media: videodev2.h: add V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM

Add an enum_fmt format flag to specifically tag coded formats where
full bytestream parsing is supported by the device.

Some stateful decoders are capable of fully parsing a bytestream,
but others require that userspace pre-parses the bytestream into
frames or fields (see the corresponding pixelformat descriptions
for details).

If this flag is set, then this pre-parsing step is not required
(but still possible, of course).

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Alexandre Courbot <acourbot@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

3 files changed, 12 insertions, 2 deletions

diff --git a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
index 822d6730e7d2..ebc05ce74bdf 100644
--- a/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
+++ b/Documentation/media/uapi/v4l/vidioc-enum-fmt.rst
@@ -127,6 +127,14 @@ one until ``EINVAL`` is returned.
       - This format is not native to the device but emulated through
         software (usually libv4l2), where possible try to use a native
         format instead for better performance.
+    * - ``V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM``
+      - 0x0004
+      - The hardware decoder for this compressed bytestream format (aka coded
+        format) is capable of parsing a continuous bytestream. Applications do
+        not need to parse the bytestream themselves to find the boundaries
+        between frames/fields. This flag can only be used in combination with
+        the ``V4L2_FMT_FLAG_COMPRESSED`` flag, since this applies to compressed
+        formats only. This flag is valid for stateful decoders only.
 
 
 Return Value
diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
index 8e7d3492d248..a0640b6d0f68 100644
--- a/Documentation/media/videodev2.h.rst.exceptions
+++ b/Documentation/media/videodev2.h.rst.exceptions
@@ -180,6 +180,7 @@ replace define V4L2_PIX_FMT_FLAG_PREMUL_ALPHA reserved-formats
 # V4L2 format flags
 replace define V4L2_FMT_FLAG_COMPRESSED fmtdesc-flags
 replace define V4L2_FMT_FLAG_EMULATED fmtdesc-flags
+replace define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM fmtdesc-flags
 
 # V4L2 timecode types
 replace define V4L2_TC_TYPE_24FPS timecode-type
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 2427bc4d8eba..67077d52c59d 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -774,8 +774,9 @@ struct v4l2_fmtdesc {
         __u32               reserved[4];
 };
 
-#define V4L2_FMT_FLAG_COMPRESSED 0x0001
-#define V4L2_FMT_FLAG_EMULATED   0x0002
+#define V4L2_FMT_FLAG_COMPRESSED                0x0001
+#define V4L2_FMT_FLAG_EMULATED                  0x0002
+#define V4L2_FMT_FLAG_CONTINUOUS_BYTESTREAM     0x0004
 
         /* Frame Size and frame rate enumeration */
 /*