wl12xx: wakeup chip from ELP during scan

Commands are sometimes sent to FW on scan completion. Make sure the chip
is awake to receive them. Sending commands while the chip is in ELP
can cause SDIO read errors and/or crash the FW.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Ido Yariv <ido@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>

drivers/net/wireless/wl12xx/cmd.c

@@ -63,6 +63,7 @@ int wl1271_cmd_send(struct wl1271 *wl, u16 id, void *buf, size_t len,
 	cmd->status = 0;
 
 	WARN_ON(len % 4 != 0);
+	WARN_ON(test_bit(WL1271_FLAG_IN_ELP, &wl->flags));
 
 	wl1271_write(wl, wl->cmd_box_addr, buf, len, false);
 

drivers/net/wireless/wl12xx/scan.c

@@ -27,6 +27,7 @@
 #include "cmd.h"
 #include "scan.h"
 #include "acx.h"
+#include "ps.h"
 
 void wl1271_scan_complete_work(struct work_struct *work)
 {
@@ -40,10 +41,11 @@ void wl1271_scan_complete_work(struct work_struct *work)
 
 	mutex_lock(&wl->mutex);
 
-	if (wl->scan.state == WL1271_SCAN_STATE_IDLE) {
-		mutex_unlock(&wl->mutex);
-		return;
-	}
+	if (wl->state == WL1271_STATE_OFF)
+		goto out;
+
+	if (wl->scan.state == WL1271_SCAN_STATE_IDLE)
+		goto out;
 
 	wl->scan.state = WL1271_SCAN_STATE_IDLE;
 	kfree(wl->scan.scanned_ch);
@@ -52,13 +54,19 @@ void wl1271_scan_complete_work(struct work_struct *work)
 	ieee80211_scan_completed(wl->hw, false);
 
 	/* restore hardware connection monitoring template */
-	if (test_bit(WL1271_FLAG_STA_ASSOCIATED, &wl->flags))
+	if (test_bit(WL1271_FLAG_STA_ASSOCIATED, &wl->flags)) {
+		if (wl1271_ps_elp_wakeup(wl) == 0) {
 			wl1271_cmd_build_ap_probe_req(wl, wl->probereq);
+			wl1271_ps_elp_sleep(wl);
+		}
+	}
 
 	if (wl->scan.failed) {
 		wl1271_info("Scan completed due to error.");
 		ieee80211_queue_work(wl->hw, &wl->recovery_work);
 	}
+
+out:
 	mutex_unlock(&wl->mutex);
 
 }