media: rcar-vin: Add support for V4L2_FIELD_SEQ_{TB,BT}

The hardware does not support capturing the field types
V4L2_FIELD_SEQ_TB and V4L2_FIELD_SEQ_BT. To capture in these formats the
driver needs to adjust the offset of the capture buffer and capture
twice to each vb2 buffer.

Signed-off-by: Niklas Söderlund <[e-mail]>
Reviewed-by: Jacopo Mondi <[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

···
 
 	/* Set scaling coefficient */
 	crop_height = vin->crop.height;
-	if (V4L2_FIELD_IS_INTERLACED(vin->format.field))
+	if (V4L2_FIELD_HAS_BOTH(vin->format.field))
 		crop_height *= 2;
 
 	ys = 0;
···
 	rvin_write(vin, 0, VNSLPOC_REG);
 	rvin_write(vin, vin->format.width - 1, VNEPPOC_REG);
 
-	if (V4L2_FIELD_IS_INTERLACED(vin->format.field))
+	if (V4L2_FIELD_HAS_BOTH(vin->format.field))
 		rvin_write(vin, vin->format.height / 2 - 1, VNELPOC_REG);
 	else
 		rvin_write(vin, vin->format.height - 1, VNELPOC_REG);
···
 	case V4L2_FIELD_INTERLACED_BT:
 		vnmc = VNMC_IM_FULL | VNMC_FOC;
 		break;
+	case V4L2_FIELD_SEQ_TB:
+	case V4L2_FIELD_SEQ_BT:
 	case V4L2_FIELD_NONE:
 		vnmc = VNMC_IM_ODD_EVEN;
 		progressive = true;
···
 	struct rvin_buffer *buf;
 	struct vb2_v4l2_buffer *vbuf;
 	dma_addr_t phys_addr;
+	int prev;
 
 	/* A already populated slot shall never be overwritten. */
 	if (WARN_ON(vin->buf_hw[slot].buffer))
 		return;
 
-	vin_dbg(vin, "Filling HW slot: %d\n", slot);
+	prev = (slot == 0 ? HW_BUFFER_NUM : slot) - 1;
 
-	if (list_empty(&vin->buf_list)) {
+	if (vin->buf_hw[prev].type == HALF_TOP) {
+		vbuf = vin->buf_hw[prev].buffer;
+		vin->buf_hw[slot].buffer = vbuf;
+		vin->buf_hw[slot].type = HALF_BOTTOM;
+		switch (vin->format.pixelformat) {
+		case V4L2_PIX_FMT_NV12:
+		case V4L2_PIX_FMT_NV16:
+			phys_addr = vin->buf_hw[prev].phys +
+				vin->format.sizeimage / 4;
+			break;
+		default:
+			phys_addr = vin->buf_hw[prev].phys +
+				vin->format.sizeimage / 2;
+			break;
+		}
+	} else if (list_empty(&vin->buf_list)) {
 		vin->buf_hw[slot].buffer = NULL;
+		vin->buf_hw[slot].type = FULL;
 		phys_addr = vin->scratch_phys;
 	} else {
 		/* Keep track of buffer we give to HW */
···
 		list_del_init(to_buf_list(vbuf));
 		vin->buf_hw[slot].buffer = vbuf;
 
+		vin->buf_hw[slot].type =
+			V4L2_FIELD_IS_SEQUENTIAL(vin->format.field) ?
+			HALF_TOP : FULL;
+
 		/* Setup DMA */
 		phys_addr = vb2_dma_contig_plane_dma_addr(&vbuf->vb2_buf, 0);
 	}
 
+	vin_dbg(vin, "Filling HW slot: %d type: %d buffer: %p\n",
+		slot, vin->buf_hw[slot].type, vin->buf_hw[slot].buffer);
+
+	vin->buf_hw[slot].phys = phys_addr;
 	rvin_set_slot_addr(vin, slot, phys_addr);
 }
 
 static int rvin_capture_start(struct rvin_dev *vin)
 {
 	int slot, ret;
+
+	for (slot = 0; slot < HW_BUFFER_NUM; slot++) {
+		vin->buf_hw[slot].buffer = NULL;
+		vin->buf_hw[slot].type = FULL;
+	}
 
 	for (slot = 0; slot < HW_BUFFER_NUM; slot++)
 		rvin_fill_hw_slot(vin, slot);
···
 
 	/* Capture frame */
 	if (vin->buf_hw[slot].buffer) {
+		/*
+		 * Nothing to do but refill the hardware slot if
+		 * capture only filled first half of vb2 buffer.
+		 */
+		if (vin->buf_hw[slot].type == HALF_TOP) {
+			vin->buf_hw[slot].buffer = NULL;
+			rvin_fill_hw_slot(vin, slot);
+			goto done;
+		}
+
 		vin->buf_hw[slot].buffer->field =
 			rvin_get_active_field(vin, vnms);
 		vin->buf_hw[slot].buffer->sequence = vin->sequence;
···
 			       enum vb2_buffer_state state)
 {
 	struct rvin_buffer *buf, *node;
-	int i;
+	struct vb2_v4l2_buffer *freed[HW_BUFFER_NUM];
+	unsigned int i, n;
 
 	for (i = 0; i < HW_BUFFER_NUM; i++) {
-		if (vin->buf_hw[i].buffer) {
-			vb2_buffer_done(&vin->buf_hw[i].buffer->vb2_buf,
-					state);
-			vin->buf_hw[i].buffer = NULL;
+		freed[i] = vin->buf_hw[i].buffer;
+		vin->buf_hw[i].buffer = NULL;
+
+		for (n = 0; n < i; n++) {
+			if (freed[i] == freed[n]) {
+				freed[i] = NULL;
+				break;
+			}
 		}
+
+		if (freed[i])
+			vb2_buffer_done(&freed[i]->vb2_buf, state);
 	}
 
 	list_for_each_entry_safe(buf, node, &vin->buf_list, list) {

drivers/media/platform/rcar-vin/rcar-v4l2.c

···
 		break;
 	}
 
+	if (V4L2_FIELD_IS_SEQUENTIAL(pix->field))
+		align = 0x80;
+
 	return ALIGN(pix->width, align) * fmt->bpp;
 }
 
···
 	case V4L2_FIELD_INTERLACED_BT:
 	case V4L2_FIELD_INTERLACED:
 	case V4L2_FIELD_ALTERNATE:
+	case V4L2_FIELD_SEQ_TB:
+	case V4L2_FIELD_SEQ_BT:
 		break;
 	default:
 		pix->field = RVIN_DEFAULT_FIELD;

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

···
 };
 
 /**
+ * enum rvin_buffer_type
+ *
+ * Describes how a buffer is given to the hardware. To be able
+ * to capture SEQ_TB/BT it's needed to capture to the same vb2
+ * buffer twice so the type of buffer needs to be kept.
+ *
+ * FULL - One capture fills the whole vb2 buffer
+ * HALF_TOP - One capture fills the top half of the vb2 buffer
+ * HALF_BOTTOM - One capture fills the bottom half of the vb2 buffer
+ */
+enum rvin_buffer_type {
+	FULL,
+	HALF_TOP,
+	HALF_BOTTOM,
+};
+
+/**
  * struct rvin_video_format - Data format stored in memory
  * @fourcc:	Pixelformat
  * @bpp:	Bytes per pixel
···
 	spinlock_t qlock;
 	struct {
 		struct vb2_v4l2_buffer *buffer;
+		enum rvin_buffer_type type;
+		dma_addr_t phys;
 	} buf_hw[HW_BUFFER_NUM];
 	struct list_head buf_list;
 	unsigned int sequence;