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Diffstat (limited to 'Documentation/media/kapi/dtv-common.rst')
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diff --git a/Documentation/media/kapi/dtv-common.rst b/Documentation/media/kapi/dtv-common.rst deleted file mode 100644 index f8b2c4dc8170..000000000000 --- a/Documentation/media/kapi/dtv-common.rst +++ /dev/null @@ -1,62 +0,0 @@ -.. SPDX-License-Identifier: GPL-2.0 - -Digital TV Common functions ---------------------------- - -Math functions -~~~~~~~~~~~~~~ - -Provide some commonly-used math functions, usually required in order to -estimate signal strength and signal to noise measurements in dB. - -.. kernel-doc:: include/media/dvb_math.h - - -DVB devices -~~~~~~~~~~~ - -Those functions are responsible for handling the DVB device nodes. - -.. kernel-doc:: include/media/dvbdev.h - -Digital TV Ring buffer -~~~~~~~~~~~~~~~~~~~~~~ - -Those routines implement ring buffers used to handle digital TV data and -copy it from/to userspace. - -.. note:: - - 1) For performance reasons read and write routines don't check buffer sizes - and/or number of bytes free/available. This has to be done before these - routines are called. For example: - - .. code-block:: c - - /* write @buflen: bytes */ - free = dvb_ringbuffer_free(rbuf); - if (free >= buflen) - count = dvb_ringbuffer_write(rbuf, buffer, buflen); - else - /* do something */ - - /* read min. 1000, max. @bufsize: bytes */ - avail = dvb_ringbuffer_avail(rbuf); - if (avail >= 1000) - count = dvb_ringbuffer_read(rbuf, buffer, min(avail, bufsize)); - else - /* do something */ - - 2) If there is exactly one reader and one writer, there is no need - to lock read or write operations. - Two or more readers must be locked against each other. - Flushing the buffer counts as a read operation. - Resetting the buffer counts as a read and write operation. - Two or more writers must be locked against each other. - -.. kernel-doc:: include/media/dvb_ringbuffer.h - -Digital TV VB2 handler -~~~~~~~~~~~~~~~~~~~~~~ - -.. kernel-doc:: include/media/dvb_vb2.h |