[media] solo6x10: convert the display node to vb2

As a consequence the ioctl op has been replaced by unlocked_ioctl.
Since we are now using the core lock the locking scheme has been
simplified as well.
The main reason for converting this driver to vb2 was that the locking
scheme in v4l2.c was hopeless. It was easier to just convert the driver
then to try and salvage a threading and videobuf nightmare.
The videobuf2 framework is far, far superior compared to the old videobuf.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/solo6x10/Kconfig

@@ -1,8 +1,8 @@
 config SOLO6X10
 	tristate "Softlogic 6x10 MPEG codec cards"
 	depends on PCI && VIDEO_DEV && SND && I2C
-	select VIDEOBUF_DMA_SG
 	select VIDEOBUF2_DMA_SG
+	select VIDEOBUF2_DMA_CONTIG
 	select SND_PCM
 	---help---
 	  This driver supports the Softlogic based MPEG-4 and h.264 codec

drivers/staging/media/solo6x10/solo6x10.h

@@ -39,7 +39,6 @@
 #include <media/v4l2-dev.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-ctrls.h>
-#include <media/videobuf-core.h>
 #include <media/videobuf2-core.h>
 
 #include "registers.h"
@@ -259,17 +258,17 @@ struct solo_dev {
 	/* Ring thread */
 	struct task_struct	*ring_thread;
 	wait_queue_head_t	ring_thread_wait;
-	atomic_t		enc_users;
-	atomic_t		disp_users;
 
 	/* VOP_HEADER handling */
 	void                    *vh_buf;
 	dma_addr_t		vh_dma;
 	int			vh_size;
 
 	/* Buffer handling */
-	struct videobuf_queue	vidq;
+	struct vb2_queue	vidq;
+	struct vb2_alloc_ctx	*alloc_ctx;
 	struct task_struct      *kthread;
+	struct mutex		lock;
 	spinlock_t		slock;
 	int			old_write;
 	struct list_head	vidq_active;

drivers/staging/media/solo6x10/v4l2-enc.c

@@ -41,11 +41,6 @@
 #define MP4_QS			16
 #define DMA_ALIGN		4096
 
-struct solo_videobuf {
-	struct videobuf_buffer	vb;
-	unsigned int		flags;
-};
-
 /* 6010 M4V */
 static unsigned char vop_6010_ntsc_d1[] = {
 	0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01, 0x20,
@@ -672,9 +667,6 @@ static void solo_enc_buf_queue(struct vb2_buffer *vb)
 
 static int solo_ring_start(struct solo_dev *solo_dev)
 {
-	if (atomic_inc_return(&solo_dev->enc_users) > 1)
-		return 0;
-
 	solo_dev->ring_thread = kthread_run(solo_ring_thread, solo_dev,
 					    SOLO6X10_NAME "_ring");
 	if (IS_ERR(solo_dev->ring_thread)) {
@@ -690,9 +682,6 @@ static int solo_ring_start(struct solo_dev *solo_dev)
 
 static void solo_ring_stop(struct solo_dev *solo_dev)
 {
-	if (atomic_dec_return(&solo_dev->enc_users) > 0)
-		return;
-
 	if (solo_dev->ring_thread) {
 		kthread_stop(solo_dev->ring_thread);
 		solo_dev->ring_thread = NULL;
@@ -1279,7 +1268,6 @@ int solo_enc_v4l2_init(struct solo_dev *solo_dev, unsigned nr)
 {
 	int i;
 
-	atomic_set(&solo_dev->enc_users, 0);
 	init_waitqueue_head(&solo_dev->ring_thread_wait);
 
 	solo_dev->vh_size = sizeof(struct vop_header);