[net-next-2.6.git] / drivers / rtc / rtc-ds1511.c

/*
 * An rtc driver for the Dallas DS1511
 *
 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
 * Copyright (C) 2007 Andrew Sharp <andy.sharp@lsi.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Real time clock driver for the Dallas 1511 chip, which also
 * contains a watchdog timer.  There is a tiny amount of code that
 * platform code could use to mess with the watchdog device a little
 * bit, but not a full watchdog driver.
 */

#include <linux/bcd.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/rtc.h>
#include <linux/platform_device.h>
#include <linux/io.h>

#define DRV_VERSION "0.6"

enum ds1511reg {
	DS1511_SEC = 0x0,
	DS1511_MIN = 0x1,
	DS1511_HOUR = 0x2,
	DS1511_DOW = 0x3,
	DS1511_DOM = 0x4,
	DS1511_MONTH = 0x5,
	DS1511_YEAR = 0x6,
	DS1511_CENTURY = 0x7,
	DS1511_AM1_SEC = 0x8,
	DS1511_AM2_MIN = 0x9,
	DS1511_AM3_HOUR = 0xa,
	DS1511_AM4_DATE = 0xb,
	DS1511_WD_MSEC = 0xc,
	DS1511_WD_SEC = 0xd,
	DS1511_CONTROL_A = 0xe,
	DS1511_CONTROL_B = 0xf,
	DS1511_RAMADDR_LSB = 0x10,
	DS1511_RAMDATA = 0x13
};

#define DS1511_BLF1	0x80
#define DS1511_BLF2	0x40
#define DS1511_PRS	0x20
#define DS1511_PAB	0x10
#define DS1511_TDF	0x08
#define DS1511_KSF	0x04
#define DS1511_WDF	0x02
#define DS1511_IRQF	0x01
#define DS1511_TE	0x80
#define DS1511_CS	0x40
#define DS1511_BME	0x20
#define DS1511_TPE	0x10
#define DS1511_TIE	0x08
#define DS1511_KIE	0x04
#define DS1511_WDE	0x02
#define DS1511_WDS	0x01
#define DS1511_RAM_MAX	0xff

#define RTC_CMD		DS1511_CONTROL_B
#define RTC_CMD1	DS1511_CONTROL_A

#define RTC_ALARM_SEC	DS1511_AM1_SEC
#define RTC_ALARM_MIN	DS1511_AM2_MIN
#define RTC_ALARM_HOUR	DS1511_AM3_HOUR
#define RTC_ALARM_DATE	DS1511_AM4_DATE

#define RTC_SEC		DS1511_SEC
#define RTC_MIN		DS1511_MIN
#define RTC_HOUR	DS1511_HOUR
#define RTC_DOW		DS1511_DOW
#define RTC_DOM		DS1511_DOM
#define RTC_MON		DS1511_MONTH
#define RTC_YEAR	DS1511_YEAR
#define RTC_CENTURY	DS1511_CENTURY

#define RTC_TIE	DS1511_TIE
#define RTC_TE	DS1511_TE

struct rtc_plat_data {
	struct rtc_device *rtc;
	void __iomem *ioaddr;		/* virtual base address */
	int size;				/* amount of memory mapped */
	int irq;
	unsigned int irqen;
	int alrm_sec;
	int alrm_min;
	int alrm_hour;
	int alrm_mday;
	spinlock_t lock;
};

static DEFINE_SPINLOCK(ds1511_lock);

static __iomem char *ds1511_base;
static u32 reg_spacing = 1;

 static noinline void
rtc_write(uint8_t val, uint32_t reg)
{
	writeb(val, ds1511_base + (reg * reg_spacing));
}

 static inline void
rtc_write_alarm(uint8_t val, enum ds1511reg reg)
{
	rtc_write((val | 0x80), reg);
}

 static noinline uint8_t
rtc_read(enum ds1511reg reg)
{
	return readb(ds1511_base + (reg * reg_spacing));
}

 static inline void
rtc_disable_update(void)
{
	rtc_write((rtc_read(RTC_CMD) & ~RTC_TE), RTC_CMD);
}

 static void
rtc_enable_update(void)
{
	rtc_write((rtc_read(RTC_CMD) | RTC_TE), RTC_CMD);
}

/*
 * #define DS1511_WDOG_RESET_SUPPORT
 *
 * Uncomment this if you want to use these routines in
 * some platform code.
 */
#ifdef DS1511_WDOG_RESET_SUPPORT
/*
 * just enough code to set the watchdog timer so that it
 * will reboot the system
 */
 void
ds1511_wdog_set(unsigned long deciseconds)
{
	/*
	 * the wdog timer can take 99.99 seconds
	 */
	deciseconds %= 10000;
	/*
	 * set the wdog values in the wdog registers
	 */
	rtc_write(bin2bcd(deciseconds % 100), DS1511_WD_MSEC);
	rtc_write(bin2bcd(deciseconds / 100), DS1511_WD_SEC);
	/*
	 * set wdog enable and wdog 'steering' bit to issue a reset
	 */
	rtc_write(DS1511_WDE | DS1511_WDS, RTC_CMD);
}

 void
ds1511_wdog_disable(void)
{
	/*
	 * clear wdog enable and wdog 'steering' bits
	 */
	rtc_write(rtc_read(RTC_CMD) & ~(DS1511_WDE | DS1511_WDS), RTC_CMD);
	/*
	 * clear the wdog counter
	 */
	rtc_write(0, DS1511_WD_MSEC);
	rtc_write(0, DS1511_WD_SEC);
}
#endif

/*
 * set the rtc chip's idea of the time.
 * stupidly, some callers call with year unmolested;
 * and some call with  year = year - 1900.  thanks.
 */
static int ds1511_rtc_set_time(struct device *dev, struct rtc_time *rtc_tm)
{
	u8 mon, day, dow, hrs, min, sec, yrs, cen;
	unsigned long flags;

	/*
	 * won't have to change this for a while
	 */
	if (rtc_tm->tm_year < 1900) {
		rtc_tm->tm_year += 1900;
	}

	if (rtc_tm->tm_year < 1970) {
		return -EINVAL;
	}
	yrs = rtc_tm->tm_year % 100;
	cen = rtc_tm->tm_year / 100;
	mon = rtc_tm->tm_mon + 1;   /* tm_mon starts at zero */
	day = rtc_tm->tm_mday;
	dow = rtc_tm->tm_wday & 0x7; /* automatic BCD */
	hrs = rtc_tm->tm_hour;
	min = rtc_tm->tm_min;
	sec = rtc_tm->tm_sec;

	if ((mon > 12) || (day == 0)) {
		return -EINVAL;
	}

	if (day > rtc_month_days(rtc_tm->tm_mon, rtc_tm->tm_year)) {
		return -EINVAL;
	}

	if ((hrs >= 24) || (min >= 60) || (sec >= 60)) {
		return -EINVAL;
	}

	/*
	 * each register is a different number of valid bits
	 */
	sec = bin2bcd(sec) & 0x7f;
	min = bin2bcd(min) & 0x7f;
	hrs = bin2bcd(hrs) & 0x3f;
	day = bin2bcd(day) & 0x3f;
	mon = bin2bcd(mon) & 0x1f;
	yrs = bin2bcd(yrs) & 0xff;
	cen = bin2bcd(cen) & 0xff;

	spin_lock_irqsave(&ds1511_lock, flags);
	rtc_disable_update();
	rtc_write(cen, RTC_CENTURY);
	rtc_write(yrs, RTC_YEAR);
	rtc_write((rtc_read(RTC_MON) & 0xe0) | mon, RTC_MON);
	rtc_write(day, RTC_DOM);
	rtc_write(hrs, RTC_HOUR);
	rtc_write(min, RTC_MIN);
	rtc_write(sec, RTC_SEC);
	rtc_write(dow, RTC_DOW);
	rtc_enable_update();
	spin_unlock_irqrestore(&ds1511_lock, flags);

	return 0;
}

static int ds1511_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)
{
	unsigned int century;
	unsigned long flags;

	spin_lock_irqsave(&ds1511_lock, flags);
	rtc_disable_update();

	rtc_tm->tm_sec = rtc_read(RTC_SEC) & 0x7f;
	rtc_tm->tm_min = rtc_read(RTC_MIN) & 0x7f;
	rtc_tm->tm_hour = rtc_read(RTC_HOUR) & 0x3f;
	rtc_tm->tm_mday = rtc_read(RTC_DOM) & 0x3f;
	rtc_tm->tm_wday = rtc_read(RTC_DOW) & 0x7;
	rtc_tm->tm_mon = rtc_read(RTC_MON) & 0x1f;
	rtc_tm->tm_year = rtc_read(RTC_YEAR) & 0x7f;
	century = rtc_read(RTC_CENTURY);

	rtc_enable_update();
	spin_unlock_irqrestore(&ds1511_lock, flags);

	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
	rtc_tm->tm_wday = bcd2bin(rtc_tm->tm_wday);
	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
	century = bcd2bin(century) * 100;

	/*
	 * Account for differences between how the RTC uses the values
	 * and how they are defined in a struct rtc_time;
	 */
	century += rtc_tm->tm_year;
	rtc_tm->tm_year = century - 1900;

	rtc_tm->tm_mon--;

	if (rtc_valid_tm(rtc_tm) < 0) {
		dev_err(dev, "retrieved date/time is not valid.\n");
		rtc_time_to_tm(0, rtc_tm);
	}
	return 0;
}

/*
 * write the alarm register settings
 *
 * we only have the use to interrupt every second, otherwise
 * known as the update interrupt, or the interrupt if the whole
 * date/hours/mins/secs matches.  the ds1511 has many more
 * permutations, but the kernel doesn't.
 */
 static void
ds1511_rtc_update_alarm(struct rtc_plat_data *pdata)
{
	unsigned long flags;

	spin_lock_irqsave(&pdata->lock, flags);
	rtc_write(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
	       0x80 : bin2bcd(pdata->alrm_mday) & 0x3f,
	       RTC_ALARM_DATE);
	rtc_write(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
	       0x80 : bin2bcd(pdata->alrm_hour) & 0x3f,
	       RTC_ALARM_HOUR);
	rtc_write(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
	       0x80 : bin2bcd(pdata->alrm_min) & 0x7f,
	       RTC_ALARM_MIN);
	rtc_write(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
	       0x80 : bin2bcd(pdata->alrm_sec) & 0x7f,
	       RTC_ALARM_SEC);
	rtc_write(rtc_read(RTC_CMD) | (pdata->irqen ? RTC_TIE : 0), RTC_CMD);
	rtc_read(RTC_CMD1);	/* clear interrupts */
	spin_unlock_irqrestore(&pdata->lock, flags);
}

 static int
ds1511_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);

	if (pdata->irq <= 0)
		return -EINVAL;

	pdata->alrm_mday = alrm->time.tm_mday;
	pdata->alrm_hour = alrm->time.tm_hour;
	pdata->alrm_min = alrm->time.tm_min;
	pdata->alrm_sec = alrm->time.tm_sec;
	if (alrm->enabled) {
		pdata->irqen |= RTC_AF;
	}
	ds1511_rtc_update_alarm(pdata);
	return 0;
}

 static int
ds1511_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);

	if (pdata->irq <= 0)
		return -EINVAL;

	alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
	alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
	alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
	alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
	alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
	return 0;
}

 static irqreturn_t
ds1511_interrupt(int irq, void *dev_id)
{
	struct platform_device *pdev = dev_id;
	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
	unsigned long events = 0;

	spin_lock(&pdata->lock);
	/*
	 * read and clear interrupt
	 */
	if (rtc_read(RTC_CMD1) & DS1511_IRQF) {
		events = RTC_IRQF;
		if (rtc_read(RTC_ALARM_SEC) & 0x80)
			events |= RTC_UF;
		else
			events |= RTC_AF;
		if (likely(pdata->rtc))
			rtc_update_irq(pdata->rtc, 1, events);
	}
	spin_unlock(&pdata->lock);
	return events ? IRQ_HANDLED : IRQ_NONE;
}

static int ds1511_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);

	if (pdata->irq <= 0)
		return -EINVAL;
	if (enabled)
		pdata->irqen |= RTC_AF;
	else
		pdata->irqen &= ~RTC_AF;
	ds1511_rtc_update_alarm(pdata);
	return 0;
}

static int ds1511_rtc_update_irq_enable(struct device *dev,
	unsigned int enabled)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);

	if (pdata->irq <= 0)
		return -EINVAL;
	if (enabled)
		pdata->irqen |= RTC_UF;
	else
		pdata->irqen &= ~RTC_UF;
	ds1511_rtc_update_alarm(pdata);
	return 0;
}

static const struct rtc_class_ops ds1511_rtc_ops = {
	.read_time		= ds1511_rtc_read_time,
	.set_time		= ds1511_rtc_set_time,
	.read_alarm		= ds1511_rtc_read_alarm,
	.set_alarm		= ds1511_rtc_set_alarm,
	.alarm_irq_enable	= ds1511_rtc_alarm_irq_enable,
	.update_irq_enable	= ds1511_rtc_update_irq_enable,
};

 static ssize_t
ds1511_nvram_read(struct kobject *kobj, struct bin_attribute *ba,
				char *buf, loff_t pos, size_t size)
{
	ssize_t count;

	/*
	 * if count is more than one, turn on "burst" mode
	 * turn it off when you're done
	 */
	if (size > 1) {
		rtc_write((rtc_read(RTC_CMD) | DS1511_BME), RTC_CMD);
	}
	if (pos > DS1511_RAM_MAX) {
		pos = DS1511_RAM_MAX;
	}
	if (size + pos > DS1511_RAM_MAX + 1) {
		size = DS1511_RAM_MAX - pos + 1;
	}
	rtc_write(pos, DS1511_RAMADDR_LSB);
	for (count = 0; size > 0; count++, size--) {
		*buf++ = rtc_read(DS1511_RAMDATA);
	}
	if (count > 1) {
		rtc_write((rtc_read(RTC_CMD) & ~DS1511_BME), RTC_CMD);
	}
	return count;
}

 static ssize_t
ds1511_nvram_write(struct kobject *kobj, struct bin_attribute *bin_attr,
				char *buf, loff_t pos, size_t size)
{
	ssize_t count;

	/*
	 * if count is more than one, turn on "burst" mode
	 * turn it off when you're done
	 */
	if (size > 1) {
		rtc_write((rtc_read(RTC_CMD) | DS1511_BME), RTC_CMD);
	}
	if (pos > DS1511_RAM_MAX) {
		pos = DS1511_RAM_MAX;
	}
	if (size + pos > DS1511_RAM_MAX + 1) {
		size = DS1511_RAM_MAX - pos + 1;
	}
	rtc_write(pos, DS1511_RAMADDR_LSB);
	for (count = 0; size > 0; count++, size--) {
		rtc_write(*buf++, DS1511_RAMDATA);
	}
	if (count > 1) {
		rtc_write((rtc_read(RTC_CMD) & ~DS1511_BME), RTC_CMD);
	}
	return count;
}

static struct bin_attribute ds1511_nvram_attr = {
	.attr = {
		.name = "nvram",
		.mode = S_IRUGO | S_IWUGO,
	},
	.size = DS1511_RAM_MAX,
	.read = ds1511_nvram_read,
	.write = ds1511_nvram_write,
};

 static int __devinit
ds1511_rtc_probe(struct platform_device *pdev)
{
	struct rtc_device *rtc;
	struct resource *res;
	struct rtc_plat_data *pdata;
	int ret = 0;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		return -ENODEV;
	}
	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return -ENOMEM;
	pdata->size = res->end - res->start + 1;
	if (!devm_request_mem_region(&pdev->dev, res->start, pdata->size,
			pdev->name))
		return -EBUSY;
	ds1511_base = devm_ioremap(&pdev->dev, res->start, pdata->size);
	if (!ds1511_base)
		return -ENOMEM;
	pdata->ioaddr = ds1511_base;
	pdata->irq = platform_get_irq(pdev, 0);

	/*
	 * turn on the clock and the crystal, etc.
	 */
	rtc_write(0, RTC_CMD);
	rtc_write(0, RTC_CMD1);
	/*
	 * clear the wdog counter
	 */
	rtc_write(0, DS1511_WD_MSEC);
	rtc_write(0, DS1511_WD_SEC);
	/*
	 * start the clock
	 */
	rtc_enable_update();

	/*
	 * check for a dying bat-tree
	 */
	if (rtc_read(RTC_CMD1) & DS1511_BLF1) {
		dev_warn(&pdev->dev, "voltage-low detected.\n");
	}

	spin_lock_init(&pdata->lock);
	platform_set_drvdata(pdev, pdata);
	/*
	 * if the platform has an interrupt in mind for this device,
	 * then by all means, set it
	 */
	if (pdata->irq > 0) {
		rtc_read(RTC_CMD1);
		if (devm_request_irq(&pdev->dev, pdata->irq, ds1511_interrupt,
			IRQF_DISABLED | IRQF_SHARED, pdev->name, pdev) < 0) {

			dev_warn(&pdev->dev, "interrupt not available.\n");
			pdata->irq = 0;
		}
	}

	rtc = rtc_device_register(pdev->name, &pdev->dev, &ds1511_rtc_ops,
		THIS_MODULE);
	if (IS_ERR(rtc))
		return PTR_ERR(rtc);
	pdata->rtc = rtc;

	ret = sysfs_create_bin_file(&pdev->dev.kobj, &ds1511_nvram_attr);
	if (ret)
		rtc_device_unregister(pdata->rtc);
	return ret;
}

 static int __devexit
ds1511_rtc_remove(struct platform_device *pdev)
{
	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);

	sysfs_remove_bin_file(&pdev->dev.kobj, &ds1511_nvram_attr);
	rtc_device_unregister(pdata->rtc);
	if (pdata->irq > 0) {
		/*
		 * disable the alarm interrupt
		 */
		rtc_write(rtc_read(RTC_CMD) & ~RTC_TIE, RTC_CMD);
		rtc_read(RTC_CMD1);
	}
	return 0;
}

/* work with hotplug and coldplug */
MODULE_ALIAS("platform:ds1511");

static struct platform_driver ds1511_rtc_driver = {
	.probe		= ds1511_rtc_probe,
	.remove		= __devexit_p(ds1511_rtc_remove),
	.driver		= {
		.name	= "ds1511",
		.owner	= THIS_MODULE,
	},
};

 static int __init
ds1511_rtc_init(void)
{
	return platform_driver_register(&ds1511_rtc_driver);
}

 static void __exit
ds1511_rtc_exit(void)
{
	platform_driver_unregister(&ds1511_rtc_driver);
}

module_init(ds1511_rtc_init);
module_exit(ds1511_rtc_exit);

MODULE_AUTHOR("Andrew Sharp <andy.sharp@lsi.com>");
MODULE_DESCRIPTION("Dallas DS1511 RTC driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);
Commit	Line	Data
8f26795a AS	1	/*
	2	* An rtc driver for the Dallas DS1511
	3	*
	4	* Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
5b73a41c	5	* Copyright (C) 2007 Andrew Sharp <andy.sharp@lsi.com>
8f26795a AS	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	* Real time clock driver for the Dallas 1511 chip, which also
	12	* contains a watchdog timer. There is a tiny amount of code that
	13	* platform code could use to mess with the watchdog device a little
	14	* bit, but not a full watchdog driver.
	15	*/
	16
	17	#include <linux/bcd.h>
	18	#include <linux/init.h>
	19	#include <linux/kernel.h>
5a0e3ad6	20	#include <linux/gfp.h>
8f26795a AS	21	#include <linux/delay.h>
	22	#include <linux/interrupt.h>
	23	#include <linux/rtc.h>
	24	#include <linux/platform_device.h>
	25	#include <linux/io.h>
	26
	27	#define DRV_VERSION "0.6"
	28
	29	enum ds1511reg {
	30	DS1511_SEC = 0x0,
	31	DS1511_MIN = 0x1,
	32	DS1511_HOUR = 0x2,
	33	DS1511_DOW = 0x3,
	34	DS1511_DOM = 0x4,
	35	DS1511_MONTH = 0x5,
	36	DS1511_YEAR = 0x6,
	37	DS1511_CENTURY = 0x7,
	38	DS1511_AM1_SEC = 0x8,
	39	DS1511_AM2_MIN = 0x9,
	40	DS1511_AM3_HOUR = 0xa,
	41	DS1511_AM4_DATE = 0xb,
	42	DS1511_WD_MSEC = 0xc,
	43	DS1511_WD_SEC = 0xd,
	44	DS1511_CONTROL_A = 0xe,
	45	DS1511_CONTROL_B = 0xf,
	46	DS1511_RAMADDR_LSB = 0x10,
	47	DS1511_RAMDATA = 0x13
	48	};
	49
	50	#define DS1511_BLF1 0x80
	51	#define DS1511_BLF2 0x40
	52	#define DS1511_PRS 0x20
	53	#define DS1511_PAB 0x10
	54	#define DS1511_TDF 0x08
	55	#define DS1511_KSF 0x04
	56	#define DS1511_WDF 0x02
	57	#define DS1511_IRQF 0x01
	58	#define DS1511_TE 0x80
	59	#define DS1511_CS 0x40
	60	#define DS1511_BME 0x20
	61	#define DS1511_TPE 0x10
	62	#define DS1511_TIE 0x08
	63	#define DS1511_KIE 0x04
	64	#define DS1511_WDE 0x02
	65	#define DS1511_WDS 0x01
	66	#define DS1511_RAM_MAX 0xff
	67
	68	#define RTC_CMD DS1511_CONTROL_B
	69	#define RTC_CMD1 DS1511_CONTROL_A
	70
	71	#define RTC_ALARM_SEC DS1511_AM1_SEC
	72	#define RTC_ALARM_MIN DS1511_AM2_MIN
	73	#define RTC_ALARM_HOUR DS1511_AM3_HOUR
	74	#define RTC_ALARM_DATE DS1511_AM4_DATE
	75
	76	#define RTC_SEC DS1511_SEC
	77	#define RTC_MIN DS1511_MIN
	78	#define RTC_HOUR DS1511_HOUR
	79	#define RTC_DOW DS1511_DOW
	80	#define RTC_DOM DS1511_DOM
	81	#define RTC_MON DS1511_MONTH
	82	#define RTC_YEAR DS1511_YEAR
	83	#define RTC_CENTURY DS1511_CENTURY
	84
85	#define RTC_TIE DS1511_TIE
86	#define RTC_TE DS1511_TE
87
88	struct rtc_plat_data {
89	struct rtc_device *rtc;
90	void __iomem ioaddr; / virtual base address */
8f26795a AS	91	int size; /* amount of memory mapped */
	92	int irq;
	93	unsigned int irqen;
	94	int alrm_sec;
	95	int alrm_min;
	96	int alrm_hour;
	97	int alrm_mday;
ba4f3e47	98	spinlock_t lock;
8f26795a AS	99	};
	100
	101	static DEFINE_SPINLOCK(ds1511_lock);
	102
	103	static __iomem char *ds1511_base;
	104	static u32 reg_spacing = 1;
	105
	106	static noinline void
	107	rtc_write(uint8_t val, uint32_t reg)
	108	{
	109	writeb(val, ds1511_base + (reg * reg_spacing));
	110	}
	111
	112	static inline void
	113	rtc_write_alarm(uint8_t val, enum ds1511reg reg)
	114	{
	115	rtc_write((val \| 0x80), reg);
	116	}
	117
	118	static noinline uint8_t
	119	rtc_read(enum ds1511reg reg)
	120	{
	121	return readb(ds1511_base + (reg * reg_spacing));
	122	}
	123
	124	static inline void
	125	rtc_disable_update(void)
	126	{
	127	rtc_write((rtc_read(RTC_CMD) & ~RTC_TE), RTC_CMD);
	128	}
	129
	130	static void
	131	rtc_enable_update(void)
	132	{
	133	rtc_write((rtc_read(RTC_CMD) \| RTC_TE), RTC_CMD);
	134	}
	135
	136	/*
	137	* #define DS1511_WDOG_RESET_SUPPORT
	138	*
	139	* Uncomment this if you want to use these routines in
	140	* some platform code.
	141	*/
	142	#ifdef DS1511_WDOG_RESET_SUPPORT
	143	/*
	144	* just enough code to set the watchdog timer so that it
	145	* will reboot the system
	146	*/
	147	void
	148	ds1511_wdog_set(unsigned long deciseconds)
	149	{
	150	/*
	151	* the wdog timer can take 99.99 seconds
	152	*/
	153	deciseconds %= 10000;
	154	/*
	155	* set the wdog values in the wdog registers
	156	*/
fe20ba70 AB	157	rtc_write(bin2bcd(deciseconds % 100), DS1511_WD_MSEC);
fe20ba70 AB	158	rtc_write(bin2bcd(deciseconds / 100), DS1511_WD_SEC);
8f26795a AS	159	/*
	160	* set wdog enable and wdog 'steering' bit to issue a reset
	161	*/
	162	rtc_write(DS1511_WDE \| DS1511_WDS, RTC_CMD);
	163	}
	164
	165	void
	166	ds1511_wdog_disable(void)
	167	{
	168	/*
	169	* clear wdog enable and wdog 'steering' bits
	170	*/
	171	rtc_write(rtc_read(RTC_CMD) & ~(DS1511_WDE \| DS1511_WDS), RTC_CMD);
	172	/*
	173	* clear the wdog counter
	174	*/
	175	rtc_write(0, DS1511_WD_MSEC);
	176	rtc_write(0, DS1511_WD_SEC);
	177	}
	178	#endif
	179
	180	/*
	181	* set the rtc chip's idea of the time.
	182	* stupidly, some callers call with year unmolested;
	183	* and some call with year = year - 1900. thanks.
	184	*/
a3ed107e	185	static int ds1511_rtc_set_time(struct device dev, struct rtc_time rtc_tm)
8f26795a AS	186	{
8f26795a AS	187	u8 mon, day, dow, hrs, min, sec, yrs, cen;
9a0f4aea	188	unsigned long flags;
8f26795a AS	189
	190	/*
	191	* won't have to change this for a while
	192	*/
	193	if (rtc_tm->tm_year < 1900) {
	194	rtc_tm->tm_year += 1900;
	195	}
	196
	197	if (rtc_tm->tm_year < 1970) {
	198	return -EINVAL;
	199	}
	200	yrs = rtc_tm->tm_year % 100;
	201	cen = rtc_tm->tm_year / 100;
	202	mon = rtc_tm->tm_mon + 1; /* tm_mon starts at zero */
	203	day = rtc_tm->tm_mday;
	204	dow = rtc_tm->tm_wday & 0x7; /* automatic BCD */
	205	hrs = rtc_tm->tm_hour;
	206	min = rtc_tm->tm_min;
	207	sec = rtc_tm->tm_sec;
	208
	209	if ((mon > 12) \|\| (day == 0)) {
	210	return -EINVAL;
	211	}
	212
	213	if (day > rtc_month_days(rtc_tm->tm_mon, rtc_tm->tm_year)) {
	214	return -EINVAL;
	215	}
	216
	217	if ((hrs >= 24) \|\| (min >= 60) \|\| (sec >= 60)) {
	218	return -EINVAL;
	219	}
	220
	221	/*
	222	* each register is a different number of valid bits
	223	*/
fe20ba70 AB	224	sec = bin2bcd(sec) & 0x7f;
	225	min = bin2bcd(min) & 0x7f;
	226	hrs = bin2bcd(hrs) & 0x3f;
	227	day = bin2bcd(day) & 0x3f;
	228	mon = bin2bcd(mon) & 0x1f;
	229	yrs = bin2bcd(yrs) & 0xff;
	230	cen = bin2bcd(cen) & 0xff;
8f26795a AS	231
	232	spin_lock_irqsave(&ds1511_lock, flags);
	233	rtc_disable_update();
	234	rtc_write(cen, RTC_CENTURY);
	235	rtc_write(yrs, RTC_YEAR);
	236	rtc_write((rtc_read(RTC_MON) & 0xe0) \| mon, RTC_MON);
	237	rtc_write(day, RTC_DOM);
	238	rtc_write(hrs, RTC_HOUR);
	239	rtc_write(min, RTC_MIN);
	240	rtc_write(sec, RTC_SEC);
	241	rtc_write(dow, RTC_DOW);
	242	rtc_enable_update();
	243	spin_unlock_irqrestore(&ds1511_lock, flags);
	244
	245	return 0;
	246	}
	247
a3ed107e	248	static int ds1511_rtc_read_time(struct device dev, struct rtc_time rtc_tm)
8f26795a AS	249	{
8f26795a AS	250	unsigned int century;
9a0f4aea	251	unsigned long flags;
8f26795a AS	252
	253	spin_lock_irqsave(&ds1511_lock, flags);
	254	rtc_disable_update();
	255
	256	rtc_tm->tm_sec = rtc_read(RTC_SEC) & 0x7f;
	257	rtc_tm->tm_min = rtc_read(RTC_MIN) & 0x7f;
	258	rtc_tm->tm_hour = rtc_read(RTC_HOUR) & 0x3f;
	259	rtc_tm->tm_mday = rtc_read(RTC_DOM) & 0x3f;
	260	rtc_tm->tm_wday = rtc_read(RTC_DOW) & 0x7;
	261	rtc_tm->tm_mon = rtc_read(RTC_MON) & 0x1f;
	262	rtc_tm->tm_year = rtc_read(RTC_YEAR) & 0x7f;
	263	century = rtc_read(RTC_CENTURY);
	264
	265	rtc_enable_update();
	266	spin_unlock_irqrestore(&ds1511_lock, flags);
	267
fe20ba70 AB	268	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
	269	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
	270	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
	271	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
	272	rtc_tm->tm_wday = bcd2bin(rtc_tm->tm_wday);
	273	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon);
	274	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
	275	century = bcd2bin(century) * 100;
8f26795a AS	276
	277	/*
	278	* Account for differences between how the RTC uses the values
	279	* and how they are defined in a struct rtc_time;
	280	*/
	281	century += rtc_tm->tm_year;
	282	rtc_tm->tm_year = century - 1900;
	283
	284	rtc_tm->tm_mon--;
	285
	286	if (rtc_valid_tm(rtc_tm) < 0) {
	287	dev_err(dev, "retrieved date/time is not valid.\n");
	288	rtc_time_to_tm(0, rtc_tm);
	289	}
	290	return 0;
	291	}
	292
	293	/*
	294	* write the alarm register settings
	295	*
	296	* we only have the use to interrupt every second, otherwise
	297	* known as the update interrupt, or the interrupt if the whole
	298	* date/hours/mins/secs matches. the ds1511 has many more
	299	* permutations, but the kernel doesn't.
	300	*/
	301	static void
	302	ds1511_rtc_update_alarm(struct rtc_plat_data *pdata)
	303	{
	304	unsigned long flags;
	305
ba4f3e47	306	spin_lock_irqsave(&pdata->lock, flags);
8f26795a	307	rtc_write(pdata->alrm_mday < 0 \|\| (pdata->irqen & RTC_UF) ?
fe20ba70	308	0x80 : bin2bcd(pdata->alrm_mday) & 0x3f,
8f26795a AS	309	RTC_ALARM_DATE);
8f26795a AS	310	rtc_write(pdata->alrm_hour < 0 \|\| (pdata->irqen & RTC_UF) ?
fe20ba70	311	0x80 : bin2bcd(pdata->alrm_hour) & 0x3f,
8f26795a AS	312	RTC_ALARM_HOUR);
8f26795a AS	313	rtc_write(pdata->alrm_min < 0 \|\| (pdata->irqen & RTC_UF) ?
fe20ba70	314	0x80 : bin2bcd(pdata->alrm_min) & 0x7f,
8f26795a AS	315	RTC_ALARM_MIN);
8f26795a AS	316	rtc_write(pdata->alrm_sec < 0 \|\| (pdata->irqen & RTC_UF) ?
fe20ba70	317	0x80 : bin2bcd(pdata->alrm_sec) & 0x7f,
8f26795a AS	318	RTC_ALARM_SEC);
	319	rtc_write(rtc_read(RTC_CMD) \| (pdata->irqen ? RTC_TIE : 0), RTC_CMD);
	320	rtc_read(RTC_CMD1); /* clear interrupts */
ba4f3e47	321	spin_unlock_irqrestore(&pdata->lock, flags);
8f26795a AS	322	}
	323
	324	static int
	325	ds1511_rtc_set_alarm(struct device dev, struct rtc_wkalrm alrm)
	326	{
	327	struct platform_device *pdev = to_platform_device(dev);
	328	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
	329
2fac6674	330	if (pdata->irq <= 0)
8f26795a	331	return -EINVAL;
2fac6674	332
8f26795a AS	333	pdata->alrm_mday = alrm->time.tm_mday;
	334	pdata->alrm_hour = alrm->time.tm_hour;
	335	pdata->alrm_min = alrm->time.tm_min;
	336	pdata->alrm_sec = alrm->time.tm_sec;
	337	if (alrm->enabled) {
	338	pdata->irqen \|= RTC_AF;
	339	}
	340	ds1511_rtc_update_alarm(pdata);
	341	return 0;
	342	}
	343
	344	static int
	345	ds1511_rtc_read_alarm(struct device dev, struct rtc_wkalrm alrm)
	346	{
	347	struct platform_device *pdev = to_platform_device(dev);
	348	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
	349
2fac6674	350	if (pdata->irq <= 0)
8f26795a	351	return -EINVAL;
2fac6674	352
8f26795a AS	353	alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
	354	alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
	355	alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
	356	alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
	357	alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
	358	return 0;
	359	}
	360
	361	static irqreturn_t
	362	ds1511_interrupt(int irq, void *dev_id)
	363	{
	364	struct platform_device *pdev = dev_id;
	365	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
ba4f3e47	366	unsigned long events = 0;
8f26795a	367
ba4f3e47	368	spin_lock(&pdata->lock);
8f26795a AS	369	/*
	370	* read and clear interrupt
	371	*/
ba4f3e47 AN	372	if (rtc_read(RTC_CMD1) & DS1511_IRQF) {
	373	events = RTC_IRQF;
	374	if (rtc_read(RTC_ALARM_SEC) & 0x80)
	375	events \|= RTC_UF;
	376	else
	377	events \|= RTC_AF;
	378	if (likely(pdata->rtc))
	379	rtc_update_irq(pdata->rtc, 1, events);
	380	}
	381	spin_unlock(&pdata->lock);
	382	return events ? IRQ_HANDLED : IRQ_NONE;
8f26795a AS	383	}
8f26795a AS	384
ba4f3e47	385	static int ds1511_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
8f26795a AS	386	{
	387	struct platform_device *pdev = to_platform_device(dev);
	388	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
	389
ba4f3e47 AN	390	if (pdata->irq <= 0)
	391	return -EINVAL;
	392	if (enabled)
8f26795a	393	pdata->irqen \|= RTC_AF;
ba4f3e47 AN	394	else
	395	pdata->irqen &= ~RTC_AF;
	396	ds1511_rtc_update_alarm(pdata);
	397	return 0;
	398	}
	399
	400	static int ds1511_rtc_update_irq_enable(struct device *dev,
	401	unsigned int enabled)
	402	{
	403	struct platform_device *pdev = to_platform_device(dev);
	404	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
	405
	406	if (pdata->irq <= 0)
	407	return -EINVAL;
	408	if (enabled)
8f26795a	409	pdata->irqen \|= RTC_UF;
ba4f3e47 AN	410	else
	411	pdata->irqen &= ~RTC_UF;
	412	ds1511_rtc_update_alarm(pdata);
8f26795a AS	413	return 0;
	414	}
	415
	416	static const struct rtc_class_ops ds1511_rtc_ops = {
ba4f3e47 AN	417	.read_time = ds1511_rtc_read_time,
	418	.set_time = ds1511_rtc_set_time,
	419	.read_alarm = ds1511_rtc_read_alarm,
	420	.set_alarm = ds1511_rtc_set_alarm,
	421	.alarm_irq_enable = ds1511_rtc_alarm_irq_enable,
	422	.update_irq_enable = ds1511_rtc_update_irq_enable,
8f26795a AS	423	};
	424
	425	static ssize_t
	426	ds1511_nvram_read(struct kobject kobj, struct bin_attribute ba,
	427	char *buf, loff_t pos, size_t size)
	428	{
	429	ssize_t count;
	430
	431	/*
	432	* if count is more than one, turn on "burst" mode
	433	* turn it off when you're done
	434	*/
	435	if (size > 1) {
	436	rtc_write((rtc_read(RTC_CMD) \| DS1511_BME), RTC_CMD);
	437	}
	438	if (pos > DS1511_RAM_MAX) {
	439	pos = DS1511_RAM_MAX;
	440	}
	441	if (size + pos > DS1511_RAM_MAX + 1) {
	442	size = DS1511_RAM_MAX - pos + 1;
	443	}
	444	rtc_write(pos, DS1511_RAMADDR_LSB);
	445	for (count = 0; size > 0; count++, size--) {
	446	*buf++ = rtc_read(DS1511_RAMDATA);
	447	}
	448	if (count > 1) {
	449	rtc_write((rtc_read(RTC_CMD) & ~DS1511_BME), RTC_CMD);
	450	}
	451	return count;
	452	}
	453
	454	static ssize_t
	455	ds1511_nvram_write(struct kobject kobj, struct bin_attribute bin_attr,
	456	char *buf, loff_t pos, size_t size)
	457	{
	458	ssize_t count;
	459
	460	/*
	461	* if count is more than one, turn on "burst" mode
	462	* turn it off when you're done
	463	*/
	464	if (size > 1) {
	465	rtc_write((rtc_read(RTC_CMD) \| DS1511_BME), RTC_CMD);
	466	}
	467	if (pos > DS1511_RAM_MAX) {
	468	pos = DS1511_RAM_MAX;
	469	}
	470	if (size + pos > DS1511_RAM_MAX + 1) {
	471	size = DS1511_RAM_MAX - pos + 1;
	472	}
	473	rtc_write(pos, DS1511_RAMADDR_LSB);
	474	for (count = 0; size > 0; count++, size--) {
	475	rtc_write(*buf++, DS1511_RAMDATA);
	476	}
	477	if (count > 1) {
	478	rtc_write((rtc_read(RTC_CMD) & ~DS1511_BME), RTC_CMD);
	479	}
	480	return count;
	481	}
	482
	483	static struct bin_attribute ds1511_nvram_attr = {
	484	.attr = {
	485	.name = "nvram",
	486	.mode = S_IRUGO \| S_IWUGO,
8f26795a AS	487	},
	488	.size = DS1511_RAM_MAX,
	489	.read = ds1511_nvram_read,
	490	.write = ds1511_nvram_write,
	491	};
	492
	493	static int __devinit
	494	ds1511_rtc_probe(struct platform_device *pdev)
	495	{
	496	struct rtc_device *rtc;
	497	struct resource *res;
ba4f3e47	498	struct rtc_plat_data *pdata;
8f26795a AS	499	int ret = 0;
	500
	501	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	502	if (!res) {
	503	return -ENODEV;
	504	}
ba4f3e47 AN	505	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
ba4f3e47 AN	506	if (!pdata)
8f26795a	507	return -ENOMEM;
8f26795a	508	pdata->size = res->end - res->start + 1;
ba4f3e47 AN	509	if (!devm_request_mem_region(&pdev->dev, res->start, pdata->size,
	510	pdev->name))
	511	return -EBUSY;
	512	ds1511_base = devm_ioremap(&pdev->dev, res->start, pdata->size);
	513	if (!ds1511_base)
	514	return -ENOMEM;
8f26795a AS	515	pdata->ioaddr = ds1511_base;
	516	pdata->irq = platform_get_irq(pdev, 0);
	517
	518	/*
	519	* turn on the clock and the crystal, etc.
	520	*/
	521	rtc_write(0, RTC_CMD);
	522	rtc_write(0, RTC_CMD1);
	523	/*
	524	* clear the wdog counter
	525	*/
	526	rtc_write(0, DS1511_WD_MSEC);
	527	rtc_write(0, DS1511_WD_SEC);
	528	/*
	529	* start the clock
	530	*/
	531	rtc_enable_update();
	532
	533	/*
	534	* check for a dying bat-tree
	535	*/
	536	if (rtc_read(RTC_CMD1) & DS1511_BLF1) {
	537	dev_warn(&pdev->dev, "voltage-low detected.\n");
	538	}
	539
ba4f3e47 AN	540	spin_lock_init(&pdata->lock);
ba4f3e47 AN	541	platform_set_drvdata(pdev, pdata);
8f26795a AS	542	/*
	543	* if the platform has an interrupt in mind for this device,
	544	* then by all means, set it
	545	*/
2fac6674	546	if (pdata->irq > 0) {
8f26795a	547	rtc_read(RTC_CMD1);
ba4f3e47	548	if (devm_request_irq(&pdev->dev, pdata->irq, ds1511_interrupt,
8f26795a AS	549	IRQF_DISABLED \| IRQF_SHARED, pdev->name, pdev) < 0) {
	550
	551	dev_warn(&pdev->dev, "interrupt not available.\n");
2fac6674	552	pdata->irq = 0;
8f26795a AS	553	}
	554	}
	555
	556	rtc = rtc_device_register(pdev->name, &pdev->dev, &ds1511_rtc_ops,
	557	THIS_MODULE);
ba4f3e47 AN	558	if (IS_ERR(rtc))
ba4f3e47 AN	559	return PTR_ERR(rtc);
8f26795a	560	pdata->rtc = rtc;
ba4f3e47	561
8f26795a	562	ret = sysfs_create_bin_file(&pdev->dev.kobj, &ds1511_nvram_attr);
ba4f3e47	563	if (ret)
8f26795a	564	rtc_device_unregister(pdata->rtc);
8f26795a AS	565	return ret;
	566	}
	567
	568	static int __devexit
	569	ds1511_rtc_remove(struct platform_device *pdev)
	570	{
	571	struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
	572
	573	sysfs_remove_bin_file(&pdev->dev.kobj, &ds1511_nvram_attr);
	574	rtc_device_unregister(pdata->rtc);
2fac6674	575	if (pdata->irq > 0) {
8f26795a AS	576	/*
	577	* disable the alarm interrupt
	578	*/
	579	rtc_write(rtc_read(RTC_CMD) & ~RTC_TIE, RTC_CMD);
	580	rtc_read(RTC_CMD1);
8f26795a	581	}
8f26795a AS	582	return 0;
	583	}
	584
ad28a07b KS	585	/* work with hotplug and coldplug */
	586	MODULE_ALIAS("platform:ds1511");
	587
8f26795a AS	588	static struct platform_driver ds1511_rtc_driver = {
	589	.probe = ds1511_rtc_probe,
	590	.remove = __devexit_p(ds1511_rtc_remove),
	591	.driver = {
	592	.name = "ds1511",
	593	.owner = THIS_MODULE,
	594	},
	595	};
	596
	597	static int __init
	598	ds1511_rtc_init(void)
	599	{
	600	return platform_driver_register(&ds1511_rtc_driver);
	601	}
	602
	603	static void __exit
	604	ds1511_rtc_exit(void)
	605	{
4367fa51	606	platform_driver_unregister(&ds1511_rtc_driver);
8f26795a AS	607	}
	608
	609	module_init(ds1511_rtc_init);
	610	module_exit(ds1511_rtc_exit);
	611
5b73a41c	612	MODULE_AUTHOR("Andrew Sharp <andy.sharp@lsi.com>");
8f26795a AS	613	MODULE_DESCRIPTION("Dallas DS1511 RTC driver");
	614	MODULE_LICENSE("GPL");
	615	MODULE_VERSION(DRV_VERSION);