iwlwifi: kill elapsed_jiffies

Subtract of jiffies is fine even if one variable overwrap.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-helpers.h

@@ -44,15 +44,6 @@ static inline struct ieee80211_conf *ieee80211_get_hw_conf(
 	return &hw->conf;
 }
 
-static inline unsigned long elapsed_jiffies(unsigned long start,
-					    unsigned long end)
-{
-	if (end >= start)
-		return end - start;
-
-	return end + (MAX_JIFFY_OFFSET - start) + 1;
-}
-
 /**
  * iwl_queue_inc_wrap - increment queue index, wrap back to beginning
  * @index -- current index

drivers/net/wireless/iwlwifi/iwl-scan.c

@@ -252,8 +252,7 @@ static void iwl_rx_scan_complete_notif(struct iwl_priv *priv,
 
 	IWL_DEBUG_SCAN(priv, "Scan on %sGHz took %dms\n",
 		       (priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2",
-		       jiffies_to_msecs(elapsed_jiffies
-					(priv->scan_start, jiffies)));
+		       jiffies_to_msecs(jiffies - priv->scan_start));
 
 	queue_work(priv->workqueue, &priv->scan_completed);