1 /*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #define LOG_TAG "alsa_format"
18 /*#define LOG_NDEBUG 0*/
19
20 #include "include/alsa_format.h"
21
22 #include <tinyalsa/asoundlib.h>
23
24 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
25
26 /*
27 * Maps from bit position in pcm_mask to PCM_ format constants.
28 */
29 int8_t const pcm_format_value_map[50] = {
30 PCM_FORMAT_S8, /* 00 - SNDRV_PCM_FORMAT_S8 */
31 PCM_FORMAT_INVALID, /* 01 - SNDRV_PCM_FORMAT_U8 */
32 PCM_FORMAT_S16_LE, /* 02 - SNDRV_PCM_FORMAT_S16_LE */
33 PCM_FORMAT_INVALID, /* 03 - SNDRV_PCM_FORMAT_S16_BE */
34 PCM_FORMAT_INVALID, /* 04 - SNDRV_PCM_FORMAT_U16_LE */
35 PCM_FORMAT_INVALID, /* 05 - SNDRV_PCM_FORMAT_U16_BE */
36 PCM_FORMAT_S24_LE, /* 06 - SNDRV_PCM_FORMAT_S24_LE */
37 PCM_FORMAT_INVALID, /* 07 - SNDRV_PCM_FORMAT_S24_BE */
38 PCM_FORMAT_INVALID, /* 08 - SNDRV_PCM_FORMAT_U24_LE */
39 PCM_FORMAT_INVALID, /* 09 - SNDRV_PCM_FORMAT_U24_BE */
40 PCM_FORMAT_S32_LE, /* 10 - SNDRV_PCM_FORMAT_S32_LE */
41 PCM_FORMAT_INVALID, /* 11 - SNDRV_PCM_FORMAT_S32_BE */
42 PCM_FORMAT_INVALID, /* 12 - SNDRV_PCM_FORMAT_U32_LE */
43 PCM_FORMAT_INVALID, /* 13 - SNDRV_PCM_FORMAT_U32_BE */
44 PCM_FORMAT_INVALID, /* 14 - SNDRV_PCM_FORMAT_FLOAT_LE */
45 PCM_FORMAT_INVALID, /* 15 - SNDRV_PCM_FORMAT_FLOAT_BE */
46 PCM_FORMAT_INVALID, /* 16 - SNDRV_PCM_FORMAT_FLOAT64_LE */
47 PCM_FORMAT_INVALID, /* 17 - SNDRV_PCM_FORMAT_FLOAT64_BE */
48 PCM_FORMAT_INVALID, /* 18 - SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE */
49 PCM_FORMAT_INVALID, /* 19 - SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE */
50 PCM_FORMAT_INVALID, /* 20 - SNDRV_PCM_FORMAT_MU_LAW */
51 PCM_FORMAT_INVALID, /* 21 - SNDRV_PCM_FORMAT_A_LAW */
52 PCM_FORMAT_INVALID, /* 22 - SNDRV_PCM_FORMAT_IMA_ADPCM */
53 PCM_FORMAT_INVALID, /* 23 - SNDRV_PCM_FORMAT_MPEG */
54 PCM_FORMAT_INVALID, /* 24 - SNDRV_PCM_FORMAT_GSM */
55 PCM_FORMAT_INVALID, /* 25 -> 30 (not assigned) */
56 PCM_FORMAT_INVALID,
57 PCM_FORMAT_INVALID,
58 PCM_FORMAT_INVALID,
59 PCM_FORMAT_INVALID,
60 PCM_FORMAT_INVALID,
61 PCM_FORMAT_INVALID, /* 31 - SNDRV_PCM_FORMAT_SPECIAL */
62 PCM_FORMAT_S24_3LE, /* 32 - SNDRV_PCM_FORMAT_S24_3LE */
63 PCM_FORMAT_INVALID, /* 33 - SNDRV_PCM_FORMAT_S24_3BE */
64 PCM_FORMAT_INVALID, /* 34 - SNDRV_PCM_FORMAT_U24_3LE */
65 PCM_FORMAT_INVALID, /* 35 - SNDRV_PCM_FORMAT_U24_3BE */
66 PCM_FORMAT_INVALID, /* 36 - SNDRV_PCM_FORMAT_S20_3LE */
67 PCM_FORMAT_INVALID, /* 37 - SNDRV_PCM_FORMAT_S20_3BE */
68 PCM_FORMAT_INVALID, /* 38 - SNDRV_PCM_FORMAT_U20_3LE */
69 PCM_FORMAT_INVALID, /* 39 - SNDRV_PCM_FORMAT_U20_3BE */
70 PCM_FORMAT_INVALID, /* 40 - SNDRV_PCM_FORMAT_S18_3LE */
71 PCM_FORMAT_INVALID, /* 41 - SNDRV_PCM_FORMAT_S18_3BE */
72 PCM_FORMAT_INVALID, /* 42 - SNDRV_PCM_FORMAT_U18_3LE */
73 PCM_FORMAT_INVALID, /* 43 - SNDRV_PCM_FORMAT_U18_3BE */
74 PCM_FORMAT_INVALID, /* 44 - SNDRV_PCM_FORMAT_G723_24 */
75 PCM_FORMAT_INVALID, /* 45 - SNDRV_PCM_FORMAT_G723_24_1B */
76 PCM_FORMAT_INVALID, /* 46 - SNDRV_PCM_FORMAT_G723_40 */
77 PCM_FORMAT_INVALID, /* 47 - SNDRV_PCM_FORMAT_G723_40_1B */
78 PCM_FORMAT_INVALID, /* 48 - SNDRV_PCM_FORMAT_DSD_U8 */
79 PCM_FORMAT_INVALID /* 49 - SNDRV_PCM_FORMAT_DSD_U16_LE */
80 };
81
82 /*
83 * Scans the provided format mask and returns the first non-8 bit sample
84 * format supported by the devices.
85 */
get_pcm_format_for_mask(const struct pcm_mask * mask)86 enum pcm_format get_pcm_format_for_mask(const struct pcm_mask* mask)
87 {
88 int num_slots = ARRAY_SIZE(mask->bits);
89 int bits_per_slot = sizeof(mask->bits[0]) * 8;
90
91 int table_size = ARRAY_SIZE(pcm_format_value_map);
92
93 int slot_index, bit_index, table_index;
94 table_index = 0;
95 for (slot_index = 0; slot_index < num_slots && table_index < table_size; slot_index++) {
96 unsigned bit_mask = 1;
97 for (bit_index = 0; bit_index < bits_per_slot && table_index < table_size; bit_index++) {
98 /* skip any 8-bit formats */
99 if (table_index >= 2 && (mask->bits[slot_index] & bit_mask) != 0) {
100 /* just return the first one which will be at least 16-bit */
101 return (int)pcm_format_value_map[table_index];
102 }
103 bit_mask <<= 1;
104 table_index++;
105 }
106 }
107
108 return PCM_FORMAT_INVALID;
109 }
110