54f38fcae5
Since 2017, there is an space reserved for userspace API,
created by changeset 1d596dee3862 ("docs: Create a user-space API guide").
As the media subsystem was one of the first subsystems to use
Sphinx, until this patch, we were keeping things on a separate
place.
Let's just use the new location, as having all uAPI altogether
will likely make things easier for developers.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
73 lines
1.8 KiB
ReStructuredText
73 lines
1.8 KiB
ReStructuredText
.. Permission is granted to copy, distribute and/or modify this
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.. document under the terms of the GNU Free Documentation License,
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.. Version 1.1 or any later version published by the Free Software
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.. Foundation, with no Invariant Sections, no Front-Cover Texts
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.. and no Back-Cover Texts. A copy of the license is included at
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.. Documentation/userspace-api/media/fdl-appendix.rst.
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..
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.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
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.. _FE_READ_STATUS:
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********************
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ioctl FE_READ_STATUS
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********************
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Name
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====
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FE_READ_STATUS - Returns status information about the front-end. This call only requires - read-only access to the device
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Synopsis
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========
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.. c:function:: int ioctl( int fd, FE_READ_STATUS, unsigned int *status )
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:name: FE_READ_STATUS
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Arguments
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=========
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``fd``
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File descriptor returned by :ref:`open() <frontend_f_open>`.
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``status``
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pointer to a bitmask integer filled with the values defined by enum
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:c:type:`fe_status`.
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Description
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===========
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All Digital TV frontend devices support the ``FE_READ_STATUS`` ioctl. It is
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used to check about the locking status of the frontend after being
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tuned. The ioctl takes a pointer to an integer where the status will be
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written.
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.. note::
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The size of status is actually sizeof(enum fe_status), with
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varies according with the architecture. This needs to be fixed in the
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future.
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int fe_status
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=============
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The fe_status parameter is used to indicate the current state and/or
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state changes of the frontend hardware. It is produced using the enum
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:c:type:`fe_status` values on a bitmask
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Return Value
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============
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On success 0 is returned.
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On error -1 is returned, and the ``errno`` variable is set
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appropriately.
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Generic error codes are described at the
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:ref:`Generic Error Codes <gen-errors>` chapter.
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