ath6kl: Check wow state before sending control and data pkt

Below two scenarios are taken care in this patch which helped
to fix the firmware crash during wow suspend/resume.

* TX operation (ctrl tx and data tx) has to be controlled based
  on suspend state. i.e, with respect to WOW mode, control packets
  are allowed to send from the host until the suspend state goes
  ATH6KL_STATE_WOW and the data packets are allowed until WOW
  suspend operation starts.

* Similarly, wow resume is NOT allowed if WOW suspend is in progress.
Signed-off-by: NRaja Mani <rmani@qca.qualcomm.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath6kl/cfg80211.c

@@ -1948,6 +1948,10 @@ static int ath6kl_wow_suspend(struct ath6kl *ar, struct cfg80211_wowlan *wow)
 	if (ret)
 		return ret;
 
+	netif_stop_queue(vif->ndev);
+
+	ar->state = ATH6KL_STATE_SUSPENDING;
+
 	/* Setup own IP addr for ARP agent. */
 	in_dev = __in_dev_get_rtnl(vif->ndev);
 	if (!in_dev)
@@ -2026,15 +2030,29 @@ static int ath6kl_wow_resume(struct ath6kl *ar)
 	if (!vif)
 		return -EIO;
 
+	ar->state = ATH6KL_STATE_RESUMING;
+
 	ret = ath6kl_wmi_set_host_sleep_mode_cmd(ar->wmi, vif->fw_vif_idx,
 						 ATH6KL_HOST_MODE_AWAKE);
-	return ret;
+	if (ret) {
+		ath6kl_warn("Failed to configure host sleep mode for "
+			    "wow resume: %d\n", ret);
+		ar->state = ATH6KL_STATE_WOW;
+		return ret;
+	}
+
+	ar->state = ATH6KL_STATE_ON;
+
+	netif_wake_queue(vif->ndev);
+
+	return 0;
 }
 
 int ath6kl_cfg80211_suspend(struct ath6kl *ar,
 			    enum ath6kl_cfg_suspend_mode mode,
 			    struct cfg80211_wowlan *wow)
 {
+	enum ath6kl_state prev_state;
 	int ret;
 
 	switch (mode) {
@@ -2045,9 +2063,13 @@ int ath6kl_cfg80211_suspend(struct ath6kl *ar,
 		/* Flush all non control pkts in TX path */
 		ath6kl_tx_data_cleanup(ar);
 
+		prev_state = ar->state;
+
 		ret = ath6kl_wow_suspend(ar, wow);
-		if (ret)
+		if (ret) {
+			ar->state = prev_state;
 			return ret;
+		}
 
 		ar->state = ATH6KL_STATE_WOW;
 		break;
@@ -2120,7 +2142,6 @@ int ath6kl_cfg80211_resume(struct ath6kl *ar)
 			return ret;
 		}
 
-		ar->state = ATH6KL_STATE_ON;
 		break;
 
 	case ATH6KL_STATE_DEEPSLEEP:
@@ -2194,6 +2215,9 @@ static int __ath6kl_cfg80211_resume(struct wiphy *wiphy)
  */
 void ath6kl_check_wow_status(struct ath6kl *ar)
 {
+	if (ar->state == ATH6KL_STATE_SUSPENDING)
+		return;
+
 	if (ar->state == ATH6KL_STATE_WOW)
 		ath6kl_cfg80211_resume(ar);
 }

drivers/net/wireless/ath/ath6kl/core.h

@@ -537,6 +537,8 @@ enum ath6kl_dev_state {
 enum ath6kl_state {
 	ATH6KL_STATE_OFF,
 	ATH6KL_STATE_ON,
+	ATH6KL_STATE_SUSPENDING,
+	ATH6KL_STATE_RESUMING,
 	ATH6KL_STATE_DEEPSLEEP,
 	ATH6KL_STATE_CUTPOWER,
 	ATH6KL_STATE_WOW,

drivers/net/wireless/ath/ath6kl/sdio.c

@@ -932,8 +932,15 @@ static int ath6kl_sdio_resume(struct ath6kl *ar)
 
 	case ATH6KL_STATE_WOW:
 		break;
+
 	case ATH6KL_STATE_SCHED_SCAN:
 		break;
+
+	case ATH6KL_STATE_SUSPENDING:
+		break;
+
+	case ATH6KL_STATE_RESUMING:
+		break;
 	}
 
 	ath6kl_cfg80211_resume(ar);

drivers/net/wireless/ath/ath6kl/txrx.c

@@ -285,6 +285,9 @@ int ath6kl_control_tx(void *devt, struct sk_buff *skb,
 	int status = 0;
 	struct ath6kl_cookie *cookie = NULL;
 
+	if (WARN_ON_ONCE(ar->state == ATH6KL_STATE_WOW))
+		return -EACCES;
+
 	spin_lock_bh(&ar->lock);
 
 	ath6kl_dbg(ATH6KL_DBG_WLAN_TX,
@@ -360,6 +363,11 @@ int ath6kl_data_tx(struct sk_buff *skb, struct net_device *dev)
 		return 0;
 	}
 
+	if (WARN_ON_ONCE(ar->state != ATH6KL_STATE_ON)) {
+		dev_kfree_skb(skb);
+		return 0;
+	}
+
 	if (!test_bit(WMI_READY, &ar->flag))
 		goto fail_tx;