iwlwifi: check control channel for pure 40MHz

for pure 40MHz mode, set the control channel location if provided, but not
like Mixed mode; if information is not provided, still allow 40MHz
operation.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index b2875fe12561..b122eedef369 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -826,9 +826,18 @@ void iwl_set_rxon_ht(struct iwl_priv *priv, struct iwl_ht_info *ht_info)
                          RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK);
         if (iwl_is_fat_tx_allowed(priv, NULL)) {
                 /* pure 40 fat */
-                if (ht_info->ht_protection == IEEE80211_HT_OP_MODE_PROTECTION_20MHZ)
+                if (ht_info->ht_protection == IEEE80211_HT_OP_MODE_PROTECTION_20MHZ) {
                         rxon->flags |= RXON_FLG_CHANNEL_MODE_PURE_40;
-                else {
+                        /* Note: control channel is opposite of extension channel */
+                        switch (ht_info->extension_chan_offset) {
+                        case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
+                                rxon->flags &= ~RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK;
+                                break;
+                        case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
+                                rxon->flags |= RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK;
+                                break;
+                        }
+                } else {
                         /* Note: control channel is opposite of extension channel */
                         switch (ht_info->extension_chan_offset) {
                         case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: