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authorLinus Torvalds <torvalds@linux-foundation.org>2020-06-03 20:59:38 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-03 20:59:38 -0700
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Merge tag 'media/v5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab: - Media documentation is now split into admin-guide, driver-api and userspace-api books (a longstanding request from Jon); - The media Kconfig was reorganized, in order to make easier to select drivers and their dependencies; - The testing drivers now has a separate directory; - added a new driver for Rockchip Video Decoder IP; - The atomisp staging driver was resurrected. It is meant to work with 4 generations of cameras on Atom-based laptops, tablets and cell phones. So, it seems worth investing time to cleanup this driver and making it in good shape. - Added some V4L2 core ancillary routines to help with h264 codecs; - Added an ov2740 image sensor driver; - The si2157 gained support for Analog TV, which, in turn, added support for some cx231xx and cx23885 boards to also support analog standards; - Added some V4L2 controls (V4L2_CID_CAMERA_ORIENTATION and V4L2_CID_CAMERA_SENSOR_ROTATION) to help identifying where the camera is located at the device; - VIDIOC_ENUM_FMT was extended to support MC-centric devices; - Lots of drivers improvements and cleanups. * tag 'media/v5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (503 commits) media: Documentation: media: Refer to mbus format documentation from CSI-2 docs media: s5k5baf: Replace zero-length array with flexible-array media: i2c: imx219: Drop <linux/clk-provider.h> and <linux/clkdev.h> media: i2c: Add ov2740 image sensor driver media: ov8856: Implement sensor module revision identification media: ov8856: Add devicetree support media: dt-bindings: ov8856: Document YAML bindings media: dvb-usb: Add Cinergy S2 PCIe Dual Port support media: dvbdev: Fix tuner->demod media controller link media: dt-bindings: phy: phy-rockchip-dphy-rx0: move rockchip dphy rx0 bindings out of staging media: staging: dt-bindings: phy-rockchip-dphy-rx0: remove non-used reg property media: atomisp: unify the version for isp2401 a0 and b0 versions media: atomisp: update TODO with the current data media: atomisp: adjust some code at sh_css that could be broken media: atomisp: don't produce errs for ignored IRQs media: atomisp: print IRQ when debugging media: atomisp: isp_mmu: don't use kmem_cache media: atomisp: add a notice about possible leak resources media: atomisp: disable the dynamic and reserved pools media: atomisp: turn on camera before setting it ...
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+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _dmx_fread:
+
+=======================
+Digital TV demux read()
+=======================
+
+Name
+----
+
+Digital TV demux read()
+
+
+Synopsis
+--------
+
+.. c:function:: size_t read(int fd, void *buf, size_t count)
+ :name: dvb-dmx-read
+
+Arguments
+---------
+
+``fd``
+ File descriptor returned by a previous call to :c:func:`open() <dvb-ca-open>`.
+
+ ``buf``
+ Buffer to be filled
+
+``count``
+ Max number of bytes to read
+
+Description
+-----------
+
+This system call returns filtered data, which might be section or Packetized
+Elementary Stream (PES) data. The filtered data is transferred from
+the driver’s internal circular buffer to ``buf``. The maximum amount of data
+to be transferred is implied by count.
+
+.. note::
+
+ if a section filter created with
+ :c:type:`DMX_CHECK_CRC <dmx_sct_filter_params>` flag set,
+ data that fails on CRC check will be silently ignored.
+
+
+Return Value
+------------
+
+On success 0 is returned.
+
+On error -1 is returned, and the ``errno`` variable is set
+appropriately.
+
+.. tabularcolumns:: |p{2.5cm}|p{15.0cm}|
+
+.. flat-table::
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 16
+
+ - - ``EWOULDBLOCK``
+ - No data to return and ``O_NONBLOCK`` was specified.
+
+ - - ``EOVERFLOW``
+ - The filtered data was not read from the buffer in due time,
+ resulting in non-read data being lost. The buffer is flushed.
+
+ - - ``ETIMEDOUT``
+ - The section was not loaded within the stated timeout period.
+ See ioctl :ref:`DMX_SET_FILTER` for how to set a timeout.
+
+ - - ``EFAULT``
+ - The driver failed to write to the callers buffer due to an
+ invalid \*buf pointer.
+
+
+The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.