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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.c387
1 files changed, 387 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c
new file mode 100644
index 00000000000..4313ca03a96
--- /dev/null
+++ b/drivers/rtc/rtc-mpc5121.c
@@ -0,0 +1,387 @@
+/*
+ * Real-time clock driver for MPC5121
+ *
+ * Copyright 2007, Domen Puncer <domen.puncer@telargo.com>
+ * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * 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_device.h>
+#include <linux/of_platform.h>
+#include <linux/io.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 rtc_valid_tm(tm);
+}
+
+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 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 int mpc5121_rtc_update_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;
+
+ val = in_8(&regs->int_enable);
+
+ if (enabled)
+ val = (val & ~0x8) | 0x1;
+ else
+ val &= ~0x1;
+
+ out_8(&regs->int_enable, 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,
+ .update_irq_enable = mpc5121_rtc_update_irq_enable,
+};
+
+static int __devinit mpc5121_rtc_probe(struct of_device *op,
+ const struct of_device_id *match)
+{
+ struct mpc5121_rtc_data *rtc;
+ int err = 0;
+ u32 ka;
+
+ rtc = kzalloc(sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ rtc->regs = of_iomap(op->node, 0);
+ if (!rtc->regs) {
+ dev_err(&op->dev, "%s: couldn't map io space\n", __func__);
+ err = -ENOSYS;
+ goto out_free;
+ }
+
+ device_init_wakeup(&op->dev, 1);
+
+ dev_set_drvdata(&op->dev, rtc);
+
+ rtc->irq = irq_of_parse_and_map(op->node, 1);
+ err = request_irq(rtc->irq, mpc5121_rtc_handler, IRQF_DISABLED,
+ "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->node, 0);
+ err = request_irq(rtc->irq_periodic, mpc5121_rtc_handler_upd,
+ IRQF_DISABLED, "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;
+ }
+
+ 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 = rtc_device_register("mpc5121-rtc", &op->dev,
+ &mpc5121_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc->rtc)) {
+ err = PTR_ERR(rtc->rtc);
+ goto out_free_irq;
+ }
+
+ 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);
+out_free:
+ kfree(rtc);
+
+ return err;
+}
+
+static int __devexit mpc5121_rtc_remove(struct of_device *op)
+{
+ struct mpc5121_rtc_data *rtc = dev_get_drvdata(&op->dev);
+ 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);
+
+ rtc_device_unregister(rtc->rtc);
+ 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);
+ dev_set_drvdata(&op->dev, NULL);
+ kfree(rtc);
+
+ return 0;
+}
+
+static struct of_device_id mpc5121_rtc_match[] __devinitdata = {
+ { .compatible = "fsl,mpc5121-rtc", },
+ {},
+};
+
+static struct of_platform_driver mpc5121_rtc_driver = {
+ .owner = THIS_MODULE,
+ .name = "mpc5121-rtc",
+ .match_table = mpc5121_rtc_match,
+ .probe = mpc5121_rtc_probe,
+ .remove = __devexit_p(mpc5121_rtc_remove),
+};
+
+static int __init mpc5121_rtc_init(void)
+{
+ return of_register_platform_driver(&mpc5121_rtc_driver);
+}
+module_init(mpc5121_rtc_init);
+
+static void __exit mpc5121_rtc_exit(void)
+{
+ of_unregister_platform_driver(&mpc5121_rtc_driver);
+}
+module_exit(mpc5121_rtc_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>");