Prism54: Convert mgmt_sem to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/prism54/islpci_dev.c b/drivers/net/wireless/prism54/islpci_dev.c
index 219dd65..dbb538c 100644
--- a/drivers/net/wireless/prism54/islpci_dev.c
+++ b/drivers/net/wireless/prism54/islpci_dev.c
@@ -861,7 +861,7 @@
 	init_waitqueue_head(&priv->reset_done);
 
 	/* init the queue read locks, process wait counter */
-	sema_init(&priv->mgmt_sem, 1);
+	mutex_init(&priv->mgmt_lock);
 	priv->mgmt_received = NULL;
 	init_waitqueue_head(&priv->mgmt_wqueue);
 	sema_init(&priv->stats_sem, 1);
diff --git a/drivers/net/wireless/prism54/islpci_dev.h b/drivers/net/wireless/prism54/islpci_dev.h
index 736666d..4e0182c 100644
--- a/drivers/net/wireless/prism54/islpci_dev.h
+++ b/drivers/net/wireless/prism54/islpci_dev.h
@@ -26,6 +26,7 @@
 #include <linux/wireless.h>
 #include <net/iw_handler.h>
 #include <linux/list.h>
+#include <linux/mutex.h>
 
 #include "isl_38xx.h"
 #include "isl_oid.h"
@@ -164,7 +165,7 @@
 	wait_queue_head_t reset_done;
 
 	/* used by islpci_mgt_transaction */
-	struct semaphore mgmt_sem; /* serialize access to mailbox and wqueue */
+	struct mutex mgmt_lock; /* serialize access to mailbox and wqueue */
 	struct islpci_mgmtframe *mgmt_received;	  /* mbox for incoming frame */
 	wait_queue_head_t mgmt_wqueue;            /* waitqueue for mbox */
 
diff --git a/drivers/net/wireless/prism54/islpci_mgt.c b/drivers/net/wireless/prism54/islpci_mgt.c
index 2246f79..f7c677e 100644
--- a/drivers/net/wireless/prism54/islpci_mgt.c
+++ b/drivers/net/wireless/prism54/islpci_mgt.c
@@ -460,7 +460,7 @@
 
 	*recvframe = NULL;
 
-	if (down_interruptible(&priv->mgmt_sem))
+	if (mutex_lock_interruptible(&priv->mgmt_lock))
 		return -ERESTARTSYS;
 
 	prepare_to_wait(&priv->mgmt_wqueue, &wait, TASK_UNINTERRUPTIBLE);
@@ -504,7 +504,7 @@
 	/* TODO: we should reset the device here */
  out:
 	finish_wait(&priv->mgmt_wqueue, &wait);
-	up(&priv->mgmt_sem);
+	mutex_unlock(&priv->mgmt_lock);
 	return err;
 }