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, 71 DUMP_PREFIX_NONE, 16, 1, 72 buf, len, 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, 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[1], tocopy); 121 122 snd_rawmidi_receive(midi_receive_substream, 123 &buf[1], 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(midi_out_substream, 146 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 bcd2k->midi_out_buf, len+3); 161 162 /* send packet to the BCD2000 */ 163 ret = usb_submit_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(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, urb->transfer_buffer, 236 urb->actual_length); 237 238 /* return URB to device */ 239 ret = usb_submit_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(&bcd2k->anchor); 263 usb_anchor_urb(bcd2k->midi_out_urb, &bcd2k->anchor); 264 usb_anchor_urb(bcd2k->midi_in_urb, &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(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(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(&bcd2k->anchor, 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(bcd2k->card, bcd2k->card->shortname, 0, 296 1, /* output */ 297 1, /* input */ 298 &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, SNDRV_RAWMIDI_STREAM_OUTPUT, 310 &bcd2000_midi_output); 311 312 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT; 313 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, 314 &bcd2000_midi_input); 315 316 bcd2k->rmidi = rmidi; 317 318 bcd2k->midi_in_urb = usb_alloc_urb(0, GFP_KERNEL); 319 bcd2k->midi_out_urb = usb_alloc_urb(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(bcd2k->midi_in_urb, bcd2k->dev, 327 usb_rcvintpipe(bcd2k->dev, 0x81), 328 bcd2k->midi_in_buf, BUFSIZE, 329 bcd2000_input_complete, bcd2k, 1); 330 331 usb_fill_int_urb(bcd2k->midi_out_urb, bcd2k->dev, 332 usb_sndintpipe(bcd2k->dev, 0x1), 333 bcd2k->midi_out_buf, BUFSIZE, 334 bcd2000_output_complete, bcd2k, 1); 335 336 /* sanity checks of EPs before actually submitting */ 337 if (usb_urb_ep_type_check(bcd2k->midi_in_urb) || 338 usb_urb_ep_type_check(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(bcd2k->midi_out_urb); 352 usb_kill_urb(bcd2k->midi_in_urb); 353 354 usb_free_urb(bcd2k->midi_out_urb); 355 usb_free_urb(bcd2k->midi_in_urb); 356 357 if (bcd2k->intf) { 358 usb_set_intfdata(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(&devices_mutex); 380 return -ENOENT; 381 } 382 383 err = snd_card_new(&interface->dev, index[card_index], id[card_index], 384 THIS_MODULE, sizeof(*bcd2k), &card); 385 if (err < 0) { 386 mutex_unlock(&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 strncpy(card->driver, "snd-bcd2000", sizeof(card->driver)); 399 strncpy(card->shortname, "BCD2000", sizeof(card->shortname)); 400 usb_make_path(bcd2k->dev, usb_path, sizeof(usb_path)); 401 snprintf(bcd2k->card->longname, sizeof(bcd2k->card->longname), 402 "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(interface, bcd2k); 414 set_bit(card_index, devices_used); 415 416 mutex_unlock(&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(&devices_mutex); 424 return err; 425 } 426 427 static void bcd2000_disconnect(struct usb_interface *interface) 428 { 429 struct bcd2000 *bcd2k = usb_get_intfdata(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(bcd2k->card); 438 439 bcd2000_free_usb_related_resources(bcd2k, interface); 440 441 clear_bit(bcd2k->card_index, devices_used); 442 443 snd_card_free_when_closed(bcd2k->card); 444 445 mutex_unlock(&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