summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Documentation/DocBook/media/v4l/io.xml36
-rw-r--r--drivers/media/v4l2-core/videobuf2-core.c4
-rw-r--r--include/media/videobuf2-core.h2
-rw-r--r--include/uapi/linux/videodev2.h4
4 files changed, 39 insertions, 7 deletions
diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml
index 5a2e97bbc6bf..1e7ea3c2e2ad 100644
--- a/Documentation/DocBook/media/v4l/io.xml
+++ b/Documentation/DocBook/media/v4l/io.xml
@@ -653,12 +653,6 @@ plane, are stored in struct <structname>v4l2_plane</structname> instead.
In that case, struct <structname>v4l2_buffer</structname> contains an array of
plane structures.</para>
- <para>For timestamp types that are sampled from the system clock
-(V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC) it is guaranteed that the timestamp is
-taken after the complete frame has been received (or transmitted in
-case of video output devices). For other kinds of
-timestamps this may vary depending on the driver.</para>
-
<table frame="none" pgwide="1" id="v4l2-buffer">
<title>struct <structname>v4l2_buffer</structname></title>
<tgroup cols="4">
@@ -1125,6 +1119,36 @@ in which case caches have not been used.</entry>
<entry>The CAPTURE buffer timestamp has been taken from the
corresponding OUTPUT buffer. This flag applies only to mem2mem devices.</entry>
</row>
+ <row>
+ <entry><constant>V4L2_BUF_FLAG_TSTAMP_SRC_MASK</constant></entry>
+ <entry>0x00070000</entry>
+ <entry>Mask for timestamp sources below. The timestamp source
+ defines the point of time the timestamp is taken in relation to
+ the frame. Logical 'and' operation between the
+ <structfield>flags</structfield> field and
+ <constant>V4L2_BUF_FLAG_TSTAMP_SRC_MASK</constant> produces the
+ value of the timestamp source.</entry>
+ </row>
+ <row>
+ <entry><constant>V4L2_BUF_FLAG_TSTAMP_SRC_EOF</constant></entry>
+ <entry>0x00000000</entry>
+ <entry>End Of Frame. The buffer timestamp has been taken
+ when the last pixel of the frame has been received or the
+ last pixel of the frame has been transmitted. In practice,
+ software generated timestamps will typically be read from
+ the clock a small amount of time after the last pixel has
+ been received or transmitten, depending on the system and
+ other activity in it.</entry>
+ </row>
+ <row>
+ <entry><constant>V4L2_BUF_FLAG_TSTAMP_SRC_SOE</constant></entry>
+ <entry>0x00010000</entry>
+ <entry>Start Of Exposure. The buffer timestamp has been
+ taken when the exposure of the frame has begun. This is
+ only valid for the
+ <constant>V4L2_BUF_TYPE_VIDEO_CAPTURE</constant> buffer
+ type.</entry>
+ </row>
</tbody>
</tgroup>
</table>
diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
index 521350a74c46..42a856813d06 100644
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -2227,7 +2227,9 @@ int vb2_queue_init(struct vb2_queue *q)
WARN_ON(!q->io_modes) ||
WARN_ON(!q->ops->queue_setup) ||
WARN_ON(!q->ops->buf_queue) ||
- WARN_ON(q->timestamp_flags & ~V4L2_BUF_FLAG_TIMESTAMP_MASK))
+ WARN_ON(q->timestamp_flags &
+ ~(V4L2_BUF_FLAG_TIMESTAMP_MASK |
+ V4L2_BUF_FLAG_TSTAMP_SRC_MASK)))
return -EINVAL;
/* Warn that the driver should choose an appropriate timestamp type */
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index 3770be6e972d..bf6859ee46c3 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -312,6 +312,8 @@ struct v4l2_fh;
* @buf_struct_size: size of the driver-specific buffer structure;
* "0" indicates the driver doesn't want to use a custom buffer
* structure type, so sizeof(struct vb2_buffer) will is used
+ * @timestamp_flags: Timestamp flags; V4L2_BUF_FLAGS_TIMESTAMP_* and
+ * V4L2_BUF_FLAGS_TSTAMP_SRC_*
* @gfp_flags: additional gfp flags used when allocating the buffers.
* Typically this is 0, but it may be e.g. GFP_DMA or __GFP_DMA32
* to force the buffer allocation to a specific memory zone.
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index cb838765dd40..17acba8c7f9f 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -700,6 +700,10 @@ struct v4l2_buffer {
#define V4L2_BUF_FLAG_TIMESTAMP_UNKNOWN 0x00000000
#define V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC 0x00002000
#define V4L2_BUF_FLAG_TIMESTAMP_COPY 0x00004000
+/* Timestamp sources. */
+#define V4L2_BUF_FLAG_TSTAMP_SRC_MASK 0x00070000
+#define V4L2_BUF_FLAG_TSTAMP_SRC_EOF 0x00000000
+#define V4L2_BUF_FLAG_TSTAMP_SRC_SOE 0x00010000
/**
* struct v4l2_exportbuffer - export of video buffer as DMABUF file descriptor