iwlwifi: mvm: add extended dwell time

When doing active scan on crowded channels we are likely to miss probe
responses due to collisions. To overcome this issue we use an extended
dwell time on channels 1, 6 and 11; this dwell time is set to 100.

In case of fragmented scan extended dwell time is the maximum out of
channel time - 44 msec. Fragmented active scan will be addressed later.

Extended dwell time isn't used in sched scan or p2p find.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 31 insertions, 10 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/scan.c b/drivers/net/wireless/intel/iwlwifi/mvm/scan.c
index 87cc993f044a..bee3201c7116 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/scan.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/scan.c
@@ -82,6 +82,7 @@ struct iwl_mvm_scan_timing_params {
         u32 dwell_active;
         u32 dwell_passive;
         u32 dwell_fragmented;
+        u32 dwell_extended;
         u32 suspend_time;
         u32 max_out_time;
 };
@@ -91,6 +92,7 @@ static struct iwl_mvm_scan_timing_params scan_timing[] = {
                 .dwell_active = 10,
                 .dwell_passive = 110,
                 .dwell_fragmented = 44,
+                .dwell_extended = 100,
                 .suspend_time = 0,
                 .max_out_time = 0,
         },
@@ -98,6 +100,7 @@ static struct iwl_mvm_scan_timing_params scan_timing[] = {
                 .dwell_active = 10,
                 .dwell_passive = 110,
                 .dwell_fragmented = 44,
+                .dwell_extended = 100,
                 .suspend_time = 30,
                 .max_out_time = 120,
         },
@@ -105,6 +108,7 @@ static struct iwl_mvm_scan_timing_params scan_timing[] = {
                 .dwell_active = 10,
                 .dwell_passive = 110,
                 .dwell_fragmented = 44,
+                .dwell_extended = 100,
                 .suspend_time = 120,
                 .max_out_time = 120,
         },
@@ -112,6 +116,7 @@ static struct iwl_mvm_scan_timing_params scan_timing[] = {
                 .dwell_active = 10,
                 .dwell_passive = 110,
                 .dwell_fragmented = 44,
+                .dwell_extended = 44,
                 .suspend_time = 95,
                 .max_out_time = 44,
         },
@@ -716,6 +721,7 @@ static void iwl_mvm_scan_lmac_dwell(struct iwl_mvm *mvm,
         cmd->active_dwell = scan_timing[params->type].dwell_active;
         cmd->passive_dwell = scan_timing[params->type].dwell_passive;
         cmd->fragmented_dwell = scan_timing[params->type].dwell_fragmented;
+        cmd->extended_dwell = scan_timing[params->type].dwell_extended;
         cmd->max_out_time = cpu_to_le32(scan_timing[params->type].max_out_time);
         cmd->suspend_time = cpu_to_le32(scan_timing[params->type].suspend_time);
         cmd->scan_prio = iwl_mvm_scan_priority(mvm, IWL_SCAN_PRIORITY_EXT_6);
@@ -749,8 +755,15 @@ static inline bool iwl_mvm_scan_use_ebs(struct iwl_mvm *mvm,
                 vif->type != NL80211_IFTYPE_P2P_DEVICE);
 }
 
+static inline bool iwl_mvm_is_regular_scan(struct iwl_mvm_scan_params *params)
+{
+        return params->n_scan_plans == 1 &&
+                params->scan_plans[0].iterations == 1;
+}
+
 static int iwl_mvm_scan_lmac_flags(struct iwl_mvm *mvm,
-                                   struct iwl_mvm_scan_params *params)
+                                   struct iwl_mvm_scan_params *params,
+                                   struct ieee80211_vif *vif)
 {
         int flags = 0;
 
@@ -776,6 +789,10 @@ static int iwl_mvm_scan_lmac_flags(struct iwl_mvm *mvm,
                 flags |= IWL_MVM_LMAC_SCAN_FLAG_ITER_COMPLETE;
 #endif
 
+        if (iwl_mvm_is_regular_scan(params) &&
+            vif->type != NL80211_IFTYPE_P2P_DEVICE)
+                flags |= IWL_MVM_LMAC_SCAN_FLAG_EXTENDED_DWELL;
+
         return flags;
 }
 
@@ -804,7 +821,8 @@ static int iwl_mvm_scan_lmac(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 
         cmd->delay = cpu_to_le32(params->delay);
 
-        cmd->scan_flags = cpu_to_le32(iwl_mvm_scan_lmac_flags(mvm, params));
+        cmd->scan_flags = cpu_to_le32(iwl_mvm_scan_lmac_flags(mvm, params,
+                                                              vif));
 
         cmd->flags = iwl_mvm_scan_rxon_flags(params->channels[0]->band);
         cmd->filter_flags = cpu_to_le32(MAC_FILTER_ACCEPT_GRP |
@@ -942,6 +960,7 @@ int iwl_mvm_config_scan(struct iwl_mvm *mvm)
         scan_config->dwell_active = scan_timing[type].dwell_active;
         scan_config->dwell_passive = scan_timing[type].dwell_passive;
         scan_config->dwell_fragmented = scan_timing[type].dwell_fragmented;
+        scan_config->dwell_extended = scan_timing[type].dwell_extended;
 
         memcpy(&scan_config->mac_addr, &mvm->addresses[0].addr, ETH_ALEN);
 
@@ -983,16 +1002,11 @@ static int iwl_mvm_scan_uid_by_status(struct iwl_mvm *mvm, int status)
         return -ENOENT;
 }
 
-static inline bool iwl_mvm_is_regular_scan(struct iwl_mvm_scan_params *params)
-{
-        return params->n_scan_plans == 1 &&
-                params->scan_plans[0].iterations == 1;
-}
-
 static void iwl_mvm_scan_umac_dwell(struct iwl_mvm *mvm,
                                     struct iwl_scan_req_umac *cmd,
                                     struct iwl_mvm_scan_params *params)
 {
+        cmd->extended_dwell = scan_timing[params->type].dwell_extended;
         cmd->active_dwell = scan_timing[params->type].dwell_active;
         cmd->passive_dwell = scan_timing[params->type].dwell_passive;
         cmd->fragmented_dwell = scan_timing[params->type].dwell_fragmented;
@@ -1027,7 +1041,8 @@ iwl_mvm_umac_scan_cfg_channels(struct iwl_mvm *mvm,
 }
 
 static u32 iwl_mvm_scan_umac_flags(struct iwl_mvm *mvm,
-                                   struct iwl_mvm_scan_params *params)
+                                   struct iwl_mvm_scan_params *params,
+                                   struct ieee80211_vif *vif)
 {
         int flags = 0;
 
@@ -1055,6 +1070,11 @@ static u32 iwl_mvm_scan_umac_flags(struct iwl_mvm *mvm,
         if (mvm->scan_iter_notif_enabled)
                 flags |= IWL_UMAC_SCAN_GEN_FLAGS_ITER_COMPLETE;
 #endif
+
+        if (iwl_mvm_is_regular_scan(params) &&
+            vif->type != NL80211_IFTYPE_P2P_DEVICE)
+                flags |= IWL_UMAC_SCAN_GEN_FLAGS_EXTENDED_DWELL;
+
         return flags;
 }
 
@@ -1085,7 +1105,8 @@ static int iwl_mvm_scan_umac(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
         mvm->scan_uid_status[uid] = type;
 
         cmd->uid = cpu_to_le32(uid);
-        cmd->general_flags = cpu_to_le32(iwl_mvm_scan_umac_flags(mvm, params));
+        cmd->general_flags = cpu_to_le32(iwl_mvm_scan_umac_flags(mvm, params,
+                                                                 vif));
 
         if (type == IWL_MVM_SCAN_SCHED)
                 cmd->flags = cpu_to_le32(IWL_UMAC_SCAN_FLAG_PREEMPTIVE);