xref: /openbmc/linux/sound/core/pcm_misc.c (revision e23feb16) 
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 #define SND_PCM_FORMAT_UNKNOWN (-1)
27 
28 /* NOTE: "signed" prefix must be given below since the default char is
29  *       unsigned on some architectures!
30  */
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 */
37 };
38 
39 /* we do lots of calculations on snd_pcm_format_t; shut up sparse */
40 #define INT	__force int
41 
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,
45 		.silence = {},
46 	},
47 	[SNDRV_PCM_FORMAT_U8] = {
48 		.width = 8, .phys = 8, .le = -1, .signd = 0,
49 		.silence = { 0x80 },
50 	},
51 	[SNDRV_PCM_FORMAT_S16_LE] = {
52 		.width = 16, .phys = 16, .le = 1, .signd = 1,
53 		.silence = {},
54 	},
55 	[SNDRV_PCM_FORMAT_S16_BE] = {
56 		.width = 16, .phys = 16, .le = 0, .signd = 1,
57 		.silence = {},
58 	},
59 	[SNDRV_PCM_FORMAT_U16_LE] = {
60 		.width = 16, .phys = 16, .le = 1, .signd = 0,
61 		.silence = { 0x00, 0x80 },
62 	},
63 	[SNDRV_PCM_FORMAT_U16_BE] = {
64 		.width = 16, .phys = 16, .le = 0, .signd = 0,
65 		.silence = { 0x80, 0x00 },
66 	},
67 	[SNDRV_PCM_FORMAT_S24_LE] = {
68 		.width = 24, .phys = 32, .le = 1, .signd = 1,
69 		.silence = {},
70 	},
71 	[SNDRV_PCM_FORMAT_S24_BE] = {
72 		.width = 24, .phys = 32, .le = 0, .signd = 1,
73 		.silence = {},
74 	},
75 	[SNDRV_PCM_FORMAT_U24_LE] = {
76 		.width = 24, .phys = 32, .le = 1, .signd = 0,
77 		.silence = { 0x00, 0x00, 0x80 },
78 	},
79 	[SNDRV_PCM_FORMAT_U24_BE] = {
80 		.width = 24, .phys = 32, .le = 0, .signd = 0,
81 		.silence = { 0x00, 0x80, 0x00, 0x00 },
82 	},
83 	[SNDRV_PCM_FORMAT_S32_LE] = {
84 		.width = 32, .phys = 32, .le = 1, .signd = 1,
85 		.silence = {},
86 	},
87 	[SNDRV_PCM_FORMAT_S32_BE] = {
88 		.width = 32, .phys = 32, .le = 0, .signd = 1,
89 		.silence = {},
90 	},
91 	[SNDRV_PCM_FORMAT_U32_LE] = {
92 		.width = 32, .phys = 32, .le = 1, .signd = 0,
93 		.silence = { 0x00, 0x00, 0x00, 0x80 },
94 	},
95 	[SNDRV_PCM_FORMAT_U32_BE] = {
96 		.width = 32, .phys = 32, .le = 0, .signd = 0,
97 		.silence = { 0x80, 0x00, 0x00, 0x00 },
98 	},
99 	[SNDRV_PCM_FORMAT_FLOAT_LE] = {
100 		.width = 32, .phys = 32, .le = 1, .signd = -1,
101 		.silence = {},
102 	},
103 	[SNDRV_PCM_FORMAT_FLOAT_BE] = {
104 		.width = 32, .phys = 32, .le = 0, .signd = -1,
105 		.silence = {},
106 	},
107 	[SNDRV_PCM_FORMAT_FLOAT64_LE] = {
108 		.width = 64, .phys = 64, .le = 1, .signd = -1,
109 		.silence = {},
110 	},
111 	[SNDRV_PCM_FORMAT_FLOAT64_BE] = {
112 		.width = 64, .phys = 64, .le = 0, .signd = -1,
113 		.silence = {},
114 	},
115 	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE] = {
116 		.width = 32, .phys = 32, .le = 1, .signd = -1,
117 		.silence = {},
118 	},
119 	[SNDRV_PCM_FORMAT_IEC958_SUBFRAME_BE] = {
120 		.width = 32, .phys = 32, .le = 0, .signd = -1,
121 		.silence = {},
122 	},
123 	[SNDRV_PCM_FORMAT_MU_LAW] = {
124 		.width = 8, .phys = 8, .le = -1, .signd = -1,
125 		.silence = { 0x7f },
126 	},
127 	[SNDRV_PCM_FORMAT_A_LAW] = {
128 		.width = 8, .phys = 8, .le = -1, .signd = -1,
129 		.silence = { 0x55 },
130 	},
131 	[SNDRV_PCM_FORMAT_IMA_ADPCM] = {
132 		.width = 4, .phys = 4, .le = -1, .signd = -1,
133 		.silence = {},
134 	},
135 	[SNDRV_PCM_FORMAT_G723_24] = {
136 		.width = 3, .phys = 3, .le = -1, .signd = -1,
137 		.silence = {},
138 	},
139 	[SNDRV_PCM_FORMAT_G723_40] = {
140 		.width = 5, .phys = 5, .le = -1, .signd = -1,
141 		.silence = {},
142 	},
143 	[SNDRV_PCM_FORMAT_DSD_U8] = {
144 		.width = 8, .phys = 8, .le = 1, .signd = 0,
145 		.silence = {},
146 	},
147 	[SNDRV_PCM_FORMAT_DSD_U16_LE] = {
148 		.width = 16, .phys = 16, .le = 1, .signd = 0,
149 		.silence = {},
150 	},
151 	/* FIXME: the following three formats are not defined properly yet */
152 	[SNDRV_PCM_FORMAT_MPEG] = {
153 		.le = -1, .signd = -1,
154 	},
155 	[SNDRV_PCM_FORMAT_GSM] = {
156 		.le = -1, .signd = -1,
157 	},
158 	[SNDRV_PCM_FORMAT_SPECIAL] = {
159 		.le = -1, .signd = -1,
160 	},
161 	[SNDRV_PCM_FORMAT_S24_3LE] = {
162 		.width = 24, .phys = 24, .le = 1, .signd = 1,
163 		.silence = {},
164 	},
165 	[SNDRV_PCM_FORMAT_S24_3BE] = {
166 		.width = 24, .phys = 24, .le = 0, .signd = 1,
167 		.silence = {},
168 	},
169 	[SNDRV_PCM_FORMAT_U24_3LE] = {
170 		.width = 24, .phys = 24, .le = 1, .signd = 0,
171 		.silence = { 0x00, 0x00, 0x80 },
172 	},
173 	[SNDRV_PCM_FORMAT_U24_3BE] = {
174 		.width = 24, .phys = 24, .le = 0, .signd = 0,
175 		.silence = { 0x80, 0x00, 0x00 },
176 	},
177 	[SNDRV_PCM_FORMAT_S20_3LE] = {
178 		.width = 20, .phys = 24, .le = 1, .signd = 1,
179 		.silence = {},
180 	},
181 	[SNDRV_PCM_FORMAT_S20_3BE] = {
182 		.width = 20, .phys = 24, .le = 0, .signd = 1,
183 		.silence = {},
184 	},
185 	[SNDRV_PCM_FORMAT_U20_3LE] = {
186 		.width = 20, .phys = 24, .le = 1, .signd = 0,
187 		.silence = { 0x00, 0x00, 0x08 },
188 	},
189 	[SNDRV_PCM_FORMAT_U20_3BE] = {
190 		.width = 20, .phys = 24, .le = 0, .signd = 0,
191 		.silence = { 0x08, 0x00, 0x00 },
192 	},
193 	[SNDRV_PCM_FORMAT_S18_3LE] = {
194 		.width = 18, .phys = 24, .le = 1, .signd = 1,
195 		.silence = {},
196 	},
197 	[SNDRV_PCM_FORMAT_S18_3BE] = {
198 		.width = 18, .phys = 24, .le = 0, .signd = 1,
199 		.silence = {},
200 	},
201 	[SNDRV_PCM_FORMAT_U18_3LE] = {
202 		.width = 18, .phys = 24, .le = 1, .signd = 0,
203 		.silence = { 0x00, 0x00, 0x02 },
204 	},
205 	[SNDRV_PCM_FORMAT_U18_3BE] = {
206 		.width = 18, .phys = 24, .le = 0, .signd = 0,
207 		.silence = { 0x02, 0x00, 0x00 },
208 	},
209 	[SNDRV_PCM_FORMAT_G723_24_1B] = {
210 		.width = 3, .phys = 8, .le = -1, .signd = -1,
211 		.silence = {},
212 	},
213 	[SNDRV_PCM_FORMAT_G723_40_1B] = {
214 		.width = 5, .phys = 8, .le = -1, .signd = -1,
215 		.silence = {},
216 	},
217 };
218 
219 
220 /**
221  * snd_pcm_format_signed - Check the PCM format is signed linear
222  * @format: the format to check
223  *
224  * Return: 1 if the given PCM format is signed linear, 0 if unsigned
225  * linear, and a negative error code for non-linear formats.
226  */
227 int snd_pcm_format_signed(snd_pcm_format_t format)
228 {
229 	int val;
230 	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
231 		return -EINVAL;
232 	if ((val = pcm_formats[(INT)format].signd) < 0)
233 		return -EINVAL;
234 	return val;
235 }
236 
237 EXPORT_SYMBOL(snd_pcm_format_signed);
238 
239 /**
240  * snd_pcm_format_unsigned - Check the PCM format is unsigned linear
241  * @format: the format to check
242  *
243  * Return: 1 if the given PCM format is unsigned linear, 0 if signed
244  * linear, and a negative error code for non-linear formats.
245  */
246 int snd_pcm_format_unsigned(snd_pcm_format_t format)
247 {
248 	int val;
249 
250 	val = snd_pcm_format_signed(format);
251 	if (val < 0)
252 		return val;
253 	return !val;
254 }
255 
256 EXPORT_SYMBOL(snd_pcm_format_unsigned);
257 
258 /**
259  * snd_pcm_format_linear - Check the PCM format is linear
260  * @format: the format to check
261  *
262  * Return: 1 if the given PCM format is linear, 0 if not.
263  */
264 int snd_pcm_format_linear(snd_pcm_format_t format)
265 {
266 	return snd_pcm_format_signed(format) >= 0;
267 }
268 
269 EXPORT_SYMBOL(snd_pcm_format_linear);
270 
271 /**
272  * snd_pcm_format_little_endian - Check the PCM format is little-endian
273  * @format: the format to check
274  *
275  * Return: 1 if the given PCM format is little-endian, 0 if
276  * big-endian, or a negative error code if endian not specified.
277  */
278 int snd_pcm_format_little_endian(snd_pcm_format_t format)
279 {
280 	int val;
281 	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
282 		return -EINVAL;
283 	if ((val = pcm_formats[(INT)format].le) < 0)
284 		return -EINVAL;
285 	return val;
286 }
287 
288 EXPORT_SYMBOL(snd_pcm_format_little_endian);
289 
290 /**
291  * snd_pcm_format_big_endian - Check the PCM format is big-endian
292  * @format: the format to check
293  *
294  * Return: 1 if the given PCM format is big-endian, 0 if
295  * little-endian, or a negative error code if endian not specified.
296  */
297 int snd_pcm_format_big_endian(snd_pcm_format_t format)
298 {
299 	int val;
300 
301 	val = snd_pcm_format_little_endian(format);
302 	if (val < 0)
303 		return val;
304 	return !val;
305 }
306 
307 EXPORT_SYMBOL(snd_pcm_format_big_endian);
308 
309 /**
310  * snd_pcm_format_width - return the bit-width of the format
311  * @format: the format to check
312  *
313  * Return: The bit-width of the format, or a negative error code
314  * if unknown format.
315  */
316 int snd_pcm_format_width(snd_pcm_format_t format)
317 {
318 	int val;
319 	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
320 		return -EINVAL;
321 	if ((val = pcm_formats[(INT)format].width) == 0)
322 		return -EINVAL;
323 	return val;
324 }
325 
326 EXPORT_SYMBOL(snd_pcm_format_width);
327 
328 /**
329  * snd_pcm_format_physical_width - return the physical bit-width of the format
330  * @format: the format to check
331  *
332  * Return: The physical bit-width of the format, or a negative error code
333  * if unknown format.
334  */
335 int snd_pcm_format_physical_width(snd_pcm_format_t format)
336 {
337 	int val;
338 	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
339 		return -EINVAL;
340 	if ((val = pcm_formats[(INT)format].phys) == 0)
341 		return -EINVAL;
342 	return val;
343 }
344 
345 EXPORT_SYMBOL(snd_pcm_format_physical_width);
346 
347 /**
348  * snd_pcm_format_size - return the byte size of samples on the given format
349  * @format: the format to check
350  * @samples: sampling rate
351  *
352  * Return: The byte size of the given samples for the format, or a
353  * negative error code if unknown format.
354  */
355 ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples)
356 {
357 	int phys_width = snd_pcm_format_physical_width(format);
358 	if (phys_width < 0)
359 		return -EINVAL;
360 	return samples * phys_width / 8;
361 }
362 
363 EXPORT_SYMBOL(snd_pcm_format_size);
364 
365 /**
366  * snd_pcm_format_silence_64 - return the silent data in 8 bytes array
367  * @format: the format to check
368  *
369  * Return: The format pattern to fill or %NULL if error.
370  */
371 const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format)
372 {
373 	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
374 		return NULL;
375 	if (! pcm_formats[(INT)format].phys)
376 		return NULL;
377 	return pcm_formats[(INT)format].silence;
378 }
379 
380 EXPORT_SYMBOL(snd_pcm_format_silence_64);
381 
382 /**
383  * snd_pcm_format_set_silence - set the silence data on the buffer
384  * @format: the PCM format
385  * @data: the buffer pointer
386  * @samples: the number of samples to set silence
387  *
388  * Sets the silence data on the buffer for the given samples.
389  *
390  * Return: Zero if successful, or a negative error code on failure.
391  */
392 int snd_pcm_format_set_silence(snd_pcm_format_t format, void *data, unsigned int samples)
393 {
394 	int width;
395 	unsigned char *dst, *pat;
396 
397 	if ((INT)format < 0 || (INT)format > (INT)SNDRV_PCM_FORMAT_LAST)
398 		return -EINVAL;
399 	if (samples == 0)
400 		return 0;
401 	width = pcm_formats[(INT)format].phys; /* physical width */
402 	pat = pcm_formats[(INT)format].silence;
403 	if (! width)
404 		return -EINVAL;
405 	/* signed or 1 byte data */
406 	if (pcm_formats[(INT)format].signd == 1 || width <= 8) {
407 		unsigned int bytes = samples * width / 8;
408 		memset(data, *pat, bytes);
409 		return 0;
410 	}
411 	/* non-zero samples, fill using a loop */
412 	width /= 8;
413 	dst = data;
414 #if 0
415 	while (samples--) {
416 		memcpy(dst, pat, width);
417 		dst += width;
418 	}
419 #else
420 	/* a bit optimization for constant width */
421 	switch (width) {
422 	case 2:
423 		while (samples--) {
424 			memcpy(dst, pat, 2);
425 			dst += 2;
426 		}
427 		break;
428 	case 3:
429 		while (samples--) {
430 			memcpy(dst, pat, 3);
431 			dst += 3;
432 		}
433 		break;
434 	case 4:
435 		while (samples--) {
436 			memcpy(dst, pat, 4);
437 			dst += 4;
438 		}
439 		break;
440 	case 8:
441 		while (samples--) {
442 			memcpy(dst, pat, 8);
443 			dst += 8;
444 		}
445 		break;
446 	}
447 #endif
448 	return 0;
449 }
450 
451 EXPORT_SYMBOL(snd_pcm_format_set_silence);
452 
453 /**
454  * snd_pcm_limit_hw_rates - determine rate_min/rate_max fields
455  * @runtime: the runtime instance
456  *
457  * Determines the rate_min and rate_max fields from the rates bits of
458  * the given runtime->hw.
459  *
460  * Return: Zero if successful.
461  */
462 int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
463 {
464 	int i;
465 	for (i = 0; i < (int)snd_pcm_known_rates.count; i++) {
466 		if (runtime->hw.rates & (1 << i)) {
467 			runtime->hw.rate_min = snd_pcm_known_rates.list[i];
468 			break;
469 		}
470 	}
471 	for (i = (int)snd_pcm_known_rates.count - 1; i >= 0; i--) {
472 		if (runtime->hw.rates & (1 << i)) {
473 			runtime->hw.rate_max = snd_pcm_known_rates.list[i];
474 			break;
475 		}
476 	}
477 	return 0;
478 }
479 
480 EXPORT_SYMBOL(snd_pcm_limit_hw_rates);
481 
482 /**
483  * snd_pcm_rate_to_rate_bit - converts sample rate to SNDRV_PCM_RATE_xxx bit
484  * @rate: the sample rate to convert
485  *
486  * Return: The SNDRV_PCM_RATE_xxx flag that corresponds to the given rate, or
487  * SNDRV_PCM_RATE_KNOT for an unknown rate.
488  */
489 unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate)
490 {
491 	unsigned int i;
492 
493 	for (i = 0; i < snd_pcm_known_rates.count; i++)
494 		if (snd_pcm_known_rates.list[i] == rate)
495 			return 1u << i;
496 	return SNDRV_PCM_RATE_KNOT;
497 }
498 EXPORT_SYMBOL(snd_pcm_rate_to_rate_bit);
499 
500 /**
501  * snd_pcm_rate_bit_to_rate - converts SNDRV_PCM_RATE_xxx bit to sample rate
502  * @rate_bit: the rate bit to convert
503  *
504  * Return: The sample rate that corresponds to the given SNDRV_PCM_RATE_xxx flag
505  * or 0 for an unknown rate bit.
506  */
507 unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit)
508 {
509 	unsigned int i;
510 
511 	for (i = 0; i < snd_pcm_known_rates.count; i++)
512 		if ((1u << i) == rate_bit)
513 			return snd_pcm_known_rates.list[i];
514 	return 0;
515 }
516 EXPORT_SYMBOL(snd_pcm_rate_bit_to_rate);
517