Merge tag 'br-v6.2e' of git://linuxtv.org/hverkuil/media_tree into media_stage

Tag branch

* tag 'br-v6.2e' of git://linuxtv.org/hverkuil/media_tree: (29 commits)
  media: davinci/vpbe: Fix a typo ("defualt_mode")
  media: sun6i-csi: Remove unnecessary print function dev_err()
  media: Documentation: Drop deprecated bytesused == 0
  media: platform: exynos4-is: fix return value check in fimc_md_probe()
  media: dvb-core: remove variable n, turn for-loop to while-loop
  media: vivid: fix compose size exceed boundary
  media: rkisp1: make const arrays ae_wnd_num and hist_wnd_num static
  media: dvb-core: Fix UAF due to refcount races at releasing
  media: rkvdec: Add required padding
  media: aspeed: Extend debug message
  media: aspeed: Support aspeed mode to reduce compressed data
  media: Documentation: aspeed-video: Add user documentation for the aspeed-video driver
  media: v4l2-ctrls: Reserve controls for ASPEED
  media: v4l: Add definition for the Aspeed JPEG format
  staging: media: tegra-video: fix device_node use after free
  staging: media: tegra-video: fix chan->mipi value on error
  media: cedrus: initialize controls a bit later
  media: cedrus: prefer untiled capture format
  media: cedrus: Remove cedrus_codec enum
  media: cedrus: set codec ops immediately
  ...

4 files changed, 86 insertions, 8 deletions

diff --git a/Documentation/userspace-api/media/drivers/aspeed-video.rst b/Documentation/userspace-api/media/drivers/aspeed-video.rst
new file mode 100644
index 000000000000..1b0cb1e3eba8
--- /dev/null
+++ b/Documentation/userspace-api/media/drivers/aspeed-video.rst
@@ -0,0 +1,65 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: <isonum.txt>
+
+ASPEED video driver
+===================
+
+ASPEED Video Engine found on AST2400/2500/2600 SoC supports high performance
+video compressions with a wide range of video quality and compression ratio
+options. The adopted compressing algorithm is a modified JPEG algorithm.
+
+There are 2 types of compressions in this IP.
+
+* JPEG JFIF standard mode: for single frame and management compression
+* ASPEED proprietary mode: for multi-frame and differential compression.
+  Support 2-pass (high quality) video compression scheme (Patent pending by
+  ASPEED). Provide visually lossless video compression quality or to reduce
+  the network average loading under intranet KVM applications.
+
+VIDIOC_S_FMT can be used to choose which format you want. V4L2_PIX_FMT_JPEG
+stands for JPEG JFIF standard mode; V4L2_PIX_FMT_AJPG stands for ASPEED
+proprietary mode.
+
+More details on the ASPEED video hardware operations can be found in
+*chapter 6.2.16 KVM Video Driver* of SDK_User_Guide which available on
+AspeedTech-BMC/openbmc/releases.
+
+The ASPEED video driver implements the following driver-specific control:
+
+``V4L2_CID_ASPEED_HQ_MODE``
+---------------------------
+    Enable/Disable ASPEED's High quality mode. This is a private control
+    that can be used to enable high quality for aspeed proprietary mode.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``(0)``
+      - ASPEED HQ mode is disabled.
+    * - ``(1)``
+      - ASPEED HQ mode is enabled.
+
+``V4L2_CID_ASPEED_HQ_JPEG_QUALITY``
+-----------------------------------
+    Define the quality of ASPEED's High quality mode. This is a private control
+    that can be used to decide compression quality if High quality mode enabled
+    . Higher the value, better the quality and bigger the size.
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       1 4
+
+    * - ``(1)``
+      - minimum
+    * - ``(12)``
+      - maximum
+    * - ``(1)``
+      - step
+    * - ``(1)``
+      - default
+
+**Copyright** |copy| 2022 ASPEED Technology Inc.
diff --git a/Documentation/userspace-api/media/drivers/index.rst b/Documentation/userspace-api/media/drivers/index.rst
index 32f82aed47d9..46a494e00b72 100644
--- a/Documentation/userspace-api/media/drivers/index.rst
+++ b/Documentation/userspace-api/media/drivers/index.rst
@@ -31,6 +31,7 @@ For more details see the file COPYING in the source distribution of Linux.
 	:maxdepth: 5
 	:numbered:
 
+	aspeed-video
 	ccs
 	cx2341x-uapi
 	dw100
diff --git a/Documentation/userspace-api/media/v4l/buffer.rst b/Documentation/userspace-api/media/v4l/buffer.rst
index 4638ec64db00..04dec3e570ed 100644
--- a/Documentation/userspace-api/media/v4l/buffer.rst
+++ b/Documentation/userspace-api/media/v4l/buffer.rst
@@ -187,10 +187,8 @@ struct v4l2_buffer
 	on the negotiated data format and may change with each buffer for
 	compressed variable size data like JPEG images. Drivers must set
 	this field when ``type`` refers to a capture stream, applications
-	when it refers to an output stream. If the application sets this
-	to 0 for an output stream, then ``bytesused`` will be set to the
-	size of the buffer (see the ``length`` field of this struct) by
-	the driver. For multiplanar formats this field is ignored and the
+	when it refers to an output stream. For multiplanar formats this field
+        is ignored and the
 	``planes`` pointer is used instead.
     * - __u32
       - ``flags``
@@ -327,10 +325,7 @@ struct v4l2_plane
       - ``bytesused``
       - The number of bytes occupied by data in the plane (its payload).
 	Drivers must set this field when ``type`` refers to a capture
-	stream, applications when it refers to an output stream. If the
-	application sets this to 0 for an output stream, then
-	``bytesused`` will be set to the size of the plane (see the
-	``length`` field of this struct) by the driver.
+	stream, applications when it refers to an output stream.
 
 	.. note::
 
diff --git a/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst b/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst
index 0ff68cd8cf62..73cd99828010 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-reserved.rst
@@ -258,6 +258,23 @@ please make a proposal on the linux-media mailing list.
         and it is used by various multimedia hardware blocks like GPU, display
         controllers, ISP and video accelerators.
         It contains four planes for progressive video.
+    * .. _V4L2-PIX-FMT-AJPG:
+
+      - ``V4L2_PIX_FMT_AJPG``
+      - 'AJPG'
+      - ASPEED JPEG format used by the aspeed-video driver on Aspeed platforms,
+        which is generally adapted for remote KVM.
+        On each frame compression, I will compare the new frame with previous
+        one to decide which macroblock's data is changed, and only the changed
+        macroblocks will be compressed.
+
+        The implementation is based on AST2600 A3 datasheet, revision 0.9, which
+        is not publicly available. Or you can reference Video stream data format
+        – ASPEED mode compression of SDK_User_Guide which available on
+        AspeedTech-BMC/openbmc/releases.
+
+        Decoder's implementation can be found here,
+        `aspeed_codec <https://github.com/AspeedTech-BMC/aspeed_codec/>`__
 .. raw:: latex
 
     \normalsize