[PATCH v3 1/8] [media] s5p-jpeg: Call jpeg_bound_align_image after qbuf

From: Thierry Escande
Date: Tue Jun 27 2017 - 12:09:13 EST


From: Tony K Nadackal <tony.kn@xxxxxxxxxxx>

When queuing an OUTPUT buffer for decoder, s5p_jpeg_parse_hdr()
function parses the input jpeg file and takes the width and height
parameters from its header. These new width/height values will be used
for the calculation of stride. HX_JPEG Hardware needs the width and
height values aligned on a 16 bits boundary. This width/height alignment
is handled in the s5p_jpeg_s_fmt_vid_cap() function during the S_FMT
ioctl call.

But if user space calls the QBUF of OUTPUT buffer after the S_FMT of
CAPTURE buffer, these aligned values will be replaced by the values in
jpeg header. If the width/height values of jpeg are not aligned, the
decoder output will be corrupted. So in this patch we call
jpeg_bound_align_image() to align the width/height values of Capture
buffer in s5p_jpeg_buf_queue().

Signed-off-by: Tony K Nadackal <tony.kn@xxxxxxxxxxx>
Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxxxxx>
---
drivers/media/platform/s5p-jpeg/jpeg-core.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)

diff --git a/drivers/media/platform/s5p-jpeg/jpeg-core.c b/drivers/media/platform/s5p-jpeg/jpeg-core.c
index 52dc794..623508d 100644
--- a/drivers/media/platform/s5p-jpeg/jpeg-core.c
+++ b/drivers/media/platform/s5p-jpeg/jpeg-core.c
@@ -2523,6 +2523,25 @@ static void s5p_jpeg_buf_queue(struct vb2_buffer *vb)
q_data = &ctx->cap_q;
q_data->w = tmp.w;
q_data->h = tmp.h;
+
+ /*
+ * This call to jpeg_bound_align_image() takes care of width and
+ * height values alignment when user space calls the QBUF of
+ * OUTPUT buffer after the S_FMT of CAPTURE buffer.
+ * Please note that on Exynos4x12 SoCs, resigning from executing
+ * S_FMT on capture buffer for each JPEG image can result in a
+ * hardware hangup if subsampling is lower than the one of input
+ * JPEG.
+ */
+ jpeg_bound_align_image(ctx,
+ &q_data->w,
+ S5P_JPEG_MIN_WIDTH, S5P_JPEG_MAX_WIDTH,
+ q_data->fmt->h_align,
+ &q_data->h,
+ S5P_JPEG_MIN_HEIGHT, S5P_JPEG_MAX_HEIGHT,
+ q_data->fmt->v_align);
+
+ q_data->size = q_data->w * q_data->h * q_data->fmt->depth >> 3;
}

v4l2_m2m_buf_queue(ctx->fh.m2m_ctx, vbuf);
--
2.7.4