[PATCH v6 06/12] media: imx-csi: Double crop height for alternate fields at sink

[Steve Longerbeam]

If the incoming sink field type is alternate, the reset crop height
and crop height bounds must be set to twice the incoming height,
because in alternate field mode, upstream will report only the
lines for a single field, and the CSI captures the whole frame.

Signed-off-by: Steve Longerbeam <slongerbeam@xxxxxxxxx>
Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
---
 drivers/staging/media/imx/imx-media-csi.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index b276672cae1d..c40c3262038e 100644
--- a/drivers/staging/media/imx/imx-media-csi.c
+++ b/drivers/staging/media/imx/imx-media-csi.c
@@ -1142,6 +1142,8 @@ static void csi_try_crop(struct csi_priv *priv,
 			 struct v4l2_mbus_framefmt *infmt,
 			 struct v4l2_fwnode_endpoint *upstream_ep)
 {
+	u32 in_height;
+
 	crop->width = min_t(__u32, infmt->width, crop->width);
 	if (crop->left + crop->width > infmt->width)
 		crop->left = infmt->width - crop->width;
@@ -1149,6 +1151,10 @@ static void csi_try_crop(struct csi_priv *priv,
 	crop->left &= ~0x3;
 	crop->width &= ~0x7;
 
+	in_height = infmt->height;
+	if (infmt->field == V4L2_FIELD_ALTERNATE)
+		in_height *= 2;
+
 	/*
 	 * FIXME: not sure why yet, but on interlaced bt.656,
 	 * changing the vertical cropping causes loss of vertical
@@ -1158,12 +1164,12 @@ static void csi_try_crop(struct csi_priv *priv,
 	if (upstream_ep->bus_type == V4L2_MBUS_BT656 &&
 	    (V4L2_FIELD_HAS_BOTH(infmt->field) ||
 	     infmt->field == V4L2_FIELD_ALTERNATE)) {
-		crop->height = infmt->height;
-		crop->top = (infmt->height == 480) ? 2 : 0;
+		crop->height = in_height;
+		crop->top = (in_height == 480) ? 2 : 0;
 	} else {
-		crop->height = min_t(__u32, infmt->height, crop->height);
-		if (crop->top + crop->height > infmt->height)
-			crop->top = infmt->height - crop->height;
+		crop->height = min_t(__u32, in_height, crop->height);
+		if (crop->top + crop->height > in_height)
+			crop->top = in_height - crop->height;
 	}
 }
 
@@ -1403,6 +1409,8 @@ static void csi_try_fmt(struct csi_priv *priv,
 		crop->top = 0;
 		crop->width = sdformat->format.width;
 		crop->height = sdformat->format.height;
+		if (sdformat->format.field == V4L2_FIELD_ALTERNATE)
+			crop->height *= 2;
 		csi_try_crop(priv, crop, cfg, &sdformat->format, upstream_ep);
 		compose->left = 0;
 		compose->top = 0;
@@ -1530,6 +1538,8 @@ static int csi_get_selection(struct v4l2_subdev *sd,
 		sel->r.top = 0;
 		sel->r.width = infmt->width;
 		sel->r.height = infmt->height;
+		if (infmt->field == V4L2_FIELD_ALTERNATE)
+			sel->r.height *= 2;
 		break;
 	case V4L2_SEL_TGT_CROP:
 		sel->r = *crop;
-- 
2.17.1