[deliverable/linux.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/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_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_local {
	struct rtc_device *rtc;
	void __iomem *base;
	u8 hw_designer;
	u8 hw_revision:4;
};

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);

	amba_set_drvdata(adev, NULL);
	free_irq(adev->irq[0], ldata->rtc);
	rtc_device_unregister(ldata->rtc);
	iounmap(ldata->base);
	kfree(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 rtc_class_ops *ops = id->data;
	unsigned long time;

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

	ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL);
	if (!ldata) {
		ret = -ENOMEM;
		goto out;
	}

	ldata->base = ioremap(adev->res.start, resource_size(&adev->res));

	if (!ldata->base) {
		ret = -ENOMEM;
		goto out_no_remap;
	}

	amba_set_drvdata(adev, ldata);

	ldata->hw_designer = amba_manf(adev);
	ldata->hw_revision = amba_rev(adev);

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

	/* Enable the clockwatch on ST Variants */
	if (ldata->hw_designer == AMBA_VENDOR_ST)
		writel(readl(ldata->base + RTC_CR) | RTC_CR_CWEN,
		       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 (ldata->hw_designer == AMBA_VENDOR_ST) {
		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);
			}
		}
	}

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

	if (request_irq(adev->irq[0], pl031_interrupt,
			0, "rtc-pl031", ldata)) {
		ret = -EIO;
		goto out_no_irq;
	}

	return 0;

out_no_irq:
	rtc_device_unregister(ldata->rtc);
out_no_rtc:
	iounmap(ldata->base);
	amba_set_drvdata(adev, NULL);
out_no_remap:
	kfree(ldata);
out:
	amba_release_regions(adev);
err_req:

	return ret;
}

/* Operations for the original ARM version */
static struct rtc_class_ops 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 rtc_class_ops 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,
};

/* And the second ST derivative */
static struct rtc_class_ops 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,
};

static struct amba_id pl031_ids[] = {
	{
		.id = 0x00041031,
		.mask = 0x000fffff,
		.data = &arm_pl031_ops,
	},
	/* ST Micro variants */
	{
		.id = 0x00180031,
		.mask = 0x00ffffff,
		.data = &stv1_pl031_ops,
	},
	{
		.id = 0x00280031,
		.mask = 0x00ffffff,
		.data = &stv2_pl031_ops,
	},
	{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>
5a0e3ad6	26	#include <linux/slab.h>
8ae6e163 DS	27
	28	/*
	29	* Register definitions
	30	*/
	31	#define RTC_DR 0x00 /* Data read register */
	32	#define RTC_MR 0x04 /* Match register */
	33	#define RTC_LR 0x08 /* Data load register */
	34	#define RTC_CR 0x0c /* Control register */
	35	#define RTC_IMSC 0x10 /* Interrupt mask and set register */
	36	#define RTC_RIS 0x14 /* Raw interrupt status register */
	37	#define RTC_MIS 0x18 /* Masked interrupt status register */
	38	#define RTC_ICR 0x1c /* Interrupt clear register */
c72881e8 LW	39	/* ST variants have additional timer functionality */
	40	#define RTC_TDR 0x20 /* Timer data read register */
	41	#define RTC_TLR 0x24 /* Timer data load register */
	42	#define RTC_TCR 0x28 /* Timer control register */
	43	#define RTC_YDR 0x30 /* Year data read register */
	44	#define RTC_YMR 0x34 /* Year match register */
	45	#define RTC_YLR 0x38 /* Year data load register */
	46
	47	#define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */
	48
	49	#define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
	50
	51	/* Common bit definitions for Interrupt status and control registers */
	52	#define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
	53	#define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
	54
	55	/* Common bit definations for ST v2 for reading/writing time */
	56	#define RTC_SEC_SHIFT 0
	57	#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
	58	#define RTC_MIN_SHIFT 6
	59	#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
	60	#define RTC_HOUR_SHIFT 12
	61	#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
	62	#define RTC_WDAY_SHIFT 17
	63	#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
	64	#define RTC_MDAY_SHIFT 20
	65	#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
	66	#define RTC_MON_SHIFT 25
	67	#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
	68
	69	#define RTC_TIMER_FREQ 32768
8ae6e163 DS	70
	71	struct pl031_local {
	72	struct rtc_device *rtc;
	73	void __iomem *base;
c72881e8 LW	74	u8 hw_designer;
c72881e8 LW	75	u8 hw_revision:4;
8ae6e163 DS	76	};
8ae6e163 DS	77
c72881e8 LW	78	static int pl031_alarm_irq_enable(struct device *dev,
	79	unsigned int enabled)
	80	{
	81	struct pl031_local *ldata = dev_get_drvdata(dev);
	82	unsigned long imsc;
	83
	84	/* Clear any pending alarm interrupts. */
	85	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	86
	87	imsc = readl(ldata->base + RTC_IMSC);
	88
	89	if (enabled == 1)
	90	writel(imsc \| RTC_BIT_AI, ldata->base + RTC_IMSC);
	91	else
	92	writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
	93
	94	return 0;
	95	}
	96
	97	/*
	98	* Convert Gregorian date to ST v2 RTC format.
	99	*/
	100	static int pl031_stv2_tm_to_time(struct device *dev,
	101	struct rtc_time tm, unsigned long st_time,
	102	unsigned long *bcd_year)
	103	{
	104	int year = tm->tm_year + 1900;
	105	int wday = tm->tm_wday;
	106
	107	/* wday masking is not working in hardware so wday must be valid */
	108	if (wday < -1 \|\| wday > 6) {
	109	dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
	110	return -EINVAL;
	111	} else if (wday == -1) {
	112	/* wday is not provided, calculate it here */
	113	unsigned long time;
	114	struct rtc_time calc_tm;
	115
	116	rtc_tm_to_time(tm, &time);
	117	rtc_time_to_tm(time, &calc_tm);
	118	wday = calc_tm.tm_wday;
	119	}
	120
	121	*bcd_year = (bin2bcd(year % 100) \| bin2bcd(year / 100) << 8);
	122
	123	*st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
	124	\| (tm->tm_mday << RTC_MDAY_SHIFT)
	125	\| ((wday + 1) << RTC_WDAY_SHIFT)
	126	\| (tm->tm_hour << RTC_HOUR_SHIFT)
	127	\| (tm->tm_min << RTC_MIN_SHIFT)
	128	\| (tm->tm_sec << RTC_SEC_SHIFT);
	129
	130	return 0;
	131	}
	132
	133	/*
	134	* Convert ST v2 RTC format to Gregorian date.
	135	*/
	136	static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
	137	struct rtc_time *tm)
	138	{
	139	tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
	140	tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
	141	tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
142	tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
143	tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
144	tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
145	tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
146
147	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
148	tm->tm_year -= 1900;
149
150	return 0;
151	}
152
153	static int pl031_stv2_read_time(struct device dev, struct rtc_time tm)
154	{
155	struct pl031_local *ldata = dev_get_drvdata(dev);
156
157	pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
158	readl(ldata->base + RTC_YDR), tm);
159
160	return 0;
161	}
162
163	static int pl031_stv2_set_time(struct device dev, struct rtc_time tm)
164	{
165	unsigned long time;
166	unsigned long bcd_year;
167	struct pl031_local *ldata = dev_get_drvdata(dev);
168	int ret;
169
170	ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
171	if (ret == 0) {
172	writel(bcd_year, ldata->base + RTC_YLR);
173	writel(time, ldata->base + RTC_LR);
174	}
175
176	return ret;
177	}
178
179	static int pl031_stv2_read_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163	180	{
c72881e8 LW	181	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	182	int ret;
8ae6e163	183
c72881e8 LW	184	ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
c72881e8 LW	185	readl(ldata->base + RTC_YMR), &alarm->time);
8ae6e163	186
c72881e8 LW	187	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	188	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
	189
	190	return ret;
8ae6e163 DS	191	}
8ae6e163 DS	192
c72881e8	193	static int pl031_stv2_set_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163 DS	194	{
8ae6e163 DS	195	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	196	unsigned long time;
	197	unsigned long bcd_year;
	198	int ret;
	199
	200	/* At the moment, we can only deal with non-wildcarded alarm times. */
	201	ret = rtc_valid_tm(&alarm->time);
	202	if (ret == 0) {
	203	ret = pl031_stv2_tm_to_time(dev, &alarm->time,
	204	&time, &bcd_year);
	205	if (ret == 0) {
	206	writel(bcd_year, ldata->base + RTC_YMR);
	207	writel(time, ldata->base + RTC_MR);
	208
	209	pl031_alarm_irq_enable(dev, alarm->enabled);
	210	}
	211	}
	212
	213	return ret;
	214	}
	215
	216	static irqreturn_t pl031_interrupt(int irq, void *dev_id)
	217	{
	218	struct pl031_local *ldata = dev_id;
	219	unsigned long rtcmis;
	220	unsigned long events = 0;
	221
	222	rtcmis = readl(ldata->base + RTC_MIS);
ac2dee59 RK	223	if (rtcmis & RTC_BIT_AI) {
	224	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	225	events \|= (RTC_AF \| RTC_IRQF);
c72881e8	226	rtc_update_irq(ldata->rtc, 1, events);
8ae6e163	227
c72881e8	228	return IRQ_HANDLED;
8ae6e163 DS	229	}
8ae6e163 DS	230
c72881e8	231	return IRQ_NONE;
8ae6e163 DS	232	}
	233
	234	static int pl031_read_time(struct device dev, struct rtc_time tm)
	235	{
	236	struct pl031_local *ldata = dev_get_drvdata(dev);
	237
2934d6a8	238	rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
8ae6e163 DS	239
	240	return 0;
	241	}
	242
	243	static int pl031_set_time(struct device dev, struct rtc_time tm)
	244	{
	245	unsigned long time;
	246	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8	247	int ret;
8ae6e163	248
c72881e8	249	ret = rtc_tm_to_time(tm, &time);
8ae6e163	250
c72881e8 LW	251	if (ret == 0)
	252	writel(time, ldata->base + RTC_LR);
	253
	254	return ret;
8ae6e163 DS	255	}
	256
	257	static int pl031_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	258	{
	259	struct pl031_local *ldata = dev_get_drvdata(dev);
	260
2934d6a8	261	rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
c72881e8 LW	262
	263	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	264	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
8ae6e163 DS	265
	266	return 0;
	267	}
	268
	269	static int pl031_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	270	{
	271	struct pl031_local *ldata = dev_get_drvdata(dev);
	272	unsigned long time;
c72881e8 LW	273	int ret;
	274
	275	/* At the moment, we can only deal with non-wildcarded alarm times. */
	276	ret = rtc_valid_tm(&alarm->time);
	277	if (ret == 0) {
	278	ret = rtc_tm_to_time(&alarm->time, &time);
	279	if (ret == 0) {
	280	writel(time, ldata->base + RTC_MR);
	281	pl031_alarm_irq_enable(dev, alarm->enabled);
	282	}
	283	}
	284
	285	return ret;
	286	}
	287
8ae6e163 DS	288	static int pl031_remove(struct amba_device *adev)
	289	{
	290	struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
	291
2dba8518 RK	292	amba_set_drvdata(adev, NULL);
	293	free_irq(adev->irq[0], ldata->rtc);
	294	rtc_device_unregister(ldata->rtc);
	295	iounmap(ldata->base);
	296	kfree(ldata);
	297	amba_release_regions(adev);
8ae6e163 DS	298
	299	return 0;
	300	}
	301
aa25afad	302	static int pl031_probe(struct amba_device adev, const struct amba_id id)
8ae6e163 DS	303	{
	304	int ret;
	305	struct pl031_local *ldata;
c72881e8	306	struct rtc_class_ops *ops = id->data;
c0a5f4a0	307	unsigned long time;
8ae6e163	308
2dba8518 RK	309	ret = amba_request_regions(adev, NULL);
	310	if (ret)
	311	goto err_req;
8ae6e163	312
c72881e8	313	ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL);
8ae6e163 DS	314	if (!ldata) {
	315	ret = -ENOMEM;
	316	goto out;
	317	}
8ae6e163	318
dc890c2d	319	ldata->base = ioremap(adev->res.start, resource_size(&adev->res));
c72881e8	320
8ae6e163 DS	321	if (!ldata->base) {
	322	ret = -ENOMEM;
	323	goto out_no_remap;
	324	}
	325
2dba8518 RK	326	amba_set_drvdata(adev, ldata);
2dba8518 RK	327
c72881e8 LW	328	ldata->hw_designer = amba_manf(adev);
	329	ldata->hw_revision = amba_rev(adev);
	330
	331	dev_dbg(&adev->dev, "designer ID = 0x%02x\n", ldata->hw_designer);
	332	dev_dbg(&adev->dev, "revision = 0x%01x\n", ldata->hw_revision);
8ae6e163	333
c72881e8	334	/* Enable the clockwatch on ST Variants */
2f397216	335	if (ldata->hw_designer == AMBA_VENDOR_ST)
c72881e8 LW	336	writel(readl(ldata->base + RTC_CR) \| RTC_CR_CWEN,
	337	ldata->base + RTC_CR);
	338
c0a5f4a0 RK	339	/*
	340	* On ST PL031 variants, the RTC reset value does not provide correct
	341	* weekday for 2000-01-01. Correct the erroneous sunday to saturday.
	342	*/
	343	if (ldata->hw_designer == AMBA_VENDOR_ST) {
	344	if (readl(ldata->base + RTC_YDR) == 0x2000) {
	345	time = readl(ldata->base + RTC_DR);
	346	if ((time &
	347	(RTC_MON_MASK \| RTC_MDAY_MASK \| RTC_WDAY_MASK))
	348	== 0x02120000) {
	349	time = time \| (0x7 << RTC_WDAY_SHIFT);
	350	writel(0x2000, ldata->base + RTC_YLR);
	351	writel(time, ldata->base + RTC_LR);
	352	}
	353	}
	354	}
	355
c72881e8 LW	356	ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
c72881e8 LW	357	THIS_MODULE);
8ae6e163 DS	358	if (IS_ERR(ldata->rtc)) {
	359	ret = PTR_ERR(ldata->rtc);
	360	goto out_no_rtc;
	361	}
	362
c72881e8	363	if (request_irq(adev->irq[0], pl031_interrupt,
2f6e5f94	364	0, "rtc-pl031", ldata)) {
c72881e8 LW	365	ret = -EIO;
	366	goto out_no_irq;
	367	}
	368
8ae6e163 DS	369	return 0;
8ae6e163 DS	370
8ae6e163	371	out_no_irq:
c72881e8 LW	372	rtc_device_unregister(ldata->rtc);
c72881e8 LW	373	out_no_rtc:
8ae6e163	374	iounmap(ldata->base);
2dba8518	375	amba_set_drvdata(adev, NULL);
8ae6e163	376	out_no_remap:
8ae6e163 DS	377	kfree(ldata);
8ae6e163 DS	378	out:
2dba8518 RK	379	amba_release_regions(adev);
2dba8518 RK	380	err_req:
c72881e8	381
8ae6e163 DS	382	return ret;
	383	}
	384
c72881e8 LW	385	/* Operations for the original ARM version */
	386	static struct rtc_class_ops arm_pl031_ops = {
	387	.read_time = pl031_read_time,
	388	.set_time = pl031_set_time,
	389	.read_alarm = pl031_read_alarm,
	390	.set_alarm = pl031_set_alarm,
	391	.alarm_irq_enable = pl031_alarm_irq_enable,
	392	};
	393
	394	/* The First ST derivative */
	395	static struct rtc_class_ops stv1_pl031_ops = {
	396	.read_time = pl031_read_time,
	397	.set_time = pl031_set_time,
	398	.read_alarm = pl031_read_alarm,
	399	.set_alarm = pl031_set_alarm,
	400	.alarm_irq_enable = pl031_alarm_irq_enable,
c72881e8 LW	401	};
	402
	403	/* And the second ST derivative */
	404	static struct rtc_class_ops stv2_pl031_ops = {
	405	.read_time = pl031_stv2_read_time,
	406	.set_time = pl031_stv2_set_time,
	407	.read_alarm = pl031_stv2_read_alarm,
	408	.set_alarm = pl031_stv2_set_alarm,
	409	.alarm_irq_enable = pl031_alarm_irq_enable,
c72881e8 LW	410	};
c72881e8 LW	411
2c39c9e1	412	static struct amba_id pl031_ids[] = {
8ae6e163	413	{
2934d6a8 LW	414	.id = 0x00041031,
2934d6a8 LW	415	.mask = 0x000fffff,
c72881e8 LW	416	.data = &arm_pl031_ops,
	417	},
	418	/* ST Micro variants */
	419	{
	420	.id = 0x00180031,
	421	.mask = 0x00ffffff,
	422	.data = &stv1_pl031_ops,
	423	},
	424	{
	425	.id = 0x00280031,
	426	.mask = 0x00ffffff,
	427	.data = &stv2_pl031_ops,
2934d6a8	428	},
8ae6e163 DS	429	{0, 0},
	430	};
	431
f5feac2a DM	432	MODULE_DEVICE_TABLE(amba, pl031_ids);
f5feac2a DM	433
8ae6e163 DS	434	static struct amba_driver pl031_driver = {
	435	.drv = {
	436	.name = "rtc-pl031",
	437	},
	438	.id_table = pl031_ids,
	439	.probe = pl031_probe,
	440	.remove = pl031_remove,
	441	};
	442
9e5ed094	443	module_amba_driver(pl031_driver);
8ae6e163 DS	444
	445	MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net");
	446	MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
	447	MODULE_LICENSE("GPL");