[mirror_ubuntu-zesty-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/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_vendor_data - per-vendor variations
 * @ops: the vendor-specific operations used on this silicon version
 */
struct pl031_vendor_data {
	struct rtc_class_ops ops;
};

struct pl031_local {
	struct pl031_vendor_data *vendor;
	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 pl031_vendor_data *vendor = id->data;
	struct rtc_class_ops *ops = &vendor->ops;
	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->vendor = vendor;

	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 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,
	},
};

/* 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,
	},
};

static 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>
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	70
aff05ed5 LW	71	/**
	72	* struct pl031_vendor_data - per-vendor variations
	73	* @ops: the vendor-specific operations used on this silicon version
	74	*/
	75	struct pl031_vendor_data {
	76	struct rtc_class_ops ops;
	77	};
	78
8ae6e163	79	struct pl031_local {
aff05ed5	80	struct pl031_vendor_data *vendor;
8ae6e163 DS	81	struct rtc_device *rtc;
8ae6e163 DS	82	void __iomem *base;
c72881e8 LW	83	u8 hw_designer;
c72881e8 LW	84	u8 hw_revision:4;
8ae6e163 DS	85	};
8ae6e163 DS	86
c72881e8 LW	87	static int pl031_alarm_irq_enable(struct device *dev,
	88	unsigned int enabled)
	89	{
	90	struct pl031_local *ldata = dev_get_drvdata(dev);
	91	unsigned long imsc;
	92
	93	/* Clear any pending alarm interrupts. */
	94	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	95
	96	imsc = readl(ldata->base + RTC_IMSC);
	97
	98	if (enabled == 1)
	99	writel(imsc \| RTC_BIT_AI, ldata->base + RTC_IMSC);
	100	else
	101	writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
	102
	103	return 0;
	104	}
	105
	106	/*
	107	* Convert Gregorian date to ST v2 RTC format.
	108	*/
	109	static int pl031_stv2_tm_to_time(struct device *dev,
	110	struct rtc_time tm, unsigned long st_time,
	111	unsigned long *bcd_year)
	112	{
	113	int year = tm->tm_year + 1900;
	114	int wday = tm->tm_wday;
	115
	116	/* wday masking is not working in hardware so wday must be valid */
	117	if (wday < -1 \|\| wday > 6) {
	118	dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
	119	return -EINVAL;
	120	} else if (wday == -1) {
	121	/* wday is not provided, calculate it here */
	122	unsigned long time;
	123	struct rtc_time calc_tm;
	124
	125	rtc_tm_to_time(tm, &time);
	126	rtc_time_to_tm(time, &calc_tm);
	127	wday = calc_tm.tm_wday;
	128	}
	129
	130	*bcd_year = (bin2bcd(year % 100) \| bin2bcd(year / 100) << 8);
	131
	132	*st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
	133	\| (tm->tm_mday << RTC_MDAY_SHIFT)
	134	\| ((wday + 1) << RTC_WDAY_SHIFT)
	135	\| (tm->tm_hour << RTC_HOUR_SHIFT)
	136	\| (tm->tm_min << RTC_MIN_SHIFT)
	137	\| (tm->tm_sec << RTC_SEC_SHIFT);
	138
	139	return 0;
	140	}
	141
	142	/*
	143	* Convert ST v2 RTC format to Gregorian date.
	144	*/
	145	static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
	146	struct rtc_time *tm)
	147	{
	148	tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
	149	tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
	150	tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
151	tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
152	tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
153	tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
154	tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
155
156	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
157	tm->tm_year -= 1900;
158
159	return 0;
160	}
161
162	static int pl031_stv2_read_time(struct device dev, struct rtc_time tm)
163	{
164	struct pl031_local *ldata = dev_get_drvdata(dev);
165
166	pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
167	readl(ldata->base + RTC_YDR), tm);
168
169	return 0;
170	}
171
172	static int pl031_stv2_set_time(struct device dev, struct rtc_time tm)
173	{
174	unsigned long time;
175	unsigned long bcd_year;
176	struct pl031_local *ldata = dev_get_drvdata(dev);
177	int ret;
178
179	ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
180	if (ret == 0) {
181	writel(bcd_year, ldata->base + RTC_YLR);
182	writel(time, ldata->base + RTC_LR);
183	}
184
185	return ret;
186	}
187
188	static int pl031_stv2_read_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163	189	{
c72881e8 LW	190	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	191	int ret;
8ae6e163	192
c72881e8 LW	193	ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
c72881e8 LW	194	readl(ldata->base + RTC_YMR), &alarm->time);
8ae6e163	195
c72881e8 LW	196	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	197	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
	198
	199	return ret;
8ae6e163 DS	200	}
8ae6e163 DS	201
c72881e8	202	static int pl031_stv2_set_alarm(struct device dev, struct rtc_wkalrm alarm)
8ae6e163 DS	203	{
8ae6e163 DS	204	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8 LW	205	unsigned long time;
	206	unsigned long bcd_year;
	207	int ret;
	208
	209	/* At the moment, we can only deal with non-wildcarded alarm times. */
	210	ret = rtc_valid_tm(&alarm->time);
	211	if (ret == 0) {
	212	ret = pl031_stv2_tm_to_time(dev, &alarm->time,
	213	&time, &bcd_year);
	214	if (ret == 0) {
	215	writel(bcd_year, ldata->base + RTC_YMR);
	216	writel(time, ldata->base + RTC_MR);
	217
	218	pl031_alarm_irq_enable(dev, alarm->enabled);
	219	}
	220	}
	221
	222	return ret;
	223	}
	224
	225	static irqreturn_t pl031_interrupt(int irq, void *dev_id)
	226	{
	227	struct pl031_local *ldata = dev_id;
	228	unsigned long rtcmis;
	229	unsigned long events = 0;
	230
	231	rtcmis = readl(ldata->base + RTC_MIS);
ac2dee59 RK	232	if (rtcmis & RTC_BIT_AI) {
	233	writel(RTC_BIT_AI, ldata->base + RTC_ICR);
	234	events \|= (RTC_AF \| RTC_IRQF);
c72881e8	235	rtc_update_irq(ldata->rtc, 1, events);
8ae6e163	236
c72881e8	237	return IRQ_HANDLED;
8ae6e163 DS	238	}
8ae6e163 DS	239
c72881e8	240	return IRQ_NONE;
8ae6e163 DS	241	}
	242
	243	static int pl031_read_time(struct device dev, struct rtc_time tm)
	244	{
	245	struct pl031_local *ldata = dev_get_drvdata(dev);
	246
2934d6a8	247	rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
8ae6e163 DS	248
	249	return 0;
	250	}
	251
	252	static int pl031_set_time(struct device dev, struct rtc_time tm)
	253	{
	254	unsigned long time;
	255	struct pl031_local *ldata = dev_get_drvdata(dev);
c72881e8	256	int ret;
8ae6e163	257
c72881e8	258	ret = rtc_tm_to_time(tm, &time);
8ae6e163	259
c72881e8 LW	260	if (ret == 0)
	261	writel(time, ldata->base + RTC_LR);
	262
	263	return ret;
8ae6e163 DS	264	}
	265
	266	static int pl031_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	267	{
	268	struct pl031_local *ldata = dev_get_drvdata(dev);
	269
2934d6a8	270	rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
c72881e8 LW	271
	272	alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
	273	alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
8ae6e163 DS	274
	275	return 0;
	276	}
	277
	278	static int pl031_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	279	{
	280	struct pl031_local *ldata = dev_get_drvdata(dev);
	281	unsigned long time;
c72881e8 LW	282	int ret;
	283
	284	/* At the moment, we can only deal with non-wildcarded alarm times. */
	285	ret = rtc_valid_tm(&alarm->time);
	286	if (ret == 0) {
	287	ret = rtc_tm_to_time(&alarm->time, &time);
	288	if (ret == 0) {
	289	writel(time, ldata->base + RTC_MR);
	290	pl031_alarm_irq_enable(dev, alarm->enabled);
	291	}
	292	}
	293
	294	return ret;
	295	}
	296
8ae6e163 DS	297	static int pl031_remove(struct amba_device *adev)
	298	{
	299	struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
	300
2dba8518 RK	301	amba_set_drvdata(adev, NULL);
	302	free_irq(adev->irq[0], ldata->rtc);
	303	rtc_device_unregister(ldata->rtc);
	304	iounmap(ldata->base);
	305	kfree(ldata);
	306	amba_release_regions(adev);
8ae6e163 DS	307
	308	return 0;
	309	}
	310
aa25afad	311	static int pl031_probe(struct amba_device adev, const struct amba_id id)
8ae6e163 DS	312	{
	313	int ret;
	314	struct pl031_local *ldata;
aff05ed5 LW	315	struct pl031_vendor_data *vendor = id->data;
aff05ed5 LW	316	struct rtc_class_ops *ops = &vendor->ops;
c0a5f4a0	317	unsigned long time;
8ae6e163	318
2dba8518 RK	319	ret = amba_request_regions(adev, NULL);
	320	if (ret)
	321	goto err_req;
8ae6e163	322
c72881e8	323	ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL);
8ae6e163 DS	324	if (!ldata) {
	325	ret = -ENOMEM;
	326	goto out;
	327	}
aff05ed5	328	ldata->vendor = vendor;
8ae6e163	329
dc890c2d	330	ldata->base = ioremap(adev->res.start, resource_size(&adev->res));
c72881e8	331
8ae6e163 DS	332	if (!ldata->base) {
	333	ret = -ENOMEM;
	334	goto out_no_remap;
	335	}
	336
2dba8518 RK	337	amba_set_drvdata(adev, ldata);
2dba8518 RK	338
c72881e8 LW	339	ldata->hw_designer = amba_manf(adev);
	340	ldata->hw_revision = amba_rev(adev);
	341
	342	dev_dbg(&adev->dev, "designer ID = 0x%02x\n", ldata->hw_designer);
	343	dev_dbg(&adev->dev, "revision = 0x%01x\n", ldata->hw_revision);
8ae6e163	344
c72881e8	345	/* Enable the clockwatch on ST Variants */
2f397216	346	if (ldata->hw_designer == AMBA_VENDOR_ST)
c72881e8 LW	347	writel(readl(ldata->base + RTC_CR) \| RTC_CR_CWEN,
	348	ldata->base + RTC_CR);
	349
c0a5f4a0 RK	350	/*
	351	* On ST PL031 variants, the RTC reset value does not provide correct
	352	* weekday for 2000-01-01. Correct the erroneous sunday to saturday.
	353	*/
	354	if (ldata->hw_designer == AMBA_VENDOR_ST) {
	355	if (readl(ldata->base + RTC_YDR) == 0x2000) {
	356	time = readl(ldata->base + RTC_DR);
	357	if ((time &
	358	(RTC_MON_MASK \| RTC_MDAY_MASK \| RTC_WDAY_MASK))
	359	== 0x02120000) {
	360	time = time \| (0x7 << RTC_WDAY_SHIFT);
	361	writel(0x2000, ldata->base + RTC_YLR);
	362	writel(time, ldata->base + RTC_LR);
	363	}
	364	}
	365	}
	366
c72881e8 LW	367	ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
c72881e8 LW	368	THIS_MODULE);
8ae6e163 DS	369	if (IS_ERR(ldata->rtc)) {
	370	ret = PTR_ERR(ldata->rtc);
	371	goto out_no_rtc;
	372	}
	373
c72881e8	374	if (request_irq(adev->irq[0], pl031_interrupt,
2f6e5f94	375	0, "rtc-pl031", ldata)) {
c72881e8 LW	376	ret = -EIO;
	377	goto out_no_irq;
	378	}
	379
8ae6e163 DS	380	return 0;
8ae6e163 DS	381
8ae6e163	382	out_no_irq:
c72881e8 LW	383	rtc_device_unregister(ldata->rtc);
c72881e8 LW	384	out_no_rtc:
8ae6e163	385	iounmap(ldata->base);
2dba8518	386	amba_set_drvdata(adev, NULL);
8ae6e163	387	out_no_remap:
8ae6e163 DS	388	kfree(ldata);
8ae6e163 DS	389	out:
2dba8518 RK	390	amba_release_regions(adev);
2dba8518 RK	391	err_req:
c72881e8	392
8ae6e163 DS	393	return ret;
	394	}
	395
c72881e8	396	/* Operations for the original ARM version */
aff05ed5 LW	397	static struct pl031_vendor_data arm_pl031 = {
	398	.ops = {
	399	.read_time = pl031_read_time,
	400	.set_time = pl031_set_time,
	401	.read_alarm = pl031_read_alarm,
	402	.set_alarm = pl031_set_alarm,
	403	.alarm_irq_enable = pl031_alarm_irq_enable,
	404	},
c72881e8 LW	405	};
	406
	407	/* The First ST derivative */
aff05ed5 LW	408	static struct pl031_vendor_data stv1_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	/* And the second ST derivative */
aff05ed5 LW	419	static struct pl031_vendor_data stv2_pl031 = {
	420	.ops = {
	421	.read_time = pl031_stv2_read_time,
	422	.set_time = pl031_stv2_set_time,
	423	.read_alarm = pl031_stv2_read_alarm,
	424	.set_alarm = pl031_stv2_set_alarm,
	425	.alarm_irq_enable = pl031_alarm_irq_enable,
	426	},
c72881e8 LW	427	};
c72881e8 LW	428
2c39c9e1	429	static struct amba_id pl031_ids[] = {
8ae6e163	430	{
2934d6a8 LW	431	.id = 0x00041031,
2934d6a8 LW	432	.mask = 0x000fffff,
aff05ed5	433	.data = &arm_pl031,
c72881e8 LW	434	},
	435	/* ST Micro variants */
	436	{
	437	.id = 0x00180031,
	438	.mask = 0x00ffffff,
aff05ed5	439	.data = &stv1_pl031,
c72881e8 LW	440	},
	441	{
	442	.id = 0x00280031,
	443	.mask = 0x00ffffff,
aff05ed5	444	.data = &stv2_pl031,
2934d6a8	445	},
8ae6e163 DS	446	{0, 0},
	447	};
	448
f5feac2a DM	449	MODULE_DEVICE_TABLE(amba, pl031_ids);
f5feac2a DM	450
8ae6e163 DS	451	static struct amba_driver pl031_driver = {
	452	.drv = {
	453	.name = "rtc-pl031",
	454	},
	455	.id_table = pl031_ids,
	456	.probe = pl031_probe,
	457	.remove = pl031_remove,
	458	};
	459
9e5ed094	460	module_amba_driver(pl031_driver);
8ae6e163 DS	461
	462	MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net");
	463	MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
	464	MODULE_LICENSE("GPL");