Add the following functions to abstract away the creation of task threads

for usb.  I hope that this will eventually be used for generic devices
that need full fledged blocking threads for event processing.

Create a taskqueue:
void usb_ether_task_init(device_t, int, struct usb_taskqueue *);

Enqueue a task:
void usb_ether_task_enqueue(struct usb_taskqueue *, struct task *);

Wait for all tasks queued to complete:
void usb_ether_task_drain(struct usb_taskqueue *, struct task *);

Destroy the taskqueue:
void usb_ether_task_destroy(struct usb_taskqueue *);

2 files changed, 39 insertions, 0 deletions

diff --git a/sys/dev/usb/usb_ethersubr.c b/sys/dev/usb/usb_ethersubr.c
index ef43cdb..2cb5fa6 100644
--- a/sys/dev/usb/usb_ethersubr.c
+++ b/sys/dev/usb/usb_ethersubr.c
@@ -57,6 +57,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/mbuf.h>
 #include <sys/malloc.h>
 #include <sys/socket.h>
+#include <sys/taskqueue.h>
 
 #include <net/if.h>
 #include <net/if_types.h>
@@ -246,3 +247,32 @@ usb_ether_tx_list_free(struct ue_cdata *cd)
 		}
 	}
 }
+
+void
+usb_ether_task_init(device_t dev, int flags, struct usb_taskqueue *tq)
+{
+
+	/* nothing for now. */
+}
+
+void
+usb_ether_task_enqueue(struct usb_taskqueue *tq, struct task *task)
+{
+
+	taskqueue_enqueue(taskqueue_thread, task);
+}
+
+void
+usb_ether_task_drain(struct usb_taskqueue *tq, struct task *task)
+{
+
+	taskqueue_drain(taskqueue_thread, task);
+}
+
+void
+usb_ether_task_destroy(struct usb_taskqueue *tq)
+{
+
+	/* nothing for now */
+
+}
diff --git a/sys/dev/usb/usb_ethersubr.h b/sys/dev/usb/usb_ethersubr.h
index cd4acc1..f3d2e34 100644
--- a/sys/dev/usb/usb_ethersubr.h
+++ b/sys/dev/usb/usb_ethersubr.h
@@ -79,4 +79,13 @@ int usb_ether_tx_list_init	(void *, struct ue_cdata *,
 void usb_ether_rx_list_free	(struct ue_cdata *);
 void usb_ether_tx_list_free	(struct ue_cdata *);
 
+struct usb_taskqueue {
+	int dummy;
+};
+
+void usb_ether_task_init(device_t, int, struct usb_taskqueue *);
+void usb_ether_task_enqueue(struct usb_taskqueue *, struct task *);
+void usb_ether_task_drain(struct usb_taskqueue *, struct task *);
+void usb_ether_task_destroy(struct usb_taskqueue *);
+
 #endif /* _USB_ETHERSUBR_H_ */