1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * f_midi.c -- USB MIDI class function driver
4 *
5 * Copyright (C) 2006 Thumtronics Pty Ltd.
6 * Developed for Thumtronics by Grey Innovation
7 * Ben Williamson <ben.williamson@greyinnovation.com>
8 *
9 * Rewritten for the composite framework
10 * Copyright (C) 2011 Daniel Mack <zonque@gmail.com>
11 *
12 * Based on drivers/usb/gadget/f_audio.c,
13 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
14 * Copyright (C) 2008 Analog Devices, Inc
15 *
16 * and drivers/usb/gadget/midi.c,
17 * Copyright (C) 2006 Thumtronics Pty Ltd.
18 * Ben Williamson <ben.williamson@greyinnovation.com>
19 */
20
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/slab.h>
24 #include <linux/device.h>
25 #include <linux/kfifo.h>
26 #include <linux/spinlock.h>
27
28 #include <sound/core.h>
29 #include <sound/initval.h>
30 #include <sound/rawmidi.h>
31
32 #include <linux/usb/ch9.h>
33 #include <linux/usb/func_utils.h>
34 #include <linux/usb/gadget.h>
35 #include <linux/usb/audio.h>
36 #include <linux/usb/midi.h>
37
38 #include "u_midi.h"
39
40 MODULE_AUTHOR("Ben Williamson");
41 MODULE_DESCRIPTION("USB MIDI class function driver");
42 MODULE_LICENSE("GPL v2");
43
44 static const char f_midi_shortname[] = "f_midi";
45 static const char f_midi_longname[] = "MIDI Gadget";
46
47 /*
48 * We can only handle 16 cables on one single endpoint, as cable numbers are
49 * stored in 4-bit fields. And as the interface currently only holds one
50 * single endpoint, this is the maximum number of ports we can allow.
51 */
52 #define MAX_PORTS 16
53
54 /* MIDI message states */
55 enum {
56 STATE_INITIAL = 0, /* pseudo state */
57 STATE_1PARAM,
58 STATE_2PARAM_1,
59 STATE_2PARAM_2,
60 STATE_SYSEX_0,
61 STATE_SYSEX_1,
62 STATE_SYSEX_2,
63 STATE_REAL_TIME,
64 STATE_FINISHED, /* pseudo state */
65 };
66
67 /*
68 * This is a gadget, and the IN/OUT naming is from the host's perspective.
69 * USB -> OUT endpoint -> rawmidi
70 * USB <- IN endpoint <- rawmidi
71 */
72 struct gmidi_in_port {
73 struct snd_rawmidi_substream *substream;
74 int active;
75 uint8_t cable;
76 uint8_t state;
77 uint8_t data[2];
78 };
79
80 struct f_midi {
81 struct usb_function func;
82 struct usb_gadget *gadget;
83 struct usb_ep *in_ep, *out_ep;
84 struct snd_card *card;
85 struct snd_rawmidi *rmidi;
86 u8 ms_id;
87
88 struct snd_rawmidi_substream *out_substream[MAX_PORTS];
89
90 unsigned long out_triggered;
91 struct work_struct work;
92 unsigned int in_ports;
93 unsigned int out_ports;
94 int index;
95 char *id;
96 unsigned int buflen, qlen;
97 /* This fifo is used as a buffer ring for pre-allocated IN usb_requests */
98 DECLARE_KFIFO_PTR(in_req_fifo, struct usb_request *);
99 spinlock_t transmit_lock;
100 unsigned int in_last_port;
101 unsigned char free_ref;
102
103 struct gmidi_in_port in_ports_array[] __counted_by(in_ports);
104 };
105
func_to_midi(struct usb_function * f)106 static inline struct f_midi *func_to_midi(struct usb_function *f)
107 {
108 return container_of(f, struct f_midi, func);
109 }
110
111 static void f_midi_transmit(struct f_midi *midi);
112 static void f_midi_rmidi_free(struct snd_rawmidi *rmidi);
113 static void f_midi_free_inst(struct usb_function_instance *f);
114
115 DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
116 DECLARE_USB_MIDI_OUT_JACK_DESCRIPTOR(1);
117 DECLARE_USB_MS_ENDPOINT_DESCRIPTOR(16);
118
119 /* B.3.1 Standard AC Interface Descriptor */
120 static struct usb_interface_descriptor ac_interface_desc = {
121 .bLength = USB_DT_INTERFACE_SIZE,
122 .bDescriptorType = USB_DT_INTERFACE,
123 /* .bInterfaceNumber = DYNAMIC */
124 /* .bNumEndpoints = DYNAMIC */
125 .bInterfaceClass = USB_CLASS_AUDIO,
126 .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
127 /* .iInterface = DYNAMIC */
128 };
129
130 /* B.3.2 Class-Specific AC Interface Descriptor */
131 static struct uac1_ac_header_descriptor_1 ac_header_desc = {
132 .bLength = UAC_DT_AC_HEADER_SIZE(1),
133 .bDescriptorType = USB_DT_CS_INTERFACE,
134 .bDescriptorSubtype = USB_MS_HEADER,
135 .bcdADC = cpu_to_le16(0x0100),
136 .wTotalLength = cpu_to_le16(UAC_DT_AC_HEADER_SIZE(1)),
137 .bInCollection = 1,
138 /* .baInterfaceNr = DYNAMIC */
139 };
140
141 /* B.4.1 Standard MS Interface Descriptor */
142 static struct usb_interface_descriptor ms_interface_desc = {
143 .bLength = USB_DT_INTERFACE_SIZE,
144 .bDescriptorType = USB_DT_INTERFACE,
145 /* .bInterfaceNumber = DYNAMIC */
146 .bNumEndpoints = 2,
147 .bInterfaceClass = USB_CLASS_AUDIO,
148 .bInterfaceSubClass = USB_SUBCLASS_MIDISTREAMING,
149 /* .iInterface = DYNAMIC */
150 };
151
152 /* B.4.2 Class-Specific MS Interface Descriptor */
153 static struct usb_ms_header_descriptor ms_header_desc = {
154 .bLength = USB_DT_MS_HEADER_SIZE,
155 .bDescriptorType = USB_DT_CS_INTERFACE,
156 .bDescriptorSubtype = USB_MS_HEADER,
157 .bcdMSC = cpu_to_le16(0x0100),
158 /* .wTotalLength = DYNAMIC */
159 };
160
161 /* B.5.1 Standard Bulk OUT Endpoint Descriptor */
162 static struct usb_endpoint_descriptor bulk_out_desc = {
163 .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
164 .bDescriptorType = USB_DT_ENDPOINT,
165 .bEndpointAddress = USB_DIR_OUT,
166 .bmAttributes = USB_ENDPOINT_XFER_BULK,
167 };
168
169 static struct usb_ss_ep_comp_descriptor bulk_out_ss_comp_desc = {
170 .bLength = sizeof(bulk_out_ss_comp_desc),
171 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
172 /* .bMaxBurst = 0, */
173 /* .bmAttributes = 0, */
174 };
175
176 /* B.5.2 Class-specific MS Bulk OUT Endpoint Descriptor */
177 static struct usb_ms_endpoint_descriptor_16 ms_out_desc = {
178 /* .bLength = DYNAMIC */
179 .bDescriptorType = USB_DT_CS_ENDPOINT,
180 .bDescriptorSubtype = USB_MS_GENERAL,
181 /* .bNumEmbMIDIJack = DYNAMIC */
182 /* .baAssocJackID = DYNAMIC */
183 };
184
185 /* B.6.1 Standard Bulk IN Endpoint Descriptor */
186 static struct usb_endpoint_descriptor bulk_in_desc = {
187 .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
188 .bDescriptorType = USB_DT_ENDPOINT,
189 .bEndpointAddress = USB_DIR_IN,
190 .bmAttributes = USB_ENDPOINT_XFER_BULK,
191 };
192
193 static struct usb_ss_ep_comp_descriptor bulk_in_ss_comp_desc = {
194 .bLength = sizeof(bulk_in_ss_comp_desc),
195 .bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
196 /* .bMaxBurst = 0, */
197 /* .bmAttributes = 0, */
198 };
199
200 /* B.6.2 Class-specific MS Bulk IN Endpoint Descriptor */
201 static struct usb_ms_endpoint_descriptor_16 ms_in_desc = {
202 /* .bLength = DYNAMIC */
203 .bDescriptorType = USB_DT_CS_ENDPOINT,
204 .bDescriptorSubtype = USB_MS_GENERAL,
205 /* .bNumEmbMIDIJack = DYNAMIC */
206 /* .baAssocJackID = DYNAMIC */
207 };
208
209 /* string IDs are assigned dynamically */
210
211 #define STRING_FUNC_IDX 0
212
213 static struct usb_string midi_string_defs[] = {
214 [STRING_FUNC_IDX].s = "MIDI function",
215 { } /* end of list */
216 };
217
218 static struct usb_gadget_strings midi_stringtab = {
219 .language = 0x0409, /* en-us */
220 .strings = midi_string_defs,
221 };
222
223 static struct usb_gadget_strings *midi_strings[] = {
224 &midi_stringtab,
225 NULL,
226 };
227
midi_alloc_ep_req(struct usb_ep * ep,unsigned length)228 static inline struct usb_request *midi_alloc_ep_req(struct usb_ep *ep,
229 unsigned length)
230 {
231 return alloc_ep_req(ep, length);
232 }
233
234 static const uint8_t f_midi_cin_length[] = {
235 0, 0, 2, 3, 3, 1, 2, 3, 3, 3, 3, 3, 2, 2, 3, 1
236 };
237
238 /*
239 * Receives a chunk of MIDI data.
240 */
f_midi_read_data(struct usb_ep * ep,int cable,uint8_t * data,int length)241 static void f_midi_read_data(struct usb_ep *ep, int cable,
242 uint8_t *data, int length)
243 {
244 struct f_midi *midi = ep->driver_data;
245 struct snd_rawmidi_substream *substream = midi->out_substream[cable];
246
247 if (!substream)
248 /* Nobody is listening - throw it on the floor. */
249 return;
250
251 if (!test_bit(cable, &midi->out_triggered))
252 return;
253
254 snd_rawmidi_receive(substream, data, length);
255 }
256
f_midi_handle_out_data(struct usb_ep * ep,struct usb_request * req)257 static void f_midi_handle_out_data(struct usb_ep *ep, struct usb_request *req)
258 {
259 unsigned int i;
260 u8 *buf = req->buf;
261
262 for (i = 0; i + 3 < req->actual; i += 4)
263 if (buf[i] != 0) {
264 int cable = buf[i] >> 4;
265 int length = f_midi_cin_length[buf[i] & 0x0f];
266 f_midi_read_data(ep, cable, &buf[i + 1], length);
267 }
268 }
269
270 static void
f_midi_complete(struct usb_ep * ep,struct usb_request * req)271 f_midi_complete(struct usb_ep *ep, struct usb_request *req)
272 {
273 struct f_midi *midi = ep->driver_data;
274 struct usb_composite_dev *cdev = midi->func.config->cdev;
275 int status = req->status;
276
277 switch (status) {
278 case 0: /* normal completion */
279 if (ep == midi->out_ep) {
280 /* We received stuff. req is queued again, below */
281 f_midi_handle_out_data(ep, req);
282 } else if (ep == midi->in_ep) {
283 /* Our transmit completed. See if there's more to go.
284 * f_midi_transmit eats req, don't queue it again. */
285 req->length = 0;
286 f_midi_transmit(midi);
287 return;
288 }
289 break;
290
291 /* this endpoint is normally active while we're configured */
292 case -ECONNABORTED: /* hardware forced ep reset */
293 case -ECONNRESET: /* request dequeued */
294 case -ESHUTDOWN: /* disconnect from host */
295 VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
296 req->actual, req->length);
297 if (ep == midi->out_ep) {
298 f_midi_handle_out_data(ep, req);
299 /* We don't need to free IN requests because it's handled
300 * by the midi->in_req_fifo. */
301 free_ep_req(ep, req);
302 }
303 return;
304
305 case -EOVERFLOW: /* buffer overrun on read means that
306 * we didn't provide a big enough buffer.
307 */
308 default:
309 DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
310 status, req->actual, req->length);
311 break;
312 case -EREMOTEIO: /* short read */
313 break;
314 }
315
316 status = usb_ep_queue(ep, req, GFP_ATOMIC);
317 if (status) {
318 ERROR(cdev, "kill %s: resubmit %d bytes --> %d\n",
319 ep->name, req->length, status);
320 usb_ep_set_halt(ep);
321 /* FIXME recover later ... somehow */
322 }
323 }
324
f_midi_drop_out_substreams(struct f_midi * midi)325 static void f_midi_drop_out_substreams(struct f_midi *midi)
326 {
327 unsigned int i;
328
329 for (i = 0; i < midi->in_ports; i++) {
330 struct gmidi_in_port *port = midi->in_ports_array + i;
331 struct snd_rawmidi_substream *substream = port->substream;
332
333 if (port->active && substream)
334 snd_rawmidi_drop_output(substream);
335 }
336 }
337
f_midi_start_ep(struct f_midi * midi,struct usb_function * f,struct usb_ep * ep)338 static int f_midi_start_ep(struct f_midi *midi,
339 struct usb_function *f,
340 struct usb_ep *ep)
341 {
342 int err;
343 struct usb_composite_dev *cdev = f->config->cdev;
344
345 usb_ep_disable(ep);
346
347 err = config_ep_by_speed(midi->gadget, f, ep);
348 if (err) {
349 ERROR(cdev, "can't configure %s: %d\n", ep->name, err);
350 return err;
351 }
352
353 err = usb_ep_enable(ep);
354 if (err) {
355 ERROR(cdev, "can't start %s: %d\n", ep->name, err);
356 return err;
357 }
358
359 ep->driver_data = midi;
360
361 return 0;
362 }
363
f_midi_set_alt(struct usb_function * f,unsigned intf,unsigned alt)364 static int f_midi_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
365 {
366 struct f_midi *midi = func_to_midi(f);
367 unsigned i;
368 int err;
369
370 /* we only set alt for MIDIStreaming interface */
371 if (intf != midi->ms_id)
372 return 0;
373
374 err = f_midi_start_ep(midi, f, midi->in_ep);
375 if (err)
376 return err;
377
378 err = f_midi_start_ep(midi, f, midi->out_ep);
379 if (err)
380 return err;
381
382 /* pre-allocate write usb requests to use on f_midi_transmit. */
383 while (kfifo_avail(&midi->in_req_fifo)) {
384 struct usb_request *req =
385 midi_alloc_ep_req(midi->in_ep, midi->buflen);
386
387 if (req == NULL)
388 return -ENOMEM;
389
390 req->length = 0;
391 req->complete = f_midi_complete;
392
393 kfifo_put(&midi->in_req_fifo, req);
394 }
395
396 /* allocate a bunch of read buffers and queue them all at once. */
397 for (i = 0; i < midi->qlen && err == 0; i++) {
398 struct usb_request *req =
399 midi_alloc_ep_req(midi->out_ep, midi->buflen);
400
401 if (req == NULL)
402 return -ENOMEM;
403
404 req->complete = f_midi_complete;
405 err = usb_ep_queue(midi->out_ep, req, GFP_ATOMIC);
406 if (err) {
407 ERROR(midi, "%s: couldn't enqueue request: %d\n",
408 midi->out_ep->name, err);
409 if (req->buf != NULL)
410 free_ep_req(midi->out_ep, req);
411 return err;
412 }
413 }
414
415 return 0;
416 }
417
f_midi_disable(struct usb_function * f)418 static void f_midi_disable(struct usb_function *f)
419 {
420 struct f_midi *midi = func_to_midi(f);
421 struct usb_composite_dev *cdev = f->config->cdev;
422 struct usb_request *req = NULL;
423
424 DBG(cdev, "disable\n");
425
426 /*
427 * just disable endpoints, forcing completion of pending i/o.
428 * all our completion handlers free their requests in this case.
429 */
430 usb_ep_disable(midi->in_ep);
431 usb_ep_disable(midi->out_ep);
432
433 /* release IN requests */
434 while (kfifo_get(&midi->in_req_fifo, &req))
435 free_ep_req(midi->in_ep, req);
436
437 f_midi_drop_out_substreams(midi);
438 }
439
f_midi_snd_free(struct snd_device * device)440 static int f_midi_snd_free(struct snd_device *device)
441 {
442 return 0;
443 }
444
445 /*
446 * Converts MIDI commands to USB MIDI packets.
447 */
f_midi_transmit_byte(struct usb_request * req,struct gmidi_in_port * port,uint8_t b)448 static void f_midi_transmit_byte(struct usb_request *req,
449 struct gmidi_in_port *port, uint8_t b)
450 {
451 uint8_t p[4] = { port->cable << 4, 0, 0, 0 };
452 uint8_t next_state = STATE_INITIAL;
453
454 switch (b) {
455 case 0xf8 ... 0xff:
456 /* System Real-Time Messages */
457 p[0] |= 0x0f;
458 p[1] = b;
459 next_state = port->state;
460 port->state = STATE_REAL_TIME;
461 break;
462
463 case 0xf7:
464 /* End of SysEx */
465 switch (port->state) {
466 case STATE_SYSEX_0:
467 p[0] |= 0x05;
468 p[1] = 0xf7;
469 next_state = STATE_FINISHED;
470 break;
471 case STATE_SYSEX_1:
472 p[0] |= 0x06;
473 p[1] = port->data[0];
474 p[2] = 0xf7;
475 next_state = STATE_FINISHED;
476 break;
477 case STATE_SYSEX_2:
478 p[0] |= 0x07;
479 p[1] = port->data[0];
480 p[2] = port->data[1];
481 p[3] = 0xf7;
482 next_state = STATE_FINISHED;
483 break;
484 default:
485 /* Ignore byte */
486 next_state = port->state;
487 port->state = STATE_INITIAL;
488 }
489 break;
490
491 case 0xf0 ... 0xf6:
492 /* System Common Messages */
493 port->data[0] = port->data[1] = 0;
494 port->state = STATE_INITIAL;
495 switch (b) {
496 case 0xf0:
497 port->data[0] = b;
498 port->data[1] = 0;
499 next_state = STATE_SYSEX_1;
500 break;
501 case 0xf1:
502 case 0xf3:
503 port->data[0] = b;
504 next_state = STATE_1PARAM;
505 break;
506 case 0xf2:
507 port->data[0] = b;
508 next_state = STATE_2PARAM_1;
509 break;
510 case 0xf4:
511 case 0xf5:
512 next_state = STATE_INITIAL;
513 break;
514 case 0xf6:
515 p[0] |= 0x05;
516 p[1] = 0xf6;
517 next_state = STATE_FINISHED;
518 break;
519 }
520 break;
521
522 case 0x80 ... 0xef:
523 /*
524 * Channel Voice Messages, Channel Mode Messages
525 * and Control Change Messages.
526 */
527 port->data[0] = b;
528 port->data[1] = 0;
529 port->state = STATE_INITIAL;
530 if (b >= 0xc0 && b <= 0xdf)
531 next_state = STATE_1PARAM;
532 else
533 next_state = STATE_2PARAM_1;
534 break;
535
536 case 0x00 ... 0x7f:
537 /* Message parameters */
538 switch (port->state) {
539 case STATE_1PARAM:
540 if (port->data[0] < 0xf0)
541 p[0] |= port->data[0] >> 4;
542 else
543 p[0] |= 0x02;
544
545 p[1] = port->data[0];
546 p[2] = b;
547 /* This is to allow Running State Messages */
548 next_state = STATE_1PARAM;
549 break;
550 case STATE_2PARAM_1:
551 port->data[1] = b;
552 next_state = STATE_2PARAM_2;
553 break;
554 case STATE_2PARAM_2:
555 if (port->data[0] < 0xf0)
556 p[0] |= port->data[0] >> 4;
557 else
558 p[0] |= 0x03;
559
560 p[1] = port->data[0];
561 p[2] = port->data[1];
562 p[3] = b;
563 /* This is to allow Running State Messages */
564 next_state = STATE_2PARAM_1;
565 break;
566 case STATE_SYSEX_0:
567 port->data[0] = b;
568 next_state = STATE_SYSEX_1;
569 break;
570 case STATE_SYSEX_1:
571 port->data[1] = b;
572 next_state = STATE_SYSEX_2;
573 break;
574 case STATE_SYSEX_2:
575 p[0] |= 0x04;
576 p[1] = port->data[0];
577 p[2] = port->data[1];
578 p[3] = b;
579 next_state = STATE_SYSEX_0;
580 break;
581 }
582 break;
583 }
584
585 /* States where we have to write into the USB request */
586 if (next_state == STATE_FINISHED ||
587 port->state == STATE_SYSEX_2 ||
588 port->state == STATE_1PARAM ||
589 port->state == STATE_2PARAM_2 ||
590 port->state == STATE_REAL_TIME) {
591
592 unsigned int length = req->length;
593 u8 *buf = (u8 *)req->buf + length;
594
595 memcpy(buf, p, sizeof(p));
596 req->length = length + sizeof(p);
597
598 if (next_state == STATE_FINISHED) {
599 next_state = STATE_INITIAL;
600 port->data[0] = port->data[1] = 0;
601 }
602 }
603
604 port->state = next_state;
605 }
606
f_midi_do_transmit(struct f_midi * midi,struct usb_ep * ep)607 static int f_midi_do_transmit(struct f_midi *midi, struct usb_ep *ep)
608 {
609 struct usb_request *req = NULL;
610 unsigned int len, i;
611 bool active = false;
612 int err;
613
614 /*
615 * We peek the request in order to reuse it if it fails to enqueue on
616 * its endpoint
617 */
618 len = kfifo_peek(&midi->in_req_fifo, &req);
619 if (len != 1) {
620 ERROR(midi, "%s: Couldn't get usb request\n", __func__);
621 return -1;
622 }
623
624 /*
625 * If buffer overrun, then we ignore this transmission.
626 * IMPORTANT: This will cause the user-space rawmidi device to block
627 * until a) usb requests have been completed or b) snd_rawmidi_write()
628 * times out.
629 */
630 if (req->length > 0)
631 return 0;
632
633 for (i = midi->in_last_port; i < midi->in_ports; ++i) {
634 struct gmidi_in_port *port = midi->in_ports_array + i;
635 struct snd_rawmidi_substream *substream = port->substream;
636
637 if (!port->active || !substream)
638 continue;
639
640 while (req->length + 3 < midi->buflen) {
641 uint8_t b;
642
643 if (snd_rawmidi_transmit(substream, &b, 1) != 1) {
644 port->active = 0;
645 break;
646 }
647 f_midi_transmit_byte(req, port, b);
648 }
649
650 active = !!port->active;
651 if (active)
652 break;
653 }
654 midi->in_last_port = active ? i : 0;
655
656 if (req->length <= 0)
657 goto done;
658
659 err = usb_ep_queue(ep, req, GFP_ATOMIC);
660 if (err < 0) {
661 ERROR(midi, "%s failed to queue req: %d\n",
662 midi->in_ep->name, err);
663 req->length = 0; /* Re-use request next time. */
664 } else {
665 /* Upon success, put request at the back of the queue. */
666 kfifo_skip(&midi->in_req_fifo);
667 kfifo_put(&midi->in_req_fifo, req);
668 }
669
670 done:
671 return active;
672 }
673
f_midi_transmit(struct f_midi * midi)674 static void f_midi_transmit(struct f_midi *midi)
675 {
676 struct usb_ep *ep = midi->in_ep;
677 int ret;
678 unsigned long flags;
679
680 /* We only care about USB requests if IN endpoint is enabled */
681 if (!ep || !ep->enabled)
682 goto drop_out;
683
684 spin_lock_irqsave(&midi->transmit_lock, flags);
685
686 do {
687 ret = f_midi_do_transmit(midi, ep);
688 if (ret < 0) {
689 spin_unlock_irqrestore(&midi->transmit_lock, flags);
690 goto drop_out;
691 }
692 } while (ret);
693
694 spin_unlock_irqrestore(&midi->transmit_lock, flags);
695
696 return;
697
698 drop_out:
699 f_midi_drop_out_substreams(midi);
700 }
701
f_midi_in_work(struct work_struct * work)702 static void f_midi_in_work(struct work_struct *work)
703 {
704 struct f_midi *midi;
705
706 midi = container_of(work, struct f_midi, work);
707 f_midi_transmit(midi);
708 }
709
f_midi_in_open(struct snd_rawmidi_substream * substream)710 static int f_midi_in_open(struct snd_rawmidi_substream *substream)
711 {
712 struct f_midi *midi = substream->rmidi->private_data;
713 struct gmidi_in_port *port;
714
715 if (substream->number >= midi->in_ports)
716 return -EINVAL;
717
718 VDBG(midi, "%s()\n", __func__);
719 port = midi->in_ports_array + substream->number;
720 port->substream = substream;
721 port->state = STATE_INITIAL;
722 return 0;
723 }
724
f_midi_in_close(struct snd_rawmidi_substream * substream)725 static int f_midi_in_close(struct snd_rawmidi_substream *substream)
726 {
727 struct f_midi *midi = substream->rmidi->private_data;
728
729 VDBG(midi, "%s()\n", __func__);
730 return 0;
731 }
732
f_midi_in_trigger(struct snd_rawmidi_substream * substream,int up)733 static void f_midi_in_trigger(struct snd_rawmidi_substream *substream, int up)
734 {
735 struct f_midi *midi = substream->rmidi->private_data;
736
737 if (substream->number >= midi->in_ports)
738 return;
739
740 VDBG(midi, "%s() %d\n", __func__, up);
741 midi->in_ports_array[substream->number].active = up;
742 if (up)
743 queue_work(system_highpri_wq, &midi->work);
744 }
745
f_midi_out_open(struct snd_rawmidi_substream * substream)746 static int f_midi_out_open(struct snd_rawmidi_substream *substream)
747 {
748 struct f_midi *midi = substream->rmidi->private_data;
749
750 if (substream->number >= MAX_PORTS)
751 return -EINVAL;
752
753 VDBG(midi, "%s()\n", __func__);
754 midi->out_substream[substream->number] = substream;
755 return 0;
756 }
757
f_midi_out_close(struct snd_rawmidi_substream * substream)758 static int f_midi_out_close(struct snd_rawmidi_substream *substream)
759 {
760 struct f_midi *midi = substream->rmidi->private_data;
761
762 VDBG(midi, "%s()\n", __func__);
763 return 0;
764 }
765
f_midi_out_trigger(struct snd_rawmidi_substream * substream,int up)766 static void f_midi_out_trigger(struct snd_rawmidi_substream *substream, int up)
767 {
768 struct f_midi *midi = substream->rmidi->private_data;
769
770 VDBG(midi, "%s()\n", __func__);
771
772 if (up)
773 set_bit(substream->number, &midi->out_triggered);
774 else
775 clear_bit(substream->number, &midi->out_triggered);
776 }
777
778 static const struct snd_rawmidi_ops gmidi_in_ops = {
779 .open = f_midi_in_open,
780 .close = f_midi_in_close,
781 .trigger = f_midi_in_trigger,
782 };
783
784 static const struct snd_rawmidi_ops gmidi_out_ops = {
785 .open = f_midi_out_open,
786 .close = f_midi_out_close,
787 .trigger = f_midi_out_trigger
788 };
789
f_midi_unregister_card(struct f_midi * midi)790 static inline void f_midi_unregister_card(struct f_midi *midi)
791 {
792 if (midi->card) {
793 snd_card_free(midi->card);
794 midi->card = NULL;
795 }
796 }
797
798 /* register as a sound "card" */
f_midi_register_card(struct f_midi * midi)799 static int f_midi_register_card(struct f_midi *midi)
800 {
801 struct snd_card *card;
802 struct snd_rawmidi *rmidi;
803 int err;
804 static struct snd_device_ops ops = {
805 .dev_free = f_midi_snd_free,
806 };
807
808 err = snd_card_new(&midi->gadget->dev, midi->index, midi->id,
809 THIS_MODULE, 0, &card);
810 if (err < 0) {
811 ERROR(midi, "snd_card_new() failed\n");
812 goto fail;
813 }
814 midi->card = card;
815
816 err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, midi, &ops);
817 if (err < 0) {
818 ERROR(midi, "snd_device_new() failed: error %d\n", err);
819 goto fail;
820 }
821
822 strcpy(card->driver, f_midi_longname);
823 strcpy(card->longname, f_midi_longname);
824 strcpy(card->shortname, f_midi_shortname);
825
826 /* Set up rawmidi */
827 snd_component_add(card, "MIDI");
828 err = snd_rawmidi_new(card, card->longname, 0,
829 midi->out_ports, midi->in_ports, &rmidi);
830 if (err < 0) {
831 ERROR(midi, "snd_rawmidi_new() failed: error %d\n", err);
832 goto fail;
833 }
834 midi->rmidi = rmidi;
835 midi->in_last_port = 0;
836 strcpy(rmidi->name, card->shortname);
837 rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
838 SNDRV_RAWMIDI_INFO_INPUT |
839 SNDRV_RAWMIDI_INFO_DUPLEX;
840 rmidi->private_data = midi;
841 rmidi->private_free = f_midi_rmidi_free;
842 midi->free_ref++;
843
844 /*
845 * Yes, rawmidi OUTPUT = USB IN, and rawmidi INPUT = USB OUT.
846 * It's an upside-down world being a gadget.
847 */
848 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &gmidi_in_ops);
849 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &gmidi_out_ops);
850
851 /* register it - we're ready to go */
852 err = snd_card_register(card);
853 if (err < 0) {
854 ERROR(midi, "snd_card_register() failed\n");
855 goto fail;
856 }
857
858 VDBG(midi, "%s() finished ok\n", __func__);
859 return 0;
860
861 fail:
862 f_midi_unregister_card(midi);
863 return err;
864 }
865
866 /* MIDI function driver setup/binding */
867
f_midi_bind(struct usb_configuration * c,struct usb_function * f)868 static int f_midi_bind(struct usb_configuration *c, struct usb_function *f)
869 {
870 struct usb_descriptor_header **midi_function;
871 struct usb_midi_in_jack_descriptor jack_in_ext_desc[MAX_PORTS];
872 struct usb_midi_in_jack_descriptor jack_in_emb_desc[MAX_PORTS];
873 struct usb_midi_out_jack_descriptor_1 jack_out_ext_desc[MAX_PORTS];
874 struct usb_midi_out_jack_descriptor_1 jack_out_emb_desc[MAX_PORTS];
875 struct usb_composite_dev *cdev = c->cdev;
876 struct f_midi *midi = func_to_midi(f);
877 struct usb_string *us;
878 int status, n, jack = 1, i = 0, endpoint_descriptor_index = 0;
879
880 midi->gadget = cdev->gadget;
881 INIT_WORK(&midi->work, f_midi_in_work);
882 status = f_midi_register_card(midi);
883 if (status < 0)
884 goto fail_register;
885
886 /* maybe allocate device-global string ID */
887 us = usb_gstrings_attach(c->cdev, midi_strings,
888 ARRAY_SIZE(midi_string_defs));
889 if (IS_ERR(us)) {
890 status = PTR_ERR(us);
891 goto fail;
892 }
893 ac_interface_desc.iInterface = us[STRING_FUNC_IDX].id;
894
895 /* We have two interfaces, AudioControl and MIDIStreaming */
896 status = usb_interface_id(c, f);
897 if (status < 0)
898 goto fail;
899 ac_interface_desc.bInterfaceNumber = status;
900
901 status = usb_interface_id(c, f);
902 if (status < 0)
903 goto fail;
904 ms_interface_desc.bInterfaceNumber = status;
905 ac_header_desc.baInterfaceNr[0] = status;
906 midi->ms_id = status;
907
908 status = -ENODEV;
909
910 /* allocate instance-specific endpoints */
911 midi->in_ep = usb_ep_autoconfig(cdev->gadget, &bulk_in_desc);
912 if (!midi->in_ep)
913 goto fail;
914
915 midi->out_ep = usb_ep_autoconfig(cdev->gadget, &bulk_out_desc);
916 if (!midi->out_ep)
917 goto fail;
918
919 /* allocate temporary function list */
920 midi_function = kcalloc((MAX_PORTS * 4) + 11, sizeof(*midi_function),
921 GFP_KERNEL);
922 if (!midi_function) {
923 status = -ENOMEM;
924 goto fail;
925 }
926
927 /*
928 * construct the function's descriptor set. As the number of
929 * input and output MIDI ports is configurable, we have to do
930 * it that way.
931 */
932
933 /* add the headers - these are always the same */
934 midi_function[i++] = (struct usb_descriptor_header *) &ac_interface_desc;
935 midi_function[i++] = (struct usb_descriptor_header *) &ac_header_desc;
936 midi_function[i++] = (struct usb_descriptor_header *) &ms_interface_desc;
937
938 /* calculate the header's wTotalLength */
939 n = USB_DT_MS_HEADER_SIZE
940 + (midi->in_ports + midi->out_ports) *
941 (USB_DT_MIDI_IN_SIZE + USB_DT_MIDI_OUT_SIZE(1));
942 ms_header_desc.wTotalLength = cpu_to_le16(n);
943
944 midi_function[i++] = (struct usb_descriptor_header *) &ms_header_desc;
945
946 /* configure the external IN jacks, each linked to an embedded OUT jack */
947 for (n = 0; n < midi->in_ports; n++) {
948 struct usb_midi_in_jack_descriptor *in_ext = &jack_in_ext_desc[n];
949 struct usb_midi_out_jack_descriptor_1 *out_emb = &jack_out_emb_desc[n];
950
951 in_ext->bLength = USB_DT_MIDI_IN_SIZE;
952 in_ext->bDescriptorType = USB_DT_CS_INTERFACE;
953 in_ext->bDescriptorSubtype = USB_MS_MIDI_IN_JACK;
954 in_ext->bJackType = USB_MS_EXTERNAL;
955 in_ext->bJackID = jack++;
956 in_ext->iJack = 0;
957 midi_function[i++] = (struct usb_descriptor_header *) in_ext;
958
959 out_emb->bLength = USB_DT_MIDI_OUT_SIZE(1);
960 out_emb->bDescriptorType = USB_DT_CS_INTERFACE;
961 out_emb->bDescriptorSubtype = USB_MS_MIDI_OUT_JACK;
962 out_emb->bJackType = USB_MS_EMBEDDED;
963 out_emb->bJackID = jack++;
964 out_emb->bNrInputPins = 1;
965 out_emb->pins[0].baSourcePin = 1;
966 out_emb->pins[0].baSourceID = in_ext->bJackID;
967 out_emb->iJack = 0;
968 midi_function[i++] = (struct usb_descriptor_header *) out_emb;
969
970 /* link it to the endpoint */
971 ms_in_desc.baAssocJackID[n] = out_emb->bJackID;
972 }
973
974 /* configure the external OUT jacks, each linked to an embedded IN jack */
975 for (n = 0; n < midi->out_ports; n++) {
976 struct usb_midi_in_jack_descriptor *in_emb = &jack_in_emb_desc[n];
977 struct usb_midi_out_jack_descriptor_1 *out_ext = &jack_out_ext_desc[n];
978
979 in_emb->bLength = USB_DT_MIDI_IN_SIZE;
980 in_emb->bDescriptorType = USB_DT_CS_INTERFACE;
981 in_emb->bDescriptorSubtype = USB_MS_MIDI_IN_JACK;
982 in_emb->bJackType = USB_MS_EMBEDDED;
983 in_emb->bJackID = jack++;
984 in_emb->iJack = 0;
985 midi_function[i++] = (struct usb_descriptor_header *) in_emb;
986
987 out_ext->bLength = USB_DT_MIDI_OUT_SIZE(1);
988 out_ext->bDescriptorType = USB_DT_CS_INTERFACE;
989 out_ext->bDescriptorSubtype = USB_MS_MIDI_OUT_JACK;
990 out_ext->bJackType = USB_MS_EXTERNAL;
991 out_ext->bJackID = jack++;
992 out_ext->bNrInputPins = 1;
993 out_ext->iJack = 0;
994 out_ext->pins[0].baSourceID = in_emb->bJackID;
995 out_ext->pins[0].baSourcePin = 1;
996 midi_function[i++] = (struct usb_descriptor_header *) out_ext;
997
998 /* link it to the endpoint */
999 ms_out_desc.baAssocJackID[n] = in_emb->bJackID;
1000 }
1001
1002 /* configure the endpoint descriptors ... */
1003 ms_out_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->in_ports);
1004 ms_out_desc.bNumEmbMIDIJack = midi->in_ports;
1005
1006 ms_in_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->out_ports);
1007 ms_in_desc.bNumEmbMIDIJack = midi->out_ports;
1008
1009 /* ... and add them to the list */
1010 endpoint_descriptor_index = i;
1011 midi_function[i++] = (struct usb_descriptor_header *) &bulk_out_desc;
1012 midi_function[i++] = (struct usb_descriptor_header *) &ms_out_desc;
1013 midi_function[i++] = (struct usb_descriptor_header *) &bulk_in_desc;
1014 midi_function[i++] = (struct usb_descriptor_header *) &ms_in_desc;
1015 midi_function[i++] = NULL;
1016
1017 /*
1018 * support all relevant hardware speeds... we expect that when
1019 * hardware is dual speed, all bulk-capable endpoints work at
1020 * both speeds
1021 */
1022 /* copy descriptors, and track endpoint copies */
1023 f->fs_descriptors = usb_copy_descriptors(midi_function);
1024 if (!f->fs_descriptors)
1025 goto fail_f_midi;
1026
1027 bulk_in_desc.wMaxPacketSize = cpu_to_le16(512);
1028 bulk_out_desc.wMaxPacketSize = cpu_to_le16(512);
1029 f->hs_descriptors = usb_copy_descriptors(midi_function);
1030 if (!f->hs_descriptors)
1031 goto fail_f_midi;
1032
1033 bulk_in_desc.wMaxPacketSize = cpu_to_le16(1024);
1034 bulk_out_desc.wMaxPacketSize = cpu_to_le16(1024);
1035 i = endpoint_descriptor_index;
1036 midi_function[i++] = (struct usb_descriptor_header *)
1037 &bulk_out_desc;
1038 midi_function[i++] = (struct usb_descriptor_header *)
1039 &bulk_out_ss_comp_desc;
1040 midi_function[i++] = (struct usb_descriptor_header *)
1041 &ms_out_desc;
1042 midi_function[i++] = (struct usb_descriptor_header *)
1043 &bulk_in_desc;
1044 midi_function[i++] = (struct usb_descriptor_header *)
1045 &bulk_in_ss_comp_desc;
1046 midi_function[i++] = (struct usb_descriptor_header *)
1047 &ms_in_desc;
1048 f->ss_descriptors = usb_copy_descriptors(midi_function);
1049 if (!f->ss_descriptors)
1050 goto fail_f_midi;
1051
1052 kfree(midi_function);
1053
1054 return 0;
1055
1056 fail_f_midi:
1057 kfree(midi_function);
1058 usb_free_all_descriptors(f);
1059 fail:
1060 f_midi_unregister_card(midi);
1061 fail_register:
1062 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1063
1064 return status;
1065 }
1066
to_f_midi_opts(struct config_item * item)1067 static inline struct f_midi_opts *to_f_midi_opts(struct config_item *item)
1068 {
1069 return container_of(to_config_group(item), struct f_midi_opts,
1070 func_inst.group);
1071 }
1072
midi_attr_release(struct config_item * item)1073 static void midi_attr_release(struct config_item *item)
1074 {
1075 struct f_midi_opts *opts = to_f_midi_opts(item);
1076
1077 usb_put_function_instance(&opts->func_inst);
1078 }
1079
1080 static struct configfs_item_operations midi_item_ops = {
1081 .release = midi_attr_release,
1082 };
1083
1084 #define F_MIDI_OPT(name, test_limit, limit) \
1085 static ssize_t f_midi_opts_##name##_show(struct config_item *item, char *page) \
1086 { \
1087 struct f_midi_opts *opts = to_f_midi_opts(item); \
1088 int result; \
1089 \
1090 mutex_lock(&opts->lock); \
1091 result = sprintf(page, "%u\n", opts->name); \
1092 mutex_unlock(&opts->lock); \
1093 \
1094 return result; \
1095 } \
1096 \
1097 static ssize_t f_midi_opts_##name##_store(struct config_item *item, \
1098 const char *page, size_t len) \
1099 { \
1100 struct f_midi_opts *opts = to_f_midi_opts(item); \
1101 int ret; \
1102 u32 num; \
1103 \
1104 mutex_lock(&opts->lock); \
1105 if (opts->refcnt > 1) { \
1106 ret = -EBUSY; \
1107 goto end; \
1108 } \
1109 \
1110 ret = kstrtou32(page, 0, &num); \
1111 if (ret) \
1112 goto end; \
1113 \
1114 if (test_limit && num > limit) { \
1115 ret = -EINVAL; \
1116 goto end; \
1117 } \
1118 opts->name = num; \
1119 ret = len; \
1120 \
1121 end: \
1122 mutex_unlock(&opts->lock); \
1123 return ret; \
1124 } \
1125 \
1126 CONFIGFS_ATTR(f_midi_opts_, name);
1127
1128 #define F_MIDI_OPT_SIGNED(name, test_limit, limit) \
1129 static ssize_t f_midi_opts_##name##_show(struct config_item *item, char *page) \
1130 { \
1131 struct f_midi_opts *opts = to_f_midi_opts(item); \
1132 int result; \
1133 \
1134 mutex_lock(&opts->lock); \
1135 result = sprintf(page, "%d\n", opts->name); \
1136 mutex_unlock(&opts->lock); \
1137 \
1138 return result; \
1139 } \
1140 \
1141 static ssize_t f_midi_opts_##name##_store(struct config_item *item, \
1142 const char *page, size_t len) \
1143 { \
1144 struct f_midi_opts *opts = to_f_midi_opts(item); \
1145 int ret; \
1146 s32 num; \
1147 \
1148 mutex_lock(&opts->lock); \
1149 if (opts->refcnt > 1) { \
1150 ret = -EBUSY; \
1151 goto end; \
1152 } \
1153 \
1154 ret = kstrtos32(page, 0, &num); \
1155 if (ret) \
1156 goto end; \
1157 \
1158 if (test_limit && num > limit) { \
1159 ret = -EINVAL; \
1160 goto end; \
1161 } \
1162 opts->name = num; \
1163 ret = len; \
1164 \
1165 end: \
1166 mutex_unlock(&opts->lock); \
1167 return ret; \
1168 } \
1169 \
1170 CONFIGFS_ATTR(f_midi_opts_, name);
1171
1172 F_MIDI_OPT_SIGNED(index, true, SNDRV_CARDS);
1173 F_MIDI_OPT(buflen, false, 0);
1174 F_MIDI_OPT(qlen, false, 0);
1175 F_MIDI_OPT(in_ports, true, MAX_PORTS);
1176 F_MIDI_OPT(out_ports, true, MAX_PORTS);
1177
f_midi_opts_id_show(struct config_item * item,char * page)1178 static ssize_t f_midi_opts_id_show(struct config_item *item, char *page)
1179 {
1180 struct f_midi_opts *opts = to_f_midi_opts(item);
1181 ssize_t result;
1182
1183 mutex_lock(&opts->lock);
1184 if (opts->id) {
1185 result = strscpy(page, opts->id, PAGE_SIZE);
1186 } else {
1187 page[0] = 0;
1188 result = 0;
1189 }
1190
1191 mutex_unlock(&opts->lock);
1192
1193 return result;
1194 }
1195
f_midi_opts_id_store(struct config_item * item,const char * page,size_t len)1196 static ssize_t f_midi_opts_id_store(struct config_item *item,
1197 const char *page, size_t len)
1198 {
1199 struct f_midi_opts *opts = to_f_midi_opts(item);
1200 int ret;
1201 char *c;
1202
1203 mutex_lock(&opts->lock);
1204 if (opts->refcnt > 1) {
1205 ret = -EBUSY;
1206 goto end;
1207 }
1208
1209 c = kstrndup(page, len, GFP_KERNEL);
1210 if (!c) {
1211 ret = -ENOMEM;
1212 goto end;
1213 }
1214 if (opts->id_allocated)
1215 kfree(opts->id);
1216 opts->id = c;
1217 opts->id_allocated = true;
1218 ret = len;
1219 end:
1220 mutex_unlock(&opts->lock);
1221 return ret;
1222 }
1223
1224 CONFIGFS_ATTR(f_midi_opts_, id);
1225
1226 static struct configfs_attribute *midi_attrs[] = {
1227 &f_midi_opts_attr_index,
1228 &f_midi_opts_attr_buflen,
1229 &f_midi_opts_attr_qlen,
1230 &f_midi_opts_attr_in_ports,
1231 &f_midi_opts_attr_out_ports,
1232 &f_midi_opts_attr_id,
1233 NULL,
1234 };
1235
1236 static const struct config_item_type midi_func_type = {
1237 .ct_item_ops = &midi_item_ops,
1238 .ct_attrs = midi_attrs,
1239 .ct_owner = THIS_MODULE,
1240 };
1241
f_midi_free_inst(struct usb_function_instance * f)1242 static void f_midi_free_inst(struct usb_function_instance *f)
1243 {
1244 struct f_midi_opts *opts;
1245 bool free = false;
1246
1247 opts = container_of(f, struct f_midi_opts, func_inst);
1248
1249 mutex_lock(&opts->lock);
1250 if (!--opts->refcnt) {
1251 free = true;
1252 }
1253 mutex_unlock(&opts->lock);
1254
1255 if (free) {
1256 if (opts->id_allocated)
1257 kfree(opts->id);
1258 kfree(opts);
1259 }
1260 }
1261
f_midi_alloc_inst(void)1262 static struct usb_function_instance *f_midi_alloc_inst(void)
1263 {
1264 struct f_midi_opts *opts;
1265
1266 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1267 if (!opts)
1268 return ERR_PTR(-ENOMEM);
1269
1270 mutex_init(&opts->lock);
1271 opts->func_inst.free_func_inst = f_midi_free_inst;
1272 opts->index = SNDRV_DEFAULT_IDX1;
1273 opts->id = SNDRV_DEFAULT_STR1;
1274 opts->buflen = 512;
1275 opts->qlen = 32;
1276 opts->in_ports = 1;
1277 opts->out_ports = 1;
1278 opts->refcnt = 1;
1279
1280 config_group_init_type_name(&opts->func_inst.group, "",
1281 &midi_func_type);
1282
1283 return &opts->func_inst;
1284 }
1285
f_midi_free(struct usb_function * f)1286 static void f_midi_free(struct usb_function *f)
1287 {
1288 struct f_midi *midi;
1289 struct f_midi_opts *opts;
1290 bool free = false;
1291
1292 midi = func_to_midi(f);
1293 opts = container_of(f->fi, struct f_midi_opts, func_inst);
1294 mutex_lock(&opts->lock);
1295 if (!--midi->free_ref) {
1296 kfree(midi->id);
1297 kfifo_free(&midi->in_req_fifo);
1298 kfree(midi);
1299 free = true;
1300 }
1301 mutex_unlock(&opts->lock);
1302
1303 if (free)
1304 f_midi_free_inst(&opts->func_inst);
1305 }
1306
f_midi_rmidi_free(struct snd_rawmidi * rmidi)1307 static void f_midi_rmidi_free(struct snd_rawmidi *rmidi)
1308 {
1309 f_midi_free(rmidi->private_data);
1310 }
1311
f_midi_unbind(struct usb_configuration * c,struct usb_function * f)1312 static void f_midi_unbind(struct usb_configuration *c, struct usb_function *f)
1313 {
1314 struct usb_composite_dev *cdev = f->config->cdev;
1315 struct f_midi *midi = func_to_midi(f);
1316 struct snd_card *card;
1317
1318 DBG(cdev, "unbind\n");
1319
1320 /* just to be sure */
1321 f_midi_disable(f);
1322
1323 card = midi->card;
1324 midi->card = NULL;
1325 if (card)
1326 snd_card_free_when_closed(card);
1327
1328 usb_free_all_descriptors(f);
1329 }
1330
f_midi_alloc(struct usb_function_instance * fi)1331 static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)
1332 {
1333 struct f_midi *midi = NULL;
1334 struct f_midi_opts *opts;
1335 int status, i;
1336
1337 opts = container_of(fi, struct f_midi_opts, func_inst);
1338
1339 mutex_lock(&opts->lock);
1340 /* sanity check */
1341 if (opts->in_ports > MAX_PORTS || opts->out_ports > MAX_PORTS) {
1342 status = -EINVAL;
1343 goto setup_fail;
1344 }
1345
1346 /* allocate and initialize one new instance */
1347 midi = kzalloc(struct_size(midi, in_ports_array, opts->in_ports),
1348 GFP_KERNEL);
1349 if (!midi) {
1350 status = -ENOMEM;
1351 goto setup_fail;
1352 }
1353 midi->in_ports = opts->in_ports;
1354
1355 for (i = 0; i < opts->in_ports; i++)
1356 midi->in_ports_array[i].cable = i;
1357
1358 /* set up ALSA midi devices */
1359 midi->id = kstrdup(opts->id, GFP_KERNEL);
1360 if (opts->id && !midi->id) {
1361 status = -ENOMEM;
1362 goto midi_free;
1363 }
1364 midi->out_ports = opts->out_ports;
1365 midi->index = opts->index;
1366 midi->buflen = opts->buflen;
1367 midi->qlen = opts->qlen;
1368 midi->in_last_port = 0;
1369 midi->free_ref = 1;
1370
1371 status = kfifo_alloc(&midi->in_req_fifo, midi->qlen, GFP_KERNEL);
1372 if (status)
1373 goto midi_free;
1374
1375 spin_lock_init(&midi->transmit_lock);
1376
1377 ++opts->refcnt;
1378 mutex_unlock(&opts->lock);
1379
1380 midi->func.name = "gmidi function";
1381 midi->func.bind = f_midi_bind;
1382 midi->func.unbind = f_midi_unbind;
1383 midi->func.set_alt = f_midi_set_alt;
1384 midi->func.disable = f_midi_disable;
1385 midi->func.free_func = f_midi_free;
1386
1387 return &midi->func;
1388
1389 midi_free:
1390 if (midi)
1391 kfree(midi->id);
1392 kfree(midi);
1393 setup_fail:
1394 mutex_unlock(&opts->lock);
1395
1396 return ERR_PTR(status);
1397 }
1398
1399 DECLARE_USB_FUNCTION_INIT(midi, f_midi_alloc_inst, f_midi_alloc);
1400