[linux-2.6-block.git] / drivers / rtc / rtc-pl031.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * 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
 */
#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);
	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 = devm_rtc_allocate_device(&adev->dev);
	if (IS_ERR(ldata->rtc))
		return PTR_ERR(ldata->rtc);

	ldata->rtc->ops = ops;

	ret = rtc_register_device(ldata->rtc);
	if (ret)
		goto out;

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

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
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
8ae6e163 DS	2	/*
	3	* drivers/rtc/rtc-pl031.c
	4	*
	5	* Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
	6	*
	7	* Author: Deepak Saxena <dsaxena@plexity.net>
	8	*
	9	* Copyright 2006 (c) MontaVista Software, Inc.
	10	*
c72881e8 LW	11	* Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
c72881e8 LW	12	* Copyright 2010 (c) ST-Ericsson AB
8ae6e163	13	*/
8ae6e163 DS	14	#include <linux/module.h>
	15	#include <linux/rtc.h>
	16	#include <linux/init.h>
8ae6e163	17	#include <linux/interrupt.h>
8ae6e163	18	#include <linux/amba/bus.h>
2dba8518	19	#include <linux/io.h>
c72881e8 LW	20	#include <linux/bcd.h>
c72881e8 LW	21	#include <linux/delay.h>
eff6dd41	22	#include <linux/pm_wakeirq.h>
5a0e3ad6	23	#include <linux/slab.h>
8ae6e163 DS	24
	25	/*
	26	* Register definitions
	27	*/
	28	#define RTC_DR 0x00 /* Data read register */
	29	#define RTC_MR 0x04 /* Match register */
	30	#define RTC_LR 0x08 /* Data load register */
	31	#define RTC_CR 0x0c /* Control register */
	32	#define RTC_IMSC 0x10 /* Interrupt mask and set register */
	33	#define RTC_RIS 0x14 /* Raw interrupt status register */
	34	#define RTC_MIS 0x18 /* Masked interrupt status register */
	35	#define RTC_ICR 0x1c /* Interrupt clear register */
c72881e8 LW	36	/* ST variants have additional timer functionality */
	37	#define RTC_TDR 0x20 /* Timer data read register */
	38	#define RTC_TLR 0x24 /* Timer data load register */
	39	#define RTC_TCR 0x28 /* Timer control register */
	40	#define RTC_YDR 0x30 /* Year data read register */
	41	#define RTC_YMR 0x34 /* Year match register */
	42	#define RTC_YLR 0x38 /* Year data load register */
	43
e7e034e1	44	#define RTC_CR_EN (1 << 0) /* counter enable bit */
c72881e8 LW	45	#define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */
	46
	47	#define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
	48
	49	/* Common bit definitions for Interrupt status and control registers */
	50	#define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
	51	#define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
	52
	53	/* Common bit definations for ST v2 for reading/writing time */
	54	#define RTC_SEC_SHIFT 0
	55	#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
	56	#define RTC_MIN_SHIFT 6
	57	#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
	58	#define RTC_HOUR_SHIFT 12
	59	#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
	60	#define RTC_WDAY_SHIFT 17
	61	#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
	62	#define RTC_MDAY_SHIFT 20
	63	#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
	64	#define RTC_MON_SHIFT 25
	65	#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
	66
	67	#define RTC_TIMER_FREQ 32768
8ae6e163	68
aff05ed5 LW	69	/**
	70	* struct pl031_vendor_data - per-vendor variations
	71	* @ops: the vendor-specific operations used on this silicon version
1bb457fc LW	72	* @clockwatch: if this is an ST Microelectronics silicon version with a
	73	* clockwatch function
	74	* @st_weekday: if this is an ST Microelectronics silicon version that need
	75	* the weekday fix
559a6fc0	76	* @irqflags: special IRQ flags per variant
aff05ed5 LW	77	*/
	78	struct pl031_vendor_data {
	79	struct rtc_class_ops ops;
1bb457fc LW	80	bool clockwatch;
1bb457fc LW	81	bool st_weekday;
559a6fc0	82	unsigned long irqflags;
aff05ed5 LW	83	};
aff05ed5 LW	84
8ae6e163	85	struct pl031_local {
aff05ed5	86	struct pl031_vendor_data *vendor;
8ae6e163 DS	87	struct rtc_device *rtc;
	88	void __iomem *base;
	89	};
	90
c72881e8 LW	91	static int pl031_alarm_irq_enable(struct device *dev,
	92	unsigned int enabled)
	93	{
	94	struct pl031_local *ldata = dev_get_drvdata(dev);
	95	unsigned long imsc;
	96
	97	/* Clear any pending alarm interrupts. */
	98	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	99
	100	imsc = readl(ldata->base + RTC_IMSC);
	101
	102	if (enabled == 1)
	103	writel(imsc \| RTC_BIT_AI, ldata->base + RTC_IMSC);
	104	else
	105	writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
	106
	107	return 0;
	108	}
	109
	110	/*
	111	* Convert Gregorian date to ST v2 RTC format.
	112	*/
	113	static int pl031_stv2_tm_to_time(struct device *dev,
	114	struct rtc_time tm, unsigned long st_time,
	115	unsigned long *bcd_year)
	116	{
	117	int year = tm->tm_year + 1900;
	118	int wday = tm->tm_wday;
	119
	120	/* wday masking is not working in hardware so wday must be valid */
	121	if (wday < -1 \|\| wday > 6) {
	122	dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
	123	return -EINVAL;
	124	} else if (wday == -1) {
	125	/* wday is not provided, calculate it here */
	126	unsigned long time;
	127	struct rtc_time calc_tm;
	128
	129	rtc_tm_to_time(tm, &time);
	130	rtc_time_to_tm(time, &calc_tm);
	131	wday = calc_tm.tm_wday;
	132	}
	133
	134	*bcd_year = (bin2bcd(year % 100) \| bin2bcd(year / 100) << 8);
	135
	136	*st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
	137	\| (tm->tm_mday << RTC_MDAY_SHIFT)
	138	\| ((wday + 1) << RTC_WDAY_SHIFT)
	139	\| (tm->tm_hour << RTC_HOUR_SHIFT)
	140	\| (tm->tm_min << RTC_MIN_SHIFT)
	141	\| (tm->tm_sec << RTC_SEC_SHIFT);
	142
	143	return 0;
	144	}
	145
	146	/*
	147	* Convert ST v2 RTC format to Gregorian date.
	148	*/
	149	static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
	150	struct rtc_time *tm)
	151	{
	152	tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
	153	tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
	154	tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
155	tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
156	tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
157	tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
158	tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
159
160	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
161	tm->tm_year -= 1900;
162
163	return 0;
164	}
165
166	static int pl031_stv2_read_time(struct device dev, struct rtc_time tm)
167	{
168	struct pl031_local *ldata = dev_get_drvdata(dev);
169
170	pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
171	readl(ldata->base + RTC_YDR), tm);
172
173	return 0;
174	}
175
176	static int pl031_stv2_set_time(struct device dev, struct rtc_time tm)
177	{
178	unsigned long time;
179	unsigned long bcd_year;
180	struct pl031_local *ldata = dev_get_drvdata(dev);
181	int ret;
182
183	ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
184	if (ret == 0) {
185	writel(bcd_year, ldata->base + RTC_YLR);
186	writel(time, ldata->base + RTC_LR);
187	}
188
189	return ret;
190	}
191
192	static int pl031_stv2_read_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163	193	{
c72881e8 LW	194	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	195	int ret;
8ae6e163	196
c72881e8 LW	197	ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
c72881e8 LW	198	readl(ldata->base + RTC_YMR), &alarm->time);
8ae6e163	199
c72881e8 LW	200	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	201	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
	202
	203	return ret;
8ae6e163 DS	204	}
8ae6e163 DS	205
c72881e8	206	static int pl031_stv2_set_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163 DS	207	{
8ae6e163 DS	208	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	209	unsigned long time;
	210	unsigned long bcd_year;
	211	int ret;
	212
	213	/* At the moment, we can only deal with non-wildcarded alarm times. */
	214	ret = rtc_valid_tm(&alarm->time);
	215	if (ret == 0) {
	216	ret = pl031_stv2_tm_to_time(dev, &alarm->time,
	217	&time, &bcd_year);
	218	if (ret == 0) {
	219	writel(bcd_year, ldata->base + RTC_YMR);
	220	writel(time, ldata->base + RTC_MR);
	221
	222	pl031_alarm_irq_enable(dev, alarm->enabled);
	223	}
	224	}
	225
	226	return ret;
	227	}
	228
	229	static irqreturn_t pl031_interrupt(int irq, void *dev_id)
	230	{
	231	struct pl031_local *ldata = dev_id;
	232	unsigned long rtcmis;
	233	unsigned long events = 0;
	234
	235	rtcmis = readl(ldata->base + RTC_MIS);
ac2dee59 RK	236	if (rtcmis & RTC_BIT_AI) {
	237	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	238	events \|= (RTC_AF \| RTC_IRQF);
c72881e8	239	rtc_update_irq(ldata->rtc, 1, events);
8ae6e163	240
c72881e8	241	return IRQ_HANDLED;
8ae6e163 DS	242	}
8ae6e163 DS	243
c72881e8	244	return IRQ_NONE;
8ae6e163 DS	245	}
	246
	247	static int pl031_read_time(struct device dev, struct rtc_time tm)
	248	{
	249	struct pl031_local *ldata = dev_get_drvdata(dev);
	250
2934d6a8	251	rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
8ae6e163 DS	252
	253	return 0;
	254	}
	255
	256	static int pl031_set_time(struct device dev, struct rtc_time tm)
	257	{
	258	unsigned long time;
	259	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8	260	int ret;
8ae6e163	261
c72881e8	262	ret = rtc_tm_to_time(tm, &time);
8ae6e163	263
c72881e8 LW	264	if (ret == 0)
	265	writel(time, ldata->base + RTC_LR);
	266
	267	return ret;
8ae6e163 DS	268	}
	269
	270	static int pl031_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	271	{
	272	struct pl031_local *ldata = dev_get_drvdata(dev);
	273
2934d6a8	274	rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
c72881e8 LW	275
	276	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	277	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
8ae6e163 DS	278
	279	return 0;
	280	}
	281
	282	static int pl031_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	283	{
	284	struct pl031_local *ldata = dev_get_drvdata(dev);
	285	unsigned long time;
c72881e8 LW	286	int ret;
	287
	288	/* At the moment, we can only deal with non-wildcarded alarm times. */
	289	ret = rtc_valid_tm(&alarm->time);
	290	if (ret == 0) {
	291	ret = rtc_tm_to_time(&alarm->time, &time);
	292	if (ret == 0) {
	293	writel(time, ldata->base + RTC_MR);
	294	pl031_alarm_irq_enable(dev, alarm->enabled);
	295	}
	296	}
	297
	298	return ret;
	299	}
	300
8ae6e163 DS	301	static int pl031_remove(struct amba_device *adev)
	302	{
	303	struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
	304
eff6dd41 SH	305	dev_pm_clear_wake_irq(&adev->dev);
eff6dd41 SH	306	device_init_wakeup(&adev->dev, false);
5b64a296 RK	307	if (adev->irq[0])
5b64a296 RK	308	free_irq(adev->irq[0], ldata);
2dba8518	309	amba_release_regions(adev);
8ae6e163 DS	310
	311	return 0;
	312	}
	313
aa25afad	314	static int pl031_probe(struct amba_device adev, const struct amba_id id)
8ae6e163 DS	315	{
	316	int ret;
	317	struct pl031_local *ldata;
aff05ed5	318	struct pl031_vendor_data *vendor = id->data;
b86f581f	319	struct rtc_class_ops *ops;
e7e034e1	320	unsigned long time, data;
8ae6e163	321
2dba8518 RK	322	ret = amba_request_regions(adev, NULL);
	323	if (ret)
	324	goto err_req;
8ae6e163	325
273c868e RK	326	ldata = devm_kzalloc(&adev->dev, sizeof(struct pl031_local),
273c868e RK	327	GFP_KERNEL);
b86f581f RK	328	ops = devm_kmemdup(&adev->dev, &vendor->ops, sizeof(vendor->ops),
	329	GFP_KERNEL);
	330	if (!ldata \|\| !ops) {
8ae6e163 DS	331	ret = -ENOMEM;
	332	goto out;
	333	}
8ae6e163	334
b86f581f	335	ldata->vendor = vendor;
273c868e RK	336	ldata->base = devm_ioremap(&adev->dev, adev->res.start,
273c868e RK	337	resource_size(&adev->res));
8ae6e163 DS	338	if (!ldata->base) {
8ae6e163 DS	339	ret = -ENOMEM;
273c868e	340	goto out;
8ae6e163 DS	341	}
8ae6e163 DS	342
2dba8518 RK	343	amba_set_drvdata(adev, ldata);
2dba8518 RK	344
1bb457fc LW	345	dev_dbg(&adev->dev, "designer ID = 0x%02x\n", amba_manf(adev));
1bb457fc LW	346	dev_dbg(&adev->dev, "revision = 0x%01x\n", amba_rev(adev));
8ae6e163	347
e7e034e1	348	data = readl(ldata->base + RTC_CR);
c72881e8	349	/* Enable the clockwatch on ST Variants */
1bb457fc	350	if (vendor->clockwatch)
e7e034e1	351	data \|= RTC_CR_CWEN;
3399cfb5 LW	352	else
	353	data \|= RTC_CR_EN;
	354	writel(data, ldata->base + RTC_CR);
c72881e8	355
c0a5f4a0 RK	356	/*
	357	* On ST PL031 variants, the RTC reset value does not provide correct
	358	* weekday for 2000-01-01. Correct the erroneous sunday to saturday.
	359	*/
1bb457fc	360	if (vendor->st_weekday) {
c0a5f4a0 RK	361	if (readl(ldata->base + RTC_YDR) == 0x2000) {
	362	time = readl(ldata->base + RTC_DR);
	363	if ((time &
	364	(RTC_MON_MASK \| RTC_MDAY_MASK \| RTC_WDAY_MASK))
	365	== 0x02120000) {
	366	time = time \| (0x7 << RTC_WDAY_SHIFT);
	367	writel(0x2000, ldata->base + RTC_YLR);
	368	writel(time, ldata->base + RTC_LR);
	369	}
	370	}
	371	}
	372
b86f581f RK	373	if (!adev->irq[0]) {
	374	/* When there's no interrupt, no point in exposing the alarm */
	375	ops->read_alarm = NULL;
	376	ops->set_alarm = NULL;
	377	ops->alarm_irq_enable = NULL;
	378	}
	379
eff6dd41	380	device_init_wakeup(&adev->dev, true);
b7aff107 AB	381	ldata->rtc = devm_rtc_allocate_device(&adev->dev);
	382	if (IS_ERR(ldata->rtc))
	383	return PTR_ERR(ldata->rtc);
	384
	385	ldata->rtc->ops = ops;
	386
	387	ret = rtc_register_device(ldata->rtc);
	388	if (ret)
273c868e	389	goto out;
8ae6e163	390
5b64a296 RK	391	if (adev->irq[0]) {
	392	ret = request_irq(adev->irq[0], pl031_interrupt,
	393	vendor->irqflags, "rtc-pl031", ldata);
	394	if (ret)
b7aff107	395	goto out;
5b64a296	396	dev_pm_set_wake_irq(&adev->dev, adev->irq[0]);
c72881e8	397	}
8ae6e163 DS	398	return 0;
8ae6e163 DS	399
8ae6e163	400	out:
2dba8518 RK	401	amba_release_regions(adev);
2dba8518 RK	402	err_req:
c72881e8	403
8ae6e163 DS	404	return ret;
	405	}
	406
c72881e8	407	/* Operations for the original ARM version */
aff05ed5 LW	408	static struct pl031_vendor_data arm_pl031 = {
	409	.ops = {
	410	.read_time = pl031_read_time,
	411	.set_time = pl031_set_time,
	412	.read_alarm = pl031_read_alarm,
	413	.set_alarm = pl031_set_alarm,
	414	.alarm_irq_enable = pl031_alarm_irq_enable,
	415	},
c72881e8 LW	416	};
	417
	418	/* The First ST derivative */
aff05ed5 LW	419	static struct pl031_vendor_data stv1_pl031 = {
	420	.ops = {
	421	.read_time = pl031_read_time,
	422	.set_time = pl031_set_time,
	423	.read_alarm = pl031_read_alarm,
	424	.set_alarm = pl031_set_alarm,
	425	.alarm_irq_enable = pl031_alarm_irq_enable,
	426	},
1bb457fc LW	427	.clockwatch = true,
1bb457fc LW	428	.st_weekday = true,
c72881e8 LW	429	};
	430
	431	/* And the second ST derivative */
aff05ed5 LW	432	static struct pl031_vendor_data stv2_pl031 = {
	433	.ops = {
	434	.read_time = pl031_stv2_read_time,
	435	.set_time = pl031_stv2_set_time,
	436	.read_alarm = pl031_stv2_read_alarm,
	437	.set_alarm = pl031_stv2_set_alarm,
	438	.alarm_irq_enable = pl031_alarm_irq_enable,
	439	},
1bb457fc LW	440	.clockwatch = true,
1bb457fc LW	441	.st_weekday = true,
559a6fc0 MW	442	/*
	443	* This variant shares the IRQ with another block and must not
	444	* suspend that IRQ line.
eff6dd41 SH	445	* TODO check if it shares with IRQF_NO_SUSPEND user, else we can
eff6dd41 SH	446	* remove IRQF_COND_SUSPEND
559a6fc0	447	*/
eff6dd41	448	.irqflags = IRQF_SHARED \| IRQF_COND_SUSPEND,
c72881e8 LW	449	};
c72881e8 LW	450
eb508b36	451	static const struct amba_id pl031_ids[] = {
8ae6e163	452	{
2934d6a8 LW	453	.id = 0x00041031,
2934d6a8 LW	454	.mask = 0x000fffff,
aff05ed5	455	.data = &arm_pl031,
c72881e8 LW	456	},
	457	/* ST Micro variants */
	458	{
	459	.id = 0x00180031,
	460	.mask = 0x00ffffff,
aff05ed5	461	.data = &stv1_pl031,
c72881e8 LW	462	},
	463	{
	464	.id = 0x00280031,
	465	.mask = 0x00ffffff,
aff05ed5	466	.data = &stv2_pl031,
2934d6a8	467	},
8ae6e163 DS	468	{0, 0},
	469	};
	470
f5feac2a DM	471	MODULE_DEVICE_TABLE(amba, pl031_ids);
f5feac2a DM	472
8ae6e163 DS	473	static struct amba_driver pl031_driver = {
	474	.drv = {
	475	.name = "rtc-pl031",
	476	},
	477	.id_table = pl031_ids,
	478	.probe = pl031_probe,
	479	.remove = pl031_remove,
	480	};
	481
9e5ed094	482	module_amba_driver(pl031_driver);
8ae6e163	483
27675ef0	484	MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
8ae6e163 DS	485	MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
8ae6e163 DS	486	MODULE_LICENSE("GPL");