1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Behringer BCD2000 driver |
4 | * |
5 | * Copyright (C) 2014 Mario Kicherer (dev@kicherer.org) |
6 | */ |
7 | |
8 | #include <linux/kernel.h> |
9 | #include <linux/errno.h> |
10 | #include <linux/init.h> |
11 | #include <linux/slab.h> |
12 | #include <linux/module.h> |
13 | #include <linux/bitmap.h> |
14 | #include <linux/usb.h> |
15 | #include <linux/usb/audio.h> |
16 | #include <sound/core.h> |
17 | #include <sound/initval.h> |
18 | #include <sound/rawmidi.h> |
19 | |
20 | #define PREFIX "snd-bcd2000: " |
21 | #define BUFSIZE 64 |
22 | |
23 | static const struct usb_device_id id_table[] = { |
24 | { USB_DEVICE(0x1397, 0x00bd) }, |
25 | { }, |
26 | }; |
27 | |
28 | static const unsigned char device_cmd_prefix[] = {0x03, 0x00}; |
29 | |
30 | static const unsigned char bcd2000_init_sequence[] = { |
31 | 0x07, 0x00, 0x00, 0x00, 0x78, 0x48, 0x1c, 0x81, |
32 | 0xc4, 0x00, 0x00, 0x00, 0x5e, 0x53, 0x4a, 0xf7, |
33 | 0x18, 0xfa, 0x11, 0xff, 0x6c, 0xf3, 0x90, 0xff, |
34 | 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, |
35 | 0x18, 0xfa, 0x11, 0xff, 0x14, 0x00, 0x00, 0x00, |
36 | 0x00, 0x00, 0x00, 0x00, 0xf2, 0x34, 0x4a, 0xf7, |
37 | 0x18, 0xfa, 0x11, 0xff |
38 | }; |
39 | |
40 | struct bcd2000 { |
41 | struct usb_device *dev; |
42 | struct snd_card *card; |
43 | struct usb_interface *intf; |
44 | int card_index; |
45 | |
46 | int midi_out_active; |
47 | struct snd_rawmidi *rmidi; |
48 | struct snd_rawmidi_substream *midi_receive_substream; |
49 | struct snd_rawmidi_substream *midi_out_substream; |
50 | |
51 | unsigned char midi_in_buf[BUFSIZE]; |
52 | unsigned char midi_out_buf[BUFSIZE]; |
53 | |
54 | struct urb *midi_out_urb; |
55 | struct urb *midi_in_urb; |
56 | |
57 | struct usb_anchor anchor; |
58 | }; |
59 | |
60 | static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; |
61 | static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; |
62 | |
63 | static DEFINE_MUTEX(devices_mutex); |
64 | static DECLARE_BITMAP(devices_used, SNDRV_CARDS); |
65 | static struct usb_driver bcd2000_driver; |
66 | |
67 | #ifdef CONFIG_SND_DEBUG |
68 | static void bcd2000_dump_buffer(const char *prefix, const char *buf, int len) |
69 | { |
70 | print_hex_dump(KERN_DEBUG, prefix_str: prefix, |
71 | prefix_type: DUMP_PREFIX_NONE, rowsize: 16, groupsize: 1, |
72 | buf, len, ascii: false); |
73 | } |
74 | #else |
75 | static void bcd2000_dump_buffer(const char *prefix, const char *buf, int len) {} |
76 | #endif |
77 | |
78 | static int bcd2000_midi_input_open(struct snd_rawmidi_substream *substream) |
79 | { |
80 | return 0; |
81 | } |
82 | |
83 | static int bcd2000_midi_input_close(struct snd_rawmidi_substream *substream) |
84 | { |
85 | return 0; |
86 | } |
87 | |
88 | /* (de)register midi substream from client */ |
89 | static void bcd2000_midi_input_trigger(struct snd_rawmidi_substream *substream, |
90 | int up) |
91 | { |
92 | struct bcd2000 *bcd2k = substream->rmidi->private_data; |
93 | bcd2k->midi_receive_substream = up ? substream : NULL; |
94 | } |
95 | |
96 | static void bcd2000_midi_handle_input(struct bcd2000 *bcd2k, |
97 | const unsigned char *buf, unsigned int buf_len) |
98 | { |
99 | unsigned int payload_length, tocopy; |
100 | struct snd_rawmidi_substream *midi_receive_substream; |
101 | |
102 | midi_receive_substream = READ_ONCE(bcd2k->midi_receive_substream); |
103 | if (!midi_receive_substream) |
104 | return; |
105 | |
106 | bcd2000_dump_buffer(PREFIX "received from device: " , buf, len: buf_len); |
107 | |
108 | if (buf_len < 2) |
109 | return; |
110 | |
111 | payload_length = buf[0]; |
112 | |
113 | /* ignore packets without payload */ |
114 | if (payload_length == 0) |
115 | return; |
116 | |
117 | tocopy = min(payload_length, buf_len-1); |
118 | |
119 | bcd2000_dump_buffer(PREFIX "sending to userspace: " , |
120 | buf: &buf[1], len: tocopy); |
121 | |
122 | snd_rawmidi_receive(substream: midi_receive_substream, |
123 | buffer: &buf[1], count: tocopy); |
124 | } |
125 | |
126 | static void bcd2000_midi_send(struct bcd2000 *bcd2k) |
127 | { |
128 | int len, ret; |
129 | struct snd_rawmidi_substream *midi_out_substream; |
130 | |
131 | BUILD_BUG_ON(sizeof(device_cmd_prefix) >= BUFSIZE); |
132 | |
133 | midi_out_substream = READ_ONCE(bcd2k->midi_out_substream); |
134 | if (!midi_out_substream) |
135 | return; |
136 | |
137 | /* copy command prefix bytes */ |
138 | memcpy(bcd2k->midi_out_buf, device_cmd_prefix, |
139 | sizeof(device_cmd_prefix)); |
140 | |
141 | /* |
142 | * get MIDI packet and leave space for command prefix |
143 | * and payload length |
144 | */ |
145 | len = snd_rawmidi_transmit(substream: midi_out_substream, |
146 | buffer: bcd2k->midi_out_buf + 3, BUFSIZE - 3); |
147 | |
148 | if (len < 0) |
149 | dev_err(&bcd2k->dev->dev, "%s: snd_rawmidi_transmit error %d\n" , |
150 | __func__, len); |
151 | |
152 | if (len <= 0) |
153 | return; |
154 | |
155 | /* set payload length */ |
156 | bcd2k->midi_out_buf[2] = len; |
157 | bcd2k->midi_out_urb->transfer_buffer_length = BUFSIZE; |
158 | |
159 | bcd2000_dump_buffer(PREFIX "sending to device: " , |
160 | buf: bcd2k->midi_out_buf, len: len+3); |
161 | |
162 | /* send packet to the BCD2000 */ |
163 | ret = usb_submit_urb(urb: bcd2k->midi_out_urb, GFP_ATOMIC); |
164 | if (ret < 0) |
165 | dev_err(&bcd2k->dev->dev, PREFIX |
166 | "%s (%p): usb_submit_urb() failed, ret=%d, len=%d\n" , |
167 | __func__, midi_out_substream, ret, len); |
168 | else |
169 | bcd2k->midi_out_active = 1; |
170 | } |
171 | |
172 | static int bcd2000_midi_output_open(struct snd_rawmidi_substream *substream) |
173 | { |
174 | return 0; |
175 | } |
176 | |
177 | static int bcd2000_midi_output_close(struct snd_rawmidi_substream *substream) |
178 | { |
179 | struct bcd2000 *bcd2k = substream->rmidi->private_data; |
180 | |
181 | if (bcd2k->midi_out_active) { |
182 | usb_kill_urb(urb: bcd2k->midi_out_urb); |
183 | bcd2k->midi_out_active = 0; |
184 | } |
185 | |
186 | return 0; |
187 | } |
188 | |
189 | /* (de)register midi substream from client */ |
190 | static void bcd2000_midi_output_trigger(struct snd_rawmidi_substream *substream, |
191 | int up) |
192 | { |
193 | struct bcd2000 *bcd2k = substream->rmidi->private_data; |
194 | |
195 | if (up) { |
196 | bcd2k->midi_out_substream = substream; |
197 | /* check if there is data userspace wants to send */ |
198 | if (!bcd2k->midi_out_active) |
199 | bcd2000_midi_send(bcd2k); |
200 | } else { |
201 | bcd2k->midi_out_substream = NULL; |
202 | } |
203 | } |
204 | |
205 | static void bcd2000_output_complete(struct urb *urb) |
206 | { |
207 | struct bcd2000 *bcd2k = urb->context; |
208 | |
209 | bcd2k->midi_out_active = 0; |
210 | |
211 | if (urb->status) |
212 | dev_warn(&urb->dev->dev, |
213 | PREFIX "output urb->status: %d\n" , urb->status); |
214 | |
215 | if (urb->status == -ESHUTDOWN) |
216 | return; |
217 | |
218 | /* check if there is more data userspace wants to send */ |
219 | bcd2000_midi_send(bcd2k); |
220 | } |
221 | |
222 | static void bcd2000_input_complete(struct urb *urb) |
223 | { |
224 | int ret; |
225 | struct bcd2000 *bcd2k = urb->context; |
226 | |
227 | if (urb->status) |
228 | dev_warn(&urb->dev->dev, |
229 | PREFIX "input urb->status: %i\n" , urb->status); |
230 | |
231 | if (!bcd2k || urb->status == -ESHUTDOWN) |
232 | return; |
233 | |
234 | if (urb->actual_length > 0) |
235 | bcd2000_midi_handle_input(bcd2k, buf: urb->transfer_buffer, |
236 | buf_len: urb->actual_length); |
237 | |
238 | /* return URB to device */ |
239 | ret = usb_submit_urb(urb: bcd2k->midi_in_urb, GFP_ATOMIC); |
240 | if (ret < 0) |
241 | dev_err(&bcd2k->dev->dev, PREFIX |
242 | "%s: usb_submit_urb() failed, ret=%d\n" , |
243 | __func__, ret); |
244 | } |
245 | |
246 | static const struct snd_rawmidi_ops bcd2000_midi_output = { |
247 | .open = bcd2000_midi_output_open, |
248 | .close = bcd2000_midi_output_close, |
249 | .trigger = bcd2000_midi_output_trigger, |
250 | }; |
251 | |
252 | static const struct snd_rawmidi_ops bcd2000_midi_input = { |
253 | .open = bcd2000_midi_input_open, |
254 | .close = bcd2000_midi_input_close, |
255 | .trigger = bcd2000_midi_input_trigger, |
256 | }; |
257 | |
258 | static void bcd2000_init_device(struct bcd2000 *bcd2k) |
259 | { |
260 | int ret; |
261 | |
262 | init_usb_anchor(anchor: &bcd2k->anchor); |
263 | usb_anchor_urb(urb: bcd2k->midi_out_urb, anchor: &bcd2k->anchor); |
264 | usb_anchor_urb(urb: bcd2k->midi_in_urb, anchor: &bcd2k->anchor); |
265 | |
266 | /* copy init sequence into buffer */ |
267 | memcpy(bcd2k->midi_out_buf, bcd2000_init_sequence, 52); |
268 | bcd2k->midi_out_urb->transfer_buffer_length = 52; |
269 | |
270 | /* submit sequence */ |
271 | ret = usb_submit_urb(urb: bcd2k->midi_out_urb, GFP_KERNEL); |
272 | if (ret < 0) |
273 | dev_err(&bcd2k->dev->dev, PREFIX |
274 | "%s: usb_submit_urb() out failed, ret=%d: " , |
275 | __func__, ret); |
276 | else |
277 | bcd2k->midi_out_active = 1; |
278 | |
279 | /* pass URB to device to enable button and controller events */ |
280 | ret = usb_submit_urb(urb: bcd2k->midi_in_urb, GFP_KERNEL); |
281 | if (ret < 0) |
282 | dev_err(&bcd2k->dev->dev, PREFIX |
283 | "%s: usb_submit_urb() in failed, ret=%d: " , |
284 | __func__, ret); |
285 | |
286 | /* ensure initialization is finished */ |
287 | usb_wait_anchor_empty_timeout(anchor: &bcd2k->anchor, timeout: 1000); |
288 | } |
289 | |
290 | static int bcd2000_init_midi(struct bcd2000 *bcd2k) |
291 | { |
292 | int ret; |
293 | struct snd_rawmidi *rmidi; |
294 | |
295 | ret = snd_rawmidi_new(card: bcd2k->card, id: bcd2k->card->shortname, device: 0, |
296 | output_count: 1, /* output */ |
297 | input_count: 1, /* input */ |
298 | rmidi: &rmidi); |
299 | |
300 | if (ret < 0) |
301 | return ret; |
302 | |
303 | strscpy(rmidi->name, bcd2k->card->shortname, sizeof(rmidi->name)); |
304 | |
305 | rmidi->info_flags = SNDRV_RAWMIDI_INFO_DUPLEX; |
306 | rmidi->private_data = bcd2k; |
307 | |
308 | rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT; |
309 | snd_rawmidi_set_ops(rmidi, stream: SNDRV_RAWMIDI_STREAM_OUTPUT, |
310 | ops: &bcd2000_midi_output); |
311 | |
312 | rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT; |
313 | snd_rawmidi_set_ops(rmidi, stream: SNDRV_RAWMIDI_STREAM_INPUT, |
314 | ops: &bcd2000_midi_input); |
315 | |
316 | bcd2k->rmidi = rmidi; |
317 | |
318 | bcd2k->midi_in_urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL); |
319 | bcd2k->midi_out_urb = usb_alloc_urb(iso_packets: 0, GFP_KERNEL); |
320 | |
321 | if (!bcd2k->midi_in_urb || !bcd2k->midi_out_urb) { |
322 | dev_err(&bcd2k->dev->dev, PREFIX "usb_alloc_urb failed\n" ); |
323 | return -ENOMEM; |
324 | } |
325 | |
326 | usb_fill_int_urb(urb: bcd2k->midi_in_urb, dev: bcd2k->dev, |
327 | usb_rcvintpipe(bcd2k->dev, 0x81), |
328 | transfer_buffer: bcd2k->midi_in_buf, BUFSIZE, |
329 | complete_fn: bcd2000_input_complete, context: bcd2k, interval: 1); |
330 | |
331 | usb_fill_int_urb(urb: bcd2k->midi_out_urb, dev: bcd2k->dev, |
332 | usb_sndintpipe(bcd2k->dev, 0x1), |
333 | transfer_buffer: bcd2k->midi_out_buf, BUFSIZE, |
334 | complete_fn: bcd2000_output_complete, context: bcd2k, interval: 1); |
335 | |
336 | /* sanity checks of EPs before actually submitting */ |
337 | if (usb_urb_ep_type_check(urb: bcd2k->midi_in_urb) || |
338 | usb_urb_ep_type_check(urb: bcd2k->midi_out_urb)) { |
339 | dev_err(&bcd2k->dev->dev, "invalid MIDI EP\n" ); |
340 | return -EINVAL; |
341 | } |
342 | |
343 | bcd2000_init_device(bcd2k); |
344 | |
345 | return 0; |
346 | } |
347 | |
348 | static void bcd2000_free_usb_related_resources(struct bcd2000 *bcd2k, |
349 | struct usb_interface *interface) |
350 | { |
351 | usb_kill_urb(urb: bcd2k->midi_out_urb); |
352 | usb_kill_urb(urb: bcd2k->midi_in_urb); |
353 | |
354 | usb_free_urb(urb: bcd2k->midi_out_urb); |
355 | usb_free_urb(urb: bcd2k->midi_in_urb); |
356 | |
357 | if (bcd2k->intf) { |
358 | usb_set_intfdata(intf: bcd2k->intf, NULL); |
359 | bcd2k->intf = NULL; |
360 | } |
361 | } |
362 | |
363 | static int bcd2000_probe(struct usb_interface *interface, |
364 | const struct usb_device_id *usb_id) |
365 | { |
366 | struct snd_card *card; |
367 | struct bcd2000 *bcd2k; |
368 | unsigned int card_index; |
369 | char usb_path[32]; |
370 | int err; |
371 | |
372 | mutex_lock(&devices_mutex); |
373 | |
374 | for (card_index = 0; card_index < SNDRV_CARDS; ++card_index) |
375 | if (!test_bit(card_index, devices_used)) |
376 | break; |
377 | |
378 | if (card_index >= SNDRV_CARDS) { |
379 | mutex_unlock(lock: &devices_mutex); |
380 | return -ENOENT; |
381 | } |
382 | |
383 | err = snd_card_new(parent: &interface->dev, idx: index[card_index], xid: id[card_index], |
384 | THIS_MODULE, extra_size: sizeof(*bcd2k), card_ret: &card); |
385 | if (err < 0) { |
386 | mutex_unlock(lock: &devices_mutex); |
387 | return err; |
388 | } |
389 | |
390 | bcd2k = card->private_data; |
391 | bcd2k->dev = interface_to_usbdev(interface); |
392 | bcd2k->card = card; |
393 | bcd2k->card_index = card_index; |
394 | bcd2k->intf = interface; |
395 | |
396 | snd_card_set_dev(card, &interface->dev); |
397 | |
398 | strscpy(card->driver, "snd-bcd2000" , sizeof(card->driver)); |
399 | strscpy(card->shortname, "BCD2000" , sizeof(card->shortname)); |
400 | usb_make_path(dev: bcd2k->dev, buf: usb_path, size: sizeof(usb_path)); |
401 | snprintf(buf: bcd2k->card->longname, size: sizeof(bcd2k->card->longname), |
402 | fmt: "Behringer BCD2000 at %s" , |
403 | usb_path); |
404 | |
405 | err = bcd2000_init_midi(bcd2k); |
406 | if (err < 0) |
407 | goto probe_error; |
408 | |
409 | err = snd_card_register(card); |
410 | if (err < 0) |
411 | goto probe_error; |
412 | |
413 | usb_set_intfdata(intf: interface, data: bcd2k); |
414 | set_bit(nr: card_index, addr: devices_used); |
415 | |
416 | mutex_unlock(lock: &devices_mutex); |
417 | return 0; |
418 | |
419 | probe_error: |
420 | dev_info(&bcd2k->dev->dev, PREFIX "error during probing" ); |
421 | bcd2000_free_usb_related_resources(bcd2k, interface); |
422 | snd_card_free(card); |
423 | mutex_unlock(lock: &devices_mutex); |
424 | return err; |
425 | } |
426 | |
427 | static void bcd2000_disconnect(struct usb_interface *interface) |
428 | { |
429 | struct bcd2000 *bcd2k = usb_get_intfdata(intf: interface); |
430 | |
431 | if (!bcd2k) |
432 | return; |
433 | |
434 | mutex_lock(&devices_mutex); |
435 | |
436 | /* make sure that userspace cannot create new requests */ |
437 | snd_card_disconnect(card: bcd2k->card); |
438 | |
439 | bcd2000_free_usb_related_resources(bcd2k, interface); |
440 | |
441 | clear_bit(nr: bcd2k->card_index, addr: devices_used); |
442 | |
443 | snd_card_free_when_closed(card: bcd2k->card); |
444 | |
445 | mutex_unlock(lock: &devices_mutex); |
446 | } |
447 | |
448 | static struct usb_driver bcd2000_driver = { |
449 | .name = "snd-bcd2000" , |
450 | .probe = bcd2000_probe, |
451 | .disconnect = bcd2000_disconnect, |
452 | .id_table = id_table, |
453 | }; |
454 | |
455 | module_usb_driver(bcd2000_driver); |
456 | |
457 | MODULE_DEVICE_TABLE(usb, id_table); |
458 | MODULE_AUTHOR("Mario Kicherer, dev@kicherer.org" ); |
459 | MODULE_DESCRIPTION("Behringer BCD2000 driver" ); |
460 | MODULE_LICENSE("GPL" ); |
461 | |