xref: /openbmc/linux/sound/usb/mixer.c (revision ecefa105)
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 	int len;
119 
120 	if (!p || !p->name)
121 		return 0;
122 
123 	buflen--;
124 	len = strscpy(buf, p->name, buflen);
125 	return len < 0 ? buflen : len;
126 }
127 
128 /* ignore the error value if ignore_ctl_error flag is set */
129 #define filter_error(cval, err) \
130 	((cval)->head.mixer->ignore_ctl_error ? 0 : (err))
131 
132 /* check whether the control should be ignored */
133 static inline int
134 check_ignored_ctl(const struct usbmix_name_map *p)
135 {
136 	if (!p || p->name || p->dB)
137 		return 0;
138 	return 1;
139 }
140 
141 /* dB mapping */
142 static inline void check_mapped_dB(const struct usbmix_name_map *p,
143 				   struct usb_mixer_elem_info *cval)
144 {
145 	if (p && p->dB) {
146 		cval->dBmin = p->dB->min;
147 		cval->dBmax = p->dB->max;
148 		cval->min_mute = p->dB->min_mute;
149 		cval->initialized = 1;
150 	}
151 }
152 
153 /* get the mapped selector source name */
154 static int check_mapped_selector_name(struct mixer_build *state, int unitid,
155 				      int index, char *buf, int buflen)
156 {
157 	const struct usbmix_selector_map *p;
158 	int len;
159 
160 	if (!state->selector_map)
161 		return 0;
162 	for (p = state->selector_map; p->id; p++) {
163 		if (p->id == unitid && index < p->count) {
164 			len = strscpy(buf, p->names[index], buflen);
165 			return len < 0 ? buflen : len;
166 		}
167 	}
168 	return 0;
169 }
170 
171 /*
172  * find an audio control unit with the given unit id
173  */
174 static void *find_audio_control_unit(struct mixer_build *state,
175 				     unsigned char unit)
176 {
177 	/* we just parse the header */
178 	struct uac_feature_unit_descriptor *hdr = NULL;
179 
180 	while ((hdr = snd_usb_find_desc(state->buffer, state->buflen, hdr,
181 					USB_DT_CS_INTERFACE)) != NULL) {
182 		if (hdr->bLength >= 4 &&
183 		    hdr->bDescriptorSubtype >= UAC_INPUT_TERMINAL &&
184 		    hdr->bDescriptorSubtype <= UAC3_SAMPLE_RATE_CONVERTER &&
185 		    hdr->bUnitID == unit)
186 			return hdr;
187 	}
188 
189 	return NULL;
190 }
191 
192 /*
193  * copy a string with the given id
194  */
195 static int snd_usb_copy_string_desc(struct snd_usb_audio *chip,
196 				    int index, char *buf, int maxlen)
197 {
198 	int len = usb_string(chip->dev, index, buf, maxlen - 1);
199 
200 	if (len < 0)
201 		return 0;
202 
203 	buf[len] = 0;
204 	return len;
205 }
206 
207 /*
208  * convert from the byte/word on usb descriptor to the zero-based integer
209  */
210 static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
211 {
212 	switch (cval->val_type) {
213 	case USB_MIXER_BOOLEAN:
214 		return !!val;
215 	case USB_MIXER_INV_BOOLEAN:
216 		return !val;
217 	case USB_MIXER_U8:
218 		val &= 0xff;
219 		break;
220 	case USB_MIXER_S8:
221 		val &= 0xff;
222 		if (val >= 0x80)
223 			val -= 0x100;
224 		break;
225 	case USB_MIXER_U16:
226 		val &= 0xffff;
227 		break;
228 	case USB_MIXER_S16:
229 		val &= 0xffff;
230 		if (val >= 0x8000)
231 			val -= 0x10000;
232 		break;
233 	}
234 	return val;
235 }
236 
237 /*
238  * convert from the zero-based int to the byte/word for usb descriptor
239  */
240 static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
241 {
242 	switch (cval->val_type) {
243 	case USB_MIXER_BOOLEAN:
244 		return !!val;
245 	case USB_MIXER_INV_BOOLEAN:
246 		return !val;
247 	case USB_MIXER_S8:
248 	case USB_MIXER_U8:
249 		return val & 0xff;
250 	case USB_MIXER_S16:
251 	case USB_MIXER_U16:
252 		return val & 0xffff;
253 	}
254 	return 0; /* not reached */
255 }
256 
257 static int get_relative_value(struct usb_mixer_elem_info *cval, int val)
258 {
259 	if (!cval->res)
260 		cval->res = 1;
261 	if (val < cval->min)
262 		return 0;
263 	else if (val >= cval->max)
264 		return DIV_ROUND_UP(cval->max - cval->min, cval->res);
265 	else
266 		return (val - cval->min) / cval->res;
267 }
268 
269 static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
270 {
271 	if (val < 0)
272 		return cval->min;
273 	if (!cval->res)
274 		cval->res = 1;
275 	val *= cval->res;
276 	val += cval->min;
277 	if (val > cval->max)
278 		return cval->max;
279 	return val;
280 }
281 
282 static int uac2_ctl_value_size(int val_type)
283 {
284 	switch (val_type) {
285 	case USB_MIXER_S32:
286 	case USB_MIXER_U32:
287 		return 4;
288 	case USB_MIXER_S16:
289 	case USB_MIXER_U16:
290 		return 2;
291 	default:
292 		return 1;
293 	}
294 	return 0; /* unreachable */
295 }
296 
297 
298 /*
299  * retrieve a mixer value
300  */
301 
302 static inline int mixer_ctrl_intf(struct usb_mixer_interface *mixer)
303 {
304 	return get_iface_desc(mixer->hostif)->bInterfaceNumber;
305 }
306 
307 static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request,
308 			    int validx, int *value_ret)
309 {
310 	struct snd_usb_audio *chip = cval->head.mixer->chip;
311 	unsigned char buf[2];
312 	int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
313 	int timeout = 10;
314 	int idx = 0, err;
315 
316 	err = snd_usb_lock_shutdown(chip);
317 	if (err < 0)
318 		return -EIO;
319 
320 	while (timeout-- > 0) {
321 		idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
322 		err = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
323 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
324 				      validx, idx, buf, val_len);
325 		if (err >= val_len) {
326 			*value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
327 			err = 0;
328 			goto out;
329 		} else if (err == -ETIMEDOUT) {
330 			goto out;
331 		}
332 	}
333 	usb_audio_dbg(chip,
334 		"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
335 		request, validx, idx, cval->val_type);
336 	err = -EINVAL;
337 
338  out:
339 	snd_usb_unlock_shutdown(chip);
340 	return err;
341 }
342 
343 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
344 			    int validx, int *value_ret)
345 {
346 	struct snd_usb_audio *chip = cval->head.mixer->chip;
347 	/* enough space for one range */
348 	unsigned char buf[sizeof(__u16) + 3 * sizeof(__u32)];
349 	unsigned char *val;
350 	int idx = 0, ret, val_size, size;
351 	__u8 bRequest;
352 
353 	val_size = uac2_ctl_value_size(cval->val_type);
354 
355 	if (request == UAC_GET_CUR) {
356 		bRequest = UAC2_CS_CUR;
357 		size = val_size;
358 	} else {
359 		bRequest = UAC2_CS_RANGE;
360 		size = sizeof(__u16) + 3 * val_size;
361 	}
362 
363 	memset(buf, 0, sizeof(buf));
364 
365 	if (snd_usb_lock_shutdown(chip))
366 		return -EIO;
367 
368 	idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
369 	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
370 			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
371 			      validx, idx, buf, size);
372 	snd_usb_unlock_shutdown(chip);
373 
374 	if (ret < 0) {
375 		usb_audio_dbg(chip,
376 			"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
377 			request, validx, idx, cval->val_type);
378 		return ret;
379 	}
380 
381 	/* FIXME: how should we handle multiple triplets here? */
382 
383 	switch (request) {
384 	case UAC_GET_CUR:
385 		val = buf;
386 		break;
387 	case UAC_GET_MIN:
388 		val = buf + sizeof(__u16);
389 		break;
390 	case UAC_GET_MAX:
391 		val = buf + sizeof(__u16) + val_size;
392 		break;
393 	case UAC_GET_RES:
394 		val = buf + sizeof(__u16) + val_size * 2;
395 		break;
396 	default:
397 		return -EINVAL;
398 	}
399 
400 	*value_ret = convert_signed_value(cval,
401 					  snd_usb_combine_bytes(val, val_size));
402 
403 	return 0;
404 }
405 
406 static int get_ctl_value(struct usb_mixer_elem_info *cval, int request,
407 			 int validx, int *value_ret)
408 {
409 	validx += cval->idx_off;
410 
411 	return (cval->head.mixer->protocol == UAC_VERSION_1) ?
412 		get_ctl_value_v1(cval, request, validx, value_ret) :
413 		get_ctl_value_v2(cval, request, validx, value_ret);
414 }
415 
416 static int get_cur_ctl_value(struct usb_mixer_elem_info *cval,
417 			     int validx, int *value)
418 {
419 	return get_ctl_value(cval, UAC_GET_CUR, validx, value);
420 }
421 
422 /* channel = 0: master, 1 = first channel */
423 static inline int get_cur_mix_raw(struct usb_mixer_elem_info *cval,
424 				  int channel, int *value)
425 {
426 	return get_ctl_value(cval, UAC_GET_CUR,
427 			     (cval->control << 8) | channel,
428 			     value);
429 }
430 
431 int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
432 			     int channel, int index, int *value)
433 {
434 	int err;
435 
436 	if (cval->cached & (1 << channel)) {
437 		*value = cval->cache_val[index];
438 		return 0;
439 	}
440 	err = get_cur_mix_raw(cval, channel, value);
441 	if (err < 0) {
442 		if (!cval->head.mixer->ignore_ctl_error)
443 			usb_audio_dbg(cval->head.mixer->chip,
444 				"cannot get current value for control %d ch %d: err = %d\n",
445 				      cval->control, channel, err);
446 		return err;
447 	}
448 	cval->cached |= 1 << channel;
449 	cval->cache_val[index] = *value;
450 	return 0;
451 }
452 
453 /*
454  * set a mixer value
455  */
456 
457 int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
458 				int request, int validx, int value_set)
459 {
460 	struct snd_usb_audio *chip = cval->head.mixer->chip;
461 	unsigned char buf[4];
462 	int idx = 0, val_len, err, timeout = 10;
463 
464 	validx += cval->idx_off;
465 
466 
467 	if (cval->head.mixer->protocol == UAC_VERSION_1) {
468 		val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
469 	} else { /* UAC_VERSION_2/3 */
470 		val_len = uac2_ctl_value_size(cval->val_type);
471 
472 		/* FIXME */
473 		if (request != UAC_SET_CUR) {
474 			usb_audio_dbg(chip, "RANGE setting not yet supported\n");
475 			return -EINVAL;
476 		}
477 
478 		request = UAC2_CS_CUR;
479 	}
480 
481 	value_set = convert_bytes_value(cval, value_set);
482 	buf[0] = value_set & 0xff;
483 	buf[1] = (value_set >> 8) & 0xff;
484 	buf[2] = (value_set >> 16) & 0xff;
485 	buf[3] = (value_set >> 24) & 0xff;
486 
487 	err = snd_usb_lock_shutdown(chip);
488 	if (err < 0)
489 		return -EIO;
490 
491 	while (timeout-- > 0) {
492 		idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
493 		err = snd_usb_ctl_msg(chip->dev,
494 				      usb_sndctrlpipe(chip->dev, 0), request,
495 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
496 				      validx, idx, buf, val_len);
497 		if (err >= 0) {
498 			err = 0;
499 			goto out;
500 		} else if (err == -ETIMEDOUT) {
501 			goto out;
502 		}
503 	}
504 	usb_audio_dbg(chip, "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
505 		      request, validx, idx, cval->val_type, buf[0], buf[1]);
506 	err = -EINVAL;
507 
508  out:
509 	snd_usb_unlock_shutdown(chip);
510 	return err;
511 }
512 
513 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval,
514 			     int validx, int value)
515 {
516 	return snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, validx, value);
517 }
518 
519 int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
520 			     int index, int value)
521 {
522 	int err;
523 	unsigned int read_only = (channel == 0) ?
524 		cval->master_readonly :
525 		cval->ch_readonly & (1 << (channel - 1));
526 
527 	if (read_only) {
528 		usb_audio_dbg(cval->head.mixer->chip,
529 			      "%s(): channel %d of control %d is read_only\n",
530 			    __func__, channel, cval->control);
531 		return 0;
532 	}
533 
534 	err = snd_usb_mixer_set_ctl_value(cval,
535 					  UAC_SET_CUR, (cval->control << 8) | channel,
536 					  value);
537 	if (err < 0)
538 		return err;
539 	cval->cached |= 1 << channel;
540 	cval->cache_val[index] = value;
541 	return 0;
542 }
543 
544 /*
545  * TLV callback for mixer volume controls
546  */
547 int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
548 			 unsigned int size, unsigned int __user *_tlv)
549 {
550 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
551 	DECLARE_TLV_DB_MINMAX(scale, 0, 0);
552 
553 	if (size < sizeof(scale))
554 		return -ENOMEM;
555 	if (cval->min_mute)
556 		scale[0] = SNDRV_CTL_TLVT_DB_MINMAX_MUTE;
557 	scale[2] = cval->dBmin;
558 	scale[3] = cval->dBmax;
559 	if (copy_to_user(_tlv, scale, sizeof(scale)))
560 		return -EFAULT;
561 	return 0;
562 }
563 
564 /*
565  * parser routines begin here...
566  */
567 
568 static int parse_audio_unit(struct mixer_build *state, int unitid);
569 
570 
571 /*
572  * check if the input/output channel routing is enabled on the given bitmap.
573  * used for mixer unit parser
574  */
575 static int check_matrix_bitmap(unsigned char *bmap,
576 			       int ich, int och, int num_outs)
577 {
578 	int idx = ich * num_outs + och;
579 	return bmap[idx >> 3] & (0x80 >> (idx & 7));
580 }
581 
582 /*
583  * add an alsa control element
584  * search and increment the index until an empty slot is found.
585  *
586  * if failed, give up and free the control instance.
587  */
588 
589 int snd_usb_mixer_add_list(struct usb_mixer_elem_list *list,
590 			   struct snd_kcontrol *kctl,
591 			   bool is_std_info)
592 {
593 	struct usb_mixer_interface *mixer = list->mixer;
594 	int err;
595 
596 	while (snd_ctl_find_id(mixer->chip->card, &kctl->id))
597 		kctl->id.index++;
598 	err = snd_ctl_add(mixer->chip->card, kctl);
599 	if (err < 0) {
600 		usb_audio_dbg(mixer->chip, "cannot add control (err = %d)\n",
601 			      err);
602 		return err;
603 	}
604 	list->kctl = kctl;
605 	list->is_std_info = is_std_info;
606 	list->next_id_elem = mixer->id_elems[list->id];
607 	mixer->id_elems[list->id] = list;
608 	return 0;
609 }
610 
611 /*
612  * get a terminal name string
613  */
614 
615 static struct iterm_name_combo {
616 	int type;
617 	char *name;
618 } iterm_names[] = {
619 	{ 0x0300, "Output" },
620 	{ 0x0301, "Speaker" },
621 	{ 0x0302, "Headphone" },
622 	{ 0x0303, "HMD Audio" },
623 	{ 0x0304, "Desktop Speaker" },
624 	{ 0x0305, "Room Speaker" },
625 	{ 0x0306, "Com Speaker" },
626 	{ 0x0307, "LFE" },
627 	{ 0x0600, "External In" },
628 	{ 0x0601, "Analog In" },
629 	{ 0x0602, "Digital In" },
630 	{ 0x0603, "Line" },
631 	{ 0x0604, "Legacy In" },
632 	{ 0x0605, "IEC958 In" },
633 	{ 0x0606, "1394 DA Stream" },
634 	{ 0x0607, "1394 DV Stream" },
635 	{ 0x0700, "Embedded" },
636 	{ 0x0701, "Noise Source" },
637 	{ 0x0702, "Equalization Noise" },
638 	{ 0x0703, "CD" },
639 	{ 0x0704, "DAT" },
640 	{ 0x0705, "DCC" },
641 	{ 0x0706, "MiniDisk" },
642 	{ 0x0707, "Analog Tape" },
643 	{ 0x0708, "Phonograph" },
644 	{ 0x0709, "VCR Audio" },
645 	{ 0x070a, "Video Disk Audio" },
646 	{ 0x070b, "DVD Audio" },
647 	{ 0x070c, "TV Tuner Audio" },
648 	{ 0x070d, "Satellite Rec Audio" },
649 	{ 0x070e, "Cable Tuner Audio" },
650 	{ 0x070f, "DSS Audio" },
651 	{ 0x0710, "Radio Receiver" },
652 	{ 0x0711, "Radio Transmitter" },
653 	{ 0x0712, "Multi-Track Recorder" },
654 	{ 0x0713, "Synthesizer" },
655 	{ 0 },
656 };
657 
658 static int get_term_name(struct snd_usb_audio *chip, struct usb_audio_term *iterm,
659 			 unsigned char *name, int maxlen, int term_only)
660 {
661 	struct iterm_name_combo *names;
662 	int len;
663 
664 	if (iterm->name) {
665 		len = snd_usb_copy_string_desc(chip, iterm->name,
666 						name, maxlen);
667 		if (len)
668 			return len;
669 	}
670 
671 	/* virtual type - not a real terminal */
672 	if (iterm->type >> 16) {
673 		if (term_only)
674 			return 0;
675 		switch (iterm->type >> 16) {
676 		case UAC3_SELECTOR_UNIT:
677 			strcpy(name, "Selector");
678 			return 8;
679 		case UAC3_PROCESSING_UNIT:
680 			strcpy(name, "Process Unit");
681 			return 12;
682 		case UAC3_EXTENSION_UNIT:
683 			strcpy(name, "Ext Unit");
684 			return 8;
685 		case UAC3_MIXER_UNIT:
686 			strcpy(name, "Mixer");
687 			return 5;
688 		default:
689 			return sprintf(name, "Unit %d", iterm->id);
690 		}
691 	}
692 
693 	switch (iterm->type & 0xff00) {
694 	case 0x0100:
695 		strcpy(name, "PCM");
696 		return 3;
697 	case 0x0200:
698 		strcpy(name, "Mic");
699 		return 3;
700 	case 0x0400:
701 		strcpy(name, "Headset");
702 		return 7;
703 	case 0x0500:
704 		strcpy(name, "Phone");
705 		return 5;
706 	}
707 
708 	for (names = iterm_names; names->type; names++) {
709 		if (names->type == iterm->type) {
710 			strcpy(name, names->name);
711 			return strlen(names->name);
712 		}
713 	}
714 
715 	return 0;
716 }
717 
718 /*
719  * Get logical cluster information for UAC3 devices.
720  */
721 static int get_cluster_channels_v3(struct mixer_build *state, unsigned int cluster_id)
722 {
723 	struct uac3_cluster_header_descriptor c_header;
724 	int err;
725 
726 	err = snd_usb_ctl_msg(state->chip->dev,
727 			usb_rcvctrlpipe(state->chip->dev, 0),
728 			UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
729 			USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
730 			cluster_id,
731 			snd_usb_ctrl_intf(state->chip),
732 			&c_header, sizeof(c_header));
733 	if (err < 0)
734 		goto error;
735 	if (err != sizeof(c_header)) {
736 		err = -EIO;
737 		goto error;
738 	}
739 
740 	return c_header.bNrChannels;
741 
742 error:
743 	usb_audio_err(state->chip, "cannot request logical cluster ID: %d (err: %d)\n", cluster_id, err);
744 	return err;
745 }
746 
747 /*
748  * Get number of channels for a Mixer Unit.
749  */
750 static int uac_mixer_unit_get_channels(struct mixer_build *state,
751 				       struct uac_mixer_unit_descriptor *desc)
752 {
753 	int mu_channels;
754 
755 	switch (state->mixer->protocol) {
756 	case UAC_VERSION_1:
757 	case UAC_VERSION_2:
758 	default:
759 		if (desc->bLength < sizeof(*desc) + desc->bNrInPins + 1)
760 			return 0; /* no bmControls -> skip */
761 		mu_channels = uac_mixer_unit_bNrChannels(desc);
762 		break;
763 	case UAC_VERSION_3:
764 		mu_channels = get_cluster_channels_v3(state,
765 				uac3_mixer_unit_wClusterDescrID(desc));
766 		break;
767 	}
768 
769 	return mu_channels;
770 }
771 
772 /*
773  * Parse Input Terminal Unit
774  */
775 static int __check_input_term(struct mixer_build *state, int id,
776 			      struct usb_audio_term *term);
777 
778 static int parse_term_uac1_iterm_unit(struct mixer_build *state,
779 				      struct usb_audio_term *term,
780 				      void *p1, int id)
781 {
782 	struct uac_input_terminal_descriptor *d = p1;
783 
784 	term->type = le16_to_cpu(d->wTerminalType);
785 	term->channels = d->bNrChannels;
786 	term->chconfig = le16_to_cpu(d->wChannelConfig);
787 	term->name = d->iTerminal;
788 	return 0;
789 }
790 
791 static int parse_term_uac2_iterm_unit(struct mixer_build *state,
792 				      struct usb_audio_term *term,
793 				      void *p1, int id)
794 {
795 	struct uac2_input_terminal_descriptor *d = p1;
796 	int err;
797 
798 	/* call recursively to verify the referenced clock entity */
799 	err = __check_input_term(state, d->bCSourceID, term);
800 	if (err < 0)
801 		return err;
802 
803 	/* save input term properties after recursion,
804 	 * to ensure they are not overriden by the recursion calls
805 	 */
806 	term->id = id;
807 	term->type = le16_to_cpu(d->wTerminalType);
808 	term->channels = d->bNrChannels;
809 	term->chconfig = le32_to_cpu(d->bmChannelConfig);
810 	term->name = d->iTerminal;
811 	return 0;
812 }
813 
814 static int parse_term_uac3_iterm_unit(struct mixer_build *state,
815 				      struct usb_audio_term *term,
816 				      void *p1, int id)
817 {
818 	struct uac3_input_terminal_descriptor *d = p1;
819 	int err;
820 
821 	/* call recursively to verify the referenced clock entity */
822 	err = __check_input_term(state, d->bCSourceID, term);
823 	if (err < 0)
824 		return err;
825 
826 	/* save input term properties after recursion,
827 	 * to ensure they are not overriden by the recursion calls
828 	 */
829 	term->id = id;
830 	term->type = le16_to_cpu(d->wTerminalType);
831 
832 	err = get_cluster_channels_v3(state, le16_to_cpu(d->wClusterDescrID));
833 	if (err < 0)
834 		return err;
835 	term->channels = err;
836 
837 	/* REVISIT: UAC3 IT doesn't have channels cfg */
838 	term->chconfig = 0;
839 
840 	term->name = le16_to_cpu(d->wTerminalDescrStr);
841 	return 0;
842 }
843 
844 static int parse_term_mixer_unit(struct mixer_build *state,
845 				 struct usb_audio_term *term,
846 				 void *p1, int id)
847 {
848 	struct uac_mixer_unit_descriptor *d = p1;
849 	int protocol = state->mixer->protocol;
850 	int err;
851 
852 	err = uac_mixer_unit_get_channels(state, d);
853 	if (err <= 0)
854 		return err;
855 
856 	term->type = UAC3_MIXER_UNIT << 16; /* virtual type */
857 	term->channels = err;
858 	if (protocol != UAC_VERSION_3) {
859 		term->chconfig = uac_mixer_unit_wChannelConfig(d, protocol);
860 		term->name = uac_mixer_unit_iMixer(d);
861 	}
862 	return 0;
863 }
864 
865 static int parse_term_selector_unit(struct mixer_build *state,
866 				    struct usb_audio_term *term,
867 				    void *p1, int id)
868 {
869 	struct uac_selector_unit_descriptor *d = p1;
870 	int err;
871 
872 	/* call recursively to retrieve the channel info */
873 	err = __check_input_term(state, d->baSourceID[0], term);
874 	if (err < 0)
875 		return err;
876 	term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */
877 	term->id = id;
878 	if (state->mixer->protocol != UAC_VERSION_3)
879 		term->name = uac_selector_unit_iSelector(d);
880 	return 0;
881 }
882 
883 static int parse_term_proc_unit(struct mixer_build *state,
884 				struct usb_audio_term *term,
885 				void *p1, int id, int vtype)
886 {
887 	struct uac_processing_unit_descriptor *d = p1;
888 	int protocol = state->mixer->protocol;
889 	int err;
890 
891 	if (d->bNrInPins) {
892 		/* call recursively to retrieve the channel info */
893 		err = __check_input_term(state, d->baSourceID[0], term);
894 		if (err < 0)
895 			return err;
896 	}
897 
898 	term->type = vtype << 16; /* virtual type */
899 	term->id = id;
900 
901 	if (protocol == UAC_VERSION_3)
902 		return 0;
903 
904 	if (!term->channels) {
905 		term->channels = uac_processing_unit_bNrChannels(d);
906 		term->chconfig = uac_processing_unit_wChannelConfig(d, protocol);
907 	}
908 	term->name = uac_processing_unit_iProcessing(d, protocol);
909 	return 0;
910 }
911 
912 static int parse_term_effect_unit(struct mixer_build *state,
913 				  struct usb_audio_term *term,
914 				  void *p1, int id)
915 {
916 	struct uac2_effect_unit_descriptor *d = p1;
917 	int err;
918 
919 	err = __check_input_term(state, d->bSourceID, term);
920 	if (err < 0)
921 		return err;
922 	term->type = UAC3_EFFECT_UNIT << 16; /* virtual type */
923 	term->id = id;
924 	return 0;
925 }
926 
927 static int parse_term_uac2_clock_source(struct mixer_build *state,
928 					struct usb_audio_term *term,
929 					void *p1, int id)
930 {
931 	struct uac_clock_source_descriptor *d = p1;
932 
933 	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
934 	term->id = id;
935 	term->name = d->iClockSource;
936 	return 0;
937 }
938 
939 static int parse_term_uac3_clock_source(struct mixer_build *state,
940 					struct usb_audio_term *term,
941 					void *p1, int id)
942 {
943 	struct uac3_clock_source_descriptor *d = p1;
944 
945 	term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
946 	term->id = id;
947 	term->name = le16_to_cpu(d->wClockSourceStr);
948 	return 0;
949 }
950 
951 #define PTYPE(a, b)	((a) << 8 | (b))
952 
953 /*
954  * parse the source unit recursively until it reaches to a terminal
955  * or a branched unit.
956  */
957 static int __check_input_term(struct mixer_build *state, int id,
958 			      struct usb_audio_term *term)
959 {
960 	int protocol = state->mixer->protocol;
961 	void *p1;
962 	unsigned char *hdr;
963 
964 	for (;;) {
965 		/* a loop in the terminal chain? */
966 		if (test_and_set_bit(id, state->termbitmap))
967 			return -EINVAL;
968 
969 		p1 = find_audio_control_unit(state, id);
970 		if (!p1)
971 			break;
972 		if (!snd_usb_validate_audio_desc(p1, protocol))
973 			break; /* bad descriptor */
974 
975 		hdr = p1;
976 		term->id = id;
977 
978 		switch (PTYPE(protocol, hdr[2])) {
979 		case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):
980 		case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):
981 		case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT): {
982 			/* the header is the same for all versions */
983 			struct uac_feature_unit_descriptor *d = p1;
984 
985 			id = d->bSourceID;
986 			break; /* continue to parse */
987 		}
988 		case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):
989 			return parse_term_uac1_iterm_unit(state, term, p1, id);
990 		case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):
991 			return parse_term_uac2_iterm_unit(state, term, p1, id);
992 		case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):
993 			return parse_term_uac3_iterm_unit(state, term, p1, id);
994 		case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):
995 		case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):
996 		case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):
997 			return parse_term_mixer_unit(state, term, p1, id);
998 		case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):
999 		case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):
1000 		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):
1001 		case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):
1002 		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):
1003 			return parse_term_selector_unit(state, term, p1, id);
1004 		case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):
1005 		case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):
1006 		case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):
1007 			return parse_term_proc_unit(state, term, p1, id,
1008 						    UAC3_PROCESSING_UNIT);
1009 		case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):
1010 		case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):
1011 			return parse_term_effect_unit(state, term, p1, id);
1012 		case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):
1013 		case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):
1014 		case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):
1015 			return parse_term_proc_unit(state, term, p1, id,
1016 						    UAC3_EXTENSION_UNIT);
1017 		case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):
1018 			return parse_term_uac2_clock_source(state, term, p1, id);
1019 		case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):
1020 			return parse_term_uac3_clock_source(state, term, p1, id);
1021 		default:
1022 			return -ENODEV;
1023 		}
1024 	}
1025 	return -ENODEV;
1026 }
1027 
1028 
1029 static int check_input_term(struct mixer_build *state, int id,
1030 			    struct usb_audio_term *term)
1031 {
1032 	memset(term, 0, sizeof(*term));
1033 	memset(state->termbitmap, 0, sizeof(state->termbitmap));
1034 	return __check_input_term(state, id, term);
1035 }
1036 
1037 /*
1038  * Feature Unit
1039  */
1040 
1041 /* feature unit control information */
1042 struct usb_feature_control_info {
1043 	int control;
1044 	const char *name;
1045 	int type;	/* data type for uac1 */
1046 	int type_uac2;	/* data type for uac2 if different from uac1, else -1 */
1047 };
1048 
1049 static const struct usb_feature_control_info audio_feature_info[] = {
1050 	{ UAC_FU_MUTE,			"Mute",			USB_MIXER_INV_BOOLEAN, -1 },
1051 	{ UAC_FU_VOLUME,		"Volume",		USB_MIXER_S16, -1 },
1052 	{ UAC_FU_BASS,			"Tone Control - Bass",	USB_MIXER_S8, -1 },
1053 	{ UAC_FU_MID,			"Tone Control - Mid",	USB_MIXER_S8, -1 },
1054 	{ UAC_FU_TREBLE,		"Tone Control - Treble", USB_MIXER_S8, -1 },
1055 	{ UAC_FU_GRAPHIC_EQUALIZER,	"Graphic Equalizer",	USB_MIXER_S8, -1 }, /* FIXME: not implemented yet */
1056 	{ UAC_FU_AUTOMATIC_GAIN,	"Auto Gain Control",	USB_MIXER_BOOLEAN, -1 },
1057 	{ UAC_FU_DELAY,			"Delay Control",	USB_MIXER_U16, USB_MIXER_U32 },
1058 	{ UAC_FU_BASS_BOOST,		"Bass Boost",		USB_MIXER_BOOLEAN, -1 },
1059 	{ UAC_FU_LOUDNESS,		"Loudness",		USB_MIXER_BOOLEAN, -1 },
1060 	/* UAC2 specific */
1061 	{ UAC2_FU_INPUT_GAIN,		"Input Gain Control",	USB_MIXER_S16, -1 },
1062 	{ UAC2_FU_INPUT_GAIN_PAD,	"Input Gain Pad Control", USB_MIXER_S16, -1 },
1063 	{ UAC2_FU_PHASE_INVERTER,	 "Phase Inverter Control", USB_MIXER_BOOLEAN, -1 },
1064 };
1065 
1066 static void usb_mixer_elem_info_free(struct usb_mixer_elem_info *cval)
1067 {
1068 	kfree(cval);
1069 }
1070 
1071 /* private_free callback */
1072 void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
1073 {
1074 	usb_mixer_elem_info_free(kctl->private_data);
1075 	kctl->private_data = NULL;
1076 }
1077 
1078 /*
1079  * interface to ALSA control for feature/mixer units
1080  */
1081 
1082 /* volume control quirks */
1083 static void volume_control_quirks(struct usb_mixer_elem_info *cval,
1084 				  struct snd_kcontrol *kctl)
1085 {
1086 	struct snd_usb_audio *chip = cval->head.mixer->chip;
1087 	switch (chip->usb_id) {
1088 	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
1089 	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
1090 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
1091 			cval->min = 0x0000;
1092 			cval->max = 0xffff;
1093 			cval->res = 0x00e6;
1094 			break;
1095 		}
1096 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1097 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1098 			cval->min = 0x00;
1099 			cval->max = 0xff;
1100 			break;
1101 		}
1102 		if (strstr(kctl->id.name, "Effect Return") != NULL) {
1103 			cval->min = 0xb706;
1104 			cval->max = 0xff7b;
1105 			cval->res = 0x0073;
1106 			break;
1107 		}
1108 		if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
1109 			(strstr(kctl->id.name, "Effect Send") != NULL)) {
1110 			cval->min = 0xb5fb; /* -73 dB = 0xb6ff */
1111 			cval->max = 0xfcfe;
1112 			cval->res = 0x0073;
1113 		}
1114 		break;
1115 
1116 	case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */
1117 	case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
1118 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
1119 			usb_audio_info(chip,
1120 				       "set quirk for FTU Effect Duration\n");
1121 			cval->min = 0x0000;
1122 			cval->max = 0x7f00;
1123 			cval->res = 0x0100;
1124 			break;
1125 		}
1126 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1127 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1128 			usb_audio_info(chip,
1129 				       "set quirks for FTU Effect Feedback/Volume\n");
1130 			cval->min = 0x00;
1131 			cval->max = 0x7f;
1132 			break;
1133 		}
1134 		break;
1135 
1136 	case USB_ID(0x0d8c, 0x0103):
1137 		if (!strcmp(kctl->id.name, "PCM Playback Volume")) {
1138 			usb_audio_info(chip,
1139 				 "set volume quirk for CM102-A+/102S+\n");
1140 			cval->min = -256;
1141 		}
1142 		break;
1143 
1144 	case USB_ID(0x0471, 0x0101):
1145 	case USB_ID(0x0471, 0x0104):
1146 	case USB_ID(0x0471, 0x0105):
1147 	case USB_ID(0x0672, 0x1041):
1148 	/* quirk for UDA1321/N101.
1149 	 * note that detection between firmware 2.1.1.7 (N101)
1150 	 * and later 2.1.1.21 is not very clear from datasheets.
1151 	 * I hope that the min value is -15360 for newer firmware --jk
1152 	 */
1153 		if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
1154 		    cval->min == -15616) {
1155 			usb_audio_info(chip,
1156 				 "set volume quirk for UDA1321/N101 chip\n");
1157 			cval->max = -256;
1158 		}
1159 		break;
1160 
1161 	case USB_ID(0x046d, 0x09a4):
1162 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1163 			usb_audio_info(chip,
1164 				"set volume quirk for QuickCam E3500\n");
1165 			cval->min = 6080;
1166 			cval->max = 8768;
1167 			cval->res = 192;
1168 		}
1169 		break;
1170 
1171 	case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
1172 	case USB_ID(0x046d, 0x0808):
1173 	case USB_ID(0x046d, 0x0809):
1174 	case USB_ID(0x046d, 0x0819): /* Logitech Webcam C210 */
1175 	case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
1176 	case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
1177 	case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
1178 	case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
1179 	case USB_ID(0x046d, 0x08ca): /* Logitech Quickcam Fusion */
1180 	case USB_ID(0x046d, 0x0991):
1181 	case USB_ID(0x046d, 0x09a2): /* QuickCam Communicate Deluxe/S7500 */
1182 	/* Most audio usb devices lie about volume resolution.
1183 	 * Most Logitech webcams have res = 384.
1184 	 * Probably there is some logitech magic behind this number --fishor
1185 	 */
1186 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1187 			usb_audio_info(chip,
1188 				"set resolution quirk: cval->res = 384\n");
1189 			cval->res = 384;
1190 		}
1191 		break;
1192 	case USB_ID(0x0495, 0x3042): /* ESS Technology Asus USB DAC */
1193 		if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
1194 			strstr(kctl->id.name, "Capture Volume") != NULL) {
1195 			cval->min >>= 8;
1196 			cval->max = 0;
1197 			cval->res = 1;
1198 		}
1199 		break;
1200 	case USB_ID(0x1224, 0x2a25): /* Jieli Technology USB PHY 2.0 */
1201 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1202 			usb_audio_info(chip,
1203 				"set resolution quirk: cval->res = 16\n");
1204 			cval->res = 16;
1205 		}
1206 		break;
1207 	}
1208 }
1209 
1210 /* forcibly initialize the current mixer value; if GET_CUR fails, set to
1211  * the minimum as default
1212  */
1213 static void init_cur_mix_raw(struct usb_mixer_elem_info *cval, int ch, int idx)
1214 {
1215 	int val, err;
1216 
1217 	err = snd_usb_get_cur_mix_value(cval, ch, idx, &val);
1218 	if (!err)
1219 		return;
1220 	if (!cval->head.mixer->ignore_ctl_error)
1221 		usb_audio_warn(cval->head.mixer->chip,
1222 			       "%d:%d: failed to get current value for ch %d (%d)\n",
1223 			       cval->head.id, mixer_ctrl_intf(cval->head.mixer),
1224 			       ch, err);
1225 	snd_usb_set_cur_mix_value(cval, ch, idx, cval->min);
1226 }
1227 
1228 /*
1229  * retrieve the minimum and maximum values for the specified control
1230  */
1231 static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
1232 				   int default_min, struct snd_kcontrol *kctl)
1233 {
1234 	int i, idx;
1235 
1236 	/* for failsafe */
1237 	cval->min = default_min;
1238 	cval->max = cval->min + 1;
1239 	cval->res = 1;
1240 	cval->dBmin = cval->dBmax = 0;
1241 
1242 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1243 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1244 		cval->initialized = 1;
1245 	} else {
1246 		int minchn = 0;
1247 		if (cval->cmask) {
1248 			for (i = 0; i < MAX_CHANNELS; i++)
1249 				if (cval->cmask & (1 << i)) {
1250 					minchn = i + 1;
1251 					break;
1252 				}
1253 		}
1254 		if (get_ctl_value(cval, UAC_GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
1255 		    get_ctl_value(cval, UAC_GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
1256 			usb_audio_err(cval->head.mixer->chip,
1257 				      "%d:%d: cannot get min/max values for control %d (id %d)\n",
1258 				   cval->head.id, mixer_ctrl_intf(cval->head.mixer),
1259 							       cval->control, cval->head.id);
1260 			return -EINVAL;
1261 		}
1262 		if (get_ctl_value(cval, UAC_GET_RES,
1263 				  (cval->control << 8) | minchn,
1264 				  &cval->res) < 0) {
1265 			cval->res = 1;
1266 		} else if (cval->head.mixer->protocol == UAC_VERSION_1) {
1267 			int last_valid_res = cval->res;
1268 
1269 			while (cval->res > 1) {
1270 				if (snd_usb_mixer_set_ctl_value(cval, UAC_SET_RES,
1271 								(cval->control << 8) | minchn,
1272 								cval->res / 2) < 0)
1273 					break;
1274 				cval->res /= 2;
1275 			}
1276 			if (get_ctl_value(cval, UAC_GET_RES,
1277 					  (cval->control << 8) | minchn, &cval->res) < 0)
1278 				cval->res = last_valid_res;
1279 		}
1280 		if (cval->res == 0)
1281 			cval->res = 1;
1282 
1283 		/* Additional checks for the proper resolution
1284 		 *
1285 		 * Some devices report smaller resolutions than actually
1286 		 * reacting.  They don't return errors but simply clip
1287 		 * to the lower aligned value.
1288 		 */
1289 		if (cval->min + cval->res < cval->max) {
1290 			int last_valid_res = cval->res;
1291 			int saved, test, check;
1292 			if (get_cur_mix_raw(cval, minchn, &saved) < 0)
1293 				goto no_res_check;
1294 			for (;;) {
1295 				test = saved;
1296 				if (test < cval->max)
1297 					test += cval->res;
1298 				else
1299 					test -= cval->res;
1300 				if (test < cval->min || test > cval->max ||
1301 				    snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||
1302 				    get_cur_mix_raw(cval, minchn, &check)) {
1303 					cval->res = last_valid_res;
1304 					break;
1305 				}
1306 				if (test == check)
1307 					break;
1308 				cval->res *= 2;
1309 			}
1310 			snd_usb_set_cur_mix_value(cval, minchn, 0, saved);
1311 		}
1312 
1313 no_res_check:
1314 		cval->initialized = 1;
1315 	}
1316 
1317 	if (kctl)
1318 		volume_control_quirks(cval, kctl);
1319 
1320 	/* USB descriptions contain the dB scale in 1/256 dB unit
1321 	 * while ALSA TLV contains in 1/100 dB unit
1322 	 */
1323 	cval->dBmin = (convert_signed_value(cval, cval->min) * 100) / 256;
1324 	cval->dBmax = (convert_signed_value(cval, cval->max) * 100) / 256;
1325 	if (cval->dBmin > cval->dBmax) {
1326 		/* something is wrong; assume it's either from/to 0dB */
1327 		if (cval->dBmin < 0)
1328 			cval->dBmax = 0;
1329 		else if (cval->dBmin > 0)
1330 			cval->dBmin = 0;
1331 		if (cval->dBmin > cval->dBmax) {
1332 			/* totally crap, return an error */
1333 			return -EINVAL;
1334 		}
1335 	} else {
1336 		/* if the max volume is too low, it's likely a bogus range;
1337 		 * here we use -96dB as the threshold
1338 		 */
1339 		if (cval->dBmax <= -9600) {
1340 			usb_audio_info(cval->head.mixer->chip,
1341 				       "%d:%d: bogus dB values (%d/%d), disabling dB reporting\n",
1342 				       cval->head.id, mixer_ctrl_intf(cval->head.mixer),
1343 				       cval->dBmin, cval->dBmax);
1344 			cval->dBmin = cval->dBmax = 0;
1345 		}
1346 	}
1347 
1348 	/* initialize all elements */
1349 	if (!cval->cmask) {
1350 		init_cur_mix_raw(cval, 0, 0);
1351 	} else {
1352 		idx = 0;
1353 		for (i = 0; i < MAX_CHANNELS; i++) {
1354 			if (cval->cmask & (1 << i)) {
1355 				init_cur_mix_raw(cval, i + 1, idx);
1356 				idx++;
1357 			}
1358 		}
1359 	}
1360 
1361 	return 0;
1362 }
1363 
1364 #define get_min_max(cval, def)	get_min_max_with_quirks(cval, def, NULL)
1365 
1366 /* get a feature/mixer unit info */
1367 static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol,
1368 				  struct snd_ctl_elem_info *uinfo)
1369 {
1370 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1371 
1372 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1373 	    cval->val_type == USB_MIXER_INV_BOOLEAN)
1374 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1375 	else
1376 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1377 	uinfo->count = cval->channels;
1378 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1379 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1380 		uinfo->value.integer.min = 0;
1381 		uinfo->value.integer.max = 1;
1382 	} else {
1383 		if (!cval->initialized) {
1384 			get_min_max_with_quirks(cval, 0, kcontrol);
1385 			if (cval->initialized && cval->dBmin >= cval->dBmax) {
1386 				kcontrol->vd[0].access &=
1387 					~(SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1388 					  SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
1389 				snd_ctl_notify(cval->head.mixer->chip->card,
1390 					       SNDRV_CTL_EVENT_MASK_INFO,
1391 					       &kcontrol->id);
1392 			}
1393 		}
1394 		uinfo->value.integer.min = 0;
1395 		uinfo->value.integer.max =
1396 			DIV_ROUND_UP(cval->max - cval->min, cval->res);
1397 	}
1398 	return 0;
1399 }
1400 
1401 /* get the current value from feature/mixer unit */
1402 static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol,
1403 				 struct snd_ctl_elem_value *ucontrol)
1404 {
1405 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1406 	int c, cnt, val, err;
1407 
1408 	ucontrol->value.integer.value[0] = cval->min;
1409 	if (cval->cmask) {
1410 		cnt = 0;
1411 		for (c = 0; c < MAX_CHANNELS; c++) {
1412 			if (!(cval->cmask & (1 << c)))
1413 				continue;
1414 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &val);
1415 			if (err < 0)
1416 				return filter_error(cval, err);
1417 			val = get_relative_value(cval, val);
1418 			ucontrol->value.integer.value[cnt] = val;
1419 			cnt++;
1420 		}
1421 		return 0;
1422 	} else {
1423 		/* master channel */
1424 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1425 		if (err < 0)
1426 			return filter_error(cval, err);
1427 		val = get_relative_value(cval, val);
1428 		ucontrol->value.integer.value[0] = val;
1429 	}
1430 	return 0;
1431 }
1432 
1433 /* put the current value to feature/mixer unit */
1434 static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol,
1435 				 struct snd_ctl_elem_value *ucontrol)
1436 {
1437 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1438 	int c, cnt, val, oval, err;
1439 	int changed = 0;
1440 
1441 	if (cval->cmask) {
1442 		cnt = 0;
1443 		for (c = 0; c < MAX_CHANNELS; c++) {
1444 			if (!(cval->cmask & (1 << c)))
1445 				continue;
1446 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &oval);
1447 			if (err < 0)
1448 				return filter_error(cval, err);
1449 			val = ucontrol->value.integer.value[cnt];
1450 			val = get_abs_value(cval, val);
1451 			if (oval != val) {
1452 				snd_usb_set_cur_mix_value(cval, c + 1, cnt, val);
1453 				changed = 1;
1454 			}
1455 			cnt++;
1456 		}
1457 	} else {
1458 		/* master channel */
1459 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &oval);
1460 		if (err < 0)
1461 			return filter_error(cval, err);
1462 		val = ucontrol->value.integer.value[0];
1463 		val = get_abs_value(cval, val);
1464 		if (val != oval) {
1465 			snd_usb_set_cur_mix_value(cval, 0, 0, val);
1466 			changed = 1;
1467 		}
1468 	}
1469 	return changed;
1470 }
1471 
1472 /* get the boolean value from the master channel of a UAC control */
1473 static int mixer_ctl_master_bool_get(struct snd_kcontrol *kcontrol,
1474 				     struct snd_ctl_elem_value *ucontrol)
1475 {
1476 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1477 	int val, err;
1478 
1479 	err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1480 	if (err < 0)
1481 		return filter_error(cval, err);
1482 	val = (val != 0);
1483 	ucontrol->value.integer.value[0] = val;
1484 	return 0;
1485 }
1486 
1487 static int get_connector_value(struct usb_mixer_elem_info *cval,
1488 			       char *name, int *val)
1489 {
1490 	struct snd_usb_audio *chip = cval->head.mixer->chip;
1491 	int idx = 0, validx, ret;
1492 
1493 	validx = cval->control << 8 | 0;
1494 
1495 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
1496 	if (ret)
1497 		goto error;
1498 
1499 	idx = mixer_ctrl_intf(cval->head.mixer) | (cval->head.id << 8);
1500 	if (cval->head.mixer->protocol == UAC_VERSION_2) {
1501 		struct uac2_connectors_ctl_blk uac2_conn;
1502 
1503 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1504 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1505 				      validx, idx, &uac2_conn, sizeof(uac2_conn));
1506 		if (val)
1507 			*val = !!uac2_conn.bNrChannels;
1508 	} else { /* UAC_VERSION_3 */
1509 		struct uac3_insertion_ctl_blk uac3_conn;
1510 
1511 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1512 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1513 				      validx, idx, &uac3_conn, sizeof(uac3_conn));
1514 		if (val)
1515 			*val = !!uac3_conn.bmConInserted;
1516 	}
1517 
1518 	snd_usb_unlock_shutdown(chip);
1519 
1520 	if (ret < 0) {
1521 		if (name && strstr(name, "Speaker")) {
1522 			if (val)
1523 				*val = 1;
1524 			return 0;
1525 		}
1526 error:
1527 		usb_audio_err(chip,
1528 			"cannot get connectors status: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
1529 			UAC_GET_CUR, validx, idx, cval->val_type);
1530 
1531 		if (val)
1532 			*val = 0;
1533 
1534 		return filter_error(cval, ret);
1535 	}
1536 
1537 	return ret;
1538 }
1539 
1540 /* get the connectors status and report it as boolean type */
1541 static int mixer_ctl_connector_get(struct snd_kcontrol *kcontrol,
1542 				   struct snd_ctl_elem_value *ucontrol)
1543 {
1544 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1545 	int ret, val;
1546 
1547 	ret = get_connector_value(cval, kcontrol->id.name, &val);
1548 
1549 	if (ret < 0)
1550 		return ret;
1551 
1552 	ucontrol->value.integer.value[0] = val;
1553 	return 0;
1554 }
1555 
1556 static const struct snd_kcontrol_new usb_feature_unit_ctl = {
1557 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1558 	.name = "", /* will be filled later manually */
1559 	.info = mixer_ctl_feature_info,
1560 	.get = mixer_ctl_feature_get,
1561 	.put = mixer_ctl_feature_put,
1562 };
1563 
1564 /* the read-only variant */
1565 static const struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
1566 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1567 	.name = "", /* will be filled later manually */
1568 	.info = mixer_ctl_feature_info,
1569 	.get = mixer_ctl_feature_get,
1570 	.put = NULL,
1571 };
1572 
1573 /*
1574  * A control which shows the boolean value from reading a UAC control on
1575  * the master channel.
1576  */
1577 static const struct snd_kcontrol_new usb_bool_master_control_ctl_ro = {
1578 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1579 	.name = "", /* will be filled later manually */
1580 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1581 	.info = snd_ctl_boolean_mono_info,
1582 	.get = mixer_ctl_master_bool_get,
1583 	.put = NULL,
1584 };
1585 
1586 static const struct snd_kcontrol_new usb_connector_ctl_ro = {
1587 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1588 	.name = "", /* will be filled later manually */
1589 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1590 	.info = snd_ctl_boolean_mono_info,
1591 	.get = mixer_ctl_connector_get,
1592 	.put = NULL,
1593 };
1594 
1595 /*
1596  * This symbol is exported in order to allow the mixer quirks to
1597  * hook up to the standard feature unit control mechanism
1598  */
1599 const struct snd_kcontrol_new *snd_usb_feature_unit_ctl = &usb_feature_unit_ctl;
1600 
1601 /*
1602  * build a feature control
1603  */
1604 static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
1605 {
1606 	return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
1607 }
1608 
1609 /*
1610  * A lot of headsets/headphones have a "Speaker" mixer. Make sure we
1611  * rename it to "Headphone". We determine if something is a headphone
1612  * similar to how udev determines form factor.
1613  */
1614 static void check_no_speaker_on_headset(struct snd_kcontrol *kctl,
1615 					struct snd_card *card)
1616 {
1617 	static const char * const names_to_check[] = {
1618 		"Headset", "headset", "Headphone", "headphone", NULL};
1619 	const char * const *s;
1620 	bool found = false;
1621 
1622 	if (strcmp("Speaker", kctl->id.name))
1623 		return;
1624 
1625 	for (s = names_to_check; *s; s++)
1626 		if (strstr(card->shortname, *s)) {
1627 			found = true;
1628 			break;
1629 		}
1630 
1631 	if (!found)
1632 		return;
1633 
1634 	snd_ctl_rename(card, kctl, "Headphone");
1635 }
1636 
1637 static const struct usb_feature_control_info *get_feature_control_info(int control)
1638 {
1639 	int i;
1640 
1641 	for (i = 0; i < ARRAY_SIZE(audio_feature_info); ++i) {
1642 		if (audio_feature_info[i].control == control)
1643 			return &audio_feature_info[i];
1644 	}
1645 	return NULL;
1646 }
1647 
1648 static void __build_feature_ctl(struct usb_mixer_interface *mixer,
1649 				const struct usbmix_name_map *imap,
1650 				unsigned int ctl_mask, int control,
1651 				struct usb_audio_term *iterm,
1652 				struct usb_audio_term *oterm,
1653 				int unitid, int nameid, int readonly_mask)
1654 {
1655 	const struct usb_feature_control_info *ctl_info;
1656 	unsigned int len = 0;
1657 	int mapped_name = 0;
1658 	struct snd_kcontrol *kctl;
1659 	struct usb_mixer_elem_info *cval;
1660 	const struct usbmix_name_map *map;
1661 	unsigned int range;
1662 
1663 	if (control == UAC_FU_GRAPHIC_EQUALIZER) {
1664 		/* FIXME: not supported yet */
1665 		return;
1666 	}
1667 
1668 	map = find_map(imap, unitid, control);
1669 	if (check_ignored_ctl(map))
1670 		return;
1671 
1672 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1673 	if (!cval)
1674 		return;
1675 	snd_usb_mixer_elem_init_std(&cval->head, mixer, unitid);
1676 	cval->control = control;
1677 	cval->cmask = ctl_mask;
1678 
1679 	ctl_info = get_feature_control_info(control);
1680 	if (!ctl_info) {
1681 		usb_mixer_elem_info_free(cval);
1682 		return;
1683 	}
1684 	if (mixer->protocol == UAC_VERSION_1)
1685 		cval->val_type = ctl_info->type;
1686 	else /* UAC_VERSION_2 */
1687 		cval->val_type = ctl_info->type_uac2 >= 0 ?
1688 			ctl_info->type_uac2 : ctl_info->type;
1689 
1690 	if (ctl_mask == 0) {
1691 		cval->channels = 1;	/* master channel */
1692 		cval->master_readonly = readonly_mask;
1693 	} else {
1694 		int i, c = 0;
1695 		for (i = 0; i < 16; i++)
1696 			if (ctl_mask & (1 << i))
1697 				c++;
1698 		cval->channels = c;
1699 		cval->ch_readonly = readonly_mask;
1700 	}
1701 
1702 	/*
1703 	 * If all channels in the mask are marked read-only, make the control
1704 	 * read-only. snd_usb_set_cur_mix_value() will check the mask again and won't
1705 	 * issue write commands to read-only channels.
1706 	 */
1707 	if (cval->channels == readonly_mask)
1708 		kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
1709 	else
1710 		kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1711 
1712 	if (!kctl) {
1713 		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
1714 		usb_mixer_elem_info_free(cval);
1715 		return;
1716 	}
1717 	kctl->private_free = snd_usb_mixer_elem_free;
1718 
1719 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1720 	mapped_name = len != 0;
1721 	if (!len && nameid)
1722 		len = snd_usb_copy_string_desc(mixer->chip, nameid,
1723 				kctl->id.name, sizeof(kctl->id.name));
1724 
1725 	switch (control) {
1726 	case UAC_FU_MUTE:
1727 	case UAC_FU_VOLUME:
1728 		/*
1729 		 * determine the control name.  the rule is:
1730 		 * - if a name id is given in descriptor, use it.
1731 		 * - if the connected input can be determined, then use the name
1732 		 *   of terminal type.
1733 		 * - if the connected output can be determined, use it.
1734 		 * - otherwise, anonymous name.
1735 		 */
1736 		if (!len) {
1737 			if (iterm)
1738 				len = get_term_name(mixer->chip, iterm,
1739 						    kctl->id.name,
1740 						    sizeof(kctl->id.name), 1);
1741 			if (!len && oterm)
1742 				len = get_term_name(mixer->chip, oterm,
1743 						    kctl->id.name,
1744 						    sizeof(kctl->id.name), 1);
1745 			if (!len)
1746 				snprintf(kctl->id.name, sizeof(kctl->id.name),
1747 					 "Feature %d", unitid);
1748 		}
1749 
1750 		if (!mapped_name)
1751 			check_no_speaker_on_headset(kctl, mixer->chip->card);
1752 
1753 		/*
1754 		 * determine the stream direction:
1755 		 * if the connected output is USB stream, then it's likely a
1756 		 * capture stream.  otherwise it should be playback (hopefully :)
1757 		 */
1758 		if (!mapped_name && oterm && !(oterm->type >> 16)) {
1759 			if ((oterm->type & 0xff00) == 0x0100)
1760 				append_ctl_name(kctl, " Capture");
1761 			else
1762 				append_ctl_name(kctl, " Playback");
1763 		}
1764 		append_ctl_name(kctl, control == UAC_FU_MUTE ?
1765 				" Switch" : " Volume");
1766 		break;
1767 	default:
1768 		if (!len)
1769 			strscpy(kctl->id.name, audio_feature_info[control-1].name,
1770 				sizeof(kctl->id.name));
1771 		break;
1772 	}
1773 
1774 	/* get min/max values */
1775 	get_min_max_with_quirks(cval, 0, kctl);
1776 
1777 	/* skip a bogus volume range */
1778 	if (cval->max <= cval->min) {
1779 		usb_audio_dbg(mixer->chip,
1780 			      "[%d] FU [%s] skipped due to invalid volume\n",
1781 			      cval->head.id, kctl->id.name);
1782 		snd_ctl_free_one(kctl);
1783 		return;
1784 	}
1785 
1786 
1787 	if (control == UAC_FU_VOLUME) {
1788 		check_mapped_dB(map, cval);
1789 		if (cval->dBmin < cval->dBmax || !cval->initialized) {
1790 			kctl->tlv.c = snd_usb_mixer_vol_tlv;
1791 			kctl->vd[0].access |=
1792 				SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1793 				SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1794 		}
1795 	}
1796 
1797 	snd_usb_mixer_fu_apply_quirk(mixer, cval, unitid, kctl);
1798 
1799 	range = (cval->max - cval->min) / cval->res;
1800 	/*
1801 	 * Are there devices with volume range more than 255? I use a bit more
1802 	 * to be sure. 384 is a resolution magic number found on Logitech
1803 	 * devices. It will definitively catch all buggy Logitech devices.
1804 	 */
1805 	if (range > 384) {
1806 		usb_audio_warn(mixer->chip,
1807 			       "Warning! Unlikely big volume range (=%u), cval->res is probably wrong.",
1808 			       range);
1809 		usb_audio_warn(mixer->chip,
1810 			       "[%d] FU [%s] ch = %d, val = %d/%d/%d",
1811 			       cval->head.id, kctl->id.name, cval->channels,
1812 			       cval->min, cval->max, cval->res);
1813 	}
1814 
1815 	usb_audio_dbg(mixer->chip, "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
1816 		      cval->head.id, kctl->id.name, cval->channels,
1817 		      cval->min, cval->max, cval->res);
1818 	snd_usb_mixer_add_control(&cval->head, kctl);
1819 }
1820 
1821 static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
1822 			      unsigned int ctl_mask, int control,
1823 			      struct usb_audio_term *iterm, int unitid,
1824 			      int readonly_mask)
1825 {
1826 	struct uac_feature_unit_descriptor *desc = raw_desc;
1827 	int nameid = uac_feature_unit_iFeature(desc);
1828 
1829 	__build_feature_ctl(state->mixer, state->map, ctl_mask, control,
1830 			iterm, &state->oterm, unitid, nameid, readonly_mask);
1831 }
1832 
1833 static void build_feature_ctl_badd(struct usb_mixer_interface *mixer,
1834 			      unsigned int ctl_mask, int control, int unitid,
1835 			      const struct usbmix_name_map *badd_map)
1836 {
1837 	__build_feature_ctl(mixer, badd_map, ctl_mask, control,
1838 			NULL, NULL, unitid, 0, 0);
1839 }
1840 
1841 static void get_connector_control_name(struct usb_mixer_interface *mixer,
1842 				       struct usb_audio_term *term,
1843 				       bool is_input, char *name, int name_size)
1844 {
1845 	int name_len = get_term_name(mixer->chip, term, name, name_size, 0);
1846 
1847 	if (name_len == 0)
1848 		strscpy(name, "Unknown", name_size);
1849 
1850 	/*
1851 	 *  sound/core/ctljack.c has a convention of naming jack controls
1852 	 * by ending in " Jack".  Make it slightly more useful by
1853 	 * indicating Input or Output after the terminal name.
1854 	 */
1855 	if (is_input)
1856 		strlcat(name, " - Input Jack", name_size);
1857 	else
1858 		strlcat(name, " - Output Jack", name_size);
1859 }
1860 
1861 /* get connector value to "wake up" the USB audio */
1862 static int connector_mixer_resume(struct usb_mixer_elem_list *list)
1863 {
1864 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
1865 
1866 	get_connector_value(cval, NULL, NULL);
1867 	return 0;
1868 }
1869 
1870 /* Build a mixer control for a UAC connector control (jack-detect) */
1871 static void build_connector_control(struct usb_mixer_interface *mixer,
1872 				    const struct usbmix_name_map *imap,
1873 				    struct usb_audio_term *term, bool is_input)
1874 {
1875 	struct snd_kcontrol *kctl;
1876 	struct usb_mixer_elem_info *cval;
1877 	const struct usbmix_name_map *map;
1878 
1879 	map = find_map(imap, term->id, 0);
1880 	if (check_ignored_ctl(map))
1881 		return;
1882 
1883 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1884 	if (!cval)
1885 		return;
1886 	snd_usb_mixer_elem_init_std(&cval->head, mixer, term->id);
1887 
1888 	/* set up a specific resume callback */
1889 	cval->head.resume = connector_mixer_resume;
1890 
1891 	/*
1892 	 * UAC2: The first byte from reading the UAC2_TE_CONNECTOR control returns the
1893 	 * number of channels connected.
1894 	 *
1895 	 * UAC3: The first byte specifies size of bitmap for the inserted controls. The
1896 	 * following byte(s) specifies which connectors are inserted.
1897 	 *
1898 	 * This boolean ctl will simply report if any channels are connected
1899 	 * or not.
1900 	 */
1901 	if (mixer->protocol == UAC_VERSION_2)
1902 		cval->control = UAC2_TE_CONNECTOR;
1903 	else /* UAC_VERSION_3 */
1904 		cval->control = UAC3_TE_INSERTION;
1905 
1906 	cval->val_type = USB_MIXER_BOOLEAN;
1907 	cval->channels = 1; /* report true if any channel is connected */
1908 	cval->min = 0;
1909 	cval->max = 1;
1910 	kctl = snd_ctl_new1(&usb_connector_ctl_ro, cval);
1911 	if (!kctl) {
1912 		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
1913 		usb_mixer_elem_info_free(cval);
1914 		return;
1915 	}
1916 
1917 	if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name)))
1918 		strlcat(kctl->id.name, " Jack", sizeof(kctl->id.name));
1919 	else
1920 		get_connector_control_name(mixer, term, is_input, kctl->id.name,
1921 					   sizeof(kctl->id.name));
1922 	kctl->private_free = snd_usb_mixer_elem_free;
1923 	snd_usb_mixer_add_control(&cval->head, kctl);
1924 }
1925 
1926 static int parse_clock_source_unit(struct mixer_build *state, int unitid,
1927 				   void *_ftr)
1928 {
1929 	struct uac_clock_source_descriptor *hdr = _ftr;
1930 	struct usb_mixer_elem_info *cval;
1931 	struct snd_kcontrol *kctl;
1932 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
1933 	int ret;
1934 
1935 	if (state->mixer->protocol != UAC_VERSION_2)
1936 		return -EINVAL;
1937 
1938 	/*
1939 	 * The only property of this unit we are interested in is the
1940 	 * clock source validity. If that isn't readable, just bail out.
1941 	 */
1942 	if (!uac_v2v3_control_is_readable(hdr->bmControls,
1943 				      UAC2_CS_CONTROL_CLOCK_VALID))
1944 		return 0;
1945 
1946 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1947 	if (!cval)
1948 		return -ENOMEM;
1949 
1950 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, hdr->bClockID);
1951 
1952 	cval->min = 0;
1953 	cval->max = 1;
1954 	cval->channels = 1;
1955 	cval->val_type = USB_MIXER_BOOLEAN;
1956 	cval->control = UAC2_CS_CONTROL_CLOCK_VALID;
1957 
1958 	cval->master_readonly = 1;
1959 	/* From UAC2 5.2.5.1.2 "Only the get request is supported." */
1960 	kctl = snd_ctl_new1(&usb_bool_master_control_ctl_ro, cval);
1961 
1962 	if (!kctl) {
1963 		usb_mixer_elem_info_free(cval);
1964 		return -ENOMEM;
1965 	}
1966 
1967 	kctl->private_free = snd_usb_mixer_elem_free;
1968 	ret = snd_usb_copy_string_desc(state->chip, hdr->iClockSource,
1969 				       name, sizeof(name));
1970 	if (ret > 0)
1971 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1972 			 "%s Validity", name);
1973 	else
1974 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1975 			 "Clock Source %d Validity", hdr->bClockID);
1976 
1977 	return snd_usb_mixer_add_control(&cval->head, kctl);
1978 }
1979 
1980 /*
1981  * parse a feature unit
1982  *
1983  * most of controls are defined here.
1984  */
1985 static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
1986 				    void *_ftr)
1987 {
1988 	int channels, i, j;
1989 	struct usb_audio_term iterm;
1990 	unsigned int master_bits;
1991 	int err, csize;
1992 	struct uac_feature_unit_descriptor *hdr = _ftr;
1993 	__u8 *bmaControls;
1994 
1995 	if (state->mixer->protocol == UAC_VERSION_1) {
1996 		csize = hdr->bControlSize;
1997 		channels = (hdr->bLength - 7) / csize - 1;
1998 		bmaControls = hdr->bmaControls;
1999 	} else if (state->mixer->protocol == UAC_VERSION_2) {
2000 		struct uac2_feature_unit_descriptor *ftr = _ftr;
2001 		csize = 4;
2002 		channels = (hdr->bLength - 6) / 4 - 1;
2003 		bmaControls = ftr->bmaControls;
2004 	} else { /* UAC_VERSION_3 */
2005 		struct uac3_feature_unit_descriptor *ftr = _ftr;
2006 
2007 		csize = 4;
2008 		channels = (ftr->bLength - 7) / 4 - 1;
2009 		bmaControls = ftr->bmaControls;
2010 	}
2011 
2012 	/* parse the source unit */
2013 	err = parse_audio_unit(state, hdr->bSourceID);
2014 	if (err < 0)
2015 		return err;
2016 
2017 	/* determine the input source type and name */
2018 	err = check_input_term(state, hdr->bSourceID, &iterm);
2019 	if (err < 0)
2020 		return err;
2021 
2022 	master_bits = snd_usb_combine_bytes(bmaControls, csize);
2023 	/* master configuration quirks */
2024 	switch (state->chip->usb_id) {
2025 	case USB_ID(0x08bb, 0x2702):
2026 		usb_audio_info(state->chip,
2027 			       "usbmixer: master volume quirk for PCM2702 chip\n");
2028 		/* disable non-functional volume control */
2029 		master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
2030 		break;
2031 	case USB_ID(0x1130, 0xf211):
2032 		usb_audio_info(state->chip,
2033 			       "usbmixer: volume control quirk for Tenx TP6911 Audio Headset\n");
2034 		/* disable non-functional volume control */
2035 		channels = 0;
2036 		break;
2037 
2038 	}
2039 
2040 	if (state->mixer->protocol == UAC_VERSION_1) {
2041 		/* check all control types */
2042 		for (i = 0; i < 10; i++) {
2043 			unsigned int ch_bits = 0;
2044 			int control = audio_feature_info[i].control;
2045 
2046 			for (j = 0; j < channels; j++) {
2047 				unsigned int mask;
2048 
2049 				mask = snd_usb_combine_bytes(bmaControls +
2050 							     csize * (j+1), csize);
2051 				if (mask & (1 << i))
2052 					ch_bits |= (1 << j);
2053 			}
2054 			/* audio class v1 controls are never read-only */
2055 
2056 			/*
2057 			 * The first channel must be set
2058 			 * (for ease of programming).
2059 			 */
2060 			if (ch_bits & 1)
2061 				build_feature_ctl(state, _ftr, ch_bits, control,
2062 						  &iterm, unitid, 0);
2063 			if (master_bits & (1 << i))
2064 				build_feature_ctl(state, _ftr, 0, control,
2065 						  &iterm, unitid, 0);
2066 		}
2067 	} else { /* UAC_VERSION_2/3 */
2068 		for (i = 0; i < ARRAY_SIZE(audio_feature_info); i++) {
2069 			unsigned int ch_bits = 0;
2070 			unsigned int ch_read_only = 0;
2071 			int control = audio_feature_info[i].control;
2072 
2073 			for (j = 0; j < channels; j++) {
2074 				unsigned int mask;
2075 
2076 				mask = snd_usb_combine_bytes(bmaControls +
2077 							     csize * (j+1), csize);
2078 				if (uac_v2v3_control_is_readable(mask, control)) {
2079 					ch_bits |= (1 << j);
2080 					if (!uac_v2v3_control_is_writeable(mask, control))
2081 						ch_read_only |= (1 << j);
2082 				}
2083 			}
2084 
2085 			/*
2086 			 * NOTE: build_feature_ctl() will mark the control
2087 			 * read-only if all channels are marked read-only in
2088 			 * the descriptors. Otherwise, the control will be
2089 			 * reported as writeable, but the driver will not
2090 			 * actually issue a write command for read-only
2091 			 * channels.
2092 			 */
2093 
2094 			/*
2095 			 * The first channel must be set
2096 			 * (for ease of programming).
2097 			 */
2098 			if (ch_bits & 1)
2099 				build_feature_ctl(state, _ftr, ch_bits, control,
2100 						  &iterm, unitid, ch_read_only);
2101 			if (uac_v2v3_control_is_readable(master_bits, control))
2102 				build_feature_ctl(state, _ftr, 0, control,
2103 						  &iterm, unitid,
2104 						  !uac_v2v3_control_is_writeable(master_bits,
2105 										 control));
2106 		}
2107 	}
2108 
2109 	return 0;
2110 }
2111 
2112 /*
2113  * Mixer Unit
2114  */
2115 
2116 /* check whether the given in/out overflows bmMixerControls matrix */
2117 static bool mixer_bitmap_overflow(struct uac_mixer_unit_descriptor *desc,
2118 				  int protocol, int num_ins, int num_outs)
2119 {
2120 	u8 *hdr = (u8 *)desc;
2121 	u8 *c = uac_mixer_unit_bmControls(desc, protocol);
2122 	size_t rest; /* remaining bytes after bmMixerControls */
2123 
2124 	switch (protocol) {
2125 	case UAC_VERSION_1:
2126 	default:
2127 		rest = 1; /* iMixer */
2128 		break;
2129 	case UAC_VERSION_2:
2130 		rest = 2; /* bmControls + iMixer */
2131 		break;
2132 	case UAC_VERSION_3:
2133 		rest = 6; /* bmControls + wMixerDescrStr */
2134 		break;
2135 	}
2136 
2137 	/* overflow? */
2138 	return c + (num_ins * num_outs + 7) / 8 + rest > hdr + hdr[0];
2139 }
2140 
2141 /*
2142  * build a mixer unit control
2143  *
2144  * the callbacks are identical with feature unit.
2145  * input channel number (zero based) is given in control field instead.
2146  */
2147 static void build_mixer_unit_ctl(struct mixer_build *state,
2148 				 struct uac_mixer_unit_descriptor *desc,
2149 				 int in_pin, int in_ch, int num_outs,
2150 				 int unitid, struct usb_audio_term *iterm)
2151 {
2152 	struct usb_mixer_elem_info *cval;
2153 	unsigned int i, len;
2154 	struct snd_kcontrol *kctl;
2155 	const struct usbmix_name_map *map;
2156 
2157 	map = find_map(state->map, unitid, 0);
2158 	if (check_ignored_ctl(map))
2159 		return;
2160 
2161 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2162 	if (!cval)
2163 		return;
2164 
2165 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2166 	cval->control = in_ch + 1; /* based on 1 */
2167 	cval->val_type = USB_MIXER_S16;
2168 	for (i = 0; i < num_outs; i++) {
2169 		__u8 *c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
2170 
2171 		if (check_matrix_bitmap(c, in_ch, i, num_outs)) {
2172 			cval->cmask |= (1 << i);
2173 			cval->channels++;
2174 		}
2175 	}
2176 
2177 	/* get min/max values */
2178 	get_min_max(cval, 0);
2179 
2180 	kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
2181 	if (!kctl) {
2182 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2183 		usb_mixer_elem_info_free(cval);
2184 		return;
2185 	}
2186 	kctl->private_free = snd_usb_mixer_elem_free;
2187 
2188 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2189 	if (!len)
2190 		len = get_term_name(state->chip, iterm, kctl->id.name,
2191 				    sizeof(kctl->id.name), 0);
2192 	if (!len)
2193 		len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
2194 	append_ctl_name(kctl, " Volume");
2195 
2196 	usb_audio_dbg(state->chip, "[%d] MU [%s] ch = %d, val = %d/%d\n",
2197 		    cval->head.id, kctl->id.name, cval->channels, cval->min, cval->max);
2198 	snd_usb_mixer_add_control(&cval->head, kctl);
2199 }
2200 
2201 static int parse_audio_input_terminal(struct mixer_build *state, int unitid,
2202 				      void *raw_desc)
2203 {
2204 	struct usb_audio_term iterm;
2205 	unsigned int control, bmctls, term_id;
2206 
2207 	if (state->mixer->protocol == UAC_VERSION_2) {
2208 		struct uac2_input_terminal_descriptor *d_v2 = raw_desc;
2209 		control = UAC2_TE_CONNECTOR;
2210 		term_id = d_v2->bTerminalID;
2211 		bmctls = le16_to_cpu(d_v2->bmControls);
2212 	} else if (state->mixer->protocol == UAC_VERSION_3) {
2213 		struct uac3_input_terminal_descriptor *d_v3 = raw_desc;
2214 		control = UAC3_TE_INSERTION;
2215 		term_id = d_v3->bTerminalID;
2216 		bmctls = le32_to_cpu(d_v3->bmControls);
2217 	} else {
2218 		return 0; /* UAC1. No Insertion control */
2219 	}
2220 
2221 	check_input_term(state, term_id, &iterm);
2222 
2223 	/* Check for jack detection. */
2224 	if ((iterm.type & 0xff00) != 0x0100 &&
2225 	    uac_v2v3_control_is_readable(bmctls, control))
2226 		build_connector_control(state->mixer, state->map, &iterm, true);
2227 
2228 	return 0;
2229 }
2230 
2231 /*
2232  * parse a mixer unit
2233  */
2234 static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
2235 				  void *raw_desc)
2236 {
2237 	struct uac_mixer_unit_descriptor *desc = raw_desc;
2238 	struct usb_audio_term iterm;
2239 	int input_pins, num_ins, num_outs;
2240 	int pin, ich, err;
2241 
2242 	err = uac_mixer_unit_get_channels(state, desc);
2243 	if (err < 0) {
2244 		usb_audio_err(state->chip,
2245 			      "invalid MIXER UNIT descriptor %d\n",
2246 			      unitid);
2247 		return err;
2248 	}
2249 
2250 	num_outs = err;
2251 	input_pins = desc->bNrInPins;
2252 
2253 	num_ins = 0;
2254 	ich = 0;
2255 	for (pin = 0; pin < input_pins; pin++) {
2256 		err = parse_audio_unit(state, desc->baSourceID[pin]);
2257 		if (err < 0)
2258 			continue;
2259 		/* no bmControls field (e.g. Maya44) -> ignore */
2260 		if (!num_outs)
2261 			continue;
2262 		err = check_input_term(state, desc->baSourceID[pin], &iterm);
2263 		if (err < 0)
2264 			return err;
2265 		num_ins += iterm.channels;
2266 		if (mixer_bitmap_overflow(desc, state->mixer->protocol,
2267 					  num_ins, num_outs))
2268 			break;
2269 		for (; ich < num_ins; ich++) {
2270 			int och, ich_has_controls = 0;
2271 
2272 			for (och = 0; och < num_outs; och++) {
2273 				__u8 *c = uac_mixer_unit_bmControls(desc,
2274 						state->mixer->protocol);
2275 
2276 				if (check_matrix_bitmap(c, ich, och, num_outs)) {
2277 					ich_has_controls = 1;
2278 					break;
2279 				}
2280 			}
2281 			if (ich_has_controls)
2282 				build_mixer_unit_ctl(state, desc, pin, ich, num_outs,
2283 						     unitid, &iterm);
2284 		}
2285 	}
2286 	return 0;
2287 }
2288 
2289 /*
2290  * Processing Unit / Extension Unit
2291  */
2292 
2293 /* get callback for processing/extension unit */
2294 static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol,
2295 				  struct snd_ctl_elem_value *ucontrol)
2296 {
2297 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2298 	int err, val;
2299 
2300 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2301 	if (err < 0) {
2302 		ucontrol->value.integer.value[0] = cval->min;
2303 		return filter_error(cval, err);
2304 	}
2305 	val = get_relative_value(cval, val);
2306 	ucontrol->value.integer.value[0] = val;
2307 	return 0;
2308 }
2309 
2310 /* put callback for processing/extension unit */
2311 static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol,
2312 				  struct snd_ctl_elem_value *ucontrol)
2313 {
2314 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2315 	int val, oval, err;
2316 
2317 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2318 	if (err < 0)
2319 		return filter_error(cval, err);
2320 	val = ucontrol->value.integer.value[0];
2321 	val = get_abs_value(cval, val);
2322 	if (val != oval) {
2323 		set_cur_ctl_value(cval, cval->control << 8, val);
2324 		return 1;
2325 	}
2326 	return 0;
2327 }
2328 
2329 /* alsa control interface for processing/extension unit */
2330 static const struct snd_kcontrol_new mixer_procunit_ctl = {
2331 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2332 	.name = "", /* will be filled later */
2333 	.info = mixer_ctl_feature_info,
2334 	.get = mixer_ctl_procunit_get,
2335 	.put = mixer_ctl_procunit_put,
2336 };
2337 
2338 /*
2339  * predefined data for processing units
2340  */
2341 struct procunit_value_info {
2342 	int control;
2343 	const char *suffix;
2344 	int val_type;
2345 	int min_value;
2346 };
2347 
2348 struct procunit_info {
2349 	int type;
2350 	char *name;
2351 	const struct procunit_value_info *values;
2352 };
2353 
2354 static const struct procunit_value_info undefined_proc_info[] = {
2355 	{ 0x00, "Control Undefined", 0 },
2356 	{ 0 }
2357 };
2358 
2359 static const struct procunit_value_info updown_proc_info[] = {
2360 	{ UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2361 	{ UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2362 	{ 0 }
2363 };
2364 static const struct procunit_value_info prologic_proc_info[] = {
2365 	{ UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2366 	{ UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2367 	{ 0 }
2368 };
2369 static const struct procunit_value_info threed_enh_proc_info[] = {
2370 	{ UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2371 	{ UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
2372 	{ 0 }
2373 };
2374 static const struct procunit_value_info reverb_proc_info[] = {
2375 	{ UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2376 	{ UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
2377 	{ UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
2378 	{ UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
2379 	{ 0 }
2380 };
2381 static const struct procunit_value_info chorus_proc_info[] = {
2382 	{ UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2383 	{ UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
2384 	{ UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
2385 	{ UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
2386 	{ 0 }
2387 };
2388 static const struct procunit_value_info dcr_proc_info[] = {
2389 	{ UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2390 	{ UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
2391 	{ UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
2392 	{ UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
2393 	{ UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
2394 	{ UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
2395 	{ 0 }
2396 };
2397 
2398 static const struct procunit_info procunits[] = {
2399 	{ UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
2400 	{ UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
2401 	{ UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
2402 	{ UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
2403 	{ UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
2404 	{ UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
2405 	{ 0 },
2406 };
2407 
2408 static const struct procunit_value_info uac3_updown_proc_info[] = {
2409 	{ UAC3_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2410 	{ 0 }
2411 };
2412 static const struct procunit_value_info uac3_stereo_ext_proc_info[] = {
2413 	{ UAC3_EXT_WIDTH_CONTROL, "Width Control", USB_MIXER_U8 },
2414 	{ 0 }
2415 };
2416 
2417 static const struct procunit_info uac3_procunits[] = {
2418 	{ UAC3_PROCESS_UP_DOWNMIX, "Up Down", uac3_updown_proc_info },
2419 	{ UAC3_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", uac3_stereo_ext_proc_info },
2420 	{ UAC3_PROCESS_MULTI_FUNCTION, "Multi-Function", undefined_proc_info },
2421 	{ 0 },
2422 };
2423 
2424 /*
2425  * predefined data for extension units
2426  */
2427 static const struct procunit_value_info clock_rate_xu_info[] = {
2428 	{ USB_XU_CLOCK_RATE_SELECTOR, "Selector", USB_MIXER_U8, 0 },
2429 	{ 0 }
2430 };
2431 static const struct procunit_value_info clock_source_xu_info[] = {
2432 	{ USB_XU_CLOCK_SOURCE_SELECTOR, "External", USB_MIXER_BOOLEAN },
2433 	{ 0 }
2434 };
2435 static const struct procunit_value_info spdif_format_xu_info[] = {
2436 	{ USB_XU_DIGITAL_FORMAT_SELECTOR, "SPDIF/AC3", USB_MIXER_BOOLEAN },
2437 	{ 0 }
2438 };
2439 static const struct procunit_value_info soft_limit_xu_info[] = {
2440 	{ USB_XU_SOFT_LIMIT_SELECTOR, " ", USB_MIXER_BOOLEAN },
2441 	{ 0 }
2442 };
2443 static const struct procunit_info extunits[] = {
2444 	{ USB_XU_CLOCK_RATE, "Clock rate", clock_rate_xu_info },
2445 	{ USB_XU_CLOCK_SOURCE, "DigitalIn CLK source", clock_source_xu_info },
2446 	{ USB_XU_DIGITAL_IO_STATUS, "DigitalOut format:", spdif_format_xu_info },
2447 	{ USB_XU_DEVICE_OPTIONS, "AnalogueIn Soft Limit", soft_limit_xu_info },
2448 	{ 0 }
2449 };
2450 
2451 /*
2452  * build a processing/extension unit
2453  */
2454 static int build_audio_procunit(struct mixer_build *state, int unitid,
2455 				void *raw_desc, const struct procunit_info *list,
2456 				bool extension_unit)
2457 {
2458 	struct uac_processing_unit_descriptor *desc = raw_desc;
2459 	int num_ins;
2460 	struct usb_mixer_elem_info *cval;
2461 	struct snd_kcontrol *kctl;
2462 	int i, err, nameid, type, len, val;
2463 	const struct procunit_info *info;
2464 	const struct procunit_value_info *valinfo;
2465 	const struct usbmix_name_map *map;
2466 	static const struct procunit_value_info default_value_info[] = {
2467 		{ 0x01, "Switch", USB_MIXER_BOOLEAN },
2468 		{ 0 }
2469 	};
2470 	static const struct procunit_info default_info = {
2471 		0, NULL, default_value_info
2472 	};
2473 	const char *name = extension_unit ?
2474 		"Extension Unit" : "Processing Unit";
2475 
2476 	num_ins = desc->bNrInPins;
2477 	for (i = 0; i < num_ins; i++) {
2478 		err = parse_audio_unit(state, desc->baSourceID[i]);
2479 		if (err < 0)
2480 			return err;
2481 	}
2482 
2483 	type = le16_to_cpu(desc->wProcessType);
2484 	for (info = list; info && info->type; info++)
2485 		if (info->type == type)
2486 			break;
2487 	if (!info || !info->type)
2488 		info = &default_info;
2489 
2490 	for (valinfo = info->values; valinfo->control; valinfo++) {
2491 		__u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);
2492 
2493 		if (state->mixer->protocol == UAC_VERSION_1) {
2494 			if (!(controls[valinfo->control / 8] &
2495 					(1 << ((valinfo->control % 8) - 1))))
2496 				continue;
2497 		} else { /* UAC_VERSION_2/3 */
2498 			if (!uac_v2v3_control_is_readable(controls[valinfo->control / 8],
2499 							  valinfo->control))
2500 				continue;
2501 		}
2502 
2503 		map = find_map(state->map, unitid, valinfo->control);
2504 		if (check_ignored_ctl(map))
2505 			continue;
2506 		cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2507 		if (!cval)
2508 			return -ENOMEM;
2509 		snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2510 		cval->control = valinfo->control;
2511 		cval->val_type = valinfo->val_type;
2512 		cval->channels = 1;
2513 
2514 		if (state->mixer->protocol > UAC_VERSION_1 &&
2515 		    !uac_v2v3_control_is_writeable(controls[valinfo->control / 8],
2516 						   valinfo->control))
2517 			cval->master_readonly = 1;
2518 
2519 		/* get min/max values */
2520 		switch (type) {
2521 		case UAC_PROCESS_UP_DOWNMIX: {
2522 			bool mode_sel = false;
2523 
2524 			switch (state->mixer->protocol) {
2525 			case UAC_VERSION_1:
2526 			case UAC_VERSION_2:
2527 			default:
2528 				if (cval->control == UAC_UD_MODE_SELECT)
2529 					mode_sel = true;
2530 				break;
2531 			case UAC_VERSION_3:
2532 				if (cval->control == UAC3_UD_MODE_SELECT)
2533 					mode_sel = true;
2534 				break;
2535 			}
2536 
2537 			if (mode_sel) {
2538 				__u8 *control_spec = uac_processing_unit_specific(desc,
2539 								state->mixer->protocol);
2540 				cval->min = 1;
2541 				cval->max = control_spec[0];
2542 				cval->res = 1;
2543 				cval->initialized = 1;
2544 				break;
2545 			}
2546 
2547 			get_min_max(cval, valinfo->min_value);
2548 			break;
2549 		}
2550 		case USB_XU_CLOCK_RATE:
2551 			/*
2552 			 * E-Mu USB 0404/0202/TrackerPre/0204
2553 			 * samplerate control quirk
2554 			 */
2555 			cval->min = 0;
2556 			cval->max = 5;
2557 			cval->res = 1;
2558 			cval->initialized = 1;
2559 			break;
2560 		default:
2561 			get_min_max(cval, valinfo->min_value);
2562 			break;
2563 		}
2564 
2565 		err = get_cur_ctl_value(cval, cval->control << 8, &val);
2566 		if (err < 0) {
2567 			usb_mixer_elem_info_free(cval);
2568 			return -EINVAL;
2569 		}
2570 
2571 		kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
2572 		if (!kctl) {
2573 			usb_mixer_elem_info_free(cval);
2574 			return -ENOMEM;
2575 		}
2576 		kctl->private_free = snd_usb_mixer_elem_free;
2577 
2578 		if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name))) {
2579 			/* nothing */ ;
2580 		} else if (info->name) {
2581 			strscpy(kctl->id.name, info->name, sizeof(kctl->id.name));
2582 		} else {
2583 			if (extension_unit)
2584 				nameid = uac_extension_unit_iExtension(desc, state->mixer->protocol);
2585 			else
2586 				nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
2587 			len = 0;
2588 			if (nameid)
2589 				len = snd_usb_copy_string_desc(state->chip,
2590 							       nameid,
2591 							       kctl->id.name,
2592 							       sizeof(kctl->id.name));
2593 			if (!len)
2594 				strscpy(kctl->id.name, name, sizeof(kctl->id.name));
2595 		}
2596 		append_ctl_name(kctl, " ");
2597 		append_ctl_name(kctl, valinfo->suffix);
2598 
2599 		usb_audio_dbg(state->chip,
2600 			      "[%d] PU [%s] ch = %d, val = %d/%d\n",
2601 			      cval->head.id, kctl->id.name, cval->channels,
2602 			      cval->min, cval->max);
2603 
2604 		err = snd_usb_mixer_add_control(&cval->head, kctl);
2605 		if (err < 0)
2606 			return err;
2607 	}
2608 	return 0;
2609 }
2610 
2611 static int parse_audio_processing_unit(struct mixer_build *state, int unitid,
2612 				       void *raw_desc)
2613 {
2614 	switch (state->mixer->protocol) {
2615 	case UAC_VERSION_1:
2616 	case UAC_VERSION_2:
2617 	default:
2618 		return build_audio_procunit(state, unitid, raw_desc,
2619 					    procunits, false);
2620 	case UAC_VERSION_3:
2621 		return build_audio_procunit(state, unitid, raw_desc,
2622 					    uac3_procunits, false);
2623 	}
2624 }
2625 
2626 static int parse_audio_extension_unit(struct mixer_build *state, int unitid,
2627 				      void *raw_desc)
2628 {
2629 	/*
2630 	 * Note that we parse extension units with processing unit descriptors.
2631 	 * That's ok as the layout is the same.
2632 	 */
2633 	return build_audio_procunit(state, unitid, raw_desc, extunits, true);
2634 }
2635 
2636 /*
2637  * Selector Unit
2638  */
2639 
2640 /*
2641  * info callback for selector unit
2642  * use an enumerator type for routing
2643  */
2644 static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol,
2645 				   struct snd_ctl_elem_info *uinfo)
2646 {
2647 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2648 	const char **itemlist = (const char **)kcontrol->private_value;
2649 
2650 	if (snd_BUG_ON(!itemlist))
2651 		return -EINVAL;
2652 	return snd_ctl_enum_info(uinfo, 1, cval->max, itemlist);
2653 }
2654 
2655 /* get callback for selector unit */
2656 static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol,
2657 				  struct snd_ctl_elem_value *ucontrol)
2658 {
2659 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2660 	int val, err;
2661 
2662 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2663 	if (err < 0) {
2664 		ucontrol->value.enumerated.item[0] = 0;
2665 		return filter_error(cval, err);
2666 	}
2667 	val = get_relative_value(cval, val);
2668 	ucontrol->value.enumerated.item[0] = val;
2669 	return 0;
2670 }
2671 
2672 /* put callback for selector unit */
2673 static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol,
2674 				  struct snd_ctl_elem_value *ucontrol)
2675 {
2676 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2677 	int val, oval, err;
2678 
2679 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2680 	if (err < 0)
2681 		return filter_error(cval, err);
2682 	val = ucontrol->value.enumerated.item[0];
2683 	val = get_abs_value(cval, val);
2684 	if (val != oval) {
2685 		set_cur_ctl_value(cval, cval->control << 8, val);
2686 		return 1;
2687 	}
2688 	return 0;
2689 }
2690 
2691 /* alsa control interface for selector unit */
2692 static const struct snd_kcontrol_new mixer_selectunit_ctl = {
2693 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2694 	.name = "", /* will be filled later */
2695 	.info = mixer_ctl_selector_info,
2696 	.get = mixer_ctl_selector_get,
2697 	.put = mixer_ctl_selector_put,
2698 };
2699 
2700 /*
2701  * private free callback.
2702  * free both private_data and private_value
2703  */
2704 static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
2705 {
2706 	int i, num_ins = 0;
2707 
2708 	if (kctl->private_data) {
2709 		struct usb_mixer_elem_info *cval = kctl->private_data;
2710 		num_ins = cval->max;
2711 		usb_mixer_elem_info_free(cval);
2712 		kctl->private_data = NULL;
2713 	}
2714 	if (kctl->private_value) {
2715 		char **itemlist = (char **)kctl->private_value;
2716 		for (i = 0; i < num_ins; i++)
2717 			kfree(itemlist[i]);
2718 		kfree(itemlist);
2719 		kctl->private_value = 0;
2720 	}
2721 }
2722 
2723 /*
2724  * parse a selector unit
2725  */
2726 static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
2727 				     void *raw_desc)
2728 {
2729 	struct uac_selector_unit_descriptor *desc = raw_desc;
2730 	unsigned int i, nameid, len;
2731 	int err;
2732 	struct usb_mixer_elem_info *cval;
2733 	struct snd_kcontrol *kctl;
2734 	const struct usbmix_name_map *map;
2735 	char **namelist;
2736 
2737 	for (i = 0; i < desc->bNrInPins; i++) {
2738 		err = parse_audio_unit(state, desc->baSourceID[i]);
2739 		if (err < 0)
2740 			return err;
2741 	}
2742 
2743 	if (desc->bNrInPins == 1) /* only one ? nonsense! */
2744 		return 0;
2745 
2746 	map = find_map(state->map, unitid, 0);
2747 	if (check_ignored_ctl(map))
2748 		return 0;
2749 
2750 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2751 	if (!cval)
2752 		return -ENOMEM;
2753 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2754 	cval->val_type = USB_MIXER_U8;
2755 	cval->channels = 1;
2756 	cval->min = 1;
2757 	cval->max = desc->bNrInPins;
2758 	cval->res = 1;
2759 	cval->initialized = 1;
2760 
2761 	switch (state->mixer->protocol) {
2762 	case UAC_VERSION_1:
2763 	default:
2764 		cval->control = 0;
2765 		break;
2766 	case UAC_VERSION_2:
2767 	case UAC_VERSION_3:
2768 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
2769 		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
2770 			cval->control = UAC2_CX_CLOCK_SELECTOR;
2771 		else /* UAC2/3_SELECTOR_UNIT */
2772 			cval->control = UAC2_SU_SELECTOR;
2773 		break;
2774 	}
2775 
2776 	namelist = kcalloc(desc->bNrInPins, sizeof(char *), GFP_KERNEL);
2777 	if (!namelist) {
2778 		err = -ENOMEM;
2779 		goto error_cval;
2780 	}
2781 #define MAX_ITEM_NAME_LEN	64
2782 	for (i = 0; i < desc->bNrInPins; i++) {
2783 		struct usb_audio_term iterm;
2784 		namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
2785 		if (!namelist[i]) {
2786 			err = -ENOMEM;
2787 			goto error_name;
2788 		}
2789 		len = check_mapped_selector_name(state, unitid, i, namelist[i],
2790 						 MAX_ITEM_NAME_LEN);
2791 		if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
2792 			len = get_term_name(state->chip, &iterm, namelist[i],
2793 					    MAX_ITEM_NAME_LEN, 0);
2794 		if (! len)
2795 			sprintf(namelist[i], "Input %u", i);
2796 	}
2797 
2798 	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
2799 	if (! kctl) {
2800 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2801 		err = -ENOMEM;
2802 		goto error_name;
2803 	}
2804 	kctl->private_value = (unsigned long)namelist;
2805 	kctl->private_free = usb_mixer_selector_elem_free;
2806 
2807 	/* check the static mapping table at first */
2808 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2809 	if (!len) {
2810 		/* no mapping ? */
2811 		switch (state->mixer->protocol) {
2812 		case UAC_VERSION_1:
2813 		case UAC_VERSION_2:
2814 		default:
2815 		/* if iSelector is given, use it */
2816 			nameid = uac_selector_unit_iSelector(desc);
2817 			if (nameid)
2818 				len = snd_usb_copy_string_desc(state->chip,
2819 							nameid, kctl->id.name,
2820 							sizeof(kctl->id.name));
2821 			break;
2822 		case UAC_VERSION_3:
2823 			/* TODO: Class-Specific strings not yet supported */
2824 			break;
2825 		}
2826 
2827 		/* ... or pick up the terminal name at next */
2828 		if (!len)
2829 			len = get_term_name(state->chip, &state->oterm,
2830 				    kctl->id.name, sizeof(kctl->id.name), 0);
2831 		/* ... or use the fixed string "USB" as the last resort */
2832 		if (!len)
2833 			strscpy(kctl->id.name, "USB", sizeof(kctl->id.name));
2834 
2835 		/* and add the proper suffix */
2836 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
2837 		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
2838 			append_ctl_name(kctl, " Clock Source");
2839 		else if ((state->oterm.type & 0xff00) == 0x0100)
2840 			append_ctl_name(kctl, " Capture Source");
2841 		else
2842 			append_ctl_name(kctl, " Playback Source");
2843 	}
2844 
2845 	usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
2846 		    cval->head.id, kctl->id.name, desc->bNrInPins);
2847 	return snd_usb_mixer_add_control(&cval->head, kctl);
2848 
2849  error_name:
2850 	for (i = 0; i < desc->bNrInPins; i++)
2851 		kfree(namelist[i]);
2852 	kfree(namelist);
2853  error_cval:
2854 	usb_mixer_elem_info_free(cval);
2855 	return err;
2856 }
2857 
2858 /*
2859  * parse an audio unit recursively
2860  */
2861 
2862 static int parse_audio_unit(struct mixer_build *state, int unitid)
2863 {
2864 	unsigned char *p1;
2865 	int protocol = state->mixer->protocol;
2866 
2867 	if (test_and_set_bit(unitid, state->unitbitmap))
2868 		return 0; /* the unit already visited */
2869 
2870 	p1 = find_audio_control_unit(state, unitid);
2871 	if (!p1) {
2872 		usb_audio_err(state->chip, "unit %d not found!\n", unitid);
2873 		return -EINVAL;
2874 	}
2875 
2876 	if (!snd_usb_validate_audio_desc(p1, protocol)) {
2877 		usb_audio_dbg(state->chip, "invalid unit %d\n", unitid);
2878 		return 0; /* skip invalid unit */
2879 	}
2880 
2881 	switch (PTYPE(protocol, p1[2])) {
2882 	case PTYPE(UAC_VERSION_1, UAC_INPUT_TERMINAL):
2883 	case PTYPE(UAC_VERSION_2, UAC_INPUT_TERMINAL):
2884 	case PTYPE(UAC_VERSION_3, UAC_INPUT_TERMINAL):
2885 		return parse_audio_input_terminal(state, unitid, p1);
2886 	case PTYPE(UAC_VERSION_1, UAC_MIXER_UNIT):
2887 	case PTYPE(UAC_VERSION_2, UAC_MIXER_UNIT):
2888 	case PTYPE(UAC_VERSION_3, UAC3_MIXER_UNIT):
2889 		return parse_audio_mixer_unit(state, unitid, p1);
2890 	case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SOURCE):
2891 	case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SOURCE):
2892 		return parse_clock_source_unit(state, unitid, p1);
2893 	case PTYPE(UAC_VERSION_1, UAC_SELECTOR_UNIT):
2894 	case PTYPE(UAC_VERSION_2, UAC_SELECTOR_UNIT):
2895 	case PTYPE(UAC_VERSION_3, UAC3_SELECTOR_UNIT):
2896 	case PTYPE(UAC_VERSION_2, UAC2_CLOCK_SELECTOR):
2897 	case PTYPE(UAC_VERSION_3, UAC3_CLOCK_SELECTOR):
2898 		return parse_audio_selector_unit(state, unitid, p1);
2899 	case PTYPE(UAC_VERSION_1, UAC_FEATURE_UNIT):
2900 	case PTYPE(UAC_VERSION_2, UAC_FEATURE_UNIT):
2901 	case PTYPE(UAC_VERSION_3, UAC3_FEATURE_UNIT):
2902 		return parse_audio_feature_unit(state, unitid, p1);
2903 	case PTYPE(UAC_VERSION_1, UAC1_PROCESSING_UNIT):
2904 	case PTYPE(UAC_VERSION_2, UAC2_PROCESSING_UNIT_V2):
2905 	case PTYPE(UAC_VERSION_3, UAC3_PROCESSING_UNIT):
2906 		return parse_audio_processing_unit(state, unitid, p1);
2907 	case PTYPE(UAC_VERSION_1, UAC1_EXTENSION_UNIT):
2908 	case PTYPE(UAC_VERSION_2, UAC2_EXTENSION_UNIT_V2):
2909 	case PTYPE(UAC_VERSION_3, UAC3_EXTENSION_UNIT):
2910 		return parse_audio_extension_unit(state, unitid, p1);
2911 	case PTYPE(UAC_VERSION_2, UAC2_EFFECT_UNIT):
2912 	case PTYPE(UAC_VERSION_3, UAC3_EFFECT_UNIT):
2913 		return 0; /* FIXME - effect units not implemented yet */
2914 	default:
2915 		usb_audio_err(state->chip,
2916 			      "unit %u: unexpected type 0x%02x\n",
2917 			      unitid, p1[2]);
2918 		return -EINVAL;
2919 	}
2920 }
2921 
2922 static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
2923 {
2924 	/* kill pending URBs */
2925 	snd_usb_mixer_disconnect(mixer);
2926 
2927 	kfree(mixer->id_elems);
2928 	if (mixer->urb) {
2929 		kfree(mixer->urb->transfer_buffer);
2930 		usb_free_urb(mixer->urb);
2931 	}
2932 	usb_free_urb(mixer->rc_urb);
2933 	kfree(mixer->rc_setup_packet);
2934 	kfree(mixer);
2935 }
2936 
2937 static int snd_usb_mixer_dev_free(struct snd_device *device)
2938 {
2939 	struct usb_mixer_interface *mixer = device->device_data;
2940 	snd_usb_mixer_free(mixer);
2941 	return 0;
2942 }
2943 
2944 /* UAC3 predefined channels configuration */
2945 struct uac3_badd_profile {
2946 	int subclass;
2947 	const char *name;
2948 	int c_chmask;	/* capture channels mask */
2949 	int p_chmask;	/* playback channels mask */
2950 	int st_chmask;	/* side tone mixing channel mask */
2951 };
2952 
2953 static const struct uac3_badd_profile uac3_badd_profiles[] = {
2954 	{
2955 		/*
2956 		 * BAIF, BAOF or combination of both
2957 		 * IN: Mono or Stereo cfg, Mono alt possible
2958 		 * OUT: Mono or Stereo cfg, Mono alt possible
2959 		 */
2960 		.subclass = UAC3_FUNCTION_SUBCLASS_GENERIC_IO,
2961 		.name = "GENERIC IO",
2962 		.c_chmask = -1,		/* dynamic channels */
2963 		.p_chmask = -1,		/* dynamic channels */
2964 	},
2965 	{
2966 		/* BAOF; Stereo only cfg, Mono alt possible */
2967 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADPHONE,
2968 		.name = "HEADPHONE",
2969 		.p_chmask = 3,
2970 	},
2971 	{
2972 		/* BAOF; Mono or Stereo cfg, Mono alt possible */
2973 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKER,
2974 		.name = "SPEAKER",
2975 		.p_chmask = -1,		/* dynamic channels */
2976 	},
2977 	{
2978 		/* BAIF; Mono or Stereo cfg, Mono alt possible */
2979 		.subclass = UAC3_FUNCTION_SUBCLASS_MICROPHONE,
2980 		.name = "MICROPHONE",
2981 		.c_chmask = -1,		/* dynamic channels */
2982 	},
2983 	{
2984 		/*
2985 		 * BAIOF topology
2986 		 * IN: Mono only
2987 		 * OUT: Mono or Stereo cfg, Mono alt possible
2988 		 */
2989 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET,
2990 		.name = "HEADSET",
2991 		.c_chmask = 1,
2992 		.p_chmask = -1,		/* dynamic channels */
2993 		.st_chmask = 1,
2994 	},
2995 	{
2996 		/* BAIOF; IN: Mono only; OUT: Stereo only, Mono alt possible */
2997 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER,
2998 		.name = "HEADSET ADAPTER",
2999 		.c_chmask = 1,
3000 		.p_chmask = 3,
3001 		.st_chmask = 1,
3002 	},
3003 	{
3004 		/* BAIF + BAOF; IN: Mono only; OUT: Mono only */
3005 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE,
3006 		.name = "SPEAKERPHONE",
3007 		.c_chmask = 1,
3008 		.p_chmask = 1,
3009 	},
3010 	{ 0 } /* terminator */
3011 };
3012 
3013 static bool uac3_badd_func_has_valid_channels(struct usb_mixer_interface *mixer,
3014 					      const struct uac3_badd_profile *f,
3015 					      int c_chmask, int p_chmask)
3016 {
3017 	/*
3018 	 * If both playback/capture channels are dynamic, make sure
3019 	 * at least one channel is present
3020 	 */
3021 	if (f->c_chmask < 0 && f->p_chmask < 0) {
3022 		if (!c_chmask && !p_chmask) {
3023 			usb_audio_warn(mixer->chip, "BAAD %s: no channels?",
3024 				       f->name);
3025 			return false;
3026 		}
3027 		return true;
3028 	}
3029 
3030 	if ((f->c_chmask < 0 && !c_chmask) ||
3031 	    (f->c_chmask >= 0 && f->c_chmask != c_chmask)) {
3032 		usb_audio_warn(mixer->chip, "BAAD %s c_chmask mismatch",
3033 			       f->name);
3034 		return false;
3035 	}
3036 	if ((f->p_chmask < 0 && !p_chmask) ||
3037 	    (f->p_chmask >= 0 && f->p_chmask != p_chmask)) {
3038 		usb_audio_warn(mixer->chip, "BAAD %s p_chmask mismatch",
3039 			       f->name);
3040 		return false;
3041 	}
3042 	return true;
3043 }
3044 
3045 /*
3046  * create mixer controls for UAC3 BADD profiles
3047  *
3048  * UAC3 BADD device doesn't contain CS descriptors thus we will guess everything
3049  *
3050  * BADD device may contain Mixer Unit, which doesn't have any controls, skip it
3051  */
3052 static int snd_usb_mixer_controls_badd(struct usb_mixer_interface *mixer,
3053 				       int ctrlif)
3054 {
3055 	struct usb_device *dev = mixer->chip->dev;
3056 	struct usb_interface_assoc_descriptor *assoc;
3057 	int badd_profile = mixer->chip->badd_profile;
3058 	const struct uac3_badd_profile *f;
3059 	const struct usbmix_ctl_map *map;
3060 	int p_chmask = 0, c_chmask = 0, st_chmask = 0;
3061 	int i;
3062 
3063 	assoc = usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
3064 
3065 	/* Detect BADD capture/playback channels from AS EP descriptors */
3066 	for (i = 0; i < assoc->bInterfaceCount; i++) {
3067 		int intf = assoc->bFirstInterface + i;
3068 
3069 		struct usb_interface *iface;
3070 		struct usb_host_interface *alts;
3071 		struct usb_interface_descriptor *altsd;
3072 		unsigned int maxpacksize;
3073 		char dir_in;
3074 		int chmask, num;
3075 
3076 		if (intf == ctrlif)
3077 			continue;
3078 
3079 		iface = usb_ifnum_to_if(dev, intf);
3080 		if (!iface)
3081 			continue;
3082 
3083 		num = iface->num_altsetting;
3084 
3085 		if (num < 2)
3086 			return -EINVAL;
3087 
3088 		/*
3089 		 * The number of Channels in an AudioStreaming interface
3090 		 * and the audio sample bit resolution (16 bits or 24
3091 		 * bits) can be derived from the wMaxPacketSize field in
3092 		 * the Standard AS Audio Data Endpoint descriptor in
3093 		 * Alternate Setting 1
3094 		 */
3095 		alts = &iface->altsetting[1];
3096 		altsd = get_iface_desc(alts);
3097 
3098 		if (altsd->bNumEndpoints < 1)
3099 			return -EINVAL;
3100 
3101 		/* check direction */
3102 		dir_in = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN);
3103 		maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
3104 
3105 		switch (maxpacksize) {
3106 		default:
3107 			usb_audio_err(mixer->chip,
3108 				"incorrect wMaxPacketSize 0x%x for BADD profile\n",
3109 				maxpacksize);
3110 			return -EINVAL;
3111 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_16:
3112 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_16:
3113 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_24:
3114 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_24:
3115 			chmask = 1;
3116 			break;
3117 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_16:
3118 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_16:
3119 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_24:
3120 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_24:
3121 			chmask = 3;
3122 			break;
3123 		}
3124 
3125 		if (dir_in)
3126 			c_chmask = chmask;
3127 		else
3128 			p_chmask = chmask;
3129 	}
3130 
3131 	usb_audio_dbg(mixer->chip,
3132 		"UAC3 BADD profile 0x%x: detected c_chmask=%d p_chmask=%d\n",
3133 		badd_profile, c_chmask, p_chmask);
3134 
3135 	/* check the mapping table */
3136 	for (map = uac3_badd_usbmix_ctl_maps; map->id; map++) {
3137 		if (map->id == badd_profile)
3138 			break;
3139 	}
3140 
3141 	if (!map->id)
3142 		return -EINVAL;
3143 
3144 	for (f = uac3_badd_profiles; f->name; f++) {
3145 		if (badd_profile == f->subclass)
3146 			break;
3147 	}
3148 	if (!f->name)
3149 		return -EINVAL;
3150 	if (!uac3_badd_func_has_valid_channels(mixer, f, c_chmask, p_chmask))
3151 		return -EINVAL;
3152 	st_chmask = f->st_chmask;
3153 
3154 	/* Playback */
3155 	if (p_chmask) {
3156 		/* Master channel, always writable */
3157 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3158 				       UAC3_BADD_FU_ID2, map->map);
3159 		/* Mono/Stereo volume channels, always writable */
3160 		build_feature_ctl_badd(mixer, p_chmask, UAC_FU_VOLUME,
3161 				       UAC3_BADD_FU_ID2, map->map);
3162 	}
3163 
3164 	/* Capture */
3165 	if (c_chmask) {
3166 		/* Master channel, always writable */
3167 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3168 				       UAC3_BADD_FU_ID5, map->map);
3169 		/* Mono/Stereo volume channels, always writable */
3170 		build_feature_ctl_badd(mixer, c_chmask, UAC_FU_VOLUME,
3171 				       UAC3_BADD_FU_ID5, map->map);
3172 	}
3173 
3174 	/* Side tone-mixing */
3175 	if (st_chmask) {
3176 		/* Master channel, always writable */
3177 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3178 				       UAC3_BADD_FU_ID7, map->map);
3179 		/* Mono volume channel, always writable */
3180 		build_feature_ctl_badd(mixer, 1, UAC_FU_VOLUME,
3181 				       UAC3_BADD_FU_ID7, map->map);
3182 	}
3183 
3184 	/* Insertion Control */
3185 	if (f->subclass == UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER) {
3186 		struct usb_audio_term iterm, oterm;
3187 
3188 		/* Input Term - Insertion control */
3189 		memset(&iterm, 0, sizeof(iterm));
3190 		iterm.id = UAC3_BADD_IT_ID4;
3191 		iterm.type = UAC_BIDIR_TERMINAL_HEADSET;
3192 		build_connector_control(mixer, map->map, &iterm, true);
3193 
3194 		/* Output Term - Insertion control */
3195 		memset(&oterm, 0, sizeof(oterm));
3196 		oterm.id = UAC3_BADD_OT_ID3;
3197 		oterm.type = UAC_BIDIR_TERMINAL_HEADSET;
3198 		build_connector_control(mixer, map->map, &oterm, false);
3199 	}
3200 
3201 	return 0;
3202 }
3203 
3204 /*
3205  * create mixer controls
3206  *
3207  * walk through all UAC_OUTPUT_TERMINAL descriptors to search for mixers
3208  */
3209 static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
3210 {
3211 	struct mixer_build state;
3212 	int err;
3213 	const struct usbmix_ctl_map *map;
3214 	void *p;
3215 
3216 	memset(&state, 0, sizeof(state));
3217 	state.chip = mixer->chip;
3218 	state.mixer = mixer;
3219 	state.buffer = mixer->hostif->extra;
3220 	state.buflen = mixer->hostif->extralen;
3221 
3222 	/* check the mapping table */
3223 	for (map = usbmix_ctl_maps; map->id; map++) {
3224 		if (map->id == state.chip->usb_id) {
3225 			state.map = map->map;
3226 			state.selector_map = map->selector_map;
3227 			mixer->connector_map = map->connector_map;
3228 			break;
3229 		}
3230 	}
3231 
3232 	p = NULL;
3233 	while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
3234 					    mixer->hostif->extralen,
3235 					    p, UAC_OUTPUT_TERMINAL)) != NULL) {
3236 		if (!snd_usb_validate_audio_desc(p, mixer->protocol))
3237 			continue; /* skip invalid descriptor */
3238 
3239 		if (mixer->protocol == UAC_VERSION_1) {
3240 			struct uac1_output_terminal_descriptor *desc = p;
3241 
3242 			/* mark terminal ID as visited */
3243 			set_bit(desc->bTerminalID, state.unitbitmap);
3244 			state.oterm.id = desc->bTerminalID;
3245 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3246 			state.oterm.name = desc->iTerminal;
3247 			err = parse_audio_unit(&state, desc->bSourceID);
3248 			if (err < 0 && err != -EINVAL)
3249 				return err;
3250 		} else if (mixer->protocol == UAC_VERSION_2) {
3251 			struct uac2_output_terminal_descriptor *desc = p;
3252 
3253 			/* mark terminal ID as visited */
3254 			set_bit(desc->bTerminalID, state.unitbitmap);
3255 			state.oterm.id = desc->bTerminalID;
3256 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3257 			state.oterm.name = desc->iTerminal;
3258 			err = parse_audio_unit(&state, desc->bSourceID);
3259 			if (err < 0 && err != -EINVAL)
3260 				return err;
3261 
3262 			/*
3263 			 * For UAC2, use the same approach to also add the
3264 			 * clock selectors
3265 			 */
3266 			err = parse_audio_unit(&state, desc->bCSourceID);
3267 			if (err < 0 && err != -EINVAL)
3268 				return err;
3269 
3270 			if ((state.oterm.type & 0xff00) != 0x0100 &&
3271 			    uac_v2v3_control_is_readable(le16_to_cpu(desc->bmControls),
3272 							 UAC2_TE_CONNECTOR)) {
3273 				build_connector_control(state.mixer, state.map,
3274 							&state.oterm, false);
3275 			}
3276 		} else {  /* UAC_VERSION_3 */
3277 			struct uac3_output_terminal_descriptor *desc = p;
3278 
3279 			/* mark terminal ID as visited */
3280 			set_bit(desc->bTerminalID, state.unitbitmap);
3281 			state.oterm.id = desc->bTerminalID;
3282 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3283 			state.oterm.name = le16_to_cpu(desc->wTerminalDescrStr);
3284 			err = parse_audio_unit(&state, desc->bSourceID);
3285 			if (err < 0 && err != -EINVAL)
3286 				return err;
3287 
3288 			/*
3289 			 * For UAC3, use the same approach to also add the
3290 			 * clock selectors
3291 			 */
3292 			err = parse_audio_unit(&state, desc->bCSourceID);
3293 			if (err < 0 && err != -EINVAL)
3294 				return err;
3295 
3296 			if ((state.oterm.type & 0xff00) != 0x0100 &&
3297 			    uac_v2v3_control_is_readable(le32_to_cpu(desc->bmControls),
3298 							 UAC3_TE_INSERTION)) {
3299 				build_connector_control(state.mixer, state.map,
3300 							&state.oterm, false);
3301 			}
3302 		}
3303 	}
3304 
3305 	return 0;
3306 }
3307 
3308 static int delegate_notify(struct usb_mixer_interface *mixer, int unitid,
3309 			   u8 *control, u8 *channel)
3310 {
3311 	const struct usbmix_connector_map *map = mixer->connector_map;
3312 
3313 	if (!map)
3314 		return unitid;
3315 
3316 	for (; map->id; map++) {
3317 		if (map->id == unitid) {
3318 			if (control && map->control)
3319 				*control = map->control;
3320 			if (channel && map->channel)
3321 				*channel = map->channel;
3322 			return map->delegated_id;
3323 		}
3324 	}
3325 	return unitid;
3326 }
3327 
3328 void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
3329 {
3330 	struct usb_mixer_elem_list *list;
3331 
3332 	unitid = delegate_notify(mixer, unitid, NULL, NULL);
3333 
3334 	for_each_mixer_elem(list, mixer, unitid) {
3335 		struct usb_mixer_elem_info *info;
3336 
3337 		if (!list->is_std_info)
3338 			continue;
3339 		info = mixer_elem_list_to_info(list);
3340 		/* invalidate cache, so the value is read from the device */
3341 		info->cached = 0;
3342 		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3343 			       &list->kctl->id);
3344 	}
3345 }
3346 
3347 static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
3348 				    struct usb_mixer_elem_list *list)
3349 {
3350 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3351 	static const char * const val_types[] = {
3352 		[USB_MIXER_BOOLEAN] = "BOOLEAN",
3353 		[USB_MIXER_INV_BOOLEAN] = "INV_BOOLEAN",
3354 		[USB_MIXER_S8] = "S8",
3355 		[USB_MIXER_U8] = "U8",
3356 		[USB_MIXER_S16] = "S16",
3357 		[USB_MIXER_U16] = "U16",
3358 		[USB_MIXER_S32] = "S32",
3359 		[USB_MIXER_U32] = "U32",
3360 		[USB_MIXER_BESPOKEN] = "BESPOKEN",
3361 	};
3362 	snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
3363 			    "channels=%i, type=\"%s\"\n", cval->head.id,
3364 			    cval->control, cval->cmask, cval->channels,
3365 			    val_types[cval->val_type]);
3366 	snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
3367 			    cval->min, cval->max, cval->dBmin, cval->dBmax);
3368 }
3369 
3370 static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
3371 				    struct snd_info_buffer *buffer)
3372 {
3373 	struct snd_usb_audio *chip = entry->private_data;
3374 	struct usb_mixer_interface *mixer;
3375 	struct usb_mixer_elem_list *list;
3376 	int unitid;
3377 
3378 	list_for_each_entry(mixer, &chip->mixer_list, list) {
3379 		snd_iprintf(buffer,
3380 			"USB Mixer: usb_id=0x%08x, ctrlif=%i, ctlerr=%i\n",
3381 				chip->usb_id, mixer_ctrl_intf(mixer),
3382 				mixer->ignore_ctl_error);
3383 		snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
3384 		for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
3385 			for_each_mixer_elem(list, mixer, unitid) {
3386 				snd_iprintf(buffer, "  Unit: %i\n", list->id);
3387 				if (list->kctl)
3388 					snd_iprintf(buffer,
3389 						    "    Control: name=\"%s\", index=%i\n",
3390 						    list->kctl->id.name,
3391 						    list->kctl->id.index);
3392 				if (list->dump)
3393 					list->dump(buffer, list);
3394 			}
3395 		}
3396 	}
3397 }
3398 
3399 static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
3400 				       int attribute, int value, int index)
3401 {
3402 	struct usb_mixer_elem_list *list;
3403 	__u8 unitid = (index >> 8) & 0xff;
3404 	__u8 control = (value >> 8) & 0xff;
3405 	__u8 channel = value & 0xff;
3406 	unsigned int count = 0;
3407 
3408 	if (channel >= MAX_CHANNELS) {
3409 		usb_audio_dbg(mixer->chip,
3410 			"%s(): bogus channel number %d\n",
3411 			__func__, channel);
3412 		return;
3413 	}
3414 
3415 	unitid = delegate_notify(mixer, unitid, &control, &channel);
3416 
3417 	for_each_mixer_elem(list, mixer, unitid)
3418 		count++;
3419 
3420 	if (count == 0)
3421 		return;
3422 
3423 	for_each_mixer_elem(list, mixer, unitid) {
3424 		struct usb_mixer_elem_info *info;
3425 
3426 		if (!list->kctl)
3427 			continue;
3428 		if (!list->is_std_info)
3429 			continue;
3430 
3431 		info = mixer_elem_list_to_info(list);
3432 		if (count > 1 && info->control != control)
3433 			continue;
3434 
3435 		switch (attribute) {
3436 		case UAC2_CS_CUR:
3437 			/* invalidate cache, so the value is read from the device */
3438 			if (channel)
3439 				info->cached &= ~(1 << channel);
3440 			else /* master channel */
3441 				info->cached = 0;
3442 
3443 			snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3444 				       &info->head.kctl->id);
3445 			break;
3446 
3447 		case UAC2_CS_RANGE:
3448 			/* TODO */
3449 			break;
3450 
3451 		case UAC2_CS_MEM:
3452 			/* TODO */
3453 			break;
3454 
3455 		default:
3456 			usb_audio_dbg(mixer->chip,
3457 				"unknown attribute %d in interrupt\n",
3458 				attribute);
3459 			break;
3460 		} /* switch */
3461 	}
3462 }
3463 
3464 static void snd_usb_mixer_interrupt(struct urb *urb)
3465 {
3466 	struct usb_mixer_interface *mixer = urb->context;
3467 	int len = urb->actual_length;
3468 	int ustatus = urb->status;
3469 
3470 	if (ustatus != 0)
3471 		goto requeue;
3472 
3473 	if (mixer->protocol == UAC_VERSION_1) {
3474 		struct uac1_status_word *status;
3475 
3476 		for (status = urb->transfer_buffer;
3477 		     len >= sizeof(*status);
3478 		     len -= sizeof(*status), status++) {
3479 			dev_dbg(&urb->dev->dev, "status interrupt: %02x %02x\n",
3480 						status->bStatusType,
3481 						status->bOriginator);
3482 
3483 			/* ignore any notifications not from the control interface */
3484 			if ((status->bStatusType & UAC1_STATUS_TYPE_ORIG_MASK) !=
3485 				UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF)
3486 				continue;
3487 
3488 			if (status->bStatusType & UAC1_STATUS_TYPE_MEM_CHANGED)
3489 				snd_usb_mixer_rc_memory_change(mixer, status->bOriginator);
3490 			else
3491 				snd_usb_mixer_notify_id(mixer, status->bOriginator);
3492 		}
3493 	} else { /* UAC_VERSION_2 */
3494 		struct uac2_interrupt_data_msg *msg;
3495 
3496 		for (msg = urb->transfer_buffer;
3497 		     len >= sizeof(*msg);
3498 		     len -= sizeof(*msg), msg++) {
3499 			/* drop vendor specific and endpoint requests */
3500 			if ((msg->bInfo & UAC2_INTERRUPT_DATA_MSG_VENDOR) ||
3501 			    (msg->bInfo & UAC2_INTERRUPT_DATA_MSG_EP))
3502 				continue;
3503 
3504 			snd_usb_mixer_interrupt_v2(mixer, msg->bAttribute,
3505 						   le16_to_cpu(msg->wValue),
3506 						   le16_to_cpu(msg->wIndex));
3507 		}
3508 	}
3509 
3510 requeue:
3511 	if (ustatus != -ENOENT &&
3512 	    ustatus != -ECONNRESET &&
3513 	    ustatus != -ESHUTDOWN) {
3514 		urb->dev = mixer->chip->dev;
3515 		usb_submit_urb(urb, GFP_ATOMIC);
3516 	}
3517 }
3518 
3519 /* create the handler for the optional status interrupt endpoint */
3520 static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
3521 {
3522 	struct usb_endpoint_descriptor *ep;
3523 	void *transfer_buffer;
3524 	int buffer_length;
3525 	unsigned int epnum;
3526 
3527 	/* we need one interrupt input endpoint */
3528 	if (get_iface_desc(mixer->hostif)->bNumEndpoints < 1)
3529 		return 0;
3530 	ep = get_endpoint(mixer->hostif, 0);
3531 	if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_int(ep))
3532 		return 0;
3533 
3534 	epnum = usb_endpoint_num(ep);
3535 	buffer_length = le16_to_cpu(ep->wMaxPacketSize);
3536 	transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
3537 	if (!transfer_buffer)
3538 		return -ENOMEM;
3539 	mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
3540 	if (!mixer->urb) {
3541 		kfree(transfer_buffer);
3542 		return -ENOMEM;
3543 	}
3544 	usb_fill_int_urb(mixer->urb, mixer->chip->dev,
3545 			 usb_rcvintpipe(mixer->chip->dev, epnum),
3546 			 transfer_buffer, buffer_length,
3547 			 snd_usb_mixer_interrupt, mixer, ep->bInterval);
3548 	usb_submit_urb(mixer->urb, GFP_KERNEL);
3549 	return 0;
3550 }
3551 
3552 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif)
3553 {
3554 	static const struct snd_device_ops dev_ops = {
3555 		.dev_free = snd_usb_mixer_dev_free
3556 	};
3557 	struct usb_mixer_interface *mixer;
3558 	int err;
3559 
3560 	strcpy(chip->card->mixername, "USB Mixer");
3561 
3562 	mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
3563 	if (!mixer)
3564 		return -ENOMEM;
3565 	mixer->chip = chip;
3566 	mixer->ignore_ctl_error = !!(chip->quirk_flags & QUIRK_FLAG_IGNORE_CTL_ERROR);
3567 	mixer->id_elems = kcalloc(MAX_ID_ELEMS, sizeof(*mixer->id_elems),
3568 				  GFP_KERNEL);
3569 	if (!mixer->id_elems) {
3570 		kfree(mixer);
3571 		return -ENOMEM;
3572 	}
3573 
3574 	mixer->hostif = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
3575 	switch (get_iface_desc(mixer->hostif)->bInterfaceProtocol) {
3576 	case UAC_VERSION_1:
3577 	default:
3578 		mixer->protocol = UAC_VERSION_1;
3579 		break;
3580 	case UAC_VERSION_2:
3581 		mixer->protocol = UAC_VERSION_2;
3582 		break;
3583 	case UAC_VERSION_3:
3584 		mixer->protocol = UAC_VERSION_3;
3585 		break;
3586 	}
3587 
3588 	if (mixer->protocol == UAC_VERSION_3 &&
3589 			chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
3590 		err = snd_usb_mixer_controls_badd(mixer, ctrlif);
3591 		if (err < 0)
3592 			goto _error;
3593 	} else {
3594 		err = snd_usb_mixer_controls(mixer);
3595 		if (err < 0)
3596 			goto _error;
3597 	}
3598 
3599 	err = snd_usb_mixer_status_create(mixer);
3600 	if (err < 0)
3601 		goto _error;
3602 
3603 	err = snd_usb_mixer_apply_create_quirk(mixer);
3604 	if (err < 0)
3605 		goto _error;
3606 
3607 	err = snd_device_new(chip->card, SNDRV_DEV_CODEC, mixer, &dev_ops);
3608 	if (err < 0)
3609 		goto _error;
3610 
3611 	if (list_empty(&chip->mixer_list))
3612 		snd_card_ro_proc_new(chip->card, "usbmixer", chip,
3613 				     snd_usb_mixer_proc_read);
3614 
3615 	list_add(&mixer->list, &chip->mixer_list);
3616 	return 0;
3617 
3618 _error:
3619 	snd_usb_mixer_free(mixer);
3620 	return err;
3621 }
3622 
3623 void snd_usb_mixer_disconnect(struct usb_mixer_interface *mixer)
3624 {
3625 	if (mixer->disconnected)
3626 		return;
3627 	if (mixer->urb)
3628 		usb_kill_urb(mixer->urb);
3629 	if (mixer->rc_urb)
3630 		usb_kill_urb(mixer->rc_urb);
3631 	if (mixer->private_free)
3632 		mixer->private_free(mixer);
3633 	mixer->disconnected = true;
3634 }
3635 
3636 /* stop any bus activity of a mixer */
3637 static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
3638 {
3639 	usb_kill_urb(mixer->urb);
3640 	usb_kill_urb(mixer->rc_urb);
3641 }
3642 
3643 static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
3644 {
3645 	int err;
3646 
3647 	if (mixer->urb) {
3648 		err = usb_submit_urb(mixer->urb, GFP_NOIO);
3649 		if (err < 0)
3650 			return err;
3651 	}
3652 
3653 	return 0;
3654 }
3655 
3656 int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
3657 {
3658 	snd_usb_mixer_inactivate(mixer);
3659 	if (mixer->private_suspend)
3660 		mixer->private_suspend(mixer);
3661 	return 0;
3662 }
3663 
3664 static int restore_mixer_value(struct usb_mixer_elem_list *list)
3665 {
3666 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3667 	int c, err, idx;
3668 
3669 	if (cval->val_type == USB_MIXER_BESPOKEN)
3670 		return 0;
3671 
3672 	if (cval->cmask) {
3673 		idx = 0;
3674 		for (c = 0; c < MAX_CHANNELS; c++) {
3675 			if (!(cval->cmask & (1 << c)))
3676 				continue;
3677 			if (cval->cached & (1 << (c + 1))) {
3678 				err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
3679 							cval->cache_val[idx]);
3680 				if (err < 0)
3681 					break;
3682 			}
3683 			idx++;
3684 		}
3685 	} else {
3686 		/* master */
3687 		if (cval->cached)
3688 			snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
3689 	}
3690 
3691 	return 0;
3692 }
3693 
3694 int snd_usb_mixer_resume(struct usb_mixer_interface *mixer)
3695 {
3696 	struct usb_mixer_elem_list *list;
3697 	int id, err;
3698 
3699 	/* restore cached mixer values */
3700 	for (id = 0; id < MAX_ID_ELEMS; id++) {
3701 		for_each_mixer_elem(list, mixer, id) {
3702 			if (list->resume) {
3703 				err = list->resume(list);
3704 				if (err < 0)
3705 					return err;
3706 			}
3707 		}
3708 	}
3709 
3710 	snd_usb_mixer_resume_quirk(mixer);
3711 
3712 	return snd_usb_mixer_activate(mixer);
3713 }
3714 
3715 void snd_usb_mixer_elem_init_std(struct usb_mixer_elem_list *list,
3716 				 struct usb_mixer_interface *mixer,
3717 				 int unitid)
3718 {
3719 	list->mixer = mixer;
3720 	list->id = unitid;
3721 	list->dump = snd_usb_mixer_dump_cval;
3722 	list->resume = restore_mixer_value;
3723 }
3724