wlcore: block read/writes to FW during ELP

When the chip is in ELP mode read/write to FW is invalid and may cause
the lower layers to get stuck. The reads/writes concerning ELP wakeup
are the exception here and are checked for. In addition to blocking the
IO, produce a warning.
Signed-off-by: Barak Bercovitz <barak@wizery.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ti/wlcore/io.h

@@ -60,7 +60,9 @@ static inline int __must_check wlcore_raw_write(struct wl1271 *wl, int addr,
 {
 	int ret;
 
-	if (test_bit(WL1271_FLAG_IO_FAILED, &wl->flags))
+	if (test_bit(WL1271_FLAG_IO_FAILED, &wl->flags) ||
+	    WARN_ON((test_bit(WL1271_FLAG_IN_ELP, &wl->flags) &&
+		     addr != HW_ACCESS_ELP_CTRL_REG)))
 		return -EIO;
 
 	ret = wl->if_ops->write(wl->dev, addr, buf, len, fixed);
@@ -76,7 +78,9 @@ static inline int __must_check wlcore_raw_read(struct wl1271 *wl, int addr,
 {
 	int ret;
 
-	if (test_bit(WL1271_FLAG_IO_FAILED, &wl->flags))
+	if (test_bit(WL1271_FLAG_IO_FAILED, &wl->flags) ||
+	    WARN_ON((test_bit(WL1271_FLAG_IN_ELP, &wl->flags) &&
+		     addr != HW_ACCESS_ELP_CTRL_REG)))
 		return -EIO;
 
 	ret = wl->if_ops->read(wl->dev, addr, buf, len, fixed);