1 files changed, 201 insertions, 25 deletions

diff --git a/drivers/rtc/rtc-sh.c b/drivers/rtc/rtc-sh.c
index 8f22eb1aff5c..72ba1a70f35f 100644
--- a/drivers/rtc/rtc-sh.c
+++ b/drivers/rtc/rtc-sh.c
@@ -2,6 +2,7 @@
  * 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:
  *
@@ -23,6 +24,9 @@
 #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 */
@@ -34,21 +38,25 @@
 #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             */
@@ -71,6 +79,7 @@ struct sh_rtc {
         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)
@@ -82,11 +91,16 @@ 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);
 
@@ -97,6 +111,41 @@ static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
         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);
@@ -140,10 +189,11 @@ static inline void sh_rtc_setaie(struct device *dev, unsigned int enable)
 
         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);
 
@@ -178,7 +228,7 @@ static int sh_rtc_open(struct device *dev)
                 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",
@@ -201,6 +251,7 @@ static void sh_rtc_release(struct device *dev)
         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);
@@ -345,12 +396,136 @@ static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
         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,
 };
 
@@ -443,7 +618,7 @@ static int __devexit sh_rtc_remove(struct platform_device *pdev)
 }
 static struct platform_driver sh_rtc_platform_driver = {
         .driver         = {
-                .name   = "sh-rtc",
+                .name   = DRV_NAME,
                 .owner  = THIS_MODULE,
         },
         .probe          = sh_rtc_probe,
@@ -464,5 +639,6 @@ module_init(sh_rtc_init);
 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");