xref: /linux/drivers/usb/gadget/function/f_uac2.c (revision 3ea5eb68b9d624935108b5e696859304edfac202)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * f_uac2.c -- USB Audio Class 2.0 Function
4  *
5  * Copyright (C) 2011
6  *    Yadwinder Singh (yadi.brar01@gmail.com)
7  *    Jaswinder Singh (jaswinder.singh@linaro.org)
8  *
9  * Copyright (C) 2020
10  *    Ruslan Bilovol (ruslan.bilovol@gmail.com)
11  */
12 
13 #include <linux/usb/audio.h>
14 #include <linux/usb/audio-v2.h>
15 #include <linux/module.h>
16 
17 #include "u_audio.h"
18 
19 #include "u_uac2.h"
20 
21 /* UAC2 spec: 4.1 Audio Channel Cluster Descriptor */
22 #define UAC2_CHANNEL_MASK 0x07FFFFFF
23 
24 /*
25  * The driver implements a simple UAC_2 topology.
26  * USB-OUT -> IT_1 -> FU -> OT_3 -> ALSA_Capture
27  * ALSA_Playback -> IT_2 -> FU -> OT_4 -> USB-IN
28  * Capture and Playback sampling rates are independently
29  *  controlled by two clock sources :
30  *    CLK_5 := c_srate, and CLK_6 := p_srate
31  */
32 #define USB_OUT_CLK_ID	(out_clk_src_desc.bClockID)
33 #define USB_IN_CLK_ID	(in_clk_src_desc.bClockID)
34 #define USB_OUT_FU_ID	(out_feature_unit_desc->bUnitID)
35 #define USB_IN_FU_ID	(in_feature_unit_desc->bUnitID)
36 
37 #define CONTROL_ABSENT	0
38 #define CONTROL_RDONLY	1
39 #define CONTROL_RDWR	3
40 
41 #define CLK_FREQ_CTRL	0
42 #define CLK_VLD_CTRL	2
43 #define FU_MUTE_CTRL	0
44 #define FU_VOL_CTRL	2
45 
46 #define COPY_CTRL	0
47 #define CONN_CTRL	2
48 #define OVRLD_CTRL	4
49 #define CLSTR_CTRL	6
50 #define UNFLW_CTRL	8
51 #define OVFLW_CTRL	10
52 
53 #define EPIN_EN(_opts) ((_opts)->p_chmask != 0)
54 #define EPOUT_EN(_opts) ((_opts)->c_chmask != 0)
55 #define FUIN_EN(_opts) (EPIN_EN(_opts) \
56 				&& ((_opts)->p_mute_present \
57 				|| (_opts)->p_volume_present))
58 #define FUOUT_EN(_opts) (EPOUT_EN(_opts) \
59 				&& ((_opts)->c_mute_present \
60 				|| (_opts)->c_volume_present))
61 #define EPOUT_FBACK_IN_EN(_opts) ((_opts)->c_sync == USB_ENDPOINT_SYNC_ASYNC)
62 
63 struct f_uac2 {
64 	struct g_audio g_audio;
65 	u8 ac_intf, as_in_intf, as_out_intf;
66 	u8 ac_alt, as_in_alt, as_out_alt;	/* needed for get_alt() */
67 
68 	struct usb_ctrlrequest setup_cr;	/* will be used in data stage */
69 
70 	/* Interrupt IN endpoint of AC interface */
71 	struct usb_ep	*int_ep;
72 	atomic_t	int_count;
73 	/* transient state, only valid during handling of a single control request */
74 	int clock_id;
75 };
76 
77 static inline struct f_uac2 *func_to_uac2(struct usb_function *f)
78 {
79 	return container_of(f, struct f_uac2, g_audio.func);
80 }
81 
82 static inline
83 struct f_uac2_opts *g_audio_to_uac2_opts(struct g_audio *agdev)
84 {
85 	return container_of(agdev->func.fi, struct f_uac2_opts, func_inst);
86 }
87 
88 static int afunc_notify(struct g_audio *agdev, int unit_id, int cs);
89 
90 /* --------- USB Function Interface ------------- */
91 
92 enum {
93 	STR_ASSOC,
94 	STR_IF_CTRL,
95 	STR_CLKSRC_IN,
96 	STR_CLKSRC_OUT,
97 	STR_USB_IT,
98 	STR_USB_IT_CH,
99 	STR_IO_IT,
100 	STR_IO_IT_CH,
101 	STR_USB_OT,
102 	STR_IO_OT,
103 	STR_FU_IN,
104 	STR_FU_OUT,
105 	STR_AS_OUT_ALT0,
106 	STR_AS_OUT_ALT1,
107 	STR_AS_IN_ALT0,
108 	STR_AS_IN_ALT1,
109 	NUM_STR_DESCRIPTORS,
110 };
111 
112 static struct usb_string strings_fn[NUM_STR_DESCRIPTORS + 1] = {};
113 
114 static const char *const speed_names[] = {
115 	[USB_SPEED_UNKNOWN] = "UNKNOWN",
116 	[USB_SPEED_LOW] = "LS",
117 	[USB_SPEED_FULL] = "FS",
118 	[USB_SPEED_HIGH] = "HS",
119 	[USB_SPEED_WIRELESS] = "W",
120 	[USB_SPEED_SUPER] = "SS",
121 	[USB_SPEED_SUPER_PLUS] = "SS+",
122 };
123 
124 static struct usb_gadget_strings str_fn = {
125 	.language = 0x0409,	/* en-us */
126 	.strings = strings_fn,
127 };
128 
129 static struct usb_gadget_strings *fn_strings[] = {
130 	&str_fn,
131 	NULL,
132 };
133 
134 static struct usb_interface_assoc_descriptor iad_desc = {
135 	.bLength = sizeof iad_desc,
136 	.bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
137 
138 	.bFirstInterface = 0,
139 	.bInterfaceCount = 3,
140 	.bFunctionClass = USB_CLASS_AUDIO,
141 	.bFunctionSubClass = UAC2_FUNCTION_SUBCLASS_UNDEFINED,
142 	.bFunctionProtocol = UAC_VERSION_2,
143 };
144 
145 /* Audio Control Interface */
146 static struct usb_interface_descriptor std_ac_if_desc = {
147 	.bLength = sizeof std_ac_if_desc,
148 	.bDescriptorType = USB_DT_INTERFACE,
149 
150 	.bAlternateSetting = 0,
151 	/* .bNumEndpoints = DYNAMIC */
152 	.bInterfaceClass = USB_CLASS_AUDIO,
153 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
154 	.bInterfaceProtocol = UAC_VERSION_2,
155 };
156 
157 /* Clock source for IN traffic */
158 static struct uac_clock_source_descriptor in_clk_src_desc = {
159 	.bLength = sizeof in_clk_src_desc,
160 	.bDescriptorType = USB_DT_CS_INTERFACE,
161 
162 	.bDescriptorSubtype = UAC2_CLOCK_SOURCE,
163 	/* .bClockID = DYNAMIC */
164 	.bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
165 	.bmControls = (CONTROL_RDWR << CLK_FREQ_CTRL),
166 	.bAssocTerminal = 0,
167 };
168 
169 /* Clock source for OUT traffic */
170 static struct uac_clock_source_descriptor out_clk_src_desc = {
171 	.bLength = sizeof out_clk_src_desc,
172 	.bDescriptorType = USB_DT_CS_INTERFACE,
173 
174 	.bDescriptorSubtype = UAC2_CLOCK_SOURCE,
175 	/* .bClockID = DYNAMIC */
176 	.bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
177 	.bmControls = (CONTROL_RDWR << CLK_FREQ_CTRL),
178 	.bAssocTerminal = 0,
179 };
180 
181 /* Input Terminal for USB_OUT */
182 static struct uac2_input_terminal_descriptor usb_out_it_desc = {
183 	.bLength = sizeof usb_out_it_desc,
184 	.bDescriptorType = USB_DT_CS_INTERFACE,
185 
186 	.bDescriptorSubtype = UAC_INPUT_TERMINAL,
187 	/* .bTerminalID = DYNAMIC */
188 	.wTerminalType = cpu_to_le16(UAC_TERMINAL_STREAMING),
189 	.bAssocTerminal = 0,
190 	/* .bCSourceID = DYNAMIC */
191 	.iChannelNames = 0,
192 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
193 };
194 
195 /* Input Terminal for I/O-In */
196 static struct uac2_input_terminal_descriptor io_in_it_desc = {
197 	.bLength = sizeof io_in_it_desc,
198 	.bDescriptorType = USB_DT_CS_INTERFACE,
199 
200 	.bDescriptorSubtype = UAC_INPUT_TERMINAL,
201 	/* .bTerminalID = DYNAMIC */
202 	/* .wTerminalType = DYNAMIC */
203 	.bAssocTerminal = 0,
204 	/* .bCSourceID = DYNAMIC */
205 	.iChannelNames = 0,
206 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
207 };
208 
209 /* Ouput Terminal for USB_IN */
210 static struct uac2_output_terminal_descriptor usb_in_ot_desc = {
211 	.bLength = sizeof usb_in_ot_desc,
212 	.bDescriptorType = USB_DT_CS_INTERFACE,
213 
214 	.bDescriptorSubtype = UAC_OUTPUT_TERMINAL,
215 	/* .bTerminalID = DYNAMIC */
216 	.wTerminalType = cpu_to_le16(UAC_TERMINAL_STREAMING),
217 	.bAssocTerminal = 0,
218 	/* .bSourceID = DYNAMIC */
219 	/* .bCSourceID = DYNAMIC */
220 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
221 };
222 
223 /* Ouput Terminal for I/O-Out */
224 static struct uac2_output_terminal_descriptor io_out_ot_desc = {
225 	.bLength = sizeof io_out_ot_desc,
226 	.bDescriptorType = USB_DT_CS_INTERFACE,
227 
228 	.bDescriptorSubtype = UAC_OUTPUT_TERMINAL,
229 	/* .bTerminalID = DYNAMIC */
230 	/* .wTerminalType = DYNAMIC */
231 	.bAssocTerminal = 0,
232 	/* .bSourceID = DYNAMIC */
233 	/* .bCSourceID = DYNAMIC */
234 	.bmControls = cpu_to_le16(CONTROL_RDWR << COPY_CTRL),
235 };
236 
237 static struct uac2_feature_unit_descriptor *in_feature_unit_desc;
238 static struct uac2_feature_unit_descriptor *out_feature_unit_desc;
239 
240 static struct uac2_ac_header_descriptor ac_hdr_desc = {
241 	.bLength = sizeof ac_hdr_desc,
242 	.bDescriptorType = USB_DT_CS_INTERFACE,
243 
244 	.bDescriptorSubtype = UAC_MS_HEADER,
245 	.bcdADC = cpu_to_le16(0x200),
246 	.bCategory = UAC2_FUNCTION_IO_BOX,
247 	/* .wTotalLength = DYNAMIC */
248 	.bmControls = 0,
249 };
250 
251 /* AC IN Interrupt Endpoint */
252 static struct usb_endpoint_descriptor fs_ep_int_desc = {
253 	.bLength = USB_DT_ENDPOINT_SIZE,
254 	.bDescriptorType = USB_DT_ENDPOINT,
255 
256 	.bEndpointAddress = USB_DIR_IN,
257 	.bmAttributes = USB_ENDPOINT_XFER_INT,
258 	.wMaxPacketSize = cpu_to_le16(6),
259 	.bInterval = 1,
260 };
261 
262 static struct usb_endpoint_descriptor hs_ep_int_desc = {
263 	.bLength = USB_DT_ENDPOINT_SIZE,
264 	.bDescriptorType = USB_DT_ENDPOINT,
265 
266 	.bmAttributes = USB_ENDPOINT_XFER_INT,
267 	.wMaxPacketSize = cpu_to_le16(6),
268 	.bInterval = 4,
269 };
270 
271 static struct usb_endpoint_descriptor ss_ep_int_desc = {
272 	.bLength = USB_DT_ENDPOINT_SIZE,
273 	.bDescriptorType = USB_DT_ENDPOINT,
274 
275 	.bEndpointAddress = USB_DIR_IN,
276 	.bmAttributes = USB_ENDPOINT_XFER_INT,
277 	.wMaxPacketSize = cpu_to_le16(6),
278 	.bInterval = 4,
279 };
280 
281 static struct usb_ss_ep_comp_descriptor ss_ep_int_desc_comp = {
282 	.bLength = sizeof(ss_ep_int_desc_comp),
283 	.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
284 	.wBytesPerInterval = cpu_to_le16(6),
285 };
286 
287 /* Audio Streaming OUT Interface - Alt0 */
288 static struct usb_interface_descriptor std_as_out_if0_desc = {
289 	.bLength = sizeof std_as_out_if0_desc,
290 	.bDescriptorType = USB_DT_INTERFACE,
291 
292 	.bAlternateSetting = 0,
293 	.bNumEndpoints = 0,
294 	.bInterfaceClass = USB_CLASS_AUDIO,
295 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
296 	.bInterfaceProtocol = UAC_VERSION_2,
297 };
298 
299 /* Audio Streaming OUT Interface - Alt1 */
300 static struct usb_interface_descriptor std_as_out_if1_desc = {
301 	.bLength = sizeof std_as_out_if1_desc,
302 	.bDescriptorType = USB_DT_INTERFACE,
303 
304 	.bAlternateSetting = 1,
305 	.bNumEndpoints = 1,
306 	.bInterfaceClass = USB_CLASS_AUDIO,
307 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
308 	.bInterfaceProtocol = UAC_VERSION_2,
309 };
310 
311 /* Audio Stream OUT Intface Desc */
312 static struct uac2_as_header_descriptor as_out_hdr_desc = {
313 	.bLength = sizeof as_out_hdr_desc,
314 	.bDescriptorType = USB_DT_CS_INTERFACE,
315 
316 	.bDescriptorSubtype = UAC_AS_GENERAL,
317 	/* .bTerminalLink = DYNAMIC */
318 	.bmControls = 0,
319 	.bFormatType = UAC_FORMAT_TYPE_I,
320 	.bmFormats = cpu_to_le32(UAC_FORMAT_TYPE_I_PCM),
321 	.iChannelNames = 0,
322 };
323 
324 /* Audio USB_OUT Format */
325 static struct uac2_format_type_i_descriptor as_out_fmt1_desc = {
326 	.bLength = sizeof as_out_fmt1_desc,
327 	.bDescriptorType = USB_DT_CS_INTERFACE,
328 	.bDescriptorSubtype = UAC_FORMAT_TYPE,
329 	.bFormatType = UAC_FORMAT_TYPE_I,
330 };
331 
332 /* STD AS ISO OUT Endpoint */
333 static struct usb_endpoint_descriptor fs_epout_desc = {
334 	.bLength = USB_DT_ENDPOINT_SIZE,
335 	.bDescriptorType = USB_DT_ENDPOINT,
336 
337 	.bEndpointAddress = USB_DIR_OUT,
338 	/* .bmAttributes = DYNAMIC */
339 	/* .wMaxPacketSize = DYNAMIC */
340 	.bInterval = 1,
341 };
342 
343 static struct usb_endpoint_descriptor hs_epout_desc = {
344 	.bLength = USB_DT_ENDPOINT_SIZE,
345 	.bDescriptorType = USB_DT_ENDPOINT,
346 
347 	/* .bmAttributes = DYNAMIC */
348 	/* .wMaxPacketSize = DYNAMIC */
349 	/* .bInterval = DYNAMIC */
350 };
351 
352 static struct usb_endpoint_descriptor ss_epout_desc = {
353 	.bLength = USB_DT_ENDPOINT_SIZE,
354 	.bDescriptorType = USB_DT_ENDPOINT,
355 
356 	.bEndpointAddress = USB_DIR_OUT,
357 	/* .bmAttributes = DYNAMIC */
358 	/* .wMaxPacketSize = DYNAMIC */
359 	/* .bInterval = DYNAMIC */
360 };
361 
362 static struct usb_ss_ep_comp_descriptor ss_epout_desc_comp = {
363 	.bLength		= sizeof(ss_epout_desc_comp),
364 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
365 	.bMaxBurst		= 0,
366 	.bmAttributes		= 0,
367 	/* wBytesPerInterval = DYNAMIC */
368 };
369 
370 /* CS AS ISO OUT Endpoint */
371 static struct uac2_iso_endpoint_descriptor as_iso_out_desc = {
372 	.bLength = sizeof as_iso_out_desc,
373 	.bDescriptorType = USB_DT_CS_ENDPOINT,
374 
375 	.bDescriptorSubtype = UAC_EP_GENERAL,
376 	.bmAttributes = 0,
377 	.bmControls = 0,
378 	.bLockDelayUnits = 0,
379 	.wLockDelay = 0,
380 };
381 
382 /* STD AS ISO IN Feedback Endpoint */
383 static struct usb_endpoint_descriptor fs_epin_fback_desc = {
384 	.bLength = USB_DT_ENDPOINT_SIZE,
385 	.bDescriptorType = USB_DT_ENDPOINT,
386 
387 	.bEndpointAddress = USB_DIR_IN,
388 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
389 	.wMaxPacketSize = cpu_to_le16(3),
390 	.bInterval = 1,
391 };
392 
393 static struct usb_endpoint_descriptor hs_epin_fback_desc = {
394 	.bLength = USB_DT_ENDPOINT_SIZE,
395 	.bDescriptorType = USB_DT_ENDPOINT,
396 
397 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
398 	.wMaxPacketSize = cpu_to_le16(4),
399 	.bInterval = 4,
400 };
401 
402 static struct usb_endpoint_descriptor ss_epin_fback_desc = {
403 	.bLength = USB_DT_ENDPOINT_SIZE,
404 	.bDescriptorType = USB_DT_ENDPOINT,
405 
406 	.bEndpointAddress = USB_DIR_IN,
407 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_USAGE_FEEDBACK,
408 	.wMaxPacketSize = cpu_to_le16(4),
409 	.bInterval = 4,
410 };
411 
412 static struct usb_ss_ep_comp_descriptor ss_epin_fback_desc_comp = {
413 	.bLength		= sizeof(ss_epin_fback_desc_comp),
414 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
415 	.bMaxBurst		= 0,
416 	.bmAttributes		= 0,
417 	.wBytesPerInterval	= cpu_to_le16(4),
418 };
419 
420 
421 /* Audio Streaming IN Interface - Alt0 */
422 static struct usb_interface_descriptor std_as_in_if0_desc = {
423 	.bLength = sizeof std_as_in_if0_desc,
424 	.bDescriptorType = USB_DT_INTERFACE,
425 
426 	.bAlternateSetting = 0,
427 	.bNumEndpoints = 0,
428 	.bInterfaceClass = USB_CLASS_AUDIO,
429 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
430 	.bInterfaceProtocol = UAC_VERSION_2,
431 };
432 
433 /* Audio Streaming IN Interface - Alt1 */
434 static struct usb_interface_descriptor std_as_in_if1_desc = {
435 	.bLength = sizeof std_as_in_if1_desc,
436 	.bDescriptorType = USB_DT_INTERFACE,
437 
438 	.bAlternateSetting = 1,
439 	.bNumEndpoints = 1,
440 	.bInterfaceClass = USB_CLASS_AUDIO,
441 	.bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
442 	.bInterfaceProtocol = UAC_VERSION_2,
443 };
444 
445 /* Audio Stream IN Intface Desc */
446 static struct uac2_as_header_descriptor as_in_hdr_desc = {
447 	.bLength = sizeof as_in_hdr_desc,
448 	.bDescriptorType = USB_DT_CS_INTERFACE,
449 
450 	.bDescriptorSubtype = UAC_AS_GENERAL,
451 	/* .bTerminalLink = DYNAMIC */
452 	.bmControls = 0,
453 	.bFormatType = UAC_FORMAT_TYPE_I,
454 	.bmFormats = cpu_to_le32(UAC_FORMAT_TYPE_I_PCM),
455 	.iChannelNames = 0,
456 };
457 
458 /* Audio USB_IN Format */
459 static struct uac2_format_type_i_descriptor as_in_fmt1_desc = {
460 	.bLength = sizeof as_in_fmt1_desc,
461 	.bDescriptorType = USB_DT_CS_INTERFACE,
462 	.bDescriptorSubtype = UAC_FORMAT_TYPE,
463 	.bFormatType = UAC_FORMAT_TYPE_I,
464 };
465 
466 /* STD AS ISO IN Endpoint */
467 static struct usb_endpoint_descriptor fs_epin_desc = {
468 	.bLength = USB_DT_ENDPOINT_SIZE,
469 	.bDescriptorType = USB_DT_ENDPOINT,
470 
471 	.bEndpointAddress = USB_DIR_IN,
472 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
473 	/* .wMaxPacketSize = DYNAMIC */
474 	.bInterval = 1,
475 };
476 
477 static struct usb_endpoint_descriptor hs_epin_desc = {
478 	.bLength = USB_DT_ENDPOINT_SIZE,
479 	.bDescriptorType = USB_DT_ENDPOINT,
480 
481 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
482 	/* .wMaxPacketSize = DYNAMIC */
483 	/* .bInterval = DYNAMIC */
484 };
485 
486 static struct usb_endpoint_descriptor ss_epin_desc = {
487 	.bLength = USB_DT_ENDPOINT_SIZE,
488 	.bDescriptorType = USB_DT_ENDPOINT,
489 
490 	.bEndpointAddress = USB_DIR_IN,
491 	.bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
492 	/* .wMaxPacketSize = DYNAMIC */
493 	/* .bInterval = DYNAMIC */
494 };
495 
496 static struct usb_ss_ep_comp_descriptor ss_epin_desc_comp = {
497 	.bLength		= sizeof(ss_epin_desc_comp),
498 	.bDescriptorType	= USB_DT_SS_ENDPOINT_COMP,
499 	.bMaxBurst		= 0,
500 	.bmAttributes		= 0,
501 	/* wBytesPerInterval = DYNAMIC */
502 };
503 
504 /* CS AS ISO IN Endpoint */
505 static struct uac2_iso_endpoint_descriptor as_iso_in_desc = {
506 	.bLength = sizeof as_iso_in_desc,
507 	.bDescriptorType = USB_DT_CS_ENDPOINT,
508 
509 	.bDescriptorSubtype = UAC_EP_GENERAL,
510 	.bmAttributes = 0,
511 	.bmControls = 0,
512 	.bLockDelayUnits = 0,
513 	.wLockDelay = 0,
514 };
515 
516 static struct usb_descriptor_header *fs_audio_desc[] = {
517 	(struct usb_descriptor_header *)&iad_desc,
518 	(struct usb_descriptor_header *)&std_ac_if_desc,
519 
520 	(struct usb_descriptor_header *)&ac_hdr_desc,
521 	(struct usb_descriptor_header *)&in_clk_src_desc,
522 	(struct usb_descriptor_header *)&out_clk_src_desc,
523 	(struct usb_descriptor_header *)&usb_out_it_desc,
524 	(struct usb_descriptor_header *)&out_feature_unit_desc,
525 	(struct usb_descriptor_header *)&io_in_it_desc,
526 	(struct usb_descriptor_header *)&usb_in_ot_desc,
527 	(struct usb_descriptor_header *)&in_feature_unit_desc,
528 	(struct usb_descriptor_header *)&io_out_ot_desc,
529 
530 	(struct usb_descriptor_header *)&fs_ep_int_desc,
531 
532 	(struct usb_descriptor_header *)&std_as_out_if0_desc,
533 	(struct usb_descriptor_header *)&std_as_out_if1_desc,
534 
535 	(struct usb_descriptor_header *)&as_out_hdr_desc,
536 	(struct usb_descriptor_header *)&as_out_fmt1_desc,
537 	(struct usb_descriptor_header *)&fs_epout_desc,
538 	(struct usb_descriptor_header *)&as_iso_out_desc,
539 	(struct usb_descriptor_header *)&fs_epin_fback_desc,
540 
541 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
542 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
543 
544 	(struct usb_descriptor_header *)&as_in_hdr_desc,
545 	(struct usb_descriptor_header *)&as_in_fmt1_desc,
546 	(struct usb_descriptor_header *)&fs_epin_desc,
547 	(struct usb_descriptor_header *)&as_iso_in_desc,
548 	NULL,
549 };
550 
551 static struct usb_descriptor_header *hs_audio_desc[] = {
552 	(struct usb_descriptor_header *)&iad_desc,
553 	(struct usb_descriptor_header *)&std_ac_if_desc,
554 
555 	(struct usb_descriptor_header *)&ac_hdr_desc,
556 	(struct usb_descriptor_header *)&in_clk_src_desc,
557 	(struct usb_descriptor_header *)&out_clk_src_desc,
558 	(struct usb_descriptor_header *)&usb_out_it_desc,
559 	(struct usb_descriptor_header *)&out_feature_unit_desc,
560 	(struct usb_descriptor_header *)&io_in_it_desc,
561 	(struct usb_descriptor_header *)&usb_in_ot_desc,
562 	(struct usb_descriptor_header *)&in_feature_unit_desc,
563 	(struct usb_descriptor_header *)&io_out_ot_desc,
564 
565 	(struct usb_descriptor_header *)&hs_ep_int_desc,
566 
567 	(struct usb_descriptor_header *)&std_as_out_if0_desc,
568 	(struct usb_descriptor_header *)&std_as_out_if1_desc,
569 
570 	(struct usb_descriptor_header *)&as_out_hdr_desc,
571 	(struct usb_descriptor_header *)&as_out_fmt1_desc,
572 	(struct usb_descriptor_header *)&hs_epout_desc,
573 	(struct usb_descriptor_header *)&as_iso_out_desc,
574 	(struct usb_descriptor_header *)&hs_epin_fback_desc,
575 
576 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
577 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
578 
579 	(struct usb_descriptor_header *)&as_in_hdr_desc,
580 	(struct usb_descriptor_header *)&as_in_fmt1_desc,
581 	(struct usb_descriptor_header *)&hs_epin_desc,
582 	(struct usb_descriptor_header *)&as_iso_in_desc,
583 	NULL,
584 };
585 
586 static struct usb_descriptor_header *ss_audio_desc[] = {
587 	(struct usb_descriptor_header *)&iad_desc,
588 	(struct usb_descriptor_header *)&std_ac_if_desc,
589 
590 	(struct usb_descriptor_header *)&ac_hdr_desc,
591 	(struct usb_descriptor_header *)&in_clk_src_desc,
592 	(struct usb_descriptor_header *)&out_clk_src_desc,
593 	(struct usb_descriptor_header *)&usb_out_it_desc,
594   (struct usb_descriptor_header *)&out_feature_unit_desc,
595 	(struct usb_descriptor_header *)&io_in_it_desc,
596 	(struct usb_descriptor_header *)&usb_in_ot_desc,
597 	(struct usb_descriptor_header *)&in_feature_unit_desc,
598 	(struct usb_descriptor_header *)&io_out_ot_desc,
599 
600 	(struct usb_descriptor_header *)&ss_ep_int_desc,
601 	(struct usb_descriptor_header *)&ss_ep_int_desc_comp,
602 
603 	(struct usb_descriptor_header *)&std_as_out_if0_desc,
604 	(struct usb_descriptor_header *)&std_as_out_if1_desc,
605 
606 	(struct usb_descriptor_header *)&as_out_hdr_desc,
607 	(struct usb_descriptor_header *)&as_out_fmt1_desc,
608 	(struct usb_descriptor_header *)&ss_epout_desc,
609 	(struct usb_descriptor_header *)&ss_epout_desc_comp,
610 	(struct usb_descriptor_header *)&as_iso_out_desc,
611 	(struct usb_descriptor_header *)&ss_epin_fback_desc,
612 	(struct usb_descriptor_header *)&ss_epin_fback_desc_comp,
613 
614 	(struct usb_descriptor_header *)&std_as_in_if0_desc,
615 	(struct usb_descriptor_header *)&std_as_in_if1_desc,
616 
617 	(struct usb_descriptor_header *)&as_in_hdr_desc,
618 	(struct usb_descriptor_header *)&as_in_fmt1_desc,
619 	(struct usb_descriptor_header *)&ss_epin_desc,
620 	(struct usb_descriptor_header *)&ss_epin_desc_comp,
621 	(struct usb_descriptor_header *)&as_iso_in_desc,
622 	NULL,
623 };
624 
625 struct cntrl_cur_lay2 {
626 	__le16	wCUR;
627 };
628 
629 struct cntrl_range_lay2 {
630 	__le16	wNumSubRanges;
631 	__le16	wMIN;
632 	__le16	wMAX;
633 	__le16	wRES;
634 } __packed;
635 
636 struct cntrl_cur_lay3 {
637 	__le32	dCUR;
638 };
639 
640 struct cntrl_subrange_lay3 {
641 	__le32	dMIN;
642 	__le32	dMAX;
643 	__le32	dRES;
644 } __packed;
645 
646 #define ranges_lay3_size(c) (sizeof(c.wNumSubRanges)	\
647 		+ le16_to_cpu(c.wNumSubRanges)		\
648 		* sizeof(struct cntrl_subrange_lay3))
649 
650 #define DECLARE_UAC2_CNTRL_RANGES_LAY3(k, n)		\
651 	struct cntrl_ranges_lay3_##k {			\
652 	__le16	wNumSubRanges;				\
653 	struct cntrl_subrange_lay3 r[n];		\
654 } __packed
655 
656 DECLARE_UAC2_CNTRL_RANGES_LAY3(srates, UAC_MAX_RATES);
657 
658 static int get_max_srate(const int *srates)
659 {
660 	int i, max_srate = 0;
661 
662 	for (i = 0; i < UAC_MAX_RATES; i++) {
663 		if (srates[i] == 0)
664 			break;
665 		if (srates[i] > max_srate)
666 			max_srate = srates[i];
667 	}
668 	return max_srate;
669 }
670 
671 static int get_max_bw_for_bint(const struct f_uac2_opts *uac2_opts,
672 	u8 bint, unsigned int factor, bool is_playback)
673 {
674 	int chmask, srate, ssize;
675 	u16 max_size_bw;
676 
677 	if (is_playback) {
678 		chmask = uac2_opts->p_chmask;
679 		srate = get_max_srate(uac2_opts->p_srates);
680 		ssize = uac2_opts->p_ssize;
681 	} else {
682 		chmask = uac2_opts->c_chmask;
683 		srate = get_max_srate(uac2_opts->c_srates);
684 		ssize = uac2_opts->c_ssize;
685 	}
686 
687 	if (is_playback || (uac2_opts->c_sync == USB_ENDPOINT_SYNC_ASYNC)) {
688 		// playback is always async, capture only when configured
689 		// Win10 requires max packet size + 1 frame
690 		srate = srate * (1000 + uac2_opts->fb_max) / 1000;
691 		// updated srate is always bigger, therefore DIV_ROUND_UP always yields +1
692 		max_size_bw = num_channels(chmask) * ssize *
693 			(DIV_ROUND_UP(srate, factor / (1 << (bint - 1))));
694 	} else {
695 		// adding 1 frame provision for Win10
696 		max_size_bw = num_channels(chmask) * ssize *
697 			(DIV_ROUND_UP(srate, factor / (1 << (bint - 1))) + 1);
698 	}
699 	return max_size_bw;
700 }
701 
702 static int set_ep_max_packet_size_bint(struct device *dev, const struct f_uac2_opts *uac2_opts,
703 	struct usb_endpoint_descriptor *ep_desc,
704 	enum usb_device_speed speed, bool is_playback)
705 {
706 	u16 max_size_bw, max_size_ep;
707 	u8 bint, opts_bint;
708 	char *dir;
709 
710 	switch (speed) {
711 	case USB_SPEED_FULL:
712 		max_size_ep = 1023;
713 		// fixed
714 		bint = ep_desc->bInterval;
715 		max_size_bw = get_max_bw_for_bint(uac2_opts, bint, 1000, is_playback);
716 		break;
717 
718 	case USB_SPEED_HIGH:
719 	case USB_SPEED_SUPER:
720 		max_size_ep = 1024;
721 		if (is_playback)
722 			opts_bint = uac2_opts->p_hs_bint;
723 		else
724 			opts_bint = uac2_opts->c_hs_bint;
725 
726 		if (opts_bint > 0) {
727 			/* fixed bint */
728 			bint = opts_bint;
729 			max_size_bw = get_max_bw_for_bint(uac2_opts, bint, 8000, is_playback);
730 		} else {
731 			/* checking bInterval from 4 to 1 whether the required bandwidth fits */
732 			for (bint = 4; bint > 0; --bint) {
733 				max_size_bw = get_max_bw_for_bint(
734 					uac2_opts, bint, 8000, is_playback);
735 				if (max_size_bw <= max_size_ep)
736 					break;
737 			}
738 		}
739 		break;
740 
741 	default:
742 		return -EINVAL;
743 	}
744 
745 	if (is_playback)
746 		dir = "Playback";
747 	else
748 		dir = "Capture";
749 
750 	if (max_size_bw <= max_size_ep)
751 		dev_dbg(dev,
752 			"%s %s: Would use wMaxPacketSize %d and bInterval %d\n",
753 			speed_names[speed], dir, max_size_bw, bint);
754 	else {
755 		dev_warn(dev,
756 			"%s %s: Req. wMaxPacketSize %d at bInterval %d > max ISOC %d, may drop data!\n",
757 			speed_names[speed], dir, max_size_bw, bint, max_size_ep);
758 		max_size_bw = max_size_ep;
759 	}
760 
761 	ep_desc->wMaxPacketSize = cpu_to_le16(max_size_bw);
762 	ep_desc->bInterval = bint;
763 
764 	return 0;
765 }
766 
767 static struct uac2_feature_unit_descriptor *build_fu_desc(int chmask)
768 {
769 	struct uac2_feature_unit_descriptor *fu_desc;
770 	int channels = num_channels(chmask);
771 	int fu_desc_size = UAC2_DT_FEATURE_UNIT_SIZE(channels);
772 
773 	fu_desc = kzalloc(fu_desc_size, GFP_KERNEL);
774 	if (!fu_desc)
775 		return NULL;
776 
777 	fu_desc->bLength = fu_desc_size;
778 	fu_desc->bDescriptorType = USB_DT_CS_INTERFACE;
779 
780 	fu_desc->bDescriptorSubtype = UAC_FEATURE_UNIT;
781 
782 	/* bUnitID, bSourceID and bmaControls will be defined later */
783 
784 	return fu_desc;
785 }
786 
787 /* Use macro to overcome line length limitation */
788 #define USBDHDR(p) (struct usb_descriptor_header *)(p)
789 
790 static void setup_headers(struct f_uac2_opts *opts,
791 			  struct usb_descriptor_header **headers,
792 			  enum usb_device_speed speed)
793 {
794 	struct usb_ss_ep_comp_descriptor *epout_desc_comp = NULL;
795 	struct usb_ss_ep_comp_descriptor *epin_desc_comp = NULL;
796 	struct usb_ss_ep_comp_descriptor *epin_fback_desc_comp = NULL;
797 	struct usb_ss_ep_comp_descriptor *ep_int_desc_comp = NULL;
798 	struct usb_endpoint_descriptor *epout_desc;
799 	struct usb_endpoint_descriptor *epin_desc;
800 	struct usb_endpoint_descriptor *epin_fback_desc;
801 	struct usb_endpoint_descriptor *ep_int_desc;
802 	int i;
803 
804 	switch (speed) {
805 	case USB_SPEED_FULL:
806 		epout_desc = &fs_epout_desc;
807 		epin_desc = &fs_epin_desc;
808 		epin_fback_desc = &fs_epin_fback_desc;
809 		ep_int_desc = &fs_ep_int_desc;
810 		break;
811 	case USB_SPEED_HIGH:
812 		epout_desc = &hs_epout_desc;
813 		epin_desc = &hs_epin_desc;
814 		epin_fback_desc = &hs_epin_fback_desc;
815 		ep_int_desc = &hs_ep_int_desc;
816 		break;
817 	default:
818 		epout_desc = &ss_epout_desc;
819 		epin_desc = &ss_epin_desc;
820 		epout_desc_comp = &ss_epout_desc_comp;
821 		epin_desc_comp = &ss_epin_desc_comp;
822 		epin_fback_desc = &ss_epin_fback_desc;
823 		epin_fback_desc_comp = &ss_epin_fback_desc_comp;
824 		ep_int_desc = &ss_ep_int_desc;
825 		ep_int_desc_comp = &ss_ep_int_desc_comp;
826 	}
827 
828 	i = 0;
829 	headers[i++] = USBDHDR(&iad_desc);
830 	headers[i++] = USBDHDR(&std_ac_if_desc);
831 	headers[i++] = USBDHDR(&ac_hdr_desc);
832 	if (EPIN_EN(opts))
833 		headers[i++] = USBDHDR(&in_clk_src_desc);
834 	if (EPOUT_EN(opts)) {
835 		headers[i++] = USBDHDR(&out_clk_src_desc);
836 		headers[i++] = USBDHDR(&usb_out_it_desc);
837 
838 		if (FUOUT_EN(opts))
839 			headers[i++] = USBDHDR(out_feature_unit_desc);
840 	}
841 
842 	if (EPIN_EN(opts)) {
843 		headers[i++] = USBDHDR(&io_in_it_desc);
844 
845 		if (FUIN_EN(opts))
846 			headers[i++] = USBDHDR(in_feature_unit_desc);
847 
848 		headers[i++] = USBDHDR(&usb_in_ot_desc);
849 	}
850 
851 	if (EPOUT_EN(opts))
852 		headers[i++] = USBDHDR(&io_out_ot_desc);
853 
854 	if (FUOUT_EN(opts) || FUIN_EN(opts)) {
855 		headers[i++] = USBDHDR(ep_int_desc);
856 		if (ep_int_desc_comp)
857 			headers[i++] = USBDHDR(ep_int_desc_comp);
858 	}
859 
860 	if (EPOUT_EN(opts)) {
861 		headers[i++] = USBDHDR(&std_as_out_if0_desc);
862 		headers[i++] = USBDHDR(&std_as_out_if1_desc);
863 		headers[i++] = USBDHDR(&as_out_hdr_desc);
864 		headers[i++] = USBDHDR(&as_out_fmt1_desc);
865 		headers[i++] = USBDHDR(epout_desc);
866 		if (epout_desc_comp)
867 			headers[i++] = USBDHDR(epout_desc_comp);
868 
869 		headers[i++] = USBDHDR(&as_iso_out_desc);
870 
871 		if (EPOUT_FBACK_IN_EN(opts)) {
872 			headers[i++] = USBDHDR(epin_fback_desc);
873 			if (epin_fback_desc_comp)
874 				headers[i++] = USBDHDR(epin_fback_desc_comp);
875 		}
876 	}
877 
878 	if (EPIN_EN(opts)) {
879 		headers[i++] = USBDHDR(&std_as_in_if0_desc);
880 		headers[i++] = USBDHDR(&std_as_in_if1_desc);
881 		headers[i++] = USBDHDR(&as_in_hdr_desc);
882 		headers[i++] = USBDHDR(&as_in_fmt1_desc);
883 		headers[i++] = USBDHDR(epin_desc);
884 		if (epin_desc_comp)
885 			headers[i++] = USBDHDR(epin_desc_comp);
886 
887 		headers[i++] = USBDHDR(&as_iso_in_desc);
888 	}
889 	headers[i] = NULL;
890 }
891 
892 static void setup_descriptor(struct f_uac2_opts *opts)
893 {
894 	/* patch descriptors */
895 	int i = 1; /* ID's start with 1 */
896 
897 	if (EPOUT_EN(opts))
898 		usb_out_it_desc.bTerminalID = i++;
899 	if (EPIN_EN(opts))
900 		io_in_it_desc.bTerminalID = i++;
901 	if (EPOUT_EN(opts))
902 		io_out_ot_desc.bTerminalID = i++;
903 	if (EPIN_EN(opts))
904 		usb_in_ot_desc.bTerminalID = i++;
905 	if (FUOUT_EN(opts))
906 		out_feature_unit_desc->bUnitID = i++;
907 	if (FUIN_EN(opts))
908 		in_feature_unit_desc->bUnitID = i++;
909 	if (EPOUT_EN(opts))
910 		out_clk_src_desc.bClockID = i++;
911 	if (EPIN_EN(opts))
912 		in_clk_src_desc.bClockID = i++;
913 
914 	usb_out_it_desc.bCSourceID = out_clk_src_desc.bClockID;
915 
916 	if (FUIN_EN(opts)) {
917 		usb_in_ot_desc.bSourceID = in_feature_unit_desc->bUnitID;
918 		in_feature_unit_desc->bSourceID = io_in_it_desc.bTerminalID;
919 	} else {
920 		usb_in_ot_desc.bSourceID = io_in_it_desc.bTerminalID;
921 	}
922 
923 	usb_in_ot_desc.bCSourceID = in_clk_src_desc.bClockID;
924 	io_in_it_desc.bCSourceID = in_clk_src_desc.bClockID;
925 	io_out_ot_desc.bCSourceID = out_clk_src_desc.bClockID;
926 
927 	if (FUOUT_EN(opts)) {
928 		io_out_ot_desc.bSourceID = out_feature_unit_desc->bUnitID;
929 		out_feature_unit_desc->bSourceID = usb_out_it_desc.bTerminalID;
930 	} else {
931 		io_out_ot_desc.bSourceID = usb_out_it_desc.bTerminalID;
932 	}
933 
934 	as_out_hdr_desc.bTerminalLink = usb_out_it_desc.bTerminalID;
935 	as_in_hdr_desc.bTerminalLink = usb_in_ot_desc.bTerminalID;
936 
937 	iad_desc.bInterfaceCount = 1;
938 	ac_hdr_desc.wTotalLength = cpu_to_le16(sizeof(ac_hdr_desc));
939 
940 	if (EPIN_EN(opts)) {
941 		u16 len = le16_to_cpu(ac_hdr_desc.wTotalLength);
942 
943 		len += sizeof(in_clk_src_desc);
944 		len += sizeof(usb_in_ot_desc);
945 
946 		if (FUIN_EN(opts))
947 			len += in_feature_unit_desc->bLength;
948 
949 		len += sizeof(io_in_it_desc);
950 		ac_hdr_desc.wTotalLength = cpu_to_le16(len);
951 		iad_desc.bInterfaceCount++;
952 	}
953 	if (EPOUT_EN(opts)) {
954 		u16 len = le16_to_cpu(ac_hdr_desc.wTotalLength);
955 
956 		len += sizeof(out_clk_src_desc);
957 		len += sizeof(usb_out_it_desc);
958 
959 		if (FUOUT_EN(opts))
960 			len += out_feature_unit_desc->bLength;
961 
962 		len += sizeof(io_out_ot_desc);
963 		ac_hdr_desc.wTotalLength = cpu_to_le16(len);
964 		iad_desc.bInterfaceCount++;
965 	}
966 
967 	io_in_it_desc.wTerminalType = cpu_to_le16(opts->c_terminal_type);
968 	io_out_ot_desc.wTerminalType = cpu_to_le16(opts->p_terminal_type);
969 
970 	setup_headers(opts, fs_audio_desc, USB_SPEED_FULL);
971 	setup_headers(opts, hs_audio_desc, USB_SPEED_HIGH);
972 	setup_headers(opts, ss_audio_desc, USB_SPEED_SUPER);
973 }
974 
975 static int afunc_validate_opts(struct g_audio *agdev, struct device *dev)
976 {
977 	struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev);
978 	const char *msg = NULL;
979 
980 	if (!opts->p_chmask && !opts->c_chmask)
981 		msg = "no playback and capture channels";
982 	else if (opts->p_chmask & ~UAC2_CHANNEL_MASK)
983 		msg = "unsupported playback channels mask";
984 	else if (opts->c_chmask & ~UAC2_CHANNEL_MASK)
985 		msg = "unsupported capture channels mask";
986 	else if ((opts->p_ssize < 1) || (opts->p_ssize > 4))
987 		msg = "incorrect playback sample size";
988 	else if ((opts->c_ssize < 1) || (opts->c_ssize > 4))
989 		msg = "incorrect capture sample size";
990 	else if (!opts->p_srates[0])
991 		msg = "incorrect playback sampling rate";
992 	else if (!opts->c_srates[0])
993 		msg = "incorrect capture sampling rate";
994 
995 	else if (opts->p_volume_max <= opts->p_volume_min)
996 		msg = "incorrect playback volume max/min";
997 	else if (opts->c_volume_max <= opts->c_volume_min)
998 		msg = "incorrect capture volume max/min";
999 	else if (opts->p_volume_res <= 0)
1000 		msg = "negative/zero playback volume resolution";
1001 	else if (opts->c_volume_res <= 0)
1002 		msg = "negative/zero capture volume resolution";
1003 
1004 	else if ((opts->p_volume_max - opts->p_volume_min) % opts->p_volume_res)
1005 		msg = "incorrect playback volume resolution";
1006 	else if ((opts->c_volume_max - opts->c_volume_min) % opts->c_volume_res)
1007 		msg = "incorrect capture volume resolution";
1008 
1009 	else if ((opts->p_hs_bint < 0) || (opts->p_hs_bint > 4))
1010 		msg = "incorrect playback HS/SS bInterval (1-4: fixed, 0: auto)";
1011 	else if ((opts->c_hs_bint < 0) || (opts->c_hs_bint > 4))
1012 		msg = "incorrect capture HS/SS bInterval (1-4: fixed, 0: auto)";
1013 
1014 	if (msg) {
1015 		dev_err(dev, "Error: %s\n", msg);
1016 		return -EINVAL;
1017 	}
1018 
1019 	return 0;
1020 }
1021 
1022 static int
1023 afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
1024 {
1025 	struct f_uac2 *uac2 = func_to_uac2(fn);
1026 	struct g_audio *agdev = func_to_g_audio(fn);
1027 	struct usb_composite_dev *cdev = cfg->cdev;
1028 	struct usb_gadget *gadget = cdev->gadget;
1029 	struct device *dev = &gadget->dev;
1030 	struct f_uac2_opts *uac2_opts = g_audio_to_uac2_opts(agdev);
1031 	struct usb_string *us;
1032 	int ret;
1033 
1034 	ret = afunc_validate_opts(agdev, dev);
1035 	if (ret)
1036 		return ret;
1037 
1038 	strings_fn[STR_ASSOC].s = uac2_opts->function_name;
1039 	strings_fn[STR_IF_CTRL].s = uac2_opts->if_ctrl_name;
1040 	strings_fn[STR_CLKSRC_IN].s = uac2_opts->clksrc_in_name;
1041 	strings_fn[STR_CLKSRC_OUT].s = uac2_opts->clksrc_out_name;
1042 
1043 	strings_fn[STR_USB_IT].s = uac2_opts->c_it_name;
1044 	strings_fn[STR_USB_IT_CH].s = uac2_opts->c_it_ch_name;
1045 	strings_fn[STR_IO_OT].s = uac2_opts->c_ot_name;
1046 	strings_fn[STR_FU_OUT].s = uac2_opts->c_fu_vol_name;
1047 	strings_fn[STR_AS_OUT_ALT0].s = "Playback Inactive";
1048 	strings_fn[STR_AS_OUT_ALT1].s = "Playback Active";
1049 
1050 	strings_fn[STR_IO_IT].s = uac2_opts->p_it_name;
1051 	strings_fn[STR_IO_IT_CH].s = uac2_opts->p_it_ch_name;
1052 	strings_fn[STR_USB_OT].s = uac2_opts->p_ot_name;
1053 	strings_fn[STR_FU_IN].s = uac2_opts->p_fu_vol_name;
1054 	strings_fn[STR_AS_IN_ALT0].s = "Capture Inactive";
1055 	strings_fn[STR_AS_IN_ALT1].s = "Capture Active";
1056 
1057 	us = usb_gstrings_attach(cdev, fn_strings, ARRAY_SIZE(strings_fn));
1058 	if (IS_ERR(us))
1059 		return PTR_ERR(us);
1060 
1061 	if (FUOUT_EN(uac2_opts)) {
1062 		out_feature_unit_desc = build_fu_desc(uac2_opts->c_chmask);
1063 		if (!out_feature_unit_desc)
1064 			return -ENOMEM;
1065 	}
1066 	if (FUIN_EN(uac2_opts)) {
1067 		in_feature_unit_desc = build_fu_desc(uac2_opts->p_chmask);
1068 		if (!in_feature_unit_desc) {
1069 			ret = -ENOMEM;
1070 			goto err_free_fu;
1071 		}
1072 	}
1073 
1074 	iad_desc.iFunction = us[STR_ASSOC].id;
1075 	std_ac_if_desc.iInterface = us[STR_IF_CTRL].id;
1076 	in_clk_src_desc.iClockSource = us[STR_CLKSRC_IN].id;
1077 	out_clk_src_desc.iClockSource = us[STR_CLKSRC_OUT].id;
1078 	usb_out_it_desc.iTerminal = us[STR_USB_IT].id;
1079 	usb_out_it_desc.iChannelNames = us[STR_USB_IT_CH].id;
1080 	io_in_it_desc.iTerminal = us[STR_IO_IT].id;
1081 	io_in_it_desc.iChannelNames = us[STR_IO_IT_CH].id;
1082 	usb_in_ot_desc.iTerminal = us[STR_USB_OT].id;
1083 	io_out_ot_desc.iTerminal = us[STR_IO_OT].id;
1084 	std_as_out_if0_desc.iInterface = us[STR_AS_OUT_ALT0].id;
1085 	std_as_out_if1_desc.iInterface = us[STR_AS_OUT_ALT1].id;
1086 	std_as_in_if0_desc.iInterface = us[STR_AS_IN_ALT0].id;
1087 	std_as_in_if1_desc.iInterface = us[STR_AS_IN_ALT1].id;
1088 
1089 	if (FUOUT_EN(uac2_opts)) {
1090 		u8 *i_feature = (u8 *)out_feature_unit_desc +
1091 				out_feature_unit_desc->bLength - 1;
1092 		*i_feature = us[STR_FU_OUT].id;
1093 	}
1094 	if (FUIN_EN(uac2_opts)) {
1095 		u8 *i_feature = (u8 *)in_feature_unit_desc +
1096 				in_feature_unit_desc->bLength - 1;
1097 		*i_feature = us[STR_FU_IN].id;
1098 	}
1099 
1100 
1101 	/* Initialize the configurable parameters */
1102 	usb_out_it_desc.bNrChannels = num_channels(uac2_opts->c_chmask);
1103 	usb_out_it_desc.bmChannelConfig = cpu_to_le32(uac2_opts->c_chmask);
1104 	io_in_it_desc.bNrChannels = num_channels(uac2_opts->p_chmask);
1105 	io_in_it_desc.bmChannelConfig = cpu_to_le32(uac2_opts->p_chmask);
1106 	as_out_hdr_desc.bNrChannels = num_channels(uac2_opts->c_chmask);
1107 	as_out_hdr_desc.bmChannelConfig = cpu_to_le32(uac2_opts->c_chmask);
1108 	as_in_hdr_desc.bNrChannels = num_channels(uac2_opts->p_chmask);
1109 	as_in_hdr_desc.bmChannelConfig = cpu_to_le32(uac2_opts->p_chmask);
1110 	as_out_fmt1_desc.bSubslotSize = uac2_opts->c_ssize;
1111 	as_out_fmt1_desc.bBitResolution = uac2_opts->c_ssize * 8;
1112 	as_in_fmt1_desc.bSubslotSize = uac2_opts->p_ssize;
1113 	as_in_fmt1_desc.bBitResolution = uac2_opts->p_ssize * 8;
1114 	if (FUOUT_EN(uac2_opts)) {
1115 		__le32 *bma = (__le32 *)&out_feature_unit_desc->bmaControls[0];
1116 		u32 control = 0;
1117 
1118 		if (uac2_opts->c_mute_present)
1119 			control |= CONTROL_RDWR << FU_MUTE_CTRL;
1120 		if (uac2_opts->c_volume_present)
1121 			control |= CONTROL_RDWR << FU_VOL_CTRL;
1122 		*bma = cpu_to_le32(control);
1123 	}
1124 	if (FUIN_EN(uac2_opts)) {
1125 		__le32 *bma = (__le32 *)&in_feature_unit_desc->bmaControls[0];
1126 		u32 control = 0;
1127 
1128 		if (uac2_opts->p_mute_present)
1129 			control |= CONTROL_RDWR << FU_MUTE_CTRL;
1130 		if (uac2_opts->p_volume_present)
1131 			control |= CONTROL_RDWR << FU_VOL_CTRL;
1132 		*bma = cpu_to_le32(control);
1133 	}
1134 
1135 	ret = usb_interface_id(cfg, fn);
1136 	if (ret < 0) {
1137 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1138 		goto err_free_fu;
1139 	}
1140 	iad_desc.bFirstInterface = ret;
1141 
1142 	std_ac_if_desc.bInterfaceNumber = ret;
1143 	uac2->ac_intf = ret;
1144 	uac2->ac_alt = 0;
1145 
1146 	if (EPOUT_EN(uac2_opts)) {
1147 		ret = usb_interface_id(cfg, fn);
1148 		if (ret < 0) {
1149 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1150 			goto err_free_fu;
1151 		}
1152 		std_as_out_if0_desc.bInterfaceNumber = ret;
1153 		std_as_out_if1_desc.bInterfaceNumber = ret;
1154 		std_as_out_if1_desc.bNumEndpoints = 1;
1155 		uac2->as_out_intf = ret;
1156 		uac2->as_out_alt = 0;
1157 
1158 		if (EPOUT_FBACK_IN_EN(uac2_opts)) {
1159 			fs_epout_desc.bmAttributes =
1160 			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC;
1161 			hs_epout_desc.bmAttributes =
1162 			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC;
1163 			ss_epout_desc.bmAttributes =
1164 			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC;
1165 			std_as_out_if1_desc.bNumEndpoints++;
1166 		} else {
1167 			fs_epout_desc.bmAttributes =
1168 			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ADAPTIVE;
1169 			hs_epout_desc.bmAttributes =
1170 			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ADAPTIVE;
1171 			ss_epout_desc.bmAttributes =
1172 			  USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ADAPTIVE;
1173 		}
1174 	}
1175 
1176 	if (EPIN_EN(uac2_opts)) {
1177 		ret = usb_interface_id(cfg, fn);
1178 		if (ret < 0) {
1179 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1180 			goto err_free_fu;
1181 		}
1182 		std_as_in_if0_desc.bInterfaceNumber = ret;
1183 		std_as_in_if1_desc.bInterfaceNumber = ret;
1184 		uac2->as_in_intf = ret;
1185 		uac2->as_in_alt = 0;
1186 	}
1187 
1188 	if (FUOUT_EN(uac2_opts) || FUIN_EN(uac2_opts)) {
1189 		uac2->int_ep = usb_ep_autoconfig(gadget, &fs_ep_int_desc);
1190 		if (!uac2->int_ep) {
1191 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1192 			ret = -ENODEV;
1193 			goto err_free_fu;
1194 		}
1195 
1196 		std_ac_if_desc.bNumEndpoints = 1;
1197 	}
1198 
1199 	hs_epin_desc.bInterval = uac2_opts->p_hs_bint;
1200 	ss_epin_desc.bInterval = uac2_opts->p_hs_bint;
1201 	hs_epout_desc.bInterval = uac2_opts->c_hs_bint;
1202 	ss_epout_desc.bInterval = uac2_opts->c_hs_bint;
1203 
1204 	/* Calculate wMaxPacketSize according to audio bandwidth */
1205 	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &fs_epin_desc,
1206 					USB_SPEED_FULL, true);
1207 	if (ret < 0) {
1208 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1209 		return ret;
1210 	}
1211 
1212 	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &fs_epout_desc,
1213 					USB_SPEED_FULL, false);
1214 	if (ret < 0) {
1215 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1216 		return ret;
1217 	}
1218 
1219 	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &hs_epin_desc,
1220 					USB_SPEED_HIGH, true);
1221 	if (ret < 0) {
1222 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1223 		return ret;
1224 	}
1225 
1226 	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &hs_epout_desc,
1227 					USB_SPEED_HIGH, false);
1228 	if (ret < 0) {
1229 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1230 		return ret;
1231 	}
1232 
1233 	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &ss_epin_desc,
1234 					USB_SPEED_SUPER, true);
1235 	if (ret < 0) {
1236 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1237 		return ret;
1238 	}
1239 
1240 	ret = set_ep_max_packet_size_bint(dev, uac2_opts, &ss_epout_desc,
1241 					USB_SPEED_SUPER, false);
1242 	if (ret < 0) {
1243 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1244 		return ret;
1245 	}
1246 
1247 	if (EPOUT_EN(uac2_opts)) {
1248 		agdev->out_ep = usb_ep_autoconfig(gadget, &fs_epout_desc);
1249 		if (!agdev->out_ep) {
1250 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1251 			ret = -ENODEV;
1252 			goto err_free_fu;
1253 		}
1254 		if (EPOUT_FBACK_IN_EN(uac2_opts)) {
1255 			agdev->in_ep_fback = usb_ep_autoconfig(gadget,
1256 						       &fs_epin_fback_desc);
1257 			if (!agdev->in_ep_fback) {
1258 				dev_err(dev, "%s:%d Error!\n",
1259 					__func__, __LINE__);
1260 				ret = -ENODEV;
1261 				goto err_free_fu;
1262 			}
1263 		}
1264 	}
1265 
1266 	if (EPIN_EN(uac2_opts)) {
1267 		agdev->in_ep = usb_ep_autoconfig(gadget, &fs_epin_desc);
1268 		if (!agdev->in_ep) {
1269 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1270 			ret = -ENODEV;
1271 			goto err_free_fu;
1272 		}
1273 	}
1274 
1275 	agdev->in_ep_maxpsize = max_t(u16,
1276 				le16_to_cpu(fs_epin_desc.wMaxPacketSize),
1277 				le16_to_cpu(hs_epin_desc.wMaxPacketSize));
1278 	agdev->out_ep_maxpsize = max_t(u16,
1279 				le16_to_cpu(fs_epout_desc.wMaxPacketSize),
1280 				le16_to_cpu(hs_epout_desc.wMaxPacketSize));
1281 
1282 	agdev->in_ep_maxpsize = max_t(u16, agdev->in_ep_maxpsize,
1283 				le16_to_cpu(ss_epin_desc.wMaxPacketSize));
1284 	agdev->out_ep_maxpsize = max_t(u16, agdev->out_ep_maxpsize,
1285 				le16_to_cpu(ss_epout_desc.wMaxPacketSize));
1286 
1287 	ss_epin_desc_comp.wBytesPerInterval = ss_epin_desc.wMaxPacketSize;
1288 	ss_epout_desc_comp.wBytesPerInterval = ss_epout_desc.wMaxPacketSize;
1289 
1290 	// HS and SS endpoint addresses are copied from autoconfigured FS descriptors
1291 	hs_ep_int_desc.bEndpointAddress = fs_ep_int_desc.bEndpointAddress;
1292 	hs_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
1293 	hs_epin_fback_desc.bEndpointAddress = fs_epin_fback_desc.bEndpointAddress;
1294 	hs_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
1295 	ss_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
1296 	ss_epin_fback_desc.bEndpointAddress = fs_epin_fback_desc.bEndpointAddress;
1297 	ss_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
1298 	ss_ep_int_desc.bEndpointAddress = fs_ep_int_desc.bEndpointAddress;
1299 
1300 	setup_descriptor(uac2_opts);
1301 
1302 	ret = usb_assign_descriptors(fn, fs_audio_desc, hs_audio_desc, ss_audio_desc,
1303 				     ss_audio_desc);
1304 	if (ret)
1305 		goto err_free_fu;
1306 
1307 	agdev->gadget = gadget;
1308 
1309 	agdev->params.p_chmask = uac2_opts->p_chmask;
1310 	memcpy(agdev->params.p_srates, uac2_opts->p_srates,
1311 			sizeof(agdev->params.p_srates));
1312 	agdev->params.p_ssize = uac2_opts->p_ssize;
1313 	if (FUIN_EN(uac2_opts)) {
1314 		agdev->params.p_fu.id = USB_IN_FU_ID;
1315 		agdev->params.p_fu.mute_present = uac2_opts->p_mute_present;
1316 		agdev->params.p_fu.volume_present = uac2_opts->p_volume_present;
1317 		agdev->params.p_fu.volume_min = uac2_opts->p_volume_min;
1318 		agdev->params.p_fu.volume_max = uac2_opts->p_volume_max;
1319 		agdev->params.p_fu.volume_res = uac2_opts->p_volume_res;
1320 	}
1321 	agdev->params.c_chmask = uac2_opts->c_chmask;
1322 	memcpy(agdev->params.c_srates, uac2_opts->c_srates,
1323 			sizeof(agdev->params.c_srates));
1324 	agdev->params.c_ssize = uac2_opts->c_ssize;
1325 	if (FUOUT_EN(uac2_opts)) {
1326 		agdev->params.c_fu.id = USB_OUT_FU_ID;
1327 		agdev->params.c_fu.mute_present = uac2_opts->c_mute_present;
1328 		agdev->params.c_fu.volume_present = uac2_opts->c_volume_present;
1329 		agdev->params.c_fu.volume_min = uac2_opts->c_volume_min;
1330 		agdev->params.c_fu.volume_max = uac2_opts->c_volume_max;
1331 		agdev->params.c_fu.volume_res = uac2_opts->c_volume_res;
1332 	}
1333 	agdev->params.req_number = uac2_opts->req_number;
1334 	agdev->params.fb_max = uac2_opts->fb_max;
1335 
1336 	if (FUOUT_EN(uac2_opts) || FUIN_EN(uac2_opts))
1337     agdev->notify = afunc_notify;
1338 
1339 	ret = g_audio_setup(agdev, "UAC2 PCM", "UAC2_Gadget");
1340 	if (ret)
1341 		goto err_free_descs;
1342 
1343 	return 0;
1344 
1345 err_free_descs:
1346 	usb_free_all_descriptors(fn);
1347 	agdev->gadget = NULL;
1348 err_free_fu:
1349 	kfree(out_feature_unit_desc);
1350 	out_feature_unit_desc = NULL;
1351 	kfree(in_feature_unit_desc);
1352 	in_feature_unit_desc = NULL;
1353 	return ret;
1354 }
1355 
1356 static void
1357 afunc_notify_complete(struct usb_ep *_ep, struct usb_request *req)
1358 {
1359 	struct g_audio *agdev = req->context;
1360 	struct f_uac2 *uac2 = func_to_uac2(&agdev->func);
1361 
1362 	atomic_dec(&uac2->int_count);
1363 	kfree(req->buf);
1364 	usb_ep_free_request(_ep, req);
1365 }
1366 
1367 static int
1368 afunc_notify(struct g_audio *agdev, int unit_id, int cs)
1369 {
1370 	struct f_uac2 *uac2 = func_to_uac2(&agdev->func);
1371 	struct usb_request *req;
1372 	struct uac2_interrupt_data_msg *msg;
1373 	u16 w_index, w_value;
1374 	int ret;
1375 
1376 	if (!uac2->int_ep->enabled)
1377 		return 0;
1378 
1379 	if (atomic_inc_return(&uac2->int_count) > UAC2_DEF_INT_REQ_NUM) {
1380 		atomic_dec(&uac2->int_count);
1381 		return 0;
1382 	}
1383 
1384 	req = usb_ep_alloc_request(uac2->int_ep, GFP_ATOMIC);
1385 	if (req == NULL) {
1386 		ret = -ENOMEM;
1387 		goto err_dec_int_count;
1388 	}
1389 
1390 	msg = kzalloc(sizeof(*msg), GFP_ATOMIC);
1391 	if (msg == NULL) {
1392 		ret = -ENOMEM;
1393 		goto err_free_request;
1394 	}
1395 
1396 	w_index = unit_id << 8 | uac2->ac_intf;
1397 	w_value = cs << 8;
1398 
1399 	msg->bInfo = 0; /* Non-vendor, interface interrupt */
1400 	msg->bAttribute = UAC2_CS_CUR;
1401 	msg->wIndex = cpu_to_le16(w_index);
1402 	msg->wValue = cpu_to_le16(w_value);
1403 
1404 	req->length = sizeof(*msg);
1405 	req->buf = msg;
1406 	req->context = agdev;
1407 	req->complete = afunc_notify_complete;
1408 
1409 	ret = usb_ep_queue(uac2->int_ep, req, GFP_ATOMIC);
1410 
1411 	if (ret)
1412 		goto err_free_msg;
1413 
1414 	return 0;
1415 
1416 err_free_msg:
1417 	kfree(msg);
1418 err_free_request:
1419 	usb_ep_free_request(uac2->int_ep, req);
1420 err_dec_int_count:
1421 	atomic_dec(&uac2->int_count);
1422 
1423 	return ret;
1424 }
1425 
1426 static int
1427 afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
1428 {
1429 	struct usb_composite_dev *cdev = fn->config->cdev;
1430 	struct f_uac2 *uac2 = func_to_uac2(fn);
1431 	struct g_audio *agdev = func_to_g_audio(fn);
1432 	struct usb_gadget *gadget = cdev->gadget;
1433 	struct device *dev = &gadget->dev;
1434 	int ret = 0;
1435 
1436 	/* No i/f has more than 2 alt settings */
1437 	if (alt > 1) {
1438 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1439 		return -EINVAL;
1440 	}
1441 
1442 	if (intf == uac2->ac_intf) {
1443 		/* Control I/f has only 1 AltSetting - 0 */
1444 		if (alt) {
1445 			dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1446 			return -EINVAL;
1447 		}
1448 
1449 		/* restart interrupt endpoint */
1450 		if (uac2->int_ep) {
1451 			usb_ep_disable(uac2->int_ep);
1452 			config_ep_by_speed(gadget, &agdev->func, uac2->int_ep);
1453 			usb_ep_enable(uac2->int_ep);
1454 		}
1455 
1456 		return 0;
1457 	}
1458 
1459 	if (intf == uac2->as_out_intf) {
1460 		uac2->as_out_alt = alt;
1461 
1462 		if (alt)
1463 			ret = u_audio_start_capture(&uac2->g_audio);
1464 		else
1465 			u_audio_stop_capture(&uac2->g_audio);
1466 	} else if (intf == uac2->as_in_intf) {
1467 		uac2->as_in_alt = alt;
1468 
1469 		if (alt)
1470 			ret = u_audio_start_playback(&uac2->g_audio);
1471 		else
1472 			u_audio_stop_playback(&uac2->g_audio);
1473 	} else {
1474 		dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
1475 		return -EINVAL;
1476 	}
1477 
1478 	return ret;
1479 }
1480 
1481 static int
1482 afunc_get_alt(struct usb_function *fn, unsigned intf)
1483 {
1484 	struct f_uac2 *uac2 = func_to_uac2(fn);
1485 	struct g_audio *agdev = func_to_g_audio(fn);
1486 
1487 	if (intf == uac2->ac_intf)
1488 		return uac2->ac_alt;
1489 	else if (intf == uac2->as_out_intf)
1490 		return uac2->as_out_alt;
1491 	else if (intf == uac2->as_in_intf)
1492 		return uac2->as_in_alt;
1493 	else
1494 		dev_err(&agdev->gadget->dev,
1495 			"%s:%d Invalid Interface %d!\n",
1496 			__func__, __LINE__, intf);
1497 
1498 	return -EINVAL;
1499 }
1500 
1501 static void
1502 afunc_disable(struct usb_function *fn)
1503 {
1504 	struct f_uac2 *uac2 = func_to_uac2(fn);
1505 
1506 	uac2->as_in_alt = 0;
1507 	uac2->as_out_alt = 0;
1508 	u_audio_stop_capture(&uac2->g_audio);
1509 	u_audio_stop_playback(&uac2->g_audio);
1510 	if (uac2->int_ep)
1511 		usb_ep_disable(uac2->int_ep);
1512 }
1513 
1514 static void
1515 afunc_suspend(struct usb_function *fn)
1516 {
1517 	struct f_uac2 *uac2 = func_to_uac2(fn);
1518 
1519 	u_audio_suspend(&uac2->g_audio);
1520 }
1521 
1522 static int
1523 in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1524 {
1525 	struct usb_request *req = fn->config->cdev->req;
1526 	struct g_audio *agdev = func_to_g_audio(fn);
1527 	struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev);
1528 	u16 w_length = le16_to_cpu(cr->wLength);
1529 	u16 w_index = le16_to_cpu(cr->wIndex);
1530 	u16 w_value = le16_to_cpu(cr->wValue);
1531 	u8 entity_id = (w_index >> 8) & 0xff;
1532 	u8 control_selector = w_value >> 8;
1533 	int value = -EOPNOTSUPP;
1534 	u32 p_srate, c_srate;
1535 
1536 	u_audio_get_playback_srate(agdev, &p_srate);
1537 	u_audio_get_capture_srate(agdev, &c_srate);
1538 
1539 	if ((entity_id == USB_IN_CLK_ID) || (entity_id == USB_OUT_CLK_ID)) {
1540 		if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
1541 			struct cntrl_cur_lay3 c;
1542 
1543 			memset(&c, 0, sizeof(struct cntrl_cur_lay3));
1544 
1545 			if (entity_id == USB_IN_CLK_ID)
1546 				c.dCUR = cpu_to_le32(p_srate);
1547 			else if (entity_id == USB_OUT_CLK_ID)
1548 				c.dCUR = cpu_to_le32(c_srate);
1549 
1550 			value = min_t(unsigned int, w_length, sizeof(c));
1551 			memcpy(req->buf, &c, value);
1552 		} else if (control_selector == UAC2_CS_CONTROL_CLOCK_VALID) {
1553 			*(u8 *)req->buf = 1;
1554 			value = min_t(unsigned int, w_length, 1);
1555 		} else {
1556 			dev_err(&agdev->gadget->dev,
1557 				"%s:%d control_selector=%d TODO!\n",
1558 				__func__, __LINE__, control_selector);
1559 		}
1560 	} else if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
1561 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
1562 		unsigned int is_playback = 0;
1563 
1564 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
1565 			is_playback = 1;
1566 
1567 		if (control_selector == UAC_FU_MUTE) {
1568 			unsigned int mute;
1569 
1570 			u_audio_get_mute(agdev, is_playback, &mute);
1571 
1572 			*(u8 *)req->buf = mute;
1573 			value = min_t(unsigned int, w_length, 1);
1574 		} else if (control_selector == UAC_FU_VOLUME) {
1575 			struct cntrl_cur_lay2 c;
1576 			s16 volume;
1577 
1578 			memset(&c, 0, sizeof(struct cntrl_cur_lay2));
1579 
1580 			u_audio_get_volume(agdev, is_playback, &volume);
1581 			c.wCUR = cpu_to_le16(volume);
1582 
1583 			value = min_t(unsigned int, w_length, sizeof(c));
1584 			memcpy(req->buf, &c, value);
1585 		} else {
1586 			dev_err(&agdev->gadget->dev,
1587 				"%s:%d control_selector=%d TODO!\n",
1588 				__func__, __LINE__, control_selector);
1589 		}
1590 	} else {
1591 		dev_err(&agdev->gadget->dev,
1592 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
1593 			__func__, __LINE__, entity_id, control_selector);
1594 	}
1595 
1596 	return value;
1597 }
1598 
1599 static int
1600 in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1601 {
1602 	struct usb_request *req = fn->config->cdev->req;
1603 	struct g_audio *agdev = func_to_g_audio(fn);
1604 	struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev);
1605 	u16 w_length = le16_to_cpu(cr->wLength);
1606 	u16 w_index = le16_to_cpu(cr->wIndex);
1607 	u16 w_value = le16_to_cpu(cr->wValue);
1608 	u8 entity_id = (w_index >> 8) & 0xff;
1609 	u8 control_selector = w_value >> 8;
1610 	int value = -EOPNOTSUPP;
1611 
1612 	if ((entity_id == USB_IN_CLK_ID) || (entity_id == USB_OUT_CLK_ID)) {
1613 		if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
1614 			struct cntrl_ranges_lay3_srates rs;
1615 			int i;
1616 			int wNumSubRanges = 0;
1617 			int srate;
1618 			int *srates;
1619 
1620 			if (entity_id == USB_IN_CLK_ID)
1621 				srates = opts->p_srates;
1622 			else if (entity_id == USB_OUT_CLK_ID)
1623 				srates = opts->c_srates;
1624 			else
1625 				return -EOPNOTSUPP;
1626 			for (i = 0; i < UAC_MAX_RATES; i++) {
1627 				srate = srates[i];
1628 				if (srate == 0)
1629 					break;
1630 
1631 				rs.r[wNumSubRanges].dMIN = cpu_to_le32(srate);
1632 				rs.r[wNumSubRanges].dMAX = cpu_to_le32(srate);
1633 				rs.r[wNumSubRanges].dRES = 0;
1634 				wNumSubRanges++;
1635 				dev_dbg(&agdev->gadget->dev,
1636 					"%s(): clk %d: rate ID %d: %d\n",
1637 					__func__, entity_id, wNumSubRanges, srate);
1638 			}
1639 			rs.wNumSubRanges = cpu_to_le16(wNumSubRanges);
1640 			value = min_t(unsigned int, w_length, ranges_lay3_size(rs));
1641 			dev_dbg(&agdev->gadget->dev, "%s(): sending %d rates, size %d\n",
1642 				__func__, rs.wNumSubRanges, value);
1643 			memcpy(req->buf, &rs, value);
1644 		} else {
1645 			dev_err(&agdev->gadget->dev,
1646 				"%s:%d control_selector=%d TODO!\n",
1647 				__func__, __LINE__, control_selector);
1648 		}
1649 	} else if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
1650 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
1651 		unsigned int is_playback = 0;
1652 
1653 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
1654 			is_playback = 1;
1655 
1656 		if (control_selector == UAC_FU_VOLUME) {
1657 			struct cntrl_range_lay2 r;
1658 			s16 max_db, min_db, res_db;
1659 
1660 			if (is_playback) {
1661 				max_db = opts->p_volume_max;
1662 				min_db = opts->p_volume_min;
1663 				res_db = opts->p_volume_res;
1664 			} else {
1665 				max_db = opts->c_volume_max;
1666 				min_db = opts->c_volume_min;
1667 				res_db = opts->c_volume_res;
1668 			}
1669 
1670 			r.wMAX = cpu_to_le16(max_db);
1671 			r.wMIN = cpu_to_le16(min_db);
1672 			r.wRES = cpu_to_le16(res_db);
1673 			r.wNumSubRanges = cpu_to_le16(1);
1674 
1675 			value = min_t(unsigned int, w_length, sizeof(r));
1676 			memcpy(req->buf, &r, value);
1677 		} else {
1678 			dev_err(&agdev->gadget->dev,
1679 				"%s:%d control_selector=%d TODO!\n",
1680 				__func__, __LINE__, control_selector);
1681 		}
1682 	} else {
1683 		dev_err(&agdev->gadget->dev,
1684 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
1685 			__func__, __LINE__, entity_id, control_selector);
1686 	}
1687 
1688 	return value;
1689 }
1690 
1691 static int
1692 ac_rq_in(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1693 {
1694 	if (cr->bRequest == UAC2_CS_CUR)
1695 		return in_rq_cur(fn, cr);
1696 	else if (cr->bRequest == UAC2_CS_RANGE)
1697 		return in_rq_range(fn, cr);
1698 	else
1699 		return -EOPNOTSUPP;
1700 }
1701 
1702 static void uac2_cs_control_sam_freq(struct usb_ep *ep, struct usb_request *req)
1703 {
1704 	struct usb_function *fn = ep->driver_data;
1705 	struct g_audio *agdev = func_to_g_audio(fn);
1706 	struct f_uac2 *uac2 = func_to_uac2(fn);
1707 	u32 val;
1708 
1709 	if (req->actual != 4)
1710 		return;
1711 
1712 	val = le32_to_cpu(*((__le32 *)req->buf));
1713 	dev_dbg(&agdev->gadget->dev, "%s val: %d.\n", __func__, val);
1714 	if (uac2->clock_id == USB_IN_CLK_ID) {
1715 		u_audio_set_playback_srate(agdev, val);
1716 	} else if (uac2->clock_id == USB_OUT_CLK_ID) {
1717 		u_audio_set_capture_srate(agdev, val);
1718 	}
1719 }
1720 
1721 static void
1722 out_rq_cur_complete(struct usb_ep *ep, struct usb_request *req)
1723 {
1724 	struct g_audio *agdev = req->context;
1725 	struct usb_composite_dev *cdev = agdev->func.config->cdev;
1726 	struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev);
1727 	struct f_uac2 *uac2 = func_to_uac2(&agdev->func);
1728 	struct usb_ctrlrequest *cr = &uac2->setup_cr;
1729 	u16 w_index = le16_to_cpu(cr->wIndex);
1730 	u16 w_value = le16_to_cpu(cr->wValue);
1731 	u8 entity_id = (w_index >> 8) & 0xff;
1732 	u8 control_selector = w_value >> 8;
1733 
1734 	if (req->status != 0) {
1735 		dev_dbg(&cdev->gadget->dev, "completion err %d\n", req->status);
1736 		return;
1737 	}
1738 
1739 	if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
1740 		(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
1741 		unsigned int is_playback = 0;
1742 
1743 		if (FUIN_EN(opts) && (entity_id == USB_IN_FU_ID))
1744 			is_playback = 1;
1745 
1746 		if (control_selector == UAC_FU_MUTE) {
1747 			u8 mute = *(u8 *)req->buf;
1748 
1749 			u_audio_set_mute(agdev, is_playback, mute);
1750 
1751 			return;
1752 		} else if (control_selector == UAC_FU_VOLUME) {
1753 			struct cntrl_cur_lay2 *c = req->buf;
1754 			s16 volume;
1755 
1756 			volume = le16_to_cpu(c->wCUR);
1757 			u_audio_set_volume(agdev, is_playback, volume);
1758 
1759 			return;
1760 		} else {
1761 			dev_err(&agdev->gadget->dev,
1762 				"%s:%d control_selector=%d TODO!\n",
1763 				__func__, __LINE__, control_selector);
1764 			usb_ep_set_halt(ep);
1765 		}
1766 	}
1767 }
1768 
1769 static int
1770 out_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1771 {
1772 	struct usb_composite_dev *cdev = fn->config->cdev;
1773 	struct usb_request *req = fn->config->cdev->req;
1774 	struct g_audio *agdev = func_to_g_audio(fn);
1775 	struct f_uac2_opts *opts = g_audio_to_uac2_opts(agdev);
1776 	struct f_uac2 *uac2 = func_to_uac2(fn);
1777 	u16 w_length = le16_to_cpu(cr->wLength);
1778 	u16 w_index = le16_to_cpu(cr->wIndex);
1779 	u16 w_value = le16_to_cpu(cr->wValue);
1780 	u8 entity_id = (w_index >> 8) & 0xff;
1781 	u8 control_selector = w_value >> 8;
1782 	u8 clock_id = w_index >> 8;
1783 
1784 	if ((entity_id == USB_IN_CLK_ID) || (entity_id == USB_OUT_CLK_ID)) {
1785 		if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
1786 			dev_dbg(&agdev->gadget->dev,
1787 				"control_selector UAC2_CS_CONTROL_SAM_FREQ, clock: %d\n", clock_id);
1788 			cdev->gadget->ep0->driver_data = fn;
1789 			uac2->clock_id = clock_id;
1790 			req->complete = uac2_cs_control_sam_freq;
1791 			return w_length;
1792 		}
1793 	} else if ((FUIN_EN(opts) && (entity_id == USB_IN_FU_ID)) ||
1794 			(FUOUT_EN(opts) && (entity_id == USB_OUT_FU_ID))) {
1795 		memcpy(&uac2->setup_cr, cr, sizeof(*cr));
1796 		req->context = agdev;
1797 		req->complete = out_rq_cur_complete;
1798 
1799 		return w_length;
1800 	} else {
1801 		dev_err(&agdev->gadget->dev,
1802 			"%s:%d entity_id=%d control_selector=%d TODO!\n",
1803 			__func__, __LINE__, entity_id, control_selector);
1804 	}
1805 	return -EOPNOTSUPP;
1806 }
1807 
1808 static int
1809 setup_rq_inf(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1810 {
1811 	struct f_uac2 *uac2 = func_to_uac2(fn);
1812 	struct g_audio *agdev = func_to_g_audio(fn);
1813 	u16 w_index = le16_to_cpu(cr->wIndex);
1814 	u8 intf = w_index & 0xff;
1815 
1816 	if (intf != uac2->ac_intf) {
1817 		dev_err(&agdev->gadget->dev,
1818 			"%s:%d Error!\n", __func__, __LINE__);
1819 		return -EOPNOTSUPP;
1820 	}
1821 
1822 	if (cr->bRequestType & USB_DIR_IN)
1823 		return ac_rq_in(fn, cr);
1824 	else if (cr->bRequest == UAC2_CS_CUR)
1825 		return out_rq_cur(fn, cr);
1826 
1827 	return -EOPNOTSUPP;
1828 }
1829 
1830 static int
1831 afunc_setup(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1832 {
1833 	struct usb_composite_dev *cdev = fn->config->cdev;
1834 	struct g_audio *agdev = func_to_g_audio(fn);
1835 	struct usb_request *req = cdev->req;
1836 	u16 w_length = le16_to_cpu(cr->wLength);
1837 	int value = -EOPNOTSUPP;
1838 
1839 	/* Only Class specific requests are supposed to reach here */
1840 	if ((cr->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
1841 		return -EOPNOTSUPP;
1842 
1843 	if ((cr->bRequestType & USB_RECIP_MASK) == USB_RECIP_INTERFACE)
1844 		value = setup_rq_inf(fn, cr);
1845 	else
1846 		dev_err(&agdev->gadget->dev, "%s:%d Error!\n",
1847 				__func__, __LINE__);
1848 
1849 	if (value >= 0) {
1850 		req->length = value;
1851 		req->zero = value < w_length;
1852 		value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1853 		if (value < 0) {
1854 			dev_err(&agdev->gadget->dev,
1855 				"%s:%d Error!\n", __func__, __LINE__);
1856 			req->status = 0;
1857 		}
1858 	}
1859 
1860 	return value;
1861 }
1862 
1863 static inline struct f_uac2_opts *to_f_uac2_opts(struct config_item *item)
1864 {
1865 	return container_of(to_config_group(item), struct f_uac2_opts,
1866 			    func_inst.group);
1867 }
1868 
1869 static void f_uac2_attr_release(struct config_item *item)
1870 {
1871 	struct f_uac2_opts *opts = to_f_uac2_opts(item);
1872 
1873 	usb_put_function_instance(&opts->func_inst);
1874 }
1875 
1876 static struct configfs_item_operations f_uac2_item_ops = {
1877 	.release	= f_uac2_attr_release,
1878 };
1879 
1880 #define uac2_kstrtou8 kstrtou8
1881 #define uac2_kstrtou32 kstrtou32
1882 #define uac2_kstrtos16 kstrtos16
1883 #define uac2_kstrtobool(s, base, res) kstrtobool((s), (res))
1884 
1885 static const char *u8_fmt = "%u\n";
1886 static const char *u32_fmt = "%u\n";
1887 static const char *s16_fmt = "%hd\n";
1888 static const char *bool_fmt = "%u\n";
1889 
1890 #define UAC2_ATTRIBUTE(type, name)					\
1891 static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
1892 					 char *page)			\
1893 {									\
1894 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
1895 	int result;							\
1896 									\
1897 	mutex_lock(&opts->lock);					\
1898 	result = sprintf(page, type##_fmt, opts->name);			\
1899 	mutex_unlock(&opts->lock);					\
1900 									\
1901 	return result;							\
1902 }									\
1903 									\
1904 static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
1905 					  const char *page, size_t len)	\
1906 {									\
1907 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
1908 	int ret;							\
1909 	type num;							\
1910 									\
1911 	mutex_lock(&opts->lock);					\
1912 	if (opts->refcnt) {						\
1913 		ret = -EBUSY;						\
1914 		goto end;						\
1915 	}								\
1916 									\
1917 	ret = uac2_kstrto##type(page, 0, &num);				\
1918 	if (ret)							\
1919 		goto end;						\
1920 									\
1921 	opts->name = num;						\
1922 	ret = len;							\
1923 									\
1924 end:									\
1925 	mutex_unlock(&opts->lock);					\
1926 	return ret;							\
1927 }									\
1928 									\
1929 CONFIGFS_ATTR(f_uac2_opts_, name)
1930 
1931 #define UAC2_ATTRIBUTE_SYNC(name)					\
1932 static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
1933 					 char *page)			\
1934 {									\
1935 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
1936 	int result;							\
1937 	char *str;							\
1938 									\
1939 	mutex_lock(&opts->lock);					\
1940 	switch (opts->name) {						\
1941 	case USB_ENDPOINT_SYNC_ASYNC:					\
1942 		str = "async";						\
1943 		break;							\
1944 	case USB_ENDPOINT_SYNC_ADAPTIVE:				\
1945 		str = "adaptive";					\
1946 		break;							\
1947 	default:							\
1948 		str = "unknown";					\
1949 		break;							\
1950 	}								\
1951 	result = sprintf(page, "%s\n", str);				\
1952 	mutex_unlock(&opts->lock);					\
1953 									\
1954 	return result;							\
1955 }									\
1956 									\
1957 static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
1958 					  const char *page, size_t len)	\
1959 {									\
1960 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
1961 	int ret = 0;							\
1962 									\
1963 	mutex_lock(&opts->lock);					\
1964 	if (opts->refcnt) {						\
1965 		ret = -EBUSY;						\
1966 		goto end;						\
1967 	}								\
1968 									\
1969 	if (!strncmp(page, "async", 5))					\
1970 		opts->name = USB_ENDPOINT_SYNC_ASYNC;			\
1971 	else if (!strncmp(page, "adaptive", 8))				\
1972 		opts->name = USB_ENDPOINT_SYNC_ADAPTIVE;		\
1973 	else {								\
1974 		ret = -EINVAL;						\
1975 		goto end;						\
1976 	}								\
1977 									\
1978 	ret = len;							\
1979 									\
1980 end:									\
1981 	mutex_unlock(&opts->lock);					\
1982 	return ret;							\
1983 }									\
1984 									\
1985 CONFIGFS_ATTR(f_uac2_opts_, name)
1986 
1987 #define UAC2_RATE_ATTRIBUTE(name)					\
1988 static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
1989 					 char *page)			\
1990 {									\
1991 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
1992 	int result = 0;							\
1993 	int i;								\
1994 									\
1995 	mutex_lock(&opts->lock);					\
1996 	page[0] = '\0';							\
1997 	for (i = 0; i < UAC_MAX_RATES; i++) {				\
1998 		if (opts->name##s[i] == 0)				\
1999 			break;						\
2000 		result += sprintf(page + strlen(page), "%u,",		\
2001 				opts->name##s[i]);			\
2002 	}								\
2003 	if (strlen(page) > 0)						\
2004 		page[strlen(page) - 1] = '\n';				\
2005 	mutex_unlock(&opts->lock);					\
2006 									\
2007 	return result;							\
2008 }									\
2009 									\
2010 static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
2011 					  const char *page, size_t len)	\
2012 {									\
2013 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
2014 	char *split_page = NULL;					\
2015 	int ret = -EINVAL;						\
2016 	char *token;							\
2017 	u32 num;							\
2018 	int i;								\
2019 									\
2020 	mutex_lock(&opts->lock);					\
2021 	if (opts->refcnt) {						\
2022 		ret = -EBUSY;						\
2023 		goto end;						\
2024 	}								\
2025 									\
2026 	i = 0;								\
2027 	memset(opts->name##s, 0x00, sizeof(opts->name##s));		\
2028 	split_page = kstrdup(page, GFP_KERNEL);				\
2029 	while ((token = strsep(&split_page, ",")) != NULL) {		\
2030 		ret = kstrtou32(token, 0, &num);			\
2031 		if (ret)						\
2032 			goto end;					\
2033 									\
2034 		opts->name##s[i++] = num;				\
2035 		ret = len;						\
2036 	};								\
2037 									\
2038 end:									\
2039 	kfree(split_page);						\
2040 	mutex_unlock(&opts->lock);					\
2041 	return ret;							\
2042 }									\
2043 									\
2044 CONFIGFS_ATTR(f_uac2_opts_, name)
2045 
2046 #define UAC2_ATTRIBUTE_STRING(name)					\
2047 static ssize_t f_uac2_opts_##name##_show(struct config_item *item,	\
2048 					 char *page)			\
2049 {									\
2050 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
2051 	int result;							\
2052 									\
2053 	mutex_lock(&opts->lock);					\
2054 	result = scnprintf(page, sizeof(opts->name), "%s", opts->name);	\
2055 	mutex_unlock(&opts->lock);					\
2056 									\
2057 	return result;							\
2058 }									\
2059 									\
2060 static ssize_t f_uac2_opts_##name##_store(struct config_item *item,	\
2061 					  const char *page, size_t len)	\
2062 {									\
2063 	struct f_uac2_opts *opts = to_f_uac2_opts(item);		\
2064 	int ret = 0;							\
2065 									\
2066 	mutex_lock(&opts->lock);					\
2067 	if (opts->refcnt) {						\
2068 		ret = -EBUSY;						\
2069 		goto end;						\
2070 	}								\
2071 									\
2072 	if (len && page[len - 1] == '\n')				\
2073 		len--;							\
2074 									\
2075 	ret = scnprintf(opts->name, min(sizeof(opts->name), len + 1),	\
2076 			"%s", page);					\
2077 									\
2078 end:									\
2079 	mutex_unlock(&opts->lock);					\
2080 	return ret;							\
2081 }									\
2082 									\
2083 CONFIGFS_ATTR(f_uac2_opts_, name)
2084 
2085 UAC2_ATTRIBUTE(u32, p_chmask);
2086 UAC2_RATE_ATTRIBUTE(p_srate);
2087 UAC2_ATTRIBUTE(u32, p_ssize);
2088 UAC2_ATTRIBUTE(u8, p_hs_bint);
2089 UAC2_ATTRIBUTE(u32, c_chmask);
2090 UAC2_RATE_ATTRIBUTE(c_srate);
2091 UAC2_ATTRIBUTE_SYNC(c_sync);
2092 UAC2_ATTRIBUTE(u32, c_ssize);
2093 UAC2_ATTRIBUTE(u8, c_hs_bint);
2094 UAC2_ATTRIBUTE(u32, req_number);
2095 
2096 UAC2_ATTRIBUTE(bool, p_mute_present);
2097 UAC2_ATTRIBUTE(bool, p_volume_present);
2098 UAC2_ATTRIBUTE(s16, p_volume_min);
2099 UAC2_ATTRIBUTE(s16, p_volume_max);
2100 UAC2_ATTRIBUTE(s16, p_volume_res);
2101 
2102 UAC2_ATTRIBUTE(bool, c_mute_present);
2103 UAC2_ATTRIBUTE(bool, c_volume_present);
2104 UAC2_ATTRIBUTE(s16, c_volume_min);
2105 UAC2_ATTRIBUTE(s16, c_volume_max);
2106 UAC2_ATTRIBUTE(s16, c_volume_res);
2107 UAC2_ATTRIBUTE(u32, fb_max);
2108 UAC2_ATTRIBUTE_STRING(function_name);
2109 UAC2_ATTRIBUTE_STRING(if_ctrl_name);
2110 UAC2_ATTRIBUTE_STRING(clksrc_in_name);
2111 UAC2_ATTRIBUTE_STRING(clksrc_out_name);
2112 
2113 UAC2_ATTRIBUTE_STRING(p_it_name);
2114 UAC2_ATTRIBUTE_STRING(p_it_ch_name);
2115 UAC2_ATTRIBUTE_STRING(p_ot_name);
2116 UAC2_ATTRIBUTE_STRING(p_fu_vol_name);
2117 
2118 UAC2_ATTRIBUTE_STRING(c_it_name);
2119 UAC2_ATTRIBUTE_STRING(c_it_ch_name);
2120 UAC2_ATTRIBUTE_STRING(c_ot_name);
2121 UAC2_ATTRIBUTE_STRING(c_fu_vol_name);
2122 
2123 UAC2_ATTRIBUTE(s16, p_terminal_type);
2124 UAC2_ATTRIBUTE(s16, c_terminal_type);
2125 
2126 
2127 static struct configfs_attribute *f_uac2_attrs[] = {
2128 	&f_uac2_opts_attr_p_chmask,
2129 	&f_uac2_opts_attr_p_srate,
2130 	&f_uac2_opts_attr_p_ssize,
2131 	&f_uac2_opts_attr_p_hs_bint,
2132 	&f_uac2_opts_attr_c_chmask,
2133 	&f_uac2_opts_attr_c_srate,
2134 	&f_uac2_opts_attr_c_ssize,
2135 	&f_uac2_opts_attr_c_hs_bint,
2136 	&f_uac2_opts_attr_c_sync,
2137 	&f_uac2_opts_attr_req_number,
2138 	&f_uac2_opts_attr_fb_max,
2139 
2140 	&f_uac2_opts_attr_p_mute_present,
2141 	&f_uac2_opts_attr_p_volume_present,
2142 	&f_uac2_opts_attr_p_volume_min,
2143 	&f_uac2_opts_attr_p_volume_max,
2144 	&f_uac2_opts_attr_p_volume_res,
2145 
2146 	&f_uac2_opts_attr_c_mute_present,
2147 	&f_uac2_opts_attr_c_volume_present,
2148 	&f_uac2_opts_attr_c_volume_min,
2149 	&f_uac2_opts_attr_c_volume_max,
2150 	&f_uac2_opts_attr_c_volume_res,
2151 
2152 	&f_uac2_opts_attr_function_name,
2153 	&f_uac2_opts_attr_if_ctrl_name,
2154 	&f_uac2_opts_attr_clksrc_in_name,
2155 	&f_uac2_opts_attr_clksrc_out_name,
2156 
2157 	&f_uac2_opts_attr_p_it_name,
2158 	&f_uac2_opts_attr_p_it_ch_name,
2159 	&f_uac2_opts_attr_p_ot_name,
2160 	&f_uac2_opts_attr_p_fu_vol_name,
2161 
2162 	&f_uac2_opts_attr_c_it_name,
2163 	&f_uac2_opts_attr_c_it_ch_name,
2164 	&f_uac2_opts_attr_c_ot_name,
2165 	&f_uac2_opts_attr_c_fu_vol_name,
2166 
2167 	&f_uac2_opts_attr_p_terminal_type,
2168 	&f_uac2_opts_attr_c_terminal_type,
2169 
2170 	NULL,
2171 };
2172 
2173 static const struct config_item_type f_uac2_func_type = {
2174 	.ct_item_ops	= &f_uac2_item_ops,
2175 	.ct_attrs	= f_uac2_attrs,
2176 	.ct_owner	= THIS_MODULE,
2177 };
2178 
2179 static void afunc_free_inst(struct usb_function_instance *f)
2180 {
2181 	struct f_uac2_opts *opts;
2182 
2183 	opts = container_of(f, struct f_uac2_opts, func_inst);
2184 	kfree(opts);
2185 }
2186 
2187 static struct usb_function_instance *afunc_alloc_inst(void)
2188 {
2189 	struct f_uac2_opts *opts;
2190 
2191 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2192 	if (!opts)
2193 		return ERR_PTR(-ENOMEM);
2194 
2195 	mutex_init(&opts->lock);
2196 	opts->func_inst.free_func_inst = afunc_free_inst;
2197 
2198 	config_group_init_type_name(&opts->func_inst.group, "",
2199 				    &f_uac2_func_type);
2200 
2201 	opts->p_chmask = UAC2_DEF_PCHMASK;
2202 	opts->p_srates[0] = UAC2_DEF_PSRATE;
2203 	opts->p_ssize = UAC2_DEF_PSSIZE;
2204 	opts->p_hs_bint = UAC2_DEF_PHSBINT;
2205 	opts->c_chmask = UAC2_DEF_CCHMASK;
2206 	opts->c_srates[0] = UAC2_DEF_CSRATE;
2207 	opts->c_ssize = UAC2_DEF_CSSIZE;
2208 	opts->c_hs_bint = UAC2_DEF_CHSBINT;
2209 	opts->c_sync = UAC2_DEF_CSYNC;
2210 
2211 	opts->p_mute_present = UAC2_DEF_MUTE_PRESENT;
2212 	opts->p_volume_present = UAC2_DEF_VOLUME_PRESENT;
2213 	opts->p_volume_min = UAC2_DEF_MIN_DB;
2214 	opts->p_volume_max = UAC2_DEF_MAX_DB;
2215 	opts->p_volume_res = UAC2_DEF_RES_DB;
2216 
2217 	opts->c_mute_present = UAC2_DEF_MUTE_PRESENT;
2218 	opts->c_volume_present = UAC2_DEF_VOLUME_PRESENT;
2219 	opts->c_volume_min = UAC2_DEF_MIN_DB;
2220 	opts->c_volume_max = UAC2_DEF_MAX_DB;
2221 	opts->c_volume_res = UAC2_DEF_RES_DB;
2222 
2223 	opts->req_number = UAC2_DEF_REQ_NUM;
2224 	opts->fb_max = FBACK_FAST_MAX;
2225 
2226 	scnprintf(opts->function_name, sizeof(opts->function_name), "Source/Sink");
2227 	scnprintf(opts->if_ctrl_name, sizeof(opts->if_ctrl_name), "Topology Control");
2228 	scnprintf(opts->clksrc_in_name, sizeof(opts->clksrc_in_name), "Input Clock");
2229 	scnprintf(opts->clksrc_out_name, sizeof(opts->clksrc_out_name), "Output Clock");
2230 
2231 	scnprintf(opts->p_it_name, sizeof(opts->p_it_name), "USBD Out");
2232 	scnprintf(opts->p_it_ch_name, sizeof(opts->p_it_ch_name), "Capture Channels");
2233 	scnprintf(opts->p_ot_name, sizeof(opts->p_ot_name), "USBH In");
2234 	scnprintf(opts->p_fu_vol_name, sizeof(opts->p_fu_vol_name), "Capture Volume");
2235 
2236 	scnprintf(opts->c_it_name, sizeof(opts->c_it_name), "USBH Out");
2237 	scnprintf(opts->c_it_ch_name, sizeof(opts->c_it_ch_name), "Playback Channels");
2238 	scnprintf(opts->c_ot_name, sizeof(opts->c_ot_name), "USBD In");
2239 	scnprintf(opts->c_fu_vol_name, sizeof(opts->c_fu_vol_name), "Playback Volume");
2240 
2241 	opts->p_terminal_type = UAC2_DEF_P_TERM_TYPE;
2242 	opts->c_terminal_type = UAC2_DEF_C_TERM_TYPE;
2243 
2244 	return &opts->func_inst;
2245 }
2246 
2247 static void afunc_free(struct usb_function *f)
2248 {
2249 	struct g_audio *agdev;
2250 	struct f_uac2_opts *opts;
2251 
2252 	agdev = func_to_g_audio(f);
2253 	opts = container_of(f->fi, struct f_uac2_opts, func_inst);
2254 	kfree(agdev);
2255 	mutex_lock(&opts->lock);
2256 	--opts->refcnt;
2257 	mutex_unlock(&opts->lock);
2258 }
2259 
2260 static void afunc_unbind(struct usb_configuration *c, struct usb_function *f)
2261 {
2262 	struct g_audio *agdev = func_to_g_audio(f);
2263 
2264 	g_audio_cleanup(agdev);
2265 	usb_free_all_descriptors(f);
2266 
2267 	agdev->gadget = NULL;
2268 
2269 	kfree(out_feature_unit_desc);
2270 	out_feature_unit_desc = NULL;
2271 	kfree(in_feature_unit_desc);
2272 	in_feature_unit_desc = NULL;
2273 }
2274 
2275 static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
2276 {
2277 	struct f_uac2	*uac2;
2278 	struct f_uac2_opts *opts;
2279 
2280 	uac2 = kzalloc(sizeof(*uac2), GFP_KERNEL);
2281 	if (uac2 == NULL)
2282 		return ERR_PTR(-ENOMEM);
2283 
2284 	opts = container_of(fi, struct f_uac2_opts, func_inst);
2285 	mutex_lock(&opts->lock);
2286 	++opts->refcnt;
2287 	mutex_unlock(&opts->lock);
2288 
2289 	uac2->g_audio.func.name = "uac2_func";
2290 	uac2->g_audio.func.bind = afunc_bind;
2291 	uac2->g_audio.func.unbind = afunc_unbind;
2292 	uac2->g_audio.func.set_alt = afunc_set_alt;
2293 	uac2->g_audio.func.get_alt = afunc_get_alt;
2294 	uac2->g_audio.func.disable = afunc_disable;
2295 	uac2->g_audio.func.suspend = afunc_suspend;
2296 	uac2->g_audio.func.setup = afunc_setup;
2297 	uac2->g_audio.func.free_func = afunc_free;
2298 
2299 	return &uac2->g_audio.func;
2300 }
2301 
2302 DECLARE_USB_FUNCTION_INIT(uac2, afunc_alloc_inst, afunc_alloc);
2303 MODULE_DESCRIPTION("USB Audio Class 2.0 Function");
2304 MODULE_LICENSE("GPL");
2305 MODULE_AUTHOR("Yadwinder Singh");
2306 MODULE_AUTHOR("Jaswinder Singh");
2307 MODULE_AUTHOR("Ruslan Bilovol");
2308