On Tue, 2025-12-16 at 16:22 -0500, Nicolas Dufresne wrote:

Hi,

Le mardi 02 décembre 2025 à 17:47 +0800, Kyrie Wu a écrit :

quoted

For memory alloc operation of jpeg dst buffer: the mallocing
memory function interface use vb2_buffer as the base addr.
If structure mtk_jpeg_src_buf wants to be allocated to memory,
it needs to be placed vb2_v4l2_buffer at the starting position,
because structure vb2_buffer is at the starting position of
vb2_v4l2_buffer, and the allocated size is set to the size of
structure mtk_jpeg_src_buf, so as to ensure that structures
mtk_jpeg_src_buf, vb2_v4l2_buffer and vb2_buffer can all be
allocated memory.

Please correct the wording, "mallocing" is not a word, addr ->
address. I tend
to do the same, but refrain from giving the code a personality, the
vb2_buffer
have no will. This is overall complicated way to simply say:

	Fix the size of the allocated mtk_jpeg_src_buf structure.

quoted

Fixes: 5fb1c2361e56 ("mtk-jpegenc: add jpeg encode worker
interface")

Drop the blank line.

quoted

Signed-off-by: Kyrie Wu <redacted>
---
 drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c | 2 +-
 drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c

b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
index 0cf3dc5407e4..bd0afc93d491 100644

--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.c

@@ -1099,7 +1099,7 @@ static int mtk_jpeg_queue_init(void *priv,

struct vb2_queue *src_vq,
 	dst_vq->type = V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
 	dst_vq->io_modes = VB2_DMABUF | VB2_MMAP;
 	dst_vq->drv_priv = ctx;
-	dst_vq->buf_struct_size = sizeof(struct v4l2_m2m_buffer);
+	dst_vq->buf_struct_size = sizeof(struct mtk_jpeg_src_buf);
 	dst_vq->ops = jpeg->variant->qops;
 	dst_vq->mem_ops = &vb2_dma_contig_memops;
 	dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;

diff --git a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.h

b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.h
index 6be5cf30dea1..148fd41759b7 100644

--- a/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.h
+++ b/drivers/media/platform/mediatek/jpeg/mtk_jpeg_core.h

@@ -85,10 +85,10 @@ struct mtk_jpeg_variant {
 };
 
 struct mtk_jpeg_src_buf {
-	u32 frame_num;
 	struct vb2_v4l2_buffer b;
 	struct list_head list;
 	u32 bs_size;
+	u32 frame_num;

I like the change, but this shouldn't be an issue if you use
container_of, which
is safer then a plain cast. Please review the code and make sure to
use it. It
may be confusing to include a cosmetic change in a fixes.

Nicolas

Dear Nicolas,

The driver requests memory space for mtk_jpeg_src_buf in the
function of mtk_jpeg_queue_init,
and it used struct vb2_v4l2_buffer b as the starting base address,
the parameter,frame_num, will not get a memory if we keep the old
structure. And a unknown memory would be get if we used container_of
to get the starting address of mtk_jpeg_src_buf.

Thanks.

Regards,
Kyrie.

quoted

 	struct mtk_jpeg_dec_param dec_param;
 
 	struct mtk_jpeg_ctx *curr_ctx;