iwlwifi: mvm: configure low latency dependent scan parameters

In case of system low latency configure passive scan to be fragmented.
Set the following scan parameters for both immediate and scheduled scan:
 - passive scan fragment duration = 20ms
 - out-of-channel time = 70ms
 - suspend time = 105ms
Restructure channel's active/passive dwell time configuration to better
suit the above change.

The idea is that under low latency traffic passive scan is fragmented,
i.e. that dwell on a particular channel will be fragmented. Each
fragment dwell time is 20ms and fragments period is 105ms. Skipping to
next channel will be delayed by the same period (105ms). So suspend_time
parameter describing both fragments and channels skipping periods is set
to 105ms. This value is chosen so that overall passive scan duration
will not be too long. Max_out_time in this case is set to 70ms, so for
active scanning operating channel will be left for 70ms while for
passive still for 20ms (fragment dwell).

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h
index d58118241d61..abfa5676762b 100644
--- a/drivers/net/wireless/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h
@@ -984,6 +984,8 @@ void iwl_mvm_update_smps(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 /* Low latency */
 int iwl_mvm_update_low_latency(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 			       bool value);
+/* get SystemLowLatencyMode - only needed for beacon threshold? */
+bool iwl_mvm_low_latency(struct iwl_mvm *mvm);
 /* get VMACLowLatencyMode */
 static inline bool iwl_mvm_vif_low_latency(struct iwl_mvm_vif *mvmvif)
 {