1 files changed, 61 insertions, 12 deletions

diff --git a/drivers/rtc/rtc-at91sam9.c b/drivers/rtc/rtc-at91sam9.c
index 2183fd2750ab..5ccaee32df72 100644
--- a/drivers/rtc/rtc-at91sam9.c
+++ b/drivers/rtc/rtc-at91sam9.c
@@ -23,6 +23,7 @@
 #include <linux/io.h>
 #include <linux/mfd/syscon.h>
 #include <linux/regmap.h>
+#include <linux/suspend.h>
 #include <linux/clk.h>
 
 /*
@@ -77,6 +78,9 @@ struct sam9_rtc {
         unsigned int            gpbr_offset;
         int                     irq;
         struct clk              *sclk;
+        bool                    suspended;
+        unsigned long           events;
+        spinlock_t              lock;
 };
 
 #define rtt_readl(rtc, field) \
@@ -271,14 +275,9 @@ static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
         return 0;
 }
 
-/*
- * IRQ handler for the RTC
- */
-static irqreturn_t at91_rtc_interrupt(int irq, void *_rtc)
+static irqreturn_t at91_rtc_cache_events(struct sam9_rtc *rtc)
 {
-        struct sam9_rtc *rtc = _rtc;
         u32 sr, mr;
-        unsigned long events = 0;
 
         /* Shared interrupt may be for another device.  Note: reading
          * SR clears it, so we must only read it in this irq handler!
@@ -290,18 +289,54 @@ static irqreturn_t at91_rtc_interrupt(int irq, void *_rtc)
 
         /* alarm status */
         if (sr & AT91_RTT_ALMS)
-                events |= (RTC_AF | RTC_IRQF);
+                rtc->events |= (RTC_AF | RTC_IRQF);
 
         /* timer update/increment */
         if (sr & AT91_RTT_RTTINC)
-                events |= (RTC_UF | RTC_IRQF);
+                rtc->events |= (RTC_UF | RTC_IRQF);
+
+        return IRQ_HANDLED;
+}
+
+static void at91_rtc_flush_events(struct sam9_rtc *rtc)
+{
+        if (!rtc->events)
+                return;
 
-        rtc_update_irq(rtc->rtcdev, 1, events);
+        rtc_update_irq(rtc->rtcdev, 1, rtc->events);
+        rtc->events = 0;
 
         pr_debug("%s: num=%ld, events=0x%02lx\n", __func__,
-                events >> 8, events & 0x000000FF);
+                rtc->events >> 8, rtc->events & 0x000000FF);
+}
 
-        return IRQ_HANDLED;
+/*
+ * IRQ handler for the RTC
+ */
+static irqreturn_t at91_rtc_interrupt(int irq, void *_rtc)
+{
+        struct sam9_rtc *rtc = _rtc;
+        int ret;
+
+        spin_lock(&rtc->lock);
+
+        ret = at91_rtc_cache_events(rtc);
+
+        /* We're called in suspended state */
+        if (rtc->suspended) {
+                /* Mask irqs coming from this peripheral */
+                rtt_writel(rtc, MR,
+                           rtt_readl(rtc, MR) &
+                           ~(AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN));
+                /* Trigger a system wakeup */
+                pm_system_wakeup();
+        } else {
+                at91_rtc_flush_events(rtc);
+        }
+
+        spin_unlock(&rtc->lock);
+
+        return ret;
 }
 
 static const struct rtc_class_ops at91_rtc_ops = {
@@ -421,7 +456,8 @@ static int at91_rtc_probe(struct platform_device *pdev)
 
         /* register irq handler after we know what name we'll use */
         ret = devm_request_irq(&pdev->dev, rtc->irq, at91_rtc_interrupt,
-                                IRQF_SHARED, dev_name(&rtc->rtcdev->dev), rtc);
+                               IRQF_SHARED | IRQF_COND_SUSPEND,
+                               dev_name(&rtc->rtcdev->dev), rtc);
         if (ret) {
                 dev_dbg(&pdev->dev, "can't share IRQ %d?\n", rtc->irq);
                 return ret;
@@ -482,7 +518,12 @@ static int at91_rtc_suspend(struct device *dev)
         rtc->imr = mr & (AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN);
         if (rtc->imr) {
                 if (device_may_wakeup(dev) && (mr & AT91_RTT_ALMIEN)) {
+                        unsigned long flags;
+
                         enable_irq_wake(rtc->irq);
+                        spin_lock_irqsave(&rtc->lock, flags);
+                        rtc->suspended = true;
+                        spin_unlock_irqrestore(&rtc->lock, flags);
                         /* don't let RTTINC cause wakeups */
                         if (mr & AT91_RTT_RTTINCIEN)
                                 rtt_writel(rtc, MR, mr & ~AT91_RTT_RTTINCIEN);
@@ -499,10 +540,18 @@ static int at91_rtc_resume(struct device *dev)
         u32             mr;
 
         if (rtc->imr) {
+                unsigned long flags;
+
                 if (device_may_wakeup(dev))
                         disable_irq_wake(rtc->irq);
                 mr = rtt_readl(rtc, MR);
                 rtt_writel(rtc, MR, mr | rtc->imr);
+
+                spin_lock_irqsave(&rtc->lock, flags);
+                rtc->suspended = false;
+                at91_rtc_cache_events(rtc);
+                at91_rtc_flush_events(rtc);
+                spin_unlock_irqrestore(&rtc->lock, flags);
         }
 
         return 0;