LXR linux/include/sound/sof/channel

   1/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */
   2/*
   3 * This file is provided under a dual BSD/GPLv2 license.  When using or
   4 * redistributing this file, you may do so under either license.
   5 *
   6 * Copyright(c) 2019 Intel Corporation. All rights reserved.
   7 */
   8
   9#ifndef __IPC_CHANNEL_MAP_H__
  10#define __IPC_CHANNEL_MAP_H__
  11
  12#include <uapi/sound/sof/header.h>
  13#include <sound/sof/header.h>
  14
  15/**
  16 * \brief Channel map, specifies transformation of one-to-many or many-to-one.
  17 *
  18 * In case of one-to-many specifies how the output channels are computed out of
  19 * a single source channel,
  20 * in case of many-to-one specifies how a single target channel is computed
  21 * from a multichannel input stream.
  22 *
  23 * Channel index specifies position of the channel in the stream on the 'one'
  24 * side.
  25 *
  26 * Ext ID is the identifier of external part of the transformation. Depending
  27 * on the context, it may be pipeline ID, dai ID, ...
  28 *
  29 * Channel mask describes which channels are taken into account on the "many"
  30 * side. Bit[i] set to 1 means that i-th channel is used for computation
  31 * (either as source or as a target).
  32 *
  33 * Channel mask is followed by array of coefficients in Q2.30 format,
  34 * one per each channel set in the mask (left to right, LS bit set in the
  35 * mask corresponds to ch_coeffs[0]).
  36 */
  37struct sof_ipc_channel_map {
  38        uint32_t ch_index;
  39        uint32_t ext_id;
  40        uint32_t ch_mask;
  41        uint32_t reserved;
  42        int32_t ch_coeffs[0];
  43} __packed;
  44
  45/**
  46 * \brief Complete map for each channel of a multichannel stream.
  47 *
  48 * num_ch_map Specifies number of items in the ch_map.
  49 * More than one transformation per a single channel is allowed (in case
  50 * multiple external entities are transformed).
  51 * A channel may be skipped in the transformation list, then it is filled
  52 * with 0's by the transformation function.
  53 */
  54struct sof_ipc_stream_map {
  55        struct sof_ipc_cmd_hdr hdr;
  56        uint32_t num_ch_map;
  57        uint32_t reserved[3];
  58        struct sof_ipc_channel_map ch_map[0];
  59} __packed;
  60
  61#endif /* __IPC_CHANNEL_MAP_H__ */
  62