xref: /openbmc/linux/sound/usb/mixer.c (revision 3d624617)
1 /*
2  *   (Tentative) USB Audio Driver for ALSA
3  *
4  *   Mixer control part
5  *
6  *   Copyright (c) 2002 by Takashi Iwai <tiwai@suse.de>
7  *
8  *   Many codes borrowed from audio.c by
9  *	    Alan Cox (alan@lxorguk.ukuu.org.uk)
10  *	    Thomas Sailer (sailer@ife.ee.ethz.ch)
11  *
12  *
13  *   This program is free software; you can redistribute it and/or modify
14  *   it under the terms of the GNU General Public License as published by
15  *   the Free Software Foundation; either version 2 of the License, or
16  *   (at your option) any later version.
17  *
18  *   This program is distributed in the hope that it will be useful,
19  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
20  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  *   GNU General Public License for more details.
22  *
23  *   You should have received a copy of the GNU General Public License
24  *   along with this program; if not, write to the Free Software
25  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
26  *
27  */
28 
29 /*
30  * TODOs, for both the mixer and the streaming interfaces:
31  *
32  *  - support for UAC2 effect units
33  *  - support for graphical equalizers
34  *  - RANGE and MEM set commands (UAC2)
35  *  - RANGE and MEM interrupt dispatchers (UAC2)
36  *  - audio channel clustering (UAC2)
37  *  - audio sample rate converter units (UAC2)
38  *  - proper handling of clock multipliers (UAC2)
39  *  - dispatch clock change notifications (UAC2)
40  *  	- stop PCM streams which use a clock that became invalid
41  *  	- stop PCM streams which use a clock selector that has changed
42  *  	- parse available sample rates again when clock sources changed
43  */
44 
45 #include <linux/bitops.h>
46 #include <linux/init.h>
47 #include <linux/list.h>
48 #include <linux/log2.h>
49 #include <linux/slab.h>
50 #include <linux/string.h>
51 #include <linux/usb.h>
52 #include <linux/usb/audio.h>
53 #include <linux/usb/audio-v2.h>
54 #include <linux/usb/audio-v3.h>
55 
56 #include <sound/core.h>
57 #include <sound/control.h>
58 #include <sound/hwdep.h>
59 #include <sound/info.h>
60 #include <sound/tlv.h>
61 
62 #include "usbaudio.h"
63 #include "mixer.h"
64 #include "helper.h"
65 #include "mixer_quirks.h"
66 #include "power.h"
67 
68 #define MAX_ID_ELEMS	256
69 
70 struct usb_audio_term {
71 	int id;
72 	int type;
73 	int channels;
74 	unsigned int chconfig;
75 	int name;
76 };
77 
78 struct usbmix_name_map;
79 
80 struct mixer_build {
81 	struct snd_usb_audio *chip;
82 	struct usb_mixer_interface *mixer;
83 	unsigned char *buffer;
84 	unsigned int buflen;
85 	DECLARE_BITMAP(unitbitmap, MAX_ID_ELEMS);
86 	struct usb_audio_term oterm;
87 	const struct usbmix_name_map *map;
88 	const struct usbmix_selector_map *selector_map;
89 };
90 
91 /*E-mu 0202/0404/0204 eXtension Unit(XU) control*/
92 enum {
93 	USB_XU_CLOCK_RATE 		= 0xe301,
94 	USB_XU_CLOCK_SOURCE		= 0xe302,
95 	USB_XU_DIGITAL_IO_STATUS	= 0xe303,
96 	USB_XU_DEVICE_OPTIONS		= 0xe304,
97 	USB_XU_DIRECT_MONITORING	= 0xe305,
98 	USB_XU_METERING			= 0xe306
99 };
100 enum {
101 	USB_XU_CLOCK_SOURCE_SELECTOR = 0x02,	/* clock source*/
102 	USB_XU_CLOCK_RATE_SELECTOR = 0x03,	/* clock rate */
103 	USB_XU_DIGITAL_FORMAT_SELECTOR = 0x01,	/* the spdif format */
104 	USB_XU_SOFT_LIMIT_SELECTOR = 0x03	/* soft limiter */
105 };
106 
107 /*
108  * manual mapping of mixer names
109  * if the mixer topology is too complicated and the parsed names are
110  * ambiguous, add the entries in usbmixer_maps.c.
111  */
112 #include "mixer_maps.c"
113 
114 static const struct usbmix_name_map *
115 find_map(const struct usbmix_name_map *p, int unitid, int control)
116 {
117 	if (!p)
118 		return NULL;
119 
120 	for (; p->id; p++) {
121 		if (p->id == unitid &&
122 		    (!control || !p->control || control == p->control))
123 			return p;
124 	}
125 	return NULL;
126 }
127 
128 /* get the mapped name if the unit matches */
129 static int
130 check_mapped_name(const struct usbmix_name_map *p, char *buf, int buflen)
131 {
132 	if (!p || !p->name)
133 		return 0;
134 
135 	buflen--;
136 	return strlcpy(buf, p->name, buflen);
137 }
138 
139 /* ignore the error value if ignore_ctl_error flag is set */
140 #define filter_error(cval, err) \
141 	((cval)->head.mixer->ignore_ctl_error ? 0 : (err))
142 
143 /* check whether the control should be ignored */
144 static inline int
145 check_ignored_ctl(const struct usbmix_name_map *p)
146 {
147 	if (!p || p->name || p->dB)
148 		return 0;
149 	return 1;
150 }
151 
152 /* dB mapping */
153 static inline void check_mapped_dB(const struct usbmix_name_map *p,
154 				   struct usb_mixer_elem_info *cval)
155 {
156 	if (p && p->dB) {
157 		cval->dBmin = p->dB->min;
158 		cval->dBmax = p->dB->max;
159 		cval->initialized = 1;
160 	}
161 }
162 
163 /* get the mapped selector source name */
164 static int check_mapped_selector_name(struct mixer_build *state, int unitid,
165 				      int index, char *buf, int buflen)
166 {
167 	const struct usbmix_selector_map *p;
168 
169 	if (!state->selector_map)
170 		return 0;
171 	for (p = state->selector_map; p->id; p++) {
172 		if (p->id == unitid && index < p->count)
173 			return strlcpy(buf, p->names[index], buflen);
174 	}
175 	return 0;
176 }
177 
178 /*
179  * find an audio control unit with the given unit id
180  */
181 static void *find_audio_control_unit(struct mixer_build *state,
182 				     unsigned char unit)
183 {
184 	/* we just parse the header */
185 	struct uac_feature_unit_descriptor *hdr = NULL;
186 
187 	while ((hdr = snd_usb_find_desc(state->buffer, state->buflen, hdr,
188 					USB_DT_CS_INTERFACE)) != NULL) {
189 		if (hdr->bLength >= 4 &&
190 		    hdr->bDescriptorSubtype >= UAC_INPUT_TERMINAL &&
191 		    hdr->bDescriptorSubtype <= UAC3_SAMPLE_RATE_CONVERTER &&
192 		    hdr->bUnitID == unit)
193 			return hdr;
194 	}
195 
196 	return NULL;
197 }
198 
199 /*
200  * copy a string with the given id
201  */
202 static int snd_usb_copy_string_desc(struct snd_usb_audio *chip,
203 				    int index, char *buf, int maxlen)
204 {
205 	int len = usb_string(chip->dev, index, buf, maxlen - 1);
206 
207 	if (len < 0)
208 		return 0;
209 
210 	buf[len] = 0;
211 	return len;
212 }
213 
214 /*
215  * convert from the byte/word on usb descriptor to the zero-based integer
216  */
217 static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
218 {
219 	switch (cval->val_type) {
220 	case USB_MIXER_BOOLEAN:
221 		return !!val;
222 	case USB_MIXER_INV_BOOLEAN:
223 		return !val;
224 	case USB_MIXER_U8:
225 		val &= 0xff;
226 		break;
227 	case USB_MIXER_S8:
228 		val &= 0xff;
229 		if (val >= 0x80)
230 			val -= 0x100;
231 		break;
232 	case USB_MIXER_U16:
233 		val &= 0xffff;
234 		break;
235 	case USB_MIXER_S16:
236 		val &= 0xffff;
237 		if (val >= 0x8000)
238 			val -= 0x10000;
239 		break;
240 	}
241 	return val;
242 }
243 
244 /*
245  * convert from the zero-based int to the byte/word for usb descriptor
246  */
247 static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
248 {
249 	switch (cval->val_type) {
250 	case USB_MIXER_BOOLEAN:
251 		return !!val;
252 	case USB_MIXER_INV_BOOLEAN:
253 		return !val;
254 	case USB_MIXER_S8:
255 	case USB_MIXER_U8:
256 		return val & 0xff;
257 	case USB_MIXER_S16:
258 	case USB_MIXER_U16:
259 		return val & 0xffff;
260 	}
261 	return 0; /* not reached */
262 }
263 
264 static int get_relative_value(struct usb_mixer_elem_info *cval, int val)
265 {
266 	if (!cval->res)
267 		cval->res = 1;
268 	if (val < cval->min)
269 		return 0;
270 	else if (val >= cval->max)
271 		return (cval->max - cval->min + cval->res - 1) / cval->res;
272 	else
273 		return (val - cval->min) / cval->res;
274 }
275 
276 static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
277 {
278 	if (val < 0)
279 		return cval->min;
280 	if (!cval->res)
281 		cval->res = 1;
282 	val *= cval->res;
283 	val += cval->min;
284 	if (val > cval->max)
285 		return cval->max;
286 	return val;
287 }
288 
289 static int uac2_ctl_value_size(int val_type)
290 {
291 	switch (val_type) {
292 	case USB_MIXER_S32:
293 	case USB_MIXER_U32:
294 		return 4;
295 	case USB_MIXER_S16:
296 	case USB_MIXER_U16:
297 		return 2;
298 	default:
299 		return 1;
300 	}
301 	return 0; /* unreachable */
302 }
303 
304 
305 /*
306  * retrieve a mixer value
307  */
308 
309 static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request,
310 			    int validx, int *value_ret)
311 {
312 	struct snd_usb_audio *chip = cval->head.mixer->chip;
313 	unsigned char buf[2];
314 	int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
315 	int timeout = 10;
316 	int idx = 0, err;
317 
318 	err = snd_usb_lock_shutdown(chip);
319 	if (err < 0)
320 		return -EIO;
321 
322 	while (timeout-- > 0) {
323 		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
324 		err = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
325 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
326 				      validx, idx, buf, val_len);
327 		if (err >= val_len) {
328 			*value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
329 			err = 0;
330 			goto out;
331 		} else if (err == -ETIMEDOUT) {
332 			goto out;
333 		}
334 	}
335 	usb_audio_dbg(chip,
336 		"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
337 		request, validx, idx, cval->val_type);
338 	err = -EINVAL;
339 
340  out:
341 	snd_usb_unlock_shutdown(chip);
342 	return err;
343 }
344 
345 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
346 			    int validx, int *value_ret)
347 {
348 	struct snd_usb_audio *chip = cval->head.mixer->chip;
349 	/* enough space for one range */
350 	unsigned char buf[sizeof(__u16) + 3 * sizeof(__u32)];
351 	unsigned char *val;
352 	int idx = 0, ret, val_size, size;
353 	__u8 bRequest;
354 
355 	val_size = uac2_ctl_value_size(cval->val_type);
356 
357 	if (request == UAC_GET_CUR) {
358 		bRequest = UAC2_CS_CUR;
359 		size = val_size;
360 	} else {
361 		bRequest = UAC2_CS_RANGE;
362 		size = sizeof(__u16) + 3 * val_size;
363 	}
364 
365 	memset(buf, 0, sizeof(buf));
366 
367 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
368 	if (ret)
369 		goto error;
370 
371 	idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
372 	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
373 			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
374 			      validx, idx, buf, size);
375 	snd_usb_unlock_shutdown(chip);
376 
377 	if (ret < 0) {
378 error:
379 		usb_audio_err(chip,
380 			"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
381 			request, validx, idx, cval->val_type);
382 		return ret;
383 	}
384 
385 	/* FIXME: how should we handle multiple triplets here? */
386 
387 	switch (request) {
388 	case UAC_GET_CUR:
389 		val = buf;
390 		break;
391 	case UAC_GET_MIN:
392 		val = buf + sizeof(__u16);
393 		break;
394 	case UAC_GET_MAX:
395 		val = buf + sizeof(__u16) + val_size;
396 		break;
397 	case UAC_GET_RES:
398 		val = buf + sizeof(__u16) + val_size * 2;
399 		break;
400 	default:
401 		return -EINVAL;
402 	}
403 
404 	*value_ret = convert_signed_value(cval,
405 					  snd_usb_combine_bytes(val, val_size));
406 
407 	return 0;
408 }
409 
410 static int get_ctl_value(struct usb_mixer_elem_info *cval, int request,
411 			 int validx, int *value_ret)
412 {
413 	validx += cval->idx_off;
414 
415 	return (cval->head.mixer->protocol == UAC_VERSION_1) ?
416 		get_ctl_value_v1(cval, request, validx, value_ret) :
417 		get_ctl_value_v2(cval, request, validx, value_ret);
418 }
419 
420 static int get_cur_ctl_value(struct usb_mixer_elem_info *cval,
421 			     int validx, int *value)
422 {
423 	return get_ctl_value(cval, UAC_GET_CUR, validx, value);
424 }
425 
426 /* channel = 0: master, 1 = first channel */
427 static inline int get_cur_mix_raw(struct usb_mixer_elem_info *cval,
428 				  int channel, int *value)
429 {
430 	return get_ctl_value(cval, UAC_GET_CUR,
431 			     (cval->control << 8) | channel,
432 			     value);
433 }
434 
435 int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
436 			     int channel, int index, int *value)
437 {
438 	int err;
439 
440 	if (cval->cached & (1 << channel)) {
441 		*value = cval->cache_val[index];
442 		return 0;
443 	}
444 	err = get_cur_mix_raw(cval, channel, value);
445 	if (err < 0) {
446 		if (!cval->head.mixer->ignore_ctl_error)
447 			usb_audio_dbg(cval->head.mixer->chip,
448 				"cannot get current value for control %d ch %d: err = %d\n",
449 				      cval->control, channel, err);
450 		return err;
451 	}
452 	cval->cached |= 1 << channel;
453 	cval->cache_val[index] = *value;
454 	return 0;
455 }
456 
457 /*
458  * set a mixer value
459  */
460 
461 int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
462 				int request, int validx, int value_set)
463 {
464 	struct snd_usb_audio *chip = cval->head.mixer->chip;
465 	unsigned char buf[4];
466 	int idx = 0, val_len, err, timeout = 10;
467 
468 	validx += cval->idx_off;
469 
470 
471 	if (cval->head.mixer->protocol == UAC_VERSION_1) {
472 		val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
473 	} else { /* UAC_VERSION_2/3 */
474 		val_len = uac2_ctl_value_size(cval->val_type);
475 
476 		/* FIXME */
477 		if (request != UAC_SET_CUR) {
478 			usb_audio_dbg(chip, "RANGE setting not yet supported\n");
479 			return -EINVAL;
480 		}
481 
482 		request = UAC2_CS_CUR;
483 	}
484 
485 	value_set = convert_bytes_value(cval, value_set);
486 	buf[0] = value_set & 0xff;
487 	buf[1] = (value_set >> 8) & 0xff;
488 	buf[2] = (value_set >> 16) & 0xff;
489 	buf[3] = (value_set >> 24) & 0xff;
490 
491 	err = snd_usb_lock_shutdown(chip);
492 	if (err < 0)
493 		return -EIO;
494 
495 	while (timeout-- > 0) {
496 		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
497 		err = snd_usb_ctl_msg(chip->dev,
498 				      usb_sndctrlpipe(chip->dev, 0), request,
499 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
500 				      validx, idx, buf, val_len);
501 		if (err >= 0) {
502 			err = 0;
503 			goto out;
504 		} else if (err == -ETIMEDOUT) {
505 			goto out;
506 		}
507 	}
508 	usb_audio_dbg(chip, "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
509 		      request, validx, idx, cval->val_type, buf[0], buf[1]);
510 	err = -EINVAL;
511 
512  out:
513 	snd_usb_unlock_shutdown(chip);
514 	return err;
515 }
516 
517 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval,
518 			     int validx, int value)
519 {
520 	return snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, validx, value);
521 }
522 
523 int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
524 			     int index, int value)
525 {
526 	int err;
527 	unsigned int read_only = (channel == 0) ?
528 		cval->master_readonly :
529 		cval->ch_readonly & (1 << (channel - 1));
530 
531 	if (read_only) {
532 		usb_audio_dbg(cval->head.mixer->chip,
533 			      "%s(): channel %d of control %d is read_only\n",
534 			    __func__, channel, cval->control);
535 		return 0;
536 	}
537 
538 	err = snd_usb_mixer_set_ctl_value(cval,
539 					  UAC_SET_CUR, (cval->control << 8) | channel,
540 					  value);
541 	if (err < 0)
542 		return err;
543 	cval->cached |= 1 << channel;
544 	cval->cache_val[index] = value;
545 	return 0;
546 }
547 
548 /*
549  * TLV callback for mixer volume controls
550  */
551 int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
552 			 unsigned int size, unsigned int __user *_tlv)
553 {
554 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
555 	DECLARE_TLV_DB_MINMAX(scale, 0, 0);
556 
557 	if (size < sizeof(scale))
558 		return -ENOMEM;
559 	if (cval->min_mute)
560 		scale[0] = SNDRV_CTL_TLVT_DB_MINMAX_MUTE;
561 	scale[2] = cval->dBmin;
562 	scale[3] = cval->dBmax;
563 	if (copy_to_user(_tlv, scale, sizeof(scale)))
564 		return -EFAULT;
565 	return 0;
566 }
567 
568 /*
569  * parser routines begin here...
570  */
571 
572 static int parse_audio_unit(struct mixer_build *state, int unitid);
573 
574 
575 /*
576  * check if the input/output channel routing is enabled on the given bitmap.
577  * used for mixer unit parser
578  */
579 static int check_matrix_bitmap(unsigned char *bmap,
580 			       int ich, int och, int num_outs)
581 {
582 	int idx = ich * num_outs + och;
583 	return bmap[idx >> 3] & (0x80 >> (idx & 7));
584 }
585 
586 /*
587  * add an alsa control element
588  * search and increment the index until an empty slot is found.
589  *
590  * if failed, give up and free the control instance.
591  */
592 
593 int snd_usb_mixer_add_control(struct usb_mixer_elem_list *list,
594 			      struct snd_kcontrol *kctl)
595 {
596 	struct usb_mixer_interface *mixer = list->mixer;
597 	int err;
598 
599 	while (snd_ctl_find_id(mixer->chip->card, &kctl->id))
600 		kctl->id.index++;
601 	if ((err = snd_ctl_add(mixer->chip->card, kctl)) < 0) {
602 		usb_audio_dbg(mixer->chip, "cannot add control (err = %d)\n",
603 			      err);
604 		return err;
605 	}
606 	list->kctl = kctl;
607 	list->next_id_elem = mixer->id_elems[list->id];
608 	mixer->id_elems[list->id] = list;
609 	return 0;
610 }
611 
612 /*
613  * get a terminal name string
614  */
615 
616 static struct iterm_name_combo {
617 	int type;
618 	char *name;
619 } iterm_names[] = {
620 	{ 0x0300, "Output" },
621 	{ 0x0301, "Speaker" },
622 	{ 0x0302, "Headphone" },
623 	{ 0x0303, "HMD Audio" },
624 	{ 0x0304, "Desktop Speaker" },
625 	{ 0x0305, "Room Speaker" },
626 	{ 0x0306, "Com Speaker" },
627 	{ 0x0307, "LFE" },
628 	{ 0x0600, "External In" },
629 	{ 0x0601, "Analog In" },
630 	{ 0x0602, "Digital In" },
631 	{ 0x0603, "Line" },
632 	{ 0x0604, "Legacy In" },
633 	{ 0x0605, "IEC958 In" },
634 	{ 0x0606, "1394 DA Stream" },
635 	{ 0x0607, "1394 DV Stream" },
636 	{ 0x0700, "Embedded" },
637 	{ 0x0701, "Noise Source" },
638 	{ 0x0702, "Equalization Noise" },
639 	{ 0x0703, "CD" },
640 	{ 0x0704, "DAT" },
641 	{ 0x0705, "DCC" },
642 	{ 0x0706, "MiniDisk" },
643 	{ 0x0707, "Analog Tape" },
644 	{ 0x0708, "Phonograph" },
645 	{ 0x0709, "VCR Audio" },
646 	{ 0x070a, "Video Disk Audio" },
647 	{ 0x070b, "DVD Audio" },
648 	{ 0x070c, "TV Tuner Audio" },
649 	{ 0x070d, "Satellite Rec Audio" },
650 	{ 0x070e, "Cable Tuner Audio" },
651 	{ 0x070f, "DSS Audio" },
652 	{ 0x0710, "Radio Receiver" },
653 	{ 0x0711, "Radio Transmitter" },
654 	{ 0x0712, "Multi-Track Recorder" },
655 	{ 0x0713, "Synthesizer" },
656 	{ 0 },
657 };
658 
659 static int get_term_name(struct snd_usb_audio *chip, struct usb_audio_term *iterm,
660 			 unsigned char *name, int maxlen, int term_only)
661 {
662 	struct iterm_name_combo *names;
663 	int len;
664 
665 	if (iterm->name) {
666 		len = snd_usb_copy_string_desc(chip, iterm->name,
667 						name, maxlen);
668 		if (len)
669 			return len;
670 	}
671 
672 	/* virtual type - not a real terminal */
673 	if (iterm->type >> 16) {
674 		if (term_only)
675 			return 0;
676 		switch (iterm->type >> 16) {
677 		case UAC_SELECTOR_UNIT:
678 			strcpy(name, "Selector");
679 			return 8;
680 		case UAC1_PROCESSING_UNIT:
681 			strcpy(name, "Process Unit");
682 			return 12;
683 		case UAC1_EXTENSION_UNIT:
684 			strcpy(name, "Ext Unit");
685 			return 8;
686 		case UAC_MIXER_UNIT:
687 			strcpy(name, "Mixer");
688 			return 5;
689 		default:
690 			return sprintf(name, "Unit %d", iterm->id);
691 		}
692 	}
693 
694 	switch (iterm->type & 0xff00) {
695 	case 0x0100:
696 		strcpy(name, "PCM");
697 		return 3;
698 	case 0x0200:
699 		strcpy(name, "Mic");
700 		return 3;
701 	case 0x0400:
702 		strcpy(name, "Headset");
703 		return 7;
704 	case 0x0500:
705 		strcpy(name, "Phone");
706 		return 5;
707 	}
708 
709 	for (names = iterm_names; names->type; names++) {
710 		if (names->type == iterm->type) {
711 			strcpy(name, names->name);
712 			return strlen(names->name);
713 		}
714 	}
715 
716 	return 0;
717 }
718 
719 /*
720  * Get logical cluster information for UAC3 devices.
721  */
722 static int get_cluster_channels_v3(struct mixer_build *state, unsigned int cluster_id)
723 {
724 	struct uac3_cluster_header_descriptor c_header;
725 	int err;
726 
727 	err = snd_usb_ctl_msg(state->chip->dev,
728 			usb_rcvctrlpipe(state->chip->dev, 0),
729 			UAC3_CS_REQ_HIGH_CAPABILITY_DESCRIPTOR,
730 			USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
731 			cluster_id,
732 			snd_usb_ctrl_intf(state->chip),
733 			&c_header, sizeof(c_header));
734 	if (err < 0)
735 		goto error;
736 	if (err != sizeof(c_header)) {
737 		err = -EIO;
738 		goto error;
739 	}
740 
741 	return c_header.bNrChannels;
742 
743 error:
744 	usb_audio_err(state->chip, "cannot request logical cluster ID: %d (err: %d)\n", cluster_id, err);
745 	return err;
746 }
747 
748 /*
749  * Get number of channels for a Mixer Unit.
750  */
751 static int uac_mixer_unit_get_channels(struct mixer_build *state,
752 				       struct uac_mixer_unit_descriptor *desc)
753 {
754 	int mu_channels;
755 
756 	if (desc->bLength < 11)
757 		return -EINVAL;
758 	if (!desc->bNrInPins)
759 		return -EINVAL;
760 
761 	switch (state->mixer->protocol) {
762 	case UAC_VERSION_1:
763 	case UAC_VERSION_2:
764 	default:
765 		mu_channels = uac_mixer_unit_bNrChannels(desc);
766 		break;
767 	case UAC_VERSION_3:
768 		mu_channels = get_cluster_channels_v3(state,
769 				uac3_mixer_unit_wClusterDescrID(desc));
770 		break;
771 	}
772 
773 	if (!mu_channels)
774 		return -EINVAL;
775 
776 	return mu_channels;
777 }
778 
779 /*
780  * parse the source unit recursively until it reaches to a terminal
781  * or a branched unit.
782  */
783 static int check_input_term(struct mixer_build *state, int id,
784 			    struct usb_audio_term *term)
785 {
786 	int protocol = state->mixer->protocol;
787 	int err;
788 	void *p1;
789 
790 	memset(term, 0, sizeof(*term));
791 	while ((p1 = find_audio_control_unit(state, id)) != NULL) {
792 		unsigned char *hdr = p1;
793 		term->id = id;
794 
795 		if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {
796 			switch (hdr[2]) {
797 			case UAC_INPUT_TERMINAL:
798 				if (protocol == UAC_VERSION_1) {
799 					struct uac_input_terminal_descriptor *d = p1;
800 
801 					term->type = le16_to_cpu(d->wTerminalType);
802 					term->channels = d->bNrChannels;
803 					term->chconfig = le16_to_cpu(d->wChannelConfig);
804 					term->name = d->iTerminal;
805 				} else { /* UAC_VERSION_2 */
806 					struct uac2_input_terminal_descriptor *d = p1;
807 
808 					/* call recursively to verify that the
809 					 * referenced clock entity is valid */
810 					err = check_input_term(state, d->bCSourceID, term);
811 					if (err < 0)
812 						return err;
813 
814 					/* save input term properties after recursion,
815 					 * to ensure they are not overriden by the
816 					 * recursion calls */
817 					term->id = id;
818 					term->type = le16_to_cpu(d->wTerminalType);
819 					term->channels = d->bNrChannels;
820 					term->chconfig = le32_to_cpu(d->bmChannelConfig);
821 					term->name = d->iTerminal;
822 				}
823 				return 0;
824 			case UAC_FEATURE_UNIT: {
825 				/* the header is the same for v1 and v2 */
826 				struct uac_feature_unit_descriptor *d = p1;
827 
828 				id = d->bSourceID;
829 				break; /* continue to parse */
830 			}
831 			case UAC_MIXER_UNIT: {
832 				struct uac_mixer_unit_descriptor *d = p1;
833 
834 				term->type = d->bDescriptorSubtype << 16; /* virtual type */
835 				term->channels = uac_mixer_unit_bNrChannels(d);
836 				term->chconfig = uac_mixer_unit_wChannelConfig(d, protocol);
837 				term->name = uac_mixer_unit_iMixer(d);
838 				return 0;
839 			}
840 			case UAC_SELECTOR_UNIT:
841 			case UAC2_CLOCK_SELECTOR: {
842 				struct uac_selector_unit_descriptor *d = p1;
843 				/* call recursively to retrieve the channel info */
844 				err = check_input_term(state, d->baSourceID[0], term);
845 				if (err < 0)
846 					return err;
847 				term->type = d->bDescriptorSubtype << 16; /* virtual type */
848 				term->id = id;
849 				term->name = uac_selector_unit_iSelector(d);
850 				return 0;
851 			}
852 			case UAC1_PROCESSING_UNIT:
853 			case UAC1_EXTENSION_UNIT:
854 			/* UAC2_PROCESSING_UNIT_V2 */
855 			/* UAC2_EFFECT_UNIT */
856 			case UAC2_EXTENSION_UNIT_V2: {
857 				struct uac_processing_unit_descriptor *d = p1;
858 
859 				if (protocol == UAC_VERSION_2 &&
860 					hdr[2] == UAC2_EFFECT_UNIT) {
861 					/* UAC2/UAC1 unit IDs overlap here in an
862 					 * uncompatible way. Ignore this unit for now.
863 					 */
864 					return 0;
865 				}
866 
867 				if (d->bNrInPins) {
868 					id = d->baSourceID[0];
869 					break; /* continue to parse */
870 				}
871 				term->type = d->bDescriptorSubtype << 16; /* virtual type */
872 				term->channels = uac_processing_unit_bNrChannels(d);
873 				term->chconfig = uac_processing_unit_wChannelConfig(d, protocol);
874 				term->name = uac_processing_unit_iProcessing(d, protocol);
875 				return 0;
876 			}
877 			case UAC2_CLOCK_SOURCE: {
878 				struct uac_clock_source_descriptor *d = p1;
879 
880 				term->type = d->bDescriptorSubtype << 16; /* virtual type */
881 				term->id = id;
882 				term->name = d->iClockSource;
883 				return 0;
884 			}
885 			default:
886 				return -ENODEV;
887 			}
888 		} else { /* UAC_VERSION_3 */
889 			switch (hdr[2]) {
890 			case UAC_INPUT_TERMINAL: {
891 				struct uac3_input_terminal_descriptor *d = p1;
892 
893 				/* call recursively to verify that the
894 				 * referenced clock entity is valid */
895 				err = check_input_term(state, d->bCSourceID, term);
896 				if (err < 0)
897 					return err;
898 
899 				/* save input term properties after recursion,
900 				 * to ensure they are not overriden by the
901 				 * recursion calls */
902 				term->id = id;
903 				term->type = le16_to_cpu(d->wTerminalType);
904 
905 				err = get_cluster_channels_v3(state, le16_to_cpu(d->wClusterDescrID));
906 				if (err < 0)
907 					return err;
908 				term->channels = err;
909 
910 				/* REVISIT: UAC3 IT doesn't have channels cfg */
911 				term->chconfig = 0;
912 
913 				term->name = le16_to_cpu(d->wTerminalDescrStr);
914 				return 0;
915 			}
916 			case UAC3_FEATURE_UNIT: {
917 				struct uac3_feature_unit_descriptor *d = p1;
918 
919 				id = d->bSourceID;
920 				break; /* continue to parse */
921 			}
922 			case UAC3_CLOCK_SOURCE: {
923 				struct uac3_clock_source_descriptor *d = p1;
924 
925 				term->type = d->bDescriptorSubtype << 16; /* virtual type */
926 				term->id = id;
927 				term->name = le16_to_cpu(d->wClockSourceStr);
928 				return 0;
929 			}
930 			case UAC3_MIXER_UNIT: {
931 				struct uac_mixer_unit_descriptor *d = p1;
932 
933 				err = uac_mixer_unit_get_channels(state, d);
934 				if (err < 0)
935 					return err;
936 
937 				term->channels = err;
938 				term->type = d->bDescriptorSubtype << 16; /* virtual type */
939 
940 				return 0;
941 			}
942 			default:
943 				return -ENODEV;
944 			}
945 		}
946 	}
947 	return -ENODEV;
948 }
949 
950 /*
951  * Feature Unit
952  */
953 
954 /* feature unit control information */
955 struct usb_feature_control_info {
956 	int control;
957 	const char *name;
958 	int type;	/* data type for uac1 */
959 	int type_uac2;	/* data type for uac2 if different from uac1, else -1 */
960 };
961 
962 static struct usb_feature_control_info audio_feature_info[] = {
963 	{ UAC_FU_MUTE,			"Mute",			USB_MIXER_INV_BOOLEAN, -1 },
964 	{ UAC_FU_VOLUME,		"Volume",		USB_MIXER_S16, -1 },
965 	{ UAC_FU_BASS,			"Tone Control - Bass",	USB_MIXER_S8, -1 },
966 	{ UAC_FU_MID,			"Tone Control - Mid",	USB_MIXER_S8, -1 },
967 	{ UAC_FU_TREBLE,		"Tone Control - Treble", USB_MIXER_S8, -1 },
968 	{ UAC_FU_GRAPHIC_EQUALIZER,	"Graphic Equalizer",	USB_MIXER_S8, -1 }, /* FIXME: not implemented yet */
969 	{ UAC_FU_AUTOMATIC_GAIN,	"Auto Gain Control",	USB_MIXER_BOOLEAN, -1 },
970 	{ UAC_FU_DELAY,			"Delay Control",	USB_MIXER_U16, USB_MIXER_U32 },
971 	{ UAC_FU_BASS_BOOST,		"Bass Boost",		USB_MIXER_BOOLEAN, -1 },
972 	{ UAC_FU_LOUDNESS,		"Loudness",		USB_MIXER_BOOLEAN, -1 },
973 	/* UAC2 specific */
974 	{ UAC2_FU_INPUT_GAIN,		"Input Gain Control",	USB_MIXER_S16, -1 },
975 	{ UAC2_FU_INPUT_GAIN_PAD,	"Input Gain Pad Control", USB_MIXER_S16, -1 },
976 	{ UAC2_FU_PHASE_INVERTER,	 "Phase Inverter Control", USB_MIXER_BOOLEAN, -1 },
977 };
978 
979 /* private_free callback */
980 void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
981 {
982 	kfree(kctl->private_data);
983 	kctl->private_data = NULL;
984 }
985 
986 /*
987  * interface to ALSA control for feature/mixer units
988  */
989 
990 /* volume control quirks */
991 static void volume_control_quirks(struct usb_mixer_elem_info *cval,
992 				  struct snd_kcontrol *kctl)
993 {
994 	struct snd_usb_audio *chip = cval->head.mixer->chip;
995 	switch (chip->usb_id) {
996 	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
997 	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
998 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
999 			cval->min = 0x0000;
1000 			cval->max = 0xffff;
1001 			cval->res = 0x00e6;
1002 			break;
1003 		}
1004 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1005 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1006 			cval->min = 0x00;
1007 			cval->max = 0xff;
1008 			break;
1009 		}
1010 		if (strstr(kctl->id.name, "Effect Return") != NULL) {
1011 			cval->min = 0xb706;
1012 			cval->max = 0xff7b;
1013 			cval->res = 0x0073;
1014 			break;
1015 		}
1016 		if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
1017 			(strstr(kctl->id.name, "Effect Send") != NULL)) {
1018 			cval->min = 0xb5fb; /* -73 dB = 0xb6ff */
1019 			cval->max = 0xfcfe;
1020 			cval->res = 0x0073;
1021 		}
1022 		break;
1023 
1024 	case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */
1025 	case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
1026 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
1027 			usb_audio_info(chip,
1028 				       "set quirk for FTU Effect Duration\n");
1029 			cval->min = 0x0000;
1030 			cval->max = 0x7f00;
1031 			cval->res = 0x0100;
1032 			break;
1033 		}
1034 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
1035 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
1036 			usb_audio_info(chip,
1037 				       "set quirks for FTU Effect Feedback/Volume\n");
1038 			cval->min = 0x00;
1039 			cval->max = 0x7f;
1040 			break;
1041 		}
1042 		break;
1043 
1044 	case USB_ID(0x0d8c, 0x0103):
1045 		if (!strcmp(kctl->id.name, "PCM Playback Volume")) {
1046 			usb_audio_info(chip,
1047 				 "set volume quirk for CM102-A+/102S+\n");
1048 			cval->min = -256;
1049 		}
1050 		break;
1051 
1052 	case USB_ID(0x0471, 0x0101):
1053 	case USB_ID(0x0471, 0x0104):
1054 	case USB_ID(0x0471, 0x0105):
1055 	case USB_ID(0x0672, 0x1041):
1056 	/* quirk for UDA1321/N101.
1057 	 * note that detection between firmware 2.1.1.7 (N101)
1058 	 * and later 2.1.1.21 is not very clear from datasheets.
1059 	 * I hope that the min value is -15360 for newer firmware --jk
1060 	 */
1061 		if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
1062 		    cval->min == -15616) {
1063 			usb_audio_info(chip,
1064 				 "set volume quirk for UDA1321/N101 chip\n");
1065 			cval->max = -256;
1066 		}
1067 		break;
1068 
1069 	case USB_ID(0x046d, 0x09a4):
1070 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1071 			usb_audio_info(chip,
1072 				"set volume quirk for QuickCam E3500\n");
1073 			cval->min = 6080;
1074 			cval->max = 8768;
1075 			cval->res = 192;
1076 		}
1077 		break;
1078 
1079 	case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
1080 	case USB_ID(0x046d, 0x0808):
1081 	case USB_ID(0x046d, 0x0809):
1082 	case USB_ID(0x046d, 0x0819): /* Logitech Webcam C210 */
1083 	case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
1084 	case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
1085 	case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
1086 	case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
1087 	case USB_ID(0x046d, 0x08ca): /* Logitech Quickcam Fusion */
1088 	case USB_ID(0x046d, 0x0991):
1089 	case USB_ID(0x046d, 0x09a2): /* QuickCam Communicate Deluxe/S7500 */
1090 	/* Most audio usb devices lie about volume resolution.
1091 	 * Most Logitech webcams have res = 384.
1092 	 * Probably there is some logitech magic behind this number --fishor
1093 	 */
1094 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
1095 			usb_audio_info(chip,
1096 				"set resolution quirk: cval->res = 384\n");
1097 			cval->res = 384;
1098 		}
1099 		break;
1100 	}
1101 }
1102 
1103 /*
1104  * retrieve the minimum and maximum values for the specified control
1105  */
1106 static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
1107 				   int default_min, struct snd_kcontrol *kctl)
1108 {
1109 	/* for failsafe */
1110 	cval->min = default_min;
1111 	cval->max = cval->min + 1;
1112 	cval->res = 1;
1113 	cval->dBmin = cval->dBmax = 0;
1114 
1115 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1116 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1117 		cval->initialized = 1;
1118 	} else {
1119 		int minchn = 0;
1120 		if (cval->cmask) {
1121 			int i;
1122 			for (i = 0; i < MAX_CHANNELS; i++)
1123 				if (cval->cmask & (1 << i)) {
1124 					minchn = i + 1;
1125 					break;
1126 				}
1127 		}
1128 		if (get_ctl_value(cval, UAC_GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
1129 		    get_ctl_value(cval, UAC_GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
1130 			usb_audio_err(cval->head.mixer->chip,
1131 				      "%d:%d: cannot get min/max values for control %d (id %d)\n",
1132 				   cval->head.id, snd_usb_ctrl_intf(cval->head.mixer->chip),
1133 							       cval->control, cval->head.id);
1134 			return -EINVAL;
1135 		}
1136 		if (get_ctl_value(cval, UAC_GET_RES,
1137 				  (cval->control << 8) | minchn,
1138 				  &cval->res) < 0) {
1139 			cval->res = 1;
1140 		} else {
1141 			int last_valid_res = cval->res;
1142 
1143 			while (cval->res > 1) {
1144 				if (snd_usb_mixer_set_ctl_value(cval, UAC_SET_RES,
1145 								(cval->control << 8) | minchn,
1146 								cval->res / 2) < 0)
1147 					break;
1148 				cval->res /= 2;
1149 			}
1150 			if (get_ctl_value(cval, UAC_GET_RES,
1151 					  (cval->control << 8) | minchn, &cval->res) < 0)
1152 				cval->res = last_valid_res;
1153 		}
1154 		if (cval->res == 0)
1155 			cval->res = 1;
1156 
1157 		/* Additional checks for the proper resolution
1158 		 *
1159 		 * Some devices report smaller resolutions than actually
1160 		 * reacting.  They don't return errors but simply clip
1161 		 * to the lower aligned value.
1162 		 */
1163 		if (cval->min + cval->res < cval->max) {
1164 			int last_valid_res = cval->res;
1165 			int saved, test, check;
1166 			get_cur_mix_raw(cval, minchn, &saved);
1167 			for (;;) {
1168 				test = saved;
1169 				if (test < cval->max)
1170 					test += cval->res;
1171 				else
1172 					test -= cval->res;
1173 				if (test < cval->min || test > cval->max ||
1174 				    snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||
1175 				    get_cur_mix_raw(cval, minchn, &check)) {
1176 					cval->res = last_valid_res;
1177 					break;
1178 				}
1179 				if (test == check)
1180 					break;
1181 				cval->res *= 2;
1182 			}
1183 			snd_usb_set_cur_mix_value(cval, minchn, 0, saved);
1184 		}
1185 
1186 		cval->initialized = 1;
1187 	}
1188 
1189 	if (kctl)
1190 		volume_control_quirks(cval, kctl);
1191 
1192 	/* USB descriptions contain the dB scale in 1/256 dB unit
1193 	 * while ALSA TLV contains in 1/100 dB unit
1194 	 */
1195 	cval->dBmin = (convert_signed_value(cval, cval->min) * 100) / 256;
1196 	cval->dBmax = (convert_signed_value(cval, cval->max) * 100) / 256;
1197 	if (cval->dBmin > cval->dBmax) {
1198 		/* something is wrong; assume it's either from/to 0dB */
1199 		if (cval->dBmin < 0)
1200 			cval->dBmax = 0;
1201 		else if (cval->dBmin > 0)
1202 			cval->dBmin = 0;
1203 		if (cval->dBmin > cval->dBmax) {
1204 			/* totally crap, return an error */
1205 			return -EINVAL;
1206 		}
1207 	}
1208 
1209 	return 0;
1210 }
1211 
1212 #define get_min_max(cval, def)	get_min_max_with_quirks(cval, def, NULL)
1213 
1214 /* get a feature/mixer unit info */
1215 static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol,
1216 				  struct snd_ctl_elem_info *uinfo)
1217 {
1218 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1219 
1220 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1221 	    cval->val_type == USB_MIXER_INV_BOOLEAN)
1222 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1223 	else
1224 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1225 	uinfo->count = cval->channels;
1226 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1227 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1228 		uinfo->value.integer.min = 0;
1229 		uinfo->value.integer.max = 1;
1230 	} else {
1231 		if (!cval->initialized) {
1232 			get_min_max_with_quirks(cval, 0, kcontrol);
1233 			if (cval->initialized && cval->dBmin >= cval->dBmax) {
1234 				kcontrol->vd[0].access &=
1235 					~(SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1236 					  SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
1237 				snd_ctl_notify(cval->head.mixer->chip->card,
1238 					       SNDRV_CTL_EVENT_MASK_INFO,
1239 					       &kcontrol->id);
1240 			}
1241 		}
1242 		uinfo->value.integer.min = 0;
1243 		uinfo->value.integer.max =
1244 			(cval->max - cval->min + cval->res - 1) / cval->res;
1245 	}
1246 	return 0;
1247 }
1248 
1249 /* get the current value from feature/mixer unit */
1250 static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol,
1251 				 struct snd_ctl_elem_value *ucontrol)
1252 {
1253 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1254 	int c, cnt, val, err;
1255 
1256 	ucontrol->value.integer.value[0] = cval->min;
1257 	if (cval->cmask) {
1258 		cnt = 0;
1259 		for (c = 0; c < MAX_CHANNELS; c++) {
1260 			if (!(cval->cmask & (1 << c)))
1261 				continue;
1262 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &val);
1263 			if (err < 0)
1264 				return filter_error(cval, err);
1265 			val = get_relative_value(cval, val);
1266 			ucontrol->value.integer.value[cnt] = val;
1267 			cnt++;
1268 		}
1269 		return 0;
1270 	} else {
1271 		/* master channel */
1272 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1273 		if (err < 0)
1274 			return filter_error(cval, err);
1275 		val = get_relative_value(cval, val);
1276 		ucontrol->value.integer.value[0] = val;
1277 	}
1278 	return 0;
1279 }
1280 
1281 /* put the current value to feature/mixer unit */
1282 static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol,
1283 				 struct snd_ctl_elem_value *ucontrol)
1284 {
1285 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1286 	int c, cnt, val, oval, err;
1287 	int changed = 0;
1288 
1289 	if (cval->cmask) {
1290 		cnt = 0;
1291 		for (c = 0; c < MAX_CHANNELS; c++) {
1292 			if (!(cval->cmask & (1 << c)))
1293 				continue;
1294 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &oval);
1295 			if (err < 0)
1296 				return filter_error(cval, err);
1297 			val = ucontrol->value.integer.value[cnt];
1298 			val = get_abs_value(cval, val);
1299 			if (oval != val) {
1300 				snd_usb_set_cur_mix_value(cval, c + 1, cnt, val);
1301 				changed = 1;
1302 			}
1303 			cnt++;
1304 		}
1305 	} else {
1306 		/* master channel */
1307 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &oval);
1308 		if (err < 0)
1309 			return filter_error(cval, err);
1310 		val = ucontrol->value.integer.value[0];
1311 		val = get_abs_value(cval, val);
1312 		if (val != oval) {
1313 			snd_usb_set_cur_mix_value(cval, 0, 0, val);
1314 			changed = 1;
1315 		}
1316 	}
1317 	return changed;
1318 }
1319 
1320 /* get the boolean value from the master channel of a UAC control */
1321 static int mixer_ctl_master_bool_get(struct snd_kcontrol *kcontrol,
1322 				     struct snd_ctl_elem_value *ucontrol)
1323 {
1324 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1325 	int val, err;
1326 
1327 	err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1328 	if (err < 0)
1329 		return filter_error(cval, err);
1330 	val = (val != 0);
1331 	ucontrol->value.integer.value[0] = val;
1332 	return 0;
1333 }
1334 
1335 /* get the connectors status and report it as boolean type */
1336 static int mixer_ctl_connector_get(struct snd_kcontrol *kcontrol,
1337 				   struct snd_ctl_elem_value *ucontrol)
1338 {
1339 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1340 	struct snd_usb_audio *chip = cval->head.mixer->chip;
1341 	int idx = 0, validx, ret, val;
1342 
1343 	validx = cval->control << 8 | 0;
1344 
1345 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
1346 	if (ret)
1347 		goto error;
1348 
1349 	idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
1350 	if (cval->head.mixer->protocol == UAC_VERSION_2) {
1351 		struct uac2_connectors_ctl_blk uac2_conn;
1352 
1353 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1354 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1355 				      validx, idx, &uac2_conn, sizeof(uac2_conn));
1356 		val = !!uac2_conn.bNrChannels;
1357 	} else { /* UAC_VERSION_3 */
1358 		struct uac3_insertion_ctl_blk uac3_conn;
1359 
1360 		ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), UAC2_CS_CUR,
1361 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
1362 				      validx, idx, &uac3_conn, sizeof(uac3_conn));
1363 		val = !!uac3_conn.bmConInserted;
1364 	}
1365 
1366 	snd_usb_unlock_shutdown(chip);
1367 
1368 	if (ret < 0) {
1369 error:
1370 		usb_audio_err(chip,
1371 			"cannot get connectors status: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
1372 			UAC_GET_CUR, validx, idx, cval->val_type);
1373 		return ret;
1374 	}
1375 
1376 	ucontrol->value.integer.value[0] = val;
1377 	return 0;
1378 }
1379 
1380 static struct snd_kcontrol_new usb_feature_unit_ctl = {
1381 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1382 	.name = "", /* will be filled later manually */
1383 	.info = mixer_ctl_feature_info,
1384 	.get = mixer_ctl_feature_get,
1385 	.put = mixer_ctl_feature_put,
1386 };
1387 
1388 /* the read-only variant */
1389 static const struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
1390 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1391 	.name = "", /* will be filled later manually */
1392 	.info = mixer_ctl_feature_info,
1393 	.get = mixer_ctl_feature_get,
1394 	.put = NULL,
1395 };
1396 
1397 /*
1398  * A control which shows the boolean value from reading a UAC control on
1399  * the master channel.
1400  */
1401 static struct snd_kcontrol_new usb_bool_master_control_ctl_ro = {
1402 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1403 	.name = "", /* will be filled later manually */
1404 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1405 	.info = snd_ctl_boolean_mono_info,
1406 	.get = mixer_ctl_master_bool_get,
1407 	.put = NULL,
1408 };
1409 
1410 static const struct snd_kcontrol_new usb_connector_ctl_ro = {
1411 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
1412 	.name = "", /* will be filled later manually */
1413 	.access = SNDRV_CTL_ELEM_ACCESS_READ,
1414 	.info = snd_ctl_boolean_mono_info,
1415 	.get = mixer_ctl_connector_get,
1416 	.put = NULL,
1417 };
1418 
1419 /*
1420  * This symbol is exported in order to allow the mixer quirks to
1421  * hook up to the standard feature unit control mechanism
1422  */
1423 struct snd_kcontrol_new *snd_usb_feature_unit_ctl = &usb_feature_unit_ctl;
1424 
1425 /*
1426  * build a feature control
1427  */
1428 static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
1429 {
1430 	return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
1431 }
1432 
1433 /*
1434  * A lot of headsets/headphones have a "Speaker" mixer. Make sure we
1435  * rename it to "Headphone". We determine if something is a headphone
1436  * similar to how udev determines form factor.
1437  */
1438 static void check_no_speaker_on_headset(struct snd_kcontrol *kctl,
1439 					struct snd_card *card)
1440 {
1441 	const char *names_to_check[] = {
1442 		"Headset", "headset", "Headphone", "headphone", NULL};
1443 	const char **s;
1444 	bool found = false;
1445 
1446 	if (strcmp("Speaker", kctl->id.name))
1447 		return;
1448 
1449 	for (s = names_to_check; *s; s++)
1450 		if (strstr(card->shortname, *s)) {
1451 			found = true;
1452 			break;
1453 		}
1454 
1455 	if (!found)
1456 		return;
1457 
1458 	strlcpy(kctl->id.name, "Headphone", sizeof(kctl->id.name));
1459 }
1460 
1461 static struct usb_feature_control_info *get_feature_control_info(int control)
1462 {
1463 	int i;
1464 
1465 	for (i = 0; i < ARRAY_SIZE(audio_feature_info); ++i) {
1466 		if (audio_feature_info[i].control == control)
1467 			return &audio_feature_info[i];
1468 	}
1469 	return NULL;
1470 }
1471 
1472 static void __build_feature_ctl(struct usb_mixer_interface *mixer,
1473 				const struct usbmix_name_map *imap,
1474 				unsigned int ctl_mask, int control,
1475 				struct usb_audio_term *iterm,
1476 				struct usb_audio_term *oterm,
1477 				int unitid, int nameid, int readonly_mask)
1478 {
1479 	struct usb_feature_control_info *ctl_info;
1480 	unsigned int len = 0;
1481 	int mapped_name = 0;
1482 	struct snd_kcontrol *kctl;
1483 	struct usb_mixer_elem_info *cval;
1484 	const struct usbmix_name_map *map;
1485 	unsigned int range;
1486 
1487 	if (control == UAC_FU_GRAPHIC_EQUALIZER) {
1488 		/* FIXME: not supported yet */
1489 		return;
1490 	}
1491 
1492 	map = find_map(imap, unitid, control);
1493 	if (check_ignored_ctl(map))
1494 		return;
1495 
1496 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1497 	if (!cval)
1498 		return;
1499 	snd_usb_mixer_elem_init_std(&cval->head, mixer, unitid);
1500 	cval->control = control;
1501 	cval->cmask = ctl_mask;
1502 
1503 	ctl_info = get_feature_control_info(control);
1504 	if (!ctl_info) {
1505 		kfree(cval);
1506 		return;
1507 	}
1508 	if (mixer->protocol == UAC_VERSION_1)
1509 		cval->val_type = ctl_info->type;
1510 	else /* UAC_VERSION_2 */
1511 		cval->val_type = ctl_info->type_uac2 >= 0 ?
1512 			ctl_info->type_uac2 : ctl_info->type;
1513 
1514 	if (ctl_mask == 0) {
1515 		cval->channels = 1;	/* master channel */
1516 		cval->master_readonly = readonly_mask;
1517 	} else {
1518 		int i, c = 0;
1519 		for (i = 0; i < 16; i++)
1520 			if (ctl_mask & (1 << i))
1521 				c++;
1522 		cval->channels = c;
1523 		cval->ch_readonly = readonly_mask;
1524 	}
1525 
1526 	/*
1527 	 * If all channels in the mask are marked read-only, make the control
1528 	 * read-only. snd_usb_set_cur_mix_value() will check the mask again and won't
1529 	 * issue write commands to read-only channels.
1530 	 */
1531 	if (cval->channels == readonly_mask)
1532 		kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
1533 	else
1534 		kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1535 
1536 	if (!kctl) {
1537 		usb_audio_err(mixer->chip, "cannot malloc kcontrol\n");
1538 		kfree(cval);
1539 		return;
1540 	}
1541 	kctl->private_free = snd_usb_mixer_elem_free;
1542 
1543 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1544 	mapped_name = len != 0;
1545 	if (!len && nameid)
1546 		len = snd_usb_copy_string_desc(mixer->chip, nameid,
1547 				kctl->id.name, sizeof(kctl->id.name));
1548 
1549 	switch (control) {
1550 	case UAC_FU_MUTE:
1551 	case UAC_FU_VOLUME:
1552 		/*
1553 		 * determine the control name.  the rule is:
1554 		 * - if a name id is given in descriptor, use it.
1555 		 * - if the connected input can be determined, then use the name
1556 		 *   of terminal type.
1557 		 * - if the connected output can be determined, use it.
1558 		 * - otherwise, anonymous name.
1559 		 */
1560 		if (!len) {
1561 			if (iterm)
1562 				len = get_term_name(mixer->chip, iterm,
1563 						    kctl->id.name,
1564 						    sizeof(kctl->id.name), 1);
1565 			if (!len && oterm)
1566 				len = get_term_name(mixer->chip, oterm,
1567 						    kctl->id.name,
1568 						    sizeof(kctl->id.name), 1);
1569 			if (!len)
1570 				snprintf(kctl->id.name, sizeof(kctl->id.name),
1571 					 "Feature %d", unitid);
1572 		}
1573 
1574 		if (!mapped_name)
1575 			check_no_speaker_on_headset(kctl, mixer->chip->card);
1576 
1577 		/*
1578 		 * determine the stream direction:
1579 		 * if the connected output is USB stream, then it's likely a
1580 		 * capture stream.  otherwise it should be playback (hopefully :)
1581 		 */
1582 		if (!mapped_name && oterm && !(oterm->type >> 16)) {
1583 			if ((oterm->type & 0xff00) == 0x0100)
1584 				append_ctl_name(kctl, " Capture");
1585 			else
1586 				append_ctl_name(kctl, " Playback");
1587 		}
1588 		append_ctl_name(kctl, control == UAC_FU_MUTE ?
1589 				" Switch" : " Volume");
1590 		break;
1591 	default:
1592 		if (!len)
1593 			strlcpy(kctl->id.name, audio_feature_info[control-1].name,
1594 				sizeof(kctl->id.name));
1595 		break;
1596 	}
1597 
1598 	/* get min/max values */
1599 	get_min_max_with_quirks(cval, 0, kctl);
1600 
1601 	if (control == UAC_FU_VOLUME) {
1602 		check_mapped_dB(map, cval);
1603 		if (cval->dBmin < cval->dBmax || !cval->initialized) {
1604 			kctl->tlv.c = snd_usb_mixer_vol_tlv;
1605 			kctl->vd[0].access |=
1606 				SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1607 				SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1608 		}
1609 	}
1610 
1611 	snd_usb_mixer_fu_apply_quirk(mixer, cval, unitid, kctl);
1612 
1613 	range = (cval->max - cval->min) / cval->res;
1614 	/*
1615 	 * Are there devices with volume range more than 255? I use a bit more
1616 	 * to be sure. 384 is a resolution magic number found on Logitech
1617 	 * devices. It will definitively catch all buggy Logitech devices.
1618 	 */
1619 	if (range > 384) {
1620 		usb_audio_warn(mixer->chip,
1621 			       "Warning! Unlikely big volume range (=%u), cval->res is probably wrong.",
1622 			       range);
1623 		usb_audio_warn(mixer->chip,
1624 			       "[%d] FU [%s] ch = %d, val = %d/%d/%d",
1625 			       cval->head.id, kctl->id.name, cval->channels,
1626 			       cval->min, cval->max, cval->res);
1627 	}
1628 
1629 	usb_audio_dbg(mixer->chip, "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
1630 		      cval->head.id, kctl->id.name, cval->channels,
1631 		      cval->min, cval->max, cval->res);
1632 	snd_usb_mixer_add_control(&cval->head, kctl);
1633 }
1634 
1635 static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
1636 			      unsigned int ctl_mask, int control,
1637 			      struct usb_audio_term *iterm, int unitid,
1638 			      int readonly_mask)
1639 {
1640 	struct uac_feature_unit_descriptor *desc = raw_desc;
1641 	int nameid = uac_feature_unit_iFeature(desc);
1642 
1643 	__build_feature_ctl(state->mixer, state->map, ctl_mask, control,
1644 			iterm, &state->oterm, unitid, nameid, readonly_mask);
1645 }
1646 
1647 static void build_feature_ctl_badd(struct usb_mixer_interface *mixer,
1648 			      unsigned int ctl_mask, int control, int unitid,
1649 			      const struct usbmix_name_map *badd_map)
1650 {
1651 	__build_feature_ctl(mixer, badd_map, ctl_mask, control,
1652 			NULL, NULL, unitid, 0, 0);
1653 }
1654 
1655 static void get_connector_control_name(struct mixer_build *state,
1656 				       struct usb_audio_term *term,
1657 				       bool is_input, char *name, int name_size)
1658 {
1659 	int name_len = get_term_name(state->chip, term, name, name_size, 0);
1660 
1661 	if (name_len == 0)
1662 		strlcpy(name, "Unknown", name_size);
1663 
1664 	/*
1665 	 *  sound/core/ctljack.c has a convention of naming jack controls
1666 	 * by ending in " Jack".  Make it slightly more useful by
1667 	 * indicating Input or Output after the terminal name.
1668 	 */
1669 	if (is_input)
1670 		strlcat(name, " - Input Jack", name_size);
1671 	else
1672 		strlcat(name, " - Output Jack", name_size);
1673 }
1674 
1675 /* Build a mixer control for a UAC connector control (jack-detect) */
1676 static void build_connector_control(struct mixer_build *state,
1677 				    struct usb_audio_term *term, bool is_input)
1678 {
1679 	struct snd_kcontrol *kctl;
1680 	struct usb_mixer_elem_info *cval;
1681 
1682 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1683 	if (!cval)
1684 		return;
1685 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, term->id);
1686 	/*
1687 	 * UAC2: The first byte from reading the UAC2_TE_CONNECTOR control returns the
1688 	 * number of channels connected.
1689 	 *
1690 	 * UAC3: The first byte specifies size of bitmap for the inserted controls. The
1691 	 * following byte(s) specifies which connectors are inserted.
1692 	 *
1693 	 * This boolean ctl will simply report if any channels are connected
1694 	 * or not.
1695 	 */
1696 	if (state->mixer->protocol == UAC_VERSION_2)
1697 		cval->control = UAC2_TE_CONNECTOR;
1698 	else /* UAC_VERSION_3 */
1699 		cval->control = UAC3_TE_INSERTION;
1700 
1701 	cval->val_type = USB_MIXER_BOOLEAN;
1702 	cval->channels = 1; /* report true if any channel is connected */
1703 	cval->min = 0;
1704 	cval->max = 1;
1705 	kctl = snd_ctl_new1(&usb_connector_ctl_ro, cval);
1706 	if (!kctl) {
1707 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
1708 		kfree(cval);
1709 		return;
1710 	}
1711 	get_connector_control_name(state, term, is_input, kctl->id.name,
1712 				   sizeof(kctl->id.name));
1713 	kctl->private_free = snd_usb_mixer_elem_free;
1714 	snd_usb_mixer_add_control(&cval->head, kctl);
1715 }
1716 
1717 static int parse_clock_source_unit(struct mixer_build *state, int unitid,
1718 				   void *_ftr)
1719 {
1720 	struct uac_clock_source_descriptor *hdr = _ftr;
1721 	struct usb_mixer_elem_info *cval;
1722 	struct snd_kcontrol *kctl;
1723 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
1724 	int ret;
1725 
1726 	if (state->mixer->protocol != UAC_VERSION_2)
1727 		return -EINVAL;
1728 
1729 	if (hdr->bLength != sizeof(*hdr)) {
1730 		usb_audio_dbg(state->chip,
1731 			      "Bogus clock source descriptor length of %d, ignoring.\n",
1732 			      hdr->bLength);
1733 		return 0;
1734 	}
1735 
1736 	/*
1737 	 * The only property of this unit we are interested in is the
1738 	 * clock source validity. If that isn't readable, just bail out.
1739 	 */
1740 	if (!uac_v2v3_control_is_readable(hdr->bmControls,
1741 				      UAC2_CS_CONTROL_CLOCK_VALID))
1742 		return 0;
1743 
1744 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1745 	if (!cval)
1746 		return -ENOMEM;
1747 
1748 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, hdr->bClockID);
1749 
1750 	cval->min = 0;
1751 	cval->max = 1;
1752 	cval->channels = 1;
1753 	cval->val_type = USB_MIXER_BOOLEAN;
1754 	cval->control = UAC2_CS_CONTROL_CLOCK_VALID;
1755 
1756 	cval->master_readonly = 1;
1757 	/* From UAC2 5.2.5.1.2 "Only the get request is supported." */
1758 	kctl = snd_ctl_new1(&usb_bool_master_control_ctl_ro, cval);
1759 
1760 	if (!kctl) {
1761 		kfree(cval);
1762 		return -ENOMEM;
1763 	}
1764 
1765 	kctl->private_free = snd_usb_mixer_elem_free;
1766 	ret = snd_usb_copy_string_desc(state->chip, hdr->iClockSource,
1767 				       name, sizeof(name));
1768 	if (ret > 0)
1769 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1770 			 "%s Validity", name);
1771 	else
1772 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1773 			 "Clock Source %d Validity", hdr->bClockID);
1774 
1775 	return snd_usb_mixer_add_control(&cval->head, kctl);
1776 }
1777 
1778 /*
1779  * parse a feature unit
1780  *
1781  * most of controls are defined here.
1782  */
1783 static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
1784 				    void *_ftr)
1785 {
1786 	int channels, i, j;
1787 	struct usb_audio_term iterm;
1788 	unsigned int master_bits, first_ch_bits;
1789 	int err, csize;
1790 	struct uac_feature_unit_descriptor *hdr = _ftr;
1791 	__u8 *bmaControls;
1792 
1793 	if (state->mixer->protocol == UAC_VERSION_1) {
1794 		if (hdr->bLength < 7) {
1795 			usb_audio_err(state->chip,
1796 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1797 				      unitid);
1798 			return -EINVAL;
1799 		}
1800 		csize = hdr->bControlSize;
1801 		if (!csize) {
1802 			usb_audio_dbg(state->chip,
1803 				      "unit %u: invalid bControlSize == 0\n",
1804 				      unitid);
1805 			return -EINVAL;
1806 		}
1807 		channels = (hdr->bLength - 7) / csize - 1;
1808 		bmaControls = hdr->bmaControls;
1809 		if (hdr->bLength < 7 + csize) {
1810 			usb_audio_err(state->chip,
1811 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1812 				      unitid);
1813 			return -EINVAL;
1814 		}
1815 	} else if (state->mixer->protocol == UAC_VERSION_2) {
1816 		struct uac2_feature_unit_descriptor *ftr = _ftr;
1817 		if (hdr->bLength < 6) {
1818 			usb_audio_err(state->chip,
1819 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1820 				      unitid);
1821 			return -EINVAL;
1822 		}
1823 		csize = 4;
1824 		channels = (hdr->bLength - 6) / 4 - 1;
1825 		bmaControls = ftr->bmaControls;
1826 		if (hdr->bLength < 6 + csize) {
1827 			usb_audio_err(state->chip,
1828 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1829 				      unitid);
1830 			return -EINVAL;
1831 		}
1832 	} else { /* UAC_VERSION_3 */
1833 		struct uac3_feature_unit_descriptor *ftr = _ftr;
1834 
1835 		if (hdr->bLength < 7) {
1836 			usb_audio_err(state->chip,
1837 				      "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n",
1838 				      unitid);
1839 			return -EINVAL;
1840 		}
1841 		csize = 4;
1842 		channels = (ftr->bLength - 7) / 4 - 1;
1843 		bmaControls = ftr->bmaControls;
1844 		if (hdr->bLength < 7 + csize) {
1845 			usb_audio_err(state->chip,
1846 				      "unit %u: invalid UAC3_FEATURE_UNIT descriptor\n",
1847 				      unitid);
1848 			return -EINVAL;
1849 		}
1850 	}
1851 
1852 	/* parse the source unit */
1853 	if ((err = parse_audio_unit(state, hdr->bSourceID)) < 0)
1854 		return err;
1855 
1856 	/* determine the input source type and name */
1857 	err = check_input_term(state, hdr->bSourceID, &iterm);
1858 	if (err < 0)
1859 		return err;
1860 
1861 	master_bits = snd_usb_combine_bytes(bmaControls, csize);
1862 	/* master configuration quirks */
1863 	switch (state->chip->usb_id) {
1864 	case USB_ID(0x08bb, 0x2702):
1865 		usb_audio_info(state->chip,
1866 			       "usbmixer: master volume quirk for PCM2702 chip\n");
1867 		/* disable non-functional volume control */
1868 		master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
1869 		break;
1870 	case USB_ID(0x1130, 0xf211):
1871 		usb_audio_info(state->chip,
1872 			       "usbmixer: volume control quirk for Tenx TP6911 Audio Headset\n");
1873 		/* disable non-functional volume control */
1874 		channels = 0;
1875 		break;
1876 
1877 	}
1878 	if (channels > 0)
1879 		first_ch_bits = snd_usb_combine_bytes(bmaControls + csize, csize);
1880 	else
1881 		first_ch_bits = 0;
1882 
1883 	if (state->mixer->protocol == UAC_VERSION_1) {
1884 		/* check all control types */
1885 		for (i = 0; i < 10; i++) {
1886 			unsigned int ch_bits = 0;
1887 			int control = audio_feature_info[i].control;
1888 
1889 			for (j = 0; j < channels; j++) {
1890 				unsigned int mask;
1891 
1892 				mask = snd_usb_combine_bytes(bmaControls +
1893 							     csize * (j+1), csize);
1894 				if (mask & (1 << i))
1895 					ch_bits |= (1 << j);
1896 			}
1897 			/* audio class v1 controls are never read-only */
1898 
1899 			/*
1900 			 * The first channel must be set
1901 			 * (for ease of programming).
1902 			 */
1903 			if (ch_bits & 1)
1904 				build_feature_ctl(state, _ftr, ch_bits, control,
1905 						  &iterm, unitid, 0);
1906 			if (master_bits & (1 << i))
1907 				build_feature_ctl(state, _ftr, 0, control,
1908 						  &iterm, unitid, 0);
1909 		}
1910 	} else { /* UAC_VERSION_2/3 */
1911 		for (i = 0; i < ARRAY_SIZE(audio_feature_info); i++) {
1912 			unsigned int ch_bits = 0;
1913 			unsigned int ch_read_only = 0;
1914 			int control = audio_feature_info[i].control;
1915 
1916 			for (j = 0; j < channels; j++) {
1917 				unsigned int mask;
1918 
1919 				mask = snd_usb_combine_bytes(bmaControls +
1920 							     csize * (j+1), csize);
1921 				if (uac_v2v3_control_is_readable(mask, control)) {
1922 					ch_bits |= (1 << j);
1923 					if (!uac_v2v3_control_is_writeable(mask, control))
1924 						ch_read_only |= (1 << j);
1925 				}
1926 			}
1927 
1928 			/*
1929 			 * NOTE: build_feature_ctl() will mark the control
1930 			 * read-only if all channels are marked read-only in
1931 			 * the descriptors. Otherwise, the control will be
1932 			 * reported as writeable, but the driver will not
1933 			 * actually issue a write command for read-only
1934 			 * channels.
1935 			 */
1936 
1937 			/*
1938 			 * The first channel must be set
1939 			 * (for ease of programming).
1940 			 */
1941 			if (ch_bits & 1)
1942 				build_feature_ctl(state, _ftr, ch_bits, control,
1943 						  &iterm, unitid, ch_read_only);
1944 			if (uac_v2v3_control_is_readable(master_bits, control))
1945 				build_feature_ctl(state, _ftr, 0, control,
1946 						  &iterm, unitid,
1947 						  !uac_v2v3_control_is_writeable(master_bits,
1948 										 control));
1949 		}
1950 	}
1951 
1952 	return 0;
1953 }
1954 
1955 /*
1956  * Mixer Unit
1957  */
1958 
1959 /*
1960  * build a mixer unit control
1961  *
1962  * the callbacks are identical with feature unit.
1963  * input channel number (zero based) is given in control field instead.
1964  */
1965 static void build_mixer_unit_ctl(struct mixer_build *state,
1966 				 struct uac_mixer_unit_descriptor *desc,
1967 				 int in_pin, int in_ch, int num_outs,
1968 				 int unitid, struct usb_audio_term *iterm)
1969 {
1970 	struct usb_mixer_elem_info *cval;
1971 	unsigned int i, len;
1972 	struct snd_kcontrol *kctl;
1973 	const struct usbmix_name_map *map;
1974 
1975 	map = find_map(state->map, unitid, 0);
1976 	if (check_ignored_ctl(map))
1977 		return;
1978 
1979 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1980 	if (!cval)
1981 		return;
1982 
1983 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
1984 	cval->control = in_ch + 1; /* based on 1 */
1985 	cval->val_type = USB_MIXER_S16;
1986 	for (i = 0; i < num_outs; i++) {
1987 		__u8 *c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
1988 
1989 		if (check_matrix_bitmap(c, in_ch, i, num_outs)) {
1990 			cval->cmask |= (1 << i);
1991 			cval->channels++;
1992 		}
1993 	}
1994 
1995 	/* get min/max values */
1996 	get_min_max(cval, 0);
1997 
1998 	kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1999 	if (!kctl) {
2000 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2001 		kfree(cval);
2002 		return;
2003 	}
2004 	kctl->private_free = snd_usb_mixer_elem_free;
2005 
2006 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2007 	if (!len)
2008 		len = get_term_name(state->chip, iterm, kctl->id.name,
2009 				    sizeof(kctl->id.name), 0);
2010 	if (!len)
2011 		len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
2012 	append_ctl_name(kctl, " Volume");
2013 
2014 	usb_audio_dbg(state->chip, "[%d] MU [%s] ch = %d, val = %d/%d\n",
2015 		    cval->head.id, kctl->id.name, cval->channels, cval->min, cval->max);
2016 	snd_usb_mixer_add_control(&cval->head, kctl);
2017 }
2018 
2019 static int parse_audio_input_terminal(struct mixer_build *state, int unitid,
2020 				      void *raw_desc)
2021 {
2022 	struct usb_audio_term iterm;
2023 	unsigned int control, bmctls, term_id;
2024 
2025 	if (state->mixer->protocol == UAC_VERSION_2) {
2026 		struct uac2_input_terminal_descriptor *d_v2 = raw_desc;
2027 		control = UAC2_TE_CONNECTOR;
2028 		term_id = d_v2->bTerminalID;
2029 		bmctls = le16_to_cpu(d_v2->bmControls);
2030 	} else if (state->mixer->protocol == UAC_VERSION_3) {
2031 		struct uac3_input_terminal_descriptor *d_v3 = raw_desc;
2032 		control = UAC3_TE_INSERTION;
2033 		term_id = d_v3->bTerminalID;
2034 		bmctls = le32_to_cpu(d_v3->bmControls);
2035 	} else {
2036 		return 0; /* UAC1. No Insertion control */
2037 	}
2038 
2039 	check_input_term(state, term_id, &iterm);
2040 
2041 	/* Check for jack detection. */
2042 	if (uac_v2v3_control_is_readable(bmctls, control))
2043 		build_connector_control(state, &iterm, true);
2044 
2045 	return 0;
2046 }
2047 
2048 /*
2049  * parse a mixer unit
2050  */
2051 static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
2052 				  void *raw_desc)
2053 {
2054 	struct uac_mixer_unit_descriptor *desc = raw_desc;
2055 	struct usb_audio_term iterm;
2056 	int input_pins, num_ins, num_outs;
2057 	int pin, ich, err;
2058 
2059 	err = uac_mixer_unit_get_channels(state, desc);
2060 	if (err < 0) {
2061 		usb_audio_err(state->chip,
2062 			      "invalid MIXER UNIT descriptor %d\n",
2063 			      unitid);
2064 		return err;
2065 	}
2066 
2067 	num_outs = err;
2068 	input_pins = desc->bNrInPins;
2069 
2070 	num_ins = 0;
2071 	ich = 0;
2072 	for (pin = 0; pin < input_pins; pin++) {
2073 		err = parse_audio_unit(state, desc->baSourceID[pin]);
2074 		if (err < 0)
2075 			continue;
2076 		/* no bmControls field (e.g. Maya44) -> ignore */
2077 		if (desc->bLength <= 10 + input_pins)
2078 			continue;
2079 		err = check_input_term(state, desc->baSourceID[pin], &iterm);
2080 		if (err < 0)
2081 			return err;
2082 		num_ins += iterm.channels;
2083 		for (; ich < num_ins; ich++) {
2084 			int och, ich_has_controls = 0;
2085 
2086 			for (och = 0; och < num_outs; och++) {
2087 				__u8 *c = uac_mixer_unit_bmControls(desc,
2088 						state->mixer->protocol);
2089 
2090 				if (check_matrix_bitmap(c, ich, och, num_outs)) {
2091 					ich_has_controls = 1;
2092 					break;
2093 				}
2094 			}
2095 			if (ich_has_controls)
2096 				build_mixer_unit_ctl(state, desc, pin, ich, num_outs,
2097 						     unitid, &iterm);
2098 		}
2099 	}
2100 	return 0;
2101 }
2102 
2103 /*
2104  * Processing Unit / Extension Unit
2105  */
2106 
2107 /* get callback for processing/extension unit */
2108 static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol,
2109 				  struct snd_ctl_elem_value *ucontrol)
2110 {
2111 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2112 	int err, val;
2113 
2114 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2115 	if (err < 0) {
2116 		ucontrol->value.integer.value[0] = cval->min;
2117 		return filter_error(cval, err);
2118 	}
2119 	val = get_relative_value(cval, val);
2120 	ucontrol->value.integer.value[0] = val;
2121 	return 0;
2122 }
2123 
2124 /* put callback for processing/extension unit */
2125 static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol,
2126 				  struct snd_ctl_elem_value *ucontrol)
2127 {
2128 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2129 	int val, oval, err;
2130 
2131 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2132 	if (err < 0)
2133 		return filter_error(cval, err);
2134 	val = ucontrol->value.integer.value[0];
2135 	val = get_abs_value(cval, val);
2136 	if (val != oval) {
2137 		set_cur_ctl_value(cval, cval->control << 8, val);
2138 		return 1;
2139 	}
2140 	return 0;
2141 }
2142 
2143 /* alsa control interface for processing/extension unit */
2144 static const struct snd_kcontrol_new mixer_procunit_ctl = {
2145 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2146 	.name = "", /* will be filled later */
2147 	.info = mixer_ctl_feature_info,
2148 	.get = mixer_ctl_procunit_get,
2149 	.put = mixer_ctl_procunit_put,
2150 };
2151 
2152 /*
2153  * predefined data for processing units
2154  */
2155 struct procunit_value_info {
2156 	int control;
2157 	char *suffix;
2158 	int val_type;
2159 	int min_value;
2160 };
2161 
2162 struct procunit_info {
2163 	int type;
2164 	char *name;
2165 	struct procunit_value_info *values;
2166 };
2167 
2168 static struct procunit_value_info updown_proc_info[] = {
2169 	{ UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2170 	{ UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2171 	{ 0 }
2172 };
2173 static struct procunit_value_info prologic_proc_info[] = {
2174 	{ UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2175 	{ UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
2176 	{ 0 }
2177 };
2178 static struct procunit_value_info threed_enh_proc_info[] = {
2179 	{ UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2180 	{ UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
2181 	{ 0 }
2182 };
2183 static struct procunit_value_info reverb_proc_info[] = {
2184 	{ UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2185 	{ UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
2186 	{ UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
2187 	{ UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
2188 	{ 0 }
2189 };
2190 static struct procunit_value_info chorus_proc_info[] = {
2191 	{ UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2192 	{ UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
2193 	{ UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
2194 	{ UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
2195 	{ 0 }
2196 };
2197 static struct procunit_value_info dcr_proc_info[] = {
2198 	{ UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
2199 	{ UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
2200 	{ UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
2201 	{ UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
2202 	{ UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
2203 	{ UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
2204 	{ 0 }
2205 };
2206 
2207 static struct procunit_info procunits[] = {
2208 	{ UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
2209 	{ UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
2210 	{ UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
2211 	{ UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
2212 	{ UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
2213 	{ UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
2214 	{ 0 },
2215 };
2216 /*
2217  * predefined data for extension units
2218  */
2219 static struct procunit_value_info clock_rate_xu_info[] = {
2220 	{ USB_XU_CLOCK_RATE_SELECTOR, "Selector", USB_MIXER_U8, 0 },
2221 	{ 0 }
2222 };
2223 static struct procunit_value_info clock_source_xu_info[] = {
2224 	{ USB_XU_CLOCK_SOURCE_SELECTOR, "External", USB_MIXER_BOOLEAN },
2225 	{ 0 }
2226 };
2227 static struct procunit_value_info spdif_format_xu_info[] = {
2228 	{ USB_XU_DIGITAL_FORMAT_SELECTOR, "SPDIF/AC3", USB_MIXER_BOOLEAN },
2229 	{ 0 }
2230 };
2231 static struct procunit_value_info soft_limit_xu_info[] = {
2232 	{ USB_XU_SOFT_LIMIT_SELECTOR, " ", USB_MIXER_BOOLEAN },
2233 	{ 0 }
2234 };
2235 static struct procunit_info extunits[] = {
2236 	{ USB_XU_CLOCK_RATE, "Clock rate", clock_rate_xu_info },
2237 	{ USB_XU_CLOCK_SOURCE, "DigitalIn CLK source", clock_source_xu_info },
2238 	{ USB_XU_DIGITAL_IO_STATUS, "DigitalOut format:", spdif_format_xu_info },
2239 	{ USB_XU_DEVICE_OPTIONS, "AnalogueIn Soft Limit", soft_limit_xu_info },
2240 	{ 0 }
2241 };
2242 
2243 /*
2244  * build a processing/extension unit
2245  */
2246 static int build_audio_procunit(struct mixer_build *state, int unitid,
2247 				void *raw_desc, struct procunit_info *list,
2248 				char *name)
2249 {
2250 	struct uac_processing_unit_descriptor *desc = raw_desc;
2251 	int num_ins = desc->bNrInPins;
2252 	struct usb_mixer_elem_info *cval;
2253 	struct snd_kcontrol *kctl;
2254 	int i, err, nameid, type, len;
2255 	struct procunit_info *info;
2256 	struct procunit_value_info *valinfo;
2257 	const struct usbmix_name_map *map;
2258 	static struct procunit_value_info default_value_info[] = {
2259 		{ 0x01, "Switch", USB_MIXER_BOOLEAN },
2260 		{ 0 }
2261 	};
2262 	static struct procunit_info default_info = {
2263 		0, NULL, default_value_info
2264 	};
2265 
2266 	if (desc->bLength < 13 || desc->bLength < 13 + num_ins ||
2267 	    desc->bLength < num_ins + uac_processing_unit_bControlSize(desc, state->mixer->protocol)) {
2268 		usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid);
2269 		return -EINVAL;
2270 	}
2271 
2272 	for (i = 0; i < num_ins; i++) {
2273 		if ((err = parse_audio_unit(state, desc->baSourceID[i])) < 0)
2274 			return err;
2275 	}
2276 
2277 	type = le16_to_cpu(desc->wProcessType);
2278 	for (info = list; info && info->type; info++)
2279 		if (info->type == type)
2280 			break;
2281 	if (!info || !info->type)
2282 		info = &default_info;
2283 
2284 	for (valinfo = info->values; valinfo->control; valinfo++) {
2285 		__u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);
2286 
2287 		if (!(controls[valinfo->control / 8] & (1 << ((valinfo->control % 8) - 1))))
2288 			continue;
2289 		map = find_map(state->map, unitid, valinfo->control);
2290 		if (check_ignored_ctl(map))
2291 			continue;
2292 		cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2293 		if (!cval)
2294 			return -ENOMEM;
2295 		snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2296 		cval->control = valinfo->control;
2297 		cval->val_type = valinfo->val_type;
2298 		cval->channels = 1;
2299 
2300 		/* get min/max values */
2301 		if (type == UAC_PROCESS_UP_DOWNMIX && cval->control == UAC_UD_MODE_SELECT) {
2302 			__u8 *control_spec = uac_processing_unit_specific(desc, state->mixer->protocol);
2303 			/* FIXME: hard-coded */
2304 			cval->min = 1;
2305 			cval->max = control_spec[0];
2306 			cval->res = 1;
2307 			cval->initialized = 1;
2308 		} else {
2309 			if (type == USB_XU_CLOCK_RATE) {
2310 				/*
2311 				 * E-Mu USB 0404/0202/TrackerPre/0204
2312 				 * samplerate control quirk
2313 				 */
2314 				cval->min = 0;
2315 				cval->max = 5;
2316 				cval->res = 1;
2317 				cval->initialized = 1;
2318 			} else
2319 				get_min_max(cval, valinfo->min_value);
2320 		}
2321 
2322 		kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
2323 		if (!kctl) {
2324 			kfree(cval);
2325 			return -ENOMEM;
2326 		}
2327 		kctl->private_free = snd_usb_mixer_elem_free;
2328 
2329 		if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name))) {
2330 			/* nothing */ ;
2331 		} else if (info->name) {
2332 			strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
2333 		} else {
2334 			nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
2335 			len = 0;
2336 			if (nameid)
2337 				len = snd_usb_copy_string_desc(state->chip,
2338 							       nameid,
2339 							       kctl->id.name,
2340 							       sizeof(kctl->id.name));
2341 			if (!len)
2342 				strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
2343 		}
2344 		append_ctl_name(kctl, " ");
2345 		append_ctl_name(kctl, valinfo->suffix);
2346 
2347 		usb_audio_dbg(state->chip,
2348 			      "[%d] PU [%s] ch = %d, val = %d/%d\n",
2349 			      cval->head.id, kctl->id.name, cval->channels,
2350 			      cval->min, cval->max);
2351 
2352 		err = snd_usb_mixer_add_control(&cval->head, kctl);
2353 		if (err < 0)
2354 			return err;
2355 	}
2356 	return 0;
2357 }
2358 
2359 static int parse_audio_processing_unit(struct mixer_build *state, int unitid,
2360 				       void *raw_desc)
2361 {
2362 	return build_audio_procunit(state, unitid, raw_desc,
2363 				    procunits, "Processing Unit");
2364 }
2365 
2366 static int parse_audio_extension_unit(struct mixer_build *state, int unitid,
2367 				      void *raw_desc)
2368 {
2369 	/*
2370 	 * Note that we parse extension units with processing unit descriptors.
2371 	 * That's ok as the layout is the same.
2372 	 */
2373 	return build_audio_procunit(state, unitid, raw_desc,
2374 				    extunits, "Extension Unit");
2375 }
2376 
2377 /*
2378  * Selector Unit
2379  */
2380 
2381 /*
2382  * info callback for selector unit
2383  * use an enumerator type for routing
2384  */
2385 static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol,
2386 				   struct snd_ctl_elem_info *uinfo)
2387 {
2388 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2389 	const char **itemlist = (const char **)kcontrol->private_value;
2390 
2391 	if (snd_BUG_ON(!itemlist))
2392 		return -EINVAL;
2393 	return snd_ctl_enum_info(uinfo, 1, cval->max, itemlist);
2394 }
2395 
2396 /* get callback for selector unit */
2397 static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol,
2398 				  struct snd_ctl_elem_value *ucontrol)
2399 {
2400 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2401 	int val, err;
2402 
2403 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2404 	if (err < 0) {
2405 		ucontrol->value.enumerated.item[0] = 0;
2406 		return filter_error(cval, err);
2407 	}
2408 	val = get_relative_value(cval, val);
2409 	ucontrol->value.enumerated.item[0] = val;
2410 	return 0;
2411 }
2412 
2413 /* put callback for selector unit */
2414 static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol,
2415 				  struct snd_ctl_elem_value *ucontrol)
2416 {
2417 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2418 	int val, oval, err;
2419 
2420 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2421 	if (err < 0)
2422 		return filter_error(cval, err);
2423 	val = ucontrol->value.enumerated.item[0];
2424 	val = get_abs_value(cval, val);
2425 	if (val != oval) {
2426 		set_cur_ctl_value(cval, cval->control << 8, val);
2427 		return 1;
2428 	}
2429 	return 0;
2430 }
2431 
2432 /* alsa control interface for selector unit */
2433 static const struct snd_kcontrol_new mixer_selectunit_ctl = {
2434 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2435 	.name = "", /* will be filled later */
2436 	.info = mixer_ctl_selector_info,
2437 	.get = mixer_ctl_selector_get,
2438 	.put = mixer_ctl_selector_put,
2439 };
2440 
2441 /*
2442  * private free callback.
2443  * free both private_data and private_value
2444  */
2445 static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
2446 {
2447 	int i, num_ins = 0;
2448 
2449 	if (kctl->private_data) {
2450 		struct usb_mixer_elem_info *cval = kctl->private_data;
2451 		num_ins = cval->max;
2452 		kfree(cval);
2453 		kctl->private_data = NULL;
2454 	}
2455 	if (kctl->private_value) {
2456 		char **itemlist = (char **)kctl->private_value;
2457 		for (i = 0; i < num_ins; i++)
2458 			kfree(itemlist[i]);
2459 		kfree(itemlist);
2460 		kctl->private_value = 0;
2461 	}
2462 }
2463 
2464 /*
2465  * parse a selector unit
2466  */
2467 static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
2468 				     void *raw_desc)
2469 {
2470 	struct uac_selector_unit_descriptor *desc = raw_desc;
2471 	unsigned int i, nameid, len;
2472 	int err;
2473 	struct usb_mixer_elem_info *cval;
2474 	struct snd_kcontrol *kctl;
2475 	const struct usbmix_name_map *map;
2476 	char **namelist;
2477 
2478 	if (desc->bLength < 5 || !desc->bNrInPins ||
2479 	    desc->bLength < 5 + desc->bNrInPins) {
2480 		usb_audio_err(state->chip,
2481 			"invalid SELECTOR UNIT descriptor %d\n", unitid);
2482 		return -EINVAL;
2483 	}
2484 
2485 	for (i = 0; i < desc->bNrInPins; i++) {
2486 		if ((err = parse_audio_unit(state, desc->baSourceID[i])) < 0)
2487 			return err;
2488 	}
2489 
2490 	if (desc->bNrInPins == 1) /* only one ? nonsense! */
2491 		return 0;
2492 
2493 	map = find_map(state->map, unitid, 0);
2494 	if (check_ignored_ctl(map))
2495 		return 0;
2496 
2497 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2498 	if (!cval)
2499 		return -ENOMEM;
2500 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2501 	cval->val_type = USB_MIXER_U8;
2502 	cval->channels = 1;
2503 	cval->min = 1;
2504 	cval->max = desc->bNrInPins;
2505 	cval->res = 1;
2506 	cval->initialized = 1;
2507 
2508 	if (state->mixer->protocol == UAC_VERSION_1)
2509 		cval->control = 0;
2510 	else /* UAC_VERSION_2 */
2511 		cval->control = (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR) ?
2512 			UAC2_CX_CLOCK_SELECTOR : UAC2_SU_SELECTOR;
2513 
2514 	namelist = kmalloc(sizeof(char *) * desc->bNrInPins, GFP_KERNEL);
2515 	if (!namelist) {
2516 		kfree(cval);
2517 		return -ENOMEM;
2518 	}
2519 #define MAX_ITEM_NAME_LEN	64
2520 	for (i = 0; i < desc->bNrInPins; i++) {
2521 		struct usb_audio_term iterm;
2522 		len = 0;
2523 		namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
2524 		if (!namelist[i]) {
2525 			while (i--)
2526 				kfree(namelist[i]);
2527 			kfree(namelist);
2528 			kfree(cval);
2529 			return -ENOMEM;
2530 		}
2531 		len = check_mapped_selector_name(state, unitid, i, namelist[i],
2532 						 MAX_ITEM_NAME_LEN);
2533 		if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
2534 			len = get_term_name(state->chip, &iterm, namelist[i],
2535 					    MAX_ITEM_NAME_LEN, 0);
2536 		if (! len)
2537 			sprintf(namelist[i], "Input %u", i);
2538 	}
2539 
2540 	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
2541 	if (! kctl) {
2542 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2543 		kfree(namelist);
2544 		kfree(cval);
2545 		return -ENOMEM;
2546 	}
2547 	kctl->private_value = (unsigned long)namelist;
2548 	kctl->private_free = usb_mixer_selector_elem_free;
2549 
2550 	/* check the static mapping table at first */
2551 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2552 	if (!len) {
2553 		/* no mapping ? */
2554 		/* if iSelector is given, use it */
2555 		nameid = uac_selector_unit_iSelector(desc);
2556 		if (nameid)
2557 			len = snd_usb_copy_string_desc(state->chip, nameid,
2558 						       kctl->id.name,
2559 						       sizeof(kctl->id.name));
2560 		/* ... or pick up the terminal name at next */
2561 		if (!len)
2562 			len = get_term_name(state->chip, &state->oterm,
2563 				    kctl->id.name, sizeof(kctl->id.name), 0);
2564 		/* ... or use the fixed string "USB" as the last resort */
2565 		if (!len)
2566 			strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
2567 
2568 		/* and add the proper suffix */
2569 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR)
2570 			append_ctl_name(kctl, " Clock Source");
2571 		else if ((state->oterm.type & 0xff00) == 0x0100)
2572 			append_ctl_name(kctl, " Capture Source");
2573 		else
2574 			append_ctl_name(kctl, " Playback Source");
2575 	}
2576 
2577 	usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
2578 		    cval->head.id, kctl->id.name, desc->bNrInPins);
2579 	return snd_usb_mixer_add_control(&cval->head, kctl);
2580 }
2581 
2582 /*
2583  * parse an audio unit recursively
2584  */
2585 
2586 static int parse_audio_unit(struct mixer_build *state, int unitid)
2587 {
2588 	unsigned char *p1;
2589 	int protocol = state->mixer->protocol;
2590 
2591 	if (test_and_set_bit(unitid, state->unitbitmap))
2592 		return 0; /* the unit already visited */
2593 
2594 	p1 = find_audio_control_unit(state, unitid);
2595 	if (!p1) {
2596 		usb_audio_err(state->chip, "unit %d not found!\n", unitid);
2597 		return -EINVAL;
2598 	}
2599 
2600 	if (protocol == UAC_VERSION_1 || protocol == UAC_VERSION_2) {
2601 		switch (p1[2]) {
2602 		case UAC_INPUT_TERMINAL:
2603 			return parse_audio_input_terminal(state, unitid, p1);
2604 		case UAC_MIXER_UNIT:
2605 			return parse_audio_mixer_unit(state, unitid, p1);
2606 		case UAC2_CLOCK_SOURCE:
2607 			return parse_clock_source_unit(state, unitid, p1);
2608 		case UAC_SELECTOR_UNIT:
2609 		case UAC2_CLOCK_SELECTOR:
2610 			return parse_audio_selector_unit(state, unitid, p1);
2611 		case UAC_FEATURE_UNIT:
2612 			return parse_audio_feature_unit(state, unitid, p1);
2613 		case UAC1_PROCESSING_UNIT:
2614 		/*   UAC2_EFFECT_UNIT has the same value */
2615 			if (protocol == UAC_VERSION_1)
2616 				return parse_audio_processing_unit(state, unitid, p1);
2617 			else
2618 				return 0; /* FIXME - effect units not implemented yet */
2619 		case UAC1_EXTENSION_UNIT:
2620 		/*   UAC2_PROCESSING_UNIT_V2 has the same value */
2621 			if (protocol == UAC_VERSION_1)
2622 				return parse_audio_extension_unit(state, unitid, p1);
2623 			else /* UAC_VERSION_2 */
2624 				return parse_audio_processing_unit(state, unitid, p1);
2625 		case UAC2_EXTENSION_UNIT_V2:
2626 			return parse_audio_extension_unit(state, unitid, p1);
2627 		default:
2628 			usb_audio_err(state->chip,
2629 				"unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
2630 			return -EINVAL;
2631 		}
2632 	} else { /* UAC_VERSION_3 */
2633 		switch (p1[2]) {
2634 		case UAC_INPUT_TERMINAL:
2635 			return parse_audio_input_terminal(state, unitid, p1);
2636 		case UAC3_MIXER_UNIT:
2637 			return parse_audio_mixer_unit(state, unitid, p1);
2638 		case UAC3_CLOCK_SOURCE:
2639 			return parse_clock_source_unit(state, unitid, p1);
2640 		case UAC3_CLOCK_SELECTOR:
2641 			return parse_audio_selector_unit(state, unitid, p1);
2642 		case UAC3_FEATURE_UNIT:
2643 			return parse_audio_feature_unit(state, unitid, p1);
2644 		case UAC3_EFFECT_UNIT:
2645 			return 0; /* FIXME - effect units not implemented yet */
2646 		case UAC3_PROCESSING_UNIT:
2647 			return parse_audio_processing_unit(state, unitid, p1);
2648 		case UAC3_EXTENSION_UNIT:
2649 			return parse_audio_extension_unit(state, unitid, p1);
2650 		default:
2651 			usb_audio_err(state->chip,
2652 				"unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
2653 			return -EINVAL;
2654 		}
2655 	}
2656 }
2657 
2658 static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
2659 {
2660 	/* kill pending URBs */
2661 	snd_usb_mixer_disconnect(mixer);
2662 
2663 	kfree(mixer->id_elems);
2664 	if (mixer->urb) {
2665 		kfree(mixer->urb->transfer_buffer);
2666 		usb_free_urb(mixer->urb);
2667 	}
2668 	usb_free_urb(mixer->rc_urb);
2669 	kfree(mixer->rc_setup_packet);
2670 	kfree(mixer);
2671 }
2672 
2673 static int snd_usb_mixer_dev_free(struct snd_device *device)
2674 {
2675 	struct usb_mixer_interface *mixer = device->device_data;
2676 	snd_usb_mixer_free(mixer);
2677 	return 0;
2678 }
2679 
2680 /* UAC3 predefined channels configuration */
2681 struct uac3_badd_profile {
2682 	int subclass;
2683 	const char *name;
2684 	int c_chmask;	/* capture channels mask */
2685 	int p_chmask;	/* playback channels mask */
2686 	int st_chmask;	/* side tone mixing channel mask */
2687 };
2688 
2689 static struct uac3_badd_profile uac3_badd_profiles[] = {
2690 	{
2691 		/*
2692 		 * BAIF, BAOF or combination of both
2693 		 * IN: Mono or Stereo cfg, Mono alt possible
2694 		 * OUT: Mono or Stereo cfg, Mono alt possible
2695 		 */
2696 		.subclass = UAC3_FUNCTION_SUBCLASS_GENERIC_IO,
2697 		.name = "GENERIC IO",
2698 		.c_chmask = -1,		/* dynamic channels */
2699 		.p_chmask = -1,		/* dynamic channels */
2700 	},
2701 	{
2702 		/* BAOF; Stereo only cfg, Mono alt possible */
2703 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADPHONE,
2704 		.name = "HEADPHONE",
2705 		.p_chmask = 3,
2706 	},
2707 	{
2708 		/* BAOF; Mono or Stereo cfg, Mono alt possible */
2709 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKER,
2710 		.name = "SPEAKER",
2711 		.p_chmask = -1,		/* dynamic channels */
2712 	},
2713 	{
2714 		/* BAIF; Mono or Stereo cfg, Mono alt possible */
2715 		.subclass = UAC3_FUNCTION_SUBCLASS_MICROPHONE,
2716 		.name = "MICROPHONE",
2717 		.c_chmask = -1,		/* dynamic channels */
2718 	},
2719 	{
2720 		/*
2721 		 * BAIOF topology
2722 		 * IN: Mono only
2723 		 * OUT: Mono or Stereo cfg, Mono alt possible
2724 		 */
2725 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET,
2726 		.name = "HEADSET",
2727 		.c_chmask = 1,
2728 		.p_chmask = -1,		/* dynamic channels */
2729 		.st_chmask = 1,
2730 	},
2731 	{
2732 		/* BAIOF; IN: Mono only; OUT: Stereo only, Mono alt possible */
2733 		.subclass = UAC3_FUNCTION_SUBCLASS_HEADSET_ADAPTER,
2734 		.name = "HEADSET ADAPTER",
2735 		.c_chmask = 1,
2736 		.p_chmask = 3,
2737 		.st_chmask = 1,
2738 	},
2739 	{
2740 		/* BAIF + BAOF; IN: Mono only; OUT: Mono only */
2741 		.subclass = UAC3_FUNCTION_SUBCLASS_SPEAKERPHONE,
2742 		.name = "SPEAKERPHONE",
2743 		.c_chmask = 1,
2744 		.p_chmask = 1,
2745 	},
2746 	{ 0 } /* terminator */
2747 };
2748 
2749 static bool uac3_badd_func_has_valid_channels(struct usb_mixer_interface *mixer,
2750 					      struct uac3_badd_profile *f,
2751 					      int c_chmask, int p_chmask)
2752 {
2753 	/*
2754 	 * If both playback/capture channels are dynamic, make sure
2755 	 * at least one channel is present
2756 	 */
2757 	if (f->c_chmask < 0 && f->p_chmask < 0) {
2758 		if (!c_chmask && !p_chmask) {
2759 			usb_audio_warn(mixer->chip, "BAAD %s: no channels?",
2760 				       f->name);
2761 			return false;
2762 		}
2763 		return true;
2764 	}
2765 
2766 	if ((f->c_chmask < 0 && !c_chmask) ||
2767 	    (f->c_chmask >= 0 && f->c_chmask != c_chmask)) {
2768 		usb_audio_warn(mixer->chip, "BAAD %s c_chmask mismatch",
2769 			       f->name);
2770 		return false;
2771 	}
2772 	if ((f->p_chmask < 0 && !p_chmask) ||
2773 	    (f->p_chmask >= 0 && f->p_chmask != p_chmask)) {
2774 		usb_audio_warn(mixer->chip, "BAAD %s p_chmask mismatch",
2775 			       f->name);
2776 		return false;
2777 	}
2778 	return true;
2779 }
2780 
2781 /*
2782  * create mixer controls for UAC3 BADD profiles
2783  *
2784  * UAC3 BADD device doesn't contain CS descriptors thus we will guess everything
2785  *
2786  * BADD device may contain Mixer Unit, which doesn't have any controls, skip it
2787  */
2788 static int snd_usb_mixer_controls_badd(struct usb_mixer_interface *mixer,
2789 				       int ctrlif)
2790 {
2791 	struct usb_device *dev = mixer->chip->dev;
2792 	struct usb_interface_assoc_descriptor *assoc;
2793 	int badd_profile = mixer->chip->badd_profile;
2794 	struct uac3_badd_profile *f;
2795 	const struct usbmix_ctl_map *map;
2796 	int p_chmask = 0, c_chmask = 0, st_chmask = 0;
2797 	int i;
2798 
2799 	assoc = usb_ifnum_to_if(dev, ctrlif)->intf_assoc;
2800 
2801 	/* Detect BADD capture/playback channels from AS EP descriptors */
2802 	for (i = 0; i < assoc->bInterfaceCount; i++) {
2803 		int intf = assoc->bFirstInterface + i;
2804 
2805 		struct usb_interface *iface;
2806 		struct usb_host_interface *alts;
2807 		struct usb_interface_descriptor *altsd;
2808 		unsigned int maxpacksize;
2809 		char dir_in;
2810 		int chmask, num;
2811 
2812 		if (intf == ctrlif)
2813 			continue;
2814 
2815 		iface = usb_ifnum_to_if(dev, intf);
2816 		num = iface->num_altsetting;
2817 
2818 		if (num < 2)
2819 			return -EINVAL;
2820 
2821 		/*
2822 		 * The number of Channels in an AudioStreaming interface
2823 		 * and the audio sample bit resolution (16 bits or 24
2824 		 * bits) can be derived from the wMaxPacketSize field in
2825 		 * the Standard AS Audio Data Endpoint descriptor in
2826 		 * Alternate Setting 1
2827 		 */
2828 		alts = &iface->altsetting[1];
2829 		altsd = get_iface_desc(alts);
2830 
2831 		if (altsd->bNumEndpoints < 1)
2832 			return -EINVAL;
2833 
2834 		/* check direction */
2835 		dir_in = (get_endpoint(alts, 0)->bEndpointAddress & USB_DIR_IN);
2836 		maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
2837 
2838 		switch (maxpacksize) {
2839 		default:
2840 			usb_audio_err(mixer->chip,
2841 				"incorrect wMaxPacketSize 0x%x for BADD profile\n",
2842 				maxpacksize);
2843 			return -EINVAL;
2844 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_16:
2845 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_16:
2846 		case UAC3_BADD_EP_MAXPSIZE_SYNC_MONO_24:
2847 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_MONO_24:
2848 			chmask = 1;
2849 			break;
2850 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_16:
2851 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_16:
2852 		case UAC3_BADD_EP_MAXPSIZE_SYNC_STEREO_24:
2853 		case UAC3_BADD_EP_MAXPSIZE_ASYNC_STEREO_24:
2854 			chmask = 3;
2855 			break;
2856 		}
2857 
2858 		if (dir_in)
2859 			c_chmask = chmask;
2860 		else
2861 			p_chmask = chmask;
2862 	}
2863 
2864 	usb_audio_dbg(mixer->chip,
2865 		"UAC3 BADD profile 0x%x: detected c_chmask=%d p_chmask=%d\n",
2866 		badd_profile, c_chmask, p_chmask);
2867 
2868 	/* check the mapping table */
2869 	for (map = uac3_badd_usbmix_ctl_maps; map->id; map++) {
2870 		if (map->id == badd_profile)
2871 			break;
2872 	}
2873 
2874 	if (!map->id)
2875 		return -EINVAL;
2876 
2877 	for (f = uac3_badd_profiles; f->name; f++) {
2878 		if (badd_profile == f->subclass)
2879 			break;
2880 	}
2881 	if (!f->name)
2882 		return -EINVAL;
2883 	if (!uac3_badd_func_has_valid_channels(mixer, f, c_chmask, p_chmask))
2884 		return -EINVAL;
2885 	st_chmask = f->st_chmask;
2886 
2887 	/* Playback */
2888 	if (p_chmask) {
2889 		/* Master channel, always writable */
2890 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
2891 				       UAC3_BADD_FU_ID2, map->map);
2892 		/* Mono/Stereo volume channels, always writable */
2893 		build_feature_ctl_badd(mixer, p_chmask, UAC_FU_VOLUME,
2894 				       UAC3_BADD_FU_ID2, map->map);
2895 	}
2896 
2897 	/* Capture */
2898 	if (c_chmask) {
2899 		/* Master channel, always writable */
2900 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
2901 				       UAC3_BADD_FU_ID5, map->map);
2902 		/* Mono/Stereo volume channels, always writable */
2903 		build_feature_ctl_badd(mixer, c_chmask, UAC_FU_VOLUME,
2904 				       UAC3_BADD_FU_ID5, map->map);
2905 	}
2906 
2907 	/* Side tone-mixing */
2908 	if (st_chmask) {
2909 		/* Master channel, always writable */
2910 		build_feature_ctl_badd(mixer, 0, UAC_FU_MUTE,
2911 				       UAC3_BADD_FU_ID7, map->map);
2912 		/* Mono volume channel, always writable */
2913 		build_feature_ctl_badd(mixer, 1, UAC_FU_VOLUME,
2914 				       UAC3_BADD_FU_ID7, map->map);
2915 	}
2916 
2917 	return 0;
2918 }
2919 
2920 /*
2921  * create mixer controls
2922  *
2923  * walk through all UAC_OUTPUT_TERMINAL descriptors to search for mixers
2924  */
2925 static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
2926 {
2927 	struct mixer_build state;
2928 	int err;
2929 	const struct usbmix_ctl_map *map;
2930 	void *p;
2931 
2932 	memset(&state, 0, sizeof(state));
2933 	state.chip = mixer->chip;
2934 	state.mixer = mixer;
2935 	state.buffer = mixer->hostif->extra;
2936 	state.buflen = mixer->hostif->extralen;
2937 
2938 	/* check the mapping table */
2939 	for (map = usbmix_ctl_maps; map->id; map++) {
2940 		if (map->id == state.chip->usb_id) {
2941 			state.map = map->map;
2942 			state.selector_map = map->selector_map;
2943 			mixer->ignore_ctl_error = map->ignore_ctl_error;
2944 			break;
2945 		}
2946 	}
2947 
2948 	p = NULL;
2949 	while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
2950 					    mixer->hostif->extralen,
2951 					    p, UAC_OUTPUT_TERMINAL)) != NULL) {
2952 		if (mixer->protocol == UAC_VERSION_1) {
2953 			struct uac1_output_terminal_descriptor *desc = p;
2954 
2955 			if (desc->bLength < sizeof(*desc))
2956 				continue; /* invalid descriptor? */
2957 			/* mark terminal ID as visited */
2958 			set_bit(desc->bTerminalID, state.unitbitmap);
2959 			state.oterm.id = desc->bTerminalID;
2960 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
2961 			state.oterm.name = desc->iTerminal;
2962 			err = parse_audio_unit(&state, desc->bSourceID);
2963 			if (err < 0 && err != -EINVAL)
2964 				return err;
2965 		} else if (mixer->protocol == UAC_VERSION_2) {
2966 			struct uac2_output_terminal_descriptor *desc = p;
2967 
2968 			if (desc->bLength < sizeof(*desc))
2969 				continue; /* invalid descriptor? */
2970 			/* mark terminal ID as visited */
2971 			set_bit(desc->bTerminalID, state.unitbitmap);
2972 			state.oterm.id = desc->bTerminalID;
2973 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
2974 			state.oterm.name = desc->iTerminal;
2975 			err = parse_audio_unit(&state, desc->bSourceID);
2976 			if (err < 0 && err != -EINVAL)
2977 				return err;
2978 
2979 			/*
2980 			 * For UAC2, use the same approach to also add the
2981 			 * clock selectors
2982 			 */
2983 			err = parse_audio_unit(&state, desc->bCSourceID);
2984 			if (err < 0 && err != -EINVAL)
2985 				return err;
2986 
2987 			if (uac_v2v3_control_is_readable(le16_to_cpu(desc->bmControls),
2988 							 UAC2_TE_CONNECTOR)) {
2989 				build_connector_control(&state, &state.oterm,
2990 							false);
2991 			}
2992 		} else {  /* UAC_VERSION_3 */
2993 			struct uac3_output_terminal_descriptor *desc = p;
2994 
2995 			if (desc->bLength < sizeof(*desc))
2996 				continue; /* invalid descriptor? */
2997 			/* mark terminal ID as visited */
2998 			set_bit(desc->bTerminalID, state.unitbitmap);
2999 			state.oterm.id = desc->bTerminalID;
3000 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
3001 			state.oterm.name = le16_to_cpu(desc->wTerminalDescrStr);
3002 			err = parse_audio_unit(&state, desc->bSourceID);
3003 			if (err < 0 && err != -EINVAL)
3004 				return err;
3005 
3006 			/*
3007 			 * For UAC3, use the same approach to also add the
3008 			 * clock selectors
3009 			 */
3010 			err = parse_audio_unit(&state, desc->bCSourceID);
3011 			if (err < 0 && err != -EINVAL)
3012 				return err;
3013 
3014 			if (uac_v2v3_control_is_readable(le32_to_cpu(desc->bmControls),
3015 							 UAC3_TE_INSERTION)) {
3016 				build_connector_control(&state, &state.oterm,
3017 							false);
3018 			}
3019 		}
3020 	}
3021 
3022 	return 0;
3023 }
3024 
3025 void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
3026 {
3027 	struct usb_mixer_elem_list *list;
3028 
3029 	for_each_mixer_elem(list, mixer, unitid) {
3030 		struct usb_mixer_elem_info *info =
3031 			mixer_elem_list_to_info(list);
3032 		/* invalidate cache, so the value is read from the device */
3033 		info->cached = 0;
3034 		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3035 			       &list->kctl->id);
3036 	}
3037 }
3038 
3039 static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
3040 				    struct usb_mixer_elem_list *list)
3041 {
3042 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3043 	static char *val_types[] = {"BOOLEAN", "INV_BOOLEAN",
3044 				    "S8", "U8", "S16", "U16"};
3045 	snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
3046 			    "channels=%i, type=\"%s\"\n", cval->head.id,
3047 			    cval->control, cval->cmask, cval->channels,
3048 			    val_types[cval->val_type]);
3049 	snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
3050 			    cval->min, cval->max, cval->dBmin, cval->dBmax);
3051 }
3052 
3053 static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
3054 				    struct snd_info_buffer *buffer)
3055 {
3056 	struct snd_usb_audio *chip = entry->private_data;
3057 	struct usb_mixer_interface *mixer;
3058 	struct usb_mixer_elem_list *list;
3059 	int unitid;
3060 
3061 	list_for_each_entry(mixer, &chip->mixer_list, list) {
3062 		snd_iprintf(buffer,
3063 			"USB Mixer: usb_id=0x%08x, ctrlif=%i, ctlerr=%i\n",
3064 				chip->usb_id, snd_usb_ctrl_intf(chip),
3065 				mixer->ignore_ctl_error);
3066 		snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
3067 		for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
3068 			for_each_mixer_elem(list, mixer, unitid) {
3069 				snd_iprintf(buffer, "  Unit: %i\n", list->id);
3070 				if (list->kctl)
3071 					snd_iprintf(buffer,
3072 						    "    Control: name=\"%s\", index=%i\n",
3073 						    list->kctl->id.name,
3074 						    list->kctl->id.index);
3075 				if (list->dump)
3076 					list->dump(buffer, list);
3077 			}
3078 		}
3079 	}
3080 }
3081 
3082 static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
3083 				       int attribute, int value, int index)
3084 {
3085 	struct usb_mixer_elem_list *list;
3086 	__u8 unitid = (index >> 8) & 0xff;
3087 	__u8 control = (value >> 8) & 0xff;
3088 	__u8 channel = value & 0xff;
3089 	unsigned int count = 0;
3090 
3091 	if (channel >= MAX_CHANNELS) {
3092 		usb_audio_dbg(mixer->chip,
3093 			"%s(): bogus channel number %d\n",
3094 			__func__, channel);
3095 		return;
3096 	}
3097 
3098 	for_each_mixer_elem(list, mixer, unitid)
3099 		count++;
3100 
3101 	if (count == 0)
3102 		return;
3103 
3104 	for_each_mixer_elem(list, mixer, unitid) {
3105 		struct usb_mixer_elem_info *info;
3106 
3107 		if (!list->kctl)
3108 			continue;
3109 
3110 		info = mixer_elem_list_to_info(list);
3111 		if (count > 1 && info->control != control)
3112 			continue;
3113 
3114 		switch (attribute) {
3115 		case UAC2_CS_CUR:
3116 			/* invalidate cache, so the value is read from the device */
3117 			if (channel)
3118 				info->cached &= ~(1 << channel);
3119 			else /* master channel */
3120 				info->cached = 0;
3121 
3122 			snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
3123 				       &info->head.kctl->id);
3124 			break;
3125 
3126 		case UAC2_CS_RANGE:
3127 			/* TODO */
3128 			break;
3129 
3130 		case UAC2_CS_MEM:
3131 			/* TODO */
3132 			break;
3133 
3134 		default:
3135 			usb_audio_dbg(mixer->chip,
3136 				"unknown attribute %d in interrupt\n",
3137 				attribute);
3138 			break;
3139 		} /* switch */
3140 	}
3141 }
3142 
3143 static void snd_usb_mixer_interrupt(struct urb *urb)
3144 {
3145 	struct usb_mixer_interface *mixer = urb->context;
3146 	int len = urb->actual_length;
3147 	int ustatus = urb->status;
3148 
3149 	if (ustatus != 0)
3150 		goto requeue;
3151 
3152 	if (mixer->protocol == UAC_VERSION_1) {
3153 		struct uac1_status_word *status;
3154 
3155 		for (status = urb->transfer_buffer;
3156 		     len >= sizeof(*status);
3157 		     len -= sizeof(*status), status++) {
3158 			dev_dbg(&urb->dev->dev, "status interrupt: %02x %02x\n",
3159 						status->bStatusType,
3160 						status->bOriginator);
3161 
3162 			/* ignore any notifications not from the control interface */
3163 			if ((status->bStatusType & UAC1_STATUS_TYPE_ORIG_MASK) !=
3164 				UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF)
3165 				continue;
3166 
3167 			if (status->bStatusType & UAC1_STATUS_TYPE_MEM_CHANGED)
3168 				snd_usb_mixer_rc_memory_change(mixer, status->bOriginator);
3169 			else
3170 				snd_usb_mixer_notify_id(mixer, status->bOriginator);
3171 		}
3172 	} else { /* UAC_VERSION_2 */
3173 		struct uac2_interrupt_data_msg *msg;
3174 
3175 		for (msg = urb->transfer_buffer;
3176 		     len >= sizeof(*msg);
3177 		     len -= sizeof(*msg), msg++) {
3178 			/* drop vendor specific and endpoint requests */
3179 			if ((msg->bInfo & UAC2_INTERRUPT_DATA_MSG_VENDOR) ||
3180 			    (msg->bInfo & UAC2_INTERRUPT_DATA_MSG_EP))
3181 				continue;
3182 
3183 			snd_usb_mixer_interrupt_v2(mixer, msg->bAttribute,
3184 						   le16_to_cpu(msg->wValue),
3185 						   le16_to_cpu(msg->wIndex));
3186 		}
3187 	}
3188 
3189 requeue:
3190 	if (ustatus != -ENOENT &&
3191 	    ustatus != -ECONNRESET &&
3192 	    ustatus != -ESHUTDOWN) {
3193 		urb->dev = mixer->chip->dev;
3194 		usb_submit_urb(urb, GFP_ATOMIC);
3195 	}
3196 }
3197 
3198 /* create the handler for the optional status interrupt endpoint */
3199 static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
3200 {
3201 	struct usb_endpoint_descriptor *ep;
3202 	void *transfer_buffer;
3203 	int buffer_length;
3204 	unsigned int epnum;
3205 
3206 	/* we need one interrupt input endpoint */
3207 	if (get_iface_desc(mixer->hostif)->bNumEndpoints < 1)
3208 		return 0;
3209 	ep = get_endpoint(mixer->hostif, 0);
3210 	if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_int(ep))
3211 		return 0;
3212 
3213 	epnum = usb_endpoint_num(ep);
3214 	buffer_length = le16_to_cpu(ep->wMaxPacketSize);
3215 	transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
3216 	if (!transfer_buffer)
3217 		return -ENOMEM;
3218 	mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
3219 	if (!mixer->urb) {
3220 		kfree(transfer_buffer);
3221 		return -ENOMEM;
3222 	}
3223 	usb_fill_int_urb(mixer->urb, mixer->chip->dev,
3224 			 usb_rcvintpipe(mixer->chip->dev, epnum),
3225 			 transfer_buffer, buffer_length,
3226 			 snd_usb_mixer_interrupt, mixer, ep->bInterval);
3227 	usb_submit_urb(mixer->urb, GFP_KERNEL);
3228 	return 0;
3229 }
3230 
3231 static int keep_iface_ctl_get(struct snd_kcontrol *kcontrol,
3232 			      struct snd_ctl_elem_value *ucontrol)
3233 {
3234 	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
3235 
3236 	ucontrol->value.integer.value[0] = mixer->chip->keep_iface;
3237 	return 0;
3238 }
3239 
3240 static int keep_iface_ctl_put(struct snd_kcontrol *kcontrol,
3241 			      struct snd_ctl_elem_value *ucontrol)
3242 {
3243 	struct usb_mixer_interface *mixer = snd_kcontrol_chip(kcontrol);
3244 	bool keep_iface = !!ucontrol->value.integer.value[0];
3245 
3246 	if (mixer->chip->keep_iface == keep_iface)
3247 		return 0;
3248 	mixer->chip->keep_iface = keep_iface;
3249 	return 1;
3250 }
3251 
3252 static const struct snd_kcontrol_new keep_iface_ctl = {
3253 	.iface = SNDRV_CTL_ELEM_IFACE_CARD,
3254 	.name = "Keep Interface",
3255 	.info = snd_ctl_boolean_mono_info,
3256 	.get = keep_iface_ctl_get,
3257 	.put = keep_iface_ctl_put,
3258 };
3259 
3260 static int create_keep_iface_ctl(struct usb_mixer_interface *mixer)
3261 {
3262 	struct snd_kcontrol *kctl = snd_ctl_new1(&keep_iface_ctl, mixer);
3263 
3264 	/* need only one control per card */
3265 	if (snd_ctl_find_id(mixer->chip->card, &kctl->id)) {
3266 		snd_ctl_free_one(kctl);
3267 		return 0;
3268 	}
3269 
3270 	return snd_ctl_add(mixer->chip->card, kctl);
3271 }
3272 
3273 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
3274 			 int ignore_error)
3275 {
3276 	static struct snd_device_ops dev_ops = {
3277 		.dev_free = snd_usb_mixer_dev_free
3278 	};
3279 	struct usb_mixer_interface *mixer;
3280 	struct snd_info_entry *entry;
3281 	int err;
3282 
3283 	strcpy(chip->card->mixername, "USB Mixer");
3284 
3285 	mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
3286 	if (!mixer)
3287 		return -ENOMEM;
3288 	mixer->chip = chip;
3289 	mixer->ignore_ctl_error = ignore_error;
3290 	mixer->id_elems = kcalloc(MAX_ID_ELEMS, sizeof(*mixer->id_elems),
3291 				  GFP_KERNEL);
3292 	if (!mixer->id_elems) {
3293 		kfree(mixer);
3294 		return -ENOMEM;
3295 	}
3296 
3297 	mixer->hostif = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
3298 	switch (get_iface_desc(mixer->hostif)->bInterfaceProtocol) {
3299 	case UAC_VERSION_1:
3300 	default:
3301 		mixer->protocol = UAC_VERSION_1;
3302 		break;
3303 	case UAC_VERSION_2:
3304 		mixer->protocol = UAC_VERSION_2;
3305 		break;
3306 	case UAC_VERSION_3:
3307 		mixer->protocol = UAC_VERSION_3;
3308 		break;
3309 	}
3310 
3311 	if (mixer->protocol == UAC_VERSION_3 &&
3312 			chip->badd_profile >= UAC3_FUNCTION_SUBCLASS_GENERIC_IO) {
3313 		if ((err = snd_usb_mixer_controls_badd(mixer, ctrlif)) < 0)
3314 			goto _error;
3315 	} else if ((err = snd_usb_mixer_controls(mixer)) < 0 ||
3316 			(err = snd_usb_mixer_status_create(mixer)) < 0) {
3317 		goto _error;
3318 	}
3319 	err = create_keep_iface_ctl(mixer);
3320 	if (err < 0)
3321 		goto _error;
3322 
3323 	snd_usb_mixer_apply_create_quirk(mixer);
3324 
3325 	err = snd_device_new(chip->card, SNDRV_DEV_CODEC, mixer, &dev_ops);
3326 	if (err < 0)
3327 		goto _error;
3328 
3329 	if (list_empty(&chip->mixer_list) &&
3330 	    !snd_card_proc_new(chip->card, "usbmixer", &entry))
3331 		snd_info_set_text_ops(entry, chip, snd_usb_mixer_proc_read);
3332 
3333 	list_add(&mixer->list, &chip->mixer_list);
3334 	return 0;
3335 
3336 _error:
3337 	snd_usb_mixer_free(mixer);
3338 	return err;
3339 }
3340 
3341 void snd_usb_mixer_disconnect(struct usb_mixer_interface *mixer)
3342 {
3343 	if (mixer->disconnected)
3344 		return;
3345 	if (mixer->urb)
3346 		usb_kill_urb(mixer->urb);
3347 	if (mixer->rc_urb)
3348 		usb_kill_urb(mixer->rc_urb);
3349 	mixer->disconnected = true;
3350 }
3351 
3352 #ifdef CONFIG_PM
3353 /* stop any bus activity of a mixer */
3354 static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
3355 {
3356 	usb_kill_urb(mixer->urb);
3357 	usb_kill_urb(mixer->rc_urb);
3358 }
3359 
3360 static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
3361 {
3362 	int err;
3363 
3364 	if (mixer->urb) {
3365 		err = usb_submit_urb(mixer->urb, GFP_NOIO);
3366 		if (err < 0)
3367 			return err;
3368 	}
3369 
3370 	return 0;
3371 }
3372 
3373 int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
3374 {
3375 	snd_usb_mixer_inactivate(mixer);
3376 	return 0;
3377 }
3378 
3379 static int restore_mixer_value(struct usb_mixer_elem_list *list)
3380 {
3381 	struct usb_mixer_elem_info *cval = mixer_elem_list_to_info(list);
3382 	int c, err, idx;
3383 
3384 	if (cval->cmask) {
3385 		idx = 0;
3386 		for (c = 0; c < MAX_CHANNELS; c++) {
3387 			if (!(cval->cmask & (1 << c)))
3388 				continue;
3389 			if (cval->cached & (1 << (c + 1))) {
3390 				err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
3391 							cval->cache_val[idx]);
3392 				if (err < 0)
3393 					return err;
3394 			}
3395 			idx++;
3396 		}
3397 	} else {
3398 		/* master */
3399 		if (cval->cached) {
3400 			err = snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
3401 			if (err < 0)
3402 				return err;
3403 		}
3404 	}
3405 
3406 	return 0;
3407 }
3408 
3409 int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume)
3410 {
3411 	struct usb_mixer_elem_list *list;
3412 	int id, err;
3413 
3414 	if (reset_resume) {
3415 		/* restore cached mixer values */
3416 		for (id = 0; id < MAX_ID_ELEMS; id++) {
3417 			for_each_mixer_elem(list, mixer, id) {
3418 				if (list->resume) {
3419 					err = list->resume(list);
3420 					if (err < 0)
3421 						return err;
3422 				}
3423 			}
3424 		}
3425 	}
3426 
3427 	snd_usb_mixer_resume_quirk(mixer);
3428 
3429 	return snd_usb_mixer_activate(mixer);
3430 }
3431 #endif
3432 
3433 void snd_usb_mixer_elem_init_std(struct usb_mixer_elem_list *list,
3434 				 struct usb_mixer_interface *mixer,
3435 				 int unitid)
3436 {
3437 	list->mixer = mixer;
3438 	list->id = unitid;
3439 	list->dump = snd_usb_mixer_dump_cval;
3440 #ifdef CONFIG_PM
3441 	list->resume = restore_mixer_value;
3442 #endif
3443 }
3444