drivers/rtc/rtc-lp8788.c - kernel/quantenna - Git at Google

 /*
  * TI LP8788 MFD - rtc driver
  *
  * Copyright 2012 Texas Instruments
  *
  * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  *
  */

 #include <linux/err.h>
 #include <linux/irqdomain.h>
 #include <linux/mfd/lp8788.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/rtc.h>
 #include <linux/slab.h>

 /* register address */
 #define LP8788_INTEN_3			0x05
 #define LP8788_RTC_UNLOCK		0x64
 #define LP8788_RTC_SEC			0x70
 #define LP8788_ALM1_SEC			0x77
 #define LP8788_ALM1_EN			0x7D
 #define LP8788_ALM2_SEC			0x7E
 #define LP8788_ALM2_EN			0x84

 /* mask/shift bits */
 #define LP8788_INT_RTC_ALM1_M		BIT(1)	/* Addr 05h */
 #define LP8788_INT_RTC_ALM1_S		1
 #define LP8788_INT_RTC_ALM2_M		BIT(2)	/* Addr 05h */
 #define LP8788_INT_RTC_ALM2_S		2
 #define LP8788_ALM_EN_M			BIT(7)	/* Addr 7Dh or 84h */
 #define LP8788_ALM_EN_S			7

 #define DEFAULT_ALARM_SEL		LP8788_ALARM_1
 #define LP8788_MONTH_OFFSET		1
 #define LP8788_BASE_YEAR		2000
 #define MAX_WDAY_BITS			7
 #define LP8788_WDAY_SET			1
 #define RTC_UNLOCK			0x1
 #define RTC_LATCH			0x2
 #define ALARM_IRQ_FLAG			(RTC_IRQF | RTC_AF)

 enum lp8788_time {
 	LPTIME_SEC,
 	LPTIME_MIN,
 	LPTIME_HOUR,
 	LPTIME_MDAY,
 	LPTIME_MON,
 	LPTIME_YEAR,
 	LPTIME_WDAY,
 	LPTIME_MAX,
 };

 struct lp8788_rtc {
 	struct lp8788 *lp;
 	struct rtc_device *rdev;
 	enum lp8788_alarm_sel alarm;
 	int irq;
 };

 static const u8 addr_alarm_sec[LP8788_ALARM_MAX] = {
 	LP8788_ALM1_SEC,
 	LP8788_ALM2_SEC,
 };

 static const u8 addr_alarm_en[LP8788_ALARM_MAX] = {
 	LP8788_ALM1_EN,
 	LP8788_ALM2_EN,
 };

 static const u8 mask_alarm_en[LP8788_ALARM_MAX] = {
 	LP8788_INT_RTC_ALM1_M,
 	LP8788_INT_RTC_ALM2_M,
 };

 static const u8 shift_alarm_en[LP8788_ALARM_MAX] = {
 	LP8788_INT_RTC_ALM1_S,
 	LP8788_INT_RTC_ALM2_S,
 };

 static int _to_tm_wday(u8 lp8788_wday)
 {
 	int i;

 	if (lp8788_wday == 0)
 		return 0;

 	/* lookup defined weekday from read register value */
 	for (i = 0; i < MAX_WDAY_BITS; i++) {
 		if ((lp8788_wday >> i) == LP8788_WDAY_SET)
 			break;
 	}

 	return i + 1;
 }

 static inline int _to_lp8788_wday(int tm_wday)
 {
 	return LP8788_WDAY_SET << (tm_wday - 1);
 }

 static void lp8788_rtc_unlock(struct lp8788 *lp)
 {
 	lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_UNLOCK);
 	lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_LATCH);
 }

 static int lp8788_rtc_read_time(struct device *dev, struct rtc_time *tm)
 {
 	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
 	struct lp8788 *lp = rtc->lp;
 	u8 data[LPTIME_MAX];
 	int ret;

 	lp8788_rtc_unlock(lp);

 	ret = lp8788_read_multi_bytes(lp, LP8788_RTC_SEC, data,	LPTIME_MAX);
 	if (ret)
 		return ret;

 	tm->tm_sec  = data[LPTIME_SEC];
 	tm->tm_min  = data[LPTIME_MIN];
 	tm->tm_hour = data[LPTIME_HOUR];
 	tm->tm_mday = data[LPTIME_MDAY];
 	tm->tm_mon  = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
 	tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
 	tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);

 	return 0;
 }

 static int lp8788_rtc_set_time(struct device *dev, struct rtc_time *tm)
 {
 	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
 	struct lp8788 *lp = rtc->lp;
 	u8 data[LPTIME_MAX - 1];
 	int ret, i, year;

 	year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
 	if (year < 0) {
 		dev_err(lp->dev, "invalid year: %d\n", year);
 		return -EINVAL;
 	}

 	/* because rtc weekday is a readonly register, do not update */
 	data[LPTIME_SEC]  = tm->tm_sec;
 	data[LPTIME_MIN]  = tm->tm_min;
 	data[LPTIME_HOUR] = tm->tm_hour;
 	data[LPTIME_MDAY] = tm->tm_mday;
 	data[LPTIME_MON]  = tm->tm_mon + LP8788_MONTH_OFFSET;
 	data[LPTIME_YEAR] = year;

 	for (i = 0; i < ARRAY_SIZE(data); i++) {
 		ret = lp8788_write_byte(lp, LP8788_RTC_SEC + i, data[i]);
 		if (ret)
 			return ret;
 	}

 	return 0;
 }

 static int lp8788_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
 	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
 	struct lp8788 *lp = rtc->lp;
 	struct rtc_time *tm = &alarm->time;
 	u8 addr, data[LPTIME_MAX];
 	int ret;

 	addr = addr_alarm_sec[rtc->alarm];
 	ret = lp8788_read_multi_bytes(lp, addr, data, LPTIME_MAX);
 	if (ret)
 		return ret;

 	tm->tm_sec  = data[LPTIME_SEC];
 	tm->tm_min  = data[LPTIME_MIN];
 	tm->tm_hour = data[LPTIME_HOUR];
 	tm->tm_mday = data[LPTIME_MDAY];
 	tm->tm_mon  = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
 	tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
 	tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);
 	alarm->enabled = data[LPTIME_WDAY] & LP8788_ALM_EN_M;

 	return 0;
 }

 static int lp8788_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
 	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
 	struct lp8788 *lp = rtc->lp;
 	struct rtc_time *tm = &alarm->time;
 	u8 addr, data[LPTIME_MAX];
 	int ret, i, year;

 	year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
 	if (year < 0) {
 		dev_err(lp->dev, "invalid year: %d\n", year);
 		return -EINVAL;
 	}

 	data[LPTIME_SEC]  = tm->tm_sec;
 	data[LPTIME_MIN]  = tm->tm_min;
 	data[LPTIME_HOUR] = tm->tm_hour;
 	data[LPTIME_MDAY] = tm->tm_mday;
 	data[LPTIME_MON]  = tm->tm_mon + LP8788_MONTH_OFFSET;
 	data[LPTIME_YEAR] = year;
 	data[LPTIME_WDAY] = _to_lp8788_wday(tm->tm_wday);

 	for (i = 0; i < ARRAY_SIZE(data); i++) {
 		addr = addr_alarm_sec[rtc->alarm] + i;
 		ret = lp8788_write_byte(lp, addr, data[i]);
 		if (ret)
 			return ret;
 	}

 	alarm->enabled = 1;
 	addr = addr_alarm_en[rtc->alarm];

 	return lp8788_update_bits(lp, addr, LP8788_ALM_EN_M,
 				alarm->enabled << LP8788_ALM_EN_S);
 }

 static int lp8788_alarm_irq_enable(struct device *dev, unsigned int enable)
 {
 	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
 	struct lp8788 *lp = rtc->lp;
 	u8 mask, shift;

 	if (!rtc->irq)
 		return -EIO;

 	mask = mask_alarm_en[rtc->alarm];
 	shift = shift_alarm_en[rtc->alarm];

 	return lp8788_update_bits(lp, LP8788_INTEN_3, mask, enable << shift);
 }

 static const struct rtc_class_ops lp8788_rtc_ops = {
 	.read_time = lp8788_rtc_read_time,
 	.set_time = lp8788_rtc_set_time,
 	.read_alarm = lp8788_read_alarm,
 	.set_alarm = lp8788_set_alarm,
 	.alarm_irq_enable = lp8788_alarm_irq_enable,
 };

 static irqreturn_t lp8788_alarm_irq_handler(int irq, void *ptr)
 {
 	struct lp8788_rtc *rtc = ptr;

 	rtc_update_irq(rtc->rdev, 1, ALARM_IRQ_FLAG);
 	return IRQ_HANDLED;
 }

 static int lp8788_alarm_irq_register(struct platform_device *pdev,
 				struct lp8788_rtc *rtc)
 {
 	struct resource *r;
 	struct lp8788 *lp = rtc->lp;
 	struct irq_domain *irqdm = lp->irqdm;
 	int irq;

 	rtc->irq = 0;

 	/* even the alarm IRQ number is not specified, rtc time should work */
 	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, LP8788_ALM_IRQ);
 	if (!r)
 		return 0;

 	if (rtc->alarm == LP8788_ALARM_1)
 		irq = r->start;
 	else
 		irq = r->end;

 	rtc->irq = irq_create_mapping(irqdm, irq);

 	return devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
 				lp8788_alarm_irq_handler,
 				0, LP8788_ALM_IRQ, rtc);
 }

 static int lp8788_rtc_probe(struct platform_device *pdev)
 {
 	struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
 	struct lp8788_rtc *rtc;
 	struct device *dev = &pdev->dev;

 	rtc = devm_kzalloc(dev, sizeof(struct lp8788_rtc), GFP_KERNEL);
 	if (!rtc)
 		return -ENOMEM;

 	rtc->lp = lp;
 	rtc->alarm = lp->pdata ? lp->pdata->alarm_sel : DEFAULT_ALARM_SEL;
 	platform_set_drvdata(pdev, rtc);

 	device_init_wakeup(dev, 1);

 	rtc->rdev = devm_rtc_device_register(dev, "lp8788_rtc",
 					&lp8788_rtc_ops, THIS_MODULE);
 	if (IS_ERR(rtc->rdev)) {
 		dev_err(dev, "can not register rtc device\n");
 		return PTR_ERR(rtc->rdev);
 	}

 	if (lp8788_alarm_irq_register(pdev, rtc))
 		dev_warn(lp->dev, "no rtc irq handler\n");

 	return 0;
 }

 static struct platform_driver lp8788_rtc_driver = {
 	.probe = lp8788_rtc_probe,
 	.driver = {
 		.name = LP8788_DEV_RTC,
 	},
 };
 module_platform_driver(lp8788_rtc_driver);

 MODULE_DESCRIPTION("Texas Instruments LP8788 RTC Driver");
 MODULE_AUTHOR("Milo Kim");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:lp8788-rtc");
	/*
	* TI LP8788 MFD - rtc driver
	*
	* Copyright 2012 Texas Instruments
	*
	* Author: Milo(Woogyom) Kim <milo.kim@ti.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*
	*/

	#include <linux/err.h>
	#include <linux/irqdomain.h>
	#include <linux/mfd/lp8788.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/rtc.h>
	#include <linux/slab.h>

	/* register address */
	#define LP8788_INTEN_3 0x05
	#define LP8788_RTC_UNLOCK 0x64
	#define LP8788_RTC_SEC 0x70
	#define LP8788_ALM1_SEC 0x77
	#define LP8788_ALM1_EN 0x7D
	#define LP8788_ALM2_SEC 0x7E
	#define LP8788_ALM2_EN 0x84

	/* mask/shift bits */
	#define LP8788_INT_RTC_ALM1_M BIT(1) /* Addr 05h */
	#define LP8788_INT_RTC_ALM1_S 1
	#define LP8788_INT_RTC_ALM2_M BIT(2) /* Addr 05h */
	#define LP8788_INT_RTC_ALM2_S 2
	#define LP8788_ALM_EN_M BIT(7) /* Addr 7Dh or 84h */
	#define LP8788_ALM_EN_S 7

	#define DEFAULT_ALARM_SEL LP8788_ALARM_1
	#define LP8788_MONTH_OFFSET 1
	#define LP8788_BASE_YEAR 2000
	#define MAX_WDAY_BITS 7
	#define LP8788_WDAY_SET 1
	#define RTC_UNLOCK 0x1
	#define RTC_LATCH 0x2
	#define ALARM_IRQ_FLAG (RTC_IRQF \| RTC_AF)

	enum lp8788_time {
	LPTIME_SEC,
	LPTIME_MIN,
	LPTIME_HOUR,
	LPTIME_MDAY,
	LPTIME_MON,
	LPTIME_YEAR,
	LPTIME_WDAY,
	LPTIME_MAX,
	};

	struct lp8788_rtc {
	struct lp8788 *lp;
	struct rtc_device *rdev;
	enum lp8788_alarm_sel alarm;
	int irq;
	};

	static const u8 addr_alarm_sec[LP8788_ALARM_MAX] = {
	LP8788_ALM1_SEC,
	LP8788_ALM2_SEC,
	};

	static const u8 addr_alarm_en[LP8788_ALARM_MAX] = {
	LP8788_ALM1_EN,
	LP8788_ALM2_EN,
	};

	static const u8 mask_alarm_en[LP8788_ALARM_MAX] = {
	LP8788_INT_RTC_ALM1_M,
	LP8788_INT_RTC_ALM2_M,
	};

	static const u8 shift_alarm_en[LP8788_ALARM_MAX] = {
	LP8788_INT_RTC_ALM1_S,
	LP8788_INT_RTC_ALM2_S,
	};

	static int _to_tm_wday(u8 lp8788_wday)
	{
	int i;

	if (lp8788_wday == 0)
	return 0;

	/* lookup defined weekday from read register value */
	for (i = 0; i < MAX_WDAY_BITS; i++) {
	if ((lp8788_wday >> i) == LP8788_WDAY_SET)
	break;
	}

	return i + 1;
	}

	static inline int _to_lp8788_wday(int tm_wday)
	{
	return LP8788_WDAY_SET << (tm_wday - 1);
	}

	static void lp8788_rtc_unlock(struct lp8788 *lp)
	{
	lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_UNLOCK);
	lp8788_write_byte(lp, LP8788_RTC_UNLOCK, RTC_LATCH);
	}

	static int lp8788_rtc_read_time(struct device dev, struct rtc_time tm)
	{
	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
	struct lp8788 *lp = rtc->lp;
	u8 data[LPTIME_MAX];
	int ret;

	lp8788_rtc_unlock(lp);

	ret = lp8788_read_multi_bytes(lp, LP8788_RTC_SEC, data, LPTIME_MAX);
	if (ret)
	return ret;

	tm->tm_sec = data[LPTIME_SEC];
	tm->tm_min = data[LPTIME_MIN];
	tm->tm_hour = data[LPTIME_HOUR];
	tm->tm_mday = data[LPTIME_MDAY];
	tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
	tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
	tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);

	return 0;
	}

	static int lp8788_rtc_set_time(struct device dev, struct rtc_time tm)
	{
	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
	struct lp8788 *lp = rtc->lp;
	u8 data[LPTIME_MAX - 1];
	int ret, i, year;

	year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
	if (year < 0) {
	dev_err(lp->dev, "invalid year: %d\n", year);
	return -EINVAL;
	}

	/* because rtc weekday is a readonly register, do not update */
	data[LPTIME_SEC] = tm->tm_sec;
	data[LPTIME_MIN] = tm->tm_min;
	data[LPTIME_HOUR] = tm->tm_hour;
	data[LPTIME_MDAY] = tm->tm_mday;
	data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET;
	data[LPTIME_YEAR] = year;

	for (i = 0; i < ARRAY_SIZE(data); i++) {
	ret = lp8788_write_byte(lp, LP8788_RTC_SEC + i, data[i]);
	if (ret)
	return ret;
	}

	return 0;
	}

	static int lp8788_read_alarm(struct device dev, struct rtc_wkalrm alarm)
	{
	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
	struct lp8788 *lp = rtc->lp;
	struct rtc_time *tm = &alarm->time;
	u8 addr, data[LPTIME_MAX];
	int ret;

	addr = addr_alarm_sec[rtc->alarm];
	ret = lp8788_read_multi_bytes(lp, addr, data, LPTIME_MAX);
	if (ret)
	return ret;

	tm->tm_sec = data[LPTIME_SEC];
	tm->tm_min = data[LPTIME_MIN];
	tm->tm_hour = data[LPTIME_HOUR];
	tm->tm_mday = data[LPTIME_MDAY];
	tm->tm_mon = data[LPTIME_MON] - LP8788_MONTH_OFFSET;
	tm->tm_year = data[LPTIME_YEAR] + LP8788_BASE_YEAR - 1900;
	tm->tm_wday = _to_tm_wday(data[LPTIME_WDAY]);
	alarm->enabled = data[LPTIME_WDAY] & LP8788_ALM_EN_M;

	return 0;
	}

	static int lp8788_set_alarm(struct device dev, struct rtc_wkalrm alarm)
	{
	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
	struct lp8788 *lp = rtc->lp;
	struct rtc_time *tm = &alarm->time;
	u8 addr, data[LPTIME_MAX];
	int ret, i, year;

	year = tm->tm_year + 1900 - LP8788_BASE_YEAR;
	if (year < 0) {
	dev_err(lp->dev, "invalid year: %d\n", year);
	return -EINVAL;
	}

	data[LPTIME_SEC] = tm->tm_sec;
	data[LPTIME_MIN] = tm->tm_min;
	data[LPTIME_HOUR] = tm->tm_hour;
	data[LPTIME_MDAY] = tm->tm_mday;
	data[LPTIME_MON] = tm->tm_mon + LP8788_MONTH_OFFSET;
	data[LPTIME_YEAR] = year;
	data[LPTIME_WDAY] = _to_lp8788_wday(tm->tm_wday);

	for (i = 0; i < ARRAY_SIZE(data); i++) {
	addr = addr_alarm_sec[rtc->alarm] + i;
	ret = lp8788_write_byte(lp, addr, data[i]);
	if (ret)
	return ret;
	}

	alarm->enabled = 1;
	addr = addr_alarm_en[rtc->alarm];

	return lp8788_update_bits(lp, addr, LP8788_ALM_EN_M,
	alarm->enabled << LP8788_ALM_EN_S);
	}

	static int lp8788_alarm_irq_enable(struct device *dev, unsigned int enable)
	{
	struct lp8788_rtc *rtc = dev_get_drvdata(dev);
	struct lp8788 *lp = rtc->lp;
	u8 mask, shift;

	if (!rtc->irq)
	return -EIO;

	mask = mask_alarm_en[rtc->alarm];
	shift = shift_alarm_en[rtc->alarm];

	return lp8788_update_bits(lp, LP8788_INTEN_3, mask, enable << shift);
	}

	static const struct rtc_class_ops lp8788_rtc_ops = {
	.read_time = lp8788_rtc_read_time,
	.set_time = lp8788_rtc_set_time,
	.read_alarm = lp8788_read_alarm,
	.set_alarm = lp8788_set_alarm,
	.alarm_irq_enable = lp8788_alarm_irq_enable,
	};

	static irqreturn_t lp8788_alarm_irq_handler(int irq, void *ptr)
	{
	struct lp8788_rtc *rtc = ptr;

	rtc_update_irq(rtc->rdev, 1, ALARM_IRQ_FLAG);
	return IRQ_HANDLED;
	}

	static int lp8788_alarm_irq_register(struct platform_device *pdev,
	struct lp8788_rtc *rtc)
	{
	struct resource *r;
	struct lp8788 *lp = rtc->lp;
	struct irq_domain *irqdm = lp->irqdm;
	int irq;

	rtc->irq = 0;

	/* even the alarm IRQ number is not specified, rtc time should work */
	r = platform_get_resource_byname(pdev, IORESOURCE_IRQ, LP8788_ALM_IRQ);
	if (!r)
	return 0;

	if (rtc->alarm == LP8788_ALARM_1)
	irq = r->start;
	else
	irq = r->end;

	rtc->irq = irq_create_mapping(irqdm, irq);

	return devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,
	lp8788_alarm_irq_handler,
	0, LP8788_ALM_IRQ, rtc);
	}

	static int lp8788_rtc_probe(struct platform_device *pdev)
	{
	struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);
	struct lp8788_rtc *rtc;
	struct device *dev = &pdev->dev;

	rtc = devm_kzalloc(dev, sizeof(struct lp8788_rtc), GFP_KERNEL);
	if (!rtc)
	return -ENOMEM;

	rtc->lp = lp;
	rtc->alarm = lp->pdata ? lp->pdata->alarm_sel : DEFAULT_ALARM_SEL;
	platform_set_drvdata(pdev, rtc);

	device_init_wakeup(dev, 1);

	rtc->rdev = devm_rtc_device_register(dev, "lp8788_rtc",
	&lp8788_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc->rdev)) {
	dev_err(dev, "can not register rtc device\n");
	return PTR_ERR(rtc->rdev);
	}

	if (lp8788_alarm_irq_register(pdev, rtc))
	dev_warn(lp->dev, "no rtc irq handler\n");

	return 0;
	}

	static struct platform_driver lp8788_rtc_driver = {
	.probe = lp8788_rtc_probe,
	.driver = {
	.name = LP8788_DEV_RTC,
	},
	};
	module_platform_driver(lp8788_rtc_driver);

	MODULE_DESCRIPTION("Texas Instruments LP8788 RTC Driver");
	MODULE_AUTHOR("Milo Kim");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:lp8788-rtc");