[mirror_ubuntu-bionic-kernel.git] / drivers / rtc / rtc-pl031.c

/*
 * drivers/rtc/rtc-pl031.c
 *
 * Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
 *
 * Author: Deepak Saxena <dsaxena@plexity.net>
 *
 * Copyright 2006 (c) MontaVista Software, Inc.
 *
 * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
 * Copyright 2010 (c) ST-Ericsson AB
 *
 * 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/module.h>
#include <linux/rtc.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/amba/bus.h>
#include <linux/io.h>
#include <linux/bcd.h>
#include <linux/delay.h>
#include <linux/pm_wakeirq.h>
#include <linux/slab.h>

/*
 * Register definitions
 */
#define	RTC_DR		0x00	/* Data read register */
#define	RTC_MR		0x04	/* Match register */
#define	RTC_LR		0x08	/* Data load register */
#define	RTC_CR		0x0c	/* Control register */
#define	RTC_IMSC	0x10	/* Interrupt mask and set register */
#define	RTC_RIS		0x14	/* Raw interrupt status register */
#define	RTC_MIS		0x18	/* Masked interrupt status register */
#define	RTC_ICR		0x1c	/* Interrupt clear register */
/* ST variants have additional timer functionality */
#define RTC_TDR		0x20	/* Timer data read register */
#define RTC_TLR		0x24	/* Timer data load register */
#define RTC_TCR		0x28	/* Timer control register */
#define RTC_YDR		0x30	/* Year data read register */
#define RTC_YMR		0x34	/* Year match register */
#define RTC_YLR		0x38	/* Year data load register */

#define RTC_CR_EN	(1 << 0)	/* counter enable bit */
#define RTC_CR_CWEN	(1 << 26)	/* Clockwatch enable bit */

#define RTC_TCR_EN	(1 << 1) /* Periodic timer enable bit */

/* Common bit definitions for Interrupt status and control registers */
#define RTC_BIT_AI	(1 << 0) /* Alarm interrupt bit */
#define RTC_BIT_PI	(1 << 1) /* Periodic interrupt bit. ST variants only. */

/* Common bit definations for ST v2 for reading/writing time */
#define RTC_SEC_SHIFT 0
#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
#define RTC_MIN_SHIFT 6
#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
#define RTC_HOUR_SHIFT 12
#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
#define RTC_WDAY_SHIFT 17
#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
#define RTC_MDAY_SHIFT 20
#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
#define RTC_MON_SHIFT 25
#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */

#define RTC_TIMER_FREQ 32768

/**
 * struct pl031_vendor_data - per-vendor variations
 * @ops: the vendor-specific operations used on this silicon version
 * @clockwatch: if this is an ST Microelectronics silicon version with a
 *	clockwatch function
 * @st_weekday: if this is an ST Microelectronics silicon version that need
 *	the weekday fix
 * @irqflags: special IRQ flags per variant
 */
struct pl031_vendor_data {
	struct rtc_class_ops ops;
	bool clockwatch;
	bool st_weekday;
	unsigned long irqflags;
};

struct pl031_local {
	struct pl031_vendor_data *vendor;
	struct rtc_device *rtc;
	void __iomem *base;
};

static int pl031_alarm_irq_enable(struct device *dev,
	unsigned int enabled)
{
	struct pl031_local *ldata = dev_get_drvdata(dev);
	unsigned long imsc;

	/* Clear any pending alarm interrupts. */
	writel(RTC_BIT_AI, ldata->base + RTC_ICR);

	imsc = readl(ldata->base + RTC_IMSC);

	if (enabled == 1)
		writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
	else
		writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);

	return 0;
}

/*
 * Convert Gregorian date to ST v2 RTC format.
 */
static int pl031_stv2_tm_to_time(struct device *dev,
				 struct rtc_time *tm, unsigned long *st_time,
	unsigned long *bcd_year)
{
	int year = tm->tm_year + 1900;
	int wday = tm->tm_wday;

	/* wday masking is not working in hardware so wday must be valid */
	if (wday < -1 || wday > 6) {
		dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
		return -EINVAL;
	} else if (wday == -1) {
		/* wday is not provided, calculate it here */
		unsigned long time;
		struct rtc_time calc_tm;

		rtc_tm_to_time(tm, &time);
		rtc_time_to_tm(time, &calc_tm);
		wday = calc_tm.tm_wday;
	}

	*bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);

	*st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
			|	(tm->tm_mday << RTC_MDAY_SHIFT)
			|	((wday + 1) << RTC_WDAY_SHIFT)
			|	(tm->tm_hour << RTC_HOUR_SHIFT)
			|	(tm->tm_min << RTC_MIN_SHIFT)
			|	(tm->tm_sec << RTC_SEC_SHIFT);

	return 0;
}

/*
 * Convert ST v2 RTC format to Gregorian date.
 */
static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
	struct rtc_time *tm)
{
	tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
	tm->tm_mon  = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
	tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
	tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
	tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
	tm->tm_min  = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
	tm->tm_sec  = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);

	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
	tm->tm_year -= 1900;

	return 0;
}

static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
{
	struct pl031_local *ldata = dev_get_drvdata(dev);

	pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
			readl(ldata->base + RTC_YDR), tm);

	return 0;
}

static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
{
	unsigned long time;
	unsigned long bcd_year;
	struct pl031_local *ldata = dev_get_drvdata(dev);
	int ret;

	ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
	if (ret == 0) {
		writel(bcd_year, ldata->base + RTC_YLR);
		writel(time, ldata->base + RTC_LR);
	}

	return ret;
}

static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	struct pl031_local *ldata = dev_get_drvdata(dev);
	int ret;

	ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
			readl(ldata->base + RTC_YMR), &alarm->time);

	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;

	return ret;
}

static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	struct pl031_local *ldata = dev_get_drvdata(dev);
	unsigned long time;
	unsigned long bcd_year;
	int ret;

	/* At the moment, we can only deal with non-wildcarded alarm times. */
	ret = rtc_valid_tm(&alarm->time);
	if (ret == 0) {
		ret = pl031_stv2_tm_to_time(dev, &alarm->time,
					    &time, &bcd_year);
		if (ret == 0) {
			writel(bcd_year, ldata->base + RTC_YMR);
			writel(time, ldata->base + RTC_MR);

			pl031_alarm_irq_enable(dev, alarm->enabled);
		}
	}

	return ret;
}

static irqreturn_t pl031_interrupt(int irq, void *dev_id)
{
	struct pl031_local *ldata = dev_id;
	unsigned long rtcmis;
	unsigned long events = 0;

	rtcmis = readl(ldata->base + RTC_MIS);
	if (rtcmis & RTC_BIT_AI) {
		writel(RTC_BIT_AI, ldata->base + RTC_ICR);
		events |= (RTC_AF | RTC_IRQF);
		rtc_update_irq(ldata->rtc, 1, events);

		return IRQ_HANDLED;
	}

	return IRQ_NONE;
}

static int pl031_read_time(struct device *dev, struct rtc_time *tm)
{
	struct pl031_local *ldata = dev_get_drvdata(dev);

	rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);

	return 0;
}

static int pl031_set_time(struct device *dev, struct rtc_time *tm)
{
	unsigned long time;
	struct pl031_local *ldata = dev_get_drvdata(dev);
	int ret;

	ret = rtc_tm_to_time(tm, &time);

	if (ret == 0)
		writel(time, ldata->base + RTC_LR);

	return ret;
}

static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	struct pl031_local *ldata = dev_get_drvdata(dev);

	rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);

	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;

	return 0;
}

static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	struct pl031_local *ldata = dev_get_drvdata(dev);
	unsigned long time;
	int ret;

	/* At the moment, we can only deal with non-wildcarded alarm times. */
	ret = rtc_valid_tm(&alarm->time);
	if (ret == 0) {
		ret = rtc_tm_to_time(&alarm->time, &time);
		if (ret == 0) {
			writel(time, ldata->base + RTC_MR);
			pl031_alarm_irq_enable(dev, alarm->enabled);
		}
	}

	return ret;
}

static int pl031_remove(struct amba_device *adev)
{
	struct pl031_local *ldata = dev_get_drvdata(&adev->dev);

	dev_pm_clear_wake_irq(&adev->dev);
	device_init_wakeup(&adev->dev, false);
	if (adev->irq[0])
		free_irq(adev->irq[0], ldata);
	rtc_device_unregister(ldata->rtc);
	amba_release_regions(adev);

	return 0;
}

static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
{
	int ret;
	struct pl031_local *ldata;
	struct pl031_vendor_data *vendor = id->data;
	struct rtc_class_ops *ops;
	unsigned long time, data;

	ret = amba_request_regions(adev, NULL);
	if (ret)
		goto err_req;

	ldata = devm_kzalloc(&adev->dev, sizeof(struct pl031_local),
			     GFP_KERNEL);
	ops = devm_kmemdup(&adev->dev, &vendor->ops, sizeof(vendor->ops),
			   GFP_KERNEL);
	if (!ldata || !ops) {
		ret = -ENOMEM;
		goto out;
	}

	ldata->vendor = vendor;
	ldata->base = devm_ioremap(&adev->dev, adev->res.start,
				   resource_size(&adev->res));
	if (!ldata->base) {
		ret = -ENOMEM;
		goto out;
	}

	amba_set_drvdata(adev, ldata);

	dev_dbg(&adev->dev, "designer ID = 0x%02x\n", amba_manf(adev));
	dev_dbg(&adev->dev, "revision = 0x%01x\n", amba_rev(adev));

	data = readl(ldata->base + RTC_CR);
	/* Enable the clockwatch on ST Variants */
	if (vendor->clockwatch)
		data |= RTC_CR_CWEN;
	else
		data |= RTC_CR_EN;
	writel(data, ldata->base + RTC_CR);

	/*
	 * On ST PL031 variants, the RTC reset value does not provide correct
	 * weekday for 2000-01-01. Correct the erroneous sunday to saturday.
	 */
	if (vendor->st_weekday) {
		if (readl(ldata->base + RTC_YDR) == 0x2000) {
			time = readl(ldata->base + RTC_DR);
			if ((time &
			     (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK))
			    == 0x02120000) {
				time = time | (0x7 << RTC_WDAY_SHIFT);
				writel(0x2000, ldata->base + RTC_YLR);
				writel(time, ldata->base + RTC_LR);
			}
		}
	}

	if (!adev->irq[0]) {
		/* When there's no interrupt, no point in exposing the alarm */
		ops->read_alarm = NULL;
		ops->set_alarm = NULL;
		ops->alarm_irq_enable = NULL;
	}

	device_init_wakeup(&adev->dev, true);
	ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
					THIS_MODULE);
	if (IS_ERR(ldata->rtc)) {
		ret = PTR_ERR(ldata->rtc);
		goto out;
	}

	if (adev->irq[0]) {
		ret = request_irq(adev->irq[0], pl031_interrupt,
				  vendor->irqflags, "rtc-pl031", ldata);
		if (ret)
			goto out_no_irq;
		dev_pm_set_wake_irq(&adev->dev, adev->irq[0]);
	}
	return 0;

out_no_irq:
	rtc_device_unregister(ldata->rtc);
out:
	amba_release_regions(adev);
err_req:

	return ret;
}

/* Operations for the original ARM version */
static struct pl031_vendor_data arm_pl031 = {
	.ops = {
		.read_time = pl031_read_time,
		.set_time = pl031_set_time,
		.read_alarm = pl031_read_alarm,
		.set_alarm = pl031_set_alarm,
		.alarm_irq_enable = pl031_alarm_irq_enable,
	},
};

/* The First ST derivative */
static struct pl031_vendor_data stv1_pl031 = {
	.ops = {
		.read_time = pl031_read_time,
		.set_time = pl031_set_time,
		.read_alarm = pl031_read_alarm,
		.set_alarm = pl031_set_alarm,
		.alarm_irq_enable = pl031_alarm_irq_enable,
	},
	.clockwatch = true,
	.st_weekday = true,
};

/* And the second ST derivative */
static struct pl031_vendor_data stv2_pl031 = {
	.ops = {
		.read_time = pl031_stv2_read_time,
		.set_time = pl031_stv2_set_time,
		.read_alarm = pl031_stv2_read_alarm,
		.set_alarm = pl031_stv2_set_alarm,
		.alarm_irq_enable = pl031_alarm_irq_enable,
	},
	.clockwatch = true,
	.st_weekday = true,
	/*
	 * This variant shares the IRQ with another block and must not
	 * suspend that IRQ line.
	 * TODO check if it shares with IRQF_NO_SUSPEND user, else we can
	 * remove IRQF_COND_SUSPEND
	 */
	.irqflags = IRQF_SHARED | IRQF_COND_SUSPEND,
};

static const struct amba_id pl031_ids[] = {
	{
		.id = 0x00041031,
		.mask = 0x000fffff,
		.data = &arm_pl031,
	},
	/* ST Micro variants */
	{
		.id = 0x00180031,
		.mask = 0x00ffffff,
		.data = &stv1_pl031,
	},
	{
		.id = 0x00280031,
		.mask = 0x00ffffff,
		.data = &stv2_pl031,
	},
	{0, 0},
};

MODULE_DEVICE_TABLE(amba, pl031_ids);

static struct amba_driver pl031_driver = {
	.drv = {
		.name = "rtc-pl031",
	},
	.id_table = pl031_ids,
	.probe = pl031_probe,
	.remove = pl031_remove,
};

module_amba_driver(pl031_driver);

MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
8ae6e163 DS	1	/*
	2	* drivers/rtc/rtc-pl031.c
	3	*
	4	* Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
	5	*
	6	* Author: Deepak Saxena <dsaxena@plexity.net>
	7	*
	8	* Copyright 2006 (c) MontaVista Software, Inc.
	9	*
c72881e8 LW	10	* Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
	11	* Copyright 2010 (c) ST-Ericsson AB
	12	*
8ae6e163 DS	13	* This program is free software; you can redistribute it and/or
	14	* modify it under the terms of the GNU General Public License
	15	* as published by the Free Software Foundation; either version
	16	* 2 of the License, or (at your option) any later version.
	17	*/
8ae6e163 DS	18	#include <linux/module.h>
	19	#include <linux/rtc.h>
	20	#include <linux/init.h>
8ae6e163	21	#include <linux/interrupt.h>
8ae6e163	22	#include <linux/amba/bus.h>
2dba8518	23	#include <linux/io.h>
c72881e8 LW	24	#include <linux/bcd.h>
c72881e8 LW	25	#include <linux/delay.h>
eff6dd41	26	#include <linux/pm_wakeirq.h>
5a0e3ad6	27	#include <linux/slab.h>
8ae6e163 DS	28
	29	/*
	30	* Register definitions
	31	*/
	32	#define RTC_DR 0x00 /* Data read register */
	33	#define RTC_MR 0x04 /* Match register */
	34	#define RTC_LR 0x08 /* Data load register */
	35	#define RTC_CR 0x0c /* Control register */
	36	#define RTC_IMSC 0x10 /* Interrupt mask and set register */
	37	#define RTC_RIS 0x14 /* Raw interrupt status register */
	38	#define RTC_MIS 0x18 /* Masked interrupt status register */
	39	#define RTC_ICR 0x1c /* Interrupt clear register */
c72881e8 LW	40	/* ST variants have additional timer functionality */
	41	#define RTC_TDR 0x20 /* Timer data read register */
	42	#define RTC_TLR 0x24 /* Timer data load register */
	43	#define RTC_TCR 0x28 /* Timer control register */
	44	#define RTC_YDR 0x30 /* Year data read register */
	45	#define RTC_YMR 0x34 /* Year match register */
	46	#define RTC_YLR 0x38 /* Year data load register */
	47
e7e034e1	48	#define RTC_CR_EN (1 << 0) /* counter enable bit */
c72881e8 LW	49	#define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */
	50
	51	#define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
	52
	53	/* Common bit definitions for Interrupt status and control registers */
	54	#define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
	55	#define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
	56
	57	/* Common bit definations for ST v2 for reading/writing time */
	58	#define RTC_SEC_SHIFT 0
	59	#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
	60	#define RTC_MIN_SHIFT 6
	61	#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
	62	#define RTC_HOUR_SHIFT 12
	63	#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
	64	#define RTC_WDAY_SHIFT 17
	65	#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
	66	#define RTC_MDAY_SHIFT 20
	67	#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
	68	#define RTC_MON_SHIFT 25
	69	#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
	70
	71	#define RTC_TIMER_FREQ 32768
8ae6e163	72
aff05ed5 LW	73	/**
	74	* struct pl031_vendor_data - per-vendor variations
	75	* @ops: the vendor-specific operations used on this silicon version
1bb457fc LW	76	* @clockwatch: if this is an ST Microelectronics silicon version with a
	77	* clockwatch function
	78	* @st_weekday: if this is an ST Microelectronics silicon version that need
	79	* the weekday fix
559a6fc0	80	* @irqflags: special IRQ flags per variant
aff05ed5 LW	81	*/
	82	struct pl031_vendor_data {
	83	struct rtc_class_ops ops;
1bb457fc LW	84	bool clockwatch;
1bb457fc LW	85	bool st_weekday;
559a6fc0	86	unsigned long irqflags;
aff05ed5 LW	87	};
aff05ed5 LW	88
8ae6e163	89	struct pl031_local {
aff05ed5	90	struct pl031_vendor_data *vendor;
8ae6e163 DS	91	struct rtc_device *rtc;
	92	void __iomem *base;
	93	};
	94
c72881e8 LW	95	static int pl031_alarm_irq_enable(struct device *dev,
	96	unsigned int enabled)
	97	{
	98	struct pl031_local *ldata = dev_get_drvdata(dev);
	99	unsigned long imsc;
	100
	101	/* Clear any pending alarm interrupts. */
	102	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	103
	104	imsc = readl(ldata->base + RTC_IMSC);
	105
	106	if (enabled == 1)
	107	writel(imsc \| RTC_BIT_AI, ldata->base + RTC_IMSC);
	108	else
	109	writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
	110
	111	return 0;
	112	}
	113
	114	/*
	115	* Convert Gregorian date to ST v2 RTC format.
	116	*/
	117	static int pl031_stv2_tm_to_time(struct device *dev,
	118	struct rtc_time tm, unsigned long st_time,
	119	unsigned long *bcd_year)
	120	{
	121	int year = tm->tm_year + 1900;
	122	int wday = tm->tm_wday;
	123
	124	/* wday masking is not working in hardware so wday must be valid */
	125	if (wday < -1 \|\| wday > 6) {
	126	dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
	127	return -EINVAL;
	128	} else if (wday == -1) {
	129	/* wday is not provided, calculate it here */
	130	unsigned long time;
	131	struct rtc_time calc_tm;
	132
	133	rtc_tm_to_time(tm, &time);
	134	rtc_time_to_tm(time, &calc_tm);
	135	wday = calc_tm.tm_wday;
	136	}
	137
	138	*bcd_year = (bin2bcd(year % 100) \| bin2bcd(year / 100) << 8);
	139
	140	*st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
	141	\| (tm->tm_mday << RTC_MDAY_SHIFT)
	142	\| ((wday + 1) << RTC_WDAY_SHIFT)
	143	\| (tm->tm_hour << RTC_HOUR_SHIFT)
	144	\| (tm->tm_min << RTC_MIN_SHIFT)
	145	\| (tm->tm_sec << RTC_SEC_SHIFT);
	146
	147	return 0;
	148	}
	149
	150	/*
	151	* Convert ST v2 RTC format to Gregorian date.
	152	*/
	153	static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
	154	struct rtc_time *tm)
	155	{
	156	tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
	157	tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
	158	tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
159	tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
160	tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
161	tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
162	tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
163
164	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
165	tm->tm_year -= 1900;
166
167	return 0;
168	}
169
170	static int pl031_stv2_read_time(struct device dev, struct rtc_time tm)
171	{
172	struct pl031_local *ldata = dev_get_drvdata(dev);
173
174	pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
175	readl(ldata->base + RTC_YDR), tm);
176
177	return 0;
178	}
179
180	static int pl031_stv2_set_time(struct device dev, struct rtc_time tm)
181	{
182	unsigned long time;
183	unsigned long bcd_year;
184	struct pl031_local *ldata = dev_get_drvdata(dev);
185	int ret;
186
187	ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
188	if (ret == 0) {
189	writel(bcd_year, ldata->base + RTC_YLR);
190	writel(time, ldata->base + RTC_LR);
191	}
192
193	return ret;
194	}
195
196	static int pl031_stv2_read_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163	197	{
c72881e8 LW	198	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	199	int ret;
8ae6e163	200
c72881e8 LW	201	ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
c72881e8 LW	202	readl(ldata->base + RTC_YMR), &alarm->time);
8ae6e163	203
c72881e8 LW	204	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	205	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
	206
	207	return ret;
8ae6e163 DS	208	}
8ae6e163 DS	209
c72881e8	210	static int pl031_stv2_set_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163 DS	211	{
8ae6e163 DS	212	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	213	unsigned long time;
	214	unsigned long bcd_year;
	215	int ret;
	216
	217	/* At the moment, we can only deal with non-wildcarded alarm times. */
	218	ret = rtc_valid_tm(&alarm->time);
	219	if (ret == 0) {
	220	ret = pl031_stv2_tm_to_time(dev, &alarm->time,
	221	&time, &bcd_year);
	222	if (ret == 0) {
	223	writel(bcd_year, ldata->base + RTC_YMR);
	224	writel(time, ldata->base + RTC_MR);
	225
	226	pl031_alarm_irq_enable(dev, alarm->enabled);
	227	}
	228	}
	229
	230	return ret;
	231	}
	232
	233	static irqreturn_t pl031_interrupt(int irq, void *dev_id)
	234	{
	235	struct pl031_local *ldata = dev_id;
	236	unsigned long rtcmis;
	237	unsigned long events = 0;
	238
	239	rtcmis = readl(ldata->base + RTC_MIS);
ac2dee59 RK	240	if (rtcmis & RTC_BIT_AI) {
	241	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	242	events \|= (RTC_AF \| RTC_IRQF);
c72881e8	243	rtc_update_irq(ldata->rtc, 1, events);
8ae6e163	244
c72881e8	245	return IRQ_HANDLED;
8ae6e163 DS	246	}
8ae6e163 DS	247
c72881e8	248	return IRQ_NONE;
8ae6e163 DS	249	}
	250
	251	static int pl031_read_time(struct device dev, struct rtc_time tm)
	252	{
	253	struct pl031_local *ldata = dev_get_drvdata(dev);
	254
2934d6a8	255	rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
8ae6e163 DS	256
	257	return 0;
	258	}
	259
	260	static int pl031_set_time(struct device dev, struct rtc_time tm)
	261	{
	262	unsigned long time;
	263	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8	264	int ret;
8ae6e163	265
c72881e8	266	ret = rtc_tm_to_time(tm, &time);
8ae6e163	267
c72881e8 LW	268	if (ret == 0)
	269	writel(time, ldata->base + RTC_LR);
	270
	271	return ret;
8ae6e163 DS	272	}
	273
	274	static int pl031_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	275	{
	276	struct pl031_local *ldata = dev_get_drvdata(dev);
	277
2934d6a8	278	rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
c72881e8 LW	279
	280	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	281	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
8ae6e163 DS	282
	283	return 0;
	284	}
	285
	286	static int pl031_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	287	{
	288	struct pl031_local *ldata = dev_get_drvdata(dev);
	289	unsigned long time;
c72881e8 LW	290	int ret;
	291
	292	/* At the moment, we can only deal with non-wildcarded alarm times. */
	293	ret = rtc_valid_tm(&alarm->time);
	294	if (ret == 0) {
	295	ret = rtc_tm_to_time(&alarm->time, &time);
	296	if (ret == 0) {
	297	writel(time, ldata->base + RTC_MR);
	298	pl031_alarm_irq_enable(dev, alarm->enabled);
	299	}
	300	}
	301
	302	return ret;
	303	}
	304
8ae6e163 DS	305	static int pl031_remove(struct amba_device *adev)
	306	{
	307	struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
	308
eff6dd41 SH	309	dev_pm_clear_wake_irq(&adev->dev);
eff6dd41 SH	310	device_init_wakeup(&adev->dev, false);
5b64a296 RK	311	if (adev->irq[0])
5b64a296 RK	312	free_irq(adev->irq[0], ldata);
2dba8518	313	rtc_device_unregister(ldata->rtc);
2dba8518	314	amba_release_regions(adev);
8ae6e163 DS	315
	316	return 0;
	317	}
	318
aa25afad	319	static int pl031_probe(struct amba_device adev, const struct amba_id id)
8ae6e163 DS	320	{
	321	int ret;
	322	struct pl031_local *ldata;
aff05ed5	323	struct pl031_vendor_data *vendor = id->data;
b86f581f	324	struct rtc_class_ops *ops;
e7e034e1	325	unsigned long time, data;
8ae6e163	326
2dba8518 RK	327	ret = amba_request_regions(adev, NULL);
	328	if (ret)
	329	goto err_req;
8ae6e163	330
273c868e RK	331	ldata = devm_kzalloc(&adev->dev, sizeof(struct pl031_local),
273c868e RK	332	GFP_KERNEL);
b86f581f RK	333	ops = devm_kmemdup(&adev->dev, &vendor->ops, sizeof(vendor->ops),
	334	GFP_KERNEL);
	335	if (!ldata \|\| !ops) {
8ae6e163 DS	336	ret = -ENOMEM;
	337	goto out;
	338	}
8ae6e163	339
b86f581f	340	ldata->vendor = vendor;
273c868e RK	341	ldata->base = devm_ioremap(&adev->dev, adev->res.start,
273c868e RK	342	resource_size(&adev->res));
8ae6e163 DS	343	if (!ldata->base) {
8ae6e163 DS	344	ret = -ENOMEM;
273c868e	345	goto out;
8ae6e163 DS	346	}
8ae6e163 DS	347
2dba8518 RK	348	amba_set_drvdata(adev, ldata);
2dba8518 RK	349
1bb457fc LW	350	dev_dbg(&adev->dev, "designer ID = 0x%02x\n", amba_manf(adev));
1bb457fc LW	351	dev_dbg(&adev->dev, "revision = 0x%01x\n", amba_rev(adev));
8ae6e163	352
e7e034e1	353	data = readl(ldata->base + RTC_CR);
c72881e8	354	/* Enable the clockwatch on ST Variants */
1bb457fc	355	if (vendor->clockwatch)
e7e034e1	356	data \|= RTC_CR_CWEN;
3399cfb5 LW	357	else
	358	data \|= RTC_CR_EN;
	359	writel(data, ldata->base + RTC_CR);
c72881e8	360
c0a5f4a0 RK	361	/*
	362	* On ST PL031 variants, the RTC reset value does not provide correct
	363	* weekday for 2000-01-01. Correct the erroneous sunday to saturday.
	364	*/
1bb457fc	365	if (vendor->st_weekday) {
c0a5f4a0 RK	366	if (readl(ldata->base + RTC_YDR) == 0x2000) {
	367	time = readl(ldata->base + RTC_DR);
	368	if ((time &
	369	(RTC_MON_MASK \| RTC_MDAY_MASK \| RTC_WDAY_MASK))
	370	== 0x02120000) {
	371	time = time \| (0x7 << RTC_WDAY_SHIFT);
	372	writel(0x2000, ldata->base + RTC_YLR);
	373	writel(time, ldata->base + RTC_LR);
	374	}
	375	}
	376	}
	377
b86f581f RK	378	if (!adev->irq[0]) {
	379	/* When there's no interrupt, no point in exposing the alarm */
	380	ops->read_alarm = NULL;
	381	ops->set_alarm = NULL;
	382	ops->alarm_irq_enable = NULL;
	383	}
	384
eff6dd41	385	device_init_wakeup(&adev->dev, true);
c72881e8 LW	386	ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
c72881e8 LW	387	THIS_MODULE);
8ae6e163 DS	388	if (IS_ERR(ldata->rtc)) {
8ae6e163 DS	389	ret = PTR_ERR(ldata->rtc);
273c868e	390	goto out;
8ae6e163 DS	391	}
8ae6e163 DS	392
5b64a296 RK	393	if (adev->irq[0]) {
	394	ret = request_irq(adev->irq[0], pl031_interrupt,
	395	vendor->irqflags, "rtc-pl031", ldata);
	396	if (ret)
	397	goto out_no_irq;
	398	dev_pm_set_wake_irq(&adev->dev, adev->irq[0]);
c72881e8	399	}
8ae6e163 DS	400	return 0;
8ae6e163 DS	401
8ae6e163	402	out_no_irq:
c72881e8	403	rtc_device_unregister(ldata->rtc);
8ae6e163	404	out:
2dba8518 RK	405	amba_release_regions(adev);
2dba8518 RK	406	err_req:
c72881e8	407
8ae6e163 DS	408	return ret;
	409	}
	410
c72881e8	411	/* Operations for the original ARM version */
aff05ed5 LW	412	static struct pl031_vendor_data arm_pl031 = {
	413	.ops = {
	414	.read_time = pl031_read_time,
	415	.set_time = pl031_set_time,
	416	.read_alarm = pl031_read_alarm,
	417	.set_alarm = pl031_set_alarm,
	418	.alarm_irq_enable = pl031_alarm_irq_enable,
	419	},
c72881e8 LW	420	};
	421
	422	/* The First ST derivative */
aff05ed5 LW	423	static struct pl031_vendor_data stv1_pl031 = {
	424	.ops = {
	425	.read_time = pl031_read_time,
	426	.set_time = pl031_set_time,
	427	.read_alarm = pl031_read_alarm,
	428	.set_alarm = pl031_set_alarm,
	429	.alarm_irq_enable = pl031_alarm_irq_enable,
	430	},
1bb457fc LW	431	.clockwatch = true,
1bb457fc LW	432	.st_weekday = true,
c72881e8 LW	433	};
	434
	435	/* And the second ST derivative */
aff05ed5 LW	436	static struct pl031_vendor_data stv2_pl031 = {
	437	.ops = {
	438	.read_time = pl031_stv2_read_time,
	439	.set_time = pl031_stv2_set_time,
	440	.read_alarm = pl031_stv2_read_alarm,
	441	.set_alarm = pl031_stv2_set_alarm,
	442	.alarm_irq_enable = pl031_alarm_irq_enable,
	443	},
1bb457fc LW	444	.clockwatch = true,
1bb457fc LW	445	.st_weekday = true,
559a6fc0 MW	446	/*
	447	* This variant shares the IRQ with another block and must not
	448	* suspend that IRQ line.
eff6dd41 SH	449	* TODO check if it shares with IRQF_NO_SUSPEND user, else we can
eff6dd41 SH	450	* remove IRQF_COND_SUSPEND
559a6fc0	451	*/
eff6dd41	452	.irqflags = IRQF_SHARED \| IRQF_COND_SUSPEND,
c72881e8 LW	453	};
c72881e8 LW	454
eb508b36	455	static const struct amba_id pl031_ids[] = {
8ae6e163	456	{
2934d6a8 LW	457	.id = 0x00041031,
2934d6a8 LW	458	.mask = 0x000fffff,
aff05ed5	459	.data = &arm_pl031,
c72881e8 LW	460	},
	461	/* ST Micro variants */
	462	{
	463	.id = 0x00180031,
	464	.mask = 0x00ffffff,
aff05ed5	465	.data = &stv1_pl031,
c72881e8 LW	466	},
	467	{
	468	.id = 0x00280031,
	469	.mask = 0x00ffffff,
aff05ed5	470	.data = &stv2_pl031,
2934d6a8	471	},
8ae6e163 DS	472	{0, 0},
	473	};
	474
f5feac2a DM	475	MODULE_DEVICE_TABLE(amba, pl031_ids);
f5feac2a DM	476
8ae6e163 DS	477	static struct amba_driver pl031_driver = {
	478	.drv = {
	479	.name = "rtc-pl031",
	480	},
	481	.id_table = pl031_ids,
	482	.probe = pl031_probe,
	483	.remove = pl031_remove,
	484	};
	485
9e5ed094	486	module_amba_driver(pl031_driver);
8ae6e163	487
27675ef0	488	MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
8ae6e163 DS	489	MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
8ae6e163 DS	490	MODULE_LICENSE("GPL");