[PATCH v16 02/12] media: mediatek: jpeg: fix jpeg buffer payload size setting

[Kyrie Wu <kyrie.wu@mediatek.com>]

For multi-core jpegdec, if one core gets resolution change event,
the payload size, representing the size of Y/C data, needs to change.
But others are decoding at the same time and it can not be changed
immediately, which results in the payload size not matching the real
buffer length.
The payload size must be less than the real buffer length to avoid
warning logs.

Fixes: 0fa49df4222f ("media: mtk-jpegdec: support jpegdec multi-hardware")
Signed-off-by: Kyrie Wu <kyrie.wu@mediatek.com>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
---
 .../platform/mediatek/jpeg/mtk_jpeg_core.c    | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 41c4cf8dc..34135706a 100644
--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
@@ -702,6 +702,7 @@ static int mtk_jpeg_buf_prepare(struct vb2_buffer *vb)
 	struct mtk_jpeg_ctx *ctx = vb2_get_drv_priv(vb->vb2_queue);
 	struct mtk_jpeg_q_data *q_data = NULL;
 	struct v4l2_plane_pix_format plane_fmt = {};
+	size_t max_size;
 	int i;
 
 	q_data = mtk_jpeg_get_q_data(ctx, vb->vb2_queue->type);
@@ -710,12 +711,20 @@ static int mtk_jpeg_buf_prepare(struct vb2_buffer *vb)
 
 	for (i = 0; i < q_data->fmt->colplanes; i++) {
 		plane_fmt = q_data->pix_mp.plane_fmt[i];
+		max_size = plane_fmt.sizeimage;
+
 		if (ctx->enable_exif &&
-		    q_data->fmt->fourcc == V4L2_PIX_FMT_JPEG)
-			vb2_set_plane_payload(vb, i, plane_fmt.sizeimage +
-					      MTK_JPEG_MAX_EXIF_SIZE);
-		else
-			vb2_set_plane_payload(vb, i,  plane_fmt.sizeimage);
+			q_data->fmt->fourcc == V4L2_PIX_FMT_JPEG) {
+			max_size += MTK_JPEG_MAX_EXIF_SIZE;
+
+			vb2_set_plane_payload(vb, i,
+					      MIN(vb->planes[i].length,
+						  max_size));
+		} else {
+			vb2_set_plane_payload(vb, i,
+					      MIN(plane_fmt.sizeimage,
+						  vb->planes[i].length));
+		}
 	}
 
 	return 0;
-- 
2.51.0.windows.2