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path: root/drivers/rtc/rtc-mpc5121.c
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Diffstat (limited to 'drivers/rtc/rtc-mpc5121.c')
-rw-r--r--drivers/rtc/rtc-mpc5121.c411
1 files changed, 411 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c
new file mode 100644
index 000000000..6d7656a75
--- /dev/null
+++ b/drivers/rtc/rtc-mpc5121.c
@@ -0,0 +1,411 @@
+// 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_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_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, 1);
+
+ 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 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);
+
+ 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>");