wl12xx: implement SW Tx watchdog

Track freed FW blocks during Tx. If no blocks were freed during a
predefined timeout, initiate a HW recovery. This helps in situations
when the FW watchdog fails.

Don't trigger recovery during activities that can temporarily stop
Tx. This includes:
- scanning
- buffering packets for sleeping stations (AP role)
- ROC on any role

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>
diff --git a/drivers/net/wireless/wl12xx/scan.c b/drivers/net/wireless/wl12xx/scan.c
index e43a6b2..fcba055 100644
--- a/drivers/net/wireless/wl12xx/scan.c
+++ b/drivers/net/wireless/wl12xx/scan.c
@@ -55,6 +55,12 @@
 	vif = wl->scan_vif;
 	wlvif = wl12xx_vif_to_data(vif);
 
+	/*
+	 * Rearm the tx watchdog just before idling scan. This
+	 * prevents just-finished scans from triggering the watchdog
+	 */
+	wl12xx_rearm_tx_watchdog_locked(wl);
+
 	wl->scan.state = WL1271_SCAN_STATE_IDLE;
 	memset(wl->scan.scanned_ch, 0, sizeof(wl->scan.scanned_ch));
 	wl->scan.req = NULL;