/* NXP PCF50633 RTC Driver
   *
   * (C) 2006-2008 by Openmoko, Inc.
   * Author: Balaji Rao <balajirrao@openmoko.org>
   * All rights reserved.
   *
   * Broken down from monstrous PCF50633 driver mainly by
   * Harald Welte, Andy Green and Werner Almesberger
   *
   *  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/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/device.h>

  #include <linux/slab.h>

  #include <linux/platform_device.h>
  #include <linux/rtc.h>
  #include <linux/bcd.h>
  #include <linux/err.h>
  
  #include <linux/mfd/pcf50633/core.h>
  
  #define PCF50633_REG_RTCSC	0x59 /* Second */
  #define PCF50633_REG_RTCMN	0x5a /* Minute */
  #define PCF50633_REG_RTCHR	0x5b /* Hour */
  #define PCF50633_REG_RTCWD	0x5c /* Weekday */
  #define PCF50633_REG_RTCDT	0x5d /* Day */
  #define PCF50633_REG_RTCMT	0x5e /* Month */
  #define PCF50633_REG_RTCYR	0x5f /* Year */
  #define PCF50633_REG_RTCSCA	0x60 /* Alarm Second */
  #define PCF50633_REG_RTCMNA	0x61 /* Alarm Minute */
  #define PCF50633_REG_RTCHRA	0x62 /* Alarm Hour */
  #define PCF50633_REG_RTCWDA	0x63 /* Alarm Weekday */
  #define PCF50633_REG_RTCDTA	0x64 /* Alarm Day */
  #define PCF50633_REG_RTCMTA	0x65 /* Alarm Month */
  #define PCF50633_REG_RTCYRA	0x66 /* Alarm Year */
  
  enum pcf50633_time_indexes {
  	PCF50633_TI_SEC,
  	PCF50633_TI_MIN,
  	PCF50633_TI_HOUR,
  	PCF50633_TI_WKDAY,
  	PCF50633_TI_DAY,
  	PCF50633_TI_MONTH,
  	PCF50633_TI_YEAR,
  	PCF50633_TI_EXTENT /* always last */
  };
  
  struct pcf50633_time {
  	u_int8_t time[PCF50633_TI_EXTENT];
  };
  
  struct pcf50633_rtc {
  	int alarm_enabled;

  	int alarm_pending;

  
  	struct pcf50633 *pcf;
  	struct rtc_device *rtc_dev;
  };
  
  static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
  {
  	rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
  	rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
  	rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
  	rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
  	rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);

  	rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;

  	rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
  }
  
  static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
  {
  	pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
  	pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
  	pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
  	pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
  	pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);

  	pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);

  	pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
  }
  
  static int
  pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
  {
  	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
  	int err;
  
  	if (enabled)
  		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
  	else
  		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
  
  	if (err < 0)
  		return err;
  
  	rtc->alarm_enabled = enabled;
  
  	return 0;
  }

  static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
  {
  	struct pcf50633_rtc *rtc;
  	struct pcf50633_time pcf_tm;
  	int ret;
  
  	rtc = dev_get_drvdata(dev);
  
  	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
  					    PCF50633_TI_EXTENT,
  					    &pcf_tm.time[0]);
  	if (ret != PCF50633_TI_EXTENT) {
  		dev_err(dev, "Failed to read time
  ");
  		return -EIO;
  	}
  
  	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x
  ",
  		pcf_tm.time[PCF50633_TI_DAY],
  		pcf_tm.time[PCF50633_TI_MONTH],
  		pcf_tm.time[PCF50633_TI_YEAR],
  		pcf_tm.time[PCF50633_TI_HOUR],
  		pcf_tm.time[PCF50633_TI_MIN],
  		pcf_tm.time[PCF50633_TI_SEC]);
  
  	pcf2rtc_time(tm, &pcf_tm);
  
  	dev_dbg(dev, "RTC_TIME: %u.%u.%u %u:%u:%u
  ",
  		tm->tm_mday, tm->tm_mon, tm->tm_year,
  		tm->tm_hour, tm->tm_min, tm->tm_sec);
  
  	return rtc_valid_tm(tm);
  }
  
  static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
  {
  	struct pcf50633_rtc *rtc;
  	struct pcf50633_time pcf_tm;

  	int alarm_masked, ret = 0;

  
  	rtc = dev_get_drvdata(dev);
  
  	dev_dbg(dev, "RTC_TIME: %u.%u.%u %u:%u:%u
  ",
  		tm->tm_mday, tm->tm_mon, tm->tm_year,
  		tm->tm_hour, tm->tm_min, tm->tm_sec);
  
  	rtc2pcf_time(&pcf_tm, tm);
  
  	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x
  ",
  		pcf_tm.time[PCF50633_TI_DAY],
  		pcf_tm.time[PCF50633_TI_MONTH],
  		pcf_tm.time[PCF50633_TI_YEAR],
  		pcf_tm.time[PCF50633_TI_HOUR],
  		pcf_tm.time[PCF50633_TI_MIN],
  		pcf_tm.time[PCF50633_TI_SEC]);

  	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);

  	if (!alarm_masked)
  		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
  
  	/* Returns 0 on success */
  	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
  					     PCF50633_TI_EXTENT,
  					     &pcf_tm.time[0]);

  	if (!alarm_masked)
  		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
  
  	return ret;
  }
  
  static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
  {
  	struct pcf50633_rtc *rtc;
  	struct pcf50633_time pcf_tm;
  	int ret = 0;
  
  	rtc = dev_get_drvdata(dev);
  
  	alrm->enabled = rtc->alarm_enabled;

  	alrm->pending = rtc->alarm_pending;

  
  	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
  				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
  	if (ret != PCF50633_TI_EXTENT) {
  		dev_err(dev, "Failed to read time
  ");
  		return -EIO;
  	}
  
  	pcf2rtc_time(&alrm->time, &pcf_tm);
  
  	return rtc_valid_tm(&alrm->time);
  }
  
  static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
  {
  	struct pcf50633_rtc *rtc;
  	struct pcf50633_time pcf_tm;
  	int alarm_masked, ret = 0;
  
  	rtc = dev_get_drvdata(dev);
  
  	rtc2pcf_time(&pcf_tm, &alrm->time);
  
  	/* do like mktime does and ignore tm_wday */
  	pcf_tm.time[PCF50633_TI_WKDAY] = 7;
  
  	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
  
  	/* disable alarm interrupt */
  	if (!alarm_masked)
  		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
  
  	/* Returns 0 on success */
  	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
  				PCF50633_TI_EXTENT, &pcf_tm.time[0]);

  	if (!alrm->enabled)
  		rtc->alarm_pending = 0;

  	if (!alarm_masked || alrm->enabled)

  		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);

  	rtc->alarm_enabled = alrm->enabled;

  
  	return ret;
  }
  
  static struct rtc_class_ops pcf50633_rtc_ops = {
  	.read_time		= pcf50633_rtc_read_time,
  	.set_time		= pcf50633_rtc_set_time,
  	.read_alarm		= pcf50633_rtc_read_alarm,
  	.set_alarm		= pcf50633_rtc_set_alarm,

  	.alarm_irq_enable	= pcf50633_rtc_alarm_irq_enable,

  };
  
  static void pcf50633_rtc_irq(int irq, void *data)
  {
  	struct pcf50633_rtc *rtc = data;

  	rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
  	rtc->alarm_pending = 1;

  }
  
  static int __devinit pcf50633_rtc_probe(struct platform_device *pdev)
  {

  	struct pcf50633_rtc *rtc;

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

  	rtc->pcf = dev_to_pcf50633(pdev->dev.parent);

  	platform_set_drvdata(pdev, rtc);
  	rtc->rtc_dev = rtc_device_register("pcf50633-rtc", &pdev->dev,
  				&pcf50633_rtc_ops, THIS_MODULE);
  
  	if (IS_ERR(rtc->rtc_dev)) {

  		int ret =  PTR_ERR(rtc->rtc_dev);

  		kfree(rtc);

  		return ret;

  	}
  
  	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
  					pcf50633_rtc_irq, rtc);

  	return 0;
  }
  
  static int __devexit pcf50633_rtc_remove(struct platform_device *pdev)
  {
  	struct pcf50633_rtc *rtc;
  
  	rtc = platform_get_drvdata(pdev);
  
  	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);

  
  	rtc_device_unregister(rtc->rtc_dev);
  	kfree(rtc);
  
  	return 0;
  }
  
  static struct platform_driver pcf50633_rtc_driver = {
  	.driver = {
  		.name = "pcf50633-rtc",
  	},
  	.probe = pcf50633_rtc_probe,
  	.remove = __devexit_p(pcf50633_rtc_remove),
  };

  module_platform_driver(pcf50633_rtc_driver);

  
  MODULE_DESCRIPTION("PCF50633 RTC driver");
  MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
  MODULE_LICENSE("GPL");