1/*
2 * f_audio.c -- USB Audio class function driver
3  *
4 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
5 * Copyright (C) 2008 Analog Devices, Inc
6 *
7 * Enter bugs at http://blackfin.uclinux.org/
8 *
9 * Licensed under the GPL-2 or later.
10 */
11
12#include <linux/slab.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/device.h>
16#include <linux/atomic.h>
17
18#include "u_uac1.h"
19
20static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
21static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
22
23/*
24 * DESCRIPTORS ... most are static, but strings and full
25 * configuration descriptors are built on demand.
26 */
27
28/*
29 * We have two interfaces- AudioControl and AudioStreaming
30 * TODO: only supcard playback currently
31 */
32#define F_AUDIO_AC_INTERFACE	0
33#define F_AUDIO_AS_INTERFACE	1
34#define F_AUDIO_NUM_INTERFACES	1
35
36/* B.3.1  Standard AC Interface Descriptor */
37static struct usb_interface_descriptor ac_interface_desc = {
38	.bLength =		USB_DT_INTERFACE_SIZE,
39	.bDescriptorType =	USB_DT_INTERFACE,
40	.bNumEndpoints =	0,
41	.bInterfaceClass =	USB_CLASS_AUDIO,
42	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOCONTROL,
43};
44
45/*
46 * The number of AudioStreaming and MIDIStreaming interfaces
47 * in the Audio Interface Collection
48 */
49DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
50
51#define UAC_DT_AC_HEADER_LENGTH	UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
52/* 1 input terminal, 1 output terminal and 1 feature unit */
53#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
54	+ UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
55/* B.3.2  Class-Specific AC Interface Descriptor */
56static struct uac1_ac_header_descriptor_1 ac_header_desc = {
57	.bLength =		UAC_DT_AC_HEADER_LENGTH,
58	.bDescriptorType =	USB_DT_CS_INTERFACE,
59	.bDescriptorSubtype =	UAC_HEADER,
60	.bcdADC =		__constant_cpu_to_le16(0x0100),
61	.wTotalLength =		__constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH),
62	.bInCollection =	F_AUDIO_NUM_INTERFACES,
63	.baInterfaceNr = {
64	/* Interface number of the first AudioStream interface */
65		[0] =		1,
66	}
67};
68
69#define INPUT_TERMINAL_ID	1
70static struct uac_input_terminal_descriptor input_terminal_desc = {
71	.bLength =		UAC_DT_INPUT_TERMINAL_SIZE,
72	.bDescriptorType =	USB_DT_CS_INTERFACE,
73	.bDescriptorSubtype =	UAC_INPUT_TERMINAL,
74	.bTerminalID =		INPUT_TERMINAL_ID,
75	.wTerminalType =	UAC_TERMINAL_STREAMING,
76	.bAssocTerminal =	0,
77	.wChannelConfig =	0x3,
78};
79
80DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
81
82#define FEATURE_UNIT_ID		2
83static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
84	.bLength		= UAC_DT_FEATURE_UNIT_SIZE(0),
85	.bDescriptorType	= USB_DT_CS_INTERFACE,
86	.bDescriptorSubtype	= UAC_FEATURE_UNIT,
87	.bUnitID		= FEATURE_UNIT_ID,
88	.bSourceID		= INPUT_TERMINAL_ID,
89	.bControlSize		= 2,
90	.bmaControls[0]		= (UAC_FU_MUTE | UAC_FU_VOLUME),
91};
92
93static struct usb_audio_control mute_control = {
94	.list = LIST_HEAD_INIT(mute_control.list),
95	.name = "Mute Control",
96	.type = UAC_FU_MUTE,
97	/* Todo: add real Mute control code */
98	.set = generic_set_cmd,
99	.get = generic_get_cmd,
100};
101
102static struct usb_audio_control volume_control = {
103	.list = LIST_HEAD_INIT(volume_control.list),
104	.name = "Volume Control",
105	.type = UAC_FU_VOLUME,
106	/* Todo: add real Volume control code */
107	.set = generic_set_cmd,
108	.get = generic_get_cmd,
109};
110
111static struct usb_audio_control_selector feature_unit = {
112	.list = LIST_HEAD_INIT(feature_unit.list),
113	.id = FEATURE_UNIT_ID,
114	.name = "Mute & Volume Control",
115	.type = UAC_FEATURE_UNIT,
116	.desc = (struct usb_descriptor_header *)&feature_unit_desc,
117};
118
119#define OUTPUT_TERMINAL_ID	3
120static struct uac1_output_terminal_descriptor output_terminal_desc = {
121	.bLength		= UAC_DT_OUTPUT_TERMINAL_SIZE,
122	.bDescriptorType	= USB_DT_CS_INTERFACE,
123	.bDescriptorSubtype	= UAC_OUTPUT_TERMINAL,
124	.bTerminalID		= OUTPUT_TERMINAL_ID,
125	.wTerminalType		= UAC_OUTPUT_TERMINAL_SPEAKER,
126	.bAssocTerminal		= FEATURE_UNIT_ID,
127	.bSourceID		= FEATURE_UNIT_ID,
128};
129
130/* B.4.1  Standard AS Interface Descriptor */
131static struct usb_interface_descriptor as_interface_alt_0_desc = {
132	.bLength =		USB_DT_INTERFACE_SIZE,
133	.bDescriptorType =	USB_DT_INTERFACE,
134	.bAlternateSetting =	0,
135	.bNumEndpoints =	0,
136	.bInterfaceClass =	USB_CLASS_AUDIO,
137	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
138};
139
140static struct usb_interface_descriptor as_interface_alt_1_desc = {
141	.bLength =		USB_DT_INTERFACE_SIZE,
142	.bDescriptorType =	USB_DT_INTERFACE,
143	.bAlternateSetting =	1,
144	.bNumEndpoints =	1,
145	.bInterfaceClass =	USB_CLASS_AUDIO,
146	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
147};
148
149/* B.4.2  Class-Specific AS Interface Descriptor */
150static struct uac1_as_header_descriptor as_header_desc = {
151	.bLength =		UAC_DT_AS_HEADER_SIZE,
152	.bDescriptorType =	USB_DT_CS_INTERFACE,
153	.bDescriptorSubtype =	UAC_AS_GENERAL,
154	.bTerminalLink =	INPUT_TERMINAL_ID,
155	.bDelay =		1,
156	.wFormatTag =		UAC_FORMAT_TYPE_I_PCM,
157};
158
159DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
160
161static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
162	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
163	.bDescriptorType =	USB_DT_CS_INTERFACE,
164	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
165	.bFormatType =		UAC_FORMAT_TYPE_I,
166	.bSubframeSize =	2,
167	.bBitResolution =	16,
168	.bSamFreqType =		1,
169};
170
171/* Standard ISO OUT Endpoint Descriptor */
172static struct usb_endpoint_descriptor as_out_ep_desc  = {
173	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
174	.bDescriptorType =	USB_DT_ENDPOINT,
175	.bEndpointAddress =	USB_DIR_OUT,
176	.bmAttributes =		USB_ENDPOINT_SYNC_ADAPTIVE
177				| USB_ENDPOINT_XFER_ISOC,
178	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
179	.bInterval =		4,
180};
181
182/* Class-specific AS ISO OUT Endpoint Descriptor */
183static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
184	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
185	.bDescriptorType =	USB_DT_CS_ENDPOINT,
186	.bDescriptorSubtype =	UAC_EP_GENERAL,
187	.bmAttributes = 	1,
188	.bLockDelayUnits =	1,
189	.wLockDelay =		__constant_cpu_to_le16(1),
190};
191
192static struct usb_descriptor_header *f_audio_desc[] = {
193	(struct usb_descriptor_header *)&ac_interface_desc,
194	(struct usb_descriptor_header *)&ac_header_desc,
195
196	(struct usb_descriptor_header *)&input_terminal_desc,
197	(struct usb_descriptor_header *)&output_terminal_desc,
198	(struct usb_descriptor_header *)&feature_unit_desc,
199
200	(struct usb_descriptor_header *)&as_interface_alt_0_desc,
201	(struct usb_descriptor_header *)&as_interface_alt_1_desc,
202	(struct usb_descriptor_header *)&as_header_desc,
203
204	(struct usb_descriptor_header *)&as_type_i_desc,
205
206	(struct usb_descriptor_header *)&as_out_ep_desc,
207	(struct usb_descriptor_header *)&as_iso_out_desc,
208	NULL,
209};
210
211enum {
212	STR_AC_IF,
213	STR_INPUT_TERMINAL,
214	STR_INPUT_TERMINAL_CH_NAMES,
215	STR_FEAT_DESC_0,
216	STR_OUTPUT_TERMINAL,
217	STR_AS_IF_ALT0,
218	STR_AS_IF_ALT1,
219};
220
221static struct usb_string strings_uac1[] = {
222	[STR_AC_IF].s = "AC Interface",
223	[STR_INPUT_TERMINAL].s = "Input terminal",
224	[STR_INPUT_TERMINAL_CH_NAMES].s = "Channels",
225	[STR_FEAT_DESC_0].s = "Volume control & mute",
226	[STR_OUTPUT_TERMINAL].s = "Output terminal",
227	[STR_AS_IF_ALT0].s = "AS Interface",
228	[STR_AS_IF_ALT1].s = "AS Interface",
229	{ },
230};
231
232static struct usb_gadget_strings str_uac1 = {
233	.language = 0x0409,	/* en-us */
234	.strings = strings_uac1,
235};
236
237static struct usb_gadget_strings *uac1_strings[] = {
238	&str_uac1,
239	NULL,
240};
241
242/*
243 * This function is an ALSA sound card following USB Audio Class Spec 1.0.
244 */
245
246/*-------------------------------------------------------------------------*/
247struct f_audio_buf {
248	u8 *buf;
249	int actual;
250	struct list_head list;
251};
252
253static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
254{
255	struct f_audio_buf *copy_buf;
256
257	copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
258	if (!copy_buf)
259		return ERR_PTR(-ENOMEM);
260
261	copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
262	if (!copy_buf->buf) {
263		kfree(copy_buf);
264		return ERR_PTR(-ENOMEM);
265	}
266
267	return copy_buf;
268}
269
270static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
271{
272	kfree(audio_buf->buf);
273	kfree(audio_buf);
274}
275/*-------------------------------------------------------------------------*/
276
277struct f_audio {
278	struct gaudio			card;
279
280	/* endpoints handle full and/or high speeds */
281	struct usb_ep			*out_ep;
282
283	spinlock_t			lock;
284	struct f_audio_buf *copy_buf;
285	struct work_struct playback_work;
286	struct list_head play_queue;
287
288	/* Control Set command */
289	struct list_head cs;
290	u8 set_cmd;
291	struct usb_audio_control *set_con;
292};
293
294static inline struct f_audio *func_to_audio(struct usb_function *f)
295{
296	return container_of(f, struct f_audio, card.func);
297}
298
299/*-------------------------------------------------------------------------*/
300
301static void f_audio_playback_work(struct work_struct *data)
302{
303	struct f_audio *audio = container_of(data, struct f_audio,
304					playback_work);
305	struct f_audio_buf *play_buf;
306
307	spin_lock_irq(&audio->lock);
308	if (list_empty(&audio->play_queue)) {
309		spin_unlock_irq(&audio->lock);
310		return;
311	}
312	play_buf = list_first_entry(&audio->play_queue,
313			struct f_audio_buf, list);
314	list_del(&play_buf->list);
315	spin_unlock_irq(&audio->lock);
316
317	u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
318	f_audio_buffer_free(play_buf);
319}
320
321static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
322{
323	struct f_audio *audio = req->context;
324	struct usb_composite_dev *cdev = audio->card.func.config->cdev;
325	struct f_audio_buf *copy_buf = audio->copy_buf;
326	struct f_uac1_opts *opts;
327	int audio_buf_size;
328	int err;
329
330	opts = container_of(audio->card.func.fi, struct f_uac1_opts,
331			    func_inst);
332	audio_buf_size = opts->audio_buf_size;
333
334	if (!copy_buf)
335		return -EINVAL;
336
337	/* Copy buffer is full, add it to the play_queue */
338	if (audio_buf_size - copy_buf->actual < req->actual) {
339		list_add_tail(&copy_buf->list, &audio->play_queue);
340		schedule_work(&audio->playback_work);
341		copy_buf = f_audio_buffer_alloc(audio_buf_size);
342		if (IS_ERR(copy_buf))
343			return -ENOMEM;
344	}
345
346	memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
347	copy_buf->actual += req->actual;
348	audio->copy_buf = copy_buf;
349
350	err = usb_ep_queue(ep, req, GFP_ATOMIC);
351	if (err)
352		ERROR(cdev, "%s queue req: %d\n", ep->name, err);
353
354	return 0;
355
356}
357
358static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
359{
360	struct f_audio *audio = req->context;
361	int status = req->status;
362	u32 data = 0;
363	struct usb_ep *out_ep = audio->out_ep;
364
365	switch (status) {
366
367	case 0:				/* normal completion? */
368		if (ep == out_ep)
369			f_audio_out_ep_complete(ep, req);
370		else if (audio->set_con) {
371			memcpy(&data, req->buf, req->length);
372			audio->set_con->set(audio->set_con, audio->set_cmd,
373					le16_to_cpu(data));
374			audio->set_con = NULL;
375		}
376		break;
377	default:
378		break;
379	}
380}
381
382static int audio_set_intf_req(struct usb_function *f,
383		const struct usb_ctrlrequest *ctrl)
384{
385	struct f_audio		*audio = func_to_audio(f);
386	struct usb_composite_dev *cdev = f->config->cdev;
387	struct usb_request	*req = cdev->req;
388	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
389	u16			len = le16_to_cpu(ctrl->wLength);
390	u16			w_value = le16_to_cpu(ctrl->wValue);
391	u8			con_sel = (w_value >> 8) & 0xFF;
392	u8			cmd = (ctrl->bRequest & 0x0F);
393	struct usb_audio_control_selector *cs;
394	struct usb_audio_control *con;
395
396	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
397			ctrl->bRequest, w_value, len, id);
398
399	list_for_each_entry(cs, &audio->cs, list) {
400		if (cs->id == id) {
401			list_for_each_entry(con, &cs->control, list) {
402				if (con->type == con_sel) {
403					audio->set_con = con;
404					break;
405				}
406			}
407			break;
408		}
409	}
410
411	audio->set_cmd = cmd;
412	req->context = audio;
413	req->complete = f_audio_complete;
414
415	return len;
416}
417
418static int audio_get_intf_req(struct usb_function *f,
419		const struct usb_ctrlrequest *ctrl)
420{
421	struct f_audio		*audio = func_to_audio(f);
422	struct usb_composite_dev *cdev = f->config->cdev;
423	struct usb_request	*req = cdev->req;
424	int			value = -EOPNOTSUPP;
425	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
426	u16			len = le16_to_cpu(ctrl->wLength);
427	u16			w_value = le16_to_cpu(ctrl->wValue);
428	u8			con_sel = (w_value >> 8) & 0xFF;
429	u8			cmd = (ctrl->bRequest & 0x0F);
430	struct usb_audio_control_selector *cs;
431	struct usb_audio_control *con;
432
433	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
434			ctrl->bRequest, w_value, len, id);
435
436	list_for_each_entry(cs, &audio->cs, list) {
437		if (cs->id == id) {
438			list_for_each_entry(con, &cs->control, list) {
439				if (con->type == con_sel && con->get) {
440					value = con->get(con, cmd);
441					break;
442				}
443			}
444			break;
445		}
446	}
447
448	req->context = audio;
449	req->complete = f_audio_complete;
450	len = min_t(size_t, sizeof(value), len);
451	memcpy(req->buf, &value, len);
452
453	return len;
454}
455
456static int audio_set_endpoint_req(struct usb_function *f,
457		const struct usb_ctrlrequest *ctrl)
458{
459	struct usb_composite_dev *cdev = f->config->cdev;
460	int			value = -EOPNOTSUPP;
461	u16			ep = le16_to_cpu(ctrl->wIndex);
462	u16			len = le16_to_cpu(ctrl->wLength);
463	u16			w_value = le16_to_cpu(ctrl->wValue);
464
465	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
466			ctrl->bRequest, w_value, len, ep);
467
468	switch (ctrl->bRequest) {
469	case UAC_SET_CUR:
470		value = len;
471		break;
472
473	case UAC_SET_MIN:
474		break;
475
476	case UAC_SET_MAX:
477		break;
478
479	case UAC_SET_RES:
480		break;
481
482	case UAC_SET_MEM:
483		break;
484
485	default:
486		break;
487	}
488
489	return value;
490}
491
492static int audio_get_endpoint_req(struct usb_function *f,
493		const struct usb_ctrlrequest *ctrl)
494{
495	struct usb_composite_dev *cdev = f->config->cdev;
496	int value = -EOPNOTSUPP;
497	u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
498	u16 len = le16_to_cpu(ctrl->wLength);
499	u16 w_value = le16_to_cpu(ctrl->wValue);
500
501	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
502			ctrl->bRequest, w_value, len, ep);
503
504	switch (ctrl->bRequest) {
505	case UAC_GET_CUR:
506	case UAC_GET_MIN:
507	case UAC_GET_MAX:
508	case UAC_GET_RES:
509		value = len;
510		break;
511	case UAC_GET_MEM:
512		break;
513	default:
514		break;
515	}
516
517	return value;
518}
519
520static int
521f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
522{
523	struct usb_composite_dev *cdev = f->config->cdev;
524	struct usb_request	*req = cdev->req;
525	int			value = -EOPNOTSUPP;
526	u16			w_index = le16_to_cpu(ctrl->wIndex);
527	u16			w_value = le16_to_cpu(ctrl->wValue);
528	u16			w_length = le16_to_cpu(ctrl->wLength);
529
530	/* composite driver infrastructure handles everything; interface
531	 * activation uses set_alt().
532	 */
533	switch (ctrl->bRequestType) {
534	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
535		value = audio_set_intf_req(f, ctrl);
536		break;
537
538	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
539		value = audio_get_intf_req(f, ctrl);
540		break;
541
542	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
543		value = audio_set_endpoint_req(f, ctrl);
544		break;
545
546	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
547		value = audio_get_endpoint_req(f, ctrl);
548		break;
549
550	default:
551		ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
552			ctrl->bRequestType, ctrl->bRequest,
553			w_value, w_index, w_length);
554	}
555
556	/* respond with data transfer or status phase? */
557	if (value >= 0) {
558		DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
559			ctrl->bRequestType, ctrl->bRequest,
560			w_value, w_index, w_length);
561		req->zero = 0;
562		req->length = value;
563		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
564		if (value < 0)
565			ERROR(cdev, "audio response on err %d\n", value);
566	}
567
568	/* device either stalls (value < 0) or reports success */
569	return value;
570}
571
572static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
573{
574	struct f_audio		*audio = func_to_audio(f);
575	struct usb_composite_dev *cdev = f->config->cdev;
576	struct usb_ep *out_ep = audio->out_ep;
577	struct usb_request *req;
578	struct f_uac1_opts *opts;
579	int req_buf_size, req_count, audio_buf_size;
580	int i = 0, err = 0;
581
582	DBG(cdev, "intf %d, alt %d\n", intf, alt);
583
584	opts = container_of(f->fi, struct f_uac1_opts, func_inst);
585	req_buf_size = opts->req_buf_size;
586	req_count = opts->req_count;
587	audio_buf_size = opts->audio_buf_size;
588
589	if (intf == 1) {
590		if (alt == 1) {
591			err = config_ep_by_speed(cdev->gadget, f, out_ep);
592			if (err)
593				return err;
594
595			usb_ep_enable(out_ep);
596			out_ep->driver_data = audio;
597			audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
598			if (IS_ERR(audio->copy_buf))
599				return -ENOMEM;
600
601			/*
602			 * allocate a bunch of read buffers
603			 * and queue them all at once.
604			 */
605			for (i = 0; i < req_count && err == 0; i++) {
606				req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
607				if (req) {
608					req->buf = kzalloc(req_buf_size,
609							GFP_ATOMIC);
610					if (req->buf) {
611						req->length = req_buf_size;
612						req->context = audio;
613						req->complete =
614							f_audio_complete;
615						err = usb_ep_queue(out_ep,
616							req, GFP_ATOMIC);
617						if (err)
618							ERROR(cdev,
619							"%s queue req: %d\n",
620							out_ep->name, err);
621					} else
622						err = -ENOMEM;
623				} else
624					err = -ENOMEM;
625			}
626
627		} else {
628			struct f_audio_buf *copy_buf = audio->copy_buf;
629			if (copy_buf) {
630				list_add_tail(&copy_buf->list,
631						&audio->play_queue);
632				schedule_work(&audio->playback_work);
633			}
634		}
635	}
636
637	return err;
638}
639
640static void f_audio_disable(struct usb_function *f)
641{
642	return;
643}
644
645/*-------------------------------------------------------------------------*/
646
647static void f_audio_build_desc(struct f_audio *audio)
648{
649	struct gaudio *card = &audio->card;
650	u8 *sam_freq;
651	int rate;
652
653	/* Set channel numbers */
654	input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
655	as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
656
657	/* Set sample rates */
658	rate = u_audio_get_playback_rate(card);
659	sam_freq = as_type_i_desc.tSamFreq[0];
660	memcpy(sam_freq, &rate, 3);
661
662	/* Todo: Set Sample bits and other parameters */
663
664	return;
665}
666
667/* audio function driver setup/binding */
668static int
669f_audio_bind(struct usb_configuration *c, struct usb_function *f)
670{
671	struct usb_composite_dev *cdev = c->cdev;
672	struct f_audio		*audio = func_to_audio(f);
673	struct usb_string	*us;
674	int			status;
675	struct usb_ep		*ep = NULL;
676	struct f_uac1_opts	*audio_opts;
677
678	audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst);
679	audio->card.gadget = c->cdev->gadget;
680	/* set up ASLA audio devices */
681	if (!audio_opts->bound) {
682		status = gaudio_setup(&audio->card);
683		if (status < 0)
684			return status;
685		audio_opts->bound = true;
686	}
687	us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
688	if (IS_ERR(us))
689		return PTR_ERR(us);
690	ac_interface_desc.iInterface = us[STR_AC_IF].id;
691	input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
692	input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
693	feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
694	output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
695	as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
696	as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
697
698
699	f_audio_build_desc(audio);
700
701	/* allocate instance-specific interface IDs, and patch descriptors */
702	status = usb_interface_id(c, f);
703	if (status < 0)
704		goto fail;
705	ac_interface_desc.bInterfaceNumber = status;
706
707	status = usb_interface_id(c, f);
708	if (status < 0)
709		goto fail;
710	as_interface_alt_0_desc.bInterfaceNumber = status;
711	as_interface_alt_1_desc.bInterfaceNumber = status;
712
713	status = -ENODEV;
714
715	/* allocate instance-specific endpoints */
716	ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
717	if (!ep)
718		goto fail;
719	audio->out_ep = ep;
720	audio->out_ep->desc = &as_out_ep_desc;
721	ep->driver_data = cdev;	/* claim */
722
723	status = -ENOMEM;
724
725	/* copy descriptors, and track endpoint copies */
726	status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL);
727	if (status)
728		goto fail;
729	return 0;
730
731fail:
732	gaudio_cleanup(&audio->card);
733	if (ep)
734		ep->driver_data = NULL;
735	return status;
736}
737
738/*-------------------------------------------------------------------------*/
739
740static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
741{
742	con->data[cmd] = value;
743
744	return 0;
745}
746
747static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
748{
749	return con->data[cmd];
750}
751
752/* Todo: add more control selecotor dynamically */
753static int control_selector_init(struct f_audio *audio)
754{
755	INIT_LIST_HEAD(&audio->cs);
756	list_add(&feature_unit.list, &audio->cs);
757
758	INIT_LIST_HEAD(&feature_unit.control);
759	list_add(&mute_control.list, &feature_unit.control);
760	list_add(&volume_control.list, &feature_unit.control);
761
762	volume_control.data[UAC__CUR] = 0xffc0;
763	volume_control.data[UAC__MIN] = 0xe3a0;
764	volume_control.data[UAC__MAX] = 0xfff0;
765	volume_control.data[UAC__RES] = 0x0030;
766
767	return 0;
768}
769
770static inline struct f_uac1_opts *to_f_uac1_opts(struct config_item *item)
771{
772	return container_of(to_config_group(item), struct f_uac1_opts,
773			    func_inst.group);
774}
775
776CONFIGFS_ATTR_STRUCT(f_uac1_opts);
777CONFIGFS_ATTR_OPS(f_uac1_opts);
778
779static void f_uac1_attr_release(struct config_item *item)
780{
781	struct f_uac1_opts *opts = to_f_uac1_opts(item);
782
783	usb_put_function_instance(&opts->func_inst);
784}
785
786static struct configfs_item_operations f_uac1_item_ops = {
787	.release	= f_uac1_attr_release,
788	.show_attribute	= f_uac1_opts_attr_show,
789	.store_attribute = f_uac1_opts_attr_store,
790};
791
792#define UAC1_INT_ATTRIBUTE(name)					\
793static ssize_t f_uac1_opts_##name##_show(struct f_uac1_opts *opts,	\
794					 char *page)			\
795{									\
796	int result;							\
797									\
798	mutex_lock(&opts->lock);					\
799	result = sprintf(page, "%u\n", opts->name);			\
800	mutex_unlock(&opts->lock);					\
801									\
802	return result;							\
803}									\
804									\
805static ssize_t f_uac1_opts_##name##_store(struct f_uac1_opts *opts,	\
806					  const char *page, size_t len)	\
807{									\
808	int ret;							\
809	u32 num;							\
810									\
811	mutex_lock(&opts->lock);					\
812	if (opts->refcnt) {						\
813		ret = -EBUSY;						\
814		goto end;						\
815	}								\
816									\
817	ret = kstrtou32(page, 0, &num);					\
818	if (ret)							\
819		goto end;						\
820									\
821	opts->name = num;						\
822	ret = len;							\
823									\
824end:									\
825	mutex_unlock(&opts->lock);					\
826	return ret;							\
827}									\
828									\
829static struct f_uac1_opts_attribute f_uac1_opts_##name =		\
830	__CONFIGFS_ATTR(name, S_IRUGO | S_IWUSR,			\
831			f_uac1_opts_##name##_show,			\
832			f_uac1_opts_##name##_store)
833
834UAC1_INT_ATTRIBUTE(req_buf_size);
835UAC1_INT_ATTRIBUTE(req_count);
836UAC1_INT_ATTRIBUTE(audio_buf_size);
837
838#define UAC1_STR_ATTRIBUTE(name)					\
839static ssize_t f_uac1_opts_##name##_show(struct f_uac1_opts *opts,	\
840					 char *page)			\
841{									\
842	int result;							\
843									\
844	mutex_lock(&opts->lock);					\
845	result = sprintf(page, "%s\n", opts->name);			\
846	mutex_unlock(&opts->lock);					\
847									\
848	return result;							\
849}									\
850									\
851static ssize_t f_uac1_opts_##name##_store(struct f_uac1_opts *opts,	\
852					  const char *page, size_t len)	\
853{									\
854	int ret = -EBUSY;						\
855	char *tmp;							\
856									\
857	mutex_lock(&opts->lock);					\
858	if (opts->refcnt)						\
859		goto end;						\
860									\
861	tmp = kstrndup(page, len, GFP_KERNEL);				\
862	if (tmp) {							\
863		ret = -ENOMEM;						\
864		goto end;						\
865	}								\
866	if (opts->name##_alloc)						\
867		kfree(opts->name);					\
868	opts->name##_alloc = true;					\
869	opts->name = tmp;						\
870	ret = len;							\
871									\
872end:									\
873	mutex_unlock(&opts->lock);					\
874	return ret;							\
875}									\
876									\
877static struct f_uac1_opts_attribute f_uac1_opts_##name =		\
878	__CONFIGFS_ATTR(name, S_IRUGO | S_IWUSR,			\
879			f_uac1_opts_##name##_show,			\
880			f_uac1_opts_##name##_store)
881
882UAC1_STR_ATTRIBUTE(fn_play);
883UAC1_STR_ATTRIBUTE(fn_cap);
884UAC1_STR_ATTRIBUTE(fn_cntl);
885
886static struct configfs_attribute *f_uac1_attrs[] = {
887	&f_uac1_opts_req_buf_size.attr,
888	&f_uac1_opts_req_count.attr,
889	&f_uac1_opts_audio_buf_size.attr,
890	&f_uac1_opts_fn_play.attr,
891	&f_uac1_opts_fn_cap.attr,
892	&f_uac1_opts_fn_cntl.attr,
893	NULL,
894};
895
896static struct config_item_type f_uac1_func_type = {
897	.ct_item_ops	= &f_uac1_item_ops,
898	.ct_attrs	= f_uac1_attrs,
899	.ct_owner	= THIS_MODULE,
900};
901
902static void f_audio_free_inst(struct usb_function_instance *f)
903{
904	struct f_uac1_opts *opts;
905
906	opts = container_of(f, struct f_uac1_opts, func_inst);
907	if (opts->fn_play_alloc)
908		kfree(opts->fn_play);
909	if (opts->fn_cap_alloc)
910		kfree(opts->fn_cap);
911	if (opts->fn_cntl_alloc)
912		kfree(opts->fn_cntl);
913	kfree(opts);
914}
915
916static struct usb_function_instance *f_audio_alloc_inst(void)
917{
918	struct f_uac1_opts *opts;
919
920	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
921	if (!opts)
922		return ERR_PTR(-ENOMEM);
923
924	mutex_init(&opts->lock);
925	opts->func_inst.free_func_inst = f_audio_free_inst;
926
927	config_group_init_type_name(&opts->func_inst.group, "",
928				    &f_uac1_func_type);
929
930	opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
931	opts->req_count = UAC1_REQ_COUNT;
932	opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
933	opts->fn_play = FILE_PCM_PLAYBACK;
934	opts->fn_cap = FILE_PCM_CAPTURE;
935	opts->fn_cntl = FILE_CONTROL;
936	return &opts->func_inst;
937}
938
939static void f_audio_free(struct usb_function *f)
940{
941	struct f_audio *audio = func_to_audio(f);
942	struct f_uac1_opts *opts;
943
944	gaudio_cleanup(&audio->card);
945	opts = container_of(f->fi, struct f_uac1_opts, func_inst);
946	kfree(audio);
947	mutex_lock(&opts->lock);
948	--opts->refcnt;
949	mutex_unlock(&opts->lock);
950}
951
952static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
953{
954	usb_free_all_descriptors(f);
955}
956
957static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
958{
959	struct f_audio *audio;
960	struct f_uac1_opts *opts;
961
962	/* allocate and initialize one new instance */
963	audio = kzalloc(sizeof(*audio), GFP_KERNEL);
964	if (!audio)
965		return ERR_PTR(-ENOMEM);
966
967	audio->card.func.name = "g_audio";
968
969	opts = container_of(fi, struct f_uac1_opts, func_inst);
970	mutex_lock(&opts->lock);
971	++opts->refcnt;
972	mutex_unlock(&opts->lock);
973	INIT_LIST_HEAD(&audio->play_queue);
974	spin_lock_init(&audio->lock);
975
976	audio->card.func.bind = f_audio_bind;
977	audio->card.func.unbind = f_audio_unbind;
978	audio->card.func.set_alt = f_audio_set_alt;
979	audio->card.func.setup = f_audio_setup;
980	audio->card.func.disable = f_audio_disable;
981	audio->card.func.free_func = f_audio_free;
982
983	control_selector_init(audio);
984
985	INIT_WORK(&audio->playback_work, f_audio_playback_work);
986
987	return &audio->card.func;
988}
989
990DECLARE_USB_FUNCTION_INIT(uac1, f_audio_alloc_inst, f_audio_alloc);
991MODULE_LICENSE("GPL");
992MODULE_AUTHOR("Bryan Wu");
993