From: Kamil Debski Date: Mon, 23 Feb 2015 12:26:19 +0000 (-0300) Subject: [media] s5p-mfc: set allow_zero_bytesused flag for vb2_queue_init X-Git-Tag: firefly_0821_release~176^2~795^2~1021 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e6c9dec3e7d68c477768e2955c7f8ed78a09bfd6;p=firefly-linux-kernel-4.4.55.git [media] s5p-mfc: set allow_zero_bytesused flag for vb2_queue_init The s5p-mfc driver interprets a buffer with bytesused equal to 0 as a special case indicating end-of-stream. After vb2: fix bytesused == 0 handling (8a75ffb) patch videobuf2 modified the value of bytesused if it was 0. The allow_zero_bytesused flag was added to videobuf2 to keep backward compatibility. Signed-off-by: Kamil Debski Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc.c b/drivers/media/platform/s5p-mfc/s5p_mfc.c index 8e44a59d8ec2..9fe4d90f54a8 100644 --- a/drivers/media/platform/s5p-mfc/s5p_mfc.c +++ b/drivers/media/platform/s5p-mfc/s5p_mfc.c @@ -843,6 +843,13 @@ static int s5p_mfc_open(struct file *file) ret = -ENOENT; goto err_queue_init; } + /* One way to indicate end-of-stream for MFC is to set the + * bytesused == 0. However by default videobuf2 handles bytesused + * equal to 0 as a special case and changes its value to the size + * of the buffer. Set the allow_zero_bytesused flag so that videobuf2 + * will keep the value of bytesused intact. + */ + q->allow_zero_bytesused = 1; q->mem_ops = &vb2_dma_contig_memops; q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY; ret = vb2_queue_init(q);