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>
26 #define SND_PCM_FORMAT_UNKNOWN (-1)
28 /* NOTE: "signed" prefix must be given below since the default char is
29 * unsigned on some architectures!
31 struct pcm_format_data
{
32 unsigned char width
; /* bit width */
33 unsigned char phys
; /* physical bit width */
34 signed char le
; /* 0 = big-endian, 1 = little-endian, -1 = others */
35 signed char signd
; /* 0 = unsigned, 1 = signed, -1 = others */
36 unsigned char silence
[8]; /* silence data to fill */
39 /* we do lots of calculations on snd_pcm_format_t; shut up sparse */
40 #define INT __force int
42 static struct pcm_format_data pcm_formats
[(INT
)SNDRV_PCM_FORMAT_LAST
+1] = {
43 [SNDRV_PCM_FORMAT_S8
] = {
44 .width
= 8, .phys
= 8, .le
= -1, .signd
= 1,
47 [SNDRV_PCM_FORMAT_U8
] = {
48 .width
= 8, .phys
= 8, .le
= -1, .signd
= 0,
51 [SNDRV_PCM_FORMAT_S16_LE
] = {
52 .width
= 16, .phys
= 16, .le
= 1, .signd
= 1,
55 [SNDRV_PCM_FORMAT_S16_BE
] = {
56 .width
= 16, .phys
= 16, .le
= 0, .signd
= 1,
59 [SNDRV_PCM_FORMAT_U16_LE
] = {
60 .width
= 16, .phys
= 16, .le
= 1, .signd
= 0,
61 .silence
= { 0x00, 0x80 },
63 [SNDRV_PCM_FORMAT_U16_BE
] = {
64 .width
= 16, .phys
= 16, .le
= 0, .signd
= 0,
65 .silence
= { 0x80, 0x00 },
67 [SNDRV_PCM_FORMAT_S24_LE
] = {
68 .width
= 24, .phys
= 32, .le
= 1, .signd
= 1,
71 [SNDRV_PCM_FORMAT_S24_BE
] = {
72 .width
= 24, .phys
= 32, .le
= 0, .signd
= 1,
75 [SNDRV_PCM_FORMAT_U24_LE
] = {
76 .width
= 24, .phys
= 32, .le
= 1, .signd
= 0,
77 .silence
= { 0x00, 0x00, 0x80 },
79 [SNDRV_PCM_FORMAT_U24_BE
] = {
80 .width
= 24, .phys
= 32, .le
= 0, .signd
= 0,
81 .silence
= { 0x00, 0x80, 0x00, 0x00 },
83 [SNDRV_PCM_FORMAT_S32_LE
] = {
84 .width
= 32, .phys
= 32, .le
= 1, .signd
= 1,
87 [SNDRV_PCM_FORMAT_S32_BE
] = {
88 .width
= 32, .phys
= 32, .le
= 0, .signd
= 1,
91 [SNDRV_PCM_FORMAT_U32_LE
] = {
92 .width
= 32, .phys
= 32, .le
= 1, .signd
= 0,
93 .silence
= { 0x00, 0x00, 0x00, 0x80 },
95 [SNDRV_PCM_FORMAT_U32_BE
] = {
96 .width
= 32, .phys
= 32, .le
= 0, .signd
= 0,
97 .silence
= { 0x80, 0x00, 0x00, 0x00 },
99 [SNDRV_PCM_FORMAT_FLOAT_LE
] = {
100 .width
= 32, .phys
= 32, .le
= 1, .signd
= -1,
103 [SNDRV_PCM_FORMAT_FLOAT_BE
] = {
104 .width
= 32, .phys
= 32, .le
= 0, .signd
= -1,
107 [SNDRV_PCM_FORMAT_FLOAT64_LE
] = {
108 .width
= 64, .phys
= 64, .le
= 1, .signd
= -1,
111 [SNDRV_PCM_FORMAT_FLOAT64_BE
] = {
112 .width
= 64, .phys
= 64, .le
= 0, .signd
= -1,
115 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE
] = {
116 .width
= 32, .phys
= 32, .le
= 1, .signd
= -1,
119 [SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE
] = {
120 .width
= 32, .phys
= 32, .le
= 0, .signd
= -1,
123 [SNDRV_PCM_FORMAT_MU_LAW
] = {
124 .width
= 8, .phys
= 8, .le
= -1, .signd
= -1,
127 [SNDRV_PCM_FORMAT_A_LAW
] = {
128 .width
= 8, .phys
= 8, .le
= -1, .signd
= -1,
131 [SNDRV_PCM_FORMAT_IMA_ADPCM
] = {
132 .width
= 4, .phys
= 4, .le
= -1, .signd
= -1,
135 [SNDRV_PCM_FORMAT_G723_24
] = {
136 .width
= 3, .phys
= 3, .le
= -1, .signd
= -1,
139 [SNDRV_PCM_FORMAT_G723_40
] = {
140 .width
= 5, .phys
= 5, .le
= -1, .signd
= -1,
143 [SNDRV_PCM_FORMAT_DSD_U8
] = {
144 .width
= 8, .phys
= 8, .le
= 1, .signd
= 0,
147 [SNDRV_PCM_FORMAT_DSD_U16_LE
] = {
148 .width
= 16, .phys
= 16, .le
= 1, .signd
= 0,
149 .silence
= { 0x69, 0x69 },
151 [SNDRV_PCM_FORMAT_DSD_U32_LE
] = {
152 .width
= 32, .phys
= 32, .le
= 1, .signd
= 0,
153 .silence
= { 0x69, 0x69, 0x69, 0x69 },
155 [SNDRV_PCM_FORMAT_DSD_U16_BE
] = {
156 .width
= 16, .phys
= 16, .le
= 0, .signd
= 0,
157 .silence
= { 0x69, 0x69 },
159 [SNDRV_PCM_FORMAT_DSD_U32_BE
] = {
160 .width
= 32, .phys
= 32, .le
= 0, .signd
= 0,
161 .silence
= { 0x69, 0x69, 0x69, 0x69 },
163 /* FIXME: the following three formats are not defined properly yet */
164 [SNDRV_PCM_FORMAT_MPEG
] = {
165 .le
= -1, .signd
= -1,
167 [SNDRV_PCM_FORMAT_GSM
] = {
168 .le
= -1, .signd
= -1,
170 [SNDRV_PCM_FORMAT_SPECIAL
] = {
171 .le
= -1, .signd
= -1,
173 [SNDRV_PCM_FORMAT_S24_3LE
] = {
174 .width
= 24, .phys
= 24, .le
= 1, .signd
= 1,
177 [SNDRV_PCM_FORMAT_S24_3BE
] = {
178 .width
= 24, .phys
= 24, .le
= 0, .signd
= 1,
181 [SNDRV_PCM_FORMAT_U24_3LE
] = {
182 .width
= 24, .phys
= 24, .le
= 1, .signd
= 0,
183 .silence
= { 0x00, 0x00, 0x80 },
185 [SNDRV_PCM_FORMAT_U24_3BE
] = {
186 .width
= 24, .phys
= 24, .le
= 0, .signd
= 0,
187 .silence
= { 0x80, 0x00, 0x00 },
189 [SNDRV_PCM_FORMAT_S20_3LE
] = {
190 .width
= 20, .phys
= 24, .le
= 1, .signd
= 1,
193 [SNDRV_PCM_FORMAT_S20_3BE
] = {
194 .width
= 20, .phys
= 24, .le
= 0, .signd
= 1,
197 [SNDRV_PCM_FORMAT_U20_3LE
] = {
198 .width
= 20, .phys
= 24, .le
= 1, .signd
= 0,
199 .silence
= { 0x00, 0x00, 0x08 },
201 [SNDRV_PCM_FORMAT_U20_3BE
] = {
202 .width
= 20, .phys
= 24, .le
= 0, .signd
= 0,
203 .silence
= { 0x08, 0x00, 0x00 },
205 [SNDRV_PCM_FORMAT_S18_3LE
] = {
206 .width
= 18, .phys
= 24, .le
= 1, .signd
= 1,
209 [SNDRV_PCM_FORMAT_S18_3BE
] = {
210 .width
= 18, .phys
= 24, .le
= 0, .signd
= 1,
213 [SNDRV_PCM_FORMAT_U18_3LE
] = {
214 .width
= 18, .phys
= 24, .le
= 1, .signd
= 0,
215 .silence
= { 0x00, 0x00, 0x02 },
217 [SNDRV_PCM_FORMAT_U18_3BE
] = {
218 .width
= 18, .phys
= 24, .le
= 0, .signd
= 0,
219 .silence
= { 0x02, 0x00, 0x00 },
221 [SNDRV_PCM_FORMAT_G723_24_1B
] = {
222 .width
= 3, .phys
= 8, .le
= -1, .signd
= -1,
225 [SNDRV_PCM_FORMAT_G723_40_1B
] = {
226 .width
= 5, .phys
= 8, .le
= -1, .signd
= -1,
233 * snd_pcm_format_signed - Check the PCM format is signed linear
234 * @format: the format to check
236 * Return: 1 if the given PCM format is signed linear, 0 if unsigned
237 * linear, and a negative error code for non-linear formats.
239 int snd_pcm_format_signed(snd_pcm_format_t format
)
242 if ((INT
)format
< 0 || (INT
)format
> (INT
)SNDRV_PCM_FORMAT_LAST
)
244 if ((val
= pcm_formats
[(INT
)format
].signd
) < 0)
249 EXPORT_SYMBOL(snd_pcm_format_signed
);
252 * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
253 * @format: the format to check
255 * Return: 1 if the given PCM format is unsigned linear, 0 if signed
256 * linear, and a negative error code for non-linear formats.
258 int snd_pcm_format_unsigned(snd_pcm_format_t format
)
262 val
= snd_pcm_format_signed(format
);
268 EXPORT_SYMBOL(snd_pcm_format_unsigned
);
271 * snd_pcm_format_linear - Check the PCM format is linear
272 * @format: the format to check
274 * Return: 1 if the given PCM format is linear, 0 if not.
276 int snd_pcm_format_linear(snd_pcm_format_t format
)
278 return snd_pcm_format_signed(format
) >= 0;
281 EXPORT_SYMBOL(snd_pcm_format_linear
);
284 * snd_pcm_format_little_endian - Check the PCM format is little-endian
285 * @format: the format to check
287 * Return: 1 if the given PCM format is little-endian, 0 if
288 * big-endian, or a negative error code if endian not specified.
290 int snd_pcm_format_little_endian(snd_pcm_format_t format
)
293 if ((INT
)format
< 0 || (INT
)format
> (INT
)SNDRV_PCM_FORMAT_LAST
)
295 if ((val
= pcm_formats
[(INT
)format
].le
) < 0)
300 EXPORT_SYMBOL(snd_pcm_format_little_endian
);
303 * snd_pcm_format_big_endian - Check the PCM format is big-endian
304 * @format: the format to check
306 * Return: 1 if the given PCM format is big-endian, 0 if
307 * little-endian, or a negative error code if endian not specified.
309 int snd_pcm_format_big_endian(snd_pcm_format_t format
)
313 val
= snd_pcm_format_little_endian(format
);
319 EXPORT_SYMBOL(snd_pcm_format_big_endian
);
322 * snd_pcm_format_width - return the bit-width of the format
323 * @format: the format to check
325 * Return: The bit-width of the format, or a negative error code
328 int snd_pcm_format_width(snd_pcm_format_t format
)
331 if ((INT
)format
< 0 || (INT
)format
> (INT
)SNDRV_PCM_FORMAT_LAST
)
333 if ((val
= pcm_formats
[(INT
)format
].width
) == 0)
338 EXPORT_SYMBOL(snd_pcm_format_width
);
341 * snd_pcm_format_physical_width - return the physical bit-width of the format
342 * @format: the format to check
344 * Return: The physical bit-width of the format, or a negative error code
347 int snd_pcm_format_physical_width(snd_pcm_format_t format
)
350 if ((INT
)format
< 0 || (INT
)format
> (INT
)SNDRV_PCM_FORMAT_LAST
)
352 if ((val
= pcm_formats
[(INT
)format
].phys
) == 0)
357 EXPORT_SYMBOL(snd_pcm_format_physical_width
);
360 * snd_pcm_format_size - return the byte size of samples on the given format
361 * @format: the format to check
362 * @samples: sampling rate
364 * Return: The byte size of the given samples for the format, or a
365 * negative error code if unknown format.
367 ssize_t
snd_pcm_format_size(snd_pcm_format_t format
, size_t samples
)
369 int phys_width
= snd_pcm_format_physical_width(format
);
372 return samples
* phys_width
/ 8;
375 EXPORT_SYMBOL(snd_pcm_format_size
);
378 * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
379 * @format: the format to check
381 * Return: The format pattern to fill or %NULL if error.
383 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format
)
385 if ((INT
)format
< 0 || (INT
)format
> (INT
)SNDRV_PCM_FORMAT_LAST
)
387 if (! pcm_formats
[(INT
)format
].phys
)
389 return pcm_formats
[(INT
)format
].silence
;
392 EXPORT_SYMBOL(snd_pcm_format_silence_64
);
395 * snd_pcm_format_set_silence - set the silence data on the buffer
396 * @format: the PCM format
397 * @data: the buffer pointer
398 * @samples: the number of samples to set silence
400 * Sets the silence data on the buffer for the given samples.
402 * Return: Zero if successful, or a negative error code on failure.
404 int snd_pcm_format_set_silence(snd_pcm_format_t format
, void *data
, unsigned int samples
)
407 unsigned char *dst
, *pat
;
409 if ((INT
)format
< 0 || (INT
)format
> (INT
)SNDRV_PCM_FORMAT_LAST
)
413 width
= pcm_formats
[(INT
)format
].phys
; /* physical width */
414 pat
= pcm_formats
[(INT
)format
].silence
;
417 /* signed or 1 byte data */
418 if (pcm_formats
[(INT
)format
].signd
== 1 || width
<= 8) {
419 unsigned int bytes
= samples
* width
/ 8;
420 memset(data
, *pat
, bytes
);
423 /* non-zero samples, fill using a loop */
428 memcpy(dst
, pat
, width
);
432 /* a bit optimization for constant width */
463 EXPORT_SYMBOL(snd_pcm_format_set_silence
);
466 * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
467 * @runtime: the runtime instance
469 * Determines the rate_min and rate_max fields from the rates bits of
470 * the given runtime->hw.
472 * Return: Zero if successful.
474 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime
*runtime
)
477 for (i
= 0; i
< (int)snd_pcm_known_rates
.count
; i
++) {
478 if (runtime
->hw
.rates
& (1 << i
)) {
479 runtime
->hw
.rate_min
= snd_pcm_known_rates
.list
[i
];
483 for (i
= (int)snd_pcm_known_rates
.count
- 1; i
>= 0; i
--) {
484 if (runtime
->hw
.rates
& (1 << i
)) {
485 runtime
->hw
.rate_max
= snd_pcm_known_rates
.list
[i
];
492 EXPORT_SYMBOL(snd_pcm_limit_hw_rates
);
495 * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
496 * @rate: the sample rate to convert
498 * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
499 * SNDRV_PCM_RATE_KNOT for an unknown rate.
501 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate
)
505 for (i
= 0; i
< snd_pcm_known_rates
.count
; i
++)
506 if (snd_pcm_known_rates
.list
[i
] == rate
)
508 return SNDRV_PCM_RATE_KNOT
;
510 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit
);
513 * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate
514 * @rate_bit: the rate bit to convert
516 * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag
517 * or 0 for an unknown rate bit.
519 unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit
)
523 for (i
= 0; i
< snd_pcm_known_rates
.count
; i
++)
524 if ((1u << i
) == rate_bit
)
525 return snd_pcm_known_rates
.list
[i
];
528 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate
);
530 static unsigned int snd_pcm_rate_mask_sanitize(unsigned int rates
)
532 if (rates
& SNDRV_PCM_RATE_CONTINUOUS
)
533 return SNDRV_PCM_RATE_CONTINUOUS
;
534 else if (rates
& SNDRV_PCM_RATE_KNOT
)
535 return SNDRV_PCM_RATE_KNOT
;
540 * snd_pcm_rate_mask_intersect - computes the intersection between two rate masks
541 * @rates_a: The first rate mask
542 * @rates_b: The second rate mask
544 * This function computes the rates that are supported by both rate masks passed
545 * to the function. It will take care of the special handling of
546 * SNDRV_PCM_RATE_CONTINUOUS and SNDRV_PCM_RATE_KNOT.
548 * Return: A rate mask containing the rates that are supported by both rates_a
551 unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a
,
552 unsigned int rates_b
)
554 rates_a
= snd_pcm_rate_mask_sanitize(rates_a
);
555 rates_b
= snd_pcm_rate_mask_sanitize(rates_b
);
557 if (rates_a
& SNDRV_PCM_RATE_CONTINUOUS
)
559 else if (rates_b
& SNDRV_PCM_RATE_CONTINUOUS
)
561 else if (rates_a
& SNDRV_PCM_RATE_KNOT
)
563 else if (rates_b
& SNDRV_PCM_RATE_KNOT
)
565 return rates_a
& rates_b
;
567 EXPORT_SYMBOL_GPL(snd_pcm_rate_mask_intersect
);