rtc-m48t59: fix setting of a year on m48t08 and m48t02 rtcs
[safe/jmp/linux-2.6] / drivers / rtc / rtc-cmos.c
index 6d0c353..04ecfd2 100644 (file)
@@ -39,7 +39,6 @@
 /* this is for "generic access to PC-style RTC" using CMOS_READ/CMOS_WRITE */
 #include <asm-generic/rtc.h>
 
-
 struct cmos_rtc {
        struct rtc_device       *rtc;
        struct device           *dev;
@@ -78,6 +77,72 @@ static inline int is_intr(u8 rtc_intr)
 
 /*----------------------------------------------------------------*/
 
+/* Much modern x86 hardware has HPETs (10+ MHz timers) which, because
+ * many BIOS programmers don't set up "sane mode" IRQ routing, are mostly
+ * used in a broken "legacy replacement" mode.  The breakage includes
+ * HPET #1 hijacking the IRQ for this RTC, and being unavailable for
+ * other (better) use.
+ *
+ * When that broken mode is in use, platform glue provides a partial
+ * emulation of hardware RTC IRQ facilities using HPET #1.  We don't
+ * want to use HPET for anything except those IRQs though...
+ */
+#ifdef CONFIG_HPET_EMULATE_RTC
+#include <asm/hpet.h>
+#else
+
+static inline int is_hpet_enabled(void)
+{
+       return 0;
+}
+
+static inline int hpet_mask_rtc_irq_bit(unsigned long mask)
+{
+       return 0;
+}
+
+static inline int hpet_set_rtc_irq_bit(unsigned long mask)
+{
+       return 0;
+}
+
+static inline int
+hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
+{
+       return 0;
+}
+
+static inline int hpet_set_periodic_freq(unsigned long freq)
+{
+       return 0;
+}
+
+static inline int hpet_rtc_dropped_irq(void)
+{
+       return 0;
+}
+
+static inline int hpet_rtc_timer_init(void)
+{
+       return 0;
+}
+
+extern irq_handler_t hpet_rtc_interrupt;
+
+static inline int hpet_register_irq_handler(irq_handler_t handler)
+{
+       return 0;
+}
+
+static inline int hpet_unregister_irq_handler(irq_handler_t handler)
+{
+       return 0;
+}
+
+#endif
+
+/*----------------------------------------------------------------*/
+
 static int cmos_read_time(struct device *dev, struct rtc_time *t)
 {
        /* REVISIT:  if the clock has a "century" register, use
@@ -120,7 +185,8 @@ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
        t->time.tm_hour = CMOS_READ(RTC_HOURS_ALARM);
 
        if (cmos->day_alrm) {
-               t->time.tm_mday = CMOS_READ(cmos->day_alrm);
+               /* ignore upper bits on readback per ACPI spec */
+               t->time.tm_mday = CMOS_READ(cmos->day_alrm) & 0x3f;
                if (!t->time.tm_mday)
                        t->time.tm_mday = -1;
 
@@ -169,11 +235,56 @@ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
        return 0;
 }
 
+static void cmos_checkintr(struct cmos_rtc *cmos, unsigned char rtc_control)
+{
+       unsigned char   rtc_intr;
+
+       /* NOTE after changing RTC_xIE bits we always read INTR_FLAGS;
+        * allegedly some older rtcs need that to handle irqs properly
+        */
+       rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
+
+       if (is_hpet_enabled())
+               return;
+
+       rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
+       if (is_intr(rtc_intr))
+               rtc_update_irq(cmos->rtc, 1, rtc_intr);
+}
+
+static void cmos_irq_enable(struct cmos_rtc *cmos, unsigned char mask)
+{
+       unsigned char   rtc_control;
+
+       /* flush any pending IRQ status, notably for update irqs,
+        * before we enable new IRQs
+        */
+       rtc_control = CMOS_READ(RTC_CONTROL);
+       cmos_checkintr(cmos, rtc_control);
+
+       rtc_control |= mask;
+       CMOS_WRITE(rtc_control, RTC_CONTROL);
+       hpet_set_rtc_irq_bit(mask);
+
+       cmos_checkintr(cmos, rtc_control);
+}
+
+static void cmos_irq_disable(struct cmos_rtc *cmos, unsigned char mask)
+{
+       unsigned char   rtc_control;
+
+       rtc_control = CMOS_READ(RTC_CONTROL);
+       rtc_control &= ~mask;
+       CMOS_WRITE(rtc_control, RTC_CONTROL);
+       hpet_mask_rtc_irq_bit(mask);
+
+       cmos_checkintr(cmos, rtc_control);
+}
+
 static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 {
        struct cmos_rtc *cmos = dev_get_drvdata(dev);
        unsigned char   mon, mday, hrs, min, sec;
-       unsigned char   rtc_control, rtc_intr;
 
        if (!is_valid_irq(cmos->irq))
                return -EIO;
@@ -182,9 +293,8 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
 
        /* Writing 0xff means "don't care" or "match all".  */
 
-       mon = t->time.tm_mon;
-       mon = (mon < 12) ? BIN2BCD(mon) : 0xff;
-       mon++;
+       mon = t->time.tm_mon + 1;
+       mon = (mon <= 12) ? BIN2BCD(mon) : 0xff;
 
        mday = t->time.tm_mday;
        mday = (mday >= 1 && mday <= 31) ? BIN2BCD(mday) : 0xff;
@@ -201,13 +311,7 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
        spin_lock_irq(&rtc_lock);
 
        /* next rtc irq must not be from previous alarm setting */
-       rtc_control = CMOS_READ(RTC_CONTROL);
-       rtc_control &= ~RTC_AIE;
-       CMOS_WRITE(rtc_control, RTC_CONTROL);
-       rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
-       rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
-       if (is_intr(rtc_intr))
-               rtc_update_irq(cmos->rtc, 1, rtc_intr);
+       cmos_irq_disable(cmos, RTC_AIE);
 
        /* update alarm */
        CMOS_WRITE(hrs, RTC_HOURS_ALARM);
@@ -221,14 +325,13 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
                        CMOS_WRITE(mon, cmos->mon_alrm);
        }
 
-       if (t->enabled) {
-               rtc_control |= RTC_AIE;
-               CMOS_WRITE(rtc_control, RTC_CONTROL);
-               rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
-               rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
-               if (is_intr(rtc_intr))
-                       rtc_update_irq(cmos->rtc, 1, rtc_intr);
-       }
+       /* FIXME the HPET alarm glue currently ignores day_alrm
+        * and mon_alrm ...
+        */
+       hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, t->time.tm_sec);
+
+       if (t->enabled)
+               cmos_irq_enable(cmos, RTC_AIE);
 
        spin_unlock_irq(&rtc_lock);
 
@@ -251,6 +354,7 @@ static int cmos_irq_set_freq(struct device *dev, int freq)
        f = 16 - f;
 
        spin_lock_irqsave(&rtc_lock, flags);
+       hpet_set_periodic_freq(freq);
        CMOS_WRITE(RTC_REF_CLCK_32KHZ | f, RTC_FREQ_SELECT);
        spin_unlock_irqrestore(&rtc_lock, flags);
 
@@ -260,26 +364,17 @@ static int cmos_irq_set_freq(struct device *dev, int freq)
 static int cmos_irq_set_state(struct device *dev, int enabled)
 {
        struct cmos_rtc *cmos = dev_get_drvdata(dev);
-       unsigned char   rtc_control, rtc_intr;
        unsigned long   flags;
 
        if (!is_valid_irq(cmos->irq))
                return -ENXIO;
 
        spin_lock_irqsave(&rtc_lock, flags);
-       rtc_control = CMOS_READ(RTC_CONTROL);
 
        if (enabled)
-               rtc_control |= RTC_PIE;
+               cmos_irq_enable(cmos, RTC_PIE);
        else
-               rtc_control &= ~RTC_PIE;
-
-       CMOS_WRITE(rtc_control, RTC_CONTROL);
-
-       rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
-       rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
-       if (is_intr(rtc_intr))
-               rtc_update_irq(cmos->rtc, 1, rtc_intr);
+               cmos_irq_disable(cmos, RTC_PIE);
 
        spin_unlock_irqrestore(&rtc_lock, flags);
        return 0;
@@ -291,7 +386,6 @@ static int
 cmos_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
 {
        struct cmos_rtc *cmos = dev_get_drvdata(dev);
-       unsigned char   rtc_control, rtc_intr;
        unsigned long   flags;
 
        switch (cmd) {
@@ -299,42 +393,29 @@ cmos_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
        case RTC_AIE_ON:
        case RTC_UIE_OFF:
        case RTC_UIE_ON:
-       case RTC_PIE_OFF:
-       case RTC_PIE_ON:
                if (!is_valid_irq(cmos->irq))
                        return -EINVAL;
                break;
+       /* PIE ON/OFF is handled by cmos_irq_set_state() */
        default:
                return -ENOIOCTLCMD;
        }
 
        spin_lock_irqsave(&rtc_lock, flags);
-       rtc_control = CMOS_READ(RTC_CONTROL);
        switch (cmd) {
        case RTC_AIE_OFF:       /* alarm off */
-               rtc_control &= ~RTC_AIE;
+               cmos_irq_disable(cmos, RTC_AIE);
                break;
        case RTC_AIE_ON:        /* alarm on */
-               rtc_control |= RTC_AIE;
+               cmos_irq_enable(cmos, RTC_AIE);
                break;
        case RTC_UIE_OFF:       /* update off */
-               rtc_control &= ~RTC_UIE;
+               cmos_irq_disable(cmos, RTC_UIE);
                break;
        case RTC_UIE_ON:        /* update on */
-               rtc_control |= RTC_UIE;
-               break;
-       case RTC_PIE_OFF:       /* periodic off */
-               rtc_control &= ~RTC_PIE;
-               break;
-       case RTC_PIE_ON:        /* periodic on */
-               rtc_control |= RTC_PIE;
+               cmos_irq_enable(cmos, RTC_UIE);
                break;
        }
-       CMOS_WRITE(rtc_control, RTC_CONTROL);
-       rtc_intr = CMOS_READ(RTC_INTR_FLAGS);
-       rtc_intr &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
-       if (is_intr(rtc_intr))
-               rtc_update_irq(cmos->rtc, 1, rtc_intr);
        spin_unlock_irqrestore(&rtc_lock, flags);
        return 0;
 }
@@ -361,6 +442,7 @@ static int cmos_procfs(struct device *dev, struct seq_file *seq)
        return seq_printf(seq,
                        "periodic_IRQ\t: %s\n"
                        "update_IRQ\t: %s\n"
+                       "HPET_emulated\t: %s\n"
                        // "square_wave\t: %s\n"
                        // "BCD\t\t: %s\n"
                        "DST_enable\t: %s\n"
@@ -368,6 +450,7 @@ static int cmos_procfs(struct device *dev, struct seq_file *seq)
                        "batt_status\t: %s\n",
                        (rtc_control & RTC_PIE) ? "yes" : "no",
                        (rtc_control & RTC_UIE) ? "yes" : "no",
+                       is_hpet_enabled() ? "yes" : "no",
                        // (rtc_control & RTC_SQWE) ? "yes" : "no",
                        // (rtc_control & RTC_DM_BINARY) ? "no" : "yes",
                        (rtc_control & RTC_DST_EN) ? "yes" : "no",
@@ -392,15 +475,113 @@ static const struct rtc_class_ops cmos_rtc_ops = {
 
 /*----------------------------------------------------------------*/
 
+/*
+ * All these chips have at least 64 bytes of address space, shared by
+ * RTC registers and NVRAM.  Most of those bytes of NVRAM are used
+ * by boot firmware.  Modern chips have 128 or 256 bytes.
+ */
+
+#define NVRAM_OFFSET   (RTC_REG_D + 1)
+
+static ssize_t
+cmos_nvram_read(struct kobject *kobj, struct bin_attribute *attr,
+               char *buf, loff_t off, size_t count)
+{
+       int     retval;
+
+       if (unlikely(off >= attr->size))
+               return 0;
+       if ((off + count) > attr->size)
+               count = attr->size - off;
+
+       spin_lock_irq(&rtc_lock);
+       for (retval = 0, off += NVRAM_OFFSET; count--; retval++, off++)
+               *buf++ = CMOS_READ(off);
+       spin_unlock_irq(&rtc_lock);
+
+       return retval;
+}
+
+static ssize_t
+cmos_nvram_write(struct kobject *kobj, struct bin_attribute *attr,
+               char *buf, loff_t off, size_t count)
+{
+       struct cmos_rtc *cmos;
+       int             retval;
+
+       cmos = dev_get_drvdata(container_of(kobj, struct device, kobj));
+       if (unlikely(off >= attr->size))
+               return -EFBIG;
+       if ((off + count) > attr->size)
+               count = attr->size - off;
+
+       /* NOTE:  on at least PCs and Ataris, the boot firmware uses a
+        * checksum on part of the NVRAM data.  That's currently ignored
+        * here.  If userspace is smart enough to know what fields of
+        * NVRAM to update, updating checksums is also part of its job.
+        */
+       spin_lock_irq(&rtc_lock);
+       for (retval = 0, off += NVRAM_OFFSET; count--; retval++, off++) {
+               /* don't trash RTC registers */
+               if (off == cmos->day_alrm
+                               || off == cmos->mon_alrm
+                               || off == cmos->century)
+                       buf++;
+               else
+                       CMOS_WRITE(*buf++, off);
+       }
+       spin_unlock_irq(&rtc_lock);
+
+       return retval;
+}
+
+static struct bin_attribute nvram = {
+       .attr = {
+               .name   = "nvram",
+               .mode   = S_IRUGO | S_IWUSR,
+               .owner  = THIS_MODULE,
+       },
+
+       .read   = cmos_nvram_read,
+       .write  = cmos_nvram_write,
+       /* size gets set up later */
+};
+
+/*----------------------------------------------------------------*/
+
 static struct cmos_rtc cmos_rtc;
 
 static irqreturn_t cmos_interrupt(int irq, void *p)
 {
        u8              irqstat;
+       u8              rtc_control;
 
        spin_lock(&rtc_lock);
+
+       /* When the HPET interrupt handler calls us, the interrupt
+        * status is passed as arg1 instead of the irq number.  But
+        * always clear irq status, even when HPET is in the way.
+        *
+        * Note that HPET and RTC are almost certainly out of phase,
+        * giving different IRQ status ...
+        */
        irqstat = CMOS_READ(RTC_INTR_FLAGS);
-       irqstat &= (CMOS_READ(RTC_CONTROL) & RTC_IRQMASK) | RTC_IRQF;
+       rtc_control = CMOS_READ(RTC_CONTROL);
+       if (is_hpet_enabled())
+               irqstat = (unsigned long)irq & 0xF0;
+       irqstat &= (rtc_control & RTC_IRQMASK) | RTC_IRQF;
+
+       /* All Linux RTC alarms should be treated as if they were oneshot.
+        * Similar code may be needed in system wakeup paths, in case the
+        * alarm woke the system.
+        */
+       if (irqstat & RTC_AIE) {
+               rtc_control &= ~RTC_AIE;
+               CMOS_WRITE(rtc_control, RTC_CONTROL);
+               hpet_mask_rtc_irq_bit(RTC_AIE);
+
+               CMOS_READ(RTC_INTR_FLAGS);
+       }
        spin_unlock(&rtc_lock);
 
        if (is_intr(irqstat)) {
@@ -411,11 +592,9 @@ static irqreturn_t cmos_interrupt(int irq, void *p)
 }
 
 #ifdef CONFIG_PNP
-#define        is_pnp()        1
 #define        INITSECTION
 
 #else
-#define        is_pnp()        0
 #define        INITSECTION     __init
 #endif
 
@@ -425,6 +604,7 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
        struct cmos_rtc_board_info      *info = dev->platform_data;
        int                             retval = 0;
        unsigned char                   rtc_control;
+       unsigned                        address_space;
 
        /* there can be only one ... */
        if (cmos_rtc.dev)
@@ -433,18 +613,52 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
        if (!ports)
                return -ENODEV;
 
+       /* Claim I/O ports ASAP, minimizing conflict with legacy driver.
+        *
+        * REVISIT non-x86 systems may instead use memory space resources
+        * (needing ioremap etc), not i/o space resources like this ...
+        */
+       ports = request_region(ports->start,
+                       ports->end + 1 - ports->start,
+                       driver_name);
+       if (!ports) {
+               dev_dbg(dev, "i/o registers already in use\n");
+               return -EBUSY;
+       }
+
        cmos_rtc.irq = rtc_irq;
        cmos_rtc.iomem = ports;
 
+       /* Heuristic to deduce NVRAM size ... do what the legacy NVRAM
+        * driver did, but don't reject unknown configs.   Old hardware
+        * won't address 128 bytes, and for now we ignore the way newer
+        * chips can address 256 bytes (using two more i/o ports).
+        */
+#if    defined(CONFIG_ATARI)
+       address_space = 64;
+#elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__sparc__)
+       address_space = 128;
+#else
+#warning Assuming 128 bytes of RTC+NVRAM address space, not 64 bytes.
+       address_space = 128;
+#endif
+
        /* For ACPI systems extension info comes from the FADT.  On others,
         * board specific setup provides it as appropriate.  Systems where
         * the alarm IRQ isn't automatically a wakeup IRQ (like ACPI, and
         * some almost-clones) can provide hooks to make that behave.
+        *
+        * Note that ACPI doesn't preclude putting these registers into
+        * "extended" areas of the chip, including some that we won't yet
+        * expect CMOS_READ and friends to handle.
         */
        if (info) {
-               cmos_rtc.day_alrm = info->rtc_day_alarm;
-               cmos_rtc.mon_alrm = info->rtc_mon_alarm;
-               cmos_rtc.century = info->rtc_century;
+               if (info->rtc_day_alarm && info->rtc_day_alarm < 128)
+                       cmos_rtc.day_alrm = info->rtc_day_alarm;
+               if (info->rtc_mon_alarm && info->rtc_mon_alarm < 128)
+                       cmos_rtc.mon_alrm = info->rtc_mon_alarm;
+               if (info->rtc_century && info->rtc_century < 128)
+                       cmos_rtc.century = info->rtc_century;
 
                if (info->wake_on && info->wake_off) {
                        cmos_rtc.wake_on = info->wake_on;
@@ -454,24 +668,13 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
 
        cmos_rtc.rtc = rtc_device_register(driver_name, dev,
                                &cmos_rtc_ops, THIS_MODULE);
-       if (IS_ERR(cmos_rtc.rtc))
-               return PTR_ERR(cmos_rtc.rtc);
+       if (IS_ERR(cmos_rtc.rtc)) {
+               retval = PTR_ERR(cmos_rtc.rtc);
+               goto cleanup0;
+       }
 
        cmos_rtc.dev = dev;
        dev_set_drvdata(dev, &cmos_rtc);
-
-       /* platform and pnp busses handle resources incompatibly.
-        *
-        * REVISIT for non-x86 systems we may need to handle io memory
-        * resources: ioremap them, and request_mem_region().
-        */
-       if (is_pnp()) {
-               retval = request_resource(&ioport_resource, ports);
-               if (retval < 0) {
-                       dev_dbg(dev, "i/o registers already in use\n");
-                       goto cleanup0;
-               }
-       }
        rename_region(ports, cmos_rtc.rtc->dev.bus_id);
 
        spin_lock_irq(&rtc_lock);
@@ -482,45 +685,62 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
         * doesn't use 32KHz here ... for portability we might need to
         * do something about other clock frequencies.
         */
-       CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
        cmos_rtc.rtc->irq_freq = 1024;
+       hpet_set_periodic_freq(cmos_rtc.rtc->irq_freq);
+       CMOS_WRITE(RTC_REF_CLCK_32KHZ | 0x06, RTC_FREQ_SELECT);
+
+       /* disable irqs */
+       cmos_irq_disable(&cmos_rtc, RTC_PIE | RTC_AIE | RTC_UIE);
 
-       /* disable irqs.
-        *
-        * NOTE after changing RTC_xIE bits we always read INTR_FLAGS;
-        * allegedly some older rtcs need that to handle irqs properly
-        */
        rtc_control = CMOS_READ(RTC_CONTROL);
-       rtc_control &= ~(RTC_PIE | RTC_AIE | RTC_UIE);
-       CMOS_WRITE(rtc_control, RTC_CONTROL);
-       CMOS_READ(RTC_INTR_FLAGS);
 
        spin_unlock_irq(&rtc_lock);
 
        /* FIXME teach the alarm code how to handle binary mode;
         * <asm-generic/rtc.h> doesn't know 12-hour mode either.
         */
-       if (!(rtc_control & RTC_24H) || (rtc_control & (RTC_DM_BINARY))) {
+       if (is_valid_irq(rtc_irq) &&
+           (!(rtc_control & RTC_24H) || (rtc_control & (RTC_DM_BINARY)))) {
                dev_dbg(dev, "only 24-hr BCD mode supported\n");
                retval = -ENXIO;
                goto cleanup1;
        }
 
-       if (is_valid_irq(rtc_irq))
-               retval = request_irq(rtc_irq, cmos_interrupt, IRQF_DISABLED,
-                               cmos_rtc.rtc->dev.bus_id,
+       if (is_valid_irq(rtc_irq)) {
+               irq_handler_t rtc_cmos_int_handler;
+
+               if (is_hpet_enabled()) {
+                       int err;
+
+                       rtc_cmos_int_handler = hpet_rtc_interrupt;
+                       err = hpet_register_irq_handler(cmos_interrupt);
+                       if (err != 0) {
+                               printk(KERN_WARNING "hpet_register_irq_handler "
+                                               " failed in rtc_init().");
+                               goto cleanup1;
+                       }
+               } else
+                       rtc_cmos_int_handler = cmos_interrupt;
+
+               retval = request_irq(rtc_irq, rtc_cmos_int_handler,
+                               IRQF_DISABLED, cmos_rtc.rtc->dev.bus_id,
                                cmos_rtc.rtc);
-       if (retval < 0) {
-               dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
-               goto cleanup1;
+               if (retval < 0) {
+                       dev_dbg(dev, "IRQ %d is already in use\n", rtc_irq);
+                       goto cleanup1;
+               }
        }
+       hpet_rtc_timer_init();
 
-       /* REVISIT optionally make 50 or 114 bytes NVRAM available,
-        * like rtc-ds1553, rtc-ds1742 ... this will often include
-        * registers for century, and day/month alarm.
-        */
+       /* export at least the first block of NVRAM */
+       nvram.size = address_space - NVRAM_OFFSET;
+       retval = sysfs_create_bin_file(&dev->kobj, &nvram);
+       if (retval < 0) {
+               dev_dbg(dev, "can't create nvram file? %d\n", retval);
+               goto cleanup2;
+       }
 
-       pr_info("%s: alarms up to one %s%s\n",
+       pr_info("%s: alarms up to one %s%s%s\n",
                        cmos_rtc.rtc->dev.bus_id,
                        is_valid_irq(rtc_irq)
                                ?  (cmos_rtc.mon_alrm
@@ -528,46 +748,51 @@ cmos_do_probe(struct device *dev, struct resource *ports, int rtc_irq)
                                        : (cmos_rtc.day_alrm
                                                ? "month" : "day"))
                                : "no",
-                       cmos_rtc.century ? ", y3k" : ""
-                       );
+                       cmos_rtc.century ? ", y3k" : "",
+                       is_hpet_enabled() ? ", hpet irqs" : "");
 
        return 0;
 
+cleanup2:
+       if (is_valid_irq(rtc_irq))
+               free_irq(rtc_irq, cmos_rtc.rtc);
 cleanup1:
-       rename_region(ports, NULL);
-cleanup0:
+       cmos_rtc.dev = NULL;
        rtc_device_unregister(cmos_rtc.rtc);
+cleanup0:
+       release_region(ports->start, ports->end + 1 - ports->start);
        return retval;
 }
 
 static void cmos_do_shutdown(void)
 {
-       unsigned char   rtc_control;
-
        spin_lock_irq(&rtc_lock);
-       rtc_control = CMOS_READ(RTC_CONTROL);
-       rtc_control &= ~(RTC_PIE|RTC_AIE|RTC_UIE);
-       CMOS_WRITE(rtc_control, RTC_CONTROL);
-       CMOS_READ(RTC_INTR_FLAGS);
+       cmos_irq_disable(&cmos_rtc, RTC_IRQMASK);
        spin_unlock_irq(&rtc_lock);
 }
 
 static void __exit cmos_do_remove(struct device *dev)
 {
        struct cmos_rtc *cmos = dev_get_drvdata(dev);
+       struct resource *ports;
 
        cmos_do_shutdown();
 
-       if (is_pnp())
-               release_resource(cmos->iomem);
-       rename_region(cmos->iomem, NULL);
+       sysfs_remove_bin_file(&dev->kobj, &nvram);
+
+       if (is_valid_irq(cmos->irq)) {
+               free_irq(cmos->irq, cmos->rtc);
+               hpet_unregister_irq_handler(cmos_interrupt);
+       }
 
-       if (is_valid_irq(cmos->irq))
-               free_irq(cmos->irq, cmos_rtc.rtc);
+       rtc_device_unregister(cmos->rtc);
+       cmos->rtc = NULL;
 
-       rtc_device_unregister(cmos_rtc.rtc);
+       ports = cmos->iomem;
+       release_region(ports->start, ports->end + 1 - ports->start);
+       cmos->iomem = NULL;
 
-       cmos_rtc.dev = NULL;
+       cmos->dev = NULL;
        dev_set_drvdata(dev, NULL);
 }
 
@@ -583,17 +808,17 @@ static int cmos_suspend(struct device *dev, pm_message_t mesg)
        spin_lock_irq(&rtc_lock);
        cmos->suspend_ctrl = tmp = CMOS_READ(RTC_CONTROL);
        if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
-               unsigned char   irqstat;
+               unsigned char   mask;
 
                if (do_wake)
-                       tmp &= ~(RTC_PIE|RTC_UIE);
+                       mask = RTC_IRQMASK & ~RTC_AIE;
                else
-                       tmp &= ~(RTC_PIE|RTC_AIE|RTC_UIE);
+                       mask = RTC_IRQMASK;
+               tmp &= ~mask;
                CMOS_WRITE(tmp, RTC_CONTROL);
-               irqstat = CMOS_READ(RTC_INTR_FLAGS);
-               irqstat &= (tmp & RTC_IRQMASK) | RTC_IRQF;
-               if (is_intr(irqstat))
-                       rtc_update_irq(cmos->rtc, 1, irqstat);
+               hpet_mask_rtc_irq_bit(mask);
+
+               cmos_checkintr(cmos, tmp);
        }
        spin_unlock_irq(&rtc_lock);
 
@@ -619,7 +844,8 @@ static int cmos_resume(struct device *dev)
        unsigned char   tmp = cmos->suspend_ctrl;
 
        /* re-enable any irqs previously active */
-       if (tmp & (RTC_PIE|RTC_AIE|RTC_UIE)) {
+       if (tmp & RTC_IRQMASK) {
+               unsigned char   mask;
 
                if (cmos->enabled_wake) {
                        if (cmos->wake_off)
@@ -630,18 +856,28 @@ static int cmos_resume(struct device *dev)
                }
 
                spin_lock_irq(&rtc_lock);
-               CMOS_WRITE(tmp, RTC_CONTROL);
-               tmp = CMOS_READ(RTC_INTR_FLAGS);
-               tmp &= (cmos->suspend_ctrl & RTC_IRQMASK) | RTC_IRQF;
-               if (is_intr(tmp))
-                       rtc_update_irq(cmos->rtc, 1, tmp);
+               do {
+                       CMOS_WRITE(tmp, RTC_CONTROL);
+                       hpet_set_rtc_irq_bit(tmp & RTC_IRQMASK);
+
+                       mask = CMOS_READ(RTC_INTR_FLAGS);
+                       mask &= (tmp & RTC_IRQMASK) | RTC_IRQF;
+                       if (!is_hpet_enabled() || !is_intr(mask))
+                               break;
+
+                       /* force one-shot behavior if HPET blocked
+                        * the wake alarm's irq
+                        */
+                       rtc_update_irq(cmos->rtc, 1, mask);
+                       tmp &= ~RTC_AIE;
+                       hpet_mask_rtc_irq_bit(RTC_AIE);
+               } while (mask & RTC_AIE);
                spin_unlock_irq(&rtc_lock);
        }
 
        pr_debug("%s: resume, ctrl %02x\n",
                        cmos_rtc.rtc->dev.bus_id,
-                       cmos->suspend_ctrl);
-
+                       tmp);
 
        return 0;
 }
@@ -653,8 +889,12 @@ static int cmos_resume(struct device *dev)
 
 /*----------------------------------------------------------------*/
 
-/* The "CMOS" RTC normally lives on the platform_bus.  On ACPI systems,
- * the device node will always be created as a PNPACPI device.
+/* On non-x86 systems, a "CMOS" RTC lives most naturally on platform_bus.
+ * ACPI systems always list these as PNPACPI devices, and pre-ACPI PCs
+ * probably list them in similar PNPBIOS tables; so PNP is more common.
+ *
+ * We don't use legacy "poke at the hardware" probing.  Ancient PCs that
+ * predate even PNPBIOS should set up platform_bus devices.
  */
 
 #ifdef CONFIG_PNP
@@ -673,11 +913,12 @@ cmos_pnp_probe(struct pnp_dev *pnp, const struct pnp_device_id *id)
                 * don't define the IRQ. It should always be safe to
                 * hardcode it in these cases
                 */
-               return cmos_do_probe(&pnp->dev, &pnp->res.port_resource[0], 8);
+               return cmos_do_probe(&pnp->dev,
+                               pnp_get_resource(pnp, IORESOURCE_IO, 0), 8);
        else
                return cmos_do_probe(&pnp->dev,
-                                    &pnp->res.port_resource[0],
-                                    pnp->res.irq_resource[0].start);
+                               pnp_get_resource(pnp, IORESOURCE_IO, 0),
+                               pnp_irq(pnp, 0));
 }
 
 static void __exit cmos_pnp_remove(struct pnp_dev *pnp)
@@ -723,19 +964,7 @@ static struct pnp_driver cmos_pnp_driver = {
        .resume         = cmos_pnp_resume,
 };
 
-static int __init cmos_init(void)
-{
-       return pnp_register_driver(&cmos_pnp_driver);
-}
-module_init(cmos_init);
-
-static void __exit cmos_exit(void)
-{
-       pnp_unregister_driver(&cmos_pnp_driver);
-}
-module_exit(cmos_exit);
-
-#else  /* no PNP */
+#endif /* CONFIG_PNP */
 
 /*----------------------------------------------------------------*/
 
@@ -761,6 +990,9 @@ static void cmos_platform_shutdown(struct platform_device *pdev)
        cmos_do_shutdown();
 }
 
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:rtc_cmos");
+
 static struct platform_driver cmos_platform_driver = {
        .remove         = __exit_p(cmos_platform_remove),
        .shutdown       = cmos_platform_shutdown,
@@ -773,20 +1005,33 @@ static struct platform_driver cmos_platform_driver = {
 
 static int __init cmos_init(void)
 {
+#ifdef CONFIG_PNP
+       if (pnp_platform_devices)
+               return pnp_register_driver(&cmos_pnp_driver);
+       else
+               return platform_driver_probe(&cmos_platform_driver,
+                       cmos_platform_probe);
+#else
        return platform_driver_probe(&cmos_platform_driver,
                        cmos_platform_probe);
+#endif /* CONFIG_PNP */
 }
 module_init(cmos_init);
 
 static void __exit cmos_exit(void)
 {
+#ifdef CONFIG_PNP
+       if (pnp_platform_devices)
+               pnp_unregister_driver(&cmos_pnp_driver);
+       else
+               platform_driver_unregister(&cmos_platform_driver);
+#else
        platform_driver_unregister(&cmos_platform_driver);
+#endif /* CONFIG_PNP */
 }
 module_exit(cmos_exit);
 
 
-#endif /* !PNP */
-
 MODULE_AUTHOR("David Brownell");
 MODULE_DESCRIPTION("Driver for PC-style 'CMOS' RTCs");
 MODULE_LICENSE("GPL");