libertas: allow removal of card at any time

This fixes several problems I had:

* when removing the card while the card was scanning or associtating,
  it could happen that destroy_workqueue() stuck and didn't return.
* make sure the command function doesn't run while we remove the list
  of pending commands
* for still unknown reason, I had calls to lbs_stop_card() with
  priv==NULL

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/drivers/net/wireless/libertas/main.c b/drivers/net/wireless/libertas/main.c
index 223ab3a14a13..0be89573716c 100644
--- a/drivers/net/wireless/libertas/main.c
+++ b/drivers/net/wireless/libertas/main.c
@@ -1166,8 +1166,8 @@ void lbs_remove_card(struct lbs_private *priv)
 
         dev = priv->dev;
 
-        cancel_delayed_work(&priv->scan_work);
-        cancel_delayed_work(&priv->assoc_work);
+        cancel_delayed_work_sync(&priv->scan_work);
+        cancel_delayed_work_sync(&priv->assoc_work);
         destroy_workqueue(priv->work_thread);
 
         if (priv->psmode == LBS802_11POWERMODEMAX_PSP) {
@@ -1267,6 +1267,9 @@ void lbs_stop_card(struct lbs_private *priv)
 
         lbs_deb_enter(LBS_DEB_MAIN);
 
+        if (!priv)
+                goto out;
+
         netif_stop_queue(priv->dev);
         netif_carrier_off(priv->dev);
 
@@ -1276,6 +1279,7 @@ void lbs_stop_card(struct lbs_private *priv)
                 device_remove_file(&dev->dev, &dev_attr_lbs_mesh);
 
         /* Flush pending command nodes */
+        del_timer_sync(&priv->command_timer);
         spin_lock_irqsave(&priv->driver_lock, flags);
         list_for_each_entry(cmdnode, &priv->cmdpendingq, list) {
                 cmdnode->result = -ENOENT;
@@ -1286,6 +1290,7 @@ void lbs_stop_card(struct lbs_private *priv)
 
         unregister_netdev(dev);
 
+out:
         lbs_deb_leave(LBS_DEB_MAIN);
 }
 EXPORT_SYMBOL_GPL(lbs_stop_card);