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diff --git a/Documentation/userspace-api/media/rc/lirc-get-rec-resolution.rst b/Documentation/userspace-api/media/rc/lirc-get-rec-resolution.rst new file mode 100644 index 000000000000..f20b5bf41232 --- /dev/null +++ b/Documentation/userspace-api/media/rc/lirc-get-rec-resolution.rst @@ -0,0 +1,54 @@ +.. 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 + +.. _lirc_get_rec_resolution: + +***************************** +ioctl LIRC_GET_REC_RESOLUTION +***************************** + +Name +==== + +LIRC_GET_REC_RESOLUTION - Obtain the value of receive resolution, in microseconds. + +Synopsis +======== + +.. c:function:: int ioctl( int fd, LIRC_GET_REC_RESOLUTION, __u32 *microseconds) + :name: LIRC_GET_REC_RESOLUTION + +Arguments +========= + +``fd`` + File descriptor returned by open(). + +``microseconds`` + Resolution, in microseconds. + + +Description +=========== + +Some receivers have maximum resolution which is defined by internal +sample rate or data format limitations. E.g. it's common that +signals can only be reported in 50 microsecond steps. + +This ioctl returns the integer value with such resolution, with can be +used by userspace applications like lircd to automatically adjust the +tolerance value. + + +Return Value +============ + +On success 0 is returned, on error -1 and the ``errno`` variable is set +appropriately. The generic error codes are described at the +:ref:`Generic Error Codes <gen-errors>` chapter. |