iwiwifi: mvm: Fix FW scan concurrency support assumptions

- The FW supports up to 4 concurrent scans, so adjust the definitions
  accordingly.
- Only a single periodic scan is supported, so enforce it in the code.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/fw/api/scan.h

@@ -8,7 +8,7 @@
  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
  * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018        Intel Corporation
+ * Copyright(c) 2018 - 2019 Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -31,7 +31,7 @@
  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
  * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018        Intel Corporation
+ * Copyright(c) 2018 - 2019 Intel Corporation
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -434,7 +434,7 @@ struct iwl_periodic_scan_complete {
 /* The maximum of either of these cannot exceed 8, because we use an
  * 8-bit mask (see IWL_MVM_SCAN_MASK in mvm.h).
  */
-#define IWL_MVM_MAX_UMAC_SCANS 8
+#define IWL_MVM_MAX_UMAC_SCANS 4
 #define IWL_MVM_MAX_LMAC_SCANS 1
 
 enum scan_config_flags {

drivers/net/wireless/intel/iwlwifi/mvm/scan.c

@@ -8,7 +8,7 @@
  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
  * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018 Intel Corporation
+ * Copyright(c) 2018 - 2019 Intel Corporation
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -31,7 +31,7 @@
  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
  * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
- * Copyright(c) 2018 Intel Corporation
+ * Copyright(c) 2018 - 2019 Intel Corporation
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -1580,6 +1580,11 @@ static int iwl_mvm_check_running_scans(struct iwl_mvm *mvm, int type)
 	 * scheduled scan before starting a normal scan.
 	 */
 
+	/* FW supports only a single periodic scan */
+	if ((type == IWL_MVM_SCAN_SCHED || type == IWL_MVM_SCAN_NETDETECT) &&
+	    mvm->scan_status & (IWL_MVM_SCAN_SCHED | IWL_MVM_SCAN_NETDETECT))
+		return -EBUSY;
+
 	if (iwl_mvm_num_scans(mvm) < mvm->max_scans)
 		return 0;