xref: /linux/sound/usb/6fire/control.c (revision 2a2c74b2efcb1a0ca3fdcb5fbb96ad8de6a29177)
1 /*
2  * Linux driver for TerraTec DMX 6Fire USB
3  *
4  * Mixer control
5  *
6  * Author:	Torsten Schenk <torsten.schenk@zoho.com>
7  * Created:	Jan 01, 2011
8  * Copyright:	(C) Torsten Schenk
9  *
10  * Thanks to:
11  * - Holger Ruckdeschel: he found out how to control individual channel
12  *   volumes and introduced mute switch
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  */
19 
20 #include <linux/interrupt.h>
21 #include <sound/control.h>
22 #include <sound/tlv.h>
23 
24 #include "control.h"
25 #include "comm.h"
26 #include "chip.h"
27 
28 static char *opt_coax_texts[2] = { "Optical", "Coax" };
29 static char *line_phono_texts[2] = { "Line", "Phono" };
30 
31 /*
32  * data that needs to be sent to device. sets up card internal stuff.
33  * values dumped from windows driver and filtered by trial'n'error.
34  */
35 static const struct {
36 	u8 type;
37 	u8 reg;
38 	u8 value;
39 }
40 init_data[] = {
41 	{ 0x22, 0x00, 0x00 }, { 0x20, 0x00, 0x08 }, { 0x22, 0x01, 0x01 },
42 	{ 0x20, 0x01, 0x08 }, { 0x22, 0x02, 0x00 }, { 0x20, 0x02, 0x08 },
43 	{ 0x22, 0x03, 0x00 }, { 0x20, 0x03, 0x08 }, { 0x22, 0x04, 0x00 },
44 	{ 0x20, 0x04, 0x08 }, { 0x22, 0x05, 0x01 }, { 0x20, 0x05, 0x08 },
45 	{ 0x22, 0x04, 0x01 }, { 0x12, 0x04, 0x00 }, { 0x12, 0x05, 0x00 },
46 	{ 0x12, 0x0d, 0x38 }, { 0x12, 0x21, 0x82 }, { 0x12, 0x22, 0x80 },
47 	{ 0x12, 0x23, 0x00 }, { 0x12, 0x06, 0x02 }, { 0x12, 0x03, 0x00 },
48 	{ 0x12, 0x02, 0x00 }, { 0x22, 0x03, 0x01 },
49 	{ 0 } /* TERMINATING ENTRY */
50 };
51 
52 static const int rates_altsetting[] = { 1, 1, 2, 2, 3, 3 };
53 /* values to write to soundcard register for all samplerates */
54 static const u16 rates_6fire_vl[] = {0x00, 0x01, 0x00, 0x01, 0x00, 0x01};
55 static const u16 rates_6fire_vh[] = {0x11, 0x11, 0x10, 0x10, 0x00, 0x00};
56 
57 static DECLARE_TLV_DB_MINMAX(tlv_output, -9000, 0);
58 static DECLARE_TLV_DB_MINMAX(tlv_input, -1500, 1500);
59 
60 enum {
61 	DIGITAL_THRU_ONLY_SAMPLERATE = 3
62 };
63 
64 static void usb6fire_control_output_vol_update(struct control_runtime *rt)
65 {
66 	struct comm_runtime *comm_rt = rt->chip->comm;
67 	int i;
68 
69 	if (comm_rt)
70 		for (i = 0; i < 6; i++)
71 			if (!(rt->ovol_updated & (1 << i))) {
72 				comm_rt->write8(comm_rt, 0x12, 0x0f + i,
73 					180 - rt->output_vol[i]);
74 				rt->ovol_updated |= 1 << i;
75 			}
76 }
77 
78 static void usb6fire_control_output_mute_update(struct control_runtime *rt)
79 {
80 	struct comm_runtime *comm_rt = rt->chip->comm;
81 
82 	if (comm_rt)
83 		comm_rt->write8(comm_rt, 0x12, 0x0e, ~rt->output_mute);
84 }
85 
86 static void usb6fire_control_input_vol_update(struct control_runtime *rt)
87 {
88 	struct comm_runtime *comm_rt = rt->chip->comm;
89 	int i;
90 
91 	if (comm_rt)
92 		for (i = 0; i < 2; i++)
93 			if (!(rt->ivol_updated & (1 << i))) {
94 				comm_rt->write8(comm_rt, 0x12, 0x1c + i,
95 					rt->input_vol[i] & 0x3f);
96 				rt->ivol_updated |= 1 << i;
97 			}
98 }
99 
100 static void usb6fire_control_line_phono_update(struct control_runtime *rt)
101 {
102 	struct comm_runtime *comm_rt = rt->chip->comm;
103 	if (comm_rt) {
104 		comm_rt->write8(comm_rt, 0x22, 0x02, rt->line_phono_switch);
105 		comm_rt->write8(comm_rt, 0x21, 0x02, rt->line_phono_switch);
106 	}
107 }
108 
109 static void usb6fire_control_opt_coax_update(struct control_runtime *rt)
110 {
111 	struct comm_runtime *comm_rt = rt->chip->comm;
112 	if (comm_rt) {
113 		comm_rt->write8(comm_rt, 0x22, 0x00, rt->opt_coax_switch);
114 		comm_rt->write8(comm_rt, 0x21, 0x00, rt->opt_coax_switch);
115 	}
116 }
117 
118 static int usb6fire_control_set_rate(struct control_runtime *rt, int rate)
119 {
120 	int ret;
121 	struct usb_device *device = rt->chip->dev;
122 	struct comm_runtime *comm_rt = rt->chip->comm;
123 
124 	if (rate < 0 || rate >= CONTROL_N_RATES)
125 		return -EINVAL;
126 
127 	ret = usb_set_interface(device, 1, rates_altsetting[rate]);
128 	if (ret < 0)
129 		return ret;
130 
131 	/* set soundcard clock */
132 	ret = comm_rt->write16(comm_rt, 0x02, 0x01, rates_6fire_vl[rate],
133 			rates_6fire_vh[rate]);
134 	if (ret < 0)
135 		return ret;
136 
137 	return 0;
138 }
139 
140 static int usb6fire_control_set_channels(
141 	struct control_runtime *rt, int n_analog_out,
142 	int n_analog_in, bool spdif_out, bool spdif_in)
143 {
144 	int ret;
145 	struct comm_runtime *comm_rt = rt->chip->comm;
146 
147 	/* enable analog inputs and outputs
148 	 * (one bit per stereo-channel) */
149 	ret = comm_rt->write16(comm_rt, 0x02, 0x02,
150 			(1 << (n_analog_out / 2)) - 1,
151 			(1 << (n_analog_in / 2)) - 1);
152 	if (ret < 0)
153 		return ret;
154 
155 	/* disable digital inputs and outputs */
156 	/* TODO: use spdif_x to enable/disable digital channels */
157 	ret = comm_rt->write16(comm_rt, 0x02, 0x03, 0x00, 0x00);
158 	if (ret < 0)
159 		return ret;
160 
161 	return 0;
162 }
163 
164 static int usb6fire_control_streaming_update(struct control_runtime *rt)
165 {
166 	struct comm_runtime *comm_rt = rt->chip->comm;
167 
168 	if (comm_rt) {
169 		if (!rt->usb_streaming && rt->digital_thru_switch)
170 			usb6fire_control_set_rate(rt,
171 				DIGITAL_THRU_ONLY_SAMPLERATE);
172 		return comm_rt->write16(comm_rt, 0x02, 0x00, 0x00,
173 			(rt->usb_streaming ? 0x01 : 0x00) |
174 			(rt->digital_thru_switch ? 0x08 : 0x00));
175 	}
176 	return -EINVAL;
177 }
178 
179 static int usb6fire_control_output_vol_info(struct snd_kcontrol *kcontrol,
180 		struct snd_ctl_elem_info *uinfo)
181 {
182 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
183 	uinfo->count = 2;
184 	uinfo->value.integer.min = 0;
185 	uinfo->value.integer.max = 180;
186 	return 0;
187 }
188 
189 static int usb6fire_control_output_vol_put(struct snd_kcontrol *kcontrol,
190 		struct snd_ctl_elem_value *ucontrol)
191 {
192 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
193 	unsigned int ch = kcontrol->private_value;
194 	int changed = 0;
195 
196 	if (ch > 4) {
197 		dev_err(&rt->chip->dev->dev,
198 			"Invalid channel in volume control.");
199 		return -EINVAL;
200 	}
201 
202 	if (rt->output_vol[ch] != ucontrol->value.integer.value[0]) {
203 		rt->output_vol[ch] = ucontrol->value.integer.value[0];
204 		rt->ovol_updated &= ~(1 << ch);
205 		changed = 1;
206 	}
207 	if (rt->output_vol[ch + 1] != ucontrol->value.integer.value[1]) {
208 		rt->output_vol[ch + 1] = ucontrol->value.integer.value[1];
209 		rt->ovol_updated &= ~(2 << ch);
210 		changed = 1;
211 	}
212 
213 	if (changed)
214 		usb6fire_control_output_vol_update(rt);
215 
216 	return changed;
217 }
218 
219 static int usb6fire_control_output_vol_get(struct snd_kcontrol *kcontrol,
220 		struct snd_ctl_elem_value *ucontrol)
221 {
222 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
223 	unsigned int ch = kcontrol->private_value;
224 
225 	if (ch > 4) {
226 		dev_err(&rt->chip->dev->dev,
227 			"Invalid channel in volume control.");
228 		return -EINVAL;
229 	}
230 
231 	ucontrol->value.integer.value[0] = rt->output_vol[ch];
232 	ucontrol->value.integer.value[1] = rt->output_vol[ch + 1];
233 	return 0;
234 }
235 
236 static int usb6fire_control_output_mute_put(struct snd_kcontrol *kcontrol,
237 	struct snd_ctl_elem_value *ucontrol)
238 {
239 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
240 	unsigned int ch = kcontrol->private_value;
241 	u8 old = rt->output_mute;
242 	u8 value = 0;
243 
244 	if (ch > 4) {
245 		dev_err(&rt->chip->dev->dev,
246 			"Invalid channel in volume control.");
247 		return -EINVAL;
248 	}
249 
250 	rt->output_mute &= ~(3 << ch);
251 	if (ucontrol->value.integer.value[0])
252 		value |= 1;
253 	if (ucontrol->value.integer.value[1])
254 		value |= 2;
255 	rt->output_mute |= value << ch;
256 
257 	if (rt->output_mute != old)
258 		usb6fire_control_output_mute_update(rt);
259 
260 	return rt->output_mute != old;
261 }
262 
263 static int usb6fire_control_output_mute_get(struct snd_kcontrol *kcontrol,
264 	struct snd_ctl_elem_value *ucontrol)
265 {
266 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
267 	unsigned int ch = kcontrol->private_value;
268 	u8 value = rt->output_mute >> ch;
269 
270 	if (ch > 4) {
271 		dev_err(&rt->chip->dev->dev,
272 			"Invalid channel in volume control.");
273 		return -EINVAL;
274 	}
275 
276 	ucontrol->value.integer.value[0] = 1 & value;
277 	value >>= 1;
278 	ucontrol->value.integer.value[1] = 1 & value;
279 
280 	return 0;
281 }
282 
283 static int usb6fire_control_input_vol_info(struct snd_kcontrol *kcontrol,
284 		struct snd_ctl_elem_info *uinfo)
285 {
286 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
287 	uinfo->count = 2;
288 	uinfo->value.integer.min = 0;
289 	uinfo->value.integer.max = 30;
290 	return 0;
291 }
292 
293 static int usb6fire_control_input_vol_put(struct snd_kcontrol *kcontrol,
294 		struct snd_ctl_elem_value *ucontrol)
295 {
296 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
297 	int changed = 0;
298 
299 	if (rt->input_vol[0] != ucontrol->value.integer.value[0]) {
300 		rt->input_vol[0] = ucontrol->value.integer.value[0] - 15;
301 		rt->ivol_updated &= ~(1 << 0);
302 		changed = 1;
303 	}
304 	if (rt->input_vol[1] != ucontrol->value.integer.value[1]) {
305 		rt->input_vol[1] = ucontrol->value.integer.value[1] - 15;
306 		rt->ivol_updated &= ~(1 << 1);
307 		changed = 1;
308 	}
309 
310 	if (changed)
311 		usb6fire_control_input_vol_update(rt);
312 
313 	return changed;
314 }
315 
316 static int usb6fire_control_input_vol_get(struct snd_kcontrol *kcontrol,
317 		struct snd_ctl_elem_value *ucontrol)
318 {
319 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
320 
321 	ucontrol->value.integer.value[0] = rt->input_vol[0] + 15;
322 	ucontrol->value.integer.value[1] = rt->input_vol[1] + 15;
323 
324 	return 0;
325 }
326 
327 static int usb6fire_control_line_phono_info(struct snd_kcontrol *kcontrol,
328 		struct snd_ctl_elem_info *uinfo)
329 {
330 	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
331 	uinfo->count = 1;
332 	uinfo->value.enumerated.items = 2;
333 	if (uinfo->value.enumerated.item > 1)
334 		uinfo->value.enumerated.item = 1;
335 	strcpy(uinfo->value.enumerated.name,
336 			line_phono_texts[uinfo->value.enumerated.item]);
337 	return 0;
338 }
339 
340 static int usb6fire_control_line_phono_put(struct snd_kcontrol *kcontrol,
341 		struct snd_ctl_elem_value *ucontrol)
342 {
343 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
344 	int changed = 0;
345 	if (rt->line_phono_switch != ucontrol->value.integer.value[0]) {
346 		rt->line_phono_switch = ucontrol->value.integer.value[0];
347 		usb6fire_control_line_phono_update(rt);
348 		changed = 1;
349 	}
350 	return changed;
351 }
352 
353 static int usb6fire_control_line_phono_get(struct snd_kcontrol *kcontrol,
354 		struct snd_ctl_elem_value *ucontrol)
355 {
356 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
357 	ucontrol->value.integer.value[0] = rt->line_phono_switch;
358 	return 0;
359 }
360 
361 static int usb6fire_control_opt_coax_info(struct snd_kcontrol *kcontrol,
362 		struct snd_ctl_elem_info *uinfo)
363 {
364 	uinfo->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
365 	uinfo->count = 1;
366 	uinfo->value.enumerated.items = 2;
367 	if (uinfo->value.enumerated.item > 1)
368 		uinfo->value.enumerated.item = 1;
369 	strcpy(uinfo->value.enumerated.name,
370 			opt_coax_texts[uinfo->value.enumerated.item]);
371 	return 0;
372 }
373 
374 static int usb6fire_control_opt_coax_put(struct snd_kcontrol *kcontrol,
375 		struct snd_ctl_elem_value *ucontrol)
376 {
377 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
378 	int changed = 0;
379 
380 	if (rt->opt_coax_switch != ucontrol->value.enumerated.item[0]) {
381 		rt->opt_coax_switch = ucontrol->value.enumerated.item[0];
382 		usb6fire_control_opt_coax_update(rt);
383 		changed = 1;
384 	}
385 	return changed;
386 }
387 
388 static int usb6fire_control_opt_coax_get(struct snd_kcontrol *kcontrol,
389 		struct snd_ctl_elem_value *ucontrol)
390 {
391 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
392 	ucontrol->value.enumerated.item[0] = rt->opt_coax_switch;
393 	return 0;
394 }
395 
396 static int usb6fire_control_digital_thru_put(struct snd_kcontrol *kcontrol,
397 		struct snd_ctl_elem_value *ucontrol)
398 {
399 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
400 	int changed = 0;
401 
402 	if (rt->digital_thru_switch != ucontrol->value.integer.value[0]) {
403 		rt->digital_thru_switch = ucontrol->value.integer.value[0];
404 		usb6fire_control_streaming_update(rt);
405 		changed = 1;
406 	}
407 	return changed;
408 }
409 
410 static int usb6fire_control_digital_thru_get(struct snd_kcontrol *kcontrol,
411 		struct snd_ctl_elem_value *ucontrol)
412 {
413 	struct control_runtime *rt = snd_kcontrol_chip(kcontrol);
414 	ucontrol->value.integer.value[0] = rt->digital_thru_switch;
415 	return 0;
416 }
417 
418 static struct snd_kcontrol_new vol_elements[] = {
419 	{
420 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
421 		.name = "Analog Playback Volume",
422 		.index = 0,
423 		.private_value = 0,
424 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
425 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
426 		.info = usb6fire_control_output_vol_info,
427 		.get = usb6fire_control_output_vol_get,
428 		.put = usb6fire_control_output_vol_put,
429 		.tlv = { .p = tlv_output }
430 	},
431 	{
432 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
433 		.name = "Analog Playback Volume",
434 		.index = 1,
435 		.private_value = 2,
436 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
437 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
438 		.info = usb6fire_control_output_vol_info,
439 		.get = usb6fire_control_output_vol_get,
440 		.put = usb6fire_control_output_vol_put,
441 		.tlv = { .p = tlv_output }
442 	},
443 	{
444 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
445 		.name = "Analog Playback Volume",
446 		.index = 2,
447 		.private_value = 4,
448 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
449 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
450 		.info = usb6fire_control_output_vol_info,
451 		.get = usb6fire_control_output_vol_get,
452 		.put = usb6fire_control_output_vol_put,
453 		.tlv = { .p = tlv_output }
454 	},
455 	{}
456 };
457 
458 static struct snd_kcontrol_new mute_elements[] = {
459 	{
460 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
461 		.name = "Analog Playback Switch",
462 		.index = 0,
463 		.private_value = 0,
464 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
465 		.info = snd_ctl_boolean_stereo_info,
466 		.get = usb6fire_control_output_mute_get,
467 		.put = usb6fire_control_output_mute_put,
468 	},
469 	{
470 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
471 		.name = "Analog Playback Switch",
472 		.index = 1,
473 		.private_value = 2,
474 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
475 		.info = snd_ctl_boolean_stereo_info,
476 		.get = usb6fire_control_output_mute_get,
477 		.put = usb6fire_control_output_mute_put,
478 	},
479 	{
480 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
481 		.name = "Analog Playback Switch",
482 		.index = 2,
483 		.private_value = 4,
484 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
485 		.info = snd_ctl_boolean_stereo_info,
486 		.get = usb6fire_control_output_mute_get,
487 		.put = usb6fire_control_output_mute_put,
488 	},
489 	{}
490 };
491 
492 static struct snd_kcontrol_new elements[] = {
493 	{
494 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
495 		.name = "Line/Phono Capture Route",
496 		.index = 0,
497 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
498 		.info = usb6fire_control_line_phono_info,
499 		.get = usb6fire_control_line_phono_get,
500 		.put = usb6fire_control_line_phono_put
501 	},
502 	{
503 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
504 		.name = "Opt/Coax Capture Route",
505 		.index = 0,
506 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
507 		.info = usb6fire_control_opt_coax_info,
508 		.get = usb6fire_control_opt_coax_get,
509 		.put = usb6fire_control_opt_coax_put
510 	},
511 	{
512 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
513 		.name = "Digital Thru Playback Route",
514 		.index = 0,
515 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE,
516 		.info = snd_ctl_boolean_mono_info,
517 		.get = usb6fire_control_digital_thru_get,
518 		.put = usb6fire_control_digital_thru_put
519 	},
520 	{
521 		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
522 		.name = "Analog Capture Volume",
523 		.index = 0,
524 		.access = SNDRV_CTL_ELEM_ACCESS_READWRITE |
525 			SNDRV_CTL_ELEM_ACCESS_TLV_READ,
526 		.info = usb6fire_control_input_vol_info,
527 		.get = usb6fire_control_input_vol_get,
528 		.put = usb6fire_control_input_vol_put,
529 		.tlv = { .p = tlv_input }
530 	},
531 	{}
532 };
533 
534 static int usb6fire_control_add_virtual(
535 	struct control_runtime *rt,
536 	struct snd_card *card,
537 	char *name,
538 	struct snd_kcontrol_new *elems)
539 {
540 	int ret;
541 	int i;
542 	struct snd_kcontrol *vmaster =
543 		snd_ctl_make_virtual_master(name, tlv_output);
544 	struct snd_kcontrol *control;
545 
546 	if (!vmaster)
547 		return -ENOMEM;
548 	ret = snd_ctl_add(card, vmaster);
549 	if (ret < 0)
550 		return ret;
551 
552 	i = 0;
553 	while (elems[i].name) {
554 		control = snd_ctl_new1(&elems[i], rt);
555 		if (!control)
556 			return -ENOMEM;
557 		ret = snd_ctl_add(card, control);
558 		if (ret < 0)
559 			return ret;
560 		ret = snd_ctl_add_slave(vmaster, control);
561 		if (ret < 0)
562 			return ret;
563 		i++;
564 	}
565 	return 0;
566 }
567 
568 int usb6fire_control_init(struct sfire_chip *chip)
569 {
570 	int i;
571 	int ret;
572 	struct control_runtime *rt = kzalloc(sizeof(struct control_runtime),
573 			GFP_KERNEL);
574 	struct comm_runtime *comm_rt = chip->comm;
575 
576 	if (!rt)
577 		return -ENOMEM;
578 
579 	rt->chip = chip;
580 	rt->update_streaming = usb6fire_control_streaming_update;
581 	rt->set_rate = usb6fire_control_set_rate;
582 	rt->set_channels = usb6fire_control_set_channels;
583 
584 	i = 0;
585 	while (init_data[i].type) {
586 		comm_rt->write8(comm_rt, init_data[i].type, init_data[i].reg,
587 				init_data[i].value);
588 		i++;
589 	}
590 
591 	usb6fire_control_opt_coax_update(rt);
592 	usb6fire_control_line_phono_update(rt);
593 	usb6fire_control_output_vol_update(rt);
594 	usb6fire_control_output_mute_update(rt);
595 	usb6fire_control_input_vol_update(rt);
596 	usb6fire_control_streaming_update(rt);
597 
598 	ret = usb6fire_control_add_virtual(rt, chip->card,
599 		"Master Playback Volume", vol_elements);
600 	if (ret) {
601 		dev_err(&chip->dev->dev, "cannot add control.\n");
602 		kfree(rt);
603 		return ret;
604 	}
605 	ret = usb6fire_control_add_virtual(rt, chip->card,
606 		"Master Playback Switch", mute_elements);
607 	if (ret) {
608 		dev_err(&chip->dev->dev, "cannot add control.\n");
609 		kfree(rt);
610 		return ret;
611 	}
612 
613 	i = 0;
614 	while (elements[i].name) {
615 		ret = snd_ctl_add(chip->card, snd_ctl_new1(&elements[i], rt));
616 		if (ret < 0) {
617 			kfree(rt);
618 			dev_err(&chip->dev->dev, "cannot add control.\n");
619 			return ret;
620 		}
621 		i++;
622 	}
623 
624 	chip->control = rt;
625 	return 0;
626 }
627 
628 void usb6fire_control_abort(struct sfire_chip *chip)
629 {}
630 
631 void usb6fire_control_destroy(struct sfire_chip *chip)
632 {
633 	kfree(chip->control);
634 	chip->control = NULL;
635 }
636