Commit 0cf35e84 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab

[media] DocBook: document typedef dmx_ts_cb at demux.h

The dvb/kdapi.tmpl has already an extensive documentation about
this callback. Now that we've added function typedefs at kernel-doc,
add such documentation at demux.h, for it to appear at device-drivers
Signed-off-by: default avatarMauro Carvalho Chehab <>
parent 83766452
......@@ -195,6 +195,61 @@ struct dmx_section_feed {
* Callback functions
* typedef dmx_ts_cb - DVB demux TS filter callback function prototype
* @buffer1: Pointer to the start of the filtered TS packets.
* @buffer1_length: Length of the TS data in buffer1.
* @buffer2: Pointer to the tail of the filtered TS packets, or NULL.
* @buffer2_length: Length of the TS data in buffer2.
* @source: Indicates which TS feed is the source of the callback.
* This function callback prototype, provided by the client of the demux API,
* is called from the demux code. The function is only called when filtering
* on ae TS feed has been enabled using the start_filtering() function at
* the &dmx_demux.
* Any TS packets that match the filter settings are copied to a circular
* buffer. The filtered TS packets are delivered to the client using this
* callback function. The size of the circular buffer is controlled by the
* circular_buffer_size parameter of the &dmx_ts_feed.@set function.
* It is expected that the @buffer1 and @buffer2 callback parameters point to
* addresses within the circular buffer, but other implementations are also
* possible. Note that the called party should not try to free the memory
* the @buffer1 and @buffer2 parameters point to.
* When this function is called, the @buffer1 parameter typically points to
* the start of the first undelivered TS packet within a circular buffer.
* The @buffer2 buffer parameter is normally NULL, except when the received
* TS packets have crossed the last address of the circular buffer and
* ”wrapped” to the beginning of the buffer. In the latter case the @buffer1
* parameter would contain an address within the circular buffer, while the
* @buffer2 parameter would contain the first address of the circular buffer.
* The number of bytes delivered with this function (i.e. @buffer1_length +
* @buffer2_length) is usually equal to the value of callback_length parameter
* given in the set() function, with one exception: if a timeout occurs before
* receiving callback_length bytes of TS data, any undelivered packets are
* immediately delivered to the client by calling this function. The timeout
* duration is controlled by the set() function in the TS Feed API.
* If a TS packet is received with errors that could not be fixed by the
* TS-level forward error correction (FEC), the Transport_error_indicator
* flag of the TS packet header should be set. The TS packet should not be
* discarded, as the error can possibly be corrected by a higher layer
* protocol. If the called party is slow in processing the callback, it
* is possible that the circular buffer eventually fills up. If this happens,
* the demux driver should discard any TS packets received while the buffer
* is full and return -EOVERFLOW.
* The type of data returned to the callback can be selected by the
* &dmx_ts_feed.@set function. The type parameter decides if the raw
* TS packet (TS_PACKET) or just the payload (TS_PACKET|TS_PAYLOAD_ONLY)
* should be returned. If additionally the TS_DECODER bit is set the stream
* will also be sent to the hardware MPEG decoder.
* Return:
* 0, on success;
* -EOVERFLOW, on buffer overflow.
typedef int (*dmx_ts_cb)(const u8 *buffer1,
size_t buffer1_length,
const u8 *buffer2,
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