* SuperH On-Chip RTC Support
*
* Copyright (C) 2006 Paul Mundt
+ * Copyright (C) 2006 Jamie Lenehan
*
* Based on the old arch/sh/kernel/cpu/rtc.c by:
*
#include <linux/spinlock.h>
#include <linux/io.h>
+#define DRV_NAME "sh-rtc"
+#define DRV_VERSION "0.1.2"
+
#ifdef CONFIG_CPU_SH3
#define rtc_reg_size sizeof(u16)
#define RTC_BIT_INVERTED 0 /* No bug on SH7708, SH7709A */
#define RTC_REG(r) ((r) * rtc_reg_size)
#define R64CNT RTC_REG(0)
-#define RSECCNT RTC_REG(1)
-#define RMINCNT RTC_REG(2)
-#define RHRCNT RTC_REG(3)
-#define RWKCNT RTC_REG(4)
-#define RDAYCNT RTC_REG(5)
-#define RMONCNT RTC_REG(6)
-#define RYRCNT RTC_REG(7)
-#define RSECAR RTC_REG(8)
-#define RMINAR RTC_REG(9)
-#define RHRAR RTC_REG(10)
-#define RWKAR RTC_REG(11)
-#define RDAYAR RTC_REG(12)
-#define RMONAR RTC_REG(13)
-#define RCR1 RTC_REG(14)
-#define RCR2 RTC_REG(15)
+
+#define RSECCNT RTC_REG(1) /* RTC sec */
+#define RMINCNT RTC_REG(2) /* RTC min */
+#define RHRCNT RTC_REG(3) /* RTC hour */
+#define RWKCNT RTC_REG(4) /* RTC week */
+#define RDAYCNT RTC_REG(5) /* RTC day */
+#define RMONCNT RTC_REG(6) /* RTC month */
+#define RYRCNT RTC_REG(7) /* RTC year */
+#define RSECAR RTC_REG(8) /* ALARM sec */
+#define RMINAR RTC_REG(9) /* ALARM min */
+#define RHRAR RTC_REG(10) /* ALARM hour */
+#define RWKAR RTC_REG(11) /* ALARM week */
+#define RDAYAR RTC_REG(12) /* ALARM day */
+#define RMONAR RTC_REG(13) /* ALARM month */
+#define RCR1 RTC_REG(14) /* Control */
+#define RCR2 RTC_REG(15) /* Control */
+
+/* ALARM Bits - or with BCD encoded value */
+#define AR_ENB 0x80 /* Enable for alarm cmp */
/* RCR1 Bits */
#define RCR1_CF 0x80 /* Carry Flag */
unsigned int alarm_irq, periodic_irq, carry_irq;
struct rtc_device *rtc_dev;
spinlock_t lock;
+ int rearm_aie;
};
static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
spin_lock(&rtc->lock);
tmp = readb(rtc->regbase + RCR1);
+ tmp &= ~RCR1_CF;
- if (tmp & RCR1_AF)
- events |= RTC_AF | RTC_IRQF;
-
- tmp &= ~(RCR1_CF | RCR1_AF);
+ if (rtc->rearm_aie) {
+ if (tmp & RCR1_AF)
+ tmp &= ~RCR1_AF; /* try to clear AF again */
+ else {
+ tmp |= RCR1_AIE; /* AF has cleared, rearm IRQ */
+ rtc->rearm_aie = 0;
+ }
+ }
writeb(tmp, rtc->regbase + RCR1);
return IRQ_HANDLED;
}
+static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
+{
+ struct platform_device *pdev = to_platform_device(dev_id);
+ struct sh_rtc *rtc = platform_get_drvdata(pdev);
+ unsigned int tmp, events = 0;
+
+ spin_lock(&rtc->lock);
+
+ tmp = readb(rtc->regbase + RCR1);
+
+ /*
+ * If AF is set then the alarm has triggered. If we clear AF while
+ * the alarm time still matches the RTC time then AF will
+ * immediately be set again, and if AIE is enabled then the alarm
+ * interrupt will immediately be retrigger. So we clear AIE here
+ * and use rtc->rearm_aie so that the carry interrupt will keep
+ * trying to clear AF and once it stays cleared it'll re-enable
+ * AIE.
+ */
+ if (tmp & RCR1_AF) {
+ events |= RTC_AF | RTC_IRQF;
+
+ tmp &= ~(RCR1_AF|RCR1_AIE);
+
+ writeb(tmp, rtc->regbase + RCR1);
+
+ rtc->rearm_aie = 1;
+
+ rtc_update_irq(&rtc->rtc_dev->class_dev, 1, events);
+ }
+
+ spin_unlock(&rtc->lock);
+ return IRQ_HANDLED;
+}
+
static irqreturn_t sh_rtc_periodic(int irq, void *dev_id)
{
struct platform_device *pdev = to_platform_device(dev_id);
tmp = readb(rtc->regbase + RCR1);
- if (enable)
- tmp |= RCR1_AIE;
- else
+ if (!enable) {
tmp &= ~RCR1_AIE;
+ rtc->rearm_aie = 0;
+ } else if (rtc->rearm_aie == 0)
+ tmp |= RCR1_AIE;
writeb(tmp, rtc->regbase + RCR1);
goto err_bad_carry;
}
- ret = request_irq(rtc->alarm_irq, sh_rtc_interrupt, IRQF_DISABLED,
+ ret = request_irq(rtc->alarm_irq, sh_rtc_alarm, IRQF_DISABLED,
"sh-rtc alarm", dev);
if (unlikely(ret)) {
dev_err(dev, "request alarm IRQ failed with %d, IRQ %d\n",
struct sh_rtc *rtc = dev_get_drvdata(dev);
sh_rtc_setpie(dev, 0);
+ sh_rtc_setaie(dev, 0);
free_irq(rtc->periodic_irq, dev);
free_irq(rtc->carry_irq, dev);
return 0;
}
+static inline int sh_rtc_read_alarm_value(struct sh_rtc *rtc, int reg_off)
+{
+ unsigned int byte;
+ int value = 0xff; /* return 0xff for ignored values */
+
+ byte = readb(rtc->regbase + reg_off);
+ if (byte & AR_ENB) {
+ byte &= ~AR_ENB; /* strip the enable bit */
+ value = BCD2BIN(byte);
+ }
+
+ return value;
+}
+
+static int sh_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sh_rtc *rtc = platform_get_drvdata(pdev);
+ struct rtc_time* tm = &wkalrm->time;
+
+ spin_lock_irq(&rtc->lock);
+
+ tm->tm_sec = sh_rtc_read_alarm_value(rtc, RSECAR);
+ tm->tm_min = sh_rtc_read_alarm_value(rtc, RMINAR);
+ tm->tm_hour = sh_rtc_read_alarm_value(rtc, RHRAR);
+ tm->tm_wday = sh_rtc_read_alarm_value(rtc, RWKAR);
+ tm->tm_mday = sh_rtc_read_alarm_value(rtc, RDAYAR);
+ tm->tm_mon = sh_rtc_read_alarm_value(rtc, RMONAR);
+ if (tm->tm_mon > 0)
+ tm->tm_mon -= 1; /* RTC is 1-12, tm_mon is 0-11 */
+ tm->tm_year = 0xffff;
+
+ spin_unlock_irq(&rtc->lock);
+
+ return 0;
+}
+
+static inline void sh_rtc_write_alarm_value(struct sh_rtc *rtc,
+ int value, int reg_off)
+{
+ /* < 0 for a value that is ignored */
+ if (value < 0)
+ writeb(0, rtc->regbase + reg_off);
+ else
+ writeb(BIN2BCD(value) | AR_ENB, rtc->regbase + reg_off);
+}
+
+static int sh_rtc_check_alarm(struct rtc_time* tm)
+{
+ /*
+ * The original rtc says anything > 0xc0 is "don't care" or "match
+ * all" - most users use 0xff but rtc-dev uses -1 for the same thing.
+ * The original rtc doesn't support years - some things use -1 and
+ * some 0xffff. We use -1 to make out tests easier.
+ */
+ if (tm->tm_year == 0xffff)
+ tm->tm_year = -1;
+ if (tm->tm_mon >= 0xff)
+ tm->tm_mon = -1;
+ if (tm->tm_mday >= 0xff)
+ tm->tm_mday = -1;
+ if (tm->tm_wday >= 0xff)
+ tm->tm_wday = -1;
+ if (tm->tm_hour >= 0xff)
+ tm->tm_hour = -1;
+ if (tm->tm_min >= 0xff)
+ tm->tm_min = -1;
+ if (tm->tm_sec >= 0xff)
+ tm->tm_sec = -1;
+
+ if (tm->tm_year > 9999 ||
+ tm->tm_mon >= 12 ||
+ tm->tm_mday == 0 || tm->tm_mday >= 32 ||
+ tm->tm_wday >= 7 ||
+ tm->tm_hour >= 24 ||
+ tm->tm_min >= 60 ||
+ tm->tm_sec >= 60)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int sh_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *wkalrm)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct sh_rtc *rtc = platform_get_drvdata(pdev);
+ unsigned int rcr1;
+ struct rtc_time *tm = &wkalrm->time;
+ int mon, err;
+
+ err = sh_rtc_check_alarm(tm);
+ if (unlikely(err < 0))
+ return err;
+
+ spin_lock_irq(&rtc->lock);
+
+ /* disable alarm interrupt and clear flag */
+ rcr1 = readb(rtc->regbase + RCR1);
+ rcr1 &= ~RCR1_AF;
+ writeb(rcr1 & ~RCR1_AIE, rtc->regbase + RCR1);
+
+ rtc->rearm_aie = 0;
+
+ /* set alarm time */
+ sh_rtc_write_alarm_value(rtc, tm->tm_sec, RSECAR);
+ sh_rtc_write_alarm_value(rtc, tm->tm_min, RMINAR);
+ sh_rtc_write_alarm_value(rtc, tm->tm_hour, RHRAR);
+ sh_rtc_write_alarm_value(rtc, tm->tm_wday, RWKAR);
+ sh_rtc_write_alarm_value(rtc, tm->tm_mday, RDAYAR);
+ mon = tm->tm_mon;
+ if (mon >= 0)
+ mon += 1;
+ sh_rtc_write_alarm_value(rtc, mon, RMONAR);
+
+ /* Restore interrupt activation status */
+ writeb(rcr1, rtc->regbase + RCR1);
+
+ spin_unlock_irq(&rtc->lock);
+
+ return 0;
+}
+
static struct rtc_class_ops sh_rtc_ops = {
.open = sh_rtc_open,
.release = sh_rtc_release,
.ioctl = sh_rtc_ioctl,
.read_time = sh_rtc_read_time,
.set_time = sh_rtc_set_time,
+ .read_alarm = sh_rtc_read_alarm,
+ .set_alarm = sh_rtc_set_alarm,
.proc = sh_rtc_proc,
};
}
static struct platform_driver sh_rtc_platform_driver = {
.driver = {
- .name = "sh-rtc",
+ .name = DRV_NAME,
.owner = THIS_MODULE,
},
.probe = sh_rtc_probe,
module_exit(sh_rtc_exit);
MODULE_DESCRIPTION("SuperH on-chip RTC driver");
-MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>, Jamie Lenehan <lenehan@twibble.org>");
MODULE_LICENSE("GPL");
projects / linux-2.6 / commitdiff