1 files changed, 17 insertions, 7 deletions

diff --git a/drivers/net/wireless/ipw2x00/libipw_wx.c b/drivers/net/wireless/ipw2x00/libipw_wx.c
index dfbadb3b9bd5..3c0812db030a 100644
--- a/drivers/net/wireless/ipw2x00/libipw_wx.c
+++ b/drivers/net/wireless/ipw2x00/libipw_wx.c
@@ -43,6 +43,16 @@ static const char *ieee80211_modes[] = {
         "?", "a", "b", "ab", "g", "ag", "bg", "abg"
 };
 
+static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
+{
+        unsigned long end = jiffies;
+
+        if (end >= start)
+                return jiffies_to_msecs(end - start);
+
+        return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
+}
+
 #define MAX_CUSTOM_LEN 64
 static char *ieee80211_translate_scan(struct ieee80211_device *ieee,
                                       char *start, char *stop,
@@ -216,8 +226,8 @@ static char *ieee80211_translate_scan(struct ieee80211_device *ieee,
         iwe.cmd = IWEVCUSTOM;
         p = custom;
         p += snprintf(p, MAX_CUSTOM_LEN - (p - custom),
-                      " Last beacon: %dms ago",
-                      jiffies_to_msecs(jiffies - network->last_scanned));
+                      " Last beacon: %ums ago",
+                      elapsed_jiffies_msecs(network->last_scanned));
         iwe.u.data.length = p - custom;
         if (iwe.u.data.length)
                 start = iwe_stream_add_point(info, start, stop, &iwe, custom);
@@ -277,15 +287,15 @@ int ieee80211_wx_get_scan(struct ieee80211_device *ieee,
                     time_after(network->last_scanned + ieee->scan_age, jiffies))
                         ev = ieee80211_translate_scan(ieee, ev, stop, network,
                                                       info);
-                else
+                else {
                         IEEE80211_DEBUG_SCAN("Not showing network '%s ("
-                                             "%pM)' due to age (%dms).\n",
+                                             "%pM)' due to age (%ums).\n",
                                              print_ssid(ssid, network->ssid,
                                                          network->ssid_len),
                                              network->bssid,
-                                             jiffies_to_msecs(jiffies -
-                                                              network->
-                                                              last_scanned));
+                                             elapsed_jiffies_msecs(
+                                                       network->last_scanned));
+                }
         }
 
         spin_unlock_irqrestore(&ieee->lock, flags);