diff options
Diffstat (limited to 'sound/core/pcm_misc.c')
-rw-r--r-- | sound/core/pcm_misc.c | 490 |
1 files changed, 490 insertions, 0 deletions
diff --git a/sound/core/pcm_misc.c b/sound/core/pcm_misc.c new file mode 100644 index 00000000..9c9eff9a --- /dev/null +++ b/sound/core/pcm_misc.c @@ -0,0 +1,490 @@ +/* + * PCM Interface - misc routines + * Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz> + * + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the GNU Library General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include <linux/time.h> +#include <linux/export.h> +#include <sound/core.h> +#include <sound/pcm.h> +#define SND_PCM_FORMAT_UNKNOWN (-1) + +/* NOTE: "signed" prefix must be given below since the default char is + * unsigned on some architectures! + */ +struct pcm_format_data { + unsigned char width; /* bit width */ + unsigned char phys; /* physical bit width */ + signed char le; /* 0 = big-endian, 1 = little-endian, -1 = others */ + signed char signd; /* 0 = unsigned, 1 = signed, -1 = others */ + unsigned char silence[8]; /* silence data to fill */ +}; + +/* we do lots of calculations on snd_pcm_format_t; shut up sparse */ +#define INT __force int + +static struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = { + [SNDRV_PCM_FORMAT_S8] = { + .width = 8, .phys = 8, .le = -1, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_U8] = { + .width = 8, .phys = 8, .le = -1, .signd = 0, + .silence = { 0x80 }, + }, + [SNDRV_PCM_FORMAT_S16_LE] = { + .width = 16, .phys = 16, .le = 1, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_S16_BE] = { + .width = 16, .phys = 16, .le = 0, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_U16_LE] = { + .width = 16, .phys = 16, .le = 1, .signd = 0, + .silence = { 0x00, 0x80 }, + }, + [SNDRV_PCM_FORMAT_U16_BE] = { + .width = 16, .phys = 16, .le = 0, .signd = 0, + .silence = { 0x80, 0x00 }, + }, + [SNDRV_PCM_FORMAT_S24_LE] = { + .width = 24, .phys = 32, .le = 1, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_S24_BE] = { + .width = 24, .phys = 32, .le = 0, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_U24_LE] = { + .width = 24, .phys = 32, .le = 1, .signd = 0, + .silence = { 0x00, 0x00, 0x80 }, + }, + [SNDRV_PCM_FORMAT_U24_BE] = { + .width = 24, .phys = 32, .le = 0, .signd = 0, + .silence = { 0x00, 0x80, 0x00, 0x00 }, + }, + [SNDRV_PCM_FORMAT_S32_LE] = { + .width = 32, .phys = 32, .le = 1, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_S32_BE] = { + .width = 32, .phys = 32, .le = 0, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_U32_LE] = { + .width = 32, .phys = 32, .le = 1, .signd = 0, + .silence = { 0x00, 0x00, 0x00, 0x80 }, + }, + [SNDRV_PCM_FORMAT_U32_BE] = { + .width = 32, .phys = 32, .le = 0, .signd = 0, + .silence = { 0x80, 0x00, 0x00, 0x00 }, + }, + [SNDRV_PCM_FORMAT_FLOAT_LE] = { + .width = 32, .phys = 32, .le = 1, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_FLOAT_BE] = { + .width = 32, .phys = 32, .le = 0, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_FLOAT64_LE] = { + .width = 64, .phys = 64, .le = 1, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_FLOAT64_BE] = { + .width = 64, .phys = 64, .le = 0, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = { + .width = 32, .phys = 32, .le = 1, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = { + .width = 32, .phys = 32, .le = 0, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_MU_LAW] = { + .width = 8, .phys = 8, .le = -1, .signd = -1, + .silence = { 0x7f }, + }, + [SNDRV_PCM_FORMAT_A_LAW] = { + .width = 8, .phys = 8, .le = -1, .signd = -1, + .silence = { 0x55 }, + }, + [SNDRV_PCM_FORMAT_IMA_ADPCM] = { + .width = 4, .phys = 4, .le = -1, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_G723_24] = { + .width = 3, .phys = 3, .le = -1, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_G723_40] = { + .width = 5, .phys = 5, .le = -1, .signd = -1, + .silence = {}, + }, + /* FIXME: the following three formats are not defined properly yet */ + [SNDRV_PCM_FORMAT_MPEG] = { + .le = -1, .signd = -1, + }, + [SNDRV_PCM_FORMAT_GSM] = { + .le = -1, .signd = -1, + }, + [SNDRV_PCM_FORMAT_SPECIAL] = { + .le = -1, .signd = -1, + }, + [SNDRV_PCM_FORMAT_S24_3LE] = { + .width = 24, .phys = 24, .le = 1, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_S24_3BE] = { + .width = 24, .phys = 24, .le = 0, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_U24_3LE] = { + .width = 24, .phys = 24, .le = 1, .signd = 0, + .silence = { 0x00, 0x00, 0x80 }, + }, + [SNDRV_PCM_FORMAT_U24_3BE] = { + .width = 24, .phys = 24, .le = 0, .signd = 0, + .silence = { 0x80, 0x00, 0x00 }, + }, + [SNDRV_PCM_FORMAT_S20_3LE] = { + .width = 20, .phys = 24, .le = 1, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_S20_3BE] = { + .width = 20, .phys = 24, .le = 0, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_U20_3LE] = { + .width = 20, .phys = 24, .le = 1, .signd = 0, + .silence = { 0x00, 0x00, 0x08 }, + }, + [SNDRV_PCM_FORMAT_U20_3BE] = { + .width = 20, .phys = 24, .le = 0, .signd = 0, + .silence = { 0x08, 0x00, 0x00 }, + }, + [SNDRV_PCM_FORMAT_S18_3LE] = { + .width = 18, .phys = 24, .le = 1, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_S18_3BE] = { + .width = 18, .phys = 24, .le = 0, .signd = 1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_U18_3LE] = { + .width = 18, .phys = 24, .le = 1, .signd = 0, + .silence = { 0x00, 0x00, 0x02 }, + }, + [SNDRV_PCM_FORMAT_U18_3BE] = { + .width = 18, .phys = 24, .le = 0, .signd = 0, + .silence = { 0x02, 0x00, 0x00 }, + }, + [SNDRV_PCM_FORMAT_G723_24_1B] = { + .width = 3, .phys = 8, .le = -1, .signd = -1, + .silence = {}, + }, + [SNDRV_PCM_FORMAT_G723_40_1B] = { + .width = 5, .phys = 8, .le = -1, .signd = -1, + .silence = {}, + }, +}; + + +/** + * snd_pcm_format_signed - Check the PCM format is signed linear + * @format: the format to check + * + * Returns 1 if the given PCM format is signed linear, 0 if unsigned + * linear, and a negative error code for non-linear formats. + */ +int snd_pcm_format_signed(snd_pcm_format_t format) +{ + int val; + if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) + return -EINVAL; + if ((val = pcm_formats[(INT)format].signd) < 0) + return -EINVAL; + return val; +} + +EXPORT_SYMBOL(snd_pcm_format_signed); + +/** + * snd_pcm_format_unsigned - Check the PCM format is unsigned linear + * @format: the format to check + * + * Returns 1 if the given PCM format is unsigned linear, 0 if signed + * linear, and a negative error code for non-linear formats. + */ +int snd_pcm_format_unsigned(snd_pcm_format_t format) +{ + int val; + + val = snd_pcm_format_signed(format); + if (val < 0) + return val; + return !val; +} + +EXPORT_SYMBOL(snd_pcm_format_unsigned); + +/** + * snd_pcm_format_linear - Check the PCM format is linear + * @format: the format to check + * + * Returns 1 if the given PCM format is linear, 0 if not. + */ +int snd_pcm_format_linear(snd_pcm_format_t format) +{ + return snd_pcm_format_signed(format) >= 0; +} + +EXPORT_SYMBOL(snd_pcm_format_linear); + +/** + * snd_pcm_format_little_endian - Check the PCM format is little-endian + * @format: the format to check + * + * Returns 1 if the given PCM format is little-endian, 0 if + * big-endian, or a negative error code if endian not specified. + */ +int snd_pcm_format_little_endian(snd_pcm_format_t format) +{ + int val; + if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) + return -EINVAL; + if ((val = pcm_formats[(INT)format].le) < 0) + return -EINVAL; + return val; +} + +EXPORT_SYMBOL(snd_pcm_format_little_endian); + +/** + * snd_pcm_format_big_endian - Check the PCM format is big-endian + * @format: the format to check + * + * Returns 1 if the given PCM format is big-endian, 0 if + * little-endian, or a negative error code if endian not specified. + */ +int snd_pcm_format_big_endian(snd_pcm_format_t format) +{ + int val; + + val = snd_pcm_format_little_endian(format); + if (val < 0) + return val; + return !val; +} + +EXPORT_SYMBOL(snd_pcm_format_big_endian); + +/** + * snd_pcm_format_width - return the bit-width of the format + * @format: the format to check + * + * Returns the bit-width of the format, or a negative error code + * if unknown format. + */ +int snd_pcm_format_width(snd_pcm_format_t format) +{ + int val; + if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) + return -EINVAL; + if ((val = pcm_formats[(INT)format].width) == 0) + return -EINVAL; + return val; +} + +EXPORT_SYMBOL(snd_pcm_format_width); + +/** + * snd_pcm_format_physical_width - return the physical bit-width of the format + * @format: the format to check + * + * Returns the physical bit-width of the format, or a negative error code + * if unknown format. + */ +int snd_pcm_format_physical_width(snd_pcm_format_t format) +{ + int val; + if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) + return -EINVAL; + if ((val = pcm_formats[(INT)format].phys) == 0) + return -EINVAL; + return val; +} + +EXPORT_SYMBOL(snd_pcm_format_physical_width); + +/** + * snd_pcm_format_size - return the byte size of samples on the given format + * @format: the format to check + * @samples: sampling rate + * + * Returns the byte size of the given samples for the format, or a + * negative error code if unknown format. + */ +ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples) +{ + int phys_width = snd_pcm_format_physical_width(format); + if (phys_width < 0) + return -EINVAL; + return samples * phys_width / 8; +} + +EXPORT_SYMBOL(snd_pcm_format_size); + +/** + * snd_pcm_format_silence_64 - return the silent data in 8 bytes array + * @format: the format to check + * + * Returns the format pattern to fill or NULL if error. + */ +const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format) +{ + if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) + return NULL; + if (! pcm_formats[(INT)format].phys) + return NULL; + return pcm_formats[(INT)format].silence; +} + +EXPORT_SYMBOL(snd_pcm_format_silence_64); + +/** + * snd_pcm_format_set_silence - set the silence data on the buffer + * @format: the PCM format + * @data: the buffer pointer + * @samples: the number of samples to set silence + * + * Sets the silence data on the buffer for the given samples. + * + * Returns zero if successful, or a negative error code on failure. + */ +int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples) +{ + int width; + unsigned char *dst, *pat; + + if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST) + return -EINVAL; + if (samples == 0) + return 0; + width = pcm_formats[(INT)format].phys; /* physical width */ + pat = pcm_formats[(INT)format].silence; + if (! width) + return -EINVAL; + /* signed or 1 byte data */ + if (pcm_formats[(INT)format].signd == 1 || width <= 8) { + unsigned int bytes = samples * width / 8; + memset(data, *pat, bytes); + return 0; + } + /* non-zero samples, fill using a loop */ + width /= 8; + dst = data; +#if 0 + while (samples--) { + memcpy(dst, pat, width); + dst += width; + } +#else + /* a bit optimization for constant width */ + switch (width) { + case 2: + while (samples--) { + memcpy(dst, pat, 2); + dst += 2; + } + break; + case 3: + while (samples--) { + memcpy(dst, pat, 3); + dst += 3; + } + break; + case 4: + while (samples--) { + memcpy(dst, pat, 4); + dst += 4; + } + break; + case 8: + while (samples--) { + memcpy(dst, pat, 8); + dst += 8; + } + break; + } +#endif + return 0; +} + +EXPORT_SYMBOL(snd_pcm_format_set_silence); + +/** + * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields + * @runtime: the runtime instance + * + * Determines the rate_min and rate_max fields from the rates bits of + * the given runtime->hw. + * + * Returns zero if successful. + */ +int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime) +{ + int i; + for (i = 0; i < (int)snd_pcm_known_rates.count; i++) { + if (runtime->hw.rates & (1 << i)) { + runtime->hw.rate_min = snd_pcm_known_rates.list[i]; + break; + } + } + for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) { + if (runtime->hw.rates & (1 << i)) { + runtime->hw.rate_max = snd_pcm_known_rates.list[i]; + break; + } + } + return 0; +} + +EXPORT_SYMBOL(snd_pcm_limit_hw_rates); + +/** + * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit + * @rate: the sample rate to convert + * + * Returns the SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or + * SNDRV_PCM_RATE_KNOT for an unknown rate. + */ +unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate) +{ + unsigned int i; + + for (i = 0; i < snd_pcm_known_rates.count; i++) + if (snd_pcm_known_rates.list[i] == rate) + return 1u << i; + return SNDRV_PCM_RATE_KNOT; +} +EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit); |