[IRDA]: stir4200, switching to the kthread API

stir4200 uses a kernel thread for its TX/RX operations, and it is now
converted to the kernel kthread API.
Tested on an STIR4200 based dongle.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Samuel Ortiz <samuel@sortiz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/irda/stir4200.c

@@ -50,6 +50,7 @@
 #include <linux/delay.h>
 #include <linux/usb.h>
 #include <linux/crc32.h>
+#include <linux/kthread.h>
 #include <net/irda/irda.h>
 #include <net/irda/irlap.h>
 #include <net/irda/irda_device.h>
@@ -173,9 +174,7 @@ struct stir_cb {
         struct qos_info   qos;
 	unsigned 	  speed;	/* Current speed */
 
-	wait_queue_head_t thr_wait;	/* transmit thread wakeup */
-	struct completion thr_exited;
-	pid_t		  thr_pid;
+        struct task_struct *thread;     /* transmit thread */
 
 	struct sk_buff	  *tx_pending;
 	void		  *io_buf;	/* transmit/receive buffer */
@@ -577,7 +576,7 @@ static int stir_hard_xmit(struct sk_buff *skb, struct net_device *netdev)
 	SKB_LINEAR_ASSERT(skb);
 
 	skb = xchg(&stir->tx_pending, skb);
-	wake_up(&stir->thr_wait);
+        wake_up_process(stir->thread);
 
 	/* this should never happen unless stop/wakeup problem */
 	if (unlikely(skb)) {
@@ -753,13 +752,7 @@ static int stir_transmit_thread(void *arg)
 	struct net_device *dev = stir->netdev;
 	struct sk_buff *skb;
 
-	daemonize("%s", dev->name);
-	allow_signal(SIGTERM);
-
-	while (netif_running(dev)
-	       && netif_device_present(dev)
-	       && !signal_pending(current))
-	{
+        while (!kthread_should_stop()) {
 #ifdef CONFIG_PM
 		/* if suspending, then power off and wait */
 		if (unlikely(freezing(current))) {
@@ -813,10 +806,11 @@ static int stir_transmit_thread(void *arg)
 		}
 
 		/* sleep if nothing to send */
-		wait_event_interruptible(stir->thr_wait, stir->tx_pending);
-	}
+                set_current_state(TASK_INTERRUPTIBLE);
+                schedule();
 
-	complete_and_exit (&stir->thr_exited, 0);
+	}
+        return 0;
 }
 
 
@@ -859,7 +853,7 @@ static void stir_rcv_irq(struct urb *urb, struct pt_regs *regs)
 		warn("%s: usb receive submit error: %d",
 			stir->netdev->name, err);
 		stir->receiving = 0;
-		wake_up(&stir->thr_wait);
+		wake_up_process(stir->thread);
 	}
 }
 
@@ -928,10 +922,10 @@ static int stir_net_open(struct net_device *netdev)
 	}
 
 	/** Start kernel thread for transmit.  */
-	stir->thr_pid = kernel_thread(stir_transmit_thread, stir,
-				      CLONE_FS|CLONE_FILES);
-	if (stir->thr_pid < 0) {
-		err = stir->thr_pid;
+	stir->thread = kthread_run(stir_transmit_thread, stir,
+				   "%s", stir->netdev->name);
+        if (IS_ERR(stir->thread)) {
+                err = PTR_ERR(stir->thread);
 		err("stir4200: unable to start kernel thread");
 		goto err_out6;
 	}
@@ -968,8 +962,7 @@ static int stir_net_close(struct net_device *netdev)
 	netif_stop_queue(netdev);
 
 	/* Kill transmit thread */
-	kill_proc(stir->thr_pid, SIGTERM, 1);
-	wait_for_completion(&stir->thr_exited);
+	kthread_stop(stir->thread);
 	kfree(stir->fifo_status);
 
 	/* Mop up receive urb's */
@@ -1084,9 +1077,6 @@ static int stir_probe(struct usb_interface *intf,
 	stir->qos.min_turn_time.bits   &= qos_mtt_bits;
 	irda_qos_bits_to_value(&stir->qos);
 
-	init_completion (&stir->thr_exited);
-	init_waitqueue_head (&stir->thr_wait);
-
 	/* Override the network functions we need to use */
 	net->hard_start_xmit = stir_hard_xmit;
 	net->open            = stir_net_open;