// SPDX-License-Identifier: GPL-2.0-only/* * Real-time clock driver for MPC5121 * * Copyright 2007, Domen Puncer <domen.puncer@telargo.com> * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved. * Copyright 2011, Dmitry Eremin-Solenikov */ #include <linux/init.h>#include <linux/module.h>#include <linux/rtc.h>#include <linux/of.h>#include <linux/of_irq.h>#include <linux/platform_device.h>#include <linux/io.h>#include <linux/slab.h> struct mpc5121_rtc_regs {	u8 set_time;		/* RTC + 0x00 */	u8 hour_set;		/* RTC + 0x01 */	u8 minute_set;		/* RTC + 0x02 */	u8 second_set;		/* RTC + 0x03 */ 	u8 set_date;		/* RTC + 0x04 */	u8 month_set;		/* RTC + 0x05 */	u8 weekday_set;		/* RTC + 0x06 */	u8 date_set;		/* RTC + 0x07 */ 	u8 write_sw;		/* RTC + 0x08 */	u8 sw_set;		/* RTC + 0x09 */	u16 year_set;		/* RTC + 0x0a */ 	u8 alm_enable;		/* RTC + 0x0c */	u8 alm_hour_set;	/* RTC + 0x0d */	u8 alm_min_set;		/* RTC + 0x0e */	u8 int_enable;		/* RTC + 0x0f */ 	u8 reserved1;	u8 hour;		/* RTC + 0x11 */	u8 minute;		/* RTC + 0x12 */	u8 second;		/* RTC + 0x13 */ 	u8 month;		/* RTC + 0x14 */	u8 wday_mday;		/* RTC + 0x15 */	u16 year;		/* RTC + 0x16 */ 	u8 int_alm;		/* RTC + 0x18 */	u8 int_sw;		/* RTC + 0x19 */	u8 alm_status;		/* RTC + 0x1a */	u8 sw_minute;		/* RTC + 0x1b */ 	u8 bus_error_1;		/* RTC + 0x1c */	u8 int_day;		/* RTC + 0x1d */	u8 int_min;		/* RTC + 0x1e */	u8 int_sec;		/* RTC + 0x1f */ 	/*	 * target_time:	 *	intended to be used for hibernation but hibernation	 *	does not work on silicon rev 1.5 so use it for non-volatile	 *	storage of offset between the actual_time register and linux	 *	time	 */	u32 target_time;	/* RTC + 0x20 */	/*	 * actual_time:	 *	readonly time since VBAT_RTC was last connected	 */	u32 actual_time;	/* RTC + 0x24 */	u32 keep_alive;		/* RTC + 0x28 */}; struct mpc5121_rtc_data {	unsigned irq;	unsigned irq_periodic;	struct mpc5121_rtc_regs __iomem *regs;	struct rtc_device *rtc;	struct rtc_wkalrm wkalarm;}; /* * Update second/minute/hour registers. * * This is just so alarm will work. */static void mpc5121_rtc_update_smh(struct mpc5121_rtc_regs __iomem *regs,				   struct rtc_time *tm){	out_8(&regs->second_set, tm->tm_sec);	out_8(&regs->minute_set, tm->tm_min);	out_8(&regs->hour_set, tm->tm_hour); 	/* set time sequence */	out_8(&regs->set_time, 0x1);	out_8(&regs->set_time, 0x3);	out_8(&regs->set_time, 0x1);	out_8(&regs->set_time, 0x0);} static int mpc5121_rtc_read_time(struct device *dev, struct rtc_time *tm){	struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs;	unsigned long now; 	/*	 * linux time is actual_time plus the offset saved in target_time	 */	now = in_be32(&regs->actual_time) + in_be32(&regs->target_time); 	rtc_time64_to_tm(now, tm); 	/*	 * update second minute hour registers	 * so alarms will work	 */	mpc5121_rtc_update_smh(regs, tm); 	return 0;} static int mpc5121_rtc_set_time(struct device *dev, struct rtc_time *tm){	struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs;	unsigned long now; 	/*	 * The actual_time register is read only so we write the offset	 * between it and linux time to the target_time register.	 */	now = rtc_tm_to_time64(tm);	out_be32(&regs->target_time, now - in_be32(&regs->actual_time)); 	/*	 * update second minute hour registers	 * so alarms will work	 */	mpc5121_rtc_update_smh(regs, tm); 	return 0;} static int mpc5200_rtc_read_time(struct device *dev, struct rtc_time *tm){	struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs;	int tmp; 	tm->tm_sec = in_8(&regs->second);	tm->tm_min = in_8(&regs->minute); 	/* 12 hour format? */	if (in_8(&regs->hour) & 0x20)		tm->tm_hour = (in_8(&regs->hour) >> 1) +			(in_8(&regs->hour) & 1 ? 12 : 0);	else		tm->tm_hour = in_8(&regs->hour); 	tmp = in_8(&regs->wday_mday);	tm->tm_mday = tmp & 0x1f;	tm->tm_mon = in_8(&regs->month) - 1;	tm->tm_year = in_be16(&regs->year) - 1900;	tm->tm_wday = (tmp >> 5) % 7;	tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);	tm->tm_isdst = 0; 	return 0;} static int mpc5200_rtc_set_time(struct device *dev, struct rtc_time *tm){	struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 	mpc5121_rtc_update_smh(regs, tm); 	/* date */	out_8(&regs->month_set, tm->tm_mon + 1);	out_8(&regs->weekday_set, tm->tm_wday ? tm->tm_wday : 7);	out_8(&regs->date_set, tm->tm_mday);	out_be16(&regs->year_set, tm->tm_year + 1900); 	/* set date sequence */	out_8(&regs->set_date, 0x1);	out_8(&regs->set_date, 0x3);	out_8(&regs->set_date, 0x1);	out_8(&regs->set_date, 0x0); 	return 0;} static int mpc5121_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm){	struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 	*alarm = rtc->wkalarm; 	alarm->pending = in_8(&regs->alm_status); 	return 0;} static int mpc5121_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm){	struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 	alarm->time.tm_mday = -1;	alarm->time.tm_mon = -1;	alarm->time.tm_year = -1; 	out_8(&regs->alm_min_set, alarm->time.tm_min);	out_8(&regs->alm_hour_set, alarm->time.tm_hour); 	out_8(&regs->alm_enable, alarm->enabled); 	rtc->wkalarm = *alarm;	return 0;} static irqreturn_t mpc5121_rtc_handler(int irq, void *dev){	struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 	if (in_8(&regs->int_alm)) {		/* acknowledge and clear status */		out_8(&regs->int_alm, 1);		out_8(&regs->alm_status, 1); 		rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);		return IRQ_HANDLED;	} 	return IRQ_NONE;} static irqreturn_t mpc5121_rtc_handler_upd(int irq, void *dev){	struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 	if (in_8(&regs->int_sec) && (in_8(&regs->int_enable) & 0x1)) {		/* acknowledge */		out_8(&regs->int_sec, 1); 		rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF);		return IRQ_HANDLED;	} 	return IRQ_NONE;} static int mpc5121_rtc_alarm_irq_enable(struct device *dev,					unsigned int enabled){	struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs;	int val; 	if (enabled)		val = 1;	else		val = 0; 	out_8(&regs->alm_enable, val);	rtc->wkalarm.enabled = val; 	return 0;} static const struct rtc_class_ops mpc5121_rtc_ops = {	.read_time = mpc5121_rtc_read_time,	.set_time = mpc5121_rtc_set_time,	.read_alarm = mpc5121_rtc_read_alarm,	.set_alarm = mpc5121_rtc_set_alarm,	.alarm_irq_enable = mpc5121_rtc_alarm_irq_enable,}; static const struct rtc_class_ops mpc5200_rtc_ops = {	.read_time = mpc5200_rtc_read_time,	.set_time = mpc5200_rtc_set_time,	.read_alarm = mpc5121_rtc_read_alarm,	.set_alarm = mpc5121_rtc_set_alarm,	.alarm_irq_enable = mpc5121_rtc_alarm_irq_enable,}; static int mpc5121_rtc_probe(struct platform_device *op){	struct mpc5121_rtc_data *rtc;	int err = 0; 	rtc = devm_kzalloc(&op->dev, sizeof(*rtc), GFP_KERNEL);	if (!rtc)		return -ENOMEM; 	rtc->regs = devm_platform_ioremap_resource(op, 0);	if (IS_ERR(rtc->regs)) {		dev_err(&op->dev, "%s: couldn't map io space\n", __func__);		return PTR_ERR(rtc->regs);	} 	device_init_wakeup(&op->dev, true); 	platform_set_drvdata(op, rtc); 	rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1);	err = devm_request_irq(&op->dev, rtc->irq, mpc5121_rtc_handler, 0,			       "mpc5121-rtc", &op->dev);	if (err) {		dev_err(&op->dev, "%s: could not request irq: %i\n",							__func__, rtc->irq);		goto out_dispose;	} 	rtc->irq_periodic = irq_of_parse_and_map(op->dev.of_node, 0);	err = devm_request_irq(&op->dev, rtc->irq_periodic,			       mpc5121_rtc_handler_upd, 0, "mpc5121-rtc_upd",			       &op->dev);	if (err) {		dev_err(&op->dev, "%s: could not request irq: %i\n",						__func__, rtc->irq_periodic);		goto out_dispose2;	} 	rtc->rtc = devm_rtc_allocate_device(&op->dev);	if (IS_ERR(rtc->rtc)) {		err = PTR_ERR(rtc->rtc);		goto out_dispose2;	} 	rtc->rtc->ops = &mpc5200_rtc_ops;	set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtc->features);	clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtc->features);	rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000;	rtc->rtc->range_max = 65733206399ULL; /* 4052-12-31 23:59:59 */ 	if (of_device_is_compatible(op->dev.of_node, "fsl,mpc5121-rtc")) {		u32 ka;		ka = in_be32(&rtc->regs->keep_alive);		if (ka & 0x02) {			dev_warn(&op->dev,				"mpc5121-rtc: Battery or oscillator failure!\n");			out_be32(&rtc->regs->keep_alive, ka);		}		rtc->rtc->ops = &mpc5121_rtc_ops;		/*		 * This is a limitation of the driver that abuses the target		 * time register, the actual maximum year for the mpc5121 is		 * also 4052.		 */		rtc->rtc->range_min = 0;		rtc->rtc->range_max = U32_MAX;	} 	err = devm_rtc_register_device(rtc->rtc);	if (err)		goto out_dispose2; 	return 0; out_dispose2:	irq_dispose_mapping(rtc->irq_periodic);out_dispose:	irq_dispose_mapping(rtc->irq); 	return err;} static void mpc5121_rtc_remove(struct platform_device *op){	struct mpc5121_rtc_data *rtc = platform_get_drvdata(op);	struct mpc5121_rtc_regs __iomem *regs = rtc->regs; 	/* disable interrupt, so there are no nasty surprises */	out_8(&regs->alm_enable, 0);	out_8(&regs->int_enable, in_8(&regs->int_enable) & ~0x1); 	irq_dispose_mapping(rtc->irq);	irq_dispose_mapping(rtc->irq_periodic);} #ifdef CONFIG_OFstatic const struct of_device_id mpc5121_rtc_match[] = {	{ .compatible = "fsl,mpc5121-rtc", },	{ .compatible = "fsl,mpc5200-rtc", },	{},};MODULE_DEVICE_TABLE(of, mpc5121_rtc_match);#endif static struct platform_driver mpc5121_rtc_driver = {	.driver = {		.name = "mpc5121-rtc",		.of_match_table = of_match_ptr(mpc5121_rtc_match),	},	.probe = mpc5121_rtc_probe,	.remove = mpc5121_rtc_remove,}; module_platform_driver(mpc5121_rtc_driver); MODULE_DESCRIPTION("Freescale MPC5121 built-in RTC driver");MODULE_LICENSE("GPL");MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>");