rtc: rtc-sh: Zero out tm value for invalid rtc states.
[safe/jmp/linux-2.6] / drivers / rtc / rtc-sh.c
index d2ce0c8..8e8c8b8 100644 (file)
@@ -1,7 +1,8 @@
 /*
  * SuperH On-Chip RTC Support
  *
- * Copyright (C) 2006  Paul Mundt
+ * Copyright (C) 2006, 2007  Paul Mundt
+ * Copyright (C) 2006  Jamie Lenehan
  *
  * Based on the old arch/sh/kernel/cpu/rtc.c by:
  *
 #include <linux/seq_file.h>
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
-#include <asm/io.h>
+#include <linux/io.h>
+#include <asm/rtc.h>
+
+#define DRV_NAME       "sh-rtc"
+#define DRV_VERSION    "0.1.3"
 
 #ifdef CONFIG_CPU_SH3
 #define rtc_reg_size           sizeof(u16)
 #define RTC_BIT_INVERTED       0       /* No bug on SH7708, SH7709A */
+#define RTC_DEF_CAPABILITIES   0UL
 #elif defined(CONFIG_CPU_SH4)
 #define rtc_reg_size           sizeof(u32)
 #define RTC_BIT_INVERTED       0x40    /* bug on SH7750, SH7750S */
+#define RTC_DEF_CAPABILITIES   RTC_CAP_4_DIGIT_YEAR
 #endif
 
 #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 R64CNT         RTC_REG(0)
+
+#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             */
@@ -71,39 +82,82 @@ struct sh_rtc {
        unsigned int alarm_irq, periodic_irq, carry_irq;
        struct rtc_device *rtc_dev;
        spinlock_t lock;
+       int rearm_aie;
+       unsigned long capabilities;     /* See asm-sh/rtc.h for cap bits */
 };
 
-static irqreturn_t sh_rtc_interrupt(int irq, void *id, struct pt_regs *regs)
+static irqreturn_t sh_rtc_interrupt(int irq, void *dev_id)
 {
-       struct platform_device *pdev = 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);
+       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);
 
-       rtc_update_irq(&rtc->rtc_dev->class_dev, 1, events);
+       rtc_update_irq(rtc->rtc_dev, 1, events);
 
        spin_unlock(&rtc->lock);
 
        return IRQ_HANDLED;
 }
 
-static irqreturn_t sh_rtc_periodic(int irq, void *id, struct pt_regs *regs)
+static irqreturn_t sh_rtc_alarm(int irq, void *dev_id)
 {
-       struct sh_rtc *rtc = dev_get_drvdata(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);
 
-       rtc_update_irq(&rtc->rtc_dev->class_dev, 1, RTC_PF | RTC_IRQF);
+       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, 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);
+       struct sh_rtc *rtc = platform_get_drvdata(pdev);
+
+       spin_lock(&rtc->lock);
+
+       rtc_update_irq(rtc->rtc_dev, 1, RTC_PF | RTC_IRQF);
 
        spin_unlock(&rtc->lock);
 
@@ -139,10 +193,11 @@ 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);
 
@@ -160,7 +215,7 @@ static int sh_rtc_open(struct device *dev)
        tmp |= RCR1_CIE;
        writeb(tmp, rtc->regbase + RCR1);
 
-       ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, SA_INTERRUPT,
+       ret = request_irq(rtc->periodic_irq, sh_rtc_periodic, IRQF_DISABLED,
                          "sh-rtc period", dev);
        if (unlikely(ret)) {
                dev_err(dev, "request period IRQ failed with %d, IRQ %d\n",
@@ -168,7 +223,7 @@ static int sh_rtc_open(struct device *dev)
                return ret;
        }
 
-       ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, SA_INTERRUPT,
+       ret = request_irq(rtc->carry_irq, sh_rtc_interrupt, IRQF_DISABLED,
                          "sh-rtc carry", dev);
        if (unlikely(ret)) {
                dev_err(dev, "request carry IRQ failed with %d, IRQ %d\n",
@@ -177,7 +232,7 @@ static int sh_rtc_open(struct device *dev)
                goto err_bad_carry;
        }
 
-       ret = request_irq(rtc->alarm_irq, sh_rtc_interrupt, SA_INTERRUPT,
+       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",
@@ -200,6 +255,7 @@ 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);
@@ -212,8 +268,6 @@ static int sh_rtc_proc(struct device *dev, struct seq_file *seq)
        unsigned int tmp;
 
        tmp = readb(rtc->regbase + RCR1);
-       seq_printf(seq, "alarm_IRQ\t: %s\n",
-                  (tmp & RCR1_AIE) ? "yes" : "no");
        seq_printf(seq, "carry_IRQ\t: %s\n",
                   (tmp & RCR1_CIE) ? "yes" : "no");
 
@@ -267,16 +321,16 @@ static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
                tm->tm_hour     = BCD2BIN(readb(rtc->regbase + RHRCNT));
                tm->tm_wday     = BCD2BIN(readb(rtc->regbase + RWKCNT));
                tm->tm_mday     = BCD2BIN(readb(rtc->regbase + RDAYCNT));
-               tm->tm_mon      = BCD2BIN(readb(rtc->regbase + RMONCNT));
-
-#if defined(CONFIG_CPU_SH4)
-               yr  = readw(rtc->regbase + RYRCNT);
-               yr100 = BCD2BIN(yr >> 8);
-               yr &= 0xff;
-#else
-               yr  = readb(rtc->regbase + RYRCNT);
-               yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
-#endif
+               tm->tm_mon      = BCD2BIN(readb(rtc->regbase + RMONCNT)) - 1;
+
+               if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
+                       yr  = readw(rtc->regbase + RYRCNT);
+                       yr100 = BCD2BIN(yr >> 8);
+                       yr &= 0xff;
+               } else {
+                       yr  = readb(rtc->regbase + RYRCNT);
+                       yr100 = BCD2BIN((yr == 0x99) ? 0x19 : 0x20);
+               }
 
                tm->tm_year = (yr100 * 100 + BCD2BIN(yr)) - 1900;
 
@@ -291,14 +345,16 @@ static int sh_rtc_read_time(struct device *dev, struct rtc_time *tm)
                tm->tm_sec--;
 #endif
 
-       dev_dbg(&dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
+       dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
                "mday=%d, mon=%d, year=%d, wday=%d\n",
                __FUNCTION__,
                tm->tm_sec, tm->tm_min, tm->tm_hour,
-               tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
+               tm->tm_mday, tm->tm_mon + 1, tm->tm_year, tm->tm_wday);
 
-       if (rtc_valid_tm(tm) < 0)
+       if (rtc_valid_tm(tm) < 0) {
                dev_err(dev, "invalid date\n");
+               rtc_time_to_tm(0, tm);
+       }
 
        return 0;
 }
@@ -315,6 +371,7 @@ static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
        /* Reset pre-scaler & stop RTC */
        tmp = readb(rtc->regbase + RCR2);
        tmp |= RCR2_RESET;
+       tmp &= ~RCR2_START;
        writeb(tmp, rtc->regbase + RCR2);
 
        writeb(BIN2BCD(tm->tm_sec),  rtc->regbase + RSECCNT);
@@ -322,16 +379,16 @@ static int sh_rtc_set_time(struct device *dev, struct rtc_time *tm)
        writeb(BIN2BCD(tm->tm_hour), rtc->regbase + RHRCNT);
        writeb(BIN2BCD(tm->tm_wday), rtc->regbase + RWKCNT);
        writeb(BIN2BCD(tm->tm_mday), rtc->regbase + RDAYCNT);
-       writeb(BIN2BCD(tm->tm_mon),  rtc->regbase + RMONCNT);
-
-#ifdef CONFIG_CPU_SH3
-       year = tm->tm_year % 100;
-       writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
-#else
-       year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
-               BIN2BCD(tm->tm_year % 100);
-       writew(year, rtc->regbase + RYRCNT);
-#endif
+       writeb(BIN2BCD(tm->tm_mon + 1), rtc->regbase + RMONCNT);
+
+       if (rtc->capabilities & RTC_CAP_4_DIGIT_YEAR) {
+               year = (BIN2BCD((tm->tm_year + 1900) / 100) << 8) |
+                       BIN2BCD(tm->tm_year % 100);
+               writew(year, rtc->regbase + RYRCNT);
+       } else {
+               year = tm->tm_year % 100;
+               writeb(BIN2BCD(year), rtc->regbase + RYRCNT);
+       }
 
        /* Start RTC */
        tmp = readb(rtc->regbase + RCR2);
@@ -344,12 +401,140 @@ 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;
+
+       wkalrm->enabled = (readb(rtc->regbase + RCR1) & RCR1_AIE) ? 1 : 0;
+
+       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 the alarm flag */
+       rcr1 = readb(rtc->regbase + RCR1);
+       rcr1 &= ~(RCR1_AF|RCR1_AIE);
+       writeb(rcr1, 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);
+
+       if (wkalrm->enabled) {
+               rcr1 |= RCR1_AIE;
+               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,
 };
 
@@ -405,11 +590,22 @@ static int __devinit sh_rtc_probe(struct platform_device *pdev)
 
        rtc->rtc_dev = rtc_device_register("sh", &pdev->dev,
                                           &sh_rtc_ops, THIS_MODULE);
-       if (IS_ERR(rtc)) {
+       if (IS_ERR(rtc->rtc_dev)) {
                ret = PTR_ERR(rtc->rtc_dev);
                goto err_badmap;
        }
 
+       rtc->capabilities = RTC_DEF_CAPABILITIES;
+       if (pdev->dev.platform_data) {
+               struct sh_rtc_platform_info *pinfo = pdev->dev.platform_data;
+
+               /*
+                * Some CPUs have special capabilities in addition to the
+                * default set. Add those in here.
+                */
+               rtc->capabilities |= pinfo->capabilities;
+       }
+
        platform_set_drvdata(pdev, rtc);
 
        return 0;
@@ -442,7 +638,7 @@ 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,
@@ -463,5 +659,6 @@ 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");