xref: /linux/drivers/usb/gadget/function/f_midi2.c (revision 2eff01ee2881becc9daaa0d53477ec202136b1f4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * f_midi2.c -- USB MIDI 2.0 class function driver
4  */
5 
6 #include <linux/device.h>
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/slab.h>
10 
11 #include <sound/core.h>
12 #include <sound/control.h>
13 #include <sound/ump.h>
14 #include <sound/ump_msg.h>
15 #include <sound/ump_convert.h>
16 
17 #include <linux/usb/ch9.h>
18 #include <linux/usb/func_utils.h>
19 #include <linux/usb/gadget.h>
20 #include <linux/usb/audio.h>
21 #include <linux/usb/midi-v2.h>
22 
23 #include "u_midi2.h"
24 
25 struct f_midi2;
26 struct f_midi2_ep;
27 struct f_midi2_usb_ep;
28 
29 /* Context for each USB request */
30 struct f_midi2_req_ctx {
31 	struct f_midi2_usb_ep *usb_ep;	/* belonging USB EP */
32 	unsigned int index;		/* array index: 0-31 */
33 	struct usb_request *req;	/* assigned request */
34 };
35 
36 /* Resources for a USB Endpoint */
37 struct f_midi2_usb_ep {
38 	struct f_midi2 *card;		/* belonging card */
39 	struct f_midi2_ep *ep;		/* belonging UMP EP (optional) */
40 	struct usb_ep *usb_ep;		/* assigned USB EP */
41 	void (*complete)(struct usb_ep *usb_ep, struct usb_request *req);
42 	unsigned long free_reqs;	/* bitmap for unused requests */
43 	unsigned int num_reqs;		/* number of allocated requests */
44 	struct f_midi2_req_ctx *reqs;	/* request context array */
45 };
46 
47 /* Resources for UMP Function Block (and USB Group Terminal Block) */
48 struct f_midi2_block {
49 	struct f_midi2_block_info info;	/* FB info, copied from configfs */
50 	struct snd_ump_block *fb;	/* assigned FB */
51 	unsigned int gtb_id;		/* assigned GTB id */
52 	unsigned int string_id;		/* assigned string id */
53 };
54 
55 /* Temporary buffer for altset 0 MIDI 1.0 handling */
56 struct f_midi2_midi1_port {
57 	unsigned int pending; /* pending bytes on the input buffer */
58 	u8 buf[32];	/* raw MIDI 1.0 byte input */
59 	u8 state;	/* running status */
60 	u8 data[2];	/* rendered USB MIDI 1.0 packet data */
61 };
62 
63 /* MIDI 1.0 message states */
64 enum {
65 	STATE_INITIAL = 0,	/* pseudo state */
66 	STATE_1PARAM,
67 	STATE_2PARAM_1,
68 	STATE_2PARAM_2,
69 	STATE_SYSEX_0,
70 	STATE_SYSEX_1,
71 	STATE_SYSEX_2,
72 	STATE_REAL_TIME,
73 	STATE_FINISHED,		/* pseudo state */
74 };
75 
76 /* Resources for UMP Endpoint */
77 struct f_midi2_ep {
78 	struct snd_ump_endpoint *ump;	/* assigned UMP EP */
79 	struct f_midi2 *card;		/* belonging MIDI 2.0 device */
80 
81 	struct f_midi2_ep_info info;	/* UMP EP info, copied from configfs */
82 	unsigned int num_blks;		/* number of FBs */
83 	struct f_midi2_block blks[SNDRV_UMP_MAX_BLOCKS];	/* UMP FBs */
84 
85 	struct f_midi2_usb_ep ep_in;	/* USB MIDI EP-in */
86 	struct f_midi2_usb_ep ep_out;	/* USB MIDI EP-out */
87 
88 	u8 in_group_to_cable[SNDRV_UMP_MAX_GROUPS]; /* map to cable; 1-based! */
89 };
90 
91 /* indices for USB strings */
92 enum {
93 	STR_IFACE = 0,
94 	STR_GTB1 = 1,
95 };
96 
97 /* 1-based GTB id to string id */
98 #define gtb_to_str_id(id)	(STR_GTB1 + (id) - 1)
99 
100 /* mapping from MIDI 1.0 cable to UMP group */
101 struct midi1_cable_mapping {
102 	struct f_midi2_ep *ep;
103 	unsigned char block;
104 	unsigned char group;
105 };
106 
107 /* operation mode */
108 enum {
109 	MIDI_OP_MODE_UNSET,	/* no altset set yet */
110 	MIDI_OP_MODE_MIDI1,	/* MIDI 1.0 (altset 0) is used */
111 	MIDI_OP_MODE_MIDI2,	/* MIDI 2.0 (altset 1) is used */
112 };
113 
114 /* Resources for MIDI 2.0 Device */
115 struct f_midi2 {
116 	struct usb_function func;
117 	struct usb_gadget *gadget;
118 	struct snd_card *card;
119 
120 	/* MIDI 1.0 in/out USB EPs */
121 	struct f_midi2_usb_ep midi1_ep_in;
122 	struct f_midi2_usb_ep midi1_ep_out;
123 
124 	/* number of MIDI 1.0 I/O cables */
125 	unsigned int num_midi1_in;
126 	unsigned int num_midi1_out;
127 
128 	/* conversion for MIDI 1.0 EP-in */
129 	struct f_midi2_midi1_port midi1_port[MAX_CABLES];
130 	/* conversion for MIDI 1.0 EP-out */
131 	struct ump_cvt_to_ump midi1_ump_cvt;
132 	/* mapping between cables and UMP groups */
133 	struct midi1_cable_mapping in_cable_mapping[MAX_CABLES];
134 	struct midi1_cable_mapping out_cable_mapping[MAX_CABLES];
135 
136 	int midi_if;			/* USB MIDI interface number */
137 	int operation_mode;		/* current operation mode */
138 
139 	spinlock_t queue_lock;
140 
141 	struct f_midi2_card_info info;	/* card info, copied from configfs */
142 
143 	unsigned int num_eps;
144 	struct f_midi2_ep midi2_eps[MAX_UMP_EPS];
145 
146 	unsigned int total_blocks;	/* total number of blocks of all EPs */
147 	struct usb_string *string_defs;
148 	struct usb_string *strings;
149 };
150 
151 #define func_to_midi2(f)	container_of(f, struct f_midi2, func)
152 
153 /* convert from MIDI protocol number (1 or 2) to SNDRV_UMP_EP_INFO_PROTO_* */
154 #define to_ump_protocol(v)	(((v) & 3) << 8)
155 
156 /* get EP name string */
157 static const char *ump_ep_name(const struct f_midi2_ep *ep)
158 {
159 	return ep->info.ep_name ? ep->info.ep_name : "MIDI 2.0 Gadget";
160 }
161 
162 /* get EP product ID string */
163 static const char *ump_product_id(const struct f_midi2_ep *ep)
164 {
165 	return ep->info.product_id ? ep->info.product_id : "Unique Product ID";
166 }
167 
168 /* get FB name string */
169 static const char *ump_fb_name(const struct f_midi2_block_info *info)
170 {
171 	return info->name ? info->name : "MIDI 2.0 Gadget I/O";
172 }
173 
174 /*
175  * USB Descriptor Definitions
176  */
177 /* GTB header descriptor */
178 static struct usb_ms20_gr_trm_block_header_descriptor gtb_header_desc = {
179 	.bLength =		sizeof(gtb_header_desc),
180 	.bDescriptorType =	USB_DT_CS_GR_TRM_BLOCK,
181 	.bDescriptorSubtype =	USB_MS_GR_TRM_BLOCK_HEADER,
182 	.wTotalLength =		__cpu_to_le16(0x12), // to be filled
183 };
184 
185 /* GTB descriptor template: most items are replaced dynamically */
186 static struct usb_ms20_gr_trm_block_descriptor gtb_desc = {
187 	.bLength =		sizeof(gtb_desc),
188 	.bDescriptorType =	USB_DT_CS_GR_TRM_BLOCK,
189 	.bDescriptorSubtype =	USB_MS_GR_TRM_BLOCK,
190 	.bGrpTrmBlkID =		0x01,
191 	.bGrpTrmBlkType =	USB_MS_GR_TRM_BLOCK_TYPE_BIDIRECTIONAL,
192 	.nGroupTrm =		0x00,
193 	.nNumGroupTrm =		1,
194 	.iBlockItem =		0,
195 	.bMIDIProtocol =	USB_MS_MIDI_PROTO_1_0_64,
196 	.wMaxInputBandwidth =	0,
197 	.wMaxOutputBandwidth =	0,
198 };
199 
200 DECLARE_USB_MIDI_OUT_JACK_DESCRIPTOR(1);
201 DECLARE_USB_MS_ENDPOINT_DESCRIPTOR(16);
202 DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
203 DECLARE_USB_MS20_ENDPOINT_DESCRIPTOR(32);
204 
205 #define EP_MAX_PACKET_INT	8
206 
207 /* Audio Control Interface */
208 static struct usb_interface_descriptor midi2_audio_if_desc = {
209 	.bLength =		USB_DT_INTERFACE_SIZE,
210 	.bDescriptorType =	USB_DT_INTERFACE,
211 	.bInterfaceNumber =	0, // to be filled
212 	.bNumEndpoints =	0,
213 	.bInterfaceClass =	USB_CLASS_AUDIO,
214 	.bInterfaceSubClass =	USB_SUBCLASS_AUDIOCONTROL,
215 	.bInterfaceProtocol =	0,
216 	.iInterface =		0,
217 };
218 
219 static struct uac1_ac_header_descriptor_1 midi2_audio_class_desc = {
220 	.bLength =		0x09,
221 	.bDescriptorType =	USB_DT_CS_INTERFACE,
222 	.bDescriptorSubtype =	0x01,
223 	.bcdADC =		__cpu_to_le16(0x0100),
224 	.wTotalLength =		__cpu_to_le16(0x0009),
225 	.bInCollection =	0x01,
226 	.baInterfaceNr =	{ 0x01 }, // to be filled
227 };
228 
229 /* MIDI 1.0 Streaming Interface (altset 0) */
230 static struct usb_interface_descriptor midi2_midi1_if_desc = {
231 	.bLength =		USB_DT_INTERFACE_SIZE,
232 	.bDescriptorType =	USB_DT_INTERFACE,
233 	.bInterfaceNumber =	0, // to be filled
234 	.bAlternateSetting =	0,
235 	.bNumEndpoints =	2, // to be filled
236 	.bInterfaceClass =	USB_CLASS_AUDIO,
237 	.bInterfaceSubClass =	USB_SUBCLASS_MIDISTREAMING,
238 	.bInterfaceProtocol =	0,
239 	.iInterface =		0, // to be filled
240 };
241 
242 static struct usb_ms_header_descriptor midi2_midi1_class_desc = {
243 	.bLength =		0x07,
244 	.bDescriptorType =	USB_DT_CS_INTERFACE,
245 	.bDescriptorSubtype =	USB_MS_HEADER,
246 	.bcdMSC =		__cpu_to_le16(0x0100),
247 	.wTotalLength =		__cpu_to_le16(0x41), // to be calculated
248 };
249 
250 /* MIDI 1.0 EP OUT */
251 static struct usb_endpoint_descriptor midi2_midi1_ep_out_desc = {
252 	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
253 	.bDescriptorType =	USB_DT_ENDPOINT,
254 	.bEndpointAddress =	USB_DIR_OUT | 0, // set up dynamically
255 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
256 };
257 
258 static struct usb_ss_ep_comp_descriptor midi2_midi1_ep_out_ss_comp_desc = {
259 	.bLength                = sizeof(midi2_midi1_ep_out_ss_comp_desc),
260 	.bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
261 };
262 
263 static struct usb_ms_endpoint_descriptor_16 midi2_midi1_ep_out_class_desc = {
264 	.bLength =		0x05, // to be filled
265 	.bDescriptorType =	USB_DT_CS_ENDPOINT,
266 	.bDescriptorSubtype =	USB_MS_GENERAL,
267 	.bNumEmbMIDIJack =	1,
268 	.baAssocJackID =	{ 0x01 },
269 };
270 
271 /* MIDI 1.0 EP IN */
272 static struct usb_endpoint_descriptor midi2_midi1_ep_in_desc = {
273 	.bLength =		USB_DT_ENDPOINT_AUDIO_SIZE,
274 	.bDescriptorType =	USB_DT_ENDPOINT,
275 	.bEndpointAddress =	USB_DIR_IN | 0, // set up dynamically
276 	.bmAttributes =		USB_ENDPOINT_XFER_BULK,
277 };
278 
279 static struct usb_ss_ep_comp_descriptor midi2_midi1_ep_in_ss_comp_desc = {
280 	.bLength                = sizeof(midi2_midi1_ep_in_ss_comp_desc),
281 	.bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
282 };
283 
284 static struct usb_ms_endpoint_descriptor_16 midi2_midi1_ep_in_class_desc = {
285 	.bLength =		0x05, // to be filled
286 	.bDescriptorType =	USB_DT_CS_ENDPOINT,
287 	.bDescriptorSubtype =	USB_MS_GENERAL,
288 	.bNumEmbMIDIJack =	1,
289 	.baAssocJackID =	{ 0x03 },
290 };
291 
292 /* MIDI 2.0 Streaming Interface (altset 1) */
293 static struct usb_interface_descriptor midi2_midi2_if_desc = {
294 	.bLength =		USB_DT_INTERFACE_SIZE,
295 	.bDescriptorType =	USB_DT_INTERFACE,
296 	.bInterfaceNumber =	0, // to be filled
297 	.bAlternateSetting =	1,
298 	.bNumEndpoints =	2, // to be filled
299 	.bInterfaceClass =	USB_CLASS_AUDIO,
300 	.bInterfaceSubClass =	USB_SUBCLASS_MIDISTREAMING,
301 	.bInterfaceProtocol =	0,
302 	.iInterface =		0, // to be filled
303 };
304 
305 static struct usb_ms_header_descriptor midi2_midi2_class_desc = {
306 	.bLength =		0x07,
307 	.bDescriptorType =	USB_DT_CS_INTERFACE,
308 	.bDescriptorSubtype =	USB_MS_HEADER,
309 	.bcdMSC =		__cpu_to_le16(0x0200),
310 	.wTotalLength =		__cpu_to_le16(0x07),
311 };
312 
313 /* MIDI 2.0 EP OUT */
314 static struct usb_endpoint_descriptor midi2_midi2_ep_out_desc[MAX_UMP_EPS];
315 
316 static struct usb_ss_ep_comp_descriptor midi2_midi2_ep_out_ss_comp_desc = {
317 	.bLength                = sizeof(midi2_midi1_ep_out_ss_comp_desc),
318 	.bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
319 };
320 
321 static struct usb_ms20_endpoint_descriptor_32 midi2_midi2_ep_out_class_desc[MAX_UMP_EPS];
322 
323 /* MIDI 2.0 EP IN */
324 static struct usb_endpoint_descriptor midi2_midi2_ep_in_desc[MAX_UMP_EPS];
325 
326 static struct usb_ss_ep_comp_descriptor midi2_midi2_ep_in_ss_comp_desc = {
327 	.bLength                = sizeof(midi2_midi2_ep_in_ss_comp_desc),
328 	.bDescriptorType        = USB_DT_SS_ENDPOINT_COMP,
329 };
330 
331 static struct usb_ms20_endpoint_descriptor_32 midi2_midi2_ep_in_class_desc[MAX_UMP_EPS];
332 
333 /* Arrays of descriptors to be created */
334 static void *midi2_audio_descs[] = {
335 	&midi2_audio_if_desc,
336 	&midi2_audio_class_desc,
337 	NULL
338 };
339 
340 static void *midi2_midi1_descs[] = {
341 	&midi2_midi1_if_desc,
342 	&midi2_midi1_class_desc,
343 	NULL
344 };
345 
346 static void *midi2_midi1_ep_out_descs[] = {
347 	&midi2_midi1_ep_out_desc,
348 	&midi2_midi1_ep_out_class_desc,
349 	NULL
350 };
351 
352 static void *midi2_midi1_ep_in_descs[] = {
353 	&midi2_midi1_ep_in_desc,
354 	&midi2_midi1_ep_in_class_desc,
355 	NULL
356 };
357 
358 static void *midi2_midi1_ep_out_ss_descs[] = {
359 	&midi2_midi1_ep_out_desc,
360 	&midi2_midi1_ep_out_ss_comp_desc,
361 	&midi2_midi1_ep_out_class_desc,
362 	NULL
363 };
364 
365 static void *midi2_midi1_ep_in_ss_descs[] = {
366 	&midi2_midi1_ep_in_desc,
367 	&midi2_midi1_ep_in_ss_comp_desc,
368 	&midi2_midi1_ep_in_class_desc,
369 	NULL
370 };
371 
372 static void *midi2_midi2_descs[] = {
373 	&midi2_midi2_if_desc,
374 	&midi2_midi2_class_desc,
375 	NULL
376 };
377 
378 /*
379  * USB request handling
380  */
381 
382 /* get an empty request for the given EP */
383 static struct usb_request *get_empty_request(struct f_midi2_usb_ep *usb_ep)
384 {
385 	struct usb_request *req = NULL;
386 	unsigned long flags;
387 	int index;
388 
389 	spin_lock_irqsave(&usb_ep->card->queue_lock, flags);
390 	if (!usb_ep->free_reqs)
391 		goto unlock;
392 	index = find_first_bit(&usb_ep->free_reqs, usb_ep->num_reqs);
393 	if (index >= usb_ep->num_reqs)
394 		goto unlock;
395 	req = usb_ep->reqs[index].req;
396 	if (!req)
397 		goto unlock;
398 	clear_bit(index, &usb_ep->free_reqs);
399 	req->length = 0;
400  unlock:
401 	spin_unlock_irqrestore(&usb_ep->card->queue_lock, flags);
402 	return req;
403 }
404 
405 /* put the empty request back */
406 static void put_empty_request(struct usb_request *req)
407 {
408 	struct f_midi2_req_ctx *ctx = req->context;
409 	unsigned long flags;
410 
411 	spin_lock_irqsave(&ctx->usb_ep->card->queue_lock, flags);
412 	set_bit(ctx->index, &ctx->usb_ep->free_reqs);
413 	spin_unlock_irqrestore(&ctx->usb_ep->card->queue_lock, flags);
414 }
415 
416 /*
417  * UMP v1.1 Stream message handling
418  */
419 
420 /* queue a request to UMP EP; request is either queued or freed after this */
421 static int queue_request_ep_raw(struct usb_request *req)
422 {
423 	struct f_midi2_req_ctx *ctx = req->context;
424 	int err;
425 
426 	req->complete = ctx->usb_ep->complete;
427 	err = usb_ep_queue(ctx->usb_ep->usb_ep, req, GFP_ATOMIC);
428 	if (err) {
429 		put_empty_request(req);
430 		return err;
431 	}
432 	return 0;
433 }
434 
435 /* queue a request with endianness conversion */
436 static int queue_request_ep_in(struct usb_request *req)
437 {
438 	/* UMP packets have to be converted to little-endian */
439 	cpu_to_le32_array((u32 *)req->buf, req->length >> 2);
440 	return queue_request_ep_raw(req);
441 }
442 
443 /* reply a UMP packet via EP-in */
444 static int reply_ep_in(struct f_midi2_ep *ep, const void *buf, int len)
445 {
446 	struct f_midi2_usb_ep *usb_ep = &ep->ep_in;
447 	struct usb_request *req;
448 
449 	req = get_empty_request(usb_ep);
450 	if (!req)
451 		return -ENOSPC;
452 
453 	req->length = len;
454 	memcpy(req->buf, buf, len);
455 	return queue_request_ep_in(req);
456 }
457 
458 /* reply a UMP stream EP info */
459 static void reply_ump_stream_ep_info(struct f_midi2_ep *ep)
460 {
461 	struct snd_ump_stream_msg_ep_info rep = {
462 		.type = UMP_MSG_TYPE_STREAM,
463 		.status = UMP_STREAM_MSG_STATUS_EP_INFO,
464 		.ump_version_major = 0x01,
465 		.ump_version_minor = 0x01,
466 		.num_function_blocks = ep->num_blks,
467 		.static_function_block = !!ep->card->info.static_block,
468 		.protocol = (UMP_STREAM_MSG_EP_INFO_CAP_MIDI1 |
469 			     UMP_STREAM_MSG_EP_INFO_CAP_MIDI2) >> 8,
470 	};
471 
472 	reply_ep_in(ep, &rep, sizeof(rep));
473 }
474 
475 /* reply a UMP EP device info */
476 static void reply_ump_stream_ep_device(struct f_midi2_ep *ep)
477 {
478 	struct snd_ump_stream_msg_devince_info rep = {
479 		.type = UMP_MSG_TYPE_STREAM,
480 		.status = UMP_STREAM_MSG_STATUS_DEVICE_INFO,
481 		.manufacture_id = ep->info.manufacturer,
482 		.family_lsb = ep->info.family & 0xff,
483 		.family_msb = (ep->info.family >> 8) & 0xff,
484 		.model_lsb = ep->info.model & 0xff,
485 		.model_msb = (ep->info.model >> 8) & 0xff,
486 		.sw_revision = ep->info.sw_revision,
487 	};
488 
489 	reply_ep_in(ep, &rep, sizeof(rep));
490 }
491 
492 #define UMP_STREAM_PKT_BYTES	16	/* UMP stream packet size = 16 bytes*/
493 #define UMP_STREAM_EP_STR_OFF	2	/* offset of name string for EP info */
494 #define UMP_STREAM_FB_STR_OFF	3	/* offset of name string for FB info */
495 
496 /* Helper to replay a string */
497 static void reply_ump_stream_string(struct f_midi2_ep *ep, const u8 *name,
498 				    unsigned int type, unsigned int extra,
499 				    unsigned int start_ofs)
500 {
501 	struct f_midi2_usb_ep *usb_ep = &ep->ep_in;
502 	struct f_midi2 *midi2 = ep->card;
503 	struct usb_request *req;
504 	unsigned int pos;
505 	u32 *buf;
506 
507 	if (!*name)
508 		return;
509 	req = get_empty_request(usb_ep);
510 	if (!req)
511 		return;
512 
513 	buf = (u32 *)req->buf;
514 	pos = start_ofs;
515 	for (;;) {
516 		if (pos == start_ofs) {
517 			memset(buf, 0, UMP_STREAM_PKT_BYTES);
518 			buf[0] = ump_stream_compose(type, 0) | extra;
519 		}
520 		buf[pos / 4] |= *name++ << ((3 - (pos % 4)) * 8);
521 		if (!*name) {
522 			if (req->length)
523 				buf[0] |= UMP_STREAM_MSG_FORMAT_END << 26;
524 			req->length += UMP_STREAM_PKT_BYTES;
525 			break;
526 		}
527 		if (++pos == UMP_STREAM_PKT_BYTES) {
528 			if (!req->length)
529 				buf[0] |= UMP_STREAM_MSG_FORMAT_START << 26;
530 			else
531 				buf[0] |= UMP_STREAM_MSG_FORMAT_CONTINUE << 26;
532 			req->length += UMP_STREAM_PKT_BYTES;
533 			if (midi2->info.req_buf_size - req->length < UMP_STREAM_PKT_BYTES)
534 				break;
535 			buf += 4;
536 			pos = start_ofs;
537 		}
538 	}
539 
540 	if (req->length)
541 		queue_request_ep_in(req);
542 	else
543 		put_empty_request(req);
544 }
545 
546 /* Reply a UMP EP name string */
547 static void reply_ump_stream_ep_name(struct f_midi2_ep *ep)
548 {
549 	reply_ump_stream_string(ep, ump_ep_name(ep),
550 				UMP_STREAM_MSG_STATUS_EP_NAME, 0,
551 				UMP_STREAM_EP_STR_OFF);
552 }
553 
554 /* Reply a UMP EP product ID string */
555 static void reply_ump_stream_ep_pid(struct f_midi2_ep *ep)
556 {
557 	reply_ump_stream_string(ep, ump_product_id(ep),
558 				UMP_STREAM_MSG_STATUS_PRODUCT_ID, 0,
559 				UMP_STREAM_EP_STR_OFF);
560 }
561 
562 /* Reply a UMP EP stream config */
563 static void reply_ump_stream_ep_config(struct f_midi2_ep *ep)
564 {
565 	struct snd_ump_stream_msg_stream_cfg rep = {
566 		.type = UMP_MSG_TYPE_STREAM,
567 		.status = UMP_STREAM_MSG_STATUS_STREAM_CFG,
568 	};
569 
570 	if (ep->info.protocol == 2)
571 		rep.protocol = UMP_STREAM_MSG_EP_INFO_CAP_MIDI2 >> 8;
572 	else
573 		rep.protocol = UMP_STREAM_MSG_EP_INFO_CAP_MIDI1 >> 8;
574 
575 	reply_ep_in(ep, &rep, sizeof(rep));
576 }
577 
578 /* Reply a UMP FB info */
579 static void reply_ump_stream_fb_info(struct f_midi2_ep *ep, int blk)
580 {
581 	struct f_midi2_block_info *b = &ep->blks[blk].info;
582 	struct snd_ump_stream_msg_fb_info rep = {
583 		.type = UMP_MSG_TYPE_STREAM,
584 		.status = UMP_STREAM_MSG_STATUS_FB_INFO,
585 		.active = !!b->active,
586 		.function_block_id = blk,
587 		.ui_hint = b->ui_hint,
588 		.midi_10 = b->is_midi1,
589 		.direction = b->direction,
590 		.first_group = b->first_group,
591 		.num_groups = b->num_groups,
592 		.midi_ci_version = b->midi_ci_version,
593 		.sysex8_streams = b->sysex8_streams,
594 	};
595 
596 	reply_ep_in(ep, &rep, sizeof(rep));
597 }
598 
599 /* Reply a FB name string */
600 static void reply_ump_stream_fb_name(struct f_midi2_ep *ep, unsigned int blk)
601 {
602 	reply_ump_stream_string(ep, ump_fb_name(&ep->blks[blk].info),
603 				UMP_STREAM_MSG_STATUS_FB_NAME, blk << 8,
604 				UMP_STREAM_FB_STR_OFF);
605 }
606 
607 /* Process a UMP Stream message */
608 static void process_ump_stream_msg(struct f_midi2_ep *ep, const u32 *data)
609 {
610 	struct f_midi2 *midi2 = ep->card;
611 	unsigned int format, status, blk;
612 
613 	format = ump_stream_message_format(*data);
614 	status = ump_stream_message_status(*data);
615 	switch (status) {
616 	case UMP_STREAM_MSG_STATUS_EP_DISCOVERY:
617 		if (format)
618 			return; // invalid
619 		if (data[1] & UMP_STREAM_MSG_REQUEST_EP_INFO)
620 			reply_ump_stream_ep_info(ep);
621 		if (data[1] & UMP_STREAM_MSG_REQUEST_DEVICE_INFO)
622 			reply_ump_stream_ep_device(ep);
623 		if (data[1] & UMP_STREAM_MSG_REQUEST_EP_NAME)
624 			reply_ump_stream_ep_name(ep);
625 		if (data[1] & UMP_STREAM_MSG_REQUEST_PRODUCT_ID)
626 			reply_ump_stream_ep_pid(ep);
627 		if (data[1] & UMP_STREAM_MSG_REQUEST_STREAM_CFG)
628 			reply_ump_stream_ep_config(ep);
629 		return;
630 	case UMP_STREAM_MSG_STATUS_STREAM_CFG_REQUEST:
631 		if (*data & UMP_STREAM_MSG_EP_INFO_CAP_MIDI2) {
632 			ep->info.protocol = 2;
633 			DBG(midi2, "Switching Protocol to MIDI2\n");
634 		} else {
635 			ep->info.protocol = 1;
636 			DBG(midi2, "Switching Protocol to MIDI1\n");
637 		}
638 		snd_ump_switch_protocol(ep->ump, to_ump_protocol(ep->info.protocol));
639 		reply_ump_stream_ep_config(ep);
640 		return;
641 	case UMP_STREAM_MSG_STATUS_FB_DISCOVERY:
642 		if (format)
643 			return; // invalid
644 		blk = (*data >> 8) & 0xff;
645 		if (blk == 0xff) {
646 			/* inquiry for all blocks */
647 			for (blk = 0; blk < ep->num_blks; blk++) {
648 				if (*data & UMP_STREAM_MSG_REQUEST_FB_INFO)
649 					reply_ump_stream_fb_info(ep, blk);
650 				if (*data & UMP_STREAM_MSG_REQUEST_FB_NAME)
651 					reply_ump_stream_fb_name(ep, blk);
652 			}
653 		} else if (blk < ep->num_blks) {
654 			/* only the specified block */
655 			if (*data & UMP_STREAM_MSG_REQUEST_FB_INFO)
656 				reply_ump_stream_fb_info(ep, blk);
657 			if (*data & UMP_STREAM_MSG_REQUEST_FB_NAME)
658 				reply_ump_stream_fb_name(ep, blk);
659 		}
660 		return;
661 	}
662 }
663 
664 /* Process UMP messages included in a USB request */
665 static void process_ump(struct f_midi2_ep *ep, const struct usb_request *req)
666 {
667 	const u32 *data = (u32 *)req->buf;
668 	int len = req->actual >> 2;
669 	const u32 *in_buf = ep->ump->input_buf;
670 
671 	for (; len > 0; len--, data++) {
672 		if (snd_ump_receive_ump_val(ep->ump, *data) <= 0)
673 			continue;
674 		if (ump_message_type(*in_buf) == UMP_MSG_TYPE_STREAM)
675 			process_ump_stream_msg(ep, in_buf);
676 	}
677 }
678 
679 /*
680  * MIDI 2.0 UMP USB request handling
681  */
682 
683 /* complete handler for UMP EP-out requests */
684 static void f_midi2_ep_out_complete(struct usb_ep *usb_ep,
685 				    struct usb_request *req)
686 {
687 	struct f_midi2_req_ctx *ctx = req->context;
688 	struct f_midi2_ep *ep = ctx->usb_ep->ep;
689 	struct f_midi2 *midi2 = ep->card;
690 	int status = req->status;
691 
692 	if (status) {
693 		DBG(midi2, "%s complete error %d: %d/%d\n",
694 		    usb_ep->name, status, req->actual, req->length);
695 		goto error;
696 	}
697 
698 	/* convert to UMP packet in native endianness */
699 	le32_to_cpu_array((u32 *)req->buf, req->actual >> 2);
700 
701 	if (midi2->info.process_ump)
702 		process_ump(ep, req);
703 
704 	snd_ump_receive(ep->ump, req->buf, req->actual & ~3);
705 
706 	if (midi2->operation_mode != MIDI_OP_MODE_MIDI2)
707 		goto error;
708 
709 	if (queue_request_ep_raw(req))
710 		goto error;
711 	return;
712 
713  error:
714 	put_empty_request(req);
715 }
716 
717 /* Transmit UMP packets received from user-space to the gadget */
718 static void process_ump_transmit(struct f_midi2_ep *ep)
719 {
720 	struct f_midi2_usb_ep *usb_ep = &ep->ep_in;
721 	struct f_midi2 *midi2 = ep->card;
722 	struct usb_request *req;
723 	int len;
724 
725 	if (!usb_ep->usb_ep->enabled)
726 		return;
727 
728 	for (;;) {
729 		req = get_empty_request(usb_ep);
730 		if (!req)
731 			break;
732 		len = snd_ump_transmit(ep->ump, (u32 *)req->buf,
733 				       midi2->info.req_buf_size);
734 		if (len <= 0) {
735 			put_empty_request(req);
736 			break;
737 		}
738 
739 		req->length = len;
740 		if (queue_request_ep_in(req) < 0)
741 			break;
742 	}
743 }
744 
745 /* Complete handler for UMP EP-in requests */
746 static void f_midi2_ep_in_complete(struct usb_ep *usb_ep,
747 				   struct usb_request *req)
748 {
749 	struct f_midi2_req_ctx *ctx = req->context;
750 	struct f_midi2_ep *ep = ctx->usb_ep->ep;
751 	struct f_midi2 *midi2 = ep->card;
752 	int status = req->status;
753 
754 	put_empty_request(req);
755 
756 	if (status) {
757 		DBG(midi2, "%s complete error %d: %d/%d\n",
758 		    usb_ep->name, status, req->actual, req->length);
759 		return;
760 	}
761 
762 	process_ump_transmit(ep);
763 }
764 
765 /*
766  * MIDI1 (altset 0) USB request handling
767  */
768 
769 /* process one MIDI byte -- copied from f_midi.c
770  *
771  * fill the packet or request if needed
772  * returns true if the request became empty (queued)
773  */
774 static bool process_midi1_byte(struct f_midi2 *midi2, u8 cable, u8 b,
775 			       struct usb_request **req_p)
776 {
777 	struct f_midi2_midi1_port *port = &midi2->midi1_port[cable];
778 	u8 p[4] = { cable << 4, 0, 0, 0 };
779 	int next_state = STATE_INITIAL;
780 	struct usb_request *req = *req_p;
781 
782 	switch (b) {
783 	case 0xf8 ... 0xff:
784 		/* System Real-Time Messages */
785 		p[0] |= 0x0f;
786 		p[1] = b;
787 		next_state = port->state;
788 		port->state = STATE_REAL_TIME;
789 		break;
790 
791 	case 0xf7:
792 		/* End of SysEx */
793 		switch (port->state) {
794 		case STATE_SYSEX_0:
795 			p[0] |= 0x05;
796 			p[1] = 0xf7;
797 			next_state = STATE_FINISHED;
798 			break;
799 		case STATE_SYSEX_1:
800 			p[0] |= 0x06;
801 			p[1] = port->data[0];
802 			p[2] = 0xf7;
803 			next_state = STATE_FINISHED;
804 			break;
805 		case STATE_SYSEX_2:
806 			p[0] |= 0x07;
807 			p[1] = port->data[0];
808 			p[2] = port->data[1];
809 			p[3] = 0xf7;
810 			next_state = STATE_FINISHED;
811 			break;
812 		default:
813 			/* Ignore byte */
814 			next_state = port->state;
815 			port->state = STATE_INITIAL;
816 		}
817 		break;
818 
819 	case 0xf0 ... 0xf6:
820 		/* System Common Messages */
821 		port->data[0] = port->data[1] = 0;
822 		port->state = STATE_INITIAL;
823 		switch (b) {
824 		case 0xf0:
825 			port->data[0] = b;
826 			port->data[1] = 0;
827 			next_state = STATE_SYSEX_1;
828 			break;
829 		case 0xf1:
830 		case 0xf3:
831 			port->data[0] = b;
832 			next_state = STATE_1PARAM;
833 			break;
834 		case 0xf2:
835 			port->data[0] = b;
836 			next_state = STATE_2PARAM_1;
837 			break;
838 		case 0xf4:
839 		case 0xf5:
840 			next_state = STATE_INITIAL;
841 			break;
842 		case 0xf6:
843 			p[0] |= 0x05;
844 			p[1] = 0xf6;
845 			next_state = STATE_FINISHED;
846 			break;
847 		}
848 		break;
849 
850 	case 0x80 ... 0xef:
851 		/*
852 		 * Channel Voice Messages, Channel Mode Messages
853 		 * and Control Change Messages.
854 		 */
855 		port->data[0] = b;
856 		port->data[1] = 0;
857 		port->state = STATE_INITIAL;
858 		if (b >= 0xc0 && b <= 0xdf)
859 			next_state = STATE_1PARAM;
860 		else
861 			next_state = STATE_2PARAM_1;
862 		break;
863 
864 	case 0x00 ... 0x7f:
865 		/* Message parameters */
866 		switch (port->state) {
867 		case STATE_1PARAM:
868 			if (port->data[0] < 0xf0)
869 				p[0] |= port->data[0] >> 4;
870 			else
871 				p[0] |= 0x02;
872 
873 			p[1] = port->data[0];
874 			p[2] = b;
875 			/* This is to allow Running State Messages */
876 			next_state = STATE_1PARAM;
877 			break;
878 		case STATE_2PARAM_1:
879 			port->data[1] = b;
880 			next_state = STATE_2PARAM_2;
881 			break;
882 		case STATE_2PARAM_2:
883 			if (port->data[0] < 0xf0)
884 				p[0] |= port->data[0] >> 4;
885 			else
886 				p[0] |= 0x03;
887 
888 			p[1] = port->data[0];
889 			p[2] = port->data[1];
890 			p[3] = b;
891 			/* This is to allow Running State Messages */
892 			next_state = STATE_2PARAM_1;
893 			break;
894 		case STATE_SYSEX_0:
895 			port->data[0] = b;
896 			next_state = STATE_SYSEX_1;
897 			break;
898 		case STATE_SYSEX_1:
899 			port->data[1] = b;
900 			next_state = STATE_SYSEX_2;
901 			break;
902 		case STATE_SYSEX_2:
903 			p[0] |= 0x04;
904 			p[1] = port->data[0];
905 			p[2] = port->data[1];
906 			p[3] = b;
907 			next_state = STATE_SYSEX_0;
908 			break;
909 		}
910 		break;
911 	}
912 
913 	/* States where we have to write into the USB request */
914 	if (next_state == STATE_FINISHED ||
915 	    port->state == STATE_SYSEX_2 ||
916 	    port->state == STATE_1PARAM ||
917 	    port->state == STATE_2PARAM_2 ||
918 	    port->state == STATE_REAL_TIME) {
919 		memcpy(req->buf + req->length, p, sizeof(p));
920 		req->length += sizeof(p);
921 
922 		if (next_state == STATE_FINISHED) {
923 			next_state = STATE_INITIAL;
924 			port->data[0] = port->data[1] = 0;
925 		}
926 
927 		if (midi2->info.req_buf_size - req->length <= 4) {
928 			queue_request_ep_raw(req);
929 			*req_p = NULL;
930 			return true;
931 		}
932 	}
933 
934 	port->state = next_state;
935 	return false;
936 }
937 
938 /* process all pending MIDI bytes in the internal buffer;
939  * returns true if the request gets empty
940  * returns false if all have been processed
941  */
942 static bool process_midi1_pending_buf(struct f_midi2 *midi2,
943 				      struct usb_request **req_p)
944 {
945 	unsigned int cable, c;
946 
947 	for (cable = 0; cable < midi2->num_midi1_in; cable++) {
948 		struct f_midi2_midi1_port *port = &midi2->midi1_port[cable];
949 
950 		if (!port->pending)
951 			continue;
952 		for (c = 0; c < port->pending; c++) {
953 			if (process_midi1_byte(midi2, cable, port->buf[c],
954 					       req_p)) {
955 				port->pending -= c;
956 				if (port->pending)
957 					memmove(port->buf, port->buf + c,
958 						port->pending);
959 				return true;
960 			}
961 		}
962 		port->pending = 0;
963 	}
964 
965 	return false;
966 }
967 
968 /* fill the MIDI bytes onto the temporary buffer
969  */
970 static void fill_midi1_pending_buf(struct f_midi2 *midi2, u8 cable, u8 *buf,
971 				   unsigned int size)
972 {
973 	struct f_midi2_midi1_port *port = &midi2->midi1_port[cable];
974 
975 	if (port->pending + size > sizeof(port->buf))
976 		return;
977 	memcpy(port->buf + port->pending, buf, size);
978 	port->pending += size;
979 }
980 
981 /* try to process data given from the associated UMP stream */
982 static void process_midi1_transmit(struct f_midi2 *midi2)
983 {
984 	struct f_midi2_usb_ep *usb_ep = &midi2->midi1_ep_in;
985 	struct f_midi2_ep *ep = &midi2->midi2_eps[0];
986 	struct usb_request *req = NULL;
987 	/* 12 is the largest outcome (4 MIDI1 cmds) for a single UMP packet */
988 	unsigned char outbuf[12];
989 	unsigned char group, cable;
990 	int len, size;
991 	u32 ump;
992 
993 	if (!usb_ep->usb_ep || !usb_ep->usb_ep->enabled)
994 		return;
995 
996 	for (;;) {
997 		if (!req) {
998 			req = get_empty_request(usb_ep);
999 			if (!req)
1000 				break;
1001 		}
1002 
1003 		if (process_midi1_pending_buf(midi2, &req))
1004 			continue;
1005 
1006 		len = snd_ump_transmit(ep->ump, &ump, 4);
1007 		if (len <= 0)
1008 			break;
1009 		if (snd_ump_receive_ump_val(ep->ump, ump) <= 0)
1010 			continue;
1011 		size = snd_ump_convert_from_ump(ep->ump->input_buf, outbuf,
1012 						&group);
1013 		if (size <= 0)
1014 			continue;
1015 		cable = ep->in_group_to_cable[group];
1016 		if (!cable)
1017 			continue;
1018 		cable--; /* to 0-base */
1019 		fill_midi1_pending_buf(midi2, cable, outbuf, size);
1020 	}
1021 
1022 	if (req) {
1023 		if (req->length)
1024 			queue_request_ep_raw(req);
1025 		else
1026 			put_empty_request(req);
1027 	}
1028 }
1029 
1030 /* complete handler for MIDI1 EP-in requests */
1031 static void f_midi2_midi1_ep_in_complete(struct usb_ep *usb_ep,
1032 					 struct usb_request *req)
1033 {
1034 	struct f_midi2_req_ctx *ctx = req->context;
1035 	struct f_midi2 *midi2 = ctx->usb_ep->card;
1036 	int status = req->status;
1037 
1038 	put_empty_request(req);
1039 
1040 	if (status) {
1041 		DBG(midi2, "%s complete error %d: %d/%d\n",
1042 		    usb_ep->name, status, req->actual, req->length);
1043 		return;
1044 	}
1045 
1046 	process_midi1_transmit(midi2);
1047 }
1048 
1049 /* complete handler for MIDI1 EP-out requests */
1050 static void f_midi2_midi1_ep_out_complete(struct usb_ep *usb_ep,
1051 					  struct usb_request *req)
1052 {
1053 	struct f_midi2_req_ctx *ctx = req->context;
1054 	struct f_midi2 *midi2 = ctx->usb_ep->card;
1055 	struct f_midi2_ep *ep;
1056 	struct ump_cvt_to_ump *cvt = &midi2->midi1_ump_cvt;
1057 	static const u8 midi1_packet_bytes[16] = {
1058 		0, 0, 2, 3, 3, 1, 2, 3, 3, 3, 3, 3, 2, 2, 3, 1
1059 	};
1060 	unsigned int group, cable, bytes, c, len;
1061 	int status = req->status;
1062 	const u8 *buf = req->buf;
1063 
1064 	if (status) {
1065 		DBG(midi2, "%s complete error %d: %d/%d\n",
1066 		    usb_ep->name, status, req->actual, req->length);
1067 		goto error;
1068 	}
1069 
1070 	len = req->actual >> 2;
1071 	for (; len; len--, buf += 4) {
1072 		cable = *buf >> 4;
1073 		ep = midi2->out_cable_mapping[cable].ep;
1074 		if (!ep)
1075 			continue;
1076 		group = midi2->out_cable_mapping[cable].group;
1077 		bytes = midi1_packet_bytes[*buf & 0x0f];
1078 		for (c = 0; c < bytes; c++) {
1079 			snd_ump_convert_to_ump(cvt, group,
1080 					       to_ump_protocol(ep->info.protocol),
1081 					       buf[c + 1]);
1082 			if (cvt->ump_bytes) {
1083 				snd_ump_receive(ep->ump, cvt->ump,
1084 						cvt->ump_bytes);
1085 				cvt->ump_bytes = 0;
1086 			}
1087 		}
1088 	}
1089 
1090 	if (midi2->operation_mode != MIDI_OP_MODE_MIDI1)
1091 		goto error;
1092 
1093 	if (queue_request_ep_raw(req))
1094 		goto error;
1095 	return;
1096 
1097  error:
1098 	put_empty_request(req);
1099 }
1100 
1101 /*
1102  * Common EP handling helpers
1103  */
1104 
1105 /* Start MIDI EP */
1106 static int f_midi2_start_ep(struct f_midi2_usb_ep *usb_ep,
1107 			    struct usb_function *fn)
1108 {
1109 	int err;
1110 
1111 	if (!usb_ep->usb_ep)
1112 		return 0;
1113 
1114 	usb_ep_disable(usb_ep->usb_ep);
1115 	err = config_ep_by_speed(usb_ep->card->gadget, fn, usb_ep->usb_ep);
1116 	if (err)
1117 		return err;
1118 	return usb_ep_enable(usb_ep->usb_ep);
1119 }
1120 
1121 /* Drop pending requests */
1122 static void f_midi2_drop_reqs(struct f_midi2_usb_ep *usb_ep)
1123 {
1124 	int i;
1125 
1126 	if (!usb_ep->usb_ep || !usb_ep->num_reqs)
1127 		return;
1128 
1129 	for (i = 0; i < usb_ep->num_reqs; i++) {
1130 		if (!test_bit(i, &usb_ep->free_reqs) && usb_ep->reqs[i].req) {
1131 			usb_ep_dequeue(usb_ep->usb_ep, usb_ep->reqs[i].req);
1132 			set_bit(i, &usb_ep->free_reqs);
1133 		}
1134 	}
1135 }
1136 
1137 /* Allocate requests for the given EP */
1138 static int f_midi2_alloc_ep_reqs(struct f_midi2_usb_ep *usb_ep)
1139 {
1140 	struct f_midi2 *midi2 = usb_ep->card;
1141 	int i;
1142 
1143 	if (!usb_ep->usb_ep)
1144 		return 0;
1145 	if (!usb_ep->reqs)
1146 		return -EINVAL;
1147 
1148 	for (i = 0; i < midi2->info.num_reqs; i++) {
1149 		if (usb_ep->reqs[i].req)
1150 			continue;
1151 		usb_ep->reqs[i].req = alloc_ep_req(usb_ep->usb_ep,
1152 						   midi2->info.req_buf_size);
1153 		if (!usb_ep->reqs[i].req)
1154 			return -ENOMEM;
1155 		usb_ep->reqs[i].req->context = &usb_ep->reqs[i];
1156 	}
1157 	return 0;
1158 }
1159 
1160 /* Free allocated requests */
1161 static void f_midi2_free_ep_reqs(struct f_midi2_usb_ep *usb_ep)
1162 {
1163 	struct f_midi2 *midi2 = usb_ep->card;
1164 	int i;
1165 
1166 	for (i = 0; i < midi2->info.num_reqs; i++) {
1167 		if (!usb_ep->reqs[i].req)
1168 			continue;
1169 		free_ep_req(usb_ep->usb_ep, usb_ep->reqs[i].req);
1170 		usb_ep->reqs[i].req = NULL;
1171 	}
1172 }
1173 
1174 /* Initialize EP */
1175 static int f_midi2_init_ep(struct f_midi2 *midi2, struct f_midi2_ep *ep,
1176 			   struct f_midi2_usb_ep *usb_ep,
1177 			   void *desc,
1178 			   void (*complete)(struct usb_ep *usb_ep,
1179 					    struct usb_request *req))
1180 {
1181 	int i;
1182 
1183 	usb_ep->card = midi2;
1184 	usb_ep->ep = ep;
1185 	usb_ep->usb_ep = usb_ep_autoconfig(midi2->gadget, desc);
1186 	if (!usb_ep->usb_ep)
1187 		return -ENODEV;
1188 	usb_ep->complete = complete;
1189 
1190 	usb_ep->reqs = kcalloc(midi2->info.num_reqs, sizeof(*usb_ep->reqs),
1191 			       GFP_KERNEL);
1192 	if (!usb_ep->reqs)
1193 		return -ENOMEM;
1194 	for (i = 0; i < midi2->info.num_reqs; i++) {
1195 		usb_ep->reqs[i].index = i;
1196 		usb_ep->reqs[i].usb_ep = usb_ep;
1197 		set_bit(i, &usb_ep->free_reqs);
1198 		usb_ep->num_reqs++;
1199 	}
1200 
1201 	return 0;
1202 }
1203 
1204 /* Free EP */
1205 static void f_midi2_free_ep(struct f_midi2_usb_ep *usb_ep)
1206 {
1207 	f_midi2_drop_reqs(usb_ep);
1208 
1209 	f_midi2_free_ep_reqs(usb_ep);
1210 
1211 	kfree(usb_ep->reqs);
1212 	usb_ep->num_reqs = 0;
1213 	usb_ep->free_reqs = 0;
1214 	usb_ep->reqs = NULL;
1215 }
1216 
1217 /* Queue requests for EP-out at start */
1218 static void f_midi2_queue_out_reqs(struct f_midi2_usb_ep *usb_ep)
1219 {
1220 	int i, err;
1221 
1222 	if (!usb_ep->usb_ep)
1223 		return;
1224 
1225 	for (i = 0; i < usb_ep->num_reqs; i++) {
1226 		if (!test_bit(i, &usb_ep->free_reqs) || !usb_ep->reqs[i].req)
1227 			continue;
1228 		usb_ep->reqs[i].req->complete = usb_ep->complete;
1229 		err = usb_ep_queue(usb_ep->usb_ep, usb_ep->reqs[i].req,
1230 				   GFP_ATOMIC);
1231 		if (!err)
1232 			clear_bit(i, &usb_ep->free_reqs);
1233 	}
1234 }
1235 
1236 /*
1237  * Gadget Function callbacks
1238  */
1239 
1240 /* stop both IN and OUT EPs */
1241 static void f_midi2_stop_eps(struct f_midi2_usb_ep *ep_in,
1242 			     struct f_midi2_usb_ep *ep_out)
1243 {
1244 	f_midi2_drop_reqs(ep_in);
1245 	f_midi2_drop_reqs(ep_out);
1246 	f_midi2_free_ep_reqs(ep_in);
1247 	f_midi2_free_ep_reqs(ep_out);
1248 }
1249 
1250 /* start/queue both IN and OUT EPs */
1251 static int f_midi2_start_eps(struct f_midi2_usb_ep *ep_in,
1252 			     struct f_midi2_usb_ep *ep_out,
1253 			     struct usb_function *fn)
1254 {
1255 	int err;
1256 
1257 	err = f_midi2_start_ep(ep_in, fn);
1258 	if (err)
1259 		return err;
1260 	err = f_midi2_start_ep(ep_out, fn);
1261 	if (err)
1262 		return err;
1263 
1264 	err = f_midi2_alloc_ep_reqs(ep_in);
1265 	if (err)
1266 		return err;
1267 	err = f_midi2_alloc_ep_reqs(ep_out);
1268 	if (err)
1269 		return err;
1270 
1271 	f_midi2_queue_out_reqs(ep_out);
1272 	return 0;
1273 }
1274 
1275 /* gadget function set_alt callback */
1276 static int f_midi2_set_alt(struct usb_function *fn, unsigned int intf,
1277 			   unsigned int alt)
1278 {
1279 	struct f_midi2 *midi2 = func_to_midi2(fn);
1280 	struct f_midi2_ep *ep;
1281 	int i, op_mode, err;
1282 
1283 	if (intf != midi2->midi_if || alt > 1)
1284 		return 0;
1285 
1286 	if (alt == 0)
1287 		op_mode = MIDI_OP_MODE_MIDI1;
1288 	else
1289 		op_mode = MIDI_OP_MODE_MIDI2;
1290 
1291 	if (midi2->operation_mode == op_mode)
1292 		return 0;
1293 
1294 	midi2->operation_mode = op_mode;
1295 
1296 	if (op_mode != MIDI_OP_MODE_MIDI1)
1297 		f_midi2_stop_eps(&midi2->midi1_ep_in, &midi2->midi1_ep_out);
1298 
1299 	if (op_mode != MIDI_OP_MODE_MIDI2) {
1300 		for (i = 0; i < midi2->num_eps; i++) {
1301 			ep = &midi2->midi2_eps[i];
1302 			f_midi2_stop_eps(&ep->ep_in, &ep->ep_out);
1303 		}
1304 	}
1305 
1306 	if (op_mode == MIDI_OP_MODE_MIDI1)
1307 		return f_midi2_start_eps(&midi2->midi1_ep_in,
1308 					 &midi2->midi1_ep_out, fn);
1309 
1310 	if (op_mode == MIDI_OP_MODE_MIDI2) {
1311 		for (i = 0; i < midi2->num_eps; i++) {
1312 			ep = &midi2->midi2_eps[i];
1313 
1314 			err = f_midi2_start_eps(&ep->ep_in, &ep->ep_out, fn);
1315 			if (err)
1316 				return err;
1317 		}
1318 	}
1319 
1320 	return 0;
1321 }
1322 
1323 /* gadget function get_alt callback */
1324 static int f_midi2_get_alt(struct usb_function *fn, unsigned int intf)
1325 {
1326 	struct f_midi2 *midi2 = func_to_midi2(fn);
1327 
1328 	if (intf == midi2->midi_if &&
1329 	    midi2->operation_mode == MIDI_OP_MODE_MIDI2)
1330 		return 1;
1331 	return 0;
1332 }
1333 
1334 /* convert UMP direction to USB MIDI 2.0 direction */
1335 static unsigned int ump_to_usb_dir(unsigned int ump_dir)
1336 {
1337 	switch (ump_dir) {
1338 	case SNDRV_UMP_DIR_INPUT:
1339 		return USB_MS_GR_TRM_BLOCK_TYPE_INPUT_ONLY;
1340 	case SNDRV_UMP_DIR_OUTPUT:
1341 		return USB_MS_GR_TRM_BLOCK_TYPE_OUTPUT_ONLY;
1342 	default:
1343 		return USB_MS_GR_TRM_BLOCK_TYPE_BIDIRECTIONAL;
1344 	}
1345 }
1346 
1347 /* assign GTB descriptors (for the given request) */
1348 static void assign_block_descriptors(struct f_midi2 *midi2,
1349 				     struct usb_request *req,
1350 				     int max_len)
1351 {
1352 	struct usb_ms20_gr_trm_block_header_descriptor header;
1353 	struct usb_ms20_gr_trm_block_descriptor *desc;
1354 	struct f_midi2_block_info *b;
1355 	struct f_midi2_ep *ep;
1356 	int i, blk, len;
1357 	char *data;
1358 
1359 	len = sizeof(gtb_header_desc) + sizeof(gtb_desc) * midi2->total_blocks;
1360 	if (WARN_ON(len > midi2->info.req_buf_size))
1361 		return;
1362 
1363 	header = gtb_header_desc;
1364 	header.wTotalLength = cpu_to_le16(len);
1365 	if (max_len < len) {
1366 		len = min_t(int, len, sizeof(header));
1367 		memcpy(req->buf, &header, len);
1368 		req->length = len;
1369 		req->zero = len < max_len;
1370 		return;
1371 	}
1372 
1373 	memcpy(req->buf, &header, sizeof(header));
1374 	data = req->buf + sizeof(header);
1375 	for (i = 0; i < midi2->num_eps; i++) {
1376 		ep = &midi2->midi2_eps[i];
1377 		for (blk = 0; blk < ep->num_blks; blk++) {
1378 			b = &ep->blks[blk].info;
1379 			desc = (struct usb_ms20_gr_trm_block_descriptor *)data;
1380 
1381 			*desc = gtb_desc;
1382 			desc->bGrpTrmBlkID = ep->blks[blk].gtb_id;
1383 			desc->bGrpTrmBlkType = ump_to_usb_dir(b->direction);
1384 			desc->nGroupTrm = b->first_group;
1385 			desc->nNumGroupTrm = b->num_groups;
1386 			desc->iBlockItem = ep->blks[blk].string_id;
1387 
1388 			if (ep->info.protocol == 2)
1389 				desc->bMIDIProtocol = USB_MS_MIDI_PROTO_2_0;
1390 			else
1391 				desc->bMIDIProtocol = USB_MS_MIDI_PROTO_1_0_128;
1392 
1393 			if (b->is_midi1 == 2) {
1394 				desc->wMaxInputBandwidth = cpu_to_le16(1);
1395 				desc->wMaxOutputBandwidth = cpu_to_le16(1);
1396 			}
1397 
1398 			data += sizeof(*desc);
1399 		}
1400 	}
1401 
1402 	req->length = len;
1403 	req->zero = len < max_len;
1404 }
1405 
1406 /* gadget function setup callback: handle GTB requests */
1407 static int f_midi2_setup(struct usb_function *fn,
1408 			 const struct usb_ctrlrequest *ctrl)
1409 {
1410 	struct f_midi2 *midi2 = func_to_midi2(fn);
1411 	struct usb_composite_dev *cdev = fn->config->cdev;
1412 	struct usb_request *req = cdev->req;
1413 	u16 value, length;
1414 
1415 	if ((ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD ||
1416 	    ctrl->bRequest != USB_REQ_GET_DESCRIPTOR)
1417 		return -EOPNOTSUPP;
1418 
1419 	value = le16_to_cpu(ctrl->wValue);
1420 	length = le16_to_cpu(ctrl->wLength);
1421 
1422 	if ((value >> 8) != USB_DT_CS_GR_TRM_BLOCK)
1423 		return -EOPNOTSUPP;
1424 
1425 	/* handle only altset 1 */
1426 	if ((value & 0xff) != 1)
1427 		return -EOPNOTSUPP;
1428 
1429 	assign_block_descriptors(midi2, req, length);
1430 	return usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1431 }
1432 
1433 /* gadget function disable callback */
1434 static void f_midi2_disable(struct usb_function *fn)
1435 {
1436 	struct f_midi2 *midi2 = func_to_midi2(fn);
1437 
1438 	midi2->operation_mode = MIDI_OP_MODE_UNSET;
1439 }
1440 
1441 /*
1442  * ALSA UMP ops: most of them are NOPs, only trigger for write is needed
1443  */
1444 static int f_midi2_ump_open(struct snd_ump_endpoint *ump, int dir)
1445 {
1446 	return 0;
1447 }
1448 
1449 static void f_midi2_ump_close(struct snd_ump_endpoint *ump, int dir)
1450 {
1451 }
1452 
1453 static void f_midi2_ump_trigger(struct snd_ump_endpoint *ump, int dir, int up)
1454 {
1455 	struct f_midi2_ep *ep = ump->private_data;
1456 	struct f_midi2 *midi2 = ep->card;
1457 
1458 	if (up && dir == SNDRV_RAWMIDI_STREAM_OUTPUT) {
1459 		switch (midi2->operation_mode) {
1460 		case MIDI_OP_MODE_MIDI1:
1461 			process_midi1_transmit(midi2);
1462 			break;
1463 		case MIDI_OP_MODE_MIDI2:
1464 			process_ump_transmit(ep);
1465 			break;
1466 		}
1467 	}
1468 }
1469 
1470 static void f_midi2_ump_drain(struct snd_ump_endpoint *ump, int dir)
1471 {
1472 }
1473 
1474 static const struct snd_ump_ops f_midi2_ump_ops = {
1475 	.open = f_midi2_ump_open,
1476 	.close = f_midi2_ump_close,
1477 	.trigger = f_midi2_ump_trigger,
1478 	.drain = f_midi2_ump_drain,
1479 };
1480 
1481 /*
1482  * "Operation Mode" control element
1483  */
1484 static int f_midi2_operation_mode_info(struct snd_kcontrol *kcontrol,
1485 				       struct snd_ctl_elem_info *uinfo)
1486 {
1487 	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
1488 	uinfo->count = 1;
1489 	uinfo->value.integer.min = MIDI_OP_MODE_UNSET;
1490 	uinfo->value.integer.max = MIDI_OP_MODE_MIDI2;
1491 	return 0;
1492 }
1493 
1494 static int f_midi2_operation_mode_get(struct snd_kcontrol *kcontrol,
1495 				      struct snd_ctl_elem_value *ucontrol)
1496 {
1497 	struct f_midi2 *midi2 = snd_kcontrol_chip(kcontrol);
1498 
1499 	ucontrol->value.integer.value[0] = midi2->operation_mode;
1500 	return 0;
1501 }
1502 
1503 static const struct snd_kcontrol_new operation_mode_ctl = {
1504 	.iface = SNDRV_CTL_ELEM_IFACE_RAWMIDI,
1505 	.name = "Operation Mode",
1506 	.access = SNDRV_CTL_ELEM_ACCESS_READ | SNDRV_CTL_ELEM_ACCESS_VOLATILE,
1507 	.info = f_midi2_operation_mode_info,
1508 	.get = f_midi2_operation_mode_get,
1509 };
1510 
1511 /*
1512  * ALSA UMP instance creation / deletion
1513  */
1514 static void f_midi2_free_card(struct f_midi2 *midi2)
1515 {
1516 	if (midi2->card) {
1517 		snd_card_free_when_closed(midi2->card);
1518 		midi2->card = NULL;
1519 	}
1520 }
1521 
1522 /* use a reverse direction for the gadget host */
1523 static int reverse_dir(int dir)
1524 {
1525 	if (!dir || dir == SNDRV_UMP_DIR_BIDIRECTION)
1526 		return dir;
1527 	return (dir == SNDRV_UMP_DIR_OUTPUT) ?
1528 		SNDRV_UMP_DIR_INPUT : SNDRV_UMP_DIR_OUTPUT;
1529 }
1530 
1531 static int f_midi2_create_card(struct f_midi2 *midi2)
1532 {
1533 	struct snd_card *card;
1534 	struct snd_ump_endpoint *ump;
1535 	struct f_midi2_ep *ep;
1536 	int i, id, blk, err;
1537 	__be32 sw;
1538 
1539 	err = snd_card_new(&midi2->gadget->dev, -1, NULL, THIS_MODULE, 0,
1540 			   &card);
1541 	if (err < 0)
1542 		return err;
1543 	midi2->card = card;
1544 
1545 	strcpy(card->driver, "f_midi2");
1546 	strcpy(card->shortname, "MIDI 2.0 Gadget");
1547 	strcpy(card->longname, "MIDI 2.0 Gadget");
1548 
1549 	id = 0;
1550 	for (i = 0; i < midi2->num_eps; i++) {
1551 		ep = &midi2->midi2_eps[i];
1552 		err = snd_ump_endpoint_new(card, "MIDI 2.0 Gadget", id,
1553 					   1, 1, &ump);
1554 		if (err < 0)
1555 			goto error;
1556 		id++;
1557 
1558 		ep->ump = ump;
1559 		ump->no_process_stream = true;
1560 		ump->private_data = ep;
1561 		ump->ops = &f_midi2_ump_ops;
1562 		if (midi2->info.static_block)
1563 			ump->info.flags |= SNDRV_UMP_EP_INFO_STATIC_BLOCKS;
1564 		ump->info.protocol_caps = (ep->info.protocol_caps & 3) << 8;
1565 		ump->info.protocol = to_ump_protocol(ep->info.protocol);
1566 		ump->info.version = 0x0101;
1567 		ump->info.family_id = ep->info.family;
1568 		ump->info.model_id = ep->info.model;
1569 		ump->info.manufacturer_id = ep->info.manufacturer & 0xffffff;
1570 		sw = cpu_to_be32(ep->info.sw_revision);
1571 		memcpy(ump->info.sw_revision, &sw, 4);
1572 
1573 		strscpy(ump->info.name, ump_ep_name(ep),
1574 			sizeof(ump->info.name));
1575 		strscpy(ump->info.product_id, ump_product_id(ep),
1576 			sizeof(ump->info.product_id));
1577 		strscpy(ump->core.name, ump->info.name, sizeof(ump->core.name));
1578 
1579 		for (blk = 0; blk < ep->num_blks; blk++) {
1580 			const struct f_midi2_block_info *b = &ep->blks[blk].info;
1581 			struct snd_ump_block *fb;
1582 
1583 			err = snd_ump_block_new(ump, blk,
1584 						reverse_dir(b->direction),
1585 						b->first_group, b->num_groups,
1586 						&ep->blks[blk].fb);
1587 			if (err < 0)
1588 				goto error;
1589 			fb = ep->blks[blk].fb;
1590 			fb->info.active = !!b->active;
1591 			fb->info.midi_ci_version = b->midi_ci_version;
1592 			fb->info.ui_hint = reverse_dir(b->ui_hint);
1593 			fb->info.sysex8_streams = b->sysex8_streams;
1594 			fb->info.flags |= b->is_midi1;
1595 			strscpy(fb->info.name, ump_fb_name(b),
1596 				sizeof(fb->info.name));
1597 		}
1598 	}
1599 
1600 	for (i = 0; i < midi2->num_eps; i++) {
1601 		err = snd_ump_attach_legacy_rawmidi(midi2->midi2_eps[i].ump,
1602 						    "Legacy MIDI", id);
1603 		if (err < 0)
1604 			goto error;
1605 		id++;
1606 	}
1607 
1608 	err = snd_ctl_add(card, snd_ctl_new1(&operation_mode_ctl, midi2));
1609 	if (err < 0)
1610 		goto error;
1611 
1612 	err = snd_card_register(card);
1613 	if (err < 0)
1614 		goto error;
1615 
1616 	return 0;
1617 
1618  error:
1619 	f_midi2_free_card(midi2);
1620 	return err;
1621 }
1622 
1623 /*
1624  * Creation of USB descriptors
1625  */
1626 struct f_midi2_usb_config {
1627 	struct usb_descriptor_header **list;
1628 	unsigned int size;
1629 	unsigned int alloc;
1630 
1631 	/* MIDI 1.0 jacks */
1632 	unsigned char jack_in, jack_out, jack_id;
1633 	struct usb_midi_in_jack_descriptor jack_ins[MAX_CABLES];
1634 	struct usb_midi_out_jack_descriptor_1 jack_outs[MAX_CABLES];
1635 };
1636 
1637 static int append_config(struct f_midi2_usb_config *config, void *d)
1638 {
1639 	unsigned int size;
1640 	void *buf;
1641 
1642 	if (config->size + 2 >= config->alloc) {
1643 		size = config->size + 16;
1644 		buf = krealloc(config->list, size * sizeof(void *), GFP_KERNEL);
1645 		if (!buf)
1646 			return -ENOMEM;
1647 		config->list = buf;
1648 		config->alloc = size;
1649 	}
1650 
1651 	config->list[config->size] = d;
1652 	config->size++;
1653 	config->list[config->size] = NULL;
1654 	return 0;
1655 }
1656 
1657 static int append_configs(struct f_midi2_usb_config *config, void **d)
1658 {
1659 	int err;
1660 
1661 	for (; *d; d++) {
1662 		err = append_config(config, *d);
1663 		if (err)
1664 			return err;
1665 	}
1666 	return 0;
1667 }
1668 
1669 static int append_midi1_in_jack(struct f_midi2 *midi2,
1670 				struct f_midi2_usb_config *config,
1671 				struct midi1_cable_mapping *map,
1672 				unsigned int type)
1673 {
1674 	struct usb_midi_in_jack_descriptor *jack =
1675 		&config->jack_ins[config->jack_in++];
1676 	int id = ++config->jack_id;
1677 	int err;
1678 
1679 	jack->bLength = 0x06;
1680 	jack->bDescriptorType = USB_DT_CS_INTERFACE;
1681 	jack->bDescriptorSubtype = USB_MS_MIDI_IN_JACK;
1682 	jack->bJackType = type;
1683 	jack->bJackID = id;
1684 	/* use the corresponding block name as jack name */
1685 	if (map->ep)
1686 		jack->iJack = map->ep->blks[map->block].string_id;
1687 
1688 	err = append_config(config, jack);
1689 	if (err < 0)
1690 		return err;
1691 	return id;
1692 }
1693 
1694 static int append_midi1_out_jack(struct f_midi2 *midi2,
1695 				 struct f_midi2_usb_config *config,
1696 				 struct midi1_cable_mapping *map,
1697 				 unsigned int type, unsigned int source)
1698 {
1699 	struct usb_midi_out_jack_descriptor_1 *jack =
1700 		&config->jack_outs[config->jack_out++];
1701 	int id = ++config->jack_id;
1702 	int err;
1703 
1704 	jack->bLength = 0x09;
1705 	jack->bDescriptorType = USB_DT_CS_INTERFACE;
1706 	jack->bDescriptorSubtype = USB_MS_MIDI_OUT_JACK;
1707 	jack->bJackType = type;
1708 	jack->bJackID = id;
1709 	jack->bNrInputPins = 1;
1710 	jack->pins[0].baSourceID = source;
1711 	jack->pins[0].baSourcePin = 0x01;
1712 	/* use the corresponding block name as jack name */
1713 	if (map->ep)
1714 		jack->iJack = map->ep->blks[map->block].string_id;
1715 
1716 	err = append_config(config, jack);
1717 	if (err < 0)
1718 		return err;
1719 	return id;
1720 }
1721 
1722 static int f_midi2_create_usb_configs(struct f_midi2 *midi2,
1723 				      struct f_midi2_usb_config *config,
1724 				      int speed)
1725 {
1726 	void **midi1_in_eps, **midi1_out_eps;
1727 	int i, jack, total;
1728 	int err;
1729 
1730 	switch (speed) {
1731 	default:
1732 	case USB_SPEED_HIGH:
1733 		midi2_midi1_ep_out_desc.wMaxPacketSize = cpu_to_le16(512);
1734 		midi2_midi1_ep_in_desc.wMaxPacketSize = cpu_to_le16(512);
1735 		for (i = 0; i < midi2->num_eps; i++)
1736 			midi2_midi2_ep_out_desc[i].wMaxPacketSize =
1737 				cpu_to_le16(512);
1738 		fallthrough;
1739 	case USB_SPEED_FULL:
1740 		midi1_in_eps = midi2_midi1_ep_in_descs;
1741 		midi1_out_eps = midi2_midi1_ep_out_descs;
1742 		break;
1743 	case USB_SPEED_SUPER:
1744 		midi2_midi1_ep_out_desc.wMaxPacketSize = cpu_to_le16(1024);
1745 		midi2_midi1_ep_in_desc.wMaxPacketSize = cpu_to_le16(1024);
1746 		for (i = 0; i < midi2->num_eps; i++)
1747 			midi2_midi2_ep_out_desc[i].wMaxPacketSize =
1748 				cpu_to_le16(1024);
1749 		midi1_in_eps = midi2_midi1_ep_in_ss_descs;
1750 		midi1_out_eps = midi2_midi1_ep_out_ss_descs;
1751 		break;
1752 	}
1753 
1754 	err = append_configs(config, midi2_audio_descs);
1755 	if (err < 0)
1756 		return err;
1757 
1758 	if (midi2->num_midi1_in && midi2->num_midi1_out)
1759 		midi2_midi1_if_desc.bNumEndpoints = 2;
1760 	else
1761 		midi2_midi1_if_desc.bNumEndpoints = 1;
1762 
1763 	err = append_configs(config, midi2_midi1_descs);
1764 	if (err < 0)
1765 		return err;
1766 
1767 	total = USB_DT_MS_HEADER_SIZE;
1768 	if (midi2->num_midi1_out) {
1769 		midi2_midi1_ep_out_class_desc.bLength =
1770 			USB_DT_MS_ENDPOINT_SIZE(midi2->num_midi1_out);
1771 		total += midi2_midi1_ep_out_class_desc.bLength;
1772 		midi2_midi1_ep_out_class_desc.bNumEmbMIDIJack =
1773 			midi2->num_midi1_out;
1774 		total += midi2->num_midi1_out *
1775 			(USB_DT_MIDI_IN_SIZE + USB_DT_MIDI_OUT_SIZE(1));
1776 		for (i = 0; i < midi2->num_midi1_out; i++) {
1777 			jack = append_midi1_in_jack(midi2, config,
1778 						    &midi2->in_cable_mapping[i],
1779 						    USB_MS_EMBEDDED);
1780 			if (jack < 0)
1781 				return jack;
1782 			midi2_midi1_ep_out_class_desc.baAssocJackID[i] = jack;
1783 			jack = append_midi1_out_jack(midi2, config,
1784 						     &midi2->in_cable_mapping[i],
1785 						     USB_MS_EXTERNAL, jack);
1786 			if (jack < 0)
1787 				return jack;
1788 		}
1789 	}
1790 
1791 	if (midi2->num_midi1_in) {
1792 		midi2_midi1_ep_in_class_desc.bLength =
1793 			USB_DT_MS_ENDPOINT_SIZE(midi2->num_midi1_in);
1794 		total += midi2_midi1_ep_in_class_desc.bLength;
1795 		midi2_midi1_ep_in_class_desc.bNumEmbMIDIJack =
1796 			midi2->num_midi1_in;
1797 		total += midi2->num_midi1_in *
1798 			(USB_DT_MIDI_IN_SIZE + USB_DT_MIDI_OUT_SIZE(1));
1799 		for (i = 0; i < midi2->num_midi1_in; i++) {
1800 			jack = append_midi1_in_jack(midi2, config,
1801 						    &midi2->out_cable_mapping[i],
1802 						    USB_MS_EXTERNAL);
1803 			if (jack < 0)
1804 				return jack;
1805 			jack = append_midi1_out_jack(midi2, config,
1806 						     &midi2->out_cable_mapping[i],
1807 						     USB_MS_EMBEDDED, jack);
1808 			if (jack < 0)
1809 				return jack;
1810 			midi2_midi1_ep_in_class_desc.baAssocJackID[i] = jack;
1811 		}
1812 	}
1813 
1814 	midi2_midi1_class_desc.wTotalLength = cpu_to_le16(total);
1815 
1816 	if (midi2->num_midi1_out) {
1817 		err = append_configs(config, midi1_out_eps);
1818 		if (err < 0)
1819 			return err;
1820 	}
1821 	if (midi2->num_midi1_in) {
1822 		err = append_configs(config, midi1_in_eps);
1823 		if (err < 0)
1824 			return err;
1825 	}
1826 
1827 	err = append_configs(config, midi2_midi2_descs);
1828 	if (err < 0)
1829 		return err;
1830 
1831 	for (i = 0; i < midi2->num_eps; i++) {
1832 		err = append_config(config, &midi2_midi2_ep_out_desc[i]);
1833 		if (err < 0)
1834 			return err;
1835 		if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS) {
1836 			err = append_config(config, &midi2_midi2_ep_out_ss_comp_desc);
1837 			if (err < 0)
1838 				return err;
1839 		}
1840 		err = append_config(config, &midi2_midi2_ep_out_class_desc[i]);
1841 		if (err < 0)
1842 			return err;
1843 		err = append_config(config, &midi2_midi2_ep_in_desc[i]);
1844 		if (err < 0)
1845 			return err;
1846 		if (speed == USB_SPEED_SUPER || speed == USB_SPEED_SUPER_PLUS) {
1847 			err = append_config(config, &midi2_midi2_ep_in_ss_comp_desc);
1848 			if (err < 0)
1849 				return err;
1850 		}
1851 		err = append_config(config, &midi2_midi2_ep_in_class_desc[i]);
1852 		if (err < 0)
1853 			return err;
1854 	}
1855 
1856 	return 0;
1857 }
1858 
1859 static void f_midi2_free_usb_configs(struct f_midi2_usb_config *config)
1860 {
1861 	kfree(config->list);
1862 	memset(config, 0, sizeof(*config));
1863 }
1864 
1865 /* as we use the static descriptors for simplicity, serialize bind call */
1866 static DEFINE_MUTEX(f_midi2_desc_mutex);
1867 
1868 /* fill MIDI2 EP class-specific descriptor */
1869 static void fill_midi2_class_desc(struct f_midi2_ep *ep,
1870 				  struct usb_ms20_endpoint_descriptor_32 *cdesc)
1871 {
1872 	int blk;
1873 
1874 	cdesc->bLength = USB_DT_MS20_ENDPOINT_SIZE(ep->num_blks);
1875 	cdesc->bDescriptorType = USB_DT_CS_ENDPOINT;
1876 	cdesc->bDescriptorSubtype = USB_MS_GENERAL_2_0;
1877 	cdesc->bNumGrpTrmBlock = ep->num_blks;
1878 	for (blk = 0; blk < ep->num_blks; blk++)
1879 		cdesc->baAssoGrpTrmBlkID[blk] = ep->blks[blk].gtb_id;
1880 }
1881 
1882 /* initialize MIDI2 EP-in */
1883 static int f_midi2_init_midi2_ep_in(struct f_midi2 *midi2, int index)
1884 {
1885 	struct f_midi2_ep *ep = &midi2->midi2_eps[index];
1886 	struct usb_endpoint_descriptor *desc = &midi2_midi2_ep_in_desc[index];
1887 
1888 	desc->bLength = USB_DT_ENDPOINT_SIZE;
1889 	desc->bDescriptorType = USB_DT_ENDPOINT;
1890 	desc->bEndpointAddress = USB_DIR_IN;
1891 	desc->bmAttributes = USB_ENDPOINT_XFER_INT;
1892 	desc->wMaxPacketSize = cpu_to_le16(EP_MAX_PACKET_INT);
1893 	desc->bInterval = 1;
1894 
1895 	fill_midi2_class_desc(ep, &midi2_midi2_ep_in_class_desc[index]);
1896 
1897 	return f_midi2_init_ep(midi2, ep, &ep->ep_in, desc,
1898 			       f_midi2_ep_in_complete);
1899 }
1900 
1901 /* initialize MIDI2 EP-out */
1902 static int f_midi2_init_midi2_ep_out(struct f_midi2 *midi2, int index)
1903 {
1904 	struct f_midi2_ep *ep = &midi2->midi2_eps[index];
1905 	struct usb_endpoint_descriptor *desc = &midi2_midi2_ep_out_desc[index];
1906 
1907 	desc->bLength = USB_DT_ENDPOINT_SIZE;
1908 	desc->bDescriptorType = USB_DT_ENDPOINT;
1909 	desc->bEndpointAddress = USB_DIR_OUT;
1910 	desc->bmAttributes = USB_ENDPOINT_XFER_BULK;
1911 
1912 	fill_midi2_class_desc(ep, &midi2_midi2_ep_out_class_desc[index]);
1913 
1914 	return f_midi2_init_ep(midi2, ep, &ep->ep_out, desc,
1915 			       f_midi2_ep_out_complete);
1916 }
1917 
1918 /* gadget function bind callback */
1919 static int f_midi2_bind(struct usb_configuration *c, struct usb_function *f)
1920 {
1921 	struct usb_composite_dev *cdev = c->cdev;
1922 	struct f_midi2 *midi2 = func_to_midi2(f);
1923 	struct f_midi2_ep *ep;
1924 	struct f_midi2_usb_config config = {};
1925 	struct usb_gadget_strings string_fn = {
1926 		.language = 0x0409,	/* en-us */
1927 		.strings = midi2->string_defs,
1928 	};
1929 	struct usb_gadget_strings *strings[] = {
1930 		&string_fn,
1931 		NULL,
1932 	};
1933 	int i, blk, status;
1934 
1935 	midi2->gadget = cdev->gadget;
1936 	midi2->operation_mode = MIDI_OP_MODE_UNSET;
1937 
1938 	status = f_midi2_create_card(midi2);
1939 	if (status < 0)
1940 		goto fail_register;
1941 
1942 	/* maybe allocate device-global string ID */
1943 	midi2->strings = usb_gstrings_attach(c->cdev, strings,
1944 					     midi2->total_blocks + 1);
1945 	if (IS_ERR(midi2->strings)) {
1946 		status = PTR_ERR(midi2->strings);
1947 		goto fail_string;
1948 	}
1949 
1950 	mutex_lock(&f_midi2_desc_mutex);
1951 	midi2_midi1_if_desc.iInterface = midi2->strings[STR_IFACE].id;
1952 	midi2_midi2_if_desc.iInterface = midi2->strings[STR_IFACE].id;
1953 	for (i = 0; i < midi2->num_eps; i++) {
1954 		ep = &midi2->midi2_eps[i];
1955 		for (blk = 0; blk < ep->num_blks; blk++)
1956 			ep->blks[blk].string_id =
1957 				midi2->strings[gtb_to_str_id(ep->blks[blk].gtb_id)].id;
1958 	}
1959 
1960 	midi2_midi2_if_desc.bNumEndpoints = midi2->num_eps * 2;
1961 
1962 	/* audio interface */
1963 	status = usb_interface_id(c, f);
1964 	if (status < 0)
1965 		goto fail;
1966 	midi2_audio_if_desc.bInterfaceNumber = status;
1967 
1968 	/* MIDI streaming */
1969 	status = usb_interface_id(c, f);
1970 	if (status < 0)
1971 		goto fail;
1972 	midi2->midi_if = status;
1973 	midi2_midi1_if_desc.bInterfaceNumber = status;
1974 	midi2_midi2_if_desc.bInterfaceNumber = status;
1975 	midi2_audio_class_desc.baInterfaceNr[0] = status;
1976 
1977 	/* allocate instance-specific endpoints */
1978 	if (midi2->midi2_eps[0].blks[0].info.direction != SNDRV_UMP_DIR_OUTPUT) {
1979 		status = f_midi2_init_ep(midi2, NULL, &midi2->midi1_ep_in,
1980 					 &midi2_midi1_ep_in_desc,
1981 					 f_midi2_midi1_ep_in_complete);
1982 		if (status)
1983 			goto fail;
1984 	}
1985 
1986 	if (midi2->midi2_eps[0].blks[0].info.direction != SNDRV_UMP_DIR_INPUT) {
1987 		status = f_midi2_init_ep(midi2, NULL, &midi2->midi1_ep_out,
1988 					 &midi2_midi1_ep_out_desc,
1989 					 f_midi2_midi1_ep_out_complete);
1990 		if (status)
1991 			goto fail;
1992 	}
1993 
1994 	for (i = 0; i < midi2->num_eps; i++) {
1995 		status = f_midi2_init_midi2_ep_in(midi2, i);
1996 		if (status)
1997 			goto fail;
1998 		status = f_midi2_init_midi2_ep_out(midi2, i);
1999 		if (status)
2000 			goto fail;
2001 	}
2002 
2003 	status = f_midi2_create_usb_configs(midi2, &config, USB_SPEED_FULL);
2004 	if (status < 0)
2005 		goto fail;
2006 	f->fs_descriptors = usb_copy_descriptors(config.list);
2007 	if (!f->fs_descriptors) {
2008 		status = -ENOMEM;
2009 		goto fail;
2010 	}
2011 	f_midi2_free_usb_configs(&config);
2012 
2013 	status = f_midi2_create_usb_configs(midi2, &config, USB_SPEED_HIGH);
2014 	if (status < 0)
2015 		goto fail;
2016 	f->hs_descriptors = usb_copy_descriptors(config.list);
2017 	if (!f->hs_descriptors) {
2018 		status = -ENOMEM;
2019 		goto fail;
2020 	}
2021 	f_midi2_free_usb_configs(&config);
2022 
2023 	status = f_midi2_create_usb_configs(midi2, &config, USB_SPEED_SUPER);
2024 	if (status < 0)
2025 		goto fail;
2026 	f->ss_descriptors = usb_copy_descriptors(config.list);
2027 	if (!f->ss_descriptors) {
2028 		status = -ENOMEM;
2029 		goto fail;
2030 	}
2031 	f_midi2_free_usb_configs(&config);
2032 
2033 	mutex_unlock(&f_midi2_desc_mutex);
2034 	return 0;
2035 
2036 fail:
2037 	f_midi2_free_usb_configs(&config);
2038 	mutex_unlock(&f_midi2_desc_mutex);
2039 	usb_free_all_descriptors(f);
2040 fail_string:
2041 	f_midi2_free_card(midi2);
2042 fail_register:
2043 	ERROR(midi2, "%s: can't bind, err %d\n", f->name, status);
2044 	return status;
2045 }
2046 
2047 /* gadget function unbind callback */
2048 static void f_midi2_unbind(struct usb_configuration *c, struct usb_function *f)
2049 {
2050 	struct f_midi2 *midi2 = func_to_midi2(f);
2051 	int i;
2052 
2053 	f_midi2_free_card(midi2);
2054 
2055 	f_midi2_free_ep(&midi2->midi1_ep_in);
2056 	f_midi2_free_ep(&midi2->midi1_ep_out);
2057 	for (i = 0; i < midi2->num_eps; i++) {
2058 		f_midi2_free_ep(&midi2->midi2_eps[i].ep_in);
2059 		f_midi2_free_ep(&midi2->midi2_eps[i].ep_out);
2060 	}
2061 
2062 	usb_free_all_descriptors(f);
2063 }
2064 
2065 /*
2066  * ConfigFS interface
2067  */
2068 
2069 /* type conversion helpers */
2070 static inline struct f_midi2_opts *to_f_midi2_opts(struct config_item *item)
2071 {
2072 	return container_of(to_config_group(item), struct f_midi2_opts,
2073 			    func_inst.group);
2074 }
2075 
2076 static inline struct f_midi2_ep_opts *
2077 to_f_midi2_ep_opts(struct config_item *item)
2078 {
2079 	return container_of(to_config_group(item), struct f_midi2_ep_opts,
2080 			    group);
2081 }
2082 
2083 static inline struct f_midi2_block_opts *
2084 to_f_midi2_block_opts(struct config_item *item)
2085 {
2086 	return container_of(to_config_group(item), struct f_midi2_block_opts,
2087 			    group);
2088 }
2089 
2090 /* trim the string to be usable for EP and FB name strings */
2091 static void make_name_string(char *s)
2092 {
2093 	char *p;
2094 
2095 	p = strchr(s, '\n');
2096 	if (p)
2097 		*p = 0;
2098 
2099 	p = s + strlen(s);
2100 	for (; p > s && isspace(*p); p--)
2101 		*p = 0;
2102 }
2103 
2104 /* configfs helpers: generic show/store for unisnged int */
2105 static ssize_t f_midi2_opts_uint_show(struct f_midi2_opts *opts,
2106 				      u32 val, const char *format, char *page)
2107 {
2108 	int result;
2109 
2110 	mutex_lock(&opts->lock);
2111 	result = sprintf(page, format, val);
2112 	mutex_unlock(&opts->lock);
2113 	return result;
2114 }
2115 
2116 static ssize_t f_midi2_opts_uint_store(struct f_midi2_opts *opts,
2117 				       u32 *valp, u32 minval, u32 maxval,
2118 				       const char *page, size_t len)
2119 {
2120 	int ret;
2121 	u32 val;
2122 
2123 	mutex_lock(&opts->lock);
2124 	if (opts->refcnt) {
2125 		ret = -EBUSY;
2126 		goto end;
2127 	}
2128 
2129 	ret = kstrtou32(page, 0, &val);
2130 	if (ret)
2131 		goto end;
2132 	if (val < minval || val > maxval) {
2133 		ret = -EINVAL;
2134 		goto end;
2135 	}
2136 
2137 	*valp = val;
2138 	ret = len;
2139 
2140 end:
2141 	mutex_unlock(&opts->lock);
2142 	return ret;
2143 }
2144 
2145 /* generic store for bool */
2146 static ssize_t f_midi2_opts_bool_store(struct f_midi2_opts *opts,
2147 				       bool *valp, const char *page, size_t len)
2148 {
2149 	int ret;
2150 	bool val;
2151 
2152 	mutex_lock(&opts->lock);
2153 	if (opts->refcnt) {
2154 		ret = -EBUSY;
2155 		goto end;
2156 	}
2157 
2158 	ret = kstrtobool(page, &val);
2159 	if (ret)
2160 		goto end;
2161 	*valp = val;
2162 	ret = len;
2163 
2164 end:
2165 	mutex_unlock(&opts->lock);
2166 	return ret;
2167 }
2168 
2169 /* generic show/store for string */
2170 static ssize_t f_midi2_opts_str_show(struct f_midi2_opts *opts,
2171 				     const char *str, char *page)
2172 {
2173 	int result = 0;
2174 
2175 	mutex_lock(&opts->lock);
2176 	if (str)
2177 		result = scnprintf(page, PAGE_SIZE, "%s\n", str);
2178 	mutex_unlock(&opts->lock);
2179 	return result;
2180 }
2181 
2182 static ssize_t f_midi2_opts_str_store(struct f_midi2_opts *opts,
2183 				      const char **strp, size_t maxlen,
2184 				      const char *page, size_t len)
2185 {
2186 	char *c;
2187 	int ret;
2188 
2189 	mutex_lock(&opts->lock);
2190 	if (opts->refcnt) {
2191 		ret = -EBUSY;
2192 		goto end;
2193 	}
2194 
2195 	c = kstrndup(page, min(len, maxlen), GFP_KERNEL);
2196 	if (!c) {
2197 		ret = -ENOMEM;
2198 		goto end;
2199 	}
2200 
2201 	kfree(*strp);
2202 	make_name_string(c);
2203 	*strp = c;
2204 	ret = len;
2205 
2206 end:
2207 	mutex_unlock(&opts->lock);
2208 	return ret;
2209 }
2210 
2211 /*
2212  * Definitions for UMP Block config
2213  */
2214 
2215 /* define an uint option for block */
2216 #define F_MIDI2_BLOCK_OPT(name, format, minval, maxval)			\
2217 static ssize_t f_midi2_block_opts_##name##_show(struct config_item *item,\
2218 					  char *page)			\
2219 {									\
2220 	struct f_midi2_block_opts *opts = to_f_midi2_block_opts(item);	\
2221 	return f_midi2_opts_uint_show(opts->ep->opts, opts->info.name,	\
2222 				      format "\n", page);		\
2223 }									\
2224 									\
2225 static ssize_t f_midi2_block_opts_##name##_store(struct config_item *item,\
2226 					 const char *page, size_t len)	\
2227 {									\
2228 	struct f_midi2_block_opts *opts = to_f_midi2_block_opts(item);	\
2229 	return f_midi2_opts_uint_store(opts->ep->opts, &opts->info.name,\
2230 				       minval, maxval, page, len);	\
2231 }									\
2232 									\
2233 CONFIGFS_ATTR(f_midi2_block_opts_, name)
2234 
2235 /* define a boolean option for block */
2236 #define F_MIDI2_BLOCK_BOOL_OPT(name)					\
2237 static ssize_t f_midi2_block_opts_##name##_show(struct config_item *item,\
2238 					  char *page)			\
2239 {									\
2240 	struct f_midi2_block_opts *opts = to_f_midi2_block_opts(item);	\
2241 	return f_midi2_opts_uint_show(opts->ep->opts, opts->info.name,	\
2242 				      "%u\n", page);			\
2243 }									\
2244 									\
2245 static ssize_t f_midi2_block_opts_##name##_store(struct config_item *item,\
2246 					 const char *page, size_t len)	\
2247 {									\
2248 	struct f_midi2_block_opts *opts = to_f_midi2_block_opts(item);	\
2249 	return f_midi2_opts_bool_store(opts->ep->opts, &opts->info.name,\
2250 				       page, len);			\
2251 }									\
2252 									\
2253 CONFIGFS_ATTR(f_midi2_block_opts_, name)
2254 
2255 F_MIDI2_BLOCK_OPT(direction, "0x%x", 1, 3);
2256 F_MIDI2_BLOCK_OPT(first_group, "0x%x", 0, 15);
2257 F_MIDI2_BLOCK_OPT(num_groups, "0x%x", 1, 16);
2258 F_MIDI2_BLOCK_OPT(midi1_first_group, "0x%x", 0, 15);
2259 F_MIDI2_BLOCK_OPT(midi1_num_groups, "0x%x", 0, 16);
2260 F_MIDI2_BLOCK_OPT(ui_hint, "0x%x", 0, 3);
2261 F_MIDI2_BLOCK_OPT(midi_ci_version, "%u", 0, 1);
2262 F_MIDI2_BLOCK_OPT(sysex8_streams, "%u", 0, 255);
2263 F_MIDI2_BLOCK_OPT(is_midi1, "%u", 0, 2);
2264 F_MIDI2_BLOCK_BOOL_OPT(active);
2265 
2266 static ssize_t f_midi2_block_opts_name_show(struct config_item *item,
2267 					    char *page)
2268 {
2269 	struct f_midi2_block_opts *opts = to_f_midi2_block_opts(item);
2270 
2271 	return f_midi2_opts_str_show(opts->ep->opts, opts->info.name, page);
2272 }
2273 
2274 static ssize_t f_midi2_block_opts_name_store(struct config_item *item,
2275 					     const char *page, size_t len)
2276 {
2277 	struct f_midi2_block_opts *opts = to_f_midi2_block_opts(item);
2278 
2279 	return f_midi2_opts_str_store(opts->ep->opts, &opts->info.name, 128,
2280 				      page, len);
2281 }
2282 
2283 CONFIGFS_ATTR(f_midi2_block_opts_, name);
2284 
2285 static struct configfs_attribute *f_midi2_block_attrs[] = {
2286 	&f_midi2_block_opts_attr_direction,
2287 	&f_midi2_block_opts_attr_first_group,
2288 	&f_midi2_block_opts_attr_num_groups,
2289 	&f_midi2_block_opts_attr_midi1_first_group,
2290 	&f_midi2_block_opts_attr_midi1_num_groups,
2291 	&f_midi2_block_opts_attr_ui_hint,
2292 	&f_midi2_block_opts_attr_midi_ci_version,
2293 	&f_midi2_block_opts_attr_sysex8_streams,
2294 	&f_midi2_block_opts_attr_is_midi1,
2295 	&f_midi2_block_opts_attr_active,
2296 	&f_midi2_block_opts_attr_name,
2297 	NULL,
2298 };
2299 
2300 static void f_midi2_block_opts_release(struct config_item *item)
2301 {
2302 	struct f_midi2_block_opts *opts = to_f_midi2_block_opts(item);
2303 
2304 	kfree(opts->info.name);
2305 	kfree(opts);
2306 }
2307 
2308 static struct configfs_item_operations f_midi2_block_item_ops = {
2309 	.release	= f_midi2_block_opts_release,
2310 };
2311 
2312 static const struct config_item_type f_midi2_block_type = {
2313 	.ct_item_ops	= &f_midi2_block_item_ops,
2314 	.ct_attrs	= f_midi2_block_attrs,
2315 	.ct_owner	= THIS_MODULE,
2316 };
2317 
2318 /* create a f_midi2_block_opts instance for the given block number */
2319 static int f_midi2_block_opts_create(struct f_midi2_ep_opts *ep_opts,
2320 				     unsigned int blk,
2321 				     struct f_midi2_block_opts **block_p)
2322 {
2323 	struct f_midi2_block_opts *block_opts;
2324 	int ret = 0;
2325 
2326 	mutex_lock(&ep_opts->opts->lock);
2327 	if (ep_opts->opts->refcnt || ep_opts->blks[blk]) {
2328 		ret = -EBUSY;
2329 		goto out;
2330 	}
2331 
2332 	block_opts = kzalloc(sizeof(*block_opts), GFP_KERNEL);
2333 	if (!block_opts) {
2334 		ret = -ENOMEM;
2335 		goto out;
2336 	}
2337 
2338 	block_opts->ep = ep_opts;
2339 	block_opts->id = blk;
2340 
2341 	/* set up the default values */
2342 	block_opts->info.direction = SNDRV_UMP_DIR_BIDIRECTION;
2343 	block_opts->info.first_group = 0;
2344 	block_opts->info.num_groups = 1;
2345 	block_opts->info.ui_hint = SNDRV_UMP_BLOCK_UI_HINT_BOTH;
2346 	block_opts->info.active = 1;
2347 
2348 	ep_opts->blks[blk] = block_opts;
2349 	*block_p = block_opts;
2350 
2351  out:
2352 	mutex_unlock(&ep_opts->opts->lock);
2353 	return ret;
2354 }
2355 
2356 /* make_group callback for a block */
2357 static struct config_group *
2358 f_midi2_opts_block_make(struct config_group *group, const char *name)
2359 {
2360 	struct f_midi2_ep_opts *ep_opts;
2361 	struct f_midi2_block_opts *block_opts;
2362 	unsigned int blk;
2363 	int ret;
2364 
2365 	if (strncmp(name, "block.", 6))
2366 		return ERR_PTR(-EINVAL);
2367 	ret = kstrtouint(name + 6, 10, &blk);
2368 	if (ret)
2369 		return ERR_PTR(ret);
2370 
2371 	ep_opts = to_f_midi2_ep_opts(&group->cg_item);
2372 
2373 	if (blk >= SNDRV_UMP_MAX_BLOCKS)
2374 		return ERR_PTR(-EINVAL);
2375 	if (ep_opts->blks[blk])
2376 		return ERR_PTR(-EBUSY);
2377 	ret = f_midi2_block_opts_create(ep_opts, blk, &block_opts);
2378 	if (ret)
2379 		return ERR_PTR(ret);
2380 
2381 	config_group_init_type_name(&block_opts->group, name,
2382 				    &f_midi2_block_type);
2383 	return &block_opts->group;
2384 }
2385 
2386 /* drop_item callback for a block */
2387 static void
2388 f_midi2_opts_block_drop(struct config_group *group, struct config_item *item)
2389 {
2390 	struct f_midi2_block_opts *block_opts = to_f_midi2_block_opts(item);
2391 
2392 	mutex_lock(&block_opts->ep->opts->lock);
2393 	block_opts->ep->blks[block_opts->id] = NULL;
2394 	mutex_unlock(&block_opts->ep->opts->lock);
2395 	config_item_put(item);
2396 }
2397 
2398 /*
2399  * Definitions for UMP Endpoint config
2400  */
2401 
2402 /* define an uint option for EP */
2403 #define F_MIDI2_EP_OPT(name, format, minval, maxval)			\
2404 static ssize_t f_midi2_ep_opts_##name##_show(struct config_item *item,	\
2405 					     char *page)		\
2406 {									\
2407 	struct f_midi2_ep_opts *opts = to_f_midi2_ep_opts(item);	\
2408 	return f_midi2_opts_uint_show(opts->opts, opts->info.name,	\
2409 				      format "\n", page);		\
2410 }									\
2411 									\
2412 static ssize_t f_midi2_ep_opts_##name##_store(struct config_item *item,	\
2413 					   const char *page, size_t len)\
2414 {									\
2415 	struct f_midi2_ep_opts *opts = to_f_midi2_ep_opts(item);	\
2416 	return f_midi2_opts_uint_store(opts->opts, &opts->info.name,	\
2417 				       minval, maxval, page, len);	\
2418 }									\
2419 									\
2420 CONFIGFS_ATTR(f_midi2_ep_opts_, name)
2421 
2422 /* define a string option for EP */
2423 #define F_MIDI2_EP_STR_OPT(name, maxlen)				\
2424 static ssize_t f_midi2_ep_opts_##name##_show(struct config_item *item,	\
2425 					     char *page)		\
2426 {									\
2427 	struct f_midi2_ep_opts *opts = to_f_midi2_ep_opts(item);	\
2428 	return f_midi2_opts_str_show(opts->opts, opts->info.name, page);\
2429 }									\
2430 									\
2431 static ssize_t f_midi2_ep_opts_##name##_store(struct config_item *item,	\
2432 					 const char *page, size_t len)	\
2433 {									\
2434 	struct f_midi2_ep_opts *opts = to_f_midi2_ep_opts(item);	\
2435 	return f_midi2_opts_str_store(opts->opts, &opts->info.name, maxlen,\
2436 				      page, len);			\
2437 }									\
2438 									\
2439 CONFIGFS_ATTR(f_midi2_ep_opts_, name)
2440 
2441 F_MIDI2_EP_OPT(protocol, "0x%x", 1, 2);
2442 F_MIDI2_EP_OPT(protocol_caps, "0x%x", 1, 3);
2443 F_MIDI2_EP_OPT(manufacturer, "0x%x", 0, 0xffffff);
2444 F_MIDI2_EP_OPT(family, "0x%x", 0, 0xffff);
2445 F_MIDI2_EP_OPT(model, "0x%x", 0, 0xffff);
2446 F_MIDI2_EP_OPT(sw_revision, "0x%x", 0, 0xffffffff);
2447 F_MIDI2_EP_STR_OPT(ep_name, 128);
2448 F_MIDI2_EP_STR_OPT(product_id, 128);
2449 
2450 static struct configfs_attribute *f_midi2_ep_attrs[] = {
2451 	&f_midi2_ep_opts_attr_protocol,
2452 	&f_midi2_ep_opts_attr_protocol_caps,
2453 	&f_midi2_ep_opts_attr_ep_name,
2454 	&f_midi2_ep_opts_attr_product_id,
2455 	&f_midi2_ep_opts_attr_manufacturer,
2456 	&f_midi2_ep_opts_attr_family,
2457 	&f_midi2_ep_opts_attr_model,
2458 	&f_midi2_ep_opts_attr_sw_revision,
2459 	NULL,
2460 };
2461 
2462 static void f_midi2_ep_opts_release(struct config_item *item)
2463 {
2464 	struct f_midi2_ep_opts *opts = to_f_midi2_ep_opts(item);
2465 
2466 	kfree(opts->info.ep_name);
2467 	kfree(opts->info.product_id);
2468 	kfree(opts);
2469 }
2470 
2471 static struct configfs_item_operations f_midi2_ep_item_ops = {
2472 	.release	= f_midi2_ep_opts_release,
2473 };
2474 
2475 static struct configfs_group_operations f_midi2_ep_group_ops = {
2476 	.make_group	= f_midi2_opts_block_make,
2477 	.drop_item	= f_midi2_opts_block_drop,
2478 };
2479 
2480 static const struct config_item_type f_midi2_ep_type = {
2481 	.ct_item_ops	= &f_midi2_ep_item_ops,
2482 	.ct_group_ops	= &f_midi2_ep_group_ops,
2483 	.ct_attrs	= f_midi2_ep_attrs,
2484 	.ct_owner	= THIS_MODULE,
2485 };
2486 
2487 /* create a f_midi2_ep_opts instance */
2488 static int f_midi2_ep_opts_create(struct f_midi2_opts *opts,
2489 				  unsigned int index,
2490 				  struct f_midi2_ep_opts **ep_p)
2491 {
2492 	struct f_midi2_ep_opts *ep_opts;
2493 
2494 	ep_opts = kzalloc(sizeof(*ep_opts), GFP_KERNEL);
2495 	if (!ep_opts)
2496 		return -ENOMEM;
2497 
2498 	ep_opts->opts = opts;
2499 	ep_opts->index = index;
2500 
2501 	/* set up the default values */
2502 	ep_opts->info.protocol = 2;
2503 	ep_opts->info.protocol_caps = 3;
2504 
2505 	opts->eps[index] = ep_opts;
2506 	*ep_p = ep_opts;
2507 	return 0;
2508 }
2509 
2510 /* make_group callback for an EP */
2511 static struct config_group *
2512 f_midi2_opts_ep_make(struct config_group *group, const char *name)
2513 {
2514 	struct f_midi2_opts *opts;
2515 	struct f_midi2_ep_opts *ep_opts;
2516 	unsigned int index;
2517 	int ret;
2518 
2519 	if (strncmp(name, "ep.", 3))
2520 		return ERR_PTR(-EINVAL);
2521 	ret = kstrtouint(name + 3, 10, &index);
2522 	if (ret)
2523 		return ERR_PTR(ret);
2524 
2525 	opts = to_f_midi2_opts(&group->cg_item);
2526 	if (index >= MAX_UMP_EPS)
2527 		return ERR_PTR(-EINVAL);
2528 	if (opts->eps[index])
2529 		return ERR_PTR(-EBUSY);
2530 	ret = f_midi2_ep_opts_create(opts, index, &ep_opts);
2531 	if (ret)
2532 		return ERR_PTR(ret);
2533 
2534 	config_group_init_type_name(&ep_opts->group, name, &f_midi2_ep_type);
2535 	return &ep_opts->group;
2536 }
2537 
2538 /* drop_item callback for an EP */
2539 static void
2540 f_midi2_opts_ep_drop(struct config_group *group, struct config_item *item)
2541 {
2542 	struct f_midi2_ep_opts *ep_opts = to_f_midi2_ep_opts(item);
2543 
2544 	mutex_lock(&ep_opts->opts->lock);
2545 	ep_opts->opts->eps[ep_opts->index] = NULL;
2546 	mutex_unlock(&ep_opts->opts->lock);
2547 	config_item_put(item);
2548 }
2549 
2550 /*
2551  * Definitions for card config
2552  */
2553 
2554 /* define a bool option for card */
2555 #define F_MIDI2_BOOL_OPT(name)						\
2556 static ssize_t f_midi2_opts_##name##_show(struct config_item *item,	\
2557 					  char *page)			\
2558 {									\
2559 	struct f_midi2_opts *opts = to_f_midi2_opts(item);		\
2560 	return f_midi2_opts_uint_show(opts, opts->info.name,		\
2561 				      "%u\n", page);			\
2562 }									\
2563 									\
2564 static ssize_t f_midi2_opts_##name##_store(struct config_item *item,	\
2565 					 const char *page, size_t len)	\
2566 {									\
2567 	struct f_midi2_opts *opts = to_f_midi2_opts(item);		\
2568 	return f_midi2_opts_bool_store(opts, &opts->info.name,		\
2569 				       page, len);			\
2570 }									\
2571 									\
2572 CONFIGFS_ATTR(f_midi2_opts_, name)
2573 
2574 F_MIDI2_BOOL_OPT(process_ump);
2575 F_MIDI2_BOOL_OPT(static_block);
2576 
2577 static ssize_t f_midi2_opts_iface_name_show(struct config_item *item,
2578 					    char *page)
2579 {
2580 	struct f_midi2_opts *opts = to_f_midi2_opts(item);
2581 
2582 	return f_midi2_opts_str_show(opts, opts->info.iface_name, page);
2583 }
2584 
2585 static ssize_t f_midi2_opts_iface_name_store(struct config_item *item,
2586 					     const char *page, size_t len)
2587 {
2588 	struct f_midi2_opts *opts = to_f_midi2_opts(item);
2589 
2590 	return f_midi2_opts_str_store(opts, &opts->info.iface_name, 128,
2591 				      page, len);
2592 }
2593 
2594 CONFIGFS_ATTR(f_midi2_opts_, iface_name);
2595 
2596 static struct configfs_attribute *f_midi2_attrs[] = {
2597 	&f_midi2_opts_attr_process_ump,
2598 	&f_midi2_opts_attr_static_block,
2599 	&f_midi2_opts_attr_iface_name,
2600 	NULL
2601 };
2602 
2603 static void f_midi2_opts_release(struct config_item *item)
2604 {
2605 	struct f_midi2_opts *opts = to_f_midi2_opts(item);
2606 
2607 	usb_put_function_instance(&opts->func_inst);
2608 }
2609 
2610 static struct configfs_item_operations f_midi2_item_ops = {
2611 	.release	= f_midi2_opts_release,
2612 };
2613 
2614 static struct configfs_group_operations f_midi2_group_ops = {
2615 	.make_group	= f_midi2_opts_ep_make,
2616 	.drop_item	= f_midi2_opts_ep_drop,
2617 };
2618 
2619 static const struct config_item_type f_midi2_func_type = {
2620 	.ct_item_ops	= &f_midi2_item_ops,
2621 	.ct_group_ops	= &f_midi2_group_ops,
2622 	.ct_attrs	= f_midi2_attrs,
2623 	.ct_owner	= THIS_MODULE,
2624 };
2625 
2626 static void f_midi2_free_inst(struct usb_function_instance *f)
2627 {
2628 	struct f_midi2_opts *opts;
2629 
2630 	opts = container_of(f, struct f_midi2_opts, func_inst);
2631 
2632 	kfree(opts->info.iface_name);
2633 	kfree(opts);
2634 }
2635 
2636 /* gadget alloc_inst */
2637 static struct usb_function_instance *f_midi2_alloc_inst(void)
2638 {
2639 	struct f_midi2_opts *opts;
2640 	struct f_midi2_ep_opts *ep_opts;
2641 	struct f_midi2_block_opts *block_opts;
2642 	int ret;
2643 
2644 	opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2645 	if (!opts)
2646 		return ERR_PTR(-ENOMEM);
2647 
2648 	mutex_init(&opts->lock);
2649 	opts->func_inst.free_func_inst = f_midi2_free_inst;
2650 	opts->info.process_ump = true;
2651 	opts->info.static_block = true;
2652 	opts->info.num_reqs = 32;
2653 	opts->info.req_buf_size = 512;
2654 
2655 	/* create the default ep */
2656 	ret = f_midi2_ep_opts_create(opts, 0, &ep_opts);
2657 	if (ret) {
2658 		kfree(opts);
2659 		return ERR_PTR(ret);
2660 	}
2661 
2662 	/* create the default block */
2663 	ret = f_midi2_block_opts_create(ep_opts, 0, &block_opts);
2664 	if (ret) {
2665 		kfree(ep_opts);
2666 		kfree(opts);
2667 		return ERR_PTR(ret);
2668 	}
2669 
2670 	/* set up the default MIDI1 (that is mandatory) */
2671 	block_opts->info.midi1_num_groups = 1;
2672 
2673 	config_group_init_type_name(&opts->func_inst.group, "",
2674 				    &f_midi2_func_type);
2675 
2676 	config_group_init_type_name(&ep_opts->group, "ep.0",
2677 				    &f_midi2_ep_type);
2678 	configfs_add_default_group(&ep_opts->group, &opts->func_inst.group);
2679 
2680 	config_group_init_type_name(&block_opts->group, "block.0",
2681 				    &f_midi2_block_type);
2682 	configfs_add_default_group(&block_opts->group, &ep_opts->group);
2683 
2684 	return &opts->func_inst;
2685 }
2686 
2687 static void do_f_midi2_free(struct f_midi2 *midi2, struct f_midi2_opts *opts)
2688 {
2689 	mutex_lock(&opts->lock);
2690 	--opts->refcnt;
2691 	mutex_unlock(&opts->lock);
2692 	kfree(midi2->string_defs);
2693 	kfree(midi2);
2694 }
2695 
2696 static void f_midi2_free(struct usb_function *f)
2697 {
2698 	do_f_midi2_free(func_to_midi2(f),
2699 			container_of(f->fi, struct f_midi2_opts, func_inst));
2700 }
2701 
2702 /* verify the parameters set up via configfs;
2703  * return the number of EPs or a negative error
2704  */
2705 static int verify_parameters(struct f_midi2_opts *opts)
2706 {
2707 	int i, j, num_eps, num_blks;
2708 	struct f_midi2_ep_info *ep;
2709 	struct f_midi2_block_info *bp;
2710 
2711 	for (num_eps = 0; num_eps < MAX_UMP_EPS && opts->eps[num_eps];
2712 	     num_eps++)
2713 		;
2714 	if (!num_eps) {
2715 		pr_err("f_midi2: No EP is defined\n");
2716 		return -EINVAL;
2717 	}
2718 
2719 	num_blks = 0;
2720 	for (i = 0; i < num_eps; i++) {
2721 		ep = &opts->eps[i]->info;
2722 		if (!(ep->protocol_caps & ep->protocol)) {
2723 			pr_err("f_midi2: Invalid protocol 0x%x (caps 0x%x) for EP %d\n",
2724 			       ep->protocol, ep->protocol_caps, i);
2725 			return -EINVAL;
2726 		}
2727 
2728 		for (j = 0; j < SNDRV_UMP_MAX_BLOCKS && opts->eps[i]->blks[j];
2729 		     j++, num_blks++) {
2730 			bp = &opts->eps[i]->blks[j]->info;
2731 			if (bp->first_group + bp->num_groups > SNDRV_UMP_MAX_GROUPS) {
2732 				pr_err("f_midi2: Invalid group definitions for block %d:%d\n",
2733 				       i, j);
2734 				return -EINVAL;
2735 			}
2736 
2737 			if (bp->midi1_num_groups) {
2738 				if (bp->midi1_first_group < bp->first_group ||
2739 				    bp->midi1_first_group + bp->midi1_num_groups >
2740 				    bp->first_group + bp->num_groups) {
2741 					pr_err("f_midi2: Invalid MIDI1 group definitions for block %d:%d\n",
2742 					       i, j);
2743 					return -EINVAL;
2744 				}
2745 			}
2746 		}
2747 	}
2748 	if (!num_blks) {
2749 		pr_err("f_midi2: No block is defined\n");
2750 		return -EINVAL;
2751 	}
2752 
2753 	return num_eps;
2754 }
2755 
2756 /* fill mapping between MIDI 1.0 cable and UMP EP/group */
2757 static void fill_midi1_cable_mapping(struct f_midi2 *midi2,
2758 				     struct f_midi2_ep *ep,
2759 				     int blk)
2760 {
2761 	const struct f_midi2_block_info *binfo = &ep->blks[blk].info;
2762 	struct midi1_cable_mapping *map;
2763 	int i, group;
2764 
2765 	if (!binfo->midi1_num_groups)
2766 		return;
2767 	if (binfo->direction != SNDRV_UMP_DIR_OUTPUT) {
2768 		group = binfo->midi1_first_group;
2769 		map = midi2->in_cable_mapping + midi2->num_midi1_in;
2770 		for (i = 0; i < binfo->midi1_num_groups; i++, group++, map++) {
2771 			if (midi2->num_midi1_in >= MAX_CABLES)
2772 				break;
2773 			map->ep = ep;
2774 			map->block = blk;
2775 			map->group = group;
2776 			midi2->num_midi1_in++;
2777 			/* store 1-based cable number */
2778 			ep->in_group_to_cable[group] = midi2->num_midi1_in;
2779 		}
2780 	}
2781 
2782 	if (binfo->direction != SNDRV_UMP_DIR_INPUT) {
2783 		group = binfo->midi1_first_group;
2784 		map = midi2->out_cable_mapping + midi2->num_midi1_out;
2785 		for (i = 0; i < binfo->midi1_num_groups; i++, group++, map++) {
2786 			if (midi2->num_midi1_out >= MAX_CABLES)
2787 				break;
2788 			map->ep = ep;
2789 			map->block = blk;
2790 			map->group = group;
2791 			midi2->num_midi1_out++;
2792 		}
2793 	}
2794 }
2795 
2796 /* gadget alloc callback */
2797 static struct usb_function *f_midi2_alloc(struct usb_function_instance *fi)
2798 {
2799 	struct f_midi2 *midi2;
2800 	struct f_midi2_opts *opts;
2801 	struct f_midi2_ep *ep;
2802 	struct f_midi2_block *bp;
2803 	int i, num_eps, blk;
2804 
2805 	midi2 = kzalloc(sizeof(*midi2), GFP_KERNEL);
2806 	if (!midi2)
2807 		return ERR_PTR(-ENOMEM);
2808 
2809 	opts = container_of(fi, struct f_midi2_opts, func_inst);
2810 	mutex_lock(&opts->lock);
2811 	num_eps = verify_parameters(opts);
2812 	if (num_eps < 0) {
2813 		mutex_unlock(&opts->lock);
2814 		kfree(midi2);
2815 		return ERR_PTR(num_eps);
2816 	}
2817 	++opts->refcnt;
2818 	mutex_unlock(&opts->lock);
2819 
2820 	spin_lock_init(&midi2->queue_lock);
2821 
2822 	midi2->func.name = "midi2_func";
2823 	midi2->func.bind = f_midi2_bind;
2824 	midi2->func.unbind = f_midi2_unbind;
2825 	midi2->func.get_alt = f_midi2_get_alt;
2826 	midi2->func.set_alt = f_midi2_set_alt;
2827 	midi2->func.setup = f_midi2_setup;
2828 	midi2->func.disable = f_midi2_disable;
2829 	midi2->func.free_func = f_midi2_free;
2830 
2831 	midi2->info = opts->info;
2832 	midi2->num_eps = num_eps;
2833 
2834 	for (i = 0; i < num_eps; i++) {
2835 		ep = &midi2->midi2_eps[i];
2836 		ep->info = opts->eps[i]->info;
2837 		ep->card = midi2;
2838 		for (blk = 0; blk < SNDRV_UMP_MAX_BLOCKS &&
2839 			     opts->eps[i]->blks[blk]; blk++) {
2840 			bp = &ep->blks[blk];
2841 			ep->num_blks++;
2842 			bp->info = opts->eps[i]->blks[blk]->info;
2843 			bp->gtb_id = ++midi2->total_blocks;
2844 		}
2845 	}
2846 
2847 	midi2->string_defs = kcalloc(midi2->total_blocks + 1,
2848 				     sizeof(*midi2->string_defs), GFP_KERNEL);
2849 	if (!midi2->string_defs) {
2850 		do_f_midi2_free(midi2, opts);
2851 		return ERR_PTR(-ENOMEM);
2852 	}
2853 
2854 	if (opts->info.iface_name && *opts->info.iface_name)
2855 		midi2->string_defs[STR_IFACE].s = opts->info.iface_name;
2856 	else
2857 		midi2->string_defs[STR_IFACE].s = ump_ep_name(&midi2->midi2_eps[0]);
2858 
2859 	for (i = 0; i < midi2->num_eps; i++) {
2860 		ep = &midi2->midi2_eps[i];
2861 		for (blk = 0; blk < ep->num_blks; blk++) {
2862 			bp = &ep->blks[blk];
2863 			midi2->string_defs[gtb_to_str_id(bp->gtb_id)].s =
2864 				ump_fb_name(&bp->info);
2865 
2866 			fill_midi1_cable_mapping(midi2, ep, blk);
2867 		}
2868 	}
2869 
2870 	if (!midi2->num_midi1_in && !midi2->num_midi1_out) {
2871 		pr_err("f_midi2: MIDI1 definition is missing\n");
2872 		do_f_midi2_free(midi2, opts);
2873 		return ERR_PTR(-EINVAL);
2874 	}
2875 
2876 	return &midi2->func;
2877 }
2878 
2879 DECLARE_USB_FUNCTION_INIT(midi2, f_midi2_alloc_inst, f_midi2_alloc);
2880 
2881 MODULE_DESCRIPTION("USB MIDI 2.0 class function driver");
2882 MODULE_LICENSE("GPL");
2883