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	2
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
45DECLARE_UAC_AC_HEADER_DESCRIPTOR(2);
46
47#define UAC_DT_AC_HEADER_LENGTH	UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
48/* 1 input terminal, 1 output terminal and 1 feature unit */
49#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
50	+ UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
51/* B.3.2  Class-Specific AC Interface Descriptor */
52static struct uac1_ac_header_descriptor_2 ac_header_desc = {
53	.bLength =		UAC_DT_AC_HEADER_LENGTH,
54	.bDescriptorType =	USB_DT_CS_INTERFACE,
55	.bDescriptorSubtype =	UAC_HEADER,
56	.bcdADC =		__constant_cpu_to_le16(0x0100),
57	.wTotalLength =		__constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH),
58	.bInCollection =	F_AUDIO_NUM_INTERFACES,
59	.baInterfaceNr = {
60		[0] =		F_AUDIO_AC_INTERFACE,
61		[1] =		F_AUDIO_AS_INTERFACE,
62	}
63};
64
65#define INPUT_TERMINAL_ID	1
66static struct uac_input_terminal_descriptor input_terminal_desc = {
67	.bLength =		UAC_DT_INPUT_TERMINAL_SIZE,
68	.bDescriptorType =	USB_DT_CS_INTERFACE,
69	.bDescriptorSubtype =	UAC_INPUT_TERMINAL,
70	.bTerminalID =		INPUT_TERMINAL_ID,
71	.wTerminalType =	UAC_TERMINAL_STREAMING,
72	.bAssocTerminal =	0,
73	.wChannelConfig =	0x3,
74};
75
76DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
77
78#define FEATURE_UNIT_ID		2
79static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
80	.bLength		= UAC_DT_FEATURE_UNIT_SIZE(0),
81	.bDescriptorType	= USB_DT_CS_INTERFACE,
82	.bDescriptorSubtype	= UAC_FEATURE_UNIT,
83	.bUnitID		= FEATURE_UNIT_ID,
84	.bSourceID		= INPUT_TERMINAL_ID,
85	.bControlSize		= 2,
86	.bmaControls[0]		= (UAC_FU_MUTE | UAC_FU_VOLUME),
87};
88
89static struct usb_audio_control mute_control = {
90	.list = LIST_HEAD_INIT(mute_control.list),
91	.name = "Mute Control",
92	.type = UAC_FU_MUTE,
93	/* Todo: add real Mute control code */
94	.set = generic_set_cmd,
95	.get = generic_get_cmd,
96};
97
98static struct usb_audio_control volume_control = {
99	.list = LIST_HEAD_INIT(volume_control.list),
100	.name = "Volume Control",
101	.type = UAC_FU_VOLUME,
102	/* Todo: add real Volume control code */
103	.set = generic_set_cmd,
104	.get = generic_get_cmd,
105};
106
107static struct usb_audio_control_selector feature_unit = {
108	.list = LIST_HEAD_INIT(feature_unit.list),
109	.id = FEATURE_UNIT_ID,
110	.name = "Mute & Volume Control",
111	.type = UAC_FEATURE_UNIT,
112	.desc = (struct usb_descriptor_header *)&feature_unit_desc,
113};
114
115#define OUTPUT_TERMINAL_ID	3
116static struct uac1_output_terminal_descriptor output_terminal_desc = {
117	.bLength		= UAC_DT_OUTPUT_TERMINAL_SIZE,
118	.bDescriptorType	= USB_DT_CS_INTERFACE,
119	.bDescriptorSubtype	= UAC_OUTPUT_TERMINAL,
120	.bTerminalID		= OUTPUT_TERMINAL_ID,
121	.wTerminalType		= UAC_OUTPUT_TERMINAL_SPEAKER,
122	.bAssocTerminal		= FEATURE_UNIT_ID,
123	.bSourceID		= FEATURE_UNIT_ID,
124};
125
126/* B.4.1  Standard AS Interface Descriptor */
127static struct usb_interface_descriptor as_interface_alt_0_desc = {
128	.bLength =		USB_DT_INTERFACE_SIZE,
129	.bDescriptorType =	USB_DT_INTERFACE,
130	.bAlternateSetting =	0,
131	.bNumEndpoints =	0,
132	.bInterfaceClass =	USB_CLASS_AUDIO,
133	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
134};
135
136static struct usb_interface_descriptor as_interface_alt_1_desc = {
137	.bLength =		USB_DT_INTERFACE_SIZE,
138	.bDescriptorType =	USB_DT_INTERFACE,
139	.bAlternateSetting =	1,
140	.bNumEndpoints =	1,
141	.bInterfaceClass =	USB_CLASS_AUDIO,
142	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
143};
144
145/* B.4.2  Class-Specific AS Interface Descriptor */
146static struct uac1_as_header_descriptor as_header_desc = {
147	.bLength =		UAC_DT_AS_HEADER_SIZE,
148	.bDescriptorType =	USB_DT_CS_INTERFACE,
149	.bDescriptorSubtype =	UAC_AS_GENERAL,
150	.bTerminalLink =	INPUT_TERMINAL_ID,
151	.bDelay =		1,
152	.wFormatTag =		UAC_FORMAT_TYPE_I_PCM,
153};
154
155DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
156
157static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
158	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
159	.bDescriptorType =	USB_DT_CS_INTERFACE,
160	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
161	.bFormatType =		UAC_FORMAT_TYPE_I,
162	.bSubframeSize =	2,
163	.bBitResolution =	16,
164	.bSamFreqType =		1,
165};
166
167/* Standard ISO OUT Endpoint Descriptor */
168static struct usb_endpoint_descriptor as_out_ep_desc  = {
169	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
170	.bDescriptorType =	USB_DT_ENDPOINT,
171	.bEndpointAddress =	USB_DIR_OUT,
172	.bmAttributes =		USB_ENDPOINT_SYNC_ADAPTIVE
173				| USB_ENDPOINT_XFER_ISOC,
174	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
175	.bInterval =		4,
176};
177
178/* Class-specific AS ISO OUT Endpoint Descriptor */
179static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
180	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
181	.bDescriptorType =	USB_DT_CS_ENDPOINT,
182	.bDescriptorSubtype =	UAC_EP_GENERAL,
183	.bmAttributes = 	1,
184	.bLockDelayUnits =	1,
185	.wLockDelay =		__constant_cpu_to_le16(1),
186};
187
188static struct usb_descriptor_header *f_audio_desc[] = {
189	(struct usb_descriptor_header *)&ac_interface_desc,
190	(struct usb_descriptor_header *)&ac_header_desc,
191
192	(struct usb_descriptor_header *)&input_terminal_desc,
193	(struct usb_descriptor_header *)&output_terminal_desc,
194	(struct usb_descriptor_header *)&feature_unit_desc,
195
196	(struct usb_descriptor_header *)&as_interface_alt_0_desc,
197	(struct usb_descriptor_header *)&as_interface_alt_1_desc,
198	(struct usb_descriptor_header *)&as_header_desc,
199
200	(struct usb_descriptor_header *)&as_type_i_desc,
201
202	(struct usb_descriptor_header *)&as_out_ep_desc,
203	(struct usb_descriptor_header *)&as_iso_out_desc,
204	NULL,
205};
206
207enum {
208	STR_AC_IF,
209	STR_INPUT_TERMINAL,
210	STR_INPUT_TERMINAL_CH_NAMES,
211	STR_FEAT_DESC_0,
212	STR_OUTPUT_TERMINAL,
213	STR_AS_IF_ALT0,
214	STR_AS_IF_ALT1,
215};
216
217static struct usb_string strings_uac1[] = {
218	[STR_AC_IF].s = "AC Interface",
219	[STR_INPUT_TERMINAL].s = "Input terminal",
220	[STR_INPUT_TERMINAL_CH_NAMES].s = "Channels",
221	[STR_FEAT_DESC_0].s = "Volume control & mute",
222	[STR_OUTPUT_TERMINAL].s = "Output terminal",
223	[STR_AS_IF_ALT0].s = "AS Interface",
224	[STR_AS_IF_ALT1].s = "AS Interface",
225	{ },
226};
227
228static struct usb_gadget_strings str_uac1 = {
229	.language = 0x0409,	/* en-us */
230	.strings = strings_uac1,
231};
232
233static struct usb_gadget_strings *uac1_strings[] = {
234	&str_uac1,
235	NULL,
236};
237
238/*
239 * This function is an ALSA sound card following USB Audio Class Spec 1.0.
240 */
241
242/*-------------------------------------------------------------------------*/
243struct f_audio_buf {
244	u8 *buf;
245	int actual;
246	struct list_head list;
247};
248
249static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
250{
251	struct f_audio_buf *copy_buf;
252
253	copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
254	if (!copy_buf)
255		return ERR_PTR(-ENOMEM);
256
257	copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
258	if (!copy_buf->buf) {
259		kfree(copy_buf);
260		return ERR_PTR(-ENOMEM);
261	}
262
263	return copy_buf;
264}
265
266static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
267{
268	kfree(audio_buf->buf);
269	kfree(audio_buf);
270}
271/*-------------------------------------------------------------------------*/
272
273struct f_audio {
274	struct gaudio			card;
275
276	/* endpoints handle full and/or high speeds */
277	struct usb_ep			*out_ep;
278
279	spinlock_t			lock;
280	struct f_audio_buf *copy_buf;
281	struct work_struct playback_work;
282	struct list_head play_queue;
283
284	/* Control Set command */
285	struct list_head cs;
286	u8 set_cmd;
287	struct usb_audio_control *set_con;
288};
289
290static inline struct f_audio *func_to_audio(struct usb_function *f)
291{
292	return container_of(f, struct f_audio, card.func);
293}
294
295/*-------------------------------------------------------------------------*/
296
297static void f_audio_playback_work(struct work_struct *data)
298{
299	struct f_audio *audio = container_of(data, struct f_audio,
300					playback_work);
301	struct f_audio_buf *play_buf;
302
303	spin_lock_irq(&audio->lock);
304	if (list_empty(&audio->play_queue)) {
305		spin_unlock_irq(&audio->lock);
306		return;
307	}
308	play_buf = list_first_entry(&audio->play_queue,
309			struct f_audio_buf, list);
310	list_del(&play_buf->list);
311	spin_unlock_irq(&audio->lock);
312
313	u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
314	f_audio_buffer_free(play_buf);
315}
316
317static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
318{
319	struct f_audio *audio = req->context;
320	struct usb_composite_dev *cdev = audio->card.func.config->cdev;
321	struct f_audio_buf *copy_buf = audio->copy_buf;
322	struct f_uac1_opts *opts;
323	int audio_buf_size;
324	int err;
325
326	opts = container_of(audio->card.func.fi, struct f_uac1_opts,
327			    func_inst);
328	audio_buf_size = opts->audio_buf_size;
329
330	if (!copy_buf)
331		return -EINVAL;
332
333	/* Copy buffer is full, add it to the play_queue */
334	if (audio_buf_size - copy_buf->actual < req->actual) {
335		list_add_tail(&copy_buf->list, &audio->play_queue);
336		schedule_work(&audio->playback_work);
337		copy_buf = f_audio_buffer_alloc(audio_buf_size);
338		if (IS_ERR(copy_buf))
339			return -ENOMEM;
340	}
341
342	memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
343	copy_buf->actual += req->actual;
344	audio->copy_buf = copy_buf;
345
346	err = usb_ep_queue(ep, req, GFP_ATOMIC);
347	if (err)
348		ERROR(cdev, "%s queue req: %d\n", ep->name, err);
349
350	return 0;
351
352}
353
354static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
355{
356	struct f_audio *audio = req->context;
357	int status = req->status;
358	u32 data = 0;
359	struct usb_ep *out_ep = audio->out_ep;
360
361	switch (status) {
362
363	case 0:				/* normal completion? */
364		if (ep == out_ep)
365			f_audio_out_ep_complete(ep, req);
366		else if (audio->set_con) {
367			memcpy(&data, req->buf, req->length);
368			audio->set_con->set(audio->set_con, audio->set_cmd,
369					le16_to_cpu(data));
370			audio->set_con = NULL;
371		}
372		break;
373	default:
374		break;
375	}
376}
377
378static int audio_set_intf_req(struct usb_function *f,
379		const struct usb_ctrlrequest *ctrl)
380{
381	struct f_audio		*audio = func_to_audio(f);
382	struct usb_composite_dev *cdev = f->config->cdev;
383	struct usb_request	*req = cdev->req;
384	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
385	u16			len = le16_to_cpu(ctrl->wLength);
386	u16			w_value = le16_to_cpu(ctrl->wValue);
387	u8			con_sel = (w_value >> 8) & 0xFF;
388	u8			cmd = (ctrl->bRequest & 0x0F);
389	struct usb_audio_control_selector *cs;
390	struct usb_audio_control *con;
391
392	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
393			ctrl->bRequest, w_value, len, id);
394
395	list_for_each_entry(cs, &audio->cs, list) {
396		if (cs->id == id) {
397			list_for_each_entry(con, &cs->control, list) {
398				if (con->type == con_sel) {
399					audio->set_con = con;
400					break;
401				}
402			}
403			break;
404		}
405	}
406
407	audio->set_cmd = cmd;
408	req->context = audio;
409	req->complete = f_audio_complete;
410
411	return len;
412}
413
414static int audio_get_intf_req(struct usb_function *f,
415		const struct usb_ctrlrequest *ctrl)
416{
417	struct f_audio		*audio = func_to_audio(f);
418	struct usb_composite_dev *cdev = f->config->cdev;
419	struct usb_request	*req = cdev->req;
420	int			value = -EOPNOTSUPP;
421	u8			id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
422	u16			len = le16_to_cpu(ctrl->wLength);
423	u16			w_value = le16_to_cpu(ctrl->wValue);
424	u8			con_sel = (w_value >> 8) & 0xFF;
425	u8			cmd = (ctrl->bRequest & 0x0F);
426	struct usb_audio_control_selector *cs;
427	struct usb_audio_control *con;
428
429	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
430			ctrl->bRequest, w_value, len, id);
431
432	list_for_each_entry(cs, &audio->cs, list) {
433		if (cs->id == id) {
434			list_for_each_entry(con, &cs->control, list) {
435				if (con->type == con_sel && con->get) {
436					value = con->get(con, cmd);
437					break;
438				}
439			}
440			break;
441		}
442	}
443
444	req->context = audio;
445	req->complete = f_audio_complete;
446	len = min_t(size_t, sizeof(value), len);
447	memcpy(req->buf, &value, len);
448
449	return len;
450}
451
452static int audio_set_endpoint_req(struct usb_function *f,
453		const struct usb_ctrlrequest *ctrl)
454{
455	struct usb_composite_dev *cdev = f->config->cdev;
456	int			value = -EOPNOTSUPP;
457	u16			ep = le16_to_cpu(ctrl->wIndex);
458	u16			len = le16_to_cpu(ctrl->wLength);
459	u16			w_value = le16_to_cpu(ctrl->wValue);
460
461	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
462			ctrl->bRequest, w_value, len, ep);
463
464	switch (ctrl->bRequest) {
465	case UAC_SET_CUR:
466		value = len;
467		break;
468
469	case UAC_SET_MIN:
470		break;
471
472	case UAC_SET_MAX:
473		break;
474
475	case UAC_SET_RES:
476		break;
477
478	case UAC_SET_MEM:
479		break;
480
481	default:
482		break;
483	}
484
485	return value;
486}
487
488static int audio_get_endpoint_req(struct usb_function *f,
489		const struct usb_ctrlrequest *ctrl)
490{
491	struct usb_composite_dev *cdev = f->config->cdev;
492	int value = -EOPNOTSUPP;
493	u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
494	u16 len = le16_to_cpu(ctrl->wLength);
495	u16 w_value = le16_to_cpu(ctrl->wValue);
496
497	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
498			ctrl->bRequest, w_value, len, ep);
499
500	switch (ctrl->bRequest) {
501	case UAC_GET_CUR:
502	case UAC_GET_MIN:
503	case UAC_GET_MAX:
504	case UAC_GET_RES:
505		value = len;
506		break;
507	case UAC_GET_MEM:
508		break;
509	default:
510		break;
511	}
512
513	return value;
514}
515
516static int
517f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
518{
519	struct usb_composite_dev *cdev = f->config->cdev;
520	struct usb_request	*req = cdev->req;
521	int			value = -EOPNOTSUPP;
522	u16			w_index = le16_to_cpu(ctrl->wIndex);
523	u16			w_value = le16_to_cpu(ctrl->wValue);
524	u16			w_length = le16_to_cpu(ctrl->wLength);
525
526	/* composite driver infrastructure handles everything; interface
527	 * activation uses set_alt().
528	 */
529	switch (ctrl->bRequestType) {
530	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
531		value = audio_set_intf_req(f, ctrl);
532		break;
533
534	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
535		value = audio_get_intf_req(f, ctrl);
536		break;
537
538	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
539		value = audio_set_endpoint_req(f, ctrl);
540		break;
541
542	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
543		value = audio_get_endpoint_req(f, ctrl);
544		break;
545
546	default:
547		ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
548			ctrl->bRequestType, ctrl->bRequest,
549			w_value, w_index, w_length);
550	}
551
552	/* respond with data transfer or status phase? */
553	if (value >= 0) {
554		DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
555			ctrl->bRequestType, ctrl->bRequest,
556			w_value, w_index, w_length);
557		req->zero = 0;
558		req->length = value;
559		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
560		if (value < 0)
561			ERROR(cdev, "audio response on err %d\n", value);
562	}
563
564	/* device either stalls (value < 0) or reports success */
565	return value;
566}
567
568static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
569{
570	struct f_audio		*audio = func_to_audio(f);
571	struct usb_composite_dev *cdev = f->config->cdev;
572	struct usb_ep *out_ep = audio->out_ep;
573	struct usb_request *req;
574	struct f_uac1_opts *opts;
575	int req_buf_size, req_count, audio_buf_size;
576	int i = 0, err = 0;
577
578	DBG(cdev, "intf %d, alt %d\n", intf, alt);
579
580	opts = container_of(f->fi, struct f_uac1_opts, func_inst);
581	req_buf_size = opts->req_buf_size;
582	req_count = opts->req_count;
583	audio_buf_size = opts->audio_buf_size;
584
585	if (intf == 1) {
586		if (alt == 1) {
587			usb_ep_enable(out_ep);
588			out_ep->driver_data = audio;
589			audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
590			if (IS_ERR(audio->copy_buf))
591				return -ENOMEM;
592
593			/*
594			 * allocate a bunch of read buffers
595			 * and queue them all at once.
596			 */
597			for (i = 0; i < req_count && err == 0; i++) {
598				req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
599				if (req) {
600					req->buf = kzalloc(req_buf_size,
601							GFP_ATOMIC);
602					if (req->buf) {
603						req->length = req_buf_size;
604						req->context = audio;
605						req->complete =
606							f_audio_complete;
607						err = usb_ep_queue(out_ep,
608							req, GFP_ATOMIC);
609						if (err)
610							ERROR(cdev,
611							"%s queue req: %d\n",
612							out_ep->name, err);
613					} else
614						err = -ENOMEM;
615				} else
616					err = -ENOMEM;
617			}
618
619		} else {
620			struct f_audio_buf *copy_buf = audio->copy_buf;
621			if (copy_buf) {
622				list_add_tail(&copy_buf->list,
623						&audio->play_queue);
624				schedule_work(&audio->playback_work);
625			}
626		}
627	}
628
629	return err;
630}
631
632static void f_audio_disable(struct usb_function *f)
633{
634	return;
635}
636
637/*-------------------------------------------------------------------------*/
638
639static void f_audio_build_desc(struct f_audio *audio)
640{
641	struct gaudio *card = &audio->card;
642	u8 *sam_freq;
643	int rate;
644
645	/* Set channel numbers */
646	input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
647	as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
648
649	/* Set sample rates */
650	rate = u_audio_get_playback_rate(card);
651	sam_freq = as_type_i_desc.tSamFreq[0];
652	memcpy(sam_freq, &rate, 3);
653
654	/* Todo: Set Sample bits and other parameters */
655
656	return;
657}
658
659/* audio function driver setup/binding */
660static int
661f_audio_bind(struct usb_configuration *c, struct usb_function *f)
662{
663	struct usb_composite_dev *cdev = c->cdev;
664	struct f_audio		*audio = func_to_audio(f);
665	struct usb_string	*us;
666	int			status;
667	struct usb_ep		*ep = NULL;
668	struct f_uac1_opts	*audio_opts;
669
670	audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst);
671	audio->card.gadget = c->cdev->gadget;
672	audio_opts->card = &audio->card;
673	/* set up ASLA audio devices */
674	if (!audio_opts->bound) {
675		status = gaudio_setup(&audio->card);
676		if (status < 0)
677			return status;
678		audio_opts->bound = true;
679	}
680	us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
681	if (IS_ERR(us))
682		return PTR_ERR(us);
683	ac_interface_desc.iInterface = us[STR_AC_IF].id;
684	input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
685	input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
686	feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
687	output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
688	as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
689	as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
690
691
692	f_audio_build_desc(audio);
693
694	/* allocate instance-specific interface IDs, and patch descriptors */
695	status = usb_interface_id(c, f);
696	if (status < 0)
697		goto fail;
698	ac_interface_desc.bInterfaceNumber = status;
699
700	status = usb_interface_id(c, f);
701	if (status < 0)
702		goto fail;
703	as_interface_alt_0_desc.bInterfaceNumber = status;
704	as_interface_alt_1_desc.bInterfaceNumber = status;
705
706	status = -ENODEV;
707
708	/* allocate instance-specific endpoints */
709	ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
710	if (!ep)
711		goto fail;
712	audio->out_ep = ep;
713	audio->out_ep->desc = &as_out_ep_desc;
714	ep->driver_data = cdev;	/* claim */
715
716	status = -ENOMEM;
717
718	/* copy descriptors, and track endpoint copies */
719	status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL);
720	if (status)
721		goto fail;
722	return 0;
723
724fail:
725	gaudio_cleanup(&audio->card);
726	if (ep)
727		ep->driver_data = NULL;
728	return status;
729}
730
731/*-------------------------------------------------------------------------*/
732
733static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
734{
735	con->data[cmd] = value;
736
737	return 0;
738}
739
740static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
741{
742	return con->data[cmd];
743}
744
745/* Todo: add more control selecotor dynamically */
746static int control_selector_init(struct f_audio *audio)
747{
748	INIT_LIST_HEAD(&audio->cs);
749	list_add(&feature_unit.list, &audio->cs);
750
751	INIT_LIST_HEAD(&feature_unit.control);
752	list_add(&mute_control.list, &feature_unit.control);
753	list_add(&volume_control.list, &feature_unit.control);
754
755	volume_control.data[UAC__CUR] = 0xffc0;
756	volume_control.data[UAC__MIN] = 0xe3a0;
757	volume_control.data[UAC__MAX] = 0xfff0;
758	volume_control.data[UAC__RES] = 0x0030;
759
760	return 0;
761}
762
763static inline struct f_uac1_opts *to_f_uac1_opts(struct config_item *item)
764{
765	return container_of(to_config_group(item), struct f_uac1_opts,
766			    func_inst.group);
767}
768
769CONFIGFS_ATTR_STRUCT(f_uac1_opts);
770CONFIGFS_ATTR_OPS(f_uac1_opts);
771
772static void f_uac1_attr_release(struct config_item *item)
773{
774	struct f_uac1_opts *opts = to_f_uac1_opts(item);
775
776	usb_put_function_instance(&opts->func_inst);
777}
778
779static struct configfs_item_operations f_uac1_item_ops = {
780	.release	= f_uac1_attr_release,
781	.show_attribute	= f_uac1_opts_attr_show,
782	.store_attribute = f_uac1_opts_attr_store,
783};
784
785#define UAC1_INT_ATTRIBUTE(name)					\
786static ssize_t f_uac1_opts_##name##_show(struct f_uac1_opts *opts,	\
787					 char *page)			\
788{									\
789	int result;							\
790									\
791	mutex_lock(&opts->lock);					\
792	result = sprintf(page, "%u\n", opts->name);			\
793	mutex_unlock(&opts->lock);					\
794									\
795	return result;							\
796}									\
797									\
798static ssize_t f_uac1_opts_##name##_store(struct f_uac1_opts *opts,	\
799					  const char *page, size_t len)	\
800{									\
801	int ret;							\
802	u32 num;							\
803									\
804	mutex_lock(&opts->lock);					\
805	if (opts->refcnt) {						\
806		ret = -EBUSY;						\
807		goto end;						\
808	}								\
809									\
810	ret = kstrtou32(page, 0, &num);					\
811	if (ret)							\
812		goto end;						\
813									\
814	opts->name = num;						\
815	ret = len;							\
816									\
817end:									\
818	mutex_unlock(&opts->lock);					\
819	return ret;							\
820}									\
821									\
822static struct f_uac1_opts_attribute f_uac1_opts_##name =		\
823	__CONFIGFS_ATTR(name, S_IRUGO | S_IWUSR,			\
824			f_uac1_opts_##name##_show,			\
825			f_uac1_opts_##name##_store)
826
827UAC1_INT_ATTRIBUTE(req_buf_size);
828UAC1_INT_ATTRIBUTE(req_count);
829UAC1_INT_ATTRIBUTE(audio_buf_size);
830
831#define UAC1_STR_ATTRIBUTE(name)					\
832static ssize_t f_uac1_opts_##name##_show(struct f_uac1_opts *opts,	\
833					 char *page)			\
834{									\
835	int result;							\
836									\
837	mutex_lock(&opts->lock);					\
838	result = sprintf(page, "%s\n", opts->name);			\
839	mutex_unlock(&opts->lock);					\
840									\
841	return result;							\
842}									\
843									\
844static ssize_t f_uac1_opts_##name##_store(struct f_uac1_opts *opts,	\
845					  const char *page, size_t len)	\
846{									\
847	int ret = -EBUSY;						\
848	char *tmp;							\
849									\
850	mutex_lock(&opts->lock);					\
851	if (opts->refcnt)						\
852		goto end;						\
853									\
854	tmp = kstrndup(page, len, GFP_KERNEL);				\
855	if (tmp) {							\
856		ret = -ENOMEM;						\
857		goto end;						\
858	}								\
859	if (opts->name##_alloc)						\
860		kfree(opts->name);					\
861	opts->name##_alloc = true;					\
862	opts->name = tmp;						\
863	ret = len;							\
864									\
865end:									\
866	mutex_unlock(&opts->lock);					\
867	return ret;							\
868}									\
869									\
870static struct f_uac1_opts_attribute f_uac1_opts_##name =		\
871	__CONFIGFS_ATTR(name, S_IRUGO | S_IWUSR,			\
872			f_uac1_opts_##name##_show,			\
873			f_uac1_opts_##name##_store)
874
875UAC1_STR_ATTRIBUTE(fn_play);
876UAC1_STR_ATTRIBUTE(fn_cap);
877UAC1_STR_ATTRIBUTE(fn_cntl);
878
879static struct configfs_attribute *f_uac1_attrs[] = {
880	&f_uac1_opts_req_buf_size.attr,
881	&f_uac1_opts_req_count.attr,
882	&f_uac1_opts_audio_buf_size.attr,
883	&f_uac1_opts_fn_play.attr,
884	&f_uac1_opts_fn_cap.attr,
885	&f_uac1_opts_fn_cntl.attr,
886	NULL,
887};
888
889static struct config_item_type f_uac1_func_type = {
890	.ct_item_ops	= &f_uac1_item_ops,
891	.ct_attrs	= f_uac1_attrs,
892	.ct_owner	= THIS_MODULE,
893};
894
895static void f_audio_free_inst(struct usb_function_instance *f)
896{
897	struct f_uac1_opts *opts;
898
899	opts = container_of(f, struct f_uac1_opts, func_inst);
900	gaudio_cleanup(opts->card);
901	if (opts->fn_play_alloc)
902		kfree(opts->fn_play);
903	if (opts->fn_cap_alloc)
904		kfree(opts->fn_cap);
905	if (opts->fn_cntl_alloc)
906		kfree(opts->fn_cntl);
907	kfree(opts);
908}
909
910static struct usb_function_instance *f_audio_alloc_inst(void)
911{
912	struct f_uac1_opts *opts;
913
914	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
915	if (!opts)
916		return ERR_PTR(-ENOMEM);
917
918	mutex_init(&opts->lock);
919	opts->func_inst.free_func_inst = f_audio_free_inst;
920
921	config_group_init_type_name(&opts->func_inst.group, "",
922				    &f_uac1_func_type);
923
924	opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
925	opts->req_count = UAC1_REQ_COUNT;
926	opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
927	opts->fn_play = FILE_PCM_PLAYBACK;
928	opts->fn_cap = FILE_PCM_CAPTURE;
929	opts->fn_cntl = FILE_CONTROL;
930	return &opts->func_inst;
931}
932
933static void f_audio_free(struct usb_function *f)
934{
935	struct f_audio *audio = func_to_audio(f);
936	struct f_uac1_opts *opts;
937
938	opts = container_of(f->fi, struct f_uac1_opts, func_inst);
939	kfree(audio);
940	mutex_lock(&opts->lock);
941	--opts->refcnt;
942	mutex_unlock(&opts->lock);
943}
944
945static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
946{
947	usb_free_all_descriptors(f);
948}
949
950static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
951{
952	struct f_audio *audio;
953	struct f_uac1_opts *opts;
954
955	/* allocate and initialize one new instance */
956	audio = kzalloc(sizeof(*audio), GFP_KERNEL);
957	if (!audio)
958		return ERR_PTR(-ENOMEM);
959
960	audio->card.func.name = "g_audio";
961
962	opts = container_of(fi, struct f_uac1_opts, func_inst);
963	mutex_lock(&opts->lock);
964	++opts->refcnt;
965	mutex_unlock(&opts->lock);
966	INIT_LIST_HEAD(&audio->play_queue);
967	spin_lock_init(&audio->lock);
968
969	audio->card.func.bind = f_audio_bind;
970	audio->card.func.unbind = f_audio_unbind;
971	audio->card.func.set_alt = f_audio_set_alt;
972	audio->card.func.setup = f_audio_setup;
973	audio->card.func.disable = f_audio_disable;
974	audio->card.func.free_func = f_audio_free;
975
976	control_selector_init(audio);
977
978	INIT_WORK(&audio->playback_work, f_audio_playback_work);
979
980	return &audio->card.func;
981}
982
983DECLARE_USB_FUNCTION_INIT(uac1, f_audio_alloc_inst, f_audio_alloc);
984MODULE_LICENSE("GPL");
985MODULE_AUTHOR("Bryan Wu");
986