5c7dd7acc3
repo: https://github.com/T-head-Semi/linux commit: b1313fe517ca3703119dcc99ef3bbf75ab42bcfb Change-Id: I6cbb35294024ea3a66140e311f4bb705fd7fd626
50 lines
852 B
ReStructuredText
50 lines
852 B
ReStructuredText
.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
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.. c:namespace:: DTV.fe
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.. _FE_READ_SNR:
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***********
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FE_READ_SNR
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***********
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Name
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====
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FE_READ_SNR
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.. attention:: This ioctl is deprecated.
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Synopsis
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========
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.. c:macro:: FE_READ_SNR
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``int ioctl(int fd, FE_READ_SNR, int16_t *snr)``
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Arguments
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=========
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``fd``
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File descriptor returned by :c:func:`open()`.
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``snr``
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The signal-to-noise ratio is stored into \*snr.
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Description
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===========
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This ioctl call returns the signal-to-noise ratio for the signal
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currently received by the front-end. For this command, read-only access
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to the device is sufficient.
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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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