media: rcar-vin: Move hardware buffer tracking to own struct

To support SEQ_TB/BT not all buffers given to the hardware will be
equal, the driver needs to keep track of different buffer types. Move
the tracking of buffers given to hardware into a struct so additional
tracking fields can be associated with each buffer.

[hverkuil: fix small checkpatch warning]

Signed-off-by: Niklas Söderlund <[e-mail]>
Signed-off-by: Hans Verkuil <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/platform/rcar-vin/rcar-dma.c

···
 	dma_addr_t phys_addr;
 
 	/* A already populated slot shall never be overwritten. */
-	if (WARN_ON(vin->queue_buf[slot] != NULL))
+	if (WARN_ON(vin->buf_hw[slot].buffer))
 		return;
 
 	vin_dbg(vin, "Filling HW slot: %d\n", slot);
 
 	if (list_empty(&vin->buf_list)) {
-		vin->queue_buf[slot] = NULL;
+		vin->buf_hw[slot].buffer = NULL;
 		phys_addr = vin->scratch_phys;
 	} else {
 		/* Keep track of buffer we give to HW */
 		buf = list_entry(vin->buf_list.next, struct rvin_buffer, list);
 		vbuf = &buf->vb;
 		list_del_init(to_buf_list(vbuf));
-		vin->queue_buf[slot] = vbuf;
+		vin->buf_hw[slot].buffer = vbuf;
 
 		/* Setup DMA */
 		phys_addr = vb2_dma_contig_plane_dma_addr(&vbuf->vb2_buf, 0);
···
 	}
 
 	/* Capture frame */
-	if (vin->queue_buf[slot]) {
-		vin->queue_buf[slot]->field = rvin_get_active_field(vin, vnms);
-		vin->queue_buf[slot]->sequence = vin->sequence;
-		vin->queue_buf[slot]->vb2_buf.timestamp = ktime_get_ns();
-		vb2_buffer_done(&vin->queue_buf[slot]->vb2_buf,
+	if (vin->buf_hw[slot].buffer) {
+		vin->buf_hw[slot].buffer->field =
+			rvin_get_active_field(vin, vnms);
+		vin->buf_hw[slot].buffer->sequence = vin->sequence;
+		vin->buf_hw[slot].buffer->vb2_buf.timestamp = ktime_get_ns();
+		vb2_buffer_done(&vin->buf_hw[slot].buffer->vb2_buf,
 				VB2_BUF_STATE_DONE);
-		vin->queue_buf[slot] = NULL;
+		vin->buf_hw[slot].buffer = NULL;
 	} else {
 		/* Scratch buffer was used, dropping frame. */
 		vin_dbg(vin, "Dropping frame %u\n", vin->sequence);
···
 	int i;
 
 	for (i = 0; i < HW_BUFFER_NUM; i++) {
-		if (vin->queue_buf[i]) {
-			vb2_buffer_done(&vin->queue_buf[i]->vb2_buf,
+		if (vin->buf_hw[i].buffer) {
+			vb2_buffer_done(&vin->buf_hw[i].buffer->vb2_buf,
 					state);
-			vin->queue_buf[i] = NULL;
+			vin->buf_hw[i].buffer = NULL;
 		}
 	}
 
···
 	vin->state = STOPPED;
 
 	for (i = 0; i < HW_BUFFER_NUM; i++)
-		vin->queue_buf[i] = NULL;
+		vin->buf_hw[i].buffer = NULL;
 
 	/* buffer queue */
 	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

drivers/media/platform/rcar-vin/rcar-vin.h

···
  * @scratch:		cpu address for scratch buffer
  * @scratch_phys:	physical address of the scratch buffer
  *
- * @qlock:		protects @queue_buf, @buf_list, @sequence
- *			@state
- * @queue_buf:		Keeps track of buffers given to HW slot
+ * @qlock:		protects @buf_hw, @buf_list, @sequence and @state
+ * @buf_hw:		Keeps track of buffers given to HW slot
  * @buf_list:		list of queued buffers
  * @sequence:		V4L2 buffers sequence number
  * @state:		keeps track of operation state
···
 	dma_addr_t scratch_phys;
 
 	spinlock_t qlock;
-	struct vb2_v4l2_buffer *queue_buf[HW_BUFFER_NUM];
+	struct {
+		struct vb2_v4l2_buffer *buffer;
+	} buf_hw[HW_BUFFER_NUM];
 	struct list_head buf_list;
 	unsigned int sequence;
 	enum rvin_dma_state state;