xref: /openbmc/linux/sound/usb/mixer.c (revision c2992b19)
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 
55 #include <sound/core.h>
56 #include <sound/control.h>
57 #include <sound/hwdep.h>
58 #include <sound/info.h>
59 #include <sound/tlv.h>
60 
61 #include "usbaudio.h"
62 #include "mixer.h"
63 #include "helper.h"
64 #include "mixer_quirks.h"
65 #include "power.h"
66 
67 #define MAX_ID_ELEMS	256
68 
69 struct usb_audio_term {
70 	int id;
71 	int type;
72 	int channels;
73 	unsigned int chconfig;
74 	int name;
75 };
76 
77 struct usbmix_name_map;
78 
79 struct mixer_build {
80 	struct snd_usb_audio *chip;
81 	struct usb_mixer_interface *mixer;
82 	unsigned char *buffer;
83 	unsigned int buflen;
84 	DECLARE_BITMAP(unitbitmap, MAX_ID_ELEMS);
85 	struct usb_audio_term oterm;
86 	const struct usbmix_name_map *map;
87 	const struct usbmix_selector_map *selector_map;
88 };
89 
90 /*E-mu 0202/0404/0204 eXtension Unit(XU) control*/
91 enum {
92 	USB_XU_CLOCK_RATE 		= 0xe301,
93 	USB_XU_CLOCK_SOURCE		= 0xe302,
94 	USB_XU_DIGITAL_IO_STATUS	= 0xe303,
95 	USB_XU_DEVICE_OPTIONS		= 0xe304,
96 	USB_XU_DIRECT_MONITORING	= 0xe305,
97 	USB_XU_METERING			= 0xe306
98 };
99 enum {
100 	USB_XU_CLOCK_SOURCE_SELECTOR = 0x02,	/* clock source*/
101 	USB_XU_CLOCK_RATE_SELECTOR = 0x03,	/* clock rate */
102 	USB_XU_DIGITAL_FORMAT_SELECTOR = 0x01,	/* the spdif format */
103 	USB_XU_SOFT_LIMIT_SELECTOR = 0x03	/* soft limiter */
104 };
105 
106 /*
107  * manual mapping of mixer names
108  * if the mixer topology is too complicated and the parsed names are
109  * ambiguous, add the entries in usbmixer_maps.c.
110  */
111 #include "mixer_maps.c"
112 
113 static const struct usbmix_name_map *
114 find_map(struct mixer_build *state, int unitid, int control)
115 {
116 	const struct usbmix_name_map *p = state->map;
117 
118 	if (!p)
119 		return NULL;
120 
121 	for (p = state->map; p->id; p++) {
122 		if (p->id == unitid &&
123 		    (!control || !p->control || control == p->control))
124 			return p;
125 	}
126 	return NULL;
127 }
128 
129 /* get the mapped name if the unit matches */
130 static int
131 check_mapped_name(const struct usbmix_name_map *p, char *buf, int buflen)
132 {
133 	if (!p || !p->name)
134 		return 0;
135 
136 	buflen--;
137 	return strlcpy(buf, p->name, buflen);
138 }
139 
140 /* ignore the error value if ignore_ctl_error flag is set */
141 #define filter_error(cval, err) \
142 	((cval)->head.mixer->ignore_ctl_error ? 0 : (err))
143 
144 /* check whether the control should be ignored */
145 static inline int
146 check_ignored_ctl(const struct usbmix_name_map *p)
147 {
148 	if (!p || p->name || p->dB)
149 		return 0;
150 	return 1;
151 }
152 
153 /* dB mapping */
154 static inline void check_mapped_dB(const struct usbmix_name_map *p,
155 				   struct usb_mixer_elem_info *cval)
156 {
157 	if (p && p->dB) {
158 		cval->dBmin = p->dB->min;
159 		cval->dBmax = p->dB->max;
160 		cval->initialized = 1;
161 	}
162 }
163 
164 /* get the mapped selector source name */
165 static int check_mapped_selector_name(struct mixer_build *state, int unitid,
166 				      int index, char *buf, int buflen)
167 {
168 	const struct usbmix_selector_map *p;
169 
170 	if (!state->selector_map)
171 		return 0;
172 	for (p = state->selector_map; p->id; p++) {
173 		if (p->id == unitid && index < p->count)
174 			return strlcpy(buf, p->names[index], buflen);
175 	}
176 	return 0;
177 }
178 
179 /*
180  * find an audio control unit with the given unit id
181  */
182 static void *find_audio_control_unit(struct mixer_build *state,
183 				     unsigned char unit)
184 {
185 	/* we just parse the header */
186 	struct uac_feature_unit_descriptor *hdr = NULL;
187 
188 	while ((hdr = snd_usb_find_desc(state->buffer, state->buflen, hdr,
189 					USB_DT_CS_INTERFACE)) != NULL) {
190 		if (hdr->bLength >= 4 &&
191 		    hdr->bDescriptorSubtype >= UAC_INPUT_TERMINAL &&
192 		    hdr->bDescriptorSubtype <= UAC2_SAMPLE_RATE_CONVERTER &&
193 		    hdr->bUnitID == unit)
194 			return hdr;
195 	}
196 
197 	return NULL;
198 }
199 
200 /*
201  * copy a string with the given id
202  */
203 static int snd_usb_copy_string_desc(struct mixer_build *state,
204 				    int index, char *buf, int maxlen)
205 {
206 	int len = usb_string(state->chip->dev, index, buf, maxlen - 1);
207 	buf[len] = 0;
208 	return len;
209 }
210 
211 /*
212  * convert from the byte/word on usb descriptor to the zero-based integer
213  */
214 static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
215 {
216 	switch (cval->val_type) {
217 	case USB_MIXER_BOOLEAN:
218 		return !!val;
219 	case USB_MIXER_INV_BOOLEAN:
220 		return !val;
221 	case USB_MIXER_U8:
222 		val &= 0xff;
223 		break;
224 	case USB_MIXER_S8:
225 		val &= 0xff;
226 		if (val >= 0x80)
227 			val -= 0x100;
228 		break;
229 	case USB_MIXER_U16:
230 		val &= 0xffff;
231 		break;
232 	case USB_MIXER_S16:
233 		val &= 0xffff;
234 		if (val >= 0x8000)
235 			val -= 0x10000;
236 		break;
237 	}
238 	return val;
239 }
240 
241 /*
242  * convert from the zero-based int to the byte/word for usb descriptor
243  */
244 static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
245 {
246 	switch (cval->val_type) {
247 	case USB_MIXER_BOOLEAN:
248 		return !!val;
249 	case USB_MIXER_INV_BOOLEAN:
250 		return !val;
251 	case USB_MIXER_S8:
252 	case USB_MIXER_U8:
253 		return val & 0xff;
254 	case USB_MIXER_S16:
255 	case USB_MIXER_U16:
256 		return val & 0xffff;
257 	}
258 	return 0; /* not reached */
259 }
260 
261 static int get_relative_value(struct usb_mixer_elem_info *cval, int val)
262 {
263 	if (!cval->res)
264 		cval->res = 1;
265 	if (val < cval->min)
266 		return 0;
267 	else if (val >= cval->max)
268 		return (cval->max - cval->min + cval->res - 1) / cval->res;
269 	else
270 		return (val - cval->min) / cval->res;
271 }
272 
273 static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
274 {
275 	if (val < 0)
276 		return cval->min;
277 	if (!cval->res)
278 		cval->res = 1;
279 	val *= cval->res;
280 	val += cval->min;
281 	if (val > cval->max)
282 		return cval->max;
283 	return val;
284 }
285 
286 static int uac2_ctl_value_size(int val_type)
287 {
288 	switch (val_type) {
289 	case USB_MIXER_S32:
290 	case USB_MIXER_U32:
291 		return 4;
292 	case USB_MIXER_S16:
293 	case USB_MIXER_U16:
294 		return 2;
295 	default:
296 		return 1;
297 	}
298 	return 0; /* unreachable */
299 }
300 
301 
302 /*
303  * retrieve a mixer value
304  */
305 
306 static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request,
307 			    int validx, int *value_ret)
308 {
309 	struct snd_usb_audio *chip = cval->head.mixer->chip;
310 	unsigned char buf[2];
311 	int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
312 	int timeout = 10;
313 	int idx = 0, err;
314 
315 	err = snd_usb_lock_shutdown(chip);
316 	if (err < 0)
317 		return -EIO;
318 
319 	while (timeout-- > 0) {
320 		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
321 		err = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
322 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
323 				      validx, idx, buf, val_len);
324 		if (err >= val_len) {
325 			*value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
326 			err = 0;
327 			goto out;
328 		} else if (err == -ETIMEDOUT) {
329 			goto out;
330 		}
331 	}
332 	usb_audio_dbg(chip,
333 		"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
334 		request, validx, idx, cval->val_type);
335 	err = -EINVAL;
336 
337  out:
338 	snd_usb_unlock_shutdown(chip);
339 	return err;
340 }
341 
342 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
343 			    int validx, int *value_ret)
344 {
345 	struct snd_usb_audio *chip = cval->head.mixer->chip;
346 	unsigned char buf[4 + 3 * sizeof(__u32)]; /* enough space for one range */
347 	unsigned char *val;
348 	int idx = 0, ret, size;
349 	__u8 bRequest;
350 
351 	if (request == UAC_GET_CUR) {
352 		bRequest = UAC2_CS_CUR;
353 		size = uac2_ctl_value_size(cval->val_type);
354 	} else {
355 		bRequest = UAC2_CS_RANGE;
356 		size = sizeof(buf);
357 	}
358 
359 	memset(buf, 0, sizeof(buf));
360 
361 	ret = snd_usb_lock_shutdown(chip) ? -EIO : 0;
362 	if (ret)
363 		goto error;
364 
365 	idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
366 	ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
367 			      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
368 			      validx, idx, buf, size);
369 	snd_usb_unlock_shutdown(chip);
370 
371 	if (ret < 0) {
372 error:
373 		usb_audio_err(chip,
374 			"cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
375 			request, validx, idx, cval->val_type);
376 		return ret;
377 	}
378 
379 	/* FIXME: how should we handle multiple triplets here? */
380 
381 	switch (request) {
382 	case UAC_GET_CUR:
383 		val = buf;
384 		break;
385 	case UAC_GET_MIN:
386 		val = buf + sizeof(__u16);
387 		break;
388 	case UAC_GET_MAX:
389 		val = buf + sizeof(__u16) * 2;
390 		break;
391 	case UAC_GET_RES:
392 		val = buf + sizeof(__u16) * 3;
393 		break;
394 	default:
395 		return -EINVAL;
396 	}
397 
398 	*value_ret = convert_signed_value(cval, snd_usb_combine_bytes(val, sizeof(__u16)));
399 
400 	return 0;
401 }
402 
403 static int get_ctl_value(struct usb_mixer_elem_info *cval, int request,
404 			 int validx, int *value_ret)
405 {
406 	validx += cval->idx_off;
407 
408 	return (cval->head.mixer->protocol == UAC_VERSION_1) ?
409 		get_ctl_value_v1(cval, request, validx, value_ret) :
410 		get_ctl_value_v2(cval, request, validx, value_ret);
411 }
412 
413 static int get_cur_ctl_value(struct usb_mixer_elem_info *cval,
414 			     int validx, int *value)
415 {
416 	return get_ctl_value(cval, UAC_GET_CUR, validx, value);
417 }
418 
419 /* channel = 0: master, 1 = first channel */
420 static inline int get_cur_mix_raw(struct usb_mixer_elem_info *cval,
421 				  int channel, int *value)
422 {
423 	return get_ctl_value(cval, UAC_GET_CUR,
424 			     (cval->control << 8) | channel,
425 			     value);
426 }
427 
428 int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
429 			     int channel, int index, int *value)
430 {
431 	int err;
432 
433 	if (cval->cached & (1 << channel)) {
434 		*value = cval->cache_val[index];
435 		return 0;
436 	}
437 	err = get_cur_mix_raw(cval, channel, value);
438 	if (err < 0) {
439 		if (!cval->head.mixer->ignore_ctl_error)
440 			usb_audio_dbg(cval->head.mixer->chip,
441 				"cannot get current value for control %d ch %d: err = %d\n",
442 				      cval->control, channel, err);
443 		return err;
444 	}
445 	cval->cached |= 1 << channel;
446 	cval->cache_val[index] = *value;
447 	return 0;
448 }
449 
450 /*
451  * set a mixer value
452  */
453 
454 int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
455 				int request, int validx, int value_set)
456 {
457 	struct snd_usb_audio *chip = cval->head.mixer->chip;
458 	unsigned char buf[4];
459 	int idx = 0, val_len, err, timeout = 10;
460 
461 	validx += cval->idx_off;
462 
463 	if (cval->head.mixer->protocol == UAC_VERSION_1) {
464 		val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
465 	} else { /* UAC_VERSION_2 */
466 		val_len = uac2_ctl_value_size(cval->val_type);
467 
468 		/* FIXME */
469 		if (request != UAC_SET_CUR) {
470 			usb_audio_dbg(chip, "RANGE setting not yet supported\n");
471 			return -EINVAL;
472 		}
473 
474 		request = UAC2_CS_CUR;
475 	}
476 
477 	value_set = convert_bytes_value(cval, value_set);
478 	buf[0] = value_set & 0xff;
479 	buf[1] = (value_set >> 8) & 0xff;
480 	buf[2] = (value_set >> 16) & 0xff;
481 	buf[3] = (value_set >> 24) & 0xff;
482 
483 	err = snd_usb_lock_shutdown(chip);
484 	if (err < 0)
485 		return -EIO;
486 
487 	while (timeout-- > 0) {
488 		idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
489 		err = snd_usb_ctl_msg(chip->dev,
490 				      usb_sndctrlpipe(chip->dev, 0), request,
491 				      USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
492 				      validx, idx, buf, val_len);
493 		if (err >= 0) {
494 			err = 0;
495 			goto out;
496 		} else if (err == -ETIMEDOUT) {
497 			goto out;
498 		}
499 	}
500 	usb_audio_dbg(chip, "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
501 		      request, validx, idx, cval->val_type, buf[0], buf[1]);
502 	err = -EINVAL;
503 
504  out:
505 	snd_usb_unlock_shutdown(chip);
506 	return err;
507 }
508 
509 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval,
510 			     int validx, int value)
511 {
512 	return snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, validx, value);
513 }
514 
515 int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
516 			     int index, int value)
517 {
518 	int err;
519 	unsigned int read_only = (channel == 0) ?
520 		cval->master_readonly :
521 		cval->ch_readonly & (1 << (channel - 1));
522 
523 	if (read_only) {
524 		usb_audio_dbg(cval->head.mixer->chip,
525 			      "%s(): channel %d of control %d is read_only\n",
526 			    __func__, channel, cval->control);
527 		return 0;
528 	}
529 
530 	err = snd_usb_mixer_set_ctl_value(cval,
531 					  UAC_SET_CUR, (cval->control << 8) | channel,
532 					  value);
533 	if (err < 0)
534 		return err;
535 	cval->cached |= 1 << channel;
536 	cval->cache_val[index] = value;
537 	return 0;
538 }
539 
540 /*
541  * TLV callback for mixer volume controls
542  */
543 int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
544 			 unsigned int size, unsigned int __user *_tlv)
545 {
546 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
547 	DECLARE_TLV_DB_MINMAX(scale, 0, 0);
548 
549 	if (size < sizeof(scale))
550 		return -ENOMEM;
551 	scale[2] = cval->dBmin;
552 	scale[3] = cval->dBmax;
553 	if (copy_to_user(_tlv, scale, sizeof(scale)))
554 		return -EFAULT;
555 	return 0;
556 }
557 
558 /*
559  * parser routines begin here...
560  */
561 
562 static int parse_audio_unit(struct mixer_build *state, int unitid);
563 
564 
565 /*
566  * check if the input/output channel routing is enabled on the given bitmap.
567  * used for mixer unit parser
568  */
569 static int check_matrix_bitmap(unsigned char *bmap,
570 			       int ich, int och, int num_outs)
571 {
572 	int idx = ich * num_outs + och;
573 	return bmap[idx >> 3] & (0x80 >> (idx & 7));
574 }
575 
576 /*
577  * add an alsa control element
578  * search and increment the index until an empty slot is found.
579  *
580  * if failed, give up and free the control instance.
581  */
582 
583 int snd_usb_mixer_add_control(struct usb_mixer_elem_list *list,
584 			      struct snd_kcontrol *kctl)
585 {
586 	struct usb_mixer_interface *mixer = list->mixer;
587 	int err;
588 
589 	while (snd_ctl_find_id(mixer->chip->card, &kctl->id))
590 		kctl->id.index++;
591 	if ((err = snd_ctl_add(mixer->chip->card, kctl)) < 0) {
592 		usb_audio_dbg(mixer->chip, "cannot add control (err = %d)\n",
593 			      err);
594 		return err;
595 	}
596 	list->kctl = kctl;
597 	list->next_id_elem = mixer->id_elems[list->id];
598 	mixer->id_elems[list->id] = list;
599 	return 0;
600 }
601 
602 /*
603  * get a terminal name string
604  */
605 
606 static struct iterm_name_combo {
607 	int type;
608 	char *name;
609 } iterm_names[] = {
610 	{ 0x0300, "Output" },
611 	{ 0x0301, "Speaker" },
612 	{ 0x0302, "Headphone" },
613 	{ 0x0303, "HMD Audio" },
614 	{ 0x0304, "Desktop Speaker" },
615 	{ 0x0305, "Room Speaker" },
616 	{ 0x0306, "Com Speaker" },
617 	{ 0x0307, "LFE" },
618 	{ 0x0600, "External In" },
619 	{ 0x0601, "Analog In" },
620 	{ 0x0602, "Digital In" },
621 	{ 0x0603, "Line" },
622 	{ 0x0604, "Legacy In" },
623 	{ 0x0605, "IEC958 In" },
624 	{ 0x0606, "1394 DA Stream" },
625 	{ 0x0607, "1394 DV Stream" },
626 	{ 0x0700, "Embedded" },
627 	{ 0x0701, "Noise Source" },
628 	{ 0x0702, "Equalization Noise" },
629 	{ 0x0703, "CD" },
630 	{ 0x0704, "DAT" },
631 	{ 0x0705, "DCC" },
632 	{ 0x0706, "MiniDisk" },
633 	{ 0x0707, "Analog Tape" },
634 	{ 0x0708, "Phonograph" },
635 	{ 0x0709, "VCR Audio" },
636 	{ 0x070a, "Video Disk Audio" },
637 	{ 0x070b, "DVD Audio" },
638 	{ 0x070c, "TV Tuner Audio" },
639 	{ 0x070d, "Satellite Rec Audio" },
640 	{ 0x070e, "Cable Tuner Audio" },
641 	{ 0x070f, "DSS Audio" },
642 	{ 0x0710, "Radio Receiver" },
643 	{ 0x0711, "Radio Transmitter" },
644 	{ 0x0712, "Multi-Track Recorder" },
645 	{ 0x0713, "Synthesizer" },
646 	{ 0 },
647 };
648 
649 static int get_term_name(struct mixer_build *state, struct usb_audio_term *iterm,
650 			 unsigned char *name, int maxlen, int term_only)
651 {
652 	struct iterm_name_combo *names;
653 
654 	if (iterm->name)
655 		return snd_usb_copy_string_desc(state, iterm->name,
656 						name, maxlen);
657 
658 	/* virtual type - not a real terminal */
659 	if (iterm->type >> 16) {
660 		if (term_only)
661 			return 0;
662 		switch (iterm->type >> 16) {
663 		case UAC_SELECTOR_UNIT:
664 			strcpy(name, "Selector");
665 			return 8;
666 		case UAC1_PROCESSING_UNIT:
667 			strcpy(name, "Process Unit");
668 			return 12;
669 		case UAC1_EXTENSION_UNIT:
670 			strcpy(name, "Ext Unit");
671 			return 8;
672 		case UAC_MIXER_UNIT:
673 			strcpy(name, "Mixer");
674 			return 5;
675 		default:
676 			return sprintf(name, "Unit %d", iterm->id);
677 		}
678 	}
679 
680 	switch (iterm->type & 0xff00) {
681 	case 0x0100:
682 		strcpy(name, "PCM");
683 		return 3;
684 	case 0x0200:
685 		strcpy(name, "Mic");
686 		return 3;
687 	case 0x0400:
688 		strcpy(name, "Headset");
689 		return 7;
690 	case 0x0500:
691 		strcpy(name, "Phone");
692 		return 5;
693 	}
694 
695 	for (names = iterm_names; names->type; names++) {
696 		if (names->type == iterm->type) {
697 			strcpy(name, names->name);
698 			return strlen(names->name);
699 		}
700 	}
701 
702 	return 0;
703 }
704 
705 /*
706  * parse the source unit recursively until it reaches to a terminal
707  * or a branched unit.
708  */
709 static int check_input_term(struct mixer_build *state, int id,
710 			    struct usb_audio_term *term)
711 {
712 	int err;
713 	void *p1;
714 
715 	memset(term, 0, sizeof(*term));
716 	while ((p1 = find_audio_control_unit(state, id)) != NULL) {
717 		unsigned char *hdr = p1;
718 		term->id = id;
719 		switch (hdr[2]) {
720 		case UAC_INPUT_TERMINAL:
721 			if (state->mixer->protocol == UAC_VERSION_1) {
722 				struct uac_input_terminal_descriptor *d = p1;
723 				term->type = le16_to_cpu(d->wTerminalType);
724 				term->channels = d->bNrChannels;
725 				term->chconfig = le16_to_cpu(d->wChannelConfig);
726 				term->name = d->iTerminal;
727 			} else { /* UAC_VERSION_2 */
728 				struct uac2_input_terminal_descriptor *d = p1;
729 
730 				/* call recursively to verify that the
731 				 * referenced clock entity is valid */
732 				err = check_input_term(state, d->bCSourceID, term);
733 				if (err < 0)
734 					return err;
735 
736 				/* save input term properties after recursion,
737 				 * to ensure they are not overriden by the
738 				 * recursion calls */
739 				term->id = id;
740 				term->type = le16_to_cpu(d->wTerminalType);
741 				term->channels = d->bNrChannels;
742 				term->chconfig = le32_to_cpu(d->bmChannelConfig);
743 				term->name = d->iTerminal;
744 			}
745 			return 0;
746 		case UAC_FEATURE_UNIT: {
747 			/* the header is the same for v1 and v2 */
748 			struct uac_feature_unit_descriptor *d = p1;
749 			id = d->bSourceID;
750 			break; /* continue to parse */
751 		}
752 		case UAC_MIXER_UNIT: {
753 			struct uac_mixer_unit_descriptor *d = p1;
754 			term->type = d->bDescriptorSubtype << 16; /* virtual type */
755 			term->channels = uac_mixer_unit_bNrChannels(d);
756 			term->chconfig = uac_mixer_unit_wChannelConfig(d, state->mixer->protocol);
757 			term->name = uac_mixer_unit_iMixer(d);
758 			return 0;
759 		}
760 		case UAC_SELECTOR_UNIT:
761 		case UAC2_CLOCK_SELECTOR: {
762 			struct uac_selector_unit_descriptor *d = p1;
763 			/* call recursively to retrieve the channel info */
764 			err = check_input_term(state, d->baSourceID[0], term);
765 			if (err < 0)
766 				return err;
767 			term->type = d->bDescriptorSubtype << 16; /* virtual type */
768 			term->id = id;
769 			term->name = uac_selector_unit_iSelector(d);
770 			return 0;
771 		}
772 		case UAC1_PROCESSING_UNIT:
773 		case UAC1_EXTENSION_UNIT:
774 		/* UAC2_PROCESSING_UNIT_V2 */
775 		/* UAC2_EFFECT_UNIT */
776 		case UAC2_EXTENSION_UNIT_V2: {
777 			struct uac_processing_unit_descriptor *d = p1;
778 
779 			if (state->mixer->protocol == UAC_VERSION_2 &&
780 				hdr[2] == UAC2_EFFECT_UNIT) {
781 				/* UAC2/UAC1 unit IDs overlap here in an
782 				 * uncompatible way. Ignore this unit for now.
783 				 */
784 				return 0;
785 			}
786 
787 			if (d->bNrInPins) {
788 				id = d->baSourceID[0];
789 				break; /* continue to parse */
790 			}
791 			term->type = d->bDescriptorSubtype << 16; /* virtual type */
792 			term->channels = uac_processing_unit_bNrChannels(d);
793 			term->chconfig = uac_processing_unit_wChannelConfig(d, state->mixer->protocol);
794 			term->name = uac_processing_unit_iProcessing(d, state->mixer->protocol);
795 			return 0;
796 		}
797 		case UAC2_CLOCK_SOURCE: {
798 			struct uac_clock_source_descriptor *d = p1;
799 			term->type = d->bDescriptorSubtype << 16; /* virtual type */
800 			term->id = id;
801 			term->name = d->iClockSource;
802 			return 0;
803 		}
804 		default:
805 			return -ENODEV;
806 		}
807 	}
808 	return -ENODEV;
809 }
810 
811 /*
812  * Feature Unit
813  */
814 
815 /* feature unit control information */
816 struct usb_feature_control_info {
817 	const char *name;
818 	int type;	/* data type for uac1 */
819 	int type_uac2;	/* data type for uac2 if different from uac1, else -1 */
820 };
821 
822 static struct usb_feature_control_info audio_feature_info[] = {
823 	{ "Mute",			USB_MIXER_INV_BOOLEAN, -1 },
824 	{ "Volume",			USB_MIXER_S16, -1 },
825 	{ "Tone Control - Bass",	USB_MIXER_S8, -1 },
826 	{ "Tone Control - Mid",		USB_MIXER_S8, -1 },
827 	{ "Tone Control - Treble",	USB_MIXER_S8, -1 },
828 	{ "Graphic Equalizer",		USB_MIXER_S8, -1 }, /* FIXME: not implemeted yet */
829 	{ "Auto Gain Control",		USB_MIXER_BOOLEAN, -1 },
830 	{ "Delay Control",		USB_MIXER_U16, USB_MIXER_U32 },
831 	{ "Bass Boost",			USB_MIXER_BOOLEAN, -1 },
832 	{ "Loudness",			USB_MIXER_BOOLEAN, -1 },
833 	/* UAC2 specific */
834 	{ "Input Gain Control",		USB_MIXER_S16, -1 },
835 	{ "Input Gain Pad Control",	USB_MIXER_S16, -1 },
836 	{ "Phase Inverter Control",	USB_MIXER_BOOLEAN, -1 },
837 };
838 
839 /* private_free callback */
840 void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
841 {
842 	kfree(kctl->private_data);
843 	kctl->private_data = NULL;
844 }
845 
846 /*
847  * interface to ALSA control for feature/mixer units
848  */
849 
850 /* volume control quirks */
851 static void volume_control_quirks(struct usb_mixer_elem_info *cval,
852 				  struct snd_kcontrol *kctl)
853 {
854 	struct snd_usb_audio *chip = cval->head.mixer->chip;
855 	switch (chip->usb_id) {
856 	case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
857 	case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
858 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
859 			cval->min = 0x0000;
860 			cval->max = 0xffff;
861 			cval->res = 0x00e6;
862 			break;
863 		}
864 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
865 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
866 			cval->min = 0x00;
867 			cval->max = 0xff;
868 			break;
869 		}
870 		if (strstr(kctl->id.name, "Effect Return") != NULL) {
871 			cval->min = 0xb706;
872 			cval->max = 0xff7b;
873 			cval->res = 0x0073;
874 			break;
875 		}
876 		if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
877 			(strstr(kctl->id.name, "Effect Send") != NULL)) {
878 			cval->min = 0xb5fb; /* -73 dB = 0xb6ff */
879 			cval->max = 0xfcfe;
880 			cval->res = 0x0073;
881 		}
882 		break;
883 
884 	case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */
885 	case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
886 		if (strcmp(kctl->id.name, "Effect Duration") == 0) {
887 			usb_audio_info(chip,
888 				       "set quirk for FTU Effect Duration\n");
889 			cval->min = 0x0000;
890 			cval->max = 0x7f00;
891 			cval->res = 0x0100;
892 			break;
893 		}
894 		if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
895 		    strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
896 			usb_audio_info(chip,
897 				       "set quirks for FTU Effect Feedback/Volume\n");
898 			cval->min = 0x00;
899 			cval->max = 0x7f;
900 			break;
901 		}
902 		break;
903 
904 	case USB_ID(0x0471, 0x0101):
905 	case USB_ID(0x0471, 0x0104):
906 	case USB_ID(0x0471, 0x0105):
907 	case USB_ID(0x0672, 0x1041):
908 	/* quirk for UDA1321/N101.
909 	 * note that detection between firmware 2.1.1.7 (N101)
910 	 * and later 2.1.1.21 is not very clear from datasheets.
911 	 * I hope that the min value is -15360 for newer firmware --jk
912 	 */
913 		if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
914 		    cval->min == -15616) {
915 			usb_audio_info(chip,
916 				 "set volume quirk for UDA1321/N101 chip\n");
917 			cval->max = -256;
918 		}
919 		break;
920 
921 	case USB_ID(0x046d, 0x09a4):
922 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
923 			usb_audio_info(chip,
924 				"set volume quirk for QuickCam E3500\n");
925 			cval->min = 6080;
926 			cval->max = 8768;
927 			cval->res = 192;
928 		}
929 		break;
930 
931 	case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
932 	case USB_ID(0x046d, 0x0808):
933 	case USB_ID(0x046d, 0x0809):
934 	case USB_ID(0x046d, 0x0819): /* Logitech Webcam C210 */
935 	case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
936 	case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
937 	case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
938 	case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
939 	case USB_ID(0x046d, 0x08ca): /* Logitech Quickcam Fusion */
940 	case USB_ID(0x046d, 0x0991):
941 	case USB_ID(0x046d, 0x09a2): /* QuickCam Communicate Deluxe/S7500 */
942 	/* Most audio usb devices lie about volume resolution.
943 	 * Most Logitech webcams have res = 384.
944 	 * Probably there is some logitech magic behind this number --fishor
945 	 */
946 		if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
947 			usb_audio_info(chip,
948 				"set resolution quirk: cval->res = 384\n");
949 			cval->res = 384;
950 		}
951 		break;
952 	}
953 }
954 
955 /*
956  * retrieve the minimum and maximum values for the specified control
957  */
958 static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
959 				   int default_min, struct snd_kcontrol *kctl)
960 {
961 	/* for failsafe */
962 	cval->min = default_min;
963 	cval->max = cval->min + 1;
964 	cval->res = 1;
965 	cval->dBmin = cval->dBmax = 0;
966 
967 	if (cval->val_type == USB_MIXER_BOOLEAN ||
968 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
969 		cval->initialized = 1;
970 	} else {
971 		int minchn = 0;
972 		if (cval->cmask) {
973 			int i;
974 			for (i = 0; i < MAX_CHANNELS; i++)
975 				if (cval->cmask & (1 << i)) {
976 					minchn = i + 1;
977 					break;
978 				}
979 		}
980 		if (get_ctl_value(cval, UAC_GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
981 		    get_ctl_value(cval, UAC_GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
982 			usb_audio_err(cval->head.mixer->chip,
983 				      "%d:%d: cannot get min/max values for control %d (id %d)\n",
984 				   cval->head.id, snd_usb_ctrl_intf(cval->head.mixer->chip),
985 							       cval->control, cval->head.id);
986 			return -EINVAL;
987 		}
988 		if (get_ctl_value(cval, UAC_GET_RES,
989 				  (cval->control << 8) | minchn,
990 				  &cval->res) < 0) {
991 			cval->res = 1;
992 		} else {
993 			int last_valid_res = cval->res;
994 
995 			while (cval->res > 1) {
996 				if (snd_usb_mixer_set_ctl_value(cval, UAC_SET_RES,
997 								(cval->control << 8) | minchn,
998 								cval->res / 2) < 0)
999 					break;
1000 				cval->res /= 2;
1001 			}
1002 			if (get_ctl_value(cval, UAC_GET_RES,
1003 					  (cval->control << 8) | minchn, &cval->res) < 0)
1004 				cval->res = last_valid_res;
1005 		}
1006 		if (cval->res == 0)
1007 			cval->res = 1;
1008 
1009 		/* Additional checks for the proper resolution
1010 		 *
1011 		 * Some devices report smaller resolutions than actually
1012 		 * reacting.  They don't return errors but simply clip
1013 		 * to the lower aligned value.
1014 		 */
1015 		if (cval->min + cval->res < cval->max) {
1016 			int last_valid_res = cval->res;
1017 			int saved, test, check;
1018 			get_cur_mix_raw(cval, minchn, &saved);
1019 			for (;;) {
1020 				test = saved;
1021 				if (test < cval->max)
1022 					test += cval->res;
1023 				else
1024 					test -= cval->res;
1025 				if (test < cval->min || test > cval->max ||
1026 				    snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||
1027 				    get_cur_mix_raw(cval, minchn, &check)) {
1028 					cval->res = last_valid_res;
1029 					break;
1030 				}
1031 				if (test == check)
1032 					break;
1033 				cval->res *= 2;
1034 			}
1035 			snd_usb_set_cur_mix_value(cval, minchn, 0, saved);
1036 		}
1037 
1038 		cval->initialized = 1;
1039 	}
1040 
1041 	if (kctl)
1042 		volume_control_quirks(cval, kctl);
1043 
1044 	/* USB descriptions contain the dB scale in 1/256 dB unit
1045 	 * while ALSA TLV contains in 1/100 dB unit
1046 	 */
1047 	cval->dBmin = (convert_signed_value(cval, cval->min) * 100) / 256;
1048 	cval->dBmax = (convert_signed_value(cval, cval->max) * 100) / 256;
1049 	if (cval->dBmin > cval->dBmax) {
1050 		/* something is wrong; assume it's either from/to 0dB */
1051 		if (cval->dBmin < 0)
1052 			cval->dBmax = 0;
1053 		else if (cval->dBmin > 0)
1054 			cval->dBmin = 0;
1055 		if (cval->dBmin > cval->dBmax) {
1056 			/* totally crap, return an error */
1057 			return -EINVAL;
1058 		}
1059 	}
1060 
1061 	return 0;
1062 }
1063 
1064 #define get_min_max(cval, def)	get_min_max_with_quirks(cval, def, NULL)
1065 
1066 /* get a feature/mixer unit info */
1067 static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol,
1068 				  struct snd_ctl_elem_info *uinfo)
1069 {
1070 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1071 
1072 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1073 	    cval->val_type == USB_MIXER_INV_BOOLEAN)
1074 		uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1075 	else
1076 		uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1077 	uinfo->count = cval->channels;
1078 	if (cval->val_type == USB_MIXER_BOOLEAN ||
1079 	    cval->val_type == USB_MIXER_INV_BOOLEAN) {
1080 		uinfo->value.integer.min = 0;
1081 		uinfo->value.integer.max = 1;
1082 	} else {
1083 		if (!cval->initialized) {
1084 			get_min_max_with_quirks(cval, 0, kcontrol);
1085 			if (cval->initialized && cval->dBmin >= cval->dBmax) {
1086 				kcontrol->vd[0].access &=
1087 					~(SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1088 					  SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
1089 				snd_ctl_notify(cval->head.mixer->chip->card,
1090 					       SNDRV_CTL_EVENT_MASK_INFO,
1091 					       &kcontrol->id);
1092 			}
1093 		}
1094 		uinfo->value.integer.min = 0;
1095 		uinfo->value.integer.max =
1096 			(cval->max - cval->min + cval->res - 1) / cval->res;
1097 	}
1098 	return 0;
1099 }
1100 
1101 /* get the current value from feature/mixer unit */
1102 static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol,
1103 				 struct snd_ctl_elem_value *ucontrol)
1104 {
1105 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1106 	int c, cnt, val, err;
1107 
1108 	ucontrol->value.integer.value[0] = cval->min;
1109 	if (cval->cmask) {
1110 		cnt = 0;
1111 		for (c = 0; c < MAX_CHANNELS; c++) {
1112 			if (!(cval->cmask & (1 << c)))
1113 				continue;
1114 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &val);
1115 			if (err < 0)
1116 				return filter_error(cval, err);
1117 			val = get_relative_value(cval, val);
1118 			ucontrol->value.integer.value[cnt] = val;
1119 			cnt++;
1120 		}
1121 		return 0;
1122 	} else {
1123 		/* master channel */
1124 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1125 		if (err < 0)
1126 			return filter_error(cval, err);
1127 		val = get_relative_value(cval, val);
1128 		ucontrol->value.integer.value[0] = val;
1129 	}
1130 	return 0;
1131 }
1132 
1133 /* put the current value to feature/mixer unit */
1134 static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol,
1135 				 struct snd_ctl_elem_value *ucontrol)
1136 {
1137 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1138 	int c, cnt, val, oval, err;
1139 	int changed = 0;
1140 
1141 	if (cval->cmask) {
1142 		cnt = 0;
1143 		for (c = 0; c < MAX_CHANNELS; c++) {
1144 			if (!(cval->cmask & (1 << c)))
1145 				continue;
1146 			err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &oval);
1147 			if (err < 0)
1148 				return filter_error(cval, err);
1149 			val = ucontrol->value.integer.value[cnt];
1150 			val = get_abs_value(cval, val);
1151 			if (oval != val) {
1152 				snd_usb_set_cur_mix_value(cval, c + 1, cnt, val);
1153 				changed = 1;
1154 			}
1155 			cnt++;
1156 		}
1157 	} else {
1158 		/* master channel */
1159 		err = snd_usb_get_cur_mix_value(cval, 0, 0, &oval);
1160 		if (err < 0)
1161 			return filter_error(cval, err);
1162 		val = ucontrol->value.integer.value[0];
1163 		val = get_abs_value(cval, val);
1164 		if (val != oval) {
1165 			snd_usb_set_cur_mix_value(cval, 0, 0, val);
1166 			changed = 1;
1167 		}
1168 	}
1169 	return changed;
1170 }
1171 
1172 static struct snd_kcontrol_new usb_feature_unit_ctl = {
1173 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1174 	.name = "", /* will be filled later manually */
1175 	.info = mixer_ctl_feature_info,
1176 	.get = mixer_ctl_feature_get,
1177 	.put = mixer_ctl_feature_put,
1178 };
1179 
1180 /* the read-only variant */
1181 static const struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
1182 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1183 	.name = "", /* will be filled later manually */
1184 	.info = mixer_ctl_feature_info,
1185 	.get = mixer_ctl_feature_get,
1186 	.put = NULL,
1187 };
1188 
1189 /*
1190  * This symbol is exported in order to allow the mixer quirks to
1191  * hook up to the standard feature unit control mechanism
1192  */
1193 struct snd_kcontrol_new *snd_usb_feature_unit_ctl = &usb_feature_unit_ctl;
1194 
1195 /*
1196  * build a feature control
1197  */
1198 static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
1199 {
1200 	return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
1201 }
1202 
1203 /*
1204  * A lot of headsets/headphones have a "Speaker" mixer. Make sure we
1205  * rename it to "Headphone". We determine if something is a headphone
1206  * similar to how udev determines form factor.
1207  */
1208 static void check_no_speaker_on_headset(struct snd_kcontrol *kctl,
1209 					struct snd_card *card)
1210 {
1211 	const char *names_to_check[] = {
1212 		"Headset", "headset", "Headphone", "headphone", NULL};
1213 	const char **s;
1214 	bool found = false;
1215 
1216 	if (strcmp("Speaker", kctl->id.name))
1217 		return;
1218 
1219 	for (s = names_to_check; *s; s++)
1220 		if (strstr(card->shortname, *s)) {
1221 			found = true;
1222 			break;
1223 		}
1224 
1225 	if (!found)
1226 		return;
1227 
1228 	strlcpy(kctl->id.name, "Headphone", sizeof(kctl->id.name));
1229 }
1230 
1231 static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
1232 			      unsigned int ctl_mask, int control,
1233 			      struct usb_audio_term *iterm, int unitid,
1234 			      int readonly_mask)
1235 {
1236 	struct uac_feature_unit_descriptor *desc = raw_desc;
1237 	struct usb_feature_control_info *ctl_info;
1238 	unsigned int len = 0;
1239 	int mapped_name = 0;
1240 	int nameid = uac_feature_unit_iFeature(desc);
1241 	struct snd_kcontrol *kctl;
1242 	struct usb_mixer_elem_info *cval;
1243 	const struct usbmix_name_map *map;
1244 	unsigned int range;
1245 
1246 	control++; /* change from zero-based to 1-based value */
1247 
1248 	if (control == UAC_FU_GRAPHIC_EQUALIZER) {
1249 		/* FIXME: not supported yet */
1250 		return;
1251 	}
1252 
1253 	map = find_map(state, unitid, control);
1254 	if (check_ignored_ctl(map))
1255 		return;
1256 
1257 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1258 	if (!cval)
1259 		return;
1260 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
1261 	cval->control = control;
1262 	cval->cmask = ctl_mask;
1263 	ctl_info = &audio_feature_info[control-1];
1264 	if (state->mixer->protocol == UAC_VERSION_1)
1265 		cval->val_type = ctl_info->type;
1266 	else /* UAC_VERSION_2 */
1267 		cval->val_type = ctl_info->type_uac2 >= 0 ?
1268 			ctl_info->type_uac2 : ctl_info->type;
1269 
1270 	if (ctl_mask == 0) {
1271 		cval->channels = 1;	/* master channel */
1272 		cval->master_readonly = readonly_mask;
1273 	} else {
1274 		int i, c = 0;
1275 		for (i = 0; i < 16; i++)
1276 			if (ctl_mask & (1 << i))
1277 				c++;
1278 		cval->channels = c;
1279 		cval->ch_readonly = readonly_mask;
1280 	}
1281 
1282 	/*
1283 	 * If all channels in the mask are marked read-only, make the control
1284 	 * read-only. snd_usb_set_cur_mix_value() will check the mask again and won't
1285 	 * issue write commands to read-only channels.
1286 	 */
1287 	if (cval->channels == readonly_mask)
1288 		kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
1289 	else
1290 		kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1291 
1292 	if (!kctl) {
1293 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
1294 		kfree(cval);
1295 		return;
1296 	}
1297 	kctl->private_free = snd_usb_mixer_elem_free;
1298 
1299 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1300 	mapped_name = len != 0;
1301 	if (!len && nameid)
1302 		len = snd_usb_copy_string_desc(state, nameid,
1303 				kctl->id.name, sizeof(kctl->id.name));
1304 
1305 	switch (control) {
1306 	case UAC_FU_MUTE:
1307 	case UAC_FU_VOLUME:
1308 		/*
1309 		 * determine the control name.  the rule is:
1310 		 * - if a name id is given in descriptor, use it.
1311 		 * - if the connected input can be determined, then use the name
1312 		 *   of terminal type.
1313 		 * - if the connected output can be determined, use it.
1314 		 * - otherwise, anonymous name.
1315 		 */
1316 		if (!len) {
1317 			len = get_term_name(state, iterm, kctl->id.name,
1318 					    sizeof(kctl->id.name), 1);
1319 			if (!len)
1320 				len = get_term_name(state, &state->oterm,
1321 						    kctl->id.name,
1322 						    sizeof(kctl->id.name), 1);
1323 			if (!len)
1324 				snprintf(kctl->id.name, sizeof(kctl->id.name),
1325 					 "Feature %d", unitid);
1326 		}
1327 
1328 		if (!mapped_name)
1329 			check_no_speaker_on_headset(kctl, state->mixer->chip->card);
1330 
1331 		/*
1332 		 * determine the stream direction:
1333 		 * if the connected output is USB stream, then it's likely a
1334 		 * capture stream.  otherwise it should be playback (hopefully :)
1335 		 */
1336 		if (!mapped_name && !(state->oterm.type >> 16)) {
1337 			if ((state->oterm.type & 0xff00) == 0x0100)
1338 				append_ctl_name(kctl, " Capture");
1339 			else
1340 				append_ctl_name(kctl, " Playback");
1341 		}
1342 		append_ctl_name(kctl, control == UAC_FU_MUTE ?
1343 				" Switch" : " Volume");
1344 		break;
1345 	default:
1346 		if (!len)
1347 			strlcpy(kctl->id.name, audio_feature_info[control-1].name,
1348 				sizeof(kctl->id.name));
1349 		break;
1350 	}
1351 
1352 	/* get min/max values */
1353 	get_min_max_with_quirks(cval, 0, kctl);
1354 
1355 	if (control == UAC_FU_VOLUME) {
1356 		check_mapped_dB(map, cval);
1357 		if (cval->dBmin < cval->dBmax || !cval->initialized) {
1358 			kctl->tlv.c = snd_usb_mixer_vol_tlv;
1359 			kctl->vd[0].access |=
1360 				SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1361 				SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1362 		}
1363 	}
1364 
1365 	snd_usb_mixer_fu_apply_quirk(state->mixer, cval, unitid, kctl);
1366 
1367 	range = (cval->max - cval->min) / cval->res;
1368 	/*
1369 	 * Are there devices with volume range more than 255? I use a bit more
1370 	 * to be sure. 384 is a resolution magic number found on Logitech
1371 	 * devices. It will definitively catch all buggy Logitech devices.
1372 	 */
1373 	if (range > 384) {
1374 		usb_audio_warn(state->chip,
1375 			       "Warning! Unlikely big volume range (=%u), cval->res is probably wrong.",
1376 			       range);
1377 		usb_audio_warn(state->chip,
1378 			       "[%d] FU [%s] ch = %d, val = %d/%d/%d",
1379 			       cval->head.id, kctl->id.name, cval->channels,
1380 			       cval->min, cval->max, cval->res);
1381 	}
1382 
1383 	usb_audio_dbg(state->chip, "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
1384 		      cval->head.id, kctl->id.name, cval->channels,
1385 		      cval->min, cval->max, cval->res);
1386 	snd_usb_mixer_add_control(&cval->head, kctl);
1387 }
1388 
1389 static int parse_clock_source_unit(struct mixer_build *state, int unitid,
1390 				   void *_ftr)
1391 {
1392 	struct uac_clock_source_descriptor *hdr = _ftr;
1393 	struct usb_mixer_elem_info *cval;
1394 	struct snd_kcontrol *kctl;
1395 	char name[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
1396 	int ret;
1397 
1398 	if (state->mixer->protocol != UAC_VERSION_2)
1399 		return -EINVAL;
1400 
1401 	if (hdr->bLength != sizeof(*hdr)) {
1402 		usb_audio_dbg(state->chip,
1403 			      "Bogus clock source descriptor length of %d, ignoring.\n",
1404 			      hdr->bLength);
1405 		return 0;
1406 	}
1407 
1408 	/*
1409 	 * The only property of this unit we are interested in is the
1410 	 * clock source validity. If that isn't readable, just bail out.
1411 	 */
1412 	if (!uac2_control_is_readable(hdr->bmControls,
1413 				      ilog2(UAC2_CS_CONTROL_CLOCK_VALID)))
1414 		return 0;
1415 
1416 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1417 	if (!cval)
1418 		return -ENOMEM;
1419 
1420 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, hdr->bClockID);
1421 
1422 	cval->min = 0;
1423 	cval->max = 1;
1424 	cval->channels = 1;
1425 	cval->val_type = USB_MIXER_BOOLEAN;
1426 	cval->control = UAC2_CS_CONTROL_CLOCK_VALID;
1427 
1428 	if (uac2_control_is_writeable(hdr->bmControls,
1429 				      ilog2(UAC2_CS_CONTROL_CLOCK_VALID)))
1430 		kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1431 	else {
1432 		cval->master_readonly = 1;
1433 		kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
1434 	}
1435 
1436 	if (!kctl) {
1437 		kfree(cval);
1438 		return -ENOMEM;
1439 	}
1440 
1441 	kctl->private_free = snd_usb_mixer_elem_free;
1442 	ret = snd_usb_copy_string_desc(state, hdr->iClockSource,
1443 				       name, sizeof(name));
1444 	if (ret > 0)
1445 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1446 			 "%s Validity", name);
1447 	else
1448 		snprintf(kctl->id.name, sizeof(kctl->id.name),
1449 			 "Clock Source %d Validity", hdr->bClockID);
1450 
1451 	return snd_usb_mixer_add_control(&cval->head, kctl);
1452 }
1453 
1454 /*
1455  * parse a feature unit
1456  *
1457  * most of controls are defined here.
1458  */
1459 static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
1460 				    void *_ftr)
1461 {
1462 	int channels, i, j;
1463 	struct usb_audio_term iterm;
1464 	unsigned int master_bits, first_ch_bits;
1465 	int err, csize;
1466 	struct uac_feature_unit_descriptor *hdr = _ftr;
1467 	__u8 *bmaControls;
1468 
1469 	if (state->mixer->protocol == UAC_VERSION_1) {
1470 		csize = hdr->bControlSize;
1471 		if (!csize) {
1472 			usb_audio_dbg(state->chip,
1473 				      "unit %u: invalid bControlSize == 0\n",
1474 				      unitid);
1475 			return -EINVAL;
1476 		}
1477 		channels = (hdr->bLength - 7) / csize - 1;
1478 		bmaControls = hdr->bmaControls;
1479 		if (hdr->bLength < 7 + csize) {
1480 			usb_audio_err(state->chip,
1481 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1482 				      unitid);
1483 			return -EINVAL;
1484 		}
1485 	} else {
1486 		struct uac2_feature_unit_descriptor *ftr = _ftr;
1487 		csize = 4;
1488 		channels = (hdr->bLength - 6) / 4 - 1;
1489 		bmaControls = ftr->bmaControls;
1490 		if (hdr->bLength < 6 + csize) {
1491 			usb_audio_err(state->chip,
1492 				      "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1493 				      unitid);
1494 			return -EINVAL;
1495 		}
1496 	}
1497 
1498 	/* parse the source unit */
1499 	if ((err = parse_audio_unit(state, hdr->bSourceID)) < 0)
1500 		return err;
1501 
1502 	/* determine the input source type and name */
1503 	err = check_input_term(state, hdr->bSourceID, &iterm);
1504 	if (err < 0)
1505 		return err;
1506 
1507 	master_bits = snd_usb_combine_bytes(bmaControls, csize);
1508 	/* master configuration quirks */
1509 	switch (state->chip->usb_id) {
1510 	case USB_ID(0x08bb, 0x2702):
1511 		usb_audio_info(state->chip,
1512 			       "usbmixer: master volume quirk for PCM2702 chip\n");
1513 		/* disable non-functional volume control */
1514 		master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
1515 		break;
1516 	case USB_ID(0x1130, 0xf211):
1517 		usb_audio_info(state->chip,
1518 			       "usbmixer: volume control quirk for Tenx TP6911 Audio Headset\n");
1519 		/* disable non-functional volume control */
1520 		channels = 0;
1521 		break;
1522 
1523 	}
1524 	if (channels > 0)
1525 		first_ch_bits = snd_usb_combine_bytes(bmaControls + csize, csize);
1526 	else
1527 		first_ch_bits = 0;
1528 
1529 	if (state->mixer->protocol == UAC_VERSION_1) {
1530 		/* check all control types */
1531 		for (i = 0; i < 10; i++) {
1532 			unsigned int ch_bits = 0;
1533 			for (j = 0; j < channels; j++) {
1534 				unsigned int mask;
1535 
1536 				mask = snd_usb_combine_bytes(bmaControls +
1537 							     csize * (j+1), csize);
1538 				if (mask & (1 << i))
1539 					ch_bits |= (1 << j);
1540 			}
1541 			/* audio class v1 controls are never read-only */
1542 
1543 			/*
1544 			 * The first channel must be set
1545 			 * (for ease of programming).
1546 			 */
1547 			if (ch_bits & 1)
1548 				build_feature_ctl(state, _ftr, ch_bits, i,
1549 						  &iterm, unitid, 0);
1550 			if (master_bits & (1 << i))
1551 				build_feature_ctl(state, _ftr, 0, i, &iterm,
1552 						  unitid, 0);
1553 		}
1554 	} else { /* UAC_VERSION_2 */
1555 		for (i = 0; i < ARRAY_SIZE(audio_feature_info); i++) {
1556 			unsigned int ch_bits = 0;
1557 			unsigned int ch_read_only = 0;
1558 
1559 			for (j = 0; j < channels; j++) {
1560 				unsigned int mask;
1561 
1562 				mask = snd_usb_combine_bytes(bmaControls +
1563 							     csize * (j+1), csize);
1564 				if (uac2_control_is_readable(mask, i)) {
1565 					ch_bits |= (1 << j);
1566 					if (!uac2_control_is_writeable(mask, i))
1567 						ch_read_only |= (1 << j);
1568 				}
1569 			}
1570 
1571 			/*
1572 			 * NOTE: build_feature_ctl() will mark the control
1573 			 * read-only if all channels are marked read-only in
1574 			 * the descriptors. Otherwise, the control will be
1575 			 * reported as writeable, but the driver will not
1576 			 * actually issue a write command for read-only
1577 			 * channels.
1578 			 */
1579 
1580 			/*
1581 			 * The first channel must be set
1582 			 * (for ease of programming).
1583 			 */
1584 			if (ch_bits & 1)
1585 				build_feature_ctl(state, _ftr, ch_bits, i,
1586 						  &iterm, unitid, ch_read_only);
1587 			if (uac2_control_is_readable(master_bits, i))
1588 				build_feature_ctl(state, _ftr, 0, i, &iterm, unitid,
1589 						  !uac2_control_is_writeable(master_bits, i));
1590 		}
1591 	}
1592 
1593 	return 0;
1594 }
1595 
1596 /*
1597  * Mixer Unit
1598  */
1599 
1600 /*
1601  * build a mixer unit control
1602  *
1603  * the callbacks are identical with feature unit.
1604  * input channel number (zero based) is given in control field instead.
1605  */
1606 static void build_mixer_unit_ctl(struct mixer_build *state,
1607 				 struct uac_mixer_unit_descriptor *desc,
1608 				 int in_pin, int in_ch, int unitid,
1609 				 struct usb_audio_term *iterm)
1610 {
1611 	struct usb_mixer_elem_info *cval;
1612 	unsigned int num_outs = uac_mixer_unit_bNrChannels(desc);
1613 	unsigned int i, len;
1614 	struct snd_kcontrol *kctl;
1615 	const struct usbmix_name_map *map;
1616 
1617 	map = find_map(state, unitid, 0);
1618 	if (check_ignored_ctl(map))
1619 		return;
1620 
1621 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1622 	if (!cval)
1623 		return;
1624 
1625 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
1626 	cval->control = in_ch + 1; /* based on 1 */
1627 	cval->val_type = USB_MIXER_S16;
1628 	for (i = 0; i < num_outs; i++) {
1629 		__u8 *c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
1630 
1631 		if (check_matrix_bitmap(c, in_ch, i, num_outs)) {
1632 			cval->cmask |= (1 << i);
1633 			cval->channels++;
1634 		}
1635 	}
1636 
1637 	/* get min/max values */
1638 	get_min_max(cval, 0);
1639 
1640 	kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1641 	if (!kctl) {
1642 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
1643 		kfree(cval);
1644 		return;
1645 	}
1646 	kctl->private_free = snd_usb_mixer_elem_free;
1647 
1648 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1649 	if (!len)
1650 		len = get_term_name(state, iterm, kctl->id.name,
1651 				    sizeof(kctl->id.name), 0);
1652 	if (!len)
1653 		len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
1654 	append_ctl_name(kctl, " Volume");
1655 
1656 	usb_audio_dbg(state->chip, "[%d] MU [%s] ch = %d, val = %d/%d\n",
1657 		    cval->head.id, kctl->id.name, cval->channels, cval->min, cval->max);
1658 	snd_usb_mixer_add_control(&cval->head, kctl);
1659 }
1660 
1661 /*
1662  * parse a mixer unit
1663  */
1664 static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
1665 				  void *raw_desc)
1666 {
1667 	struct uac_mixer_unit_descriptor *desc = raw_desc;
1668 	struct usb_audio_term iterm;
1669 	int input_pins, num_ins, num_outs;
1670 	int pin, ich, err;
1671 
1672 	if (desc->bLength < 11 || !(input_pins = desc->bNrInPins) ||
1673 	    !(num_outs = uac_mixer_unit_bNrChannels(desc))) {
1674 		usb_audio_err(state->chip,
1675 			      "invalid MIXER UNIT descriptor %d\n",
1676 			      unitid);
1677 		return -EINVAL;
1678 	}
1679 
1680 	num_ins = 0;
1681 	ich = 0;
1682 	for (pin = 0; pin < input_pins; pin++) {
1683 		err = parse_audio_unit(state, desc->baSourceID[pin]);
1684 		if (err < 0)
1685 			continue;
1686 		/* no bmControls field (e.g. Maya44) -> ignore */
1687 		if (desc->bLength <= 10 + input_pins)
1688 			continue;
1689 		err = check_input_term(state, desc->baSourceID[pin], &iterm);
1690 		if (err < 0)
1691 			return err;
1692 		num_ins += iterm.channels;
1693 		for (; ich < num_ins; ich++) {
1694 			int och, ich_has_controls = 0;
1695 
1696 			for (och = 0; och < num_outs; och++) {
1697 				__u8 *c = uac_mixer_unit_bmControls(desc,
1698 						state->mixer->protocol);
1699 
1700 				if (check_matrix_bitmap(c, ich, och, num_outs)) {
1701 					ich_has_controls = 1;
1702 					break;
1703 				}
1704 			}
1705 			if (ich_has_controls)
1706 				build_mixer_unit_ctl(state, desc, pin, ich,
1707 						     unitid, &iterm);
1708 		}
1709 	}
1710 	return 0;
1711 }
1712 
1713 /*
1714  * Processing Unit / Extension Unit
1715  */
1716 
1717 /* get callback for processing/extension unit */
1718 static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol,
1719 				  struct snd_ctl_elem_value *ucontrol)
1720 {
1721 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1722 	int err, val;
1723 
1724 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
1725 	if (err < 0) {
1726 		ucontrol->value.integer.value[0] = cval->min;
1727 		return filter_error(cval, err);
1728 	}
1729 	val = get_relative_value(cval, val);
1730 	ucontrol->value.integer.value[0] = val;
1731 	return 0;
1732 }
1733 
1734 /* put callback for processing/extension unit */
1735 static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol,
1736 				  struct snd_ctl_elem_value *ucontrol)
1737 {
1738 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1739 	int val, oval, err;
1740 
1741 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
1742 	if (err < 0)
1743 		return filter_error(cval, err);
1744 	val = ucontrol->value.integer.value[0];
1745 	val = get_abs_value(cval, val);
1746 	if (val != oval) {
1747 		set_cur_ctl_value(cval, cval->control << 8, val);
1748 		return 1;
1749 	}
1750 	return 0;
1751 }
1752 
1753 /* alsa control interface for processing/extension unit */
1754 static const struct snd_kcontrol_new mixer_procunit_ctl = {
1755 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1756 	.name = "", /* will be filled later */
1757 	.info = mixer_ctl_feature_info,
1758 	.get = mixer_ctl_procunit_get,
1759 	.put = mixer_ctl_procunit_put,
1760 };
1761 
1762 /*
1763  * predefined data for processing units
1764  */
1765 struct procunit_value_info {
1766 	int control;
1767 	char *suffix;
1768 	int val_type;
1769 	int min_value;
1770 };
1771 
1772 struct procunit_info {
1773 	int type;
1774 	char *name;
1775 	struct procunit_value_info *values;
1776 };
1777 
1778 static struct procunit_value_info updown_proc_info[] = {
1779 	{ UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1780 	{ UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
1781 	{ 0 }
1782 };
1783 static struct procunit_value_info prologic_proc_info[] = {
1784 	{ UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1785 	{ UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
1786 	{ 0 }
1787 };
1788 static struct procunit_value_info threed_enh_proc_info[] = {
1789 	{ UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1790 	{ UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
1791 	{ 0 }
1792 };
1793 static struct procunit_value_info reverb_proc_info[] = {
1794 	{ UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1795 	{ UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
1796 	{ UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
1797 	{ UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
1798 	{ 0 }
1799 };
1800 static struct procunit_value_info chorus_proc_info[] = {
1801 	{ UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1802 	{ UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
1803 	{ UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
1804 	{ UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
1805 	{ 0 }
1806 };
1807 static struct procunit_value_info dcr_proc_info[] = {
1808 	{ UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1809 	{ UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
1810 	{ UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
1811 	{ UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
1812 	{ UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
1813 	{ UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
1814 	{ 0 }
1815 };
1816 
1817 static struct procunit_info procunits[] = {
1818 	{ UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
1819 	{ UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
1820 	{ UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
1821 	{ UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
1822 	{ UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
1823 	{ UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
1824 	{ 0 },
1825 };
1826 /*
1827  * predefined data for extension units
1828  */
1829 static struct procunit_value_info clock_rate_xu_info[] = {
1830 	{ USB_XU_CLOCK_RATE_SELECTOR, "Selector", USB_MIXER_U8, 0 },
1831 	{ 0 }
1832 };
1833 static struct procunit_value_info clock_source_xu_info[] = {
1834 	{ USB_XU_CLOCK_SOURCE_SELECTOR, "External", USB_MIXER_BOOLEAN },
1835 	{ 0 }
1836 };
1837 static struct procunit_value_info spdif_format_xu_info[] = {
1838 	{ USB_XU_DIGITAL_FORMAT_SELECTOR, "SPDIF/AC3", USB_MIXER_BOOLEAN },
1839 	{ 0 }
1840 };
1841 static struct procunit_value_info soft_limit_xu_info[] = {
1842 	{ USB_XU_SOFT_LIMIT_SELECTOR, " ", USB_MIXER_BOOLEAN },
1843 	{ 0 }
1844 };
1845 static struct procunit_info extunits[] = {
1846 	{ USB_XU_CLOCK_RATE, "Clock rate", clock_rate_xu_info },
1847 	{ USB_XU_CLOCK_SOURCE, "DigitalIn CLK source", clock_source_xu_info },
1848 	{ USB_XU_DIGITAL_IO_STATUS, "DigitalOut format:", spdif_format_xu_info },
1849 	{ USB_XU_DEVICE_OPTIONS, "AnalogueIn Soft Limit", soft_limit_xu_info },
1850 	{ 0 }
1851 };
1852 
1853 /*
1854  * build a processing/extension unit
1855  */
1856 static int build_audio_procunit(struct mixer_build *state, int unitid,
1857 				void *raw_desc, struct procunit_info *list,
1858 				char *name)
1859 {
1860 	struct uac_processing_unit_descriptor *desc = raw_desc;
1861 	int num_ins = desc->bNrInPins;
1862 	struct usb_mixer_elem_info *cval;
1863 	struct snd_kcontrol *kctl;
1864 	int i, err, nameid, type, len;
1865 	struct procunit_info *info;
1866 	struct procunit_value_info *valinfo;
1867 	const struct usbmix_name_map *map;
1868 	static struct procunit_value_info default_value_info[] = {
1869 		{ 0x01, "Switch", USB_MIXER_BOOLEAN },
1870 		{ 0 }
1871 	};
1872 	static struct procunit_info default_info = {
1873 		0, NULL, default_value_info
1874 	};
1875 
1876 	if (desc->bLength < 13 || desc->bLength < 13 + num_ins ||
1877 	    desc->bLength < num_ins + uac_processing_unit_bControlSize(desc, state->mixer->protocol)) {
1878 		usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid);
1879 		return -EINVAL;
1880 	}
1881 
1882 	for (i = 0; i < num_ins; i++) {
1883 		if ((err = parse_audio_unit(state, desc->baSourceID[i])) < 0)
1884 			return err;
1885 	}
1886 
1887 	type = le16_to_cpu(desc->wProcessType);
1888 	for (info = list; info && info->type; info++)
1889 		if (info->type == type)
1890 			break;
1891 	if (!info || !info->type)
1892 		info = &default_info;
1893 
1894 	for (valinfo = info->values; valinfo->control; valinfo++) {
1895 		__u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);
1896 
1897 		if (!(controls[valinfo->control / 8] & (1 << ((valinfo->control % 8) - 1))))
1898 			continue;
1899 		map = find_map(state, unitid, valinfo->control);
1900 		if (check_ignored_ctl(map))
1901 			continue;
1902 		cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1903 		if (!cval)
1904 			return -ENOMEM;
1905 		snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
1906 		cval->control = valinfo->control;
1907 		cval->val_type = valinfo->val_type;
1908 		cval->channels = 1;
1909 
1910 		/* get min/max values */
1911 		if (type == UAC_PROCESS_UP_DOWNMIX && cval->control == UAC_UD_MODE_SELECT) {
1912 			__u8 *control_spec = uac_processing_unit_specific(desc, state->mixer->protocol);
1913 			/* FIXME: hard-coded */
1914 			cval->min = 1;
1915 			cval->max = control_spec[0];
1916 			cval->res = 1;
1917 			cval->initialized = 1;
1918 		} else {
1919 			if (type == USB_XU_CLOCK_RATE) {
1920 				/*
1921 				 * E-Mu USB 0404/0202/TrackerPre/0204
1922 				 * samplerate control quirk
1923 				 */
1924 				cval->min = 0;
1925 				cval->max = 5;
1926 				cval->res = 1;
1927 				cval->initialized = 1;
1928 			} else
1929 				get_min_max(cval, valinfo->min_value);
1930 		}
1931 
1932 		kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
1933 		if (!kctl) {
1934 			kfree(cval);
1935 			return -ENOMEM;
1936 		}
1937 		kctl->private_free = snd_usb_mixer_elem_free;
1938 
1939 		if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name))) {
1940 			/* nothing */ ;
1941 		} else if (info->name) {
1942 			strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
1943 		} else {
1944 			nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
1945 			len = 0;
1946 			if (nameid)
1947 				len = snd_usb_copy_string_desc(state, nameid,
1948 							       kctl->id.name,
1949 							       sizeof(kctl->id.name));
1950 			if (!len)
1951 				strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
1952 		}
1953 		append_ctl_name(kctl, " ");
1954 		append_ctl_name(kctl, valinfo->suffix);
1955 
1956 		usb_audio_dbg(state->chip,
1957 			      "[%d] PU [%s] ch = %d, val = %d/%d\n",
1958 			      cval->head.id, kctl->id.name, cval->channels,
1959 			      cval->min, cval->max);
1960 
1961 		err = snd_usb_mixer_add_control(&cval->head, kctl);
1962 		if (err < 0)
1963 			return err;
1964 	}
1965 	return 0;
1966 }
1967 
1968 static int parse_audio_processing_unit(struct mixer_build *state, int unitid,
1969 				       void *raw_desc)
1970 {
1971 	return build_audio_procunit(state, unitid, raw_desc,
1972 				    procunits, "Processing Unit");
1973 }
1974 
1975 static int parse_audio_extension_unit(struct mixer_build *state, int unitid,
1976 				      void *raw_desc)
1977 {
1978 	/*
1979 	 * Note that we parse extension units with processing unit descriptors.
1980 	 * That's ok as the layout is the same.
1981 	 */
1982 	return build_audio_procunit(state, unitid, raw_desc,
1983 				    extunits, "Extension Unit");
1984 }
1985 
1986 /*
1987  * Selector Unit
1988  */
1989 
1990 /*
1991  * info callback for selector unit
1992  * use an enumerator type for routing
1993  */
1994 static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol,
1995 				   struct snd_ctl_elem_info *uinfo)
1996 {
1997 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
1998 	const char **itemlist = (const char **)kcontrol->private_value;
1999 
2000 	if (snd_BUG_ON(!itemlist))
2001 		return -EINVAL;
2002 	return snd_ctl_enum_info(uinfo, 1, cval->max, itemlist);
2003 }
2004 
2005 /* get callback for selector unit */
2006 static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol,
2007 				  struct snd_ctl_elem_value *ucontrol)
2008 {
2009 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2010 	int val, err;
2011 
2012 	err = get_cur_ctl_value(cval, cval->control << 8, &val);
2013 	if (err < 0) {
2014 		ucontrol->value.enumerated.item[0] = 0;
2015 		return filter_error(cval, err);
2016 	}
2017 	val = get_relative_value(cval, val);
2018 	ucontrol->value.enumerated.item[0] = val;
2019 	return 0;
2020 }
2021 
2022 /* put callback for selector unit */
2023 static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol,
2024 				  struct snd_ctl_elem_value *ucontrol)
2025 {
2026 	struct usb_mixer_elem_info *cval = kcontrol->private_data;
2027 	int val, oval, err;
2028 
2029 	err = get_cur_ctl_value(cval, cval->control << 8, &oval);
2030 	if (err < 0)
2031 		return filter_error(cval, err);
2032 	val = ucontrol->value.enumerated.item[0];
2033 	val = get_abs_value(cval, val);
2034 	if (val != oval) {
2035 		set_cur_ctl_value(cval, cval->control << 8, val);
2036 		return 1;
2037 	}
2038 	return 0;
2039 }
2040 
2041 /* alsa control interface for selector unit */
2042 static const struct snd_kcontrol_new mixer_selectunit_ctl = {
2043 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
2044 	.name = "", /* will be filled later */
2045 	.info = mixer_ctl_selector_info,
2046 	.get = mixer_ctl_selector_get,
2047 	.put = mixer_ctl_selector_put,
2048 };
2049 
2050 /*
2051  * private free callback.
2052  * free both private_data and private_value
2053  */
2054 static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
2055 {
2056 	int i, num_ins = 0;
2057 
2058 	if (kctl->private_data) {
2059 		struct usb_mixer_elem_info *cval = kctl->private_data;
2060 		num_ins = cval->max;
2061 		kfree(cval);
2062 		kctl->private_data = NULL;
2063 	}
2064 	if (kctl->private_value) {
2065 		char **itemlist = (char **)kctl->private_value;
2066 		for (i = 0; i < num_ins; i++)
2067 			kfree(itemlist[i]);
2068 		kfree(itemlist);
2069 		kctl->private_value = 0;
2070 	}
2071 }
2072 
2073 /*
2074  * parse a selector unit
2075  */
2076 static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
2077 				     void *raw_desc)
2078 {
2079 	struct uac_selector_unit_descriptor *desc = raw_desc;
2080 	unsigned int i, nameid, len;
2081 	int err;
2082 	struct usb_mixer_elem_info *cval;
2083 	struct snd_kcontrol *kctl;
2084 	const struct usbmix_name_map *map;
2085 	char **namelist;
2086 
2087 	if (!desc->bNrInPins || desc->bLength < 5 + desc->bNrInPins) {
2088 		usb_audio_err(state->chip,
2089 			"invalid SELECTOR UNIT descriptor %d\n", unitid);
2090 		return -EINVAL;
2091 	}
2092 
2093 	for (i = 0; i < desc->bNrInPins; i++) {
2094 		if ((err = parse_audio_unit(state, desc->baSourceID[i])) < 0)
2095 			return err;
2096 	}
2097 
2098 	if (desc->bNrInPins == 1) /* only one ? nonsense! */
2099 		return 0;
2100 
2101 	map = find_map(state, unitid, 0);
2102 	if (check_ignored_ctl(map))
2103 		return 0;
2104 
2105 	cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2106 	if (!cval)
2107 		return -ENOMEM;
2108 	snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2109 	cval->val_type = USB_MIXER_U8;
2110 	cval->channels = 1;
2111 	cval->min = 1;
2112 	cval->max = desc->bNrInPins;
2113 	cval->res = 1;
2114 	cval->initialized = 1;
2115 
2116 	if (state->mixer->protocol == UAC_VERSION_1)
2117 		cval->control = 0;
2118 	else /* UAC_VERSION_2 */
2119 		cval->control = (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR) ?
2120 			UAC2_CX_CLOCK_SELECTOR : UAC2_SU_SELECTOR;
2121 
2122 	namelist = kmalloc(sizeof(char *) * desc->bNrInPins, GFP_KERNEL);
2123 	if (!namelist) {
2124 		kfree(cval);
2125 		return -ENOMEM;
2126 	}
2127 #define MAX_ITEM_NAME_LEN	64
2128 	for (i = 0; i < desc->bNrInPins; i++) {
2129 		struct usb_audio_term iterm;
2130 		len = 0;
2131 		namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
2132 		if (!namelist[i]) {
2133 			while (i--)
2134 				kfree(namelist[i]);
2135 			kfree(namelist);
2136 			kfree(cval);
2137 			return -ENOMEM;
2138 		}
2139 		len = check_mapped_selector_name(state, unitid, i, namelist[i],
2140 						 MAX_ITEM_NAME_LEN);
2141 		if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
2142 			len = get_term_name(state, &iterm, namelist[i], MAX_ITEM_NAME_LEN, 0);
2143 		if (! len)
2144 			sprintf(namelist[i], "Input %u", i);
2145 	}
2146 
2147 	kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
2148 	if (! kctl) {
2149 		usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2150 		kfree(namelist);
2151 		kfree(cval);
2152 		return -ENOMEM;
2153 	}
2154 	kctl->private_value = (unsigned long)namelist;
2155 	kctl->private_free = usb_mixer_selector_elem_free;
2156 
2157 	nameid = uac_selector_unit_iSelector(desc);
2158 	len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2159 	if (len)
2160 		;
2161 	else if (nameid)
2162 		snd_usb_copy_string_desc(state, nameid, kctl->id.name,
2163 					 sizeof(kctl->id.name));
2164 	else {
2165 		len = get_term_name(state, &state->oterm,
2166 				    kctl->id.name, sizeof(kctl->id.name), 0);
2167 		if (!len)
2168 			strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
2169 
2170 		if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR)
2171 			append_ctl_name(kctl, " Clock Source");
2172 		else if ((state->oterm.type & 0xff00) == 0x0100)
2173 			append_ctl_name(kctl, " Capture Source");
2174 		else
2175 			append_ctl_name(kctl, " Playback Source");
2176 	}
2177 
2178 	usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
2179 		    cval->head.id, kctl->id.name, desc->bNrInPins);
2180 	return snd_usb_mixer_add_control(&cval->head, kctl);
2181 }
2182 
2183 /*
2184  * parse an audio unit recursively
2185  */
2186 
2187 static int parse_audio_unit(struct mixer_build *state, int unitid)
2188 {
2189 	unsigned char *p1;
2190 
2191 	if (test_and_set_bit(unitid, state->unitbitmap))
2192 		return 0; /* the unit already visited */
2193 
2194 	p1 = find_audio_control_unit(state, unitid);
2195 	if (!p1) {
2196 		usb_audio_err(state->chip, "unit %d not found!\n", unitid);
2197 		return -EINVAL;
2198 	}
2199 
2200 	switch (p1[2]) {
2201 	case UAC_INPUT_TERMINAL:
2202 		return 0; /* NOP */
2203 	case UAC_MIXER_UNIT:
2204 		return parse_audio_mixer_unit(state, unitid, p1);
2205 	case UAC2_CLOCK_SOURCE:
2206 		return parse_clock_source_unit(state, unitid, p1);
2207 	case UAC_SELECTOR_UNIT:
2208 	case UAC2_CLOCK_SELECTOR:
2209 		return parse_audio_selector_unit(state, unitid, p1);
2210 	case UAC_FEATURE_UNIT:
2211 		return parse_audio_feature_unit(state, unitid, p1);
2212 	case UAC1_PROCESSING_UNIT:
2213 	/*   UAC2_EFFECT_UNIT has the same value */
2214 		if (state->mixer->protocol == UAC_VERSION_1)
2215 			return parse_audio_processing_unit(state, unitid, p1);
2216 		else
2217 			return 0; /* FIXME - effect units not implemented yet */
2218 	case UAC1_EXTENSION_UNIT:
2219 	/*   UAC2_PROCESSING_UNIT_V2 has the same value */
2220 		if (state->mixer->protocol == UAC_VERSION_1)
2221 			return parse_audio_extension_unit(state, unitid, p1);
2222 		else /* UAC_VERSION_2 */
2223 			return parse_audio_processing_unit(state, unitid, p1);
2224 	case UAC2_EXTENSION_UNIT_V2:
2225 		return parse_audio_extension_unit(state, unitid, p1);
2226 	default:
2227 		usb_audio_err(state->chip,
2228 			"unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
2229 		return -EINVAL;
2230 	}
2231 }
2232 
2233 static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
2234 {
2235 	kfree(mixer->id_elems);
2236 	if (mixer->urb) {
2237 		kfree(mixer->urb->transfer_buffer);
2238 		usb_free_urb(mixer->urb);
2239 	}
2240 	usb_free_urb(mixer->rc_urb);
2241 	kfree(mixer->rc_setup_packet);
2242 	kfree(mixer);
2243 }
2244 
2245 static int snd_usb_mixer_dev_free(struct snd_device *device)
2246 {
2247 	struct usb_mixer_interface *mixer = device->device_data;
2248 	snd_usb_mixer_free(mixer);
2249 	return 0;
2250 }
2251 
2252 /*
2253  * create mixer controls
2254  *
2255  * walk through all UAC_OUTPUT_TERMINAL descriptors to search for mixers
2256  */
2257 static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
2258 {
2259 	struct mixer_build state;
2260 	int err;
2261 	const struct usbmix_ctl_map *map;
2262 	void *p;
2263 
2264 	memset(&state, 0, sizeof(state));
2265 	state.chip = mixer->chip;
2266 	state.mixer = mixer;
2267 	state.buffer = mixer->hostif->extra;
2268 	state.buflen = mixer->hostif->extralen;
2269 
2270 	/* check the mapping table */
2271 	for (map = usbmix_ctl_maps; map->id; map++) {
2272 		if (map->id == state.chip->usb_id) {
2273 			state.map = map->map;
2274 			state.selector_map = map->selector_map;
2275 			mixer->ignore_ctl_error = map->ignore_ctl_error;
2276 			break;
2277 		}
2278 	}
2279 
2280 	p = NULL;
2281 	while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
2282 					    mixer->hostif->extralen,
2283 					    p, UAC_OUTPUT_TERMINAL)) != NULL) {
2284 		if (mixer->protocol == UAC_VERSION_1) {
2285 			struct uac1_output_terminal_descriptor *desc = p;
2286 
2287 			if (desc->bLength < sizeof(*desc))
2288 				continue; /* invalid descriptor? */
2289 			/* mark terminal ID as visited */
2290 			set_bit(desc->bTerminalID, state.unitbitmap);
2291 			state.oterm.id = desc->bTerminalID;
2292 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
2293 			state.oterm.name = desc->iTerminal;
2294 			err = parse_audio_unit(&state, desc->bSourceID);
2295 			if (err < 0 && err != -EINVAL)
2296 				return err;
2297 		} else { /* UAC_VERSION_2 */
2298 			struct uac2_output_terminal_descriptor *desc = p;
2299 
2300 			if (desc->bLength < sizeof(*desc))
2301 				continue; /* invalid descriptor? */
2302 			/* mark terminal ID as visited */
2303 			set_bit(desc->bTerminalID, state.unitbitmap);
2304 			state.oterm.id = desc->bTerminalID;
2305 			state.oterm.type = le16_to_cpu(desc->wTerminalType);
2306 			state.oterm.name = desc->iTerminal;
2307 			err = parse_audio_unit(&state, desc->bSourceID);
2308 			if (err < 0 && err != -EINVAL)
2309 				return err;
2310 
2311 			/*
2312 			 * For UAC2, use the same approach to also add the
2313 			 * clock selectors
2314 			 */
2315 			err = parse_audio_unit(&state, desc->bCSourceID);
2316 			if (err < 0 && err != -EINVAL)
2317 				return err;
2318 		}
2319 	}
2320 
2321 	return 0;
2322 }
2323 
2324 void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
2325 {
2326 	struct usb_mixer_elem_list *list;
2327 
2328 	for (list = mixer->id_elems[unitid]; list; list = list->next_id_elem)
2329 		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
2330 			       &list->kctl->id);
2331 }
2332 
2333 static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
2334 				    struct usb_mixer_elem_list *list)
2335 {
2336 	struct usb_mixer_elem_info *cval = (struct usb_mixer_elem_info *)list;
2337 	static char *val_types[] = {"BOOLEAN", "INV_BOOLEAN",
2338 				    "S8", "U8", "S16", "U16"};
2339 	snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
2340 			    "channels=%i, type=\"%s\"\n", cval->head.id,
2341 			    cval->control, cval->cmask, cval->channels,
2342 			    val_types[cval->val_type]);
2343 	snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
2344 			    cval->min, cval->max, cval->dBmin, cval->dBmax);
2345 }
2346 
2347 static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
2348 				    struct snd_info_buffer *buffer)
2349 {
2350 	struct snd_usb_audio *chip = entry->private_data;
2351 	struct usb_mixer_interface *mixer;
2352 	struct usb_mixer_elem_list *list;
2353 	int unitid;
2354 
2355 	list_for_each_entry(mixer, &chip->mixer_list, list) {
2356 		snd_iprintf(buffer,
2357 			"USB Mixer: usb_id=0x%08x, ctrlif=%i, ctlerr=%i\n",
2358 				chip->usb_id, snd_usb_ctrl_intf(chip),
2359 				mixer->ignore_ctl_error);
2360 		snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
2361 		for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
2362 			for (list = mixer->id_elems[unitid]; list;
2363 			     list = list->next_id_elem) {
2364 				snd_iprintf(buffer, "  Unit: %i\n", list->id);
2365 				if (list->kctl)
2366 					snd_iprintf(buffer,
2367 						    "    Control: name=\"%s\", index=%i\n",
2368 						    list->kctl->id.name,
2369 						    list->kctl->id.index);
2370 				if (list->dump)
2371 					list->dump(buffer, list);
2372 			}
2373 		}
2374 	}
2375 }
2376 
2377 static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
2378 				       int attribute, int value, int index)
2379 {
2380 	struct usb_mixer_elem_list *list;
2381 	__u8 unitid = (index >> 8) & 0xff;
2382 	__u8 control = (value >> 8) & 0xff;
2383 	__u8 channel = value & 0xff;
2384 	unsigned int count = 0;
2385 
2386 	if (channel >= MAX_CHANNELS) {
2387 		usb_audio_dbg(mixer->chip,
2388 			"%s(): bogus channel number %d\n",
2389 			__func__, channel);
2390 		return;
2391 	}
2392 
2393 	for (list = mixer->id_elems[unitid]; list; list = list->next_id_elem)
2394 		count++;
2395 
2396 	if (count == 0)
2397 		return;
2398 
2399 	for (list = mixer->id_elems[unitid]; list; list = list->next_id_elem) {
2400 		struct usb_mixer_elem_info *info;
2401 
2402 		if (!list->kctl)
2403 			continue;
2404 
2405 		info = (struct usb_mixer_elem_info *)list;
2406 		if (count > 1 && info->control != control)
2407 			continue;
2408 
2409 		switch (attribute) {
2410 		case UAC2_CS_CUR:
2411 			/* invalidate cache, so the value is read from the device */
2412 			if (channel)
2413 				info->cached &= ~(1 << channel);
2414 			else /* master channel */
2415 				info->cached = 0;
2416 
2417 			snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
2418 				       &info->head.kctl->id);
2419 			break;
2420 
2421 		case UAC2_CS_RANGE:
2422 			/* TODO */
2423 			break;
2424 
2425 		case UAC2_CS_MEM:
2426 			/* TODO */
2427 			break;
2428 
2429 		default:
2430 			usb_audio_dbg(mixer->chip,
2431 				"unknown attribute %d in interrupt\n",
2432 				attribute);
2433 			break;
2434 		} /* switch */
2435 	}
2436 }
2437 
2438 static void snd_usb_mixer_interrupt(struct urb *urb)
2439 {
2440 	struct usb_mixer_interface *mixer = urb->context;
2441 	int len = urb->actual_length;
2442 	int ustatus = urb->status;
2443 
2444 	if (ustatus != 0)
2445 		goto requeue;
2446 
2447 	if (mixer->protocol == UAC_VERSION_1) {
2448 		struct uac1_status_word *status;
2449 
2450 		for (status = urb->transfer_buffer;
2451 		     len >= sizeof(*status);
2452 		     len -= sizeof(*status), status++) {
2453 			dev_dbg(&urb->dev->dev, "status interrupt: %02x %02x\n",
2454 						status->bStatusType,
2455 						status->bOriginator);
2456 
2457 			/* ignore any notifications not from the control interface */
2458 			if ((status->bStatusType & UAC1_STATUS_TYPE_ORIG_MASK) !=
2459 				UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF)
2460 				continue;
2461 
2462 			if (status->bStatusType & UAC1_STATUS_TYPE_MEM_CHANGED)
2463 				snd_usb_mixer_rc_memory_change(mixer, status->bOriginator);
2464 			else
2465 				snd_usb_mixer_notify_id(mixer, status->bOriginator);
2466 		}
2467 	} else { /* UAC_VERSION_2 */
2468 		struct uac2_interrupt_data_msg *msg;
2469 
2470 		for (msg = urb->transfer_buffer;
2471 		     len >= sizeof(*msg);
2472 		     len -= sizeof(*msg), msg++) {
2473 			/* drop vendor specific and endpoint requests */
2474 			if ((msg->bInfo & UAC2_INTERRUPT_DATA_MSG_VENDOR) ||
2475 			    (msg->bInfo & UAC2_INTERRUPT_DATA_MSG_EP))
2476 				continue;
2477 
2478 			snd_usb_mixer_interrupt_v2(mixer, msg->bAttribute,
2479 						   le16_to_cpu(msg->wValue),
2480 						   le16_to_cpu(msg->wIndex));
2481 		}
2482 	}
2483 
2484 requeue:
2485 	if (ustatus != -ENOENT &&
2486 	    ustatus != -ECONNRESET &&
2487 	    ustatus != -ESHUTDOWN) {
2488 		urb->dev = mixer->chip->dev;
2489 		usb_submit_urb(urb, GFP_ATOMIC);
2490 	}
2491 }
2492 
2493 /* create the handler for the optional status interrupt endpoint */
2494 static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
2495 {
2496 	struct usb_endpoint_descriptor *ep;
2497 	void *transfer_buffer;
2498 	int buffer_length;
2499 	unsigned int epnum;
2500 
2501 	/* we need one interrupt input endpoint */
2502 	if (get_iface_desc(mixer->hostif)->bNumEndpoints < 1)
2503 		return 0;
2504 	ep = get_endpoint(mixer->hostif, 0);
2505 	if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_int(ep))
2506 		return 0;
2507 
2508 	epnum = usb_endpoint_num(ep);
2509 	buffer_length = le16_to_cpu(ep->wMaxPacketSize);
2510 	transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
2511 	if (!transfer_buffer)
2512 		return -ENOMEM;
2513 	mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
2514 	if (!mixer->urb) {
2515 		kfree(transfer_buffer);
2516 		return -ENOMEM;
2517 	}
2518 	usb_fill_int_urb(mixer->urb, mixer->chip->dev,
2519 			 usb_rcvintpipe(mixer->chip->dev, epnum),
2520 			 transfer_buffer, buffer_length,
2521 			 snd_usb_mixer_interrupt, mixer, ep->bInterval);
2522 	usb_submit_urb(mixer->urb, GFP_KERNEL);
2523 	return 0;
2524 }
2525 
2526 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
2527 			 int ignore_error)
2528 {
2529 	static struct snd_device_ops dev_ops = {
2530 		.dev_free = snd_usb_mixer_dev_free
2531 	};
2532 	struct usb_mixer_interface *mixer;
2533 	struct snd_info_entry *entry;
2534 	int err;
2535 
2536 	strcpy(chip->card->mixername, "USB Mixer");
2537 
2538 	mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
2539 	if (!mixer)
2540 		return -ENOMEM;
2541 	mixer->chip = chip;
2542 	mixer->ignore_ctl_error = ignore_error;
2543 	mixer->id_elems = kcalloc(MAX_ID_ELEMS, sizeof(*mixer->id_elems),
2544 				  GFP_KERNEL);
2545 	if (!mixer->id_elems) {
2546 		kfree(mixer);
2547 		return -ENOMEM;
2548 	}
2549 
2550 	mixer->hostif = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
2551 	switch (get_iface_desc(mixer->hostif)->bInterfaceProtocol) {
2552 	case UAC_VERSION_1:
2553 	default:
2554 		mixer->protocol = UAC_VERSION_1;
2555 		break;
2556 	case UAC_VERSION_2:
2557 		mixer->protocol = UAC_VERSION_2;
2558 		break;
2559 	}
2560 
2561 	if ((err = snd_usb_mixer_controls(mixer)) < 0 ||
2562 	    (err = snd_usb_mixer_status_create(mixer)) < 0)
2563 		goto _error;
2564 
2565 	snd_usb_mixer_apply_create_quirk(mixer);
2566 
2567 	err = snd_device_new(chip->card, SNDRV_DEV_CODEC, mixer, &dev_ops);
2568 	if (err < 0)
2569 		goto _error;
2570 
2571 	if (list_empty(&chip->mixer_list) &&
2572 	    !snd_card_proc_new(chip->card, "usbmixer", &entry))
2573 		snd_info_set_text_ops(entry, chip, snd_usb_mixer_proc_read);
2574 
2575 	list_add(&mixer->list, &chip->mixer_list);
2576 	return 0;
2577 
2578 _error:
2579 	snd_usb_mixer_free(mixer);
2580 	return err;
2581 }
2582 
2583 void snd_usb_mixer_disconnect(struct usb_mixer_interface *mixer)
2584 {
2585 	usb_kill_urb(mixer->urb);
2586 	usb_kill_urb(mixer->rc_urb);
2587 }
2588 
2589 #ifdef CONFIG_PM
2590 /* stop any bus activity of a mixer */
2591 static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
2592 {
2593 	usb_kill_urb(mixer->urb);
2594 	usb_kill_urb(mixer->rc_urb);
2595 }
2596 
2597 static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
2598 {
2599 	int err;
2600 
2601 	if (mixer->urb) {
2602 		err = usb_submit_urb(mixer->urb, GFP_NOIO);
2603 		if (err < 0)
2604 			return err;
2605 	}
2606 
2607 	return 0;
2608 }
2609 
2610 int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
2611 {
2612 	snd_usb_mixer_inactivate(mixer);
2613 	return 0;
2614 }
2615 
2616 static int restore_mixer_value(struct usb_mixer_elem_list *list)
2617 {
2618 	struct usb_mixer_elem_info *cval = (struct usb_mixer_elem_info *)list;
2619 	int c, err, idx;
2620 
2621 	if (cval->cmask) {
2622 		idx = 0;
2623 		for (c = 0; c < MAX_CHANNELS; c++) {
2624 			if (!(cval->cmask & (1 << c)))
2625 				continue;
2626 			if (cval->cached & (1 << (c + 1))) {
2627 				err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
2628 							cval->cache_val[idx]);
2629 				if (err < 0)
2630 					return err;
2631 			}
2632 			idx++;
2633 		}
2634 	} else {
2635 		/* master */
2636 		if (cval->cached) {
2637 			err = snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
2638 			if (err < 0)
2639 				return err;
2640 		}
2641 	}
2642 
2643 	return 0;
2644 }
2645 
2646 int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume)
2647 {
2648 	struct usb_mixer_elem_list *list;
2649 	int id, err;
2650 
2651 	if (reset_resume) {
2652 		/* restore cached mixer values */
2653 		for (id = 0; id < MAX_ID_ELEMS; id++) {
2654 			for (list = mixer->id_elems[id]; list;
2655 			     list = list->next_id_elem) {
2656 				if (list->resume) {
2657 					err = list->resume(list);
2658 					if (err < 0)
2659 						return err;
2660 				}
2661 			}
2662 		}
2663 	}
2664 
2665 	return snd_usb_mixer_activate(mixer);
2666 }
2667 #endif
2668 
2669 void snd_usb_mixer_elem_init_std(struct usb_mixer_elem_list *list,
2670 				 struct usb_mixer_interface *mixer,
2671 				 int unitid)
2672 {
2673 	list->mixer = mixer;
2674 	list->id = unitid;
2675 	list->dump = snd_usb_mixer_dump_cval;
2676 #ifdef CONFIG_PM
2677 	list->resume = restore_mixer_value;
2678 #endif
2679 }
2680