xref: /openbmc/linux/sound/usb/mixer.c (revision b830f94f)
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 	struct usb_audio_term oterm;
72 	const struct usbmix_name_map *map;
73 	const struct usbmix_selector_map *selector_map;
74 };
75 
76 /*E-mu 0202/0404/0204 eXtension Unit(XU) control*/
77 enum {
78 	USB_XU_CLOCK_RATE 		= 0xe301,
79 	USB_XU_CLOCK_SOURCE		= 0xe302,
80 	USB_XU_DIGITAL_IO_STATUS	= 0xe303,
81 	USB_XU_DEVICE_OPTIONS		= 0xe304,
82 	USB_XU_DIRECT_MONITORING	= 0xe305,
83 	USB_XU_METERING			= 0xe306
84 };
85 enum {
86 	USB_XU_CLOCK_SOURCE_SELECTOR = 0x02,	/* clock source*/
87 	USB_XU_CLOCK_RATE_SELECTOR = 0x03,	/* clock rate */
88 	USB_XU_DIGITAL_FORMAT_SELECTOR = 0x01,	/* the spdif format */
89 	USB_XU_SOFT_LIMIT_SELECTOR = 0x03	/* soft limiter */
90 };
91 
92 /*
93  * manual mapping of mixer names
94  * if the mixer topology is too complicated and the parsed names are
95  * ambiguous, add the entries in usbmixer_maps.c.
96  */
97 #include "mixer_maps.c"
98 
99 static const struct usbmix_name_map *
100 find_map(const struct usbmix_name_map *p, int unitid, int control)
101 {
102 	if (!p)
103 		return NULL;
104 
105 	for (; p->id; p++) {
106 		if (p->id == unitid &&
107 		    (!control || !p->control || control == p->control))
108 			return p;
109 	}
110 	return NULL;
111 }
112 
113 /* get the mapped name if the unit matches */
114 static int
115 check_mapped_name(const struct usbmix_name_map *p, char *buf, int buflen)
116 {
117 	if (!p || !p->name)
118 		return 0;
119 
120 	buflen--;
121 	return strlcpy(buf, p->name, buflen);
122 }
123 
124 /* ignore the error value if ignore_ctl_error flag is set */
125 #define filter_error(cval, err) \
126 	((cval)->head.mixer->ignore_ctl_error ? 0 : (err))
127 
128 /* check whether the control should be ignored */
129 static inline int
130 check_ignored_ctl(const struct usbmix_name_map *p)
131 {
132 	if (!p || p->name || p->dB)
133 		return 0;
134 	return 1;
135 }
136 
137 /* dB mapping */
138 static inline void check_mapped_dB(const struct usbmix_name_map *p,
139 				   struct usb_mixer_elem_info *cval)
140 {
141 	if (p && p->dB) {
142 		cval->dBmin = p->dB->min;
143 		cval->dBmax = p->dB->max;
144 		cval->initialized = 1;
145 	}
146 }
147 
148 /* get the mapped selector source name */
149 static int check_mapped_selector_name(struct mixer_build *state, int unitid,
150 				      int index, char *buf, int buflen)
151 {
152 	const struct usbmix_selector_map *p;
153 
154 	if (!state->selector_map)
155 		return 0;
156 	for (p = state->selector_map; p->id; p++) {
157 		if (p->id == unitid && index < p->count)
158 			return strlcpy(buf, p->names[index], buflen);
159 	}
160 	return 0;
161 }
162 
163 /*
164  * find an audio control unit with the given unit id
165  */
166 static void *find_audio_control_unit(struct mixer_build *state,
167 				     unsigned char unit)
168 {
169 	/* we just parse the header */
170 	struct uac_feature_unit_descriptor *hdr = NULL;
171 
172 	while ((hdr = snd_usb_find_desc(state->buffer, state->buflen, hdr,
173 					USB_DT_CS_INTERFACE)) != NULL) {
174 		if (hdr->bLength >= 4 &&
175 		    hdr->bDescriptorSubtype >= UAC_INPUT_TERMINAL &&
176 		    hdr->bDescriptorSubtype <= UAC3_SAMPLE_RATE_CONVERTER &&
177 		    hdr->bUnitID == unit)
178 			return hdr;
179 	}
180 
181 	return NULL;
182 }
183 
184 /*
185  * copy a string with the given id
186  */
187 static int snd_usb_copy_string_desc(struct snd_usb_audio *chip,
188 				    int index, char *buf, int maxlen)
189 {
190 	int len = usb_string(chip->dev, index, buf, maxlen - 1);
191 
192 	if (len < 0)
193 		return 0;
194 
195 	buf[len] = 0;
196 	return len;
197 }
198 
199 /*
200  * convert from the byte/word on usb descriptor to the zero-based integer
201  */
202 static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
203 {
204 	switch (cval->val_type) {
205 	case USB_MIXER_BOOLEAN:
206 		return !!val;
207 	case USB_MIXER_INV_BOOLEAN:
208 		return !val;
209 	case USB_MIXER_U8:
210 		val &= 0xff;
211 		break;
212 	case USB_MIXER_S8:
213 		val &= 0xff;
214 		if (val >= 0x80)
215 			val -= 0x100;
216 		break;
217 	case USB_MIXER_U16:
218 		val &= 0xffff;
219 		break;
220 	case USB_MIXER_S16:
221 		val &= 0xffff;
222 		if (val >= 0x8000)
223 			val -= 0x10000;
224 		break;
225 	}
226 	return val;
227 }
228 
229 /*
230  * convert from the zero-based int to the byte/word for usb descriptor
231  */
232 static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
233 {
234 	switch (cval->val_type) {
235 	case USB_MIXER_BOOLEAN:
236 		return !!val;
237 	case USB_MIXER_INV_BOOLEAN:
238 		return !val;
239 	case USB_MIXER_S8:
240 	case USB_MIXER_U8:
241 		return val & 0xff;
242 	case USB_MIXER_S16:
243 	case USB_MIXER_U16:
244 		return val & 0xffff;
245 	}
246 	return 0; /* not reached */
247 }
248 
249 static int get_relative_value(struct usb_mixer_elem_info *cval, int val)
250 {
251 	if (!cval->res)
252 		cval->res = 1;
253 	if (val < cval->min)
254 		return 0;
255 	else if (val >= cval->max)
256 		return (cval->max - cval->min + cval->res - 1) / cval->res;
257 	else
258 		return (val - cval->min) / cval->res;
259 }
260 
261 static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
262 {
263 	if (val < 0)
264 		return cval->min;
265 	if (!cval->res)
266 		cval->res = 1;
267 	val *= cval->res;
268 	val += cval->min;
269 	if (val > cval->max)
270 		return cval->max;
271 	return val;
272 }
273 
274 static int uac2_ctl_value_size(int val_type)
275 {
276 	switch (val_type) {
277 	case USB_MIXER_S32:
278 	case USB_MIXER_U32:
279 		return 4;
280 	case USB_MIXER_S16:
281 	case USB_MIXER_U16:
282 		return 2;
283 	default:
284 		return 1;
285 	}
286 	return 0; /* unreachable */
287 }
288 
289 
290 /*
291  * retrieve a mixer value
292  */
293 
294 static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request,
295 			    int validx, int *value_ret)
296 {
297 	struct snd_usb_audio *chip = cval->head.mixer->chip;
298 	unsigned char buf[2];
299 	int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
300 	int timeout = 10;
301 	int idx = 0, err;
302 
303 	err = snd_usb_lock_shutdown(chip);
304 	if (err < 0)
305 		return -EIO;
306 
307 	while (timeout-- > 0) {
308 		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
309 		err = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
310 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
311 				      validx, idx, buf, val_len);
312 		if (err >= val_len) {
313 			*value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
314 			err = 0;
315 			goto out;
316 		} else if (err == -ETIMEDOUT) {
317 			goto out;
318 		}
319 	}
320 	usb_audio_dbg(chip,
321 		"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
322 		request, validx, idx, cval->val_type);
323 	err = -EINVAL;
324 
325  out:
326 	snd_usb_unlock_shutdown(chip);
327 	return err;
328 }
329 
330 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
331 			    int validx, int *value_ret)
332 {
333 	struct snd_usb_audio *chip = cval->head.mixer->chip;
334 	/* enough space for one range */
335 	unsigned char buf[sizeof(__u16) + 3 * sizeof(__u32)];
336 	unsigned char *val;
337 	int idx = 0, ret, val_size, size;
338 	__u8 bRequest;
339 
340 	val_size = uac2_ctl_value_size(cval->val_type);
341 
342 	if (request == UAC_GET_CUR) {
343 		bRequest = UAC2_CS_CUR;
344 		size = val_size;
345 	} else {
346 		bRequest = UAC2_CS_RANGE;
347 		size = sizeof(__u16) + 3 * val_size;
348 	}
349 
350 	memset(buf, 0, sizeof(buf));
351 
352 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
353 	if (ret)
354 		goto error;
355 
356 	idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
357 	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
358 			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
359 			      validx, idx, buf, size);
360 	snd_usb_unlock_shutdown(chip);
361 
362 	if (ret < 0) {
363 error:
364 		usb_audio_err(chip,
365 			"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
366 			request, validx, idx, cval->val_type);
367 		return ret;
368 	}
369 
370 	/* FIXME: how should we handle multiple triplets here? */
371 
372 	switch (request) {
373 	case UAC_GET_CUR:
374 		val = buf;
375 		break;
376 	case UAC_GET_MIN:
377 		val = buf + sizeof(__u16);
378 		break;
379 	case UAC_GET_MAX:
380 		val = buf + sizeof(__u16) + val_size;
381 		break;
382 	case UAC_GET_RES:
383 		val = buf + sizeof(__u16) + val_size * 2;
384 		break;
385 	default:
386 		return -EINVAL;
387 	}
388 
389 	*value_ret = convert_signed_value(cval,
390 					  snd_usb_combine_bytes(val, val_size));
391 
392 	return 0;
393 }
394 
395 static int get_ctl_value(struct usb_mixer_elem_info *cval, int request,
396 			 int validx, int *value_ret)
397 {
398 	validx += cval->idx_off;
399 
400 	return (cval->head.mixer->protocol == UAC_VERSION_1) ?
401 		get_ctl_value_v1(cval, request, validx, value_ret) :
402 		get_ctl_value_v2(cval, request, validx, value_ret);
403 }
404 
405 static int get_cur_ctl_value(struct usb_mixer_elem_info *cval,
406 			     int validx, int *value)
407 {
408 	return get_ctl_value(cval, UAC_GET_CUR, validx, value);
409 }
410 
411 /* channel = 0: master, 1 = first channel */
412 static inline int get_cur_mix_raw(struct usb_mixer_elem_info *cval,
413 				  int channel, int *value)
414 {
415 	return get_ctl_value(cval, UAC_GET_CUR,
416 			     (cval->control << 8) | channel,
417 			     value);
418 }
419 
420 int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
421 			     int channel, int index, int *value)
422 {
423 	int err;
424 
425 	if (cval->cached & (1 << channel)) {
426 		*value = cval->cache_val[index];
427 		return 0;
428 	}
429 	err = get_cur_mix_raw(cval, channel, value);
430 	if (err < 0) {
431 		if (!cval->head.mixer->ignore_ctl_error)
432 			usb_audio_dbg(cval->head.mixer->chip,
433 				"cannot get current value for control %d ch %d: err = %d\n",
434 				      cval->control, channel, err);
435 		return err;
436 	}
437 	cval->cached |= 1 << channel;
438 	cval->cache_val[index] = *value;
439 	return 0;
440 }
441 
442 /*
443  * set a mixer value
444  */
445 
446 int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
447 				int request, int validx, int value_set)
448 {
449 	struct snd_usb_audio *chip = cval->head.mixer->chip;
450 	unsigned char buf[4];
451 	int idx = 0, val_len, err, timeout = 10;
452 
453 	validx += cval->idx_off;
454 
455 
456 	if (cval->head.mixer->protocol == UAC_VERSION_1) {
457 		val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
458 	} else { /* UAC_VERSION_2/3 */
459 		val_len = uac2_ctl_value_size(cval->val_type);
460 
461 		/* FIXME */
462 		if (request != UAC_SET_CUR) {
463 			usb_audio_dbg(chip, "RANGE setting not yet supported\n");
464 			return -EINVAL;
465 		}
466 
467 		request = UAC2_CS_CUR;
468 	}
469 
470 	value_set = convert_bytes_value(cval, value_set);
471 	buf[0] = value_set & 0xff;
472 	buf[1] = (value_set >> 8) & 0xff;
473 	buf[2] = (value_set >> 16) & 0xff;
474 	buf[3] = (value_set >> 24) & 0xff;
475 
476 	err = snd_usb_lock_shutdown(chip);
477 	if (err < 0)
478 		return -EIO;
479 
480 	while (timeout-- > 0) {
481 		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
482 		err = snd_usb_ctl_msg(chip->dev,
483 				      usb_sndctrlpipe(chip->dev, 0), request,
484 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
485 				      validx, idx, buf, val_len);
486 		if (err >= 0) {
487 			err = 0;
488 			goto out;
489 		} else if (err == -ETIMEDOUT) {
490 			goto out;
491 		}
492 	}
493 	usb_audio_dbg(chip, "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
494 		      request, validx, idx, cval->val_type, buf[0], buf[1]);
495 	err = -EINVAL;
496 
497  out:
498 	snd_usb_unlock_shutdown(chip);
499 	return err;
500 }
501 
502 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval,
503 			     int validx, int value)
504 {
505 	return snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, validx, value);
506 }
507 
508 int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
509 			     int index, int value)
510 {
511 	int err;
512 	unsigned int read_only = (channel == 0) ?
513 		cval->master_readonly :
514 		cval->ch_readonly & (1 << (channel - 1));
515 
516 	if (read_only) {
517 		usb_audio_dbg(cval->head.mixer->chip,
518 			      "%s(): channel %d of control %d is read_only\n",
519 			    __func__, channel, cval->control);
520 		return 0;
521 	}
522 
523 	err = snd_usb_mixer_set_ctl_value(cval,
524 					  UAC_SET_CUR, (cval->control << 8) | channel,
525 					  value);
526 	if (err < 0)
527 		return err;
528 	cval->cached |= 1 << channel;
529 	cval->cache_val[index] = value;
530 	return 0;
531 }
532 
533 /*
534  * TLV callback for mixer volume controls
535  */
536 int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
537 			 unsigned int size, unsigned int __user *_tlv)
538 {
539 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
540 	DECLARE_TLV_DB_MINMAX(scale, 0, 0);
541 
542 	if (size < sizeof(scale))
543 		return -ENOMEM;
544 	if (cval->min_mute)
545 		scale[0] = SNDRV_CTL_TLVT_DB_MINMAX_MUTE;
546 	scale[2] = cval->dBmin;
547 	scale[3] = cval->dBmax;
548 	if (copy_to_user(_tlv, scale, sizeof(scale)))
549 		return -EFAULT;
550 	return 0;
551 }
552 
553 /*
554  * parser routines begin here...
555  */
556 
557 static int parse_audio_unit(struct mixer_build *state, int unitid);
558 
559 
560 /*
561  * check if the input/output channel routing is enabled on the given bitmap.
562  * used for mixer unit parser
563  */
564 static int check_matrix_bitmap(unsigned char *bmap,
565 			       int ich, int och, int num_outs)
566 {
567 	int idx = ich * num_outs + och;
568 	return bmap[idx >> 3] & (0x80 >> (idx & 7));
569 }
570 
571 /*
572  * add an alsa control element
573  * search and increment the index until an empty slot is found.
574  *
575  * if failed, give up and free the control instance.
576  */
577 
578 int snd_usb_mixer_add_control(struct usb_mixer_elem_list *list,
579 			      struct snd_kcontrol *kctl)
580 {
581 	struct usb_mixer_interface *mixer = list->mixer;
582 	int err;
583 
584 	while (snd_ctl_find_id(mixer->chip->card, &kctl->id))
585 		kctl->id.index++;
586 	err = snd_ctl_add(mixer->chip->card, kctl);
587 	if (err < 0) {
588 		usb_audio_dbg(mixer->chip, "cannot add control (err = %d)\n",
589 			      err);
590 		return err;
591 	}
592 	list->kctl = kctl;
593 	list->next_id_elem = mixer->id_elems[list->id];
594 	mixer->id_elems[list->id] = list;
595 	return 0;
596 }
597 
598 /*
599  * get a terminal name string
600  */
601 
602 static struct iterm_name_combo {
603 	int type;
604 	char *name;
605 } iterm_names[] = {
606 	{ 0x0300, "Output" },
607 	{ 0x0301, "Speaker" },
608 	{ 0x0302, "Headphone" },
609 	{ 0x0303, "HMD Audio" },
610 	{ 0x0304, "Desktop Speaker" },
611 	{ 0x0305, "Room Speaker" },
612 	{ 0x0306, "Com Speaker" },
613 	{ 0x0307, "LFE" },
614 	{ 0x0600, "External In" },
615 	{ 0x0601, "Analog In" },
616 	{ 0x0602, "Digital In" },
617 	{ 0x0603, "Line" },
618 	{ 0x0604, "Legacy In" },
619 	{ 0x0605, "IEC958 In" },
620 	{ 0x0606, "1394 DA Stream" },
621 	{ 0x0607, "1394 DV Stream" },
622 	{ 0x0700, "Embedded" },
623 	{ 0x0701, "Noise Source" },
624 	{ 0x0702, "Equalization Noise" },
625 	{ 0x0703, "CD" },
626 	{ 0x0704, "DAT" },
627 	{ 0x0705, "DCC" },
628 	{ 0x0706, "MiniDisk" },
629 	{ 0x0707, "Analog Tape" },
630 	{ 0x0708, "Phonograph" },
631 	{ 0x0709, "VCR Audio" },
632 	{ 0x070a, "Video Disk Audio" },
633 	{ 0x070b, "DVD Audio" },
634 	{ 0x070c, "TV Tuner Audio" },
635 	{ 0x070d, "Satellite Rec Audio" },
636 	{ 0x070e, "Cable Tuner Audio" },
637 	{ 0x070f, "DSS Audio" },
638 	{ 0x0710, "Radio Receiver" },
639 	{ 0x0711, "Radio Transmitter" },
640 	{ 0x0712, "Multi-Track Recorder" },
641 	{ 0x0713, "Synthesizer" },
642 	{ 0 },
643 };
644 
645 static int get_term_name(struct snd_usb_audio *chip, struct usb_audio_term *iterm,
646 			 unsigned char *name, int maxlen, int term_only)
647 {
648 	struct iterm_name_combo *names;
649 	int len;
650 
651 	if (iterm->name) {
652 		len = snd_usb_copy_string_desc(chip, iterm->name,
653 						name, maxlen);
654 		if (len)
655 			return len;
656 	}
657 
658 	/* virtual type - not a real terminal */
659 	if (iterm->type >> 16) {
660 		if (term_only)
661 			return 0;
662 		switch (iterm->type >> 16) {
663 		case UAC3_SELECTOR_UNIT:
664 			strcpy(name, "Selector");
665 			return 8;
666 		case UAC3_PROCESSING_UNIT:
667 			strcpy(name, "Process Unit");
668 			return 12;
669 		case UAC3_EXTENSION_UNIT:
670 			strcpy(name, "Ext Unit");
671 			return 8;
672 		case UAC3_MIXER_UNIT:
673 			strcpy(name, "Mixer");
674 			return 5;
675 		default:
676 			return sprintf(name, "Unit %d", iterm->id);
677 		}
678 	}
679 
680 	switch (iterm->type & 0xff00) {
681 	case 0x0100:
682 		strcpy(name, "PCM");
683 		return 3;
684 	case 0x0200:
685 		strcpy(name, "Mic");
686 		return 3;
687 	case 0x0400:
688 		strcpy(name, "Headset");
689 		return 7;
690 	case 0x0500:
691 		strcpy(name, "Phone");
692 		return 5;
693 	}
694 
695 	for (names = iterm_names; names->type; names++) {
696 		if (names->type == iterm->type) {
697 			strcpy(name, names->name);
698 			return strlen(names->name);
699 		}
700 	}
701 
702 	return 0;
703 }
704 
705 /*
706  * Get logical cluster information for UAC3 devices.
707  */
708 static int get_cluster_channels_v3(struct mixer_build *state, unsigned int cluster_id)
709 {
710 	struct uac3_cluster_header_descriptor c_header;
711 	int err;
712 
713 	err = snd_usb_ctl_msg(state->chip->dev,
714 			usb_rcvctrlpipe(state->chip->dev, 0),
715 			UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
716 			USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
717 			cluster_id,
718 			snd_usb_ctrl_intf(state->chip),
719 			&c_header, sizeof(c_header));
720 	if (err < 0)
721 		goto error;
722 	if (err != sizeof(c_header)) {
723 		err = -EIO;
724 		goto error;
725 	}
726 
727 	return c_header.bNrChannels;
728 
729 error:
730 	usb_audio_err(state->chip, "cannot request logical cluster ID: %d (err: %d)\n", cluster_id, err);
731 	return err;
732 }
733 
734 /*
735  * Get number of channels for a Mixer Unit.
736  */
737 static int uac_mixer_unit_get_channels(struct mixer_build *state,
738 				       struct uac_mixer_unit_descriptor *desc)
739 {
740 	int mu_channels;
741 	void *c;
742 
743 	if (desc->bLength < sizeof(*desc))
744 		return -EINVAL;
745 	if (!desc->bNrInPins)
746 		return -EINVAL;
747 
748 	switch (state->mixer->protocol) {
749 	case UAC_VERSION_1:
750 	case UAC_VERSION_2:
751 	default:
752 		if (desc->bLength < sizeof(*desc) + desc->bNrInPins + 1)
753 			return 0; /* no bmControls -> skip */
754 		mu_channels = uac_mixer_unit_bNrChannels(desc);
755 		break;
756 	case UAC_VERSION_3:
757 		mu_channels = get_cluster_channels_v3(state,
758 				uac3_mixer_unit_wClusterDescrID(desc));
759 		break;
760 	}
761 
762 	if (!mu_channels)
763 		return 0;
764 
765 	c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
766 	if (c - (void *)desc + (mu_channels - 1) / 8 >= desc->bLength)
767 		return 0; /* no bmControls -> skip */
768 
769 	return mu_channels;
770 }
771 
772 /*
773  * parse the source unit recursively until it reaches to a terminal
774  * or a branched unit.
775  */
776 static int check_input_term(struct mixer_build *state, int id,
777 			    struct usb_audio_term *term)
778 {
779 	int protocol = state->mixer->protocol;
780 	int err;
781 	void *p1;
782 
783 	memset(term, 0, sizeof(*term));
784 	while ((p1 = find_audio_control_unit(state, id)) != NULL) {
785 		unsigned char *hdr = p1;
786 		term->id = id;
787 
788 		if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {
789 			switch (hdr[2]) {
790 			case UAC_INPUT_TERMINAL:
791 				if (protocol == UAC_VERSION_1) {
792 					struct uac_input_terminal_descriptor *d = p1;
793 
794 					term->type = le16_to_cpu(d->wTerminalType);
795 					term->channels = d->bNrChannels;
796 					term->chconfig = le16_to_cpu(d->wChannelConfig);
797 					term->name = d->iTerminal;
798 				} else { /* UAC_VERSION_2 */
799 					struct uac2_input_terminal_descriptor *d = p1;
800 
801 					/* call recursively to verify that the
802 					 * referenced clock entity is valid */
803 					err = check_input_term(state, d->bCSourceID, term);
804 					if (err < 0)
805 						return err;
806 
807 					/* save input term properties after recursion,
808 					 * to ensure they are not overriden by the
809 					 * recursion calls */
810 					term->id = id;
811 					term->type = le16_to_cpu(d->wTerminalType);
812 					term->channels = d->bNrChannels;
813 					term->chconfig = le32_to_cpu(d->bmChannelConfig);
814 					term->name = d->iTerminal;
815 				}
816 				return 0;
817 			case UAC_FEATURE_UNIT: {
818 				/* the header is the same for v1 and v2 */
819 				struct uac_feature_unit_descriptor *d = p1;
820 
821 				id = d->bSourceID;
822 				break; /* continue to parse */
823 			}
824 			case UAC_MIXER_UNIT: {
825 				struct uac_mixer_unit_descriptor *d = p1;
826 
827 				term->type = UAC3_MIXER_UNIT << 16; /* virtual type */
828 				term->channels = uac_mixer_unit_bNrChannels(d);
829 				term->chconfig = uac_mixer_unit_wChannelConfig(d, protocol);
830 				term->name = uac_mixer_unit_iMixer(d);
831 				return 0;
832 			}
833 			case UAC_SELECTOR_UNIT:
834 			case UAC2_CLOCK_SELECTOR: {
835 				struct uac_selector_unit_descriptor *d = p1;
836 				/* call recursively to retrieve the channel info */
837 				err = check_input_term(state, d->baSourceID[0], term);
838 				if (err < 0)
839 					return err;
840 				term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */
841 				term->id = id;
842 				term->name = uac_selector_unit_iSelector(d);
843 				return 0;
844 			}
845 			case UAC1_PROCESSING_UNIT:
846 			/* UAC2_EFFECT_UNIT */
847 				if (protocol == UAC_VERSION_1)
848 					term->type = UAC3_PROCESSING_UNIT << 16; /* virtual type */
849 				else /* UAC_VERSION_2 */
850 					term->type = UAC3_EFFECT_UNIT << 16; /* virtual type */
851 				/* fall through */
852 			case UAC1_EXTENSION_UNIT:
853 			/* UAC2_PROCESSING_UNIT_V2 */
854 				if (protocol == UAC_VERSION_1 && !term->type)
855 					term->type = UAC3_EXTENSION_UNIT << 16; /* virtual type */
856 				else if (protocol == UAC_VERSION_2 && !term->type)
857 					term->type = UAC3_PROCESSING_UNIT << 16; /* virtual type */
858 				/* fall through */
859 			case UAC2_EXTENSION_UNIT_V2: {
860 				struct uac_processing_unit_descriptor *d = p1;
861 
862 				if (protocol == UAC_VERSION_2 &&
863 					hdr[2] == UAC2_EFFECT_UNIT) {
864 					/* UAC2/UAC1 unit IDs overlap here in an
865 					 * uncompatible way. Ignore this unit for now.
866 					 */
867 					return 0;
868 				}
869 
870 				if (d->bNrInPins) {
871 					id = d->baSourceID[0];
872 					break; /* continue to parse */
873 				}
874 				if (!term->type)
875 					term->type = UAC3_EXTENSION_UNIT << 16; /* virtual type */
876 
877 				term->channels = uac_processing_unit_bNrChannels(d);
878 				term->chconfig = uac_processing_unit_wChannelConfig(d, protocol);
879 				term->name = uac_processing_unit_iProcessing(d, protocol);
880 				return 0;
881 			}
882 			case UAC2_CLOCK_SOURCE: {
883 				struct uac_clock_source_descriptor *d = p1;
884 
885 				term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
886 				term->id = id;
887 				term->name = d->iClockSource;
888 				return 0;
889 			}
890 			default:
891 				return -ENODEV;
892 			}
893 		} else { /* UAC_VERSION_3 */
894 			switch (hdr[2]) {
895 			case UAC_INPUT_TERMINAL: {
896 				struct uac3_input_terminal_descriptor *d = p1;
897 
898 				/* call recursively to verify that the
899 				 * referenced clock entity is valid */
900 				err = check_input_term(state, d->bCSourceID, term);
901 				if (err < 0)
902 					return err;
903 
904 				/* save input term properties after recursion,
905 				 * to ensure they are not overriden by the
906 				 * recursion calls */
907 				term->id = id;
908 				term->type = le16_to_cpu(d->wTerminalType);
909 
910 				err = get_cluster_channels_v3(state, le16_to_cpu(d->wClusterDescrID));
911 				if (err < 0)
912 					return err;
913 				term->channels = err;
914 
915 				/* REVISIT: UAC3 IT doesn't have channels cfg */
916 				term->chconfig = 0;
917 
918 				term->name = le16_to_cpu(d->wTerminalDescrStr);
919 				return 0;
920 			}
921 			case UAC3_FEATURE_UNIT: {
922 				struct uac3_feature_unit_descriptor *d = p1;
923 
924 				id = d->bSourceID;
925 				break; /* continue to parse */
926 			}
927 			case UAC3_CLOCK_SOURCE: {
928 				struct uac3_clock_source_descriptor *d = p1;
929 
930 				term->type = UAC3_CLOCK_SOURCE << 16; /* virtual type */
931 				term->id = id;
932 				term->name = le16_to_cpu(d->wClockSourceStr);
933 				return 0;
934 			}
935 			case UAC3_MIXER_UNIT: {
936 				struct uac_mixer_unit_descriptor *d = p1;
937 
938 				err = uac_mixer_unit_get_channels(state, d);
939 				if (err <= 0)
940 					return err;
941 
942 				term->channels = err;
943 				term->type = UAC3_MIXER_UNIT << 16; /* virtual type */
944 
945 				return 0;
946 			}
947 			case UAC3_SELECTOR_UNIT:
948 			case UAC3_CLOCK_SELECTOR: {
949 				struct uac_selector_unit_descriptor *d = p1;
950 				/* call recursively to retrieve the channel info */
951 				err = check_input_term(state, d->baSourceID[0], term);
952 				if (err < 0)
953 					return err;
954 				term->type = UAC3_SELECTOR_UNIT << 16; /* virtual type */
955 				term->id = id;
956 				term->name = 0; /* TODO: UAC3 Class-specific strings */
957 
958 				return 0;
959 			}
960 			case UAC3_PROCESSING_UNIT: {
961 				struct uac_processing_unit_descriptor *d = p1;
962 
963 				if (!d->bNrInPins)
964 					return -EINVAL;
965 
966 				/* call recursively to retrieve the channel info */
967 				err = check_input_term(state, d->baSourceID[0], term);
968 				if (err < 0)
969 					return err;
970 
971 				term->type = UAC3_PROCESSING_UNIT << 16; /* virtual type */
972 				term->id = id;
973 				term->name = 0; /* TODO: UAC3 Class-specific strings */
974 
975 				return 0;
976 			}
977 			default:
978 				return -ENODEV;
979 			}
980 		}
981 	}
982 	return -ENODEV;
983 }
984 
985 /*
986  * Feature Unit
987  */
988 
989 /* feature unit control information */
990 struct usb_feature_control_info {
991 	int control;
992 	const char *name;
993 	int type;	/* data type for uac1 */
994 	int type_uac2;	/* data type for uac2 if different from uac1, else -1 */
995 };
996 
997 static struct usb_feature_control_info audio_feature_info[] = {
998 	{ UAC_FU_MUTE,			"Mute",			USB_MIXER_INV_BOOLEAN, -1 },
999 	{ UAC_FU_VOLUME,		"Volume",		USB_MIXER_S16, -1 },
1000 	{ UAC_FU_BASS,			"Tone Control - Bass",	USB_MIXER_S8, -1 },
1001 	{ UAC_FU_MID,			"Tone Control - Mid",	USB_MIXER_S8, -1 },
1002 	{ UAC_FU_TREBLE,		"Tone Control - Treble", USB_MIXER_S8, -1 },
1003 	{ UAC_FU_GRAPHIC_EQUALIZER,	"Graphic Equalizer",	USB_MIXER_S8, -1 }, /* FIXME: not implemented yet */
1004 	{ UAC_FU_AUTOMATIC_GAIN,	"Auto Gain Control",	USB_MIXER_BOOLEAN, -1 },
1005 	{ UAC_FU_DELAY,			"Delay Control",	USB_MIXER_U16, USB_MIXER_U32 },
1006 	{ UAC_FU_BASS_BOOST,		"Bass Boost",		USB_MIXER_BOOLEAN, -1 },
1007 	{ UAC_FU_LOUDNESS,		"Loudness",		USB_MIXER_BOOLEAN, -1 },
1008 	/* UAC2 specific */
1009 	{ UAC2_FU_INPUT_GAIN,		"Input Gain Control",	USB_MIXER_S16, -1 },
1010 	{ UAC2_FU_INPUT_GAIN_PAD,	"Input Gain Pad Control", USB_MIXER_S16, -1 },
1011 	{ UAC2_FU_PHASE_INVERTER,	 "Phase Inverter Control", USB_MIXER_BOOLEAN, -1 },
1012 };
1013 
1014 /* private_free callback */
1015 void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
1016 {
1017 	kfree(kctl->private_data);
1018 	kctl->private_data = NULL;
1019 }
1020 
1021 /*
1022  * interface to ALSA control for feature/mixer units
1023  */
1024 
1025 /* volume control quirks */
1026 static void volume_control_quirks(struct usb_mixer_elem_info *cval,
1027 				  struct snd_kcontrol *kctl)
1028 {
1029 	struct snd_usb_audio *chip = cval->head.mixer->chip;
1030 	switch (chip->usb_id) {
1031 	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
1032 	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
1033 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
1034 			cval->min = 0x0000;
1035 			cval->max = 0xffff;
1036 			cval->res = 0x00e6;
1037 			break;
1038 		}
1039 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1040 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1041 			cval->min = 0x00;
1042 			cval->max = 0xff;
1043 			break;
1044 		}
1045 		if (strstr(kctl->id.name, "Effect Return") != NULL) {
1046 			cval->min = 0xb706;
1047 			cval->max = 0xff7b;
1048 			cval->res = 0x0073;
1049 			break;
1050 		}
1051 		if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
1052 			(strstr(kctl->id.name, "Effect Send") != NULL)) {
1053 			cval->min = 0xb5fb; /* -73 dB = 0xb6ff */
1054 			cval->max = 0xfcfe;
1055 			cval->res = 0x0073;
1056 		}
1057 		break;
1058 
1059 	case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */
1060 	case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
1061 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
1062 			usb_audio_info(chip,
1063 				       "set quirk for FTU Effect Duration\n");
1064 			cval->min = 0x0000;
1065 			cval->max = 0x7f00;
1066 			cval->res = 0x0100;
1067 			break;
1068 		}
1069 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1070 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1071 			usb_audio_info(chip,
1072 				       "set quirks for FTU Effect Feedback/Volume\n");
1073 			cval->min = 0x00;
1074 			cval->max = 0x7f;
1075 			break;
1076 		}
1077 		break;
1078 
1079 	case USB_ID(0x0d8c, 0x0103):
1080 		if (!strcmp(kctl->id.name, "PCM Playback Volume")) {
1081 			usb_audio_info(chip,
1082 				 "set volume quirk for CM102-A+/102S+\n");
1083 			cval->min = -256;
1084 		}
1085 		break;
1086 
1087 	case USB_ID(0x0471, 0x0101):
1088 	case USB_ID(0x0471, 0x0104):
1089 	case USB_ID(0x0471, 0x0105):
1090 	case USB_ID(0x0672, 0x1041):
1091 	/* quirk for UDA1321/N101.
1092 	 * note that detection between firmware 2.1.1.7 (N101)
1093 	 * and later 2.1.1.21 is not very clear from datasheets.
1094 	 * I hope that the min value is -15360 for newer firmware --jk
1095 	 */
1096 		if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
1097 		    cval->min == -15616) {
1098 			usb_audio_info(chip,
1099 				 "set volume quirk for UDA1321/N101 chip\n");
1100 			cval->max = -256;
1101 		}
1102 		break;
1103 
1104 	case USB_ID(0x046d, 0x09a4):
1105 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1106 			usb_audio_info(chip,
1107 				"set volume quirk for QuickCam E3500\n");
1108 			cval->min = 6080;
1109 			cval->max = 8768;
1110 			cval->res = 192;
1111 		}
1112 		break;
1113 
1114 	case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
1115 	case USB_ID(0x046d, 0x0808):
1116 	case USB_ID(0x046d, 0x0809):
1117 	case USB_ID(0x046d, 0x0819): /* Logitech Webcam C210 */
1118 	case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
1119 	case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
1120 	case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
1121 	case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
1122 	case USB_ID(0x046d, 0x08ca): /* Logitech Quickcam Fusion */
1123 	case USB_ID(0x046d, 0x0991):
1124 	case USB_ID(0x046d, 0x09a2): /* QuickCam Communicate Deluxe/S7500 */
1125 	/* Most audio usb devices lie about volume resolution.
1126 	 * Most Logitech webcams have res = 384.
1127 	 * Probably there is some logitech magic behind this number --fishor
1128 	 */
1129 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1130 			usb_audio_info(chip,
1131 				"set resolution quirk: cval->res = 384\n");
1132 			cval->res = 384;
1133 		}
1134 		break;
1135 	}
1136 }
1137 
1138 /*
1139  * retrieve the minimum and maximum values for the specified control
1140  */
1141 static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
1142 				   int default_min, struct snd_kcontrol *kctl)
1143 {
1144 	/* for failsafe */
1145 	cval->min = default_min;
1146 	cval->max = cval->min + 1;
1147 	cval->res = 1;
1148 	cval->dBmin = cval->dBmax = 0;
1149 
1150 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1151 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1152 		cval->initialized = 1;
1153 	} else {
1154 		int minchn = 0;
1155 		if (cval->cmask) {
1156 			int i;
1157 			for (i = 0; i < MAX_CHANNELS; i++)
1158 				if (cval->cmask & (1 << i)) {
1159 					minchn = i + 1;
1160 					break;
1161 				}
1162 		}
1163 		if (get_ctl_value(cval, UAC_GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
1164 		    get_ctl_value(cval, UAC_GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
1165 			usb_audio_err(cval->head.mixer->chip,
1166 				      "%d:%d: cannot get min/max values for control %d (id %d)\n",
1167 				   cval->head.id, snd_usb_ctrl_intf(cval->head.mixer->chip),
1168 							       cval->control, cval->head.id);
1169 			return -EINVAL;
1170 		}
1171 		if (get_ctl_value(cval, UAC_GET_RES,
1172 				  (cval->control << 8) | minchn,
1173 				  &cval->res) < 0) {
1174 			cval->res = 1;
1175 		} else {
1176 			int last_valid_res = cval->res;
1177 
1178 			while (cval->res > 1) {
1179 				if (snd_usb_mixer_set_ctl_value(cval, UAC_SET_RES,
1180 								(cval->control << 8) | minchn,
1181 								cval->res / 2) < 0)
1182 					break;
1183 				cval->res /= 2;
1184 			}
1185 			if (get_ctl_value(cval, UAC_GET_RES,
1186 					  (cval->control << 8) | minchn, &cval->res) < 0)
1187 				cval->res = last_valid_res;
1188 		}
1189 		if (cval->res == 0)
1190 			cval->res = 1;
1191 
1192 		/* Additional checks for the proper resolution
1193 		 *
1194 		 * Some devices report smaller resolutions than actually
1195 		 * reacting.  They don't return errors but simply clip
1196 		 * to the lower aligned value.
1197 		 */
1198 		if (cval->min + cval->res < cval->max) {
1199 			int last_valid_res = cval->res;
1200 			int saved, test, check;
1201 			get_cur_mix_raw(cval, minchn, &saved);
1202 			for (;;) {
1203 				test = saved;
1204 				if (test < cval->max)
1205 					test += cval->res;
1206 				else
1207 					test -= cval->res;
1208 				if (test < cval->min || test > cval->max ||
1209 				    snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||
1210 				    get_cur_mix_raw(cval, minchn, &check)) {
1211 					cval->res = last_valid_res;
1212 					break;
1213 				}
1214 				if (test == check)
1215 					break;
1216 				cval->res *= 2;
1217 			}
1218 			snd_usb_set_cur_mix_value(cval, minchn, 0, saved);
1219 		}
1220 
1221 		cval->initialized = 1;
1222 	}
1223 
1224 	if (kctl)
1225 		volume_control_quirks(cval, kctl);
1226 
1227 	/* USB descriptions contain the dB scale in 1/256 dB unit
1228 	 * while ALSA TLV contains in 1/100 dB unit
1229 	 */
1230 	cval->dBmin = (convert_signed_value(cval, cval->min) * 100) / 256;
1231 	cval->dBmax = (convert_signed_value(cval, cval->max) * 100) / 256;
1232 	if (cval->dBmin > cval->dBmax) {
1233 		/* something is wrong; assume it's either from/to 0dB */
1234 		if (cval->dBmin < 0)
1235 			cval->dBmax = 0;
1236 		else if (cval->dBmin > 0)
1237 			cval->dBmin = 0;
1238 		if (cval->dBmin > cval->dBmax) {
1239 			/* totally crap, return an error */
1240 			return -EINVAL;
1241 		}
1242 	}
1243 
1244 	return 0;
1245 }
1246 
1247 #define get_min_max(cval, def)	get_min_max_with_quirks(cval, def, NULL)
1248 
1249 /* get a feature/mixer unit info */
1250 static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol,
1251 				  struct snd_ctl_elem_info *uinfo)
1252 {
1253 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1254 
1255 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1256 	    cval->val_type == USB_MIXER_INV_BOOLEAN)
1257 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1258 	else
1259 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1260 	uinfo->count = cval->channels;
1261 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1262 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1263 		uinfo->value.integer.min = 0;
1264 		uinfo->value.integer.max = 1;
1265 	} else {
1266 		if (!cval->initialized) {
1267 			get_min_max_with_quirks(cval, 0, kcontrol);
1268 			if (cval->initialized && cval->dBmin >= cval->dBmax) {
1269 				kcontrol->vd[0].access &=
1270 					~(SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1271 					  SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
1272 				snd_ctl_notify(cval->head.mixer->chip->card,
1273 					       SNDRV_CTL_EVENT_MASK_INFO,
1274 					       &kcontrol->id);
1275 			}
1276 		}
1277 		uinfo->value.integer.min = 0;
1278 		uinfo->value.integer.max =
1279 			(cval->max - cval->min + cval->res - 1) / cval->res;
1280 	}
1281 	return 0;
1282 }
1283 
1284 /* get the current value from feature/mixer unit */
1285 static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol,
1286 				 struct snd_ctl_elem_value *ucontrol)
1287 {
1288 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1289 	int c, cnt, val, err;
1290 
1291 	ucontrol->value.integer.value[0] = cval->min;
1292 	if (cval->cmask) {
1293 		cnt = 0;
1294 		for (c = 0; c < MAX_CHANNELS; c++) {
1295 			if (!(cval->cmask & (1 << c)))
1296 				continue;
1297 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &val);
1298 			if (err < 0)
1299 				return filter_error(cval, err);
1300 			val = get_relative_value(cval, val);
1301 			ucontrol->value.integer.value[cnt] = val;
1302 			cnt++;
1303 		}
1304 		return 0;
1305 	} else {
1306 		/* master channel */
1307 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1308 		if (err < 0)
1309 			return filter_error(cval, err);
1310 		val = get_relative_value(cval, val);
1311 		ucontrol->value.integer.value[0] = val;
1312 	}
1313 	return 0;
1314 }
1315 
1316 /* put the current value to feature/mixer unit */
1317 static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol,
1318 				 struct snd_ctl_elem_value *ucontrol)
1319 {
1320 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1321 	int c, cnt, val, oval, err;
1322 	int changed = 0;
1323 
1324 	if (cval->cmask) {
1325 		cnt = 0;
1326 		for (c = 0; c < MAX_CHANNELS; c++) {
1327 			if (!(cval->cmask & (1 << c)))
1328 				continue;
1329 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &oval);
1330 			if (err < 0)
1331 				return filter_error(cval, err);
1332 			val = ucontrol->value.integer.value[cnt];
1333 			val = get_abs_value(cval, val);
1334 			if (oval != val) {
1335 				snd_usb_set_cur_mix_value(cval, c + 1, cnt, val);
1336 				changed = 1;
1337 			}
1338 			cnt++;
1339 		}
1340 	} else {
1341 		/* master channel */
1342 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &oval);
1343 		if (err < 0)
1344 			return filter_error(cval, err);
1345 		val = ucontrol->value.integer.value[0];
1346 		val = get_abs_value(cval, val);
1347 		if (val != oval) {
1348 			snd_usb_set_cur_mix_value(cval, 0, 0, val);
1349 			changed = 1;
1350 		}
1351 	}
1352 	return changed;
1353 }
1354 
1355 /* get the boolean value from the master channel of a UAC control */
1356 static int mixer_ctl_master_bool_get(struct snd_kcontrol *kcontrol,
1357 				     struct snd_ctl_elem_value *ucontrol)
1358 {
1359 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1360 	int val, err;
1361 
1362 	err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1363 	if (err < 0)
1364 		return filter_error(cval, err);
1365 	val = (val != 0);
1366 	ucontrol->value.integer.value[0] = val;
1367 	return 0;
1368 }
1369 
1370 /* get the connectors status and report it as boolean type */
1371 static int mixer_ctl_connector_get(struct snd_kcontrol *kcontrol,
1372 				   struct snd_ctl_elem_value *ucontrol)
1373 {
1374 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1375 	struct snd_usb_audio *chip = cval->head.mixer->chip;
1376 	int idx = 0, validx, ret, val;
1377 
1378 	validx = cval->control << 8 | 0;
1379 
1380 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
1381 	if (ret)
1382 		goto error;
1383 
1384 	idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
1385 	if (cval->head.mixer->protocol == UAC_VERSION_2) {
1386 		struct uac2_connectors_ctl_blk uac2_conn;
1387 
1388 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1389 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1390 				      validx, idx, &uac2_conn, sizeof(uac2_conn));
1391 		val = !!uac2_conn.bNrChannels;
1392 	} else { /* UAC_VERSION_3 */
1393 		struct uac3_insertion_ctl_blk uac3_conn;
1394 
1395 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1396 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1397 				      validx, idx, &uac3_conn, sizeof(uac3_conn));
1398 		val = !!uac3_conn.bmConInserted;
1399 	}
1400 
1401 	snd_usb_unlock_shutdown(chip);
1402 
1403 	if (ret < 0) {
1404 error:
1405 		usb_audio_err(chip,
1406 			"cannot get connectors status: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
1407 			UAC_GET_CUR, validx, idx, cval->val_type);
1408 		return ret;
1409 	}
1410 
1411 	ucontrol->value.integer.value[0] = val;
1412 	return 0;
1413 }
1414 
1415 static struct snd_kcontrol_new usb_feature_unit_ctl = {
1416 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1417 	.name = "", /* will be filled later manually */
1418 	.info = mixer_ctl_feature_info,
1419 	.get = mixer_ctl_feature_get,
1420 	.put = mixer_ctl_feature_put,
1421 };
1422 
1423 /* the read-only variant */
1424 static const struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
1425 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1426 	.name = "", /* will be filled later manually */
1427 	.info = mixer_ctl_feature_info,
1428 	.get = mixer_ctl_feature_get,
1429 	.put = NULL,
1430 };
1431 
1432 /*
1433  * A control which shows the boolean value from reading a UAC control on
1434  * the master channel.
1435  */
1436 static struct snd_kcontrol_new usb_bool_master_control_ctl_ro = {
1437 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1438 	.name = "", /* will be filled later manually */
1439 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1440 	.info = snd_ctl_boolean_mono_info,
1441 	.get = mixer_ctl_master_bool_get,
1442 	.put = NULL,
1443 };
1444 
1445 static const struct snd_kcontrol_new usb_connector_ctl_ro = {
1446 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1447 	.name = "", /* will be filled later manually */
1448 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1449 	.info = snd_ctl_boolean_mono_info,
1450 	.get = mixer_ctl_connector_get,
1451 	.put = NULL,
1452 };
1453 
1454 /*
1455  * This symbol is exported in order to allow the mixer quirks to
1456  * hook up to the standard feature unit control mechanism
1457  */
1458 struct snd_kcontrol_new *snd_usb_feature_unit_ctl = &usb_feature_unit_ctl;
1459 
1460 /*
1461  * build a feature control
1462  */
1463 static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
1464 {
1465 	return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
1466 }
1467 
1468 /*
1469  * A lot of headsets/headphones have a "Speaker" mixer. Make sure we
1470  * rename it to "Headphone". We determine if something is a headphone
1471  * similar to how udev determines form factor.
1472  */
1473 static void check_no_speaker_on_headset(struct snd_kcontrol *kctl,
1474 					struct snd_card *card)
1475 {
1476 	const char *names_to_check[] = {
1477 		"Headset", "headset", "Headphone", "headphone", NULL};
1478 	const char **s;
1479 	bool found = false;
1480 
1481 	if (strcmp("Speaker", kctl->id.name))
1482 		return;
1483 
1484 	for (s = names_to_check; *s; s++)
1485 		if (strstr(card->shortname, *s)) {
1486 			found = true;
1487 			break;
1488 		}
1489 
1490 	if (!found)
1491 		return;
1492 
1493 	strlcpy(kctl->id.name, "Headphone", sizeof(kctl->id.name));
1494 }
1495 
1496 static struct usb_feature_control_info *get_feature_control_info(int control)
1497 {
1498 	int i;
1499 
1500 	for (i = 0; i < ARRAY_SIZE(audio_feature_info); ++i) {
1501 		if (audio_feature_info[i].control == control)
1502 			return &audio_feature_info[i];
1503 	}
1504 	return NULL;
1505 }
1506 
1507 static void __build_feature_ctl(struct usb_mixer_interface *mixer,
1508 				const struct usbmix_name_map *imap,
1509 				unsigned int ctl_mask, int control,
1510 				struct usb_audio_term *iterm,
1511 				struct usb_audio_term *oterm,
1512 				int unitid, int nameid, int readonly_mask)
1513 {
1514 	struct usb_feature_control_info *ctl_info;
1515 	unsigned int len = 0;
1516 	int mapped_name = 0;
1517 	struct snd_kcontrol *kctl;
1518 	struct usb_mixer_elem_info *cval;
1519 	const struct usbmix_name_map *map;
1520 	unsigned int range;
1521 
1522 	if (control == UAC_FU_GRAPHIC_EQUALIZER) {
1523 		/* FIXME: not supported yet */
1524 		return;
1525 	}
1526 
1527 	map = find_map(imap, unitid, control);
1528 	if (check_ignored_ctl(map))
1529 		return;
1530 
1531 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1532 	if (!cval)
1533 		return;
1534 	snd_usb_mixer_elem_init_std(&cval->head, mixer, unitid);
1535 	cval->control = control;
1536 	cval->cmask = ctl_mask;
1537 
1538 	ctl_info = get_feature_control_info(control);
1539 	if (!ctl_info) {
1540 		kfree(cval);
1541 		return;
1542 	}
1543 	if (mixer->protocol == UAC_VERSION_1)
1544 		cval->val_type = ctl_info->type;
1545 	else /* UAC_VERSION_2 */
1546 		cval->val_type = ctl_info->type_uac2 >= 0 ?
1547 			ctl_info->type_uac2 : ctl_info->type;
1548 
1549 	if (ctl_mask == 0) {
1550 		cval->channels = 1;	/* master channel */
1551 		cval->master_readonly = readonly_mask;
1552 	} else {
1553 		int i, c = 0;
1554 		for (i = 0; i < 16; i++)
1555 			if (ctl_mask & (1 << i))
1556 				c++;
1557 		cval->channels = c;
1558 		cval->ch_readonly = readonly_mask;
1559 	}
1560 
1561 	/*
1562 	 * If all channels in the mask are marked read-only, make the control
1563 	 * read-only. snd_usb_set_cur_mix_value() will check the mask again and won't
1564 	 * issue write commands to read-only channels.
1565 	 */
1566 	if (cval->channels == readonly_mask)
1567 		kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
1568 	else
1569 		kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1570 
1571 	if (!kctl) {
1572 		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
1573 		kfree(cval);
1574 		return;
1575 	}
1576 	kctl->private_free = snd_usb_mixer_elem_free;
1577 
1578 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1579 	mapped_name = len != 0;
1580 	if (!len && nameid)
1581 		len = snd_usb_copy_string_desc(mixer->chip, nameid,
1582 				kctl->id.name, sizeof(kctl->id.name));
1583 
1584 	switch (control) {
1585 	case UAC_FU_MUTE:
1586 	case UAC_FU_VOLUME:
1587 		/*
1588 		 * determine the control name.  the rule is:
1589 		 * - if a name id is given in descriptor, use it.
1590 		 * - if the connected input can be determined, then use the name
1591 		 *   of terminal type.
1592 		 * - if the connected output can be determined, use it.
1593 		 * - otherwise, anonymous name.
1594 		 */
1595 		if (!len) {
1596 			if (iterm)
1597 				len = get_term_name(mixer->chip, iterm,
1598 						    kctl->id.name,
1599 						    sizeof(kctl->id.name), 1);
1600 			if (!len && oterm)
1601 				len = get_term_name(mixer->chip, oterm,
1602 						    kctl->id.name,
1603 						    sizeof(kctl->id.name), 1);
1604 			if (!len)
1605 				snprintf(kctl->id.name, sizeof(kctl->id.name),
1606 					 "Feature %d", unitid);
1607 		}
1608 
1609 		if (!mapped_name)
1610 			check_no_speaker_on_headset(kctl, mixer->chip->card);
1611 
1612 		/*
1613 		 * determine the stream direction:
1614 		 * if the connected output is USB stream, then it's likely a
1615 		 * capture stream.  otherwise it should be playback (hopefully :)
1616 		 */
1617 		if (!mapped_name && oterm && !(oterm->type >> 16)) {
1618 			if ((oterm->type & 0xff00) == 0x0100)
1619 				append_ctl_name(kctl, " Capture");
1620 			else
1621 				append_ctl_name(kctl, " Playback");
1622 		}
1623 		append_ctl_name(kctl, control == UAC_FU_MUTE ?
1624 				" Switch" : " Volume");
1625 		break;
1626 	default:
1627 		if (!len)
1628 			strlcpy(kctl->id.name, audio_feature_info[control-1].name,
1629 				sizeof(kctl->id.name));
1630 		break;
1631 	}
1632 
1633 	/* get min/max values */
1634 	get_min_max_with_quirks(cval, 0, kctl);
1635 
1636 	if (control == UAC_FU_VOLUME) {
1637 		check_mapped_dB(map, cval);
1638 		if (cval->dBmin < cval->dBmax || !cval->initialized) {
1639 			kctl->tlv.c = snd_usb_mixer_vol_tlv;
1640 			kctl->vd[0].access |=
1641 				SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1642 				SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1643 		}
1644 	}
1645 
1646 	snd_usb_mixer_fu_apply_quirk(mixer, cval, unitid, kctl);
1647 
1648 	range = (cval->max - cval->min) / cval->res;
1649 	/*
1650 	 * Are there devices with volume range more than 255? I use a bit more
1651 	 * to be sure. 384 is a resolution magic number found on Logitech
1652 	 * devices. It will definitively catch all buggy Logitech devices.
1653 	 */
1654 	if (range > 384) {
1655 		usb_audio_warn(mixer->chip,
1656 			       "Warning! Unlikely big volume range (=%u), cval->res is probably wrong.",
1657 			       range);
1658 		usb_audio_warn(mixer->chip,
1659 			       "[%d] FU [%s] ch = %d, val = %d/%d/%d",
1660 			       cval->head.id, kctl->id.name, cval->channels,
1661 			       cval->min, cval->max, cval->res);
1662 	}
1663 
1664 	usb_audio_dbg(mixer->chip, "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
1665 		      cval->head.id, kctl->id.name, cval->channels,
1666 		      cval->min, cval->max, cval->res);
1667 	snd_usb_mixer_add_control(&cval->head, kctl);
1668 }
1669 
1670 static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
1671 			      unsigned int ctl_mask, int control,
1672 			      struct usb_audio_term *iterm, int unitid,
1673 			      int readonly_mask)
1674 {
1675 	struct uac_feature_unit_descriptor *desc = raw_desc;
1676 	int nameid = uac_feature_unit_iFeature(desc);
1677 
1678 	__build_feature_ctl(state->mixer, state->map, ctl_mask, control,
1679 			iterm, &state->oterm, unitid, nameid, readonly_mask);
1680 }
1681 
1682 static void build_feature_ctl_badd(struct usb_mixer_interface *mixer,
1683 			      unsigned int ctl_mask, int control, int unitid,
1684 			      const struct usbmix_name_map *badd_map)
1685 {
1686 	__build_feature_ctl(mixer, badd_map, ctl_mask, control,
1687 			NULL, NULL, unitid, 0, 0);
1688 }
1689 
1690 static void get_connector_control_name(struct usb_mixer_interface *mixer,
1691 				       struct usb_audio_term *term,
1692 				       bool is_input, char *name, int name_size)
1693 {
1694 	int name_len = get_term_name(mixer->chip, term, name, name_size, 0);
1695 
1696 	if (name_len == 0)
1697 		strlcpy(name, "Unknown", name_size);
1698 
1699 	/*
1700 	 *  sound/core/ctljack.c has a convention of naming jack controls
1701 	 * by ending in " Jack".  Make it slightly more useful by
1702 	 * indicating Input or Output after the terminal name.
1703 	 */
1704 	if (is_input)
1705 		strlcat(name, " - Input Jack", name_size);
1706 	else
1707 		strlcat(name, " - Output Jack", name_size);
1708 }
1709 
1710 /* Build a mixer control for a UAC connector control (jack-detect) */
1711 static void build_connector_control(struct usb_mixer_interface *mixer,
1712 				    struct usb_audio_term *term, bool is_input)
1713 {
1714 	struct snd_kcontrol *kctl;
1715 	struct usb_mixer_elem_info *cval;
1716 
1717 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1718 	if (!cval)
1719 		return;
1720 	snd_usb_mixer_elem_init_std(&cval->head, mixer, term->id);
1721 	/*
1722 	 * UAC2: The first byte from reading the UAC2_TE_CONNECTOR control returns the
1723 	 * number of channels connected.
1724 	 *
1725 	 * UAC3: The first byte specifies size of bitmap for the inserted controls. The
1726 	 * following byte(s) specifies which connectors are inserted.
1727 	 *
1728 	 * This boolean ctl will simply report if any channels are connected
1729 	 * or not.
1730 	 */
1731 	if (mixer->protocol == UAC_VERSION_2)
1732 		cval->control = UAC2_TE_CONNECTOR;
1733 	else /* UAC_VERSION_3 */
1734 		cval->control = UAC3_TE_INSERTION;
1735 
1736 	cval->val_type = USB_MIXER_BOOLEAN;
1737 	cval->channels = 1; /* report true if any channel is connected */
1738 	cval->min = 0;
1739 	cval->max = 1;
1740 	kctl = snd_ctl_new1(&usb_connector_ctl_ro, cval);
1741 	if (!kctl) {
1742 		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
1743 		kfree(cval);
1744 		return;
1745 	}
1746 	get_connector_control_name(mixer, term, is_input, kctl->id.name,
1747 				   sizeof(kctl->id.name));
1748 	kctl->private_free = snd_usb_mixer_elem_free;
1749 	snd_usb_mixer_add_control(&cval->head, kctl);
1750 }
1751 
1752 static int parse_clock_source_unit(struct mixer_build *state, int unitid,
1753 				   void *_ftr)
1754 {
1755 	struct uac_clock_source_descriptor *hdr = _ftr;
1756 	struct usb_mixer_elem_info *cval;
1757 	struct snd_kcontrol *kctl;
1758 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
1759 	int ret;
1760 
1761 	if (state->mixer->protocol != UAC_VERSION_2)
1762 		return -EINVAL;
1763 
1764 	if (hdr->bLength != sizeof(*hdr)) {
1765 		usb_audio_dbg(state->chip,
1766 			      "Bogus clock source descriptor length of %d, ignoring.\n",
1767 			      hdr->bLength);
1768 		return 0;
1769 	}
1770 
1771 	/*
1772 	 * The only property of this unit we are interested in is the
1773 	 * clock source validity. If that isn't readable, just bail out.
1774 	 */
1775 	if (!uac_v2v3_control_is_readable(hdr->bmControls,
1776 				      UAC2_CS_CONTROL_CLOCK_VALID))
1777 		return 0;
1778 
1779 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1780 	if (!cval)
1781 		return -ENOMEM;
1782 
1783 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, hdr->bClockID);
1784 
1785 	cval->min = 0;
1786 	cval->max = 1;
1787 	cval->channels = 1;
1788 	cval->val_type = USB_MIXER_BOOLEAN;
1789 	cval->control = UAC2_CS_CONTROL_CLOCK_VALID;
1790 
1791 	cval->master_readonly = 1;
1792 	/* From UAC2 5.2.5.1.2 "Only the get request is supported." */
1793 	kctl = snd_ctl_new1(&usb_bool_master_control_ctl_ro, cval);
1794 
1795 	if (!kctl) {
1796 		kfree(cval);
1797 		return -ENOMEM;
1798 	}
1799 
1800 	kctl->private_free = snd_usb_mixer_elem_free;
1801 	ret = snd_usb_copy_string_desc(state->chip, hdr->iClockSource,
1802 				       name, sizeof(name));
1803 	if (ret > 0)
1804 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1805 			 "%s Validity", name);
1806 	else
1807 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1808 			 "Clock Source %d Validity", hdr->bClockID);
1809 
1810 	return snd_usb_mixer_add_control(&cval->head, kctl);
1811 }
1812 
1813 /*
1814  * parse a feature unit
1815  *
1816  * most of controls are defined here.
1817  */
1818 static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
1819 				    void *_ftr)
1820 {
1821 	int channels, i, j;
1822 	struct usb_audio_term iterm;
1823 	unsigned int master_bits;
1824 	int err, csize;
1825 	struct uac_feature_unit_descriptor *hdr = _ftr;
1826 	__u8 *bmaControls;
1827 
1828 	if (state->mixer->protocol == UAC_VERSION_1) {
1829 		if (hdr->bLength < 7) {
1830 			usb_audio_err(state->chip,
1831 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1832 				      unitid);
1833 			return -EINVAL;
1834 		}
1835 		csize = hdr->bControlSize;
1836 		if (!csize) {
1837 			usb_audio_dbg(state->chip,
1838 				      "unit %u: invalid bControlSize == 0\n",
1839 				      unitid);
1840 			return -EINVAL;
1841 		}
1842 		channels = (hdr->bLength - 7) / csize - 1;
1843 		bmaControls = hdr->bmaControls;
1844 		if (hdr->bLength < 7 + csize) {
1845 			usb_audio_err(state->chip,
1846 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1847 				      unitid);
1848 			return -EINVAL;
1849 		}
1850 	} else if (state->mixer->protocol == UAC_VERSION_2) {
1851 		struct uac2_feature_unit_descriptor *ftr = _ftr;
1852 		if (hdr->bLength < 6) {
1853 			usb_audio_err(state->chip,
1854 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1855 				      unitid);
1856 			return -EINVAL;
1857 		}
1858 		csize = 4;
1859 		channels = (hdr->bLength - 6) / 4 - 1;
1860 		bmaControls = ftr->bmaControls;
1861 		if (hdr->bLength < 6 + csize) {
1862 			usb_audio_err(state->chip,
1863 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1864 				      unitid);
1865 			return -EINVAL;
1866 		}
1867 	} else { /* UAC_VERSION_3 */
1868 		struct uac3_feature_unit_descriptor *ftr = _ftr;
1869 
1870 		if (hdr->bLength < 7) {
1871 			usb_audio_err(state->chip,
1872 				      "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n",
1873 				      unitid);
1874 			return -EINVAL;
1875 		}
1876 		csize = 4;
1877 		channels = (ftr->bLength - 7) / 4 - 1;
1878 		bmaControls = ftr->bmaControls;
1879 		if (hdr->bLength < 7 + csize) {
1880 			usb_audio_err(state->chip,
1881 				      "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n",
1882 				      unitid);
1883 			return -EINVAL;
1884 		}
1885 	}
1886 
1887 	/* parse the source unit */
1888 	err = parse_audio_unit(state, hdr->bSourceID);
1889 	if (err < 0)
1890 		return err;
1891 
1892 	/* determine the input source type and name */
1893 	err = check_input_term(state, hdr->bSourceID, &iterm);
1894 	if (err < 0)
1895 		return err;
1896 
1897 	master_bits = snd_usb_combine_bytes(bmaControls, csize);
1898 	/* master configuration quirks */
1899 	switch (state->chip->usb_id) {
1900 	case USB_ID(0x08bb, 0x2702):
1901 		usb_audio_info(state->chip,
1902 			       "usbmixer: master volume quirk for PCM2702 chip\n");
1903 		/* disable non-functional volume control */
1904 		master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
1905 		break;
1906 	case USB_ID(0x1130, 0xf211):
1907 		usb_audio_info(state->chip,
1908 			       "usbmixer: volume control quirk for Tenx TP6911 Audio Headset\n");
1909 		/* disable non-functional volume control */
1910 		channels = 0;
1911 		break;
1912 
1913 	}
1914 
1915 	if (state->mixer->protocol == UAC_VERSION_1) {
1916 		/* check all control types */
1917 		for (i = 0; i < 10; i++) {
1918 			unsigned int ch_bits = 0;
1919 			int control = audio_feature_info[i].control;
1920 
1921 			for (j = 0; j < channels; j++) {
1922 				unsigned int mask;
1923 
1924 				mask = snd_usb_combine_bytes(bmaControls +
1925 							     csize * (j+1), csize);
1926 				if (mask & (1 << i))
1927 					ch_bits |= (1 << j);
1928 			}
1929 			/* audio class v1 controls are never read-only */
1930 
1931 			/*
1932 			 * The first channel must be set
1933 			 * (for ease of programming).
1934 			 */
1935 			if (ch_bits & 1)
1936 				build_feature_ctl(state, _ftr, ch_bits, control,
1937 						  &iterm, unitid, 0);
1938 			if (master_bits & (1 << i))
1939 				build_feature_ctl(state, _ftr, 0, control,
1940 						  &iterm, unitid, 0);
1941 		}
1942 	} else { /* UAC_VERSION_2/3 */
1943 		for (i = 0; i < ARRAY_SIZE(audio_feature_info); i++) {
1944 			unsigned int ch_bits = 0;
1945 			unsigned int ch_read_only = 0;
1946 			int control = audio_feature_info[i].control;
1947 
1948 			for (j = 0; j < channels; j++) {
1949 				unsigned int mask;
1950 
1951 				mask = snd_usb_combine_bytes(bmaControls +
1952 							     csize * (j+1), csize);
1953 				if (uac_v2v3_control_is_readable(mask, control)) {
1954 					ch_bits |= (1 << j);
1955 					if (!uac_v2v3_control_is_writeable(mask, control))
1956 						ch_read_only |= (1 << j);
1957 				}
1958 			}
1959 
1960 			/*
1961 			 * NOTE: build_feature_ctl() will mark the control
1962 			 * read-only if all channels are marked read-only in
1963 			 * the descriptors. Otherwise, the control will be
1964 			 * reported as writeable, but the driver will not
1965 			 * actually issue a write command for read-only
1966 			 * channels.
1967 			 */
1968 
1969 			/*
1970 			 * The first channel must be set
1971 			 * (for ease of programming).
1972 			 */
1973 			if (ch_bits & 1)
1974 				build_feature_ctl(state, _ftr, ch_bits, control,
1975 						  &iterm, unitid, ch_read_only);
1976 			if (uac_v2v3_control_is_readable(master_bits, control))
1977 				build_feature_ctl(state, _ftr, 0, control,
1978 						  &iterm, unitid,
1979 						  !uac_v2v3_control_is_writeable(master_bits,
1980 										 control));
1981 		}
1982 	}
1983 
1984 	return 0;
1985 }
1986 
1987 /*
1988  * Mixer Unit
1989  */
1990 
1991 /*
1992  * build a mixer unit control
1993  *
1994  * the callbacks are identical with feature unit.
1995  * input channel number (zero based) is given in control field instead.
1996  */
1997 static void build_mixer_unit_ctl(struct mixer_build *state,
1998 				 struct uac_mixer_unit_descriptor *desc,
1999 				 int in_pin, int in_ch, int num_outs,
2000 				 int unitid, struct usb_audio_term *iterm)
2001 {
2002 	struct usb_mixer_elem_info *cval;
2003 	unsigned int i, len;
2004 	struct snd_kcontrol *kctl;
2005 	const struct usbmix_name_map *map;
2006 
2007 	map = find_map(state->map, unitid, 0);
2008 	if (check_ignored_ctl(map))
2009 		return;
2010 
2011 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2012 	if (!cval)
2013 		return;
2014 
2015 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2016 	cval->control = in_ch + 1; /* based on 1 */
2017 	cval->val_type = USB_MIXER_S16;
2018 	for (i = 0; i < num_outs; i++) {
2019 		__u8 *c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
2020 
2021 		if (check_matrix_bitmap(c, in_ch, i, num_outs)) {
2022 			cval->cmask |= (1 << i);
2023 			cval->channels++;
2024 		}
2025 	}
2026 
2027 	/* get min/max values */
2028 	get_min_max(cval, 0);
2029 
2030 	kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
2031 	if (!kctl) {
2032 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2033 		kfree(cval);
2034 		return;
2035 	}
2036 	kctl->private_free = snd_usb_mixer_elem_free;
2037 
2038 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2039 	if (!len)
2040 		len = get_term_name(state->chip, iterm, kctl->id.name,
2041 				    sizeof(kctl->id.name), 0);
2042 	if (!len)
2043 		len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
2044 	append_ctl_name(kctl, " Volume");
2045 
2046 	usb_audio_dbg(state->chip, "[%d] MU [%s] ch = %d, val = %d/%d\n",
2047 		    cval->head.id, kctl->id.name, cval->channels, cval->min, cval->max);
2048 	snd_usb_mixer_add_control(&cval->head, kctl);
2049 }
2050 
2051 static int parse_audio_input_terminal(struct mixer_build *state, int unitid,
2052 				      void *raw_desc)
2053 {
2054 	struct usb_audio_term iterm;
2055 	unsigned int control, bmctls, term_id;
2056 
2057 	if (state->mixer->protocol == UAC_VERSION_2) {
2058 		struct uac2_input_terminal_descriptor *d_v2 = raw_desc;
2059 		if (d_v2->bLength < sizeof(*d_v2))
2060 			return -EINVAL;
2061 		control = UAC2_TE_CONNECTOR;
2062 		term_id = d_v2->bTerminalID;
2063 		bmctls = le16_to_cpu(d_v2->bmControls);
2064 	} else if (state->mixer->protocol == UAC_VERSION_3) {
2065 		struct uac3_input_terminal_descriptor *d_v3 = raw_desc;
2066 		if (d_v3->bLength < sizeof(*d_v3))
2067 			return -EINVAL;
2068 		control = UAC3_TE_INSERTION;
2069 		term_id = d_v3->bTerminalID;
2070 		bmctls = le32_to_cpu(d_v3->bmControls);
2071 	} else {
2072 		return 0; /* UAC1. No Insertion control */
2073 	}
2074 
2075 	check_input_term(state, term_id, &iterm);
2076 
2077 	/* Check for jack detection. */
2078 	if (uac_v2v3_control_is_readable(bmctls, control))
2079 		build_connector_control(state->mixer, &iterm, true);
2080 
2081 	return 0;
2082 }
2083 
2084 /*
2085  * parse a mixer unit
2086  */
2087 static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
2088 				  void *raw_desc)
2089 {
2090 	struct uac_mixer_unit_descriptor *desc = raw_desc;
2091 	struct usb_audio_term iterm;
2092 	int input_pins, num_ins, num_outs;
2093 	int pin, ich, err;
2094 
2095 	err = uac_mixer_unit_get_channels(state, desc);
2096 	if (err < 0) {
2097 		usb_audio_err(state->chip,
2098 			      "invalid MIXER UNIT descriptor %d\n",
2099 			      unitid);
2100 		return err;
2101 	}
2102 
2103 	num_outs = err;
2104 	input_pins = desc->bNrInPins;
2105 
2106 	num_ins = 0;
2107 	ich = 0;
2108 	for (pin = 0; pin < input_pins; pin++) {
2109 		err = parse_audio_unit(state, desc->baSourceID[pin]);
2110 		if (err < 0)
2111 			continue;
2112 		/* no bmControls field (e.g. Maya44) -> ignore */
2113 		if (!num_outs)
2114 			continue;
2115 		err = check_input_term(state, desc->baSourceID[pin], &iterm);
2116 		if (err < 0)
2117 			return err;
2118 		num_ins += iterm.channels;
2119 		for (; ich < num_ins; ich++) {
2120 			int och, ich_has_controls = 0;
2121 
2122 			for (och = 0; och < num_outs; och++) {
2123 				__u8 *c = uac_mixer_unit_bmControls(desc,
2124 						state->mixer->protocol);
2125 
2126 				if (check_matrix_bitmap(c, ich, och, num_outs)) {
2127 					ich_has_controls = 1;
2128 					break;
2129 				}
2130 			}
2131 			if (ich_has_controls)
2132 				build_mixer_unit_ctl(state, desc, pin, ich, num_outs,
2133 						     unitid, &iterm);
2134 		}
2135 	}
2136 	return 0;
2137 }
2138 
2139 /*
2140  * Processing Unit / Extension Unit
2141  */
2142 
2143 /* get callback for processing/extension unit */
2144 static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol,
2145 				  struct snd_ctl_elem_value *ucontrol)
2146 {
2147 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2148 	int err, val;
2149 
2150 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2151 	if (err < 0) {
2152 		ucontrol->value.integer.value[0] = cval->min;
2153 		return filter_error(cval, err);
2154 	}
2155 	val = get_relative_value(cval, val);
2156 	ucontrol->value.integer.value[0] = val;
2157 	return 0;
2158 }
2159 
2160 /* put callback for processing/extension unit */
2161 static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol,
2162 				  struct snd_ctl_elem_value *ucontrol)
2163 {
2164 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2165 	int val, oval, err;
2166 
2167 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2168 	if (err < 0)
2169 		return filter_error(cval, err);
2170 	val = ucontrol->value.integer.value[0];
2171 	val = get_abs_value(cval, val);
2172 	if (val != oval) {
2173 		set_cur_ctl_value(cval, cval->control << 8, val);
2174 		return 1;
2175 	}
2176 	return 0;
2177 }
2178 
2179 /* alsa control interface for processing/extension unit */
2180 static const struct snd_kcontrol_new mixer_procunit_ctl = {
2181 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2182 	.name = "", /* will be filled later */
2183 	.info = mixer_ctl_feature_info,
2184 	.get = mixer_ctl_procunit_get,
2185 	.put = mixer_ctl_procunit_put,
2186 };
2187 
2188 /*
2189  * predefined data for processing units
2190  */
2191 struct procunit_value_info {
2192 	int control;
2193 	char *suffix;
2194 	int val_type;
2195 	int min_value;
2196 };
2197 
2198 struct procunit_info {
2199 	int type;
2200 	char *name;
2201 	struct procunit_value_info *values;
2202 };
2203 
2204 static struct procunit_value_info undefined_proc_info[] = {
2205 	{ 0x00, "Control Undefined", 0 },
2206 	{ 0 }
2207 };
2208 
2209 static struct procunit_value_info updown_proc_info[] = {
2210 	{ UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2211 	{ UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2212 	{ 0 }
2213 };
2214 static struct procunit_value_info prologic_proc_info[] = {
2215 	{ UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2216 	{ UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2217 	{ 0 }
2218 };
2219 static struct procunit_value_info threed_enh_proc_info[] = {
2220 	{ UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2221 	{ UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
2222 	{ 0 }
2223 };
2224 static struct procunit_value_info reverb_proc_info[] = {
2225 	{ UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2226 	{ UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
2227 	{ UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
2228 	{ UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
2229 	{ 0 }
2230 };
2231 static struct procunit_value_info chorus_proc_info[] = {
2232 	{ UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2233 	{ UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
2234 	{ UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
2235 	{ UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
2236 	{ 0 }
2237 };
2238 static struct procunit_value_info dcr_proc_info[] = {
2239 	{ UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2240 	{ UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
2241 	{ UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
2242 	{ UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
2243 	{ UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
2244 	{ UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
2245 	{ 0 }
2246 };
2247 
2248 static struct procunit_info procunits[] = {
2249 	{ UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
2250 	{ UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
2251 	{ UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
2252 	{ UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
2253 	{ UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
2254 	{ UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
2255 	{ 0 },
2256 };
2257 
2258 static struct procunit_value_info uac3_updown_proc_info[] = {
2259 	{ UAC3_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2260 	{ 0 }
2261 };
2262 static struct procunit_value_info uac3_stereo_ext_proc_info[] = {
2263 	{ UAC3_EXT_WIDTH_CONTROL, "Width Control", USB_MIXER_U8 },
2264 	{ 0 }
2265 };
2266 
2267 static struct procunit_info uac3_procunits[] = {
2268 	{ UAC3_PROCESS_UP_DOWNMIX, "Up Down", uac3_updown_proc_info },
2269 	{ UAC3_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", uac3_stereo_ext_proc_info },
2270 	{ UAC3_PROCESS_MULTI_FUNCTION, "Multi-Function", undefined_proc_info },
2271 	{ 0 },
2272 };
2273 
2274 /*
2275  * predefined data for extension units
2276  */
2277 static struct procunit_value_info clock_rate_xu_info[] = {
2278 	{ USB_XU_CLOCK_RATE_SELECTOR, "Selector", USB_MIXER_U8, 0 },
2279 	{ 0 }
2280 };
2281 static struct procunit_value_info clock_source_xu_info[] = {
2282 	{ USB_XU_CLOCK_SOURCE_SELECTOR, "External", USB_MIXER_BOOLEAN },
2283 	{ 0 }
2284 };
2285 static struct procunit_value_info spdif_format_xu_info[] = {
2286 	{ USB_XU_DIGITAL_FORMAT_SELECTOR, "SPDIF/AC3", USB_MIXER_BOOLEAN },
2287 	{ 0 }
2288 };
2289 static struct procunit_value_info soft_limit_xu_info[] = {
2290 	{ USB_XU_SOFT_LIMIT_SELECTOR, " ", USB_MIXER_BOOLEAN },
2291 	{ 0 }
2292 };
2293 static struct procunit_info extunits[] = {
2294 	{ USB_XU_CLOCK_RATE, "Clock rate", clock_rate_xu_info },
2295 	{ USB_XU_CLOCK_SOURCE, "DigitalIn CLK source", clock_source_xu_info },
2296 	{ USB_XU_DIGITAL_IO_STATUS, "DigitalOut format:", spdif_format_xu_info },
2297 	{ USB_XU_DEVICE_OPTIONS, "AnalogueIn Soft Limit", soft_limit_xu_info },
2298 	{ 0 }
2299 };
2300 
2301 /*
2302  * build a processing/extension unit
2303  */
2304 static int build_audio_procunit(struct mixer_build *state, int unitid,
2305 				void *raw_desc, struct procunit_info *list,
2306 				bool extension_unit)
2307 {
2308 	struct uac_processing_unit_descriptor *desc = raw_desc;
2309 	int num_ins;
2310 	struct usb_mixer_elem_info *cval;
2311 	struct snd_kcontrol *kctl;
2312 	int i, err, nameid, type, len;
2313 	struct procunit_info *info;
2314 	struct procunit_value_info *valinfo;
2315 	const struct usbmix_name_map *map;
2316 	static struct procunit_value_info default_value_info[] = {
2317 		{ 0x01, "Switch", USB_MIXER_BOOLEAN },
2318 		{ 0 }
2319 	};
2320 	static struct procunit_info default_info = {
2321 		0, NULL, default_value_info
2322 	};
2323 	const char *name = extension_unit ?
2324 		"Extension Unit" : "Processing Unit";
2325 
2326 	if (desc->bLength < 13) {
2327 		usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid);
2328 		return -EINVAL;
2329 	}
2330 
2331 	num_ins = desc->bNrInPins;
2332 	if (desc->bLength < 13 + num_ins ||
2333 	    desc->bLength < num_ins + uac_processing_unit_bControlSize(desc, state->mixer->protocol)) {
2334 		usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid);
2335 		return -EINVAL;
2336 	}
2337 
2338 	for (i = 0; i < num_ins; i++) {
2339 		err = parse_audio_unit(state, desc->baSourceID[i]);
2340 		if (err < 0)
2341 			return err;
2342 	}
2343 
2344 	type = le16_to_cpu(desc->wProcessType);
2345 	for (info = list; info && info->type; info++)
2346 		if (info->type == type)
2347 			break;
2348 	if (!info || !info->type)
2349 		info = &default_info;
2350 
2351 	for (valinfo = info->values; valinfo->control; valinfo++) {
2352 		__u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);
2353 
2354 		if (state->mixer->protocol == UAC_VERSION_1) {
2355 			if (!(controls[valinfo->control / 8] &
2356 					(1 << ((valinfo->control % 8) - 1))))
2357 				continue;
2358 		} else { /* UAC_VERSION_2/3 */
2359 			if (!uac_v2v3_control_is_readable(controls[valinfo->control / 8],
2360 							  valinfo->control))
2361 				continue;
2362 		}
2363 
2364 		map = find_map(state->map, unitid, valinfo->control);
2365 		if (check_ignored_ctl(map))
2366 			continue;
2367 		cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2368 		if (!cval)
2369 			return -ENOMEM;
2370 		snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2371 		cval->control = valinfo->control;
2372 		cval->val_type = valinfo->val_type;
2373 		cval->channels = 1;
2374 
2375 		if (state->mixer->protocol > UAC_VERSION_1 &&
2376 		    !uac_v2v3_control_is_writeable(controls[valinfo->control / 8],
2377 						   valinfo->control))
2378 			cval->master_readonly = 1;
2379 
2380 		/* get min/max values */
2381 		switch (type) {
2382 		case UAC_PROCESS_UP_DOWNMIX: {
2383 			bool mode_sel = false;
2384 
2385 			switch (state->mixer->protocol) {
2386 			case UAC_VERSION_1:
2387 			case UAC_VERSION_2:
2388 			default:
2389 				if (cval->control == UAC_UD_MODE_SELECT)
2390 					mode_sel = true;
2391 				break;
2392 			case UAC_VERSION_3:
2393 				if (cval->control == UAC3_UD_MODE_SELECT)
2394 					mode_sel = true;
2395 				break;
2396 			}
2397 
2398 			if (mode_sel) {
2399 				__u8 *control_spec = uac_processing_unit_specific(desc,
2400 								state->mixer->protocol);
2401 				cval->min = 1;
2402 				cval->max = control_spec[0];
2403 				cval->res = 1;
2404 				cval->initialized = 1;
2405 				break;
2406 			}
2407 
2408 			get_min_max(cval, valinfo->min_value);
2409 			break;
2410 		}
2411 		case USB_XU_CLOCK_RATE:
2412 			/*
2413 			 * E-Mu USB 0404/0202/TrackerPre/0204
2414 			 * samplerate control quirk
2415 			 */
2416 			cval->min = 0;
2417 			cval->max = 5;
2418 			cval->res = 1;
2419 			cval->initialized = 1;
2420 			break;
2421 		default:
2422 			get_min_max(cval, valinfo->min_value);
2423 			break;
2424 		}
2425 
2426 		kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
2427 		if (!kctl) {
2428 			kfree(cval);
2429 			return -ENOMEM;
2430 		}
2431 		kctl->private_free = snd_usb_mixer_elem_free;
2432 
2433 		if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name))) {
2434 			/* nothing */ ;
2435 		} else if (info->name) {
2436 			strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
2437 		} else {
2438 			if (extension_unit)
2439 				nameid = uac_extension_unit_iExtension(desc, state->mixer->protocol);
2440 			else
2441 				nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
2442 			len = 0;
2443 			if (nameid)
2444 				len = snd_usb_copy_string_desc(state->chip,
2445 							       nameid,
2446 							       kctl->id.name,
2447 							       sizeof(kctl->id.name));
2448 			if (!len)
2449 				strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
2450 		}
2451 		append_ctl_name(kctl, " ");
2452 		append_ctl_name(kctl, valinfo->suffix);
2453 
2454 		usb_audio_dbg(state->chip,
2455 			      "[%d] PU [%s] ch = %d, val = %d/%d\n",
2456 			      cval->head.id, kctl->id.name, cval->channels,
2457 			      cval->min, cval->max);
2458 
2459 		err = snd_usb_mixer_add_control(&cval->head, kctl);
2460 		if (err < 0)
2461 			return err;
2462 	}
2463 	return 0;
2464 }
2465 
2466 static int parse_audio_processing_unit(struct mixer_build *state, int unitid,
2467 				       void *raw_desc)
2468 {
2469 	switch (state->mixer->protocol) {
2470 	case UAC_VERSION_1:
2471 	case UAC_VERSION_2:
2472 	default:
2473 		return build_audio_procunit(state, unitid, raw_desc,
2474 					    procunits, false);
2475 	case UAC_VERSION_3:
2476 		return build_audio_procunit(state, unitid, raw_desc,
2477 					    uac3_procunits, false);
2478 	}
2479 }
2480 
2481 static int parse_audio_extension_unit(struct mixer_build *state, int unitid,
2482 				      void *raw_desc)
2483 {
2484 	/*
2485 	 * Note that we parse extension units with processing unit descriptors.
2486 	 * That's ok as the layout is the same.
2487 	 */
2488 	return build_audio_procunit(state, unitid, raw_desc, extunits, true);
2489 }
2490 
2491 /*
2492  * Selector Unit
2493  */
2494 
2495 /*
2496  * info callback for selector unit
2497  * use an enumerator type for routing
2498  */
2499 static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol,
2500 				   struct snd_ctl_elem_info *uinfo)
2501 {
2502 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2503 	const char **itemlist = (const char **)kcontrol->private_value;
2504 
2505 	if (snd_BUG_ON(!itemlist))
2506 		return -EINVAL;
2507 	return snd_ctl_enum_info(uinfo, 1, cval->max, itemlist);
2508 }
2509 
2510 /* get callback for selector unit */
2511 static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol,
2512 				  struct snd_ctl_elem_value *ucontrol)
2513 {
2514 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2515 	int val, err;
2516 
2517 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2518 	if (err < 0) {
2519 		ucontrol->value.enumerated.item[0] = 0;
2520 		return filter_error(cval, err);
2521 	}
2522 	val = get_relative_value(cval, val);
2523 	ucontrol->value.enumerated.item[0] = val;
2524 	return 0;
2525 }
2526 
2527 /* put callback for selector unit */
2528 static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol,
2529 				  struct snd_ctl_elem_value *ucontrol)
2530 {
2531 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2532 	int val, oval, err;
2533 
2534 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2535 	if (err < 0)
2536 		return filter_error(cval, err);
2537 	val = ucontrol->value.enumerated.item[0];
2538 	val = get_abs_value(cval, val);
2539 	if (val != oval) {
2540 		set_cur_ctl_value(cval, cval->control << 8, val);
2541 		return 1;
2542 	}
2543 	return 0;
2544 }
2545 
2546 /* alsa control interface for selector unit */
2547 static const struct snd_kcontrol_new mixer_selectunit_ctl = {
2548 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2549 	.name = "", /* will be filled later */
2550 	.info = mixer_ctl_selector_info,
2551 	.get = mixer_ctl_selector_get,
2552 	.put = mixer_ctl_selector_put,
2553 };
2554 
2555 /*
2556  * private free callback.
2557  * free both private_data and private_value
2558  */
2559 static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
2560 {
2561 	int i, num_ins = 0;
2562 
2563 	if (kctl->private_data) {
2564 		struct usb_mixer_elem_info *cval = kctl->private_data;
2565 		num_ins = cval->max;
2566 		kfree(cval);
2567 		kctl->private_data = NULL;
2568 	}
2569 	if (kctl->private_value) {
2570 		char **itemlist = (char **)kctl->private_value;
2571 		for (i = 0; i < num_ins; i++)
2572 			kfree(itemlist[i]);
2573 		kfree(itemlist);
2574 		kctl->private_value = 0;
2575 	}
2576 }
2577 
2578 /*
2579  * parse a selector unit
2580  */
2581 static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
2582 				     void *raw_desc)
2583 {
2584 	struct uac_selector_unit_descriptor *desc = raw_desc;
2585 	unsigned int i, nameid, len;
2586 	int err;
2587 	struct usb_mixer_elem_info *cval;
2588 	struct snd_kcontrol *kctl;
2589 	const struct usbmix_name_map *map;
2590 	char **namelist;
2591 
2592 	if (desc->bLength < 5 || !desc->bNrInPins ||
2593 	    desc->bLength < 5 + desc->bNrInPins) {
2594 		usb_audio_err(state->chip,
2595 			"invalid SELECTOR UNIT descriptor %d\n", unitid);
2596 		return -EINVAL;
2597 	}
2598 
2599 	for (i = 0; i < desc->bNrInPins; i++) {
2600 		err = parse_audio_unit(state, desc->baSourceID[i]);
2601 		if (err < 0)
2602 			return err;
2603 	}
2604 
2605 	if (desc->bNrInPins == 1) /* only one ? nonsense! */
2606 		return 0;
2607 
2608 	map = find_map(state->map, unitid, 0);
2609 	if (check_ignored_ctl(map))
2610 		return 0;
2611 
2612 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2613 	if (!cval)
2614 		return -ENOMEM;
2615 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2616 	cval->val_type = USB_MIXER_U8;
2617 	cval->channels = 1;
2618 	cval->min = 1;
2619 	cval->max = desc->bNrInPins;
2620 	cval->res = 1;
2621 	cval->initialized = 1;
2622 
2623 	switch (state->mixer->protocol) {
2624 	case UAC_VERSION_1:
2625 	default:
2626 		cval->control = 0;
2627 		break;
2628 	case UAC_VERSION_2:
2629 	case UAC_VERSION_3:
2630 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
2631 		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
2632 			cval->control = UAC2_CX_CLOCK_SELECTOR;
2633 		else /* UAC2/3_SELECTOR_UNIT */
2634 			cval->control = UAC2_SU_SELECTOR;
2635 		break;
2636 	}
2637 
2638 	namelist = kmalloc_array(desc->bNrInPins, sizeof(char *), GFP_KERNEL);
2639 	if (!namelist) {
2640 		kfree(cval);
2641 		return -ENOMEM;
2642 	}
2643 #define MAX_ITEM_NAME_LEN	64
2644 	for (i = 0; i < desc->bNrInPins; i++) {
2645 		struct usb_audio_term iterm;
2646 		len = 0;
2647 		namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
2648 		if (!namelist[i]) {
2649 			while (i--)
2650 				kfree(namelist[i]);
2651 			kfree(namelist);
2652 			kfree(cval);
2653 			return -ENOMEM;
2654 		}
2655 		len = check_mapped_selector_name(state, unitid, i, namelist[i],
2656 						 MAX_ITEM_NAME_LEN);
2657 		if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
2658 			len = get_term_name(state->chip, &iterm, namelist[i],
2659 					    MAX_ITEM_NAME_LEN, 0);
2660 		if (! len)
2661 			sprintf(namelist[i], "Input %u", i);
2662 	}
2663 
2664 	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
2665 	if (! kctl) {
2666 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2667 		for (i = 0; i < desc->bNrInPins; i++)
2668 			kfree(namelist[i]);
2669 		kfree(namelist);
2670 		kfree(cval);
2671 		return -ENOMEM;
2672 	}
2673 	kctl->private_value = (unsigned long)namelist;
2674 	kctl->private_free = usb_mixer_selector_elem_free;
2675 
2676 	/* check the static mapping table at first */
2677 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2678 	if (!len) {
2679 		/* no mapping ? */
2680 		switch (state->mixer->protocol) {
2681 		case UAC_VERSION_1:
2682 		case UAC_VERSION_2:
2683 		default:
2684 		/* if iSelector is given, use it */
2685 			nameid = uac_selector_unit_iSelector(desc);
2686 			if (nameid)
2687 				len = snd_usb_copy_string_desc(state->chip,
2688 							nameid, kctl->id.name,
2689 							sizeof(kctl->id.name));
2690 			break;
2691 		case UAC_VERSION_3:
2692 			/* TODO: Class-Specific strings not yet supported */
2693 			break;
2694 		}
2695 
2696 		/* ... or pick up the terminal name at next */
2697 		if (!len)
2698 			len = get_term_name(state->chip, &state->oterm,
2699 				    kctl->id.name, sizeof(kctl->id.name), 0);
2700 		/* ... or use the fixed string "USB" as the last resort */
2701 		if (!len)
2702 			strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
2703 
2704 		/* and add the proper suffix */
2705 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR ||
2706 		    desc->bDescriptorSubtype == UAC3_CLOCK_SELECTOR)
2707 			append_ctl_name(kctl, " Clock Source");
2708 		else if ((state->oterm.type & 0xff00) == 0x0100)
2709 			append_ctl_name(kctl, " Capture Source");
2710 		else
2711 			append_ctl_name(kctl, " Playback Source");
2712 	}
2713 
2714 	usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
2715 		    cval->head.id, kctl->id.name, desc->bNrInPins);
2716 	return snd_usb_mixer_add_control(&cval->head, kctl);
2717 }
2718 
2719 /*
2720  * parse an audio unit recursively
2721  */
2722 
2723 static int parse_audio_unit(struct mixer_build *state, int unitid)
2724 {
2725 	unsigned char *p1;
2726 	int protocol = state->mixer->protocol;
2727 
2728 	if (test_and_set_bit(unitid, state->unitbitmap))
2729 		return 0; /* the unit already visited */
2730 
2731 	p1 = find_audio_control_unit(state, unitid);
2732 	if (!p1) {
2733 		usb_audio_err(state->chip, "unit %d not found!\n", unitid);
2734 		return -EINVAL;
2735 	}
2736 
2737 	if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {
2738 		switch (p1[2]) {
2739 		case UAC_INPUT_TERMINAL:
2740 			return parse_audio_input_terminal(state, unitid, p1);
2741 		case UAC_MIXER_UNIT:
2742 			return parse_audio_mixer_unit(state, unitid, p1);
2743 		case UAC2_CLOCK_SOURCE:
2744 			return parse_clock_source_unit(state, unitid, p1);
2745 		case UAC_SELECTOR_UNIT:
2746 		case UAC2_CLOCK_SELECTOR:
2747 			return parse_audio_selector_unit(state, unitid, p1);
2748 		case UAC_FEATURE_UNIT:
2749 			return parse_audio_feature_unit(state, unitid, p1);
2750 		case UAC1_PROCESSING_UNIT:
2751 		/*   UAC2_EFFECT_UNIT has the same value */
2752 			if (protocol == UAC_VERSION_1)
2753 				return parse_audio_processing_unit(state, unitid, p1);
2754 			else
2755 				return 0; /* FIXME - effect units not implemented yet */
2756 		case UAC1_EXTENSION_UNIT:
2757 		/*   UAC2_PROCESSING_UNIT_V2 has the same value */
2758 			if (protocol == UAC_VERSION_1)
2759 				return parse_audio_extension_unit(state, unitid, p1);
2760 			else /* UAC_VERSION_2 */
2761 				return parse_audio_processing_unit(state, unitid, p1);
2762 		case UAC2_EXTENSION_UNIT_V2:
2763 			return parse_audio_extension_unit(state, unitid, p1);
2764 		default:
2765 			usb_audio_err(state->chip,
2766 				"unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
2767 			return -EINVAL;
2768 		}
2769 	} else { /* UAC_VERSION_3 */
2770 		switch (p1[2]) {
2771 		case UAC_INPUT_TERMINAL:
2772 			return parse_audio_input_terminal(state, unitid, p1);
2773 		case UAC3_MIXER_UNIT:
2774 			return parse_audio_mixer_unit(state, unitid, p1);
2775 		case UAC3_CLOCK_SOURCE:
2776 			return parse_clock_source_unit(state, unitid, p1);
2777 		case UAC3_SELECTOR_UNIT:
2778 		case UAC3_CLOCK_SELECTOR:
2779 			return parse_audio_selector_unit(state, unitid, p1);
2780 		case UAC3_FEATURE_UNIT:
2781 			return parse_audio_feature_unit(state, unitid, p1);
2782 		case UAC3_EFFECT_UNIT:
2783 			return 0; /* FIXME - effect units not implemented yet */
2784 		case UAC3_PROCESSING_UNIT:
2785 			return parse_audio_processing_unit(state, unitid, p1);
2786 		case UAC3_EXTENSION_UNIT:
2787 			return parse_audio_extension_unit(state, unitid, p1);
2788 		default:
2789 			usb_audio_err(state->chip,
2790 				"unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
2791 			return -EINVAL;
2792 		}
2793 	}
2794 }
2795 
2796 static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
2797 {
2798 	/* kill pending URBs */
2799 	snd_usb_mixer_disconnect(mixer);
2800 
2801 	kfree(mixer->id_elems);
2802 	if (mixer->urb) {
2803 		kfree(mixer->urb->transfer_buffer);
2804 		usb_free_urb(mixer->urb);
2805 	}
2806 	usb_free_urb(mixer->rc_urb);
2807 	kfree(mixer->rc_setup_packet);
2808 	kfree(mixer);
2809 }
2810 
2811 static int snd_usb_mixer_dev_free(struct snd_device *device)
2812 {
2813 	struct usb_mixer_interface *mixer = device->device_data;
2814 	snd_usb_mixer_free(mixer);
2815 	return 0;
2816 }
2817 
2818 /* UAC3 predefined channels configuration */
2819 struct uac3_badd_profile {
2820 	int subclass;
2821 	const char *name;
2822 	int c_chmask;	/* capture channels mask */
2823 	int p_chmask;	/* playback channels mask */
2824 	int st_chmask;	/* side tone mixing channel mask */
2825 };
2826 
2827 static struct uac3_badd_profile uac3_badd_profiles[] = {
2828 	{
2829 		/*
2830 		 * BAIF, BAOF or combination of both
2831 		 * IN: Mono or Stereo cfg, Mono alt possible
2832 		 * OUT: Mono or Stereo cfg, Mono alt possible
2833 		 */
2834 		.subclass = UAC3_FUNCTION_SUBCLASS_GENERIC_IO,
2835 		.name = "GENERIC IO",
2836 		.c_chmask = -1,		/* dynamic channels */
2837 		.p_chmask = -1,		/* dynamic channels */
2838 	},
2839 	{
2840 		/* BAOF; Stereo only cfg, Mono alt possible */
2841 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADPHONE,
2842 		.name = "HEADPHONE",
2843 		.p_chmask = 3,
2844 	},
2845 	{
2846 		/* BAOF; Mono or Stereo cfg, Mono alt possible */
2847 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKER,
2848 		.name = "SPEAKER",
2849 		.p_chmask = -1,		/* dynamic channels */
2850 	},
2851 	{
2852 		/* BAIF; Mono or Stereo cfg, Mono alt possible */
2853 		.subclass = UAC3_FUNCTION_SUBCLASS_MICROPHONE,
2854 		.name = "MICROPHONE",
2855 		.c_chmask = -1,		/* dynamic channels */
2856 	},
2857 	{
2858 		/*
2859 		 * BAIOF topology
2860 		 * IN: Mono only
2861 		 * OUT: Mono or Stereo cfg, Mono alt possible
2862 		 */
2863 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET,
2864 		.name = "HEADSET",
2865 		.c_chmask = 1,
2866 		.p_chmask = -1,		/* dynamic channels */
2867 		.st_chmask = 1,
2868 	},
2869 	{
2870 		/* BAIOF; IN: Mono only; OUT: Stereo only, Mono alt possible */
2871 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER,
2872 		.name = "HEADSET ADAPTER",
2873 		.c_chmask = 1,
2874 		.p_chmask = 3,
2875 		.st_chmask = 1,
2876 	},
2877 	{
2878 		/* BAIF + BAOF; IN: Mono only; OUT: Mono only */
2879 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE,
2880 		.name = "SPEAKERPHONE",
2881 		.c_chmask = 1,
2882 		.p_chmask = 1,
2883 	},
2884 	{ 0 } /* terminator */
2885 };
2886 
2887 static bool uac3_badd_func_has_valid_channels(struct usb_mixer_interface *mixer,
2888 					      struct uac3_badd_profile *f,
2889 					      int c_chmask, int p_chmask)
2890 {
2891 	/*
2892 	 * If both playback/capture channels are dynamic, make sure
2893 	 * at least one channel is present
2894 	 */
2895 	if (f->c_chmask < 0 && f->p_chmask < 0) {
2896 		if (!c_chmask && !p_chmask) {
2897 			usb_audio_warn(mixer->chip, "BAAD %s: no channels?",
2898 				       f->name);
2899 			return false;
2900 		}
2901 		return true;
2902 	}
2903 
2904 	if ((f->c_chmask < 0 && !c_chmask) ||
2905 	    (f->c_chmask >= 0 && f->c_chmask != c_chmask)) {
2906 		usb_audio_warn(mixer->chip, "BAAD %s c_chmask mismatch",
2907 			       f->name);
2908 		return false;
2909 	}
2910 	if ((f->p_chmask < 0 && !p_chmask) ||
2911 	    (f->p_chmask >= 0 && f->p_chmask != p_chmask)) {
2912 		usb_audio_warn(mixer->chip, "BAAD %s p_chmask mismatch",
2913 			       f->name);
2914 		return false;
2915 	}
2916 	return true;
2917 }
2918 
2919 /*
2920  * create mixer controls for UAC3 BADD profiles
2921  *
2922  * UAC3 BADD device doesn't contain CS descriptors thus we will guess everything
2923  *
2924  * BADD device may contain Mixer Unit, which doesn't have any controls, skip it
2925  */
2926 static int snd_usb_mixer_controls_badd(struct usb_mixer_interface *mixer,
2927 				       int ctrlif)
2928 {
2929 	struct usb_device *dev = mixer->chip->dev;
2930 	struct usb_interface_assoc_descriptor *assoc;
2931 	int badd_profile = mixer->chip->badd_profile;
2932 	struct uac3_badd_profile *f;
2933 	const struct usbmix_ctl_map *map;
2934 	int p_chmask = 0, c_chmask = 0, st_chmask = 0;
2935 	int i;
2936 
2937 	assoc = usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
2938 
2939 	/* Detect BADD capture/playback channels from AS EP descriptors */
2940 	for (i = 0; i < assoc->bInterfaceCount; i++) {
2941 		int intf = assoc->bFirstInterface + i;
2942 
2943 		struct usb_interface *iface;
2944 		struct usb_host_interface *alts;
2945 		struct usb_interface_descriptor *altsd;
2946 		unsigned int maxpacksize;
2947 		char dir_in;
2948 		int chmask, num;
2949 
2950 		if (intf == ctrlif)
2951 			continue;
2952 
2953 		iface = usb_ifnum_to_if(dev, intf);
2954 		num = iface->num_altsetting;
2955 
2956 		if (num < 2)
2957 			return -EINVAL;
2958 
2959 		/*
2960 		 * The number of Channels in an AudioStreaming interface
2961 		 * and the audio sample bit resolution (16 bits or 24
2962 		 * bits) can be derived from the wMaxPacketSize field in
2963 		 * the Standard AS Audio Data Endpoint descriptor in
2964 		 * Alternate Setting 1
2965 		 */
2966 		alts = &iface->altsetting[1];
2967 		altsd = get_iface_desc(alts);
2968 
2969 		if (altsd->bNumEndpoints < 1)
2970 			return -EINVAL;
2971 
2972 		/* check direction */
2973 		dir_in = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN);
2974 		maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
2975 
2976 		switch (maxpacksize) {
2977 		default:
2978 			usb_audio_err(mixer->chip,
2979 				"incorrect wMaxPacketSize 0x%x for BADD profile\n",
2980 				maxpacksize);
2981 			return -EINVAL;
2982 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_16:
2983 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_16:
2984 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_24:
2985 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_24:
2986 			chmask = 1;
2987 			break;
2988 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_16:
2989 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_16:
2990 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_24:
2991 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_24:
2992 			chmask = 3;
2993 			break;
2994 		}
2995 
2996 		if (dir_in)
2997 			c_chmask = chmask;
2998 		else
2999 			p_chmask = chmask;
3000 	}
3001 
3002 	usb_audio_dbg(mixer->chip,
3003 		"UAC3 BADD profile 0x%x: detected c_chmask=%d p_chmask=%d\n",
3004 		badd_profile, c_chmask, p_chmask);
3005 
3006 	/* check the mapping table */
3007 	for (map = uac3_badd_usbmix_ctl_maps; map->id; map++) {
3008 		if (map->id == badd_profile)
3009 			break;
3010 	}
3011 
3012 	if (!map->id)
3013 		return -EINVAL;
3014 
3015 	for (f = uac3_badd_profiles; f->name; f++) {
3016 		if (badd_profile == f->subclass)
3017 			break;
3018 	}
3019 	if (!f->name)
3020 		return -EINVAL;
3021 	if (!uac3_badd_func_has_valid_channels(mixer, f, c_chmask, p_chmask))
3022 		return -EINVAL;
3023 	st_chmask = f->st_chmask;
3024 
3025 	/* Playback */
3026 	if (p_chmask) {
3027 		/* Master channel, always writable */
3028 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3029 				       UAC3_BADD_FU_ID2, map->map);
3030 		/* Mono/Stereo volume channels, always writable */
3031 		build_feature_ctl_badd(mixer, p_chmask, UAC_FU_VOLUME,
3032 				       UAC3_BADD_FU_ID2, map->map);
3033 	}
3034 
3035 	/* Capture */
3036 	if (c_chmask) {
3037 		/* Master channel, always writable */
3038 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3039 				       UAC3_BADD_FU_ID5, map->map);
3040 		/* Mono/Stereo volume channels, always writable */
3041 		build_feature_ctl_badd(mixer, c_chmask, UAC_FU_VOLUME,
3042 				       UAC3_BADD_FU_ID5, map->map);
3043 	}
3044 
3045 	/* Side tone-mixing */
3046 	if (st_chmask) {
3047 		/* Master channel, always writable */
3048 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
3049 				       UAC3_BADD_FU_ID7, map->map);
3050 		/* Mono volume channel, always writable */
3051 		build_feature_ctl_badd(mixer, 1, UAC_FU_VOLUME,
3052 				       UAC3_BADD_FU_ID7, map->map);
3053 	}
3054 
3055 	/* Insertion Control */
3056 	if (f->subclass == UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER) {
3057 		struct usb_audio_term iterm, oterm;
3058 
3059 		/* Input Term - Insertion control */
3060 		memset(&iterm, 0, sizeof(iterm));
3061 		iterm.id = UAC3_BADD_IT_ID4;
3062 		iterm.type = UAC_BIDIR_TERMINAL_HEADSET;
3063 		build_connector_control(mixer, &iterm, true);
3064 
3065 		/* Output Term - Insertion control */
3066 		memset(&oterm, 0, sizeof(oterm));
3067 		oterm.id = UAC3_BADD_OT_ID3;
3068 		oterm.type = UAC_BIDIR_TERMINAL_HEADSET;
3069 		build_connector_control(mixer, &oterm, false);
3070 	}
3071 
3072 	return 0;
3073 }
3074 
3075 /*
3076  * create mixer controls
3077  *
3078  * walk through all UAC_OUTPUT_TERMINAL descriptors to search for mixers
3079  */
3080 static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
3081 {
3082 	struct mixer_build state;
3083 	int err;
3084 	const struct usbmix_ctl_map *map;
3085 	void *p;
3086 
3087 	memset(&state, 0, sizeof(state));
3088 	state.chip = mixer->chip;
3089 	state.mixer = mixer;
3090 	state.buffer = mixer->hostif->extra;
3091 	state.buflen = mixer->hostif->extralen;
3092 
3093 	/* check the mapping table */
3094 	for (map = usbmix_ctl_maps; map->id; map++) {
3095 		if (map->id == state.chip->usb_id) {
3096 			state.map = map->map;
3097 			state.selector_map = map->selector_map;
3098 			mixer->ignore_ctl_error = map->ignore_ctl_error;
3099 			break;
3100 		}
3101 	}
3102 
3103 	p = NULL;
3104 	while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
3105 					    mixer->hostif->extralen,
3106 					    p, UAC_OUTPUT_TERMINAL)) != NULL) {
3107 		if (mixer->protocol == UAC_VERSION_1) {
3108 			struct uac1_output_terminal_descriptor *desc = p;
3109 
3110 			if (desc->bLength < sizeof(*desc))
3111 				continue; /* invalid descriptor? */
3112 			/* mark terminal ID as visited */
3113 			set_bit(desc->bTerminalID, state.unitbitmap);
3114 			state.oterm.id = desc->bTerminalID;
3115 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3116 			state.oterm.name = desc->iTerminal;
3117 			err = parse_audio_unit(&state, desc->bSourceID);
3118 			if (err < 0 && err != -EINVAL)
3119 				return err;
3120 		} else if (mixer->protocol == UAC_VERSION_2) {
3121 			struct uac2_output_terminal_descriptor *desc = p;
3122 
3123 			if (desc->bLength < sizeof(*desc))
3124 				continue; /* invalid descriptor? */
3125 			/* mark terminal ID as visited */
3126 			set_bit(desc->bTerminalID, state.unitbitmap);
3127 			state.oterm.id = desc->bTerminalID;
3128 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3129 			state.oterm.name = desc->iTerminal;
3130 			err = parse_audio_unit(&state, desc->bSourceID);
3131 			if (err < 0 && err != -EINVAL)
3132 				return err;
3133 
3134 			/*
3135 			 * For UAC2, use the same approach to also add the
3136 			 * clock selectors
3137 			 */
3138 			err = parse_audio_unit(&state, desc->bCSourceID);
3139 			if (err < 0 && err != -EINVAL)
3140 				return err;
3141 
3142 			if (uac_v2v3_control_is_readable(le16_to_cpu(desc->bmControls),
3143 							 UAC2_TE_CONNECTOR)) {
3144 				build_connector_control(state.mixer, &state.oterm,
3145 							false);
3146 			}
3147 		} else {  /* UAC_VERSION_3 */
3148 			struct uac3_output_terminal_descriptor *desc = p;
3149 
3150 			if (desc->bLength < sizeof(*desc))
3151 				continue; /* invalid descriptor? */
3152 			/* mark terminal ID as visited */
3153 			set_bit(desc->bTerminalID, state.unitbitmap);
3154 			state.oterm.id = desc->bTerminalID;
3155 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3156 			state.oterm.name = le16_to_cpu(desc->wTerminalDescrStr);
3157 			err = parse_audio_unit(&state, desc->bSourceID);
3158 			if (err < 0 && err != -EINVAL)
3159 				return err;
3160 
3161 			/*
3162 			 * For UAC3, use the same approach to also add the
3163 			 * clock selectors
3164 			 */
3165 			err = parse_audio_unit(&state, desc->bCSourceID);
3166 			if (err < 0 && err != -EINVAL)
3167 				return err;
3168 
3169 			if (uac_v2v3_control_is_readable(le32_to_cpu(desc->bmControls),
3170 							 UAC3_TE_INSERTION)) {
3171 				build_connector_control(state.mixer, &state.oterm,
3172 							false);
3173 			}
3174 		}
3175 	}
3176 
3177 	return 0;
3178 }
3179 
3180 void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
3181 {
3182 	struct usb_mixer_elem_list *list;
3183 
3184 	for_each_mixer_elem(list, mixer, unitid) {
3185 		struct usb_mixer_elem_info *info =
3186 			mixer_elem_list_to_info(list);
3187 		/* invalidate cache, so the value is read from the device */
3188 		info->cached = 0;
3189 		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3190 			       &list->kctl->id);
3191 	}
3192 }
3193 
3194 static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
3195 				    struct usb_mixer_elem_list *list)
3196 {
3197 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3198 	static char *val_types[] = {"BOOLEAN", "INV_BOOLEAN",
3199 				    "S8", "U8", "S16", "U16"};
3200 	snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
3201 			    "channels=%i, type=\"%s\"\n", cval->head.id,
3202 			    cval->control, cval->cmask, cval->channels,
3203 			    val_types[cval->val_type]);
3204 	snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
3205 			    cval->min, cval->max, cval->dBmin, cval->dBmax);
3206 }
3207 
3208 static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
3209 				    struct snd_info_buffer *buffer)
3210 {
3211 	struct snd_usb_audio *chip = entry->private_data;
3212 	struct usb_mixer_interface *mixer;
3213 	struct usb_mixer_elem_list *list;
3214 	int unitid;
3215 
3216 	list_for_each_entry(mixer, &chip->mixer_list, list) {
3217 		snd_iprintf(buffer,
3218 			"USB Mixer: usb_id=0x%08x, ctrlif=%i, ctlerr=%i\n",
3219 				chip->usb_id, snd_usb_ctrl_intf(chip),
3220 				mixer->ignore_ctl_error);
3221 		snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
3222 		for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
3223 			for_each_mixer_elem(list, mixer, unitid) {
3224 				snd_iprintf(buffer, "  Unit: %i\n", list->id);
3225 				if (list->kctl)
3226 					snd_iprintf(buffer,
3227 						    "    Control: name=\"%s\", index=%i\n",
3228 						    list->kctl->id.name,
3229 						    list->kctl->id.index);
3230 				if (list->dump)
3231 					list->dump(buffer, list);
3232 			}
3233 		}
3234 	}
3235 }
3236 
3237 static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
3238 				       int attribute, int value, int index)
3239 {
3240 	struct usb_mixer_elem_list *list;
3241 	__u8 unitid = (index >> 8) & 0xff;
3242 	__u8 control = (value >> 8) & 0xff;
3243 	__u8 channel = value & 0xff;
3244 	unsigned int count = 0;
3245 
3246 	if (channel >= MAX_CHANNELS) {
3247 		usb_audio_dbg(mixer->chip,
3248 			"%s(): bogus channel number %d\n",
3249 			__func__, channel);
3250 		return;
3251 	}
3252 
3253 	for_each_mixer_elem(list, mixer, unitid)
3254 		count++;
3255 
3256 	if (count == 0)
3257 		return;
3258 
3259 	for_each_mixer_elem(list, mixer, unitid) {
3260 		struct usb_mixer_elem_info *info;
3261 
3262 		if (!list->kctl)
3263 			continue;
3264 
3265 		info = mixer_elem_list_to_info(list);
3266 		if (count > 1 && info->control != control)
3267 			continue;
3268 
3269 		switch (attribute) {
3270 		case UAC2_CS_CUR:
3271 			/* invalidate cache, so the value is read from the device */
3272 			if (channel)
3273 				info->cached &= ~(1 << channel);
3274 			else /* master channel */
3275 				info->cached = 0;
3276 
3277 			snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3278 				       &info->head.kctl->id);
3279 			break;
3280 
3281 		case UAC2_CS_RANGE:
3282 			/* TODO */
3283 			break;
3284 
3285 		case UAC2_CS_MEM:
3286 			/* TODO */
3287 			break;
3288 
3289 		default:
3290 			usb_audio_dbg(mixer->chip,
3291 				"unknown attribute %d in interrupt\n",
3292 				attribute);
3293 			break;
3294 		} /* switch */
3295 	}
3296 }
3297 
3298 static void snd_usb_mixer_interrupt(struct urb *urb)
3299 {
3300 	struct usb_mixer_interface *mixer = urb->context;
3301 	int len = urb->actual_length;
3302 	int ustatus = urb->status;
3303 
3304 	if (ustatus != 0)
3305 		goto requeue;
3306 
3307 	if (mixer->protocol == UAC_VERSION_1) {
3308 		struct uac1_status_word *status;
3309 
3310 		for (status = urb->transfer_buffer;
3311 		     len >= sizeof(*status);
3312 		     len -= sizeof(*status), status++) {
3313 			dev_dbg(&urb->dev->dev, "status interrupt: %02x %02x\n",
3314 						status->bStatusType,
3315 						status->bOriginator);
3316 
3317 			/* ignore any notifications not from the control interface */
3318 			if ((status->bStatusType & UAC1_STATUS_TYPE_ORIG_MASK) !=
3319 				UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF)
3320 				continue;
3321 
3322 			if (status->bStatusType & UAC1_STATUS_TYPE_MEM_CHANGED)
3323 				snd_usb_mixer_rc_memory_change(mixer, status->bOriginator);
3324 			else
3325 				snd_usb_mixer_notify_id(mixer, status->bOriginator);
3326 		}
3327 	} else { /* UAC_VERSION_2 */
3328 		struct uac2_interrupt_data_msg *msg;
3329 
3330 		for (msg = urb->transfer_buffer;
3331 		     len >= sizeof(*msg);
3332 		     len -= sizeof(*msg), msg++) {
3333 			/* drop vendor specific and endpoint requests */
3334 			if ((msg->bInfo & UAC2_INTERRUPT_DATA_MSG_VENDOR) ||
3335 			    (msg->bInfo & UAC2_INTERRUPT_DATA_MSG_EP))
3336 				continue;
3337 
3338 			snd_usb_mixer_interrupt_v2(mixer, msg->bAttribute,
3339 						   le16_to_cpu(msg->wValue),
3340 						   le16_to_cpu(msg->wIndex));
3341 		}
3342 	}
3343 
3344 requeue:
3345 	if (ustatus != -ENOENT &&
3346 	    ustatus != -ECONNRESET &&
3347 	    ustatus != -ESHUTDOWN) {
3348 		urb->dev = mixer->chip->dev;
3349 		usb_submit_urb(urb, GFP_ATOMIC);
3350 	}
3351 }
3352 
3353 /* create the handler for the optional status interrupt endpoint */
3354 static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
3355 {
3356 	struct usb_endpoint_descriptor *ep;
3357 	void *transfer_buffer;
3358 	int buffer_length;
3359 	unsigned int epnum;
3360 
3361 	/* we need one interrupt input endpoint */
3362 	if (get_iface_desc(mixer->hostif)->bNumEndpoints < 1)
3363 		return 0;
3364 	ep = get_endpoint(mixer->hostif, 0);
3365 	if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_int(ep))
3366 		return 0;
3367 
3368 	epnum = usb_endpoint_num(ep);
3369 	buffer_length = le16_to_cpu(ep->wMaxPacketSize);
3370 	transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
3371 	if (!transfer_buffer)
3372 		return -ENOMEM;
3373 	mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
3374 	if (!mixer->urb) {
3375 		kfree(transfer_buffer);
3376 		return -ENOMEM;
3377 	}
3378 	usb_fill_int_urb(mixer->urb, mixer->chip->dev,
3379 			 usb_rcvintpipe(mixer->chip->dev, epnum),
3380 			 transfer_buffer, buffer_length,
3381 			 snd_usb_mixer_interrupt, mixer, ep->bInterval);
3382 	usb_submit_urb(mixer->urb, GFP_KERNEL);
3383 	return 0;
3384 }
3385 
3386 static int keep_iface_ctl_get(struct snd_kcontrol *kcontrol,
3387 			      struct snd_ctl_elem_value *ucontrol)
3388 {
3389 	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
3390 
3391 	ucontrol->value.integer.value[0] = mixer->chip->keep_iface;
3392 	return 0;
3393 }
3394 
3395 static int keep_iface_ctl_put(struct snd_kcontrol *kcontrol,
3396 			      struct snd_ctl_elem_value *ucontrol)
3397 {
3398 	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
3399 	bool keep_iface = !!ucontrol->value.integer.value[0];
3400 
3401 	if (mixer->chip->keep_iface == keep_iface)
3402 		return 0;
3403 	mixer->chip->keep_iface = keep_iface;
3404 	return 1;
3405 }
3406 
3407 static const struct snd_kcontrol_new keep_iface_ctl = {
3408 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
3409 	.name = "Keep Interface",
3410 	.info = snd_ctl_boolean_mono_info,
3411 	.get = keep_iface_ctl_get,
3412 	.put = keep_iface_ctl_put,
3413 };
3414 
3415 static int create_keep_iface_ctl(struct usb_mixer_interface *mixer)
3416 {
3417 	struct snd_kcontrol *kctl = snd_ctl_new1(&keep_iface_ctl, mixer);
3418 
3419 	/* need only one control per card */
3420 	if (snd_ctl_find_id(mixer->chip->card, &kctl->id)) {
3421 		snd_ctl_free_one(kctl);
3422 		return 0;
3423 	}
3424 
3425 	return snd_ctl_add(mixer->chip->card, kctl);
3426 }
3427 
3428 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
3429 			 int ignore_error)
3430 {
3431 	static struct snd_device_ops dev_ops = {
3432 		.dev_free = snd_usb_mixer_dev_free
3433 	};
3434 	struct usb_mixer_interface *mixer;
3435 	int err;
3436 
3437 	strcpy(chip->card->mixername, "USB Mixer");
3438 
3439 	mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
3440 	if (!mixer)
3441 		return -ENOMEM;
3442 	mixer->chip = chip;
3443 	mixer->ignore_ctl_error = ignore_error;
3444 	mixer->id_elems = kcalloc(MAX_ID_ELEMS, sizeof(*mixer->id_elems),
3445 				  GFP_KERNEL);
3446 	if (!mixer->id_elems) {
3447 		kfree(mixer);
3448 		return -ENOMEM;
3449 	}
3450 
3451 	mixer->hostif = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
3452 	switch (get_iface_desc(mixer->hostif)->bInterfaceProtocol) {
3453 	case UAC_VERSION_1:
3454 	default:
3455 		mixer->protocol = UAC_VERSION_1;
3456 		break;
3457 	case UAC_VERSION_2:
3458 		mixer->protocol = UAC_VERSION_2;
3459 		break;
3460 	case UAC_VERSION_3:
3461 		mixer->protocol = UAC_VERSION_3;
3462 		break;
3463 	}
3464 
3465 	if (mixer->protocol == UAC_VERSION_3 &&
3466 			chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
3467 		err = snd_usb_mixer_controls_badd(mixer, ctrlif);
3468 		if (err < 0)
3469 			goto _error;
3470 	} else {
3471 		err = snd_usb_mixer_controls(mixer);
3472 		if (err < 0)
3473 			goto _error;
3474 	}
3475 
3476 	err = snd_usb_mixer_status_create(mixer);
3477 	if (err < 0)
3478 		goto _error;
3479 
3480 	err = create_keep_iface_ctl(mixer);
3481 	if (err < 0)
3482 		goto _error;
3483 
3484 	err = snd_usb_mixer_apply_create_quirk(mixer);
3485 	if (err < 0)
3486 		goto _error;
3487 
3488 	err = snd_device_new(chip->card, SNDRV_DEV_CODEC, mixer, &dev_ops);
3489 	if (err < 0)
3490 		goto _error;
3491 
3492 	if (list_empty(&chip->mixer_list))
3493 		snd_card_ro_proc_new(chip->card, "usbmixer", chip,
3494 				     snd_usb_mixer_proc_read);
3495 
3496 	list_add(&mixer->list, &chip->mixer_list);
3497 	return 0;
3498 
3499 _error:
3500 	snd_usb_mixer_free(mixer);
3501 	return err;
3502 }
3503 
3504 void snd_usb_mixer_disconnect(struct usb_mixer_interface *mixer)
3505 {
3506 	if (mixer->disconnected)
3507 		return;
3508 	if (mixer->urb)
3509 		usb_kill_urb(mixer->urb);
3510 	if (mixer->rc_urb)
3511 		usb_kill_urb(mixer->rc_urb);
3512 	mixer->disconnected = true;
3513 }
3514 
3515 #ifdef CONFIG_PM
3516 /* stop any bus activity of a mixer */
3517 static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
3518 {
3519 	usb_kill_urb(mixer->urb);
3520 	usb_kill_urb(mixer->rc_urb);
3521 }
3522 
3523 static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
3524 {
3525 	int err;
3526 
3527 	if (mixer->urb) {
3528 		err = usb_submit_urb(mixer->urb, GFP_NOIO);
3529 		if (err < 0)
3530 			return err;
3531 	}
3532 
3533 	return 0;
3534 }
3535 
3536 int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
3537 {
3538 	snd_usb_mixer_inactivate(mixer);
3539 	return 0;
3540 }
3541 
3542 static int restore_mixer_value(struct usb_mixer_elem_list *list)
3543 {
3544 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3545 	int c, err, idx;
3546 
3547 	if (cval->cmask) {
3548 		idx = 0;
3549 		for (c = 0; c < MAX_CHANNELS; c++) {
3550 			if (!(cval->cmask & (1 << c)))
3551 				continue;
3552 			if (cval->cached & (1 << (c + 1))) {
3553 				err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
3554 							cval->cache_val[idx]);
3555 				if (err < 0)
3556 					return err;
3557 			}
3558 			idx++;
3559 		}
3560 	} else {
3561 		/* master */
3562 		if (cval->cached) {
3563 			err = snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
3564 			if (err < 0)
3565 				return err;
3566 		}
3567 	}
3568 
3569 	return 0;
3570 }
3571 
3572 int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume)
3573 {
3574 	struct usb_mixer_elem_list *list;
3575 	int id, err;
3576 
3577 	if (reset_resume) {
3578 		/* restore cached mixer values */
3579 		for (id = 0; id < MAX_ID_ELEMS; id++) {
3580 			for_each_mixer_elem(list, mixer, id) {
3581 				if (list->resume) {
3582 					err = list->resume(list);
3583 					if (err < 0)
3584 						return err;
3585 				}
3586 			}
3587 		}
3588 	}
3589 
3590 	snd_usb_mixer_resume_quirk(mixer);
3591 
3592 	return snd_usb_mixer_activate(mixer);
3593 }
3594 #endif
3595 
3596 void snd_usb_mixer_elem_init_std(struct usb_mixer_elem_list *list,
3597 				 struct usb_mixer_interface *mixer,
3598 				 int unitid)
3599 {
3600 	list->mixer = mixer;
3601 	list->id = unitid;
3602 	list->dump = snd_usb_mixer_dump_cval;
3603 #ifdef CONFIG_PM
3604 	list->resume = restore_mixer_value;
3605 #endif
3606 }
3607