softmac: avoid assert in ieee80211softmac_wx_get_rate

[PATCH] softmac: avoid assert in ieee80211softmac_wx_get_rate

Unconfigured bcm43xx device can hit an assert() during wx_get_rate
queries.  This is because bcm43xx calls ieee80211softmac_start late
(i.e. during open instead of probe).

   bcm43xx_net_open ->
      bcm43xx_init_board ->
         bcm43xx_select_wireless_core ->
            ieee80211softmac_start

Fix is to check that device is running before completing
ieee80211softmac_wx_get_rate.
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

net/ieee80211/softmac/ieee80211softmac_wx.c

@@ -265,6 +265,12 @@ ieee80211softmac_wx_get_rate(struct net_device *net_dev,
 	int err = -EINVAL;
 
 	spin_lock_irqsave(&mac->lock, flags);
+
+	if (unlikely(!mac->running)) {
+		err = -ENODEV;
+		goto out_unlock;
+	}
+
 	switch (mac->txrates.default_rate) {
 	case IEEE80211_CCK_RATE_1MB:
 		data->bitrate.value = 1000000;