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612 lines
16 KiB
612 lines
16 KiB
/* |
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* PCM Interface - misc routines |
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* Copyright (c) 1998 by Jaroslav Kysela <[email protected]> |
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* |
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* |
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* This library is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU Library General Public License as |
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* published by the Free Software Foundation; either version 2 of |
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* the License, or (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU Library General Public License for more details. |
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* |
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* You should have received a copy of the GNU Library General Public |
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* License along with this library; if not, write to the Free Software |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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* |
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*/ |
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#include <linux/time.h> |
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#include <linux/export.h> |
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#include <sound/core.h> |
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#include <sound/pcm.h> |
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#include "pcm_local.h" |
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#define SND_PCM_FORMAT_UNKNOWN (-1) |
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/* NOTE: "signed" prefix must be given below since the default char is |
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* unsigned on some architectures! |
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*/ |
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struct pcm_format_data { |
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unsigned char width; /* bit width */ |
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unsigned char phys; /* physical bit width */ |
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signed char le; /* 0 = big-endian, 1 = little-endian, -1 = others */ |
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signed char signd; /* 0 = unsigned, 1 = signed, -1 = others */ |
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unsigned char silence[8]; /* silence data to fill */ |
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}; |
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/* we do lots of calculations on snd_pcm_format_t; shut up sparse */ |
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#define INT __force int |
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static bool valid_format(snd_pcm_format_t format) |
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{ |
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return (INT)format >= 0 && (INT)format <= (INT)SNDRV_PCM_FORMAT_LAST; |
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} |
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static const struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = { |
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[SNDRV_PCM_FORMAT_S8] = { |
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.width = 8, .phys = 8, .le = -1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U8] = { |
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.width = 8, .phys = 8, .le = -1, .signd = 0, |
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.silence = { 0x80 }, |
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}, |
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[SNDRV_PCM_FORMAT_S16_LE] = { |
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.width = 16, .phys = 16, .le = 1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_S16_BE] = { |
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.width = 16, .phys = 16, .le = 0, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U16_LE] = { |
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.width = 16, .phys = 16, .le = 1, .signd = 0, |
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.silence = { 0x00, 0x80 }, |
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}, |
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[SNDRV_PCM_FORMAT_U16_BE] = { |
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.width = 16, .phys = 16, .le = 0, .signd = 0, |
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.silence = { 0x80, 0x00 }, |
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}, |
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[SNDRV_PCM_FORMAT_S24_LE] = { |
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.width = 24, .phys = 32, .le = 1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_S24_BE] = { |
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.width = 24, .phys = 32, .le = 0, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U24_LE] = { |
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.width = 24, .phys = 32, .le = 1, .signd = 0, |
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.silence = { 0x00, 0x00, 0x80 }, |
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}, |
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[SNDRV_PCM_FORMAT_U24_BE] = { |
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.width = 24, .phys = 32, .le = 0, .signd = 0, |
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.silence = { 0x00, 0x80, 0x00, 0x00 }, |
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}, |
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[SNDRV_PCM_FORMAT_S32_LE] = { |
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.width = 32, .phys = 32, .le = 1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_S32_BE] = { |
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.width = 32, .phys = 32, .le = 0, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U32_LE] = { |
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.width = 32, .phys = 32, .le = 1, .signd = 0, |
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.silence = { 0x00, 0x00, 0x00, 0x80 }, |
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}, |
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[SNDRV_PCM_FORMAT_U32_BE] = { |
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.width = 32, .phys = 32, .le = 0, .signd = 0, |
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.silence = { 0x80, 0x00, 0x00, 0x00 }, |
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}, |
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[SNDRV_PCM_FORMAT_FLOAT_LE] = { |
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.width = 32, .phys = 32, .le = 1, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_FLOAT_BE] = { |
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.width = 32, .phys = 32, .le = 0, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_FLOAT64_LE] = { |
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.width = 64, .phys = 64, .le = 1, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_FLOAT64_BE] = { |
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.width = 64, .phys = 64, .le = 0, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = { |
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.width = 32, .phys = 32, .le = 1, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = { |
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.width = 32, .phys = 32, .le = 0, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_MU_LAW] = { |
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.width = 8, .phys = 8, .le = -1, .signd = -1, |
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.silence = { 0x7f }, |
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}, |
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[SNDRV_PCM_FORMAT_A_LAW] = { |
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.width = 8, .phys = 8, .le = -1, .signd = -1, |
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.silence = { 0x55 }, |
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}, |
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[SNDRV_PCM_FORMAT_IMA_ADPCM] = { |
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.width = 4, .phys = 4, .le = -1, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_G723_24] = { |
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.width = 3, .phys = 3, .le = -1, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_G723_40] = { |
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.width = 5, .phys = 5, .le = -1, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_DSD_U8] = { |
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.width = 8, .phys = 8, .le = 1, .signd = 0, |
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.silence = { 0x69 }, |
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}, |
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[SNDRV_PCM_FORMAT_DSD_U16_LE] = { |
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.width = 16, .phys = 16, .le = 1, .signd = 0, |
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.silence = { 0x69, 0x69 }, |
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}, |
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[SNDRV_PCM_FORMAT_DSD_U32_LE] = { |
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.width = 32, .phys = 32, .le = 1, .signd = 0, |
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.silence = { 0x69, 0x69, 0x69, 0x69 }, |
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}, |
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[SNDRV_PCM_FORMAT_DSD_U16_BE] = { |
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.width = 16, .phys = 16, .le = 0, .signd = 0, |
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.silence = { 0x69, 0x69 }, |
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}, |
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[SNDRV_PCM_FORMAT_DSD_U32_BE] = { |
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.width = 32, .phys = 32, .le = 0, .signd = 0, |
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.silence = { 0x69, 0x69, 0x69, 0x69 }, |
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}, |
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/* FIXME: the following two formats are not defined properly yet */ |
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[SNDRV_PCM_FORMAT_MPEG] = { |
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.le = -1, .signd = -1, |
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}, |
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[SNDRV_PCM_FORMAT_GSM] = { |
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.le = -1, .signd = -1, |
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}, |
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[SNDRV_PCM_FORMAT_S20_LE] = { |
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.width = 20, .phys = 32, .le = 1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_S20_BE] = { |
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.width = 20, .phys = 32, .le = 0, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U20_LE] = { |
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.width = 20, .phys = 32, .le = 1, .signd = 0, |
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.silence = { 0x00, 0x00, 0x08, 0x00 }, |
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}, |
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[SNDRV_PCM_FORMAT_U20_BE] = { |
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.width = 20, .phys = 32, .le = 0, .signd = 0, |
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.silence = { 0x00, 0x08, 0x00, 0x00 }, |
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}, |
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/* FIXME: the following format is not defined properly yet */ |
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[SNDRV_PCM_FORMAT_SPECIAL] = { |
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.le = -1, .signd = -1, |
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}, |
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[SNDRV_PCM_FORMAT_S24_3LE] = { |
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.width = 24, .phys = 24, .le = 1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_S24_3BE] = { |
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.width = 24, .phys = 24, .le = 0, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U24_3LE] = { |
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.width = 24, .phys = 24, .le = 1, .signd = 0, |
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.silence = { 0x00, 0x00, 0x80 }, |
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}, |
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[SNDRV_PCM_FORMAT_U24_3BE] = { |
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.width = 24, .phys = 24, .le = 0, .signd = 0, |
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.silence = { 0x80, 0x00, 0x00 }, |
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}, |
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[SNDRV_PCM_FORMAT_S20_3LE] = { |
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.width = 20, .phys = 24, .le = 1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_S20_3BE] = { |
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.width = 20, .phys = 24, .le = 0, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U20_3LE] = { |
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.width = 20, .phys = 24, .le = 1, .signd = 0, |
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.silence = { 0x00, 0x00, 0x08 }, |
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}, |
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[SNDRV_PCM_FORMAT_U20_3BE] = { |
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.width = 20, .phys = 24, .le = 0, .signd = 0, |
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.silence = { 0x08, 0x00, 0x00 }, |
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}, |
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[SNDRV_PCM_FORMAT_S18_3LE] = { |
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.width = 18, .phys = 24, .le = 1, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_S18_3BE] = { |
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.width = 18, .phys = 24, .le = 0, .signd = 1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_U18_3LE] = { |
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.width = 18, .phys = 24, .le = 1, .signd = 0, |
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.silence = { 0x00, 0x00, 0x02 }, |
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}, |
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[SNDRV_PCM_FORMAT_U18_3BE] = { |
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.width = 18, .phys = 24, .le = 0, .signd = 0, |
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.silence = { 0x02, 0x00, 0x00 }, |
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}, |
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[SNDRV_PCM_FORMAT_G723_24_1B] = { |
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.width = 3, .phys = 8, .le = -1, .signd = -1, |
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.silence = {}, |
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}, |
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[SNDRV_PCM_FORMAT_G723_40_1B] = { |
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.width = 5, .phys = 8, .le = -1, .signd = -1, |
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.silence = {}, |
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}, |
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}; |
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/** |
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* snd_pcm_format_signed - Check the PCM format is signed linear |
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* @format: the format to check |
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* |
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* Return: 1 if the given PCM format is signed linear, 0 if unsigned |
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* linear, and a negative error code for non-linear formats. |
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*/ |
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int snd_pcm_format_signed(snd_pcm_format_t format) |
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{ |
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int val; |
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if (!valid_format(format)) |
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return -EINVAL; |
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if ((val = pcm_formats[(INT)format].signd) < 0) |
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return -EINVAL; |
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return val; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_signed); |
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/** |
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* snd_pcm_format_unsigned - Check the PCM format is unsigned linear |
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* @format: the format to check |
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* |
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* Return: 1 if the given PCM format is unsigned linear, 0 if signed |
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* linear, and a negative error code for non-linear formats. |
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*/ |
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int snd_pcm_format_unsigned(snd_pcm_format_t format) |
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{ |
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int val; |
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val = snd_pcm_format_signed(format); |
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if (val < 0) |
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return val; |
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return !val; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_unsigned); |
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/** |
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* snd_pcm_format_linear - Check the PCM format is linear |
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* @format: the format to check |
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* |
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* Return: 1 if the given PCM format is linear, 0 if not. |
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*/ |
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int snd_pcm_format_linear(snd_pcm_format_t format) |
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{ |
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return snd_pcm_format_signed(format) >= 0; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_linear); |
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/** |
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* snd_pcm_format_little_endian - Check the PCM format is little-endian |
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* @format: the format to check |
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* |
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* Return: 1 if the given PCM format is little-endian, 0 if |
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* big-endian, or a negative error code if endian not specified. |
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*/ |
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int snd_pcm_format_little_endian(snd_pcm_format_t format) |
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{ |
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int val; |
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if (!valid_format(format)) |
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return -EINVAL; |
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if ((val = pcm_formats[(INT)format].le) < 0) |
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return -EINVAL; |
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return val; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_little_endian); |
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/** |
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* snd_pcm_format_big_endian - Check the PCM format is big-endian |
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* @format: the format to check |
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* |
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* Return: 1 if the given PCM format is big-endian, 0 if |
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* little-endian, or a negative error code if endian not specified. |
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*/ |
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int snd_pcm_format_big_endian(snd_pcm_format_t format) |
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{ |
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int val; |
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val = snd_pcm_format_little_endian(format); |
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if (val < 0) |
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return val; |
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return !val; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_big_endian); |
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/** |
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* snd_pcm_format_width - return the bit-width of the format |
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* @format: the format to check |
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* |
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* Return: The bit-width of the format, or a negative error code |
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* if unknown format. |
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*/ |
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int snd_pcm_format_width(snd_pcm_format_t format) |
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{ |
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int val; |
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if (!valid_format(format)) |
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return -EINVAL; |
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if ((val = pcm_formats[(INT)format].width) == 0) |
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return -EINVAL; |
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return val; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_width); |
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/** |
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* snd_pcm_format_physical_width - return the physical bit-width of the format |
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* @format: the format to check |
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* |
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* Return: The physical bit-width of the format, or a negative error code |
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* if unknown format. |
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*/ |
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int snd_pcm_format_physical_width(snd_pcm_format_t format) |
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{ |
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int val; |
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if (!valid_format(format)) |
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return -EINVAL; |
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if ((val = pcm_formats[(INT)format].phys) == 0) |
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return -EINVAL; |
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return val; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_physical_width); |
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/** |
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* snd_pcm_format_size - return the byte size of samples on the given format |
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* @format: the format to check |
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* @samples: sampling rate |
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* |
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* Return: The byte size of the given samples for the format, or a |
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* negative error code if unknown format. |
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*/ |
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ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples) |
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{ |
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int phys_width = snd_pcm_format_physical_width(format); |
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if (phys_width < 0) |
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return -EINVAL; |
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return samples * phys_width / 8; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_size); |
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/** |
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* snd_pcm_format_silence_64 - return the silent data in 8 bytes array |
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* @format: the format to check |
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* |
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* Return: The format pattern to fill or %NULL if error. |
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*/ |
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const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format) |
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{ |
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if (!valid_format(format)) |
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return NULL; |
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if (! pcm_formats[(INT)format].phys) |
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return NULL; |
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return pcm_formats[(INT)format].silence; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_silence_64); |
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/** |
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* snd_pcm_format_set_silence - set the silence data on the buffer |
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* @format: the PCM format |
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* @data: the buffer pointer |
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* @samples: the number of samples to set silence |
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* |
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* Sets the silence data on the buffer for the given samples. |
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* |
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* Return: Zero if successful, or a negative error code on failure. |
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*/ |
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int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples) |
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{ |
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int width; |
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unsigned char *dst; |
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const unsigned char *pat; |
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if (!valid_format(format)) |
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return -EINVAL; |
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if (samples == 0) |
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return 0; |
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width = pcm_formats[(INT)format].phys; /* physical width */ |
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pat = pcm_formats[(INT)format].silence; |
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if (! width) |
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return -EINVAL; |
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/* signed or 1 byte data */ |
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if (pcm_formats[(INT)format].signd == 1 || width <= 8) { |
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unsigned int bytes = samples * width / 8; |
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memset(data, *pat, bytes); |
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return 0; |
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} |
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/* non-zero samples, fill using a loop */ |
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width /= 8; |
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dst = data; |
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#if 0 |
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while (samples--) { |
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memcpy(dst, pat, width); |
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dst += width; |
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} |
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#else |
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/* a bit optimization for constant width */ |
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switch (width) { |
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case 2: |
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while (samples--) { |
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memcpy(dst, pat, 2); |
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dst += 2; |
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} |
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break; |
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case 3: |
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while (samples--) { |
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memcpy(dst, pat, 3); |
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dst += 3; |
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} |
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break; |
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case 4: |
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while (samples--) { |
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memcpy(dst, pat, 4); |
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dst += 4; |
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} |
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break; |
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case 8: |
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while (samples--) { |
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memcpy(dst, pat, 8); |
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dst += 8; |
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} |
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break; |
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} |
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#endif |
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return 0; |
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} |
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EXPORT_SYMBOL(snd_pcm_format_set_silence); |
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|
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/** |
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* snd_pcm_hw_limit_rates - determine rate_min/rate_max fields |
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* @hw: the pcm hw instance |
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* |
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* Determines the rate_min and rate_max fields from the rates bits of |
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* the given hw. |
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* |
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* Return: Zero if successful. |
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*/ |
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int snd_pcm_hw_limit_rates(struct snd_pcm_hardware *hw) |
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{ |
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int i; |
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for (i = 0; i < (int)snd_pcm_known_rates.count; i++) { |
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if (hw->rates & (1 << i)) { |
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hw->rate_min = snd_pcm_known_rates.list[i]; |
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break; |
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} |
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} |
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for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) { |
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if (hw->rates & (1 << i)) { |
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hw->rate_max = snd_pcm_known_rates.list[i]; |
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break; |
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} |
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} |
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return 0; |
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} |
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EXPORT_SYMBOL(snd_pcm_hw_limit_rates); |
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|
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/** |
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* snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit |
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* @rate: the sample rate to convert |
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* |
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* Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or |
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* SNDRV_PCM_RATE_KNOT for an unknown rate. |
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*/ |
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unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate) |
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{ |
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unsigned int i; |
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|
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for (i = 0; i < snd_pcm_known_rates.count; i++) |
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if (snd_pcm_known_rates.list[i] == rate) |
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return 1u << i; |
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return SNDRV_PCM_RATE_KNOT; |
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} |
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EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit); |
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|
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/** |
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* snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate |
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* @rate_bit: the rate bit to convert |
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* |
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* Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag |
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* or 0 for an unknown rate bit. |
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*/ |
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unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit) |
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{ |
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unsigned int i; |
|
|
|
for (i = 0; i < snd_pcm_known_rates.count; i++) |
|
if ((1u << i) == rate_bit) |
|
return snd_pcm_known_rates.list[i]; |
|
return 0; |
|
} |
|
EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate); |
|
|
|
static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates) |
|
{ |
|
if (rates & SNDRV_PCM_RATE_CONTINUOUS) |
|
return SNDRV_PCM_RATE_CONTINUOUS; |
|
else if (rates & SNDRV_PCM_RATE_KNOT) |
|
return SNDRV_PCM_RATE_KNOT; |
|
return rates; |
|
} |
|
|
|
/** |
|
* snd_pcm_rate_mask_intersect - computes the intersection between two rate masks |
|
* @rates_a: The first rate mask |
|
* @rates_b: The second rate mask |
|
* |
|
* This function computes the rates that are supported by both rate masks passed |
|
* to the function. It will take care of the special handling of |
|
* SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT. |
|
* |
|
* Return: A rate mask containing the rates that are supported by both rates_a |
|
* and rates_b. |
|
*/ |
|
unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a, |
|
unsigned int rates_b) |
|
{ |
|
rates_a = snd_pcm_rate_mask_sanitize(rates_a); |
|
rates_b = snd_pcm_rate_mask_sanitize(rates_b); |
|
|
|
if (rates_a & SNDRV_PCM_RATE_CONTINUOUS) |
|
return rates_b; |
|
else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS) |
|
return rates_a; |
|
else if (rates_a & SNDRV_PCM_RATE_KNOT) |
|
return rates_b; |
|
else if (rates_b & SNDRV_PCM_RATE_KNOT) |
|
return rates_a; |
|
return rates_a & rates_b; |
|
} |
|
EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect); |
|
|
|
/** |
|
* snd_pcm_rate_range_to_bits - converts rate range to SNDRV_PCM_RATE_xxx bit |
|
* @rate_min: the minimum sample rate |
|
* @rate_max: the maximum sample rate |
|
* |
|
* This function has an implicit assumption: the rates in the given range have |
|
* only the pre-defined rates like 44100 or 16000. |
|
* |
|
* Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate range, |
|
* or SNDRV_PCM_RATE_KNOT for an unknown range. |
|
*/ |
|
unsigned int snd_pcm_rate_range_to_bits(unsigned int rate_min, |
|
unsigned int rate_max) |
|
{ |
|
unsigned int rates = 0; |
|
int i; |
|
|
|
for (i = 0; i < snd_pcm_known_rates.count; i++) { |
|
if (snd_pcm_known_rates.list[i] >= rate_min |
|
&& snd_pcm_known_rates.list[i] <= rate_max) |
|
rates |= 1 << i; |
|
} |
|
|
|
if (!rates) |
|
rates = SNDRV_PCM_RATE_KNOT; |
|
|
|
return rates; |
|
} |
|
EXPORT_SYMBOL_GPL(snd_pcm_rate_range_to_bits);
|
|
|