[PATCH AUTOSEL 4.19 097/158] media: coda: fix mpeg2 sequence number handling

From: Sasha Levin
Date: Mon Jul 15 2019 - 10:56:00 EST


From: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>

[ Upstream commit 56d159a4ec6d8da7313aac6fcbb95d8fffe689ba ]

Sequence number handling assumed that the BIT processor frame number
starts counting at 1, but this is not true for the MPEG-2 decoder,
which starts at 0. Fix the sequence counter offset detection to handle
this.

Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/media/platform/coda/coda-bit.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/media/platform/coda/coda-bit.c b/drivers/media/platform/coda/coda-bit.c
index a3cfefdbee12..25ef0c928a81 100644
--- a/drivers/media/platform/coda/coda-bit.c
+++ b/drivers/media/platform/coda/coda-bit.c
@@ -1728,6 +1728,7 @@ static int __coda_start_decoding(struct coda_ctx *ctx)
v4l2_err(&dev->v4l2_dev, "CODA_COMMAND_SEQ_INIT timeout\n");
return ret;
}
+ ctx->sequence_offset = ~0U;
ctx->initialized = 1;

/* Update kfifo out pointer from coda bitstream read pointer */
@@ -2147,7 +2148,9 @@ static void coda_finish_decode(struct coda_ctx *ctx)
v4l2_err(&dev->v4l2_dev,
"decoded frame index out of range: %d\n", decoded_idx);
} else {
- val = coda_read(dev, CODA_RET_DEC_PIC_FRAME_NUM) - 1;
+ val = coda_read(dev, CODA_RET_DEC_PIC_FRAME_NUM);
+ if (ctx->sequence_offset == -1)
+ ctx->sequence_offset = val;
val -= ctx->sequence_offset;
spin_lock_irqsave(&ctx->buffer_meta_lock, flags);
if (!list_empty(&ctx->buffer_meta_list)) {
--
2.20.1