[mirror_ubuntu-bionic-kernel.git] / drivers / rtc / rtc-rk808.c

/*
 * RTC driver for Rockchip RK808
 *
 * Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
 *
 * Author: Chris Zhong <zyw@rock-chips.com>
 * Author: Zhang Qing <zhangqing@rock-chips.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
#include <linux/mfd/rk808.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>

/* RTC_CTRL_REG bitfields */
#define BIT_RTC_CTRL_REG_STOP_RTC_M		BIT(0)

/* RK808 has a shadowed register for saving a "frozen" RTC time.
 * When user setting "GET_TIME" to 1, the time will save in this shadowed
 * register. If set "READSEL" to 1, user read rtc time register, actually
 * get the time of that moment. If we need the real time, clr this bit.
 */
#define BIT_RTC_CTRL_REG_RTC_GET_TIME		BIT(6)
#define BIT_RTC_CTRL_REG_RTC_READSEL_M		BIT(7)
#define BIT_RTC_INTERRUPTS_REG_IT_ALARM_M	BIT(3)
#define RTC_STATUS_MASK		0xFE

#define SECONDS_REG_MSK		0x7F
#define MINUTES_REG_MAK		0x7F
#define HOURS_REG_MSK		0x3F
#define DAYS_REG_MSK		0x3F
#define MONTHS_REG_MSK		0x1F
#define YEARS_REG_MSK		0xFF
#define WEEKS_REG_MSK		0x7

/* REG_SECONDS_REG through REG_YEARS_REG is how many registers? */

#define NUM_TIME_REGS	(RK808_WEEKS_REG - RK808_SECONDS_REG + 1)
#define NUM_ALARM_REGS	(RK808_ALARM_YEARS_REG - RK808_ALARM_SECONDS_REG + 1)

struct rk808_rtc {
	struct rk808 *rk808;
	struct rtc_device *rtc;
	int irq;
};

/* Read current time and date in RTC */
static int rk808_rtc_readtime(struct device *dev, struct rtc_time *tm)
{
	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
	struct rk808 *rk808 = rk808_rtc->rk808;
	u8 rtc_data[NUM_TIME_REGS];
	int ret;

	/* Force an update of the shadowed registers right now */
	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
				 BIT_RTC_CTRL_REG_RTC_GET_TIME,
				 0);
	if (ret) {
		dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
		return ret;
	}

	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
				 BIT_RTC_CTRL_REG_RTC_GET_TIME,
				 BIT_RTC_CTRL_REG_RTC_GET_TIME);
	if (ret) {
		dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
		return ret;
	}

	ret = regmap_bulk_read(rk808->regmap, RK808_SECONDS_REG,
			       rtc_data, NUM_TIME_REGS);
	if (ret) {
		dev_err(dev, "Failed to bulk read rtc_data: %d\n", ret);
		return ret;
	}

	tm->tm_sec = bcd2bin(rtc_data[0] & SECONDS_REG_MSK);
	tm->tm_min = bcd2bin(rtc_data[1] & MINUTES_REG_MAK);
	tm->tm_hour = bcd2bin(rtc_data[2] & HOURS_REG_MSK);
	tm->tm_mday = bcd2bin(rtc_data[3] & DAYS_REG_MSK);
	tm->tm_mon = (bcd2bin(rtc_data[4] & MONTHS_REG_MSK)) - 1;
	tm->tm_year = (bcd2bin(rtc_data[5] & YEARS_REG_MSK)) + 100;
	tm->tm_wday = bcd2bin(rtc_data[6] & WEEKS_REG_MSK);
	dev_dbg(dev, "RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
		1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
		tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);

	return ret;
}

/* Set current time and date in RTC */
static int rk808_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
	struct rk808 *rk808 = rk808_rtc->rk808;
	u8 rtc_data[NUM_TIME_REGS];
	int ret;

	rtc_data[0] = bin2bcd(tm->tm_sec);
	rtc_data[1] = bin2bcd(tm->tm_min);
	rtc_data[2] = bin2bcd(tm->tm_hour);
	rtc_data[3] = bin2bcd(tm->tm_mday);
	rtc_data[4] = bin2bcd(tm->tm_mon + 1);
	rtc_data[5] = bin2bcd(tm->tm_year - 100);
	rtc_data[6] = bin2bcd(tm->tm_wday);
	dev_dbg(dev, "set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
		1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
		tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);

	/* Stop RTC while updating the RTC registers */
	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
				 BIT_RTC_CTRL_REG_STOP_RTC_M,
				 BIT_RTC_CTRL_REG_STOP_RTC_M);
	if (ret) {
		dev_err(dev, "Failed to update RTC control: %d\n", ret);
		return ret;
	}

	ret = regmap_bulk_write(rk808->regmap, RK808_SECONDS_REG,
				rtc_data, NUM_TIME_REGS);
	if (ret) {
		dev_err(dev, "Failed to bull write rtc_data: %d\n", ret);
		return ret;
	}
	/* Start RTC again */
	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
				 BIT_RTC_CTRL_REG_STOP_RTC_M, 0);
	if (ret) {
		dev_err(dev, "Failed to update RTC control: %d\n", ret);
		return ret;
	}
	return 0;
}

/* Read alarm time and date in RTC */
static int rk808_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
	struct rk808 *rk808 = rk808_rtc->rk808;
	u8 alrm_data[NUM_ALARM_REGS];
	uint32_t int_reg;
	int ret;

	ret = regmap_bulk_read(rk808->regmap, RK808_ALARM_SECONDS_REG,
			       alrm_data, NUM_ALARM_REGS);

	alrm->time.tm_sec = bcd2bin(alrm_data[0] & SECONDS_REG_MSK);
	alrm->time.tm_min = bcd2bin(alrm_data[1] & MINUTES_REG_MAK);
	alrm->time.tm_hour = bcd2bin(alrm_data[2] & HOURS_REG_MSK);
	alrm->time.tm_mday = bcd2bin(alrm_data[3] & DAYS_REG_MSK);
	alrm->time.tm_mon = (bcd2bin(alrm_data[4] & MONTHS_REG_MSK)) - 1;
	alrm->time.tm_year = (bcd2bin(alrm_data[5] & YEARS_REG_MSK)) + 100;

	ret = regmap_read(rk808->regmap, RK808_RTC_INT_REG, &int_reg);
	if (ret) {
		dev_err(dev, "Failed to read RTC INT REG: %d\n", ret);
		return ret;
	}

	dev_dbg(dev, "alrm read RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
		1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
		alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
		alrm->time.tm_min, alrm->time.tm_sec);

	alrm->enabled = (int_reg & BIT_RTC_INTERRUPTS_REG_IT_ALARM_M) ? 1 : 0;

	return 0;
}

static int rk808_rtc_stop_alarm(struct rk808_rtc *rk808_rtc)
{
	struct rk808 *rk808 = rk808_rtc->rk808;
	int ret;

	ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
				 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M, 0);

	return ret;
}

static int rk808_rtc_start_alarm(struct rk808_rtc *rk808_rtc)
{
	struct rk808 *rk808 = rk808_rtc->rk808;
	int ret;

	ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
				 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M,
				 BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);

	return ret;
}

static int rk808_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
	struct rk808 *rk808 = rk808_rtc->rk808;
	u8 alrm_data[NUM_ALARM_REGS];
	int ret;

	ret = rk808_rtc_stop_alarm(rk808_rtc);
	if (ret) {
		dev_err(dev, "Failed to stop alarm: %d\n", ret);
		return ret;
	}
	dev_dbg(dev, "alrm set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
		1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
		alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
		alrm->time.tm_min, alrm->time.tm_sec);

	alrm_data[0] = bin2bcd(alrm->time.tm_sec);
	alrm_data[1] = bin2bcd(alrm->time.tm_min);
	alrm_data[2] = bin2bcd(alrm->time.tm_hour);
	alrm_data[3] = bin2bcd(alrm->time.tm_mday);
	alrm_data[4] = bin2bcd(alrm->time.tm_mon + 1);
	alrm_data[5] = bin2bcd(alrm->time.tm_year - 100);

	ret = regmap_bulk_write(rk808->regmap, RK808_ALARM_SECONDS_REG,
				alrm_data, NUM_ALARM_REGS);
	if (ret) {
		dev_err(dev, "Failed to bulk write: %d\n", ret);
		return ret;
	}
	if (alrm->enabled) {
		ret = rk808_rtc_start_alarm(rk808_rtc);
		if (ret) {
			dev_err(dev, "Failed to start alarm: %d\n", ret);
			return ret;
		}
	}
	return 0;
}

static int rk808_rtc_alarm_irq_enable(struct device *dev,
				      unsigned int enabled)
{
	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);

	if (enabled)
		return rk808_rtc_start_alarm(rk808_rtc);

	return rk808_rtc_stop_alarm(rk808_rtc);
}

/*
 * We will just handle setting the frequency and make use the framework for
 * reading the periodic interupts.
 *
 * @freq: Current periodic IRQ freq:
 * bit 0: every second
 * bit 1: every minute
 * bit 2: every hour
 * bit 3: every day
 */
static irqreturn_t rk808_alarm_irq(int irq, void *data)
{
	struct rk808_rtc *rk808_rtc = data;
	struct rk808 *rk808 = rk808_rtc->rk808;
	struct i2c_client *client = rk808->i2c;
	int ret;

	ret = regmap_write(rk808->regmap, RK808_RTC_STATUS_REG,
			   RTC_STATUS_MASK);
	if (ret) {
		dev_err(&client->dev,
			"%s:Failed to update RTC status: %d\n", __func__, ret);
		return ret;
	}

	rtc_update_irq(rk808_rtc->rtc, 1, RTC_IRQF | RTC_AF);
	dev_dbg(&client->dev,
		 "%s:irq=%d\n", __func__, irq);
	return IRQ_HANDLED;
}

static const struct rtc_class_ops rk808_rtc_ops = {
	.read_time = rk808_rtc_readtime,
	.set_time = rk808_rtc_set_time,
	.read_alarm = rk808_rtc_readalarm,
	.set_alarm = rk808_rtc_setalarm,
	.alarm_irq_enable = rk808_rtc_alarm_irq_enable,
};

#ifdef CONFIG_PM_SLEEP
/* Turn off the alarm if it should not be a wake source. */
static int rk808_rtc_suspend(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rk808_rtc *rk808_rtc = dev_get_drvdata(&pdev->dev);

	if (device_may_wakeup(dev))
		enable_irq_wake(rk808_rtc->irq);

	return 0;
}

/* Enable the alarm if it should be enabled (in case it was disabled to
 * prevent use as a wake source).
 */
static int rk808_rtc_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct rk808_rtc *rk808_rtc = dev_get_drvdata(&pdev->dev);

	if (device_may_wakeup(dev))
		disable_irq_wake(rk808_rtc->irq);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(rk808_rtc_pm_ops,
	rk808_rtc_suspend, rk808_rtc_resume);

static int rk808_rtc_probe(struct platform_device *pdev)
{
	struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
	struct rk808_rtc *rk808_rtc;
	struct rtc_time tm;
	int ret;

	rk808_rtc = devm_kzalloc(&pdev->dev, sizeof(*rk808_rtc), GFP_KERNEL);
	if (rk808_rtc == NULL)
		return -ENOMEM;

	platform_set_drvdata(pdev, rk808_rtc);
	rk808_rtc->rk808 = rk808;

	/* start rtc running by default, and use shadowed timer. */
	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
				 BIT_RTC_CTRL_REG_STOP_RTC_M |
				 BIT_RTC_CTRL_REG_RTC_READSEL_M,
				 BIT_RTC_CTRL_REG_RTC_READSEL_M);
	if (ret) {
		dev_err(&pdev->dev,
			"Failed to update RTC control: %d\n", ret);
		return ret;
	}

	ret = regmap_write(rk808->regmap, RK808_RTC_STATUS_REG,
			   RTC_STATUS_MASK);
	if (ret) {
		dev_err(&pdev->dev,
			"Failed to write RTC status: %d\n", ret);
			return ret;
	}

	/* set init time */
	ret = rk808_rtc_readtime(&pdev->dev, &tm);
	if (ret) {
		dev_err(&pdev->dev, "Failed to read RTC time\n");
		return ret;
	}
	ret = rtc_valid_tm(&tm);
	if (ret)
		dev_warn(&pdev->dev, "invalid date/time\n");

	device_init_wakeup(&pdev->dev, 1);

	rk808_rtc->rtc = devm_rtc_device_register(&pdev->dev, "rk808-rtc",
						  &rk808_rtc_ops, THIS_MODULE);
	if (IS_ERR(rk808_rtc->rtc)) {
		ret = PTR_ERR(rk808_rtc->rtc);
		return ret;
	}

	rk808_rtc->irq = platform_get_irq(pdev, 0);
	if (rk808_rtc->irq < 0) {
		if (rk808_rtc->irq != -EPROBE_DEFER)
			dev_err(&pdev->dev, "Wake up is not possible as irq = %d\n",
				rk808_rtc->irq);
		return rk808_rtc->irq;
	}

	/* request alarm irq of rk808 */
	ret = devm_request_threaded_irq(&pdev->dev, rk808_rtc->irq, NULL,
					rk808_alarm_irq, 0,
					"RTC alarm", rk808_rtc);
	if (ret) {
		dev_err(&pdev->dev, "Failed to request alarm IRQ %d: %d\n",
			rk808_rtc->irq, ret);
	}

	return ret;
}

static struct platform_driver rk808_rtc_driver = {
	.probe = rk808_rtc_probe,
	.driver = {
		.name = "rk808-rtc",
		.pm = &rk808_rtc_pm_ops,
	},
};

module_platform_driver(rk808_rtc_driver);

MODULE_DESCRIPTION("RTC driver for the rk808 series PMICs");
MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
MODULE_AUTHOR("Zhang Qing <zhangqing@rock-chips.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:rk808-rtc");
Commit	Line	Data
3ca1e326 CZ	1	/*
	2	* RTC driver for Rockchip RK808
	3	*
	4	* Copyright (c) 2014, Fuzhou Rockchip Electronics Co., Ltd
	5	*
	6	* Author: Chris Zhong <zyw@rock-chips.com>
	7	* Author: Zhang Qing <zhangqing@rock-chips.com>
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms and conditions of the GNU General Public License,
	11	* version 2, as published by the Free Software Foundation.
	12	*
	13	* This program is distributed in the hope it will be useful, but WITHOUT
	14	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	15	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	16	* more details.
	17	*/
	18
	19	#include <linux/module.h>
	20	#include <linux/kernel.h>
	21	#include <linux/rtc.h>
	22	#include <linux/bcd.h>
	23	#include <linux/mfd/rk808.h>
	24	#include <linux/platform_device.h>
	25	#include <linux/i2c.h>
	26
	27	/* RTC_CTRL_REG bitfields */
	28	#define BIT_RTC_CTRL_REG_STOP_RTC_M BIT(0)
	29
	30	/* RK808 has a shadowed register for saving a "frozen" RTC time.
	31	* When user setting "GET_TIME" to 1, the time will save in this shadowed
	32	* register. If set "READSEL" to 1, user read rtc time register, actually
	33	* get the time of that moment. If we need the real time, clr this bit.
	34	*/
	35	#define BIT_RTC_CTRL_REG_RTC_GET_TIME BIT(6)
	36	#define BIT_RTC_CTRL_REG_RTC_READSEL_M BIT(7)
	37	#define BIT_RTC_INTERRUPTS_REG_IT_ALARM_M BIT(3)
	38	#define RTC_STATUS_MASK 0xFE
	39
	40	#define SECONDS_REG_MSK 0x7F
	41	#define MINUTES_REG_MAK 0x7F
	42	#define HOURS_REG_MSK 0x3F
	43	#define DAYS_REG_MSK 0x3F
	44	#define MONTHS_REG_MSK 0x1F
	45	#define YEARS_REG_MSK 0xFF
	46	#define WEEKS_REG_MSK 0x7
	47
	48	/* REG_SECONDS_REG through REG_YEARS_REG is how many registers? */
	49
	50	#define NUM_TIME_REGS (RK808_WEEKS_REG - RK808_SECONDS_REG + 1)
	51	#define NUM_ALARM_REGS (RK808_ALARM_YEARS_REG - RK808_ALARM_SECONDS_REG + 1)
	52
	53	struct rk808_rtc {
	54	struct rk808 *rk808;
	55	struct rtc_device *rtc;
	56	int irq;
	57	};
	58
	59	/* Read current time and date in RTC */
	60	static int rk808_rtc_readtime(struct device dev, struct rtc_time tm)
	61	{
	62	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
	63	struct rk808 *rk808 = rk808_rtc->rk808;
	64	u8 rtc_data[NUM_TIME_REGS];
65	int ret;
66
67	/* Force an update of the shadowed registers right now */
68	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
69	BIT_RTC_CTRL_REG_RTC_GET_TIME,
70	0);
71	if (ret) {
72	dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
73	return ret;
74	}
75
76	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
77	BIT_RTC_CTRL_REG_RTC_GET_TIME,
78	BIT_RTC_CTRL_REG_RTC_GET_TIME);
79	if (ret) {
80	dev_err(dev, "Failed to update bits rtc_ctrl: %d\n", ret);
81	return ret;
82	}
83
84	ret = regmap_bulk_read(rk808->regmap, RK808_SECONDS_REG,
85	rtc_data, NUM_TIME_REGS);
86	if (ret) {
87	dev_err(dev, "Failed to bulk read rtc_data: %d\n", ret);
88	return ret;
89	}
90
91	tm->tm_sec = bcd2bin(rtc_data[0] & SECONDS_REG_MSK);
92	tm->tm_min = bcd2bin(rtc_data[1] & MINUTES_REG_MAK);
93	tm->tm_hour = bcd2bin(rtc_data[2] & HOURS_REG_MSK);
94	tm->tm_mday = bcd2bin(rtc_data[3] & DAYS_REG_MSK);
95	tm->tm_mon = (bcd2bin(rtc_data[4] & MONTHS_REG_MSK)) - 1;
96	tm->tm_year = (bcd2bin(rtc_data[5] & YEARS_REG_MSK)) + 100;
97	tm->tm_wday = bcd2bin(rtc_data[6] & WEEKS_REG_MSK);
98	dev_dbg(dev, "RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
99	1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
100	tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);
101
102	return ret;
103	}
104
105	/* Set current time and date in RTC */
106	static int rk808_rtc_set_time(struct device dev, struct rtc_time tm)
107	{
108	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
109	struct rk808 *rk808 = rk808_rtc->rk808;
110	u8 rtc_data[NUM_TIME_REGS];
111	int ret;
112
113	rtc_data[0] = bin2bcd(tm->tm_sec);
114	rtc_data[1] = bin2bcd(tm->tm_min);
115	rtc_data[2] = bin2bcd(tm->tm_hour);
116	rtc_data[3] = bin2bcd(tm->tm_mday);
117	rtc_data[4] = bin2bcd(tm->tm_mon + 1);
118	rtc_data[5] = bin2bcd(tm->tm_year - 100);
119	rtc_data[6] = bin2bcd(tm->tm_wday);
120	dev_dbg(dev, "set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
121	1900 + tm->tm_year, tm->tm_mon + 1, tm->tm_mday,
122	tm->tm_wday, tm->tm_hour , tm->tm_min, tm->tm_sec);
123
124	/* Stop RTC while updating the RTC registers */
125	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
126	BIT_RTC_CTRL_REG_STOP_RTC_M,
127	BIT_RTC_CTRL_REG_STOP_RTC_M);
128	if (ret) {
129	dev_err(dev, "Failed to update RTC control: %d\n", ret);
130	return ret;
131	}
132
133	ret = regmap_bulk_write(rk808->regmap, RK808_SECONDS_REG,
134	rtc_data, NUM_TIME_REGS);
135	if (ret) {
136	dev_err(dev, "Failed to bull write rtc_data: %d\n", ret);
137	return ret;
138	}
139	/* Start RTC again */
140	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
141	BIT_RTC_CTRL_REG_STOP_RTC_M, 0);
142	if (ret) {
143	dev_err(dev, "Failed to update RTC control: %d\n", ret);
144	return ret;
145	}
146	return 0;
147	}
148
149	/* Read alarm time and date in RTC */
150	static int rk808_rtc_readalarm(struct device dev, struct rtc_wkalrm alrm)
151	{
152	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
153	struct rk808 *rk808 = rk808_rtc->rk808;
154	u8 alrm_data[NUM_ALARM_REGS];
155	uint32_t int_reg;
156	int ret;
157
158	ret = regmap_bulk_read(rk808->regmap, RK808_ALARM_SECONDS_REG,
159	alrm_data, NUM_ALARM_REGS);
160
161	alrm->time.tm_sec = bcd2bin(alrm_data[0] & SECONDS_REG_MSK);
162	alrm->time.tm_min = bcd2bin(alrm_data[1] & MINUTES_REG_MAK);
163	alrm->time.tm_hour = bcd2bin(alrm_data[2] & HOURS_REG_MSK);
164	alrm->time.tm_mday = bcd2bin(alrm_data[3] & DAYS_REG_MSK);
165	alrm->time.tm_mon = (bcd2bin(alrm_data[4] & MONTHS_REG_MSK)) - 1;
166	alrm->time.tm_year = (bcd2bin(alrm_data[5] & YEARS_REG_MSK)) + 100;
167
168	ret = regmap_read(rk808->regmap, RK808_RTC_INT_REG, &int_reg);
169	if (ret) {
170	dev_err(dev, "Failed to read RTC INT REG: %d\n", ret);
171	return ret;
172	}
173
174	dev_dbg(dev, "alrm read RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
175	1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
176	alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
177	alrm->time.tm_min, alrm->time.tm_sec);
178
179	alrm->enabled = (int_reg & BIT_RTC_INTERRUPTS_REG_IT_ALARM_M) ? 1 : 0;
180
181	return 0;
182	}
183
184	static int rk808_rtc_stop_alarm(struct rk808_rtc *rk808_rtc)
185	{
186	struct rk808 *rk808 = rk808_rtc->rk808;
187	int ret;
188
189	ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
190	BIT_RTC_INTERRUPTS_REG_IT_ALARM_M, 0);
191
192	return ret;
193	}
194
195	static int rk808_rtc_start_alarm(struct rk808_rtc *rk808_rtc)
196	{
197	struct rk808 *rk808 = rk808_rtc->rk808;
198	int ret;
199
200	ret = regmap_update_bits(rk808->regmap, RK808_RTC_INT_REG,
201	BIT_RTC_INTERRUPTS_REG_IT_ALARM_M,
202	BIT_RTC_INTERRUPTS_REG_IT_ALARM_M);
203
204	return ret;
205	}
206
207	static int rk808_rtc_setalarm(struct device dev, struct rtc_wkalrm alrm)
208	{
209	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
210	struct rk808 *rk808 = rk808_rtc->rk808;
211	u8 alrm_data[NUM_ALARM_REGS];
212	int ret;
213
214	ret = rk808_rtc_stop_alarm(rk808_rtc);
215	if (ret) {
216	dev_err(dev, "Failed to stop alarm: %d\n", ret);
217	return ret;
218	}
219	dev_dbg(dev, "alrm set RTC date/time %4d-%02d-%02d(%d) %02d:%02d:%02d\n",
220	1900 + alrm->time.tm_year, alrm->time.tm_mon + 1,
221	alrm->time.tm_mday, alrm->time.tm_wday, alrm->time.tm_hour,
222	alrm->time.tm_min, alrm->time.tm_sec);
223
224	alrm_data[0] = bin2bcd(alrm->time.tm_sec);
225	alrm_data[1] = bin2bcd(alrm->time.tm_min);
226	alrm_data[2] = bin2bcd(alrm->time.tm_hour);
227	alrm_data[3] = bin2bcd(alrm->time.tm_mday);
228	alrm_data[4] = bin2bcd(alrm->time.tm_mon + 1);
229	alrm_data[5] = bin2bcd(alrm->time.tm_year - 100);
230
231	ret = regmap_bulk_write(rk808->regmap, RK808_ALARM_SECONDS_REG,
232	alrm_data, NUM_ALARM_REGS);
233	if (ret) {
234	dev_err(dev, "Failed to bulk write: %d\n", ret);
235	return ret;
236	}
237	if (alrm->enabled) {
238	ret = rk808_rtc_start_alarm(rk808_rtc);
239	if (ret) {
240	dev_err(dev, "Failed to start alarm: %d\n", ret);
241	return ret;
242	}
243	}
244	return 0;
245	}
246
247	static int rk808_rtc_alarm_irq_enable(struct device *dev,
248	unsigned int enabled)
249	{
250	struct rk808_rtc *rk808_rtc = dev_get_drvdata(dev);
251
252	if (enabled)
253	return rk808_rtc_start_alarm(rk808_rtc);
254
255	return rk808_rtc_stop_alarm(rk808_rtc);
256	}
257
258	/*
259	* We will just handle setting the frequency and make use the framework for
260	* reading the periodic interupts.
261	*
262	* @freq: Current periodic IRQ freq:
263	* bit 0: every second
264	* bit 1: every minute
265	* bit 2: every hour
266	* bit 3: every day
267	*/
268	static irqreturn_t rk808_alarm_irq(int irq, void *data)
269	{
270	struct rk808_rtc *rk808_rtc = data;
271	struct rk808 *rk808 = rk808_rtc->rk808;
272	struct i2c_client *client = rk808->i2c;
273	int ret;
274
275	ret = regmap_write(rk808->regmap, RK808_RTC_STATUS_REG,
276	RTC_STATUS_MASK);
277	if (ret) {
278	dev_err(&client->dev,
279	"%s:Failed to update RTC status: %d\n", __func__, ret);
280	return ret;
281	}
282
283	rtc_update_irq(rk808_rtc->rtc, 1, RTC_IRQF \| RTC_AF);
284	dev_dbg(&client->dev,
285	"%s:irq=%d\n", __func__, irq);
286	return IRQ_HANDLED;
287	}
288
289	static const struct rtc_class_ops rk808_rtc_ops = {
290	.read_time = rk808_rtc_readtime,
291	.set_time = rk808_rtc_set_time,
292	.read_alarm = rk808_rtc_readalarm,
293	.set_alarm = rk808_rtc_setalarm,
294	.alarm_irq_enable = rk808_rtc_alarm_irq_enable,
295	};
296
297	#ifdef CONFIG_PM_SLEEP
298	/* Turn off the alarm if it should not be a wake source. */
299	static int rk808_rtc_suspend(struct device *dev)
300	{
301	struct platform_device *pdev = to_platform_device(dev);
302	struct rk808_rtc *rk808_rtc = dev_get_drvdata(&pdev->dev);
303
304	if (device_may_wakeup(dev))
305	enable_irq_wake(rk808_rtc->irq);
306
307	return 0;
308	}
309
310	/* Enable the alarm if it should be enabled (in case it was disabled to
311	* prevent use as a wake source).
312	*/
313	static int rk808_rtc_resume(struct device *dev)
314	{
315	struct platform_device *pdev = to_platform_device(dev);
316	struct rk808_rtc *rk808_rtc = dev_get_drvdata(&pdev->dev);
317
318	if (device_may_wakeup(dev))
319	disable_irq_wake(rk808_rtc->irq);
320
321	return 0;
322	}
323	#endif
324
325	static SIMPLE_DEV_PM_OPS(rk808_rtc_pm_ops,
326	rk808_rtc_suspend, rk808_rtc_resume);
327
328	static int rk808_rtc_probe(struct platform_device *pdev)
329	{
330	struct rk808 *rk808 = dev_get_drvdata(pdev->dev.parent);
331	struct rk808_rtc *rk808_rtc;
332	struct rtc_time tm;
333	int ret;
334
335	rk808_rtc = devm_kzalloc(&pdev->dev, sizeof(*rk808_rtc), GFP_KERNEL);
336	if (rk808_rtc == NULL)
337	return -ENOMEM;
338
339	platform_set_drvdata(pdev, rk808_rtc);
340	rk808_rtc->rk808 = rk808;
341
342	/* start rtc running by default, and use shadowed timer. */
343	ret = regmap_update_bits(rk808->regmap, RK808_RTC_CTRL_REG,
344	BIT_RTC_CTRL_REG_STOP_RTC_M \|
345	BIT_RTC_CTRL_REG_RTC_READSEL_M,
346	BIT_RTC_CTRL_REG_RTC_READSEL_M);
347	if (ret) {
348	dev_err(&pdev->dev,
349	"Failed to update RTC control: %d\n", ret);
350	return ret;
351	}
352
353	ret = regmap_write(rk808->regmap, RK808_RTC_STATUS_REG,
354	RTC_STATUS_MASK);
355	if (ret) {
356	dev_err(&pdev->dev,
357	"Failed to write RTC status: %d\n", ret);
358	return ret;
359	}
360
361	/* set init time */
362	ret = rk808_rtc_readtime(&pdev->dev, &tm);
363	if (ret) {
364	dev_err(&pdev->dev, "Failed to read RTC time\n");
365	return ret;
366	}
367	ret = rtc_valid_tm(&tm);
368	if (ret)
369	dev_warn(&pdev->dev, "invalid date/time\n");
370
371	device_init_wakeup(&pdev->dev, 1);
372
373	rk808_rtc->rtc = devm_rtc_device_register(&pdev->dev, "rk808-rtc",
374	&rk808_rtc_ops, THIS_MODULE);
375	if (IS_ERR(rk808_rtc->rtc)) {
376	ret = PTR_ERR(rk808_rtc->rtc);
377	return ret;
378	}
379
380	rk808_rtc->irq = platform_get_irq(pdev, 0);
381	if (rk808_rtc->irq < 0) {
382	if (rk808_rtc->irq != -EPROBE_DEFER)
383	dev_err(&pdev->dev, "Wake up is not possible as irq = %d\n",
384	rk808_rtc->irq);
385	return rk808_rtc->irq;
386	}
387
388	/* request alarm irq of rk808 */
389	ret = devm_request_threaded_irq(&pdev->dev, rk808_rtc->irq, NULL,
390	rk808_alarm_irq, 0,
391	"RTC alarm", rk808_rtc);
392	if (ret) {
393	dev_err(&pdev->dev, "Failed to request alarm IRQ %d: %d\n",
394	rk808_rtc->irq, ret);
395	}
396
397	return ret;
398	}
399
400	static struct platform_driver rk808_rtc_driver = {
401	.probe = rk808_rtc_probe,
402	.driver = {
403	.name = "rk808-rtc",
404	.pm = &rk808_rtc_pm_ops,
405	},
406	};
407
408	module_platform_driver(rk808_rtc_driver);
409
410	MODULE_DESCRIPTION("RTC driver for the rk808 series PMICs");
411	MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
412	MODULE_AUTHOR("Zhang Qing <zhangqing@rock-chips.com>");
413	MODULE_LICENSE("GPL");
414	MODULE_ALIAS("platform:rk808-rtc");