Commit Graph

177 Commits

Author SHA1 Message Date
Stanimir Varbanov
1ad0de78e7 media: v4l: Add HDR10 static metadata controls
Introduce Content light level and Mastering display colour
volume Colorimetry compound controls with relevant payload
structures and validation.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-04-06 14:56:00 +02:00
Mirela Rabulea
0376a51fbe media: v4l: Add packed YUV444 24bpp pixel format
The added format is V4L2_PIX_FMT_YUV24, this is a packed
YUV 4:4:4 format, with 8 bits for each component, 24 bits
per sample.

This format is used by the i.MX 8QuadMax and i.MX 8DualXPlus/8QuadXPlus
JPEG encoder/decoder.

Signed-off-by: Mirela Rabulea <mirela.rabulea@nxp.com>
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-03-22 10:34:16 +01:00
Hans Verkuil
f12b81e47f media: core headers: fix kernel-doc warnings
This patch fixes the following kernel-doc warnings:

include/uapi/linux/videodev2.h:996: warning: Function parameter or member 'm' not described in 'v4l2_plane'
include/uapi/linux/videodev2.h:996: warning: Function parameter or member 'reserved' not described in 'v4l2_plane'
include/uapi/linux/videodev2.h:1057: warning: Function parameter or member 'm' not described in 'v4l2_buffer'
include/uapi/linux/videodev2.h:1057: warning: Function parameter or member 'reserved2' not described in 'v4l2_buffer'
include/uapi/linux/videodev2.h:1057: warning: Function parameter or member 'reserved' not described in 'v4l2_buffer'
include/uapi/linux/videodev2.h:1068: warning: Function parameter or member 'tv' not described in 'v4l2_timeval_to_ns'
include/uapi/linux/videodev2.h:1068: warning: Excess function parameter 'ts' description in 'v4l2_timeval_to_ns'
include/uapi/linux/videodev2.h:1138: warning: Function parameter or member 'reserved' not described in 'v4l2_exportbuffer'
include/uapi/linux/videodev2.h:2237: warning: Function parameter or member 'reserved' not described in 'v4l2_plane_pix_format'
include/uapi/linux/videodev2.h:2270: warning: Function parameter or member 'hsv_enc' not described in 'v4l2_pix_format_mplane'
include/uapi/linux/videodev2.h:2270: warning: Function parameter or member 'reserved' not described in 'v4l2_pix_format_mplane'
include/uapi/linux/videodev2.h:2281: warning: Function parameter or member 'reserved' not described in 'v4l2_sdr_format'
include/uapi/linux/videodev2.h:2315: warning: Function parameter or member 'fmt' not described in 'v4l2_format'

include/uapi/linux/v4l2-subdev.h:53: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_format'
include/uapi/linux/v4l2-subdev.h:66: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_crop'
include/uapi/linux/v4l2-subdev.h:89: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_mbus_code_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'min_width' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'max_width' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'min_height' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'max_height' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:108: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_frame_size_enum'
include/uapi/linux/v4l2-subdev.h:119: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_frame_interval'
include/uapi/linux/v4l2-subdev.h:140: warning: Function parameter or member 'reserved' not described in 'v4l2_subdev_frame_interval_enum'

include/uapi/linux/cec.h:406: warning: Function parameter or member 'raw' not described in 'cec_connector_info'
include/uapi/linux/cec.h:470: warning: Function parameter or member 'flags' not described in 'cec_event'

include/media/v4l2-h264.h:82: warning: Function parameter or member 'reflist' not described in 'v4l2_h264_build_p_ref_list'
include/media/v4l2-h264.h:82: warning: expecting prototype for v4l2_h264_build_b_ref_lists(). Prototype was for v4l2_h264_build_p_ref_list()
instead

include/media/cec.h:50: warning: Function parameter or member 'lock' not described in 'cec_devnode'

include/media/v4l2-jpeg.h:122: warning: Function parameter or member 'num_dht' not described in 'v4l2_jpeg_header'
include/media/v4l2-jpeg.h:122: warning: Function parameter or member 'num_dqt' not described in 'v4l2_jpeg_header'

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-03-22 10:22:22 +01:00
Ezequiel Garcia
363240ce1c media: uapi: move VP8 stateless controls out of staging
Until now, the VP8 V4L2 API was not exported as a public API,
and only defined in a private media header (media/vp8-ctrls.h).

The reason for this was a concern about the API not complete
and ready to support VP8 decoding hardware accelerators.

After reviewing the VP8 specification in detail, and now
that the API is able to support Cedrus and Hantro G1,
we can consider this ready.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-03-22 09:52:12 +01:00
Ezequiel Garcia
e74b504a87 media: uapi: Move the VP8 stateless control type out of staging
Move the VP8 stateless control types out of staging,
and re-number it to avoid any confusion.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-03-22 09:50:57 +01:00
Ezequiel Garcia
1fb03333eb media: uapi: Move parsed VP8 pixel format out of staging
Since we are ready to stabilize the VP8 stateless API,
move the parsed VP8 pixel format.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2021-03-22 09:50:38 +01:00
Laurent Pinchart
e9a66489c3 media: doc: pixfmt-rgb: Clarify naming scheme for RGB formats
The naming scheme for the RGB pixel formats has been developed
organically, and isn't consistent between formats using less than 8 bits
per pixels (mostly stored in 1 or 2 bytes per pixel, except for RGB666
that uses 4 bytes per pixel) and formats with 8 bits per pixel (stored
in 3 or 4 bytes). For the latter category, the names use a components
order convention that is the opposite of the first category, and the
opposite of DRM pixel formats. This has led to lots of confusion in the
past, and would really benefit from being explained more precisely. Do
so, which also prepares for the addition of additional RGB pixels
formats.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-07 14:02:37 +01:00
Laurent Pinchart
473dbed54f media: videodev2.h: Move HM12 format to YUV semi-planar section
V4L2_PIX_FMT_HM12 is a YUV semi-planar macro-block format. Move it from
the packed YUV formats section where it was misplaced to the YUV
semi-planar formats section.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-07 13:59:24 +01:00
Laurent Pinchart
0a078e0d8e media: videodev2.h: Move HI240 format to vendor-specific section
V4L2_PIX_FMT_HI240 is a 8-bit dithered RGB format specific to BTTV. Move
it from the packed YUV formats section where it was misplaced to the
vendor-specific formats section.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-07 13:58:16 +01:00
Laurent Pinchart
3771c031d6 media: videodev2.h: Remove unneeded comment about 4CC value
The V4L2_PIX_FMT_BGRA444 format has a comment that explains why its 4CC
value is GA12. This explains the development history and isn't of much
interest to readers, it should have been part of a commit message
instead. Drop the comment, anyone interested in history can turn to git.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-07 13:57:36 +01:00
Hans Verkuil
206bc0f6fb media: vicodec: mark the stateless FWHT API as stable
The FWHT stateless 'uAPI' was staging and marked explicitly in the
V4L2 specification that it will change and is unstable.
Note that these control IDs were never exported as a public API,
they were only defined in kernel-local headers (fwht-ctrls.h).

Now, the FWHT stateless controls is ready to be part
of the stable uAPI.

While not too late:

- Rename V4L2_CID_MPEG_VIDEO_FWHT_PARAMS to V4L2_CID_STATELESS_FWHT_PARAMS.

- Move the contents of fwht-ctrls.h to v4l2-controls.h.

- Move the public parts of drivers/media/test-drivers/vicodec/codec-fwht.h
  to v4l2-controls.h.

- Add V4L2_CTRL_TYPE_FWHT_PARAMS control initialization and validation.

- Add p_fwht_params to struct v4l2_ext_control.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-03 12:27:33 +01:00
Ezequiel Garcia
46a309d275 media: uapi: move H264 stateless controls out of staging
The H.264 stateless 'uAPI' was staging and marked explicitly in the
V4L2 specification that it will change and is unstable.

Note that these control IDs were never exported as a public API,
they were only defined in kernel-local headers (h264-ctrls.h).

Now, the H264 stateless controls is ready to be part
of the stable uAPI.

While not too late, let's rename them and re-number their
control IDs, moving them to the newly created stateless
control class, and updating all the drivers accordingly.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Tested-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-03 12:27:33 +01:00
Ezequiel Garcia
a7ead39700 media: uapi: Move the H264 stateless control types out of staging
Move the H264 stateless control types out of staging,
and re-number them to avoid any confusion.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Tested-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-03 12:27:33 +01:00
Ezequiel Garcia
95e95ebe91 media: uapi: Move parsed H264 pixel format out of staging
Since we are ready to stabilize the H264 stateless API,
start by first moving the parsed H264 pixel format.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Tested-by: Jernej Skrabec <jernej.skrabec@siol.net>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-12-03 12:27:33 +01:00
Shunqian Zheng
df22026aeb media: videodev2.h, v4l2-ioctl: add rkisp1 meta buffer format
Add the Rockchip ISP1 specific processing parameter format
V4L2_META_FMT_RK_ISP1_PARAMS and metadata format
V4L2_META_FMT_RK_ISP1_STAT_3A for 3A.

Signed-off-by: Shunqian Zheng <zhengsq@rock-chips.com>
Signed-off-by: Jacob Chen <jacob2.chen@rock-chips.com>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-11-17 06:59:56 +01:00
Hans Verkuil
e7531d5625 media: Fix V4L2_COLORSPACE_470_SYSTEM_BG description
The description of the V4L2_COLORSPACE_470_SYSTEM_BG stated that it was
superseded by SMPTE 170M. That is incorrect. The probably root cause of
this is that the HDMI standard does not support this colorspace and,
unless otherwise signaled, will fall back to SMPTE 170M for SDTV.

However, EBU Tech. 3321 states that sources should signal Rec. 709 as the
colorimetry when using HDMI since the difference between Rec. 709 and
Tech. 3213 are negligible.

Update the text accordingly.

Also drop a spurious " at the end of the Tech 3213 title in the
bibliography.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-11-16 10:31:07 +01:00
Arnd Bergmann
3f65c6f67e media: v4l2: allocate v4l2_clip objects early
The v4l2_format based ioctls can have an indirect pointer to an array
of v4l2_clip structures for overlay mode, depending on the 'type' member.
There are only five drivers that use the overlay mode and copy the
data through the __user pointer.

Change the five drivers to use memcpy() instead, and copy the data
in common code using the check_array_args() helpers. This allows
for a subsequent patch that use the same mechanism for compat
ioctl handlers.

Note that there is another pointer for a 'bitmap' that is only
used in the 'vivid' driver and nowhere else. There is no easy
way to use the same trick without adding complexity to the
common code, so this remains a __user pointer.

[hverkuil: fix: CHECK: spaces preferred around that '*' (ctx:VxV)]
[hverkuil: fix: CHECK: Alignment should match open parenthesis]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-11-16 10:31:06 +01:00
Mauro Carvalho Chehab
463c43fcd9 Merge tag 'v5.9-rc7' into patchwork
Linux 5.9-rc7

* tag 'v5.9-rc7': (683 commits)
  Linux 5.9-rc7
  mm/thp: Split huge pmds/puds if they're pinned when fork()
  mm: Do early cow for pinned pages during fork() for ptes
  mm/fork: Pass new vma pointer into copy_page_range()
  mm: Introduce mm_struct.has_pinned
  mm: validate pmd after splitting
  mm: don't rely on system state to detect hot-plug operations
  mm: replace memmap_context by meminit_context
  arch/x86/lib/usercopy_64.c: fix __copy_user_flushcache() cache writeback
  lib/memregion.c: include memregion.h
  lib/string.c: implement stpcpy
  mm/migrate: correct thp migration stats
  mm/gup: fix gup_fast with dynamic page table folding
  mm: memcontrol: fix missing suffix of workingset_restore
  mm, THP, swap: fix allocating cluster for swapfile by mistake
  mm: slab: fix potential double free in ___cache_free
  Documentation/llvm: Fix clang target examples
  io_uring: ensure async buffered read-retry is setup properly
  KVM: SVM: Add a dedicated INVD intercept routine
  io_uring: don't unconditionally set plug->nowait = true
  ...
2020-10-04 12:19:12 +02:00
Dafna Hirschfeld
b38c73ca1c media: v4l2: add support for colorspace conversion API (CSC) for video capture
For video capture it is the driver that reports the colorspace,
transfer function, Y'CbCr/HSV encoding and quantization range
used by the video, and there is no way to request something
different, even though many HDTV receivers have some sort of
colorspace conversion capabilities.

For output video this feature already exists since the application
specifies this information for the video format it will send out, and
the transmitter will enable any available CSC if a format conversion has
to be performed in order to match the capabilities of the sink.

For video capture we propose adding new v4l2_pix_format flag:
V4L2_PIX_FMT_FLAG_SET_CSC. The flag is set by the application,
the driver will interpret the colorspace, xfer_func, ycbcr_enc/hsv_enc
and quantization fields as the requested colorspace information and will
attempt to do the conversion it supports.

Drivers set the flags
V4L2_FMT_FLAG_CSC_COLORSPACE,
V4L2_FMT_FLAG_CSC_XFER_FUNC,
V4L2_FMT_FLAG_CSC_YCBCR_ENC/V4L2_FMT_FLAG_CSC_HSV_ENC,
V4L2_FMT_FLAG_CSC_QUANTIZATION,
in the flags field of the struct v4l2_fmtdesc during enumeration to
indicate that they support colorspace conversion for the respective field.

Drivers do not have to actually look at the flags. If the flags are not
set, then the fields 'colorspace', 'xfer_func', 'ycbcr_enc/hsv_enc',
and 'quantization' are set to the default values by the core, i.e. just
pass on the received format without conversion.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-09-26 10:20:57 +02:00
Sergey Senozhatsky
129134e541 media: media/v4l2: remove V4L2_FLAG_MEMORY_NON_CONSISTENT flag
The patch partially reverts some of the UAPI bits of the buffer
cache management hints. Namely, the queue consistency (memory
coherency) user-space hint because, as it turned out, the kernel
implementation of this feature was misusing DMA_ATTR_NON_CONSISTENT.

The patch reverts both kernel and user space parts: removes the
DMA consistency attr functions, rolls back changes to v4l2_requestbuffers,
v4l2_create_buffers structures and corresponding UAPI functions
(plus compat32 layer) and cleans up the documentation.

[hverkuil: fixed a few typos in the commit log]
[hverkuil: fixed vb2_core_reqbufs call in drivers/media/dvb-core/dvb_vb2.c]
[mchehab: fixed a typo in the commit log: revers->reverts]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-09-14 15:28:06 +02:00
Hans Verkuil
b305dfe2e9 media: videodev2.h: RGB BT2020 and HSV are always full range
The default RGB quantization range for BT.2020 is full range (just as for
all the other RGB pixel encodings), not limited range.

Update the V4L2_MAP_QUANTIZATION_DEFAULT macro and documentation
accordingly.

Also mention that HSV is always full range and cannot be limited range.

When RGB BT2020 was introduced in V4L2 it was not clear whether it should
be limited or full range, but full range is the right (and consistent)
choice.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-08-26 16:39:35 +02:00
Ezequiel Garcia
b3ab1c6058 media: Add V4L2_TYPE_IS_CAPTURE helper
It's all too easy to get confused by the V4L2_TYPE_IS_OUTPUT
macro, when it's used as !V4L2_TYPE_IS_OUTPUT.

Reduce the risk of confusion with macro to explicitly
check for the CAPTURE queue type case.

This change does not affect functionality, and it's
only intended to make the code more readable.

Suggested-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: checkpatch: align with parenthesis]
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-07-19 08:13:24 +02:00
Hans Verkuil
286cf7d3a9 media: videodev2.h: add V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL flag
Add the V4L2_FMT_FLAG_ENC_CAP_FRAME_INTERVAL flag to signal that
the coded frame interval can be set separately from the raw frame
interval for stateful encoders.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Michael Tretter <m.tretter@pengutronix.de>
Acked-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-06-23 14:02:46 +02:00
Sergey Senozhatsky
1e0b2318fa media: videobuf2: handle V4L2_FLAG_MEMORY_NON_CONSISTENT flag
This patch lets user-space to request a non-consistent memory
allocation during CREATE_BUFS and REQBUFS ioctl calls.

= CREATE_BUFS

  struct v4l2_create_buffers has seven 4-byte reserved areas,
  so reserved[0] is renamed to ->flags. The struct, thus, now
  has six reserved 4-byte regions.

= CREATE_BUFS32

  struct v4l2_create_buffers32 has seven 4-byte reserved areas,
  so reserved[0] is renamed to ->flags. The struct, thus, now
  has six reserved 4-byte regions.

= REQBUFS

 We use one bit of a ->reserved[1] member of struct v4l2_requestbuffers,
 which is now renamed to ->flags. Unlike v4l2_create_buffers, struct
 v4l2_requestbuffers does not have enough reserved room. Therefore for
 backward compatibility  ->reserved and ->flags were put into anonymous
 union.

Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-06-23 13:32:41 +02:00
Sergey Senozhatsky
ac53503ee3 media: videobuf2: add V4L2_FLAG_MEMORY_NON_CONSISTENT flag
By setting or clearing V4L2_FLAG_MEMORY_NON_CONSISTENT flag
user-space should be able to set or clear queue's NON_CONSISTENT
->dma_attrs. Queue's ->dma_attrs are passed to the underlying
allocator in __vb2_buf_mem_alloc(), so thus user-space is able
to request vb2 buffer's memory to be either consistent (coherent)
or non-consistent.

The patch set also adds a corresponding capability flag:
fill_buf_caps() reports V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS
when queue supports user-space cache management hints. Note,
however, that MMAP_CACHE_HINTS capability only valid when the
queue is used for memory MMAP-ed streaming I/O.

Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-06-23 13:28:17 +02:00