iwlwifi: always check if got h/w access before write

Before we write to the device registers always check if
iwl_grap_nic_access() was successful.

On the way change return type of grab_nic_access() to bool, and add
likely()/unlikely() statement.

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

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 5f390f8d3b8b..ce9ebeb89e4c 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -327,7 +327,7 @@ static void iwl_print_cont_event_trace(struct iwl_priv *priv, u32 base,
 
         /* Make sure device is powered up for SRAM reads */
         spin_lock_irqsave(&trans(priv)->reg_lock, reg_flags);
-        if (iwl_grab_nic_access(trans(priv))) {
+        if (unlikely(!iwl_grab_nic_access(trans(priv)))) {
                 spin_unlock_irqrestore(&trans(priv)->reg_lock, reg_flags);
                 return;
         }