[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

/* 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)

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 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);

	rtc_time_to_tm(secs, tm);
	return 0;
}

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;

	rtc_tm_to_time(tm, &secs);

	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;

	rtc_time_to_tm(secs, &alarm->time);

	return 0;
}

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;

	/* 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;
	}

	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 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 struct attribute *ab8500_rtc_attrs[] = {
	&dev_attr_rtc_calibration.attr,
	NULL
};

static const struct attribute_group ab8500_rtc_sysfs_files = {
	.attrs	= ab8500_rtc_attrs,
};

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 platform_device_id ab85xx_rtc_ids[] = {
	{ "ab8500-rtc", (kernel_ulong_t)&ab8500_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_allocate_device(&pdev->dev);
	if (IS_ERR(rtc))
		return PTR_ERR(rtc);

	rtc->ops = (struct rtc_class_ops *)platid->driver_data;

	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);

	rtc->uie_unsupported = 1;

	rtc->range_max = (1ULL << 24) * 60 - 1; // 24-bit minutes + 59 secs
	rtc->start_secs = RTC_TIMESTAMP_BEGIN_2000;
	rtc->set_start_time = true;

	err = rtc_add_group(rtc, &ab8500_rtc_sysfs_files);
	if (err)
		return err;

	return rtc_register_device(rtc);
}

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

	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
0af62f4d VS	39
	40	/* RtcReadRequest bits */
	41	#define RTC_READ_REQUEST 0x01
	42	#define RTC_WRITE_REQUEST 0x02
	43
	44	/* RtcCtrl bits */
	45	#define RTC_ALARM_ENA 0x04
	46	#define RTC_STATUS_DATA 0x01
	47
	48	#define COUNTS_PER_SEC (0xF000 / 60)
0af62f4d	49
47c16975	50	static const u8 ab8500_rtc_time_regs[] = {
0af62f4d VS	51	AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
	52	AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,
	53	AB8500_RTC_WATCH_TSECMID_REG
	54	};
	55
47c16975	56	static const u8 ab8500_rtc_alarm_regs[] = {
0af62f4d VS	57	AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
	58	AB8500_RTC_ALRM_MIN_LOW_REG
	59	};
	60
0af62f4d VS	61	static int ab8500_rtc_read_time(struct device dev, struct rtc_time tm)
0af62f4d VS	62	{
0af62f4d VS	63	unsigned long timeout = jiffies + HZ;
	64	int retval, i;
	65	unsigned long mins, secs;
	66	unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
47c16975	67	u8 value;
0af62f4d VS	68
0af62f4d VS	69	/* Request a data read */
47c16975 MW	70	retval = abx500_set_register_interruptible(dev,
47c16975 MW	71	AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);
0af62f4d VS	72	if (retval < 0)
	73	return retval;
	74
064407f1 BJ	75	/* Wait for some cycles after enabling the rtc read in ab8500 */
	76	while (time_before(jiffies, timeout)) {
	77	retval = abx500_get_register_interruptible(dev,
	78	AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);
	79	if (retval < 0)
	80	return retval;
	81
	82	if (!(value & RTC_READ_REQUEST))
	83	break;
	84
	85	usleep_range(1000, 5000);
0af62f4d VS	86	}
	87
	88	/* Read the Watchtime registers */
	89	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
47c16975 MW	90	retval = abx500_get_register_interruptible(dev,
47c16975 MW	91	AB8500_RTC, ab8500_rtc_time_regs[i], &value);
0af62f4d VS	92	if (retval < 0)
0af62f4d VS	93	return retval;
47c16975	94	buf[i] = value;
0af62f4d VS	95	}
	96
	97	mins = (buf[0] << 16) \| (buf[1] << 8) \| buf[2];
	98
	99	secs = (buf[3] << 8) \| buf[4];
	100	secs = secs / COUNTS_PER_SEC;
	101	secs = secs + (mins * 60);
	102
0af62f4d	103	rtc_time_to_tm(secs, tm);
ab62670e	104	return 0;
0af62f4d VS	105	}
	106
	107	static int ab8500_rtc_set_time(struct device dev, struct rtc_time tm)
	108	{
0af62f4d VS	109	int retval, i;
	110	unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
	111	unsigned long no_secs, no_mins, secs = 0;
	112
0af62f4d VS	113	rtc_tm_to_time(tm, &secs);
0af62f4d VS	114
0af62f4d VS	115	no_mins = secs / 60;
	116
	117	no_secs = secs % 60;
	118	/* Make the seconds count as per the RTC resolution */
	119	no_secs = no_secs * COUNTS_PER_SEC;
	120
	121	buf[4] = no_secs & 0xFF;
	122	buf[3] = (no_secs >> 8) & 0xFF;
	123
	124	buf[2] = no_mins & 0xFF;
	125	buf[1] = (no_mins >> 8) & 0xFF;
	126	buf[0] = (no_mins >> 16) & 0xFF;
	127
	128	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
47c16975 MW	129	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
47c16975 MW	130	ab8500_rtc_time_regs[i], buf[i]);
0af62f4d VS	131	if (retval < 0)
	132	return retval;
	133	}
	134
	135	/* Request a data write */
47c16975 MW	136	return abx500_set_register_interruptible(dev, AB8500_RTC,
47c16975 MW	137	AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST);
0af62f4d VS	138	}
	139
	140	static int ab8500_rtc_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	141	{
0af62f4d	142	int retval, i;
47c16975	143	u8 rtc_ctrl, value;
0af62f4d VS	144	unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
	145	unsigned long secs, mins;
	146
	147	/* Check if the alarm is enabled or not */
47c16975 MW	148	retval = abx500_get_register_interruptible(dev, AB8500_RTC,
	149	AB8500_RTC_STAT_REG, &rtc_ctrl);
	150	if (retval < 0)
	151	return retval;
0af62f4d VS	152
	153	if (rtc_ctrl & RTC_ALARM_ENA)
	154	alarm->enabled = 1;
	155	else
	156	alarm->enabled = 0;
	157
	158	alarm->pending = 0;
	159
	160	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
47c16975 MW	161	retval = abx500_get_register_interruptible(dev, AB8500_RTC,
47c16975 MW	162	ab8500_rtc_alarm_regs[i], &value);
0af62f4d VS	163	if (retval < 0)
0af62f4d VS	164	return retval;
47c16975	165	buf[i] = value;
0af62f4d VS	166	}
	167
	168	mins = (buf[0] << 16) \| (buf[1] << 8) \| (buf[2]);
	169	secs = mins * 60;
	170
0af62f4d VS	171	rtc_time_to_tm(secs, &alarm->time);
0af62f4d VS	172
9a90a5bc	173	return 0;
0af62f4d VS	174	}
	175
	176	static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled)
	177	{
47c16975 MW	178	return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC,
	179	AB8500_RTC_STAT_REG, RTC_ALARM_ENA,
	180	enabled ? RTC_ALARM_ENA : 0);
0af62f4d VS	181	}
	182
	183	static int ab8500_rtc_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	184	{
0af62f4d VS	185	int retval, i;
0af62f4d VS	186	unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
dc43d4a2 RC	187	unsigned long mins, secs = 0, cursec = 0;
dc43d4a2 RC	188	struct rtc_time curtm;
0af62f4d	189
0af62f4d VS	190	/* Get the number of seconds since 1970 */
	191	rtc_tm_to_time(&alarm->time, &secs);
	192
dc43d4a2 RC	193	/*
	194	* Check whether alarm is set less than 1min.
	195	* Since our RTC doesn't support alarm resolution less than 1min,
	196	* return -EINVAL, so UIE EMUL can take it up, incase of UIE_ON
	197	*/
	198	ab8500_rtc_read_time(dev, &curtm); /* Read current time */
	199	rtc_tm_to_time(&curtm, &cursec);
	200	if ((secs - cursec) < 59) {
	201	dev_dbg(dev, "Alarm less than 1 minute not supported\r\n");
	202	return -EINVAL;
	203	}
	204
0af62f4d VS	205	mins = secs / 60;
	206
	207	buf[2] = mins & 0xFF;
	208	buf[1] = (mins >> 8) & 0xFF;
	209	buf[0] = (mins >> 16) & 0xFF;
	210
	211	/* Set the alarm time */
	212	for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
47c16975 MW	213	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
47c16975 MW	214	ab8500_rtc_alarm_regs[i], buf[i]);
0af62f4d VS	215	if (retval < 0)
	216	return retval;
	217	}
	218
	219	return ab8500_rtc_irq_enable(dev, alarm->enabled);
	220	}
	221
dda367ac MG	222	static int ab8500_rtc_set_calibration(struct device *dev, int calibration)
	223	{
	224	int retval;
	225	u8 rtccal = 0;
	226
	227	/*
	228	* Check that the calibration value (which is in units of 0.5
	229	* parts-per-million) is in the AB8500's range for RtcCalibration
	230	* register. -128 (0x80) is not permitted because the AB8500 uses
	231	* a sign-bit rather than two's complement, so 0x80 is just another
	232	* representation of zero.
	233	*/
	234	if ((calibration < -127) \|\| (calibration > 127)) {
	235	dev_err(dev, "RtcCalibration value outside permitted range\n");
	236	return -EINVAL;
	237	}
	238
	239	/*
	240	* The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
	241	* so need to convert to this sort of representation before writing
	242	* into RtcCalibration register...
	243	*/
	244	if (calibration >= 0)
	245	rtccal = 0x7F & calibration;
	246	else
	247	rtccal = ~(calibration - 1) \| 0x80;
	248
	249	retval = abx500_set_register_interruptible(dev, AB8500_RTC,
	250	AB8500_RTC_CALIB_REG, rtccal);
	251
	252	return retval;
	253	}
	254
	255	static int ab8500_rtc_get_calibration(struct device dev, int calibration)
	256	{
	257	int retval;
	258	u8 rtccal = 0;
	259
	260	retval = abx500_get_register_interruptible(dev, AB8500_RTC,
	261	AB8500_RTC_CALIB_REG, &rtccal);
	262	if (retval >= 0) {
	263	/*
	264	* The AB8500 uses sign (in bit7) and magnitude (in bits0-7)
	265	* so need to convert value from RtcCalibration register into
	266	* a two's complement signed value...
	267	*/
	268	if (rtccal & 0x80)
	269	*calibration = 0 - (rtccal & 0x7F);
	270	else
	271	*calibration = 0x7F & rtccal;
	272	}
	273
	274	return retval;
	275	}
	276
	277	static ssize_t ab8500_sysfs_store_rtc_calibration(struct device *dev,
	278	struct device_attribute *attr,
	279	const char *buf, size_t count)
	280	{
	281	int retval;
	282	int calibration = 0;
	283
	284	if (sscanf(buf, " %i ", &calibration) != 1) {
	285	dev_err(dev, "Failed to store RTC calibration attribute\n");
286	return -EINVAL;
287	}
288
289	retval = ab8500_rtc_set_calibration(dev, calibration);
290
291	return retval ? retval : count;
292	}
293
294	static ssize_t ab8500_sysfs_show_rtc_calibration(struct device *dev,
295	struct device_attribute attr, char buf)
296	{
297	int retval = 0;
298	int calibration = 0;
299
300	retval = ab8500_rtc_get_calibration(dev, &calibration);
301	if (retval < 0) {
302	dev_err(dev, "Failed to read RTC calibration attribute\n");
303	sprintf(buf, "0\n");
304	return retval;
305	}
306
307	return sprintf(buf, "%d\n", calibration);
308	}
309
310	static DEVICE_ATTR(rtc_calibration, S_IRUGO \| S_IWUSR,
311	ab8500_sysfs_show_rtc_calibration,
312	ab8500_sysfs_store_rtc_calibration);
313
b56295dd AB	314	static struct attribute *ab8500_rtc_attrs[] = {
	315	&dev_attr_rtc_calibration.attr,
	316	NULL
	317	};
dda367ac	318
b56295dd AB	319	static const struct attribute_group ab8500_rtc_sysfs_files = {
	320	.attrs = ab8500_rtc_attrs,
	321	};
dda367ac	322
0af62f4d VS	323	static irqreturn_t rtc_alarm_handler(int irq, void *data)
	324	{
	325	struct rtc_device *rtc = data;
	326	unsigned long events = RTC_IRQF \| RTC_AF;
	327
	328	dev_dbg(&rtc->dev, "%s\n", __func__);
	329	rtc_update_irq(rtc, 1, events);
	330
	331	return IRQ_HANDLED;
	332	}
	333
	334	static const struct rtc_class_ops ab8500_rtc_ops = {
	335	.read_time = ab8500_rtc_read_time,
	336	.set_time = ab8500_rtc_set_time,
	337	.read_alarm = ab8500_rtc_read_alarm,
	338	.set_alarm = ab8500_rtc_set_alarm,
	339	.alarm_irq_enable = ab8500_rtc_irq_enable,
	340	};
	341
9a72f410	342	static const struct platform_device_id ab85xx_rtc_ids[] = {
25d053cf	343	{ "ab8500-rtc", (kernel_ulong_t)&ab8500_rtc_ops, },
8a67e931	344	{ /* sentinel */ }
25d053cf	345	};
63074cc3	346	MODULE_DEVICE_TABLE(platform, ab85xx_rtc_ids);
25d053cf	347
5a167f45	348	static int ab8500_rtc_probe(struct platform_device *pdev)
0af62f4d	349	{
25d053cf	350	const struct platform_device_id *platid = platform_get_device_id(pdev);
0af62f4d VS	351	int err;
0af62f4d VS	352	struct rtc_device *rtc;
47c16975	353	u8 rtc_ctrl;
0af62f4d VS	354	int irq;
	355
	356	irq = platform_get_irq_byname(pdev, "ALARM");
	357	if (irq < 0)
	358	return irq;
	359
	360	/* For RTC supply test */
47c16975 MW	361	err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC,
47c16975 MW	362	AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA);
0af62f4d VS	363	if (err < 0)
	364	return err;
	365
	366	/* Wait for reset by the PorRtc */
012e52e1	367	usleep_range(1000, 5000);
0af62f4d	368
47c16975 MW	369	err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC,
	370	AB8500_RTC_STAT_REG, &rtc_ctrl);
	371	if (err < 0)
	372	return err;
0af62f4d VS	373
	374	/* Check if the RTC Supply fails */
	375	if (!(rtc_ctrl & RTC_STATUS_DATA)) {
	376	dev_err(&pdev->dev, "RTC supply failure\n");
	377	return -ENODEV;
	378	}
	379
b62581e6 AL	380	device_init_wakeup(&pdev->dev, true);
b62581e6 AL	381
b56295dd AB	382	rtc = devm_rtc_allocate_device(&pdev->dev);
	383	if (IS_ERR(rtc))
	384	return PTR_ERR(rtc);
	385
	386	rtc->ops = (struct rtc_class_ops *)platid->driver_data;
0af62f4d	387
fa11f7e7	388	err = devm_request_threaded_irq(&pdev->dev, irq, NULL,
93a6f916	389	rtc_alarm_handler, IRQF_ONESHOT,
fa11f7e7 JH	390	"ab8500-rtc", rtc);
fa11f7e7 JH	391	if (err < 0)
0af62f4d	392	return err;
0af62f4d	393
93a6f916	394	dev_pm_set_wake_irq(&pdev->dev, irq);
0af62f4d VS	395	platform_set_drvdata(pdev, rtc);
0af62f4d VS	396
c594d678 XP	397	rtc->uie_unsupported = 1;
c594d678 XP	398
38ab97ae AB	399	rtc->range_max = (1ULL << 24) * 60 - 1; // 24-bit minutes + 59 secs
	400	rtc->start_secs = RTC_TIMESTAMP_BEGIN_2000;
	401	rtc->set_start_time = true;
	402
b56295dd AB	403	err = rtc_add_group(rtc, &ab8500_rtc_sysfs_files);
	404	if (err)
	405	return err;
	406
	407	return rtc_register_device(rtc);
0af62f4d VS	408	}
0af62f4d VS	409
5a167f45	410	static int ab8500_rtc_remove(struct platform_device *pdev)
0af62f4d	411	{
93a6f916 SH	412	dev_pm_clear_wake_irq(&pdev->dev);
93a6f916 SH	413	device_init_wakeup(&pdev->dev, false);
dda367ac	414
0af62f4d VS	415	return 0;
	416	}
	417
	418	static struct platform_driver ab8500_rtc_driver = {
	419	.driver = {
	420	.name = "ab8500-rtc",
0af62f4d VS	421	},
0af62f4d VS	422	.probe = ab8500_rtc_probe,
5a167f45	423	.remove = ab8500_rtc_remove,
25d053cf	424	.id_table = ab85xx_rtc_ids,
0af62f4d VS	425	};
0af62f4d VS	426
0c4eae66	427	module_platform_driver(ab8500_rtc_driver);
0af62f4d	428
0af62f4d VS	429	MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>");
	430	MODULE_DESCRIPTION("AB8500 RTC Driver");
	431	MODULE_LICENSE("GPL v2");