xref: /linux/sound/usb/mixer.c (revision 8ab2e96d8ff188006f1e3346a56443cd07fe1858)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   (Tentative) USB Audio Driver for ALSA
4  *
5  *   Mixer control part
6  *
7  *   Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
8  *
9  *   Many codes borrowed from audio.c by
10  *	    Alan Cox (alan@lxorguk.ukuu.org.uk)
11  *	    Thomas Sailer (sailer@ife.ee.ethz.ch)
12  */
13 
14 /*
15  * TODOs, for both the mixer and the streaming interfaces:
16  *
17  *  - support for UAC2 effect units
18  *  - support for graphical equalizers
19  *  - RANGE and MEM set commands (UAC2)
20  *  - RANGE and MEM interrupt dispatchers (UAC2)
21  *  - audio channel clustering (UAC2)
22  *  - audio sample rate converter units (UAC2)
23  *  - proper handling of clock multipliers (UAC2)
24  *  - dispatch clock change notifications (UAC2)
25  *  	- stop PCM streams which use a clock that became invalid
26  *  	- stop PCM streams which use a clock selector that has changed
27  *  	- parse available sample rates again when clock sources changed
28  */
29 
30 #include <linux/bitops.h>
31 #include <linux/init.h>
32 #include <linux/list.h>
33 #include <linux/log2.h>
34 #include <linux/slab.h>
35 #include <linux/string.h>
36 #include <linux/usb.h>
37 #include <linux/usb/audio.h>
38 #include <linux/usb/audio-v2.h>
39 #include <linux/usb/audio-v3.h>
40 
41 #include <sound/core.h>
42 #include <sound/control.h>
43 #include <sound/hwdep.h>
44 #include <sound/info.h>
45 #include <sound/tlv.h>
46 
47 #include "usbaudio.h"
48 #include "mixer.h"
49 #include "helper.h"
50 #include "mixer_quirks.h"
51 #include "power.h"
52 
53 #define MAX_ID_ELEMS	256
54 
55 struct usb_audio_term {
56 	int id;
57 	int type;
58 	int channels;
59 	unsigned int chconfig;
60 	int name;
61 };
62 
63 struct usbmix_name_map;
64 
65 struct mixer_build {
66 	struct snd_usb_audio *chip;
67 	struct usb_mixer_interface *mixer;
68 	unsigned char *buffer;
69 	unsigned int buflen;
70 	DECLARE_BITMAP(unitbitmap, MAX_ID_ELEMS);
71 	DECLARE_BITMAP(termbitmap, MAX_ID_ELEMS);
72 	struct usb_audio_term oterm;
73 	const struct usbmix_name_map *map;
74 	const struct usbmix_selector_map *selector_map;
75 };
76 
77 /*E-mu 0202/0404/0204 eXtension Unit(XU) control*/
78 enum {
79 	USB_XU_CLOCK_RATE 		= 0xe301,
80 	USB_XU_CLOCK_SOURCE		= 0xe302,
81 	USB_XU_DIGITAL_IO_STATUS	= 0xe303,
82 	USB_XU_DEVICE_OPTIONS		= 0xe304,
83 	USB_XU_DIRECT_MONITORING	= 0xe305,
84 	USB_XU_METERING			= 0xe306
85 };
86 enum {
87 	USB_XU_CLOCK_SOURCE_SELECTOR = 0x02,	/* clock source*/
88 	USB_XU_CLOCK_RATE_SELECTOR = 0x03,	/* clock rate */
89 	USB_XU_DIGITAL_FORMAT_SELECTOR = 0x01,	/* the spdif format */
90 	USB_XU_SOFT_LIMIT_SELECTOR = 0x03	/* soft limiter */
91 };
92 
93 /*
94  * manual mapping of mixer names
95  * if the mixer topology is too complicated and the parsed names are
96  * ambiguous, add the entries in usbmixer_maps.c.
97  */
98 #include "mixer_maps.c"
99 
100 static const struct usbmix_name_map *
101 find_map(const struct usbmix_name_map *p, int unitid, int control)
102 {
103 	if (!p)
104 		return NULL;
105 
106 	for (; p->id; p++) {
107 		if (p->id == unitid &&
108 		    (!control || !p->control || control == p->control))
109 			return p;
110 	}
111 	return NULL;
112 }
113 
114 /* get the mapped name if the unit matches */
115 static int
116 check_mapped_name(const struct usbmix_name_map *p, char *buf, int buflen)
117 {
118 	if (!p || !p->name)
119 		return 0;
120 
121 	buflen--;
122 	return strlcpy(buf, p->name, buflen);
123 }
124 
125 /* ignore the error value if ignore_ctl_error flag is set */
126 #define filter_error(cval, err) \
127 	((cval)->head.mixer->ignore_ctl_error ? 0 : (err))
128 
129 /* check whether the control should be ignored */
130 static inline int
131 check_ignored_ctl(const struct usbmix_name_map *p)
132 {
133 	if (!p || p->name || p->dB)
134 		return 0;
135 	return 1;
136 }
137 
138 /* dB mapping */
139 static inline void check_mapped_dB(const struct usbmix_name_map *p,
140 				   struct usb_mixer_elem_info *cval)
141 {
142 	if (p && p->dB) {
143 		cval->dBmin = p->dB->min;
144 		cval->dBmax = p->dB->max;
145 		cval->initialized = 1;
146 	}
147 }
148 
149 /* get the mapped selector source name */
150 static int check_mapped_selector_name(struct mixer_build *state, int unitid,
151 				      int index, char *buf, int buflen)
152 {
153 	const struct usbmix_selector_map *p;
154 
155 	if (!state->selector_map)
156 		return 0;
157 	for (p = state->selector_map; p->id; p++) {
158 		if (p->id == unitid && index < p->count)
159 			return strlcpy(buf, p->names[index], buflen);
160 	}
161 	return 0;
162 }
163 
164 /*
165  * find an audio control unit with the given unit id
166  */
167 static void *find_audio_control_unit(struct mixer_build *state,
168 				     unsigned char unit)
169 {
170 	/* we just parse the header */
171 	struct uac_feature_unit_descriptor *hdr = NULL;
172 
173 	while ((hdr = snd_usb_find_desc(state->buffer, state->buflen, hdr,
174 					USB_DT_CS_INTERFACE)) != NULL) {
175 		if (hdr->bLength >= 4 &&
176 		    hdr->bDescriptorSubtype >= UAC_INPUT_TERMINAL &&
177 		    hdr->bDescriptorSubtype <= UAC3_SAMPLE_RATE_CONVERTER &&
178 		    hdr->bUnitID == unit)
179 			return hdr;
180 	}
181 
182 	return NULL;
183 }
184 
185 /*
186  * copy a string with the given id
187  */
188 static int snd_usb_copy_string_desc(struct snd_usb_audio *chip,
189 				    int index, char *buf, int maxlen)
190 {
191 	int len = usb_string(chip->dev, index, buf, maxlen - 1);
192 
193 	if (len < 0)
194 		return 0;
195 
196 	buf[len] = 0;
197 	return len;
198 }
199 
200 /*
201  * convert from the byte/word on usb descriptor to the zero-based integer
202  */
203 static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
204 {
205 	switch (cval->val_type) {
206 	case USB_MIXER_BOOLEAN:
207 		return !!val;
208 	case USB_MIXER_INV_BOOLEAN:
209 		return !val;
210 	case USB_MIXER_U8:
211 		val &= 0xff;
212 		break;
213 	case USB_MIXER_S8:
214 		val &= 0xff;
215 		if (val >= 0x80)
216 			val -= 0x100;
217 		break;
218 	case USB_MIXER_U16:
219 		val &= 0xffff;
220 		break;
221 	case USB_MIXER_S16:
222 		val &= 0xffff;
223 		if (val >= 0x8000)
224 			val -= 0x10000;
225 		break;
226 	}
227 	return val;
228 }
229 
230 /*
231  * convert from the zero-based int to the byte/word for usb descriptor
232  */
233 static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
234 {
235 	switch (cval->val_type) {
236 	case USB_MIXER_BOOLEAN:
237 		return !!val;
238 	case USB_MIXER_INV_BOOLEAN:
239 		return !val;
240 	case USB_MIXER_S8:
241 	case USB_MIXER_U8:
242 		return val & 0xff;
243 	case USB_MIXER_S16:
244 	case USB_MIXER_U16:
245 		return val & 0xffff;
246 	}
247 	return 0; /* not reached */
248 }
249 
250 static int get_relative_value(struct usb_mixer_elem_info *cval, int val)
251 {
252 	if (!cval->res)
253 		cval->res = 1;
254 	if (val < cval->min)
255 		return 0;
256 	else if (val >= cval->max)
257 		return (cval->max - cval->min + cval->res - 1) / cval->res;
258 	else
259 		return (val - cval->min) / cval->res;
260 }
261 
262 static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
263 {
264 	if (val < 0)
265 		return cval->min;
266 	if (!cval->res)
267 		cval->res = 1;
268 	val *= cval->res;
269 	val += cval->min;
270 	if (val > cval->max)
271 		return cval->max;
272 	return val;
273 }
274 
275 static int uac2_ctl_value_size(int val_type)
276 {
277 	switch (val_type) {
278 	case USB_MIXER_S32:
279 	case USB_MIXER_U32:
280 		return 4;
281 	case USB_MIXER_S16:
282 	case USB_MIXER_U16:
283 		return 2;
284 	default:
285 		return 1;
286 	}
287 	return 0; /* unreachable */
288 }
289 
290 
291 /*
292  * retrieve a mixer value
293  */
294 
295 static inline int mixer_ctrl_intf(struct usb_mixer_interface *mixer)
296 {
297 	return get_iface_desc(mixer->hostif)->bInterfaceNumber;
298 }
299 
300 static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request,
301 			    int validx, int *value_ret)
302 {
303 	struct snd_usb_audio *chip = cval->head.mixer->chip;
304 	unsigned char buf[2];
305 	int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
306 	int timeout = 10;
307 	int idx = 0, err;
308 
309 	err = snd_usb_lock_shutdown(chip);
310 	if (err < 0)
311 		return -EIO;
312 
313 	while (timeout-- > 0) {
314 		idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
315 		err = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
316 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
317 				      validx, idx, buf, val_len);
318 		if (err >= val_len) {
319 			*value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
320 			err = 0;
321 			goto out;
322 		} else if (err == -ETIMEDOUT) {
323 			goto out;
324 		}
325 	}
326 	usb_audio_dbg(chip,
327 		"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
328 		request, validx, idx, cval->val_type);
329 	err = -EINVAL;
330 
331  out:
332 	snd_usb_unlock_shutdown(chip);
333 	return err;
334 }
335 
336 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
337 			    int validx, int *value_ret)
338 {
339 	struct snd_usb_audio *chip = cval->head.mixer->chip;
340 	/* enough space for one range */
341 	unsigned char buf[sizeof(__u16) + 3 * sizeof(__u32)];
342 	unsigned char *val;
343 	int idx = 0, ret, val_size, size;
344 	__u8 bRequest;
345 
346 	val_size = uac2_ctl_value_size(cval->val_type);
347 
348 	if (request == UAC_GET_CUR) {
349 		bRequest = UAC2_CS_CUR;
350 		size = val_size;
351 	} else {
352 		bRequest = UAC2_CS_RANGE;
353 		size = sizeof(__u16) + 3 * val_size;
354 	}
355 
356 	memset(buf, 0, sizeof(buf));
357 
358 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
359 	if (ret)
360 		goto error;
361 
362 	idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
363 	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
364 			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
365 			      validx, idx, buf, size);
366 	snd_usb_unlock_shutdown(chip);
367 
368 	if (ret < 0) {
369 error:
370 		usb_audio_err(chip,
371 			"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
372 			request, validx, idx, cval->val_type);
373 		return ret;
374 	}
375 
376 	/* FIXME: how should we handle multiple triplets here? */
377 
378 	switch (request) {
379 	case UAC_GET_CUR:
380 		val = buf;
381 		break;
382 	case UAC_GET_MIN:
383 		val = buf + sizeof(__u16);
384 		break;
385 	case UAC_GET_MAX:
386 		val = buf + sizeof(__u16) + val_size;
387 		break;
388 	case UAC_GET_RES:
389 		val = buf + sizeof(__u16) + val_size * 2;
390 		break;
391 	default:
392 		return -EINVAL;
393 	}
394 
395 	*value_ret = convert_signed_value(cval,
396 					  snd_usb_combine_bytes(val, val_size));
397 
398 	return 0;
399 }
400 
401 static int get_ctl_value(struct usb_mixer_elem_info *cval, int request,
402 			 int validx, int *value_ret)
403 {
404 	validx += cval->idx_off;
405 
406 	return (cval->head.mixer->protocol == UAC_VERSION_1) ?
407 		get_ctl_value_v1(cval, request, validx, value_ret) :
408 		get_ctl_value_v2(cval, request, validx, value_ret);
409 }
410 
411 static int get_cur_ctl_value(struct usb_mixer_elem_info *cval,
412 			     int validx, int *value)
413 {
414 	return get_ctl_value(cval, UAC_GET_CUR, validx, value);
415 }
416 
417 /* channel = 0: master, 1 = first channel */
418 static inline int get_cur_mix_raw(struct usb_mixer_elem_info *cval,
419 				  int channel, int *value)
420 {
421 	return get_ctl_value(cval, UAC_GET_CUR,
422 			     (cval->control << 8) | channel,
423 			     value);
424 }
425 
426 int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
427 			     int channel, int index, int *value)
428 {
429 	int err;
430 
431 	if (cval->cached & (1 << channel)) {
432 		*value = cval->cache_val[index];
433 		return 0;
434 	}
435 	err = get_cur_mix_raw(cval, channel, value);
436 	if (err < 0) {
437 		if (!cval->head.mixer->ignore_ctl_error)
438 			usb_audio_dbg(cval->head.mixer->chip,
439 				"cannot get current value for control %d ch %d: err = %d\n",
440 				      cval->control, channel, err);
441 		return err;
442 	}
443 	cval->cached |= 1 << channel;
444 	cval->cache_val[index] = *value;
445 	return 0;
446 }
447 
448 /*
449  * set a mixer value
450  */
451 
452 int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
453 				int request, int validx, int value_set)
454 {
455 	struct snd_usb_audio *chip = cval->head.mixer->chip;
456 	unsigned char buf[4];
457 	int idx = 0, val_len, err, timeout = 10;
458 
459 	validx += cval->idx_off;
460 
461 
462 	if (cval->head.mixer->protocol == UAC_VERSION_1) {
463 		val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
464 	} else { /* UAC_VERSION_2/3 */
465 		val_len = uac2_ctl_value_size(cval->val_type);
466 
467 		/* FIXME */
468 		if (request != UAC_SET_CUR) {
469 			usb_audio_dbg(chip, "RANGE setting not yet supported\n");
470 			return -EINVAL;
471 		}
472 
473 		request = UAC2_CS_CUR;
474 	}
475 
476 	value_set = convert_bytes_value(cval, value_set);
477 	buf[0] = value_set & 0xff;
478 	buf[1] = (value_set >> 8) & 0xff;
479 	buf[2] = (value_set >> 16) & 0xff;
480 	buf[3] = (value_set >> 24) & 0xff;
481 
482 	err = snd_usb_lock_shutdown(chip);
483 	if (err < 0)
484 		return -EIO;
485 
486 	while (timeout-- > 0) {
487 		idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
488 		err = snd_usb_ctl_msg(chip->dev,
489 				      usb_sndctrlpipe(chip->dev, 0), request,
490 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
491 				      validx, idx, buf, val_len);
492 		if (err >= 0) {
493 			err = 0;
494 			goto out;
495 		} else if (err == -ETIMEDOUT) {
496 			goto out;
497 		}
498 	}
499 	usb_audio_dbg(chip, "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
500 		      request, validx, idx, cval->val_type, buf[0], buf[1]);
501 	err = -EINVAL;
502 
503  out:
504 	snd_usb_unlock_shutdown(chip);
505 	return err;
506 }
507 
508 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval,
509 			     int validx, int value)
510 {
511 	return snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, validx, value);
512 }
513 
514 int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
515 			     int index, int value)
516 {
517 	int err;
518 	unsigned int read_only = (channel == 0) ?
519 		cval->master_readonly :
520 		cval->ch_readonly & (1 << (channel - 1));
521 
522 	if (read_only) {
523 		usb_audio_dbg(cval->head.mixer->chip,
524 			      "%s(): channel %d of control %d is read_only\n",
525 			    __func__, channel, cval->control);
526 		return 0;
527 	}
528 
529 	err = snd_usb_mixer_set_ctl_value(cval,
530 					  UAC_SET_CUR, (cval->control << 8) | channel,
531 					  value);
532 	if (err < 0)
533 		return err;
534 	cval->cached |= 1 << channel;
535 	cval->cache_val[index] = value;
536 	return 0;
537 }
538 
539 /*
540  * TLV callback for mixer volume controls
541  */
542 int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
543 			 unsigned int size, unsigned int __user *_tlv)
544 {
545 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
546 	DECLARE_TLV_DB_MINMAX(scale, 0, 0);
547 
548 	if (size < sizeof(scale))
549 		return -ENOMEM;
550 	if (cval->min_mute)
551 		scale[0] = SNDRV_CTL_TLVT_DB_MINMAX_MUTE;
552 	scale[2] = cval->dBmin;
553 	scale[3] = cval->dBmax;
554 	if (copy_to_user(_tlv, scale, sizeof(scale)))
555 		return -EFAULT;
556 	return 0;
557 }
558 
559 /*
560  * parser routines begin here...
561  */
562 
563 static int parse_audio_unit(struct mixer_build *state, int unitid);
564 
565 
566 /*
567  * check if the input/output channel routing is enabled on the given bitmap.
568  * used for mixer unit parser
569  */
570 static int check_matrix_bitmap(unsigned char *bmap,
571 			       int ich, int och, int num_outs)
572 {
573 	int idx = ich * num_outs + och;
574 	return bmap[idx >> 3] & (0x80 >> (idx & 7));
575 }
576 
577 /*
578  * add an alsa control element
579  * search and increment the index until an empty slot is found.
580  *
581  * if failed, give up and free the control instance.
582  */
583 
584 int snd_usb_mixer_add_control(struct usb_mixer_elem_list *list,
585 			      struct snd_kcontrol *kctl)
586 {
587 	struct usb_mixer_interface *mixer = list->mixer;
588 	int err;
589 
590 	while (snd_ctl_find_id(mixer->chip->card, &kctl->id))
591 		kctl->id.index++;
592 	err = snd_ctl_add(mixer->chip->card, kctl);
593 	if (err < 0) {
594 		usb_audio_dbg(mixer->chip, "cannot add control (err = %d)\n",
595 			      err);
596 		return err;
597 	}
598 	list->kctl = kctl;
599 	list->next_id_elem = mixer->id_elems[list->id];
600 	mixer->id_elems[list->id] = list;
601 	return 0;
602 }
603 
604 /*
605  * get a terminal name string
606  */
607 
608 static struct iterm_name_combo {
609 	int type;
610 	char *name;
611 } iterm_names[] = {
612 	{ 0x0300, "Output" },
613 	{ 0x0301, "Speaker" },
614 	{ 0x0302, "Headphone" },
615 	{ 0x0303, "HMD Audio" },
616 	{ 0x0304, "Desktop Speaker" },
617 	{ 0x0305, "Room Speaker" },
618 	{ 0x0306, "Com Speaker" },
619 	{ 0x0307, "LFE" },
620 	{ 0x0600, "External In" },
621 	{ 0x0601, "Analog In" },
622 	{ 0x0602, "Digital In" },
623 	{ 0x0603, "Line" },
624 	{ 0x0604, "Legacy In" },
625 	{ 0x0605, "IEC958 In" },
626 	{ 0x0606, "1394 DA Stream" },
627 	{ 0x0607, "1394 DV Stream" },
628 	{ 0x0700, "Embedded" },
629 	{ 0x0701, "Noise Source" },
630 	{ 0x0702, "Equalization Noise" },
631 	{ 0x0703, "CD" },
632 	{ 0x0704, "DAT" },
633 	{ 0x0705, "DCC" },
634 	{ 0x0706, "MiniDisk" },
635 	{ 0x0707, "Analog Tape" },
636 	{ 0x0708, "Phonograph" },
637 	{ 0x0709, "VCR Audio" },
638 	{ 0x070a, "Video Disk Audio" },
639 	{ 0x070b, "DVD Audio" },
640 	{ 0x070c, "TV Tuner Audio" },
641 	{ 0x070d, "Satellite Rec Audio" },
642 	{ 0x070e, "Cable Tuner Audio" },
643 	{ 0x070f, "DSS Audio" },
644 	{ 0x0710, "Radio Receiver" },
645 	{ 0x0711, "Radio Transmitter" },
646 	{ 0x0712, "Multi-Track Recorder" },
647 	{ 0x0713, "Synthesizer" },
648 	{ 0 },
649 };
650 
651 static int get_term_name(struct snd_usb_audio *chip, struct usb_audio_term *iterm,
652 			 unsigned char *name, int maxlen, int term_only)
653 {
654 	struct iterm_name_combo *names;
655 	int len;
656 
657 	if (iterm->name) {
658 		len = snd_usb_copy_string_desc(chip, iterm->name,
659 						name, maxlen);
660 		if (len)
661 			return len;
662 	}
663 
664 	/* virtual type - not a real terminal */
665 	if (iterm->type >> 16) {
666 		if (term_only)
667 			return 0;
668 		switch (iterm->type >> 16) {
669 		case UAC3_SELECTOR_UNIT:
670 			strcpy(name, "Selector");
671 			return 8;
672 		case UAC3_PROCESSING_UNIT:
673 			strcpy(name, "Process Unit");
674 			return 12;
675 		case UAC3_EXTENSION_UNIT:
676 			strcpy(name, "Ext Unit");
677 			return 8;
678 		case UAC3_MIXER_UNIT:
679 			strcpy(name, "Mixer");
680 			return 5;
681 		default:
682 			return sprintf(name, "Unit %d", iterm->id);
683 		}
684 	}
685 
686 	switch (iterm->type & 0xff00) {
687 	case 0x0100:
688 		strcpy(name, "PCM");
689 		return 3;
690 	case 0x0200:
691 		strcpy(name, "Mic");
692 		return 3;
693 	case 0x0400:
694 		strcpy(name, "Headset");
695 		return 7;
696 	case 0x0500:
697 		strcpy(name, "Phone");
698 		return 5;
699 	}
700 
701 	for (names = iterm_names; names->type; names++) {
702 		if (names->type == iterm->type) {
703 			strcpy(name, names->name);
704 			return strlen(names->name);
705 		}
706 	}
707 
708 	return 0;
709 }
710 
711 /*
712  * Get logical cluster information for UAC3 devices.
713  */
714 static int get_cluster_channels_v3(struct mixer_build *state, unsigned int cluster_id)
715 {
716 	struct uac3_cluster_header_descriptor c_header;
717 	int err;
718 
719 	err = snd_usb_ctl_msg(state->chip->dev,
720 			usb_rcvctrlpipe(state->chip->dev, 0),
721 			UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
722 			USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
723 			cluster_id,
724 			snd_usb_ctrl_intf(state->chip),
725 			&c_header, sizeof(c_header));
726 	if (err < 0)
727 		goto error;
728 	if (err != sizeof(c_header)) {
729 		err = -EIO;
730 		goto error;
731 	}
732 
733 	return c_header.bNrChannels;
734 
735 error:
736 	usb_audio_err(state->chip, "cannot request logical cluster ID: %d (err: %d)\n", cluster_id, err);
737 	return err;
738 }
739 
740 /*
741  * Get number of channels for a Mixer Unit.
742  */
743 static int uac_mixer_unit_get_channels(struct mixer_build *state,
744 				       struct uac_mixer_unit_descriptor *desc)
745 {
746 	int mu_channels;
747 
748 	switch (state->mixer->protocol) {
749 	case UAC_VERSION_1:
750 	case UAC_VERSION_2:
751 	default:
752 		if (desc->bLength < sizeof(*desc) + desc->bNrInPins + 1)
753 			return 0; /* no bmControls -> skip */
754 		mu_channels = uac_mixer_unit_bNrChannels(desc);
755 		break;
756 	case UAC_VERSION_3:
757 		mu_channels = get_cluster_channels_v3(state,
758 				uac3_mixer_unit_wClusterDescrID(desc));
759 		break;
760 	}
761 
762 	return mu_channels;
763 }
764 
765 /*
766  * Parse Input Terminal Unit
767  */
768 static int __check_input_term(struct mixer_build *state, int id,
769 			      struct usb_audio_term *term);
770 
771 static int parse_term_uac1_iterm_unit(struct mixer_build *state,
772 				      struct usb_audio_term *term,
773 				      void *p1, int id)
774 {
775 	struct uac_input_terminal_descriptor *d = p1;
776 
777 	term->type = le16_to_cpu(d->wTerminalType);
778 	term->channels = d->bNrChannels;
779 	term->chconfig = le16_to_cpu(d->wChannelConfig);
780 	term->name = d->iTerminal;
781 	return 0;
782 }
783 
784 static int parse_term_uac2_iterm_unit(struct mixer_build *state,
785 				      struct usb_audio_term *term,
786 				      void *p1, int id)
787 {
788 	struct uac2_input_terminal_descriptor *d = p1;
789 	int err;
790 
791 	/* call recursively to verify the referenced clock entity */
792 	err = __check_input_term(state, d->bCSourceID, term);
793 	if (err < 0)
794 		return err;
795 
796 	/* save input term properties after recursion,
797 	 * to ensure they are not overriden by the recursion calls
798 	 */
799 	term->id = id;
800 	term->type = le16_to_cpu(d->wTerminalType);
801 	term->channels = d->bNrChannels;
802 	term->chconfig = le32_to_cpu(d->bmChannelConfig);
803 	term->name = d->iTerminal;
804 	return 0;
805 }
806 
807 static int parse_term_uac3_iterm_unit(struct mixer_build *state,
808 				      struct usb_audio_term *term,
809 				      void *p1, int id)
810 {
811 	struct uac3_input_terminal_descriptor *d = p1;
812 	int err;
813 
814 	/* call recursively to verify the referenced clock entity */
815 	err = __check_input_term(state, d->bCSourceID, term);
816 	if (err < 0)
817 		return err;
818 
819 	/* save input term properties after recursion,
820 	 * to ensure they are not overriden by the recursion calls
821 	 */
822 	term->id = id;
823 	term->type = le16_to_cpu(d->wTerminalType);
824 
825 	err = get_cluster_channels_v3(state, le16_to_cpu(d->wClusterDescrID));
826 	if (err < 0)
827 		return err;
828 	term->channels = err;
829 
830 	/* REVISIT: UAC3 IT doesn't have channels cfg */
831 	term->chconfig = 0;
832 
833 	term->name = le16_to_cpu(d->wTerminalDescrStr);
834 	return 0;
835 }
836 
837 static int parse_term_mixer_unit(struct mixer_build *state,
838 				 struct usb_audio_term *term,
839 				 void *p1, int id)
840 {
841 	struct uac_mixer_unit_descriptor *d = p1;
842 	int protocol = state->mixer->protocol;
843 	int err;
844 
845 	err = uac_mixer_unit_get_channels(state, d);
846 	if (err <= 0)
847 		return err;
848 
849 	term->type = UAC3_MIXER_UNIT << 16; /* virtual type */
850 	term->channels = err;
851 	if (protocol != UAC_VERSION_3) {
852 		term->chconfig = uac_mixer_unit_wChannelConfig(d, protocol);
853 		term->name = uac_mixer_unit_iMixer(d);
854 	}
855 	return 0;
856 }
857 
858 static int parse_term_selector_unit(struct mixer_build *state,
859 				    struct usb_audio_term *term,
860 				    void *p1, int id)
861 {
862 	struct uac_selector_unit_descriptor *d = p1;
863 	int err;
864 
865 	/* call recursively to retrieve the channel info */
866 	err = __check_input_term(state, d->baSourceID[0], term);
867 	if (err < 0)
868 		return err;
869 	term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */
870 	term->id = id;
871 	if (state->mixer->protocol != UAC_VERSION_3)
872 		term->name = uac_selector_unit_iSelector(d);
873 	return 0;
874 }
875 
876 static int parse_term_proc_unit(struct mixer_build *state,
877 				struct usb_audio_term *term,
878 				void *p1, int id, int vtype)
879 {
880 	struct uac_processing_unit_descriptor *d = p1;
881 	int protocol = state->mixer->protocol;
882 	int err;
883 
884 	if (d->bNrInPins) {
885 		/* call recursively to retrieve the channel info */
886 		err = __check_input_term(state, d->baSourceID[0], term);
887 		if (err < 0)
888 			return err;
889 	}
890 
891 	term->type = vtype << 16; /* virtual type */
892 	term->id = id;
893 
894 	if (protocol == UAC_VERSION_3)
895 		return 0;
896 
897 	if (!term->channels) {
898 		term->channels = uac_processing_unit_bNrChannels(d);
899 		term->chconfig = uac_processing_unit_wChannelConfig(d, protocol);
900 	}
901 	term->name = uac_processing_unit_iProcessing(d, protocol);
902 	return 0;
903 }
904 
905 static int parse_term_effect_unit(struct mixer_build *state,
906 				  struct usb_audio_term *term,
907 				  void *p1, int id)
908 {
909 	struct uac2_effect_unit_descriptor *d = p1;
910 	int err;
911 
912 	err = __check_input_term(state, d->bSourceID, term);
913 	if (err < 0)
914 		return err;
915 	term->type = UAC3_EFFECT_UNIT << 16; /* virtual type */
916 	term->id = id;
917 	return 0;
918 }
919 
920 static int parse_term_uac2_clock_source(struct mixer_build *state,
921 					struct usb_audio_term *term,
922 					void *p1, int id)
923 {
924 	struct uac_clock_source_descriptor *d = p1;
925 
926 	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
927 	term->id = id;
928 	term->name = d->iClockSource;
929 	return 0;
930 }
931 
932 static int parse_term_uac3_clock_source(struct mixer_build *state,
933 					struct usb_audio_term *term,
934 					void *p1, int id)
935 {
936 	struct uac3_clock_source_descriptor *d = p1;
937 
938 	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
939 	term->id = id;
940 	term->name = le16_to_cpu(d->wClockSourceStr);
941 	return 0;
942 }
943 
944 #define PTYPE(a, b)	((a) << 8 | (b))
945 
946 /*
947  * parse the source unit recursively until it reaches to a terminal
948  * or a branched unit.
949  */
950 static int __check_input_term(struct mixer_build *state, int id,
951 			      struct usb_audio_term *term)
952 {
953 	int protocol = state->mixer->protocol;
954 	void *p1;
955 	unsigned char *hdr;
956 
957 	for (;;) {
958 		/* a loop in the terminal chain? */
959 		if (test_and_set_bit(id, state->termbitmap))
960 			return -EINVAL;
961 
962 		p1 = find_audio_control_unit(state, id);
963 		if (!p1)
964 			break;
965 		if (!snd_usb_validate_audio_desc(p1, protocol))
966 			break; /* bad descriptor */
967 
968 		hdr = p1;
969 		term->id = id;
970 
971 		switch (PTYPE(protocol, hdr[2])) {
972 		case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):
973 		case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):
974 		case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT): {
975 			/* the header is the same for all versions */
976 			struct uac_feature_unit_descriptor *d = p1;
977 
978 			id = d->bSourceID;
979 			break; /* continue to parse */
980 		}
981 		case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):
982 			return parse_term_uac1_iterm_unit(state, term, p1, id);
983 		case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):
984 			return parse_term_uac2_iterm_unit(state, term, p1, id);
985 		case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):
986 			return parse_term_uac3_iterm_unit(state, term, p1, id);
987 		case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):
988 		case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):
989 		case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):
990 			return parse_term_mixer_unit(state, term, p1, id);
991 		case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):
992 		case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):
993 		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):
994 		case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):
995 		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):
996 			return parse_term_selector_unit(state, term, p1, id);
997 		case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):
998 		case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):
999 		case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):
1000 			return parse_term_proc_unit(state, term, p1, id,
1001 						    UAC3_PROCESSING_UNIT);
1002 		case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):
1003 		case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):
1004 			return parse_term_effect_unit(state, term, p1, id);
1005 		case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):
1006 		case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):
1007 		case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):
1008 			return parse_term_proc_unit(state, term, p1, id,
1009 						    UAC3_EXTENSION_UNIT);
1010 		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):
1011 			return parse_term_uac2_clock_source(state, term, p1, id);
1012 		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):
1013 			return parse_term_uac3_clock_source(state, term, p1, id);
1014 		default:
1015 			return -ENODEV;
1016 		}
1017 	}
1018 	return -ENODEV;
1019 }
1020 
1021 
1022 static int check_input_term(struct mixer_build *state, int id,
1023 			    struct usb_audio_term *term)
1024 {
1025 	memset(term, 0, sizeof(*term));
1026 	memset(state->termbitmap, 0, sizeof(state->termbitmap));
1027 	return __check_input_term(state, id, term);
1028 }
1029 
1030 /*
1031  * Feature Unit
1032  */
1033 
1034 /* feature unit control information */
1035 struct usb_feature_control_info {
1036 	int control;
1037 	const char *name;
1038 	int type;	/* data type for uac1 */
1039 	int type_uac2;	/* data type for uac2 if different from uac1, else -1 */
1040 };
1041 
1042 static const struct usb_feature_control_info audio_feature_info[] = {
1043 	{ UAC_FU_MUTE,			"Mute",			USB_MIXER_INV_BOOLEAN, -1 },
1044 	{ UAC_FU_VOLUME,		"Volume",		USB_MIXER_S16, -1 },
1045 	{ UAC_FU_BASS,			"Tone Control - Bass",	USB_MIXER_S8, -1 },
1046 	{ UAC_FU_MID,			"Tone Control - Mid",	USB_MIXER_S8, -1 },
1047 	{ UAC_FU_TREBLE,		"Tone Control - Treble", USB_MIXER_S8, -1 },
1048 	{ UAC_FU_GRAPHIC_EQUALIZER,	"Graphic Equalizer",	USB_MIXER_S8, -1 }, /* FIXME: not implemented yet */
1049 	{ UAC_FU_AUTOMATIC_GAIN,	"Auto Gain Control",	USB_MIXER_BOOLEAN, -1 },
1050 	{ UAC_FU_DELAY,			"Delay Control",	USB_MIXER_U16, USB_MIXER_U32 },
1051 	{ UAC_FU_BASS_BOOST,		"Bass Boost",		USB_MIXER_BOOLEAN, -1 },
1052 	{ UAC_FU_LOUDNESS,		"Loudness",		USB_MIXER_BOOLEAN, -1 },
1053 	/* UAC2 specific */
1054 	{ UAC2_FU_INPUT_GAIN,		"Input Gain Control",	USB_MIXER_S16, -1 },
1055 	{ UAC2_FU_INPUT_GAIN_PAD,	"Input Gain Pad Control", USB_MIXER_S16, -1 },
1056 	{ UAC2_FU_PHASE_INVERTER,	 "Phase Inverter Control", USB_MIXER_BOOLEAN, -1 },
1057 };
1058 
1059 static void usb_mixer_elem_info_free(struct usb_mixer_elem_info *cval)
1060 {
1061 	kfree(cval);
1062 }
1063 
1064 /* private_free callback */
1065 void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
1066 {
1067 	usb_mixer_elem_info_free(kctl->private_data);
1068 	kctl->private_data = NULL;
1069 }
1070 
1071 /*
1072  * interface to ALSA control for feature/mixer units
1073  */
1074 
1075 /* volume control quirks */
1076 static void volume_control_quirks(struct usb_mixer_elem_info *cval,
1077 				  struct snd_kcontrol *kctl)
1078 {
1079 	struct snd_usb_audio *chip = cval->head.mixer->chip;
1080 	switch (chip->usb_id) {
1081 	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
1082 	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
1083 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
1084 			cval->min = 0x0000;
1085 			cval->max = 0xffff;
1086 			cval->res = 0x00e6;
1087 			break;
1088 		}
1089 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1090 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1091 			cval->min = 0x00;
1092 			cval->max = 0xff;
1093 			break;
1094 		}
1095 		if (strstr(kctl->id.name, "Effect Return") != NULL) {
1096 			cval->min = 0xb706;
1097 			cval->max = 0xff7b;
1098 			cval->res = 0x0073;
1099 			break;
1100 		}
1101 		if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
1102 			(strstr(kctl->id.name, "Effect Send") != NULL)) {
1103 			cval->min = 0xb5fb; /* -73 dB = 0xb6ff */
1104 			cval->max = 0xfcfe;
1105 			cval->res = 0x0073;
1106 		}
1107 		break;
1108 
1109 	case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */
1110 	case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
1111 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
1112 			usb_audio_info(chip,
1113 				       "set quirk for FTU Effect Duration\n");
1114 			cval->min = 0x0000;
1115 			cval->max = 0x7f00;
1116 			cval->res = 0x0100;
1117 			break;
1118 		}
1119 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1120 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1121 			usb_audio_info(chip,
1122 				       "set quirks for FTU Effect Feedback/Volume\n");
1123 			cval->min = 0x00;
1124 			cval->max = 0x7f;
1125 			break;
1126 		}
1127 		break;
1128 
1129 	case USB_ID(0x0d8c, 0x0103):
1130 		if (!strcmp(kctl->id.name, "PCM Playback Volume")) {
1131 			usb_audio_info(chip,
1132 				 "set volume quirk for CM102-A+/102S+\n");
1133 			cval->min = -256;
1134 		}
1135 		break;
1136 
1137 	case USB_ID(0x0471, 0x0101):
1138 	case USB_ID(0x0471, 0x0104):
1139 	case USB_ID(0x0471, 0x0105):
1140 	case USB_ID(0x0672, 0x1041):
1141 	/* quirk for UDA1321/N101.
1142 	 * note that detection between firmware 2.1.1.7 (N101)
1143 	 * and later 2.1.1.21 is not very clear from datasheets.
1144 	 * I hope that the min value is -15360 for newer firmware --jk
1145 	 */
1146 		if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
1147 		    cval->min == -15616) {
1148 			usb_audio_info(chip,
1149 				 "set volume quirk for UDA1321/N101 chip\n");
1150 			cval->max = -256;
1151 		}
1152 		break;
1153 
1154 	case USB_ID(0x046d, 0x09a4):
1155 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1156 			usb_audio_info(chip,
1157 				"set volume quirk for QuickCam E3500\n");
1158 			cval->min = 6080;
1159 			cval->max = 8768;
1160 			cval->res = 192;
1161 		}
1162 		break;
1163 
1164 	case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
1165 	case USB_ID(0x046d, 0x0808):
1166 	case USB_ID(0x046d, 0x0809):
1167 	case USB_ID(0x046d, 0x0819): /* Logitech Webcam C210 */
1168 	case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
1169 	case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
1170 	case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
1171 	case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
1172 	case USB_ID(0x046d, 0x08ca): /* Logitech Quickcam Fusion */
1173 	case USB_ID(0x046d, 0x0991):
1174 	case USB_ID(0x046d, 0x09a2): /* QuickCam Communicate Deluxe/S7500 */
1175 	/* Most audio usb devices lie about volume resolution.
1176 	 * Most Logitech webcams have res = 384.
1177 	 * Probably there is some logitech magic behind this number --fishor
1178 	 */
1179 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1180 			usb_audio_info(chip,
1181 				"set resolution quirk: cval->res = 384\n");
1182 			cval->res = 384;
1183 		}
1184 		break;
1185 	}
1186 }
1187 
1188 /*
1189  * retrieve the minimum and maximum values for the specified control
1190  */
1191 static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
1192 				   int default_min, struct snd_kcontrol *kctl)
1193 {
1194 	/* for failsafe */
1195 	cval->min = default_min;
1196 	cval->max = cval->min + 1;
1197 	cval->res = 1;
1198 	cval->dBmin = cval->dBmax = 0;
1199 
1200 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1201 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1202 		cval->initialized = 1;
1203 	} else {
1204 		int minchn = 0;
1205 		if (cval->cmask) {
1206 			int i;
1207 			for (i = 0; i < MAX_CHANNELS; i++)
1208 				if (cval->cmask & (1 << i)) {
1209 					minchn = i + 1;
1210 					break;
1211 				}
1212 		}
1213 		if (get_ctl_value(cval, UAC_GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
1214 		    get_ctl_value(cval, UAC_GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
1215 			usb_audio_err(cval->head.mixer->chip,
1216 				      "%d:%d: cannot get min/max values for control %d (id %d)\n",
1217 				   cval->head.id, mixer_ctrl_intf(cval->head.mixer),
1218 							       cval->control, cval->head.id);
1219 			return -EINVAL;
1220 		}
1221 		if (get_ctl_value(cval, UAC_GET_RES,
1222 				  (cval->control << 8) | minchn,
1223 				  &cval->res) < 0) {
1224 			cval->res = 1;
1225 		} else {
1226 			int last_valid_res = cval->res;
1227 
1228 			while (cval->res > 1) {
1229 				if (snd_usb_mixer_set_ctl_value(cval, UAC_SET_RES,
1230 								(cval->control << 8) | minchn,
1231 								cval->res / 2) < 0)
1232 					break;
1233 				cval->res /= 2;
1234 			}
1235 			if (get_ctl_value(cval, UAC_GET_RES,
1236 					  (cval->control << 8) | minchn, &cval->res) < 0)
1237 				cval->res = last_valid_res;
1238 		}
1239 		if (cval->res == 0)
1240 			cval->res = 1;
1241 
1242 		/* Additional checks for the proper resolution
1243 		 *
1244 		 * Some devices report smaller resolutions than actually
1245 		 * reacting.  They don't return errors but simply clip
1246 		 * to the lower aligned value.
1247 		 */
1248 		if (cval->min + cval->res < cval->max) {
1249 			int last_valid_res = cval->res;
1250 			int saved, test, check;
1251 			if (get_cur_mix_raw(cval, minchn, &saved) < 0)
1252 				goto no_res_check;
1253 			for (;;) {
1254 				test = saved;
1255 				if (test < cval->max)
1256 					test += cval->res;
1257 				else
1258 					test -= cval->res;
1259 				if (test < cval->min || test > cval->max ||
1260 				    snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||
1261 				    get_cur_mix_raw(cval, minchn, &check)) {
1262 					cval->res = last_valid_res;
1263 					break;
1264 				}
1265 				if (test == check)
1266 					break;
1267 				cval->res *= 2;
1268 			}
1269 			snd_usb_set_cur_mix_value(cval, minchn, 0, saved);
1270 		}
1271 
1272 no_res_check:
1273 		cval->initialized = 1;
1274 	}
1275 
1276 	if (kctl)
1277 		volume_control_quirks(cval, kctl);
1278 
1279 	/* USB descriptions contain the dB scale in 1/256 dB unit
1280 	 * while ALSA TLV contains in 1/100 dB unit
1281 	 */
1282 	cval->dBmin = (convert_signed_value(cval, cval->min) * 100) / 256;
1283 	cval->dBmax = (convert_signed_value(cval, cval->max) * 100) / 256;
1284 	if (cval->dBmin > cval->dBmax) {
1285 		/* something is wrong; assume it's either from/to 0dB */
1286 		if (cval->dBmin < 0)
1287 			cval->dBmax = 0;
1288 		else if (cval->dBmin > 0)
1289 			cval->dBmin = 0;
1290 		if (cval->dBmin > cval->dBmax) {
1291 			/* totally crap, return an error */
1292 			return -EINVAL;
1293 		}
1294 	}
1295 
1296 	return 0;
1297 }
1298 
1299 #define get_min_max(cval, def)	get_min_max_with_quirks(cval, def, NULL)
1300 
1301 /* get a feature/mixer unit info */
1302 static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol,
1303 				  struct snd_ctl_elem_info *uinfo)
1304 {
1305 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1306 
1307 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1308 	    cval->val_type == USB_MIXER_INV_BOOLEAN)
1309 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1310 	else
1311 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1312 	uinfo->count = cval->channels;
1313 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1314 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1315 		uinfo->value.integer.min = 0;
1316 		uinfo->value.integer.max = 1;
1317 	} else {
1318 		if (!cval->initialized) {
1319 			get_min_max_with_quirks(cval, 0, kcontrol);
1320 			if (cval->initialized && cval->dBmin >= cval->dBmax) {
1321 				kcontrol->vd[0].access &=
1322 					~(SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1323 					  SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
1324 				snd_ctl_notify(cval->head.mixer->chip->card,
1325 					       SNDRV_CTL_EVENT_MASK_INFO,
1326 					       &kcontrol->id);
1327 			}
1328 		}
1329 		uinfo->value.integer.min = 0;
1330 		uinfo->value.integer.max =
1331 			(cval->max - cval->min + cval->res - 1) / cval->res;
1332 	}
1333 	return 0;
1334 }
1335 
1336 /* get the current value from feature/mixer unit */
1337 static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol,
1338 				 struct snd_ctl_elem_value *ucontrol)
1339 {
1340 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1341 	int c, cnt, val, err;
1342 
1343 	ucontrol->value.integer.value[0] = cval->min;
1344 	if (cval->cmask) {
1345 		cnt = 0;
1346 		for (c = 0; c < MAX_CHANNELS; c++) {
1347 			if (!(cval->cmask & (1 << c)))
1348 				continue;
1349 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &val);
1350 			if (err < 0)
1351 				return filter_error(cval, err);
1352 			val = get_relative_value(cval, val);
1353 			ucontrol->value.integer.value[cnt] = val;
1354 			cnt++;
1355 		}
1356 		return 0;
1357 	} else {
1358 		/* master channel */
1359 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1360 		if (err < 0)
1361 			return filter_error(cval, err);
1362 		val = get_relative_value(cval, val);
1363 		ucontrol->value.integer.value[0] = val;
1364 	}
1365 	return 0;
1366 }
1367 
1368 /* put the current value to feature/mixer unit */
1369 static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol,
1370 				 struct snd_ctl_elem_value *ucontrol)
1371 {
1372 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1373 	int c, cnt, val, oval, err;
1374 	int changed = 0;
1375 
1376 	if (cval->cmask) {
1377 		cnt = 0;
1378 		for (c = 0; c < MAX_CHANNELS; c++) {
1379 			if (!(cval->cmask & (1 << c)))
1380 				continue;
1381 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &oval);
1382 			if (err < 0)
1383 				return filter_error(cval, err);
1384 			val = ucontrol->value.integer.value[cnt];
1385 			val = get_abs_value(cval, val);
1386 			if (oval != val) {
1387 				snd_usb_set_cur_mix_value(cval, c + 1, cnt, val);
1388 				changed = 1;
1389 			}
1390 			cnt++;
1391 		}
1392 	} else {
1393 		/* master channel */
1394 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &oval);
1395 		if (err < 0)
1396 			return filter_error(cval, err);
1397 		val = ucontrol->value.integer.value[0];
1398 		val = get_abs_value(cval, val);
1399 		if (val != oval) {
1400 			snd_usb_set_cur_mix_value(cval, 0, 0, val);
1401 			changed = 1;
1402 		}
1403 	}
1404 	return changed;
1405 }
1406 
1407 /* get the boolean value from the master channel of a UAC control */
1408 static int mixer_ctl_master_bool_get(struct snd_kcontrol *kcontrol,
1409 				     struct snd_ctl_elem_value *ucontrol)
1410 {
1411 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1412 	int val, err;
1413 
1414 	err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1415 	if (err < 0)
1416 		return filter_error(cval, err);
1417 	val = (val != 0);
1418 	ucontrol->value.integer.value[0] = val;
1419 	return 0;
1420 }
1421 
1422 /* get the connectors status and report it as boolean type */
1423 static int mixer_ctl_connector_get(struct snd_kcontrol *kcontrol,
1424 				   struct snd_ctl_elem_value *ucontrol)
1425 {
1426 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1427 	struct snd_usb_audio *chip = cval->head.mixer->chip;
1428 	int idx = 0, validx, ret, val;
1429 
1430 	validx = cval->control << 8 | 0;
1431 
1432 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
1433 	if (ret)
1434 		goto error;
1435 
1436 	idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
1437 	if (cval->head.mixer->protocol == UAC_VERSION_2) {
1438 		struct uac2_connectors_ctl_blk uac2_conn;
1439 
1440 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1441 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1442 				      validx, idx, &uac2_conn, sizeof(uac2_conn));
1443 		val = !!uac2_conn.bNrChannels;
1444 	} else { /* UAC_VERSION_3 */
1445 		struct uac3_insertion_ctl_blk uac3_conn;
1446 
1447 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1448 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1449 				      validx, idx, &uac3_conn, sizeof(uac3_conn));
1450 		val = !!uac3_conn.bmConInserted;
1451 	}
1452 
1453 	snd_usb_unlock_shutdown(chip);
1454 
1455 	if (ret < 0) {
1456 error:
1457 		usb_audio_err(chip,
1458 			"cannot get connectors status: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
1459 			UAC_GET_CUR, validx, idx, cval->val_type);
1460 		return filter_error(cval, ret);
1461 	}
1462 
1463 	ucontrol->value.integer.value[0] = val;
1464 	return 0;
1465 }
1466 
1467 static const struct snd_kcontrol_new usb_feature_unit_ctl = {
1468 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1469 	.name = "", /* will be filled later manually */
1470 	.info = mixer_ctl_feature_info,
1471 	.get = mixer_ctl_feature_get,
1472 	.put = mixer_ctl_feature_put,
1473 };
1474 
1475 /* the read-only variant */
1476 static const struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
1477 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1478 	.name = "", /* will be filled later manually */
1479 	.info = mixer_ctl_feature_info,
1480 	.get = mixer_ctl_feature_get,
1481 	.put = NULL,
1482 };
1483 
1484 /*
1485  * A control which shows the boolean value from reading a UAC control on
1486  * the master channel.
1487  */
1488 static const struct snd_kcontrol_new usb_bool_master_control_ctl_ro = {
1489 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1490 	.name = "", /* will be filled later manually */
1491 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1492 	.info = snd_ctl_boolean_mono_info,
1493 	.get = mixer_ctl_master_bool_get,
1494 	.put = NULL,
1495 };
1496 
1497 static const struct snd_kcontrol_new usb_connector_ctl_ro = {
1498 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1499 	.name = "", /* will be filled later manually */
1500 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1501 	.info = snd_ctl_boolean_mono_info,
1502 	.get = mixer_ctl_connector_get,
1503 	.put = NULL,
1504 };
1505 
1506 /*
1507  * This symbol is exported in order to allow the mixer quirks to
1508  * hook up to the standard feature unit control mechanism
1509  */
1510 const struct snd_kcontrol_new *snd_usb_feature_unit_ctl = &usb_feature_unit_ctl;
1511 
1512 /*
1513  * build a feature control
1514  */
1515 static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
1516 {
1517 	return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
1518 }
1519 
1520 /*
1521  * A lot of headsets/headphones have a "Speaker" mixer. Make sure we
1522  * rename it to "Headphone". We determine if something is a headphone
1523  * similar to how udev determines form factor.
1524  */
1525 static void check_no_speaker_on_headset(struct snd_kcontrol *kctl,
1526 					struct snd_card *card)
1527 {
1528 	const char *names_to_check[] = {
1529 		"Headset", "headset", "Headphone", "headphone", NULL};
1530 	const char **s;
1531 	bool found = false;
1532 
1533 	if (strcmp("Speaker", kctl->id.name))
1534 		return;
1535 
1536 	for (s = names_to_check; *s; s++)
1537 		if (strstr(card->shortname, *s)) {
1538 			found = true;
1539 			break;
1540 		}
1541 
1542 	if (!found)
1543 		return;
1544 
1545 	strlcpy(kctl->id.name, "Headphone", sizeof(kctl->id.name));
1546 }
1547 
1548 static const struct usb_feature_control_info *get_feature_control_info(int control)
1549 {
1550 	int i;
1551 
1552 	for (i = 0; i < ARRAY_SIZE(audio_feature_info); ++i) {
1553 		if (audio_feature_info[i].control == control)
1554 			return &audio_feature_info[i];
1555 	}
1556 	return NULL;
1557 }
1558 
1559 static void __build_feature_ctl(struct usb_mixer_interface *mixer,
1560 				const struct usbmix_name_map *imap,
1561 				unsigned int ctl_mask, int control,
1562 				struct usb_audio_term *iterm,
1563 				struct usb_audio_term *oterm,
1564 				int unitid, int nameid, int readonly_mask)
1565 {
1566 	const struct usb_feature_control_info *ctl_info;
1567 	unsigned int len = 0;
1568 	int mapped_name = 0;
1569 	struct snd_kcontrol *kctl;
1570 	struct usb_mixer_elem_info *cval;
1571 	const struct usbmix_name_map *map;
1572 	unsigned int range;
1573 
1574 	if (control == UAC_FU_GRAPHIC_EQUALIZER) {
1575 		/* FIXME: not supported yet */
1576 		return;
1577 	}
1578 
1579 	map = find_map(imap, unitid, control);
1580 	if (check_ignored_ctl(map))
1581 		return;
1582 
1583 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1584 	if (!cval)
1585 		return;
1586 	snd_usb_mixer_elem_init_std(&cval->head, mixer, unitid);
1587 	cval->control = control;
1588 	cval->cmask = ctl_mask;
1589 
1590 	ctl_info = get_feature_control_info(control);
1591 	if (!ctl_info) {
1592 		usb_mixer_elem_info_free(cval);
1593 		return;
1594 	}
1595 	if (mixer->protocol == UAC_VERSION_1)
1596 		cval->val_type = ctl_info->type;
1597 	else /* UAC_VERSION_2 */
1598 		cval->val_type = ctl_info->type_uac2 >= 0 ?
1599 			ctl_info->type_uac2 : ctl_info->type;
1600 
1601 	if (ctl_mask == 0) {
1602 		cval->channels = 1;	/* master channel */
1603 		cval->master_readonly = readonly_mask;
1604 	} else {
1605 		int i, c = 0;
1606 		for (i = 0; i < 16; i++)
1607 			if (ctl_mask & (1 << i))
1608 				c++;
1609 		cval->channels = c;
1610 		cval->ch_readonly = readonly_mask;
1611 	}
1612 
1613 	/*
1614 	 * If all channels in the mask are marked read-only, make the control
1615 	 * read-only. snd_usb_set_cur_mix_value() will check the mask again and won't
1616 	 * issue write commands to read-only channels.
1617 	 */
1618 	if (cval->channels == readonly_mask)
1619 		kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
1620 	else
1621 		kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1622 
1623 	if (!kctl) {
1624 		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
1625 		usb_mixer_elem_info_free(cval);
1626 		return;
1627 	}
1628 	kctl->private_free = snd_usb_mixer_elem_free;
1629 
1630 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1631 	mapped_name = len != 0;
1632 	if (!len && nameid)
1633 		len = snd_usb_copy_string_desc(mixer->chip, nameid,
1634 				kctl->id.name, sizeof(kctl->id.name));
1635 
1636 	switch (control) {
1637 	case UAC_FU_MUTE:
1638 	case UAC_FU_VOLUME:
1639 		/*
1640 		 * determine the control name.  the rule is:
1641 		 * - if a name id is given in descriptor, use it.
1642 		 * - if the connected input can be determined, then use the name
1643 		 *   of terminal type.
1644 		 * - if the connected output can be determined, use it.
1645 		 * - otherwise, anonymous name.
1646 		 */
1647 		if (!len) {
1648 			if (iterm)
1649 				len = get_term_name(mixer->chip, iterm,
1650 						    kctl->id.name,
1651 						    sizeof(kctl->id.name), 1);
1652 			if (!len && oterm)
1653 				len = get_term_name(mixer->chip, oterm,
1654 						    kctl->id.name,
1655 						    sizeof(kctl->id.name), 1);
1656 			if (!len)
1657 				snprintf(kctl->id.name, sizeof(kctl->id.name),
1658 					 "Feature %d", unitid);
1659 		}
1660 
1661 		if (!mapped_name)
1662 			check_no_speaker_on_headset(kctl, mixer->chip->card);
1663 
1664 		/*
1665 		 * determine the stream direction:
1666 		 * if the connected output is USB stream, then it's likely a
1667 		 * capture stream.  otherwise it should be playback (hopefully :)
1668 		 */
1669 		if (!mapped_name && oterm && !(oterm->type >> 16)) {
1670 			if ((oterm->type & 0xff00) == 0x0100)
1671 				append_ctl_name(kctl, " Capture");
1672 			else
1673 				append_ctl_name(kctl, " Playback");
1674 		}
1675 		append_ctl_name(kctl, control == UAC_FU_MUTE ?
1676 				" Switch" : " Volume");
1677 		break;
1678 	default:
1679 		if (!len)
1680 			strlcpy(kctl->id.name, audio_feature_info[control-1].name,
1681 				sizeof(kctl->id.name));
1682 		break;
1683 	}
1684 
1685 	/* get min/max values */
1686 	get_min_max_with_quirks(cval, 0, kctl);
1687 
1688 	/* skip a bogus volume range */
1689 	if (cval->max <= cval->min) {
1690 		usb_audio_dbg(mixer->chip,
1691 			      "[%d] FU [%s] skipped due to invalid volume\n",
1692 			      cval->head.id, kctl->id.name);
1693 		snd_ctl_free_one(kctl);
1694 		return;
1695 	}
1696 
1697 
1698 	if (control == UAC_FU_VOLUME) {
1699 		check_mapped_dB(map, cval);
1700 		if (cval->dBmin < cval->dBmax || !cval->initialized) {
1701 			kctl->tlv.c = snd_usb_mixer_vol_tlv;
1702 			kctl->vd[0].access |=
1703 				SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1704 				SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1705 		}
1706 	}
1707 
1708 	snd_usb_mixer_fu_apply_quirk(mixer, cval, unitid, kctl);
1709 
1710 	range = (cval->max - cval->min) / cval->res;
1711 	/*
1712 	 * Are there devices with volume range more than 255? I use a bit more
1713 	 * to be sure. 384 is a resolution magic number found on Logitech
1714 	 * devices. It will definitively catch all buggy Logitech devices.
1715 	 */
1716 	if (range > 384) {
1717 		usb_audio_warn(mixer->chip,
1718 			       "Warning! Unlikely big volume range (=%u), cval->res is probably wrong.",
1719 			       range);
1720 		usb_audio_warn(mixer->chip,
1721 			       "[%d] FU [%s] ch = %d, val = %d/%d/%d",
1722 			       cval->head.id, kctl->id.name, cval->channels,
1723 			       cval->min, cval->max, cval->res);
1724 	}
1725 
1726 	usb_audio_dbg(mixer->chip, "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
1727 		      cval->head.id, kctl->id.name, cval->channels,
1728 		      cval->min, cval->max, cval->res);
1729 	snd_usb_mixer_add_control(&cval->head, kctl);
1730 }
1731 
1732 static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
1733 			      unsigned int ctl_mask, int control,
1734 			      struct usb_audio_term *iterm, int unitid,
1735 			      int readonly_mask)
1736 {
1737 	struct uac_feature_unit_descriptor *desc = raw_desc;
1738 	int nameid = uac_feature_unit_iFeature(desc);
1739 
1740 	__build_feature_ctl(state->mixer, state->map, ctl_mask, control,
1741 			iterm, &state->oterm, unitid, nameid, readonly_mask);
1742 }
1743 
1744 static void build_feature_ctl_badd(struct usb_mixer_interface *mixer,
1745 			      unsigned int ctl_mask, int control, int unitid,
1746 			      const struct usbmix_name_map *badd_map)
1747 {
1748 	__build_feature_ctl(mixer, badd_map, ctl_mask, control,
1749 			NULL, NULL, unitid, 0, 0);
1750 }
1751 
1752 static void get_connector_control_name(struct usb_mixer_interface *mixer,
1753 				       struct usb_audio_term *term,
1754 				       bool is_input, char *name, int name_size)
1755 {
1756 	int name_len = get_term_name(mixer->chip, term, name, name_size, 0);
1757 
1758 	if (name_len == 0)
1759 		strlcpy(name, "Unknown", name_size);
1760 
1761 	/*
1762 	 *  sound/core/ctljack.c has a convention of naming jack controls
1763 	 * by ending in " Jack".  Make it slightly more useful by
1764 	 * indicating Input or Output after the terminal name.
1765 	 */
1766 	if (is_input)
1767 		strlcat(name, " - Input Jack", name_size);
1768 	else
1769 		strlcat(name, " - Output Jack", name_size);
1770 }
1771 
1772 /* Build a mixer control for a UAC connector control (jack-detect) */
1773 static void build_connector_control(struct usb_mixer_interface *mixer,
1774 				    const struct usbmix_name_map *imap,
1775 				    struct usb_audio_term *term, bool is_input)
1776 {
1777 	struct snd_kcontrol *kctl;
1778 	struct usb_mixer_elem_info *cval;
1779 
1780 	if (check_ignored_ctl(find_map(imap, term->id, 0)))
1781 		return;
1782 
1783 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1784 	if (!cval)
1785 		return;
1786 	snd_usb_mixer_elem_init_std(&cval->head, mixer, term->id);
1787 	/*
1788 	 * UAC2: The first byte from reading the UAC2_TE_CONNECTOR control returns the
1789 	 * number of channels connected.
1790 	 *
1791 	 * UAC3: The first byte specifies size of bitmap for the inserted controls. The
1792 	 * following byte(s) specifies which connectors are inserted.
1793 	 *
1794 	 * This boolean ctl will simply report if any channels are connected
1795 	 * or not.
1796 	 */
1797 	if (mixer->protocol == UAC_VERSION_2)
1798 		cval->control = UAC2_TE_CONNECTOR;
1799 	else /* UAC_VERSION_3 */
1800 		cval->control = UAC3_TE_INSERTION;
1801 
1802 	cval->val_type = USB_MIXER_BOOLEAN;
1803 	cval->channels = 1; /* report true if any channel is connected */
1804 	cval->min = 0;
1805 	cval->max = 1;
1806 	kctl = snd_ctl_new1(&usb_connector_ctl_ro, cval);
1807 	if (!kctl) {
1808 		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
1809 		usb_mixer_elem_info_free(cval);
1810 		return;
1811 	}
1812 	get_connector_control_name(mixer, term, is_input, kctl->id.name,
1813 				   sizeof(kctl->id.name));
1814 	kctl->private_free = snd_usb_mixer_elem_free;
1815 	snd_usb_mixer_add_control(&cval->head, kctl);
1816 }
1817 
1818 static int parse_clock_source_unit(struct mixer_build *state, int unitid,
1819 				   void *_ftr)
1820 {
1821 	struct uac_clock_source_descriptor *hdr = _ftr;
1822 	struct usb_mixer_elem_info *cval;
1823 	struct snd_kcontrol *kctl;
1824 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
1825 	int ret;
1826 
1827 	if (state->mixer->protocol != UAC_VERSION_2)
1828 		return -EINVAL;
1829 
1830 	/*
1831 	 * The only property of this unit we are interested in is the
1832 	 * clock source validity. If that isn't readable, just bail out.
1833 	 */
1834 	if (!uac_v2v3_control_is_readable(hdr->bmControls,
1835 				      UAC2_CS_CONTROL_CLOCK_VALID))
1836 		return 0;
1837 
1838 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1839 	if (!cval)
1840 		return -ENOMEM;
1841 
1842 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, hdr->bClockID);
1843 
1844 	cval->min = 0;
1845 	cval->max = 1;
1846 	cval->channels = 1;
1847 	cval->val_type = USB_MIXER_BOOLEAN;
1848 	cval->control = UAC2_CS_CONTROL_CLOCK_VALID;
1849 
1850 	cval->master_readonly = 1;
1851 	/* From UAC2 5.2.5.1.2 "Only the get request is supported." */
1852 	kctl = snd_ctl_new1(&usb_bool_master_control_ctl_ro, cval);
1853 
1854 	if (!kctl) {
1855 		usb_mixer_elem_info_free(cval);
1856 		return -ENOMEM;
1857 	}
1858 
1859 	kctl->private_free = snd_usb_mixer_elem_free;
1860 	ret = snd_usb_copy_string_desc(state->chip, hdr->iClockSource,
1861 				       name, sizeof(name));
1862 	if (ret > 0)
1863 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1864 			 "%s Validity", name);
1865 	else
1866 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1867 			 "Clock Source %d Validity", hdr->bClockID);
1868 
1869 	return snd_usb_mixer_add_control(&cval->head, kctl);
1870 }
1871 
1872 /*
1873  * parse a feature unit
1874  *
1875  * most of controls are defined here.
1876  */
1877 static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
1878 				    void *_ftr)
1879 {
1880 	int channels, i, j;
1881 	struct usb_audio_term iterm;
1882 	unsigned int master_bits;
1883 	int err, csize;
1884 	struct uac_feature_unit_descriptor *hdr = _ftr;
1885 	__u8 *bmaControls;
1886 
1887 	if (state->mixer->protocol == UAC_VERSION_1) {
1888 		csize = hdr->bControlSize;
1889 		channels = (hdr->bLength - 7) / csize - 1;
1890 		bmaControls = hdr->bmaControls;
1891 	} else if (state->mixer->protocol == UAC_VERSION_2) {
1892 		struct uac2_feature_unit_descriptor *ftr = _ftr;
1893 		csize = 4;
1894 		channels = (hdr->bLength - 6) / 4 - 1;
1895 		bmaControls = ftr->bmaControls;
1896 	} else { /* UAC_VERSION_3 */
1897 		struct uac3_feature_unit_descriptor *ftr = _ftr;
1898 
1899 		csize = 4;
1900 		channels = (ftr->bLength - 7) / 4 - 1;
1901 		bmaControls = ftr->bmaControls;
1902 	}
1903 
1904 	/* parse the source unit */
1905 	err = parse_audio_unit(state, hdr->bSourceID);
1906 	if (err < 0)
1907 		return err;
1908 
1909 	/* determine the input source type and name */
1910 	err = check_input_term(state, hdr->bSourceID, &iterm);
1911 	if (err < 0)
1912 		return err;
1913 
1914 	master_bits = snd_usb_combine_bytes(bmaControls, csize);
1915 	/* master configuration quirks */
1916 	switch (state->chip->usb_id) {
1917 	case USB_ID(0x08bb, 0x2702):
1918 		usb_audio_info(state->chip,
1919 			       "usbmixer: master volume quirk for PCM2702 chip\n");
1920 		/* disable non-functional volume control */
1921 		master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
1922 		break;
1923 	case USB_ID(0x1130, 0xf211):
1924 		usb_audio_info(state->chip,
1925 			       "usbmixer: volume control quirk for Tenx TP6911 Audio Headset\n");
1926 		/* disable non-functional volume control */
1927 		channels = 0;
1928 		break;
1929 
1930 	}
1931 
1932 	if (state->mixer->protocol == UAC_VERSION_1) {
1933 		/* check all control types */
1934 		for (i = 0; i < 10; i++) {
1935 			unsigned int ch_bits = 0;
1936 			int control = audio_feature_info[i].control;
1937 
1938 			for (j = 0; j < channels; j++) {
1939 				unsigned int mask;
1940 
1941 				mask = snd_usb_combine_bytes(bmaControls +
1942 							     csize * (j+1), csize);
1943 				if (mask & (1 << i))
1944 					ch_bits |= (1 << j);
1945 			}
1946 			/* audio class v1 controls are never read-only */
1947 
1948 			/*
1949 			 * The first channel must be set
1950 			 * (for ease of programming).
1951 			 */
1952 			if (ch_bits & 1)
1953 				build_feature_ctl(state, _ftr, ch_bits, control,
1954 						  &iterm, unitid, 0);
1955 			if (master_bits & (1 << i))
1956 				build_feature_ctl(state, _ftr, 0, control,
1957 						  &iterm, unitid, 0);
1958 		}
1959 	} else { /* UAC_VERSION_2/3 */
1960 		for (i = 0; i < ARRAY_SIZE(audio_feature_info); i++) {
1961 			unsigned int ch_bits = 0;
1962 			unsigned int ch_read_only = 0;
1963 			int control = audio_feature_info[i].control;
1964 
1965 			for (j = 0; j < channels; j++) {
1966 				unsigned int mask;
1967 
1968 				mask = snd_usb_combine_bytes(bmaControls +
1969 							     csize * (j+1), csize);
1970 				if (uac_v2v3_control_is_readable(mask, control)) {
1971 					ch_bits |= (1 << j);
1972 					if (!uac_v2v3_control_is_writeable(mask, control))
1973 						ch_read_only |= (1 << j);
1974 				}
1975 			}
1976 
1977 			/*
1978 			 * NOTE: build_feature_ctl() will mark the control
1979 			 * read-only if all channels are marked read-only in
1980 			 * the descriptors. Otherwise, the control will be
1981 			 * reported as writeable, but the driver will not
1982 			 * actually issue a write command for read-only
1983 			 * channels.
1984 			 */
1985 
1986 			/*
1987 			 * The first channel must be set
1988 			 * (for ease of programming).
1989 			 */
1990 			if (ch_bits & 1)
1991 				build_feature_ctl(state, _ftr, ch_bits, control,
1992 						  &iterm, unitid, ch_read_only);
1993 			if (uac_v2v3_control_is_readable(master_bits, control))
1994 				build_feature_ctl(state, _ftr, 0, control,
1995 						  &iterm, unitid,
1996 						  !uac_v2v3_control_is_writeable(master_bits,
1997 										 control));
1998 		}
1999 	}
2000 
2001 	return 0;
2002 }
2003 
2004 /*
2005  * Mixer Unit
2006  */
2007 
2008 /* check whether the given in/out overflows bmMixerControls matrix */
2009 static bool mixer_bitmap_overflow(struct uac_mixer_unit_descriptor *desc,
2010 				  int protocol, int num_ins, int num_outs)
2011 {
2012 	u8 *hdr = (u8 *)desc;
2013 	u8 *c = uac_mixer_unit_bmControls(desc, protocol);
2014 	size_t rest; /* remaining bytes after bmMixerControls */
2015 
2016 	switch (protocol) {
2017 	case UAC_VERSION_1:
2018 	default:
2019 		rest = 1; /* iMixer */
2020 		break;
2021 	case UAC_VERSION_2:
2022 		rest = 2; /* bmControls + iMixer */
2023 		break;
2024 	case UAC_VERSION_3:
2025 		rest = 6; /* bmControls + wMixerDescrStr */
2026 		break;
2027 	}
2028 
2029 	/* overflow? */
2030 	return c + (num_ins * num_outs + 7) / 8 + rest > hdr + hdr[0];
2031 }
2032 
2033 /*
2034  * build a mixer unit control
2035  *
2036  * the callbacks are identical with feature unit.
2037  * input channel number (zero based) is given in control field instead.
2038  */
2039 static void build_mixer_unit_ctl(struct mixer_build *state,
2040 				 struct uac_mixer_unit_descriptor *desc,
2041 				 int in_pin, int in_ch, int num_outs,
2042 				 int unitid, struct usb_audio_term *iterm)
2043 {
2044 	struct usb_mixer_elem_info *cval;
2045 	unsigned int i, len;
2046 	struct snd_kcontrol *kctl;
2047 	const struct usbmix_name_map *map;
2048 
2049 	map = find_map(state->map, unitid, 0);
2050 	if (check_ignored_ctl(map))
2051 		return;
2052 
2053 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2054 	if (!cval)
2055 		return;
2056 
2057 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2058 	cval->control = in_ch + 1; /* based on 1 */
2059 	cval->val_type = USB_MIXER_S16;
2060 	for (i = 0; i < num_outs; i++) {
2061 		__u8 *c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
2062 
2063 		if (check_matrix_bitmap(c, in_ch, i, num_outs)) {
2064 			cval->cmask |= (1 << i);
2065 			cval->channels++;
2066 		}
2067 	}
2068 
2069 	/* get min/max values */
2070 	get_min_max(cval, 0);
2071 
2072 	kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
2073 	if (!kctl) {
2074 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2075 		usb_mixer_elem_info_free(cval);
2076 		return;
2077 	}
2078 	kctl->private_free = snd_usb_mixer_elem_free;
2079 
2080 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2081 	if (!len)
2082 		len = get_term_name(state->chip, iterm, kctl->id.name,
2083 				    sizeof(kctl->id.name), 0);
2084 	if (!len)
2085 		len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
2086 	append_ctl_name(kctl, " Volume");
2087 
2088 	usb_audio_dbg(state->chip, "[%d] MU [%s] ch = %d, val = %d/%d\n",
2089 		    cval->head.id, kctl->id.name, cval->channels, cval->min, cval->max);
2090 	snd_usb_mixer_add_control(&cval->head, kctl);
2091 }
2092 
2093 static int parse_audio_input_terminal(struct mixer_build *state, int unitid,
2094 				      void *raw_desc)
2095 {
2096 	struct usb_audio_term iterm;
2097 	unsigned int control, bmctls, term_id;
2098 
2099 	if (state->mixer->protocol == UAC_VERSION_2) {
2100 		struct uac2_input_terminal_descriptor *d_v2 = raw_desc;
2101 		control = UAC2_TE_CONNECTOR;
2102 		term_id = d_v2->bTerminalID;
2103 		bmctls = le16_to_cpu(d_v2->bmControls);
2104 	} else if (state->mixer->protocol == UAC_VERSION_3) {
2105 		struct uac3_input_terminal_descriptor *d_v3 = raw_desc;
2106 		control = UAC3_TE_INSERTION;
2107 		term_id = d_v3->bTerminalID;
2108 		bmctls = le32_to_cpu(d_v3->bmControls);
2109 	} else {
2110 		return 0; /* UAC1. No Insertion control */
2111 	}
2112 
2113 	check_input_term(state, term_id, &iterm);
2114 
2115 	/* Check for jack detection. */
2116 	if ((iterm.type & 0xff00) != 0x0100 &&
2117 	    uac_v2v3_control_is_readable(bmctls, control))
2118 		build_connector_control(state->mixer, state->map, &iterm, true);
2119 
2120 	return 0;
2121 }
2122 
2123 /*
2124  * parse a mixer unit
2125  */
2126 static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
2127 				  void *raw_desc)
2128 {
2129 	struct uac_mixer_unit_descriptor *desc = raw_desc;
2130 	struct usb_audio_term iterm;
2131 	int input_pins, num_ins, num_outs;
2132 	int pin, ich, err;
2133 
2134 	err = uac_mixer_unit_get_channels(state, desc);
2135 	if (err < 0) {
2136 		usb_audio_err(state->chip,
2137 			      "invalid MIXER UNIT descriptor %d\n",
2138 			      unitid);
2139 		return err;
2140 	}
2141 
2142 	num_outs = err;
2143 	input_pins = desc->bNrInPins;
2144 
2145 	num_ins = 0;
2146 	ich = 0;
2147 	for (pin = 0; pin < input_pins; pin++) {
2148 		err = parse_audio_unit(state, desc->baSourceID[pin]);
2149 		if (err < 0)
2150 			continue;
2151 		/* no bmControls field (e.g. Maya44) -> ignore */
2152 		if (!num_outs)
2153 			continue;
2154 		err = check_input_term(state, desc->baSourceID[pin], &iterm);
2155 		if (err < 0)
2156 			return err;
2157 		num_ins += iterm.channels;
2158 		if (mixer_bitmap_overflow(desc, state->mixer->protocol,
2159 					  num_ins, num_outs))
2160 			break;
2161 		for (; ich < num_ins; ich++) {
2162 			int och, ich_has_controls = 0;
2163 
2164 			for (och = 0; och < num_outs; och++) {
2165 				__u8 *c = uac_mixer_unit_bmControls(desc,
2166 						state->mixer->protocol);
2167 
2168 				if (check_matrix_bitmap(c, ich, och, num_outs)) {
2169 					ich_has_controls = 1;
2170 					break;
2171 				}
2172 			}
2173 			if (ich_has_controls)
2174 				build_mixer_unit_ctl(state, desc, pin, ich, num_outs,
2175 						     unitid, &iterm);
2176 		}
2177 	}
2178 	return 0;
2179 }
2180 
2181 /*
2182  * Processing Unit / Extension Unit
2183  */
2184 
2185 /* get callback for processing/extension unit */
2186 static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol,
2187 				  struct snd_ctl_elem_value *ucontrol)
2188 {
2189 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2190 	int err, val;
2191 
2192 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2193 	if (err < 0) {
2194 		ucontrol->value.integer.value[0] = cval->min;
2195 		return filter_error(cval, err);
2196 	}
2197 	val = get_relative_value(cval, val);
2198 	ucontrol->value.integer.value[0] = val;
2199 	return 0;
2200 }
2201 
2202 /* put callback for processing/extension unit */
2203 static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol,
2204 				  struct snd_ctl_elem_value *ucontrol)
2205 {
2206 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2207 	int val, oval, err;
2208 
2209 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2210 	if (err < 0)
2211 		return filter_error(cval, err);
2212 	val = ucontrol->value.integer.value[0];
2213 	val = get_abs_value(cval, val);
2214 	if (val != oval) {
2215 		set_cur_ctl_value(cval, cval->control << 8, val);
2216 		return 1;
2217 	}
2218 	return 0;
2219 }
2220 
2221 /* alsa control interface for processing/extension unit */
2222 static const struct snd_kcontrol_new mixer_procunit_ctl = {
2223 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2224 	.name = "", /* will be filled later */
2225 	.info = mixer_ctl_feature_info,
2226 	.get = mixer_ctl_procunit_get,
2227 	.put = mixer_ctl_procunit_put,
2228 };
2229 
2230 /*
2231  * predefined data for processing units
2232  */
2233 struct procunit_value_info {
2234 	int control;
2235 	const char *suffix;
2236 	int val_type;
2237 	int min_value;
2238 };
2239 
2240 struct procunit_info {
2241 	int type;
2242 	char *name;
2243 	const struct procunit_value_info *values;
2244 };
2245 
2246 static const struct procunit_value_info undefined_proc_info[] = {
2247 	{ 0x00, "Control Undefined", 0 },
2248 	{ 0 }
2249 };
2250 
2251 static const struct procunit_value_info updown_proc_info[] = {
2252 	{ UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2253 	{ UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2254 	{ 0 }
2255 };
2256 static const struct procunit_value_info prologic_proc_info[] = {
2257 	{ UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2258 	{ UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2259 	{ 0 }
2260 };
2261 static const struct procunit_value_info threed_enh_proc_info[] = {
2262 	{ UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2263 	{ UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
2264 	{ 0 }
2265 };
2266 static const struct procunit_value_info reverb_proc_info[] = {
2267 	{ UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2268 	{ UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
2269 	{ UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
2270 	{ UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
2271 	{ 0 }
2272 };
2273 static const struct procunit_value_info chorus_proc_info[] = {
2274 	{ UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2275 	{ UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
2276 	{ UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
2277 	{ UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
2278 	{ 0 }
2279 };
2280 static const struct procunit_value_info dcr_proc_info[] = {
2281 	{ UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2282 	{ UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
2283 	{ UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
2284 	{ UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
2285 	{ UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
2286 	{ UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
2287 	{ 0 }
2288 };
2289 
2290 static const struct procunit_info procunits[] = {
2291 	{ UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
2292 	{ UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
2293 	{ UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
2294 	{ UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
2295 	{ UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
2296 	{ UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
2297 	{ 0 },
2298 };
2299 
2300 static const struct procunit_value_info uac3_updown_proc_info[] = {
2301 	{ UAC3_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2302 	{ 0 }
2303 };
2304 static const struct procunit_value_info uac3_stereo_ext_proc_info[] = {
2305 	{ UAC3_EXT_WIDTH_CONTROL, "Width Control", USB_MIXER_U8 },
2306 	{ 0 }
2307 };
2308 
2309 static const struct procunit_info uac3_procunits[] = {
2310 	{ UAC3_PROCESS_UP_DOWNMIX, "Up Down", uac3_updown_proc_info },
2311 	{ UAC3_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", uac3_stereo_ext_proc_info },
2312 	{ UAC3_PROCESS_MULTI_FUNCTION, "Multi-Function", undefined_proc_info },
2313 	{ 0 },
2314 };
2315 
2316 /*
2317  * predefined data for extension units
2318  */
2319 static const struct procunit_value_info clock_rate_xu_info[] = {
2320 	{ USB_XU_CLOCK_RATE_SELECTOR, "Selector", USB_MIXER_U8, 0 },
2321 	{ 0 }
2322 };
2323 static const struct procunit_value_info clock_source_xu_info[] = {
2324 	{ USB_XU_CLOCK_SOURCE_SELECTOR, "External", USB_MIXER_BOOLEAN },
2325 	{ 0 }
2326 };
2327 static const struct procunit_value_info spdif_format_xu_info[] = {
2328 	{ USB_XU_DIGITAL_FORMAT_SELECTOR, "SPDIF/AC3", USB_MIXER_BOOLEAN },
2329 	{ 0 }
2330 };
2331 static const struct procunit_value_info soft_limit_xu_info[] = {
2332 	{ USB_XU_SOFT_LIMIT_SELECTOR, " ", USB_MIXER_BOOLEAN },
2333 	{ 0 }
2334 };
2335 static const struct procunit_info extunits[] = {
2336 	{ USB_XU_CLOCK_RATE, "Clock rate", clock_rate_xu_info },
2337 	{ USB_XU_CLOCK_SOURCE, "DigitalIn CLK source", clock_source_xu_info },
2338 	{ USB_XU_DIGITAL_IO_STATUS, "DigitalOut format:", spdif_format_xu_info },
2339 	{ USB_XU_DEVICE_OPTIONS, "AnalogueIn Soft Limit", soft_limit_xu_info },
2340 	{ 0 }
2341 };
2342 
2343 /*
2344  * build a processing/extension unit
2345  */
2346 static int build_audio_procunit(struct mixer_build *state, int unitid,
2347 				void *raw_desc, const struct procunit_info *list,
2348 				bool extension_unit)
2349 {
2350 	struct uac_processing_unit_descriptor *desc = raw_desc;
2351 	int num_ins;
2352 	struct usb_mixer_elem_info *cval;
2353 	struct snd_kcontrol *kctl;
2354 	int i, err, nameid, type, len;
2355 	const struct procunit_info *info;
2356 	const struct procunit_value_info *valinfo;
2357 	const struct usbmix_name_map *map;
2358 	static const struct procunit_value_info default_value_info[] = {
2359 		{ 0x01, "Switch", USB_MIXER_BOOLEAN },
2360 		{ 0 }
2361 	};
2362 	static const struct procunit_info default_info = {
2363 		0, NULL, default_value_info
2364 	};
2365 	const char *name = extension_unit ?
2366 		"Extension Unit" : "Processing Unit";
2367 
2368 	num_ins = desc->bNrInPins;
2369 	for (i = 0; i < num_ins; i++) {
2370 		err = parse_audio_unit(state, desc->baSourceID[i]);
2371 		if (err < 0)
2372 			return err;
2373 	}
2374 
2375 	type = le16_to_cpu(desc->wProcessType);
2376 	for (info = list; info && info->type; info++)
2377 		if (info->type == type)
2378 			break;
2379 	if (!info || !info->type)
2380 		info = &default_info;
2381 
2382 	for (valinfo = info->values; valinfo->control; valinfo++) {
2383 		__u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);
2384 
2385 		if (state->mixer->protocol == UAC_VERSION_1) {
2386 			if (!(controls[valinfo->control / 8] &
2387 					(1 << ((valinfo->control % 8) - 1))))
2388 				continue;
2389 		} else { /* UAC_VERSION_2/3 */
2390 			if (!uac_v2v3_control_is_readable(controls[valinfo->control / 8],
2391 							  valinfo->control))
2392 				continue;
2393 		}
2394 
2395 		map = find_map(state->map, unitid, valinfo->control);
2396 		if (check_ignored_ctl(map))
2397 			continue;
2398 		cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2399 		if (!cval)
2400 			return -ENOMEM;
2401 		snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2402 		cval->control = valinfo->control;
2403 		cval->val_type = valinfo->val_type;
2404 		cval->channels = 1;
2405 
2406 		if (state->mixer->protocol > UAC_VERSION_1 &&
2407 		    !uac_v2v3_control_is_writeable(controls[valinfo->control / 8],
2408 						   valinfo->control))
2409 			cval->master_readonly = 1;
2410 
2411 		/* get min/max values */
2412 		switch (type) {
2413 		case UAC_PROCESS_UP_DOWNMIX: {
2414 			bool mode_sel = false;
2415 
2416 			switch (state->mixer->protocol) {
2417 			case UAC_VERSION_1:
2418 			case UAC_VERSION_2:
2419 			default:
2420 				if (cval->control == UAC_UD_MODE_SELECT)
2421 					mode_sel = true;
2422 				break;
2423 			case UAC_VERSION_3:
2424 				if (cval->control == UAC3_UD_MODE_SELECT)
2425 					mode_sel = true;
2426 				break;
2427 			}
2428 
2429 			if (mode_sel) {
2430 				__u8 *control_spec = uac_processing_unit_specific(desc,
2431 								state->mixer->protocol);
2432 				cval->min = 1;
2433 				cval->max = control_spec[0];
2434 				cval->res = 1;
2435 				cval->initialized = 1;
2436 				break;
2437 			}
2438 
2439 			get_min_max(cval, valinfo->min_value);
2440 			break;
2441 		}
2442 		case USB_XU_CLOCK_RATE:
2443 			/*
2444 			 * E-Mu USB 0404/0202/TrackerPre/0204
2445 			 * samplerate control quirk
2446 			 */
2447 			cval->min = 0;
2448 			cval->max = 5;
2449 			cval->res = 1;
2450 			cval->initialized = 1;
2451 			break;
2452 		default:
2453 			get_min_max(cval, valinfo->min_value);
2454 			break;
2455 		}
2456 
2457 		kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
2458 		if (!kctl) {
2459 			usb_mixer_elem_info_free(cval);
2460 			return -ENOMEM;
2461 		}
2462 		kctl->private_free = snd_usb_mixer_elem_free;
2463 
2464 		if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name))) {
2465 			/* nothing */ ;
2466 		} else if (info->name) {
2467 			strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
2468 		} else {
2469 			if (extension_unit)
2470 				nameid = uac_extension_unit_iExtension(desc, state->mixer->protocol);
2471 			else
2472 				nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
2473 			len = 0;
2474 			if (nameid)
2475 				len = snd_usb_copy_string_desc(state->chip,
2476 							       nameid,
2477 							       kctl->id.name,
2478 							       sizeof(kctl->id.name));
2479 			if (!len)
2480 				strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
2481 		}
2482 		append_ctl_name(kctl, " ");
2483 		append_ctl_name(kctl, valinfo->suffix);
2484 
2485 		usb_audio_dbg(state->chip,
2486 			      "[%d] PU [%s] ch = %d, val = %d/%d\n",
2487 			      cval->head.id, kctl->id.name, cval->channels,
2488 			      cval->min, cval->max);
2489 
2490 		err = snd_usb_mixer_add_control(&cval->head, kctl);
2491 		if (err < 0)
2492 			return err;
2493 	}
2494 	return 0;
2495 }
2496 
2497 static int parse_audio_processing_unit(struct mixer_build *state, int unitid,
2498 				       void *raw_desc)
2499 {
2500 	switch (state->mixer->protocol) {
2501 	case UAC_VERSION_1:
2502 	case UAC_VERSION_2:
2503 	default:
2504 		return build_audio_procunit(state, unitid, raw_desc,
2505 					    procunits, false);
2506 	case UAC_VERSION_3:
2507 		return build_audio_procunit(state, unitid, raw_desc,
2508 					    uac3_procunits, false);
2509 	}
2510 }
2511 
2512 static int parse_audio_extension_unit(struct mixer_build *state, int unitid,
2513 				      void *raw_desc)
2514 {
2515 	/*
2516 	 * Note that we parse extension units with processing unit descriptors.
2517 	 * That's ok as the layout is the same.
2518 	 */
2519 	return build_audio_procunit(state, unitid, raw_desc, extunits, true);
2520 }
2521 
2522 /*
2523  * Selector Unit
2524  */
2525 
2526 /*
2527  * info callback for selector unit
2528  * use an enumerator type for routing
2529  */
2530 static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol,
2531 				   struct snd_ctl_elem_info *uinfo)
2532 {
2533 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2534 	const char **itemlist = (const char **)kcontrol->private_value;
2535 
2536 	if (snd_BUG_ON(!itemlist))
2537 		return -EINVAL;
2538 	return snd_ctl_enum_info(uinfo, 1, cval->max, itemlist);
2539 }
2540 
2541 /* get callback for selector unit */
2542 static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol,
2543 				  struct snd_ctl_elem_value *ucontrol)
2544 {
2545 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2546 	int val, err;
2547 
2548 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2549 	if (err < 0) {
2550 		ucontrol->value.enumerated.item[0] = 0;
2551 		return filter_error(cval, err);
2552 	}
2553 	val = get_relative_value(cval, val);
2554 	ucontrol->value.enumerated.item[0] = val;
2555 	return 0;
2556 }
2557 
2558 /* put callback for selector unit */
2559 static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol,
2560 				  struct snd_ctl_elem_value *ucontrol)
2561 {
2562 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2563 	int val, oval, err;
2564 
2565 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2566 	if (err < 0)
2567 		return filter_error(cval, err);
2568 	val = ucontrol->value.enumerated.item[0];
2569 	val = get_abs_value(cval, val);
2570 	if (val != oval) {
2571 		set_cur_ctl_value(cval, cval->control << 8, val);
2572 		return 1;
2573 	}
2574 	return 0;
2575 }
2576 
2577 /* alsa control interface for selector unit */
2578 static const struct snd_kcontrol_new mixer_selectunit_ctl = {
2579 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2580 	.name = "", /* will be filled later */
2581 	.info = mixer_ctl_selector_info,
2582 	.get = mixer_ctl_selector_get,
2583 	.put = mixer_ctl_selector_put,
2584 };
2585 
2586 /*
2587  * private free callback.
2588  * free both private_data and private_value
2589  */
2590 static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
2591 {
2592 	int i, num_ins = 0;
2593 
2594 	if (kctl->private_data) {
2595 		struct usb_mixer_elem_info *cval = kctl->private_data;
2596 		num_ins = cval->max;
2597 		usb_mixer_elem_info_free(cval);
2598 		kctl->private_data = NULL;
2599 	}
2600 	if (kctl->private_value) {
2601 		char **itemlist = (char **)kctl->private_value;
2602 		for (i = 0; i < num_ins; i++)
2603 			kfree(itemlist[i]);
2604 		kfree(itemlist);
2605 		kctl->private_value = 0;
2606 	}
2607 }
2608 
2609 /*
2610  * parse a selector unit
2611  */
2612 static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
2613 				     void *raw_desc)
2614 {
2615 	struct uac_selector_unit_descriptor *desc = raw_desc;
2616 	unsigned int i, nameid, len;
2617 	int err;
2618 	struct usb_mixer_elem_info *cval;
2619 	struct snd_kcontrol *kctl;
2620 	const struct usbmix_name_map *map;
2621 	char **namelist;
2622 
2623 	for (i = 0; i < desc->bNrInPins; i++) {
2624 		err = parse_audio_unit(state, desc->baSourceID[i]);
2625 		if (err < 0)
2626 			return err;
2627 	}
2628 
2629 	if (desc->bNrInPins == 1) /* only one ? nonsense! */
2630 		return 0;
2631 
2632 	map = find_map(state->map, unitid, 0);
2633 	if (check_ignored_ctl(map))
2634 		return 0;
2635 
2636 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2637 	if (!cval)
2638 		return -ENOMEM;
2639 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2640 	cval->val_type = USB_MIXER_U8;
2641 	cval->channels = 1;
2642 	cval->min = 1;
2643 	cval->max = desc->bNrInPins;
2644 	cval->res = 1;
2645 	cval->initialized = 1;
2646 
2647 	switch (state->mixer->protocol) {
2648 	case UAC_VERSION_1:
2649 	default:
2650 		cval->control = 0;
2651 		break;
2652 	case UAC_VERSION_2:
2653 	case UAC_VERSION_3:
2654 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
2655 		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
2656 			cval->control = UAC2_CX_CLOCK_SELECTOR;
2657 		else /* UAC2/3_SELECTOR_UNIT */
2658 			cval->control = UAC2_SU_SELECTOR;
2659 		break;
2660 	}
2661 
2662 	namelist = kcalloc(desc->bNrInPins, sizeof(char *), GFP_KERNEL);
2663 	if (!namelist) {
2664 		err = -ENOMEM;
2665 		goto error_cval;
2666 	}
2667 #define MAX_ITEM_NAME_LEN	64
2668 	for (i = 0; i < desc->bNrInPins; i++) {
2669 		struct usb_audio_term iterm;
2670 		len = 0;
2671 		namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
2672 		if (!namelist[i]) {
2673 			err = -ENOMEM;
2674 			goto error_name;
2675 		}
2676 		len = check_mapped_selector_name(state, unitid, i, namelist[i],
2677 						 MAX_ITEM_NAME_LEN);
2678 		if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
2679 			len = get_term_name(state->chip, &iterm, namelist[i],
2680 					    MAX_ITEM_NAME_LEN, 0);
2681 		if (! len)
2682 			sprintf(namelist[i], "Input %u", i);
2683 	}
2684 
2685 	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
2686 	if (! kctl) {
2687 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2688 		err = -ENOMEM;
2689 		goto error_name;
2690 	}
2691 	kctl->private_value = (unsigned long)namelist;
2692 	kctl->private_free = usb_mixer_selector_elem_free;
2693 
2694 	/* check the static mapping table at first */
2695 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2696 	if (!len) {
2697 		/* no mapping ? */
2698 		switch (state->mixer->protocol) {
2699 		case UAC_VERSION_1:
2700 		case UAC_VERSION_2:
2701 		default:
2702 		/* if iSelector is given, use it */
2703 			nameid = uac_selector_unit_iSelector(desc);
2704 			if (nameid)
2705 				len = snd_usb_copy_string_desc(state->chip,
2706 							nameid, kctl->id.name,
2707 							sizeof(kctl->id.name));
2708 			break;
2709 		case UAC_VERSION_3:
2710 			/* TODO: Class-Specific strings not yet supported */
2711 			break;
2712 		}
2713 
2714 		/* ... or pick up the terminal name at next */
2715 		if (!len)
2716 			len = get_term_name(state->chip, &state->oterm,
2717 				    kctl->id.name, sizeof(kctl->id.name), 0);
2718 		/* ... or use the fixed string "USB" as the last resort */
2719 		if (!len)
2720 			strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
2721 
2722 		/* and add the proper suffix */
2723 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
2724 		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
2725 			append_ctl_name(kctl, " Clock Source");
2726 		else if ((state->oterm.type & 0xff00) == 0x0100)
2727 			append_ctl_name(kctl, " Capture Source");
2728 		else
2729 			append_ctl_name(kctl, " Playback Source");
2730 	}
2731 
2732 	usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
2733 		    cval->head.id, kctl->id.name, desc->bNrInPins);
2734 	return snd_usb_mixer_add_control(&cval->head, kctl);
2735 
2736  error_name:
2737 	for (i = 0; i < desc->bNrInPins; i++)
2738 		kfree(namelist[i]);
2739 	kfree(namelist);
2740  error_cval:
2741 	usb_mixer_elem_info_free(cval);
2742 	return err;
2743 }
2744 
2745 /*
2746  * parse an audio unit recursively
2747  */
2748 
2749 static int parse_audio_unit(struct mixer_build *state, int unitid)
2750 {
2751 	unsigned char *p1;
2752 	int protocol = state->mixer->protocol;
2753 
2754 	if (test_and_set_bit(unitid, state->unitbitmap))
2755 		return 0; /* the unit already visited */
2756 
2757 	p1 = find_audio_control_unit(state, unitid);
2758 	if (!p1) {
2759 		usb_audio_err(state->chip, "unit %d not found!\n", unitid);
2760 		return -EINVAL;
2761 	}
2762 
2763 	if (!snd_usb_validate_audio_desc(p1, protocol)) {
2764 		usb_audio_dbg(state->chip, "invalid unit %d\n", unitid);
2765 		return 0; /* skip invalid unit */
2766 	}
2767 
2768 	switch (PTYPE(protocol, p1[2])) {
2769 	case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):
2770 	case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):
2771 	case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):
2772 		return parse_audio_input_terminal(state, unitid, p1);
2773 	case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):
2774 	case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):
2775 	case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):
2776 		return parse_audio_mixer_unit(state, unitid, p1);
2777 	case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):
2778 	case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):
2779 		return parse_clock_source_unit(state, unitid, p1);
2780 	case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):
2781 	case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):
2782 	case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):
2783 	case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):
2784 	case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):
2785 		return parse_audio_selector_unit(state, unitid, p1);
2786 	case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):
2787 	case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):
2788 	case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT):
2789 		return parse_audio_feature_unit(state, unitid, p1);
2790 	case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):
2791 	case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):
2792 	case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):
2793 		return parse_audio_processing_unit(state, unitid, p1);
2794 	case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):
2795 	case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):
2796 	case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):
2797 		return parse_audio_extension_unit(state, unitid, p1);
2798 	case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):
2799 	case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):
2800 		return 0; /* FIXME - effect units not implemented yet */
2801 	default:
2802 		usb_audio_err(state->chip,
2803 			      "unit %u: unexpected type 0x%02x\n",
2804 			      unitid, p1[2]);
2805 		return -EINVAL;
2806 	}
2807 }
2808 
2809 static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
2810 {
2811 	/* kill pending URBs */
2812 	snd_usb_mixer_disconnect(mixer);
2813 
2814 	kfree(mixer->id_elems);
2815 	if (mixer->urb) {
2816 		kfree(mixer->urb->transfer_buffer);
2817 		usb_free_urb(mixer->urb);
2818 	}
2819 	usb_free_urb(mixer->rc_urb);
2820 	kfree(mixer->rc_setup_packet);
2821 	kfree(mixer);
2822 }
2823 
2824 static int snd_usb_mixer_dev_free(struct snd_device *device)
2825 {
2826 	struct usb_mixer_interface *mixer = device->device_data;
2827 	snd_usb_mixer_free(mixer);
2828 	return 0;
2829 }
2830 
2831 /* UAC3 predefined channels configuration */
2832 struct uac3_badd_profile {
2833 	int subclass;
2834 	const char *name;
2835 	int c_chmask;	/* capture channels mask */
2836 	int p_chmask;	/* playback channels mask */
2837 	int st_chmask;	/* side tone mixing channel mask */
2838 };
2839 
2840 static const struct uac3_badd_profile uac3_badd_profiles[] = {
2841 	{
2842 		/*
2843 		 * BAIF, BAOF or combination of both
2844 		 * IN: Mono or Stereo cfg, Mono alt possible
2845 		 * OUT: Mono or Stereo cfg, Mono alt possible
2846 		 */
2847 		.subclass = UAC3_FUNCTION_SUBCLASS_GENERIC_IO,
2848 		.name = "GENERIC IO",
2849 		.c_chmask = -1,		/* dynamic channels */
2850 		.p_chmask = -1,		/* dynamic channels */
2851 	},
2852 	{
2853 		/* BAOF; Stereo only cfg, Mono alt possible */
2854 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADPHONE,
2855 		.name = "HEADPHONE",
2856 		.p_chmask = 3,
2857 	},
2858 	{
2859 		/* BAOF; Mono or Stereo cfg, Mono alt possible */
2860 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKER,
2861 		.name = "SPEAKER",
2862 		.p_chmask = -1,		/* dynamic channels */
2863 	},
2864 	{
2865 		/* BAIF; Mono or Stereo cfg, Mono alt possible */
2866 		.subclass = UAC3_FUNCTION_SUBCLASS_MICROPHONE,
2867 		.name = "MICROPHONE",
2868 		.c_chmask = -1,		/* dynamic channels */
2869 	},
2870 	{
2871 		/*
2872 		 * BAIOF topology
2873 		 * IN: Mono only
2874 		 * OUT: Mono or Stereo cfg, Mono alt possible
2875 		 */
2876 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET,
2877 		.name = "HEADSET",
2878 		.c_chmask = 1,
2879 		.p_chmask = -1,		/* dynamic channels */
2880 		.st_chmask = 1,
2881 	},
2882 	{
2883 		/* BAIOF; IN: Mono only; OUT: Stereo only, Mono alt possible */
2884 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER,
2885 		.name = "HEADSET ADAPTER",
2886 		.c_chmask = 1,
2887 		.p_chmask = 3,
2888 		.st_chmask = 1,
2889 	},
2890 	{
2891 		/* BAIF + BAOF; IN: Mono only; OUT: Mono only */
2892 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE,
2893 		.name = "SPEAKERPHONE",
2894 		.c_chmask = 1,
2895 		.p_chmask = 1,
2896 	},
2897 	{ 0 } /* terminator */
2898 };
2899 
2900 static bool uac3_badd_func_has_valid_channels(struct usb_mixer_interface *mixer,
2901 					      const struct uac3_badd_profile *f,
2902 					      int c_chmask, int p_chmask)
2903 {
2904 	/*
2905 	 * If both playback/capture channels are dynamic, make sure
2906 	 * at least one channel is present
2907 	 */
2908 	if (f->c_chmask < 0 && f->p_chmask < 0) {
2909 		if (!c_chmask && !p_chmask) {
2910 			usb_audio_warn(mixer->chip, "BAAD %s: no channels?",
2911 				       f->name);
2912 			return false;
2913 		}
2914 		return true;
2915 	}
2916 
2917 	if ((f->c_chmask < 0 && !c_chmask) ||
2918 	    (f->c_chmask >= 0 && f->c_chmask != c_chmask)) {
2919 		usb_audio_warn(mixer->chip, "BAAD %s c_chmask mismatch",
2920 			       f->name);
2921 		return false;
2922 	}
2923 	if ((f->p_chmask < 0 && !p_chmask) ||
2924 	    (f->p_chmask >= 0 && f->p_chmask != p_chmask)) {
2925 		usb_audio_warn(mixer->chip, "BAAD %s p_chmask mismatch",
2926 			       f->name);
2927 		return false;
2928 	}
2929 	return true;
2930 }
2931 
2932 /*
2933  * create mixer controls for UAC3 BADD profiles
2934  *
2935  * UAC3 BADD device doesn't contain CS descriptors thus we will guess everything
2936  *
2937  * BADD device may contain Mixer Unit, which doesn't have any controls, skip it
2938  */
2939 static int snd_usb_mixer_controls_badd(struct usb_mixer_interface *mixer,
2940 				       int ctrlif)
2941 {
2942 	struct usb_device *dev = mixer->chip->dev;
2943 	struct usb_interface_assoc_descriptor *assoc;
2944 	int badd_profile = mixer->chip->badd_profile;
2945 	const struct uac3_badd_profile *f;
2946 	const struct usbmix_ctl_map *map;
2947 	int p_chmask = 0, c_chmask = 0, st_chmask = 0;
2948 	int i;
2949 
2950 	assoc = usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
2951 
2952 	/* Detect BADD capture/playback channels from AS EP descriptors */
2953 	for (i = 0; i < assoc->bInterfaceCount; i++) {
2954 		int intf = assoc->bFirstInterface + i;
2955 
2956 		struct usb_interface *iface;
2957 		struct usb_host_interface *alts;
2958 		struct usb_interface_descriptor *altsd;
2959 		unsigned int maxpacksize;
2960 		char dir_in;
2961 		int chmask, num;
2962 
2963 		if (intf == ctrlif)
2964 			continue;
2965 
2966 		iface = usb_ifnum_to_if(dev, intf);
2967 		if (!iface)
2968 			continue;
2969 
2970 		num = iface->num_altsetting;
2971 
2972 		if (num < 2)
2973 			return -EINVAL;
2974 
2975 		/*
2976 		 * The number of Channels in an AudioStreaming interface
2977 		 * and the audio sample bit resolution (16 bits or 24
2978 		 * bits) can be derived from the wMaxPacketSize field in
2979 		 * the Standard AS Audio Data Endpoint descriptor in
2980 		 * Alternate Setting 1
2981 		 */
2982 		alts = &iface->altsetting[1];
2983 		altsd = get_iface_desc(alts);
2984 
2985 		if (altsd->bNumEndpoints < 1)
2986 			return -EINVAL;
2987 
2988 		/* check direction */
2989 		dir_in = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN);
2990 		maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
2991 
2992 		switch (maxpacksize) {
2993 		default:
2994 			usb_audio_err(mixer->chip,
2995 				"incorrect wMaxPacketSize 0x%x for BADD profile\n",
2996 				maxpacksize);
2997 			return -EINVAL;
2998 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_16:
2999 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_16:
3000 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_24:
3001 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_24:
3002 			chmask = 1;
3003 			break;
3004 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_16:
3005 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_16:
3006 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_24:
3007 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_24:
3008 			chmask = 3;
3009 			break;
3010 		}
3011 
3012 		if (dir_in)
3013 			c_chmask = chmask;
3014 		else
3015 			p_chmask = chmask;
3016 	}
3017 
3018 	usb_audio_dbg(mixer->chip,
3019 		"UAC3 BADD profile 0x%x: detected c_chmask=%d p_chmask=%d\n",
3020 		badd_profile, c_chmask, p_chmask);
3021 
3022 	/* check the mapping table */
3023 	for (map = uac3_badd_usbmix_ctl_maps; map->id; map++) {
3024 		if (map->id == badd_profile)
3025 			break;
3026 	}
3027 
3028 	if (!map->id)
3029 		return -EINVAL;
3030 
3031 	for (f = uac3_badd_profiles; f->name; f++) {
3032 		if (badd_profile == f->subclass)
3033 			break;
3034 	}
3035 	if (!f->name)
3036 		return -EINVAL;
3037 	if (!uac3_badd_func_has_valid_channels(mixer, f, c_chmask, p_chmask))
3038 		return -EINVAL;
3039 	st_chmask = f->st_chmask;
3040 
3041 	/* Playback */
3042 	if (p_chmask) {
3043 		/* Master channel, always writable */
3044 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3045 				       UAC3_BADD_FU_ID2, map->map);
3046 		/* Mono/Stereo volume channels, always writable */
3047 		build_feature_ctl_badd(mixer, p_chmask, UAC_FU_VOLUME,
3048 				       UAC3_BADD_FU_ID2, map->map);
3049 	}
3050 
3051 	/* Capture */
3052 	if (c_chmask) {
3053 		/* Master channel, always writable */
3054 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3055 				       UAC3_BADD_FU_ID5, map->map);
3056 		/* Mono/Stereo volume channels, always writable */
3057 		build_feature_ctl_badd(mixer, c_chmask, UAC_FU_VOLUME,
3058 				       UAC3_BADD_FU_ID5, map->map);
3059 	}
3060 
3061 	/* Side tone-mixing */
3062 	if (st_chmask) {
3063 		/* Master channel, always writable */
3064 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3065 				       UAC3_BADD_FU_ID7, map->map);
3066 		/* Mono volume channel, always writable */
3067 		build_feature_ctl_badd(mixer, 1, UAC_FU_VOLUME,
3068 				       UAC3_BADD_FU_ID7, map->map);
3069 	}
3070 
3071 	/* Insertion Control */
3072 	if (f->subclass == UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER) {
3073 		struct usb_audio_term iterm, oterm;
3074 
3075 		/* Input Term - Insertion control */
3076 		memset(&iterm, 0, sizeof(iterm));
3077 		iterm.id = UAC3_BADD_IT_ID4;
3078 		iterm.type = UAC_BIDIR_TERMINAL_HEADSET;
3079 		build_connector_control(mixer, map->map, &iterm, true);
3080 
3081 		/* Output Term - Insertion control */
3082 		memset(&oterm, 0, sizeof(oterm));
3083 		oterm.id = UAC3_BADD_OT_ID3;
3084 		oterm.type = UAC_BIDIR_TERMINAL_HEADSET;
3085 		build_connector_control(mixer, map->map, &oterm, false);
3086 	}
3087 
3088 	return 0;
3089 }
3090 
3091 /*
3092  * create mixer controls
3093  *
3094  * walk through all UAC_OUTPUT_TERMINAL descriptors to search for mixers
3095  */
3096 static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
3097 {
3098 	struct mixer_build state;
3099 	int err;
3100 	const struct usbmix_ctl_map *map;
3101 	void *p;
3102 
3103 	memset(&state, 0, sizeof(state));
3104 	state.chip = mixer->chip;
3105 	state.mixer = mixer;
3106 	state.buffer = mixer->hostif->extra;
3107 	state.buflen = mixer->hostif->extralen;
3108 
3109 	/* check the mapping table */
3110 	for (map = usbmix_ctl_maps; map->id; map++) {
3111 		if (map->id == state.chip->usb_id) {
3112 			state.map = map->map;
3113 			state.selector_map = map->selector_map;
3114 			mixer->ignore_ctl_error |= map->ignore_ctl_error;
3115 			break;
3116 		}
3117 	}
3118 
3119 	p = NULL;
3120 	while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
3121 					    mixer->hostif->extralen,
3122 					    p, UAC_OUTPUT_TERMINAL)) != NULL) {
3123 		if (!snd_usb_validate_audio_desc(p, mixer->protocol))
3124 			continue; /* skip invalid descriptor */
3125 
3126 		if (mixer->protocol == UAC_VERSION_1) {
3127 			struct uac1_output_terminal_descriptor *desc = p;
3128 
3129 			/* mark terminal ID as visited */
3130 			set_bit(desc->bTerminalID, state.unitbitmap);
3131 			state.oterm.id = desc->bTerminalID;
3132 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3133 			state.oterm.name = desc->iTerminal;
3134 			err = parse_audio_unit(&state, desc->bSourceID);
3135 			if (err < 0 && err != -EINVAL)
3136 				return err;
3137 		} else if (mixer->protocol == UAC_VERSION_2) {
3138 			struct uac2_output_terminal_descriptor *desc = p;
3139 
3140 			/* mark terminal ID as visited */
3141 			set_bit(desc->bTerminalID, state.unitbitmap);
3142 			state.oterm.id = desc->bTerminalID;
3143 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3144 			state.oterm.name = desc->iTerminal;
3145 			err = parse_audio_unit(&state, desc->bSourceID);
3146 			if (err < 0 && err != -EINVAL)
3147 				return err;
3148 
3149 			/*
3150 			 * For UAC2, use the same approach to also add the
3151 			 * clock selectors
3152 			 */
3153 			err = parse_audio_unit(&state, desc->bCSourceID);
3154 			if (err < 0 && err != -EINVAL)
3155 				return err;
3156 
3157 			if ((state.oterm.type & 0xff00) != 0x0100 &&
3158 			    uac_v2v3_control_is_readable(le16_to_cpu(desc->bmControls),
3159 							 UAC2_TE_CONNECTOR)) {
3160 				build_connector_control(state.mixer, state.map,
3161 							&state.oterm, false);
3162 			}
3163 		} else {  /* UAC_VERSION_3 */
3164 			struct uac3_output_terminal_descriptor *desc = p;
3165 
3166 			/* mark terminal ID as visited */
3167 			set_bit(desc->bTerminalID, state.unitbitmap);
3168 			state.oterm.id = desc->bTerminalID;
3169 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3170 			state.oterm.name = le16_to_cpu(desc->wTerminalDescrStr);
3171 			err = parse_audio_unit(&state, desc->bSourceID);
3172 			if (err < 0 && err != -EINVAL)
3173 				return err;
3174 
3175 			/*
3176 			 * For UAC3, use the same approach to also add the
3177 			 * clock selectors
3178 			 */
3179 			err = parse_audio_unit(&state, desc->bCSourceID);
3180 			if (err < 0 && err != -EINVAL)
3181 				return err;
3182 
3183 			if ((state.oterm.type & 0xff00) != 0x0100 &&
3184 			    uac_v2v3_control_is_readable(le32_to_cpu(desc->bmControls),
3185 							 UAC3_TE_INSERTION)) {
3186 				build_connector_control(state.mixer, state.map,
3187 							&state.oterm, false);
3188 			}
3189 		}
3190 	}
3191 
3192 	return 0;
3193 }
3194 
3195 void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
3196 {
3197 	struct usb_mixer_elem_list *list;
3198 
3199 	for_each_mixer_elem(list, mixer, unitid) {
3200 		struct usb_mixer_elem_info *info =
3201 			mixer_elem_list_to_info(list);
3202 		/* invalidate cache, so the value is read from the device */
3203 		info->cached = 0;
3204 		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3205 			       &list->kctl->id);
3206 	}
3207 }
3208 
3209 static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
3210 				    struct usb_mixer_elem_list *list)
3211 {
3212 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3213 	static const char * const val_types[] = {"BOOLEAN", "INV_BOOLEAN",
3214 				    "S8", "U8", "S16", "U16"};
3215 	snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
3216 			    "channels=%i, type=\"%s\"\n", cval->head.id,
3217 			    cval->control, cval->cmask, cval->channels,
3218 			    val_types[cval->val_type]);
3219 	snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
3220 			    cval->min, cval->max, cval->dBmin, cval->dBmax);
3221 }
3222 
3223 static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
3224 				    struct snd_info_buffer *buffer)
3225 {
3226 	struct snd_usb_audio *chip = entry->private_data;
3227 	struct usb_mixer_interface *mixer;
3228 	struct usb_mixer_elem_list *list;
3229 	int unitid;
3230 
3231 	list_for_each_entry(mixer, &chip->mixer_list, list) {
3232 		snd_iprintf(buffer,
3233 			"USB Mixer: usb_id=0x%08x, ctrlif=%i, ctlerr=%i\n",
3234 				chip->usb_id, mixer_ctrl_intf(mixer),
3235 				mixer->ignore_ctl_error);
3236 		snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
3237 		for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
3238 			for_each_mixer_elem(list, mixer, unitid) {
3239 				snd_iprintf(buffer, "  Unit: %i\n", list->id);
3240 				if (list->kctl)
3241 					snd_iprintf(buffer,
3242 						    "    Control: name=\"%s\", index=%i\n",
3243 						    list->kctl->id.name,
3244 						    list->kctl->id.index);
3245 				if (list->dump)
3246 					list->dump(buffer, list);
3247 			}
3248 		}
3249 	}
3250 }
3251 
3252 static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
3253 				       int attribute, int value, int index)
3254 {
3255 	struct usb_mixer_elem_list *list;
3256 	__u8 unitid = (index >> 8) & 0xff;
3257 	__u8 control = (value >> 8) & 0xff;
3258 	__u8 channel = value & 0xff;
3259 	unsigned int count = 0;
3260 
3261 	if (channel >= MAX_CHANNELS) {
3262 		usb_audio_dbg(mixer->chip,
3263 			"%s(): bogus channel number %d\n",
3264 			__func__, channel);
3265 		return;
3266 	}
3267 
3268 	for_each_mixer_elem(list, mixer, unitid)
3269 		count++;
3270 
3271 	if (count == 0)
3272 		return;
3273 
3274 	for_each_mixer_elem(list, mixer, unitid) {
3275 		struct usb_mixer_elem_info *info;
3276 
3277 		if (!list->kctl)
3278 			continue;
3279 
3280 		info = mixer_elem_list_to_info(list);
3281 		if (count > 1 && info->control != control)
3282 			continue;
3283 
3284 		switch (attribute) {
3285 		case UAC2_CS_CUR:
3286 			/* invalidate cache, so the value is read from the device */
3287 			if (channel)
3288 				info->cached &= ~(1 << channel);
3289 			else /* master channel */
3290 				info->cached = 0;
3291 
3292 			snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3293 				       &info->head.kctl->id);
3294 			break;
3295 
3296 		case UAC2_CS_RANGE:
3297 			/* TODO */
3298 			break;
3299 
3300 		case UAC2_CS_MEM:
3301 			/* TODO */
3302 			break;
3303 
3304 		default:
3305 			usb_audio_dbg(mixer->chip,
3306 				"unknown attribute %d in interrupt\n",
3307 				attribute);
3308 			break;
3309 		} /* switch */
3310 	}
3311 }
3312 
3313 static void snd_usb_mixer_interrupt(struct urb *urb)
3314 {
3315 	struct usb_mixer_interface *mixer = urb->context;
3316 	int len = urb->actual_length;
3317 	int ustatus = urb->status;
3318 
3319 	if (ustatus != 0)
3320 		goto requeue;
3321 
3322 	if (mixer->protocol == UAC_VERSION_1) {
3323 		struct uac1_status_word *status;
3324 
3325 		for (status = urb->transfer_buffer;
3326 		     len >= sizeof(*status);
3327 		     len -= sizeof(*status), status++) {
3328 			dev_dbg(&urb->dev->dev, "status interrupt: %02x %02x\n",
3329 						status->bStatusType,
3330 						status->bOriginator);
3331 
3332 			/* ignore any notifications not from the control interface */
3333 			if ((status->bStatusType & UAC1_STATUS_TYPE_ORIG_MASK) !=
3334 				UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF)
3335 				continue;
3336 
3337 			if (status->bStatusType & UAC1_STATUS_TYPE_MEM_CHANGED)
3338 				snd_usb_mixer_rc_memory_change(mixer, status->bOriginator);
3339 			else
3340 				snd_usb_mixer_notify_id(mixer, status->bOriginator);
3341 		}
3342 	} else { /* UAC_VERSION_2 */
3343 		struct uac2_interrupt_data_msg *msg;
3344 
3345 		for (msg = urb->transfer_buffer;
3346 		     len >= sizeof(*msg);
3347 		     len -= sizeof(*msg), msg++) {
3348 			/* drop vendor specific and endpoint requests */
3349 			if ((msg->bInfo & UAC2_INTERRUPT_DATA_MSG_VENDOR) ||
3350 			    (msg->bInfo & UAC2_INTERRUPT_DATA_MSG_EP))
3351 				continue;
3352 
3353 			snd_usb_mixer_interrupt_v2(mixer, msg->bAttribute,
3354 						   le16_to_cpu(msg->wValue),
3355 						   le16_to_cpu(msg->wIndex));
3356 		}
3357 	}
3358 
3359 requeue:
3360 	if (ustatus != -ENOENT &&
3361 	    ustatus != -ECONNRESET &&
3362 	    ustatus != -ESHUTDOWN) {
3363 		urb->dev = mixer->chip->dev;
3364 		usb_submit_urb(urb, GFP_ATOMIC);
3365 	}
3366 }
3367 
3368 /* create the handler for the optional status interrupt endpoint */
3369 static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
3370 {
3371 	struct usb_endpoint_descriptor *ep;
3372 	void *transfer_buffer;
3373 	int buffer_length;
3374 	unsigned int epnum;
3375 
3376 	/* we need one interrupt input endpoint */
3377 	if (get_iface_desc(mixer->hostif)->bNumEndpoints < 1)
3378 		return 0;
3379 	ep = get_endpoint(mixer->hostif, 0);
3380 	if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_int(ep))
3381 		return 0;
3382 
3383 	epnum = usb_endpoint_num(ep);
3384 	buffer_length = le16_to_cpu(ep->wMaxPacketSize);
3385 	transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
3386 	if (!transfer_buffer)
3387 		return -ENOMEM;
3388 	mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
3389 	if (!mixer->urb) {
3390 		kfree(transfer_buffer);
3391 		return -ENOMEM;
3392 	}
3393 	usb_fill_int_urb(mixer->urb, mixer->chip->dev,
3394 			 usb_rcvintpipe(mixer->chip->dev, epnum),
3395 			 transfer_buffer, buffer_length,
3396 			 snd_usb_mixer_interrupt, mixer, ep->bInterval);
3397 	usb_submit_urb(mixer->urb, GFP_KERNEL);
3398 	return 0;
3399 }
3400 
3401 static int keep_iface_ctl_get(struct snd_kcontrol *kcontrol,
3402 			      struct snd_ctl_elem_value *ucontrol)
3403 {
3404 	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
3405 
3406 	ucontrol->value.integer.value[0] = mixer->chip->keep_iface;
3407 	return 0;
3408 }
3409 
3410 static int keep_iface_ctl_put(struct snd_kcontrol *kcontrol,
3411 			      struct snd_ctl_elem_value *ucontrol)
3412 {
3413 	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
3414 	bool keep_iface = !!ucontrol->value.integer.value[0];
3415 
3416 	if (mixer->chip->keep_iface == keep_iface)
3417 		return 0;
3418 	mixer->chip->keep_iface = keep_iface;
3419 	return 1;
3420 }
3421 
3422 static const struct snd_kcontrol_new keep_iface_ctl = {
3423 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
3424 	.name = "Keep Interface",
3425 	.info = snd_ctl_boolean_mono_info,
3426 	.get = keep_iface_ctl_get,
3427 	.put = keep_iface_ctl_put,
3428 };
3429 
3430 static int create_keep_iface_ctl(struct usb_mixer_interface *mixer)
3431 {
3432 	struct snd_kcontrol *kctl = snd_ctl_new1(&keep_iface_ctl, mixer);
3433 
3434 	/* need only one control per card */
3435 	if (snd_ctl_find_id(mixer->chip->card, &kctl->id)) {
3436 		snd_ctl_free_one(kctl);
3437 		return 0;
3438 	}
3439 
3440 	return snd_ctl_add(mixer->chip->card, kctl);
3441 }
3442 
3443 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
3444 			 int ignore_error)
3445 {
3446 	static const struct snd_device_ops dev_ops = {
3447 		.dev_free = snd_usb_mixer_dev_free
3448 	};
3449 	struct usb_mixer_interface *mixer;
3450 	int err;
3451 
3452 	strcpy(chip->card->mixername, "USB Mixer");
3453 
3454 	mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
3455 	if (!mixer)
3456 		return -ENOMEM;
3457 	mixer->chip = chip;
3458 	mixer->ignore_ctl_error = ignore_error;
3459 	mixer->id_elems = kcalloc(MAX_ID_ELEMS, sizeof(*mixer->id_elems),
3460 				  GFP_KERNEL);
3461 	if (!mixer->id_elems) {
3462 		kfree(mixer);
3463 		return -ENOMEM;
3464 	}
3465 
3466 	mixer->hostif = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
3467 	switch (get_iface_desc(mixer->hostif)->bInterfaceProtocol) {
3468 	case UAC_VERSION_1:
3469 	default:
3470 		mixer->protocol = UAC_VERSION_1;
3471 		break;
3472 	case UAC_VERSION_2:
3473 		mixer->protocol = UAC_VERSION_2;
3474 		break;
3475 	case UAC_VERSION_3:
3476 		mixer->protocol = UAC_VERSION_3;
3477 		break;
3478 	}
3479 
3480 	if (mixer->protocol == UAC_VERSION_3 &&
3481 			chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
3482 		err = snd_usb_mixer_controls_badd(mixer, ctrlif);
3483 		if (err < 0)
3484 			goto _error;
3485 	} else {
3486 		err = snd_usb_mixer_controls(mixer);
3487 		if (err < 0)
3488 			goto _error;
3489 	}
3490 
3491 	err = snd_usb_mixer_status_create(mixer);
3492 	if (err < 0)
3493 		goto _error;
3494 
3495 	err = create_keep_iface_ctl(mixer);
3496 	if (err < 0)
3497 		goto _error;
3498 
3499 	err = snd_usb_mixer_apply_create_quirk(mixer);
3500 	if (err < 0)
3501 		goto _error;
3502 
3503 	err = snd_device_new(chip->card, SNDRV_DEV_CODEC, mixer, &dev_ops);
3504 	if (err < 0)
3505 		goto _error;
3506 
3507 	if (list_empty(&chip->mixer_list))
3508 		snd_card_ro_proc_new(chip->card, "usbmixer", chip,
3509 				     snd_usb_mixer_proc_read);
3510 
3511 	list_add(&mixer->list, &chip->mixer_list);
3512 	return 0;
3513 
3514 _error:
3515 	snd_usb_mixer_free(mixer);
3516 	return err;
3517 }
3518 
3519 void snd_usb_mixer_disconnect(struct usb_mixer_interface *mixer)
3520 {
3521 	if (mixer->disconnected)
3522 		return;
3523 	if (mixer->urb)
3524 		usb_kill_urb(mixer->urb);
3525 	if (mixer->rc_urb)
3526 		usb_kill_urb(mixer->rc_urb);
3527 	if (mixer->private_free)
3528 		mixer->private_free(mixer);
3529 	mixer->disconnected = true;
3530 }
3531 
3532 #ifdef CONFIG_PM
3533 /* stop any bus activity of a mixer */
3534 static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
3535 {
3536 	usb_kill_urb(mixer->urb);
3537 	usb_kill_urb(mixer->rc_urb);
3538 }
3539 
3540 static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
3541 {
3542 	int err;
3543 
3544 	if (mixer->urb) {
3545 		err = usb_submit_urb(mixer->urb, GFP_NOIO);
3546 		if (err < 0)
3547 			return err;
3548 	}
3549 
3550 	return 0;
3551 }
3552 
3553 int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
3554 {
3555 	snd_usb_mixer_inactivate(mixer);
3556 	if (mixer->private_suspend)
3557 		mixer->private_suspend(mixer);
3558 	return 0;
3559 }
3560 
3561 static int restore_mixer_value(struct usb_mixer_elem_list *list)
3562 {
3563 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3564 	int c, err, idx;
3565 
3566 	if (cval->cmask) {
3567 		idx = 0;
3568 		for (c = 0; c < MAX_CHANNELS; c++) {
3569 			if (!(cval->cmask & (1 << c)))
3570 				continue;
3571 			if (cval->cached & (1 << (c + 1))) {
3572 				err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
3573 							cval->cache_val[idx]);
3574 				if (err < 0)
3575 					return err;
3576 			}
3577 			idx++;
3578 		}
3579 	} else {
3580 		/* master */
3581 		if (cval->cached) {
3582 			err = snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
3583 			if (err < 0)
3584 				return err;
3585 		}
3586 	}
3587 
3588 	return 0;
3589 }
3590 
3591 int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume)
3592 {
3593 	struct usb_mixer_elem_list *list;
3594 	int id, err;
3595 
3596 	if (reset_resume) {
3597 		/* restore cached mixer values */
3598 		for (id = 0; id < MAX_ID_ELEMS; id++) {
3599 			for_each_mixer_elem(list, mixer, id) {
3600 				if (list->resume) {
3601 					err = list->resume(list);
3602 					if (err < 0)
3603 						return err;
3604 				}
3605 			}
3606 		}
3607 	}
3608 
3609 	snd_usb_mixer_resume_quirk(mixer);
3610 
3611 	return snd_usb_mixer_activate(mixer);
3612 }
3613 #endif
3614 
3615 void snd_usb_mixer_elem_init_std(struct usb_mixer_elem_list *list,
3616 				 struct usb_mixer_interface *mixer,
3617 				 int unitid)
3618 {
3619 	list->mixer = mixer;
3620 	list->id = unitid;
3621 	list->dump = snd_usb_mixer_dump_cval;
3622 #ifdef CONFIG_PM
3623 	list->resume = restore_mixer_value;
3624 #endif
3625 }
3626