iwlwifi: mvm: generalize the other-scan stopping code

[deliverable/linux.git] / drivers / net / wireless / iwlwifi / mvm / mac80211.c

diff --git a/drivers/net/wireless/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
index f57d584c288a2ca7b512934a5335faf56ccacc99..a5fe070cc4df2359c734bd8db76e3dcbdca5301a 100644 (file)
--- a/drivers/net/wireless/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac80211.c
@@ -510,6 +510,14 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
 
        hw->wiphy->max_scan_ssids = PROBE_OPTION_MAX;
 
+       BUILD_BUG_ON(IWL_MVM_MAX_UMAC_SCANS > HWEIGHT32(IWL_MVM_SCAN_MASK) ||
+                    IWL_MVM_MAX_LMAC_SCANS > HWEIGHT32(IWL_MVM_SCAN_MASK));
+
+       if (mvm->fw->ucode_capa.capa[0] & IWL_UCODE_TLV_CAPA_UMAC_SCAN)
+               mvm->max_scans = IWL_MVM_MAX_UMAC_SCANS;
+       else
+               mvm->max_scans = IWL_MVM_MAX_LMAC_SCANS;
+
        if (mvm->nvm_data->bands[IEEE80211_BAND_2GHZ].n_channels)
                hw->wiphy->bands[IEEE80211_BAND_2GHZ] =
                        &mvm->nvm_data->bands[IEEE80211_BAND_2GHZ];
@@ -1426,7 +1434,7 @@ void __iwl_mvm_mac_stop(struct iwl_mvm *mvm)
        if (mvm->fw->ucode_capa.capa[0] & IWL_UCODE_TLV_CAPA_UMAC_SCAN) {
                int i;
 
-               for (i = 0; i < IWL_MVM_MAX_SIMULTANEOUS_SCANS; i++) {
+               for (i = 0; i < mvm->max_scans; i++) {
                        if (WARN_ONCE(mvm->scan_uid[i],
                                      "UMAC scan UID %d was not cleaned\n",
                                      mvm->scan_uid[i]))
@@ -2373,6 +2381,46 @@ static void iwl_mvm_bss_info_changed(struct ieee80211_hw *hw,
        iwl_mvm_unref(mvm, IWL_MVM_REF_BSS_CHANGED);
 }
 
+static int iwl_mvm_num_scans(struct iwl_mvm *mvm)
+{
+       return hweight32(mvm->scan_status & IWL_MVM_SCAN_MASK);
+}
+
+static int iwl_mvm_check_running_scans(struct iwl_mvm *mvm, int type)
+{
+       /* This looks a bit arbitrary, but the idea is that if we run
+        * out of possible simultaneous scans and the userspace is
+        * trying to run a scan type that is already running, we
+        * return -EBUSY.  But if the userspace wants to start a
+        * different type of scan, we stop the opposite type to make
+        * space for the new request.  The reason is backwards
+        * compatibility with old wpa_supplicant that wouldn't stop a
+        * scheduled scan before starting a normal scan.
+        */
+
+       if (iwl_mvm_num_scans(mvm) < mvm->max_scans)
+               return 0;
+
+       /* Use a switch, even though this is a bitmask, so that more
+        * than one bits set will fall in default and we will warn.
+        */
+       switch (type) {
+       case IWL_MVM_SCAN_REGULAR:
+               if (mvm->scan_status & IWL_MVM_SCAN_REGULAR_MASK)
+                       return -EBUSY;
+               return iwl_mvm_scan_offload_stop(mvm, true);
+       case IWL_MVM_SCAN_SCHED:
+               if (mvm->scan_status & IWL_MVM_SCAN_SCHED_MASK)
+                       return -EBUSY;
+               return iwl_mvm_cancel_scan(mvm);
+       default:
+               WARN_ON(1);
+               break;
+       }
+
+       return -EIO;
+}
+
 static int iwl_mvm_mac_hw_scan(struct ieee80211_hw *hw,
                               struct ieee80211_vif *vif,
                               struct ieee80211_scan_request *hw_req)
@@ -2393,17 +2441,9 @@ static int iwl_mvm_mac_hw_scan(struct ieee80211_hw *hw,
                goto out;
        }
 
-       if (mvm->scan_status & IWL_MVM_SCAN_REGULAR) {
-               ret = -EBUSY;
+       ret = iwl_mvm_check_running_scans(mvm, IWL_MVM_SCAN_REGULAR);
+       if (ret)
                goto out;
-       }
-
-       if (!(mvm->fw->ucode_capa.capa[0] & IWL_UCODE_TLV_CAPA_UMAC_SCAN) &&
-           (mvm->scan_status & IWL_MVM_SCAN_SCHED)) {
-               ret = iwl_mvm_scan_offload_stop(mvm, true);
-               if (ret)
-                       goto out;
-       }
 
        iwl_mvm_ref(mvm, IWL_MVM_REF_SCAN);
 
@@ -2769,17 +2809,9 @@ static int iwl_mvm_mac_sched_scan_start(struct ieee80211_hw *hw,
                goto out;
        }
 
-       if (mvm->scan_status & IWL_MVM_SCAN_SCHED) {
-               ret = -EBUSY;
+       ret = iwl_mvm_check_running_scans(mvm, IWL_MVM_SCAN_SCHED);
+       if (ret)
                goto out;
-       }
-
-       if (!(mvm->fw->ucode_capa.capa[0] & IWL_UCODE_TLV_CAPA_UMAC_SCAN) &&
-           (mvm->scan_status & IWL_MVM_SCAN_REGULAR)) {
-               ret = iwl_mvm_cancel_scan(mvm);
-               if (ret)
-                       goto out;
-       }
 
        ret = iwl_mvm_scan_offload_start(mvm, vif, req, ies);
        if (ret)