3 files changed, 14 insertions, 4 deletions

diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index 37b1d82fda08..f8a0aab218cb 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -31,8 +31,12 @@ static void rtc_device_release(struct device *dev)
         kfree(rtc);
 }
 
-#if defined(CONFIG_PM) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
+#ifdef CONFIG_RTC_HCTOSYS_DEVICE
+/* Result of the last RTC to system clock attempt. */
+int rtc_hctosys_ret = -ENODEV;
+#endif
 
+#if defined(CONFIG_PM) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
 /*
  * On suspend(), measure the delta between one RTC and the
  * system's wall clock; restore it on resume().
@@ -84,6 +88,7 @@ static int rtc_resume(struct device *dev)
         struct timespec         new_system, new_rtc;
         struct timespec         sleep_time;
 
+        rtc_hctosys_ret = -ENODEV;
         if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)
                 return 0;
 
@@ -117,6 +122,7 @@ static int rtc_resume(struct device *dev)
 
         if (sleep_time.tv_sec >= 0)
                 timekeeping_inject_sleeptime(&sleep_time);
+        rtc_hctosys_ret = 0;
         return 0;
 }
 
diff --git a/drivers/rtc/hctosys.c b/drivers/rtc/hctosys.c
index bc90b091f195..4aa60d74004e 100644
--- a/drivers/rtc/hctosys.c
+++ b/drivers/rtc/hctosys.c
@@ -22,8 +22,6 @@
  * the best guess is to add 0.5s.
  */
 
-int rtc_hctosys_ret = -ENODEV;
-
 static int __init rtc_hctosys(void)
 {
         int err = -ENODEV;
@@ -56,7 +54,7 @@ static int __init rtc_hctosys(void)
 
         rtc_tm_to_time(&tm, &tv.tv_sec);
 
-        do_settimeofday(&tv);
+        err = do_settimeofday(&tv);
 
         dev_info(rtc->dev.parent,
                 "setting system clock to "
diff --git a/drivers/rtc/rtc-sysfs.c b/drivers/rtc/rtc-sysfs.c
index 380083ca572f..b70e2bb63645 100644
--- a/drivers/rtc/rtc-sysfs.c
+++ b/drivers/rtc/rtc-sysfs.c
@@ -102,6 +102,12 @@ rtc_sysfs_set_max_user_freq(struct device *dev, struct device_attribute *attr,
         return n;
 }
 
+/**
+ * rtc_sysfs_show_hctosys - indicate if the given RTC set the system time
+ *
+ * Returns 1 if the system clock was set by this RTC at the last
+ * boot or resume event.
+ */
 static ssize_t
 rtc_sysfs_show_hctosys(struct device *dev, struct device_attribute *attr,
                 char *buf)