1 /* 2 * Behringer BCD2000 driver 3 * 4 * Copyright (C) 2014 Mario Kicherer (dev@kicherer.org) 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 */ 16 17 #include <linux/kernel.h> 18 #include <linux/errno.h> 19 #include <linux/init.h> 20 #include <linux/slab.h> 21 #include <linux/module.h> 22 #include <linux/bitmap.h> 23 #include <linux/usb.h> 24 #include <linux/usb/audio.h> 25 #include <sound/core.h> 26 #include <sound/initval.h> 27 #include <sound/rawmidi.h> 28 29 #define PREFIX "snd-bcd2000: " 30 #define BUFSIZE 64 31 32 static struct usb_device_id id_table[] = { 33 { USB_DEVICE(0x1397, 0x00bd) }, 34 { }, 35 }; 36 37 static unsigned char device_cmd_prefix[] = {0x03, 0x00}; 38 39 static unsigned char bcd2000_init_sequence[] = { 40 0x07, 0x00, 0x00, 0x00, 0x78, 0x48, 0x1c, 0x81, 41 0xc4, 0x00, 0x00, 0x00, 0x5e, 0x53, 0x4a, 0xf7, 42 0x18, 0xfa, 0x11, 0xff, 0x6c, 0xf3, 0x90, 0xff, 43 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 44 0x18, 0xfa, 0x11, 0xff, 0x14, 0x00, 0x00, 0x00, 45 0x00, 0x00, 0x00, 0x00, 0xf2, 0x34, 0x4a, 0xf7, 46 0x18, 0xfa, 0x11, 0xff 47 }; 48 49 struct bcd2000 { 50 struct usb_device *dev; 51 struct snd_card *card; 52 struct usb_interface *intf; 53 int card_index; 54 55 int midi_out_active; 56 struct snd_rawmidi *rmidi; 57 struct snd_rawmidi_substream *midi_receive_substream; 58 struct snd_rawmidi_substream *midi_out_substream; 59 60 unsigned char midi_in_buf[BUFSIZE]; 61 unsigned char midi_out_buf[BUFSIZE]; 62 63 struct urb *midi_out_urb; 64 struct urb *midi_in_urb; 65 66 struct usb_anchor anchor; 67 }; 68 69 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; 70 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; 71 72 static DEFINE_MUTEX(devices_mutex); 73 static DECLARE_BITMAP(devices_used, SNDRV_CARDS); 74 static struct usb_driver bcd2000_driver; 75 76 #ifdef CONFIG_SND_DEBUG 77 static void bcd2000_dump_buffer(const char *prefix, const char *buf, int len) 78 { 79 print_hex_dump(KERN_DEBUG, prefix, 80 DUMP_PREFIX_NONE, 16, 1, 81 buf, len, false); 82 } 83 #else 84 static void bcd2000_dump_buffer(const char *prefix, const char *buf, int len) {} 85 #endif 86 87 static int bcd2000_midi_input_open(struct snd_rawmidi_substream *substream) 88 { 89 return 0; 90 } 91 92 static int bcd2000_midi_input_close(struct snd_rawmidi_substream *substream) 93 { 94 return 0; 95 } 96 97 /* (de)register midi substream from client */ 98 static void bcd2000_midi_input_trigger(struct snd_rawmidi_substream *substream, 99 int up) 100 { 101 struct bcd2000 *bcd2k = substream->rmidi->private_data; 102 bcd2k->midi_receive_substream = up ? substream : NULL; 103 } 104 105 static void bcd2000_midi_handle_input(struct bcd2000 *bcd2k, 106 const unsigned char *buf, unsigned int buf_len) 107 { 108 unsigned int payload_length, tocopy; 109 struct snd_rawmidi_substream *midi_receive_substream; 110 111 midi_receive_substream = ACCESS_ONCE(bcd2k->midi_receive_substream); 112 if (!midi_receive_substream) 113 return; 114 115 bcd2000_dump_buffer(PREFIX "received from device: ", buf, buf_len); 116 117 if (buf_len < 2) 118 return; 119 120 payload_length = buf[0]; 121 122 /* ignore packets without payload */ 123 if (payload_length == 0) 124 return; 125 126 tocopy = min(payload_length, buf_len-1); 127 128 bcd2000_dump_buffer(PREFIX "sending to userspace: ", 129 &buf[1], tocopy); 130 131 snd_rawmidi_receive(midi_receive_substream, 132 &buf[1], tocopy); 133 } 134 135 static void bcd2000_midi_send(struct bcd2000 *bcd2k) 136 { 137 int len, ret; 138 struct snd_rawmidi_substream *midi_out_substream; 139 140 BUILD_BUG_ON(sizeof(device_cmd_prefix) >= BUFSIZE); 141 142 midi_out_substream = ACCESS_ONCE(bcd2k->midi_out_substream); 143 if (!midi_out_substream) 144 return; 145 146 /* copy command prefix bytes */ 147 memcpy(bcd2k->midi_out_buf, device_cmd_prefix, 148 sizeof(device_cmd_prefix)); 149 150 /* 151 * get MIDI packet and leave space for command prefix 152 * and payload length 153 */ 154 len = snd_rawmidi_transmit(midi_out_substream, 155 bcd2k->midi_out_buf + 3, BUFSIZE - 3); 156 157 if (len < 0) 158 dev_err(&bcd2k->dev->dev, "%s: snd_rawmidi_transmit error %d\n", 159 __func__, len); 160 161 if (len <= 0) 162 return; 163 164 /* set payload length */ 165 bcd2k->midi_out_buf[2] = len; 166 bcd2k->midi_out_urb->transfer_buffer_length = BUFSIZE; 167 168 bcd2000_dump_buffer(PREFIX "sending to device: ", 169 bcd2k->midi_out_buf, len+3); 170 171 /* send packet to the BCD2000 */ 172 ret = usb_submit_urb(bcd2k->midi_out_urb, GFP_ATOMIC); 173 if (ret < 0) 174 dev_err(&bcd2k->dev->dev, PREFIX 175 "%s (%p): usb_submit_urb() failed, ret=%d, len=%d\n", 176 __func__, midi_out_substream, ret, len); 177 else 178 bcd2k->midi_out_active = 1; 179 } 180 181 static int bcd2000_midi_output_open(struct snd_rawmidi_substream *substream) 182 { 183 return 0; 184 } 185 186 static int bcd2000_midi_output_close(struct snd_rawmidi_substream *substream) 187 { 188 struct bcd2000 *bcd2k = substream->rmidi->private_data; 189 190 if (bcd2k->midi_out_active) { 191 usb_kill_urb(bcd2k->midi_out_urb); 192 bcd2k->midi_out_active = 0; 193 } 194 195 return 0; 196 } 197 198 /* (de)register midi substream from client */ 199 static void bcd2000_midi_output_trigger(struct snd_rawmidi_substream *substream, 200 int up) 201 { 202 struct bcd2000 *bcd2k = substream->rmidi->private_data; 203 204 if (up) { 205 bcd2k->midi_out_substream = substream; 206 /* check if there is data userspace wants to send */ 207 if (!bcd2k->midi_out_active) 208 bcd2000_midi_send(bcd2k); 209 } else { 210 bcd2k->midi_out_substream = NULL; 211 } 212 } 213 214 static void bcd2000_output_complete(struct urb *urb) 215 { 216 struct bcd2000 *bcd2k = urb->context; 217 218 bcd2k->midi_out_active = 0; 219 220 if (urb->status) 221 dev_warn(&urb->dev->dev, 222 PREFIX "output urb->status: %d\n", urb->status); 223 224 if (urb->status == -ESHUTDOWN) 225 return; 226 227 /* check if there is more data userspace wants to send */ 228 bcd2000_midi_send(bcd2k); 229 } 230 231 static void bcd2000_input_complete(struct urb *urb) 232 { 233 int ret; 234 struct bcd2000 *bcd2k = urb->context; 235 236 if (urb->status) 237 dev_warn(&urb->dev->dev, 238 PREFIX "input urb->status: %i\n", urb->status); 239 240 if (!bcd2k || urb->status == -ESHUTDOWN) 241 return; 242 243 if (urb->actual_length > 0) 244 bcd2000_midi_handle_input(bcd2k, urb->transfer_buffer, 245 urb->actual_length); 246 247 /* return URB to device */ 248 ret = usb_submit_urb(bcd2k->midi_in_urb, GFP_ATOMIC); 249 if (ret < 0) 250 dev_err(&bcd2k->dev->dev, PREFIX 251 "%s: usb_submit_urb() failed, ret=%d\n", 252 __func__, ret); 253 } 254 255 static struct snd_rawmidi_ops bcd2000_midi_output = { 256 .open = bcd2000_midi_output_open, 257 .close = bcd2000_midi_output_close, 258 .trigger = bcd2000_midi_output_trigger, 259 }; 260 261 static struct snd_rawmidi_ops bcd2000_midi_input = { 262 .open = bcd2000_midi_input_open, 263 .close = bcd2000_midi_input_close, 264 .trigger = bcd2000_midi_input_trigger, 265 }; 266 267 static void bcd2000_init_device(struct bcd2000 *bcd2k) 268 { 269 int ret; 270 271 init_usb_anchor(&bcd2k->anchor); 272 usb_anchor_urb(bcd2k->midi_out_urb, &bcd2k->anchor); 273 usb_anchor_urb(bcd2k->midi_in_urb, &bcd2k->anchor); 274 275 /* copy init sequence into buffer */ 276 memcpy(bcd2k->midi_out_buf, bcd2000_init_sequence, 52); 277 bcd2k->midi_out_urb->transfer_buffer_length = 52; 278 279 /* submit sequence */ 280 ret = usb_submit_urb(bcd2k->midi_out_urb, GFP_KERNEL); 281 if (ret < 0) 282 dev_err(&bcd2k->dev->dev, PREFIX 283 "%s: usb_submit_urb() out failed, ret=%d: ", 284 __func__, ret); 285 else 286 bcd2k->midi_out_active = 1; 287 288 /* pass URB to device to enable button and controller events */ 289 ret = usb_submit_urb(bcd2k->midi_in_urb, GFP_KERNEL); 290 if (ret < 0) 291 dev_err(&bcd2k->dev->dev, PREFIX 292 "%s: usb_submit_urb() in failed, ret=%d: ", 293 __func__, ret); 294 295 /* ensure initialization is finished */ 296 usb_wait_anchor_empty_timeout(&bcd2k->anchor, 1000); 297 } 298 299 static int bcd2000_init_midi(struct bcd2000 *bcd2k) 300 { 301 int ret; 302 struct snd_rawmidi *rmidi; 303 304 ret = snd_rawmidi_new(bcd2k->card, bcd2k->card->shortname, 0, 305 1, /* output */ 306 1, /* input */ 307 &rmidi); 308 309 if (ret < 0) 310 return ret; 311 312 strlcpy(rmidi->name, bcd2k->card->shortname, sizeof(rmidi->name)); 313 314 rmidi->info_flags = SNDRV_RAWMIDI_INFO_DUPLEX; 315 rmidi->private_data = bcd2k; 316 317 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_OUTPUT; 318 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_OUTPUT, 319 &bcd2000_midi_output); 320 321 rmidi->info_flags |= SNDRV_RAWMIDI_INFO_INPUT; 322 snd_rawmidi_set_ops(rmidi, SNDRV_RAWMIDI_STREAM_INPUT, 323 &bcd2000_midi_input); 324 325 bcd2k->rmidi = rmidi; 326 327 bcd2k->midi_in_urb = usb_alloc_urb(0, GFP_KERNEL); 328 bcd2k->midi_out_urb = usb_alloc_urb(0, GFP_KERNEL); 329 330 if (!bcd2k->midi_in_urb || !bcd2k->midi_out_urb) { 331 dev_err(&bcd2k->dev->dev, PREFIX "usb_alloc_urb failed\n"); 332 return -ENOMEM; 333 } 334 335 usb_fill_int_urb(bcd2k->midi_in_urb, bcd2k->dev, 336 usb_rcvintpipe(bcd2k->dev, 0x81), 337 bcd2k->midi_in_buf, BUFSIZE, 338 bcd2000_input_complete, bcd2k, 1); 339 340 usb_fill_int_urb(bcd2k->midi_out_urb, bcd2k->dev, 341 usb_sndintpipe(bcd2k->dev, 0x1), 342 bcd2k->midi_out_buf, BUFSIZE, 343 bcd2000_output_complete, bcd2k, 1); 344 345 bcd2000_init_device(bcd2k); 346 347 return 0; 348 } 349 350 static void bcd2000_free_usb_related_resources(struct bcd2000 *bcd2k, 351 struct usb_interface *interface) 352 { 353 /* usb_kill_urb not necessary, urb is aborted automatically */ 354 355 usb_free_urb(bcd2k->midi_out_urb); 356 usb_free_urb(bcd2k->midi_in_urb); 357 358 if (bcd2k->intf) { 359 usb_set_intfdata(bcd2k->intf, NULL); 360 bcd2k->intf = NULL; 361 } 362 } 363 364 static int bcd2000_probe(struct usb_interface *interface, 365 const struct usb_device_id *usb_id) 366 { 367 struct snd_card *card; 368 struct bcd2000 *bcd2k; 369 unsigned int card_index; 370 char usb_path[32]; 371 int err; 372 373 mutex_lock(&devices_mutex); 374 375 for (card_index = 0; card_index < SNDRV_CARDS; ++card_index) 376 if (!test_bit(card_index, devices_used)) 377 break; 378 379 if (card_index >= SNDRV_CARDS) { 380 mutex_unlock(&devices_mutex); 381 return -ENOENT; 382 } 383 384 err = snd_card_new(&interface->dev, index[card_index], id[card_index], 385 THIS_MODULE, sizeof(*bcd2k), &card); 386 if (err < 0) { 387 mutex_unlock(&devices_mutex); 388 return err; 389 } 390 391 bcd2k = card->private_data; 392 bcd2k->dev = interface_to_usbdev(interface); 393 bcd2k->card = card; 394 bcd2k->card_index = card_index; 395 bcd2k->intf = interface; 396 397 snd_card_set_dev(card, &interface->dev); 398 399 strncpy(card->driver, "snd-bcd2000", sizeof(card->driver)); 400 strncpy(card->shortname, "BCD2000", sizeof(card->shortname)); 401 usb_make_path(bcd2k->dev, usb_path, sizeof(usb_path)); 402 snprintf(bcd2k->card->longname, sizeof(bcd2k->card->longname), 403 "Behringer BCD2000 at %s", 404 usb_path); 405 406 err = bcd2000_init_midi(bcd2k); 407 if (err < 0) 408 goto probe_error; 409 410 err = snd_card_register(card); 411 if (err < 0) 412 goto probe_error; 413 414 usb_set_intfdata(interface, bcd2k); 415 set_bit(card_index, devices_used); 416 417 mutex_unlock(&devices_mutex); 418 return 0; 419 420 probe_error: 421 dev_info(&bcd2k->dev->dev, PREFIX "error during probing"); 422 bcd2000_free_usb_related_resources(bcd2k, interface); 423 snd_card_free(card); 424 mutex_unlock(&devices_mutex); 425 return err; 426 } 427 428 static void bcd2000_disconnect(struct usb_interface *interface) 429 { 430 struct bcd2000 *bcd2k = usb_get_intfdata(interface); 431 432 if (!bcd2k) 433 return; 434 435 mutex_lock(&devices_mutex); 436 437 /* make sure that userspace cannot create new requests */ 438 snd_card_disconnect(bcd2k->card); 439 440 bcd2000_free_usb_related_resources(bcd2k, interface); 441 442 clear_bit(bcd2k->card_index, devices_used); 443 444 snd_card_free_when_closed(bcd2k->card); 445 446 mutex_unlock(&devices_mutex); 447 } 448 449 static struct usb_driver bcd2000_driver = { 450 .name = "snd-bcd2000", 451 .probe = bcd2000_probe, 452 .disconnect = bcd2000_disconnect, 453 .id_table = id_table, 454 }; 455 456 module_usb_driver(bcd2000_driver); 457 458 MODULE_DEVICE_TABLE(usb, id_table); 459 MODULE_AUTHOR("Mario Kicherer, dev@kicherer.org"); 460 MODULE_DESCRIPTION("Behringer BCD2000 driver"); 461 MODULE_LICENSE("GPL"); 462