[linux-2.6-block.git] / drivers / rtc / rtc-pic32.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * PIC32 RTC driver
 *
 * Joshua Henderson <joshua.henderson@microchip.com>
 * Copyright (C) 2016 Microchip Technology Inc.  All rights reserved.
 *
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/rtc.h>
#include <linux/bcd.h>

#include <asm/mach-pic32/pic32.h>

#define PIC32_RTCCON		0x00
#define PIC32_RTCCON_ON		BIT(15)
#define PIC32_RTCCON_SIDL	BIT(13)
#define PIC32_RTCCON_RTCCLKSEL	(3 << 9)
#define PIC32_RTCCON_RTCCLKON	BIT(6)
#define PIC32_RTCCON_RTCWREN	BIT(3)
#define PIC32_RTCCON_RTCSYNC	BIT(2)
#define PIC32_RTCCON_HALFSEC	BIT(1)
#define PIC32_RTCCON_RTCOE	BIT(0)

#define PIC32_RTCALRM		0x10
#define PIC32_RTCALRM_ALRMEN	BIT(15)
#define PIC32_RTCALRM_CHIME	BIT(14)
#define PIC32_RTCALRM_PIV	BIT(13)
#define PIC32_RTCALRM_ALARMSYNC	BIT(12)
#define PIC32_RTCALRM_AMASK	0x0F00
#define PIC32_RTCALRM_ARPT	0xFF

#define PIC32_RTCHOUR		0x23
#define PIC32_RTCMIN		0x22
#define PIC32_RTCSEC		0x21
#define PIC32_RTCYEAR		0x33
#define PIC32_RTCMON		0x32
#define PIC32_RTCDAY		0x31

#define PIC32_ALRMTIME		0x40
#define PIC32_ALRMDATE		0x50

#define PIC32_ALRMHOUR		0x43
#define PIC32_ALRMMIN		0x42
#define PIC32_ALRMSEC		0x41
#define PIC32_ALRMYEAR		0x53
#define PIC32_ALRMMON		0x52
#define PIC32_ALRMDAY		0x51

struct pic32_rtc_dev {
	struct rtc_device	*rtc;
	void __iomem		*reg_base;
	struct clk		*clk;
	spinlock_t		alarm_lock;
	int			alarm_irq;
	bool			alarm_clk_enabled;
};

static void pic32_rtc_alarm_clk_enable(struct pic32_rtc_dev *pdata,
				       bool enable)
{
	unsigned long flags;

	spin_lock_irqsave(&pdata->alarm_lock, flags);
	if (enable) {
		if (!pdata->alarm_clk_enabled) {
			clk_enable(pdata->clk);
			pdata->alarm_clk_enabled = true;
		}
	} else {
		if (pdata->alarm_clk_enabled) {
			clk_disable(pdata->clk);
			pdata->alarm_clk_enabled = false;
		}
	}
	spin_unlock_irqrestore(&pdata->alarm_lock, flags);
}

static irqreturn_t pic32_rtc_alarmirq(int irq, void *id)
{
	struct pic32_rtc_dev *pdata = (struct pic32_rtc_dev *)id;

	clk_enable(pdata->clk);
	rtc_update_irq(pdata->rtc, 1, RTC_AF | RTC_IRQF);
	clk_disable(pdata->clk);

	pic32_rtc_alarm_clk_enable(pdata, false);

	return IRQ_HANDLED;
}

static int pic32_rtc_setaie(struct device *dev, unsigned int enabled)
{
	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	void __iomem *base = pdata->reg_base;

	clk_enable(pdata->clk);

	writel(PIC32_RTCALRM_ALRMEN,
	       base + (enabled ? PIC32_SET(PIC32_RTCALRM) :
		       PIC32_CLR(PIC32_RTCALRM)));

	clk_disable(pdata->clk);

	pic32_rtc_alarm_clk_enable(pdata, enabled);

	return 0;
}

static int pic32_rtc_setfreq(struct device *dev, int freq)
{
	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	void __iomem *base = pdata->reg_base;

	clk_enable(pdata->clk);

	writel(PIC32_RTCALRM_AMASK, base + PIC32_CLR(PIC32_RTCALRM));
	writel(freq << 8, base + PIC32_SET(PIC32_RTCALRM));
	writel(PIC32_RTCALRM_CHIME, base + PIC32_SET(PIC32_RTCALRM));

	clk_disable(pdata->clk);

	return 0;
}

static int pic32_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm)
{
	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	void __iomem *base = pdata->reg_base;
	unsigned int tries = 0;

	clk_enable(pdata->clk);

	do {
		rtc_tm->tm_hour = readb(base + PIC32_RTCHOUR);
		rtc_tm->tm_min = readb(base + PIC32_RTCMIN);
		rtc_tm->tm_mon  = readb(base + PIC32_RTCMON);
		rtc_tm->tm_mday = readb(base + PIC32_RTCDAY);
		rtc_tm->tm_year = readb(base + PIC32_RTCYEAR);
		rtc_tm->tm_sec  = readb(base + PIC32_RTCSEC);

		/*
		 * The only way to work out whether the system was mid-update
		 * when we read it is to check the second counter, and if it
		 * is zero, then we re-try the entire read.
		 */
		tries += 1;
	} while (rtc_tm->tm_sec == 0 && tries < 2);

	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon) - 1;
	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);

	rtc_tm->tm_year += 100;

	dev_dbg(dev, "read time %ptR\n", rtc_tm);

	clk_disable(pdata->clk);
	return 0;
}

static int pic32_rtc_settime(struct device *dev, struct rtc_time *tm)
{
	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	void __iomem *base = pdata->reg_base;

	dev_dbg(dev, "set time %ptR\n", tm);

	clk_enable(pdata->clk);
	writeb(bin2bcd(tm->tm_sec),  base + PIC32_RTCSEC);
	writeb(bin2bcd(tm->tm_min),  base + PIC32_RTCMIN);
	writeb(bin2bcd(tm->tm_hour), base + PIC32_RTCHOUR);
	writeb(bin2bcd(tm->tm_mday), base + PIC32_RTCDAY);
	writeb(bin2bcd(tm->tm_mon + 1), base + PIC32_RTCMON);
	writeb(bin2bcd(tm->tm_year - 100), base + PIC32_RTCYEAR);
	clk_disable(pdata->clk);

	return 0;
}

static int pic32_rtc_getalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	struct rtc_time *alm_tm = &alrm->time;
	void __iomem *base = pdata->reg_base;
	unsigned int alm_en;

	clk_enable(pdata->clk);
	alm_tm->tm_sec  = readb(base + PIC32_ALRMSEC);
	alm_tm->tm_min  = readb(base + PIC32_ALRMMIN);
	alm_tm->tm_hour = readb(base + PIC32_ALRMHOUR);
	alm_tm->tm_mon  = readb(base + PIC32_ALRMMON);
	alm_tm->tm_mday = readb(base + PIC32_ALRMDAY);
	alm_tm->tm_year = readb(base + PIC32_ALRMYEAR);

	alm_en = readb(base + PIC32_RTCALRM);

	alrm->enabled = (alm_en & PIC32_RTCALRM_ALRMEN) ? 1 : 0;

	dev_dbg(dev, "getalarm: %d, %ptR\n", alm_en, alm_tm);

	alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
	alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
	alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
	alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
	alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon) - 1;
	alm_tm->tm_year = bcd2bin(alm_tm->tm_year);

	clk_disable(pdata->clk);
	return 0;
}

static int pic32_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	struct rtc_time *tm = &alrm->time;
	void __iomem *base = pdata->reg_base;

	clk_enable(pdata->clk);
	dev_dbg(dev, "setalarm: %d, %ptR\n", alrm->enabled, tm);

	writel(0x00, base + PIC32_ALRMTIME);
	writel(0x00, base + PIC32_ALRMDATE);

	pic32_rtc_setaie(dev, alrm->enabled);

	clk_disable(pdata->clk);
	return 0;
}

static int pic32_rtc_proc(struct device *dev, struct seq_file *seq)
{
	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	void __iomem *base = pdata->reg_base;
	unsigned int repeat;

	clk_enable(pdata->clk);

	repeat = readw(base + PIC32_RTCALRM);
	repeat &= PIC32_RTCALRM_ARPT;
	seq_printf(seq, "periodic_IRQ\t: %s\n", repeat  ? "yes" : "no");

	clk_disable(pdata->clk);
	return 0;
}

static const struct rtc_class_ops pic32_rtcops = {
	.read_time	  = pic32_rtc_gettime,
	.set_time	  = pic32_rtc_settime,
	.read_alarm	  = pic32_rtc_getalarm,
	.set_alarm	  = pic32_rtc_setalarm,
	.proc		  = pic32_rtc_proc,
	.alarm_irq_enable = pic32_rtc_setaie,
};

static void pic32_rtc_enable(struct pic32_rtc_dev *pdata, int en)
{
	void __iomem *base = pdata->reg_base;

	if (!base)
		return;

	clk_enable(pdata->clk);
	if (!en) {
		writel(PIC32_RTCCON_ON, base + PIC32_CLR(PIC32_RTCCON));
	} else {
		pic32_syskey_unlock();

		writel(PIC32_RTCCON_RTCWREN, base + PIC32_SET(PIC32_RTCCON));
		writel(3 << 9, base + PIC32_CLR(PIC32_RTCCON));

		if (!(readl(base + PIC32_RTCCON) & PIC32_RTCCON_ON))
			writel(PIC32_RTCCON_ON, base + PIC32_SET(PIC32_RTCCON));
	}
	clk_disable(pdata->clk);
}

static int pic32_rtc_remove(struct platform_device *pdev)
{
	struct pic32_rtc_dev *pdata = platform_get_drvdata(pdev);

	pic32_rtc_setaie(&pdev->dev, 0);
	clk_unprepare(pdata->clk);
	pdata->clk = NULL;

	return 0;
}

static int pic32_rtc_probe(struct platform_device *pdev)
{
	struct pic32_rtc_dev *pdata;
	struct resource *res;
	int ret;

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

	platform_set_drvdata(pdev, pdata);

	pdata->alarm_irq = platform_get_irq(pdev, 0);
	if (pdata->alarm_irq < 0) {
		dev_err(&pdev->dev, "no irq for alarm\n");
		return pdata->alarm_irq;
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	pdata->reg_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(pdata->reg_base))
		return PTR_ERR(pdata->reg_base);

	pdata->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(pdata->clk)) {
		dev_err(&pdev->dev, "failed to find rtc clock source\n");
		ret = PTR_ERR(pdata->clk);
		pdata->clk = NULL;
		return ret;
	}

	spin_lock_init(&pdata->alarm_lock);

	clk_prepare_enable(pdata->clk);

	pic32_rtc_enable(pdata, 1);

	device_init_wakeup(&pdev->dev, 1);

	pdata->rtc = devm_rtc_allocate_device(&pdev->dev);
	if (IS_ERR(pdata->rtc))
		return PTR_ERR(pdata->rtc);

	pdata->rtc->ops = &pic32_rtcops;
	pdata->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
	pdata->rtc->range_max = RTC_TIMESTAMP_END_2099;

	ret = rtc_register_device(pdata->rtc);
	if (ret)
		goto err_nortc;

	pdata->rtc->max_user_freq = 128;

	pic32_rtc_setfreq(&pdev->dev, 1);
	ret = devm_request_irq(&pdev->dev, pdata->alarm_irq,
			       pic32_rtc_alarmirq, 0,
			       dev_name(&pdev->dev), pdata);
	if (ret) {
		dev_err(&pdev->dev,
			"IRQ %d error %d\n", pdata->alarm_irq, ret);
		goto err_nortc;
	}

	clk_disable(pdata->clk);

	return 0;

err_nortc:
	pic32_rtc_enable(pdata, 0);
	clk_disable_unprepare(pdata->clk);

	return ret;
}

static const struct of_device_id pic32_rtc_dt_ids[] = {
	{ .compatible = "microchip,pic32mzda-rtc" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, pic32_rtc_dt_ids);

static struct platform_driver pic32_rtc_driver = {
	.probe		= pic32_rtc_probe,
	.remove		= pic32_rtc_remove,
	.driver		= {
		.name	= "pic32-rtc",
		.of_match_table	= of_match_ptr(pic32_rtc_dt_ids),
	},
};
module_platform_driver(pic32_rtc_driver);

MODULE_DESCRIPTION("Microchip PIC32 RTC Driver");
MODULE_AUTHOR("Joshua Henderson <joshua.henderson@microchip.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
e91b94fd	1	// SPDX-License-Identifier: GPL-2.0+
51aa905c JH	2	/*
	3	* PIC32 RTC driver
	4	*
	5	* Joshua Henderson <joshua.henderson@microchip.com>
	6	* Copyright (C) 2016 Microchip Technology Inc. All rights reserved.
	7	*
51aa905c JH	8	*/
	9	#include <linux/init.h>
	10	#include <linux/module.h>
	11	#include <linux/of.h>
	12	#include <linux/platform_device.h>
	13	#include <linux/io.h>
	14	#include <linux/slab.h>
	15	#include <linux/clk.h>
	16	#include <linux/rtc.h>
	17	#include <linux/bcd.h>
	18
	19	#include <asm/mach-pic32/pic32.h>
	20
	21	#define PIC32_RTCCON 0x00
	22	#define PIC32_RTCCON_ON BIT(15)
	23	#define PIC32_RTCCON_SIDL BIT(13)
	24	#define PIC32_RTCCON_RTCCLKSEL (3 << 9)
	25	#define PIC32_RTCCON_RTCCLKON BIT(6)
	26	#define PIC32_RTCCON_RTCWREN BIT(3)
	27	#define PIC32_RTCCON_RTCSYNC BIT(2)
	28	#define PIC32_RTCCON_HALFSEC BIT(1)
	29	#define PIC32_RTCCON_RTCOE BIT(0)
	30
	31	#define PIC32_RTCALRM 0x10
	32	#define PIC32_RTCALRM_ALRMEN BIT(15)
	33	#define PIC32_RTCALRM_CHIME BIT(14)
	34	#define PIC32_RTCALRM_PIV BIT(13)
	35	#define PIC32_RTCALRM_ALARMSYNC BIT(12)
	36	#define PIC32_RTCALRM_AMASK 0x0F00
	37	#define PIC32_RTCALRM_ARPT 0xFF
	38
	39	#define PIC32_RTCHOUR 0x23
	40	#define PIC32_RTCMIN 0x22
	41	#define PIC32_RTCSEC 0x21
	42	#define PIC32_RTCYEAR 0x33
	43	#define PIC32_RTCMON 0x32
	44	#define PIC32_RTCDAY 0x31
	45
	46	#define PIC32_ALRMTIME 0x40
	47	#define PIC32_ALRMDATE 0x50
	48
	49	#define PIC32_ALRMHOUR 0x43
	50	#define PIC32_ALRMMIN 0x42
	51	#define PIC32_ALRMSEC 0x41
	52	#define PIC32_ALRMYEAR 0x53
	53	#define PIC32_ALRMMON 0x52
	54	#define PIC32_ALRMDAY 0x51
	55
	56	struct pic32_rtc_dev {
	57	struct rtc_device *rtc;
	58	void __iomem *reg_base;
	59	struct clk *clk;
	60	spinlock_t alarm_lock;
	61	int alarm_irq;
	62	bool alarm_clk_enabled;
	63	};
	64
	65	static void pic32_rtc_alarm_clk_enable(struct pic32_rtc_dev *pdata,
	66	bool enable)
	67	{
	68	unsigned long flags;
	69
	70	spin_lock_irqsave(&pdata->alarm_lock, flags);
	71	if (enable) {
72	if (!pdata->alarm_clk_enabled) {
73	clk_enable(pdata->clk);
74	pdata->alarm_clk_enabled = true;
75	}
76	} else {
77	if (pdata->alarm_clk_enabled) {
78	clk_disable(pdata->clk);
79	pdata->alarm_clk_enabled = false;
80	}
81	}
82	spin_unlock_irqrestore(&pdata->alarm_lock, flags);
83	}
84
85	static irqreturn_t pic32_rtc_alarmirq(int irq, void *id)
86	{
87	struct pic32_rtc_dev pdata = (struct pic32_rtc_dev )id;
88
89	clk_enable(pdata->clk);
90	rtc_update_irq(pdata->rtc, 1, RTC_AF \| RTC_IRQF);
91	clk_disable(pdata->clk);
92
93	pic32_rtc_alarm_clk_enable(pdata, false);
94
95	return IRQ_HANDLED;
96	}
97
98	static int pic32_rtc_setaie(struct device *dev, unsigned int enabled)
99	{
100	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
101	void __iomem *base = pdata->reg_base;
102
103	clk_enable(pdata->clk);
104
105	writel(PIC32_RTCALRM_ALRMEN,
106	base + (enabled ? PIC32_SET(PIC32_RTCALRM) :
107	PIC32_CLR(PIC32_RTCALRM)));
108
109	clk_disable(pdata->clk);
110
111	pic32_rtc_alarm_clk_enable(pdata, enabled);
112
113	return 0;
114	}
115
116	static int pic32_rtc_setfreq(struct device *dev, int freq)
117	{
118	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
119	void __iomem *base = pdata->reg_base;
120
121	clk_enable(pdata->clk);
122
123	writel(PIC32_RTCALRM_AMASK, base + PIC32_CLR(PIC32_RTCALRM));
124	writel(freq << 8, base + PIC32_SET(PIC32_RTCALRM));
125	writel(PIC32_RTCALRM_CHIME, base + PIC32_SET(PIC32_RTCALRM));
126
127	clk_disable(pdata->clk);
128
129	return 0;
130	}
131
132	static int pic32_rtc_gettime(struct device dev, struct rtc_time rtc_tm)
133	{
134	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
135	void __iomem *base = pdata->reg_base;
136	unsigned int tries = 0;
137
138	clk_enable(pdata->clk);
139
140	do {
141	rtc_tm->tm_hour = readb(base + PIC32_RTCHOUR);
142	rtc_tm->tm_min = readb(base + PIC32_RTCMIN);
143	rtc_tm->tm_mon = readb(base + PIC32_RTCMON);
144	rtc_tm->tm_mday = readb(base + PIC32_RTCDAY);
145	rtc_tm->tm_year = readb(base + PIC32_RTCYEAR);
146	rtc_tm->tm_sec = readb(base + PIC32_RTCSEC);
147
148	/*
149	* The only way to work out whether the system was mid-update
150	* when we read it is to check the second counter, and if it
151	* is zero, then we re-try the entire read.
152	*/
153	tries += 1;
154	} while (rtc_tm->tm_sec == 0 && tries < 2);
155
156	rtc_tm->tm_sec = bcd2bin(rtc_tm->tm_sec);
157	rtc_tm->tm_min = bcd2bin(rtc_tm->tm_min);
158	rtc_tm->tm_hour = bcd2bin(rtc_tm->tm_hour);
159	rtc_tm->tm_mday = bcd2bin(rtc_tm->tm_mday);
160	rtc_tm->tm_mon = bcd2bin(rtc_tm->tm_mon) - 1;
161	rtc_tm->tm_year = bcd2bin(rtc_tm->tm_year);
162
163	rtc_tm->tm_year += 100;
164
93206f93	165	dev_dbg(dev, "read time %ptR\n", rtc_tm);
51aa905c JH	166
51aa905c JH	167	clk_disable(pdata->clk);
22652ba7	168	return 0;
51aa905c JH	169	}
	170
	171	static int pic32_rtc_settime(struct device dev, struct rtc_time tm)
	172	{
	173	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	174	void __iomem *base = pdata->reg_base;
51aa905c	175
93206f93	176	dev_dbg(dev, "set time %ptR\n", tm);
51aa905c	177
51aa905c JH	178	clk_enable(pdata->clk);
	179	writeb(bin2bcd(tm->tm_sec), base + PIC32_RTCSEC);
	180	writeb(bin2bcd(tm->tm_min), base + PIC32_RTCMIN);
	181	writeb(bin2bcd(tm->tm_hour), base + PIC32_RTCHOUR);
	182	writeb(bin2bcd(tm->tm_mday), base + PIC32_RTCDAY);
	183	writeb(bin2bcd(tm->tm_mon + 1), base + PIC32_RTCMON);
c145e5f4	184	writeb(bin2bcd(tm->tm_year - 100), base + PIC32_RTCYEAR);
51aa905c JH	185	clk_disable(pdata->clk);
	186
	187	return 0;
	188	}
	189
	190	static int pic32_rtc_getalarm(struct device dev, struct rtc_wkalrm alrm)
	191	{
	192	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	193	struct rtc_time *alm_tm = &alrm->time;
	194	void __iomem *base = pdata->reg_base;
	195	unsigned int alm_en;
	196
	197	clk_enable(pdata->clk);
	198	alm_tm->tm_sec = readb(base + PIC32_ALRMSEC);
	199	alm_tm->tm_min = readb(base + PIC32_ALRMMIN);
	200	alm_tm->tm_hour = readb(base + PIC32_ALRMHOUR);
	201	alm_tm->tm_mon = readb(base + PIC32_ALRMMON);
	202	alm_tm->tm_mday = readb(base + PIC32_ALRMDAY);
	203	alm_tm->tm_year = readb(base + PIC32_ALRMYEAR);
	204
	205	alm_en = readb(base + PIC32_RTCALRM);
	206
	207	alrm->enabled = (alm_en & PIC32_RTCALRM_ALRMEN) ? 1 : 0;
	208
93206f93	209	dev_dbg(dev, "getalarm: %d, %ptR\n", alm_en, alm_tm);
51aa905c JH	210
	211	alm_tm->tm_sec = bcd2bin(alm_tm->tm_sec);
	212	alm_tm->tm_min = bcd2bin(alm_tm->tm_min);
	213	alm_tm->tm_hour = bcd2bin(alm_tm->tm_hour);
	214	alm_tm->tm_mday = bcd2bin(alm_tm->tm_mday);
	215	alm_tm->tm_mon = bcd2bin(alm_tm->tm_mon) - 1;
	216	alm_tm->tm_year = bcd2bin(alm_tm->tm_year);
	217
	218	clk_disable(pdata->clk);
	219	return 0;
	220	}
	221
	222	static int pic32_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
	223	{
	224	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	225	struct rtc_time *tm = &alrm->time;
	226	void __iomem *base = pdata->reg_base;
	227
	228	clk_enable(pdata->clk);
93206f93	229	dev_dbg(dev, "setalarm: %d, %ptR\n", alrm->enabled, tm);
51aa905c JH	230
	231	writel(0x00, base + PIC32_ALRMTIME);
	232	writel(0x00, base + PIC32_ALRMDATE);
	233
	234	pic32_rtc_setaie(dev, alrm->enabled);
	235
	236	clk_disable(pdata->clk);
	237	return 0;
	238	}
	239
	240	static int pic32_rtc_proc(struct device dev, struct seq_file seq)
	241	{
	242	struct pic32_rtc_dev *pdata = dev_get_drvdata(dev);
	243	void __iomem *base = pdata->reg_base;
	244	unsigned int repeat;
	245
	246	clk_enable(pdata->clk);
	247
	248	repeat = readw(base + PIC32_RTCALRM);
	249	repeat &= PIC32_RTCALRM_ARPT;
	250	seq_printf(seq, "periodic_IRQ\t: %s\n", repeat ? "yes" : "no");
	251
	252	clk_disable(pdata->clk);
	253	return 0;
	254	}
	255
	256	static const struct rtc_class_ops pic32_rtcops = {
	257	.read_time = pic32_rtc_gettime,
	258	.set_time = pic32_rtc_settime,
	259	.read_alarm = pic32_rtc_getalarm,
	260	.set_alarm = pic32_rtc_setalarm,
	261	.proc = pic32_rtc_proc,
	262	.alarm_irq_enable = pic32_rtc_setaie,
	263	};
	264
	265	static void pic32_rtc_enable(struct pic32_rtc_dev *pdata, int en)
	266	{
	267	void __iomem *base = pdata->reg_base;
	268
	269	if (!base)
	270	return;
	271
	272	clk_enable(pdata->clk);
	273	if (!en) {
	274	writel(PIC32_RTCCON_ON, base + PIC32_CLR(PIC32_RTCCON));
	275	} else {
	276	pic32_syskey_unlock();
	277
	278	writel(PIC32_RTCCON_RTCWREN, base + PIC32_SET(PIC32_RTCCON));
	279	writel(3 << 9, base + PIC32_CLR(PIC32_RTCCON));
	280
	281	if (!(readl(base + PIC32_RTCCON) & PIC32_RTCCON_ON))
	282	writel(PIC32_RTCCON_ON, base + PIC32_SET(PIC32_RTCCON));
	283	}
	284	clk_disable(pdata->clk);
	285	}
	286
	287	static int pic32_rtc_remove(struct platform_device *pdev)
	288	{
	289	struct pic32_rtc_dev *pdata = platform_get_drvdata(pdev);
	290
	291	pic32_rtc_setaie(&pdev->dev, 0);
	292	clk_unprepare(pdata->clk);
	293	pdata->clk = NULL;
294
295	return 0;
296	}
297
298	static int pic32_rtc_probe(struct platform_device *pdev)
299	{
300	struct pic32_rtc_dev *pdata;
301	struct resource *res;
302	int ret;
303
304	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
305	if (!pdata)
306	return -ENOMEM;
307
308	platform_set_drvdata(pdev, pdata);
309
310	pdata->alarm_irq = platform_get_irq(pdev, 0);
311	if (pdata->alarm_irq < 0) {
312	dev_err(&pdev->dev, "no irq for alarm\n");
313	return pdata->alarm_irq;
314	}
315
316	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
317	pdata->reg_base = devm_ioremap_resource(&pdev->dev, res);
318	if (IS_ERR(pdata->reg_base))
319	return PTR_ERR(pdata->reg_base);
320
321	pdata->clk = devm_clk_get(&pdev->dev, NULL);
322	if (IS_ERR(pdata->clk)) {
323	dev_err(&pdev->dev, "failed to find rtc clock source\n");
324	ret = PTR_ERR(pdata->clk);
325	pdata->clk = NULL;
326	return ret;
327	}
328
329	spin_lock_init(&pdata->alarm_lock);
330
331	clk_prepare_enable(pdata->clk);
332
333	pic32_rtc_enable(pdata, 1);
334
335	device_init_wakeup(&pdev->dev, 1);
336
6515e23b AB	337	pdata->rtc = devm_rtc_allocate_device(&pdev->dev);
	338	if (IS_ERR(pdata->rtc))
	339	return PTR_ERR(pdata->rtc);
	340
	341	pdata->rtc->ops = &pic32_rtcops;
c145e5f4 AB	342	pdata->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
c145e5f4 AB	343	pdata->rtc->range_max = RTC_TIMESTAMP_END_2099;
6515e23b AB	344
	345	ret = rtc_register_device(pdata->rtc);
	346	if (ret)
51aa905c	347	goto err_nortc;
51aa905c JH	348
	349	pdata->rtc->max_user_freq = 128;
	350
	351	pic32_rtc_setfreq(&pdev->dev, 1);
	352	ret = devm_request_irq(&pdev->dev, pdata->alarm_irq,
	353	pic32_rtc_alarmirq, 0,
	354	dev_name(&pdev->dev), pdata);
	355	if (ret) {
	356	dev_err(&pdev->dev,
	357	"IRQ %d error %d\n", pdata->alarm_irq, ret);
	358	goto err_nortc;
	359	}
	360
	361	clk_disable(pdata->clk);
	362
	363	return 0;
	364
	365	err_nortc:
	366	pic32_rtc_enable(pdata, 0);
	367	clk_disable_unprepare(pdata->clk);
	368
	369	return ret;
	370	}
	371
	372	static const struct of_device_id pic32_rtc_dt_ids[] = {
	373	{ .compatible = "microchip,pic32mzda-rtc" },
	374	{ /* sentinel */ }
	375	};
	376	MODULE_DEVICE_TABLE(of, pic32_rtc_dt_ids);
	377
	378	static struct platform_driver pic32_rtc_driver = {
	379	.probe = pic32_rtc_probe,
	380	.remove = pic32_rtc_remove,
	381	.driver = {
	382	.name = "pic32-rtc",
51aa905c JH	383	.of_match_table = of_match_ptr(pic32_rtc_dt_ids),
	384	},
	385	};
	386	module_platform_driver(pic32_rtc_driver);
	387
	388	MODULE_DESCRIPTION("Microchip PIC32 RTC Driver");
	389	MODULE_AUTHOR("Joshua Henderson <joshua.henderson@microchip.com>");
	390	MODULE_LICENSE("GPL");