Staging: dt3155v4l: correcting a bug

dt3155v4l driver, as in -rc6-next-20100506 has a BUG.
When it modifies q->int_ops structure in videobuf-dma-contig
module the change is visible for all other modules using it.

Make a local copy of this structure and use its modification
to solve the bug.

Signed-off-by: Marin Mitov <mitov@issp.bas.bg>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/dt3155v4l/dt3155v4l.c

@@ -612,9 +612,14 @@ dt3155_queue_dma_contig_init(struct videobuf_queue *q,
 					unsigned int msize,
 					void *priv)
 {
+	struct dt3155_priv *pd = q->priv_data;
+
 	videobuf_queue_dma_contig_init(q, ops, dev, irqlock,
 				       type, field, msize, priv);
-	/* overwrite with our methods */
+	/* replace with local copy */
+	pd->qt_ops = *q->int_ops;
+	q->int_ops = &pd->qt_ops;
+	/* and overwrite with our methods */
 	q->int_ops->iolock = dt3155_iolock;
 	q->int_ops->mmap_mapper = dt3155_mmap_mapper;
 	q->int_ops->sync = dt3155_sync_for_cpu;

drivers/staging/dt3155v4l/dt3155v4l.h

@@ -185,6 +185,7 @@ struct dt3155_stats {
  * @curr_buf:		pointer to curren buffer
  * @thread		pointer to worker thraed
  * @irq_handler:	irq handler for the driver
+ * @qt_ops		local copy of dma-contig qtype_ops
  * @dmaq		queue for dma buffers
  * @do_dma		wait queue of the kernel thread
  * @mux:		mutex to protect the instance
@@ -204,6 +205,7 @@ struct dt3155_priv {
 	struct videobuf_buffer *curr_buf;
 	struct task_struct *thread;
 	irq_handler_t irq_handler;
+	struct videobuf_qtype_ops qt_ops;
 	struct list_head dmaq;
 	wait_queue_head_t do_dma;
 	struct mutex mux;