iwlagn: reduce off channel reception for 4965

Force use of chains B and C (0x6) for Rx for 4965
Avoid A (0x1) because of its off-channel reception on A-band.

Signed-off-by: Rick Farrington <rickdic@hotmail.com>
Signed-off-by: Ben Cahill <ben.m.cahill@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index c72a99a..61788a5 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -2698,6 +2698,9 @@ static int iwl_mac_config(struct ieee80211_hw *hw, u32 changed)
 
        iwl_set_rate(priv);
 
+       /* call to ensure that 4965 rx_chain is set properly in monitor mode */
+       iwl_set_rxon_chain(priv);
+
        if (memcmp(&priv->active_rxon,
                   &priv->staging_rxon, sizeof(priv->staging_rxon)))
                iwl_commit_rxon(priv);

diff --git a/drivers/net/wireless/iwlwifi/iwl-commands.h b/drivers/net/wireless/iwlwifi/iwl-commands.h
index 3ced5e5..7571110 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-commands.h
+++ b/drivers/net/wireless/iwlwifi/iwl-commands.h
@@ -563,6 +563,7 @@ enum {
 
 
 #define RXON_RX_CHAIN_DRIVER_FORCE_MSK         cpu_to_le16(0x1 << 0)
+#define RXON_RX_CHAIN_DRIVER_FORCE_POS         (0)
 #define RXON_RX_CHAIN_VALID_MSK                        cpu_to_le16(0x7 << 1)
 #define RXON_RX_CHAIN_VALID_POS                        (1)
 #define RXON_RX_CHAIN_FORCE_SEL_MSK            cpu_to_le16(0x7 << 4)

diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index ef4a7c5..b64377e 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -753,6 +753,19 @@ void iwl_set_rxon_chain(struct iwl_priv *priv)
        rx_chain |= active_rx_cnt << RXON_RX_CHAIN_MIMO_CNT_POS;
        rx_chain |= idle_rx_cnt  << RXON_RX_CHAIN_CNT_POS;
 
+       /* copied from 'iwl_bg_request_scan()' */
+       /* Force use of chains B and C (0x6) for Rx for 4965
+        * Avoid A (0x1) because of its off-channel reception on A-band.
+        * MIMO is not used here, but value is required */
+       if (iwl_is_monitor_mode(priv) &&
+           !(priv->staging_rxon.flags & RXON_FLG_BAND_24G_MSK) &&
+           ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) == CSR_HW_REV_TYPE_4965)) {
+               rx_chain = 0x07 << RXON_RX_CHAIN_VALID_POS;
+               rx_chain |= 0x06 << RXON_RX_CHAIN_FORCE_SEL_POS;
+               rx_chain |= 0x07 << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS;
+               rx_chain |= 0x01 << RXON_RX_CHAIN_DRIVER_FORCE_POS;
+       }
+
        priv->staging_rxon.rx_chain = cpu_to_le16(rx_chain);
 
        if (!is_single && (active_rx_cnt >= IWL_NUM_RX_CHAINS_SINGLE) && is_cam)