/* * 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 <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 */ }; static struct pcm_format_data pcm_formats[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 = {}, }, /* 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 }, }, }; /** * 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 (format < 0 || format > SNDRV_PCM_FORMAT_LAST) return -EINVAL; if ((val = pcm_formats[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 (format < 0 || format > SNDRV_PCM_FORMAT_LAST) return -EINVAL; if ((val = pcm_formats[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 (format < 0 || format > SNDRV_PCM_FORMAT_LAST) return -EINVAL; if ((val = pcm_formats[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 (format < 0 || format > SNDRV_PCM_FORMAT_LAST) return -EINVAL; if ((val = pcm_formats[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 (format < 0 || format > SNDRV_PCM_FORMAT_LAST) return NULL; if (! pcm_formats[format].phys) return NULL; return pcm_formats[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 (format < 0 || format > SNDRV_PCM_FORMAT_LAST) return -EINVAL; if (samples == 0) return 0; width = pcm_formats[format].phys; /* physical width */ pat = pcm_formats[format].silence; if (! width) return -EINVAL; /* signed or 1 byte data */ if (pcm_formats[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);