From f1e3d7d428616c04ef71bee3c2b6f274b8947755 Mon Sep 17 00:00:00 2001 From: Shanyu Zhao Date: Fri, 6 Nov 2009 14:52:47 -0800 Subject: [PATCH] iwlwifi: use only one chain for scan in PS When doing scan in power saving mode, choose only 1 valid RX chain instead of turning all chains on. Signed-off-by: Shanyu Zhao Signed-off-by: Wey-Yi Guy Signed-off-by: Reinette Chatre Signed-off-by: John W. Linville --- drivers/net/wireless/iwlwifi/iwl-scan.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-scan.c b/drivers/net/wireless/iwlwifi/iwl-scan.c index 1eb0d0bf1fe4..48bc2636a8ef 100644 --- a/drivers/net/wireless/iwlwifi/iwl-scan.c +++ b/drivers/net/wireless/iwlwifi/iwl-scan.c @@ -581,6 +581,7 @@ static void iwl_bg_request_scan(struct work_struct *data) u8 rate; bool is_active = false; int chan_mod; + u8 active_chains; conf = ieee80211_get_hw_conf(priv->hw); @@ -734,9 +735,22 @@ static void iwl_bg_request_scan(struct work_struct *data) rate_flags |= iwl_ant_idx_to_flags(priv->scan_tx_ant[band]); scan->tx_cmd.rate_n_flags = iwl_hw_set_rate_n_flags(rate, rate_flags); + /* In power save mode use one chain, otherwise use all chains */ + if (test_bit(STATUS_POWER_PMI, &priv->status)) { + /* rx_ant has been set to all valid chains previously */ + active_chains = rx_ant & + ((u8)(priv->chain_noise_data.active_chains)); + if (!active_chains) + active_chains = rx_ant; + + IWL_DEBUG_SCAN(priv, "chain_noise_data.active_chains: %u\n", + priv->chain_noise_data.active_chains); + + rx_ant = first_antenna(active_chains); + } /* MIMO is not used here, but value is required */ rx_chain |= ANT_ABC << RXON_RX_CHAIN_VALID_POS; - rx_chain |= ANT_ABC << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS; + rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_MIMO_SEL_POS; rx_chain |= rx_ant << RXON_RX_CHAIN_FORCE_SEL_POS; rx_chain |= 0x1 << RXON_RX_CHAIN_DRIVER_FORCE_POS; scan->rx_chain = cpu_to_le16(rx_chain); -- 2.39.2