[deliverable/linux.git] / drivers / rtc / rtc-davinci.c

/*
 * DaVinci Power Management and Real Time Clock Driver for TI platforms
 *
 * Copyright (C) 2009 Texas Instruments, Inc
 *
 * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>

/*
 * The DaVinci RTC is a simple RTC with the following
 * Sec: 0 - 59 : BCD count
 * Min: 0 - 59 : BCD count
 * Hour: 0 - 23 : BCD count
 * Day: 0 - 0x7FFF(32767) : Binary count ( Over 89 years )
 */

/* PRTC interface registers */
#define DAVINCI_PRTCIF_PID		0x00
#define PRTCIF_CTLR			0x04
#define PRTCIF_LDATA			0x08
#define PRTCIF_UDATA			0x0C
#define PRTCIF_INTEN			0x10
#define PRTCIF_INTFLG			0x14

/* PRTCIF_CTLR bit fields */
#define PRTCIF_CTLR_BUSY		BIT(31)
#define PRTCIF_CTLR_SIZE		BIT(25)
#define PRTCIF_CTLR_DIR			BIT(24)
#define PRTCIF_CTLR_BENU_MSB		BIT(23)
#define PRTCIF_CTLR_BENU_3RD_BYTE	BIT(22)
#define PRTCIF_CTLR_BENU_2ND_BYTE	BIT(21)
#define PRTCIF_CTLR_BENU_LSB		BIT(20)
#define PRTCIF_CTLR_BENU_MASK		(0x00F00000)
#define PRTCIF_CTLR_BENL_MSB		BIT(19)
#define PRTCIF_CTLR_BENL_3RD_BYTE	BIT(18)
#define PRTCIF_CTLR_BENL_2ND_BYTE	BIT(17)
#define PRTCIF_CTLR_BENL_LSB		BIT(16)
#define PRTCIF_CTLR_BENL_MASK		(0x000F0000)

/* PRTCIF_INTEN bit fields */
#define PRTCIF_INTEN_RTCSS		BIT(1)
#define PRTCIF_INTEN_RTCIF		BIT(0)
#define PRTCIF_INTEN_MASK		(PRTCIF_INTEN_RTCSS \
					| PRTCIF_INTEN_RTCIF)

/* PRTCIF_INTFLG bit fields */
#define PRTCIF_INTFLG_RTCSS		BIT(1)
#define PRTCIF_INTFLG_RTCIF		BIT(0)
#define PRTCIF_INTFLG_MASK		(PRTCIF_INTFLG_RTCSS \
					| PRTCIF_INTFLG_RTCIF)

/* PRTC subsystem registers */
#define PRTCSS_RTC_INTC_EXTENA1		(0x0C)
#define PRTCSS_RTC_CTRL			(0x10)
#define PRTCSS_RTC_WDT			(0x11)
#define PRTCSS_RTC_TMR0			(0x12)
#define PRTCSS_RTC_TMR1			(0x13)
#define PRTCSS_RTC_CCTRL		(0x14)
#define PRTCSS_RTC_SEC			(0x15)
#define PRTCSS_RTC_MIN			(0x16)
#define PRTCSS_RTC_HOUR			(0x17)
#define PRTCSS_RTC_DAY0			(0x18)
#define PRTCSS_RTC_DAY1			(0x19)
#define PRTCSS_RTC_AMIN			(0x1A)
#define PRTCSS_RTC_AHOUR		(0x1B)
#define PRTCSS_RTC_ADAY0		(0x1C)
#define PRTCSS_RTC_ADAY1		(0x1D)
#define PRTCSS_RTC_CLKC_CNT		(0x20)

/* PRTCSS_RTC_INTC_EXTENA1 */
#define PRTCSS_RTC_INTC_EXTENA1_MASK	(0x07)

/* PRTCSS_RTC_CTRL bit fields */
#define PRTCSS_RTC_CTRL_WDTBUS		BIT(7)
#define PRTCSS_RTC_CTRL_WEN		BIT(6)
#define PRTCSS_RTC_CTRL_WDRT		BIT(5)
#define PRTCSS_RTC_CTRL_WDTFLG		BIT(4)
#define PRTCSS_RTC_CTRL_TE		BIT(3)
#define PRTCSS_RTC_CTRL_TIEN		BIT(2)
#define PRTCSS_RTC_CTRL_TMRFLG		BIT(1)
#define PRTCSS_RTC_CTRL_TMMD		BIT(0)

/* PRTCSS_RTC_CCTRL bit fields */
#define PRTCSS_RTC_CCTRL_CALBUSY	BIT(7)
#define PRTCSS_RTC_CCTRL_DAEN		BIT(5)
#define PRTCSS_RTC_CCTRL_HAEN		BIT(4)
#define PRTCSS_RTC_CCTRL_MAEN		BIT(3)
#define PRTCSS_RTC_CCTRL_ALMFLG		BIT(2)
#define PRTCSS_RTC_CCTRL_AIEN		BIT(1)
#define PRTCSS_RTC_CCTRL_CAEN		BIT(0)

static DEFINE_SPINLOCK(davinci_rtc_lock);

struct davinci_rtc {
	struct rtc_device		*rtc;
	void __iomem			*base;
	int				irq;
};

static inline void rtcif_write(struct davinci_rtc *davinci_rtc,
			       u32 val, u32 addr)
{
	writel(val, davinci_rtc->base + addr);
}

static inline u32 rtcif_read(struct davinci_rtc *davinci_rtc, u32 addr)
{
	return readl(davinci_rtc->base + addr);
}

static inline void rtcif_wait(struct davinci_rtc *davinci_rtc)
{
	while (rtcif_read(davinci_rtc, PRTCIF_CTLR) & PRTCIF_CTLR_BUSY)
		cpu_relax();
}

static inline void rtcss_write(struct davinci_rtc *davinci_rtc,
			       unsigned long val, u8 addr)
{
	rtcif_wait(davinci_rtc);

	rtcif_write(davinci_rtc, PRTCIF_CTLR_BENL_LSB | addr, PRTCIF_CTLR);
	rtcif_write(davinci_rtc, val, PRTCIF_LDATA);

	rtcif_wait(davinci_rtc);
}

static inline u8 rtcss_read(struct davinci_rtc *davinci_rtc, u8 addr)
{
	rtcif_wait(davinci_rtc);

	rtcif_write(davinci_rtc, PRTCIF_CTLR_DIR | PRTCIF_CTLR_BENL_LSB | addr,
		    PRTCIF_CTLR);

	rtcif_wait(davinci_rtc);

	return rtcif_read(davinci_rtc, PRTCIF_LDATA);
}

static inline void davinci_rtcss_calendar_wait(struct davinci_rtc *davinci_rtc)
{
	while (rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
	       PRTCSS_RTC_CCTRL_CALBUSY)
		cpu_relax();
}

static irqreturn_t davinci_rtc_interrupt(int irq, void *class_dev)
{
	struct davinci_rtc *davinci_rtc = class_dev;
	unsigned long events = 0;
	u32 irq_flg;
	u8 alm_irq, tmr_irq;
	u8 rtc_ctrl, rtc_cctrl;
	int ret = IRQ_NONE;

	irq_flg = rtcif_read(davinci_rtc, PRTCIF_INTFLG) &
		  PRTCIF_INTFLG_RTCSS;

	alm_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
		  PRTCSS_RTC_CCTRL_ALMFLG;

	tmr_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL) &
		  PRTCSS_RTC_CTRL_TMRFLG;

	if (irq_flg) {
		if (alm_irq) {
			events |= RTC_IRQF | RTC_AF;
			rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
			rtc_cctrl |=  PRTCSS_RTC_CCTRL_ALMFLG;
			rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
		} else if (tmr_irq) {
			events |= RTC_IRQF | RTC_PF;
			rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
			rtc_ctrl |=  PRTCSS_RTC_CTRL_TMRFLG;
			rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
		}

		rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS,
				    PRTCIF_INTFLG);
		rtc_update_irq(davinci_rtc->rtc, 1, events);

		ret = IRQ_HANDLED;
	}

	return ret;
}

static int
davinci_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
{
	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
	u8 rtc_ctrl;
	unsigned long flags;
	int ret = 0;

	spin_lock_irqsave(&davinci_rtc_lock, flags);

	rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);

	switch (cmd) {
	case RTC_WIE_ON:
		rtc_ctrl |= PRTCSS_RTC_CTRL_WEN | PRTCSS_RTC_CTRL_WDTFLG;
		break;
	case RTC_WIE_OFF:
		rtc_ctrl &= ~PRTCSS_RTC_CTRL_WEN;
		break;
	default:
		ret = -ENOIOCTLCMD;
	}

	rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);

	spin_unlock_irqrestore(&davinci_rtc_lock, flags);

	return ret;
}

static int convertfromdays(u16 days, struct rtc_time *tm)
{
	int tmp_days, year, mon;

	for (year = 2000;; year++) {
		tmp_days = rtc_year_days(1, 12, year);
		if (days >= tmp_days)
			days -= tmp_days;
		else {
			for (mon = 0;; mon++) {
				tmp_days = rtc_month_days(mon, year);
				if (days >= tmp_days) {
					days -= tmp_days;
				} else {
					tm->tm_year = year - 1900;
					tm->tm_mon = mon;
					tm->tm_mday = days + 1;
					break;
				}
			}
			break;
		}
	}
	return 0;
}

static int convert2days(u16 *days, struct rtc_time *tm)
{
	int i;
	*days = 0;

	/* epoch == 1900 */
	if (tm->tm_year < 100 || tm->tm_year > 199)
		return -EINVAL;

	for (i = 2000; i < 1900 + tm->tm_year; i++)
		*days += rtc_year_days(1, 12, i);

	*days += rtc_year_days(tm->tm_mday, tm->tm_mon, 1900 + tm->tm_year);

	return 0;
}

static int davinci_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
	u16 days = 0;
	u8 day0, day1;
	unsigned long flags;

	spin_lock_irqsave(&davinci_rtc_lock, flags);

	davinci_rtcss_calendar_wait(davinci_rtc);
	tm->tm_sec = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_SEC));

	davinci_rtcss_calendar_wait(davinci_rtc);
	tm->tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_MIN));

	davinci_rtcss_calendar_wait(davinci_rtc);
	tm->tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_HOUR));

	davinci_rtcss_calendar_wait(davinci_rtc);
	day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY0);

	davinci_rtcss_calendar_wait(davinci_rtc);
	day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY1);

	spin_unlock_irqrestore(&davinci_rtc_lock, flags);

	days |= day1;
	days <<= 8;
	days |= day0;

	if (convertfromdays(days, tm) < 0)
		return -EINVAL;

	return 0;
}

static int davinci_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
	u16 days;
	u8 rtc_cctrl;
	unsigned long flags;

	if (convert2days(&days, tm) < 0)
		return -EINVAL;

	spin_lock_irqsave(&davinci_rtc_lock, flags);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, bin2bcd(tm->tm_sec), PRTCSS_RTC_SEC);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, bin2bcd(tm->tm_min), PRTCSS_RTC_MIN);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, bin2bcd(tm->tm_hour), PRTCSS_RTC_HOUR);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_DAY0);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_DAY1);

	rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
	rtc_cctrl |= PRTCSS_RTC_CCTRL_CAEN;
	rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);

	spin_unlock_irqrestore(&davinci_rtc_lock, flags);

	return 0;
}

static int davinci_rtc_alarm_irq_enable(struct device *dev,
					unsigned int enabled)
{
	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
	unsigned long flags;
	u8 rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);

	spin_lock_irqsave(&davinci_rtc_lock, flags);

	if (enabled)
		rtc_cctrl |= PRTCSS_RTC_CCTRL_DAEN |
			     PRTCSS_RTC_CCTRL_HAEN |
			     PRTCSS_RTC_CCTRL_MAEN |
			     PRTCSS_RTC_CCTRL_ALMFLG |
			     PRTCSS_RTC_CCTRL_AIEN;
	else
		rtc_cctrl &= ~PRTCSS_RTC_CCTRL_AIEN;

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);

	spin_unlock_irqrestore(&davinci_rtc_lock, flags);

	return 0;
}

static int davinci_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
	u16 days = 0;
	u8 day0, day1;
	unsigned long flags;

	spin_lock_irqsave(&davinci_rtc_lock, flags);

	davinci_rtcss_calendar_wait(davinci_rtc);
	alm->time.tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AMIN));

	davinci_rtcss_calendar_wait(davinci_rtc);
	alm->time.tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AHOUR));

	davinci_rtcss_calendar_wait(davinci_rtc);
	day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY0);

	davinci_rtcss_calendar_wait(davinci_rtc);
	day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY1);

	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
	days |= day1;
	days <<= 8;
	days |= day0;

	if (convertfromdays(days, &alm->time) < 0)
		return -EINVAL;

	alm->pending = !!(rtcss_read(davinci_rtc,
			  PRTCSS_RTC_CCTRL) &
			PRTCSS_RTC_CCTRL_AIEN);
	alm->enabled = alm->pending && device_may_wakeup(dev);

	return 0;
}

static int davinci_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
	unsigned long flags;
	u16 days;

	if (alm->time.tm_mday <= 0 && alm->time.tm_mon < 0
	    && alm->time.tm_year < 0) {
		struct rtc_time tm;
		unsigned long now, then;

		davinci_rtc_read_time(dev, &tm);
		rtc_tm_to_time(&tm, &now);

		alm->time.tm_mday = tm.tm_mday;
		alm->time.tm_mon = tm.tm_mon;
		alm->time.tm_year = tm.tm_year;
		rtc_tm_to_time(&alm->time, &then);

		if (then < now) {
			rtc_time_to_tm(now + 24 * 60 * 60, &tm);
			alm->time.tm_mday = tm.tm_mday;
			alm->time.tm_mon = tm.tm_mon;
			alm->time.tm_year = tm.tm_year;
		}
	}

	if (convert2days(&days, &alm->time) < 0)
		return -EINVAL;

	spin_lock_irqsave(&davinci_rtc_lock, flags);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_min), PRTCSS_RTC_AMIN);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_hour), PRTCSS_RTC_AHOUR);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_ADAY0);

	davinci_rtcss_calendar_wait(davinci_rtc);
	rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_ADAY1);

	spin_unlock_irqrestore(&davinci_rtc_lock, flags);

	return 0;
}

static struct rtc_class_ops davinci_rtc_ops = {
	.ioctl			= davinci_rtc_ioctl,
	.read_time		= davinci_rtc_read_time,
	.set_time		= davinci_rtc_set_time,
	.alarm_irq_enable	= davinci_rtc_alarm_irq_enable,
	.read_alarm		= davinci_rtc_read_alarm,
	.set_alarm		= davinci_rtc_set_alarm,
};

static int __init davinci_rtc_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct davinci_rtc *davinci_rtc;
	struct resource *res;
	int ret = 0;

	davinci_rtc = devm_kzalloc(&pdev->dev, sizeof(struct davinci_rtc), GFP_KERNEL);
	if (!davinci_rtc)
		return -ENOMEM;

	davinci_rtc->irq = platform_get_irq(pdev, 0);
	if (davinci_rtc->irq < 0) {
		dev_err(dev, "no RTC irq\n");
		return davinci_rtc->irq;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	davinci_rtc->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(davinci_rtc->base))
		return PTR_ERR(davinci_rtc->base);

	platform_set_drvdata(pdev, davinci_rtc);

	davinci_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
				    &davinci_rtc_ops, THIS_MODULE);
	if (IS_ERR(davinci_rtc->rtc)) {
		dev_err(dev, "unable to register RTC device, err %d\n",
				ret);
		return PTR_ERR(davinci_rtc->rtc);
	}

	rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS, PRTCIF_INTFLG);
	rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_INTC_EXTENA1);

	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CTRL);
	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CCTRL);

	ret = devm_request_irq(dev, davinci_rtc->irq, davinci_rtc_interrupt,
			  0, "davinci_rtc", davinci_rtc);
	if (ret < 0) {
		dev_err(dev, "unable to register davinci RTC interrupt\n");
		return ret;
	}

	/* Enable interrupts */
	rtcif_write(davinci_rtc, PRTCIF_INTEN_RTCSS, PRTCIF_INTEN);
	rtcss_write(davinci_rtc, PRTCSS_RTC_INTC_EXTENA1_MASK,
			    PRTCSS_RTC_INTC_EXTENA1);

	rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);

	device_init_wakeup(&pdev->dev, 0);

	return 0;
}

static int __exit davinci_rtc_remove(struct platform_device *pdev)
{
	struct davinci_rtc *davinci_rtc = platform_get_drvdata(pdev);

	device_init_wakeup(&pdev->dev, 0);

	rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);

	return 0;
}

static struct platform_driver davinci_rtc_driver = {
	.probe		= davinci_rtc_probe,
	.remove		= __exit_p(davinci_rtc_remove),
	.driver		= {
		.name = "rtc_davinci",
	},
};

module_platform_driver_probe(davinci_rtc_driver, davinci_rtc_probe);

MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
8ecf6c54 MA	1	/*
	2	* DaVinci Power Management and Real Time Clock Driver for TI platforms
	3	*
	4	* Copyright (C) 2009 Texas Instruments, Inc
	5	*
	6	* Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	21	*/
	22	#include <linux/kernel.h>
	23	#include <linux/init.h>
	24	#include <linux/module.h>
	25	#include <linux/ioport.h>
	26	#include <linux/delay.h>
	27	#include <linux/spinlock.h>
	28	#include <linux/rtc.h>
	29	#include <linux/bcd.h>
	30	#include <linux/platform_device.h>
	31	#include <linux/io.h>
f244f31a	32	#include <linux/slab.h>
8ecf6c54 MA	33
	34	/*
	35	* The DaVinci RTC is a simple RTC with the following
	36	* Sec: 0 - 59 : BCD count
	37	* Min: 0 - 59 : BCD count
	38	* Hour: 0 - 23 : BCD count
	39	* Day: 0 - 0x7FFF(32767) : Binary count ( Over 89 years )
	40	*/
	41
	42	/* PRTC interface registers */
	43	#define DAVINCI_PRTCIF_PID 0x00
	44	#define PRTCIF_CTLR 0x04
	45	#define PRTCIF_LDATA 0x08
	46	#define PRTCIF_UDATA 0x0C
	47	#define PRTCIF_INTEN 0x10
	48	#define PRTCIF_INTFLG 0x14
	49
	50	/* PRTCIF_CTLR bit fields */
	51	#define PRTCIF_CTLR_BUSY BIT(31)
	52	#define PRTCIF_CTLR_SIZE BIT(25)
	53	#define PRTCIF_CTLR_DIR BIT(24)
	54	#define PRTCIF_CTLR_BENU_MSB BIT(23)
	55	#define PRTCIF_CTLR_BENU_3RD_BYTE BIT(22)
	56	#define PRTCIF_CTLR_BENU_2ND_BYTE BIT(21)
	57	#define PRTCIF_CTLR_BENU_LSB BIT(20)
	58	#define PRTCIF_CTLR_BENU_MASK (0x00F00000)
	59	#define PRTCIF_CTLR_BENL_MSB BIT(19)
	60	#define PRTCIF_CTLR_BENL_3RD_BYTE BIT(18)
	61	#define PRTCIF_CTLR_BENL_2ND_BYTE BIT(17)
	62	#define PRTCIF_CTLR_BENL_LSB BIT(16)
	63	#define PRTCIF_CTLR_BENL_MASK (0x000F0000)
	64
	65	/* PRTCIF_INTEN bit fields */
	66	#define PRTCIF_INTEN_RTCSS BIT(1)
	67	#define PRTCIF_INTEN_RTCIF BIT(0)
	68	#define PRTCIF_INTEN_MASK (PRTCIF_INTEN_RTCSS \
	69	\| PRTCIF_INTEN_RTCIF)
	70
	71	/* PRTCIF_INTFLG bit fields */
	72	#define PRTCIF_INTFLG_RTCSS BIT(1)
	73	#define PRTCIF_INTFLG_RTCIF BIT(0)
	74	#define PRTCIF_INTFLG_MASK (PRTCIF_INTFLG_RTCSS \
	75	\| PRTCIF_INTFLG_RTCIF)
	76
	77	/* PRTC subsystem registers */
	78	#define PRTCSS_RTC_INTC_EXTENA1 (0x0C)
	79	#define PRTCSS_RTC_CTRL (0x10)
	80	#define PRTCSS_RTC_WDT (0x11)
	81	#define PRTCSS_RTC_TMR0 (0x12)
	82	#define PRTCSS_RTC_TMR1 (0x13)
	83	#define PRTCSS_RTC_CCTRL (0x14)
	84	#define PRTCSS_RTC_SEC (0x15)
	85	#define PRTCSS_RTC_MIN (0x16)
	86	#define PRTCSS_RTC_HOUR (0x17)
	87	#define PRTCSS_RTC_DAY0 (0x18)
	88	#define PRTCSS_RTC_DAY1 (0x19)
	89	#define PRTCSS_RTC_AMIN (0x1A)
	90	#define PRTCSS_RTC_AHOUR (0x1B)
	91	#define PRTCSS_RTC_ADAY0 (0x1C)
	92	#define PRTCSS_RTC_ADAY1 (0x1D)
	93	#define PRTCSS_RTC_CLKC_CNT (0x20)
	94
	95	/* PRTCSS_RTC_INTC_EXTENA1 */
	96	#define PRTCSS_RTC_INTC_EXTENA1_MASK (0x07)
97
98	/* PRTCSS_RTC_CTRL bit fields */
99	#define PRTCSS_RTC_CTRL_WDTBUS BIT(7)
100	#define PRTCSS_RTC_CTRL_WEN BIT(6)
101	#define PRTCSS_RTC_CTRL_WDRT BIT(5)
102	#define PRTCSS_RTC_CTRL_WDTFLG BIT(4)
103	#define PRTCSS_RTC_CTRL_TE BIT(3)
104	#define PRTCSS_RTC_CTRL_TIEN BIT(2)
105	#define PRTCSS_RTC_CTRL_TMRFLG BIT(1)
106	#define PRTCSS_RTC_CTRL_TMMD BIT(0)
107
108	/* PRTCSS_RTC_CCTRL bit fields */
109	#define PRTCSS_RTC_CCTRL_CALBUSY BIT(7)
110	#define PRTCSS_RTC_CCTRL_DAEN BIT(5)
111	#define PRTCSS_RTC_CCTRL_HAEN BIT(4)
112	#define PRTCSS_RTC_CCTRL_MAEN BIT(3)
113	#define PRTCSS_RTC_CCTRL_ALMFLG BIT(2)
114	#define PRTCSS_RTC_CCTRL_AIEN BIT(1)
115	#define PRTCSS_RTC_CCTRL_CAEN BIT(0)
116
117	static DEFINE_SPINLOCK(davinci_rtc_lock);
118
119	struct davinci_rtc {
48c48180	120	struct rtc_device *rtc;
8ecf6c54	121	void __iomem *base;
8ecf6c54 MA	122	int irq;
	123	};
	124
	125	static inline void rtcif_write(struct davinci_rtc *davinci_rtc,
	126	u32 val, u32 addr)
	127	{
	128	writel(val, davinci_rtc->base + addr);
	129	}
	130
	131	static inline u32 rtcif_read(struct davinci_rtc *davinci_rtc, u32 addr)
	132	{
	133	return readl(davinci_rtc->base + addr);
	134	}
	135
	136	static inline void rtcif_wait(struct davinci_rtc *davinci_rtc)
	137	{
	138	while (rtcif_read(davinci_rtc, PRTCIF_CTLR) & PRTCIF_CTLR_BUSY)
	139	cpu_relax();
	140	}
	141
	142	static inline void rtcss_write(struct davinci_rtc *davinci_rtc,
	143	unsigned long val, u8 addr)
	144	{
	145	rtcif_wait(davinci_rtc);
	146
	147	rtcif_write(davinci_rtc, PRTCIF_CTLR_BENL_LSB \| addr, PRTCIF_CTLR);
	148	rtcif_write(davinci_rtc, val, PRTCIF_LDATA);
	149
	150	rtcif_wait(davinci_rtc);
	151	}
	152
	153	static inline u8 rtcss_read(struct davinci_rtc *davinci_rtc, u8 addr)
	154	{
	155	rtcif_wait(davinci_rtc);
	156
	157	rtcif_write(davinci_rtc, PRTCIF_CTLR_DIR \| PRTCIF_CTLR_BENL_LSB \| addr,
	158	PRTCIF_CTLR);
	159
	160	rtcif_wait(davinci_rtc);
	161
	162	return rtcif_read(davinci_rtc, PRTCIF_LDATA);
	163	}
	164
	165	static inline void davinci_rtcss_calendar_wait(struct davinci_rtc *davinci_rtc)
	166	{
	167	while (rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
	168	PRTCSS_RTC_CCTRL_CALBUSY)
	169	cpu_relax();
	170	}
	171
	172	static irqreturn_t davinci_rtc_interrupt(int irq, void *class_dev)
	173	{
	174	struct davinci_rtc *davinci_rtc = class_dev;
	175	unsigned long events = 0;
	176	u32 irq_flg;
	177	u8 alm_irq, tmr_irq;
	178	u8 rtc_ctrl, rtc_cctrl;
	179	int ret = IRQ_NONE;
	180
	181	irq_flg = rtcif_read(davinci_rtc, PRTCIF_INTFLG) &
	182	PRTCIF_INTFLG_RTCSS;
	183
	184	alm_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL) &
	185	PRTCSS_RTC_CCTRL_ALMFLG;
186
187	tmr_irq = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL) &
188	PRTCSS_RTC_CTRL_TMRFLG;
189
190	if (irq_flg) {
191	if (alm_irq) {
192	events \|= RTC_IRQF \| RTC_AF;
193	rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
194	rtc_cctrl \|= PRTCSS_RTC_CCTRL_ALMFLG;
195	rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
196	} else if (tmr_irq) {
197	events \|= RTC_IRQF \| RTC_PF;
198	rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
199	rtc_ctrl \|= PRTCSS_RTC_CTRL_TMRFLG;
200	rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
201	}
202
203	rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS,
204	PRTCIF_INTFLG);
205	rtc_update_irq(davinci_rtc->rtc, 1, events);
206
207	ret = IRQ_HANDLED;
208	}
209
210	return ret;
211	}
212
213	static int
214	davinci_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
215	{
216	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
217	u8 rtc_ctrl;
218	unsigned long flags;
219	int ret = 0;
220
221	spin_lock_irqsave(&davinci_rtc_lock, flags);
222
223	rtc_ctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CTRL);
224
225	switch (cmd) {
226	case RTC_WIE_ON:
227	rtc_ctrl \|= PRTCSS_RTC_CTRL_WEN \| PRTCSS_RTC_CTRL_WDTFLG;
228	break;
229	case RTC_WIE_OFF:
230	rtc_ctrl &= ~PRTCSS_RTC_CTRL_WEN;
231	break;
8ecf6c54 MA	232	default:
	233	ret = -ENOIOCTLCMD;
	234	}
	235
	236	rtcss_write(davinci_rtc, rtc_ctrl, PRTCSS_RTC_CTRL);
	237
	238	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
	239
	240	return ret;
	241	}
	242
	243	static int convertfromdays(u16 days, struct rtc_time *tm)
	244	{
	245	int tmp_days, year, mon;
	246
	247	for (year = 2000;; year++) {
	248	tmp_days = rtc_year_days(1, 12, year);
	249	if (days >= tmp_days)
	250	days -= tmp_days;
	251	else {
	252	for (mon = 0;; mon++) {
	253	tmp_days = rtc_month_days(mon, year);
	254	if (days >= tmp_days) {
	255	days -= tmp_days;
	256	} else {
	257	tm->tm_year = year - 1900;
	258	tm->tm_mon = mon;
	259	tm->tm_mday = days + 1;
	260	break;
	261	}
	262	}
	263	break;
	264	}
	265	}
	266	return 0;
	267	}
	268
	269	static int convert2days(u16 days, struct rtc_time tm)
	270	{
	271	int i;
	272	*days = 0;
	273
	274	/* epoch == 1900 */
	275	if (tm->tm_year < 100 \|\| tm->tm_year > 199)
	276	return -EINVAL;
	277
	278	for (i = 2000; i < 1900 + tm->tm_year; i++)
	279	*days += rtc_year_days(1, 12, i);
	280
	281	*days += rtc_year_days(tm->tm_mday, tm->tm_mon, 1900 + tm->tm_year);
	282
	283	return 0;
	284	}
	285
	286	static int davinci_rtc_read_time(struct device dev, struct rtc_time tm)
	287	{
	288	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
	289	u16 days = 0;
	290	u8 day0, day1;
	291	unsigned long flags;
	292
	293	spin_lock_irqsave(&davinci_rtc_lock, flags);
	294
	295	davinci_rtcss_calendar_wait(davinci_rtc);
296	tm->tm_sec = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_SEC));
297
298	davinci_rtcss_calendar_wait(davinci_rtc);
299	tm->tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_MIN));
300
301	davinci_rtcss_calendar_wait(davinci_rtc);
302	tm->tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_HOUR));
303
304	davinci_rtcss_calendar_wait(davinci_rtc);
305	day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY0);
306
307	davinci_rtcss_calendar_wait(davinci_rtc);
308	day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_DAY1);
309
310	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
311
312	days \|= day1;
313	days <<= 8;
314	days \|= day0;
315
316	if (convertfromdays(days, tm) < 0)
317	return -EINVAL;
318
319	return 0;
320	}
321
322	static int davinci_rtc_set_time(struct device dev, struct rtc_time tm)
323	{
324	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
325	u16 days;
326	u8 rtc_cctrl;
327	unsigned long flags;
328
329	if (convert2days(&days, tm) < 0)
330	return -EINVAL;
331
332	spin_lock_irqsave(&davinci_rtc_lock, flags);
333
334	davinci_rtcss_calendar_wait(davinci_rtc);
335	rtcss_write(davinci_rtc, bin2bcd(tm->tm_sec), PRTCSS_RTC_SEC);
336
337	davinci_rtcss_calendar_wait(davinci_rtc);
338	rtcss_write(davinci_rtc, bin2bcd(tm->tm_min), PRTCSS_RTC_MIN);
339
340	davinci_rtcss_calendar_wait(davinci_rtc);
341	rtcss_write(davinci_rtc, bin2bcd(tm->tm_hour), PRTCSS_RTC_HOUR);
342
343	davinci_rtcss_calendar_wait(davinci_rtc);
344	rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_DAY0);
345
346	davinci_rtcss_calendar_wait(davinci_rtc);
347	rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_DAY1);
348
349	rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
350	rtc_cctrl \|= PRTCSS_RTC_CCTRL_CAEN;
351	rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
352
353	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
354
355	return 0;
356	}
357
358	static int davinci_rtc_alarm_irq_enable(struct device *dev,
359	unsigned int enabled)
360	{
361	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
362	unsigned long flags;
363	u8 rtc_cctrl = rtcss_read(davinci_rtc, PRTCSS_RTC_CCTRL);
364
365	spin_lock_irqsave(&davinci_rtc_lock, flags);
366
367	if (enabled)
368	rtc_cctrl \|= PRTCSS_RTC_CCTRL_DAEN \|
369	PRTCSS_RTC_CCTRL_HAEN \|
370	PRTCSS_RTC_CCTRL_MAEN \|
371	PRTCSS_RTC_CCTRL_ALMFLG \|
372	PRTCSS_RTC_CCTRL_AIEN;
373	else
374	rtc_cctrl &= ~PRTCSS_RTC_CCTRL_AIEN;
375
376	davinci_rtcss_calendar_wait(davinci_rtc);
377	rtcss_write(davinci_rtc, rtc_cctrl, PRTCSS_RTC_CCTRL);
378
379	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
380
381	return 0;
382	}
383
384	static int davinci_rtc_read_alarm(struct device dev, struct rtc_wkalrm alm)
385	{
386	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
387	u16 days = 0;
388	u8 day0, day1;
389	unsigned long flags;
390
391	spin_lock_irqsave(&davinci_rtc_lock, flags);
392
393	davinci_rtcss_calendar_wait(davinci_rtc);
394	alm->time.tm_min = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AMIN));
395
396	davinci_rtcss_calendar_wait(davinci_rtc);
397	alm->time.tm_hour = bcd2bin(rtcss_read(davinci_rtc, PRTCSS_RTC_AHOUR));
398
399	davinci_rtcss_calendar_wait(davinci_rtc);
400	day0 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY0);
401
402	davinci_rtcss_calendar_wait(davinci_rtc);
403	day1 = rtcss_read(davinci_rtc, PRTCSS_RTC_ADAY1);
404
405	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
406	days \|= day1;
407	days <<= 8;
408	days \|= day0;
409
410	if (convertfromdays(days, &alm->time) < 0)
411	return -EINVAL;
412
413	alm->pending = !!(rtcss_read(davinci_rtc,
414	PRTCSS_RTC_CCTRL) &
415	PRTCSS_RTC_CCTRL_AIEN);
416	alm->enabled = alm->pending && device_may_wakeup(dev);
417
418	return 0;
419	}
420
421	static int davinci_rtc_set_alarm(struct device dev, struct rtc_wkalrm alm)
422	{
423	struct davinci_rtc *davinci_rtc = dev_get_drvdata(dev);
424	unsigned long flags;
425	u16 days;
426
427	if (alm->time.tm_mday <= 0 && alm->time.tm_mon < 0
428	&& alm->time.tm_year < 0) {
429	struct rtc_time tm;
430	unsigned long now, then;
431
432	davinci_rtc_read_time(dev, &tm);
433	rtc_tm_to_time(&tm, &now);
434
435	alm->time.tm_mday = tm.tm_mday;
436	alm->time.tm_mon = tm.tm_mon;
437	alm->time.tm_year = tm.tm_year;
438	rtc_tm_to_time(&alm->time, &then);
439
440	if (then < now) {
441	rtc_time_to_tm(now + 24 * 60 * 60, &tm);
442	alm->time.tm_mday = tm.tm_mday;
443	alm->time.tm_mon = tm.tm_mon;
444	alm->time.tm_year = tm.tm_year;
445	}
446	}
447
448	if (convert2days(&days, &alm->time) < 0)
449	return -EINVAL;
450
451	spin_lock_irqsave(&davinci_rtc_lock, flags);
452
453	davinci_rtcss_calendar_wait(davinci_rtc);
454	rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_min), PRTCSS_RTC_AMIN);
455
456	davinci_rtcss_calendar_wait(davinci_rtc);
457	rtcss_write(davinci_rtc, bin2bcd(alm->time.tm_hour), PRTCSS_RTC_AHOUR);
458
459	davinci_rtcss_calendar_wait(davinci_rtc);
460	rtcss_write(davinci_rtc, days & 0xFF, PRTCSS_RTC_ADAY0);
461
462	davinci_rtcss_calendar_wait(davinci_rtc);
463	rtcss_write(davinci_rtc, (days & 0xFF00) >> 8, PRTCSS_RTC_ADAY1);
464
465	spin_unlock_irqrestore(&davinci_rtc_lock, flags);
466
467	return 0;
468	}
469
8ecf6c54 MA	470	static struct rtc_class_ops davinci_rtc_ops = {
	471	.ioctl = davinci_rtc_ioctl,
	472	.read_time = davinci_rtc_read_time,
	473	.set_time = davinci_rtc_set_time,
	474	.alarm_irq_enable = davinci_rtc_alarm_irq_enable,
	475	.read_alarm = davinci_rtc_read_alarm,
	476	.set_alarm = davinci_rtc_set_alarm,
8ecf6c54 MA	477	};
	478
	479	static int __init davinci_rtc_probe(struct platform_device *pdev)
	480	{
	481	struct device *dev = &pdev->dev;
	482	struct davinci_rtc *davinci_rtc;
1e6789f6	483	struct resource *res;
8ecf6c54 MA	484	int ret = 0;
8ecf6c54 MA	485
f288cf41	486	davinci_rtc = devm_kzalloc(&pdev->dev, sizeof(struct davinci_rtc), GFP_KERNEL);
a3080fa7	487	if (!davinci_rtc)
8ecf6c54	488	return -ENOMEM;
8ecf6c54 MA	489
	490	davinci_rtc->irq = platform_get_irq(pdev, 0);
	491	if (davinci_rtc->irq < 0) {
	492	dev_err(dev, "no RTC irq\n");
f288cf41	493	return davinci_rtc->irq;
8ecf6c54 MA	494	}
	495
	496	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1e6789f6 JH	497	davinci_rtc->base = devm_ioremap_resource(dev, res);
	498	if (IS_ERR(davinci_rtc->base))
	499	return PTR_ERR(davinci_rtc->base);
8ecf6c54	500
f4e708ae WS	501	platform_set_drvdata(pdev, davinci_rtc);
f4e708ae WS	502
8ae236b8	503	davinci_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
8ecf6c54 MA	504	&davinci_rtc_ops, THIS_MODULE);
8ecf6c54 MA	505	if (IS_ERR(davinci_rtc->rtc)) {
9ed39bf9 DN	506	dev_err(dev, "unable to register RTC device, err %d\n",
9ed39bf9 DN	507	ret);
438831fc	508	return PTR_ERR(davinci_rtc->rtc);
8ecf6c54 MA	509	}
	510
	511	rtcif_write(davinci_rtc, PRTCIF_INTFLG_RTCSS, PRTCIF_INTFLG);
	512	rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
	513	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_INTC_EXTENA1);
	514
	515	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CTRL);
	516	rtcss_write(davinci_rtc, 0, PRTCSS_RTC_CCTRL);
	517
a47a376f	518	ret = devm_request_irq(dev, davinci_rtc->irq, davinci_rtc_interrupt,
2f6e5f94	519	0, "davinci_rtc", davinci_rtc);
8ecf6c54 MA	520	if (ret < 0) {
8ecf6c54 MA	521	dev_err(dev, "unable to register davinci RTC interrupt\n");
438831fc	522	return ret;
8ecf6c54 MA	523	}
	524
	525	/* Enable interrupts */
	526	rtcif_write(davinci_rtc, PRTCIF_INTEN_RTCSS, PRTCIF_INTEN);
	527	rtcss_write(davinci_rtc, PRTCSS_RTC_INTC_EXTENA1_MASK,
	528	PRTCSS_RTC_INTC_EXTENA1);
	529
	530	rtcss_write(davinci_rtc, PRTCSS_RTC_CCTRL_CAEN, PRTCSS_RTC_CCTRL);
	531
8ecf6c54 MA	532	device_init_wakeup(&pdev->dev, 0);
	533
	534	return 0;
8ecf6c54 MA	535	}
8ecf6c54 MA	536
5149c035	537	static int __exit davinci_rtc_remove(struct platform_device *pdev)
8ecf6c54 MA	538	{
	539	struct davinci_rtc *davinci_rtc = platform_get_drvdata(pdev);
	540
	541	device_init_wakeup(&pdev->dev, 0);
	542
	543	rtcif_write(davinci_rtc, 0, PRTCIF_INTEN);
	544
8ecf6c54 MA	545	return 0;
	546	}
	547
	548	static struct platform_driver davinci_rtc_driver = {
	549	.probe = davinci_rtc_probe,
5149c035	550	.remove = __exit_p(davinci_rtc_remove),
8ecf6c54 MA	551	.driver = {
8ecf6c54 MA	552	.name = "rtc_davinci",
8ecf6c54 MA	553	},
	554	};
	555
ce14a026	556	module_platform_driver_probe(davinci_rtc_driver, davinci_rtc_probe);
8ecf6c54 MA	557
	558	MODULE_AUTHOR("Miguel Aguilar <miguel.aguilar@ridgerun.com>");
	559	MODULE_DESCRIPTION("Texas Instruments DaVinci PRTC Driver");
	560	MODULE_LICENSE("GPL");