patches/collateral-evolutions/network/75-cw1200-workqueues/cw1200_workqueues.patch

--- a/drivers/net/wireless/cw1200/bh.c
+++ b/drivers/net/wireless/cw1200/bh.c
@@ -48,16 +48,22 @@ enum cw1200_bh_pm_state {
 typedef int (*cw1200_wsm_handler)(struct cw1200_common *priv,
 	u8 *data, size_t size);
 
+#ifndef CW1200_USE_COMPAT_KTHREAD
 static void cw1200_bh_work(struct work_struct *work)
 {
 	struct cw1200_common *priv =
 	container_of(work, struct cw1200_common, bh_work);
 	cw1200_bh(priv);
 }
+#endif
 
 int cw1200_register_bh(struct cw1200_common *priv)
 {
 	int err = 0;
+#ifdef CW1200_USE_COMPAT_KTHREAD
+	struct sched_param param = { .sched_priority = 1 };
+	BUG_ON(priv->bh_thread);
+#else
 	/* Realtime workqueue */
 	priv->bh_workqueue = alloc_workqueue("cw1200_bh",
 				WQ_MEM_RECLAIM | WQ_HIGHPRI
@@ -67,6 +73,7 @@ int cw1200_register_bh(struct cw1200_com
 		return -ENOMEM;
 
 	INIT_WORK(&priv->bh_work, cw1200_bh_work);
+#endif
 
 	pr_debug("[BH] register.\n");
 
@@ -81,20 +88,44 @@ int cw1200_register_bh(struct cw1200_com
 	init_waitqueue_head(&priv->bh_wq);
 	init_waitqueue_head(&priv->bh_evt_wq);
 
+#ifdef CW1200_USE_COMPAT_KTHREAD
+	priv->bh_thread = kthread_create(&cw1200_bh, priv, "cw1200_bh");
+	if (IS_ERR(priv->bh_thread)) {
+		err = PTR_ERR(priv->bh_thread);
+		priv->bh_thread = NULL;
+	} else {
+		WARN_ON(sched_setscheduler(priv->bh_thread,
+					   SCHED_FIFO, &param));
+		wake_up_process(priv->bh_thread);
+	}
+#else
 	err = !queue_work(priv->bh_workqueue, &priv->bh_work);
 	WARN_ON(err);
+#endif
+
 	return err;
 }
 
 void cw1200_unregister_bh(struct cw1200_common *priv)
 {
+#ifdef CW1200_USE_COMPAT_KTHREAD
+	struct task_struct *thread = priv->bh_thread;
+	if (WARN_ON(!thread))
+		return;
+#endif
+
 	atomic_add(1, &priv->bh_term);
 	wake_up(&priv->bh_wq);
 
+#ifdef CW1200_USE_COMPAT_KTHREAD
+	kthread_stop(thread);
+	priv->bh_thread = NULL;
+#else
 	flush_workqueue(priv->bh_workqueue);
 
 	destroy_workqueue(priv->bh_workqueue);
 	priv->bh_workqueue = NULL;
+#endif
 
 	pr_debug("[BH] unregistered.\n");
 }
@@ -614,6 +645,16 @@ static int cw1200_bh(void *arg)
 		pr_err("[BH] Fatal error, exiting.\n");
 		priv->bh_error = 1;
 		/* TODO: schedule_work(recovery) */
+#ifdef CW1200_USE_COMPAT_KTHREAD
+		for (;;) {
+			int status = wait_event_interruptible(priv->bh_wq, ({
+				term = atomic_xchg(&priv->bh_term, 0);
+				(term);
+			}));
+		if (status || term)
+			break;
+	}
+#endif
 	}
 	return 0;
 }
--- a/drivers/net/wireless/cw1200/cw1200.h
+++ b/drivers/net/wireless/cw1200/cw1200.h
@@ -23,12 +23,18 @@
 #include <linux/workqueue.h>
 #include <net/mac80211.h>
 
+#include <linux/version.h>
+
 #include "queue.h"
 #include "wsm.h"
 #include "scan.h"
 #include "txrx.h"
 #include "pm.h"
 
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 36))
+#define CW1200_USE_COMPAT_KTHREAD
+#endif
+
 /* Forward declarations */
 struct hwbus_ops;
 struct task_struct;
@@ -190,8 +196,12 @@ struct cw1200_common {
 	atomic_t			bh_term;
 	atomic_t			bh_suspend;
 
+#ifdef CW1200_USE_COMPAT_KTHREAD
+	struct task_struct              *bh_thread;
+#else
 	struct workqueue_struct         *bh_workqueue;
 	struct work_struct              bh_work;
+#endif
 
 	int				bh_error;
 	wait_queue_head_t		bh_wq;