iwlwifi: mvm: don't send identical PHY_CTXT_CMD
When we have an AP which supports HT and a single HT
station is connected, we change the min_width from
NL80211_CHAN_WIDTH_20_NOHT to NL80211_CHAN_WIDTH_20. This
of course has no implication on the channel width but still
sends a command to the firmware.
Remember the last width that was sent and refrain from
sending unnecessary commands to the firmware.
Sending a PHY_CTXT_CMD to the firmware has a cost since it
recalculates the presence on the medium and because of that
it closes the transmit queues for a short while.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index d753047..d618046 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -3406,10 +3406,24 @@ static void iwl_mvm_change_chanctx(struct ieee80211_hw *hw,
return;
mutex_lock(&mvm->mutex);
+
+ /* we are only changing the min_width, may be a noop */
+ if (changed == IEEE80211_CHANCTX_CHANGE_MIN_WIDTH) {
+ if (phy_ctxt->width == ctx->min_def.width)
+ goto out_unlock;
+
+ /* we are just toggling between 20_NOHT and 20 */
+ if (phy_ctxt->width <= NL80211_CHAN_WIDTH_20 &&
+ ctx->min_def.width <= NL80211_CHAN_WIDTH_20)
+ goto out_unlock;
+ }
+
iwl_mvm_bt_coex_vif_change(mvm);
iwl_mvm_phy_ctxt_changed(mvm, phy_ctxt, &ctx->min_def,
ctx->rx_chains_static,
ctx->rx_chains_dynamic);
+
+out_unlock:
mutex_unlock(&mvm->mutex);
}