iwlwifi: correct math in elapsed_jiffies

w/o the first change: if end == start you get MAX_JIFFY_OFFSET which
isn't what you want...

For the latter I think to be technically correct you need the +1 to
account for the jiffy between MAX_JIFFY_OFFSET and 0

(hmm w/ the 2nd change the first isn't strictly needed... ah well)

Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-helpers.h b/drivers/net/wireless/iwlwifi/iwl-helpers.h
index cd2eb184831..cb009f4c401 100644
--- a/drivers/net/wireless/iwlwifi/iwl-helpers.h
+++ b/drivers/net/wireless/iwlwifi/iwl-helpers.h
@@ -246,10 +246,10 @@ static inline int iwl_check_bits(unsigned long field, unsigned long mask)
 static inline unsigned long elapsed_jiffies(unsigned long start,
                                             unsigned long end)
 {
-        if (end > start)
+        if (end >= start)
                 return end - start;
 
-        return end + (MAX_JIFFY_OFFSET - start);
+        return end + (MAX_JIFFY_OFFSET - start) + 1;
 }
 
 static inline u8 iwl_get_dma_hi_address(dma_addr_t addr)