[linux-2.6-block.git] / drivers / rtc / rtc-pl030.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/drivers/rtc/rtc-pl030.c
 *
 *  Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
 */
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/amba/bus.h>
#include <linux/io.h>
#include <linux/slab.h>

#define RTC_DR		(0)
#define RTC_MR		(4)
#define RTC_STAT	(8)
#define RTC_EOI		(8)
#define RTC_LR		(12)
#define RTC_CR		(16)
#define RTC_CR_MIE	(1 << 0)

struct pl030_rtc {
	struct rtc_device	*rtc;
	void __iomem		*base;
};

static irqreturn_t pl030_interrupt(int irq, void *dev_id)
{
	struct pl030_rtc *rtc = dev_id;
	writel(0, rtc->base + RTC_EOI);
	return IRQ_HANDLED;
}

static int pl030_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pl030_rtc *rtc = dev_get_drvdata(dev);

	rtc_time_to_tm(readl(rtc->base + RTC_MR), &alrm->time);
	return 0;
}

static int pl030_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct pl030_rtc *rtc = dev_get_drvdata(dev);
	unsigned long time;
	int ret;

	/*
	 * At the moment, we can only deal with non-wildcarded alarm times.
	 */
	ret = rtc_valid_tm(&alrm->time);
	if (ret == 0)
		ret = rtc_tm_to_time(&alrm->time, &time);
	if (ret == 0)
		writel(time, rtc->base + RTC_MR);
	return ret;
}

static int pl030_read_time(struct device *dev, struct rtc_time *tm)
{
	struct pl030_rtc *rtc = dev_get_drvdata(dev);

	rtc_time_to_tm(readl(rtc->base + RTC_DR), tm);

	return 0;
}

/*
 * Set the RTC time.  Unfortunately, we can't accurately set
 * the point at which the counter updates.
 *
 * Also, since RTC_LR is transferred to RTC_CR on next rising
 * edge of the 1Hz clock, we must write the time one second
 * in advance.
 */
static int pl030_set_time(struct device *dev, struct rtc_time *tm)
{
	struct pl030_rtc *rtc = dev_get_drvdata(dev);
	unsigned long time;
	int ret;

	ret = rtc_tm_to_time(tm, &time);
	if (ret == 0)
		writel(time + 1, rtc->base + RTC_LR);

	return ret;
}

static const struct rtc_class_ops pl030_ops = {
	.read_time	= pl030_read_time,
	.set_time	= pl030_set_time,
	.read_alarm	= pl030_read_alarm,
	.set_alarm	= pl030_set_alarm,
};

static int pl030_probe(struct amba_device *dev, const struct amba_id *id)
{
	struct pl030_rtc *rtc;
	int ret;

	ret = amba_request_regions(dev, NULL);
	if (ret)
		goto err_req;

	rtc = devm_kzalloc(&dev->dev, sizeof(*rtc), GFP_KERNEL);
	if (!rtc) {
		ret = -ENOMEM;
		goto err_rtc;
	}

	rtc->rtc = devm_rtc_allocate_device(&dev->dev);
	if (IS_ERR(rtc->rtc)) {
		ret = PTR_ERR(rtc->rtc);
		goto err_rtc;
	}

	rtc->rtc->ops = &pl030_ops;
	rtc->base = ioremap(dev->res.start, resource_size(&dev->res));
	if (!rtc->base) {
		ret = -ENOMEM;
		goto err_rtc;
	}

	__raw_writel(0, rtc->base + RTC_CR);
	__raw_writel(0, rtc->base + RTC_EOI);

	amba_set_drvdata(dev, rtc);

	ret = request_irq(dev->irq[0], pl030_interrupt, 0,
			  "rtc-pl030", rtc);
	if (ret)
		goto err_irq;

	ret = rtc_register_device(rtc->rtc);
	if (ret)
		goto err_reg;

	return 0;

 err_reg:
	free_irq(dev->irq[0], rtc);
 err_irq:
	iounmap(rtc->base);
 err_rtc:
	amba_release_regions(dev);
 err_req:
	return ret;
}

static int pl030_remove(struct amba_device *dev)
{
	struct pl030_rtc *rtc = amba_get_drvdata(dev);

	writel(0, rtc->base + RTC_CR);

	free_irq(dev->irq[0], rtc);
	iounmap(rtc->base);
	amba_release_regions(dev);

	return 0;
}

static struct amba_id pl030_ids[] = {
	{
		.id	= 0x00041030,
		.mask	= 0x000fffff,
	},
	{ 0, 0 },
};

MODULE_DEVICE_TABLE(amba, pl030_ids);

static struct amba_driver pl030_driver = {
	.drv		= {
		.name	= "rtc-pl030",
	},
	.probe		= pl030_probe,
	.remove		= pl030_remove,
	.id_table	= pl030_ids,
};

module_amba_driver(pl030_driver);

MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
MODULE_DESCRIPTION("ARM AMBA PL030 RTC Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
a190901c RK	2	/*
	3	* linux/drivers/rtc/rtc-pl030.c
	4	*
	5	* Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
a190901c RK	6	*/
	7	#include <linux/module.h>
	8	#include <linux/rtc.h>
	9	#include <linux/init.h>
	10	#include <linux/interrupt.h>
	11	#include <linux/amba/bus.h>
	12	#include <linux/io.h>
5a0e3ad6	13	#include <linux/slab.h>
a190901c RK	14
	15	#define RTC_DR (0)
	16	#define RTC_MR (4)
	17	#define RTC_STAT (8)
	18	#define RTC_EOI (8)
	19	#define RTC_LR (12)
	20	#define RTC_CR (16)
	21	#define RTC_CR_MIE (1 << 0)
	22
	23	struct pl030_rtc {
	24	struct rtc_device *rtc;
	25	void __iomem *base;
	26	};
	27
	28	static irqreturn_t pl030_interrupt(int irq, void *dev_id)
	29	{
	30	struct pl030_rtc *rtc = dev_id;
	31	writel(0, rtc->base + RTC_EOI);
	32	return IRQ_HANDLED;
	33	}
	34
a190901c RK	35	static int pl030_read_alarm(struct device dev, struct rtc_wkalrm alrm)
	36	{
	37	struct pl030_rtc *rtc = dev_get_drvdata(dev);
	38
	39	rtc_time_to_tm(readl(rtc->base + RTC_MR), &alrm->time);
	40	return 0;
	41	}
	42
	43	static int pl030_set_alarm(struct device dev, struct rtc_wkalrm alrm)
	44	{
	45	struct pl030_rtc *rtc = dev_get_drvdata(dev);
	46	unsigned long time;
	47	int ret;
	48
	49	/*
	50	* At the moment, we can only deal with non-wildcarded alarm times.
	51	*/
	52	ret = rtc_valid_tm(&alrm->time);
	53	if (ret == 0)
	54	ret = rtc_tm_to_time(&alrm->time, &time);
	55	if (ret == 0)
	56	writel(time, rtc->base + RTC_MR);
	57	return ret;
	58	}
	59
	60	static int pl030_read_time(struct device dev, struct rtc_time tm)
	61	{
	62	struct pl030_rtc *rtc = dev_get_drvdata(dev);
	63
	64	rtc_time_to_tm(readl(rtc->base + RTC_DR), tm);
	65
	66	return 0;
	67	}
	68
	69	/*
	70	* Set the RTC time. Unfortunately, we can't accurately set
	71	* the point at which the counter updates.
	72	*
	73	* Also, since RTC_LR is transferred to RTC_CR on next rising
	74	* edge of the 1Hz clock, we must write the time one second
	75	* in advance.
	76	*/
	77	static int pl030_set_time(struct device dev, struct rtc_time tm)
	78	{
	79	struct pl030_rtc *rtc = dev_get_drvdata(dev);
	80	unsigned long time;
	81	int ret;
	82
	83	ret = rtc_tm_to_time(tm, &time);
	84	if (ret == 0)
	85	writel(time + 1, rtc->base + RTC_LR);
	86
	87	return ret;
	88	}
	89
	90	static const struct rtc_class_ops pl030_ops = {
a190901c RK	91	.read_time = pl030_read_time,
	92	.set_time = pl030_set_time,
	93	.read_alarm = pl030_read_alarm,
	94	.set_alarm = pl030_set_alarm,
	95	};
	96
aa25afad	97	static int pl030_probe(struct amba_device dev, const struct amba_id id)
a190901c RK	98	{
	99	struct pl030_rtc *rtc;
	100	int ret;
	101
	102	ret = amba_request_regions(dev, NULL);
	103	if (ret)
	104	goto err_req;
	105
58c181c8	106	rtc = devm_kzalloc(&dev->dev, sizeof(*rtc), GFP_KERNEL);
a190901c RK	107	if (!rtc) {
	108	ret = -ENOMEM;
	109	goto err_rtc;
	110	}
	111
c778ec85 AB	112	rtc->rtc = devm_rtc_allocate_device(&dev->dev);
	113	if (IS_ERR(rtc->rtc)) {
	114	ret = PTR_ERR(rtc->rtc);
	115	goto err_rtc;
	116	}
	117
	118	rtc->rtc->ops = &pl030_ops;
dc890c2d	119	rtc->base = ioremap(dev->res.start, resource_size(&dev->res));
a190901c RK	120	if (!rtc->base) {
a190901c RK	121	ret = -ENOMEM;
58c181c8	122	goto err_rtc;
a190901c RK	123	}
	124
	125	__raw_writel(0, rtc->base + RTC_CR);
	126	__raw_writel(0, rtc->base + RTC_EOI);
	127
	128	amba_set_drvdata(dev, rtc);
	129
2f6e5f94	130	ret = request_irq(dev->irq[0], pl030_interrupt, 0,
a190901c RK	131	"rtc-pl030", rtc);
	132	if (ret)
	133	goto err_irq;
	134
c778ec85 AB	135	ret = rtc_register_device(rtc->rtc);
c778ec85 AB	136	if (ret)
a190901c	137	goto err_reg;
a190901c RK	138
	139	return 0;
	140
	141	err_reg:
	142	free_irq(dev->irq[0], rtc);
	143	err_irq:
	144	iounmap(rtc->base);
a190901c RK	145	err_rtc:
	146	amba_release_regions(dev);
	147	err_req:
	148	return ret;
	149	}
	150
	151	static int pl030_remove(struct amba_device *dev)
	152	{
	153	struct pl030_rtc *rtc = amba_get_drvdata(dev);
	154
a190901c RK	155	writel(0, rtc->base + RTC_CR);
	156
	157	free_irq(dev->irq[0], rtc);
a190901c	158	iounmap(rtc->base);
a190901c RK	159	amba_release_regions(dev);
	160
	161	return 0;
	162	}
	163
	164	static struct amba_id pl030_ids[] = {
	165	{
	166	.id = 0x00041030,
	167	.mask = 0x000fffff,
	168	},
	169	{ 0, 0 },
	170	};
	171
66bce591 DM	172	MODULE_DEVICE_TABLE(amba, pl030_ids);
66bce591 DM	173
a190901c RK	174	static struct amba_driver pl030_driver = {
	175	.drv = {
	176	.name = "rtc-pl030",
	177	},
	178	.probe = pl030_probe,
	179	.remove = pl030_remove,
	180	.id_table = pl030_ids,
	181	};
	182
9e5ed094	183	module_amba_driver(pl030_driver);
a190901c RK	184
	185	MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
	186	MODULE_DESCRIPTION("ARM AMBA PL030 RTC Driver");
	187	MODULE_LICENSE("GPL");