2 * PCM Interface - misc routines
3 * Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz>
6 * This library is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU Library General Public License as
8 * published by the Free Software Foundation; either version 2 of
9 * the License, or (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/time.h>
23 #include <linux/export.h>
24 #include <sound/core.h>
25 #include <sound/pcm.h>
27 #include "pcm_local.h"
29 #define SND_PCM_FORMAT_UNKNOWN (-1)
31 /* NOTE: "signed" prefix must be given below since the default char is
32 * unsigned on some architectures!
34 struct pcm_format_data {
35 unsigned char width; /* bit width */
36 unsigned char phys; /* physical bit width */
37 signed char le; /* 0 = big-endian, 1 = little-endian, -1 = others */
38 signed char signd; /* 0 = unsigned, 1 = signed, -1 = others */
39 unsigned char silence[8]; /* silence data to fill */
42 /* we do lots of calculations on snd_pcm_format_t; shut up sparse */
43 #define INT __force int
45 static bool valid_format(snd_pcm_format_t format)
47 return (INT)format >= 0 && (INT)format <= (INT)SNDRV_PCM_FORMAT_LAST;
50 static const struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = {
51 [SNDRV_PCM_FORMAT_S8] = {
52 .width = 8, .phys = 8, .le = -1, .signd = 1,
55 [SNDRV_PCM_FORMAT_U8] = {
56 .width = 8, .phys = 8, .le = -1, .signd = 0,
59 [SNDRV_PCM_FORMAT_S16_LE] = {
60 .width = 16, .phys = 16, .le = 1, .signd = 1,
63 [SNDRV_PCM_FORMAT_S16_BE] = {
64 .width = 16, .phys = 16, .le = 0, .signd = 1,
67 [SNDRV_PCM_FORMAT_U16_LE] = {
68 .width = 16, .phys = 16, .le = 1, .signd = 0,
69 .silence = { 0x00, 0x80 },
71 [SNDRV_PCM_FORMAT_U16_BE] = {
72 .width = 16, .phys = 16, .le = 0, .signd = 0,
73 .silence = { 0x80, 0x00 },
75 [SNDRV_PCM_FORMAT_S24_LE] = {
76 .width = 24, .phys = 32, .le = 1, .signd = 1,
79 [SNDRV_PCM_FORMAT_S24_BE] = {
80 .width = 24, .phys = 32, .le = 0, .signd = 1,
83 [SNDRV_PCM_FORMAT_U24_LE] = {
84 .width = 24, .phys = 32, .le = 1, .signd = 0,
85 .silence = { 0x00, 0x00, 0x80 },
87 [SNDRV_PCM_FORMAT_U24_BE] = {
88 .width = 24, .phys = 32, .le = 0, .signd = 0,
89 .silence = { 0x00, 0x80, 0x00, 0x00 },
91 [SNDRV_PCM_FORMAT_S32_LE] = {
92 .width = 32, .phys = 32, .le = 1, .signd = 1,
95 [SNDRV_PCM_FORMAT_S32_BE] = {
96 .width = 32, .phys = 32, .le = 0, .signd = 1,
99 [SNDRV_PCM_FORMAT_U32_LE] = {
100 .width = 32, .phys = 32, .le = 1, .signd = 0,
101 .silence = { 0x00, 0x00, 0x00, 0x80 },
103 [SNDRV_PCM_FORMAT_U32_BE] = {
104 .width = 32, .phys = 32, .le = 0, .signd = 0,
105 .silence = { 0x80, 0x00, 0x00, 0x00 },
107 [SNDRV_PCM_FORMAT_FLOAT_LE] = {
108 .width = 32, .phys = 32, .le = 1, .signd = -1,
111 [SNDRV_PCM_FORMAT_FLOAT_BE] = {
112 .width = 32, .phys = 32, .le = 0, .signd = -1,
115 [SNDRV_PCM_FORMAT_FLOAT64_LE] = {
116 .width = 64, .phys = 64, .le = 1, .signd = -1,
119 [SNDRV_PCM_FORMAT_FLOAT64_BE] = {
120 .width = 64, .phys = 64, .le = 0, .signd = -1,
123 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
124 .width = 32, .phys = 32, .le = 1, .signd = -1,
127 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
128 .width = 32, .phys = 32, .le = 0, .signd = -1,
131 [SNDRV_PCM_FORMAT_MU_LAW] = {
132 .width = 8, .phys = 8, .le = -1, .signd = -1,
135 [SNDRV_PCM_FORMAT_A_LAW] = {
136 .width = 8, .phys = 8, .le = -1, .signd = -1,
139 [SNDRV_PCM_FORMAT_IMA_ADPCM] = {
140 .width = 4, .phys = 4, .le = -1, .signd = -1,
143 [SNDRV_PCM_FORMAT_G723_24] = {
144 .width = 3, .phys = 3, .le = -1, .signd = -1,
147 [SNDRV_PCM_FORMAT_G723_40] = {
148 .width = 5, .phys = 5, .le = -1, .signd = -1,
151 [SNDRV_PCM_FORMAT_DSD_U8] = {
152 .width = 8, .phys = 8, .le = 1, .signd = 0,
155 [SNDRV_PCM_FORMAT_DSD_U16_LE] = {
156 .width = 16, .phys = 16, .le = 1, .signd = 0,
157 .silence = { 0x69, 0x69 },
159 [SNDRV_PCM_FORMAT_DSD_U32_LE] = {
160 .width = 32, .phys = 32, .le = 1, .signd = 0,
161 .silence = { 0x69, 0x69, 0x69, 0x69 },
163 [SNDRV_PCM_FORMAT_DSD_U16_BE] = {
164 .width = 16, .phys = 16, .le = 0, .signd = 0,
165 .silence = { 0x69, 0x69 },
167 [SNDRV_PCM_FORMAT_DSD_U32_BE] = {
168 .width = 32, .phys = 32, .le = 0, .signd = 0,
169 .silence = { 0x69, 0x69, 0x69, 0x69 },
171 /* FIXME: the following two formats are not defined properly yet */
172 [SNDRV_PCM_FORMAT_MPEG] = {
173 .le = -1, .signd = -1,
175 [SNDRV_PCM_FORMAT_GSM] = {
176 .le = -1, .signd = -1,
178 [SNDRV_PCM_FORMAT_S20_LE] = {
179 .width = 20, .phys = 32, .le = 1, .signd = 1,
182 [SNDRV_PCM_FORMAT_S20_BE] = {
183 .width = 20, .phys = 32, .le = 0, .signd = 1,
186 [SNDRV_PCM_FORMAT_U20_LE] = {
187 .width = 20, .phys = 32, .le = 1, .signd = 0,
188 .silence = { 0x00, 0x00, 0x08, 0x00 },
190 [SNDRV_PCM_FORMAT_U20_BE] = {
191 .width = 20, .phys = 32, .le = 0, .signd = 0,
192 .silence = { 0x00, 0x08, 0x00, 0x00 },
194 /* FIXME: the following format is not defined properly yet */
195 [SNDRV_PCM_FORMAT_SPECIAL] = {
196 .le = -1, .signd = -1,
198 [SNDRV_PCM_FORMAT_S24_3LE] = {
199 .width = 24, .phys = 24, .le = 1, .signd = 1,
202 [SNDRV_PCM_FORMAT_S24_3BE] = {
203 .width = 24, .phys = 24, .le = 0, .signd = 1,
206 [SNDRV_PCM_FORMAT_U24_3LE] = {
207 .width = 24, .phys = 24, .le = 1, .signd = 0,
208 .silence = { 0x00, 0x00, 0x80 },
210 [SNDRV_PCM_FORMAT_U24_3BE] = {
211 .width = 24, .phys = 24, .le = 0, .signd = 0,
212 .silence = { 0x80, 0x00, 0x00 },
214 [SNDRV_PCM_FORMAT_S20_3LE] = {
215 .width = 20, .phys = 24, .le = 1, .signd = 1,
218 [SNDRV_PCM_FORMAT_S20_3BE] = {
219 .width = 20, .phys = 24, .le = 0, .signd = 1,
222 [SNDRV_PCM_FORMAT_U20_3LE] = {
223 .width = 20, .phys = 24, .le = 1, .signd = 0,
224 .silence = { 0x00, 0x00, 0x08 },
226 [SNDRV_PCM_FORMAT_U20_3BE] = {
227 .width = 20, .phys = 24, .le = 0, .signd = 0,
228 .silence = { 0x08, 0x00, 0x00 },
230 [SNDRV_PCM_FORMAT_S18_3LE] = {
231 .width = 18, .phys = 24, .le = 1, .signd = 1,
234 [SNDRV_PCM_FORMAT_S18_3BE] = {
235 .width = 18, .phys = 24, .le = 0, .signd = 1,
238 [SNDRV_PCM_FORMAT_U18_3LE] = {
239 .width = 18, .phys = 24, .le = 1, .signd = 0,
240 .silence = { 0x00, 0x00, 0x02 },
242 [SNDRV_PCM_FORMAT_U18_3BE] = {
243 .width = 18, .phys = 24, .le = 0, .signd = 0,
244 .silence = { 0x02, 0x00, 0x00 },
246 [SNDRV_PCM_FORMAT_G723_24_1B] = {
247 .width = 3, .phys = 8, .le = -1, .signd = -1,
250 [SNDRV_PCM_FORMAT_G723_40_1B] = {
251 .width = 5, .phys = 8, .le = -1, .signd = -1,
258 * snd_pcm_format_signed - Check the PCM format is signed linear
259 * @format: the format to check
261 * Return: 1 if the given PCM format is signed linear, 0 if unsigned
262 * linear, and a negative error code for non-linear formats.
264 int snd_pcm_format_signed(snd_pcm_format_t format)
267 if (!valid_format(format))
269 if ((val = pcm_formats[(INT)format].signd) < 0)
273 EXPORT_SYMBOL(snd_pcm_format_signed);
276 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
277 * @format: the format to check
279 * Return: 1 if the given PCM format is unsigned linear, 0 if signed
280 * linear, and a negative error code for non-linear formats.
282 int snd_pcm_format_unsigned(snd_pcm_format_t format)
286 val = snd_pcm_format_signed(format);
291 EXPORT_SYMBOL(snd_pcm_format_unsigned);
294 * snd_pcm_format_linear - Check the PCM format is linear
295 * @format: the format to check
297 * Return: 1 if the given PCM format is linear, 0 if not.
299 int snd_pcm_format_linear(snd_pcm_format_t format)
301 return snd_pcm_format_signed(format) >= 0;
303 EXPORT_SYMBOL(snd_pcm_format_linear);
306 * snd_pcm_format_little_endian - Check the PCM format is little-endian
307 * @format: the format to check
309 * Return: 1 if the given PCM format is little-endian, 0 if
310 * big-endian, or a negative error code if endian not specified.
312 int snd_pcm_format_little_endian(snd_pcm_format_t format)
315 if (!valid_format(format))
317 if ((val = pcm_formats[(INT)format].le) < 0)
321 EXPORT_SYMBOL(snd_pcm_format_little_endian);
324 * snd_pcm_format_big_endian - Check the PCM format is big-endian
325 * @format: the format to check
327 * Return: 1 if the given PCM format is big-endian, 0 if
328 * little-endian, or a negative error code if endian not specified.
330 int snd_pcm_format_big_endian(snd_pcm_format_t format)
334 val = snd_pcm_format_little_endian(format);
339 EXPORT_SYMBOL(snd_pcm_format_big_endian);
342 * snd_pcm_format_width - return the bit-width of the format
343 * @format: the format to check
345 * Return: The bit-width of the format, or a negative error code
348 int snd_pcm_format_width(snd_pcm_format_t format)
351 if (!valid_format(format))
353 if ((val = pcm_formats[(INT)format].width) == 0)
357 EXPORT_SYMBOL(snd_pcm_format_width);
360 * snd_pcm_format_physical_width - return the physical bit-width of the format
361 * @format: the format to check
363 * Return: The physical bit-width of the format, or a negative error code
366 int snd_pcm_format_physical_width(snd_pcm_format_t format)
369 if (!valid_format(format))
371 if ((val = pcm_formats[(INT)format].phys) == 0)
375 EXPORT_SYMBOL(snd_pcm_format_physical_width);
378 * snd_pcm_format_size - return the byte size of samples on the given format
379 * @format: the format to check
380 * @samples: sampling rate
382 * Return: The byte size of the given samples for the format, or a
383 * negative error code if unknown format.
385 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
387 int phys_width = snd_pcm_format_physical_width(format);
390 return samples * phys_width / 8;
392 EXPORT_SYMBOL(snd_pcm_format_size);
395 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
396 * @format: the format to check
398 * Return: The format pattern to fill or %NULL if error.
400 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
402 if (!valid_format(format))
404 if (! pcm_formats[(INT)format].phys)
406 return pcm_formats[(INT)format].silence;
408 EXPORT_SYMBOL(snd_pcm_format_silence_64);
411 * snd_pcm_format_set_silence - set the silence data on the buffer
412 * @format: the PCM format
413 * @data: the buffer pointer
414 * @samples: the number of samples to set silence
416 * Sets the silence data on the buffer for the given samples.
418 * Return: Zero if successful, or a negative error code on failure.
420 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
424 const unsigned char *pat;
426 if (!valid_format(format))
430 width = pcm_formats[(INT)format].phys; /* physical width */
431 pat = pcm_formats[(INT)format].silence;
434 /* signed or 1 byte data */
435 if (pcm_formats[(INT)format].signd == 1 || width <= 8) {
436 unsigned int bytes = samples * width / 8;
437 memset(data, *pat, bytes);
440 /* non-zero samples, fill using a loop */
445 memcpy(dst, pat, width);
449 /* a bit optimization for constant width */
479 EXPORT_SYMBOL(snd_pcm_format_set_silence);
482 * snd_pcm_hw_limit_rates - determine rate_min/rate_max fields
483 * @hw: the pcm hw instance
485 * Determines the rate_min and rate_max fields from the rates bits of
488 * Return: Zero if successful.
490 int snd_pcm_hw_limit_rates(struct snd_pcm_hardware *hw)
493 for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
494 if (hw->rates & (1 << i)) {
495 hw->rate_min = snd_pcm_known_rates.list[i];
499 for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
500 if (hw->rates & (1 << i)) {
501 hw->rate_max = snd_pcm_known_rates.list[i];
507 EXPORT_SYMBOL(snd_pcm_hw_limit_rates);
510 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
511 * @rate: the sample rate to convert
513 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
514 * SNDRV_PCM_RATE_KNOT for an unknown rate.
516 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
520 for (i = 0; i < snd_pcm_known_rates.count; i++)
521 if (snd_pcm_known_rates.list[i] == rate)
523 return SNDRV_PCM_RATE_KNOT;
525 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);
528 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate
529 * @rate_bit: the rate bit to convert
531 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag
532 * or 0 for an unknown rate bit.
534 unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit)
538 for (i = 0; i < snd_pcm_known_rates.count; i++)
539 if ((1u << i) == rate_bit)
540 return snd_pcm_known_rates.list[i];
543 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate);
545 static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates)
547 if (rates & SNDRV_PCM_RATE_CONTINUOUS)
548 return SNDRV_PCM_RATE_CONTINUOUS;
549 else if (rates & SNDRV_PCM_RATE_KNOT)
550 return SNDRV_PCM_RATE_KNOT;
555 * snd_pcm_rate_mask_intersect - computes the intersection between two rate masks
556 * @rates_a: The first rate mask
557 * @rates_b: The second rate mask
559 * This function computes the rates that are supported by both rate masks passed
560 * to the function. It will take care of the special handling of
561 * SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT.
563 * Return: A rate mask containing the rates that are supported by both rates_a
566 unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a,
567 unsigned int rates_b)
569 rates_a = snd_pcm_rate_mask_sanitize(rates_a);
570 rates_b = snd_pcm_rate_mask_sanitize(rates_b);
572 if (rates_a & SNDRV_PCM_RATE_CONTINUOUS)
574 else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS)
576 else if (rates_a & SNDRV_PCM_RATE_KNOT)
578 else if (rates_b & SNDRV_PCM_RATE_KNOT)
580 return rates_a & rates_b;
582 EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect);
585 * snd_pcm_rate_range_to_bits - converts rate range to SNDRV_PCM_RATE_xxx bit
586 * @rate_min: the minimum sample rate
587 * @rate_max: the maximum sample rate
589 * This function has an implicit assumption: the rates in the given range have
590 * only the pre-defined rates like 44100 or 16000.
592 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate range,
593 * or SNDRV_PCM_RATE_KNOT for an unknown range.
595 unsigned int snd_pcm_rate_range_to_bits(unsigned int rate_min,
596 unsigned int rate_max)
598 unsigned int rates = 0;
601 for (i = 0; i < snd_pcm_known_rates.count; i++) {
602 if (snd_pcm_known_rates.list[i] >= rate_min
603 && snd_pcm_known_rates.list[i] <= rate_max)
608 rates = SNDRV_PCM_RATE_KNOT;
612 EXPORT_SYMBOL_GPL(snd_pcm_rate_range_to_bits);