Merge remote-tracking branch 'mvebu/for-next'
[deliverable/linux.git] / drivers / usb / gadget / function / f_midi.c
1 /*
2 * f_midi.c -- USB MIDI class function driver
3 *
4 * Copyright (C) 2006 Thumtronics Pty Ltd.
5 * Developed for Thumtronics by Grey Innovation
6 * Ben Williamson <ben.williamson@greyinnovation.com>
7 *
8 * Rewritten for the composite framework
9 * Copyright (C) 2011 Daniel Mack <zonque@gmail.com>
10 *
11 * Based on drivers/usb/gadget/f_audio.c,
12 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
13 * Copyright (C) 2008 Analog Devices, Inc
14 *
15 * and drivers/usb/gadget/midi.c,
16 * Copyright (C) 2006 Thumtronics Pty Ltd.
17 * Ben Williamson <ben.williamson@greyinnovation.com>
18 *
19 * Licensed under the GPL-2 or later.
20 */
21
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/slab.h>
25 #include <linux/device.h>
26 #include <linux/kfifo.h>
27 #include <linux/spinlock.h>
28
29 #include <sound/core.h>
30 #include <sound/initval.h>
31 #include <sound/rawmidi.h>
32
33 #include <linux/usb/ch9.h>
34 #include <linux/usb/gadget.h>
35 #include <linux/usb/audio.h>
36 #include <linux/usb/midi.h>
37
38 #include "u_f.h"
39 #include "u_midi.h"
40
41 MODULE_AUTHOR("Ben Williamson");
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 /*
55 * This is a gadget, and the IN/OUT naming is from the host's perspective.
56 * USB -> OUT endpoint -> rawmidi
57 * USB <- IN endpoint <- rawmidi
58 */
59 struct gmidi_in_port {
60 struct snd_rawmidi_substream *substream;
61 int active;
62 uint8_t cable;
63 uint8_t state;
64 #define STATE_UNKNOWN 0
65 #define STATE_1PARAM 1
66 #define STATE_2PARAM_1 2
67 #define STATE_2PARAM_2 3
68 #define STATE_SYSEX_0 4
69 #define STATE_SYSEX_1 5
70 #define STATE_SYSEX_2 6
71 uint8_t data[2];
72 };
73
74 struct f_midi {
75 struct usb_function func;
76 struct usb_gadget *gadget;
77 struct usb_ep *in_ep, *out_ep;
78 struct snd_card *card;
79 struct snd_rawmidi *rmidi;
80 u8 ms_id;
81
82 struct snd_rawmidi_substream *out_substream[MAX_PORTS];
83
84 unsigned long out_triggered;
85 struct tasklet_struct tasklet;
86 unsigned int in_ports;
87 unsigned int out_ports;
88 int index;
89 char *id;
90 unsigned int buflen, qlen;
91 /* This fifo is used as a buffer ring for pre-allocated IN usb_requests */
92 DECLARE_KFIFO_PTR(in_req_fifo, struct usb_request *);
93 spinlock_t transmit_lock;
94 unsigned int in_last_port;
95
96 struct gmidi_in_port in_ports_array[/* in_ports */];
97 };
98
99 static inline struct f_midi *func_to_midi(struct usb_function *f)
100 {
101 return container_of(f, struct f_midi, func);
102 }
103
104 static void f_midi_transmit(struct f_midi *midi);
105
106 DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
107 DECLARE_USB_MIDI_OUT_JACK_DESCRIPTOR(1);
108 DECLARE_USB_MS_ENDPOINT_DESCRIPTOR(16);
109
110 /* B.3.1 Standard AC Interface Descriptor */
111 static struct usb_interface_descriptor ac_interface_desc = {
112 .bLength = USB_DT_INTERFACE_SIZE,
113 .bDescriptorType = USB_DT_INTERFACE,
114 /* .bInterfaceNumber = DYNAMIC */
115 /* .bNumEndpoints = DYNAMIC */
116 .bInterfaceClass = USB_CLASS_AUDIO,
117 .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
118 /* .iInterface = DYNAMIC */
119 };
120
121 /* B.3.2 Class-Specific AC Interface Descriptor */
122 static struct uac1_ac_header_descriptor_1 ac_header_desc = {
123 .bLength = UAC_DT_AC_HEADER_SIZE(1),
124 .bDescriptorType = USB_DT_CS_INTERFACE,
125 .bDescriptorSubtype = USB_MS_HEADER,
126 .bcdADC = cpu_to_le16(0x0100),
127 .wTotalLength = cpu_to_le16(UAC_DT_AC_HEADER_SIZE(1)),
128 .bInCollection = 1,
129 /* .baInterfaceNr = DYNAMIC */
130 };
131
132 /* B.4.1 Standard MS Interface Descriptor */
133 static struct usb_interface_descriptor ms_interface_desc = {
134 .bLength = USB_DT_INTERFACE_SIZE,
135 .bDescriptorType = USB_DT_INTERFACE,
136 /* .bInterfaceNumber = DYNAMIC */
137 .bNumEndpoints = 2,
138 .bInterfaceClass = USB_CLASS_AUDIO,
139 .bInterfaceSubClass = USB_SUBCLASS_MIDISTREAMING,
140 /* .iInterface = DYNAMIC */
141 };
142
143 /* B.4.2 Class-Specific MS Interface Descriptor */
144 static struct usb_ms_header_descriptor ms_header_desc = {
145 .bLength = USB_DT_MS_HEADER_SIZE,
146 .bDescriptorType = USB_DT_CS_INTERFACE,
147 .bDescriptorSubtype = USB_MS_HEADER,
148 .bcdMSC = cpu_to_le16(0x0100),
149 /* .wTotalLength = DYNAMIC */
150 };
151
152 /* B.5.1 Standard Bulk OUT Endpoint Descriptor */
153 static struct usb_endpoint_descriptor bulk_out_desc = {
154 .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
155 .bDescriptorType = USB_DT_ENDPOINT,
156 .bEndpointAddress = USB_DIR_OUT,
157 .bmAttributes = USB_ENDPOINT_XFER_BULK,
158 };
159
160 /* B.5.2 Class-specific MS Bulk OUT Endpoint Descriptor */
161 static struct usb_ms_endpoint_descriptor_16 ms_out_desc = {
162 /* .bLength = DYNAMIC */
163 .bDescriptorType = USB_DT_CS_ENDPOINT,
164 .bDescriptorSubtype = USB_MS_GENERAL,
165 /* .bNumEmbMIDIJack = DYNAMIC */
166 /* .baAssocJackID = DYNAMIC */
167 };
168
169 /* B.6.1 Standard Bulk IN Endpoint Descriptor */
170 static struct usb_endpoint_descriptor bulk_in_desc = {
171 .bLength = USB_DT_ENDPOINT_AUDIO_SIZE,
172 .bDescriptorType = USB_DT_ENDPOINT,
173 .bEndpointAddress = USB_DIR_IN,
174 .bmAttributes = USB_ENDPOINT_XFER_BULK,
175 };
176
177 /* B.6.2 Class-specific MS Bulk IN Endpoint Descriptor */
178 static struct usb_ms_endpoint_descriptor_16 ms_in_desc = {
179 /* .bLength = DYNAMIC */
180 .bDescriptorType = USB_DT_CS_ENDPOINT,
181 .bDescriptorSubtype = USB_MS_GENERAL,
182 /* .bNumEmbMIDIJack = DYNAMIC */
183 /* .baAssocJackID = DYNAMIC */
184 };
185
186 /* string IDs are assigned dynamically */
187
188 #define STRING_FUNC_IDX 0
189
190 static struct usb_string midi_string_defs[] = {
191 [STRING_FUNC_IDX].s = "MIDI function",
192 { } /* end of list */
193 };
194
195 static struct usb_gadget_strings midi_stringtab = {
196 .language = 0x0409, /* en-us */
197 .strings = midi_string_defs,
198 };
199
200 static struct usb_gadget_strings *midi_strings[] = {
201 &midi_stringtab,
202 NULL,
203 };
204
205 static inline struct usb_request *midi_alloc_ep_req(struct usb_ep *ep,
206 unsigned length)
207 {
208 return alloc_ep_req(ep, length, length);
209 }
210
211 static const uint8_t f_midi_cin_length[] = {
212 0, 0, 2, 3, 3, 1, 2, 3, 3, 3, 3, 3, 2, 2, 3, 1
213 };
214
215 /*
216 * Receives a chunk of MIDI data.
217 */
218 static void f_midi_read_data(struct usb_ep *ep, int cable,
219 uint8_t *data, int length)
220 {
221 struct f_midi *midi = ep->driver_data;
222 struct snd_rawmidi_substream *substream = midi->out_substream[cable];
223
224 if (!substream)
225 /* Nobody is listening - throw it on the floor. */
226 return;
227
228 if (!test_bit(cable, &midi->out_triggered))
229 return;
230
231 snd_rawmidi_receive(substream, data, length);
232 }
233
234 static void f_midi_handle_out_data(struct usb_ep *ep, struct usb_request *req)
235 {
236 unsigned int i;
237 u8 *buf = req->buf;
238
239 for (i = 0; i + 3 < req->actual; i += 4)
240 if (buf[i] != 0) {
241 int cable = buf[i] >> 4;
242 int length = f_midi_cin_length[buf[i] & 0x0f];
243 f_midi_read_data(ep, cable, &buf[i + 1], length);
244 }
245 }
246
247 static void
248 f_midi_complete(struct usb_ep *ep, struct usb_request *req)
249 {
250 struct f_midi *midi = ep->driver_data;
251 struct usb_composite_dev *cdev = midi->func.config->cdev;
252 int status = req->status;
253
254 switch (status) {
255 case 0: /* normal completion */
256 if (ep == midi->out_ep) {
257 /* We received stuff. req is queued again, below */
258 f_midi_handle_out_data(ep, req);
259 } else if (ep == midi->in_ep) {
260 /* Our transmit completed. See if there's more to go.
261 * f_midi_transmit eats req, don't queue it again. */
262 req->length = 0;
263 f_midi_transmit(midi);
264 return;
265 }
266 break;
267
268 /* this endpoint is normally active while we're configured */
269 case -ECONNABORTED: /* hardware forced ep reset */
270 case -ECONNRESET: /* request dequeued */
271 case -ESHUTDOWN: /* disconnect from host */
272 VDBG(cdev, "%s gone (%d), %d/%d\n", ep->name, status,
273 req->actual, req->length);
274 if (ep == midi->out_ep) {
275 f_midi_handle_out_data(ep, req);
276 /* We don't need to free IN requests because it's handled
277 * by the midi->in_req_fifo. */
278 free_ep_req(ep, req);
279 }
280 return;
281
282 case -EOVERFLOW: /* buffer overrun on read means that
283 * we didn't provide a big enough buffer.
284 */
285 default:
286 DBG(cdev, "%s complete --> %d, %d/%d\n", ep->name,
287 status, req->actual, req->length);
288 break;
289 case -EREMOTEIO: /* short read */
290 break;
291 }
292
293 status = usb_ep_queue(ep, req, GFP_ATOMIC);
294 if (status) {
295 ERROR(cdev, "kill %s: resubmit %d bytes --> %d\n",
296 ep->name, req->length, status);
297 usb_ep_set_halt(ep);
298 /* FIXME recover later ... somehow */
299 }
300 }
301
302 static int f_midi_start_ep(struct f_midi *midi,
303 struct usb_function *f,
304 struct usb_ep *ep)
305 {
306 int err;
307 struct usb_composite_dev *cdev = f->config->cdev;
308
309 usb_ep_disable(ep);
310
311 err = config_ep_by_speed(midi->gadget, f, ep);
312 if (err) {
313 ERROR(cdev, "can't configure %s: %d\n", ep->name, err);
314 return err;
315 }
316
317 err = usb_ep_enable(ep);
318 if (err) {
319 ERROR(cdev, "can't start %s: %d\n", ep->name, err);
320 return err;
321 }
322
323 ep->driver_data = midi;
324
325 return 0;
326 }
327
328 static int f_midi_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
329 {
330 struct f_midi *midi = func_to_midi(f);
331 unsigned i;
332 int err;
333
334 /* we only set alt for MIDIStreaming interface */
335 if (intf != midi->ms_id)
336 return 0;
337
338 err = f_midi_start_ep(midi, f, midi->in_ep);
339 if (err)
340 return err;
341
342 err = f_midi_start_ep(midi, f, midi->out_ep);
343 if (err)
344 return err;
345
346 /* pre-allocate write usb requests to use on f_midi_transmit. */
347 while (kfifo_avail(&midi->in_req_fifo)) {
348 struct usb_request *req =
349 midi_alloc_ep_req(midi->in_ep, midi->buflen);
350
351 if (req == NULL)
352 return -ENOMEM;
353
354 req->length = 0;
355 req->complete = f_midi_complete;
356
357 kfifo_put(&midi->in_req_fifo, req);
358 }
359
360 /* allocate a bunch of read buffers and queue them all at once. */
361 for (i = 0; i < midi->qlen && err == 0; i++) {
362 struct usb_request *req =
363 midi_alloc_ep_req(midi->out_ep,
364 max_t(unsigned, midi->buflen,
365 bulk_out_desc.wMaxPacketSize));
366 if (req == NULL)
367 return -ENOMEM;
368
369 req->complete = f_midi_complete;
370 err = usb_ep_queue(midi->out_ep, req, GFP_ATOMIC);
371 if (err) {
372 ERROR(midi, "%s: couldn't enqueue request: %d\n",
373 midi->out_ep->name, err);
374 free_ep_req(midi->out_ep, req);
375 return err;
376 }
377 }
378
379 return 0;
380 }
381
382 static void f_midi_disable(struct usb_function *f)
383 {
384 struct f_midi *midi = func_to_midi(f);
385 struct usb_composite_dev *cdev = f->config->cdev;
386 struct usb_request *req = NULL;
387
388 DBG(cdev, "disable\n");
389
390 /*
391 * just disable endpoints, forcing completion of pending i/o.
392 * all our completion handlers free their requests in this case.
393 */
394 usb_ep_disable(midi->in_ep);
395 usb_ep_disable(midi->out_ep);
396
397 /* release IN requests */
398 while (kfifo_get(&midi->in_req_fifo, &req))
399 free_ep_req(midi->in_ep, req);
400 }
401
402 static int f_midi_snd_free(struct snd_device *device)
403 {
404 return 0;
405 }
406
407 static void f_midi_transmit_packet(struct usb_request *req, uint8_t p0,
408 uint8_t p1, uint8_t p2, uint8_t p3)
409 {
410 unsigned length = req->length;
411 u8 *buf = (u8 *)req->buf + length;
412
413 buf[0] = p0;
414 buf[1] = p1;
415 buf[2] = p2;
416 buf[3] = p3;
417 req->length = length + 4;
418 }
419
420 /*
421 * Converts MIDI commands to USB MIDI packets.
422 */
423 static void f_midi_transmit_byte(struct usb_request *req,
424 struct gmidi_in_port *port, uint8_t b)
425 {
426 uint8_t p0 = port->cable << 4;
427
428 if (b >= 0xf8) {
429 f_midi_transmit_packet(req, p0 | 0x0f, b, 0, 0);
430 } else if (b >= 0xf0) {
431 switch (b) {
432 case 0xf0:
433 port->data[0] = b;
434 port->state = STATE_SYSEX_1;
435 break;
436 case 0xf1:
437 case 0xf3:
438 port->data[0] = b;
439 port->state = STATE_1PARAM;
440 break;
441 case 0xf2:
442 port->data[0] = b;
443 port->state = STATE_2PARAM_1;
444 break;
445 case 0xf4:
446 case 0xf5:
447 port->state = STATE_UNKNOWN;
448 break;
449 case 0xf6:
450 f_midi_transmit_packet(req, p0 | 0x05, 0xf6, 0, 0);
451 port->state = STATE_UNKNOWN;
452 break;
453 case 0xf7:
454 switch (port->state) {
455 case STATE_SYSEX_0:
456 f_midi_transmit_packet(req,
457 p0 | 0x05, 0xf7, 0, 0);
458 break;
459 case STATE_SYSEX_1:
460 f_midi_transmit_packet(req,
461 p0 | 0x06, port->data[0], 0xf7, 0);
462 break;
463 case STATE_SYSEX_2:
464 f_midi_transmit_packet(req,
465 p0 | 0x07, port->data[0],
466 port->data[1], 0xf7);
467 break;
468 }
469 port->state = STATE_UNKNOWN;
470 break;
471 }
472 } else if (b >= 0x80) {
473 port->data[0] = b;
474 if (b >= 0xc0 && b <= 0xdf)
475 port->state = STATE_1PARAM;
476 else
477 port->state = STATE_2PARAM_1;
478 } else { /* b < 0x80 */
479 switch (port->state) {
480 case STATE_1PARAM:
481 if (port->data[0] < 0xf0) {
482 p0 |= port->data[0] >> 4;
483 } else {
484 p0 |= 0x02;
485 port->state = STATE_UNKNOWN;
486 }
487 f_midi_transmit_packet(req, p0, port->data[0], b, 0);
488 break;
489 case STATE_2PARAM_1:
490 port->data[1] = b;
491 port->state = STATE_2PARAM_2;
492 break;
493 case STATE_2PARAM_2:
494 if (port->data[0] < 0xf0) {
495 p0 |= port->data[0] >> 4;
496 port->state = STATE_2PARAM_1;
497 } else {
498 p0 |= 0x03;
499 port->state = STATE_UNKNOWN;
500 }
501 f_midi_transmit_packet(req,
502 p0, port->data[0], port->data[1], b);
503 break;
504 case STATE_SYSEX_0:
505 port->data[0] = b;
506 port->state = STATE_SYSEX_1;
507 break;
508 case STATE_SYSEX_1:
509 port->data[1] = b;
510 port->state = STATE_SYSEX_2;
511 break;
512 case STATE_SYSEX_2:
513 f_midi_transmit_packet(req,
514 p0 | 0x04, port->data[0], port->data[1], b);
515 port->state = STATE_SYSEX_0;
516 break;
517 }
518 }
519 }
520
521 static void f_midi_drop_out_substreams(struct f_midi *midi)
522 {
523 unsigned int i;
524
525 for (i = 0; i < midi->in_ports; i++) {
526 struct gmidi_in_port *port = midi->in_ports_array + i;
527 struct snd_rawmidi_substream *substream = port->substream;
528 if (port->active && substream)
529 snd_rawmidi_drop_output(substream);
530 }
531 }
532
533 static int f_midi_do_transmit(struct f_midi *midi, struct usb_ep *ep)
534 {
535 struct usb_request *req = NULL;
536 unsigned int len, i;
537 bool active = false;
538 int err;
539
540 /*
541 * We peek the request in order to reuse it if it fails to enqueue on
542 * its endpoint
543 */
544 len = kfifo_peek(&midi->in_req_fifo, &req);
545 if (len != 1) {
546 ERROR(midi, "%s: Couldn't get usb request\n", __func__);
547 return -1;
548 }
549
550 /*
551 * If buffer overrun, then we ignore this transmission.
552 * IMPORTANT: This will cause the user-space rawmidi device to block
553 * until a) usb requests have been completed or b) snd_rawmidi_write()
554 * times out.
555 */
556 if (req->length > 0)
557 return 0;
558
559 for (i = midi->in_last_port; i < midi->in_ports; ++i) {
560 struct gmidi_in_port *port = midi->in_ports_array + i;
561 struct snd_rawmidi_substream *substream = port->substream;
562
563 if (!port->active || !substream)
564 continue;
565
566 while (req->length + 3 < midi->buflen) {
567 uint8_t b;
568
569 if (snd_rawmidi_transmit(substream, &b, 1) != 1) {
570 port->active = 0;
571 break;
572 }
573 f_midi_transmit_byte(req, port, b);
574 }
575
576 active = !!port->active;
577 if (active)
578 break;
579 }
580 midi->in_last_port = active ? i : 0;
581
582 if (req->length <= 0)
583 goto done;
584
585 err = usb_ep_queue(ep, req, GFP_ATOMIC);
586 if (err < 0) {
587 ERROR(midi, "%s failed to queue req: %d\n",
588 midi->in_ep->name, err);
589 req->length = 0; /* Re-use request next time. */
590 } else {
591 /* Upon success, put request at the back of the queue. */
592 kfifo_skip(&midi->in_req_fifo);
593 kfifo_put(&midi->in_req_fifo, req);
594 }
595
596 done:
597 return active;
598 }
599
600 static void f_midi_transmit(struct f_midi *midi)
601 {
602 struct usb_ep *ep = midi->in_ep;
603 int ret;
604 unsigned long flags;
605
606 /* We only care about USB requests if IN endpoint is enabled */
607 if (!ep || !ep->enabled)
608 goto drop_out;
609
610 spin_lock_irqsave(&midi->transmit_lock, flags);
611
612 do {
613 ret = f_midi_do_transmit(midi, ep);
614 if (ret < 0) {
615 spin_unlock_irqrestore(&midi->transmit_lock, flags);
616 goto drop_out;
617 }
618 } while (ret);
619
620 spin_unlock_irqrestore(&midi->transmit_lock, flags);
621
622 return;
623
624 drop_out:
625 f_midi_drop_out_substreams(midi);
626 }
627
628 static void f_midi_in_tasklet(unsigned long data)
629 {
630 struct f_midi *midi = (struct f_midi *) data;
631 f_midi_transmit(midi);
632 }
633
634 static int f_midi_in_open(struct snd_rawmidi_substream *substream)
635 {
636 struct f_midi *midi = substream->rmidi->private_data;
637 struct gmidi_in_port *port;
638
639 if (substream->number >= midi->in_ports)
640 return -EINVAL;
641
642 VDBG(midi, "%s()\n", __func__);
643 port = midi->in_ports_array + substream->number;
644 port->substream = substream;
645 port->state = STATE_UNKNOWN;
646 return 0;
647 }
648
649 static int f_midi_in_close(struct snd_rawmidi_substream *substream)
650 {
651 struct f_midi *midi = substream->rmidi->private_data;
652
653 VDBG(midi, "%s()\n", __func__);
654 return 0;
655 }
656
657 static void f_midi_in_trigger(struct snd_rawmidi_substream *substream, int up)
658 {
659 struct f_midi *midi = substream->rmidi->private_data;
660
661 if (substream->number >= midi->in_ports)
662 return;
663
664 VDBG(midi, "%s() %d\n", __func__, up);
665 midi->in_ports_array[substream->number].active = up;
666 if (up)
667 tasklet_hi_schedule(&midi->tasklet);
668 }
669
670 static int f_midi_out_open(struct snd_rawmidi_substream *substream)
671 {
672 struct f_midi *midi = substream->rmidi->private_data;
673
674 if (substream->number >= MAX_PORTS)
675 return -EINVAL;
676
677 VDBG(midi, "%s()\n", __func__);
678 midi->out_substream[substream->number] = substream;
679 return 0;
680 }
681
682 static int f_midi_out_close(struct snd_rawmidi_substream *substream)
683 {
684 struct f_midi *midi = substream->rmidi->private_data;
685
686 VDBG(midi, "%s()\n", __func__);
687 return 0;
688 }
689
690 static void f_midi_out_trigger(struct snd_rawmidi_substream *substream, int up)
691 {
692 struct f_midi *midi = substream->rmidi->private_data;
693
694 VDBG(midi, "%s()\n", __func__);
695
696 if (up)
697 set_bit(substream->number, &midi->out_triggered);
698 else
699 clear_bit(substream->number, &midi->out_triggered);
700 }
701
702 static struct snd_rawmidi_ops gmidi_in_ops = {
703 .open = f_midi_in_open,
704 .close = f_midi_in_close,
705 .trigger = f_midi_in_trigger,
706 };
707
708 static struct snd_rawmidi_ops gmidi_out_ops = {
709 .open = f_midi_out_open,
710 .close = f_midi_out_close,
711 .trigger = f_midi_out_trigger
712 };
713
714 static inline void f_midi_unregister_card(struct f_midi *midi)
715 {
716 if (midi->card) {
717 snd_card_free(midi->card);
718 midi->card = NULL;
719 }
720 }
721
722 /* register as a sound "card" */
723 static int f_midi_register_card(struct f_midi *midi)
724 {
725 struct snd_card *card;
726 struct snd_rawmidi *rmidi;
727 int err;
728 static struct snd_device_ops ops = {
729 .dev_free = f_midi_snd_free,
730 };
731
732 err = snd_card_new(&midi->gadget->dev, midi->index, midi->id,
733 THIS_MODULE, 0, &card);
734 if (err < 0) {
735 ERROR(midi, "snd_card_new() failed\n");
736 goto fail;
737 }
738 midi->card = card;
739
740 err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, midi, &ops);
741 if (err < 0) {
742 ERROR(midi, "snd_device_new() failed: error %d\n", err);
743 goto fail;
744 }
745
746 strcpy(card->driver, f_midi_longname);
747 strcpy(card->longname, f_midi_longname);
748 strcpy(card->shortname, f_midi_shortname);
749
750 /* Set up rawmidi */
751 snd_component_add(card, "MIDI");
752 err = snd_rawmidi_new(card, card->longname, 0,
753 midi->out_ports, midi->in_ports, &rmidi);
754 if (err < 0) {
755 ERROR(midi, "snd_rawmidi_new() failed: error %d\n", err);
756 goto fail;
757 }
758 midi->rmidi = rmidi;
759 midi->in_last_port = 0;
760 strcpy(rmidi->name, card->shortname);
761 rmidi->info_flags = SNDRV_RAWMIDI_INFO_OUTPUT |
762 SNDRV_RAWMIDI_INFO_INPUT |
763 SNDRV_RAWMIDI_INFO_DUPLEX;
764 rmidi->private_data = midi;
765
766 /*
767 * Yes, rawmidi OUTPUT = USB IN, and rawmidi INPUT = USB OUT.
768 * It's an upside-down world being a gadget.
769 */
770 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, &gmidi_in_ops);
771 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, &gmidi_out_ops);
772
773 /* register it - we're ready to go */
774 err = snd_card_register(card);
775 if (err < 0) {
776 ERROR(midi, "snd_card_register() failed\n");
777 goto fail;
778 }
779
780 VDBG(midi, "%s() finished ok\n", __func__);
781 return 0;
782
783 fail:
784 f_midi_unregister_card(midi);
785 return err;
786 }
787
788 /* MIDI function driver setup/binding */
789
790 static int f_midi_bind(struct usb_configuration *c, struct usb_function *f)
791 {
792 struct usb_descriptor_header **midi_function;
793 struct usb_midi_in_jack_descriptor jack_in_ext_desc[MAX_PORTS];
794 struct usb_midi_in_jack_descriptor jack_in_emb_desc[MAX_PORTS];
795 struct usb_midi_out_jack_descriptor_1 jack_out_ext_desc[MAX_PORTS];
796 struct usb_midi_out_jack_descriptor_1 jack_out_emb_desc[MAX_PORTS];
797 struct usb_composite_dev *cdev = c->cdev;
798 struct f_midi *midi = func_to_midi(f);
799 struct usb_string *us;
800 int status, n, jack = 1, i = 0;
801
802 midi->gadget = cdev->gadget;
803 tasklet_init(&midi->tasklet, f_midi_in_tasklet, (unsigned long) midi);
804 status = f_midi_register_card(midi);
805 if (status < 0)
806 goto fail_register;
807
808 /* maybe allocate device-global string ID */
809 us = usb_gstrings_attach(c->cdev, midi_strings,
810 ARRAY_SIZE(midi_string_defs));
811 if (IS_ERR(us)) {
812 status = PTR_ERR(us);
813 goto fail;
814 }
815 ac_interface_desc.iInterface = us[STRING_FUNC_IDX].id;
816
817 /* We have two interfaces, AudioControl and MIDIStreaming */
818 status = usb_interface_id(c, f);
819 if (status < 0)
820 goto fail;
821 ac_interface_desc.bInterfaceNumber = status;
822
823 status = usb_interface_id(c, f);
824 if (status < 0)
825 goto fail;
826 ms_interface_desc.bInterfaceNumber = status;
827 ac_header_desc.baInterfaceNr[0] = status;
828 midi->ms_id = status;
829
830 status = -ENODEV;
831
832 /* allocate instance-specific endpoints */
833 midi->in_ep = usb_ep_autoconfig(cdev->gadget, &bulk_in_desc);
834 if (!midi->in_ep)
835 goto fail;
836
837 midi->out_ep = usb_ep_autoconfig(cdev->gadget, &bulk_out_desc);
838 if (!midi->out_ep)
839 goto fail;
840
841 /* allocate temporary function list */
842 midi_function = kcalloc((MAX_PORTS * 4) + 9, sizeof(*midi_function),
843 GFP_KERNEL);
844 if (!midi_function) {
845 status = -ENOMEM;
846 goto fail;
847 }
848
849 /*
850 * construct the function's descriptor set. As the number of
851 * input and output MIDI ports is configurable, we have to do
852 * it that way.
853 */
854
855 /* add the headers - these are always the same */
856 midi_function[i++] = (struct usb_descriptor_header *) &ac_interface_desc;
857 midi_function[i++] = (struct usb_descriptor_header *) &ac_header_desc;
858 midi_function[i++] = (struct usb_descriptor_header *) &ms_interface_desc;
859
860 /* calculate the header's wTotalLength */
861 n = USB_DT_MS_HEADER_SIZE
862 + (midi->in_ports + midi->out_ports) *
863 (USB_DT_MIDI_IN_SIZE + USB_DT_MIDI_OUT_SIZE(1));
864 ms_header_desc.wTotalLength = cpu_to_le16(n);
865
866 midi_function[i++] = (struct usb_descriptor_header *) &ms_header_desc;
867
868 /* configure the external IN jacks, each linked to an embedded OUT jack */
869 for (n = 0; n < midi->in_ports; n++) {
870 struct usb_midi_in_jack_descriptor *in_ext = &jack_in_ext_desc[n];
871 struct usb_midi_out_jack_descriptor_1 *out_emb = &jack_out_emb_desc[n];
872
873 in_ext->bLength = USB_DT_MIDI_IN_SIZE;
874 in_ext->bDescriptorType = USB_DT_CS_INTERFACE;
875 in_ext->bDescriptorSubtype = USB_MS_MIDI_IN_JACK;
876 in_ext->bJackType = USB_MS_EXTERNAL;
877 in_ext->bJackID = jack++;
878 in_ext->iJack = 0;
879 midi_function[i++] = (struct usb_descriptor_header *) in_ext;
880
881 out_emb->bLength = USB_DT_MIDI_OUT_SIZE(1);
882 out_emb->bDescriptorType = USB_DT_CS_INTERFACE;
883 out_emb->bDescriptorSubtype = USB_MS_MIDI_OUT_JACK;
884 out_emb->bJackType = USB_MS_EMBEDDED;
885 out_emb->bJackID = jack++;
886 out_emb->bNrInputPins = 1;
887 out_emb->pins[0].baSourcePin = 1;
888 out_emb->pins[0].baSourceID = in_ext->bJackID;
889 out_emb->iJack = 0;
890 midi_function[i++] = (struct usb_descriptor_header *) out_emb;
891
892 /* link it to the endpoint */
893 ms_in_desc.baAssocJackID[n] = out_emb->bJackID;
894 }
895
896 /* configure the external OUT jacks, each linked to an embedded IN jack */
897 for (n = 0; n < midi->out_ports; n++) {
898 struct usb_midi_in_jack_descriptor *in_emb = &jack_in_emb_desc[n];
899 struct usb_midi_out_jack_descriptor_1 *out_ext = &jack_out_ext_desc[n];
900
901 in_emb->bLength = USB_DT_MIDI_IN_SIZE;
902 in_emb->bDescriptorType = USB_DT_CS_INTERFACE;
903 in_emb->bDescriptorSubtype = USB_MS_MIDI_IN_JACK;
904 in_emb->bJackType = USB_MS_EMBEDDED;
905 in_emb->bJackID = jack++;
906 in_emb->iJack = 0;
907 midi_function[i++] = (struct usb_descriptor_header *) in_emb;
908
909 out_ext->bLength = USB_DT_MIDI_OUT_SIZE(1);
910 out_ext->bDescriptorType = USB_DT_CS_INTERFACE;
911 out_ext->bDescriptorSubtype = USB_MS_MIDI_OUT_JACK;
912 out_ext->bJackType = USB_MS_EXTERNAL;
913 out_ext->bJackID = jack++;
914 out_ext->bNrInputPins = 1;
915 out_ext->iJack = 0;
916 out_ext->pins[0].baSourceID = in_emb->bJackID;
917 out_ext->pins[0].baSourcePin = 1;
918 midi_function[i++] = (struct usb_descriptor_header *) out_ext;
919
920 /* link it to the endpoint */
921 ms_out_desc.baAssocJackID[n] = in_emb->bJackID;
922 }
923
924 /* configure the endpoint descriptors ... */
925 ms_out_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->in_ports);
926 ms_out_desc.bNumEmbMIDIJack = midi->in_ports;
927
928 ms_in_desc.bLength = USB_DT_MS_ENDPOINT_SIZE(midi->out_ports);
929 ms_in_desc.bNumEmbMIDIJack = midi->out_ports;
930
931 /* ... and add them to the list */
932 midi_function[i++] = (struct usb_descriptor_header *) &bulk_out_desc;
933 midi_function[i++] = (struct usb_descriptor_header *) &ms_out_desc;
934 midi_function[i++] = (struct usb_descriptor_header *) &bulk_in_desc;
935 midi_function[i++] = (struct usb_descriptor_header *) &ms_in_desc;
936 midi_function[i++] = NULL;
937
938 /*
939 * support all relevant hardware speeds... we expect that when
940 * hardware is dual speed, all bulk-capable endpoints work at
941 * both speeds
942 */
943 /* copy descriptors, and track endpoint copies */
944 f->fs_descriptors = usb_copy_descriptors(midi_function);
945 if (!f->fs_descriptors)
946 goto fail_f_midi;
947
948 if (gadget_is_dualspeed(c->cdev->gadget)) {
949 bulk_in_desc.wMaxPacketSize = cpu_to_le16(512);
950 bulk_out_desc.wMaxPacketSize = cpu_to_le16(512);
951 f->hs_descriptors = usb_copy_descriptors(midi_function);
952 if (!f->hs_descriptors)
953 goto fail_f_midi;
954 }
955
956 kfree(midi_function);
957
958 return 0;
959
960 fail_f_midi:
961 kfree(midi_function);
962 usb_free_descriptors(f->hs_descriptors);
963 fail:
964 f_midi_unregister_card(midi);
965 fail_register:
966 ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
967
968 return status;
969 }
970
971 static inline struct f_midi_opts *to_f_midi_opts(struct config_item *item)
972 {
973 return container_of(to_config_group(item), struct f_midi_opts,
974 func_inst.group);
975 }
976
977 static void midi_attr_release(struct config_item *item)
978 {
979 struct f_midi_opts *opts = to_f_midi_opts(item);
980
981 usb_put_function_instance(&opts->func_inst);
982 }
983
984 static struct configfs_item_operations midi_item_ops = {
985 .release = midi_attr_release,
986 };
987
988 #define F_MIDI_OPT(name, test_limit, limit) \
989 static ssize_t f_midi_opts_##name##_show(struct config_item *item, char *page) \
990 { \
991 struct f_midi_opts *opts = to_f_midi_opts(item); \
992 int result; \
993 \
994 mutex_lock(&opts->lock); \
995 result = sprintf(page, "%d\n", opts->name); \
996 mutex_unlock(&opts->lock); \
997 \
998 return result; \
999 } \
1000 \
1001 static ssize_t f_midi_opts_##name##_store(struct config_item *item, \
1002 const char *page, size_t len) \
1003 { \
1004 struct f_midi_opts *opts = to_f_midi_opts(item); \
1005 int ret; \
1006 u32 num; \
1007 \
1008 mutex_lock(&opts->lock); \
1009 if (opts->refcnt) { \
1010 ret = -EBUSY; \
1011 goto end; \
1012 } \
1013 \
1014 ret = kstrtou32(page, 0, &num); \
1015 if (ret) \
1016 goto end; \
1017 \
1018 if (test_limit && num > limit) { \
1019 ret = -EINVAL; \
1020 goto end; \
1021 } \
1022 opts->name = num; \
1023 ret = len; \
1024 \
1025 end: \
1026 mutex_unlock(&opts->lock); \
1027 return ret; \
1028 } \
1029 \
1030 CONFIGFS_ATTR(f_midi_opts_, name);
1031
1032 F_MIDI_OPT(index, true, SNDRV_CARDS);
1033 F_MIDI_OPT(buflen, false, 0);
1034 F_MIDI_OPT(qlen, false, 0);
1035 F_MIDI_OPT(in_ports, true, MAX_PORTS);
1036 F_MIDI_OPT(out_ports, true, MAX_PORTS);
1037
1038 static ssize_t f_midi_opts_id_show(struct config_item *item, char *page)
1039 {
1040 struct f_midi_opts *opts = to_f_midi_opts(item);
1041 int result;
1042
1043 mutex_lock(&opts->lock);
1044 if (opts->id) {
1045 result = strlcpy(page, opts->id, PAGE_SIZE);
1046 } else {
1047 page[0] = 0;
1048 result = 0;
1049 }
1050
1051 mutex_unlock(&opts->lock);
1052
1053 return result;
1054 }
1055
1056 static ssize_t f_midi_opts_id_store(struct config_item *item,
1057 const char *page, size_t len)
1058 {
1059 struct f_midi_opts *opts = to_f_midi_opts(item);
1060 int ret;
1061 char *c;
1062
1063 mutex_lock(&opts->lock);
1064 if (opts->refcnt) {
1065 ret = -EBUSY;
1066 goto end;
1067 }
1068
1069 c = kstrndup(page, len, GFP_KERNEL);
1070 if (!c) {
1071 ret = -ENOMEM;
1072 goto end;
1073 }
1074 if (opts->id_allocated)
1075 kfree(opts->id);
1076 opts->id = c;
1077 opts->id_allocated = true;
1078 ret = len;
1079 end:
1080 mutex_unlock(&opts->lock);
1081 return ret;
1082 }
1083
1084 CONFIGFS_ATTR(f_midi_opts_, id);
1085
1086 static struct configfs_attribute *midi_attrs[] = {
1087 &f_midi_opts_attr_index,
1088 &f_midi_opts_attr_buflen,
1089 &f_midi_opts_attr_qlen,
1090 &f_midi_opts_attr_in_ports,
1091 &f_midi_opts_attr_out_ports,
1092 &f_midi_opts_attr_id,
1093 NULL,
1094 };
1095
1096 static struct config_item_type midi_func_type = {
1097 .ct_item_ops = &midi_item_ops,
1098 .ct_attrs = midi_attrs,
1099 .ct_owner = THIS_MODULE,
1100 };
1101
1102 static void f_midi_free_inst(struct usb_function_instance *f)
1103 {
1104 struct f_midi_opts *opts;
1105
1106 opts = container_of(f, struct f_midi_opts, func_inst);
1107
1108 if (opts->id_allocated)
1109 kfree(opts->id);
1110
1111 kfree(opts);
1112 }
1113
1114 static struct usb_function_instance *f_midi_alloc_inst(void)
1115 {
1116 struct f_midi_opts *opts;
1117
1118 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1119 if (!opts)
1120 return ERR_PTR(-ENOMEM);
1121
1122 mutex_init(&opts->lock);
1123 opts->func_inst.free_func_inst = f_midi_free_inst;
1124 opts->index = SNDRV_DEFAULT_IDX1;
1125 opts->id = SNDRV_DEFAULT_STR1;
1126 opts->buflen = 256;
1127 opts->qlen = 32;
1128 opts->in_ports = 1;
1129 opts->out_ports = 1;
1130
1131 config_group_init_type_name(&opts->func_inst.group, "",
1132 &midi_func_type);
1133
1134 return &opts->func_inst;
1135 }
1136
1137 static void f_midi_free(struct usb_function *f)
1138 {
1139 struct f_midi *midi;
1140 struct f_midi_opts *opts;
1141
1142 midi = func_to_midi(f);
1143 opts = container_of(f->fi, struct f_midi_opts, func_inst);
1144 kfree(midi->id);
1145 mutex_lock(&opts->lock);
1146 kfifo_free(&midi->in_req_fifo);
1147 kfree(midi);
1148 --opts->refcnt;
1149 mutex_unlock(&opts->lock);
1150 }
1151
1152 static void f_midi_unbind(struct usb_configuration *c, struct usb_function *f)
1153 {
1154 struct usb_composite_dev *cdev = f->config->cdev;
1155 struct f_midi *midi = func_to_midi(f);
1156 struct snd_card *card;
1157
1158 DBG(cdev, "unbind\n");
1159
1160 /* just to be sure */
1161 f_midi_disable(f);
1162
1163 card = midi->card;
1164 midi->card = NULL;
1165 if (card)
1166 snd_card_free(card);
1167
1168 usb_free_all_descriptors(f);
1169 }
1170
1171 static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)
1172 {
1173 struct f_midi *midi = NULL;
1174 struct f_midi_opts *opts;
1175 int status, i;
1176
1177 opts = container_of(fi, struct f_midi_opts, func_inst);
1178
1179 mutex_lock(&opts->lock);
1180 /* sanity check */
1181 if (opts->in_ports > MAX_PORTS || opts->out_ports > MAX_PORTS) {
1182 status = -EINVAL;
1183 goto setup_fail;
1184 }
1185
1186 /* allocate and initialize one new instance */
1187 midi = kzalloc(
1188 sizeof(*midi) + opts->in_ports * sizeof(*midi->in_ports_array),
1189 GFP_KERNEL);
1190 if (!midi) {
1191 status = -ENOMEM;
1192 goto setup_fail;
1193 }
1194
1195 for (i = 0; i < opts->in_ports; i++)
1196 midi->in_ports_array[i].cable = i;
1197
1198 /* set up ALSA midi devices */
1199 midi->id = kstrdup(opts->id, GFP_KERNEL);
1200 if (opts->id && !midi->id) {
1201 status = -ENOMEM;
1202 goto setup_fail;
1203 }
1204 midi->in_ports = opts->in_ports;
1205 midi->out_ports = opts->out_ports;
1206 midi->index = opts->index;
1207 midi->buflen = opts->buflen;
1208 midi->qlen = opts->qlen;
1209 midi->in_last_port = 0;
1210
1211 status = kfifo_alloc(&midi->in_req_fifo, midi->qlen, GFP_KERNEL);
1212 if (status)
1213 goto setup_fail;
1214
1215 spin_lock_init(&midi->transmit_lock);
1216
1217 ++opts->refcnt;
1218 mutex_unlock(&opts->lock);
1219
1220 midi->func.name = "gmidi function";
1221 midi->func.bind = f_midi_bind;
1222 midi->func.unbind = f_midi_unbind;
1223 midi->func.set_alt = f_midi_set_alt;
1224 midi->func.disable = f_midi_disable;
1225 midi->func.free_func = f_midi_free;
1226
1227 return &midi->func;
1228
1229 setup_fail:
1230 mutex_unlock(&opts->lock);
1231 kfree(midi);
1232 return ERR_PTR(status);
1233 }
1234
1235 DECLARE_USB_FUNCTION_INIT(midi, f_midi_alloc_inst, f_midi_alloc);
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