1	// SPDX-License-Identifier: GPL-2.0+
2	/*
3	* u_audio.c -- interface to USB gadget "ALSA sound card" utilities
4	*
5	* Copyright (C) 2016
6	* Author: Ruslan Bilovol <ruslan.bilovol@gmail.com>
7	*
8	* Sound card implementation was cut-and-pasted with changes
9	* from f_uac2.c and has:
10	* Copyright (C) 2011
11	* Yadwinder Singh (yadi.brar01@gmail.com)
12	* Jaswinder Singh (jaswinder.singh@linaro.org)
13	*/
14
15	#include <linux/kernel.h>
16	#include <linux/module.h>
17	#include <sound/core.h>
18	#include <sound/pcm.h>
19	#include <sound/pcm_params.h>
20	#include <sound/control.h>
21	#include <sound/tlv.h>
22	#include <linux/usb/audio.h>
23
24	#include "u_audio.h"
25
26	#define BUFF_SIZE_MAX (PAGE_SIZE * 16)
27	#define PRD_SIZE_MAX PAGE_SIZE
28	#define MIN_PERIODS 4
29
30	enum {
31	UAC_FBACK_CTRL,
32	UAC_P_PITCH_CTRL,
33	UAC_MUTE_CTRL,
34	UAC_VOLUME_CTRL,
35	UAC_RATE_CTRL,
36	};
37
38	/* Runtime data params for one stream */
39	struct uac_rtd_params {
40	struct snd_uac_chip *uac; /* parent chip */
41	bool ep_enabled; /* if the ep is enabled */
42
43	struct snd_pcm_substream *ss;
44
45	/* Ring buffer */
46	ssize_t hw_ptr;
47
48	void *rbuf;
49
50	unsigned int pitch; /* Stream pitch ratio to 1000000 */
51	unsigned int max_psize; /* MaxPacketSize of endpoint */
52
53	struct usb_request **reqs;
54
55	struct usb_request *req_fback; /* Feedback endpoint request */
56	bool fb_ep_enabled; /* if the ep is enabled */
57
58	/* Volume/Mute controls and their state */
59	int fu_id; /* Feature Unit ID */
60	struct snd_ctl_elem_id snd_kctl_volume_id;
61	struct snd_ctl_elem_id snd_kctl_mute_id;
62	s16 volume_min, volume_max, volume_res;
63	s16 volume;
64	int mute;
65
66	struct snd_ctl_elem_id snd_kctl_rate_id; /* read-only current rate */
67	int srate; /* selected samplerate */
68	int active; /* playback/capture running */
69
70	spinlock_t lock; /* lock for control transfers */
71
72	};
73
74	struct snd_uac_chip {
75	struct g_audio *audio_dev;
76
77	struct uac_rtd_params p_prm;
78	struct uac_rtd_params c_prm;
79
80	struct snd_card *card;
81	struct snd_pcm *pcm;
82
83	/* pre-calculated values for playback iso completion */
84	unsigned long long p_residue_mil;
85	unsigned int p_interval;
86	unsigned int p_framesize;
87	};
88
89	static const struct snd_pcm_hardware uac_pcm_hardware = {
90	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER
91	| SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
92	| SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
93	.rates = SNDRV_PCM_RATE_CONTINUOUS,
94	.periods_max = BUFF_SIZE_MAX / PRD_SIZE_MAX,
95	.buffer_bytes_max = BUFF_SIZE_MAX,
96	.period_bytes_max = PRD_SIZE_MAX,
97	.periods_min = MIN_PERIODS,
98	};
99
100	static void u_audio_set_fback_frequency(enum usb_device_speed speed,
101	struct usb_ep *out_ep,
102	unsigned long long freq,
103	unsigned int pitch,
104	void *buf)
105	{
106	u32 ff = 0;
107	const struct usb_endpoint_descriptor *ep_desc;
108
109	/*
110	* Because the pitch base is 1000000, the final divider here
111	* will be 1000 * 1000000 = 1953125 << 9
112	*
113	* Instead of dealing with big numbers lets fold this 9 left shift
114	*/
115
116	if (speed == USB_SPEED_FULL) {
117	/*
118	* Full-speed feedback endpoints report frequency
119	* in samples/frame
120	* Format is encoded in Q10.10 left-justified in the 24 bits,
121	* so that it has a Q10.14 format.
122	*
123	* ff = (freq << 14) / 1000
124	*/
125	freq <<= 5;
126	} else {
127	/*
128	* High-speed feedback endpoints report frequency
129	* in samples/microframe.
130	* Format is encoded in Q12.13 fitted into four bytes so that
131	* the binary point is located between the second and the third
132	* byte fromat (that is Q16.16)
133	*
134	* ff = (freq << 16) / 8000
135	*
136	* Win10 and OSX UAC2 drivers require number of samples per packet
137	* in order to honor the feedback value.
138	* Linux snd-usb-audio detects the applied bit-shift automatically.
139	*/
140	ep_desc = out_ep->desc;
141	freq <<= 4 + (ep_desc->bInterval - 1);
142	}
143
144	ff = DIV_ROUND_CLOSEST_ULL((freq * pitch), 1953125);
145
146	*(__le32 *)buf = cpu_to_le32(ff);
147	}
148
149	static void u_audio_iso_complete(struct usb_ep *ep, struct usb_request *req)
150	{
151	unsigned int pending;
152	unsigned int hw_ptr;
153	int status = req->status;
154	struct snd_pcm_substream *substream;
155	struct snd_pcm_runtime *runtime;
156	struct uac_rtd_params *prm = req->context;
157	struct snd_uac_chip *uac = prm->uac;
158	unsigned int frames, p_pktsize;
159	unsigned long long pitched_rate_mil, p_pktsize_residue_mil,
160	residue_frames_mil, div_result;
161
162	/* i/f shutting down */
163	if (!prm->ep_enabled) {
164	usb_ep_free_request(ep, req);
165	return;
166	}
167
168	if (req->status == -ESHUTDOWN)
169	return;
170
171	/*
172	* We can't really do much about bad xfers.
173	* Afterall, the ISOCH xfers could fail legitimately.
174	*/
175	if (status)
176	pr_debug("%s: iso_complete status(%d) %d/%d\n",
177	__func__, status, req->actual, req->length);
178
179	substream = prm->ss;
180
181	/* Do nothing if ALSA isn't active */
182	if (!substream)
183	goto exit;
184
185	snd_pcm_stream_lock(substream);
186
187	runtime = substream->runtime;
188	if (!runtime || !snd_pcm_running(substream)) {
189	snd_pcm_stream_unlock(substream);
190	goto exit;
191	}
192
193	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
194	/*
195	* For each IN packet, take the quotient of the current data
196	* rate and the endpoint's interval as the base packet size.
197	* If there is a residue from this division, add it to the
198	* residue accumulator.
199	*/
200	unsigned long long p_interval_mil = uac->p_interval * 1000000ULL;
201
202	pitched_rate_mil = (unsigned long long) prm->srate * prm->pitch;
203	div_result = pitched_rate_mil;
204	do_div(div_result, uac->p_interval);
205	do_div(div_result, 1000000);
206	frames = (unsigned int) div_result;
207
208	pr_debug("p_srate %d, pitch %d, interval_mil %llu, frames %d\n",
209	prm->srate, prm->pitch, p_interval_mil, frames);
210
211	p_pktsize = min_t(unsigned int,
212	uac->p_framesize * frames,
213	ep->maxpacket);
214
215	if (p_pktsize < ep->maxpacket) {
216	residue_frames_mil = pitched_rate_mil - frames * p_interval_mil;
217	p_pktsize_residue_mil = uac->p_framesize * residue_frames_mil;
218	} else
219	p_pktsize_residue_mil = 0;
220
221	req->length = p_pktsize;
222	uac->p_residue_mil += p_pktsize_residue_mil;
223
224	/*
225	* Whenever there are more bytes in the accumulator p_residue_mil than we
226	* need to add one more sample frame, increase this packet's
227	* size and decrease the accumulator.
228	*/
229	div_result = uac->p_residue_mil;
230	do_div(div_result, uac->p_interval);
231	do_div(div_result, 1000000);
232	if ((unsigned int) div_result >= uac->p_framesize) {
233	req->length += uac->p_framesize;
234	uac->p_residue_mil -= uac->p_framesize * p_interval_mil;
235	pr_debug("increased req length to %d\n", req->length);
236	}
237	pr_debug("remains uac->p_residue_mil %llu\n", uac->p_residue_mil);
238
239	req->actual = req->length;
240	}
241
242	hw_ptr = prm->hw_ptr;
243
244	/* Pack USB load in ALSA ring buffer */
245	pending = runtime->dma_bytes - hw_ptr;
246
247	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
248	if (unlikely(pending < req->actual)) {
249	memcpy(req->buf, runtime->dma_area + hw_ptr, pending);
250	memcpy(req->buf + pending, runtime->dma_area,
251	req->actual - pending);
252	} else {
253	memcpy(req->buf, runtime->dma_area + hw_ptr,
254	req->actual);
255	}
256	} else {
257	if (unlikely(pending < req->actual)) {
258	memcpy(runtime->dma_area + hw_ptr, req->buf, pending);
259	memcpy(runtime->dma_area, req->buf + pending,
260	req->actual - pending);
261	} else {
262	memcpy(runtime->dma_area + hw_ptr, req->buf,
263	req->actual);
264	}
265	}
266
267	/* update hw_ptr after data is copied to memory */
268	prm->hw_ptr = (hw_ptr + req->actual) % runtime->dma_bytes;
269	hw_ptr = prm->hw_ptr;
270	snd_pcm_stream_unlock(substream);
271
272	if ((hw_ptr % snd_pcm_lib_period_bytes(substream)) < req->actual)
273	snd_pcm_period_elapsed(substream);
274
275	exit:
276	if (usb_ep_queue(ep, req, GFP_ATOMIC))
277	dev_err(uac->card->dev, "%d Error!\n", __LINE__);
278	}
279
280	static void u_audio_iso_fback_complete(struct usb_ep *ep,
281	struct usb_request *req)
282	{
283	struct uac_rtd_params *prm = req->context;
284	struct snd_uac_chip *uac = prm->uac;
285	struct g_audio *audio_dev = uac->audio_dev;
286	int status = req->status;
287
288	/* i/f shutting down */
289	if (!prm->fb_ep_enabled) {
290	kfree(objp: req->buf);
291	usb_ep_free_request(ep, req);
292	return;
293	}
294
295	if (req->status == -ESHUTDOWN)
296	return;
297
298	/*
299	* We can't really do much about bad xfers.
300	* Afterall, the ISOCH xfers could fail legitimately.
301	*/
302	if (status)
303	pr_debug("%s: iso_complete status(%d) %d/%d\n",
304	__func__, status, req->actual, req->length);
305
306	u_audio_set_fback_frequency(speed: audio_dev->gadget->speed, out_ep: audio_dev->out_ep,
307	freq: prm->srate, pitch: prm->pitch,
308	buf: req->buf);
309
310	if (usb_ep_queue(ep, req, GFP_ATOMIC))
311	dev_err(uac->card->dev, "%d Error!\n", __LINE__);
312	}
313
314	static int uac_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
315	{
316	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
317	struct uac_rtd_params *prm;
318	struct g_audio *audio_dev;
319	struct uac_params *params;
320	int err = 0;
321
322	audio_dev = uac->audio_dev;
323	params = &audio_dev->params;
324
325	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
326	prm = &uac->p_prm;
327	else
328	prm = &uac->c_prm;
329
330	/* Reset */
331	prm->hw_ptr = 0;
332
333	switch (cmd) {
334	case SNDRV_PCM_TRIGGER_START:
335	case SNDRV_PCM_TRIGGER_RESUME:
336	prm->ss = substream;
337	break;
338	case SNDRV_PCM_TRIGGER_STOP:
339	case SNDRV_PCM_TRIGGER_SUSPEND:
340	prm->ss = NULL;
341	break;
342	default:
343	err = -EINVAL;
344	}
345
346	/* Clear buffer after Play stops */
347	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && !prm->ss)
348	memset(prm->rbuf, 0, prm->max_psize * params->req_number);
349
350	return err;
351	}
352
353	static snd_pcm_uframes_t uac_pcm_pointer(struct snd_pcm_substream *substream)
354	{
355	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
356	struct uac_rtd_params *prm;
357
358	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
359	prm = &uac->p_prm;
360	else
361	prm = &uac->c_prm;
362
363	return bytes_to_frames(runtime: substream->runtime, size: prm->hw_ptr);
364	}
365
366	static u64 uac_ssize_to_fmt(int ssize)
367	{
368	u64 ret;
369
370	switch (ssize) {
371	case 3:
372	ret = SNDRV_PCM_FMTBIT_S24_3LE;
373	break;
374	case 4:
375	ret = SNDRV_PCM_FMTBIT_S32_LE;
376	break;
377	default:
378	ret = SNDRV_PCM_FMTBIT_S16_LE;
379	break;
380	}
381
382	return ret;
383	}
384
385	static int uac_pcm_open(struct snd_pcm_substream *substream)
386	{
387	struct snd_uac_chip *uac = snd_pcm_substream_chip(substream);
388	struct snd_pcm_runtime *runtime = substream->runtime;
389	struct g_audio *audio_dev;
390	struct uac_params *params;
391	struct uac_rtd_params *prm;
392	int p_ssize, c_ssize;
393	int p_chmask, c_chmask;
394
395	audio_dev = uac->audio_dev;
396	params = &audio_dev->params;
397	p_ssize = params->p_ssize;
398	c_ssize = params->c_ssize;
399	p_chmask = params->p_chmask;
400	c_chmask = params->c_chmask;
401	uac->p_residue_mil = 0;
402
403	runtime->hw = uac_pcm_hardware;
404
405	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
406	runtime->hw.formats = uac_ssize_to_fmt(ssize: p_ssize);
407	runtime->hw.channels_min = num_channels(chanmask: p_chmask);
408	prm = &uac->p_prm;
409	} else {
410	runtime->hw.formats = uac_ssize_to_fmt(ssize: c_ssize);
411	runtime->hw.channels_min = num_channels(chanmask: c_chmask);
412	prm = &uac->c_prm;
413	}
414
415	runtime->hw.period_bytes_min = 2 * prm->max_psize
416	/ runtime->hw.periods_min;
417	runtime->hw.rate_min = prm->srate;
418	runtime->hw.rate_max = runtime->hw.rate_min;
419	runtime->hw.channels_max = runtime->hw.channels_min;
420
421	snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
422
423	return 0;
424	}
425
426	/* ALSA cries without these function pointers */
427	static int uac_pcm_null(struct snd_pcm_substream *substream)
428	{
429	return 0;
430	}
431
432	static const struct snd_pcm_ops uac_pcm_ops = {
433	.open = uac_pcm_open,
434	.close = uac_pcm_null,
435	.trigger = uac_pcm_trigger,
436	.pointer = uac_pcm_pointer,
437	.prepare = uac_pcm_null,
438	};
439
440	static inline void free_ep(struct uac_rtd_params *prm, struct usb_ep *ep)
441	{
442	struct snd_uac_chip *uac = prm->uac;
443	struct g_audio *audio_dev;
444	struct uac_params *params;
445	int i;
446
447	if (!prm->ep_enabled)
448	return;
449
450	audio_dev = uac->audio_dev;
451	params = &audio_dev->params;
452
453	for (i = 0; i < params->req_number; i++) {
454	if (prm->reqs[i]) {
455	if (usb_ep_dequeue(ep, req: prm->reqs[i]))
456	usb_ep_free_request(ep, req: prm->reqs[i]);
457	/*
458	* If usb_ep_dequeue() cannot successfully dequeue the
459	* request, the request will be freed by the completion
460	* callback.
461	*/
462
463	prm->reqs[i] = NULL;
464	}
465	}
466
467	prm->ep_enabled = false;
468
469	if (usb_ep_disable(ep))
470	dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
471	}
472
473	static inline void free_ep_fback(struct uac_rtd_params *prm, struct usb_ep *ep)
474	{
475	struct snd_uac_chip *uac = prm->uac;
476
477	if (!prm->fb_ep_enabled)
478	return;
479
480	if (prm->req_fback) {
481	if (usb_ep_dequeue(ep, req: prm->req_fback)) {
482	kfree(objp: prm->req_fback->buf);
483	usb_ep_free_request(ep, req: prm->req_fback);
484	}
485	prm->req_fback = NULL;
486	}
487
488	prm->fb_ep_enabled = false;
489
490	if (usb_ep_disable(ep))
491	dev_err(uac->card->dev, "%s:%d Error!\n", __func__, __LINE__);
492	}
493
494	static void set_active(struct uac_rtd_params *prm, bool active)
495	{
496	// notifying through the Rate ctrl
497	unsigned long flags;
498
499	spin_lock_irqsave(&prm->lock, flags);
500	if (prm->active != active) {
501	prm->active = active;
502	snd_ctl_notify(card: prm->uac->card, SNDRV_CTL_EVENT_MASK_VALUE,
503	id: &prm->snd_kctl_rate_id);
504	}
505	spin_unlock_irqrestore(lock: &prm->lock, flags);
506	}
507
508	int u_audio_set_capture_srate(struct g_audio *audio_dev, int srate)
509	{
510	struct uac_params *params = &audio_dev->params;
511	struct snd_uac_chip *uac = audio_dev->uac;
512	struct uac_rtd_params *prm;
513	int i;
514	unsigned long flags;
515
516	dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
517	prm = &uac->c_prm;
518	for (i = 0; i < UAC_MAX_RATES; i++) {
519	if (params->c_srates[i] == srate) {
520	spin_lock_irqsave(&prm->lock, flags);
521	prm->srate = srate;
522	spin_unlock_irqrestore(lock: &prm->lock, flags);
523	return 0;
524	}
525	if (params->c_srates[i] == 0)
526	break;
527	}
528
529	return -EINVAL;
530	}
531	EXPORT_SYMBOL_GPL(u_audio_set_capture_srate);
532
533	int u_audio_get_capture_srate(struct g_audio *audio_dev, u32 *val)
534	{
535	struct snd_uac_chip *uac = audio_dev->uac;
536	struct uac_rtd_params *prm;
537	unsigned long flags;
538
539	prm = &uac->c_prm;
540	spin_lock_irqsave(&prm->lock, flags);
541	*val = prm->srate;
542	spin_unlock_irqrestore(lock: &prm->lock, flags);
543	return 0;
544	}
545	EXPORT_SYMBOL_GPL(u_audio_get_capture_srate);
546
547	int u_audio_set_playback_srate(struct g_audio *audio_dev, int srate)
548	{
549	struct uac_params *params = &audio_dev->params;
550	struct snd_uac_chip *uac = audio_dev->uac;
551	struct uac_rtd_params *prm;
552	int i;
553	unsigned long flags;
554
555	dev_dbg(&audio_dev->gadget->dev, "%s: srate %d\n", __func__, srate);
556	prm = &uac->p_prm;
557	for (i = 0; i < UAC_MAX_RATES; i++) {
558	if (params->p_srates[i] == srate) {
559	spin_lock_irqsave(&prm->lock, flags);
560	prm->srate = srate;
561	spin_unlock_irqrestore(lock: &prm->lock, flags);
562	return 0;
563	}
564	if (params->p_srates[i] == 0)
565	break;
566	}
567
568	return -EINVAL;
569	}
570	EXPORT_SYMBOL_GPL(u_audio_set_playback_srate);
571
572	int u_audio_get_playback_srate(struct g_audio *audio_dev, u32 *val)
573	{
574	struct snd_uac_chip *uac = audio_dev->uac;
575	struct uac_rtd_params *prm;
576	unsigned long flags;
577
578	prm = &uac->p_prm;
579	spin_lock_irqsave(&prm->lock, flags);
580	*val = prm->srate;
581	spin_unlock_irqrestore(lock: &prm->lock, flags);
582	return 0;
583	}
584	EXPORT_SYMBOL_GPL(u_audio_get_playback_srate);
585
586	int u_audio_start_capture(struct g_audio *audio_dev)
587	{
588	struct snd_uac_chip *uac = audio_dev->uac;
589	struct usb_gadget *gadget = audio_dev->gadget;
590	struct device *dev = &gadget->dev;
591	struct usb_request *req, *req_fback;
592	struct usb_ep *ep, *ep_fback;
593	struct uac_rtd_params *prm;
594	struct uac_params *params = &audio_dev->params;
595	int req_len, i, ret;
596
597	prm = &uac->c_prm;
598	dev_dbg(dev, "start capture with rate %d\n", prm->srate);
599	ep = audio_dev->out_ep;
600	ret = config_ep_by_speed(g: gadget, f: &audio_dev->func, ep: ep);
601	if (ret < 0) {
602	dev_err(dev, "config_ep_by_speed for out_ep failed (%d)\n", ret);
603	return ret;
604	}
605
606	req_len = ep->maxpacket;
607
608	prm->ep_enabled = true;
609	ret = usb_ep_enable(ep);
610	if (ret < 0) {
611	dev_err(dev, "usb_ep_enable failed for out_ep (%d)\n", ret);
612	return ret;
613	}
614
615	for (i = 0; i < params->req_number; i++) {
616	if (!prm->reqs[i]) {
617	req = usb_ep_alloc_request(ep, GFP_ATOMIC);
618	if (req == NULL)
619	return -ENOMEM;
620
621	prm->reqs[i] = req;
622
623	req->zero = 0;
624	req->context = prm;
625	req->length = req_len;
626	req->complete = u_audio_iso_complete;
627	req->buf = prm->rbuf + i * ep->maxpacket;
628	}
629
630	if (usb_ep_queue(ep, req: prm->reqs[i], GFP_ATOMIC))
631	dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
632	}
633
634	set_active(prm: &uac->c_prm, active: true);
635
636	ep_fback = audio_dev->in_ep_fback;
637	if (!ep_fback)
638	return 0;
639
640	/* Setup feedback endpoint */
641	ret = config_ep_by_speed(g: gadget, f: &audio_dev->func, ep: ep_fback);
642	if (ret < 0) {
643	dev_err(dev, "config_ep_by_speed in_ep_fback failed (%d)\n", ret);
644	return ret; // TODO: Clean up out_ep
645	}
646
647	prm->fb_ep_enabled = true;
648	ret = usb_ep_enable(ep: ep_fback);
649	if (ret < 0) {
650	dev_err(dev, "usb_ep_enable failed for in_ep_fback (%d)\n", ret);
651	return ret; // TODO: Clean up out_ep
652	}
653	req_len = ep_fback->maxpacket;
654
655	req_fback = usb_ep_alloc_request(ep: ep_fback, GFP_ATOMIC);
656	if (req_fback == NULL)
657	return -ENOMEM;
658
659	prm->req_fback = req_fback;
660	req_fback->zero = 0;
661	req_fback->context = prm;
662	req_fback->length = req_len;
663	req_fback->complete = u_audio_iso_fback_complete;
664
665	req_fback->buf = kzalloc(req_len, GFP_ATOMIC);
666	if (!req_fback->buf)
667	return -ENOMEM;
668
669	/*
670	* Configure the feedback endpoint's reported frequency.
671	* Always start with original frequency since its deviation can't
672	* be meauserd at start of playback
673	*/
674	prm->pitch = 1000000;
675	u_audio_set_fback_frequency(speed: audio_dev->gadget->speed, out_ep: ep,
676	freq: prm->srate, pitch: prm->pitch,
677	buf: req_fback->buf);
678
679	if (usb_ep_queue(ep: ep_fback, req: req_fback, GFP_ATOMIC))
680	dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
681
682	return 0;
683	}
684	EXPORT_SYMBOL_GPL(u_audio_start_capture);
685
686	void u_audio_stop_capture(struct g_audio *audio_dev)
687	{
688	struct snd_uac_chip *uac = audio_dev->uac;
689
690	set_active(prm: &uac->c_prm, active: false);
691	if (audio_dev->in_ep_fback)
692	free_ep_fback(prm: &uac->c_prm, ep: audio_dev->in_ep_fback);
693	free_ep(prm: &uac->c_prm, ep: audio_dev->out_ep);
694	}
695	EXPORT_SYMBOL_GPL(u_audio_stop_capture);
696
697	int u_audio_start_playback(struct g_audio *audio_dev)
698	{
699	struct snd_uac_chip *uac = audio_dev->uac;
700	struct usb_gadget *gadget = audio_dev->gadget;
701	struct device *dev = &gadget->dev;
702	struct usb_request *req;
703	struct usb_ep *ep;
704	struct uac_rtd_params *prm;
705	struct uac_params *params = &audio_dev->params;
706	unsigned int factor;
707	const struct usb_endpoint_descriptor *ep_desc;
708	int req_len, i, ret;
709	unsigned int p_pktsize;
710
711	prm = &uac->p_prm;
712	dev_dbg(dev, "start playback with rate %d\n", prm->srate);
713	ep = audio_dev->in_ep;
714	ret = config_ep_by_speed(g: gadget, f: &audio_dev->func, ep: ep);
715	if (ret < 0) {
716	dev_err(dev, "config_ep_by_speed for in_ep failed (%d)\n", ret);
717	return ret;
718	}
719
720	ep_desc = ep->desc;
721	/*
722	* Always start with original frequency
723	*/
724	prm->pitch = 1000000;
725
726	/* pre-calculate the playback endpoint's interval */
727	if (gadget->speed == USB_SPEED_FULL)
728	factor = 1000;
729	else
730	factor = 8000;
731
732	/* pre-compute some values for iso_complete() */
733	uac->p_framesize = params->p_ssize *
734	num_channels(chanmask: params->p_chmask);
735	uac->p_interval = factor / (1 << (ep_desc->bInterval - 1));
736	p_pktsize = min_t(unsigned int,
737	uac->p_framesize *
738	(prm->srate / uac->p_interval),
739	ep->maxpacket);
740
741	req_len = p_pktsize;
742	uac->p_residue_mil = 0;
743
744	prm->ep_enabled = true;
745	ret = usb_ep_enable(ep);
746	if (ret < 0) {
747	dev_err(dev, "usb_ep_enable failed for in_ep (%d)\n", ret);
748	return ret;
749	}
750
751	for (i = 0; i < params->req_number; i++) {
752	if (!prm->reqs[i]) {
753	req = usb_ep_alloc_request(ep, GFP_ATOMIC);
754	if (req == NULL)
755	return -ENOMEM;
756
757	prm->reqs[i] = req;
758
759	req->zero = 0;
760	req->context = prm;
761	req->length = req_len;
762	req->complete = u_audio_iso_complete;
763	req->buf = prm->rbuf + i * ep->maxpacket;
764	}
765
766	if (usb_ep_queue(ep, req: prm->reqs[i], GFP_ATOMIC))
767	dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
768	}
769
770	set_active(prm: &uac->p_prm, active: true);
771
772	return 0;
773	}
774	EXPORT_SYMBOL_GPL(u_audio_start_playback);
775
776	void u_audio_stop_playback(struct g_audio *audio_dev)
777	{
778	struct snd_uac_chip *uac = audio_dev->uac;
779
780	set_active(prm: &uac->p_prm, active: false);
781	free_ep(prm: &uac->p_prm, ep: audio_dev->in_ep);
782	}
783	EXPORT_SYMBOL_GPL(u_audio_stop_playback);
784
785	void u_audio_suspend(struct g_audio *audio_dev)
786	{
787	struct snd_uac_chip *uac = audio_dev->uac;
788
789	set_active(prm: &uac->p_prm, active: false);
790	set_active(prm: &uac->c_prm, active: false);
791	}
792	EXPORT_SYMBOL_GPL(u_audio_suspend);
793
794	int u_audio_get_volume(struct g_audio *audio_dev, int playback, s16 *val)
795	{
796	struct snd_uac_chip *uac = audio_dev->uac;
797	struct uac_rtd_params *prm;
798	unsigned long flags;
799
800	if (playback)
801	prm = &uac->p_prm;
802	else
803	prm = &uac->c_prm;
804
805	spin_lock_irqsave(&prm->lock, flags);
806	*val = prm->volume;
807	spin_unlock_irqrestore(lock: &prm->lock, flags);
808
809	return 0;
810	}
811	EXPORT_SYMBOL_GPL(u_audio_get_volume);
812
813	int u_audio_set_volume(struct g_audio *audio_dev, int playback, s16 val)
814	{
815	struct snd_uac_chip *uac = audio_dev->uac;
816	struct uac_rtd_params *prm;
817	unsigned long flags;
818	int change = 0;
819
820	if (playback)
821	prm = &uac->p_prm;
822	else
823	prm = &uac->c_prm;
824
825	spin_lock_irqsave(&prm->lock, flags);
826	val = clamp(val, prm->volume_min, prm->volume_max);
827	if (prm->volume != val) {
828	prm->volume = val;
829	change = 1;
830	}
831	spin_unlock_irqrestore(lock: &prm->lock, flags);
832
833	if (change)
834	snd_ctl_notify(card: uac->card, SNDRV_CTL_EVENT_MASK_VALUE,
835	id: &prm->snd_kctl_volume_id);
836
837	return 0;
838	}
839	EXPORT_SYMBOL_GPL(u_audio_set_volume);
840
841	int u_audio_get_mute(struct g_audio *audio_dev, int playback, int *val)
842	{
843	struct snd_uac_chip *uac = audio_dev->uac;
844	struct uac_rtd_params *prm;
845	unsigned long flags;
846
847	if (playback)
848	prm = &uac->p_prm;
849	else
850	prm = &uac->c_prm;
851
852	spin_lock_irqsave(&prm->lock, flags);
853	*val = prm->mute;
854	spin_unlock_irqrestore(lock: &prm->lock, flags);
855
856	return 0;
857	}
858	EXPORT_SYMBOL_GPL(u_audio_get_mute);
859
860	int u_audio_set_mute(struct g_audio *audio_dev, int playback, int val)
861	{
862	struct snd_uac_chip *uac = audio_dev->uac;
863	struct uac_rtd_params *prm;
864	unsigned long flags;
865	int change = 0;
866	int mute;
867
868	if (playback)
869	prm = &uac->p_prm;
870	else
871	prm = &uac->c_prm;
872
873	mute = val ? 1 : 0;
874
875	spin_lock_irqsave(&prm->lock, flags);
876	if (prm->mute != mute) {
877	prm->mute = mute;
878	change = 1;
879	}
880	spin_unlock_irqrestore(lock: &prm->lock, flags);
881
882	if (change)
883	snd_ctl_notify(card: uac->card, SNDRV_CTL_EVENT_MASK_VALUE,
884	id: &prm->snd_kctl_mute_id);
885
886	return 0;
887	}
888	EXPORT_SYMBOL_GPL(u_audio_set_mute);
889
890
891	static int u_audio_pitch_info(struct snd_kcontrol *kcontrol,
892	struct snd_ctl_elem_info *uinfo)
893	{
894	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
895	struct snd_uac_chip *uac = prm->uac;
896	struct g_audio *audio_dev = uac->audio_dev;
897	struct uac_params *params = &audio_dev->params;
898	unsigned int pitch_min, pitch_max;
899
900	pitch_min = (1000 - FBACK_SLOW_MAX) * 1000;
901	pitch_max = (1000 + params->fb_max) * 1000;
902
903	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
904	uinfo->count = 1;
905	uinfo->value.integer.min = pitch_min;
906	uinfo->value.integer.max = pitch_max;
907	uinfo->value.integer.step = 1;
908	return 0;
909	}
910
911	static int u_audio_pitch_get(struct snd_kcontrol *kcontrol,
912	struct snd_ctl_elem_value *ucontrol)
913	{
914	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
915
916	ucontrol->value.integer.value[0] = prm->pitch;
917
918	return 0;
919	}
920
921	static int u_audio_pitch_put(struct snd_kcontrol *kcontrol,
922	struct snd_ctl_elem_value *ucontrol)
923	{
924	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
925	struct snd_uac_chip *uac = prm->uac;
926	struct g_audio *audio_dev = uac->audio_dev;
927	struct uac_params *params = &audio_dev->params;
928	unsigned int val;
929	unsigned int pitch_min, pitch_max;
930	int change = 0;
931
932	pitch_min = (1000 - FBACK_SLOW_MAX) * 1000;
933	pitch_max = (1000 + params->fb_max) * 1000;
934
935	val = ucontrol->value.integer.value[0];
936
937	if (val < pitch_min)
938	val = pitch_min;
939	if (val > pitch_max)
940	val = pitch_max;
941
942	if (prm->pitch != val) {
943	prm->pitch = val;
944	change = 1;
945	}
946
947	return change;
948	}
949
950	static int u_audio_mute_info(struct snd_kcontrol *kcontrol,
951	struct snd_ctl_elem_info *uinfo)
952	{
953	uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
954	uinfo->count = 1;
955	uinfo->value.integer.min = 0;
956	uinfo->value.integer.max = 1;
957	uinfo->value.integer.step = 1;
958
959	return 0;
960	}
961
962	static int u_audio_mute_get(struct snd_kcontrol *kcontrol,
963	struct snd_ctl_elem_value *ucontrol)
964	{
965	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
966	unsigned long flags;
967
968	spin_lock_irqsave(&prm->lock, flags);
969	ucontrol->value.integer.value[0] = !prm->mute;
970	spin_unlock_irqrestore(lock: &prm->lock, flags);
971
972	return 0;
973	}
974
975	static int u_audio_mute_put(struct snd_kcontrol *kcontrol,
976	struct snd_ctl_elem_value *ucontrol)
977	{
978	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
979	struct snd_uac_chip *uac = prm->uac;
980	struct g_audio *audio_dev = uac->audio_dev;
981	unsigned int val;
982	unsigned long flags;
983	int change = 0;
984
985	val = !ucontrol->value.integer.value[0];
986
987	spin_lock_irqsave(&prm->lock, flags);
988	if (val != prm->mute) {
989	prm->mute = val;
990	change = 1;
991	}
992	spin_unlock_irqrestore(lock: &prm->lock, flags);
993
994	if (change && audio_dev->notify)
995	audio_dev->notify(audio_dev, prm->fu_id, UAC_FU_MUTE);
996
997	return change;
998	}
999
1000	/*
1001	* TLV callback for mixer volume controls
1002	*/
1003	static int u_audio_volume_tlv(struct snd_kcontrol *kcontrol, int op_flag,
1004	unsigned int size, unsigned int __user *_tlv)
1005	{
1006	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1007	DECLARE_TLV_DB_MINMAX(scale, 0, 0);
1008
1009	if (size < sizeof(scale))
1010	return -ENOMEM;
1011
1012	/* UAC volume resolution is 1/256 dB, TLV is 1/100 dB */
1013	scale[2] = (prm->volume_min * 100) / 256;
1014	scale[3] = (prm->volume_max * 100) / 256;
1015	if (copy_to_user(to: _tlv, from: scale, n: sizeof(scale)))
1016	return -EFAULT;
1017
1018	return 0;
1019	}
1020
1021	static int u_audio_volume_info(struct snd_kcontrol *kcontrol,
1022	struct snd_ctl_elem_info *uinfo)
1023	{
1024	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1025
1026	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1027	uinfo->count = 1;
1028	uinfo->value.integer.min = 0;
1029	uinfo->value.integer.max =
1030	(prm->volume_max - prm->volume_min + prm->volume_res - 1)
1031	/ prm->volume_res;
1032	uinfo->value.integer.step = 1;
1033
1034	return 0;
1035	}
1036
1037	static int u_audio_volume_get(struct snd_kcontrol *kcontrol,
1038	struct snd_ctl_elem_value *ucontrol)
1039	{
1040	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1041	unsigned long flags;
1042
1043	spin_lock_irqsave(&prm->lock, flags);
1044	ucontrol->value.integer.value[0] =
1045	(prm->volume - prm->volume_min) / prm->volume_res;
1046	spin_unlock_irqrestore(lock: &prm->lock, flags);
1047
1048	return 0;
1049	}
1050
1051	static int u_audio_volume_put(struct snd_kcontrol *kcontrol,
1052	struct snd_ctl_elem_value *ucontrol)
1053	{
1054	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1055	struct snd_uac_chip *uac = prm->uac;
1056	struct g_audio *audio_dev = uac->audio_dev;
1057	unsigned int val;
1058	s16 volume;
1059	unsigned long flags;
1060	int change = 0;
1061
1062	val = ucontrol->value.integer.value[0];
1063
1064	spin_lock_irqsave(&prm->lock, flags);
1065	volume = (val * prm->volume_res) + prm->volume_min;
1066	volume = clamp(volume, prm->volume_min, prm->volume_max);
1067	if (volume != prm->volume) {
1068	prm->volume = volume;
1069	change = 1;
1070	}
1071	spin_unlock_irqrestore(lock: &prm->lock, flags);
1072
1073	if (change && audio_dev->notify)
1074	audio_dev->notify(audio_dev, prm->fu_id, UAC_FU_VOLUME);
1075
1076	return change;
1077	}
1078
1079	static int get_max_srate(const int *srates)
1080	{
1081	int i, max_srate = 0;
1082
1083	for (i = 0; i < UAC_MAX_RATES; i++) {
1084	if (srates[i] == 0)
1085	break;
1086	if (srates[i] > max_srate)
1087	max_srate = srates[i];
1088	}
1089	return max_srate;
1090	}
1091
1092	static int get_min_srate(const int *srates)
1093	{
1094	int i, min_srate = INT_MAX;
1095
1096	for (i = 0; i < UAC_MAX_RATES; i++) {
1097	if (srates[i] == 0)
1098	break;
1099	if (srates[i] < min_srate)
1100	min_srate = srates[i];
1101	}
1102	return min_srate;
1103	}
1104
1105	static int u_audio_rate_info(struct snd_kcontrol *kcontrol,
1106	struct snd_ctl_elem_info *uinfo)
1107	{
1108	const int *srates;
1109	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1110	struct snd_uac_chip *uac = prm->uac;
1111	struct g_audio *audio_dev = uac->audio_dev;
1112	struct uac_params *params = &audio_dev->params;
1113
1114	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1115	uinfo->count = 1;
1116
1117	if (prm == &uac->c_prm)
1118	srates = params->c_srates;
1119	else
1120	srates = params->p_srates;
1121	uinfo->value.integer.min = get_min_srate(srates);
1122	uinfo->value.integer.max = get_max_srate(srates);
1123	return 0;
1124	}
1125
1126	static int u_audio_rate_get(struct snd_kcontrol *kcontrol,
1127	struct snd_ctl_elem_value *ucontrol)
1128	{
1129	struct uac_rtd_params *prm = snd_kcontrol_chip(kcontrol);
1130	unsigned long flags;
1131
1132	spin_lock_irqsave(&prm->lock, flags);
1133	if (prm->active)
1134	ucontrol->value.integer.value[0] = prm->srate;
1135	else
1136	/* not active: reporting zero rate */
1137	ucontrol->value.integer.value[0] = 0;
1138	spin_unlock_irqrestore(lock: &prm->lock, flags);
1139	return 0;
1140	}
1141
1142	static struct snd_kcontrol_new u_audio_controls[] = {
1143	[UAC_FBACK_CTRL] = {
1144	.iface = SNDRV_CTL_ELEM_IFACE_PCM,
1145	.name = "Capture Pitch 1000000",
1146	.info = u_audio_pitch_info,
1147	.get = u_audio_pitch_get,
1148	.put = u_audio_pitch_put,
1149	},
1150	[UAC_P_PITCH_CTRL] = {
1151	.iface = SNDRV_CTL_ELEM_IFACE_PCM,
1152	.name = "Playback Pitch 1000000",
1153	.info = u_audio_pitch_info,
1154	.get = u_audio_pitch_get,
1155	.put = u_audio_pitch_put,
1156	},
1157	[UAC_MUTE_CTRL] = {
1158	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1159	.name = "", /* will be filled later */
1160	.info = u_audio_mute_info,
1161	.get = u_audio_mute_get,
1162	.put = u_audio_mute_put,
1163	},
1164	[UAC_VOLUME_CTRL] = {
1165	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
1166	.name = "", /* will be filled later */
1167	.info = u_audio_volume_info,
1168	.get = u_audio_volume_get,
1169	.put = u_audio_volume_put,
1170	},
1171	[UAC_RATE_CTRL] = {
1172	.iface = SNDRV_CTL_ELEM_IFACE_PCM,
1173	.name = "", /* will be filled later */
1174	.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
1175	.info = u_audio_rate_info,
1176	.get = u_audio_rate_get,
1177	},
1178	};
1179
1180	int g_audio_setup(struct g_audio *g_audio, const char *pcm_name,
1181	const char *card_name)
1182	{
1183	struct snd_uac_chip *uac;
1184	struct snd_card *card;
1185	struct snd_pcm *pcm;
1186	struct snd_kcontrol *kctl;
1187	struct uac_params *params;
1188	int p_chmask, c_chmask;
1189	int i, err;
1190
1191	if (!g_audio)
1192	return -EINVAL;
1193
1194	uac = kzalloc(sizeof(*uac), GFP_KERNEL);
1195	if (!uac)
1196	return -ENOMEM;
1197	g_audio->uac = uac;
1198	uac->audio_dev = g_audio;
1199
1200	params = &g_audio->params;
1201	p_chmask = params->p_chmask;
1202	c_chmask = params->c_chmask;
1203
1204	if (c_chmask) {
1205	struct uac_rtd_params *prm = &uac->c_prm;
1206
1207	spin_lock_init(&prm->lock);
1208	uac->c_prm.uac = uac;
1209	prm->max_psize = g_audio->out_ep_maxpsize;
1210	prm->srate = params->c_srates[0];
1211
1212	prm->reqs = kcalloc(params->req_number,
1213	sizeof(struct usb_request *),
1214	GFP_KERNEL);
1215	if (!prm->reqs) {
1216	err = -ENOMEM;
1217	goto fail;
1218	}
1219
1220	prm->rbuf = kcalloc(params->req_number, prm->max_psize,
1221	GFP_KERNEL);
1222	if (!prm->rbuf) {
1223	prm->max_psize = 0;
1224	err = -ENOMEM;
1225	goto fail;
1226	}
1227	}
1228
1229	if (p_chmask) {
1230	struct uac_rtd_params *prm = &uac->p_prm;
1231
1232	spin_lock_init(&prm->lock);
1233	uac->p_prm.uac = uac;
1234	prm->max_psize = g_audio->in_ep_maxpsize;
1235	prm->srate = params->p_srates[0];
1236
1237	prm->reqs = kcalloc(params->req_number,
1238	sizeof(struct usb_request *),
1239	GFP_KERNEL);
1240	if (!prm->reqs) {
1241	err = -ENOMEM;
1242	goto fail;
1243	}
1244
1245	prm->rbuf = kcalloc(params->req_number, prm->max_psize,
1246	GFP_KERNEL);
1247	if (!prm->rbuf) {
1248	prm->max_psize = 0;
1249	err = -ENOMEM;
1250	goto fail;
1251	}
1252	}
1253
1254	/* Choose any slot, with no id */
1255	err = snd_card_new(parent: &g_audio->gadget->dev,
1256	idx: -1, NULL, THIS_MODULE, extra_size: 0, card_ret: &card);
1257	if (err < 0)
1258	goto fail;
1259
1260	uac->card = card;
1261
1262	/*
1263	* Create first PCM device
1264	* Create a substream only for non-zero channel streams
1265	*/
1266	err = snd_pcm_new(card: uac->card, id: pcm_name, device: 0,
1267	playback_count: p_chmask ? 1 : 0, capture_count: c_chmask ? 1 : 0, rpcm: &pcm);
1268	if (err < 0)
1269	goto snd_fail;
1270
1271	strscpy(pcm->name, pcm_name);
1272	pcm->private_data = uac;
1273	uac->pcm = pcm;
1274
1275	snd_pcm_set_ops(pcm, direction: SNDRV_PCM_STREAM_PLAYBACK, ops: &uac_pcm_ops);
1276	snd_pcm_set_ops(pcm, direction: SNDRV_PCM_STREAM_CAPTURE, ops: &uac_pcm_ops);
1277
1278	/*
1279	* Create mixer and controls
1280	* Create only if it's required on USB side
1281	*/
1282	if ((c_chmask && g_audio->in_ep_fback)
1283	|| (p_chmask && params->p_fu.id)
1284	|| (c_chmask && params->c_fu.id))
1285	strscpy(card->mixername, card_name);
1286
1287	if (c_chmask && g_audio->in_ep_fback) {
1288	kctl = snd_ctl_new1(kcontrolnew: &u_audio_controls[UAC_FBACK_CTRL],
1289	private_data: &uac->c_prm);
1290	if (!kctl) {
1291	err = -ENOMEM;
1292	goto snd_fail;
1293	}
1294
1295	kctl->id.device = pcm->device;
1296	kctl->id.subdevice = 0;
1297
1298	err = snd_ctl_add(card, kcontrol: kctl);
1299	if (err < 0)
1300	goto snd_fail;
1301	}
1302
1303	if (p_chmask) {
1304	kctl = snd_ctl_new1(kcontrolnew: &u_audio_controls[UAC_P_PITCH_CTRL],
1305	private_data: &uac->p_prm);
1306	if (!kctl) {
1307	err = -ENOMEM;
1308	goto snd_fail;
1309	}
1310
1311	kctl->id.device = pcm->device;
1312	kctl->id.subdevice = 0;
1313
1314	err = snd_ctl_add(card, kcontrol: kctl);
1315	if (err < 0)
1316	goto snd_fail;
1317	}
1318
1319	for (i = 0; i <= SNDRV_PCM_STREAM_LAST; i++) {
1320	struct uac_rtd_params *prm;
1321	struct uac_fu_params *fu;
1322	char ctrl_name[24];
1323	char *direction;
1324
1325	if (!pcm->streams[i].substream_count)
1326	continue;
1327
1328	if (i == SNDRV_PCM_STREAM_PLAYBACK) {
1329	prm = &uac->p_prm;
1330	fu = &params->p_fu;
1331	direction = "Playback";
1332	} else {
1333	prm = &uac->c_prm;
1334	fu = &params->c_fu;
1335	direction = "Capture";
1336	}
1337
1338	prm->fu_id = fu->id;
1339
1340	if (fu->mute_present) {
1341	snprintf(buf: ctrl_name, size: sizeof(ctrl_name),
1342	fmt: "PCM %s Switch", direction);
1343
1344	u_audio_controls[UAC_MUTE_CTRL].name = ctrl_name;
1345
1346	kctl = snd_ctl_new1(kcontrolnew: &u_audio_controls[UAC_MUTE_CTRL],
1347	private_data: prm);
1348	if (!kctl) {
1349	err = -ENOMEM;
1350	goto snd_fail;
1351	}
1352
1353	kctl->id.device = pcm->device;
1354	kctl->id.subdevice = 0;
1355
1356	err = snd_ctl_add(card, kcontrol: kctl);
1357	if (err < 0)
1358	goto snd_fail;
1359	prm->snd_kctl_mute_id = kctl->id;
1360	prm->mute = 0;
1361	}
1362
1363	if (fu->volume_present) {
1364	snprintf(buf: ctrl_name, size: sizeof(ctrl_name),
1365	fmt: "PCM %s Volume", direction);
1366
1367	u_audio_controls[UAC_VOLUME_CTRL].name = ctrl_name;
1368
1369	kctl = snd_ctl_new1(kcontrolnew: &u_audio_controls[UAC_VOLUME_CTRL],
1370	private_data: prm);
1371	if (!kctl) {
1372	err = -ENOMEM;
1373	goto snd_fail;
1374	}
1375
1376	kctl->id.device = pcm->device;
1377	kctl->id.subdevice = 0;
1378
1379
1380	kctl->tlv.c = u_audio_volume_tlv;
1381	kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ |
1382	SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
1383
1384	err = snd_ctl_add(card, kcontrol: kctl);
1385	if (err < 0)
1386	goto snd_fail;
1387	prm->snd_kctl_volume_id = kctl->id;
1388	prm->volume = fu->volume_max;
1389	prm->volume_max = fu->volume_max;
1390	prm->volume_min = fu->volume_min;
1391	prm->volume_res = fu->volume_res;
1392	}
1393
1394	/* Add rate control */
1395	snprintf(buf: ctrl_name, size: sizeof(ctrl_name),
1396	fmt: "%s Rate", direction);
1397	u_audio_controls[UAC_RATE_CTRL].name = ctrl_name;
1398
1399	kctl = snd_ctl_new1(kcontrolnew: &u_audio_controls[UAC_RATE_CTRL], private_data: prm);
1400	if (!kctl) {
1401	err = -ENOMEM;
1402	goto snd_fail;
1403	}
1404
1405	kctl->id.device = pcm->device;
1406	kctl->id.subdevice = 0;
1407
1408	err = snd_ctl_add(card, kcontrol: kctl);
1409	if (err < 0)
1410	goto snd_fail;
1411	prm->snd_kctl_rate_id = kctl->id;
1412	}
1413
1414	strscpy(card->driver, card_name);
1415	strscpy(card->shortname, card_name);
1416	snprintf(buf: card->longname, size: sizeof(card->longname), fmt: "%s %i",
1417	card_name, card->dev->id);
1418
1419	snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
1420	NULL, size: 0, BUFF_SIZE_MAX);
1421
1422	err = snd_card_register(card);
1423
1424	if (!err)
1425	return 0;
1426
1427	snd_fail:
1428	snd_card_free(card);
1429	fail:
1430	kfree(objp: uac->p_prm.reqs);
1431	kfree(objp: uac->c_prm.reqs);
1432	kfree(objp: uac->p_prm.rbuf);
1433	kfree(objp: uac->c_prm.rbuf);
1434	kfree(objp: uac);
1435
1436	return err;
1437	}
1438	EXPORT_SYMBOL_GPL(g_audio_setup);
1439
1440	void g_audio_cleanup(struct g_audio *g_audio)
1441	{
1442	struct snd_uac_chip *uac;
1443	struct snd_card *card;
1444
1445	if (!g_audio || !g_audio->uac)
1446	return;
1447
1448	uac = g_audio->uac;
1449	g_audio->uac = NULL;
1450
1451	card = uac->card;
1452	if (card)
1453	snd_card_free_when_closed(card);
1454
1455	kfree(objp: uac->p_prm.reqs);
1456	kfree(objp: uac->c_prm.reqs);
1457	kfree(objp: uac->p_prm.rbuf);
1458	kfree(objp: uac->c_prm.rbuf);
1459	kfree(objp: uac);
1460	}
1461	EXPORT_SYMBOL_GPL(g_audio_cleanup);
1462
1463	MODULE_LICENSE("GPL");
1464	MODULE_DESCRIPTION("USB gadget \"ALSA sound card\" utilities");
1465	MODULE_AUTHOR("Ruslan Bilovol");
1466