sound/sof/channel_map.h

0001 /* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */
0002 /*
0003  * This file is provided under a dual BSD/GPLv2 license.  When using or
0004  * redistributing this file, you may do so under either license.
0005  *
0006  * Copyright(c) 2019 Intel Corporation. All rights reserved.
0007  */
0008
0009 #ifndef __IPC_CHANNEL_MAP_H__
0010 #define __IPC_CHANNEL_MAP_H__
0011
0012 #include <uapi/sound/sof/header.h>
0013 #include <sound/sof/header.h>
0014
0015 /**
0016  * \brief Channel map, specifies transformation of one-to-many or many-to-one.
0017  *
0018  * In case of one-to-many specifies how the output channels are computed out of
0019  * a single source channel,
0020  * in case of many-to-one specifies how a single target channel is computed
0021  * from a multichannel input stream.
0022  *
0023  * Channel index specifies position of the channel in the stream on the 'one'
0024  * side.
0025  *
0026  * Ext ID is the identifier of external part of the transformation. Depending
0027  * on the context, it may be pipeline ID, dai ID, ...
0028  *
0029  * Channel mask describes which channels are taken into account on the "many"
0030  * side. Bit[i] set to 1 means that i-th channel is used for computation
0031  * (either as source or as a target).
0032  *
0033  * Channel mask is followed by array of coefficients in Q2.30 format,
0034  * one per each channel set in the mask (left to right, LS bit set in the
0035  * mask corresponds to ch_coeffs[0]).
0036  */
0037 struct sof_ipc_channel_map {
0038     uint32_t ch_index;
0039     uint32_t ext_id;
0040     uint32_t ch_mask;
0041     uint32_t reserved;
0042     int32_t ch_coeffs[];
0043 } __packed;
0044
0045 /**
0046  * \brief Complete map for each channel of a multichannel stream.
0047  *
0048  * num_ch_map Specifies number of items in the ch_map.
0049  * More than one transformation per a single channel is allowed (in case
0050  * multiple external entities are transformed).
0051  * A channel may be skipped in the transformation list, then it is filled
0052  * with 0's by the transformation function.
0053  */
0054 struct sof_ipc_stream_map {
0055     struct sof_ipc_cmd_hdr hdr;
0056     uint32_t num_ch_map;
0057     uint32_t reserved[3];
0058     struct sof_ipc_channel_map ch_map[];
0059 } __packed;
0060
0061 #endif /* __IPC_CHANNEL_MAP_H__ */