[PATCH 5/6] v4l: Add source event change for bit-depth

From: Stanimir Varbanov <stanimir.varbanov@linaro.org>
To: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org
Cc: Vikash Garodia <vgarodia@codeaurora.org>,
	Tomasz Figa <tfiga@chromium.org>,
	Stanimir Varbanov <stanimir.varbanov@linaro.org>
Subject: [PATCH 5/6] v4l: Add source event change for bit-depth
Date: Mon,  9 Dec 2019 10:38:23 +0200	[thread overview]
Message-ID: <20191209083824.806-6-stanimir.varbanov@linaro.org> (raw)
In-Reply-To: <20191209083824.806-1-stanimir.varbanov@linaro.org>

This event indicate that the source color bit-depth is changed
during run-time. The client must get the new format and re-allocate
buffers for it. This can usually happens with video decoder (encoders)
when the bit-stream color bit-depth is changed from 8 to 10bits
or vice versa.

Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
---
 Documentation/media/uapi/v4l/vidioc-dqevent.rst | 8 +++++++-
 Documentation/media/videodev2.h.rst.exceptions  | 1 +
 include/uapi/linux/videodev2.h                  | 1 +
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/Documentation/media/uapi/v4l/vidioc-dqevent.rst b/Documentation/media/uapi/v4l/vidioc-dqevent.rst
index 42659a3d1705..fad853d440cf 100644
--- a/Documentation/media/uapi/v4l/vidioc-dqevent.rst
+++ b/Documentation/media/uapi/v4l/vidioc-dqevent.rst
@@ -402,7 +402,13 @@ call.
 	that many Video Capture devices are not able to recover from a temporary
 	loss of signal and so restarting streaming I/O is required in order for
 	the hardware to synchronize to the video signal.
-
+    * - ``V4L2_EVENT_SRC_CH_COLOR_DEPTH``
+      - 0x0002
+      - This event gets triggered when color bit-depth change is detected
+	from a video decoder. Applications will have to query the new pixel
+	format and re-negotiate the queue. In most cases the streaming must be
+	stopped and restarted (:ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>`
+	followed by :ref:`VIDIOC_STREAMON <VIDIOC_STREAMON>`).
 
 Return Value
 ============
diff --git a/Documentation/media/videodev2.h.rst.exceptions b/Documentation/media/videodev2.h.rst.exceptions
index cb6ccf91776e..209709114378 100644
--- a/Documentation/media/videodev2.h.rst.exceptions
+++ b/Documentation/media/videodev2.h.rst.exceptions
@@ -490,6 +490,7 @@ replace define V4L2_EVENT_CTRL_CH_FLAGS ctrl-changes-flags
 replace define V4L2_EVENT_CTRL_CH_RANGE ctrl-changes-flags
 
 replace define V4L2_EVENT_SRC_CH_RESOLUTION src-changes-flags
+replace define V4L2_EVENT_SRC_CH_COLOR_DEPTH src-changes-flags
 
 replace define V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ :c:type:`v4l2_event_motion_det`
 
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 04481c717fee..2a5138ac6d25 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -2307,6 +2307,7 @@ struct v4l2_event_frame_sync {
 };
 
 #define V4L2_EVENT_SRC_CH_RESOLUTION		(1 << 0)
+#define V4L2_EVENT_SRC_CH_COLOR_DEPTH		(1 << 1)
 
 struct v4l2_event_src_change {
 	__u32 changes;
-- 
2.17.1

