1 files changed, 22 insertions, 4 deletions

diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 925006d3310..cb2f0728fd7 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -209,9 +209,8 @@ int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled)
         }
 
         if (err)
-                return err;
-
-        if (!rtc->ops)
+                /* nothing */;
+        else if (!rtc->ops)
                 err = -ENODEV;
         else if (!rtc->ops->alarm_irq_enable)
                 err = -EINVAL;
@@ -229,6 +228,12 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
         if (err)
                 return err;
 
+#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
+        if (enabled == 0 && rtc->uie_irq_active) {
+                mutex_unlock(&rtc->ops_lock);
+                return rtc_dev_update_irq_enable_emul(rtc, 0);
+        }
+#endif
         /* make sure we're changing state */
         if (rtc->uie_rtctimer.enabled == enabled)
                 goto out;
@@ -248,6 +253,16 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
 
 out:
         mutex_unlock(&rtc->ops_lock);
+#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
+        /*
+         * Enable emulation if the driver did not provide
+         * the update_irq_enable function pointer or if returned
+         * -EINVAL to signal that it has been configured without
+         * interrupts or that are not available at the moment.
+         */
+        if (err == -EINVAL)
+                err = rtc_dev_update_irq_enable_emul(rtc, enabled);
+#endif
         return err;
 
 }
@@ -263,7 +278,7 @@ EXPORT_SYMBOL_GPL(rtc_update_irq_enable);
  *
  * Triggers the registered irq_task function callback.
  */
-static void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode)
+void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode)
 {
         unsigned long flags;
 
@@ -464,6 +479,9 @@ int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq)
         int err = 0;
         unsigned long flags;
 
+        if (freq <= 0)
+                return -EINVAL;
+
         spin_lock_irqsave(&rtc->irq_task_lock, flags);
         if (rtc->irq_task != NULL && task == NULL)
                 err = -EBUSY;