V4L/DVB (6691): pvrusb2: Rework pipeline state control

This is a new implementation for video pipeline control within the
pvrusb2 driver.  Actual start/stop of the pipeline is moved to the
driver's kernel thread.  Pipeline stages are controlled autonomously
based on surrounding pipeline or application control state.  Kernel
thread management is also cleaned up and moved into the internal
control structure of the driver, solving a set up / tear down race
along the way.  Better failure recovery is implemented with this new
control strategy.  Also with this change comes better control of the
cx23416 encoder, building on additional information learned about the
peculiarities of controlling this part (this information was the
original trigger for this rework).  With this change, overall encoder
stability should be considerably improved.  Yes, this is a large
change for this driver, but due to the nature of the feature being
worked on, the changes are fairly pervasive and would be difficult to
break into smaller pieces with any semblence of step-wise stability.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 17 insertions, 38 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-context.c b/drivers/media/video/pvrusb2/pvrusb2-context.c
index 22719ba861ac..9d94aed2e12d 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-context.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-context.c
@@ -31,52 +31,32 @@
 
 static void pvr2_context_destroy(struct pvr2_context *mp)
 {
-	if (mp->hdw) pvr2_hdw_destroy(mp->hdw);
 	pvr2_trace(PVR2_TRACE_STRUCT,"Destroying pvr_main id=%p",mp);
-	if (mp->workqueue) {
-		flush_workqueue(mp->workqueue);
-		destroy_workqueue(mp->workqueue);
-	}
+	if (mp->hdw) pvr2_hdw_destroy(mp->hdw);
 	kfree(mp);
 }
 
 
-static void pvr2_context_trigger_poll(struct pvr2_context *mp)
-{
-	queue_work(mp->workqueue,&mp->workpoll);
-}
-
-
-static void pvr2_context_poll(struct work_struct *work)
-{
-	struct pvr2_context *mp =
-		container_of(work, struct pvr2_context, workpoll);
-	pvr2_context_enter(mp); do {
-		pvr2_hdw_poll(mp->hdw);
-	} while (0); pvr2_context_exit(mp);
-}
-
-
-static void pvr2_context_setup(struct work_struct *work)
+static void pvr2_context_state_check(struct pvr2_context *mp)
 {
-	struct pvr2_context *mp =
-		container_of(work, struct pvr2_context, workinit);
+	if (mp->init_flag) return;
+
+	switch (pvr2_hdw_get_state(mp->hdw)) {
+	case PVR2_STATE_WARM: break;
+	case PVR2_STATE_ERROR: break;
+	case PVR2_STATE_READY: break;
+	case PVR2_STATE_RUN: break;
+	default: return;
+	}
 
 	pvr2_context_enter(mp); do {
-		if (!pvr2_hdw_dev_ok(mp->hdw)) break;
-		pvr2_hdw_setup(mp->hdw);
-		pvr2_hdw_setup_poll_trigger(
-			mp->hdw,
-			(void (*)(void *))pvr2_context_trigger_poll,
-			mp);
-		if (!pvr2_hdw_dev_ok(mp->hdw)) break;
-		if (!pvr2_hdw_init_ok(mp->hdw)) break;
+		mp->init_flag = !0;
 		mp->video_stream.stream = pvr2_hdw_get_video_stream(mp->hdw);
 		if (mp->setup_func) {
 			mp->setup_func(mp);
 		}
 	} while (0); pvr2_context_exit(mp);
-}
+ }
 
 
 struct pvr2_context *pvr2_context_create(
@@ -96,11 +76,10 @@ struct pvr2_context *pvr2_context_create(
 		mp = NULL;
 		goto done;
 	}
-
-	mp->workqueue = create_singlethread_workqueue("pvrusb2");
-	INIT_WORK(&mp->workinit, pvr2_context_setup);
-	INIT_WORK(&mp->workpoll, pvr2_context_poll);
-	queue_work(mp->workqueue,&mp->workinit);
+	pvr2_hdw_set_state_callback(mp->hdw,
+				    (void (*)(void *))pvr2_context_state_check,
+				    mp);
+	pvr2_context_state_check(mp);
  done:
 	return mp;
 }