rtc: Add MPC5121 Real time clock driver
authorAnatolij Gustschin <agust@denx.de>
Tue, 16 Feb 2010 17:47:35 +0000 (10:47 -0700)
committerGrant Likely <grant.likely@secretlab.ca>
Tue, 16 Feb 2010 17:47:35 +0000 (10:47 -0700)
Add support for MPC5121 real time clock module.

Signed-off-by: John Rigby <jcrigby@gmail.com>
Signed-off-by: Piotr Ziecik <kosmo@semihalf.com>
Signed-off-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
drivers/rtc/Kconfig
drivers/rtc/Makefile
drivers/rtc/rtc-mpc5121.c [new file with mode: 0644]

index 8167e9e..2bb8a8b 100644 (file)
@@ -868,4 +868,14 @@ config RTC_DRV_MC13783
        help
          This enables support for the Freescale MC13783 PMIC RTC
 
+config RTC_DRV_MPC5121
+       tristate "Freescale MPC5121 built-in RTC"
+       depends on PPC_MPC512x && RTC_CLASS
+       help
+         If you say yes here you will get support for the
+         built-in RTC MPC5121.
+
+         This driver can also be built as a module. If so, the module
+         will be called rtc-mpc5121.
+
 endif # RTC_CLASS
index e5160fd..b7148af 100644 (file)
@@ -55,6 +55,7 @@ obj-$(CONFIG_RTC_DRV_MAX6900) += rtc-max6900.o
 obj-$(CONFIG_RTC_DRV_MAX6902)  += rtc-max6902.o
 obj-$(CONFIG_RTC_DRV_MC13783)  += rtc-mc13783.o
 obj-$(CONFIG_RTC_DRV_MSM6242)  += rtc-msm6242.o
+obj-$(CONFIG_RTC_DRV_MPC5121)  += rtc-mpc5121.o
 obj-$(CONFIG_RTC_DRV_MV)       += rtc-mv.o
 obj-$(CONFIG_RTC_DRV_NUC900)   += rtc-nuc900.o
 obj-$(CONFIG_RTC_DRV_OMAP)     += rtc-omap.o
diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c
new file mode 100644 (file)
index 0000000..4313ca0
--- /dev/null
@@ -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>");