[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_time64_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);

	writel(rtc_tm_to_time64(&alrm->time), rtc->base + RTC_MR);

	return 0;
}

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

	rtc_time64_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);

	writel(rtc_tm_to_time64(tm) + 1, rtc->base + RTC_LR);

	return 0;
}

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->rtc->range_max = U32_MAX;
	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 = devm_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 void 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);
}

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
c33c4713	39	rtc_time64_to_tm(readl(rtc->base + RTC_MR), &alrm->time);
a190901c RK	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);
a190901c	46
c33c4713 AB	47	writel(rtc_tm_to_time64(&alrm->time), rtc->base + RTC_MR);
	48
	49	return 0;
a190901c RK	50	}
	51
	52	static int pl030_read_time(struct device dev, struct rtc_time tm)
	53	{
	54	struct pl030_rtc *rtc = dev_get_drvdata(dev);
	55
c33c4713	56	rtc_time64_to_tm(readl(rtc->base + RTC_DR), tm);
a190901c RK	57
	58	return 0;
	59	}
	60
	61	/*
	62	* Set the RTC time. Unfortunately, we can't accurately set
	63	* the point at which the counter updates.
	64	*
	65	* Also, since RTC_LR is transferred to RTC_CR on next rising
	66	* edge of the 1Hz clock, we must write the time one second
	67	* in advance.
	68	*/
	69	static int pl030_set_time(struct device dev, struct rtc_time tm)
	70	{
	71	struct pl030_rtc *rtc = dev_get_drvdata(dev);
a190901c	72
c33c4713	73	writel(rtc_tm_to_time64(tm) + 1, rtc->base + RTC_LR);
a190901c	74
c33c4713	75	return 0;
a190901c RK	76	}
	77
	78	static const struct rtc_class_ops pl030_ops = {
a190901c RK	79	.read_time = pl030_read_time,
	80	.set_time = pl030_set_time,
	81	.read_alarm = pl030_read_alarm,
	82	.set_alarm = pl030_set_alarm,
	83	};
	84
aa25afad	85	static int pl030_probe(struct amba_device dev, const struct amba_id id)
a190901c RK	86	{
	87	struct pl030_rtc *rtc;
	88	int ret;
	89
	90	ret = amba_request_regions(dev, NULL);
	91	if (ret)
	92	goto err_req;
	93
58c181c8	94	rtc = devm_kzalloc(&dev->dev, sizeof(*rtc), GFP_KERNEL);
a190901c RK	95	if (!rtc) {
	96	ret = -ENOMEM;
	97	goto err_rtc;
	98	}
	99
c778ec85 AB	100	rtc->rtc = devm_rtc_allocate_device(&dev->dev);
	101	if (IS_ERR(rtc->rtc)) {
	102	ret = PTR_ERR(rtc->rtc);
	103	goto err_rtc;
	104	}
	105
	106	rtc->rtc->ops = &pl030_ops;
9896169a	107	rtc->rtc->range_max = U32_MAX;
dc890c2d	108	rtc->base = ioremap(dev->res.start, resource_size(&dev->res));
a190901c RK	109	if (!rtc->base) {
a190901c RK	110	ret = -ENOMEM;
58c181c8	111	goto err_rtc;
a190901c RK	112	}
	113
	114	__raw_writel(0, rtc->base + RTC_CR);
	115	__raw_writel(0, rtc->base + RTC_EOI);
	116
	117	amba_set_drvdata(dev, rtc);
	118
2f6e5f94	119	ret = request_irq(dev->irq[0], pl030_interrupt, 0,
a190901c RK	120	"rtc-pl030", rtc);
	121	if (ret)
	122	goto err_irq;
	123
fdcfd854	124	ret = devm_rtc_register_device(rtc->rtc);
c778ec85	125	if (ret)
a190901c	126	goto err_reg;
a190901c RK	127
	128	return 0;
	129
	130	err_reg:
	131	free_irq(dev->irq[0], rtc);
	132	err_irq:
	133	iounmap(rtc->base);
a190901c RK	134	err_rtc:
	135	amba_release_regions(dev);
	136	err_req:
	137	return ret;
	138	}
	139
3fd269e7	140	static void pl030_remove(struct amba_device *dev)
a190901c RK	141	{
	142	struct pl030_rtc *rtc = amba_get_drvdata(dev);
	143
a190901c RK	144	writel(0, rtc->base + RTC_CR);
	145
	146	free_irq(dev->irq[0], rtc);
a190901c	147	iounmap(rtc->base);
a190901c	148	amba_release_regions(dev);
a190901c RK	149	}
	150
	151	static struct amba_id pl030_ids[] = {
	152	{
	153	.id = 0x00041030,
	154	.mask = 0x000fffff,
	155	},
	156	{ 0, 0 },
	157	};
	158
66bce591 DM	159	MODULE_DEVICE_TABLE(amba, pl030_ids);
66bce591 DM	160
a190901c RK	161	static struct amba_driver pl030_driver = {
	162	.drv = {
	163	.name = "rtc-pl030",
	164	},
	165	.probe = pl030_probe,
	166	.remove = pl030_remove,
	167	.id_table = pl030_ids,
	168	};
	169
9e5ed094	170	module_amba_driver(pl030_driver);
a190901c RK	171
	172	MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
	173	MODULE_DESCRIPTION("ARM AMBA PL030 RTC Driver");
	174	MODULE_LICENSE("GPL");