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1 /* Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
2  * Use of this source code is governed by a BSD-style license that can be
3  * found in the LICENSE file.
4  */
5 
6 #include <stdlib.h>
7 #include <sys/param.h>
8 
9 #include "cras_audio_area.h"
10 #include "cras_audio_format.h"
11 #include "cras_mix.h"
12 
cras_audio_area_create(int num_channels)13 struct cras_audio_area *cras_audio_area_create(int num_channels)
14 {
15 	struct cras_audio_area *area;
16 	size_t sz;
17 
18 	sz = sizeof(*area) + num_channels * sizeof(struct cras_channel_area);
19 	area = calloc(1, sz);
20 	area->num_channels = num_channels;
21 
22 	return area;
23 }
24 
cras_audio_area_copy(const struct cras_audio_area * dst,unsigned int dst_offset,const struct cras_audio_format * dst_fmt,const struct cras_audio_area * src,unsigned int src_offset,float software_gain_scaler)25 unsigned int cras_audio_area_copy(const struct cras_audio_area *dst,
26 				  unsigned int dst_offset,
27 				  const struct cras_audio_format *dst_fmt,
28 				  const struct cras_audio_area *src,
29 				  unsigned int src_offset,
30 				  float software_gain_scaler)
31 {
32 	unsigned int src_idx, dst_idx;
33 	unsigned int ncopy;
34 	uint8_t *schan, *dchan;
35 
36 	ncopy = MIN(src->frames - src_offset, dst->frames - dst_offset);
37 
38 	/* TODO(dgreid) - this replaces a memcpy, it needs to be way faster. */
39 	for (src_idx = 0; src_idx < src->num_channels; src_idx++) {
40 		for (dst_idx = 0; dst_idx < dst->num_channels; dst_idx++) {
41 			if (!(src->channels[src_idx].ch_set &
42 			      dst->channels[dst_idx].ch_set))
43 				continue;
44 
45 			schan = src->channels[src_idx].buf +
46 				src_offset * src->channels[src_idx].step_bytes;
47 			dchan = dst->channels[dst_idx].buf +
48 				dst_offset * dst->channels[dst_idx].step_bytes;
49 
50 			cras_mix_add_scale_stride(
51 				dst_fmt->format, dchan, schan, ncopy,
52 				dst->channels[dst_idx].step_bytes,
53 				src->channels[src_idx].step_bytes,
54 				software_gain_scaler);
55 		}
56 	}
57 
58 	return ncopy;
59 }
60 
cras_audio_area_destroy(struct cras_audio_area * area)61 void cras_audio_area_destroy(struct cras_audio_area *area)
62 {
63 	free(area);
64 }
65 
cras_audio_area_config_channels(struct cras_audio_area * area,const struct cras_audio_format * fmt)66 void cras_audio_area_config_channels(struct cras_audio_area *area,
67 				     const struct cras_audio_format *fmt)
68 {
69 	unsigned int i, ch;
70 
71 	/* For mono, config the channel type to match both front
72 	 * left and front right.
73 	 * TODO(hychao): add more mapping when we have like {FL, FC}
74 	 * for mono + kb mic.
75 	 */
76 	if ((fmt->num_channels == 1) &&
77 	    ((fmt->channel_layout[CRAS_CH_FC] == 0) ||
78 	     (fmt->channel_layout[CRAS_CH_FL] == 0))) {
79 		channel_area_set_channel(area->channels, CRAS_CH_FL);
80 		channel_area_set_channel(area->channels, CRAS_CH_FR);
81 		return;
82 	}
83 
84 	for (i = 0; i < fmt->num_channels; i++) {
85 		area->channels[i].ch_set = 0;
86 		for (ch = 0; ch < CRAS_CH_MAX; ch++)
87 			if (fmt->channel_layout[ch] == i)
88 				channel_area_set_channel(&area->channels[i],
89 							 ch);
90 	}
91 }
92 
cras_audio_area_config_buf_pointers(struct cras_audio_area * area,const struct cras_audio_format * fmt,uint8_t * base_buffer)93 void cras_audio_area_config_buf_pointers(struct cras_audio_area *area,
94 					 const struct cras_audio_format *fmt,
95 					 uint8_t *base_buffer)
96 {
97 	int i;
98 	const int sample_size = snd_pcm_format_physical_width(fmt->format) / 8;
99 
100 	/* TODO(dgreid) - assuming interleaved audio here for now. */
101 	for (i = 0; i < area->num_channels; i++) {
102 		area->channels[i].step_bytes = cras_get_format_bytes(fmt);
103 		area->channels[i].buf = base_buffer + i * sample_size;
104 	}
105 }
106