[PATCHv8 09/26] v4l: vb2: add prepare/finish callbacks to allocators

[Tomasz Stanislawski <t.stanislaws@samsung.com>]

From: Marek Szyprowski <m.szyprowski@samsung.com>

This patch adds support for prepare/finish callbacks in VB2 allocators. These
callback are used for buffer flushing.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
 drivers/media/video/videobuf2-core.c |   11 +++++++++++
 include/media/videobuf2-core.h       |    7 +++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/media/video/videobuf2-core.c b/drivers/media/video/videobuf2-core.c
index a5d5081..aed21e4 100644
--- a/drivers/media/video/videobuf2-core.c
+++ b/drivers/media/video/videobuf2-core.c
@@ -850,6 +850,7 @@ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state)
 {
 	struct vb2_queue *q = vb->vb2_queue;
 	unsigned long flags;
+	unsigned int plane;
 
 	if (vb->state != VB2_BUF_STATE_ACTIVE)
 		return;
@@ -860,6 +861,10 @@ void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state)
 	dprintk(4, "Done processing on buffer %d, state: %d\n",
 			vb->v4l2_buf.index, vb->state);
 
+	/* sync buffers */
+	for (plane = 0; plane < vb->num_planes; ++plane)
+		call_memop(q, finish, vb->planes[plane].mem_priv);
+
 	/* Add the buffer to the done buffers list */
 	spin_lock_irqsave(&q->done_lock, flags);
 	vb->state = state;
@@ -1138,9 +1143,15 @@ err:
 static void __enqueue_in_driver(struct vb2_buffer *vb)
 {
 	struct vb2_queue *q = vb->vb2_queue;
+	unsigned int plane;
 
 	vb->state = VB2_BUF_STATE_ACTIVE;
 	atomic_inc(&q->queued_count);
+
+	/* sync buffers */
+	for (plane = 0; plane < vb->num_planes; ++plane)
+		call_memop(q, prepare, vb->planes[plane].mem_priv);
+
 	q->ops->buf_queue(vb);
 }
 
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index 84f11f2..c306fec 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -56,6 +56,10 @@ struct vb2_fileio_data;
  *		dmabuf
  * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified
  *		  that this driver is done using the dmabuf for now
+ * @prepare:	called everytime the buffer is passed from userspace to the
+ *		driver, usefull for cache synchronisation, optional
+ * @finish:	called everytime the buffer is passed back from the driver
+ *		to the userspace, also optional
  * @vaddr:	return a kernel virtual address to a given memory buffer
  *		associated with the passed private structure or NULL if no
  *		such mapping exists
@@ -82,6 +86,9 @@ struct vb2_mem_ops {
 					unsigned long size, int write);
 	void		(*put_userptr)(void *buf_priv);
 
+	void		(*prepare)(void *buf_priv);
+	void		(*finish)(void *buf_priv);
+
 	void		*(*attach_dmabuf)(void *alloc_ctx, struct dma_buf *dbuf,
 				unsigned long size, int write);
 	void		(*detach_dmabuf)(void *buf_priv);
-- 
1.7.9.5