v4.19.13 snapshot.
diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c
new file mode 100644
index 0000000..dd03642
--- /dev/null
+++ b/drivers/rtc/rtc-mpc5121.c
@@ -0,0 +1,424 @@
+/*
+ * 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
+ *
+ * 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/init.h>
+#include <linux/module.h>
+#include <linux/rtc.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.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_time_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;
+	int ret;
+	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.
+	 */
+	ret = rtc_tm_to_time(tm, &now);
+	if (ret == 0)
+		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;
+
+	/*
+	 * the alarm has no seconds so deal with it
+	 */
+	if (alarm->time.tm_sec) {
+		alarm->time.tm_sec = 0;
+		alarm->time.tm_min++;
+		if (alarm->time.tm_min >= 60) {
+			alarm->time.tm_min = 0;
+			alarm->time.tm_hour++;
+			if (alarm->time.tm_hour >= 24)
+				alarm->time.tm_hour = 0;
+		}
+	}
+
+	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 = of_iomap(op->dev.of_node, 0);
+	if (!rtc->regs) {
+		dev_err(&op->dev, "%s: couldn't map io space\n", __func__);
+		return -ENOSYS;
+	}
+
+	device_init_wakeup(&op->dev, 1);
+
+	platform_set_drvdata(op, rtc);
+
+	rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1);
+	err = request_irq(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 = request_irq(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;
+	}
+
+	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 = devm_rtc_device_register(&op->dev, "mpc5121-rtc",
+						&mpc5121_rtc_ops, THIS_MODULE);
+	} else {
+		rtc->rtc = devm_rtc_device_register(&op->dev, "mpc5200-rtc",
+						&mpc5200_rtc_ops, THIS_MODULE);
+	}
+
+	if (IS_ERR(rtc->rtc)) {
+		err = PTR_ERR(rtc->rtc);
+		goto out_free_irq;
+	}
+	rtc->rtc->uie_unsupported = 1;
+
+	return 0;
+
+out_free_irq:
+	free_irq(rtc->irq_periodic, &op->dev);
+out_dispose2:
+	irq_dispose_mapping(rtc->irq_periodic);
+	free_irq(rtc->irq, &op->dev);
+out_dispose:
+	irq_dispose_mapping(rtc->irq);
+	iounmap(rtc->regs);
+
+	return err;
+}
+
+static int 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);
+
+	iounmap(rtc->regs);
+	free_irq(rtc->irq, &op->dev);
+	free_irq(rtc->irq_periodic, &op->dev);
+	irq_dispose_mapping(rtc->irq);
+	irq_dispose_mapping(rtc->irq_periodic);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static 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_LICENSE("GPL");
+MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>");