xref: /openbmc/linux/sound/usb/format.c (revision c8ac8212)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  */
4 
5 #include <linux/init.h>
6 #include <linux/slab.h>
7 #include <linux/usb.h>
8 #include <linux/usb/audio.h>
9 #include <linux/usb/audio-v2.h>
10 #include <linux/usb/audio-v3.h>
11 
12 #include <sound/core.h>
13 #include <sound/pcm.h>
14 
15 #include "usbaudio.h"
16 #include "card.h"
17 #include "quirks.h"
18 #include "helper.h"
19 #include "debug.h"
20 #include "clock.h"
21 #include "format.h"
22 
23 /*
24  * parse the audio format type I descriptor
25  * and returns the corresponding pcm format
26  *
27  * @dev: usb device
28  * @fp: audioformat record
29  * @format: the format tag (wFormatTag)
30  * @fmt: the format type descriptor (v1/v2) or AudioStreaming descriptor (v3)
31  */
32 static u64 parse_audio_format_i_type(struct snd_usb_audio *chip,
33 				     struct audioformat *fp,
34 				     u64 format, void *_fmt)
35 {
36 	int sample_width, sample_bytes;
37 	u64 pcm_formats = 0;
38 
39 	switch (fp->protocol) {
40 	case UAC_VERSION_1:
41 	default: {
42 		struct uac_format_type_i_discrete_descriptor *fmt = _fmt;
43 		sample_width = fmt->bBitResolution;
44 		sample_bytes = fmt->bSubframeSize;
45 		format = 1ULL << format;
46 		break;
47 	}
48 
49 	case UAC_VERSION_2: {
50 		struct uac_format_type_i_ext_descriptor *fmt = _fmt;
51 		sample_width = fmt->bBitResolution;
52 		sample_bytes = fmt->bSubslotSize;
53 
54 		if (format & UAC2_FORMAT_TYPE_I_RAW_DATA) {
55 			pcm_formats |= SNDRV_PCM_FMTBIT_SPECIAL;
56 			/* flag potentially raw DSD capable altsettings */
57 			fp->dsd_raw = true;
58 		}
59 
60 		format <<= 1;
61 		break;
62 	}
63 	case UAC_VERSION_3: {
64 		struct uac3_as_header_descriptor *as = _fmt;
65 
66 		sample_width = as->bBitResolution;
67 		sample_bytes = as->bSubslotSize;
68 
69 		if (format & UAC3_FORMAT_TYPE_I_RAW_DATA)
70 			pcm_formats |= SNDRV_PCM_FMTBIT_SPECIAL;
71 
72 		format <<= 1;
73 		break;
74 	}
75 	}
76 
77 	fp->fmt_bits = sample_width;
78 
79 	if ((pcm_formats == 0) &&
80 	    (format == 0 || format == (1 << UAC_FORMAT_TYPE_I_UNDEFINED))) {
81 		/* some devices don't define this correctly... */
82 		usb_audio_info(chip, "%u:%d : format type 0 is detected, processed as PCM\n",
83 			fp->iface, fp->altsetting);
84 		format = 1 << UAC_FORMAT_TYPE_I_PCM;
85 	}
86 	if (format & (1 << UAC_FORMAT_TYPE_I_PCM)) {
87 		if (((chip->usb_id == USB_ID(0x0582, 0x0016)) ||
88 		     /* Edirol SD-90 */
89 		     (chip->usb_id == USB_ID(0x0582, 0x000c))) &&
90 		     /* Roland SC-D70 */
91 		    sample_width == 24 && sample_bytes == 2)
92 			sample_bytes = 3;
93 		else if (sample_width > sample_bytes * 8) {
94 			usb_audio_info(chip, "%u:%d : sample bitwidth %d in over sample bytes %d\n",
95 				 fp->iface, fp->altsetting,
96 				 sample_width, sample_bytes);
97 		}
98 		/* check the format byte size */
99 		switch (sample_bytes) {
100 		case 1:
101 			pcm_formats |= SNDRV_PCM_FMTBIT_S8;
102 			break;
103 		case 2:
104 			if (snd_usb_is_big_endian_format(chip, fp))
105 				pcm_formats |= SNDRV_PCM_FMTBIT_S16_BE; /* grrr, big endian!! */
106 			else
107 				pcm_formats |= SNDRV_PCM_FMTBIT_S16_LE;
108 			break;
109 		case 3:
110 			if (snd_usb_is_big_endian_format(chip, fp))
111 				pcm_formats |= SNDRV_PCM_FMTBIT_S24_3BE; /* grrr, big endian!! */
112 			else
113 				pcm_formats |= SNDRV_PCM_FMTBIT_S24_3LE;
114 			break;
115 		case 4:
116 			pcm_formats |= SNDRV_PCM_FMTBIT_S32_LE;
117 			break;
118 		default:
119 			usb_audio_info(chip,
120 				 "%u:%d : unsupported sample bitwidth %d in %d bytes\n",
121 				 fp->iface, fp->altsetting,
122 				 sample_width, sample_bytes);
123 			break;
124 		}
125 	}
126 	if (format & (1 << UAC_FORMAT_TYPE_I_PCM8)) {
127 		/* Dallas DS4201 workaround: it advertises U8 format, but really
128 		   supports S8. */
129 		if (chip->usb_id == USB_ID(0x04fa, 0x4201))
130 			pcm_formats |= SNDRV_PCM_FMTBIT_S8;
131 		else
132 			pcm_formats |= SNDRV_PCM_FMTBIT_U8;
133 	}
134 	if (format & (1 << UAC_FORMAT_TYPE_I_IEEE_FLOAT)) {
135 		pcm_formats |= SNDRV_PCM_FMTBIT_FLOAT_LE;
136 	}
137 	if (format & (1 << UAC_FORMAT_TYPE_I_ALAW)) {
138 		pcm_formats |= SNDRV_PCM_FMTBIT_A_LAW;
139 	}
140 	if (format & (1 << UAC_FORMAT_TYPE_I_MULAW)) {
141 		pcm_formats |= SNDRV_PCM_FMTBIT_MU_LAW;
142 	}
143 	if (format & ~0x3f) {
144 		usb_audio_info(chip,
145 			 "%u:%d : unsupported format bits %#llx\n",
146 			 fp->iface, fp->altsetting, format);
147 	}
148 
149 	pcm_formats |= snd_usb_interface_dsd_format_quirks(chip, fp, sample_bytes);
150 
151 	return pcm_formats;
152 }
153 
154 static int set_fixed_rate(struct audioformat *fp, int rate, int rate_bits)
155 {
156 	kfree(fp->rate_table);
157 	fp->rate_table = kmalloc(sizeof(int), GFP_KERNEL);
158 	if (!fp->rate_table)
159 		return -ENOMEM;
160 	fp->nr_rates = 1;
161 	fp->rate_min = rate;
162 	fp->rate_max = rate;
163 	fp->rates = rate_bits;
164 	fp->rate_table[0] = rate;
165 	return 0;
166 }
167 
168 /*
169  * parse the format descriptor and stores the possible sample rates
170  * on the audioformat table (audio class v1).
171  *
172  * @dev: usb device
173  * @fp: audioformat record
174  * @fmt: the format descriptor
175  * @offset: the start offset of descriptor pointing the rate type
176  *          (7 for type I and II, 8 for type II)
177  */
178 static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audioformat *fp,
179 				       unsigned char *fmt, int offset)
180 {
181 	int nr_rates = fmt[offset];
182 
183 	if (fmt[0] < offset + 1 + 3 * (nr_rates ? nr_rates : 2)) {
184 		usb_audio_err(chip,
185 			"%u:%d : invalid UAC_FORMAT_TYPE desc\n",
186 			fp->iface, fp->altsetting);
187 		return -EINVAL;
188 	}
189 
190 	if (nr_rates) {
191 		/*
192 		 * build the rate table and bitmap flags
193 		 */
194 		int r, idx;
195 
196 		fp->rate_table = kmalloc_array(nr_rates, sizeof(int),
197 					       GFP_KERNEL);
198 		if (fp->rate_table == NULL)
199 			return -ENOMEM;
200 
201 		fp->nr_rates = 0;
202 		fp->rate_min = fp->rate_max = 0;
203 		for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
204 			unsigned int rate = combine_triple(&fmt[idx]);
205 			if (!rate)
206 				continue;
207 			/* C-Media CM6501 mislabels its 96 kHz altsetting */
208 			/* Terratec Aureon 7.1 USB C-Media 6206, too */
209 			if (rate == 48000 && nr_rates == 1 &&
210 			    (chip->usb_id == USB_ID(0x0d8c, 0x0201) ||
211 			     chip->usb_id == USB_ID(0x0d8c, 0x0102) ||
212 			     chip->usb_id == USB_ID(0x0ccd, 0x00b1)) &&
213 			    fp->altsetting == 5 && fp->maxpacksize == 392)
214 				rate = 96000;
215 			/* Creative VF0420/VF0470 Live Cams report 16 kHz instead of 8kHz */
216 			if (rate == 16000 &&
217 			    (chip->usb_id == USB_ID(0x041e, 0x4064) ||
218 			     chip->usb_id == USB_ID(0x041e, 0x4068)))
219 				rate = 8000;
220 
221 			fp->rate_table[fp->nr_rates] = rate;
222 			if (!fp->rate_min || rate < fp->rate_min)
223 				fp->rate_min = rate;
224 			if (!fp->rate_max || rate > fp->rate_max)
225 				fp->rate_max = rate;
226 			fp->rates |= snd_pcm_rate_to_rate_bit(rate);
227 			fp->nr_rates++;
228 		}
229 		if (!fp->nr_rates) {
230 			hwc_debug("All rates were zero. Skipping format!\n");
231 			return -EINVAL;
232 		}
233 	} else {
234 		/* continuous rates */
235 		fp->rates = SNDRV_PCM_RATE_CONTINUOUS;
236 		fp->rate_min = combine_triple(&fmt[offset + 1]);
237 		fp->rate_max = combine_triple(&fmt[offset + 4]);
238 	}
239 
240 	/* Jabra Evolve 65 headset */
241 	if (chip->usb_id == USB_ID(0x0b0e, 0x030b)) {
242 		/* only 48kHz for playback while keeping 16kHz for capture */
243 		if (fp->nr_rates != 1)
244 			return set_fixed_rate(fp, 48000, SNDRV_PCM_RATE_48000);
245 	}
246 
247 	return 0;
248 }
249 
250 /*
251  * Helper function to walk the array of sample rate triplets reported by
252  * the device. The problem is that we need to parse whole array first to
253  * get to know how many sample rates we have to expect.
254  * Then fp->rate_table can be allocated and filled.
255  */
256 static int parse_uac2_sample_rate_range(struct snd_usb_audio *chip,
257 					struct audioformat *fp, int nr_triplets,
258 					const unsigned char *data)
259 {
260 	int i, nr_rates = 0;
261 
262 	fp->rates = fp->rate_min = fp->rate_max = 0;
263 
264 	for (i = 0; i < nr_triplets; i++) {
265 		int min = combine_quad(&data[2 + 12 * i]);
266 		int max = combine_quad(&data[6 + 12 * i]);
267 		int res = combine_quad(&data[10 + 12 * i]);
268 		unsigned int rate;
269 
270 		if ((max < 0) || (min < 0) || (res < 0) || (max < min))
271 			continue;
272 
273 		/*
274 		 * for ranges with res == 1, we announce a continuous sample
275 		 * rate range, and this function should return 0 for no further
276 		 * parsing.
277 		 */
278 		if (res == 1) {
279 			fp->rate_min = min;
280 			fp->rate_max = max;
281 			fp->rates = SNDRV_PCM_RATE_CONTINUOUS;
282 			return 0;
283 		}
284 
285 		for (rate = min; rate <= max; rate += res) {
286 			if (fp->rate_table)
287 				fp->rate_table[nr_rates] = rate;
288 			if (!fp->rate_min || rate < fp->rate_min)
289 				fp->rate_min = rate;
290 			if (!fp->rate_max || rate > fp->rate_max)
291 				fp->rate_max = rate;
292 			fp->rates |= snd_pcm_rate_to_rate_bit(rate);
293 
294 			nr_rates++;
295 			if (nr_rates >= MAX_NR_RATES) {
296 				usb_audio_err(chip, "invalid uac2 rates\n");
297 				break;
298 			}
299 
300 			/* avoid endless loop */
301 			if (res == 0)
302 				break;
303 		}
304 	}
305 
306 	return nr_rates;
307 }
308 
309 /* Line6 Helix series don't support the UAC2_CS_RANGE usb function
310  * call. Return a static table of known clock rates.
311  */
312 static int line6_parse_audio_format_rates_quirk(struct snd_usb_audio *chip,
313 						struct audioformat *fp)
314 {
315 	switch (chip->usb_id) {
316 	case USB_ID(0x0e41, 0x4241): /* Line6 Helix */
317 	case USB_ID(0x0e41, 0x4242): /* Line6 Helix Rack */
318 	case USB_ID(0x0e41, 0x4244): /* Line6 Helix LT */
319 	case USB_ID(0x0e41, 0x4246): /* Line6 HX-Stomp */
320 	case USB_ID(0x0e41, 0x4248): /* Line6 Helix >= fw 2.82 */
321 	case USB_ID(0x0e41, 0x4249): /* Line6 Helix Rack >= fw 2.82 */
322 	case USB_ID(0x0e41, 0x424a): /* Line6 Helix LT >= fw 2.82 */
323 		return set_fixed_rate(fp, 48000, SNDRV_PCM_RATE_48000);
324 	}
325 
326 	return -ENODEV;
327 }
328 
329 /*
330  * parse the format descriptor and stores the possible sample rates
331  * on the audioformat table (audio class v2 and v3).
332  */
333 static int parse_audio_format_rates_v2v3(struct snd_usb_audio *chip,
334 				       struct audioformat *fp)
335 {
336 	struct usb_device *dev = chip->dev;
337 	unsigned char tmp[2], *data;
338 	int nr_triplets, data_size, ret = 0, ret_l6;
339 	int clock = snd_usb_clock_find_source(chip, fp, false);
340 
341 	if (clock < 0) {
342 		dev_err(&dev->dev,
343 			"%s(): unable to find clock source (clock %d)\n",
344 				__func__, clock);
345 		goto err;
346 	}
347 
348 	/* get the number of sample rates first by only fetching 2 bytes */
349 	ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_RANGE,
350 			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
351 			      UAC2_CS_CONTROL_SAM_FREQ << 8,
352 			      snd_usb_ctrl_intf(chip) | (clock << 8),
353 			      tmp, sizeof(tmp));
354 
355 	if (ret < 0) {
356 		/* line6 helix devices don't support UAC2_CS_CONTROL_SAM_FREQ call */
357 		ret_l6 = line6_parse_audio_format_rates_quirk(chip, fp);
358 		if (ret_l6 == -ENODEV) {
359 			/* no line6 device found continue showing the error */
360 			dev_err(&dev->dev,
361 				"%s(): unable to retrieve number of sample rates (clock %d)\n",
362 				__func__, clock);
363 			goto err;
364 		}
365 		if (ret_l6 == 0) {
366 			dev_info(&dev->dev,
367 				"%s(): unable to retrieve number of sample rates: set it to a predefined value (clock %d).\n",
368 				__func__, clock);
369 			return 0;
370 		}
371 		ret = ret_l6;
372 		goto err;
373 	}
374 
375 	nr_triplets = (tmp[1] << 8) | tmp[0];
376 	data_size = 2 + 12 * nr_triplets;
377 	data = kzalloc(data_size, GFP_KERNEL);
378 	if (!data) {
379 		ret = -ENOMEM;
380 		goto err;
381 	}
382 
383 	/* now get the full information */
384 	ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_RANGE,
385 			      USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
386 			      UAC2_CS_CONTROL_SAM_FREQ << 8,
387 			      snd_usb_ctrl_intf(chip) | (clock << 8),
388 			      data, data_size);
389 
390 	if (ret < 0) {
391 		dev_err(&dev->dev,
392 			"%s(): unable to retrieve sample rate range (clock %d)\n",
393 				__func__, clock);
394 		ret = -EINVAL;
395 		goto err_free;
396 	}
397 
398 	/* Call the triplet parser, and make sure fp->rate_table is NULL.
399 	 * We just use the return value to know how many sample rates we
400 	 * will have to deal with. */
401 	kfree(fp->rate_table);
402 	fp->rate_table = NULL;
403 	fp->nr_rates = parse_uac2_sample_rate_range(chip, fp, nr_triplets, data);
404 
405 	if (fp->nr_rates == 0) {
406 		/* SNDRV_PCM_RATE_CONTINUOUS */
407 		ret = 0;
408 		goto err_free;
409 	}
410 
411 	fp->rate_table = kmalloc_array(fp->nr_rates, sizeof(int), GFP_KERNEL);
412 	if (!fp->rate_table) {
413 		ret = -ENOMEM;
414 		goto err_free;
415 	}
416 
417 	/* Call the triplet parser again, but this time, fp->rate_table is
418 	 * allocated, so the rates will be stored */
419 	parse_uac2_sample_rate_range(chip, fp, nr_triplets, data);
420 
421 err_free:
422 	kfree(data);
423 err:
424 	return ret;
425 }
426 
427 /*
428  * parse the format type I and III descriptors
429  */
430 static int parse_audio_format_i(struct snd_usb_audio *chip,
431 				struct audioformat *fp, u64 format,
432 				void *_fmt)
433 {
434 	snd_pcm_format_t pcm_format;
435 	unsigned int fmt_type;
436 	int ret;
437 
438 	switch (fp->protocol) {
439 	default:
440 	case UAC_VERSION_1:
441 	case UAC_VERSION_2: {
442 		struct uac_format_type_i_continuous_descriptor *fmt = _fmt;
443 
444 		fmt_type = fmt->bFormatType;
445 		break;
446 	}
447 	case UAC_VERSION_3: {
448 		/* fp->fmt_type is already set in this case */
449 		fmt_type = fp->fmt_type;
450 		break;
451 	}
452 	}
453 
454 	if (fmt_type == UAC_FORMAT_TYPE_III) {
455 		/* FIXME: the format type is really IECxxx
456 		 *        but we give normal PCM format to get the existing
457 		 *        apps working...
458 		 */
459 		switch (chip->usb_id) {
460 
461 		case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
462 			if (chip->setup == 0x00 &&
463 			    fp->altsetting == 6)
464 				pcm_format = SNDRV_PCM_FORMAT_S16_BE;
465 			else
466 				pcm_format = SNDRV_PCM_FORMAT_S16_LE;
467 			break;
468 		default:
469 			pcm_format = SNDRV_PCM_FORMAT_S16_LE;
470 		}
471 		fp->formats = pcm_format_to_bits(pcm_format);
472 	} else {
473 		fp->formats = parse_audio_format_i_type(chip, fp, format, _fmt);
474 		if (!fp->formats)
475 			return -EINVAL;
476 	}
477 
478 	/* gather possible sample rates */
479 	/* audio class v1 reports possible sample rates as part of the
480 	 * proprietary class specific descriptor.
481 	 * audio class v2 uses class specific EP0 range requests for that.
482 	 */
483 	switch (fp->protocol) {
484 	default:
485 	case UAC_VERSION_1: {
486 		struct uac_format_type_i_continuous_descriptor *fmt = _fmt;
487 
488 		fp->channels = fmt->bNrChannels;
489 		ret = parse_audio_format_rates_v1(chip, fp, (unsigned char *) fmt, 7);
490 		break;
491 	}
492 	case UAC_VERSION_2:
493 	case UAC_VERSION_3: {
494 		/* fp->channels is already set in this case */
495 		ret = parse_audio_format_rates_v2v3(chip, fp);
496 		break;
497 	}
498 	}
499 
500 	if (fp->channels < 1) {
501 		usb_audio_err(chip,
502 			"%u:%d : invalid channels %d\n",
503 			fp->iface, fp->altsetting, fp->channels);
504 		return -EINVAL;
505 	}
506 
507 	return ret;
508 }
509 
510 /*
511  * parse the format type II descriptor
512  */
513 static int parse_audio_format_ii(struct snd_usb_audio *chip,
514 				 struct audioformat *fp,
515 				 u64 format, void *_fmt)
516 {
517 	int brate, framesize, ret;
518 
519 	switch (format) {
520 	case UAC_FORMAT_TYPE_II_AC3:
521 		/* FIXME: there is no AC3 format defined yet */
522 		// fp->formats = SNDRV_PCM_FMTBIT_AC3;
523 		fp->formats = SNDRV_PCM_FMTBIT_U8; /* temporary hack to receive byte streams */
524 		break;
525 	case UAC_FORMAT_TYPE_II_MPEG:
526 		fp->formats = SNDRV_PCM_FMTBIT_MPEG;
527 		break;
528 	default:
529 		usb_audio_info(chip,
530 			 "%u:%d : unknown format tag %#llx is detected.  processed as MPEG.\n",
531 			 fp->iface, fp->altsetting, format);
532 		fp->formats = SNDRV_PCM_FMTBIT_MPEG;
533 		break;
534 	}
535 
536 	fp->channels = 1;
537 
538 	switch (fp->protocol) {
539 	default:
540 	case UAC_VERSION_1: {
541 		struct uac_format_type_ii_discrete_descriptor *fmt = _fmt;
542 		brate = le16_to_cpu(fmt->wMaxBitRate);
543 		framesize = le16_to_cpu(fmt->wSamplesPerFrame);
544 		usb_audio_info(chip, "found format II with max.bitrate = %d, frame size=%d\n", brate, framesize);
545 		fp->frame_size = framesize;
546 		ret = parse_audio_format_rates_v1(chip, fp, _fmt, 8); /* fmt[8..] sample rates */
547 		break;
548 	}
549 	case UAC_VERSION_2: {
550 		struct uac_format_type_ii_ext_descriptor *fmt = _fmt;
551 		brate = le16_to_cpu(fmt->wMaxBitRate);
552 		framesize = le16_to_cpu(fmt->wSamplesPerFrame);
553 		usb_audio_info(chip, "found format II with max.bitrate = %d, frame size=%d\n", brate, framesize);
554 		fp->frame_size = framesize;
555 		ret = parse_audio_format_rates_v2v3(chip, fp);
556 		break;
557 	}
558 	}
559 
560 	return ret;
561 }
562 
563 int snd_usb_parse_audio_format(struct snd_usb_audio *chip,
564 			       struct audioformat *fp, u64 format,
565 			       struct uac_format_type_i_continuous_descriptor *fmt,
566 			       int stream)
567 {
568 	int err;
569 
570 	switch (fmt->bFormatType) {
571 	case UAC_FORMAT_TYPE_I:
572 	case UAC_FORMAT_TYPE_III:
573 		err = parse_audio_format_i(chip, fp, format, fmt);
574 		break;
575 	case UAC_FORMAT_TYPE_II:
576 		err = parse_audio_format_ii(chip, fp, format, fmt);
577 		break;
578 	default:
579 		usb_audio_info(chip,
580 			 "%u:%d : format type %d is not supported yet\n",
581 			 fp->iface, fp->altsetting,
582 			 fmt->bFormatType);
583 		return -ENOTSUPP;
584 	}
585 	fp->fmt_type = fmt->bFormatType;
586 	if (err < 0)
587 		return err;
588 #if 1
589 	/* FIXME: temporary hack for extigy/audigy 2 nx/zs */
590 	/* extigy apparently supports sample rates other than 48k
591 	 * but not in ordinary way.  so we enable only 48k atm.
592 	 */
593 	if (chip->usb_id == USB_ID(0x041e, 0x3000) ||
594 	    chip->usb_id == USB_ID(0x041e, 0x3020) ||
595 	    chip->usb_id == USB_ID(0x041e, 0x3061)) {
596 		if (fmt->bFormatType == UAC_FORMAT_TYPE_I &&
597 		    fp->rates != SNDRV_PCM_RATE_48000 &&
598 		    fp->rates != SNDRV_PCM_RATE_96000)
599 			return -ENOTSUPP;
600 	}
601 #endif
602 	return 0;
603 }
604 
605 int snd_usb_parse_audio_format_v3(struct snd_usb_audio *chip,
606 			       struct audioformat *fp,
607 			       struct uac3_as_header_descriptor *as,
608 			       int stream)
609 {
610 	u64 format = le64_to_cpu(as->bmFormats);
611 	int err;
612 
613 	/*
614 	 * Type I format bits are D0..D6
615 	 * This test works because type IV is not supported
616 	 */
617 	if (format & 0x7f)
618 		fp->fmt_type = UAC_FORMAT_TYPE_I;
619 	else
620 		fp->fmt_type = UAC_FORMAT_TYPE_III;
621 
622 	err = parse_audio_format_i(chip, fp, format, as);
623 	if (err < 0)
624 		return err;
625 
626 	return 0;
627 }
628