[RFC,v5, 3/5] media: videodev2.h: Add new boottime timestamp type

[Jungo Lin <jungo.lin@mediatek.com>]

For Camera AR(Augmented Reality) application requires camera timestamps
to be reported with CLOCK_BOOTTIME to sync timestamp with other sensor
sources.

The boottime timestamp is identical to monotonic timestamp,
except it also includes any time that the system is suspended.

Signed-off-by: Jungo Lin <jungo.lin@mediatek.com>
---
 Documentation/media/uapi/v4l/buffer.rst | 11 ++++++++++-
 include/uapi/linux/videodev2.h          |  2 ++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/Documentation/media/uapi/v4l/buffer.rst b/Documentation/media/uapi/v4l/buffer.rst
index 1cbd9cde57f3..9e636f4118f5 100644
--- a/Documentation/media/uapi/v4l/buffer.rst
+++ b/Documentation/media/uapi/v4l/buffer.rst
@@ -649,13 +649,22 @@ Buffer Flags
       - 0x00002000
       - The buffer timestamp has been taken from the ``CLOCK_MONOTONIC``
 	clock. To access the same clock outside V4L2, use
-	:c:func:`clock_gettime`.
+	:c:func:`clock_gettime` using clock IDs ``CLOCK_MONOTONIC``.
     * .. _`V4L2-BUF-FLAG-TIMESTAMP-COPY`:
 
       - ``V4L2_BUF_FLAG_TIMESTAMP_COPY``
       - 0x00004000
       - The CAPTURE buffer timestamp has been taken from the corresponding
 	OUTPUT buffer. This flag applies only to mem2mem devices.
+    * .. _`V4L2_BUF_FLAG_TIMESTAMP_BOOTIME`:
+
+      - ``V4L2_BUF_FLAG_TIMESTAMP_BOOTIME``
+      - 0x00008000
+      - The buffer timestamp has been taken from the ``CLOCK_BOOTTIME``
+	clock. To access the same clock outside V4L2, use
+	:c:func:`clock_gettime` using clock IDs ``CLOCK_BOOTTIME``.
+	Identical to CLOCK_MONOTONIC, except it also includes any time that
+	the system is suspended.
     * .. _`V4L2-BUF-FLAG-TSTAMP-SRC-MASK`:
 
       - ``V4L2_BUF_FLAG_TSTAMP_SRC_MASK``
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 9d9705ceda76..a4fd271348e7 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -1043,6 +1043,8 @@ static inline __u64 v4l2_timeval_to_ns(const struct timeval *tv)
 #define V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN		0x00000000
 #define V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC	0x00002000
 #define V4L2_BUF_FLAG_TIMESTAMP_COPY		0x00004000
+#define V4L2_BUF_FLAG_TIMESTAMP_BOOTIME		0x00008000
+
 /* Timestamp sources. */
 #define V4L2_BUF_FLAG_TSTAMP_SRC_MASK		0x00070000
 #define V4L2_BUF_FLAG_TSTAMP_SRC_EOF		0x00000000
-- 
2.18.0