iwlwifi: move chain settings to agn
The core module doesn't need to carry around
the code for chain settings that is used for
HT drivers (agn) only.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-lib.c b/drivers/net/wireless/iwlwifi/iwl-agn-lib.c
index 3fa2c5c..0b45bce 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-lib.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-lib.c
@@ -2065,3 +2065,143 @@
{
cancel_work_sync(&priv->bt_traffic_change_work);
}
+
+static bool is_single_rx_stream(struct iwl_priv *priv)
+{
+ return priv->current_ht_config.smps == IEEE80211_SMPS_STATIC ||
+ priv->current_ht_config.single_chain_sufficient;
+}
+
+#define IWL_NUM_RX_CHAINS_MULTIPLE 3
+#define IWL_NUM_RX_CHAINS_SINGLE 2
+#define IWL_NUM_IDLE_CHAINS_DUAL 2
+#define IWL_NUM_IDLE_CHAINS_SINGLE 1
+
+/*
+ * Determine how many receiver/antenna chains to use.
+ *
+ * More provides better reception via diversity. Fewer saves power
+ * at the expense of throughput, but only when not in powersave to
+ * start with.
+ *
+ * MIMO (dual stream) requires at least 2, but works better with 3.
+ * This does not determine *which* chains to use, just how many.
+ */
+static int iwl_get_active_rx_chain_count(struct iwl_priv *priv)
+{
+ if (priv->cfg->bt_params &&
+ priv->cfg->bt_params->advanced_bt_coexist &&
+ (priv->bt_full_concurrent ||
+ priv->bt_traffic_load >= IWL_BT_COEX_TRAFFIC_LOAD_HIGH)) {
+ /*
+ * only use chain 'A' in bt high traffic load or
+ * full concurrency mode
+ */
+ return IWL_NUM_RX_CHAINS_SINGLE;
+ }
+ /* # of Rx chains to use when expecting MIMO. */
+ if (is_single_rx_stream(priv))
+ return IWL_NUM_RX_CHAINS_SINGLE;
+ else
+ return IWL_NUM_RX_CHAINS_MULTIPLE;
+}
+
+/*
+ * When we are in power saving mode, unless device support spatial
+ * multiplexing power save, use the active count for rx chain count.
+ */
+static int iwl_get_idle_rx_chain_count(struct iwl_priv *priv, int active_cnt)
+{
+ /* # Rx chains when idling, depending on SMPS mode */
+ switch (priv->current_ht_config.smps) {
+ case IEEE80211_SMPS_STATIC:
+ case IEEE80211_SMPS_DYNAMIC:
+ return IWL_NUM_IDLE_CHAINS_SINGLE;
+ case IEEE80211_SMPS_OFF:
+ return active_cnt;
+ default:
+ WARN(1, "invalid SMPS mode %d",
+ priv->current_ht_config.smps);
+ return active_cnt;
+ }
+}
+
+/* up to 4 chains */
+static u8 iwl_count_chain_bitmap(u32 chain_bitmap)
+{
+ u8 res;
+ res = (chain_bitmap & BIT(0)) >> 0;
+ res += (chain_bitmap & BIT(1)) >> 1;
+ res += (chain_bitmap & BIT(2)) >> 2;
+ res += (chain_bitmap & BIT(3)) >> 3;
+ return res;
+}
+
+/**
+ * iwlagn_set_rxon_chain - Set up Rx chain usage in "staging" RXON image
+ *
+ * Selects how many and which Rx receivers/antennas/chains to use.
+ * This should not be used for scan command ... it puts data in wrong place.
+ */
+void iwlagn_set_rxon_chain(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
+{
+ bool is_single = is_single_rx_stream(priv);
+ bool is_cam = !test_bit(STATUS_POWER_PMI, &priv->status);
+ u8 idle_rx_cnt, active_rx_cnt, valid_rx_cnt;
+ u32 active_chains;
+ u16 rx_chain;
+
+ /* Tell uCode which antennas are actually connected.
+ * Before first association, we assume all antennas are connected.
+ * Just after first association, iwl_chain_noise_calibration()
+ * checks which antennas actually *are* connected. */
+ if (priv->chain_noise_data.active_chains)
+ active_chains = priv->chain_noise_data.active_chains;
+ else
+ active_chains = priv->hw_params.valid_rx_ant;
+
+ if (priv->cfg->bt_params &&
+ priv->cfg->bt_params->advanced_bt_coexist &&
+ (priv->bt_full_concurrent ||
+ priv->bt_traffic_load >= IWL_BT_COEX_TRAFFIC_LOAD_HIGH)) {
+ /*
+ * only use chain 'A' in bt high traffic load or
+ * full concurrency mode
+ */
+ active_chains = first_antenna(active_chains);
+ }
+
+ rx_chain = active_chains << RXON_RX_CHAIN_VALID_POS;
+
+ /* How many receivers should we use? */
+ active_rx_cnt = iwl_get_active_rx_chain_count(priv);
+ idle_rx_cnt = iwl_get_idle_rx_chain_count(priv, active_rx_cnt);
+
+
+ /* correct rx chain count according hw settings
+ * and chain noise calibration
+ */
+ valid_rx_cnt = iwl_count_chain_bitmap(active_chains);
+ if (valid_rx_cnt < active_rx_cnt)
+ active_rx_cnt = valid_rx_cnt;
+
+ if (valid_rx_cnt < idle_rx_cnt)
+ idle_rx_cnt = valid_rx_cnt;
+
+ rx_chain |= active_rx_cnt << RXON_RX_CHAIN_MIMO_CNT_POS;
+ rx_chain |= idle_rx_cnt << RXON_RX_CHAIN_CNT_POS;
+
+ ctx->staging.rx_chain = cpu_to_le16(rx_chain);
+
+ if (!is_single && (active_rx_cnt >= IWL_NUM_RX_CHAINS_SINGLE) && is_cam)
+ ctx->staging.rx_chain |= RXON_RX_CHAIN_MIMO_FORCE_MSK;
+ else
+ ctx->staging.rx_chain &= ~RXON_RX_CHAIN_MIMO_FORCE_MSK;
+
+ IWL_DEBUG_ASSOC(priv, "rx_chain=0x%X active=%d idle=%d\n",
+ ctx->staging.rx_chain,
+ active_rx_cnt, idle_rx_cnt);
+
+ WARN_ON(active_rx_cnt == 0 || idle_rx_cnt == 0 ||
+ active_rx_cnt < idle_rx_cnt);
+}