[linux.git] / drivers / rtc / rtc-snvs.c

/*
 * Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
 *
 * The code contained herein is licensed under the GNU General Public
 * License. You may obtain a copy of the GNU General Public License
 * Version 2 or later at the following locations:
 *
 * http://www.opensource.org/licenses/gpl-license.html
 * http://www.gnu.org/copyleft/gpl.html
 */

#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/rtc.h>
#include <linux/clk.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>

#define SNVS_LPREGISTER_OFFSET	0x34

/* These register offsets are relative to LP (Low Power) range */
#define SNVS_LPCR		0x04
#define SNVS_LPSR		0x18
#define SNVS_LPSRTCMR		0x1c
#define SNVS_LPSRTCLR		0x20
#define SNVS_LPTAR		0x24
#define SNVS_LPPGDR		0x30

#define SNVS_LPCR_SRTC_ENV	(1 << 0)
#define SNVS_LPCR_LPTA_EN	(1 << 1)
#define SNVS_LPCR_LPWUI_EN	(1 << 3)
#define SNVS_LPSR_LPTA		(1 << 0)

#define SNVS_LPPGDR_INIT	0x41736166
#define CNTR_TO_SECS_SH		15

struct snvs_rtc_data {
	struct rtc_device *rtc;
	struct regmap *regmap;
	int offset;
	int irq;
	struct clk *clk;
};

static u32 rtc_read_lp_counter(struct snvs_rtc_data *data)
{
	u64 read1, read2;
	u32 val;

	do {
		regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &val);
		read1 = val;
		read1 <<= 32;
		regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &val);
		read1 |= val;

		regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &val);
		read2 = val;
		read2 <<= 32;
		regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &val);
		read2 |= val;
	} while (read1 != read2);

	/* Convert 47-bit counter to 32-bit raw second count */
	return (u32) (read1 >> CNTR_TO_SECS_SH);
}

static void rtc_write_sync_lp(struct snvs_rtc_data *data)
{
	u32 count1, count2, count3;
	int i;

	/* Wait for 3 CKIL cycles */
	for (i = 0; i < 3; i++) {
		do {
			regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
			regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count2);
		} while (count1 != count2);

		/* Now wait until counter value changes */
		do {
			do {
				regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count2);
				regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count3);
			} while (count2 != count3);
		} while (count3 == count1);
	}
}

static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable)
{
	int timeout = 1000;
	u32 lpcr;

	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_SRTC_ENV,
			   enable ? SNVS_LPCR_SRTC_ENV : 0);

	while (--timeout) {
		regmap_read(data->regmap, data->offset + SNVS_LPCR, &lpcr);

		if (enable) {
			if (lpcr & SNVS_LPCR_SRTC_ENV)
				break;
		} else {
			if (!(lpcr & SNVS_LPCR_SRTC_ENV))
				break;
		}
	}

	if (!timeout)
		return -ETIMEDOUT;

	return 0;
}

static int snvs_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	unsigned long time = rtc_read_lp_counter(data);

	rtc_time_to_tm(time, tm);

	return 0;
}

static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	unsigned long time;

	rtc_tm_to_time(tm, &time);

	/* Disable RTC first */
	snvs_rtc_enable(data, false);

	/* Write 32-bit time to 47-bit timer, leaving 15 LSBs blank */
	regmap_write(data->regmap, data->offset + SNVS_LPSRTCLR, time << CNTR_TO_SECS_SH);
	regmap_write(data->regmap, data->offset + SNVS_LPSRTCMR, time >> (32 - CNTR_TO_SECS_SH));

	/* Enable RTC again */
	snvs_rtc_enable(data, true);

	return 0;
}

static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	u32 lptar, lpsr;

	regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar);
	rtc_time_to_tm(lptar, &alrm->time);

	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
	alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0;

	return 0;
}

static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);

	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR,
			   (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN),
			   enable ? (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN) : 0);

	rtc_write_sync_lp(data);

	return 0;
}

static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	struct rtc_time *alrm_tm = &alrm->time;
	unsigned long time;

	rtc_tm_to_time(alrm_tm, &time);

	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0);
	regmap_write(data->regmap, data->offset + SNVS_LPTAR, time);

	/* Clear alarm interrupt status bit */
	regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA);

	return snvs_rtc_alarm_irq_enable(dev, alrm->enabled);
}

static const struct rtc_class_ops snvs_rtc_ops = {
	.read_time = snvs_rtc_read_time,
	.set_time = snvs_rtc_set_time,
	.read_alarm = snvs_rtc_read_alarm,
	.set_alarm = snvs_rtc_set_alarm,
	.alarm_irq_enable = snvs_rtc_alarm_irq_enable,
};

static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id)
{
	struct device *dev = dev_id;
	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	u32 lpsr;
	u32 events = 0;

	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);

	if (lpsr & SNVS_LPSR_LPTA) {
		events |= (RTC_AF | RTC_IRQF);

		/* RTC alarm should be one-shot */
		snvs_rtc_alarm_irq_enable(dev, 0);

		rtc_update_irq(data->rtc, 1, events);
	}

	/* clear interrupt status */
	regmap_write(data->regmap, data->offset + SNVS_LPSR, lpsr);

	return events ? IRQ_HANDLED : IRQ_NONE;
}

static const struct regmap_config snvs_rtc_config = {
	.reg_bits = 32,
	.val_bits = 32,
	.reg_stride = 4,
};

static int snvs_rtc_probe(struct platform_device *pdev)
{
	struct snvs_rtc_data *data;
	struct resource *res;
	int ret;
	void __iomem *mmio;

	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");

	if (IS_ERR(data->regmap)) {
		dev_warn(&pdev->dev, "snvs rtc: you use old dts file, please update it\n");
		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

		mmio = devm_ioremap_resource(&pdev->dev, res);
		if (IS_ERR(mmio))
			return PTR_ERR(mmio);

		data->regmap = devm_regmap_init_mmio(&pdev->dev, mmio, &snvs_rtc_config);
	} else {
		data->offset = SNVS_LPREGISTER_OFFSET;
		of_property_read_u32(pdev->dev.of_node, "offset", &data->offset);
	}

	if (!data->regmap) {
		dev_err(&pdev->dev, "Can't find snvs syscon\n");
		return -ENODEV;
	}

	data->irq = platform_get_irq(pdev, 0);
	if (data->irq < 0)
		return data->irq;

	data->clk = devm_clk_get(&pdev->dev, "snvs-rtc");
	if (IS_ERR(data->clk)) {
		data->clk = NULL;
	} else {
		ret = clk_prepare_enable(data->clk);
		if (ret) {
			dev_err(&pdev->dev,
				"Could not prepare or enable the snvs clock\n");
			return ret;
		}
	}

	platform_set_drvdata(pdev, data);

	/* Initialize glitch detect */
	regmap_write(data->regmap, data->offset + SNVS_LPPGDR, SNVS_LPPGDR_INIT);

	/* Clear interrupt status */
	regmap_write(data->regmap, data->offset + SNVS_LPSR, 0xffffffff);

	/* Enable RTC */
	snvs_rtc_enable(data, true);

	device_init_wakeup(&pdev->dev, true);

	ret = devm_request_irq(&pdev->dev, data->irq, snvs_rtc_irq_handler,
			       IRQF_SHARED, "rtc alarm", &pdev->dev);
	if (ret) {
		dev_err(&pdev->dev, "failed to request irq %d: %d\n",
			data->irq, ret);
		goto error_rtc_device_register;
	}

	data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
					&snvs_rtc_ops, THIS_MODULE);
	if (IS_ERR(data->rtc)) {
		ret = PTR_ERR(data->rtc);
		dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
		goto error_rtc_device_register;
	}

	return 0;

error_rtc_device_register:
	if (data->clk)
		clk_disable_unprepare(data->clk);

	return ret;
}

#ifdef CONFIG_PM_SLEEP
static int snvs_rtc_suspend(struct device *dev)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);

	if (device_may_wakeup(dev))
		enable_irq_wake(data->irq);

	return 0;
}

static int snvs_rtc_suspend_noirq(struct device *dev)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);

	if (data->clk)
		clk_disable_unprepare(data->clk);

	return 0;
}

static int snvs_rtc_resume(struct device *dev)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);

	if (device_may_wakeup(dev))
		return disable_irq_wake(data->irq);

	return 0;
}

static int snvs_rtc_resume_noirq(struct device *dev)
{
	struct snvs_rtc_data *data = dev_get_drvdata(dev);

	if (data->clk)
		return clk_prepare_enable(data->clk);

	return 0;
}

static const struct dev_pm_ops snvs_rtc_pm_ops = {
	.suspend = snvs_rtc_suspend,
	.suspend_noirq = snvs_rtc_suspend_noirq,
	.resume = snvs_rtc_resume,
	.resume_noirq = snvs_rtc_resume_noirq,
};

#define SNVS_RTC_PM_OPS	(&snvs_rtc_pm_ops)

#else

#define SNVS_RTC_PM_OPS	NULL

#endif

static const struct of_device_id snvs_dt_ids[] = {
	{ .compatible = "fsl,sec-v4.0-mon-rtc-lp", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, snvs_dt_ids);

static struct platform_driver snvs_rtc_driver = {
	.driver = {
		.name	= "snvs_rtc",
		.pm	= SNVS_RTC_PM_OPS,
		.of_match_table = snvs_dt_ids,
	},
	.probe		= snvs_rtc_probe,
};
module_platform_driver(snvs_rtc_driver);

MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("Freescale SNVS RTC Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
179a502f SG	1	/*
	2	* Copyright (C) 2011-2012 Freescale Semiconductor, Inc.
	3	*
	4	* The code contained herein is licensed under the GNU General Public
	5	* License. You may obtain a copy of the GNU General Public License
	6	* Version 2 or later at the following locations:
	7	*
	8	* http://www.opensource.org/licenses/gpl-license.html
	9	* http://www.gnu.org/copyleft/gpl.html
	10	*/
	11
	12	#include <linux/init.h>
	13	#include <linux/io.h>
	14	#include <linux/kernel.h>
	15	#include <linux/module.h>
	16	#include <linux/of.h>
	17	#include <linux/of_device.h>
	18	#include <linux/platform_device.h>
	19	#include <linux/rtc.h>
7f899399	20	#include <linux/clk.h>
d482893b FL	21	#include <linux/mfd/syscon.h>
	22	#include <linux/regmap.h>
	23
	24	#define SNVS_LPREGISTER_OFFSET 0x34
179a502f SG	25
	26	/* These register offsets are relative to LP (Low Power) range */
	27	#define SNVS_LPCR 0x04
	28	#define SNVS_LPSR 0x18
	29	#define SNVS_LPSRTCMR 0x1c
	30	#define SNVS_LPSRTCLR 0x20
	31	#define SNVS_LPTAR 0x24
	32	#define SNVS_LPPGDR 0x30
	33
	34	#define SNVS_LPCR_SRTC_ENV (1 << 0)
	35	#define SNVS_LPCR_LPTA_EN (1 << 1)
	36	#define SNVS_LPCR_LPWUI_EN (1 << 3)
	37	#define SNVS_LPSR_LPTA (1 << 0)
	38
	39	#define SNVS_LPPGDR_INIT 0x41736166
	40	#define CNTR_TO_SECS_SH 15
	41
	42	struct snvs_rtc_data {
	43	struct rtc_device *rtc;
d482893b FL	44	struct regmap *regmap;
d482893b FL	45	int offset;
179a502f	46	int irq;
7f899399	47	struct clk *clk;
179a502f SG	48	};
179a502f SG	49
d482893b	50	static u32 rtc_read_lp_counter(struct snvs_rtc_data *data)
179a502f SG	51	{
179a502f SG	52	u64 read1, read2;
d482893b	53	u32 val;
179a502f SG	54
179a502f SG	55	do {
d482893b FL	56	regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &val);
d482893b FL	57	read1 = val;
179a502f	58	read1 <<= 32;
d482893b FL	59	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &val);
d482893b FL	60	read1 \|= val;
179a502f	61
d482893b FL	62	regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &val);
d482893b FL	63	read2 = val;
179a502f	64	read2 <<= 32;
d482893b FL	65	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &val);
d482893b FL	66	read2 \|= val;
179a502f SG	67	} while (read1 != read2);
	68
	69	/* Convert 47-bit counter to 32-bit raw second count */
	70	return (u32) (read1 >> CNTR_TO_SECS_SH);
	71	}
	72
d482893b	73	static void rtc_write_sync_lp(struct snvs_rtc_data *data)
179a502f SG	74	{
	75	u32 count1, count2, count3;
	76	int i;
	77
	78	/* Wait for 3 CKIL cycles */
	79	for (i = 0; i < 3; i++) {
	80	do {
d482893b FL	81	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1);
d482893b FL	82	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count2);
179a502f SG	83	} while (count1 != count2);
	84
	85	/* Now wait until counter value changes */
	86	do {
	87	do {
d482893b FL	88	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count2);
d482893b FL	89	regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count3);
179a502f SG	90	} while (count2 != count3);
	91	} while (count3 == count1);
	92	}
	93	}
	94
	95	static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable)
	96	{
179a502f SG	97	int timeout = 1000;
	98	u32 lpcr;
	99
d482893b FL	100	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_SRTC_ENV,
d482893b FL	101	enable ? SNVS_LPCR_SRTC_ENV : 0);
179a502f SG	102
179a502f SG	103	while (--timeout) {
d482893b	104	regmap_read(data->regmap, data->offset + SNVS_LPCR, &lpcr);
179a502f SG	105
	106	if (enable) {
	107	if (lpcr & SNVS_LPCR_SRTC_ENV)
	108	break;
	109	} else {
	110	if (!(lpcr & SNVS_LPCR_SRTC_ENV))
	111	break;
	112	}
	113	}
	114
	115	if (!timeout)
	116	return -ETIMEDOUT;
	117
	118	return 0;
	119	}
	120
	121	static int snvs_rtc_read_time(struct device dev, struct rtc_time tm)
	122	{
	123	struct snvs_rtc_data *data = dev_get_drvdata(dev);
d482893b	124	unsigned long time = rtc_read_lp_counter(data);
179a502f SG	125
	126	rtc_time_to_tm(time, tm);
	127
	128	return 0;
	129	}
	130
	131	static int snvs_rtc_set_time(struct device dev, struct rtc_time tm)
	132	{
	133	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	134	unsigned long time;
	135
	136	rtc_tm_to_time(tm, &time);
	137
	138	/* Disable RTC first */
	139	snvs_rtc_enable(data, false);
	140
	141	/* Write 32-bit time to 47-bit timer, leaving 15 LSBs blank */
d482893b FL	142	regmap_write(data->regmap, data->offset + SNVS_LPSRTCLR, time << CNTR_TO_SECS_SH);
d482893b FL	143	regmap_write(data->regmap, data->offset + SNVS_LPSRTCMR, time >> (32 - CNTR_TO_SECS_SH));
179a502f SG	144
	145	/* Enable RTC again */
	146	snvs_rtc_enable(data, true);
	147
	148	return 0;
	149	}
	150
	151	static int snvs_rtc_read_alarm(struct device dev, struct rtc_wkalrm alrm)
	152	{
	153	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	154	u32 lptar, lpsr;
	155
d482893b	156	regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar);
179a502f SG	157	rtc_time_to_tm(lptar, &alrm->time);
179a502f SG	158
d482893b	159	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
179a502f SG	160	alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0;
	161
	162	return 0;
	163	}
	164
	165	static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable)
	166	{
	167	struct snvs_rtc_data *data = dev_get_drvdata(dev);
179a502f	168
d482893b FL	169	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR,
	170	(SNVS_LPCR_LPTA_EN \| SNVS_LPCR_LPWUI_EN),
	171	enable ? (SNVS_LPCR_LPTA_EN \| SNVS_LPCR_LPWUI_EN) : 0);
179a502f	172
d482893b	173	rtc_write_sync_lp(data);
179a502f SG	174
	175	return 0;
	176	}
	177
	178	static int snvs_rtc_set_alarm(struct device dev, struct rtc_wkalrm alrm)
	179	{
	180	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	181	struct rtc_time *alrm_tm = &alrm->time;
	182	unsigned long time;
179a502f SG	183
	184	rtc_tm_to_time(alrm_tm, &time);
	185
d482893b FL	186	regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0);
d482893b FL	187	regmap_write(data->regmap, data->offset + SNVS_LPTAR, time);
179a502f SG	188
179a502f SG	189	/* Clear alarm interrupt status bit */
d482893b	190	regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA);
179a502f SG	191
	192	return snvs_rtc_alarm_irq_enable(dev, alrm->enabled);
	193	}
	194
	195	static const struct rtc_class_ops snvs_rtc_ops = {
	196	.read_time = snvs_rtc_read_time,
	197	.set_time = snvs_rtc_set_time,
	198	.read_alarm = snvs_rtc_read_alarm,
	199	.set_alarm = snvs_rtc_set_alarm,
	200	.alarm_irq_enable = snvs_rtc_alarm_irq_enable,
	201	};
	202
	203	static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id)
	204	{
	205	struct device *dev = dev_id;
	206	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	207	u32 lpsr;
	208	u32 events = 0;
	209
d482893b	210	regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr);
179a502f SG	211
	212	if (lpsr & SNVS_LPSR_LPTA) {
	213	events \|= (RTC_AF \| RTC_IRQF);
	214
	215	/* RTC alarm should be one-shot */
	216	snvs_rtc_alarm_irq_enable(dev, 0);
	217
	218	rtc_update_irq(data->rtc, 1, events);
	219	}
	220
	221	/* clear interrupt status */
d482893b	222	regmap_write(data->regmap, data->offset + SNVS_LPSR, lpsr);
179a502f SG	223
	224	return events ? IRQ_HANDLED : IRQ_NONE;
	225	}
	226
d482893b FL	227	static const struct regmap_config snvs_rtc_config = {
	228	.reg_bits = 32,
	229	.val_bits = 32,
	230	.reg_stride = 4,
	231	};
	232
5a167f45	233	static int snvs_rtc_probe(struct platform_device *pdev)
179a502f SG	234	{
	235	struct snvs_rtc_data *data;
	236	struct resource *res;
	237	int ret;
d482893b	238	void __iomem *mmio;
179a502f SG	239
	240	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
	241	if (!data)
	242	return -ENOMEM;
	243
d482893b FL	244	data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
	245
	246	if (IS_ERR(data->regmap)) {
	247	dev_warn(&pdev->dev, "snvs rtc: you use old dts file, please update it\n");
	248	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	249
	250	mmio = devm_ioremap_resource(&pdev->dev, res);
	251	if (IS_ERR(mmio))
	252	return PTR_ERR(mmio);
	253
	254	data->regmap = devm_regmap_init_mmio(&pdev->dev, mmio, &snvs_rtc_config);
	255	} else {
	256	data->offset = SNVS_LPREGISTER_OFFSET;
	257	of_property_read_u32(pdev->dev.of_node, "offset", &data->offset);
	258	}
	259
	260	if (!data->regmap) {
	261	dev_err(&pdev->dev, "Can't find snvs syscon\n");
	262	return -ENODEV;
	263	}
179a502f SG	264
	265	data->irq = platform_get_irq(pdev, 0);
	266	if (data->irq < 0)
	267	return data->irq;
	268
7f899399 SM	269	data->clk = devm_clk_get(&pdev->dev, "snvs-rtc");
	270	if (IS_ERR(data->clk)) {
	271	data->clk = NULL;
	272	} else {
	273	ret = clk_prepare_enable(data->clk);
	274	if (ret) {
	275	dev_err(&pdev->dev,
	276	"Could not prepare or enable the snvs clock\n");
	277	return ret;
	278	}
	279	}
	280
179a502f SG	281	platform_set_drvdata(pdev, data);
179a502f SG	282
179a502f	283	/* Initialize glitch detect */
d482893b	284	regmap_write(data->regmap, data->offset + SNVS_LPPGDR, SNVS_LPPGDR_INIT);
179a502f SG	285
179a502f SG	286	/* Clear interrupt status */
d482893b	287	regmap_write(data->regmap, data->offset + SNVS_LPSR, 0xffffffff);
179a502f SG	288
	289	/* Enable RTC */
	290	snvs_rtc_enable(data, true);
	291
	292	device_init_wakeup(&pdev->dev, true);
	293
	294	ret = devm_request_irq(&pdev->dev, data->irq, snvs_rtc_irq_handler,
	295	IRQF_SHARED, "rtc alarm", &pdev->dev);
	296	if (ret) {
	297	dev_err(&pdev->dev, "failed to request irq %d: %d\n",
	298	data->irq, ret);
7f899399	299	goto error_rtc_device_register;
179a502f SG	300	}
179a502f SG	301
904784c1	302	data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
179a502f SG	303	&snvs_rtc_ops, THIS_MODULE);
	304	if (IS_ERR(data->rtc)) {
	305	ret = PTR_ERR(data->rtc);
	306	dev_err(&pdev->dev, "failed to register rtc: %d\n", ret);
7f899399	307	goto error_rtc_device_register;
179a502f SG	308	}
	309
	310	return 0;
7f899399 SM	311
	312	error_rtc_device_register:
	313	if (data->clk)
	314	clk_disable_unprepare(data->clk);
	315
	316	return ret;
179a502f SG	317	}
179a502f SG	318
179a502f SG	319	#ifdef CONFIG_PM_SLEEP
	320	static int snvs_rtc_suspend(struct device *dev)
	321	{
	322	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	323
	324	if (device_may_wakeup(dev))
	325	enable_irq_wake(data->irq);
	326
119434f4 SA	327	return 0;
	328	}
	329
	330	static int snvs_rtc_suspend_noirq(struct device *dev)
	331	{
	332	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	333
7f899399 SM	334	if (data->clk)
	335	clk_disable_unprepare(data->clk);
	336
179a502f SG	337	return 0;
	338	}
	339
	340	static int snvs_rtc_resume(struct device *dev)
	341	{
	342	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	343
	344	if (device_may_wakeup(dev))
119434f4	345	return disable_irq_wake(data->irq);
179a502f	346
119434f4 SA	347	return 0;
	348	}
	349
	350	static int snvs_rtc_resume_noirq(struct device *dev)
	351	{
	352	struct snvs_rtc_data *data = dev_get_drvdata(dev);
	353
	354	if (data->clk)
	355	return clk_prepare_enable(data->clk);
7f899399	356
179a502f SG	357	return 0;
179a502f SG	358	}
179a502f	359
7654e9d4	360	static const struct dev_pm_ops snvs_rtc_pm_ops = {
119434f4 SA	361	.suspend = snvs_rtc_suspend,
	362	.suspend_noirq = snvs_rtc_suspend_noirq,
	363	.resume = snvs_rtc_resume,
	364	.resume_noirq = snvs_rtc_resume_noirq,
7654e9d4	365	};
179a502f	366
88221c32 GR	367	#define SNVS_RTC_PM_OPS (&snvs_rtc_pm_ops)
	368
	369	#else
	370
	371	#define SNVS_RTC_PM_OPS NULL
	372
	373	#endif
	374
5a167f45	375	static const struct of_device_id snvs_dt_ids[] = {
179a502f SG	376	{ .compatible = "fsl,sec-v4.0-mon-rtc-lp", },
	377	{ /* sentinel */ }
	378	};
	379	MODULE_DEVICE_TABLE(of, snvs_dt_ids);
	380
	381	static struct platform_driver snvs_rtc_driver = {
	382	.driver = {
	383	.name = "snvs_rtc",
88221c32	384	.pm = SNVS_RTC_PM_OPS,
c39b3717	385	.of_match_table = snvs_dt_ids,
179a502f SG	386	},
179a502f SG	387	.probe = snvs_rtc_probe,
179a502f SG	388	};
	389	module_platform_driver(snvs_rtc_driver);
	390
	391	MODULE_AUTHOR("Freescale Semiconductor, Inc.");
	392	MODULE_DESCRIPTION("Freescale SNVS RTC Driver");
	393	MODULE_LICENSE("GPL");