// SPDX-License-Identifier: GPL-2.0-only/* * Driver for the Epson RTC module RX-8010 SJ * * Copyright(C) Timesys Corporation 2015 * Copyright(C) General Electric Company 2015 */ #include <linux/bcd.h>#include <linux/bitops.h>#include <linux/i2c.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/regmap.h>#include <linux/rtc.h> #define RX8010_SEC		0x10#define RX8010_MIN		0x11#define RX8010_HOUR		0x12#define RX8010_WDAY		0x13#define RX8010_MDAY		0x14#define RX8010_MONTH		0x15#define RX8010_YEAR		0x16#define RX8010_RESV17		0x17#define RX8010_ALMIN		0x18#define RX8010_ALHOUR		0x19#define RX8010_ALWDAY		0x1A#define RX8010_TCOUNT0		0x1B#define RX8010_TCOUNT1		0x1C#define RX8010_EXT		0x1D#define RX8010_FLAG		0x1E#define RX8010_CTRL		0x1F/* 0x20 to 0x2F are user registers */#define RX8010_RESV30		0x30#define RX8010_RESV31		0x31#define RX8010_IRQ		0x32 #define RX8010_EXT_WADA		BIT(3) #define RX8010_FLAG_VLF		BIT(1)#define RX8010_FLAG_AF		BIT(3)#define RX8010_FLAG_TF		BIT(4)#define RX8010_FLAG_UF		BIT(5) #define RX8010_CTRL_AIE		BIT(3)#define RX8010_CTRL_UIE		BIT(5)#define RX8010_CTRL_STOP	BIT(6)#define RX8010_CTRL_TEST	BIT(7) #define RX8010_ALARM_AE		BIT(7) static const struct i2c_device_id rx8010_id[] = {	{ .name = "rx8010" },	{ }};MODULE_DEVICE_TABLE(i2c, rx8010_id); static const __maybe_unused struct of_device_id rx8010_of_match[] = {	{ .compatible = "epson,rx8010" },	{ }};MODULE_DEVICE_TABLE(of, rx8010_of_match); struct rx8010_data {	struct regmap *regs;	struct rtc_device *rtc;	u8 ctrlreg;}; static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id){	struct i2c_client *client = dev_id;	struct rx8010_data *rx8010 = i2c_get_clientdata(client);	int flagreg, err; 	rtc_lock(rx8010->rtc); 	err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);	if (err) {		rtc_unlock(rx8010->rtc);		return IRQ_NONE;	} 	if (flagreg & RX8010_FLAG_VLF)		dev_warn(&client->dev, "Frequency stop detected\n"); 	if (flagreg & RX8010_FLAG_TF) {		flagreg &= ~RX8010_FLAG_TF;		rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF);	} 	if (flagreg & RX8010_FLAG_AF) {		flagreg &= ~RX8010_FLAG_AF;		rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF);	} 	if (flagreg & RX8010_FLAG_UF) {		flagreg &= ~RX8010_FLAG_UF;		rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF);	} 	err = regmap_write(rx8010->regs, RX8010_FLAG, flagreg);	rtc_unlock(rx8010->rtc);	return err ? IRQ_NONE : IRQ_HANDLED;} static int rx8010_get_time(struct device *dev, struct rtc_time *dt){	struct rx8010_data *rx8010 = dev_get_drvdata(dev);	u8 date[RX8010_YEAR - RX8010_SEC + 1];	int flagreg, err; 	err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);	if (err)		return err; 	if (flagreg & RX8010_FLAG_VLF) {		dev_warn(dev, "Frequency stop detected\n");		return -EINVAL;	} 	err = regmap_bulk_read(rx8010->regs, RX8010_SEC, date, sizeof(date));	if (err)		return err; 	dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f);	dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f);	dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f);	dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f);	dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1;	dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100;	dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f); 	return 0;} static int rx8010_set_time(struct device *dev, struct rtc_time *dt){	struct rx8010_data *rx8010 = dev_get_drvdata(dev);	u8 date[RX8010_YEAR - RX8010_SEC + 1];	int err; 	/* set STOP bit before changing clock/calendar */	err = regmap_set_bits(rx8010->regs, RX8010_CTRL, RX8010_CTRL_STOP);	if (err)		return err; 	date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec);	date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min);	date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour);	date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday);	date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1);	date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100);	date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday); 	err = regmap_bulk_write(rx8010->regs, RX8010_SEC, date, sizeof(date));	if (err)		return err; 	/* clear STOP bit after changing clock/calendar */	err = regmap_clear_bits(rx8010->regs, RX8010_CTRL, RX8010_CTRL_STOP);	if (err)		return err; 	err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_VLF);	if (err)		return err; 	return 0;} static int rx8010_init(struct device *dev){	struct rx8010_data *rx8010 = dev_get_drvdata(dev);	u8 ctrl[2];	int need_clear = 0, err; 	/* Initialize reserved registers as specified in datasheet */	err = regmap_write(rx8010->regs, RX8010_RESV17, 0xD8);	if (err)		return err; 	err = regmap_write(rx8010->regs, RX8010_RESV30, 0x00);	if (err)		return err; 	err = regmap_write(rx8010->regs, RX8010_RESV31, 0x08);	if (err)		return err; 	err = regmap_write(rx8010->regs, RX8010_IRQ, 0x00);	if (err)		return err; 	err = regmap_bulk_read(rx8010->regs, RX8010_FLAG, ctrl, 2);	if (err)		return err; 	if (ctrl[0] & RX8010_FLAG_VLF)		dev_warn(dev, "Frequency stop was detected\n"); 	if (ctrl[0] & RX8010_FLAG_AF) {		dev_warn(dev, "Alarm was detected\n");		need_clear = 1;	} 	if (ctrl[0] & RX8010_FLAG_TF)		need_clear = 1; 	if (ctrl[0] & RX8010_FLAG_UF)		need_clear = 1; 	if (need_clear) {		ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF);		err = regmap_write(rx8010->regs, RX8010_FLAG, ctrl[0]);		if (err)			return err;	} 	rx8010->ctrlreg = (ctrl[1] & ~RX8010_CTRL_TEST); 	return 0;} static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t){	struct rx8010_data *rx8010 = dev_get_drvdata(dev);	u8 alarmvals[3];	int flagreg, err; 	err = regmap_bulk_read(rx8010->regs, RX8010_ALMIN, alarmvals, 3);	if (err)		return err; 	err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);	if (err)		return err; 	t->time.tm_sec = 0;	t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f);	t->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f); 	if (!(alarmvals[2] & RX8010_ALARM_AE))		t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f); 	t->enabled = !!(rx8010->ctrlreg & RX8010_CTRL_AIE);	t->pending = (flagreg & RX8010_FLAG_AF) && t->enabled; 	return 0;} static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t){	struct rx8010_data *rx8010 = dev_get_drvdata(dev);	u8 alarmvals[3];	int err; 	if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) {		rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE);		err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg);		if (err)			return err;	} 	err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_AF);	if (err)		return err; 	alarmvals[0] = bin2bcd(t->time.tm_min);	alarmvals[1] = bin2bcd(t->time.tm_hour);	alarmvals[2] = bin2bcd(t->time.tm_mday); 	err = regmap_bulk_write(rx8010->regs, RX8010_ALMIN, alarmvals, 2);	if (err)		return err; 	err = regmap_clear_bits(rx8010->regs, RX8010_EXT, RX8010_EXT_WADA);	if (err)		return err; 	if (alarmvals[2] == 0)		alarmvals[2] |= RX8010_ALARM_AE; 	err = regmap_write(rx8010->regs, RX8010_ALWDAY, alarmvals[2]);	if (err)		return err; 	if (t->enabled) {		if (rx8010->rtc->uie_rtctimer.enabled)			rx8010->ctrlreg |= RX8010_CTRL_UIE;		if (rx8010->rtc->aie_timer.enabled)			rx8010->ctrlreg |=				(RX8010_CTRL_AIE | RX8010_CTRL_UIE); 		err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg);		if (err)			return err;	} 	return 0;} static int rx8010_alarm_irq_enable(struct device *dev,				   unsigned int enabled){	struct rx8010_data *rx8010 = dev_get_drvdata(dev);	int err;	u8 ctrl; 	ctrl = rx8010->ctrlreg; 	if (enabled) {		if (rx8010->rtc->uie_rtctimer.enabled)			ctrl |= RX8010_CTRL_UIE;		if (rx8010->rtc->aie_timer.enabled)			ctrl |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE);	} else {		if (!rx8010->rtc->uie_rtctimer.enabled)			ctrl &= ~RX8010_CTRL_UIE;		if (!rx8010->rtc->aie_timer.enabled)			ctrl &= ~RX8010_CTRL_AIE;	} 	err = regmap_clear_bits(rx8010->regs, RX8010_FLAG, RX8010_FLAG_AF);	if (err)		return err; 	if (ctrl != rx8010->ctrlreg) {		rx8010->ctrlreg = ctrl;		err = regmap_write(rx8010->regs, RX8010_CTRL, rx8010->ctrlreg);		if (err)			return err;	} 	return 0;} static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg){	struct rx8010_data *rx8010 = dev_get_drvdata(dev);	int tmp, flagreg, err; 	switch (cmd) {	case RTC_VL_READ:		err = regmap_read(rx8010->regs, RX8010_FLAG, &flagreg);		if (err)			return err; 		tmp = flagreg & RX8010_FLAG_VLF ? RTC_VL_DATA_INVALID : 0;		return put_user(tmp, (unsigned int __user *)arg); 	default:		return -ENOIOCTLCMD;	}} static const struct rtc_class_ops rx8010_rtc_ops = {	.read_time = rx8010_get_time,	.set_time = rx8010_set_time,	.ioctl = rx8010_ioctl,	.read_alarm = rx8010_read_alarm,	.set_alarm = rx8010_set_alarm,	.alarm_irq_enable = rx8010_alarm_irq_enable,}; static const struct regmap_config rx8010_regmap_config = {	.name = "rx8010-rtc",	.reg_bits = 8,	.val_bits = 8,}; static int rx8010_probe(struct i2c_client *client){	struct device *dev = &client->dev;	struct rx8010_data *rx8010;	int err = 0; 	rx8010 = devm_kzalloc(dev, sizeof(*rx8010), GFP_KERNEL);	if (!rx8010)		return -ENOMEM; 	i2c_set_clientdata(client, rx8010); 	rx8010->regs = devm_regmap_init_i2c(client, &rx8010_regmap_config);	if (IS_ERR(rx8010->regs))		return PTR_ERR(rx8010->regs); 	err = rx8010_init(dev);	if (err)		return err; 	rx8010->rtc = devm_rtc_allocate_device(dev);	if (IS_ERR(rx8010->rtc))		return PTR_ERR(rx8010->rtc); 	if (client->irq > 0) {		unsigned long irqflags = IRQF_TRIGGER_LOW; 		if (dev_fwnode(&client->dev))			irqflags = 0; 		err = devm_request_threaded_irq(dev, client->irq, NULL,						rx8010_irq_1_handler,						irqflags | IRQF_ONESHOT,						"rx8010", client);		if (err) {			dev_err(dev, "unable to request IRQ\n");			return err;		}	} else {		clear_bit(RTC_FEATURE_ALARM, rx8010->rtc->features);	} 	rx8010->rtc->ops = &rx8010_rtc_ops;	rx8010->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;	rx8010->rtc->range_max = RTC_TIMESTAMP_END_2099; 	return devm_rtc_register_device(rx8010->rtc);} static struct i2c_driver rx8010_driver = {	.driver = {		.name = "rtc-rx8010",		.of_match_table = of_match_ptr(rx8010_of_match),	},	.probe		= rx8010_probe,	.id_table	= rx8010_id,}; module_i2c_driver(rx8010_driver); MODULE_AUTHOR("Akshay Bhat <akshay.bhat@timesys.com>");MODULE_DESCRIPTION("Epson RX8010SJ RTC driver");MODULE_LICENSE("GPL v2");