[mirror_ubuntu-bionic-kernel.git] / drivers / rtc / rtc-ftrtc010.c

/*
 *  Faraday Technology FTRTC010 driver
 *
 *  Copyright (C) 2009 Janos Laube <janos.dev@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Original code for older kernel 2.6.15 are from Stormlinksemi
 * first update from Janos Laube for > 2.6.29 kernels
 *
 * checkpatch fixes and usage of rtc-lib code
 * Hans Ulli Kroll <ulli.kroll@googlemail.com>
 */

#include <linux/rtc.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/clk.h>

#define DRV_NAME        "rtc-ftrtc010"

MODULE_AUTHOR("Hans Ulli Kroll <ulli.kroll@googlemail.com>");
MODULE_DESCRIPTION("RTC driver for Gemini SoC");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:" DRV_NAME);

struct ftrtc010_rtc {
	struct rtc_device	*rtc_dev;
	void __iomem		*rtc_base;
	int			rtc_irq;
	struct clk		*pclk;
	struct clk		*extclk;
};

enum ftrtc010_rtc_offsets {
	FTRTC010_RTC_SECOND		= 0x00,
	FTRTC010_RTC_MINUTE		= 0x04,
	FTRTC010_RTC_HOUR		= 0x08,
	FTRTC010_RTC_DAYS		= 0x0C,
	FTRTC010_RTC_ALARM_SECOND	= 0x10,
	FTRTC010_RTC_ALARM_MINUTE	= 0x14,
	FTRTC010_RTC_ALARM_HOUR		= 0x18,
	FTRTC010_RTC_RECORD		= 0x1C,
	FTRTC010_RTC_CR			= 0x20,
};

static irqreturn_t ftrtc010_rtc_interrupt(int irq, void *dev)
{
	return IRQ_HANDLED;
}

/*
 * Looks like the RTC in the Gemini SoC is (totaly) broken
 * We can't read/write directly the time from RTC registers.
 * We must do some "offset" calculation to get the real time
 *
 * This FIX works pretty fine and Stormlinksemi aka Cortina-Networks does
 * the same thing, without the rtc-lib.c calls.
 */

static int ftrtc010_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);

	unsigned int  days, hour, min, sec;
	unsigned long offset, time;

	sec  = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
	min  = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
	hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
	days = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);
	offset = readl(rtc->rtc_base + FTRTC010_RTC_RECORD);

	time = offset + days * 86400 + hour * 3600 + min * 60 + sec;

	rtc_time_to_tm(time, tm);

	return 0;
}

static int ftrtc010_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);
	unsigned int sec, min, hour, day;
	unsigned long offset, time;

	if (tm->tm_year >= 2148)	/* EPOCH Year + 179 */
		return -EINVAL;

	rtc_tm_to_time(tm, &time);

	sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
	min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
	hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
	day = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);

	offset = time - (day * 86400 + hour * 3600 + min * 60 + sec);

	writel(offset, rtc->rtc_base + FTRTC010_RTC_RECORD);
	writel(0x01, rtc->rtc_base + FTRTC010_RTC_CR);

	return 0;
}

static const struct rtc_class_ops ftrtc010_rtc_ops = {
	.read_time     = ftrtc010_rtc_read_time,
	.set_time      = ftrtc010_rtc_set_time,
};

static int ftrtc010_rtc_probe(struct platform_device *pdev)
{
	struct ftrtc010_rtc *rtc;
	struct device *dev = &pdev->dev;
	struct resource *res;
	int ret;

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

	rtc->pclk = devm_clk_get(dev, "PCLK");
	if (IS_ERR(rtc->pclk)) {
		dev_err(dev, "could not get PCLK\n");
	} else {
		ret = clk_prepare_enable(rtc->pclk);
		if (ret) {
			dev_err(dev, "failed to enable PCLK\n");
			return ret;
		}
	}
	rtc->extclk = devm_clk_get(dev, "EXTCLK");
	if (IS_ERR(rtc->extclk)) {
		dev_err(dev, "could not get EXTCLK\n");
	} else {
		ret = clk_prepare_enable(rtc->extclk);
		if (ret) {
			dev_err(dev, "failed to enable EXTCLK\n");
			return ret;
		}
	}

	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	if (!res)
		return -ENODEV;

	rtc->rtc_irq = res->start;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -ENODEV;

	rtc->rtc_base = devm_ioremap(dev, res->start,
				     resource_size(res));
	if (!rtc->rtc_base)
		return -ENOMEM;

	ret = devm_request_irq(dev, rtc->rtc_irq, ftrtc010_rtc_interrupt,
			       IRQF_SHARED, pdev->name, dev);
	if (unlikely(ret))
		return ret;

	rtc->rtc_dev = rtc_device_register(pdev->name, dev,
					   &ftrtc010_rtc_ops, THIS_MODULE);
	return PTR_ERR_OR_ZERO(rtc->rtc_dev);
}

static int ftrtc010_rtc_remove(struct platform_device *pdev)
{
	struct ftrtc010_rtc *rtc = platform_get_drvdata(pdev);

	if (!IS_ERR(rtc->extclk))
		clk_disable_unprepare(rtc->extclk);
	if (!IS_ERR(rtc->pclk))
		clk_disable_unprepare(rtc->pclk);
	rtc_device_unregister(rtc->rtc_dev);

	return 0;
}

static const struct of_device_id ftrtc010_rtc_dt_match[] = {
	{ .compatible = "cortina,gemini-rtc" },
	{ .compatible = "faraday,ftrtc010" },
	{ }
};
MODULE_DEVICE_TABLE(of, ftrtc010_rtc_dt_match);

static struct platform_driver ftrtc010_rtc_driver = {
	.driver		= {
		.name	= DRV_NAME,
		.of_match_table = ftrtc010_rtc_dt_match,
	},
	.probe		= ftrtc010_rtc_probe,
	.remove		= ftrtc010_rtc_remove,
};

module_platform_driver_probe(ftrtc010_rtc_driver, ftrtc010_rtc_probe);
Commit	Line	Data
98a9bb5b	1	/*
1d61d259	2	* Faraday Technology FTRTC010 driver
98a9bb5b HUK	3	*
	4	* Copyright (C) 2009 Janos Laube <janos.dev@gmail.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* Original code for older kernel 2.6.15 are from Stormlinksemi
	17	* first update from Janos Laube for > 2.6.29 kernels
	18	*
	19	* checkpatch fixes and usage of rtc-lib code
	20	* Hans Ulli Kroll <ulli.kroll@googlemail.com>
	21	*/
	22
	23	#include <linux/rtc.h>
	24	#include <linux/io.h>
	25	#include <linux/slab.h>
	26	#include <linux/platform_device.h>
	27	#include <linux/kernel.h>
	28	#include <linux/module.h>
ac05fba3	29	#include <linux/clk.h>
98a9bb5b	30
1d61d259	31	#define DRV_NAME "rtc-ftrtc010"
98a9bb5b HUK	32
	33	MODULE_AUTHOR("Hans Ulli Kroll <ulli.kroll@googlemail.com>");
	34	MODULE_DESCRIPTION("RTC driver for Gemini SoC");
	35	MODULE_LICENSE("GPL");
	36	MODULE_ALIAS("platform:" DRV_NAME);
	37
1d61d259	38	struct ftrtc010_rtc {
98a9bb5b HUK	39	struct rtc_device *rtc_dev;
	40	void __iomem *rtc_base;
	41	int rtc_irq;
ac05fba3 LW	42	struct clk *pclk;
ac05fba3 LW	43	struct clk *extclk;
98a9bb5b HUK	44	};
98a9bb5b HUK	45
1d61d259 LW	46	enum ftrtc010_rtc_offsets {
	47	FTRTC010_RTC_SECOND = 0x00,
	48	FTRTC010_RTC_MINUTE = 0x04,
	49	FTRTC010_RTC_HOUR = 0x08,
	50	FTRTC010_RTC_DAYS = 0x0C,
	51	FTRTC010_RTC_ALARM_SECOND = 0x10,
	52	FTRTC010_RTC_ALARM_MINUTE = 0x14,
	53	FTRTC010_RTC_ALARM_HOUR = 0x18,
	54	FTRTC010_RTC_RECORD = 0x1C,
	55	FTRTC010_RTC_CR = 0x20,
98a9bb5b HUK	56	};
98a9bb5b HUK	57
1d61d259	58	static irqreturn_t ftrtc010_rtc_interrupt(int irq, void *dev)
98a9bb5b HUK	59	{
	60	return IRQ_HANDLED;
	61	}
	62
	63	/*
	64	* Looks like the RTC in the Gemini SoC is (totaly) broken
	65	* We can't read/write directly the time from RTC registers.
	66	* We must do some "offset" calculation to get the real time
	67	*
	68	* This FIX works pretty fine and Stormlinksemi aka Cortina-Networks does
	69	* the same thing, without the rtc-lib.c calls.
	70	*/
	71
1d61d259	72	static int ftrtc010_rtc_read_time(struct device dev, struct rtc_time tm)
98a9bb5b	73	{
1d61d259	74	struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);
98a9bb5b HUK	75
	76	unsigned int days, hour, min, sec;
	77	unsigned long offset, time;
	78
1d61d259 LW	79	sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
	80	min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
	81	hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
	82	days = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);
	83	offset = readl(rtc->rtc_base + FTRTC010_RTC_RECORD);
98a9bb5b HUK	84
	85	time = offset + days * 86400 + hour * 3600 + min * 60 + sec;
	86
	87	rtc_time_to_tm(time, tm);
	88
	89	return 0;
	90	}
	91
1d61d259	92	static int ftrtc010_rtc_set_time(struct device dev, struct rtc_time tm)
98a9bb5b	93	{
1d61d259	94	struct ftrtc010_rtc *rtc = dev_get_drvdata(dev);
98a9bb5b HUK	95	unsigned int sec, min, hour, day;
	96	unsigned long offset, time;
	97
	98	if (tm->tm_year >= 2148) /* EPOCH Year + 179 */
	99	return -EINVAL;
	100
	101	rtc_tm_to_time(tm, &time);
	102
1d61d259 LW	103	sec = readl(rtc->rtc_base + FTRTC010_RTC_SECOND);
	104	min = readl(rtc->rtc_base + FTRTC010_RTC_MINUTE);
	105	hour = readl(rtc->rtc_base + FTRTC010_RTC_HOUR);
	106	day = readl(rtc->rtc_base + FTRTC010_RTC_DAYS);
98a9bb5b HUK	107
	108	offset = time - (day * 86400 + hour * 3600 + min * 60 + sec);
	109
1d61d259 LW	110	writel(offset, rtc->rtc_base + FTRTC010_RTC_RECORD);
1d61d259 LW	111	writel(0x01, rtc->rtc_base + FTRTC010_RTC_CR);
98a9bb5b HUK	112
	113	return 0;
	114	}
	115
1d61d259 LW	116	static const struct rtc_class_ops ftrtc010_rtc_ops = {
	117	.read_time = ftrtc010_rtc_read_time,
	118	.set_time = ftrtc010_rtc_set_time,
98a9bb5b HUK	119	};
98a9bb5b HUK	120
1d61d259	121	static int ftrtc010_rtc_probe(struct platform_device *pdev)
98a9bb5b	122	{
1d61d259	123	struct ftrtc010_rtc *rtc;
98a9bb5b HUK	124	struct device *dev = &pdev->dev;
	125	struct resource *res;
	126	int ret;
	127
	128	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
	129	if (unlikely(!rtc))
	130	return -ENOMEM;
	131	platform_set_drvdata(pdev, rtc);
	132
ac05fba3 LW	133	rtc->pclk = devm_clk_get(dev, "PCLK");
	134	if (IS_ERR(rtc->pclk)) {
	135	dev_err(dev, "could not get PCLK\n");
	136	} else {
	137	ret = clk_prepare_enable(rtc->pclk);
	138	if (ret) {
	139	dev_err(dev, "failed to enable PCLK\n");
	140	return ret;
	141	}
	142	}
	143	rtc->extclk = devm_clk_get(dev, "EXTCLK");
	144	if (IS_ERR(rtc->extclk)) {
	145	dev_err(dev, "could not get EXTCLK\n");
	146	} else {
	147	ret = clk_prepare_enable(rtc->extclk);
	148	if (ret) {
	149	dev_err(dev, "failed to enable EXTCLK\n");
	150	return ret;
	151	}
	152	}
	153
98a9bb5b HUK	154	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
	155	if (!res)
	156	return -ENODEV;
	157
	158	rtc->rtc_irq = res->start;
	159
	160	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	161	if (!res)
	162	return -ENODEV;
	163
	164	rtc->rtc_base = devm_ioremap(dev, res->start,
45b4c85b	165	resource_size(res));
332e0d13 PB	166	if (!rtc->rtc_base)
332e0d13 PB	167	return -ENOMEM;
98a9bb5b	168
1d61d259	169	ret = devm_request_irq(dev, rtc->rtc_irq, ftrtc010_rtc_interrupt,
98a9bb5b HUK	170	IRQF_SHARED, pdev->name, dev);
	171	if (unlikely(ret))
	172	return ret;
	173
	174	rtc->rtc_dev = rtc_device_register(pdev->name, dev,
1d61d259	175	&ftrtc010_rtc_ops, THIS_MODULE);
202cc98a	176	return PTR_ERR_OR_ZERO(rtc->rtc_dev);
98a9bb5b HUK	177	}
98a9bb5b HUK	178
1d61d259	179	static int ftrtc010_rtc_remove(struct platform_device *pdev)
98a9bb5b	180	{
1d61d259	181	struct ftrtc010_rtc *rtc = platform_get_drvdata(pdev);
98a9bb5b	182
ac05fba3 LW	183	if (!IS_ERR(rtc->extclk))
	184	clk_disable_unprepare(rtc->extclk);
	185	if (!IS_ERR(rtc->pclk))
	186	clk_disable_unprepare(rtc->pclk);
98a9bb5b	187	rtc_device_unregister(rtc->rtc_dev);
98a9bb5b HUK	188
	189	return 0;
	190	}
	191
1d61d259	192	static const struct of_device_id ftrtc010_rtc_dt_match[] = {
bc7d8ebf	193	{ .compatible = "cortina,gemini-rtc" },
1d61d259	194	{ .compatible = "faraday,ftrtc010" },
bc7d8ebf LW	195	{ }
bc7d8ebf LW	196	};
1d61d259	197	MODULE_DEVICE_TABLE(of, ftrtc010_rtc_dt_match);
bc7d8ebf	198
1d61d259	199	static struct platform_driver ftrtc010_rtc_driver = {
98a9bb5b HUK	200	.driver = {
98a9bb5b HUK	201	.name = DRV_NAME,
1d61d259	202	.of_match_table = ftrtc010_rtc_dt_match,
98a9bb5b	203	},
1d61d259 LW	204	.probe = ftrtc010_rtc_probe,
1d61d259 LW	205	.remove = ftrtc010_rtc_remove,
98a9bb5b HUK	206	};
98a9bb5b HUK	207
1d61d259	208	module_platform_driver_probe(ftrtc010_rtc_driver, ftrtc010_rtc_probe);