xref: /linux/Documentation/userspace-api/media/dvb/fe-read-ber.rst (revision cbecf716ca618fd44feda6bd9a64a8179d031fc5)
1059b1c5bSMauro Carvalho Chehab.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
2f9b2e8aaSMauro Carvalho Chehab.. c:namespace:: DTV.fe
354f38fcaSMauro Carvalho Chehab
454f38fcaSMauro Carvalho Chehab.. _FE_READ_BER:
554f38fcaSMauro Carvalho Chehab
654f38fcaSMauro Carvalho Chehab***********
754f38fcaSMauro Carvalho ChehabFE_READ_BER
854f38fcaSMauro Carvalho Chehab***********
954f38fcaSMauro Carvalho Chehab
1054f38fcaSMauro Carvalho ChehabName
1154f38fcaSMauro Carvalho Chehab====
1254f38fcaSMauro Carvalho Chehab
1354f38fcaSMauro Carvalho ChehabFE_READ_BER
1454f38fcaSMauro Carvalho Chehab
1554f38fcaSMauro Carvalho Chehab.. attention:: This ioctl is deprecated.
1654f38fcaSMauro Carvalho Chehab
1754f38fcaSMauro Carvalho ChehabSynopsis
1854f38fcaSMauro Carvalho Chehab========
1954f38fcaSMauro Carvalho Chehab
20f9b2e8aaSMauro Carvalho Chehab.. c:macro:: FE_READ_BER
2154f38fcaSMauro Carvalho Chehab
22f9b2e8aaSMauro Carvalho Chehab``int ioctl(int fd, FE_READ_BER, uint32_t *ber)``
2354f38fcaSMauro Carvalho Chehab
2454f38fcaSMauro Carvalho ChehabArguments
2554f38fcaSMauro Carvalho Chehab=========
2654f38fcaSMauro Carvalho Chehab
2754f38fcaSMauro Carvalho Chehab``fd``
28f9b2e8aaSMauro Carvalho Chehab    File descriptor returned by :c:func:`open()`.
2954f38fcaSMauro Carvalho Chehab
3054f38fcaSMauro Carvalho Chehab``ber``
3154f38fcaSMauro Carvalho Chehab    The bit error rate is stored into \*ber.
3254f38fcaSMauro Carvalho Chehab
3354f38fcaSMauro Carvalho ChehabDescription
3454f38fcaSMauro Carvalho Chehab===========
3554f38fcaSMauro Carvalho Chehab
3654f38fcaSMauro Carvalho ChehabThis ioctl call returns the bit error rate for the signal currently
3754f38fcaSMauro Carvalho Chehabreceived/demodulated by the front-end. For this command, read-only
3854f38fcaSMauro Carvalho Chehabaccess to the device is sufficient.
3954f38fcaSMauro Carvalho Chehab
4054f38fcaSMauro Carvalho ChehabReturn Value
4154f38fcaSMauro Carvalho Chehab============
4254f38fcaSMauro Carvalho Chehab
4354f38fcaSMauro Carvalho ChehabOn success 0 is returned.
4454f38fcaSMauro Carvalho Chehab
4554f38fcaSMauro Carvalho ChehabOn error -1 is returned, and the ``errno`` variable is set
4654f38fcaSMauro Carvalho Chehabappropriately.
4754f38fcaSMauro Carvalho Chehab
4854f38fcaSMauro Carvalho ChehabGeneric error codes are described at the
4954f38fcaSMauro Carvalho Chehab:ref:`Generic Error Codes <gen-errors>` chapter.
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