iwlwifi: mvm: fix netdetect starting/stopping for unified images

With unified images, we need to make sure the net-detect scan is
stopped after resuming, since we don't restart the FW.  Also, we need
to make sure we check if there are enough scan slots available to run
it, as we do with other scans.

Fixes: commit 23ae61282b88 ("iwlwifi: mvm: Do not switch to D3 image on suspend")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
index 03a8fc5..b88e204 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/d3.c
@@ -1087,6 +1087,15 @@
 		ret = iwl_mvm_switch_to_d3(mvm);
 		if (ret)
 			return ret;
+	} else {
+		/* In theory, we wouldn't have to stop a running sched
+		 * scan in order to start another one (for
+		 * net-detect).  But in practice this doesn't seem to
+		 * work properly, so stop any running sched_scan now.
+		 */
+		ret = iwl_mvm_scan_stop(mvm, IWL_MVM_SCAN_SCHED, true);
+		if (ret)
+			return ret;
 	}
 
 	/* rfkill release can be either for wowlan or netdetect */
@@ -2091,6 +2100,16 @@
 	iwl_mvm_update_changed_regdom(mvm);
 
 	if (mvm->net_detect) {
+		/* If this is a non-unified image, we restart the FW,
+		 * so no need to stop the netdetect scan.  If that
+		 * fails, continue and try to get the wake-up reasons,
+		 * but trigger a HW restart by keeping a failure code
+		 * in ret.
+		 */
+		if (unified_image)
+			ret = iwl_mvm_scan_stop(mvm, IWL_MVM_SCAN_NETDETECT,
+						false);
+
 		iwl_mvm_query_netdetect_reasons(mvm, vif);
 		/* has unlocked the mutex, so skip that */
 		goto out;