		.type = NVMEM_TYPE_BATTERY_BACKED
  	};

  	ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL);

  	if (!ds3232)
  		return -ENOMEM;

  	ds3232->regmap = regmap;
  	ds3232->irq = irq;
  	ds3232->dev = dev;
  	dev_set_drvdata(dev, ds3232);

  	ret = ds3232_check_rtc_status(dev);

  	if (ret)

  		return ret;

  	if (ds3232->irq > 0)
  		device_init_wakeup(dev, 1);

  	ds3232_hwmon_register(dev, name);

  	ds3232->rtc = devm_rtc_device_register(dev, name, &ds3232_rtc_ops,
  						THIS_MODULE);
  	if (IS_ERR(ds3232->rtc))
  		return PTR_ERR(ds3232->rtc);

  	ret = rtc_nvmem_register(ds3232->rtc, &nvmem_cfg);
  	if(ret)
  		return ret;

  	if (ds3232->irq > 0) {

  		ret = devm_request_threaded_irq(dev, ds3232->irq, NULL,
  						ds3232_irq,
  						IRQF_SHARED | IRQF_ONESHOT,
  						name, dev);

  		if (ret) {

  			device_set_wakeup_capable(dev, 0);

  			ds3232->irq = 0;
  			dev_err(dev, "unable to request IRQ
  ");

  		}

  	}

  	return 0;

  }

  #ifdef CONFIG_PM_SLEEP
  static int ds3232_suspend(struct device *dev)
  {
  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	if (device_may_wakeup(dev)) {
  		if (enable_irq_wake(ds3232->irq))

  			dev_warn_once(dev, "Cannot set wakeup source
  ");

  	}
  
  	return 0;
  }
  
  static int ds3232_resume(struct device *dev)
  {
  	struct ds3232 *ds3232 = dev_get_drvdata(dev);

  	if (device_may_wakeup(dev))
  		disable_irq_wake(ds3232->irq);

  
  	return 0;
  }
  #endif
  
  static const struct dev_pm_ops ds3232_pm_ops = {
  	SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
  };

  #if IS_ENABLED(CONFIG_I2C)

  static int ds3232_i2c_probe(struct i2c_client *client,
  			    const struct i2c_device_id *id)
  {
  	struct regmap *regmap;
  	static const struct regmap_config config = {
  		.reg_bits = 8,
  		.val_bits = 8,

  		.max_register = DS3232_REG_SRAM_END,

  	};
  
  	regmap = devm_regmap_init_i2c(client, &config);
  	if (IS_ERR(regmap)) {
  		dev_err(&client->dev, "%s: regmap allocation failed: %ld
  ",
  			__func__, PTR_ERR(regmap));
  		return PTR_ERR(regmap);
  	}
  
  	return ds3232_probe(&client->dev, regmap, client->irq, client->name);
  }

  static const struct i2c_device_id ds3232_id[] = {
  	{ "ds3232", 0 },
  	{ }
  };
  MODULE_DEVICE_TABLE(i2c, ds3232_id);

  static const struct of_device_id ds3232_of_match[] = {
  	{ .compatible = "dallas,ds3232" },
  	{ }
  };
  MODULE_DEVICE_TABLE(of, ds3232_of_match);

  static struct i2c_driver ds3232_driver = {
  	.driver = {
  		.name = "rtc-ds3232",

  		.of_match_table = of_match_ptr(ds3232_of_match),

  		.pm	= &ds3232_pm_ops,

  	},

  	.probe = ds3232_i2c_probe,

  	.id_table = ds3232_id,
  };

  
  static int ds3232_register_driver(void)
  {
  	return i2c_add_driver(&ds3232_driver);
  }
  
  static void ds3232_unregister_driver(void)
  {
  	i2c_del_driver(&ds3232_driver);
  }
  
  #else
  
  static int ds3232_register_driver(void)
  {
  	return 0;
  }
  
  static void ds3232_unregister_driver(void)
  {
  }
  
  #endif
  
  #if IS_ENABLED(CONFIG_SPI_MASTER)
  
  static int ds3234_probe(struct spi_device *spi)
  {
  	int res;
  	unsigned int tmp;
  	static const struct regmap_config config = {
  		.reg_bits = 8,
  		.val_bits = 8,

  		.max_register = DS3232_REG_SRAM_END,

  		.write_flag_mask = 0x80,
  	};
  	struct regmap *regmap;
  
  	regmap = devm_regmap_init_spi(spi, &config);
  	if (IS_ERR(regmap)) {
  		dev_err(&spi->dev, "%s: regmap allocation failed: %ld
  ",
  			__func__, PTR_ERR(regmap));
  		return PTR_ERR(regmap);
  	}
  
  	spi->mode = SPI_MODE_3;
  	spi->bits_per_word = 8;
  	spi_setup(spi);
  
  	res = regmap_read(regmap, DS3232_REG_SECONDS, &tmp);
  	if (res)
  		return res;
  
  	/* Control settings
  	 *
  	 * CONTROL_REG
  	 * BIT 7	6	5	4	3	2	1	0
  	 *     EOSC	BBSQW	CONV	RS2	RS1	INTCN	A2IE	A1IE
  	 *
  	 *     0	0	0	1	1	1	0	0
  	 *
  	 * CONTROL_STAT_REG
  	 * BIT 7	6	5	4	3	2	1	0
  	 *     OSF	BB32kHz	CRATE1	CRATE0	EN32kHz	BSY	A2F	A1F
  	 *
  	 *     1	0	0	0	1	0	0	0
  	 */
  	res = regmap_read(regmap, DS3232_REG_CR, &tmp);
  	if (res)
  		return res;
  	res = regmap_write(regmap, DS3232_REG_CR, tmp & 0x1c);
  	if (res)
  		return res;
  
  	res = regmap_read(regmap, DS3232_REG_SR, &tmp);
  	if (res)
  		return res;
  	res = regmap_write(regmap, DS3232_REG_SR, tmp & 0x88);
  	if (res)
  		return res;
  
  	/* Print our settings */
  	res = regmap_read(regmap, DS3232_REG_CR, &tmp);
  	if (res)
  		return res;
  	dev_info(&spi->dev, "Control Reg: 0x%02x
  ", tmp);
  
  	res = regmap_read(regmap, DS3232_REG_SR, &tmp);
  	if (res)
  		return res;
  	dev_info(&spi->dev, "Ctrl/Stat Reg: 0x%02x
  ", tmp);
  
  	return ds3232_probe(&spi->dev, regmap, spi->irq, "ds3234");
  }

  static struct spi_driver ds3234_driver = {
  	.driver = {
  		.name	 = "ds3234",
  	},
  	.probe	 = ds3234_probe,

  };
  
  static int ds3234_register_driver(void)
  {
  	return spi_register_driver(&ds3234_driver);
  }
  
  static void ds3234_unregister_driver(void)
  {
  	spi_unregister_driver(&ds3234_driver);
  }
  
  #else
  
  static int ds3234_register_driver(void)
  {
  	return 0;
  }
  
  static void ds3234_unregister_driver(void)
  {
  }
  
  #endif
  
  static int __init ds323x_init(void)
  {
  	int ret;
  
  	ret = ds3232_register_driver();
  	if (ret) {
  		pr_err("Failed to register ds3232 driver: %d
  ", ret);
  		return ret;
  	}
  
  	ret = ds3234_register_driver();
  	if (ret) {
  		pr_err("Failed to register ds3234 driver: %d
  ", ret);
  		ds3232_unregister_driver();
  	}
  
  	return ret;
  }
  module_init(ds323x_init)
  
  static void __exit ds323x_exit(void)
  {
  	ds3234_unregister_driver();
  	ds3232_unregister_driver();
  }
  module_exit(ds323x_exit)

  
  MODULE_AUTHOR("Srikanth Srinivasan <srikanth.srinivasan@freescale.com>");

  MODULE_AUTHOR("Dennis Aberilla <denzzzhome@yahoo.com>");
  MODULE_DESCRIPTION("Maxim/Dallas DS3232/DS3234 RTC Driver");

  MODULE_LICENSE("GPL");

  MODULE_ALIAS("spi:ds3234");