xref: /openbmc/linux/sound/usb/mixer_scarlett.c (revision f3539c12)
1 /*
2  *   Scarlett Driver for ALSA
3  *
4  *   Copyright (c) 2013 by Tobias Hoffmann
5  *   Copyright (c) 2013 by Robin Gareus <robin at gareus.org>
6  *   Copyright (c) 2002 by Takashi Iwai <tiwai at suse.de>
7  *   Copyright (c) 2014 by Chris J Arges <chris.j.arges at canonical.com>
8  *
9  *   Many codes borrowed from audio.c by
10  *	    Alan Cox (alan at lxorguk.ukuu.org.uk)
11  *	    Thomas Sailer (sailer at ife.ee.ethz.ch)
12  *
13  *   Code cleanup:
14  *   David Henningsson <david.henningsson at canonical.com>
15  *
16  *   This program is free software; you can redistribute it and/or modify
17  *   it under the terms of the GNU General Public License as published by
18  *   the Free Software Foundation; either version 2 of the License, or
19  *   (at your option) any later version.
20  *
21  *   This program is distributed in the hope that it will be useful,
22  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
23  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24  *   GNU General Public License for more details.
25  *
26  */
27 
28 /*
29  * Rewritten and extended to support more models, e.g. Scarlett 18i8.
30  *
31  * Auto-detection via UAC2 is not feasible to properly discover the vast
32  * majority of features. It's related to both Linux/ALSA's UAC2 as well as
33  * Focusrite's implementation of it. Eventually quirks may be sufficient but
34  * right now it's a major headache to work arount these things.
35  *
36  * NB. Neither the OSX nor the win driver provided by Focusrite performs
37  * discovery, they seem to operate the same as this driver.
38  */
39 
40 /* Mixer Interface for the Focusrite Scarlett 18i6 audio interface.
41  *
42  * The protocol was reverse engineered by looking at communication between
43  * Scarlett MixControl (v 1.2.128.0) and the Focusrite(R) Scarlett 18i6
44  * (firmware v305) using wireshark and usbmon in January 2013.
45  * Extended in July 2013.
46  *
47  * this mixer gives complete access to all features of the device:
48  *  - change Impedance of inputs (Line-in, Mic / Instrument, Hi-Z)
49  *  - select clock source
50  *  - dynamic input to mixer-matrix assignment
51  *  - 18 x 6 mixer-matrix gain stages
52  *  - bus routing & volume control
53  *  - automatic re-initialization on connect if device was power-cycled
54  *
55  * USB URB commands overview (bRequest = 0x01 = UAC2_CS_CUR)
56  * wIndex
57  * 0x01 Analog Input line/instrument impedance switch, wValue=0x0901 +
58  *      channel, data=Line/Inst (2bytes)
59  *      pad (-10dB) switch, wValue=0x0b01 + channel, data=Off/On (2bytes)
60  *      ?? wValue=0x0803/04, ?? (2bytes)
61  * 0x0a Master Volume, wValue=0x0200+bus[0:all + only 1..4?] data(2bytes)
62  *      Bus Mute/Unmute wValue=0x0100+bus[0:all + only 1..4?], data(2bytes)
63  * 0x28 Clock source, wValue=0x0100, data={1:int,2:spdif,3:adat} (1byte)
64  * 0x29 Set Sample-rate, wValue=0x0100, data=sample-rate(4bytes)
65  * 0x32 Mixer mux, wValue=0x0600 + mixer-channel, data=input-to-connect(2bytes)
66  * 0x33 Output mux, wValue=bus, data=input-to-connect(2bytes)
67  * 0x34 Capture mux, wValue=0...18, data=input-to-connect(2bytes)
68  * 0x3c Matrix Mixer gains, wValue=mixer-node  data=gain(2bytes)
69  *      ?? [sometimes](4bytes, e.g 0x000003be 0x000003bf ...03ff)
70  *
71  * USB reads: (i.e. actually issued by original software)
72  * 0x01 wValue=0x0901+channel (1byte!!), wValue=0x0b01+channed (1byte!!)
73  * 0x29 wValue=0x0100 sample-rate(4bytes)
74  *      wValue=0x0200 ?? 1byte (only once)
75  * 0x2a wValue=0x0100 ?? 4bytes, sample-rate2 ??
76  *
77  * USB reads with bRequest = 0x03 = UAC2_CS_MEM
78  * 0x3c wValue=0x0002 1byte: sync status (locked=1)
79  *      wValue=0x0000 18*2byte: peak meter (inputs)
80  *      wValue=0x0001 8(?)*2byte: peak meter (mix)
81  *      wValue=0x0003 6*2byte: peak meter (pcm/daw)
82  *
83  * USB write with bRequest = 0x03
84  * 0x3c Save settings to hardware: wValue=0x005a, data=0xa5
85  *
86  *
87  * <ditaa>
88  *  /--------------\    18chn            6chn    /--------------\
89  *  | Hardware  in +--+-------\        /------+--+ ALSA PCM out |
90  *  \--------------/  |       |        |      |  \--------------/
91  *                    |       |        |      |
92  *                    |       v        v      |
93  *                    |   +---------------+   |
94  *                    |    \ Matrix  Mux /    |
95  *                    |     +-----+-----+     |
96  *                    |           |           |
97  *                    |           | 18chn     |
98  *                    |           v           |
99  *                    |     +-----------+     |
100  *                    |     | Mixer     |     |
101  *                    |     |    Matrix |     |
102  *                    |     |           |     |
103  *                    |     | 18x6 Gain |     |
104  *                    |     |   stages  |     |
105  *                    |     +-----+-----+     |
106  *                    |           |           |
107  *                    |           |           |
108  *                    | 18chn     | 6chn      | 6chn
109  *                    v           v           v
110  *                    =========================
111  *             +---------------+     +--—------------+
112  *              \ Output  Mux /       \ Capture Mux /
113  *               +-----+-----+         +-----+-----+
114  *                     |                     |
115  *                     | 6chn                |
116  *                     v                     |
117  *              +-------------+              |
118  *              | Master Gain |              |
119  *              +------+------+              |
120  *                     |                     |
121  *                     | 6chn                | 18chn
122  *                     | (3 stereo pairs)    |
123  *  /--------------\   |                     |   /--------------\
124  *  | Hardware out |<--/                     \-->| ALSA PCM  in |
125  *  \--------------/                             \--------------/
126  * </ditaa>
127  *
128  */
129 
130 #include <linux/slab.h>
131 #include <linux/usb.h>
132 #include <linux/usb/audio-v2.h>
133 
134 #include <sound/core.h>
135 #include <sound/control.h>
136 #include <sound/tlv.h>
137 
138 #include "usbaudio.h"
139 #include "mixer.h"
140 #include "helper.h"
141 #include "power.h"
142 
143 #include "mixer_scarlett.h"
144 
145 /* some gui mixers can't handle negative ctl values */
146 #define SND_SCARLETT_LEVEL_BIAS 128
147 #define SND_SCARLETT_MATRIX_IN_MAX 18
148 #define SND_SCARLETT_CONTROLS_MAX 10
149 #define SND_SCARLETT_OFFSETS_MAX 5
150 
151 enum {
152 	SCARLETT_OUTPUTS,
153 	SCARLETT_SWITCH_IMPEDANCE,
154 	SCARLETT_SWITCH_PAD,
155 };
156 
157 enum {
158 	SCARLETT_OFFSET_PCM = 0,
159 	SCARLETT_OFFSET_ANALOG = 1,
160 	SCARLETT_OFFSET_SPDIF = 2,
161 	SCARLETT_OFFSET_ADAT = 3,
162 	SCARLETT_OFFSET_MIX = 4,
163 };
164 
165 struct scarlett_mixer_elem_enum_info {
166 	int start;
167 	int len;
168 	int offsets[SND_SCARLETT_OFFSETS_MAX];
169 	char const * const *names;
170 };
171 
172 struct scarlett_mixer_control {
173 	unsigned char num;
174 	unsigned char type;
175 	const char *name;
176 };
177 
178 struct scarlett_device_info {
179 	int matrix_in;
180 	int matrix_out;
181 	int input_len;
182 	int output_len;
183 
184 	struct scarlett_mixer_elem_enum_info opt_master;
185 	struct scarlett_mixer_elem_enum_info opt_matrix;
186 
187 	/* initial values for matrix mux */
188 	int matrix_mux_init[SND_SCARLETT_MATRIX_IN_MAX];
189 
190 	int num_controls;	/* number of items in controls */
191 	const struct scarlett_mixer_control controls[SND_SCARLETT_CONTROLS_MAX];
192 };
193 
194 /********************** Enum Strings *************************/
195 
196 static const struct scarlett_mixer_elem_enum_info opt_pad = {
197 	.start = 0,
198 	.len = 2,
199 	.offsets = {},
200 	.names = (char const * const []){
201 		"0dB", "-10dB"
202 	}
203 };
204 
205 static const struct scarlett_mixer_elem_enum_info opt_impedance = {
206 	.start = 0,
207 	.len = 2,
208 	.offsets = {},
209 	.names = (char const * const []){
210 		"Line", "Hi-Z"
211 	}
212 };
213 
214 static const struct scarlett_mixer_elem_enum_info opt_clock = {
215 	.start = 1,
216 	.len = 3,
217 	.offsets = {},
218 	.names = (char const * const []){
219 		"Internal", "SPDIF", "ADAT"
220 	}
221 };
222 
223 static const struct scarlett_mixer_elem_enum_info opt_sync = {
224 	.start = 0,
225 	.len = 2,
226 	.offsets = {},
227 	.names = (char const * const []){
228 		"No Lock", "Locked"
229 	}
230 };
231 
232 static int scarlett_ctl_switch_info(struct snd_kcontrol *kctl,
233 		struct snd_ctl_elem_info *uinfo)
234 {
235 	struct usb_mixer_elem_info *elem = kctl->private_data;
236 
237 	uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
238 	uinfo->count = elem->channels;
239 	uinfo->value.integer.min = 0;
240 	uinfo->value.integer.max = 1;
241 	return 0;
242 }
243 
244 static int scarlett_ctl_switch_get(struct snd_kcontrol *kctl,
245 		struct snd_ctl_elem_value *ucontrol)
246 {
247 	struct usb_mixer_elem_info *elem = kctl->private_data;
248 	int i, err, val;
249 
250 	for (i = 0; i < elem->channels; i++) {
251 		err = snd_usb_get_cur_mix_value(elem, i, i, &val);
252 		if (err < 0)
253 			return err;
254 
255 		val = !val; /* invert mute logic for mixer */
256 		ucontrol->value.integer.value[i] = val;
257 	}
258 
259 	return 0;
260 }
261 
262 static int scarlett_ctl_switch_put(struct snd_kcontrol *kctl,
263 		struct snd_ctl_elem_value *ucontrol)
264 {
265 	struct usb_mixer_elem_info *elem = kctl->private_data;
266 	int i, changed = 0;
267 	int err, oval, val;
268 
269 	for (i = 0; i < elem->channels; i++) {
270 		err = snd_usb_get_cur_mix_value(elem, i, i, &oval);
271 		if (err < 0)
272 			return err;
273 
274 		val = ucontrol->value.integer.value[i];
275 		val = !val;
276 		if (oval != val) {
277 			err = snd_usb_set_cur_mix_value(elem, i, i, val);
278 			if (err < 0)
279 				return err;
280 
281 			changed = 1;
282 		}
283 	}
284 
285 	return changed;
286 }
287 
288 static int scarlett_ctl_resume(struct usb_mixer_elem_list *list)
289 {
290 	struct usb_mixer_elem_info *elem =
291 		container_of(list, struct usb_mixer_elem_info, head);
292 	int i;
293 
294 	for (i = 0; i < elem->channels; i++)
295 		if (elem->cached & (1 << i))
296 			snd_usb_set_cur_mix_value(elem, i, i,
297 						  elem->cache_val[i]);
298 	return 0;
299 }
300 
301 static int scarlett_ctl_info(struct snd_kcontrol *kctl,
302 			     struct snd_ctl_elem_info *uinfo)
303 {
304 	struct usb_mixer_elem_info *elem = kctl->private_data;
305 
306 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
307 	uinfo->count = elem->channels;
308 	uinfo->value.integer.min = 0;
309 	uinfo->value.integer.max = (int)kctl->private_value +
310 		SND_SCARLETT_LEVEL_BIAS;
311 	uinfo->value.integer.step = 1;
312 	return 0;
313 }
314 
315 static int scarlett_ctl_get(struct snd_kcontrol *kctl,
316 			    struct snd_ctl_elem_value *ucontrol)
317 {
318 	struct usb_mixer_elem_info *elem = kctl->private_data;
319 	int i, err, val;
320 
321 	for (i = 0; i < elem->channels; i++) {
322 		err = snd_usb_get_cur_mix_value(elem, i, i, &val);
323 		if (err < 0)
324 			return err;
325 
326 		val = clamp(val / 256, -128, (int)kctl->private_value) +
327 				    SND_SCARLETT_LEVEL_BIAS;
328 		ucontrol->value.integer.value[i] = val;
329 	}
330 
331 	return 0;
332 }
333 
334 static int scarlett_ctl_put(struct snd_kcontrol *kctl,
335 			    struct snd_ctl_elem_value *ucontrol)
336 {
337 	struct usb_mixer_elem_info *elem = kctl->private_data;
338 	int i, changed = 0;
339 	int err, oval, val;
340 
341 	for (i = 0; i < elem->channels; i++) {
342 		err = snd_usb_get_cur_mix_value(elem, i, i, &oval);
343 		if (err < 0)
344 			return err;
345 
346 		val = ucontrol->value.integer.value[i] -
347 			SND_SCARLETT_LEVEL_BIAS;
348 		val = val * 256;
349 		if (oval != val) {
350 			err = snd_usb_set_cur_mix_value(elem, i, i, val);
351 			if (err < 0)
352 				return err;
353 
354 			changed = 1;
355 		}
356 	}
357 
358 	return changed;
359 }
360 
361 static void scarlett_generate_name(int i, char *dst, int offsets[])
362 {
363 	if (i > offsets[SCARLETT_OFFSET_MIX])
364 		sprintf(dst, "Mix %c",
365 			'A'+(i - offsets[SCARLETT_OFFSET_MIX] - 1));
366 	else if (i > offsets[SCARLETT_OFFSET_ADAT])
367 		sprintf(dst, "ADAT %d", i - offsets[SCARLETT_OFFSET_ADAT]);
368 	else if (i > offsets[SCARLETT_OFFSET_SPDIF])
369 		sprintf(dst, "SPDIF %d", i - offsets[SCARLETT_OFFSET_SPDIF]);
370 	else if (i > offsets[SCARLETT_OFFSET_ANALOG])
371 		sprintf(dst, "Analog %d", i - offsets[SCARLETT_OFFSET_ANALOG]);
372 	else if (i > offsets[SCARLETT_OFFSET_PCM])
373 		sprintf(dst, "PCM %d", i - offsets[SCARLETT_OFFSET_PCM]);
374 	else
375 		sprintf(dst, "Off");
376 }
377 
378 static int scarlett_ctl_enum_dynamic_info(struct snd_kcontrol *kctl,
379 					  struct snd_ctl_elem_info *uinfo)
380 {
381 	struct usb_mixer_elem_info *elem = kctl->private_data;
382 	struct scarlett_mixer_elem_enum_info *opt = elem->private_data;
383 	unsigned int items = opt->len;
384 
385 	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
386 	uinfo->count = elem->channels;
387 	uinfo->value.enumerated.items = items;
388 
389 	if (uinfo->value.enumerated.item >= items)
390 		uinfo->value.enumerated.item = items - 1;
391 
392 	/* generate name dynamically based on item number and offset info */
393 	scarlett_generate_name(uinfo->value.enumerated.item,
394 			       uinfo->value.enumerated.name,
395 			       opt->offsets);
396 
397 	return 0;
398 }
399 
400 static int scarlett_ctl_enum_info(struct snd_kcontrol *kctl,
401 				  struct snd_ctl_elem_info *uinfo)
402 {
403 	struct usb_mixer_elem_info *elem = kctl->private_data;
404 	struct scarlett_mixer_elem_enum_info *opt = elem->private_data;
405 
406 	return snd_ctl_enum_info(uinfo, elem->channels, opt->len,
407 				 (const char * const *)opt->names);
408 }
409 
410 static int scarlett_ctl_enum_get(struct snd_kcontrol *kctl,
411 				 struct snd_ctl_elem_value *ucontrol)
412 {
413 	struct usb_mixer_elem_info *elem = kctl->private_data;
414 	struct scarlett_mixer_elem_enum_info *opt = elem->private_data;
415 	int err, val;
416 
417 	err = snd_usb_get_cur_mix_value(elem, 0, 0, &val);
418 	if (err < 0)
419 		return err;
420 
421 	val = clamp(val - opt->start, 0, opt->len-1);
422 
423 	ucontrol->value.enumerated.item[0] = val;
424 
425 	return 0;
426 }
427 
428 static int scarlett_ctl_enum_put(struct snd_kcontrol *kctl,
429 				 struct snd_ctl_elem_value *ucontrol)
430 {
431 	struct usb_mixer_elem_info *elem = kctl->private_data;
432 	struct scarlett_mixer_elem_enum_info *opt = elem->private_data;
433 	int err, oval, val;
434 
435 	err = snd_usb_get_cur_mix_value(elem, 0, 0, &oval);
436 	if (err < 0)
437 		return err;
438 
439 	val = ucontrol->value.integer.value[0];
440 	val = val + opt->start;
441 	if (val != oval) {
442 		snd_usb_set_cur_mix_value(elem, 0, 0, val);
443 		return 1;
444 	}
445 	return 0;
446 }
447 
448 static int scarlett_ctl_enum_resume(struct usb_mixer_elem_list *list)
449 {
450 	struct usb_mixer_elem_info *elem =
451 		container_of(list, struct usb_mixer_elem_info, head);
452 
453 	if (elem->cached)
454 		snd_usb_set_cur_mix_value(elem, 0, 0, *elem->cache_val);
455 	return 0;
456 }
457 
458 static int scarlett_ctl_meter_get(struct snd_kcontrol *kctl,
459 				  struct snd_ctl_elem_value *ucontrol)
460 {
461 	struct usb_mixer_elem_info *elem = kctl->private_data;
462 	struct snd_usb_audio *chip = elem->head.mixer->chip;
463 	unsigned char buf[2 * MAX_CHANNELS] = {0, };
464 	int wValue = (elem->control << 8) | elem->idx_off;
465 	int idx = snd_usb_ctrl_intf(chip) | (elem->head.id << 8);
466 	int err;
467 
468 	err = snd_usb_ctl_msg(chip->dev,
469 				usb_rcvctrlpipe(chip->dev, 0),
470 				UAC2_CS_MEM,
471 				USB_RECIP_INTERFACE | USB_TYPE_CLASS |
472 				USB_DIR_IN, wValue, idx, buf, elem->channels);
473 	if (err < 0)
474 		return err;
475 
476 	ucontrol->value.enumerated.item[0] = clamp((int)buf[0], 0, 1);
477 	return 0;
478 }
479 
480 static struct snd_kcontrol_new usb_scarlett_ctl_switch = {
481 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
482 	.name = "",
483 	.info = scarlett_ctl_switch_info,
484 	.get =  scarlett_ctl_switch_get,
485 	.put =  scarlett_ctl_switch_put,
486 };
487 
488 static const DECLARE_TLV_DB_SCALE(db_scale_scarlett_gain, -12800, 100, 0);
489 
490 static struct snd_kcontrol_new usb_scarlett_ctl = {
491 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
492 	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
493 		  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
494 	.name = "",
495 	.info = scarlett_ctl_info,
496 	.get =  scarlett_ctl_get,
497 	.put =  scarlett_ctl_put,
498 	.private_value = 6,  /* max value */
499 	.tlv = { .p = db_scale_scarlett_gain }
500 };
501 
502 static struct snd_kcontrol_new usb_scarlett_ctl_master = {
503 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
504 	.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
505 		  SNDRV_CTL_ELEM_ACCESS_TLV_READ,
506 	.name = "",
507 	.info = scarlett_ctl_info,
508 	.get =  scarlett_ctl_get,
509 	.put =  scarlett_ctl_put,
510 	.private_value = 6,  /* max value */
511 	.tlv = { .p = db_scale_scarlett_gain }
512 };
513 
514 static struct snd_kcontrol_new usb_scarlett_ctl_enum = {
515 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
516 	.name = "",
517 	.info = scarlett_ctl_enum_info,
518 	.get =  scarlett_ctl_enum_get,
519 	.put =  scarlett_ctl_enum_put,
520 };
521 
522 static struct snd_kcontrol_new usb_scarlett_ctl_dynamic_enum = {
523 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
524 	.name = "",
525 	.info = scarlett_ctl_enum_dynamic_info,
526 	.get =  scarlett_ctl_enum_get,
527 	.put =  scarlett_ctl_enum_put,
528 };
529 
530 static struct snd_kcontrol_new usb_scarlett_ctl_sync = {
531 	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
532 	.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
533 	.name = "",
534 	.info = scarlett_ctl_enum_info,
535 	.get =  scarlett_ctl_meter_get,
536 };
537 
538 static int add_new_ctl(struct usb_mixer_interface *mixer,
539 		       const struct snd_kcontrol_new *ncontrol,
540 		       usb_mixer_elem_resume_func_t resume,
541 		       int index, int offset, int num,
542 		       int val_type, int channels, const char *name,
543 		       const struct scarlett_mixer_elem_enum_info *opt,
544 		       struct usb_mixer_elem_info **elem_ret
545 )
546 {
547 	struct snd_kcontrol *kctl;
548 	struct usb_mixer_elem_info *elem;
549 	int err;
550 
551 	elem = kzalloc(sizeof(*elem), GFP_KERNEL);
552 	if (!elem)
553 		return -ENOMEM;
554 
555 	elem->head.mixer = mixer;
556 	elem->head.resume = resume;
557 	elem->control = offset;
558 	elem->idx_off = num;
559 	elem->head.id = index;
560 	elem->val_type = val_type;
561 
562 	elem->channels = channels;
563 
564 	/* add scarlett_mixer_elem_enum_info struct */
565 	elem->private_data = (void *)opt;
566 
567 	kctl = snd_ctl_new1(ncontrol, elem);
568 	if (!kctl) {
569 		kfree(elem);
570 		return -ENOMEM;
571 	}
572 	kctl->private_free = snd_usb_mixer_elem_free;
573 
574 	strlcpy(kctl->id.name, name, sizeof(kctl->id.name));
575 
576 	err = snd_usb_mixer_add_control(&elem->head, kctl);
577 	if (err < 0)
578 		return err;
579 
580 	if (elem_ret)
581 		*elem_ret = elem;
582 
583 	return 0;
584 }
585 
586 static int add_output_ctls(struct usb_mixer_interface *mixer,
587 			   int index, const char *name,
588 			   const struct scarlett_device_info *info)
589 {
590 	int err;
591 	char mx[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
592 	struct usb_mixer_elem_info *elem;
593 
594 	/* Add mute switch */
595 	snprintf(mx, sizeof(mx), "Master %d (%s) Playback Switch",
596 		index + 1, name);
597 	err = add_new_ctl(mixer, &usb_scarlett_ctl_switch,
598 			  scarlett_ctl_resume, 0x0a, 0x01,
599 			  2*index+1, USB_MIXER_S16, 2, mx, NULL, &elem);
600 	if (err < 0)
601 		return err;
602 
603 	/* Add volume control and initialize to 0 */
604 	snprintf(mx, sizeof(mx), "Master %d (%s) Playback Volume",
605 		index + 1, name);
606 	err = add_new_ctl(mixer, &usb_scarlett_ctl_master,
607 			  scarlett_ctl_resume, 0x0a, 0x02,
608 			  2*index+1, USB_MIXER_S16, 2, mx, NULL, &elem);
609 	if (err < 0)
610 		return err;
611 
612 	/* Add L channel source playback enumeration */
613 	snprintf(mx, sizeof(mx), "Master %dL (%s) Source Playback Enum",
614 		index + 1, name);
615 	err = add_new_ctl(mixer, &usb_scarlett_ctl_dynamic_enum,
616 			  scarlett_ctl_enum_resume, 0x33, 0x00,
617 			  2*index, USB_MIXER_S16, 1, mx, &info->opt_master,
618 			  &elem);
619 	if (err < 0)
620 		return err;
621 
622 	/* Add R channel source playback enumeration */
623 	snprintf(mx, sizeof(mx), "Master %dR (%s) Source Playback Enum",
624 		index + 1, name);
625 	err = add_new_ctl(mixer, &usb_scarlett_ctl_dynamic_enum,
626 			  scarlett_ctl_enum_resume, 0x33, 0x00,
627 			  2*index+1, USB_MIXER_S16, 1, mx, &info->opt_master,
628 			  &elem);
629 	if (err < 0)
630 		return err;
631 
632 	return 0;
633 }
634 
635 /********************** device-specific config *************************/
636 
637 /*  untested...  */
638 static struct scarlett_device_info s6i6_info = {
639 	.matrix_in = 18,
640 	.matrix_out = 8,
641 	.input_len = 6,
642 	.output_len = 6,
643 
644 	.opt_master = {
645 		.start = -1,
646 		.len = 27,
647 		.offsets = {0, 12, 16, 18, 18},
648 		.names = NULL
649 	},
650 
651 	.opt_matrix = {
652 		.start = -1,
653 		.len = 19,
654 		.offsets = {0, 12, 16, 18, 18},
655 		.names = NULL
656 	},
657 
658 	.num_controls = 9,
659 	.controls = {
660 		{ .num = 0, .type = SCARLETT_OUTPUTS, .name = "Monitor" },
661 		{ .num = 1, .type = SCARLETT_OUTPUTS, .name = "Headphone" },
662 		{ .num = 2, .type = SCARLETT_OUTPUTS, .name = "SPDIF" },
663 		{ .num = 1, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
664 		{ .num = 1, .type = SCARLETT_SWITCH_PAD, .name = NULL},
665 		{ .num = 2, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
666 		{ .num = 2, .type = SCARLETT_SWITCH_PAD, .name = NULL},
667 		{ .num = 3, .type = SCARLETT_SWITCH_PAD, .name = NULL},
668 		{ .num = 4, .type = SCARLETT_SWITCH_PAD, .name = NULL},
669 	},
670 
671 	.matrix_mux_init = {
672 		12, 13, 14, 15,                 /* Analog -> 1..4 */
673 		16, 17,                          /* SPDIF -> 5,6 */
674 		0, 1, 2, 3, 4, 5, 6, 7,     /* PCM[1..12] -> 7..18 */
675 		8, 9, 10, 11
676 	}
677 };
678 
679 /*  untested...  */
680 static struct scarlett_device_info s8i6_info = {
681 	.matrix_in = 18,
682 	.matrix_out = 6,
683 	.input_len = 8,
684 	.output_len = 6,
685 
686 	.opt_master = {
687 		.start = -1,
688 		.len = 25,
689 		.offsets = {0, 12, 16, 18, 18},
690 		.names = NULL
691 	},
692 
693 	.opt_matrix = {
694 		.start = -1,
695 		.len = 19,
696 		.offsets = {0, 12, 16, 18, 18},
697 		.names = NULL
698 	},
699 
700 	.num_controls = 7,
701 	.controls = {
702 		{ .num = 0, .type = SCARLETT_OUTPUTS, .name = "Monitor" },
703 		{ .num = 1, .type = SCARLETT_OUTPUTS, .name = "Headphone" },
704 		{ .num = 2, .type = SCARLETT_OUTPUTS, .name = "SPDIF" },
705 		{ .num = 1, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
706 		{ .num = 2, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
707 		{ .num = 3, .type = SCARLETT_SWITCH_PAD, .name = NULL},
708 		{ .num = 4, .type = SCARLETT_SWITCH_PAD, .name = NULL},
709 	},
710 
711 	.matrix_mux_init = {
712 		12, 13, 14, 15,                 /* Analog -> 1..4 */
713 		16, 17,                          /* SPDIF -> 5,6 */
714 		0, 1, 2, 3, 4, 5, 6, 7,     /* PCM[1..12] -> 7..18 */
715 		8, 9, 10, 11
716 	}
717 };
718 
719 static struct scarlett_device_info s18i6_info = {
720 	.matrix_in = 18,
721 	.matrix_out = 6,
722 	.input_len = 18,
723 	.output_len = 6,
724 
725 	.opt_master = {
726 		.start = -1,
727 		.len = 31,
728 		.offsets = {0, 6, 14, 16, 24},
729 		.names = NULL,
730 	},
731 
732 	.opt_matrix = {
733 		.start = -1,
734 		.len = 25,
735 		.offsets = {0, 6, 14, 16, 24},
736 		.names = NULL,
737 	},
738 
739 	.num_controls = 5,
740 	.controls = {
741 		{ .num = 0, .type = SCARLETT_OUTPUTS, .name = "Monitor" },
742 		{ .num = 1, .type = SCARLETT_OUTPUTS, .name = "Headphone" },
743 		{ .num = 2, .type = SCARLETT_OUTPUTS, .name = "SPDIF" },
744 		{ .num = 1, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
745 		{ .num = 2, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
746 	},
747 
748 	.matrix_mux_init = {
749 		 6,  7,  8,  9, 10, 11, 12, 13, /* Analog -> 1..8 */
750 		16, 17, 18, 19, 20, 21,     /* ADAT[1..6] -> 9..14 */
751 		14, 15,                          /* SPDIF -> 15,16 */
752 		0, 1                          /* PCM[1,2] -> 17,18 */
753 	}
754 };
755 
756 static struct scarlett_device_info s18i8_info = {
757 	.matrix_in = 18,
758 	.matrix_out = 8,
759 	.input_len = 18,
760 	.output_len = 8,
761 
762 	.opt_master = {
763 		.start = -1,
764 		.len = 35,
765 		.offsets = {0, 8, 16, 18, 26},
766 		.names = NULL
767 	},
768 
769 	.opt_matrix = {
770 		.start = -1,
771 		.len = 27,
772 		.offsets = {0, 8, 16, 18, 26},
773 		.names = NULL
774 	},
775 
776 	.num_controls = 10,
777 	.controls = {
778 		{ .num = 0, .type = SCARLETT_OUTPUTS, .name = "Monitor" },
779 		{ .num = 1, .type = SCARLETT_OUTPUTS, .name = "Headphone 1" },
780 		{ .num = 2, .type = SCARLETT_OUTPUTS, .name = "Headphone 2" },
781 		{ .num = 3, .type = SCARLETT_OUTPUTS, .name = "SPDIF" },
782 		{ .num = 1, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
783 		{ .num = 1, .type = SCARLETT_SWITCH_PAD, .name = NULL},
784 		{ .num = 2, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
785 		{ .num = 2, .type = SCARLETT_SWITCH_PAD, .name = NULL},
786 		{ .num = 3, .type = SCARLETT_SWITCH_PAD, .name = NULL},
787 		{ .num = 4, .type = SCARLETT_SWITCH_PAD, .name = NULL},
788 	},
789 
790 	.matrix_mux_init = {
791 		 8,  9, 10, 11, 12, 13, 14, 15, /* Analog -> 1..8 */
792 		18, 19, 20, 21, 22, 23,     /* ADAT[1..6] -> 9..14 */
793 		16, 17,                          /* SPDIF -> 15,16 */
794 		0, 1                          /* PCM[1,2] -> 17,18 */
795 	}
796 };
797 
798 static struct scarlett_device_info s18i20_info = {
799 	.matrix_in = 18,
800 	.matrix_out = 8,
801 	.input_len = 18,
802 	.output_len = 20,
803 
804 	.opt_master = {
805 		.start = -1,
806 		.len = 47,
807 		.offsets = {0, 20, 28, 30, 38},
808 		.names = NULL
809 	},
810 
811 	.opt_matrix = {
812 		.start = -1,
813 		.len = 39,
814 		.offsets = {0, 20, 28, 30, 38},
815 		.names = NULL
816 	},
817 
818 	.num_controls = 10,
819 	.controls = {
820 		{ .num = 0, .type = SCARLETT_OUTPUTS, .name = "Monitor" },
821 		{ .num = 1, .type = SCARLETT_OUTPUTS, .name = "Line 3/4" },
822 		{ .num = 2, .type = SCARLETT_OUTPUTS, .name = "Line 5/6" },
823 		{ .num = 3, .type = SCARLETT_OUTPUTS, .name = "Line 7/8" },
824 		{ .num = 4, .type = SCARLETT_OUTPUTS, .name = "Line 9/10" },
825 		{ .num = 5, .type = SCARLETT_OUTPUTS, .name = "SPDIF" },
826 		{ .num = 6, .type = SCARLETT_OUTPUTS, .name = "ADAT 1/2" },
827 		{ .num = 7, .type = SCARLETT_OUTPUTS, .name = "ADAT 3/4" },
828 		{ .num = 8, .type = SCARLETT_OUTPUTS, .name = "ADAT 5/6" },
829 		{ .num = 9, .type = SCARLETT_OUTPUTS, .name = "ADAT 7/8" },
830 		/*{ .num = 1, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
831 		{ .num = 1, .type = SCARLETT_SWITCH_PAD, .name = NULL},
832 		{ .num = 2, .type = SCARLETT_SWITCH_IMPEDANCE, .name = NULL},
833 		{ .num = 2, .type = SCARLETT_SWITCH_PAD, .name = NULL},
834 		{ .num = 3, .type = SCARLETT_SWITCH_PAD, .name = NULL},
835 		{ .num = 4, .type = SCARLETT_SWITCH_PAD, .name = NULL},*/
836 	},
837 
838 	.matrix_mux_init = {
839 		20, 21, 22, 23, 24, 25, 26, 27, /* Analog -> 1..8 */
840 		30, 31, 32, 33, 34, 35,     /* ADAT[1..6] -> 9..14 */
841 		28, 29,                          /* SPDIF -> 15,16 */
842 		0, 1                          /* PCM[1,2] -> 17,18 */
843 	}
844 };
845 
846 
847 static int scarlett_controls_create_generic(struct usb_mixer_interface *mixer,
848 	struct scarlett_device_info *info)
849 {
850 	int i, err;
851 	char mx[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
852 	const struct scarlett_mixer_control *ctl;
853 	struct usb_mixer_elem_info *elem;
854 
855 	/* create master switch and playback volume */
856 	err = add_new_ctl(mixer, &usb_scarlett_ctl_switch,
857 			  scarlett_ctl_resume, 0x0a, 0x01, 0,
858 			  USB_MIXER_S16, 1, "Master Playback Switch", NULL,
859 			  &elem);
860 	if (err < 0)
861 		return err;
862 
863 	err = add_new_ctl(mixer, &usb_scarlett_ctl_master,
864 			  scarlett_ctl_resume, 0x0a, 0x02, 0,
865 			  USB_MIXER_S16, 1, "Master Playback Volume", NULL,
866 			  &elem);
867 	if (err < 0)
868 		return err;
869 
870 	/* iterate through controls in info struct and create each one */
871 	for (i = 0; i < info->num_controls; i++) {
872 		ctl = &info->controls[i];
873 
874 		switch (ctl->type) {
875 		case SCARLETT_OUTPUTS:
876 			err = add_output_ctls(mixer, ctl->num, ctl->name, info);
877 			if (err < 0)
878 				return err;
879 			break;
880 		case SCARLETT_SWITCH_IMPEDANCE:
881 			sprintf(mx, "Input %d Impedance Switch", ctl->num);
882 			err = add_new_ctl(mixer, &usb_scarlett_ctl_enum,
883 					  scarlett_ctl_enum_resume, 0x01,
884 					  0x09, ctl->num, USB_MIXER_S16, 1, mx,
885 					  &opt_impedance, &elem);
886 			if (err < 0)
887 				return err;
888 			break;
889 		case SCARLETT_SWITCH_PAD:
890 			sprintf(mx, "Input %d Pad Switch", ctl->num);
891 			err = add_new_ctl(mixer, &usb_scarlett_ctl_enum,
892 					  scarlett_ctl_enum_resume, 0x01,
893 					  0x0b, ctl->num, USB_MIXER_S16, 1, mx,
894 					  &opt_pad, &elem);
895 			if (err < 0)
896 				return err;
897 			break;
898 		}
899 	}
900 
901 	return 0;
902 }
903 
904 /*
905  * Create and initialize a mixer for the Focusrite(R) Scarlett
906  */
907 int snd_scarlett_controls_create(struct usb_mixer_interface *mixer)
908 {
909 	int err, i, o;
910 	char mx[SNDRV_CTL_ELEM_ID_NAME_MAXLEN];
911 	struct scarlett_device_info *info;
912 	struct usb_mixer_elem_info *elem;
913 	static char sample_rate_buffer[4] = { '\x80', '\xbb', '\x00', '\x00' };
914 
915 	/* only use UAC_VERSION_2 */
916 	if (!mixer->protocol)
917 		return 0;
918 
919 	switch (mixer->chip->usb_id) {
920 	case USB_ID(0x1235, 0x8012):
921 		info = &s6i6_info;
922 		break;
923 	case USB_ID(0x1235, 0x8002):
924 		info = &s8i6_info;
925 		break;
926 	case USB_ID(0x1235, 0x8004):
927 		info = &s18i6_info;
928 		break;
929 	case USB_ID(0x1235, 0x8014):
930 		info = &s18i8_info;
931 		break;
932 	case USB_ID(0x1235, 0x800c):
933 		info = &s18i20_info;
934 		break;
935 	default: /* device not (yet) supported */
936 		return -EINVAL;
937 	}
938 
939 	/* generic function to create controls */
940 	err = scarlett_controls_create_generic(mixer, info);
941 	if (err < 0)
942 		return err;
943 
944 	/* setup matrix controls */
945 	for (i = 0; i < info->matrix_in; i++) {
946 		snprintf(mx, sizeof(mx), "Matrix %02d Input Playback Route",
947 			 i+1);
948 		err = add_new_ctl(mixer, &usb_scarlett_ctl_dynamic_enum,
949 				  scarlett_ctl_enum_resume, 0x32,
950 				  0x06, i, USB_MIXER_S16, 1, mx,
951 				  &info->opt_matrix, &elem);
952 		if (err < 0)
953 			return err;
954 
955 		for (o = 0; o < info->matrix_out; o++) {
956 			sprintf(mx, "Matrix %02d Mix %c Playback Volume", i+1,
957 				o+'A');
958 			err = add_new_ctl(mixer, &usb_scarlett_ctl,
959 					  scarlett_ctl_resume, 0x3c, 0x00,
960 					  (i << 3) + (o & 0x07), USB_MIXER_S16,
961 					  1, mx, NULL, &elem);
962 			if (err < 0)
963 				return err;
964 
965 		}
966 	}
967 
968 	for (i = 0; i < info->input_len; i++) {
969 		snprintf(mx, sizeof(mx), "Input Source %02d Capture Route",
970 			 i+1);
971 		err = add_new_ctl(mixer, &usb_scarlett_ctl_dynamic_enum,
972 				  scarlett_ctl_enum_resume, 0x34,
973 				  0x00, i, USB_MIXER_S16, 1, mx,
974 				  &info->opt_master, &elem);
975 		if (err < 0)
976 			return err;
977 	}
978 
979 	/* val_len == 1 needed here */
980 	err = add_new_ctl(mixer, &usb_scarlett_ctl_enum,
981 			  scarlett_ctl_enum_resume, 0x28, 0x01, 0,
982 			  USB_MIXER_U8, 1, "Sample Clock Source",
983 			  &opt_clock, &elem);
984 	if (err < 0)
985 		return err;
986 
987 	/* val_len == 1 and UAC2_CS_MEM */
988 	err = add_new_ctl(mixer, &usb_scarlett_ctl_sync, NULL, 0x3c, 0x00, 2,
989 			  USB_MIXER_U8, 1, "Sample Clock Sync Status",
990 			  &opt_sync, &elem);
991 	if (err < 0)
992 		return err;
993 
994 	/* initialize sampling rate to 48000 */
995 	err = snd_usb_ctl_msg(mixer->chip->dev,
996 		usb_sndctrlpipe(mixer->chip->dev, 0), UAC2_CS_CUR,
997 		USB_RECIP_INTERFACE | USB_TYPE_CLASS |
998 		USB_DIR_OUT, 0x0100, snd_usb_ctrl_intf(mixer->chip) |
999 		(0x29 << 8), sample_rate_buffer, 4);
1000 	if (err < 0)
1001 		return err;
1002 
1003 	return err;
1004 }
1005