iwlwifi: mvm: several fixes in scan

The firmware doesn't handle properly the fragmented scan.
Stop using it.
While at it change max_out_time and suspend_time units from
usec to TUs as expected by firmware API.

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

2 files changed, 16 insertions, 45 deletions

diff --git a/drivers/net/wireless/iwlwifi/mvm/fw-api-scan.h b/drivers/net/wireless/iwlwifi/mvm/fw-api-scan.h
index 9426905de6b2..d73a89ecd78a 100644
--- a/drivers/net/wireless/iwlwifi/mvm/fw-api-scan.h
+++ b/drivers/net/wireless/iwlwifi/mvm/fw-api-scan.h
@@ -183,9 +183,9 @@ enum iwl_scan_type {
  *      this number of packets were received (typically 1)
  * @passive2active: is auto switching from passive to active during scan allowed
  * @rxchain_sel_flags: RXON_RX_CHAIN_*
- * @max_out_time: in usecs, max out of serving channel time
+ * @max_out_time: in TUs, max out of serving channel time
  * @suspend_time: how long to pause scan when returning to service channel:
- *      bits 0-19: beacon interal in usecs (suspend before executing)
+ *      bits 0-19: beacon interal in TUs (suspend before executing)
  *      bits 20-23: reserved
  *      bits 24-31: number of beacons (suspend between channels)
  * @rxon_flags: RXON_FLG_*
@@ -383,8 +383,8 @@ enum scan_framework_client {
  * @quiet_plcp_th:      quiet channel num of packets threshold
  * @good_CRC_th:        passive to active promotion threshold
  * @rx_chain:           RXON rx chain.
- * @max_out_time:       max uSec to be out of assoceated channel
- * @suspend_time:       pause scan this long when returning to service channel
+ * @max_out_time:       max TUs to be out of assoceated channel
+ * @suspend_time:       pause scan this TUs when returning to service channel
  * @flags:              RXON flags
  * @filter_flags:       RXONfilter
  * @tx_cmd:             tx command for active scan; for 2GHz and for 5GHz.
diff --git a/drivers/net/wireless/iwlwifi/mvm/scan.c b/drivers/net/wireless/iwlwifi/mvm/scan.c
index c91dc8498852..cba88a379fc8 100644
--- a/drivers/net/wireless/iwlwifi/mvm/scan.c
+++ b/drivers/net/wireless/iwlwifi/mvm/scan.c
@@ -277,51 +277,22 @@ static void iwl_mvm_scan_calc_params(struct iwl_mvm *mvm,
                                             IEEE80211_IFACE_ITER_NORMAL,
                                             iwl_mvm_scan_condition_iterator,
                                             &global_bound);
-        /*
-         * Under low latency traffic passive scan is fragmented meaning
-         * 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).
-         */
-        if (global_bound) {
-                if (!iwl_mvm_low_latency(mvm)) {
-                        params->suspend_time = ieee80211_tu_to_usec(100);
-                        params->max_out_time = ieee80211_tu_to_usec(600);
-                } else {
-                        params->suspend_time = ieee80211_tu_to_usec(105);
-                        /* P2P doesn't support fragmented passive scan, so
-                         * configure max_out_time to be at least longest dwell
-                         * time for passive scan.
-                         */
-                        if (vif->type == NL80211_IFTYPE_STATION && !vif->p2p) {
-                                params->max_out_time = ieee80211_tu_to_usec(70);
-                                params->passive_fragmented = true;
-                        } else {
-                                u32 passive_dwell;
 
-                                /*
-                                 * Use band G so that passive channel dwell time
-                                 * will be assigned with maximum value.
-                                 */
-                                band = IEEE80211_BAND_2GHZ;
-                                passive_dwell = iwl_mvm_get_passive_dwell(band);
-                                params->max_out_time =
-                                        ieee80211_tu_to_usec(passive_dwell);
-                        }
-                }
+        if (!global_bound)
+                goto not_bound;
+
+        params->suspend_time = 100;
+        params->max_out_time = 600;
+
+        if (iwl_mvm_low_latency(mvm)) {
+                params->suspend_time = 250;
+                params->max_out_time = 250;
         }
 
+not_bound:
+
         for (band = IEEE80211_BAND_2GHZ; band < IEEE80211_NUM_BANDS; band++) {
-                if (params->passive_fragmented)
-                        params->dwell[band].passive = 20;
-                else
-                        params->dwell[band].passive =
-                                iwl_mvm_get_passive_dwell(band);
+                params->dwell[band].passive = iwl_mvm_get_passive_dwell(band);
                 params->dwell[band].active = iwl_mvm_get_active_dwell(band,
                                                                       n_ssids);
         }