1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * f_uac1.c -- USB Audio Class 1.0 Function (using u_audio API)
4  *
5  * Copyright (C) 2016 Ruslan Bilovol <ruslan.bilovol@gmail.com>
6  *
7  * This driver doesn't expect any real Audio codec to be present
8  * on the device - the audio streams are simply sinked to and
9  * sourced from a virtual ALSA sound card created.
10  *
11  * This file is based on f_uac1.c which is
12  *   Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
13  *   Copyright (C) 2008 Analog Devices, Inc
14  */
15 
16 #include <linux/usb/audio.h>
17 #include <linux/module.h>
18 
19 #include "u_audio.h"
20 #include "u_uac1.h"
21 
22 /* UAC1 spec: 3.7.2.3 Audio Channel Cluster Format */
23 #define UAC1_CHANNEL_MASK 0x0FFF
24 
25 #define USB_OUT_FU_ID	(out_feature_unit_desc->bUnitID)
26 #define USB_IN_FU_ID	(in_feature_unit_desc->bUnitID)
27 
28 #define EPIN_EN(_opts) ((_opts)->p_chmask != 0)
29 #define EPOUT_EN(_opts) ((_opts)->c_chmask != 0)
30 #define FUIN_EN(_opts) ((_opts)->p_mute_present \
31 			|| (_opts)->p_volume_present)
32 #define FUOUT_EN(_opts) ((_opts)->c_mute_present \
33 			|| (_opts)->c_volume_present)
34 
35 struct f_uac1 {
36 	struct g_audio g_audio;
37 	u8 ac_intf, as_in_intf, as_out_intf;
38 	u8 ac_alt, as_in_alt, as_out_alt;	/* needed for get_alt() */
39 
40 	struct usb_ctrlrequest setup_cr;	/* will be used in data stage */
41 
42 	/* Interrupt IN endpoint of AC interface */
43 	struct usb_ep	*int_ep;
44 	atomic_t	int_count;
45 };
46 
47 static inline struct f_uac1 *func_to_uac1(struct usb_function *f)
48 {
49 	return container_of(f, struct f_uac1, g_audio.func);
50 }
51 
52 static inline struct f_uac1_opts *g_audio_to_uac1_opts(struct g_audio *audio)
53 {
54 	return container_of(audio->func.fi, struct f_uac1_opts, func_inst);
55 }
56 
57 /*
58  * DESCRIPTORS ... most are static, but strings and full
59  * configuration descriptors are built on demand.
60  */
61 
62 /*
63  * We have three interfaces - one AudioControl and two AudioStreaming
64  *
65  * The driver implements a simple UAC_1 topology.
66  * USB-OUT -> IT_1 -> OT_2 -> ALSA_Capture
67  * ALSA_Playback -> IT_3 -> OT_4 -> USB-IN
68  */
69 
70 /* B.3.1  Standard AC Interface Descriptor */
71 static struct usb_interface_descriptor ac_interface_desc = {
72 	.bLength =		USB_DT_INTERFACE_SIZE,
73 	.bDescriptorType =	USB_DT_INTERFACE,
74 	/* .bNumEndpoints =	DYNAMIC */
75 	.bInterfaceClass =	USB_CLASS_AUDIO,
76 	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOCONTROL,
77 };
78 
79 /* B.3.2  Class-Specific AC Interface Descriptor */
80 static struct uac1_ac_header_descriptor *ac_header_desc;
81 
82 static struct uac_input_terminal_descriptor usb_out_it_desc = {
83 	.bLength =		UAC_DT_INPUT_TERMINAL_SIZE,
84 	.bDescriptorType =	USB_DT_CS_INTERFACE,
85 	.bDescriptorSubtype =	UAC_INPUT_TERMINAL,
86 	/* .bTerminalID =	DYNAMIC */
87 	.wTerminalType =	cpu_to_le16(UAC_TERMINAL_STREAMING),
88 	.bAssocTerminal =	0,
89 	.wChannelConfig =	cpu_to_le16(0x3),
90 };
91 
92 static struct uac1_output_terminal_descriptor io_out_ot_desc = {
93 	.bLength		= UAC_DT_OUTPUT_TERMINAL_SIZE,
94 	.bDescriptorType	= USB_DT_CS_INTERFACE,
95 	.bDescriptorSubtype	= UAC_OUTPUT_TERMINAL,
96 	/* .bTerminalID =	DYNAMIC */
97 	.wTerminalType		= cpu_to_le16(UAC_OUTPUT_TERMINAL_SPEAKER),
98 	.bAssocTerminal		= 0,
99 	/* .bSourceID =		DYNAMIC */
100 };
101 
102 static struct uac_input_terminal_descriptor io_in_it_desc = {
103 	.bLength		= UAC_DT_INPUT_TERMINAL_SIZE,
104 	.bDescriptorType	= USB_DT_CS_INTERFACE,
105 	.bDescriptorSubtype	= UAC_INPUT_TERMINAL,
106 	/* .bTerminalID		= DYNAMIC */
107 	.wTerminalType		= cpu_to_le16(UAC_INPUT_TERMINAL_MICROPHONE),
108 	.bAssocTerminal		= 0,
109 	.wChannelConfig		= cpu_to_le16(0x3),
110 };
111 
112 static struct uac1_output_terminal_descriptor usb_in_ot_desc = {
113 	.bLength =		UAC_DT_OUTPUT_TERMINAL_SIZE,
114 	.bDescriptorType =	USB_DT_CS_INTERFACE,
115 	.bDescriptorSubtype =	UAC_OUTPUT_TERMINAL,
116 	/* .bTerminalID =	DYNAMIC */
117 	.wTerminalType =	cpu_to_le16(UAC_TERMINAL_STREAMING),
118 	.bAssocTerminal =	0,
119 	/* .bSourceID =		DYNAMIC */
120 };
121 
122 static struct uac_feature_unit_descriptor *in_feature_unit_desc;
123 static struct uac_feature_unit_descriptor *out_feature_unit_desc;
124 
125 /* AC IN Interrupt Endpoint */
126 static struct usb_endpoint_descriptor ac_int_ep_desc = {
127 	.bLength = USB_DT_ENDPOINT_SIZE,
128 	.bDescriptorType = USB_DT_ENDPOINT,
129 	.bEndpointAddress = USB_DIR_IN,
130 	.bmAttributes = USB_ENDPOINT_XFER_INT,
131 	.wMaxPacketSize = cpu_to_le16(2),
132 	.bInterval = 4,
133 };
134 
135 /* B.4.1  Standard AS Interface Descriptor */
136 static struct usb_interface_descriptor as_out_interface_alt_0_desc = {
137 	.bLength =		USB_DT_INTERFACE_SIZE,
138 	.bDescriptorType =	USB_DT_INTERFACE,
139 	.bAlternateSetting =	0,
140 	.bNumEndpoints =	0,
141 	.bInterfaceClass =	USB_CLASS_AUDIO,
142 	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
143 };
144 
145 static struct usb_interface_descriptor as_out_interface_alt_1_desc = {
146 	.bLength =		USB_DT_INTERFACE_SIZE,
147 	.bDescriptorType =	USB_DT_INTERFACE,
148 	.bAlternateSetting =	1,
149 	.bNumEndpoints =	1,
150 	.bInterfaceClass =	USB_CLASS_AUDIO,
151 	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
152 };
153 
154 static struct usb_interface_descriptor as_in_interface_alt_0_desc = {
155 	.bLength =		USB_DT_INTERFACE_SIZE,
156 	.bDescriptorType =	USB_DT_INTERFACE,
157 	.bAlternateSetting =	0,
158 	.bNumEndpoints =	0,
159 	.bInterfaceClass =	USB_CLASS_AUDIO,
160 	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
161 };
162 
163 static struct usb_interface_descriptor as_in_interface_alt_1_desc = {
164 	.bLength =		USB_DT_INTERFACE_SIZE,
165 	.bDescriptorType =	USB_DT_INTERFACE,
166 	.bAlternateSetting =	1,
167 	.bNumEndpoints =	1,
168 	.bInterfaceClass =	USB_CLASS_AUDIO,
169 	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOSTREAMING,
170 };
171 
172 /* B.4.2  Class-Specific AS Interface Descriptor */
173 static struct uac1_as_header_descriptor as_out_header_desc = {
174 	.bLength =		UAC_DT_AS_HEADER_SIZE,
175 	.bDescriptorType =	USB_DT_CS_INTERFACE,
176 	.bDescriptorSubtype =	UAC_AS_GENERAL,
177 	/* .bTerminalLink =	DYNAMIC */
178 	.bDelay =		1,
179 	.wFormatTag =		cpu_to_le16(UAC_FORMAT_TYPE_I_PCM),
180 };
181 
182 static struct uac1_as_header_descriptor as_in_header_desc = {
183 	.bLength =		UAC_DT_AS_HEADER_SIZE,
184 	.bDescriptorType =	USB_DT_CS_INTERFACE,
185 	.bDescriptorSubtype =	UAC_AS_GENERAL,
186 	/* .bTerminalLink =	DYNAMIC */
187 	.bDelay =		1,
188 	.wFormatTag =		cpu_to_le16(UAC_FORMAT_TYPE_I_PCM),
189 };
190 
191 DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
192 
193 static struct uac_format_type_i_discrete_descriptor_1 as_out_type_i_desc = {
194 	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
195 	.bDescriptorType =	USB_DT_CS_INTERFACE,
196 	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
197 	.bFormatType =		UAC_FORMAT_TYPE_I,
198 	.bSubframeSize =	2,
199 	.bBitResolution =	16,
200 	.bSamFreqType =		1,
201 };
202 
203 /* Standard ISO OUT Endpoint Descriptor */
204 static struct usb_endpoint_descriptor as_out_ep_desc  = {
205 	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
206 	.bDescriptorType =	USB_DT_ENDPOINT,
207 	.bEndpointAddress =	USB_DIR_OUT,
208 	.bmAttributes =		USB_ENDPOINT_SYNC_ADAPTIVE
209 				| USB_ENDPOINT_XFER_ISOC,
210 	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
211 	.bInterval =		4,
212 };
213 
214 /* Class-specific AS ISO OUT Endpoint Descriptor */
215 static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
216 	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
217 	.bDescriptorType =	USB_DT_CS_ENDPOINT,
218 	.bDescriptorSubtype =	UAC_EP_GENERAL,
219 	.bmAttributes =		1,
220 	.bLockDelayUnits =	1,
221 	.wLockDelay =		cpu_to_le16(1),
222 };
223 
224 static struct uac_format_type_i_discrete_descriptor_1 as_in_type_i_desc = {
225 	.bLength =		UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
226 	.bDescriptorType =	USB_DT_CS_INTERFACE,
227 	.bDescriptorSubtype =	UAC_FORMAT_TYPE,
228 	.bFormatType =		UAC_FORMAT_TYPE_I,
229 	.bSubframeSize =	2,
230 	.bBitResolution =	16,
231 	.bSamFreqType =		1,
232 };
233 
234 /* Standard ISO OUT Endpoint Descriptor */
235 static struct usb_endpoint_descriptor as_in_ep_desc  = {
236 	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
237 	.bDescriptorType =	USB_DT_ENDPOINT,
238 	.bEndpointAddress =	USB_DIR_IN,
239 	.bmAttributes =		USB_ENDPOINT_SYNC_ASYNC
240 				| USB_ENDPOINT_XFER_ISOC,
241 	.wMaxPacketSize	=	cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
242 	.bInterval =		4,
243 };
244 
245 /* Class-specific AS ISO OUT Endpoint Descriptor */
246 static struct uac_iso_endpoint_descriptor as_iso_in_desc = {
247 	.bLength =		UAC_ISO_ENDPOINT_DESC_SIZE,
248 	.bDescriptorType =	USB_DT_CS_ENDPOINT,
249 	.bDescriptorSubtype =	UAC_EP_GENERAL,
250 	.bmAttributes =		1,
251 	.bLockDelayUnits =	0,
252 	.wLockDelay =		0,
253 };
254 
255 static struct usb_descriptor_header *f_audio_desc[] = {
256 	(struct usb_descriptor_header *)&ac_interface_desc,
257 	(struct usb_descriptor_header *)&ac_header_desc,
258 
259 	(struct usb_descriptor_header *)&usb_out_it_desc,
260 	(struct usb_descriptor_header *)&io_out_ot_desc,
261 	(struct usb_descriptor_header *)&out_feature_unit_desc,
262 
263 	(struct usb_descriptor_header *)&io_in_it_desc,
264 	(struct usb_descriptor_header *)&usb_in_ot_desc,
265 	(struct usb_descriptor_header *)&in_feature_unit_desc,
266 
267 	(struct usb_descriptor_header *)&ac_int_ep_desc,
268 
269 	(struct usb_descriptor_header *)&as_out_interface_alt_0_desc,
270 	(struct usb_descriptor_header *)&as_out_interface_alt_1_desc,
271 	(struct usb_descriptor_header *)&as_out_header_desc,
272 
273 	(struct usb_descriptor_header *)&as_out_type_i_desc,
274 
275 	(struct usb_descriptor_header *)&as_out_ep_desc,
276 	(struct usb_descriptor_header *)&as_iso_out_desc,
277 
278 	(struct usb_descriptor_header *)&as_in_interface_alt_0_desc,
279 	(struct usb_descriptor_header *)&as_in_interface_alt_1_desc,
280 	(struct usb_descriptor_header *)&as_in_header_desc,
281 
282 	(struct usb_descriptor_header *)&as_in_type_i_desc,
283 
284 	(struct usb_descriptor_header *)&as_in_ep_desc,
285 	(struct usb_descriptor_header *)&as_iso_in_desc,
286 	NULL,
287 };
288 
289 enum {
290 	STR_AC_IF,
291 	STR_USB_OUT_IT,
292 	STR_USB_OUT_IT_CH_NAMES,
293 	STR_IO_OUT_OT,
294 	STR_IO_IN_IT,
295 	STR_IO_IN_IT_CH_NAMES,
296 	STR_USB_IN_OT,
297 	STR_FU_IN,
298 	STR_FU_OUT,
299 	STR_AS_OUT_IF_ALT0,
300 	STR_AS_OUT_IF_ALT1,
301 	STR_AS_IN_IF_ALT0,
302 	STR_AS_IN_IF_ALT1,
303 };
304 
305 static struct usb_string strings_uac1[] = {
306 	[STR_AC_IF].s = "AC Interface",
307 	[STR_USB_OUT_IT].s = "Playback Input terminal",
308 	[STR_USB_OUT_IT_CH_NAMES].s = "Playback Channels",
309 	[STR_IO_OUT_OT].s = "Playback Output terminal",
310 	[STR_IO_IN_IT].s = "Capture Input terminal",
311 	[STR_IO_IN_IT_CH_NAMES].s = "Capture Channels",
312 	[STR_USB_IN_OT].s = "Capture Output terminal",
313 	[STR_FU_IN].s = "Capture Volume",
314 	[STR_FU_OUT].s = "Playback Volume",
315 	[STR_AS_OUT_IF_ALT0].s = "Playback Inactive",
316 	[STR_AS_OUT_IF_ALT1].s = "Playback Active",
317 	[STR_AS_IN_IF_ALT0].s = "Capture Inactive",
318 	[STR_AS_IN_IF_ALT1].s = "Capture Active",
319 	{ },
320 };
321 
322 static struct usb_gadget_strings str_uac1 = {
323 	.language = 0x0409,	/* en-us */
324 	.strings = strings_uac1,
325 };
326 
327 static struct usb_gadget_strings *uac1_strings[] = {
328 	&str_uac1,
329 	NULL,
330 };
331 
332 /*
333  * This function is an ALSA sound card following USB Audio Class Spec 1.0.
334  */
335 
336 static void audio_notify_complete(struct usb_ep *_ep, struct usb_request *req)
337 {
338 	struct g_audio *audio = req->context;
339 	struct f_uac1 *uac1 = func_to_uac1(&audio->func);
340 
341 	atomic_dec(&uac1->int_count);
342 	kfree(req->buf);
343 	usb_ep_free_request(_ep, req);
344 }
345 
346 static int audio_notify(struct g_audio *audio, int unit_id, int cs)
347 {
348 	struct f_uac1 *uac1 = func_to_uac1(&audio->func);
349 	struct usb_request *req;
350 	struct uac1_status_word *msg;
351 	int ret;
352 
353 	if (!uac1->int_ep->enabled)
354 		return 0;
355 
356 	if (atomic_inc_return(&uac1->int_count) > UAC1_DEF_INT_REQ_NUM) {
357 		atomic_dec(&uac1->int_count);
358 		return 0;
359 	}
360 
361 	req = usb_ep_alloc_request(uac1->int_ep, GFP_ATOMIC);
362 	if (req == NULL) {
363 		ret = -ENOMEM;
364 		goto err_dec_int_count;
365 	}
366 
367 	msg = kmalloc(sizeof(*msg), GFP_ATOMIC);
368 	if (msg == NULL) {
369 		ret = -ENOMEM;
370 		goto err_free_request;
371 	}
372 
373 	msg->bStatusType = UAC1_STATUS_TYPE_IRQ_PENDING
374 				| UAC1_STATUS_TYPE_ORIG_AUDIO_CONTROL_IF;
375 	msg->bOriginator = unit_id;
376 
377 	req->length = sizeof(*msg);
378 	req->buf = msg;
379 	req->context = audio;
380 	req->complete = audio_notify_complete;
381 
382 	ret = usb_ep_queue(uac1->int_ep, req, GFP_ATOMIC);
383 
384 	if (ret)
385 		goto err_free_msg;
386 
387 	return 0;
388 
389 err_free_msg:
390 	kfree(msg);
391 err_free_request:
392 	usb_ep_free_request(uac1->int_ep, req);
393 err_dec_int_count:
394 	atomic_dec(&uac1->int_count);
395 
396 	return ret;
397 }
398 
399 static int
400 in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
401 {
402 	struct usb_request *req = fn->config->cdev->req;
403 	struct g_audio *audio = func_to_g_audio(fn);
404 	struct f_uac1_opts *opts = g_audio_to_uac1_opts(audio);
405 	u16 w_length = le16_to_cpu(cr->wLength);
406 	u16 w_index = le16_to_cpu(cr->wIndex);
407 	u16 w_value = le16_to_cpu(cr->wValue);
408 	u8 entity_id = (w_index >> 8) & 0xff;
409 	u8 control_selector = w_value >> 8;
410 	int value = -EOPNOTSUPP;
411 
412 	if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
413 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
414 		unsigned int is_playback = 0;
415 
416 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
417 			is_playback = 1;
418 
419 		if (control_selector == UAC_FU_MUTE) {
420 			unsigned int mute;
421 
422 			u_audio_get_mute(audio, is_playback, &mute);
423 
424 			*(u8 *)req->buf = mute;
425 			value = min_t(unsigned int, w_length, 1);
426 		} else if (control_selector == UAC_FU_VOLUME) {
427 			__le16 c;
428 			s16 volume;
429 
430 			u_audio_get_volume(audio, is_playback, &volume);
431 
432 			c = cpu_to_le16(volume);
433 
434 			value = min_t(unsigned int, w_length, sizeof(c));
435 			memcpy(req->buf, &c, value);
436 		} else {
437 			dev_err(&audio->gadget->dev,
438 				"%s:%d control_selector=%d TODO!\n",
439 				__func__, __LINE__, control_selector);
440 		}
441 	} else {
442 		dev_err(&audio->gadget->dev,
443 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
444 			__func__, __LINE__, entity_id, control_selector);
445 	}
446 
447 	return value;
448 }
449 
450 static int
451 in_rq_min(struct usb_function *fn, const struct usb_ctrlrequest *cr)
452 {
453 	struct usb_request *req = fn->config->cdev->req;
454 	struct g_audio *audio = func_to_g_audio(fn);
455 	struct f_uac1_opts *opts = g_audio_to_uac1_opts(audio);
456 	u16 w_length = le16_to_cpu(cr->wLength);
457 	u16 w_index = le16_to_cpu(cr->wIndex);
458 	u16 w_value = le16_to_cpu(cr->wValue);
459 	u8 entity_id = (w_index >> 8) & 0xff;
460 	u8 control_selector = w_value >> 8;
461 	int value = -EOPNOTSUPP;
462 
463 	if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
464 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
465 		unsigned int is_playback = 0;
466 
467 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
468 			is_playback = 1;
469 
470 		if (control_selector == UAC_FU_VOLUME) {
471 			__le16 r;
472 			s16 min_db;
473 
474 			if (is_playback)
475 				min_db = opts->p_volume_min;
476 			else
477 				min_db = opts->c_volume_min;
478 
479 			r = cpu_to_le16(min_db);
480 
481 			value = min_t(unsigned int, w_length, sizeof(r));
482 			memcpy(req->buf, &r, value);
483 		} else {
484 			dev_err(&audio->gadget->dev,
485 				"%s:%d control_selector=%d TODO!\n",
486 				__func__, __LINE__, control_selector);
487 		}
488 	} else {
489 		dev_err(&audio->gadget->dev,
490 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
491 			__func__, __LINE__, entity_id, control_selector);
492 	}
493 
494 	return value;
495 }
496 
497 static int
498 in_rq_max(struct usb_function *fn, const struct usb_ctrlrequest *cr)
499 {
500 	struct usb_request *req = fn->config->cdev->req;
501 	struct g_audio *audio = func_to_g_audio(fn);
502 	struct f_uac1_opts *opts = g_audio_to_uac1_opts(audio);
503 	u16 w_length = le16_to_cpu(cr->wLength);
504 	u16 w_index = le16_to_cpu(cr->wIndex);
505 	u16 w_value = le16_to_cpu(cr->wValue);
506 	u8 entity_id = (w_index >> 8) & 0xff;
507 	u8 control_selector = w_value >> 8;
508 	int value = -EOPNOTSUPP;
509 
510 	if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
511 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
512 		unsigned int is_playback = 0;
513 
514 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
515 			is_playback = 1;
516 
517 		if (control_selector == UAC_FU_VOLUME) {
518 			__le16 r;
519 			s16 max_db;
520 
521 			if (is_playback)
522 				max_db = opts->p_volume_max;
523 			else
524 				max_db = opts->c_volume_max;
525 
526 			r = cpu_to_le16(max_db);
527 
528 			value = min_t(unsigned int, w_length, sizeof(r));
529 			memcpy(req->buf, &r, value);
530 		} else {
531 			dev_err(&audio->gadget->dev,
532 				"%s:%d control_selector=%d TODO!\n",
533 				__func__, __LINE__, control_selector);
534 		}
535 	} else {
536 		dev_err(&audio->gadget->dev,
537 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
538 			__func__, __LINE__, entity_id, control_selector);
539 	}
540 
541 	return value;
542 }
543 
544 static int
545 in_rq_res(struct usb_function *fn, const struct usb_ctrlrequest *cr)
546 {
547 	struct usb_request *req = fn->config->cdev->req;
548 	struct g_audio *audio = func_to_g_audio(fn);
549 	struct f_uac1_opts *opts = g_audio_to_uac1_opts(audio);
550 	u16 w_length = le16_to_cpu(cr->wLength);
551 	u16 w_index = le16_to_cpu(cr->wIndex);
552 	u16 w_value = le16_to_cpu(cr->wValue);
553 	u8 entity_id = (w_index >> 8) & 0xff;
554 	u8 control_selector = w_value >> 8;
555 	int value = -EOPNOTSUPP;
556 
557 	if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
558 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
559 		unsigned int is_playback = 0;
560 
561 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
562 			is_playback = 1;
563 
564 		if (control_selector == UAC_FU_VOLUME) {
565 			__le16 r;
566 			s16 res_db;
567 
568 			if (is_playback)
569 				res_db = opts->p_volume_res;
570 			else
571 				res_db = opts->c_volume_res;
572 
573 			r = cpu_to_le16(res_db);
574 
575 			value = min_t(unsigned int, w_length, sizeof(r));
576 			memcpy(req->buf, &r, value);
577 		} else {
578 			dev_err(&audio->gadget->dev,
579 				"%s:%d control_selector=%d TODO!\n",
580 				__func__, __LINE__, control_selector);
581 		}
582 	} else {
583 		dev_err(&audio->gadget->dev,
584 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
585 			__func__, __LINE__, entity_id, control_selector);
586 	}
587 
588 	return value;
589 }
590 
591 static void
592 out_rq_cur_complete(struct usb_ep *ep, struct usb_request *req)
593 {
594 	struct g_audio *audio = req->context;
595 	struct usb_composite_dev *cdev = audio->func.config->cdev;
596 	struct f_uac1_opts *opts = g_audio_to_uac1_opts(audio);
597 	struct f_uac1 *uac1 = func_to_uac1(&audio->func);
598 	struct usb_ctrlrequest *cr = &uac1->setup_cr;
599 	u16 w_index = le16_to_cpu(cr->wIndex);
600 	u16 w_value = le16_to_cpu(cr->wValue);
601 	u8 entity_id = (w_index >> 8) & 0xff;
602 	u8 control_selector = w_value >> 8;
603 
604 	if (req->status != 0) {
605 		dev_dbg(&cdev->gadget->dev, "completion err %d\n", req->status);
606 		return;
607 	}
608 
609 	if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
610 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
611 		unsigned int is_playback = 0;
612 
613 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
614 			is_playback = 1;
615 
616 		if (control_selector == UAC_FU_MUTE) {
617 			u8 mute = *(u8 *)req->buf;
618 
619 			u_audio_set_mute(audio, is_playback, mute);
620 
621 			return;
622 		} else if (control_selector == UAC_FU_VOLUME) {
623 			__le16 *c = req->buf;
624 			s16 volume;
625 
626 			volume = le16_to_cpu(*c);
627 			u_audio_set_volume(audio, is_playback, volume);
628 
629 			return;
630 		} else {
631 			dev_err(&audio->gadget->dev,
632 				"%s:%d control_selector=%d TODO!\n",
633 				__func__, __LINE__, control_selector);
634 			usb_ep_set_halt(ep);
635 		}
636 	} else {
637 		dev_err(&audio->gadget->dev,
638 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
639 			__func__, __LINE__, entity_id, control_selector);
640 		usb_ep_set_halt(ep);
641 
642 	}
643 }
644 
645 static int
646 out_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
647 {
648 	struct usb_request *req = fn->config->cdev->req;
649 	struct g_audio *audio = func_to_g_audio(fn);
650 	struct f_uac1_opts *opts = g_audio_to_uac1_opts(audio);
651 	struct f_uac1 *uac1 = func_to_uac1(&audio->func);
652 	u16 w_length = le16_to_cpu(cr->wLength);
653 	u16 w_index = le16_to_cpu(cr->wIndex);
654 	u16 w_value = le16_to_cpu(cr->wValue);
655 	u8 entity_id = (w_index >> 8) & 0xff;
656 	u8 control_selector = w_value >> 8;
657 
658 	if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
659 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
660 		memcpy(&uac1->setup_cr, cr, sizeof(*cr));
661 		req->context = audio;
662 		req->complete = out_rq_cur_complete;
663 
664 		return w_length;
665 	} else {
666 		dev_err(&audio->gadget->dev,
667 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
668 			__func__, __LINE__, entity_id, control_selector);
669 	}
670 	return -EOPNOTSUPP;
671 }
672 
673 static int ac_rq_in(struct usb_function *f,
674 		const struct usb_ctrlrequest *ctrl)
675 {
676 	struct usb_composite_dev *cdev = f->config->cdev;
677 	int value = -EOPNOTSUPP;
678 	u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
679 	u16 len = le16_to_cpu(ctrl->wLength);
680 	u16 w_value = le16_to_cpu(ctrl->wValue);
681 
682 	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
683 			ctrl->bRequest, w_value, len, ep);
684 
685 	switch (ctrl->bRequest) {
686 	case UAC_GET_CUR:
687 		return in_rq_cur(f, ctrl);
688 	case UAC_GET_MIN:
689 		return in_rq_min(f, ctrl);
690 	case UAC_GET_MAX:
691 		return in_rq_max(f, ctrl);
692 	case UAC_GET_RES:
693 		return in_rq_res(f, ctrl);
694 	case UAC_GET_MEM:
695 		break;
696 	case UAC_GET_STAT:
697 		value = len;
698 		break;
699 	default:
700 		break;
701 	}
702 
703 	return value;
704 }
705 
706 static int audio_set_endpoint_req(struct usb_function *f,
707 		const struct usb_ctrlrequest *ctrl)
708 {
709 	struct usb_composite_dev *cdev = f->config->cdev;
710 	int			value = -EOPNOTSUPP;
711 	u16			ep = le16_to_cpu(ctrl->wIndex);
712 	u16			len = le16_to_cpu(ctrl->wLength);
713 	u16			w_value = le16_to_cpu(ctrl->wValue);
714 
715 	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
716 			ctrl->bRequest, w_value, len, ep);
717 
718 	switch (ctrl->bRequest) {
719 	case UAC_SET_CUR:
720 		value = len;
721 		break;
722 
723 	case UAC_SET_MIN:
724 		break;
725 
726 	case UAC_SET_MAX:
727 		break;
728 
729 	case UAC_SET_RES:
730 		break;
731 
732 	case UAC_SET_MEM:
733 		break;
734 
735 	default:
736 		break;
737 	}
738 
739 	return value;
740 }
741 
742 static int audio_get_endpoint_req(struct usb_function *f,
743 		const struct usb_ctrlrequest *ctrl)
744 {
745 	struct usb_composite_dev *cdev = f->config->cdev;
746 	int value = -EOPNOTSUPP;
747 	u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
748 	u16 len = le16_to_cpu(ctrl->wLength);
749 	u16 w_value = le16_to_cpu(ctrl->wValue);
750 
751 	DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
752 			ctrl->bRequest, w_value, len, ep);
753 
754 	switch (ctrl->bRequest) {
755 	case UAC_GET_CUR:
756 	case UAC_GET_MIN:
757 	case UAC_GET_MAX:
758 	case UAC_GET_RES:
759 		value = len;
760 		break;
761 	case UAC_GET_MEM:
762 		break;
763 	default:
764 		break;
765 	}
766 
767 	return value;
768 }
769 
770 static int
771 f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
772 {
773 	struct usb_composite_dev *cdev = f->config->cdev;
774 	struct usb_request	*req = cdev->req;
775 	int			value = -EOPNOTSUPP;
776 	u16			w_index = le16_to_cpu(ctrl->wIndex);
777 	u16			w_value = le16_to_cpu(ctrl->wValue);
778 	u16			w_length = le16_to_cpu(ctrl->wLength);
779 
780 	/* composite driver infrastructure handles everything; interface
781 	 * activation uses set_alt().
782 	 */
783 	switch (ctrl->bRequestType) {
784 	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
785 		value = audio_set_endpoint_req(f, ctrl);
786 		break;
787 
788 	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
789 		value = audio_get_endpoint_req(f, ctrl);
790 		break;
791 	case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
792 		if (ctrl->bRequest == UAC_SET_CUR)
793 			value = out_rq_cur(f, ctrl);
794 		break;
795 	case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
796 		value = ac_rq_in(f, ctrl);
797 		break;
798 	default:
799 		ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
800 			ctrl->bRequestType, ctrl->bRequest,
801 			w_value, w_index, w_length);
802 	}
803 
804 	/* respond with data transfer or status phase? */
805 	if (value >= 0) {
806 		DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
807 			ctrl->bRequestType, ctrl->bRequest,
808 			w_value, w_index, w_length);
809 		req->zero = 0;
810 		req->length = value;
811 		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
812 		if (value < 0)
813 			ERROR(cdev, "audio response on err %d\n", value);
814 	}
815 
816 	/* device either stalls (value < 0) or reports success */
817 	return value;
818 }
819 
820 static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
821 {
822 	struct usb_composite_dev *cdev = f->config->cdev;
823 	struct usb_gadget *gadget = cdev->gadget;
824 	struct device *dev = &gadget->dev;
825 	struct g_audio *audio = func_to_g_audio(f);
826 	struct f_uac1 *uac1 = func_to_uac1(f);
827 	int ret = 0;
828 
829 	/* No i/f has more than 2 alt settings */
830 	if (alt > 1) {
831 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
832 		return -EINVAL;
833 	}
834 
835 	if (intf == uac1->ac_intf) {
836 		/* Control I/f has only 1 AltSetting - 0 */
837 		if (alt) {
838 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
839 			return -EINVAL;
840 		}
841 
842 		/* restart interrupt endpoint */
843 		if (uac1->int_ep) {
844 			usb_ep_disable(uac1->int_ep);
845 			config_ep_by_speed(gadget, &audio->func, uac1->int_ep);
846 			usb_ep_enable(uac1->int_ep);
847 		}
848 
849 		return 0;
850 	}
851 
852 	if (intf == uac1->as_out_intf) {
853 		uac1->as_out_alt = alt;
854 
855 		if (alt)
856 			ret = u_audio_start_capture(&uac1->g_audio);
857 		else
858 			u_audio_stop_capture(&uac1->g_audio);
859 	} else if (intf == uac1->as_in_intf) {
860 		uac1->as_in_alt = alt;
861 
862 		if (alt)
863 			ret = u_audio_start_playback(&uac1->g_audio);
864 		else
865 			u_audio_stop_playback(&uac1->g_audio);
866 	} else {
867 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
868 		return -EINVAL;
869 	}
870 
871 	return ret;
872 }
873 
874 static int f_audio_get_alt(struct usb_function *f, unsigned intf)
875 {
876 	struct usb_composite_dev *cdev = f->config->cdev;
877 	struct usb_gadget *gadget = cdev->gadget;
878 	struct device *dev = &gadget->dev;
879 	struct f_uac1 *uac1 = func_to_uac1(f);
880 
881 	if (intf == uac1->ac_intf)
882 		return uac1->ac_alt;
883 	else if (intf == uac1->as_out_intf)
884 		return uac1->as_out_alt;
885 	else if (intf == uac1->as_in_intf)
886 		return uac1->as_in_alt;
887 	else
888 		dev_err(dev, "%s:%d Invalid Interface %d!\n",
889 			__func__, __LINE__, intf);
890 
891 	return -EINVAL;
892 }
893 
894 
895 static void f_audio_disable(struct usb_function *f)
896 {
897 	struct f_uac1 *uac1 = func_to_uac1(f);
898 
899 	uac1->as_out_alt = 0;
900 	uac1->as_in_alt = 0;
901 
902 	u_audio_stop_playback(&uac1->g_audio);
903 	u_audio_stop_capture(&uac1->g_audio);
904 	if (uac1->int_ep)
905 		usb_ep_disable(uac1->int_ep);
906 }
907 
908 /*-------------------------------------------------------------------------*/
909 static struct uac_feature_unit_descriptor *build_fu_desc(int chmask)
910 {
911 	struct uac_feature_unit_descriptor *fu_desc;
912 	int channels = num_channels(chmask);
913 	int fu_desc_size = UAC_DT_FEATURE_UNIT_SIZE(channels);
914 
915 	fu_desc = kzalloc(fu_desc_size, GFP_KERNEL);
916 	if (!fu_desc)
917 		return NULL;
918 
919 	fu_desc->bLength = fu_desc_size;
920 	fu_desc->bDescriptorType = USB_DT_CS_INTERFACE;
921 
922 	fu_desc->bDescriptorSubtype = UAC_FEATURE_UNIT;
923 	fu_desc->bControlSize  = 2;
924 
925 	/* bUnitID, bSourceID and bmaControls will be defined later */
926 
927 	return fu_desc;
928 }
929 
930 /* B.3.2  Class-Specific AC Interface Descriptor */
931 static struct
932 uac1_ac_header_descriptor *build_ac_header_desc(struct f_uac1_opts *opts)
933 {
934 	struct uac1_ac_header_descriptor *ac_desc;
935 	int ac_header_desc_size;
936 	int num_ifaces = 0;
937 
938 	if (EPOUT_EN(opts))
939 		num_ifaces++;
940 	if (EPIN_EN(opts))
941 		num_ifaces++;
942 
943 	ac_header_desc_size = UAC_DT_AC_HEADER_SIZE(num_ifaces);
944 
945 	ac_desc = kzalloc(ac_header_desc_size, GFP_KERNEL);
946 	if (!ac_desc)
947 		return NULL;
948 
949 	ac_desc->bLength = ac_header_desc_size;
950 	ac_desc->bDescriptorType = USB_DT_CS_INTERFACE;
951 	ac_desc->bDescriptorSubtype = UAC_HEADER;
952 	ac_desc->bcdADC = cpu_to_le16(0x0100);
953 	ac_desc->bInCollection = num_ifaces;
954 
955 	/* wTotalLength and baInterfaceNr will be defined later */
956 
957 	return ac_desc;
958 }
959 
960 /* Use macro to overcome line length limitation */
961 #define USBDHDR(p) (struct usb_descriptor_header *)(p)
962 
963 static void setup_descriptor(struct f_uac1_opts *opts)
964 {
965 	/* patch descriptors */
966 	int i = 1; /* ID's start with 1 */
967 
968 	if (EPOUT_EN(opts))
969 		usb_out_it_desc.bTerminalID = i++;
970 	if (EPIN_EN(opts))
971 		io_in_it_desc.bTerminalID = i++;
972 	if (EPOUT_EN(opts))
973 		io_out_ot_desc.bTerminalID = i++;
974 	if (EPIN_EN(opts))
975 		usb_in_ot_desc.bTerminalID = i++;
976 	if (FUOUT_EN(opts))
977 		out_feature_unit_desc->bUnitID = i++;
978 	if (FUIN_EN(opts))
979 		in_feature_unit_desc->bUnitID = i++;
980 
981 	if (FUIN_EN(opts)) {
982 		usb_in_ot_desc.bSourceID = in_feature_unit_desc->bUnitID;
983 		in_feature_unit_desc->bSourceID = io_in_it_desc.bTerminalID;
984 	} else {
985 		usb_in_ot_desc.bSourceID = io_in_it_desc.bTerminalID;
986 	}
987 	if (FUOUT_EN(opts)) {
988 		io_out_ot_desc.bSourceID = out_feature_unit_desc->bUnitID;
989 		out_feature_unit_desc->bSourceID = usb_out_it_desc.bTerminalID;
990 	} else {
991 		io_out_ot_desc.bSourceID = usb_out_it_desc.bTerminalID;
992 	}
993 
994 	as_out_header_desc.bTerminalLink = usb_out_it_desc.bTerminalID;
995 	as_in_header_desc.bTerminalLink = usb_in_ot_desc.bTerminalID;
996 
997 	ac_header_desc->wTotalLength = cpu_to_le16(ac_header_desc->bLength);
998 
999 	if (EPIN_EN(opts)) {
1000 		u16 len = le16_to_cpu(ac_header_desc->wTotalLength);
1001 
1002 		len += sizeof(usb_in_ot_desc);
1003 		len += sizeof(io_in_it_desc);
1004 		if (FUIN_EN(opts))
1005 			len += in_feature_unit_desc->bLength;
1006 		ac_header_desc->wTotalLength = cpu_to_le16(len);
1007 	}
1008 	if (EPOUT_EN(opts)) {
1009 		u16 len = le16_to_cpu(ac_header_desc->wTotalLength);
1010 
1011 		len += sizeof(usb_out_it_desc);
1012 		len += sizeof(io_out_ot_desc);
1013 		if (FUOUT_EN(opts))
1014 			len += out_feature_unit_desc->bLength;
1015 		ac_header_desc->wTotalLength = cpu_to_le16(len);
1016 	}
1017 
1018 	i = 0;
1019 	f_audio_desc[i++] = USBDHDR(&ac_interface_desc);
1020 	f_audio_desc[i++] = USBDHDR(ac_header_desc);
1021 
1022 	if (EPOUT_EN(opts)) {
1023 		f_audio_desc[i++] = USBDHDR(&usb_out_it_desc);
1024 		f_audio_desc[i++] = USBDHDR(&io_out_ot_desc);
1025 		if (FUOUT_EN(opts))
1026 			f_audio_desc[i++] = USBDHDR(out_feature_unit_desc);
1027 	}
1028 
1029 	if (EPIN_EN(opts)) {
1030 		f_audio_desc[i++] = USBDHDR(&io_in_it_desc);
1031 		f_audio_desc[i++] = USBDHDR(&usb_in_ot_desc);
1032 		if (FUIN_EN(opts))
1033 			f_audio_desc[i++] = USBDHDR(in_feature_unit_desc);
1034 	}
1035 
1036 	if (FUOUT_EN(opts) || FUIN_EN(opts))
1037 		f_audio_desc[i++] = USBDHDR(&ac_int_ep_desc);
1038 
1039 	if (EPOUT_EN(opts)) {
1040 		f_audio_desc[i++] = USBDHDR(&as_out_interface_alt_0_desc);
1041 		f_audio_desc[i++] = USBDHDR(&as_out_interface_alt_1_desc);
1042 		f_audio_desc[i++] = USBDHDR(&as_out_header_desc);
1043 		f_audio_desc[i++] = USBDHDR(&as_out_type_i_desc);
1044 		f_audio_desc[i++] = USBDHDR(&as_out_ep_desc);
1045 		f_audio_desc[i++] = USBDHDR(&as_iso_out_desc);
1046 	}
1047 	if (EPIN_EN(opts)) {
1048 		f_audio_desc[i++] = USBDHDR(&as_in_interface_alt_0_desc);
1049 		f_audio_desc[i++] = USBDHDR(&as_in_interface_alt_1_desc);
1050 		f_audio_desc[i++] = USBDHDR(&as_in_header_desc);
1051 		f_audio_desc[i++] = USBDHDR(&as_in_type_i_desc);
1052 		f_audio_desc[i++] = USBDHDR(&as_in_ep_desc);
1053 		f_audio_desc[i++] = USBDHDR(&as_iso_in_desc);
1054 	}
1055 	f_audio_desc[i] = NULL;
1056 }
1057 
1058 static int f_audio_validate_opts(struct g_audio *audio, struct device *dev)
1059 {
1060 	struct f_uac1_opts *opts = g_audio_to_uac1_opts(audio);
1061 
1062 	if (!opts->p_chmask && !opts->c_chmask) {
1063 		dev_err(dev, "Error: no playback and capture channels\n");
1064 		return -EINVAL;
1065 	} else if (opts->p_chmask & ~UAC1_CHANNEL_MASK) {
1066 		dev_err(dev, "Error: unsupported playback channels mask\n");
1067 		return -EINVAL;
1068 	} else if (opts->c_chmask & ~UAC1_CHANNEL_MASK) {
1069 		dev_err(dev, "Error: unsupported capture channels mask\n");
1070 		return -EINVAL;
1071 	} else if ((opts->p_ssize < 1) || (opts->p_ssize > 4)) {
1072 		dev_err(dev, "Error: incorrect playback sample size\n");
1073 		return -EINVAL;
1074 	} else if ((opts->c_ssize < 1) || (opts->c_ssize > 4)) {
1075 		dev_err(dev, "Error: incorrect capture sample size\n");
1076 		return -EINVAL;
1077 	} else if (!opts->p_srate) {
1078 		dev_err(dev, "Error: incorrect playback sampling rate\n");
1079 		return -EINVAL;
1080 	} else if (!opts->c_srate) {
1081 		dev_err(dev, "Error: incorrect capture sampling rate\n");
1082 		return -EINVAL;
1083 	}
1084 
1085 	if (opts->p_volume_max <= opts->p_volume_min) {
1086 		dev_err(dev, "Error: incorrect playback volume max/min\n");
1087 		return -EINVAL;
1088 	} else if (opts->c_volume_max <= opts->c_volume_min) {
1089 		dev_err(dev, "Error: incorrect capture volume max/min\n");
1090 		return -EINVAL;
1091 	} else if (opts->p_volume_res <= 0) {
1092 		dev_err(dev, "Error: negative/zero playback volume resolution\n");
1093 		return -EINVAL;
1094 	} else if (opts->c_volume_res <= 0) {
1095 		dev_err(dev, "Error: negative/zero capture volume resolution\n");
1096 		return -EINVAL;
1097 	}
1098 
1099 	if ((opts->p_volume_max - opts->p_volume_min) % opts->p_volume_res) {
1100 		dev_err(dev, "Error: incorrect playback volume resolution\n");
1101 		return -EINVAL;
1102 	} else if ((opts->c_volume_max - opts->c_volume_min) % opts->c_volume_res) {
1103 		dev_err(dev, "Error: incorrect capture volume resolution\n");
1104 		return -EINVAL;
1105 	}
1106 
1107 	return 0;
1108 }
1109 
1110 /* audio function driver setup/binding */
1111 static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
1112 {
1113 	struct usb_composite_dev	*cdev = c->cdev;
1114 	struct usb_gadget		*gadget = cdev->gadget;
1115 	struct device			*dev = &gadget->dev;
1116 	struct f_uac1			*uac1 = func_to_uac1(f);
1117 	struct g_audio			*audio = func_to_g_audio(f);
1118 	struct f_uac1_opts		*audio_opts;
1119 	struct usb_ep			*ep = NULL;
1120 	struct usb_string		*us;
1121 	u8				*sam_freq;
1122 	int				rate;
1123 	int				ba_iface_id;
1124 	int				status;
1125 
1126 	status = f_audio_validate_opts(audio, dev);
1127 	if (status)
1128 		return status;
1129 
1130 	audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst);
1131 
1132 	us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
1133 	if (IS_ERR(us))
1134 		return PTR_ERR(us);
1135 
1136 	ac_header_desc = build_ac_header_desc(audio_opts);
1137 	if (!ac_header_desc)
1138 		return -ENOMEM;
1139 
1140 	if (FUOUT_EN(audio_opts)) {
1141 		out_feature_unit_desc = build_fu_desc(audio_opts->c_chmask);
1142 		if (!out_feature_unit_desc) {
1143 			status = -ENOMEM;
1144 			goto fail;
1145 		}
1146 	}
1147 	if (FUIN_EN(audio_opts)) {
1148 		in_feature_unit_desc = build_fu_desc(audio_opts->p_chmask);
1149 		if (!in_feature_unit_desc) {
1150 			status = -ENOMEM;
1151 			goto err_free_fu;
1152 		}
1153 	}
1154 
1155 	ac_interface_desc.iInterface = us[STR_AC_IF].id;
1156 	usb_out_it_desc.iTerminal = us[STR_USB_OUT_IT].id;
1157 	usb_out_it_desc.iChannelNames = us[STR_USB_OUT_IT_CH_NAMES].id;
1158 	io_out_ot_desc.iTerminal = us[STR_IO_OUT_OT].id;
1159 	as_out_interface_alt_0_desc.iInterface = us[STR_AS_OUT_IF_ALT0].id;
1160 	as_out_interface_alt_1_desc.iInterface = us[STR_AS_OUT_IF_ALT1].id;
1161 	io_in_it_desc.iTerminal = us[STR_IO_IN_IT].id;
1162 	io_in_it_desc.iChannelNames = us[STR_IO_IN_IT_CH_NAMES].id;
1163 	usb_in_ot_desc.iTerminal = us[STR_USB_IN_OT].id;
1164 	as_in_interface_alt_0_desc.iInterface = us[STR_AS_IN_IF_ALT0].id;
1165 	as_in_interface_alt_1_desc.iInterface = us[STR_AS_IN_IF_ALT1].id;
1166 
1167 	if (FUOUT_EN(audio_opts)) {
1168 		u8 *i_feature;
1169 
1170 		i_feature = (u8 *)out_feature_unit_desc +
1171 					out_feature_unit_desc->bLength - 1;
1172 		*i_feature = us[STR_FU_OUT].id;
1173 	}
1174 	if (FUIN_EN(audio_opts)) {
1175 		u8 *i_feature;
1176 
1177 		i_feature = (u8 *)in_feature_unit_desc +
1178 					in_feature_unit_desc->bLength - 1;
1179 		*i_feature = us[STR_FU_IN].id;
1180 	}
1181 
1182 	/* Set channel numbers */
1183 	usb_out_it_desc.bNrChannels = num_channels(audio_opts->c_chmask);
1184 	usb_out_it_desc.wChannelConfig = cpu_to_le16(audio_opts->c_chmask);
1185 	as_out_type_i_desc.bNrChannels = num_channels(audio_opts->c_chmask);
1186 	as_out_type_i_desc.bSubframeSize = audio_opts->c_ssize;
1187 	as_out_type_i_desc.bBitResolution = audio_opts->c_ssize * 8;
1188 	io_in_it_desc.bNrChannels = num_channels(audio_opts->p_chmask);
1189 	io_in_it_desc.wChannelConfig = cpu_to_le16(audio_opts->p_chmask);
1190 	as_in_type_i_desc.bNrChannels = num_channels(audio_opts->p_chmask);
1191 	as_in_type_i_desc.bSubframeSize = audio_opts->p_ssize;
1192 	as_in_type_i_desc.bBitResolution = audio_opts->p_ssize * 8;
1193 
1194 	if (FUOUT_EN(audio_opts)) {
1195 		__le16 *bma = (__le16 *)&out_feature_unit_desc->bmaControls[0];
1196 		u32 control = 0;
1197 
1198 		if (audio_opts->c_mute_present)
1199 			control |= UAC_FU_MUTE;
1200 		if (audio_opts->c_volume_present)
1201 			control |= UAC_FU_VOLUME;
1202 		*bma = cpu_to_le16(control);
1203 	}
1204 	if (FUIN_EN(audio_opts)) {
1205 		__le16 *bma = (__le16 *)&in_feature_unit_desc->bmaControls[0];
1206 		u32 control = 0;
1207 
1208 		if (audio_opts->p_mute_present)
1209 			control |= UAC_FU_MUTE;
1210 		if (audio_opts->p_volume_present)
1211 			control |= UAC_FU_VOLUME;
1212 		*bma = cpu_to_le16(control);
1213 	}
1214 
1215 	/* Set sample rates */
1216 	rate = audio_opts->c_srate;
1217 	sam_freq = as_out_type_i_desc.tSamFreq[0];
1218 	memcpy(sam_freq, &rate, 3);
1219 	rate = audio_opts->p_srate;
1220 	sam_freq = as_in_type_i_desc.tSamFreq[0];
1221 	memcpy(sam_freq, &rate, 3);
1222 
1223 	/* allocate instance-specific interface IDs, and patch descriptors */
1224 	status = usb_interface_id(c, f);
1225 	if (status < 0)
1226 		goto err_free_fu;
1227 	ac_interface_desc.bInterfaceNumber = status;
1228 	uac1->ac_intf = status;
1229 	uac1->ac_alt = 0;
1230 
1231 	ba_iface_id = 0;
1232 
1233 	if (EPOUT_EN(audio_opts)) {
1234 		status = usb_interface_id(c, f);
1235 		if (status < 0)
1236 			goto err_free_fu;
1237 		as_out_interface_alt_0_desc.bInterfaceNumber = status;
1238 		as_out_interface_alt_1_desc.bInterfaceNumber = status;
1239 		ac_header_desc->baInterfaceNr[ba_iface_id++] = status;
1240 		uac1->as_out_intf = status;
1241 		uac1->as_out_alt = 0;
1242 	}
1243 
1244 	if (EPIN_EN(audio_opts)) {
1245 		status = usb_interface_id(c, f);
1246 		if (status < 0)
1247 			goto err_free_fu;
1248 		as_in_interface_alt_0_desc.bInterfaceNumber = status;
1249 		as_in_interface_alt_1_desc.bInterfaceNumber = status;
1250 		ac_header_desc->baInterfaceNr[ba_iface_id++] = status;
1251 		uac1->as_in_intf = status;
1252 		uac1->as_in_alt = 0;
1253 	}
1254 
1255 	audio->gadget = gadget;
1256 
1257 	status = -ENODEV;
1258 
1259 	ac_interface_desc.bNumEndpoints = 0;
1260 
1261 	/* allocate AC interrupt endpoint */
1262 	if (FUOUT_EN(audio_opts) || FUIN_EN(audio_opts)) {
1263 		ep = usb_ep_autoconfig(cdev->gadget, &ac_int_ep_desc);
1264 		if (!ep)
1265 			goto err_free_fu;
1266 		uac1->int_ep = ep;
1267 		uac1->int_ep->desc = &ac_int_ep_desc;
1268 
1269 		ac_interface_desc.bNumEndpoints = 1;
1270 	}
1271 
1272 	/* allocate instance-specific endpoints */
1273 	if (EPOUT_EN(audio_opts)) {
1274 		ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
1275 		if (!ep)
1276 			goto err_free_fu;
1277 		audio->out_ep = ep;
1278 		audio->out_ep->desc = &as_out_ep_desc;
1279 	}
1280 
1281 	if (EPIN_EN(audio_opts)) {
1282 		ep = usb_ep_autoconfig(cdev->gadget, &as_in_ep_desc);
1283 		if (!ep)
1284 			goto err_free_fu;
1285 		audio->in_ep = ep;
1286 		audio->in_ep->desc = &as_in_ep_desc;
1287 	}
1288 
1289 	setup_descriptor(audio_opts);
1290 
1291 	/* copy descriptors, and track endpoint copies */
1292 	status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
1293 					NULL);
1294 	if (status)
1295 		goto err_free_fu;
1296 
1297 	audio->out_ep_maxpsize = le16_to_cpu(as_out_ep_desc.wMaxPacketSize);
1298 	audio->in_ep_maxpsize = le16_to_cpu(as_in_ep_desc.wMaxPacketSize);
1299 	audio->params.c_chmask = audio_opts->c_chmask;
1300 	audio->params.c_srate = audio_opts->c_srate;
1301 	audio->params.c_ssize = audio_opts->c_ssize;
1302 	if (FUIN_EN(audio_opts)) {
1303 		audio->params.p_fu.id = USB_IN_FU_ID;
1304 		audio->params.p_fu.mute_present = audio_opts->p_mute_present;
1305 		audio->params.p_fu.volume_present =
1306 				audio_opts->p_volume_present;
1307 		audio->params.p_fu.volume_min = audio_opts->p_volume_min;
1308 		audio->params.p_fu.volume_max = audio_opts->p_volume_max;
1309 		audio->params.p_fu.volume_res = audio_opts->p_volume_res;
1310 	}
1311 	audio->params.p_chmask = audio_opts->p_chmask;
1312 	audio->params.p_srate = audio_opts->p_srate;
1313 	audio->params.p_ssize = audio_opts->p_ssize;
1314 	if (FUOUT_EN(audio_opts)) {
1315 		audio->params.c_fu.id = USB_OUT_FU_ID;
1316 		audio->params.c_fu.mute_present = audio_opts->c_mute_present;
1317 		audio->params.c_fu.volume_present =
1318 				audio_opts->c_volume_present;
1319 		audio->params.c_fu.volume_min = audio_opts->c_volume_min;
1320 		audio->params.c_fu.volume_max = audio_opts->c_volume_max;
1321 		audio->params.c_fu.volume_res = audio_opts->c_volume_res;
1322 	}
1323 	audio->params.req_number = audio_opts->req_number;
1324 	audio->params.fb_max = FBACK_FAST_MAX;
1325 	if (FUOUT_EN(audio_opts) || FUIN_EN(audio_opts))
1326 		audio->notify = audio_notify;
1327 
1328 	status = g_audio_setup(audio, "UAC1_PCM", "UAC1_Gadget");
1329 	if (status)
1330 		goto err_card_register;
1331 
1332 	return 0;
1333 
1334 err_card_register:
1335 	usb_free_all_descriptors(f);
1336 err_free_fu:
1337 	kfree(out_feature_unit_desc);
1338 	out_feature_unit_desc = NULL;
1339 	kfree(in_feature_unit_desc);
1340 	in_feature_unit_desc = NULL;
1341 fail:
1342 	kfree(ac_header_desc);
1343 	ac_header_desc = NULL;
1344 	return status;
1345 }
1346 
1347 /*-------------------------------------------------------------------------*/
1348 
1349 static inline struct f_uac1_opts *to_f_uac1_opts(struct config_item *item)
1350 {
1351 	return container_of(to_config_group(item), struct f_uac1_opts,
1352 			    func_inst.group);
1353 }
1354 
1355 static void f_uac1_attr_release(struct config_item *item)
1356 {
1357 	struct f_uac1_opts *opts = to_f_uac1_opts(item);
1358 
1359 	usb_put_function_instance(&opts->func_inst);
1360 }
1361 
1362 static struct configfs_item_operations f_uac1_item_ops = {
1363 	.release	= f_uac1_attr_release,
1364 };
1365 
1366 #define uac1_kstrtou32			kstrtou32
1367 #define uac1_kstrtos16			kstrtos16
1368 #define uac1_kstrtobool(s, base, res)	kstrtobool((s), (res))
1369 
1370 static const char *u32_fmt = "%u\n";
1371 static const char *s16_fmt = "%hd\n";
1372 static const char *bool_fmt = "%u\n";
1373 
1374 #define UAC1_ATTRIBUTE(type, name)					\
1375 static ssize_t f_uac1_opts_##name##_show(				\
1376 					  struct config_item *item,	\
1377 					  char *page)			\
1378 {									\
1379 	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
1380 	int result;							\
1381 									\
1382 	mutex_lock(&opts->lock);					\
1383 	result = sprintf(page, type##_fmt, opts->name);			\
1384 	mutex_unlock(&opts->lock);					\
1385 									\
1386 	return result;							\
1387 }									\
1388 									\
1389 static ssize_t f_uac1_opts_##name##_store(				\
1390 					  struct config_item *item,	\
1391 					  const char *page, size_t len)	\
1392 {									\
1393 	struct f_uac1_opts *opts = to_f_uac1_opts(item);		\
1394 	int ret;							\
1395 	type num;							\
1396 									\
1397 	mutex_lock(&opts->lock);					\
1398 	if (opts->refcnt) {						\
1399 		ret = -EBUSY;						\
1400 		goto end;						\
1401 	}								\
1402 									\
1403 	ret = uac1_kstrto##type(page, 0, &num);				\
1404 	if (ret)							\
1405 		goto end;						\
1406 									\
1407 	opts->name = num;						\
1408 	ret = len;							\
1409 									\
1410 end:									\
1411 	mutex_unlock(&opts->lock);					\
1412 	return ret;							\
1413 }									\
1414 									\
1415 CONFIGFS_ATTR(f_uac1_opts_, name)
1416 
1417 UAC1_ATTRIBUTE(u32, c_chmask);
1418 UAC1_ATTRIBUTE(u32, c_srate);
1419 UAC1_ATTRIBUTE(u32, c_ssize);
1420 UAC1_ATTRIBUTE(u32, p_chmask);
1421 UAC1_ATTRIBUTE(u32, p_srate);
1422 UAC1_ATTRIBUTE(u32, p_ssize);
1423 UAC1_ATTRIBUTE(u32, req_number);
1424 
1425 UAC1_ATTRIBUTE(bool, p_mute_present);
1426 UAC1_ATTRIBUTE(bool, p_volume_present);
1427 UAC1_ATTRIBUTE(s16, p_volume_min);
1428 UAC1_ATTRIBUTE(s16, p_volume_max);
1429 UAC1_ATTRIBUTE(s16, p_volume_res);
1430 
1431 UAC1_ATTRIBUTE(bool, c_mute_present);
1432 UAC1_ATTRIBUTE(bool, c_volume_present);
1433 UAC1_ATTRIBUTE(s16, c_volume_min);
1434 UAC1_ATTRIBUTE(s16, c_volume_max);
1435 UAC1_ATTRIBUTE(s16, c_volume_res);
1436 
1437 static struct configfs_attribute *f_uac1_attrs[] = {
1438 	&f_uac1_opts_attr_c_chmask,
1439 	&f_uac1_opts_attr_c_srate,
1440 	&f_uac1_opts_attr_c_ssize,
1441 	&f_uac1_opts_attr_p_chmask,
1442 	&f_uac1_opts_attr_p_srate,
1443 	&f_uac1_opts_attr_p_ssize,
1444 	&f_uac1_opts_attr_req_number,
1445 
1446 	&f_uac1_opts_attr_p_mute_present,
1447 	&f_uac1_opts_attr_p_volume_present,
1448 	&f_uac1_opts_attr_p_volume_min,
1449 	&f_uac1_opts_attr_p_volume_max,
1450 	&f_uac1_opts_attr_p_volume_res,
1451 
1452 	&f_uac1_opts_attr_c_mute_present,
1453 	&f_uac1_opts_attr_c_volume_present,
1454 	&f_uac1_opts_attr_c_volume_min,
1455 	&f_uac1_opts_attr_c_volume_max,
1456 	&f_uac1_opts_attr_c_volume_res,
1457 
1458 	NULL,
1459 };
1460 
1461 static const struct config_item_type f_uac1_func_type = {
1462 	.ct_item_ops	= &f_uac1_item_ops,
1463 	.ct_attrs	= f_uac1_attrs,
1464 	.ct_owner	= THIS_MODULE,
1465 };
1466 
1467 static void f_audio_free_inst(struct usb_function_instance *f)
1468 {
1469 	struct f_uac1_opts *opts;
1470 
1471 	opts = container_of(f, struct f_uac1_opts, func_inst);
1472 	kfree(opts);
1473 }
1474 
1475 static struct usb_function_instance *f_audio_alloc_inst(void)
1476 {
1477 	struct f_uac1_opts *opts;
1478 
1479 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1480 	if (!opts)
1481 		return ERR_PTR(-ENOMEM);
1482 
1483 	mutex_init(&opts->lock);
1484 	opts->func_inst.free_func_inst = f_audio_free_inst;
1485 
1486 	config_group_init_type_name(&opts->func_inst.group, "",
1487 				    &f_uac1_func_type);
1488 
1489 	opts->c_chmask = UAC1_DEF_CCHMASK;
1490 	opts->c_srate = UAC1_DEF_CSRATE;
1491 	opts->c_ssize = UAC1_DEF_CSSIZE;
1492 	opts->p_chmask = UAC1_DEF_PCHMASK;
1493 	opts->p_srate = UAC1_DEF_PSRATE;
1494 	opts->p_ssize = UAC1_DEF_PSSIZE;
1495 
1496 	opts->p_mute_present = UAC1_DEF_MUTE_PRESENT;
1497 	opts->p_volume_present = UAC1_DEF_VOLUME_PRESENT;
1498 	opts->p_volume_min = UAC1_DEF_MIN_DB;
1499 	opts->p_volume_max = UAC1_DEF_MAX_DB;
1500 	opts->p_volume_res = UAC1_DEF_RES_DB;
1501 
1502 	opts->c_mute_present = UAC1_DEF_MUTE_PRESENT;
1503 	opts->c_volume_present = UAC1_DEF_VOLUME_PRESENT;
1504 	opts->c_volume_min = UAC1_DEF_MIN_DB;
1505 	opts->c_volume_max = UAC1_DEF_MAX_DB;
1506 	opts->c_volume_res = UAC1_DEF_RES_DB;
1507 
1508 	opts->req_number = UAC1_DEF_REQ_NUM;
1509 	return &opts->func_inst;
1510 }
1511 
1512 static void f_audio_free(struct usb_function *f)
1513 {
1514 	struct g_audio *audio;
1515 	struct f_uac1_opts *opts;
1516 
1517 	audio = func_to_g_audio(f);
1518 	opts = container_of(f->fi, struct f_uac1_opts, func_inst);
1519 	kfree(audio);
1520 	mutex_lock(&opts->lock);
1521 	--opts->refcnt;
1522 	mutex_unlock(&opts->lock);
1523 }
1524 
1525 static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
1526 {
1527 	struct g_audio *audio = func_to_g_audio(f);
1528 
1529 	g_audio_cleanup(audio);
1530 	usb_free_all_descriptors(f);
1531 
1532 	kfree(out_feature_unit_desc);
1533 	out_feature_unit_desc = NULL;
1534 	kfree(in_feature_unit_desc);
1535 	in_feature_unit_desc = NULL;
1536 
1537 	kfree(ac_header_desc);
1538 	ac_header_desc = NULL;
1539 
1540 	audio->gadget = NULL;
1541 }
1542 
1543 static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
1544 {
1545 	struct f_uac1 *uac1;
1546 	struct f_uac1_opts *opts;
1547 
1548 	/* allocate and initialize one new instance */
1549 	uac1 = kzalloc(sizeof(*uac1), GFP_KERNEL);
1550 	if (!uac1)
1551 		return ERR_PTR(-ENOMEM);
1552 
1553 	opts = container_of(fi, struct f_uac1_opts, func_inst);
1554 	mutex_lock(&opts->lock);
1555 	++opts->refcnt;
1556 	mutex_unlock(&opts->lock);
1557 
1558 	uac1->g_audio.func.name = "uac1_func";
1559 	uac1->g_audio.func.bind = f_audio_bind;
1560 	uac1->g_audio.func.unbind = f_audio_unbind;
1561 	uac1->g_audio.func.set_alt = f_audio_set_alt;
1562 	uac1->g_audio.func.get_alt = f_audio_get_alt;
1563 	uac1->g_audio.func.setup = f_audio_setup;
1564 	uac1->g_audio.func.disable = f_audio_disable;
1565 	uac1->g_audio.func.free_func = f_audio_free;
1566 
1567 	return &uac1->g_audio.func;
1568 }
1569 
1570 DECLARE_USB_FUNCTION_INIT(uac1, f_audio_alloc_inst, f_audio_alloc);
1571 MODULE_LICENSE("GPL");
1572 MODULE_AUTHOR("Ruslan Bilovol");
1573