Merge tag 'drm-intel-fixes-2015-06-05' of git://anongit.freedesktop.org/drm-intel...
[sfrench/cifs-2.6.git] / sound / usb / mixer.c
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/slab.h>
49 #include <linux/string.h>
50 #include <linux/usb.h>
51 #include <linux/usb/audio.h>
52 #include <linux/usb/audio-v2.h>
53
54 #include <sound/core.h>
55 #include <sound/control.h>
56 #include <sound/hwdep.h>
57 #include <sound/info.h>
58 #include <sound/tlv.h>
59
60 #include "usbaudio.h"
61 #include "mixer.h"
62 #include "helper.h"
63 #include "mixer_quirks.h"
64 #include "power.h"
65
66 #define MAX_ID_ELEMS    256
67
68 struct usb_audio_term {
69         int id;
70         int type;
71         int channels;
72         unsigned int chconfig;
73         int name;
74 };
75
76 struct usbmix_name_map;
77
78 struct mixer_build {
79         struct snd_usb_audio *chip;
80         struct usb_mixer_interface *mixer;
81         unsigned char *buffer;
82         unsigned int buflen;
83         DECLARE_BITMAP(unitbitmap, MAX_ID_ELEMS);
84         struct usb_audio_term oterm;
85         const struct usbmix_name_map *map;
86         const struct usbmix_selector_map *selector_map;
87 };
88
89 /*E-mu 0202/0404/0204 eXtension Unit(XU) control*/
90 enum {
91         USB_XU_CLOCK_RATE               = 0xe301,
92         USB_XU_CLOCK_SOURCE             = 0xe302,
93         USB_XU_DIGITAL_IO_STATUS        = 0xe303,
94         USB_XU_DEVICE_OPTIONS           = 0xe304,
95         USB_XU_DIRECT_MONITORING        = 0xe305,
96         USB_XU_METERING                 = 0xe306
97 };
98 enum {
99         USB_XU_CLOCK_SOURCE_SELECTOR = 0x02,    /* clock source*/
100         USB_XU_CLOCK_RATE_SELECTOR = 0x03,      /* clock rate */
101         USB_XU_DIGITAL_FORMAT_SELECTOR = 0x01,  /* the spdif format */
102         USB_XU_SOFT_LIMIT_SELECTOR = 0x03       /* soft limiter */
103 };
104
105 /*
106  * manual mapping of mixer names
107  * if the mixer topology is too complicated and the parsed names are
108  * ambiguous, add the entries in usbmixer_maps.c.
109  */
110 #include "mixer_maps.c"
111
112 static const struct usbmix_name_map *
113 find_map(struct mixer_build *state, int unitid, int control)
114 {
115         const struct usbmix_name_map *p = state->map;
116
117         if (!p)
118                 return NULL;
119
120         for (p = state->map; 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 <= UAC2_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 mixer_build *state,
203                                     int index, char *buf, int maxlen)
204 {
205         int len = usb_string(state->chip->dev, index, buf, maxlen - 1);
206         buf[len] = 0;
207         return len;
208 }
209
210 /*
211  * convert from the byte/word on usb descriptor to the zero-based integer
212  */
213 static int convert_signed_value(struct usb_mixer_elem_info *cval, int val)
214 {
215         switch (cval->val_type) {
216         case USB_MIXER_BOOLEAN:
217                 return !!val;
218         case USB_MIXER_INV_BOOLEAN:
219                 return !val;
220         case USB_MIXER_U8:
221                 val &= 0xff;
222                 break;
223         case USB_MIXER_S8:
224                 val &= 0xff;
225                 if (val >= 0x80)
226                         val -= 0x100;
227                 break;
228         case USB_MIXER_U16:
229                 val &= 0xffff;
230                 break;
231         case USB_MIXER_S16:
232                 val &= 0xffff;
233                 if (val >= 0x8000)
234                         val -= 0x10000;
235                 break;
236         }
237         return val;
238 }
239
240 /*
241  * convert from the zero-based int to the byte/word for usb descriptor
242  */
243 static int convert_bytes_value(struct usb_mixer_elem_info *cval, int val)
244 {
245         switch (cval->val_type) {
246         case USB_MIXER_BOOLEAN:
247                 return !!val;
248         case USB_MIXER_INV_BOOLEAN:
249                 return !val;
250         case USB_MIXER_S8:
251         case USB_MIXER_U8:
252                 return val & 0xff;
253         case USB_MIXER_S16:
254         case USB_MIXER_U16:
255                 return val & 0xffff;
256         }
257         return 0; /* not reached */
258 }
259
260 static int get_relative_value(struct usb_mixer_elem_info *cval, int val)
261 {
262         if (!cval->res)
263                 cval->res = 1;
264         if (val < cval->min)
265                 return 0;
266         else if (val >= cval->max)
267                 return (cval->max - cval->min + cval->res - 1) / cval->res;
268         else
269                 return (val - cval->min) / cval->res;
270 }
271
272 static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
273 {
274         if (val < 0)
275                 return cval->min;
276         if (!cval->res)
277                 cval->res = 1;
278         val *= cval->res;
279         val += cval->min;
280         if (val > cval->max)
281                 return cval->max;
282         return val;
283 }
284
285
286 /*
287  * retrieve a mixer value
288  */
289
290 static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request,
291                             int validx, int *value_ret)
292 {
293         struct snd_usb_audio *chip = cval->head.mixer->chip;
294         unsigned char buf[2];
295         int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
296         int timeout = 10;
297         int idx = 0, err;
298
299         err = snd_usb_autoresume(chip);
300         if (err < 0)
301                 return -EIO;
302
303         down_read(&chip->shutdown_rwsem);
304         while (timeout-- > 0) {
305                 if (chip->shutdown)
306                         break;
307                 idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
308                 if (snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), request,
309                                     USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
310                                     validx, idx, buf, val_len) >= val_len) {
311                         *value_ret = convert_signed_value(cval, snd_usb_combine_bytes(buf, val_len));
312                         err = 0;
313                         goto out;
314                 }
315         }
316         usb_audio_dbg(chip,
317                 "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
318                 request, validx, idx, cval->val_type);
319         err = -EINVAL;
320
321  out:
322         up_read(&chip->shutdown_rwsem);
323         snd_usb_autosuspend(chip);
324         return err;
325 }
326
327 static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request,
328                             int validx, int *value_ret)
329 {
330         struct snd_usb_audio *chip = cval->head.mixer->chip;
331         unsigned char buf[2 + 3 * sizeof(__u16)]; /* enough space for one range */
332         unsigned char *val;
333         int idx = 0, ret, size;
334         __u8 bRequest;
335
336         if (request == UAC_GET_CUR) {
337                 bRequest = UAC2_CS_CUR;
338                 size = sizeof(__u16);
339         } else {
340                 bRequest = UAC2_CS_RANGE;
341                 size = sizeof(buf);
342         }
343
344         memset(buf, 0, sizeof(buf));
345
346         ret = snd_usb_autoresume(chip) ? -EIO : 0;
347         if (ret)
348                 goto error;
349
350         down_read(&chip->shutdown_rwsem);
351         if (chip->shutdown) {
352                 ret = -ENODEV;
353         } else {
354                 idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
355                 ret = snd_usb_ctl_msg(chip->dev, usb_rcvctrlpipe(chip->dev, 0), bRequest,
356                               USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
357                               validx, idx, buf, size);
358         }
359         up_read(&chip->shutdown_rwsem);
360         snd_usb_autosuspend(chip);
361
362         if (ret < 0) {
363 error:
364                 usb_audio_err(chip,
365                         "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
366                         request, validx, idx, cval->val_type);
367                 return ret;
368         }
369
370         /* FIXME: how should we handle multiple triplets here? */
371
372         switch (request) {
373         case UAC_GET_CUR:
374                 val = buf;
375                 break;
376         case UAC_GET_MIN:
377                 val = buf + sizeof(__u16);
378                 break;
379         case UAC_GET_MAX:
380                 val = buf + sizeof(__u16) * 2;
381                 break;
382         case UAC_GET_RES:
383                 val = buf + sizeof(__u16) * 3;
384                 break;
385         default:
386                 return -EINVAL;
387         }
388
389         *value_ret = convert_signed_value(cval, snd_usb_combine_bytes(val, sizeof(__u16)));
390
391         return 0;
392 }
393
394 static int get_ctl_value(struct usb_mixer_elem_info *cval, int request,
395                          int validx, int *value_ret)
396 {
397         validx += cval->idx_off;
398
399         return (cval->head.mixer->protocol == UAC_VERSION_1) ?
400                 get_ctl_value_v1(cval, request, validx, value_ret) :
401                 get_ctl_value_v2(cval, request, validx, value_ret);
402 }
403
404 static int get_cur_ctl_value(struct usb_mixer_elem_info *cval,
405                              int validx, int *value)
406 {
407         return get_ctl_value(cval, UAC_GET_CUR, validx, value);
408 }
409
410 /* channel = 0: master, 1 = first channel */
411 static inline int get_cur_mix_raw(struct usb_mixer_elem_info *cval,
412                                   int channel, int *value)
413 {
414         return get_ctl_value(cval, UAC_GET_CUR,
415                              (cval->control << 8) | channel,
416                              value);
417 }
418
419 int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
420                              int channel, int index, int *value)
421 {
422         int err;
423
424         if (cval->cached & (1 << channel)) {
425                 *value = cval->cache_val[index];
426                 return 0;
427         }
428         err = get_cur_mix_raw(cval, channel, value);
429         if (err < 0) {
430                 if (!cval->head.mixer->ignore_ctl_error)
431                         usb_audio_dbg(cval->head.mixer->chip,
432                                 "cannot get current value for control %d ch %d: err = %d\n",
433                                       cval->control, channel, err);
434                 return err;
435         }
436         cval->cached |= 1 << channel;
437         cval->cache_val[index] = *value;
438         return 0;
439 }
440
441 /*
442  * set a mixer value
443  */
444
445 int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
446                                 int request, int validx, int value_set)
447 {
448         struct snd_usb_audio *chip = cval->head.mixer->chip;
449         unsigned char buf[2];
450         int idx = 0, val_len, err, timeout = 10;
451
452         validx += cval->idx_off;
453
454         if (cval->head.mixer->protocol == UAC_VERSION_1) {
455                 val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
456         } else { /* UAC_VERSION_2 */
457                 /* audio class v2 controls are always 2 bytes in size */
458                 val_len = sizeof(__u16);
459
460                 /* FIXME */
461                 if (request != UAC_SET_CUR) {
462                         usb_audio_dbg(chip, "RANGE setting not yet supported\n");
463                         return -EINVAL;
464                 }
465
466                 request = UAC2_CS_CUR;
467         }
468
469         value_set = convert_bytes_value(cval, value_set);
470         buf[0] = value_set & 0xff;
471         buf[1] = (value_set >> 8) & 0xff;
472         err = snd_usb_autoresume(chip);
473         if (err < 0)
474                 return -EIO;
475         down_read(&chip->shutdown_rwsem);
476         while (timeout-- > 0) {
477                 if (chip->shutdown)
478                         break;
479                 idx = snd_usb_ctrl_intf(chip) | (cval->head.id << 8);
480                 if (snd_usb_ctl_msg(chip->dev,
481                                     usb_sndctrlpipe(chip->dev, 0), request,
482                                     USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT,
483                                     validx, idx, buf, val_len) >= 0) {
484                         err = 0;
485                         goto out;
486                 }
487         }
488         usb_audio_dbg(chip, "cannot set ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d, data = %#x/%#x\n",
489                       request, validx, idx, cval->val_type, buf[0], buf[1]);
490         err = -EINVAL;
491
492  out:
493         up_read(&chip->shutdown_rwsem);
494         snd_usb_autosuspend(chip);
495         return err;
496 }
497
498 static int set_cur_ctl_value(struct usb_mixer_elem_info *cval,
499                              int validx, int value)
500 {
501         return snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, validx, value);
502 }
503
504 int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
505                              int index, int value)
506 {
507         int err;
508         unsigned int read_only = (channel == 0) ?
509                 cval->master_readonly :
510                 cval->ch_readonly & (1 << (channel - 1));
511
512         if (read_only) {
513                 usb_audio_dbg(cval->head.mixer->chip,
514                               "%s(): channel %d of control %d is read_only\n",
515                             __func__, channel, cval->control);
516                 return 0;
517         }
518
519         err = snd_usb_mixer_set_ctl_value(cval,
520                                           UAC_SET_CUR, (cval->control << 8) | channel,
521                                           value);
522         if (err < 0)
523                 return err;
524         cval->cached |= 1 << channel;
525         cval->cache_val[index] = value;
526         return 0;
527 }
528
529 /*
530  * TLV callback for mixer volume controls
531  */
532 int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag,
533                          unsigned int size, unsigned int __user *_tlv)
534 {
535         struct usb_mixer_elem_info *cval = kcontrol->private_data;
536         DECLARE_TLV_DB_MINMAX(scale, 0, 0);
537
538         if (size < sizeof(scale))
539                 return -ENOMEM;
540         scale[2] = cval->dBmin;
541         scale[3] = cval->dBmax;
542         if (copy_to_user(_tlv, scale, sizeof(scale)))
543                 return -EFAULT;
544         return 0;
545 }
546
547 /*
548  * parser routines begin here...
549  */
550
551 static int parse_audio_unit(struct mixer_build *state, int unitid);
552
553
554 /*
555  * check if the input/output channel routing is enabled on the given bitmap.
556  * used for mixer unit parser
557  */
558 static int check_matrix_bitmap(unsigned char *bmap,
559                                int ich, int och, int num_outs)
560 {
561         int idx = ich * num_outs + och;
562         return bmap[idx >> 3] & (0x80 >> (idx & 7));
563 }
564
565 /*
566  * add an alsa control element
567  * search and increment the index until an empty slot is found.
568  *
569  * if failed, give up and free the control instance.
570  */
571
572 int snd_usb_mixer_add_control(struct usb_mixer_elem_list *list,
573                               struct snd_kcontrol *kctl)
574 {
575         struct usb_mixer_interface *mixer = list->mixer;
576         int err;
577
578         while (snd_ctl_find_id(mixer->chip->card, &kctl->id))
579                 kctl->id.index++;
580         if ((err = snd_ctl_add(mixer->chip->card, kctl)) < 0) {
581                 usb_audio_dbg(mixer->chip, "cannot add control (err = %d)\n",
582                               err);
583                 return err;
584         }
585         list->kctl = kctl;
586         list->next_id_elem = mixer->id_elems[list->id];
587         mixer->id_elems[list->id] = list;
588         return 0;
589 }
590
591 /*
592  * get a terminal name string
593  */
594
595 static struct iterm_name_combo {
596         int type;
597         char *name;
598 } iterm_names[] = {
599         { 0x0300, "Output" },
600         { 0x0301, "Speaker" },
601         { 0x0302, "Headphone" },
602         { 0x0303, "HMD Audio" },
603         { 0x0304, "Desktop Speaker" },
604         { 0x0305, "Room Speaker" },
605         { 0x0306, "Com Speaker" },
606         { 0x0307, "LFE" },
607         { 0x0600, "External In" },
608         { 0x0601, "Analog In" },
609         { 0x0602, "Digital In" },
610         { 0x0603, "Line" },
611         { 0x0604, "Legacy In" },
612         { 0x0605, "IEC958 In" },
613         { 0x0606, "1394 DA Stream" },
614         { 0x0607, "1394 DV Stream" },
615         { 0x0700, "Embedded" },
616         { 0x0701, "Noise Source" },
617         { 0x0702, "Equalization Noise" },
618         { 0x0703, "CD" },
619         { 0x0704, "DAT" },
620         { 0x0705, "DCC" },
621         { 0x0706, "MiniDisk" },
622         { 0x0707, "Analog Tape" },
623         { 0x0708, "Phonograph" },
624         { 0x0709, "VCR Audio" },
625         { 0x070a, "Video Disk Audio" },
626         { 0x070b, "DVD Audio" },
627         { 0x070c, "TV Tuner Audio" },
628         { 0x070d, "Satellite Rec Audio" },
629         { 0x070e, "Cable Tuner Audio" },
630         { 0x070f, "DSS Audio" },
631         { 0x0710, "Radio Receiver" },
632         { 0x0711, "Radio Transmitter" },
633         { 0x0712, "Multi-Track Recorder" },
634         { 0x0713, "Synthesizer" },
635         { 0 },
636 };
637
638 static int get_term_name(struct mixer_build *state, struct usb_audio_term *iterm,
639                          unsigned char *name, int maxlen, int term_only)
640 {
641         struct iterm_name_combo *names;
642
643         if (iterm->name)
644                 return snd_usb_copy_string_desc(state, iterm->name,
645                                                 name, maxlen);
646
647         /* virtual type - not a real terminal */
648         if (iterm->type >> 16) {
649                 if (term_only)
650                         return 0;
651                 switch (iterm->type >> 16) {
652                 case UAC_SELECTOR_UNIT:
653                         strcpy(name, "Selector");
654                         return 8;
655                 case UAC1_PROCESSING_UNIT:
656                         strcpy(name, "Process Unit");
657                         return 12;
658                 case UAC1_EXTENSION_UNIT:
659                         strcpy(name, "Ext Unit");
660                         return 8;
661                 case UAC_MIXER_UNIT:
662                         strcpy(name, "Mixer");
663                         return 5;
664                 default:
665                         return sprintf(name, "Unit %d", iterm->id);
666                 }
667         }
668
669         switch (iterm->type & 0xff00) {
670         case 0x0100:
671                 strcpy(name, "PCM");
672                 return 3;
673         case 0x0200:
674                 strcpy(name, "Mic");
675                 return 3;
676         case 0x0400:
677                 strcpy(name, "Headset");
678                 return 7;
679         case 0x0500:
680                 strcpy(name, "Phone");
681                 return 5;
682         }
683
684         for (names = iterm_names; names->type; names++) {
685                 if (names->type == iterm->type) {
686                         strcpy(name, names->name);
687                         return strlen(names->name);
688                 }
689         }
690
691         return 0;
692 }
693
694 /*
695  * parse the source unit recursively until it reaches to a terminal
696  * or a branched unit.
697  */
698 static int check_input_term(struct mixer_build *state, int id,
699                             struct usb_audio_term *term)
700 {
701         int err;
702         void *p1;
703
704         memset(term, 0, sizeof(*term));
705         while ((p1 = find_audio_control_unit(state, id)) != NULL) {
706                 unsigned char *hdr = p1;
707                 term->id = id;
708                 switch (hdr[2]) {
709                 case UAC_INPUT_TERMINAL:
710                         if (state->mixer->protocol == UAC_VERSION_1) {
711                                 struct uac_input_terminal_descriptor *d = p1;
712                                 term->type = le16_to_cpu(d->wTerminalType);
713                                 term->channels = d->bNrChannels;
714                                 term->chconfig = le16_to_cpu(d->wChannelConfig);
715                                 term->name = d->iTerminal;
716                         } else { /* UAC_VERSION_2 */
717                                 struct uac2_input_terminal_descriptor *d = p1;
718                                 term->type = le16_to_cpu(d->wTerminalType);
719                                 term->channels = d->bNrChannels;
720                                 term->chconfig = le32_to_cpu(d->bmChannelConfig);
721                                 term->name = d->iTerminal;
722
723                                 /* call recursively to get the clock selectors */
724                                 err = check_input_term(state, d->bCSourceID, term);
725                                 if (err < 0)
726                                         return err;
727                         }
728                         return 0;
729                 case UAC_FEATURE_UNIT: {
730                         /* the header is the same for v1 and v2 */
731                         struct uac_feature_unit_descriptor *d = p1;
732                         id = d->bSourceID;
733                         break; /* continue to parse */
734                 }
735                 case UAC_MIXER_UNIT: {
736                         struct uac_mixer_unit_descriptor *d = p1;
737                         term->type = d->bDescriptorSubtype << 16; /* virtual type */
738                         term->channels = uac_mixer_unit_bNrChannels(d);
739                         term->chconfig = uac_mixer_unit_wChannelConfig(d, state->mixer->protocol);
740                         term->name = uac_mixer_unit_iMixer(d);
741                         return 0;
742                 }
743                 case UAC_SELECTOR_UNIT:
744                 case UAC2_CLOCK_SELECTOR: {
745                         struct uac_selector_unit_descriptor *d = p1;
746                         /* call recursively to retrieve the channel info */
747                         err = check_input_term(state, d->baSourceID[0], term);
748                         if (err < 0)
749                                 return err;
750                         term->type = d->bDescriptorSubtype << 16; /* virtual type */
751                         term->id = id;
752                         term->name = uac_selector_unit_iSelector(d);
753                         return 0;
754                 }
755                 case UAC1_PROCESSING_UNIT:
756                 case UAC1_EXTENSION_UNIT:
757                 /* UAC2_PROCESSING_UNIT_V2 */
758                 /* UAC2_EFFECT_UNIT */
759                 case UAC2_EXTENSION_UNIT_V2: {
760                         struct uac_processing_unit_descriptor *d = p1;
761
762                         if (state->mixer->protocol == UAC_VERSION_2 &&
763                                 hdr[2] == UAC2_EFFECT_UNIT) {
764                                 /* UAC2/UAC1 unit IDs overlap here in an
765                                  * uncompatible way. Ignore this unit for now.
766                                  */
767                                 return 0;
768                         }
769
770                         if (d->bNrInPins) {
771                                 id = d->baSourceID[0];
772                                 break; /* continue to parse */
773                         }
774                         term->type = d->bDescriptorSubtype << 16; /* virtual type */
775                         term->channels = uac_processing_unit_bNrChannels(d);
776                         term->chconfig = uac_processing_unit_wChannelConfig(d, state->mixer->protocol);
777                         term->name = uac_processing_unit_iProcessing(d, state->mixer->protocol);
778                         return 0;
779                 }
780                 case UAC2_CLOCK_SOURCE: {
781                         struct uac_clock_source_descriptor *d = p1;
782                         term->type = d->bDescriptorSubtype << 16; /* virtual type */
783                         term->id = id;
784                         term->name = d->iClockSource;
785                         return 0;
786                 }
787                 default:
788                         return -ENODEV;
789                 }
790         }
791         return -ENODEV;
792 }
793
794 /*
795  * Feature Unit
796  */
797
798 /* feature unit control information */
799 struct usb_feature_control_info {
800         const char *name;
801         unsigned int type;      /* control type (mute, volume, etc.) */
802 };
803
804 static struct usb_feature_control_info audio_feature_info[] = {
805         { "Mute",                       USB_MIXER_INV_BOOLEAN },
806         { "Volume",                     USB_MIXER_S16 },
807         { "Tone Control - Bass",        USB_MIXER_S8 },
808         { "Tone Control - Mid",         USB_MIXER_S8 },
809         { "Tone Control - Treble",      USB_MIXER_S8 },
810         { "Graphic Equalizer",          USB_MIXER_S8 }, /* FIXME: not implemeted yet */
811         { "Auto Gain Control",          USB_MIXER_BOOLEAN },
812         { "Delay Control",              USB_MIXER_U16 },
813         { "Bass Boost",                 USB_MIXER_BOOLEAN },
814         { "Loudness",                   USB_MIXER_BOOLEAN },
815         /* UAC2 specific */
816         { "Input Gain Control",         USB_MIXER_U16 },
817         { "Input Gain Pad Control",     USB_MIXER_BOOLEAN },
818         { "Phase Inverter Control",     USB_MIXER_BOOLEAN },
819 };
820
821 /* private_free callback */
822 void snd_usb_mixer_elem_free(struct snd_kcontrol *kctl)
823 {
824         kfree(kctl->private_data);
825         kctl->private_data = NULL;
826 }
827
828 /*
829  * interface to ALSA control for feature/mixer units
830  */
831
832 /* volume control quirks */
833 static void volume_control_quirks(struct usb_mixer_elem_info *cval,
834                                   struct snd_kcontrol *kctl)
835 {
836         struct snd_usb_audio *chip = cval->head.mixer->chip;
837         switch (chip->usb_id) {
838         case USB_ID(0x0763, 0x2030): /* M-Audio Fast Track C400 */
839         case USB_ID(0x0763, 0x2031): /* M-Audio Fast Track C600 */
840                 if (strcmp(kctl->id.name, "Effect Duration") == 0) {
841                         cval->min = 0x0000;
842                         cval->max = 0xffff;
843                         cval->res = 0x00e6;
844                         break;
845                 }
846                 if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
847                     strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
848                         cval->min = 0x00;
849                         cval->max = 0xff;
850                         break;
851                 }
852                 if (strstr(kctl->id.name, "Effect Return") != NULL) {
853                         cval->min = 0xb706;
854                         cval->max = 0xff7b;
855                         cval->res = 0x0073;
856                         break;
857                 }
858                 if ((strstr(kctl->id.name, "Playback Volume") != NULL) ||
859                         (strstr(kctl->id.name, "Effect Send") != NULL)) {
860                         cval->min = 0xb5fb; /* -73 dB = 0xb6ff */
861                         cval->max = 0xfcfe;
862                         cval->res = 0x0073;
863                 }
864                 break;
865
866         case USB_ID(0x0763, 0x2081): /* M-Audio Fast Track Ultra 8R */
867         case USB_ID(0x0763, 0x2080): /* M-Audio Fast Track Ultra */
868                 if (strcmp(kctl->id.name, "Effect Duration") == 0) {
869                         usb_audio_info(chip,
870                                        "set quirk for FTU Effect Duration\n");
871                         cval->min = 0x0000;
872                         cval->max = 0x7f00;
873                         cval->res = 0x0100;
874                         break;
875                 }
876                 if (strcmp(kctl->id.name, "Effect Volume") == 0 ||
877                     strcmp(kctl->id.name, "Effect Feedback Volume") == 0) {
878                         usb_audio_info(chip,
879                                        "set quirks for FTU Effect Feedback/Volume\n");
880                         cval->min = 0x00;
881                         cval->max = 0x7f;
882                         break;
883                 }
884                 break;
885
886         case USB_ID(0x0471, 0x0101):
887         case USB_ID(0x0471, 0x0104):
888         case USB_ID(0x0471, 0x0105):
889         case USB_ID(0x0672, 0x1041):
890         /* quirk for UDA1321/N101.
891          * note that detection between firmware 2.1.1.7 (N101)
892          * and later 2.1.1.21 is not very clear from datasheets.
893          * I hope that the min value is -15360 for newer firmware --jk
894          */
895                 if (!strcmp(kctl->id.name, "PCM Playback Volume") &&
896                     cval->min == -15616) {
897                         usb_audio_info(chip,
898                                  "set volume quirk for UDA1321/N101 chip\n");
899                         cval->max = -256;
900                 }
901                 break;
902
903         case USB_ID(0x046d, 0x09a4):
904                 if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
905                         usb_audio_info(chip,
906                                 "set volume quirk for QuickCam E3500\n");
907                         cval->min = 6080;
908                         cval->max = 8768;
909                         cval->res = 192;
910                 }
911                 break;
912
913         case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
914         case USB_ID(0x046d, 0x0808):
915         case USB_ID(0x046d, 0x0809):
916         case USB_ID(0x046d, 0x0819): /* Logitech Webcam C210 */
917         case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
918         case USB_ID(0x046d, 0x081d): /* HD Webcam c510 */
919         case USB_ID(0x046d, 0x0825): /* HD Webcam c270 */
920         case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
921         case USB_ID(0x046d, 0x08ca): /* Logitech Quickcam Fusion */
922         case USB_ID(0x046d, 0x0991):
923         /* Most audio usb devices lie about volume resolution.
924          * Most Logitech webcams have res = 384.
925          * Proboly there is some logitech magic behind this number --fishor
926          */
927                 if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
928                         usb_audio_info(chip,
929                                 "set resolution quirk: cval->res = 384\n");
930                         cval->res = 384;
931                 }
932                 break;
933         }
934 }
935
936 /*
937  * retrieve the minimum and maximum values for the specified control
938  */
939 static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
940                                    int default_min, struct snd_kcontrol *kctl)
941 {
942         /* for failsafe */
943         cval->min = default_min;
944         cval->max = cval->min + 1;
945         cval->res = 1;
946         cval->dBmin = cval->dBmax = 0;
947
948         if (cval->val_type == USB_MIXER_BOOLEAN ||
949             cval->val_type == USB_MIXER_INV_BOOLEAN) {
950                 cval->initialized = 1;
951         } else {
952                 int minchn = 0;
953                 if (cval->cmask) {
954                         int i;
955                         for (i = 0; i < MAX_CHANNELS; i++)
956                                 if (cval->cmask & (1 << i)) {
957                                         minchn = i + 1;
958                                         break;
959                                 }
960                 }
961                 if (get_ctl_value(cval, UAC_GET_MAX, (cval->control << 8) | minchn, &cval->max) < 0 ||
962                     get_ctl_value(cval, UAC_GET_MIN, (cval->control << 8) | minchn, &cval->min) < 0) {
963                         usb_audio_err(cval->head.mixer->chip,
964                                       "%d:%d: cannot get min/max values for control %d (id %d)\n",
965                                    cval->head.id, snd_usb_ctrl_intf(cval->head.mixer->chip),
966                                                                cval->control, cval->head.id);
967                         return -EINVAL;
968                 }
969                 if (get_ctl_value(cval, UAC_GET_RES,
970                                   (cval->control << 8) | minchn,
971                                   &cval->res) < 0) {
972                         cval->res = 1;
973                 } else {
974                         int last_valid_res = cval->res;
975
976                         while (cval->res > 1) {
977                                 if (snd_usb_mixer_set_ctl_value(cval, UAC_SET_RES,
978                                                                 (cval->control << 8) | minchn,
979                                                                 cval->res / 2) < 0)
980                                         break;
981                                 cval->res /= 2;
982                         }
983                         if (get_ctl_value(cval, UAC_GET_RES,
984                                           (cval->control << 8) | minchn, &cval->res) < 0)
985                                 cval->res = last_valid_res;
986                 }
987                 if (cval->res == 0)
988                         cval->res = 1;
989
990                 /* Additional checks for the proper resolution
991                  *
992                  * Some devices report smaller resolutions than actually
993                  * reacting.  They don't return errors but simply clip
994                  * to the lower aligned value.
995                  */
996                 if (cval->min + cval->res < cval->max) {
997                         int last_valid_res = cval->res;
998                         int saved, test, check;
999                         get_cur_mix_raw(cval, minchn, &saved);
1000                         for (;;) {
1001                                 test = saved;
1002                                 if (test < cval->max)
1003                                         test += cval->res;
1004                                 else
1005                                         test -= cval->res;
1006                                 if (test < cval->min || test > cval->max ||
1007                                     snd_usb_set_cur_mix_value(cval, minchn, 0, test) ||
1008                                     get_cur_mix_raw(cval, minchn, &check)) {
1009                                         cval->res = last_valid_res;
1010                                         break;
1011                                 }
1012                                 if (test == check)
1013                                         break;
1014                                 cval->res *= 2;
1015                         }
1016                         snd_usb_set_cur_mix_value(cval, minchn, 0, saved);
1017                 }
1018
1019                 cval->initialized = 1;
1020         }
1021
1022         if (kctl)
1023                 volume_control_quirks(cval, kctl);
1024
1025         /* USB descriptions contain the dB scale in 1/256 dB unit
1026          * while ALSA TLV contains in 1/100 dB unit
1027          */
1028         cval->dBmin = (convert_signed_value(cval, cval->min) * 100) / 256;
1029         cval->dBmax = (convert_signed_value(cval, cval->max) * 100) / 256;
1030         if (cval->dBmin > cval->dBmax) {
1031                 /* something is wrong; assume it's either from/to 0dB */
1032                 if (cval->dBmin < 0)
1033                         cval->dBmax = 0;
1034                 else if (cval->dBmin > 0)
1035                         cval->dBmin = 0;
1036                 if (cval->dBmin > cval->dBmax) {
1037                         /* totally crap, return an error */
1038                         return -EINVAL;
1039                 }
1040         }
1041
1042         return 0;
1043 }
1044
1045 #define get_min_max(cval, def)  get_min_max_with_quirks(cval, def, NULL)
1046
1047 /* get a feature/mixer unit info */
1048 static int mixer_ctl_feature_info(struct snd_kcontrol *kcontrol,
1049                                   struct snd_ctl_elem_info *uinfo)
1050 {
1051         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1052
1053         if (cval->val_type == USB_MIXER_BOOLEAN ||
1054             cval->val_type == USB_MIXER_INV_BOOLEAN)
1055                 uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
1056         else
1057                 uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1058         uinfo->count = cval->channels;
1059         if (cval->val_type == USB_MIXER_BOOLEAN ||
1060             cval->val_type == USB_MIXER_INV_BOOLEAN) {
1061                 uinfo->value.integer.min = 0;
1062                 uinfo->value.integer.max = 1;
1063         } else {
1064                 if (!cval->initialized) {
1065                         get_min_max_with_quirks(cval, 0, kcontrol);
1066                         if (cval->initialized && cval->dBmin >= cval->dBmax) {
1067                                 kcontrol->vd[0].access &= 
1068                                         ~(SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1069                                           SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK);
1070                                 snd_ctl_notify(cval->head.mixer->chip->card,
1071                                                SNDRV_CTL_EVENT_MASK_INFO,
1072                                                &kcontrol->id);
1073                         }
1074                 }
1075                 uinfo->value.integer.min = 0;
1076                 uinfo->value.integer.max =
1077                         (cval->max - cval->min + cval->res - 1) / cval->res;
1078         }
1079         return 0;
1080 }
1081
1082 /* get the current value from feature/mixer unit */
1083 static int mixer_ctl_feature_get(struct snd_kcontrol *kcontrol,
1084                                  struct snd_ctl_elem_value *ucontrol)
1085 {
1086         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1087         int c, cnt, val, err;
1088
1089         ucontrol->value.integer.value[0] = cval->min;
1090         if (cval->cmask) {
1091                 cnt = 0;
1092                 for (c = 0; c < MAX_CHANNELS; c++) {
1093                         if (!(cval->cmask & (1 << c)))
1094                                 continue;
1095                         err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &val);
1096                         if (err < 0)
1097                                 return filter_error(cval, err);
1098                         val = get_relative_value(cval, val);
1099                         ucontrol->value.integer.value[cnt] = val;
1100                         cnt++;
1101                 }
1102                 return 0;
1103         } else {
1104                 /* master channel */
1105                 err = snd_usb_get_cur_mix_value(cval, 0, 0, &val);
1106                 if (err < 0)
1107                         return filter_error(cval, err);
1108                 val = get_relative_value(cval, val);
1109                 ucontrol->value.integer.value[0] = val;
1110         }
1111         return 0;
1112 }
1113
1114 /* put the current value to feature/mixer unit */
1115 static int mixer_ctl_feature_put(struct snd_kcontrol *kcontrol,
1116                                  struct snd_ctl_elem_value *ucontrol)
1117 {
1118         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1119         int c, cnt, val, oval, err;
1120         int changed = 0;
1121
1122         if (cval->cmask) {
1123                 cnt = 0;
1124                 for (c = 0; c < MAX_CHANNELS; c++) {
1125                         if (!(cval->cmask & (1 << c)))
1126                                 continue;
1127                         err = snd_usb_get_cur_mix_value(cval, c + 1, cnt, &oval);
1128                         if (err < 0)
1129                                 return filter_error(cval, err);
1130                         val = ucontrol->value.integer.value[cnt];
1131                         val = get_abs_value(cval, val);
1132                         if (oval != val) {
1133                                 snd_usb_set_cur_mix_value(cval, c + 1, cnt, val);
1134                                 changed = 1;
1135                         }
1136                         cnt++;
1137                 }
1138         } else {
1139                 /* master channel */
1140                 err = snd_usb_get_cur_mix_value(cval, 0, 0, &oval);
1141                 if (err < 0)
1142                         return filter_error(cval, err);
1143                 val = ucontrol->value.integer.value[0];
1144                 val = get_abs_value(cval, val);
1145                 if (val != oval) {
1146                         snd_usb_set_cur_mix_value(cval, 0, 0, val);
1147                         changed = 1;
1148                 }
1149         }
1150         return changed;
1151 }
1152
1153 static struct snd_kcontrol_new usb_feature_unit_ctl = {
1154         .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1155         .name = "", /* will be filled later manually */
1156         .info = mixer_ctl_feature_info,
1157         .get = mixer_ctl_feature_get,
1158         .put = mixer_ctl_feature_put,
1159 };
1160
1161 /* the read-only variant */
1162 static struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
1163         .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1164         .name = "", /* will be filled later manually */
1165         .info = mixer_ctl_feature_info,
1166         .get = mixer_ctl_feature_get,
1167         .put = NULL,
1168 };
1169
1170 /*
1171  * This symbol is exported in order to allow the mixer quirks to
1172  * hook up to the standard feature unit control mechanism
1173  */
1174 struct snd_kcontrol_new *snd_usb_feature_unit_ctl = &usb_feature_unit_ctl;
1175
1176 /*
1177  * build a feature control
1178  */
1179 static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
1180 {
1181         return strlcat(kctl->id.name, str, sizeof(kctl->id.name));
1182 }
1183
1184 /*
1185  * A lot of headsets/headphones have a "Speaker" mixer. Make sure we
1186  * rename it to "Headphone". We determine if something is a headphone
1187  * similar to how udev determines form factor.
1188  */
1189 static void check_no_speaker_on_headset(struct snd_kcontrol *kctl,
1190                                         struct snd_card *card)
1191 {
1192         const char *names_to_check[] = {
1193                 "Headset", "headset", "Headphone", "headphone", NULL};
1194         const char **s;
1195         bool found = false;
1196
1197         if (strcmp("Speaker", kctl->id.name))
1198                 return;
1199
1200         for (s = names_to_check; *s; s++)
1201                 if (strstr(card->shortname, *s)) {
1202                         found = true;
1203                         break;
1204                 }
1205
1206         if (!found)
1207                 return;
1208
1209         strlcpy(kctl->id.name, "Headphone", sizeof(kctl->id.name));
1210 }
1211
1212 static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
1213                               unsigned int ctl_mask, int control,
1214                               struct usb_audio_term *iterm, int unitid,
1215                               int readonly_mask)
1216 {
1217         struct uac_feature_unit_descriptor *desc = raw_desc;
1218         unsigned int len = 0;
1219         int mapped_name = 0;
1220         int nameid = uac_feature_unit_iFeature(desc);
1221         struct snd_kcontrol *kctl;
1222         struct usb_mixer_elem_info *cval;
1223         const struct usbmix_name_map *map;
1224         unsigned int range;
1225
1226         control++; /* change from zero-based to 1-based value */
1227
1228         if (control == UAC_FU_GRAPHIC_EQUALIZER) {
1229                 /* FIXME: not supported yet */
1230                 return;
1231         }
1232
1233         map = find_map(state, unitid, control);
1234         if (check_ignored_ctl(map))
1235                 return;
1236
1237         cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1238         if (!cval)
1239                 return;
1240         snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
1241         cval->control = control;
1242         cval->cmask = ctl_mask;
1243         cval->val_type = audio_feature_info[control-1].type;
1244         if (ctl_mask == 0) {
1245                 cval->channels = 1;     /* master channel */
1246                 cval->master_readonly = readonly_mask;
1247         } else {
1248                 int i, c = 0;
1249                 for (i = 0; i < 16; i++)
1250                         if (ctl_mask & (1 << i))
1251                                 c++;
1252                 cval->channels = c;
1253                 cval->ch_readonly = readonly_mask;
1254         }
1255
1256         /*
1257          * If all channels in the mask are marked read-only, make the control
1258          * read-only. snd_usb_set_cur_mix_value() will check the mask again and won't
1259          * issue write commands to read-only channels.
1260          */
1261         if (cval->channels == readonly_mask)
1262                 kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
1263         else
1264                 kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1265
1266         if (!kctl) {
1267                 usb_audio_err(state->chip, "cannot malloc kcontrol\n");
1268                 kfree(cval);
1269                 return;
1270         }
1271         kctl->private_free = snd_usb_mixer_elem_free;
1272
1273         len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1274         mapped_name = len != 0;
1275         if (!len && nameid)
1276                 len = snd_usb_copy_string_desc(state, nameid,
1277                                 kctl->id.name, sizeof(kctl->id.name));
1278
1279         switch (control) {
1280         case UAC_FU_MUTE:
1281         case UAC_FU_VOLUME:
1282                 /*
1283                  * determine the control name.  the rule is:
1284                  * - if a name id is given in descriptor, use it.
1285                  * - if the connected input can be determined, then use the name
1286                  *   of terminal type.
1287                  * - if the connected output can be determined, use it.
1288                  * - otherwise, anonymous name.
1289                  */
1290                 if (!len) {
1291                         len = get_term_name(state, iterm, kctl->id.name,
1292                                             sizeof(kctl->id.name), 1);
1293                         if (!len)
1294                                 len = get_term_name(state, &state->oterm,
1295                                                     kctl->id.name,
1296                                                     sizeof(kctl->id.name), 1);
1297                         if (!len)
1298                                 snprintf(kctl->id.name, sizeof(kctl->id.name),
1299                                          "Feature %d", unitid);
1300                 }
1301
1302                 if (!mapped_name)
1303                         check_no_speaker_on_headset(kctl, state->mixer->chip->card);
1304
1305                 /*
1306                  * determine the stream direction:
1307                  * if the connected output is USB stream, then it's likely a
1308                  * capture stream.  otherwise it should be playback (hopefully :)
1309                  */
1310                 if (!mapped_name && !(state->oterm.type >> 16)) {
1311                         if ((state->oterm.type & 0xff00) == 0x0100)
1312                                 append_ctl_name(kctl, " Capture");
1313                         else
1314                                 append_ctl_name(kctl, " Playback");
1315                 }
1316                 append_ctl_name(kctl, control == UAC_FU_MUTE ?
1317                                 " Switch" : " Volume");
1318                 break;
1319         default:
1320                 if (!len)
1321                         strlcpy(kctl->id.name, audio_feature_info[control-1].name,
1322                                 sizeof(kctl->id.name));
1323                 break;
1324         }
1325
1326         /* get min/max values */
1327         get_min_max_with_quirks(cval, 0, kctl);
1328
1329         if (control == UAC_FU_VOLUME) {
1330                 check_mapped_dB(map, cval);
1331                 if (cval->dBmin < cval->dBmax || !cval->initialized) {
1332                         kctl->tlv.c = snd_usb_mixer_vol_tlv;
1333                         kctl->vd[0].access |=
1334                                 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1335                                 SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1336                 }
1337         }
1338
1339         range = (cval->max - cval->min) / cval->res;
1340         /*
1341          * Are there devices with volume range more than 255? I use a bit more
1342          * to be sure. 384 is a resolution magic number found on Logitech
1343          * devices. It will definitively catch all buggy Logitech devices.
1344          */
1345         if (range > 384) {
1346                 usb_audio_warn(state->chip,
1347                                "Warning! Unlikely big volume range (=%u), cval->res is probably wrong.",
1348                                range);
1349                 usb_audio_warn(state->chip,
1350                                "[%d] FU [%s] ch = %d, val = %d/%d/%d",
1351                                cval->head.id, kctl->id.name, cval->channels,
1352                                cval->min, cval->max, cval->res);
1353         }
1354
1355         usb_audio_dbg(state->chip, "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
1356                       cval->head.id, kctl->id.name, cval->channels,
1357                       cval->min, cval->max, cval->res);
1358         snd_usb_mixer_add_control(&cval->head, kctl);
1359 }
1360
1361 /*
1362  * parse a feature unit
1363  *
1364  * most of controls are defined here.
1365  */
1366 static int parse_audio_feature_unit(struct mixer_build *state, int unitid,
1367                                     void *_ftr)
1368 {
1369         int channels, i, j;
1370         struct usb_audio_term iterm;
1371         unsigned int master_bits, first_ch_bits;
1372         int err, csize;
1373         struct uac_feature_unit_descriptor *hdr = _ftr;
1374         __u8 *bmaControls;
1375
1376         if (state->mixer->protocol == UAC_VERSION_1) {
1377                 csize = hdr->bControlSize;
1378                 if (!csize) {
1379                         usb_audio_dbg(state->chip,
1380                                       "unit %u: invalid bControlSize == 0\n",
1381                                       unitid);
1382                         return -EINVAL;
1383                 }
1384                 channels = (hdr->bLength - 7) / csize - 1;
1385                 bmaControls = hdr->bmaControls;
1386                 if (hdr->bLength < 7 + csize) {
1387                         usb_audio_err(state->chip,
1388                                       "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1389                                       unitid);
1390                         return -EINVAL;
1391                 }
1392         } else {
1393                 struct uac2_feature_unit_descriptor *ftr = _ftr;
1394                 csize = 4;
1395                 channels = (hdr->bLength - 6) / 4 - 1;
1396                 bmaControls = ftr->bmaControls;
1397                 if (hdr->bLength < 6 + csize) {
1398                         usb_audio_err(state->chip,
1399                                       "unit %u: invalid UAC_FEATURE_UNIT descriptor\n",
1400                                       unitid);
1401                         return -EINVAL;
1402                 }
1403         }
1404
1405         /* parse the source unit */
1406         if ((err = parse_audio_unit(state, hdr->bSourceID)) < 0)
1407                 return err;
1408
1409         /* determine the input source type and name */
1410         err = check_input_term(state, hdr->bSourceID, &iterm);
1411         if (err < 0)
1412                 return err;
1413
1414         master_bits = snd_usb_combine_bytes(bmaControls, csize);
1415         /* master configuration quirks */
1416         switch (state->chip->usb_id) {
1417         case USB_ID(0x08bb, 0x2702):
1418                 usb_audio_info(state->chip,
1419                                "usbmixer: master volume quirk for PCM2702 chip\n");
1420                 /* disable non-functional volume control */
1421                 master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
1422                 break;
1423         case USB_ID(0x1130, 0xf211):
1424                 usb_audio_info(state->chip,
1425                                "usbmixer: volume control quirk for Tenx TP6911 Audio Headset\n");
1426                 /* disable non-functional volume control */
1427                 channels = 0;
1428                 break;
1429
1430         }
1431         if (channels > 0)
1432                 first_ch_bits = snd_usb_combine_bytes(bmaControls + csize, csize);
1433         else
1434                 first_ch_bits = 0;
1435
1436         if (state->mixer->protocol == UAC_VERSION_1) {
1437                 /* check all control types */
1438                 for (i = 0; i < 10; i++) {
1439                         unsigned int ch_bits = 0;
1440                         for (j = 0; j < channels; j++) {
1441                                 unsigned int mask;
1442
1443                                 mask = snd_usb_combine_bytes(bmaControls +
1444                                                              csize * (j+1), csize);
1445                                 if (mask & (1 << i))
1446                                         ch_bits |= (1 << j);
1447                         }
1448                         /* audio class v1 controls are never read-only */
1449
1450                         /*
1451                          * The first channel must be set
1452                          * (for ease of programming).
1453                          */
1454                         if (ch_bits & 1)
1455                                 build_feature_ctl(state, _ftr, ch_bits, i,
1456                                                   &iterm, unitid, 0);
1457                         if (master_bits & (1 << i))
1458                                 build_feature_ctl(state, _ftr, 0, i, &iterm,
1459                                                   unitid, 0);
1460                 }
1461         } else { /* UAC_VERSION_2 */
1462                 for (i = 0; i < ARRAY_SIZE(audio_feature_info); i++) {
1463                         unsigned int ch_bits = 0;
1464                         unsigned int ch_read_only = 0;
1465
1466                         for (j = 0; j < channels; j++) {
1467                                 unsigned int mask;
1468
1469                                 mask = snd_usb_combine_bytes(bmaControls +
1470                                                              csize * (j+1), csize);
1471                                 if (uac2_control_is_readable(mask, i)) {
1472                                         ch_bits |= (1 << j);
1473                                         if (!uac2_control_is_writeable(mask, i))
1474                                                 ch_read_only |= (1 << j);
1475                                 }
1476                         }
1477
1478                         /*
1479                          * NOTE: build_feature_ctl() will mark the control
1480                          * read-only if all channels are marked read-only in
1481                          * the descriptors. Otherwise, the control will be
1482                          * reported as writeable, but the driver will not
1483                          * actually issue a write command for read-only
1484                          * channels.
1485                          */
1486
1487                         /*
1488                          * The first channel must be set
1489                          * (for ease of programming).
1490                          */
1491                         if (ch_bits & 1)
1492                                 build_feature_ctl(state, _ftr, ch_bits, i,
1493                                                   &iterm, unitid, ch_read_only);
1494                         if (uac2_control_is_readable(master_bits, i))
1495                                 build_feature_ctl(state, _ftr, 0, i, &iterm, unitid,
1496                                                   !uac2_control_is_writeable(master_bits, i));
1497                 }
1498         }
1499
1500         return 0;
1501 }
1502
1503 /*
1504  * Mixer Unit
1505  */
1506
1507 /*
1508  * build a mixer unit control
1509  *
1510  * the callbacks are identical with feature unit.
1511  * input channel number (zero based) is given in control field instead.
1512  */
1513 static void build_mixer_unit_ctl(struct mixer_build *state,
1514                                  struct uac_mixer_unit_descriptor *desc,
1515                                  int in_pin, int in_ch, int unitid,
1516                                  struct usb_audio_term *iterm)
1517 {
1518         struct usb_mixer_elem_info *cval;
1519         unsigned int num_outs = uac_mixer_unit_bNrChannels(desc);
1520         unsigned int i, len;
1521         struct snd_kcontrol *kctl;
1522         const struct usbmix_name_map *map;
1523
1524         map = find_map(state, unitid, 0);
1525         if (check_ignored_ctl(map))
1526                 return;
1527
1528         cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1529         if (!cval)
1530                 return;
1531
1532         snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
1533         cval->control = in_ch + 1; /* based on 1 */
1534         cval->val_type = USB_MIXER_S16;
1535         for (i = 0; i < num_outs; i++) {
1536                 __u8 *c = uac_mixer_unit_bmControls(desc, state->mixer->protocol);
1537
1538                 if (check_matrix_bitmap(c, in_ch, i, num_outs)) {
1539                         cval->cmask |= (1 << i);
1540                         cval->channels++;
1541                 }
1542         }
1543
1544         /* get min/max values */
1545         get_min_max(cval, 0);
1546
1547         kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
1548         if (!kctl) {
1549                 usb_audio_err(state->chip, "cannot malloc kcontrol\n");
1550                 kfree(cval);
1551                 return;
1552         }
1553         kctl->private_free = snd_usb_mixer_elem_free;
1554
1555         len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
1556         if (!len)
1557                 len = get_term_name(state, iterm, kctl->id.name,
1558                                     sizeof(kctl->id.name), 0);
1559         if (!len)
1560                 len = sprintf(kctl->id.name, "Mixer Source %d", in_ch + 1);
1561         append_ctl_name(kctl, " Volume");
1562
1563         usb_audio_dbg(state->chip, "[%d] MU [%s] ch = %d, val = %d/%d\n",
1564                     cval->head.id, kctl->id.name, cval->channels, cval->min, cval->max);
1565         snd_usb_mixer_add_control(&cval->head, kctl);
1566 }
1567
1568 /*
1569  * parse a mixer unit
1570  */
1571 static int parse_audio_mixer_unit(struct mixer_build *state, int unitid,
1572                                   void *raw_desc)
1573 {
1574         struct uac_mixer_unit_descriptor *desc = raw_desc;
1575         struct usb_audio_term iterm;
1576         int input_pins, num_ins, num_outs;
1577         int pin, ich, err;
1578
1579         if (desc->bLength < 11 || !(input_pins = desc->bNrInPins) ||
1580             !(num_outs = uac_mixer_unit_bNrChannels(desc))) {
1581                 usb_audio_err(state->chip,
1582                               "invalid MIXER UNIT descriptor %d\n",
1583                               unitid);
1584                 return -EINVAL;
1585         }
1586
1587         num_ins = 0;
1588         ich = 0;
1589         for (pin = 0; pin < input_pins; pin++) {
1590                 err = parse_audio_unit(state, desc->baSourceID[pin]);
1591                 if (err < 0)
1592                         continue;
1593                 /* no bmControls field (e.g. Maya44) -> ignore */
1594                 if (desc->bLength <= 10 + input_pins)
1595                         continue;
1596                 err = check_input_term(state, desc->baSourceID[pin], &iterm);
1597                 if (err < 0)
1598                         return err;
1599                 num_ins += iterm.channels;
1600                 for (; ich < num_ins; ich++) {
1601                         int och, ich_has_controls = 0;
1602
1603                         for (och = 0; och < num_outs; och++) {
1604                                 __u8 *c = uac_mixer_unit_bmControls(desc,
1605                                                 state->mixer->protocol);
1606
1607                                 if (check_matrix_bitmap(c, ich, och, num_outs)) {
1608                                         ich_has_controls = 1;
1609                                         break;
1610                                 }
1611                         }
1612                         if (ich_has_controls)
1613                                 build_mixer_unit_ctl(state, desc, pin, ich,
1614                                                      unitid, &iterm);
1615                 }
1616         }
1617         return 0;
1618 }
1619
1620 /*
1621  * Processing Unit / Extension Unit
1622  */
1623
1624 /* get callback for processing/extension unit */
1625 static int mixer_ctl_procunit_get(struct snd_kcontrol *kcontrol,
1626                                   struct snd_ctl_elem_value *ucontrol)
1627 {
1628         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1629         int err, val;
1630
1631         err = get_cur_ctl_value(cval, cval->control << 8, &val);
1632         if (err < 0) {
1633                 ucontrol->value.integer.value[0] = cval->min;
1634                 return filter_error(cval, err);
1635         }
1636         val = get_relative_value(cval, val);
1637         ucontrol->value.integer.value[0] = val;
1638         return 0;
1639 }
1640
1641 /* put callback for processing/extension unit */
1642 static int mixer_ctl_procunit_put(struct snd_kcontrol *kcontrol,
1643                                   struct snd_ctl_elem_value *ucontrol)
1644 {
1645         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1646         int val, oval, err;
1647
1648         err = get_cur_ctl_value(cval, cval->control << 8, &oval);
1649         if (err < 0)
1650                 return filter_error(cval, err);
1651         val = ucontrol->value.integer.value[0];
1652         val = get_abs_value(cval, val);
1653         if (val != oval) {
1654                 set_cur_ctl_value(cval, cval->control << 8, val);
1655                 return 1;
1656         }
1657         return 0;
1658 }
1659
1660 /* alsa control interface for processing/extension unit */
1661 static struct snd_kcontrol_new mixer_procunit_ctl = {
1662         .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1663         .name = "", /* will be filled later */
1664         .info = mixer_ctl_feature_info,
1665         .get = mixer_ctl_procunit_get,
1666         .put = mixer_ctl_procunit_put,
1667 };
1668
1669 /*
1670  * predefined data for processing units
1671  */
1672 struct procunit_value_info {
1673         int control;
1674         char *suffix;
1675         int val_type;
1676         int min_value;
1677 };
1678
1679 struct procunit_info {
1680         int type;
1681         char *name;
1682         struct procunit_value_info *values;
1683 };
1684
1685 static struct procunit_value_info updown_proc_info[] = {
1686         { UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1687         { UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
1688         { 0 }
1689 };
1690 static struct procunit_value_info prologic_proc_info[] = {
1691         { UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1692         { UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
1693         { 0 }
1694 };
1695 static struct procunit_value_info threed_enh_proc_info[] = {
1696         { UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1697         { UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
1698         { 0 }
1699 };
1700 static struct procunit_value_info reverb_proc_info[] = {
1701         { UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1702         { UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
1703         { UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
1704         { UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
1705         { 0 }
1706 };
1707 static struct procunit_value_info chorus_proc_info[] = {
1708         { UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1709         { UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
1710         { UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
1711         { UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
1712         { 0 }
1713 };
1714 static struct procunit_value_info dcr_proc_info[] = {
1715         { UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
1716         { UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
1717         { UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
1718         { UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
1719         { UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
1720         { UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
1721         { 0 }
1722 };
1723
1724 static struct procunit_info procunits[] = {
1725         { UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
1726         { UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
1727         { UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
1728         { UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
1729         { UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
1730         { UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
1731         { 0 },
1732 };
1733 /*
1734  * predefined data for extension units
1735  */
1736 static struct procunit_value_info clock_rate_xu_info[] = {
1737         { USB_XU_CLOCK_RATE_SELECTOR, "Selector", USB_MIXER_U8, 0 },
1738         { 0 }
1739 };
1740 static struct procunit_value_info clock_source_xu_info[] = {
1741         { USB_XU_CLOCK_SOURCE_SELECTOR, "External", USB_MIXER_BOOLEAN },
1742         { 0 }
1743 };
1744 static struct procunit_value_info spdif_format_xu_info[] = {
1745         { USB_XU_DIGITAL_FORMAT_SELECTOR, "SPDIF/AC3", USB_MIXER_BOOLEAN },
1746         { 0 }
1747 };
1748 static struct procunit_value_info soft_limit_xu_info[] = {
1749         { USB_XU_SOFT_LIMIT_SELECTOR, " ", USB_MIXER_BOOLEAN },
1750         { 0 }
1751 };
1752 static struct procunit_info extunits[] = {
1753         { USB_XU_CLOCK_RATE, "Clock rate", clock_rate_xu_info },
1754         { USB_XU_CLOCK_SOURCE, "DigitalIn CLK source", clock_source_xu_info },
1755         { USB_XU_DIGITAL_IO_STATUS, "DigitalOut format:", spdif_format_xu_info },
1756         { USB_XU_DEVICE_OPTIONS, "AnalogueIn Soft Limit", soft_limit_xu_info },
1757         { 0 }
1758 };
1759
1760 /*
1761  * build a processing/extension unit
1762  */
1763 static int build_audio_procunit(struct mixer_build *state, int unitid,
1764                                 void *raw_desc, struct procunit_info *list,
1765                                 char *name)
1766 {
1767         struct uac_processing_unit_descriptor *desc = raw_desc;
1768         int num_ins = desc->bNrInPins;
1769         struct usb_mixer_elem_info *cval;
1770         struct snd_kcontrol *kctl;
1771         int i, err, nameid, type, len;
1772         struct procunit_info *info;
1773         struct procunit_value_info *valinfo;
1774         const struct usbmix_name_map *map;
1775         static struct procunit_value_info default_value_info[] = {
1776                 { 0x01, "Switch", USB_MIXER_BOOLEAN },
1777                 { 0 }
1778         };
1779         static struct procunit_info default_info = {
1780                 0, NULL, default_value_info
1781         };
1782
1783         if (desc->bLength < 13 || desc->bLength < 13 + num_ins ||
1784             desc->bLength < num_ins + uac_processing_unit_bControlSize(desc, state->mixer->protocol)) {
1785                 usb_audio_err(state->chip, "invalid %s descriptor (id %d)\n", name, unitid);
1786                 return -EINVAL;
1787         }
1788
1789         for (i = 0; i < num_ins; i++) {
1790                 if ((err = parse_audio_unit(state, desc->baSourceID[i])) < 0)
1791                         return err;
1792         }
1793
1794         type = le16_to_cpu(desc->wProcessType);
1795         for (info = list; info && info->type; info++)
1796                 if (info->type == type)
1797                         break;
1798         if (!info || !info->type)
1799                 info = &default_info;
1800
1801         for (valinfo = info->values; valinfo->control; valinfo++) {
1802                 __u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);
1803
1804                 if (!(controls[valinfo->control / 8] & (1 << ((valinfo->control % 8) - 1))))
1805                         continue;
1806                 map = find_map(state, unitid, valinfo->control);
1807                 if (check_ignored_ctl(map))
1808                         continue;
1809                 cval = kzalloc(sizeof(*cval), GFP_KERNEL);
1810                 if (!cval)
1811                         return -ENOMEM;
1812                 snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
1813                 cval->control = valinfo->control;
1814                 cval->val_type = valinfo->val_type;
1815                 cval->channels = 1;
1816
1817                 /* get min/max values */
1818                 if (type == UAC_PROCESS_UP_DOWNMIX && cval->control == UAC_UD_MODE_SELECT) {
1819                         __u8 *control_spec = uac_processing_unit_specific(desc, state->mixer->protocol);
1820                         /* FIXME: hard-coded */
1821                         cval->min = 1;
1822                         cval->max = control_spec[0];
1823                         cval->res = 1;
1824                         cval->initialized = 1;
1825                 } else {
1826                         if (type == USB_XU_CLOCK_RATE) {
1827                                 /*
1828                                  * E-Mu USB 0404/0202/TrackerPre/0204
1829                                  * samplerate control quirk
1830                                  */
1831                                 cval->min = 0;
1832                                 cval->max = 5;
1833                                 cval->res = 1;
1834                                 cval->initialized = 1;
1835                         } else
1836                                 get_min_max(cval, valinfo->min_value);
1837                 }
1838
1839                 kctl = snd_ctl_new1(&mixer_procunit_ctl, cval);
1840                 if (!kctl) {
1841                         kfree(cval);
1842                         return -ENOMEM;
1843                 }
1844                 kctl->private_free = snd_usb_mixer_elem_free;
1845
1846                 if (check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name))) {
1847                         /* nothing */ ;
1848                 } else if (info->name) {
1849                         strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
1850                 } else {
1851                         nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
1852                         len = 0;
1853                         if (nameid)
1854                                 len = snd_usb_copy_string_desc(state, nameid,
1855                                                                kctl->id.name,
1856                                                                sizeof(kctl->id.name));
1857                         if (!len)
1858                                 strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
1859                 }
1860                 append_ctl_name(kctl, " ");
1861                 append_ctl_name(kctl, valinfo->suffix);
1862
1863                 usb_audio_dbg(state->chip,
1864                               "[%d] PU [%s] ch = %d, val = %d/%d\n",
1865                               cval->head.id, kctl->id.name, cval->channels,
1866                               cval->min, cval->max);
1867
1868                 err = snd_usb_mixer_add_control(&cval->head, kctl);
1869                 if (err < 0)
1870                         return err;
1871         }
1872         return 0;
1873 }
1874
1875 static int parse_audio_processing_unit(struct mixer_build *state, int unitid,
1876                                        void *raw_desc)
1877 {
1878         return build_audio_procunit(state, unitid, raw_desc,
1879                                     procunits, "Processing Unit");
1880 }
1881
1882 static int parse_audio_extension_unit(struct mixer_build *state, int unitid,
1883                                       void *raw_desc)
1884 {
1885         /*
1886          * Note that we parse extension units with processing unit descriptors.
1887          * That's ok as the layout is the same.
1888          */
1889         return build_audio_procunit(state, unitid, raw_desc,
1890                                     extunits, "Extension Unit");
1891 }
1892
1893 /*
1894  * Selector Unit
1895  */
1896
1897 /*
1898  * info callback for selector unit
1899  * use an enumerator type for routing
1900  */
1901 static int mixer_ctl_selector_info(struct snd_kcontrol *kcontrol,
1902                                    struct snd_ctl_elem_info *uinfo)
1903 {
1904         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1905         const char **itemlist = (const char **)kcontrol->private_value;
1906
1907         if (snd_BUG_ON(!itemlist))
1908                 return -EINVAL;
1909         return snd_ctl_enum_info(uinfo, 1, cval->max, itemlist);
1910 }
1911
1912 /* get callback for selector unit */
1913 static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol,
1914                                   struct snd_ctl_elem_value *ucontrol)
1915 {
1916         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1917         int val, err;
1918
1919         err = get_cur_ctl_value(cval, cval->control << 8, &val);
1920         if (err < 0) {
1921                 ucontrol->value.enumerated.item[0] = 0;
1922                 return filter_error(cval, err);
1923         }
1924         val = get_relative_value(cval, val);
1925         ucontrol->value.enumerated.item[0] = val;
1926         return 0;
1927 }
1928
1929 /* put callback for selector unit */
1930 static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol,
1931                                   struct snd_ctl_elem_value *ucontrol)
1932 {
1933         struct usb_mixer_elem_info *cval = kcontrol->private_data;
1934         int val, oval, err;
1935
1936         err = get_cur_ctl_value(cval, cval->control << 8, &oval);
1937         if (err < 0)
1938                 return filter_error(cval, err);
1939         val = ucontrol->value.enumerated.item[0];
1940         val = get_abs_value(cval, val);
1941         if (val != oval) {
1942                 set_cur_ctl_value(cval, cval->control << 8, val);
1943                 return 1;
1944         }
1945         return 0;
1946 }
1947
1948 /* alsa control interface for selector unit */
1949 static struct snd_kcontrol_new mixer_selectunit_ctl = {
1950         .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1951         .name = "", /* will be filled later */
1952         .info = mixer_ctl_selector_info,
1953         .get = mixer_ctl_selector_get,
1954         .put = mixer_ctl_selector_put,
1955 };
1956
1957 /*
1958  * private free callback.
1959  * free both private_data and private_value
1960  */
1961 static void usb_mixer_selector_elem_free(struct snd_kcontrol *kctl)
1962 {
1963         int i, num_ins = 0;
1964
1965         if (kctl->private_data) {
1966                 struct usb_mixer_elem_info *cval = kctl->private_data;
1967                 num_ins = cval->max;
1968                 kfree(cval);
1969                 kctl->private_data = NULL;
1970         }
1971         if (kctl->private_value) {
1972                 char **itemlist = (char **)kctl->private_value;
1973                 for (i = 0; i < num_ins; i++)
1974                         kfree(itemlist[i]);
1975                 kfree(itemlist);
1976                 kctl->private_value = 0;
1977         }
1978 }
1979
1980 /*
1981  * parse a selector unit
1982  */
1983 static int parse_audio_selector_unit(struct mixer_build *state, int unitid,
1984                                      void *raw_desc)
1985 {
1986         struct uac_selector_unit_descriptor *desc = raw_desc;
1987         unsigned int i, nameid, len;
1988         int err;
1989         struct usb_mixer_elem_info *cval;
1990         struct snd_kcontrol *kctl;
1991         const struct usbmix_name_map *map;
1992         char **namelist;
1993
1994         if (!desc->bNrInPins || desc->bLength < 5 + desc->bNrInPins) {
1995                 usb_audio_err(state->chip,
1996                         "invalid SELECTOR UNIT descriptor %d\n", unitid);
1997                 return -EINVAL;
1998         }
1999
2000         for (i = 0; i < desc->bNrInPins; i++) {
2001                 if ((err = parse_audio_unit(state, desc->baSourceID[i])) < 0)
2002                         return err;
2003         }
2004
2005         if (desc->bNrInPins == 1) /* only one ? nonsense! */
2006                 return 0;
2007
2008         map = find_map(state, unitid, 0);
2009         if (check_ignored_ctl(map))
2010                 return 0;
2011
2012         cval = kzalloc(sizeof(*cval), GFP_KERNEL);
2013         if (!cval)
2014                 return -ENOMEM;
2015         snd_usb_mixer_elem_init_std(&cval->head, state->mixer, unitid);
2016         cval->val_type = USB_MIXER_U8;
2017         cval->channels = 1;
2018         cval->min = 1;
2019         cval->max = desc->bNrInPins;
2020         cval->res = 1;
2021         cval->initialized = 1;
2022
2023         if (state->mixer->protocol == UAC_VERSION_1)
2024                 cval->control = 0;
2025         else /* UAC_VERSION_2 */
2026                 cval->control = (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR) ?
2027                         UAC2_CX_CLOCK_SELECTOR : UAC2_SU_SELECTOR;
2028
2029         namelist = kmalloc(sizeof(char *) * desc->bNrInPins, GFP_KERNEL);
2030         if (!namelist) {
2031                 kfree(cval);
2032                 return -ENOMEM;
2033         }
2034 #define MAX_ITEM_NAME_LEN       64
2035         for (i = 0; i < desc->bNrInPins; i++) {
2036                 struct usb_audio_term iterm;
2037                 len = 0;
2038                 namelist[i] = kmalloc(MAX_ITEM_NAME_LEN, GFP_KERNEL);
2039                 if (!namelist[i]) {
2040                         while (i--)
2041                                 kfree(namelist[i]);
2042                         kfree(namelist);
2043                         kfree(cval);
2044                         return -ENOMEM;
2045                 }
2046                 len = check_mapped_selector_name(state, unitid, i, namelist[i],
2047                                                  MAX_ITEM_NAME_LEN);
2048                 if (! len && check_input_term(state, desc->baSourceID[i], &iterm) >= 0)
2049                         len = get_term_name(state, &iterm, namelist[i], MAX_ITEM_NAME_LEN, 0);
2050                 if (! len)
2051                         sprintf(namelist[i], "Input %u", i);
2052         }
2053
2054         kctl = snd_ctl_new1(&mixer_selectunit_ctl, cval);
2055         if (! kctl) {
2056                 usb_audio_err(state->chip, "cannot malloc kcontrol\n");
2057                 kfree(namelist);
2058                 kfree(cval);
2059                 return -ENOMEM;
2060         }
2061         kctl->private_value = (unsigned long)namelist;
2062         kctl->private_free = usb_mixer_selector_elem_free;
2063
2064         nameid = uac_selector_unit_iSelector(desc);
2065         len = check_mapped_name(map, kctl->id.name, sizeof(kctl->id.name));
2066         if (len)
2067                 ;
2068         else if (nameid)
2069                 snd_usb_copy_string_desc(state, nameid, kctl->id.name,
2070                                          sizeof(kctl->id.name));
2071         else {
2072                 len = get_term_name(state, &state->oterm,
2073                                     kctl->id.name, sizeof(kctl->id.name), 0);
2074                 if (!len)
2075                         strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
2076
2077                 if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR)
2078                         append_ctl_name(kctl, " Clock Source");
2079                 else if ((state->oterm.type & 0xff00) == 0x0100)
2080                         append_ctl_name(kctl, " Capture Source");
2081                 else
2082                         append_ctl_name(kctl, " Playback Source");
2083         }
2084
2085         usb_audio_dbg(state->chip, "[%d] SU [%s] items = %d\n",
2086                     cval->head.id, kctl->id.name, desc->bNrInPins);
2087         return snd_usb_mixer_add_control(&cval->head, kctl);
2088 }
2089
2090 /*
2091  * parse an audio unit recursively
2092  */
2093
2094 static int parse_audio_unit(struct mixer_build *state, int unitid)
2095 {
2096         unsigned char *p1;
2097
2098         if (test_and_set_bit(unitid, state->unitbitmap))
2099                 return 0; /* the unit already visited */
2100
2101         p1 = find_audio_control_unit(state, unitid);
2102         if (!p1) {
2103                 usb_audio_err(state->chip, "unit %d not found!\n", unitid);
2104                 return -EINVAL;
2105         }
2106
2107         switch (p1[2]) {
2108         case UAC_INPUT_TERMINAL:
2109         case UAC2_CLOCK_SOURCE:
2110                 return 0; /* NOP */
2111         case UAC_MIXER_UNIT:
2112                 return parse_audio_mixer_unit(state, unitid, p1);
2113         case UAC_SELECTOR_UNIT:
2114         case UAC2_CLOCK_SELECTOR:
2115                 return parse_audio_selector_unit(state, unitid, p1);
2116         case UAC_FEATURE_UNIT:
2117                 return parse_audio_feature_unit(state, unitid, p1);
2118         case UAC1_PROCESSING_UNIT:
2119         /*   UAC2_EFFECT_UNIT has the same value */
2120                 if (state->mixer->protocol == UAC_VERSION_1)
2121                         return parse_audio_processing_unit(state, unitid, p1);
2122                 else
2123                         return 0; /* FIXME - effect units not implemented yet */
2124         case UAC1_EXTENSION_UNIT:
2125         /*   UAC2_PROCESSING_UNIT_V2 has the same value */
2126                 if (state->mixer->protocol == UAC_VERSION_1)
2127                         return parse_audio_extension_unit(state, unitid, p1);
2128                 else /* UAC_VERSION_2 */
2129                         return parse_audio_processing_unit(state, unitid, p1);
2130         case UAC2_EXTENSION_UNIT_V2:
2131                 return parse_audio_extension_unit(state, unitid, p1);
2132         default:
2133                 usb_audio_err(state->chip,
2134                         "unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
2135                 return -EINVAL;
2136         }
2137 }
2138
2139 static void snd_usb_mixer_free(struct usb_mixer_interface *mixer)
2140 {
2141         kfree(mixer->id_elems);
2142         if (mixer->urb) {
2143                 kfree(mixer->urb->transfer_buffer);
2144                 usb_free_urb(mixer->urb);
2145         }
2146         usb_free_urb(mixer->rc_urb);
2147         kfree(mixer->rc_setup_packet);
2148         kfree(mixer);
2149 }
2150
2151 static int snd_usb_mixer_dev_free(struct snd_device *device)
2152 {
2153         struct usb_mixer_interface *mixer = device->device_data;
2154         snd_usb_mixer_free(mixer);
2155         return 0;
2156 }
2157
2158 /*
2159  * create mixer controls
2160  *
2161  * walk through all UAC_OUTPUT_TERMINAL descriptors to search for mixers
2162  */
2163 static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
2164 {
2165         struct mixer_build state;
2166         int err;
2167         const struct usbmix_ctl_map *map;
2168         void *p;
2169
2170         memset(&state, 0, sizeof(state));
2171         state.chip = mixer->chip;
2172         state.mixer = mixer;
2173         state.buffer = mixer->hostif->extra;
2174         state.buflen = mixer->hostif->extralen;
2175
2176         /* check the mapping table */
2177         for (map = usbmix_ctl_maps; map->id; map++) {
2178                 if (map->id == state.chip->usb_id) {
2179                         state.map = map->map;
2180                         state.selector_map = map->selector_map;
2181                         mixer->ignore_ctl_error = map->ignore_ctl_error;
2182                         break;
2183                 }
2184         }
2185
2186         p = NULL;
2187         while ((p = snd_usb_find_csint_desc(mixer->hostif->extra,
2188                                             mixer->hostif->extralen,
2189                                             p, UAC_OUTPUT_TERMINAL)) != NULL) {
2190                 if (mixer->protocol == UAC_VERSION_1) {
2191                         struct uac1_output_terminal_descriptor *desc = p;
2192
2193                         if (desc->bLength < sizeof(*desc))
2194                                 continue; /* invalid descriptor? */
2195                         /* mark terminal ID as visited */
2196                         set_bit(desc->bTerminalID, state.unitbitmap);
2197                         state.oterm.id = desc->bTerminalID;
2198                         state.oterm.type = le16_to_cpu(desc->wTerminalType);
2199                         state.oterm.name = desc->iTerminal;
2200                         err = parse_audio_unit(&state, desc->bSourceID);
2201                         if (err < 0 && err != -EINVAL)
2202                                 return err;
2203                 } else { /* UAC_VERSION_2 */
2204                         struct uac2_output_terminal_descriptor *desc = p;
2205
2206                         if (desc->bLength < sizeof(*desc))
2207                                 continue; /* invalid descriptor? */
2208                         /* mark terminal ID as visited */
2209                         set_bit(desc->bTerminalID, state.unitbitmap);
2210                         state.oterm.id = desc->bTerminalID;
2211                         state.oterm.type = le16_to_cpu(desc->wTerminalType);
2212                         state.oterm.name = desc->iTerminal;
2213                         err = parse_audio_unit(&state, desc->bSourceID);
2214                         if (err < 0 && err != -EINVAL)
2215                                 return err;
2216
2217                         /*
2218                          * For UAC2, use the same approach to also add the
2219                          * clock selectors
2220                          */
2221                         err = parse_audio_unit(&state, desc->bCSourceID);
2222                         if (err < 0 && err != -EINVAL)
2223                                 return err;
2224                 }
2225         }
2226
2227         return 0;
2228 }
2229
2230 void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
2231 {
2232         struct usb_mixer_elem_list *list;
2233
2234         for (list = mixer->id_elems[unitid]; list; list = list->next_id_elem)
2235                 snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
2236                                &list->kctl->id);
2237 }
2238
2239 static void snd_usb_mixer_dump_cval(struct snd_info_buffer *buffer,
2240                                     struct usb_mixer_elem_list *list)
2241 {
2242         struct usb_mixer_elem_info *cval = (struct usb_mixer_elem_info *)list;
2243         static char *val_types[] = {"BOOLEAN", "INV_BOOLEAN",
2244                                     "S8", "U8", "S16", "U16"};
2245         snd_iprintf(buffer, "    Info: id=%i, control=%i, cmask=0x%x, "
2246                             "channels=%i, type=\"%s\"\n", cval->head.id,
2247                             cval->control, cval->cmask, cval->channels,
2248                             val_types[cval->val_type]);
2249         snd_iprintf(buffer, "    Volume: min=%i, max=%i, dBmin=%i, dBmax=%i\n",
2250                             cval->min, cval->max, cval->dBmin, cval->dBmax);
2251 }
2252
2253 static void snd_usb_mixer_proc_read(struct snd_info_entry *entry,
2254                                     struct snd_info_buffer *buffer)
2255 {
2256         struct snd_usb_audio *chip = entry->private_data;
2257         struct usb_mixer_interface *mixer;
2258         struct usb_mixer_elem_list *list;
2259         int unitid;
2260
2261         list_for_each_entry(mixer, &chip->mixer_list, list) {
2262                 snd_iprintf(buffer,
2263                         "USB Mixer: usb_id=0x%08x, ctrlif=%i, ctlerr=%i\n",
2264                                 chip->usb_id, snd_usb_ctrl_intf(chip),
2265                                 mixer->ignore_ctl_error);
2266                 snd_iprintf(buffer, "Card: %s\n", chip->card->longname);
2267                 for (unitid = 0; unitid < MAX_ID_ELEMS; unitid++) {
2268                         for (list = mixer->id_elems[unitid]; list;
2269                              list = list->next_id_elem) {
2270                                 snd_iprintf(buffer, "  Unit: %i\n", list->id);
2271                                 if (list->kctl)
2272                                         snd_iprintf(buffer,
2273                                                     "    Control: name=\"%s\", index=%i\n",
2274                                                     list->kctl->id.name,
2275                                                     list->kctl->id.index);
2276                                 if (list->dump)
2277                                         list->dump(buffer, list);
2278                         }
2279                 }
2280         }
2281 }
2282
2283 static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
2284                                        int attribute, int value, int index)
2285 {
2286         struct usb_mixer_elem_list *list;
2287         __u8 unitid = (index >> 8) & 0xff;
2288         __u8 control = (value >> 8) & 0xff;
2289         __u8 channel = value & 0xff;
2290
2291         if (channel >= MAX_CHANNELS) {
2292                 usb_audio_dbg(mixer->chip,
2293                         "%s(): bogus channel number %d\n",
2294                         __func__, channel);
2295                 return;
2296         }
2297
2298         for (list = mixer->id_elems[unitid]; list; list = list->next_id_elem) {
2299                 struct usb_mixer_elem_info *info;
2300
2301                 if (!list->kctl)
2302                         continue;
2303
2304                 info = (struct usb_mixer_elem_info *)list;
2305                 if (info->control != control)
2306                         continue;
2307
2308                 switch (attribute) {
2309                 case UAC2_CS_CUR:
2310                         /* invalidate cache, so the value is read from the device */
2311                         if (channel)
2312                                 info->cached &= ~(1 << channel);
2313                         else /* master channel */
2314                                 info->cached = 0;
2315
2316                         snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
2317                                        &info->head.kctl->id);
2318                         break;
2319
2320                 case UAC2_CS_RANGE:
2321                         /* TODO */
2322                         break;
2323
2324                 case UAC2_CS_MEM:
2325                         /* TODO */
2326                         break;
2327
2328                 default:
2329                         usb_audio_dbg(mixer->chip,
2330                                 "unknown attribute %d in interrupt\n",
2331                                 attribute);
2332                         break;
2333                 } /* switch */
2334         }
2335 }
2336
2337 static void snd_usb_mixer_interrupt(struct urb *urb)
2338 {
2339         struct usb_mixer_interface *mixer = urb->context;
2340         int len = urb->actual_length;
2341         int ustatus = urb->status;
2342
2343         if (ustatus != 0)
2344                 goto requeue;
2345
2346         if (mixer->protocol == UAC_VERSION_1) {
2347                 struct uac1_status_word *status;
2348
2349                 for (status = urb->transfer_buffer;
2350                      len >= sizeof(*status);
2351                      len -= sizeof(*status), status++) {
2352                         dev_dbg(&urb->dev->dev, "status interrupt: %02x %02x\n",
2353                                                 status->bStatusType,
2354                                                 status->bOriginator);
2355
2356                         /* ignore any notifications not from the control interface */
2357                         if ((status->bStatusType & UAC1_STATUS_TYPE_ORIG_MASK) !=
2358                                 UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF)
2359                                 continue;
2360
2361                         if (status->bStatusType & UAC1_STATUS_TYPE_MEM_CHANGED)
2362                                 snd_usb_mixer_rc_memory_change(mixer, status->bOriginator);
2363                         else
2364                                 snd_usb_mixer_notify_id(mixer, status->bOriginator);
2365                 }
2366         } else { /* UAC_VERSION_2 */
2367                 struct uac2_interrupt_data_msg *msg;
2368
2369                 for (msg = urb->transfer_buffer;
2370                      len >= sizeof(*msg);
2371                      len -= sizeof(*msg), msg++) {
2372                         /* drop vendor specific and endpoint requests */
2373                         if ((msg->bInfo & UAC2_INTERRUPT_DATA_MSG_VENDOR) ||
2374                             (msg->bInfo & UAC2_INTERRUPT_DATA_MSG_EP))
2375                                 continue;
2376
2377                         snd_usb_mixer_interrupt_v2(mixer, msg->bAttribute,
2378                                                    le16_to_cpu(msg->wValue),
2379                                                    le16_to_cpu(msg->wIndex));
2380                 }
2381         }
2382
2383 requeue:
2384         if (ustatus != -ENOENT &&
2385             ustatus != -ECONNRESET &&
2386             ustatus != -ESHUTDOWN) {
2387                 urb->dev = mixer->chip->dev;
2388                 usb_submit_urb(urb, GFP_ATOMIC);
2389         }
2390 }
2391
2392 /* create the handler for the optional status interrupt endpoint */
2393 static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer)
2394 {
2395         struct usb_endpoint_descriptor *ep;
2396         void *transfer_buffer;
2397         int buffer_length;
2398         unsigned int epnum;
2399
2400         /* we need one interrupt input endpoint */
2401         if (get_iface_desc(mixer->hostif)->bNumEndpoints < 1)
2402                 return 0;
2403         ep = get_endpoint(mixer->hostif, 0);
2404         if (!usb_endpoint_dir_in(ep) || !usb_endpoint_xfer_int(ep))
2405                 return 0;
2406
2407         epnum = usb_endpoint_num(ep);
2408         buffer_length = le16_to_cpu(ep->wMaxPacketSize);
2409         transfer_buffer = kmalloc(buffer_length, GFP_KERNEL);
2410         if (!transfer_buffer)
2411                 return -ENOMEM;
2412         mixer->urb = usb_alloc_urb(0, GFP_KERNEL);
2413         if (!mixer->urb) {
2414                 kfree(transfer_buffer);
2415                 return -ENOMEM;
2416         }
2417         usb_fill_int_urb(mixer->urb, mixer->chip->dev,
2418                          usb_rcvintpipe(mixer->chip->dev, epnum),
2419                          transfer_buffer, buffer_length,
2420                          snd_usb_mixer_interrupt, mixer, ep->bInterval);
2421         usb_submit_urb(mixer->urb, GFP_KERNEL);
2422         return 0;
2423 }
2424
2425 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
2426                          int ignore_error)
2427 {
2428         static struct snd_device_ops dev_ops = {
2429                 .dev_free = snd_usb_mixer_dev_free
2430         };
2431         struct usb_mixer_interface *mixer;
2432         struct snd_info_entry *entry;
2433         int err;
2434
2435         strcpy(chip->card->mixername, "USB Mixer");
2436
2437         mixer = kzalloc(sizeof(*mixer), GFP_KERNEL);
2438         if (!mixer)
2439                 return -ENOMEM;
2440         mixer->chip = chip;
2441         mixer->ignore_ctl_error = ignore_error;
2442         mixer->id_elems = kcalloc(MAX_ID_ELEMS, sizeof(*mixer->id_elems),
2443                                   GFP_KERNEL);
2444         if (!mixer->id_elems) {
2445                 kfree(mixer);
2446                 return -ENOMEM;
2447         }
2448
2449         mixer->hostif = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
2450         switch (get_iface_desc(mixer->hostif)->bInterfaceProtocol) {
2451         case UAC_VERSION_1:
2452         default:
2453                 mixer->protocol = UAC_VERSION_1;
2454                 break;
2455         case UAC_VERSION_2:
2456                 mixer->protocol = UAC_VERSION_2;
2457                 break;
2458         }
2459
2460         if ((err = snd_usb_mixer_controls(mixer)) < 0 ||
2461             (err = snd_usb_mixer_status_create(mixer)) < 0)
2462                 goto _error;
2463
2464         snd_usb_mixer_apply_create_quirk(mixer);
2465
2466         err = snd_device_new(chip->card, SNDRV_DEV_CODEC, mixer, &dev_ops);
2467         if (err < 0)
2468                 goto _error;
2469
2470         if (list_empty(&chip->mixer_list) &&
2471             !snd_card_proc_new(chip->card, "usbmixer", &entry))
2472                 snd_info_set_text_ops(entry, chip, snd_usb_mixer_proc_read);
2473
2474         list_add(&mixer->list, &chip->mixer_list);
2475         return 0;
2476
2477 _error:
2478         snd_usb_mixer_free(mixer);
2479         return err;
2480 }
2481
2482 void snd_usb_mixer_disconnect(struct usb_mixer_interface *mixer)
2483 {
2484         usb_kill_urb(mixer->urb);
2485         usb_kill_urb(mixer->rc_urb);
2486 }
2487
2488 #ifdef CONFIG_PM
2489 /* stop any bus activity of a mixer */
2490 static void snd_usb_mixer_inactivate(struct usb_mixer_interface *mixer)
2491 {
2492         usb_kill_urb(mixer->urb);
2493         usb_kill_urb(mixer->rc_urb);
2494 }
2495
2496 static int snd_usb_mixer_activate(struct usb_mixer_interface *mixer)
2497 {
2498         int err;
2499
2500         if (mixer->urb) {
2501                 err = usb_submit_urb(mixer->urb, GFP_NOIO);
2502                 if (err < 0)
2503                         return err;
2504         }
2505
2506         return 0;
2507 }
2508
2509 int snd_usb_mixer_suspend(struct usb_mixer_interface *mixer)
2510 {
2511         snd_usb_mixer_inactivate(mixer);
2512         return 0;
2513 }
2514
2515 static int restore_mixer_value(struct usb_mixer_elem_list *list)
2516 {
2517         struct usb_mixer_elem_info *cval = (struct usb_mixer_elem_info *)list;
2518         int c, err, idx;
2519
2520         if (cval->cmask) {
2521                 idx = 0;
2522                 for (c = 0; c < MAX_CHANNELS; c++) {
2523                         if (!(cval->cmask & (1 << c)))
2524                                 continue;
2525                         if (cval->cached & (1 << c)) {
2526                                 err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
2527                                                         cval->cache_val[idx]);
2528                                 if (err < 0)
2529                                         return err;
2530                         }
2531                         idx++;
2532                 }
2533         } else {
2534                 /* master */
2535                 if (cval->cached) {
2536                         err = snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
2537                         if (err < 0)
2538                                 return err;
2539                 }
2540         }
2541
2542         return 0;
2543 }
2544
2545 int snd_usb_mixer_resume(struct usb_mixer_interface *mixer, bool reset_resume)
2546 {
2547         struct usb_mixer_elem_list *list;
2548         int id, err;
2549
2550         if (reset_resume) {
2551                 /* restore cached mixer values */
2552                 for (id = 0; id < MAX_ID_ELEMS; id++) {
2553                         for (list = mixer->id_elems[id]; list;
2554                              list = list->next_id_elem) {
2555                                 if (list->resume) {
2556                                         err = list->resume(list);
2557                                         if (err < 0)
2558                                                 return err;
2559                                 }
2560                         }
2561                 }
2562         }
2563
2564         return snd_usb_mixer_activate(mixer);
2565 }
2566 #endif
2567
2568 void snd_usb_mixer_elem_init_std(struct usb_mixer_elem_list *list,
2569                                  struct usb_mixer_interface *mixer,
2570                                  int unitid)
2571 {
2572         list->mixer = mixer;
2573         list->id = unitid;
2574         list->dump = snd_usb_mixer_dump_cval;
2575 #ifdef CONFIG_PM
2576         list->resume = restore_mixer_value;
2577 #endif
2578 }