[linux-2.6-block.git] / drivers / rtc / rtc-ab8500.c

/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * License terms: GNU General Public License (GPL) version 2
 * Author: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>
 *
 * RTC clock driver for the RTC part of the AB8500 Power management chip.
 * Based on RTC clock driver for the AB3100 Analog Baseband Chip by
 * Linus Walleij <linus.walleij@stericsson.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/mfd/abx500.h>
#include <linux/mfd/abx500/ab8500.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/pm_wakeirq.h>

#define AB8500_RTC_SOFF_STAT_REG	0x00
#define AB8500_RTC_CC_CONF_REG		0x01
#define AB8500_RTC_READ_REQ_REG		0x02
#define AB8500_RTC_WATCH_TSECMID_REG	0x03
#define AB8500_RTC_WATCH_TSECHI_REG	0x04
#define AB8500_RTC_WATCH_TMIN_LOW_REG	0x05
#define AB8500_RTC_WATCH_TMIN_MID_REG	0x06
#define AB8500_RTC_WATCH_TMIN_HI_REG	0x07
#define AB8500_RTC_ALRM_MIN_LOW_REG	0x08
#define AB8500_RTC_ALRM_MIN_MID_REG	0x09
#define AB8500_RTC_ALRM_MIN_HI_REG	0x0A
#define AB8500_RTC_STAT_REG		0x0B
#define AB8500_RTC_BKUP_CHG_REG		0x0C
#define AB8500_RTC_FORCE_BKUP_REG	0x0D
#define AB8500_RTC_CALIB_REG		0x0E
#define AB8500_RTC_SWITCH_STAT_REG	0x0F
#define AB8540_RTC_ALRM_SEC		0x22
#define AB8540_RTC_ALRM_MIN_LOW_REG	0x23
#define AB8540_RTC_ALRM_MIN_MID_REG	0x24
#define AB8540_RTC_ALRM_MIN_HI_REG	0x25

/* RtcReadRequest bits */
#define RTC_READ_REQUEST		0x01
#define RTC_WRITE_REQUEST		0x02

/* RtcCtrl bits */
#define RTC_ALARM_ENA			0x04
#define RTC_STATUS_DATA			0x01

#define COUNTS_PER_SEC			(0xF000 / 60)
#define AB8500_RTC_EPOCH		2000

static const u8 ab8500_rtc_time_regs[] = {
	AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
	AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,
	AB8500_RTC_WATCH_TSECMID_REG
};

static const u8 ab8500_rtc_alarm_regs[] = {
	AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
	AB8500_RTC_ALRM_MIN_LOW_REG
};

static const u8 ab8540_rtc_alarm_regs[] = {
	AB8540_RTC_ALRM_MIN_HI_REG, AB8540_RTC_ALRM_MIN_MID_REG,
	AB8540_RTC_ALRM_MIN_LOW_REG, AB8540_RTC_ALRM_SEC
};

/* Calculate the seconds from 1970 to 01-01-2000 00:00:00 */
static unsigned long get_elapsed_seconds(int year)
{
	unsigned long secs;
	struct rtc_time tm = {
		.tm_year = year - 1900,
		.tm_mday = 1,
	};

	/*
	 * This function calculates secs from 1970 and not from
	 * 1900, even if we supply the offset from year 1900.
	 */
	rtc_tm_to_time(&tm, &secs);
	return secs;
}

static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	unsigned long timeout = jiffies + HZ;
	int retval, i;
	unsigned long mins, secs;
	unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
	u8 value;

	/* Request a data read */
	retval = abx500_set_register_interruptible(dev,
		AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);
	if (retval < 0)
		return retval;

	/* Wait for some cycles after enabling the rtc read in ab8500 */
	while (time_before(jiffies, timeout)) {
		retval = abx500_get_register_interruptible(dev,
			AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);
		if (retval < 0)
			return retval;

		if (!(value & RTC_READ_REQUEST))
			break;

		usleep_range(1000, 5000);
	}

	/* Read the Watchtime registers */
	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
		retval = abx500_get_register_interruptible(dev,
			AB8500_RTC, ab8500_rtc_time_regs[i], &value);
		if (retval < 0)
			return retval;
		buf[i] = value;
	}

	mins = (buf[0] << 16) | (buf[1] << 8) | buf[2];

	secs =	(buf[3] << 8) | buf[4];
	secs =	secs / COUNTS_PER_SEC;
	secs =	secs + (mins * 60);

	/* Add back the initially subtracted number of seconds */
	secs += get_elapsed_seconds(AB8500_RTC_EPOCH);

	rtc_time_to_tm(secs, tm);
	return rtc_valid_tm(tm);
}

static int ab8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	int retval, i;
	unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
	unsigned long no_secs, no_mins, secs = 0;

	if (tm->tm_year < (AB8500_RTC_EPOCH - 1900)) {
		dev_dbg(dev, "year should be equal to or greater than %d\n",
				AB8500_RTC_EPOCH);
		return -EINVAL;
	}

	/* Get the number of seconds since 1970 */
	rtc_tm_to_time(tm, &secs);

	/*
	 * Convert it to the number of seconds since 01-01-2000 00:00:00, since
	 * we only have a small counter in the RTC.
	 */
	secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);

	no_mins = secs / 60;

	no_secs = secs % 60;
	/* Make the seconds count as per the RTC resolution */
	no_secs = no_secs * COUNTS_PER_SEC;

	buf[4] = no_secs & 0xFF;
	buf[3] = (no_secs >> 8) & 0xFF;

	buf[2] = no_mins & 0xFF;
	buf[1] = (no_mins >> 8) & 0xFF;
	buf[0] = (no_mins >> 16) & 0xFF;

	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
		retval = abx500_set_register_interruptible(dev, AB8500_RTC,
			ab8500_rtc_time_regs[i], buf[i]);
		if (retval < 0)
			return retval;
	}

	/* Request a data write */
	return abx500_set_register_interruptible(dev, AB8500_RTC,
		AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST);
}

static int ab8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	int retval, i;
	u8 rtc_ctrl, value;
	unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
	unsigned long secs, mins;

	/* Check if the alarm is enabled or not */
	retval = abx500_get_register_interruptible(dev, AB8500_RTC,
		AB8500_RTC_STAT_REG, &rtc_ctrl);
	if (retval < 0)
		return retval;

	if (rtc_ctrl & RTC_ALARM_ENA)
		alarm->enabled = 1;
	else
		alarm->enabled = 0;

	alarm->pending = 0;

	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
		retval = abx500_get_register_interruptible(dev, AB8500_RTC,
			ab8500_rtc_alarm_regs[i], &value);
		if (retval < 0)
			return retval;
		buf[i] = value;
	}

	mins = (buf[0] << 16) | (buf[1] << 8) | (buf[2]);
	secs = mins * 60;

	/* Add back the initially subtracted number of seconds */
	secs += get_elapsed_seconds(AB8500_RTC_EPOCH);

	rtc_time_to_tm(secs, &alarm->time);

	return rtc_valid_tm(&alarm->time);
}

static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled)
{
	return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC,
		AB8500_RTC_STAT_REG, RTC_ALARM_ENA,
		enabled ? RTC_ALARM_ENA : 0);
}

static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	int retval, i;
	unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
	unsigned long mins, secs = 0, cursec = 0;
	struct rtc_time curtm;

	if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
		dev_dbg(dev, "year should be equal to or greater than %d\n",
				AB8500_RTC_EPOCH);
		return -EINVAL;
	}

	/* Get the number of seconds since 1970 */
	rtc_tm_to_time(&alarm->time, &secs);

	/*
	 * Check whether alarm is set less than 1min.
	 * Since our RTC doesn't support alarm resolution less than 1min,
	 * return -EINVAL, so UIE EMUL can take it up, incase of UIE_ON
	 */
	ab8500_rtc_read_time(dev, &curtm); /* Read current time */
	rtc_tm_to_time(&curtm, &cursec);
	if ((secs - cursec) < 59) {
		dev_dbg(dev, "Alarm less than 1 minute not supported\r\n");
		return -EINVAL;
	}

	/*
	 * Convert it to the number of seconds since 01-01-2000 00:00:00, since
	 * we only have a small counter in the RTC.
	 */
	secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);

	mins = secs / 60;

	buf[2] = mins & 0xFF;
	buf[1] = (mins >> 8) & 0xFF;
	buf[0] = (mins >> 16) & 0xFF;

	/* Set the alarm time */
	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
		retval = abx500_set_register_interruptible(dev, AB8500_RTC,
			ab8500_rtc_alarm_regs[i], buf[i]);
		if (retval < 0)
			return retval;
	}

	return ab8500_rtc_irq_enable(dev, alarm->enabled);
}

static int ab8540_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
	int retval, i;
	unsigned char buf[ARRAY_SIZE(ab8540_rtc_alarm_regs)];
	unsigned long mins, secs = 0;

	if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
		dev_dbg(dev, "year should be equal to or greater than %d\n",
				AB8500_RTC_EPOCH);
		return -EINVAL;
	}

	/* Get the number of seconds since 1970 */
	rtc_tm_to_time(&alarm->time, &secs);

	/*
	 * Convert it to the number of seconds since 01-01-2000 00:00:00
	 */
	secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
	mins = secs / 60;

	buf[3] = secs % 60;
	buf[2] = mins & 0xFF;
	buf[1] = (mins >> 8) & 0xFF;
	buf[0] = (mins >> 16) & 0xFF;

	/* Set the alarm time */
	for (i = 0; i < ARRAY_SIZE(ab8540_rtc_alarm_regs); i++) {
		retval = abx500_set_register_interruptible(dev, AB8500_RTC,
			ab8540_rtc_alarm_regs[i], buf[i]);
		if (retval < 0)
			return retval;
	}

	return ab8500_rtc_irq_enable(dev, alarm->enabled);
}

static int ab8500_rtc_set_calibration(struct device *dev, int calibration)
{
	int retval;
	u8  rtccal = 0;

	/*
	 * Check that the calibration value (which is in units of 0.5
	 * parts-per-million) is in the AB8500's range for RtcCalibration
	 * register. -128 (0x80) is not permitted because the AB8500 uses
	 * a sign-bit rather than two's complement, so 0x80 is just another
	 * representation of zero.
	 */
	if ((calibration < -127) || (calibration > 127)) {
		dev_err(dev, "RtcCalibration value outside permitted range\n");
		return -EINVAL;
	}

	/*
	 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
	 * so need to convert to this sort of representation before writing
	 * into RtcCalibration register...
	 */
	if (calibration >= 0)
		rtccal = 0x7F & calibration;
	else
		rtccal = ~(calibration - 1) | 0x80;

	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
			AB8500_RTC_CALIB_REG, rtccal);

	return retval;
}

static int ab8500_rtc_get_calibration(struct device *dev, int *calibration)
{
	int retval;
	u8  rtccal = 0;

	retval =  abx500_get_register_interruptible(dev, AB8500_RTC,
			AB8500_RTC_CALIB_REG, &rtccal);
	if (retval >= 0) {
		/*
		 * The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
		 * so need to convert value from RtcCalibration register into
		 * a two's complement signed value...
		 */
		if (rtccal & 0x80)
			*calibration = 0 - (rtccal & 0x7F);
		else
			*calibration = 0x7F & rtccal;
	}

	return retval;
}

static ssize_t ab8500_sysfs_store_rtc_calibration(struct device *dev,
				struct device_attribute *attr,
				const char *buf, size_t count)
{
	int retval;
	int calibration = 0;

	if (sscanf(buf, " %i ", &calibration) != 1) {
		dev_err(dev, "Failed to store RTC calibration attribute\n");
		return -EINVAL;
	}

	retval = ab8500_rtc_set_calibration(dev, calibration);

	return retval ? retval : count;
}

static ssize_t ab8500_sysfs_show_rtc_calibration(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	int  retval = 0;
	int  calibration = 0;

	retval = ab8500_rtc_get_calibration(dev, &calibration);
	if (retval < 0) {
		dev_err(dev, "Failed to read RTC calibration attribute\n");
		sprintf(buf, "0\n");
		return retval;
	}

	return sprintf(buf, "%d\n", calibration);
}

static DEVICE_ATTR(rtc_calibration, S_IRUGO | S_IWUSR,
		   ab8500_sysfs_show_rtc_calibration,
		   ab8500_sysfs_store_rtc_calibration);

static int ab8500_sysfs_rtc_register(struct device *dev)
{
	return device_create_file(dev, &dev_attr_rtc_calibration);
}

static void ab8500_sysfs_rtc_unregister(struct device *dev)
{
	device_remove_file(dev, &dev_attr_rtc_calibration);
}

static irqreturn_t rtc_alarm_handler(int irq, void *data)
{
	struct rtc_device *rtc = data;
	unsigned long events = RTC_IRQF | RTC_AF;

	dev_dbg(&rtc->dev, "%s\n", __func__);
	rtc_update_irq(rtc, 1, events);

	return IRQ_HANDLED;
}

static const struct rtc_class_ops ab8500_rtc_ops = {
	.read_time		= ab8500_rtc_read_time,
	.set_time		= ab8500_rtc_set_time,
	.read_alarm		= ab8500_rtc_read_alarm,
	.set_alarm		= ab8500_rtc_set_alarm,
	.alarm_irq_enable	= ab8500_rtc_irq_enable,
};

static const struct rtc_class_ops ab8540_rtc_ops = {
	.read_time		= ab8500_rtc_read_time,
	.set_time		= ab8500_rtc_set_time,
	.read_alarm		= ab8500_rtc_read_alarm,
	.set_alarm		= ab8540_rtc_set_alarm,
	.alarm_irq_enable	= ab8500_rtc_irq_enable,
};

static const struct platform_device_id ab85xx_rtc_ids[] = {
	{ "ab8500-rtc", (kernel_ulong_t)&ab8500_rtc_ops, },
	{ "ab8540-rtc", (kernel_ulong_t)&ab8540_rtc_ops, },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, ab85xx_rtc_ids);

static int ab8500_rtc_probe(struct platform_device *pdev)
{
	const struct platform_device_id *platid = platform_get_device_id(pdev);
	int err;
	struct rtc_device *rtc;
	u8 rtc_ctrl;
	int irq;

	irq = platform_get_irq_byname(pdev, "ALARM");
	if (irq < 0)
		return irq;

	/* For RTC supply test */
	err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC,
		AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA);
	if (err < 0)
		return err;

	/* Wait for reset by the PorRtc */
	usleep_range(1000, 5000);

	err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC,
		AB8500_RTC_STAT_REG, &rtc_ctrl);
	if (err < 0)
		return err;

	/* Check if the RTC Supply fails */
	if (!(rtc_ctrl & RTC_STATUS_DATA)) {
		dev_err(&pdev->dev, "RTC supply failure\n");
		return -ENODEV;
	}

	device_init_wakeup(&pdev->dev, true);

	rtc = devm_rtc_device_register(&pdev->dev, "ab8500-rtc",
				(struct rtc_class_ops *)platid->driver_data,
				THIS_MODULE);
	if (IS_ERR(rtc)) {
		dev_err(&pdev->dev, "Registration failed\n");
		err = PTR_ERR(rtc);
		return err;
	}

	err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
			rtc_alarm_handler, IRQF_ONESHOT,
			"ab8500-rtc", rtc);
	if (err < 0)
		return err;

	dev_pm_set_wake_irq(&pdev->dev, irq);
	platform_set_drvdata(pdev, rtc);

	err = ab8500_sysfs_rtc_register(&pdev->dev);
	if (err) {
		dev_err(&pdev->dev, "sysfs RTC failed to register\n");
		return err;
	}

	rtc->uie_unsupported = 1;

	return 0;
}

static int ab8500_rtc_remove(struct platform_device *pdev)
{
	dev_pm_clear_wake_irq(&pdev->dev);
	device_init_wakeup(&pdev->dev, false);
	ab8500_sysfs_rtc_unregister(&pdev->dev);

	return 0;
}

static struct platform_driver ab8500_rtc_driver = {
	.driver = {
		.name = "ab8500-rtc",
	},
	.probe	= ab8500_rtc_probe,
	.remove = ab8500_rtc_remove,
	.id_table = ab85xx_rtc_ids,
};

module_platform_driver(ab8500_rtc_driver);

MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>");
MODULE_DESCRIPTION("AB8500 RTC Driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
0af62f4d VS	1	/*
	2	* Copyright (C) ST-Ericsson SA 2010
	3	*
	4	* License terms: GNU General Public License (GPL) version 2
	5	* Author: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>
	6	*
	7	* RTC clock driver for the RTC part of the AB8500 Power management chip.
	8	* Based on RTC clock driver for the AB3100 Analog Baseband Chip by
	9	* Linus Walleij <linus.walleij@stericsson.com>
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/kernel.h>
	14	#include <linux/init.h>
	15	#include <linux/platform_device.h>
	16	#include <linux/rtc.h>
47c16975	17	#include <linux/mfd/abx500.h>
ee66e653	18	#include <linux/mfd/abx500/ab8500.h>
0af62f4d	19	#include <linux/delay.h>
ad49fcbe	20	#include <linux/of.h>
93a6f916	21	#include <linux/pm_wakeirq.h>
0af62f4d	22
47c16975 MW	23	#define AB8500_RTC_SOFF_STAT_REG 0x00
	24	#define AB8500_RTC_CC_CONF_REG 0x01
	25	#define AB8500_RTC_READ_REQ_REG 0x02
	26	#define AB8500_RTC_WATCH_TSECMID_REG 0x03
	27	#define AB8500_RTC_WATCH_TSECHI_REG 0x04
	28	#define AB8500_RTC_WATCH_TMIN_LOW_REG 0x05
	29	#define AB8500_RTC_WATCH_TMIN_MID_REG 0x06
	30	#define AB8500_RTC_WATCH_TMIN_HI_REG 0x07
	31	#define AB8500_RTC_ALRM_MIN_LOW_REG 0x08
	32	#define AB8500_RTC_ALRM_MIN_MID_REG 0x09
	33	#define AB8500_RTC_ALRM_MIN_HI_REG 0x0A
	34	#define AB8500_RTC_STAT_REG 0x0B
	35	#define AB8500_RTC_BKUP_CHG_REG 0x0C
	36	#define AB8500_RTC_FORCE_BKUP_REG 0x0D
	37	#define AB8500_RTC_CALIB_REG 0x0E
	38	#define AB8500_RTC_SWITCH_STAT_REG 0x0F
25d053cf AT	39	#define AB8540_RTC_ALRM_SEC 0x22
	40	#define AB8540_RTC_ALRM_MIN_LOW_REG 0x23
	41	#define AB8540_RTC_ALRM_MIN_MID_REG 0x24
	42	#define AB8540_RTC_ALRM_MIN_HI_REG 0x25
0af62f4d VS	43
	44	/* RtcReadRequest bits */
	45	#define RTC_READ_REQUEST 0x01
	46	#define RTC_WRITE_REQUEST 0x02
	47
	48	/* RtcCtrl bits */
	49	#define RTC_ALARM_ENA 0x04
	50	#define RTC_STATUS_DATA 0x01
	51
	52	#define COUNTS_PER_SEC (0xF000 / 60)
	53	#define AB8500_RTC_EPOCH 2000
	54
47c16975	55	static const u8 ab8500_rtc_time_regs[] = {
0af62f4d VS	56	AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
	57	AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,
	58	AB8500_RTC_WATCH_TSECMID_REG
	59	};
	60
47c16975	61	static const u8 ab8500_rtc_alarm_regs[] = {
0af62f4d VS	62	AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
	63	AB8500_RTC_ALRM_MIN_LOW_REG
	64	};
	65
25d053cf AT	66	static const u8 ab8540_rtc_alarm_regs[] = {
	67	AB8540_RTC_ALRM_MIN_HI_REG, AB8540_RTC_ALRM_MIN_MID_REG,
	68	AB8540_RTC_ALRM_MIN_LOW_REG, AB8540_RTC_ALRM_SEC
	69	};
	70
0af62f4d VS	71	/* Calculate the seconds from 1970 to 01-01-2000 00:00:00 */
	72	static unsigned long get_elapsed_seconds(int year)
	73	{
	74	unsigned long secs;
	75	struct rtc_time tm = {
	76	.tm_year = year - 1900,
	77	.tm_mday = 1,
	78	};
	79
	80	/*
	81	* This function calculates secs from 1970 and not from
	82	* 1900, even if we supply the offset from year 1900.
	83	*/
	84	rtc_tm_to_time(&tm, &secs);
	85	return secs;
	86	}
	87
	88	static int ab8500_rtc_read_time(struct device dev, struct rtc_time tm)
	89	{
0af62f4d VS	90	unsigned long timeout = jiffies + HZ;
	91	int retval, i;
	92	unsigned long mins, secs;
	93	unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
47c16975	94	u8 value;
0af62f4d VS	95
0af62f4d VS	96	/* Request a data read */
47c16975 MW	97	retval = abx500_set_register_interruptible(dev,
47c16975 MW	98	AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);
0af62f4d VS	99	if (retval < 0)
	100	return retval;
	101
064407f1 BJ	102	/* Wait for some cycles after enabling the rtc read in ab8500 */
	103	while (time_before(jiffies, timeout)) {
	104	retval = abx500_get_register_interruptible(dev,
	105	AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);
	106	if (retval < 0)
	107	return retval;
	108
	109	if (!(value & RTC_READ_REQUEST))
	110	break;
	111
	112	usleep_range(1000, 5000);
0af62f4d VS	113	}
	114
	115	/* Read the Watchtime registers */
	116	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
47c16975 MW	117	retval = abx500_get_register_interruptible(dev,
47c16975 MW	118	AB8500_RTC, ab8500_rtc_time_regs[i], &value);
0af62f4d VS	119	if (retval < 0)
0af62f4d VS	120	return retval;
47c16975	121	buf[i] = value;
0af62f4d VS	122	}
	123
	124	mins = (buf[0] << 16) \| (buf[1] << 8) \| buf[2];
	125
	126	secs = (buf[3] << 8) \| buf[4];
	127	secs = secs / COUNTS_PER_SEC;
	128	secs = secs + (mins * 60);
	129
	130	/* Add back the initially subtracted number of seconds */
	131	secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
	132
	133	rtc_time_to_tm(secs, tm);
	134	return rtc_valid_tm(tm);
	135	}
	136
	137	static int ab8500_rtc_set_time(struct device dev, struct rtc_time tm)
	138	{
0af62f4d VS	139	int retval, i;
	140	unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
	141	unsigned long no_secs, no_mins, secs = 0;
	142
	143	if (tm->tm_year < (AB8500_RTC_EPOCH - 1900)) {
	144	dev_dbg(dev, "year should be equal to or greater than %d\n",
	145	AB8500_RTC_EPOCH);
	146	return -EINVAL;
	147	}
	148
	149	/* Get the number of seconds since 1970 */
	150	rtc_tm_to_time(tm, &secs);
	151
	152	/*
	153	* Convert it to the number of seconds since 01-01-2000 00:00:00, since
	154	* we only have a small counter in the RTC.
	155	*/
	156	secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
	157
	158	no_mins = secs / 60;
	159
	160	no_secs = secs % 60;
	161	/* Make the seconds count as per the RTC resolution */
	162	no_secs = no_secs * COUNTS_PER_SEC;
	163
	164	buf[4] = no_secs & 0xFF;
	165	buf[3] = (no_secs >> 8) & 0xFF;
	166
	167	buf[2] = no_mins & 0xFF;
	168	buf[1] = (no_mins >> 8) & 0xFF;
	169	buf[0] = (no_mins >> 16) & 0xFF;
	170
	171	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
47c16975 MW	172	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
47c16975 MW	173	ab8500_rtc_time_regs[i], buf[i]);
0af62f4d VS	174	if (retval < 0)
	175	return retval;
	176	}
	177
	178	/* Request a data write */
47c16975 MW	179	return abx500_set_register_interruptible(dev, AB8500_RTC,
47c16975 MW	180	AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST);
0af62f4d VS	181	}
	182
	183	static int ab8500_rtc_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	184	{
0af62f4d	185	int retval, i;
47c16975	186	u8 rtc_ctrl, value;
0af62f4d VS	187	unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
	188	unsigned long secs, mins;
	189
	190	/* Check if the alarm is enabled or not */
47c16975 MW	191	retval = abx500_get_register_interruptible(dev, AB8500_RTC,
	192	AB8500_RTC_STAT_REG, &rtc_ctrl);
	193	if (retval < 0)
	194	return retval;
0af62f4d VS	195
	196	if (rtc_ctrl & RTC_ALARM_ENA)
	197	alarm->enabled = 1;
	198	else
	199	alarm->enabled = 0;
	200
	201	alarm->pending = 0;
	202
	203	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
47c16975 MW	204	retval = abx500_get_register_interruptible(dev, AB8500_RTC,
47c16975 MW	205	ab8500_rtc_alarm_regs[i], &value);
0af62f4d VS	206	if (retval < 0)
0af62f4d VS	207	return retval;
47c16975	208	buf[i] = value;
0af62f4d VS	209	}
	210
	211	mins = (buf[0] << 16) \| (buf[1] << 8) \| (buf[2]);
	212	secs = mins * 60;
	213
	214	/* Add back the initially subtracted number of seconds */
	215	secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
	216
	217	rtc_time_to_tm(secs, &alarm->time);
	218
	219	return rtc_valid_tm(&alarm->time);
	220	}
	221
	222	static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled)
	223	{
47c16975 MW	224	return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC,
	225	AB8500_RTC_STAT_REG, RTC_ALARM_ENA,
	226	enabled ? RTC_ALARM_ENA : 0);
0af62f4d VS	227	}
	228
	229	static int ab8500_rtc_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	230	{
0af62f4d VS	231	int retval, i;
0af62f4d VS	232	unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
dc43d4a2 RC	233	unsigned long mins, secs = 0, cursec = 0;
dc43d4a2 RC	234	struct rtc_time curtm;
0af62f4d VS	235
	236	if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
	237	dev_dbg(dev, "year should be equal to or greater than %d\n",
	238	AB8500_RTC_EPOCH);
	239	return -EINVAL;
	240	}
	241
	242	/* Get the number of seconds since 1970 */
	243	rtc_tm_to_time(&alarm->time, &secs);
	244
dc43d4a2 RC	245	/*
	246	* Check whether alarm is set less than 1min.
	247	* Since our RTC doesn't support alarm resolution less than 1min,
	248	* return -EINVAL, so UIE EMUL can take it up, incase of UIE_ON
	249	*/
	250	ab8500_rtc_read_time(dev, &curtm); /* Read current time */
	251	rtc_tm_to_time(&curtm, &cursec);
	252	if ((secs - cursec) < 59) {
	253	dev_dbg(dev, "Alarm less than 1 minute not supported\r\n");
	254	return -EINVAL;
	255	}
	256
0af62f4d VS	257	/*
	258	* Convert it to the number of seconds since 01-01-2000 00:00:00, since
	259	* we only have a small counter in the RTC.
	260	*/
	261	secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
	262
	263	mins = secs / 60;
	264
	265	buf[2] = mins & 0xFF;
	266	buf[1] = (mins >> 8) & 0xFF;
	267	buf[0] = (mins >> 16) & 0xFF;
	268
	269	/* Set the alarm time */
	270	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
47c16975 MW	271	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
47c16975 MW	272	ab8500_rtc_alarm_regs[i], buf[i]);
0af62f4d VS	273	if (retval < 0)
	274	return retval;
	275	}
	276
	277	return ab8500_rtc_irq_enable(dev, alarm->enabled);
	278	}
	279
25d053cf AT	280	static int ab8540_rtc_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	281	{
	282	int retval, i;
	283	unsigned char buf[ARRAY_SIZE(ab8540_rtc_alarm_regs)];
	284	unsigned long mins, secs = 0;
	285
	286	if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
	287	dev_dbg(dev, "year should be equal to or greater than %d\n",
	288	AB8500_RTC_EPOCH);
	289	return -EINVAL;
	290	}
	291
	292	/* Get the number of seconds since 1970 */
	293	rtc_tm_to_time(&alarm->time, &secs);
	294
	295	/*
	296	* Convert it to the number of seconds since 01-01-2000 00:00:00
	297	*/
	298	secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
	299	mins = secs / 60;
	300
	301	buf[3] = secs % 60;
	302	buf[2] = mins & 0xFF;
	303	buf[1] = (mins >> 8) & 0xFF;
	304	buf[0] = (mins >> 16) & 0xFF;
	305
	306	/* Set the alarm time */
	307	for (i = 0; i < ARRAY_SIZE(ab8540_rtc_alarm_regs); i++) {
	308	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
	309	ab8540_rtc_alarm_regs[i], buf[i]);
	310	if (retval < 0)
	311	return retval;
	312	}
	313
	314	return ab8500_rtc_irq_enable(dev, alarm->enabled);
	315	}
dda367ac MG	316
	317	static int ab8500_rtc_set_calibration(struct device *dev, int calibration)
	318	{
	319	int retval;
	320	u8 rtccal = 0;
	321
	322	/*
	323	* Check that the calibration value (which is in units of 0.5
	324	* parts-per-million) is in the AB8500's range for RtcCalibration
	325	* register. -128 (0x80) is not permitted because the AB8500 uses
	326	* a sign-bit rather than two's complement, so 0x80 is just another
	327	* representation of zero.
	328	*/
	329	if ((calibration < -127) \|\| (calibration > 127)) {
	330	dev_err(dev, "RtcCalibration value outside permitted range\n");
	331	return -EINVAL;
	332	}
	333
	334	/*
	335	* The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
	336	* so need to convert to this sort of representation before writing
	337	* into RtcCalibration register...
	338	*/
	339	if (calibration >= 0)
	340	rtccal = 0x7F & calibration;
	341	else
	342	rtccal = ~(calibration - 1) \| 0x80;
	343
	344	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
	345	AB8500_RTC_CALIB_REG, rtccal);
	346
	347	return retval;
	348	}
	349
	350	static int ab8500_rtc_get_calibration(struct device dev, int calibration)
	351	{
	352	int retval;
	353	u8 rtccal = 0;
	354
	355	retval = abx500_get_register_interruptible(dev, AB8500_RTC,
	356	AB8500_RTC_CALIB_REG, &rtccal);
	357	if (retval >= 0) {
	358	/*
	359	* The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
	360	* so need to convert value from RtcCalibration register into
	361	* a two's complement signed value...
	362	*/
	363	if (rtccal & 0x80)
	364	*calibration = 0 - (rtccal & 0x7F);
	365	else
	366	*calibration = 0x7F & rtccal;
	367	}
	368
	369	return retval;
	370	}
	371
	372	static ssize_t ab8500_sysfs_store_rtc_calibration(struct device *dev,
	373	struct device_attribute *attr,
	374	const char *buf, size_t count)
	375	{
	376	int retval;
	377	int calibration = 0;
	378
	379	if (sscanf(buf, " %i ", &calibration) != 1) {
380	dev_err(dev, "Failed to store RTC calibration attribute\n");
381	return -EINVAL;
382	}
383
384	retval = ab8500_rtc_set_calibration(dev, calibration);
385
386	return retval ? retval : count;
387	}
388
389	static ssize_t ab8500_sysfs_show_rtc_calibration(struct device *dev,
390	struct device_attribute attr, char buf)
391	{
392	int retval = 0;
393	int calibration = 0;
394
395	retval = ab8500_rtc_get_calibration(dev, &calibration);
396	if (retval < 0) {
397	dev_err(dev, "Failed to read RTC calibration attribute\n");
398	sprintf(buf, "0\n");
399	return retval;
400	}
401
402	return sprintf(buf, "%d\n", calibration);
403	}
404
405	static DEVICE_ATTR(rtc_calibration, S_IRUGO \| S_IWUSR,
406	ab8500_sysfs_show_rtc_calibration,
407	ab8500_sysfs_store_rtc_calibration);
408
409	static int ab8500_sysfs_rtc_register(struct device *dev)
410	{
411	return device_create_file(dev, &dev_attr_rtc_calibration);
412	}
413
414	static void ab8500_sysfs_rtc_unregister(struct device *dev)
415	{
416	device_remove_file(dev, &dev_attr_rtc_calibration);
417	}
418
0af62f4d VS	419	static irqreturn_t rtc_alarm_handler(int irq, void *data)
	420	{
	421	struct rtc_device *rtc = data;
	422	unsigned long events = RTC_IRQF \| RTC_AF;
	423
	424	dev_dbg(&rtc->dev, "%s\n", __func__);
	425	rtc_update_irq(rtc, 1, events);
	426
	427	return IRQ_HANDLED;
	428	}
	429
	430	static const struct rtc_class_ops ab8500_rtc_ops = {
	431	.read_time = ab8500_rtc_read_time,
	432	.set_time = ab8500_rtc_set_time,
	433	.read_alarm = ab8500_rtc_read_alarm,
	434	.set_alarm = ab8500_rtc_set_alarm,
	435	.alarm_irq_enable = ab8500_rtc_irq_enable,
	436	};
	437
25d053cf AT	438	static const struct rtc_class_ops ab8540_rtc_ops = {
	439	.read_time = ab8500_rtc_read_time,
	440	.set_time = ab8500_rtc_set_time,
	441	.read_alarm = ab8500_rtc_read_alarm,
	442	.set_alarm = ab8540_rtc_set_alarm,
	443	.alarm_irq_enable = ab8500_rtc_irq_enable,
	444	};
	445
9a72f410	446	static const struct platform_device_id ab85xx_rtc_ids[] = {
25d053cf AT	447	{ "ab8500-rtc", (kernel_ulong_t)&ab8500_rtc_ops, },
25d053cf AT	448	{ "ab8540-rtc", (kernel_ulong_t)&ab8540_rtc_ops, },
8a67e931	449	{ /* sentinel */ }
25d053cf	450	};
63074cc3	451	MODULE_DEVICE_TABLE(platform, ab85xx_rtc_ids);
25d053cf	452
5a167f45	453	static int ab8500_rtc_probe(struct platform_device *pdev)
0af62f4d	454	{
25d053cf	455	const struct platform_device_id *platid = platform_get_device_id(pdev);
0af62f4d VS	456	int err;
0af62f4d VS	457	struct rtc_device *rtc;
47c16975	458	u8 rtc_ctrl;
0af62f4d VS	459	int irq;
	460
	461	irq = platform_get_irq_byname(pdev, "ALARM");
	462	if (irq < 0)
	463	return irq;
	464
	465	/* For RTC supply test */
47c16975 MW	466	err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC,
47c16975 MW	467	AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA);
0af62f4d VS	468	if (err < 0)
	469	return err;
	470
	471	/* Wait for reset by the PorRtc */
012e52e1	472	usleep_range(1000, 5000);
0af62f4d	473
47c16975 MW	474	err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC,
	475	AB8500_RTC_STAT_REG, &rtc_ctrl);
	476	if (err < 0)
	477	return err;
0af62f4d VS	478
	479	/* Check if the RTC Supply fails */
	480	if (!(rtc_ctrl & RTC_STATUS_DATA)) {
	481	dev_err(&pdev->dev, "RTC supply failure\n");
	482	return -ENODEV;
	483	}
	484
b62581e6 AL	485	device_init_wakeup(&pdev->dev, true);
b62581e6 AL	486
fa11f7e7	487	rtc = devm_rtc_device_register(&pdev->dev, "ab8500-rtc",
25d053cf AT	488	(struct rtc_class_ops *)platid->driver_data,
25d053cf AT	489	THIS_MODULE);
0af62f4d VS	490	if (IS_ERR(rtc)) {
	491	dev_err(&pdev->dev, "Registration failed\n");
	492	err = PTR_ERR(rtc);
	493	return err;
	494	}
	495
fa11f7e7	496	err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
93a6f916	497	rtc_alarm_handler, IRQF_ONESHOT,
fa11f7e7 JH	498	"ab8500-rtc", rtc);
fa11f7e7 JH	499	if (err < 0)
0af62f4d	500	return err;
0af62f4d	501
93a6f916	502	dev_pm_set_wake_irq(&pdev->dev, irq);
0af62f4d VS	503	platform_set_drvdata(pdev, rtc);
0af62f4d VS	504
dda367ac MG	505	err = ab8500_sysfs_rtc_register(&pdev->dev);
	506	if (err) {
	507	dev_err(&pdev->dev, "sysfs RTC failed to register\n");
	508	return err;
	509	}
	510
c594d678 XP	511	rtc->uie_unsupported = 1;
c594d678 XP	512
0af62f4d VS	513	return 0;
	514	}
	515
5a167f45	516	static int ab8500_rtc_remove(struct platform_device *pdev)
0af62f4d	517	{
93a6f916 SH	518	dev_pm_clear_wake_irq(&pdev->dev);
93a6f916 SH	519	device_init_wakeup(&pdev->dev, false);
dda367ac MG	520	ab8500_sysfs_rtc_unregister(&pdev->dev);
dda367ac MG	521
0af62f4d VS	522	return 0;
	523	}
	524
	525	static struct platform_driver ab8500_rtc_driver = {
	526	.driver = {
	527	.name = "ab8500-rtc",
0af62f4d VS	528	},
0af62f4d VS	529	.probe = ab8500_rtc_probe,
5a167f45	530	.remove = ab8500_rtc_remove,
25d053cf	531	.id_table = ab85xx_rtc_ids,
0af62f4d VS	532	};
0af62f4d VS	533
0c4eae66	534	module_platform_driver(ab8500_rtc_driver);
0af62f4d	535
0af62f4d VS	536	MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>");
	537	MODULE_DESCRIPTION("AB8500 RTC Driver");
	538	MODULE_LICENSE("GPL v2");