ath11k: add handler for scan event WMI_SCAN_EVENT_DEQUEUED

From: Wen Gong <[email protected]>

When wlan interface is up, 11d scan is sent to the firmware, and the firmware needs to spend couple of seconds to complete the 11d scan. If immediately a normal scan from user space arrives to ath11k, then the normal scan request is also sent to the firmware, but the scan started event will be reported to ath11k until the 11d scan complete. When timed out for the scan started in ath11k, ath11k stops the normal scan and the firmware reports WMI_SCAN_EVENT_DEQUEUED to ath11k for the normal scan. ath11k has no handler for the event and then timed out for the scan completed in ath11k_scan_stop(), and ath11k prints the following error message.

[ 1491.604750] ath11k_pci 0000:02:00.0: failed to receive scan abort comple: timed out
[ 1491.604756] ath11k_pci 0000:02:00.0: failed to stop scan: -110
[ 1491.604758] ath11k_pci 0000:02:00.0: failed to start hw scan: -110

Add a handler for WMI_SCAN_EVENT_DEQUEUED and then complete the scan to get rid of the above error message.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1

---
 drivers/net/wireless/ath/ath11k/wmi.c | 2 ++
 1 file changed, 2 insertions(+)

index ec46e06aace9..d11022455d97 100644
@@ -6370,6 +6370,8 @@ static void ath11k_scan_event(struct ath11k_base *ab, struct sk_buff *skb)
 		ath11k_wmi_event_scan_start_failed(ar);
 		break;
 	case WMI_SCAN_EVENT_DEQUEUED:
+		__ath11k_mac_scan_finish(ar);
+		break;
 	case WMI_SCAN_EVENT_PREEMPTED:
 	case WMI_SCAN_EVENT_RESTARTED:
 	case WMI_SCAN_EVENT_FOREIGN_CHAN_EXIT:

2.25.1

From: Wen Gong <[email protected]>

ath11k prints "Received scan event for unknown vdev" when doing the following test:
1. trigger scan
2. wait 0.2 second
3. iw reg set or 11d scan complete from firmware

Reason: When iw reg set or 11d scan complete, the new country code will be set to the firmware, and the new regdomain info indicated to ath11k, then the new channel list will be sent to the firmware. The firmware will cancel the current scan after receiving WMI_SCAN_CHAN_LIST_CMDID which is used for the new channel list, and the state of ath11k is ATH11K_SCAN_RUNNING, then ath11k_get_ar_on_scan_abort() returns NULL and ath11k_scan_event() returns at this point and does not indicate scan completion to mac80211.

Indicate scan completion to mac80211 and get rid of the "Received scan event for unknown vdev" print for the above case.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1

---
 drivers/net/wireless/ath/ath11k/wmi.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

index d11022455d97..613362b28d8e 100644
@@ -6289,8 +6289,9 @@ static void ath11k_mgmt_tx_compl_event(struct ath11k_base *ab, struct sk_buff *s
 	rcu_read_unlock();
 }
 
-static struct ath11k *ath11k_get_ar_on_scan_abort(struct ath11k_base *ab,
-						  u32 vdev_id)
+static struct ath11k *ath11k_get_ar_on_scan_state(struct ath11k_base *ab,
+						  u32 vdev_id,
+						  enum ath11k_scan_state state)
 {
 	int i;
 	struct ath11k_pdev *pdev;

@@ -6302,7 +6303,7 @@ static struct ath11k *ath11k_get_ar_on_scan_abort(struct ath11k_base *ab,
 			ar = pdev->ar;
 
 			spin_lock_bh(&ar->data_lock);
-			if (ar->scan.state == ATH11K_SCAN_ABORTING &&
+			if (ar->scan.state == state &&
 			    ar->scan.vdev_id == vdev_id) {
 				spin_unlock_bh(&ar->data_lock);
 				return ar;

@@ -6332,10 +6333,15 @@ static void ath11k_scan_event(struct ath11k_base *ab, struct sk_buff *skb)
 	 * aborting scan's vdev id matches this event info.
 	 */
 	if (scan_ev.event_type == WMI_SCAN_EVENT_COMPLETED &&
-	    scan_ev.reason == WMI_SCAN_REASON_CANCELLED)
-		ar = ath11k_get_ar_on_scan_abort(ab, scan_ev.vdev_id);
-	else
+	    scan_ev.reason == WMI_SCAN_REASON_CANCELLED) {
+		ar = ath11k_get_ar_on_scan_state(ab, scan_ev.vdev_id,
+						 ATH11K_SCAN_ABORTING);
+		if (!ar)
+			ar = ath11k_get_ar_on_scan_state(ab, scan_ev.vdev_id,
+							 ATH11K_SCAN_RUNNING);
+	} else {
 		ar = ath11k_mac_get_ar_by_vdev_id(ab, scan_ev.vdev_id);
+	}
 
 	if (!ar) {
 		ath11k_warn(ab, "Received scan event for unknown vdev");

2.25.1

From: Wen Gong <[email protected]>

Scan failure can not be recovered from when running a loop of the following steps:
1. run scan: "iw wlan scan".
2. run command: echo assert > /sys/kernel/debug/ath11k/qca6490\ hw2.0/simulate_fw_crash immediately after step 1.

result:
scan failed and can not recover even when wlan recovery succeeds:
command failed: Device or resource busy (-16)

reason:
When scan arrives, WMI_START_SCAN_CMDID is sent to the firmware and function ath11k_mac_op_hw_scan() returns, then simulate_fw_crash arrives and the scan started event does not arrive, and then it starts to do recovery of wlan. __ath11k_mac_scan_finish() which is called from ath11k_core_halt() is one step of recovery, it will not call ieee80211_scan_completed() by logic currently because the scan state is ATH11K_SCAN_STARTING. Thus it leads the scan not being completed in mac80211, and leads all consecutive scans failing with -EBUSY in nl80211_trigger_scan even after wlan recovery success.

Indicate scan complete with aborted flag to mac80211 for ATH11K_SCAN_STARTING to allow recovery from scan failed with "Device or resource busy (-16)" after wlan recovery.

Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-01720.1-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1

---
 drivers/net/wireless/ath/ath11k/mac.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

index 97a2c92b7b9b..e015b22b8dbf 100644
@@ -2985,18 +2985,21 @@ void __ath11k_mac_scan_finish(struct ath11k *ar)
 		break;
 	case ATH11K_SCAN_RUNNING:
 	case ATH11K_SCAN_ABORTING:
+		if (ar->scan.is_roc && ar->scan.roc_notify)
+			ieee80211_remain_on_channel_expired(ar->hw);
+		fallthrough;
+	case ATH11K_SCAN_STARTING:
 		if (!ar->scan.is_roc) {
 			struct cfg80211_scan_info info = {
-				.aborted = (ar->scan.state ==
-					    ATH11K_SCAN_ABORTING),
+				.aborted = ((ar->scan.state ==
+					    ATH11K_SCAN_ABORTING) ||
+					    (ar->scan.state ==
+					    ATH11K_SCAN_STARTING)),
 			};
 
 			ieee80211_scan_completed(ar->hw, &info);
-		} else if (ar->scan.roc_notify) {
-			ieee80211_remain_on_channel_expired(ar->hw);
 		}
-		fallthrough;
-	case ATH11K_SCAN_STARTING:
+
 		ar->scan.state = ATH11K_SCAN_IDLE;
 		ar->scan_channel = NULL;
 		ar->scan.roc_freq = 0;

2.25.1

3 patches applied to ath-next branch of ath.git, thanks.

441b3b5911f8 ath11k: add handler for scan event WMI_SCAN_EVENT_DEQUEUED
c677d4b1bcc4 ath11k: indicate scan complete for scan canceled when scan running 62db14ea95b1 ath11k: indicate to mac80211 scan complete with aborted flag for ATH11K_SCAN_STARTING state

https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches

3 patches applied to ath-next branch of ath.git, thanks.

441b3b5911f8 ath11k: add handler for scan event WMI_SCAN_EVENT_DEQUEUED
c677d4b1bcc4 ath11k: indicate scan complete for scan canceled when scan running 62db14ea95b1 ath11k: indicate to mac80211 scan complete with aborted flag for ATH11K_SCAN_STARTING state

https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches


-- 
ath11k mailing list
[email protected]
http://lists.infradead.org/mailman/listinfo/ath11k