1 /*
2 * PCM Interface - misc routines
3 * Copyright (c) 1998 by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
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.
10 *
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.
15 *
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
19 *
20 */
21
22 #include <linux/time.h>
23 #include <linux/export.h>
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26
27 #include "pcm_local.h"
28
29 #define SND_PCM_FORMAT_UNKNOWN (-1)
30
31 /* NOTE: "signed" prefix must be given below since the default char is
32 * unsigned on some architectures!
33 */
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 */
40 };
41
42 /* we do lots of calculations on snd_pcm_format_t; shut up sparse */
43 #define INT __force int
44
45 static struct pcm_format_data pcm_formats[(INT)SNDRV_PCM_FORMAT_LAST+1] = {
46 [SNDRV_PCM_FORMAT_S8] = {
47 .width = 8, .phys = 8, .le = -1, .signd = 1,
48 .silence = {},
49 },
50 [SNDRV_PCM_FORMAT_U8] = {
51 .width = 8, .phys = 8, .le = -1, .signd = 0,
52 .silence = { 0x80 },
53 },
54 [SNDRV_PCM_FORMAT_S16_LE] = {
55 .width = 16, .phys = 16, .le = 1, .signd = 1,
56 .silence = {},
57 },
58 [SNDRV_PCM_FORMAT_S16_BE] = {
59 .width = 16, .phys = 16, .le = 0, .signd = 1,
60 .silence = {},
61 },
62 [SNDRV_PCM_FORMAT_U16_LE] = {
63 .width = 16, .phys = 16, .le = 1, .signd = 0,
64 .silence = { 0x00, 0x80 },
65 },
66 [SNDRV_PCM_FORMAT_U16_BE] = {
67 .width = 16, .phys = 16, .le = 0, .signd = 0,
68 .silence = { 0x80, 0x00 },
69 },
70 [SNDRV_PCM_FORMAT_S24_LE] = {
71 .width = 24, .phys = 32, .le = 1, .signd = 1,
72 .silence = {},
73 },
74 [SNDRV_PCM_FORMAT_S24_BE] = {
75 .width = 24, .phys = 32, .le = 0, .signd = 1,
76 .silence = {},
77 },
78 [SNDRV_PCM_FORMAT_U24_LE] = {
79 .width = 24, .phys = 32, .le = 1, .signd = 0,
80 .silence = { 0x00, 0x00, 0x80 },
81 },
82 [SNDRV_PCM_FORMAT_U24_BE] = {
83 .width = 24, .phys = 32, .le = 0, .signd = 0,
84 .silence = { 0x00, 0x80, 0x00, 0x00 },
85 },
86 [SNDRV_PCM_FORMAT_S32_LE] = {
87 .width = 32, .phys = 32, .le = 1, .signd = 1,
88 .silence = {},
89 },
90 [SNDRV_PCM_FORMAT_S32_BE] = {
91 .width = 32, .phys = 32, .le = 0, .signd = 1,
92 .silence = {},
93 },
94 [SNDRV_PCM_FORMAT_U32_LE] = {
95 .width = 32, .phys = 32, .le = 1, .signd = 0,
96 .silence = { 0x00, 0x00, 0x00, 0x80 },
97 },
98 [SNDRV_PCM_FORMAT_U32_BE] = {
99 .width = 32, .phys = 32, .le = 0, .signd = 0,
100 .silence = { 0x80, 0x00, 0x00, 0x00 },
101 },
102 [SNDRV_PCM_FORMAT_FLOAT_LE] = {
103 .width = 32, .phys = 32, .le = 1, .signd = -1,
104 .silence = {},
105 },
106 [SNDRV_PCM_FORMAT_FLOAT_BE] = {
107 .width = 32, .phys = 32, .le = 0, .signd = -1,
108 .silence = {},
109 },
110 [SNDRV_PCM_FORMAT_FLOAT64_LE] = {
111 .width = 64, .phys = 64, .le = 1, .signd = -1,
112 .silence = {},
113 },
114 [SNDRV_PCM_FORMAT_FLOAT64_BE] = {
115 .width = 64, .phys = 64, .le = 0, .signd = -1,
116 .silence = {},
117 },
118 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
119 .width = 32, .phys = 32, .le = 1, .signd = -1,
120 .silence = {},
121 },
122 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
123 .width = 32, .phys = 32, .le = 0, .signd = -1,
124 .silence = {},
125 },
126 [SNDRV_PCM_FORMAT_MU_LAW] = {
127 .width = 8, .phys = 8, .le = -1, .signd = -1,
128 .silence = { 0x7f },
129 },
130 [SNDRV_PCM_FORMAT_A_LAW] = {
131 .width = 8, .phys = 8, .le = -1, .signd = -1,
132 .silence = { 0x55 },
133 },
134 [SNDRV_PCM_FORMAT_IMA_ADPCM] = {
135 .width = 4, .phys = 4, .le = -1, .signd = -1,
136 .silence = {},
137 },
138 [SNDRV_PCM_FORMAT_G723_24] = {
139 .width = 3, .phys = 3, .le = -1, .signd = -1,
140 .silence = {},
141 },
142 [SNDRV_PCM_FORMAT_G723_40] = {
143 .width = 5, .phys = 5, .le = -1, .signd = -1,
144 .silence = {},
145 },
146 [SNDRV_PCM_FORMAT_DSD_U8] = {
147 .width = 8, .phys = 8, .le = 1, .signd = 0,
148 .silence = { 0x69 },
149 },
150 [SNDRV_PCM_FORMAT_DSD_U16_LE] = {
151 .width = 16, .phys = 16, .le = 1, .signd = 0,
152 .silence = { 0x69, 0x69 },
153 },
154 [SNDRV_PCM_FORMAT_DSD_U32_LE] = {
155 .width = 32, .phys = 32, .le = 1, .signd = 0,
156 .silence = { 0x69, 0x69, 0x69, 0x69 },
157 },
158 [SNDRV_PCM_FORMAT_DSD_U16_BE] = {
159 .width = 16, .phys = 16, .le = 0, .signd = 0,
160 .silence = { 0x69, 0x69 },
161 },
162 [SNDRV_PCM_FORMAT_DSD_U32_BE] = {
163 .width = 32, .phys = 32, .le = 0, .signd = 0,
164 .silence = { 0x69, 0x69, 0x69, 0x69 },
165 },
166 /* FIXME: the following two formats are not defined properly yet */
167 [SNDRV_PCM_FORMAT_MPEG] = {
168 .le = -1, .signd = -1,
169 },
170 [SNDRV_PCM_FORMAT_GSM] = {
171 .le = -1, .signd = -1,
172 },
173 [SNDRV_PCM_FORMAT_S20_LE] = {
174 .width = 20, .phys = 32, .le = 1, .signd = 1,
175 .silence = {},
176 },
177 [SNDRV_PCM_FORMAT_S20_BE] = {
178 .width = 20, .phys = 32, .le = 0, .signd = 1,
179 .silence = {},
180 },
181 [SNDRV_PCM_FORMAT_U20_LE] = {
182 .width = 20, .phys = 32, .le = 1, .signd = 0,
183 .silence = { 0x00, 0x00, 0x08, 0x00 },
184 },
185 [SNDRV_PCM_FORMAT_U20_BE] = {
186 .width = 20, .phys = 32, .le = 0, .signd = 0,
187 .silence = { 0x00, 0x08, 0x00, 0x00 },
188 },
189 /* FIXME: the following format is not defined properly yet */
190 [SNDRV_PCM_FORMAT_SPECIAL] = {
191 .le = -1, .signd = -1,
192 },
193 [SNDRV_PCM_FORMAT_S24_3LE] = {
194 .width = 24, .phys = 24, .le = 1, .signd = 1,
195 .silence = {},
196 },
197 [SNDRV_PCM_FORMAT_S24_3BE] = {
198 .width = 24, .phys = 24, .le = 0, .signd = 1,
199 .silence = {},
200 },
201 [SNDRV_PCM_FORMAT_U24_3LE] = {
202 .width = 24, .phys = 24, .le = 1, .signd = 0,
203 .silence = { 0x00, 0x00, 0x80 },
204 },
205 [SNDRV_PCM_FORMAT_U24_3BE] = {
206 .width = 24, .phys = 24, .le = 0, .signd = 0,
207 .silence = { 0x80, 0x00, 0x00 },
208 },
209 [SNDRV_PCM_FORMAT_S20_3LE] = {
210 .width = 20, .phys = 24, .le = 1, .signd = 1,
211 .silence = {},
212 },
213 [SNDRV_PCM_FORMAT_S20_3BE] = {
214 .width = 20, .phys = 24, .le = 0, .signd = 1,
215 .silence = {},
216 },
217 [SNDRV_PCM_FORMAT_U20_3LE] = {
218 .width = 20, .phys = 24, .le = 1, .signd = 0,
219 .silence = { 0x00, 0x00, 0x08 },
220 },
221 [SNDRV_PCM_FORMAT_U20_3BE] = {
222 .width = 20, .phys = 24, .le = 0, .signd = 0,
223 .silence = { 0x08, 0x00, 0x00 },
224 },
225 [SNDRV_PCM_FORMAT_S18_3LE] = {
226 .width = 18, .phys = 24, .le = 1, .signd = 1,
227 .silence = {},
228 },
229 [SNDRV_PCM_FORMAT_S18_3BE] = {
230 .width = 18, .phys = 24, .le = 0, .signd = 1,
231 .silence = {},
232 },
233 [SNDRV_PCM_FORMAT_U18_3LE] = {
234 .width = 18, .phys = 24, .le = 1, .signd = 0,
235 .silence = { 0x00, 0x00, 0x02 },
236 },
237 [SNDRV_PCM_FORMAT_U18_3BE] = {
238 .width = 18, .phys = 24, .le = 0, .signd = 0,
239 .silence = { 0x02, 0x00, 0x00 },
240 },
241 [SNDRV_PCM_FORMAT_G723_24_1B] = {
242 .width = 3, .phys = 8, .le = -1, .signd = -1,
243 .silence = {},
244 },
245 [SNDRV_PCM_FORMAT_G723_40_1B] = {
246 .width = 5, .phys = 8, .le = -1, .signd = -1,
247 .silence = {},
248 },
249 };
250
251
252 /**
253 * snd_pcm_format_signed - Check the PCM format is signed linear
254 * @format: the format to check
255 *
256 * Return: 1 if the given PCM format is signed linear, 0 if unsigned
257 * linear, and a negative error code for non-linear formats.
258 */
snd_pcm_format_signed(snd_pcm_format_t format)259 int snd_pcm_format_signed(snd_pcm_format_t format)
260 {
261 int val;
262 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
263 return -EINVAL;
264 if ((val = pcm_formats[(INT)format].signd) < 0)
265 return -EINVAL;
266 return val;
267 }
268 EXPORT_SYMBOL(snd_pcm_format_signed);
269
270 /**
271 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
272 * @format: the format to check
273 *
274 * Return: 1 if the given PCM format is unsigned linear, 0 if signed
275 * linear, and a negative error code for non-linear formats.
276 */
snd_pcm_format_unsigned(snd_pcm_format_t format)277 int snd_pcm_format_unsigned(snd_pcm_format_t format)
278 {
279 int val;
280
281 val = snd_pcm_format_signed(format);
282 if (val < 0)
283 return val;
284 return !val;
285 }
286 EXPORT_SYMBOL(snd_pcm_format_unsigned);
287
288 /**
289 * snd_pcm_format_linear - Check the PCM format is linear
290 * @format: the format to check
291 *
292 * Return: 1 if the given PCM format is linear, 0 if not.
293 */
snd_pcm_format_linear(snd_pcm_format_t format)294 int snd_pcm_format_linear(snd_pcm_format_t format)
295 {
296 return snd_pcm_format_signed(format) >= 0;
297 }
298 EXPORT_SYMBOL(snd_pcm_format_linear);
299
300 /**
301 * snd_pcm_format_little_endian - Check the PCM format is little-endian
302 * @format: the format to check
303 *
304 * Return: 1 if the given PCM format is little-endian, 0 if
305 * big-endian, or a negative error code if endian not specified.
306 */
snd_pcm_format_little_endian(snd_pcm_format_t format)307 int snd_pcm_format_little_endian(snd_pcm_format_t format)
308 {
309 int val;
310 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
311 return -EINVAL;
312 if ((val = pcm_formats[(INT)format].le) < 0)
313 return -EINVAL;
314 return val;
315 }
316 EXPORT_SYMBOL(snd_pcm_format_little_endian);
317
318 /**
319 * snd_pcm_format_big_endian - Check the PCM format is big-endian
320 * @format: the format to check
321 *
322 * Return: 1 if the given PCM format is big-endian, 0 if
323 * little-endian, or a negative error code if endian not specified.
324 */
snd_pcm_format_big_endian(snd_pcm_format_t format)325 int snd_pcm_format_big_endian(snd_pcm_format_t format)
326 {
327 int val;
328
329 val = snd_pcm_format_little_endian(format);
330 if (val < 0)
331 return val;
332 return !val;
333 }
334 EXPORT_SYMBOL(snd_pcm_format_big_endian);
335
336 /**
337 * snd_pcm_format_width - return the bit-width of the format
338 * @format: the format to check
339 *
340 * Return: The bit-width of the format, or a negative error code
341 * if unknown format.
342 */
snd_pcm_format_width(snd_pcm_format_t format)343 int snd_pcm_format_width(snd_pcm_format_t format)
344 {
345 int val;
346 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
347 return -EINVAL;
348 if ((val = pcm_formats[(INT)format].width) == 0)
349 return -EINVAL;
350 return val;
351 }
352 EXPORT_SYMBOL(snd_pcm_format_width);
353
354 /**
355 * snd_pcm_format_physical_width - return the physical bit-width of the format
356 * @format: the format to check
357 *
358 * Return: The physical bit-width of the format, or a negative error code
359 * if unknown format.
360 */
snd_pcm_format_physical_width(snd_pcm_format_t format)361 int snd_pcm_format_physical_width(snd_pcm_format_t format)
362 {
363 int val;
364 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
365 return -EINVAL;
366 if ((val = pcm_formats[(INT)format].phys) == 0)
367 return -EINVAL;
368 return val;
369 }
370 EXPORT_SYMBOL(snd_pcm_format_physical_width);
371
372 /**
373 * snd_pcm_format_size - return the byte size of samples on the given format
374 * @format: the format to check
375 * @samples: sampling rate
376 *
377 * Return: The byte size of the given samples for the format, or a
378 * negative error code if unknown format.
379 */
snd_pcm_format_size(snd_pcm_format_t format,size_t samples)380 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
381 {
382 int phys_width = snd_pcm_format_physical_width(format);
383 if (phys_width < 0)
384 return -EINVAL;
385 return samples * phys_width / 8;
386 }
387 EXPORT_SYMBOL(snd_pcm_format_size);
388
389 /**
390 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
391 * @format: the format to check
392 *
393 * Return: The format pattern to fill or %NULL if error.
394 */
snd_pcm_format_silence_64(snd_pcm_format_t format)395 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
396 {
397 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
398 return NULL;
399 if (! pcm_formats[(INT)format].phys)
400 return NULL;
401 return pcm_formats[(INT)format].silence;
402 }
403 EXPORT_SYMBOL(snd_pcm_format_silence_64);
404
405 /**
406 * snd_pcm_format_set_silence - set the silence data on the buffer
407 * @format: the PCM format
408 * @data: the buffer pointer
409 * @samples: the number of samples to set silence
410 *
411 * Sets the silence data on the buffer for the given samples.
412 *
413 * Return: Zero if successful, or a negative error code on failure.
414 */
snd_pcm_format_set_silence(snd_pcm_format_t format,void * data,unsigned int samples)415 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
416 {
417 int width;
418 unsigned char *dst, *pat;
419
420 if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
421 return -EINVAL;
422 if (samples == 0)
423 return 0;
424 width = pcm_formats[(INT)format].phys; /* physical width */
425 pat = pcm_formats[(INT)format].silence;
426 if (! width)
427 return -EINVAL;
428 /* signed or 1 byte data */
429 if (pcm_formats[(INT)format].signd == 1 || width <= 8) {
430 unsigned int bytes = samples * width / 8;
431 memset(data, *pat, bytes);
432 return 0;
433 }
434 /* non-zero samples, fill using a loop */
435 width /= 8;
436 dst = data;
437 #if 0
438 while (samples--) {
439 memcpy(dst, pat, width);
440 dst += width;
441 }
442 #else
443 /* a bit optimization for constant width */
444 switch (width) {
445 case 2:
446 while (samples--) {
447 memcpy(dst, pat, 2);
448 dst += 2;
449 }
450 break;
451 case 3:
452 while (samples--) {
453 memcpy(dst, pat, 3);
454 dst += 3;
455 }
456 break;
457 case 4:
458 while (samples--) {
459 memcpy(dst, pat, 4);
460 dst += 4;
461 }
462 break;
463 case 8:
464 while (samples--) {
465 memcpy(dst, pat, 8);
466 dst += 8;
467 }
468 break;
469 }
470 #endif
471 return 0;
472 }
473 EXPORT_SYMBOL(snd_pcm_format_set_silence);
474
475 /**
476 * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
477 * @runtime: the runtime instance
478 *
479 * Determines the rate_min and rate_max fields from the rates bits of
480 * the given runtime->hw.
481 *
482 * Return: Zero if successful.
483 */
snd_pcm_limit_hw_rates(struct snd_pcm_runtime * runtime)484 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
485 {
486 int i;
487 for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
488 if (runtime->hw.rates & (1 << i)) {
489 runtime->hw.rate_min = snd_pcm_known_rates.list[i];
490 break;
491 }
492 }
493 for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
494 if (runtime->hw.rates & (1 << i)) {
495 runtime->hw.rate_max = snd_pcm_known_rates.list[i];
496 break;
497 }
498 }
499 return 0;
500 }
501 EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
502
503 /**
504 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
505 * @rate: the sample rate to convert
506 *
507 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
508 * SNDRV_PCM_RATE_KNOT for an unknown rate.
509 */
snd_pcm_rate_to_rate_bit(unsigned int rate)510 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
511 {
512 unsigned int i;
513
514 for (i = 0; i < snd_pcm_known_rates.count; i++)
515 if (snd_pcm_known_rates.list[i] == rate)
516 return 1u << i;
517 return SNDRV_PCM_RATE_KNOT;
518 }
519 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);
520
521 /**
522 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate
523 * @rate_bit: the rate bit to convert
524 *
525 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag
526 * or 0 for an unknown rate bit.
527 */
snd_pcm_rate_bit_to_rate(unsigned int rate_bit)528 unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit)
529 {
530 unsigned int i;
531
532 for (i = 0; i < snd_pcm_known_rates.count; i++)
533 if ((1u << i) == rate_bit)
534 return snd_pcm_known_rates.list[i];
535 return 0;
536 }
537 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate);
538
snd_pcm_rate_mask_sanitize(unsigned int rates)539 static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates)
540 {
541 if (rates & SNDRV_PCM_RATE_CONTINUOUS)
542 return SNDRV_PCM_RATE_CONTINUOUS;
543 else if (rates & SNDRV_PCM_RATE_KNOT)
544 return SNDRV_PCM_RATE_KNOT;
545 return rates;
546 }
547
548 /**
549 * snd_pcm_rate_mask_intersect - computes the intersection between two rate masks
550 * @rates_a: The first rate mask
551 * @rates_b: The second rate mask
552 *
553 * This function computes the rates that are supported by both rate masks passed
554 * to the function. It will take care of the special handling of
555 * SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT.
556 *
557 * Return: A rate mask containing the rates that are supported by both rates_a
558 * and rates_b.
559 */
snd_pcm_rate_mask_intersect(unsigned int rates_a,unsigned int rates_b)560 unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a,
561 unsigned int rates_b)
562 {
563 rates_a = snd_pcm_rate_mask_sanitize(rates_a);
564 rates_b = snd_pcm_rate_mask_sanitize(rates_b);
565
566 if (rates_a & SNDRV_PCM_RATE_CONTINUOUS)
567 return rates_b;
568 else if (rates_b & SNDRV_PCM_RATE_CONTINUOUS)
569 return rates_a;
570 else if (rates_a & SNDRV_PCM_RATE_KNOT)
571 return rates_b;
572 else if (rates_b & SNDRV_PCM_RATE_KNOT)
573 return rates_a;
574 return rates_a & rates_b;
575 }
576 EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect);
577
578 /**
579 * snd_pcm_rate_range_to_bits - converts rate range to SNDRV_PCM_RATE_xxx bit
580 * @rate_min: the minimum sample rate
581 * @rate_max: the maximum sample rate
582 *
583 * This function has an implicit assumption: the rates in the given range have
584 * only the pre-defined rates like 44100 or 16000.
585 *
586 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate range,
587 * or SNDRV_PCM_RATE_KNOT for an unknown range.
588 */
snd_pcm_rate_range_to_bits(unsigned int rate_min,unsigned int rate_max)589 unsigned int snd_pcm_rate_range_to_bits(unsigned int rate_min,
590 unsigned int rate_max)
591 {
592 unsigned int rates = 0;
593 int i;
594
595 for (i = 0; i < snd_pcm_known_rates.count; i++) {
596 if (snd_pcm_known_rates.list[i] >= rate_min
597 && snd_pcm_known_rates.list[i] <= rate_max)
598 rates |= 1 << i;
599 }
600
601 if (!rates)
602 rates = SNDRV_PCM_RATE_KNOT;
603
604 return rates;
605 }
606 EXPORT_SYMBOL_GPL(snd_pcm_rate_range_to_bits);
607
