sound/usb/line6/driver.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Line 6 Linux USB driver
   4  *
   5  * Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/export.h>
  11 #include <linux/slab.h>
  12 #include <linux/usb.h>
  13
  14 #include <sound/core.h>
  15 #include <sound/initval.h>
  16 #include <sound/hwdep.h>
  17
  18 #include "capture.h"
  19 #include "driver.h"
  20 #include "midi.h"
  21 #include "playback.h"
  22
  23 #define DRIVER_AUTHOR  "Markus Grabner <grabner@icg.tugraz.at>"
  24 #define DRIVER_DESC    "Line 6 USB Driver"
  25
  26 /*
  27         This is Line 6's MIDI manufacturer ID.
  28 */
  29 const unsigned char line6_midi_id[3] = {
  30         0x00, 0x01, 0x0c
  31 };
  32 EXPORT_SYMBOL_GPL(line6_midi_id);
  33
  34 /*
  35         Code to request version of POD, Variax interface
  36         (and maybe other devices).
  37 */
  38 static const char line6_request_version[] = {
  39         0xf0, 0x7e, 0x7f, 0x06, 0x01, 0xf7
  40 };
  41
  42 /*
  43          Class for asynchronous messages.
  44 */
  45 struct message {
  46         struct usb_line6 *line6;
  47         const char *buffer;
  48         int size;
  49         int done;
  50 };
  51
  52 /*
  53         Forward declarations.
  54 */
  55 static void line6_data_received(struct urb *urb);
  56 static int line6_send_raw_message_async_part(struct message *msg,
  57                                              struct urb *urb);
  58
  59 /*
  60         Start to listen on endpoint.
  61 */
  62 static int line6_start_listen(struct usb_line6 *line6)
  63 {
  64         int err;
  65
  66         if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
  67                 usb_fill_int_urb(line6->urb_listen, line6->usbdev,
  68                         usb_rcvintpipe(line6->usbdev, line6->properties->ep_ctrl_r),
  69                         line6->buffer_listen, LINE6_BUFSIZE_LISTEN,
  70                         line6_data_received, line6, line6->interval);
  71         } else {
  72                 usb_fill_bulk_urb(line6->urb_listen, line6->usbdev,
  73                         usb_rcvbulkpipe(line6->usbdev, line6->properties->ep_ctrl_r),
  74                         line6->buffer_listen, LINE6_BUFSIZE_LISTEN,
  75                         line6_data_received, line6);
  76         }
  77
  78         /* sanity checks of EP before actually submitting */
  79         if (usb_urb_ep_type_check(line6->urb_listen)) {
  80                 dev_err(line6->ifcdev, "invalid control EP\n");
  81                 return -EINVAL;
  82         }
  83
  84         line6->urb_listen->actual_length = 0;
  85         err = usb_submit_urb(line6->urb_listen, GFP_ATOMIC);
  86         return err;
  87 }
  88
  89 /*
  90         Stop listening on endpoint.
  91 */
  92 static void line6_stop_listen(struct usb_line6 *line6)
  93 {
  94         usb_kill_urb(line6->urb_listen);
  95 }
  96
  97 /*
  98         Send raw message in pieces of wMaxPacketSize bytes.
  99 */
 100 static int line6_send_raw_message(struct usb_line6 *line6, const char *buffer,
 101                                   int size)
 102 {
 103         int i, done = 0;
 104         const struct line6_properties *properties = line6->properties;
 105
 106         for (i = 0; i < size; i += line6->max_packet_size) {
 107                 int partial;
 108                 const char *frag_buf = buffer + i;
 109                 int frag_size = min(line6->max_packet_size, size - i);
 110                 int retval;
 111
 112                 if (properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 113                         retval = usb_interrupt_msg(line6->usbdev,
 114                                                 usb_sndintpipe(line6->usbdev, properties->ep_ctrl_w),
 115                                                 (char *)frag_buf, frag_size,
 116                                                 &partial, LINE6_TIMEOUT * HZ);
 117                 } else {
 118                         retval = usb_bulk_msg(line6->usbdev,
 119                                                 usb_sndbulkpipe(line6->usbdev, properties->ep_ctrl_w),
 120                                                 (char *)frag_buf, frag_size,
 121                                                 &partial, LINE6_TIMEOUT * HZ);
 122                 }
 123
 124                 if (retval) {
 125                         dev_err(line6->ifcdev,
 126                                 "usb_bulk_msg failed (%d)\n", retval);
 127                         break;
 128                 }
 129
 130                 done += frag_size;
 131         }
 132
 133         return done;
 134 }
 135
 136 /*
 137         Notification of completion of asynchronous request transmission.
 138 */
 139 static void line6_async_request_sent(struct urb *urb)
 140 {
 141         struct message *msg = (struct message *)urb->context;
 142
 143         if (msg->done >= msg->size) {
 144                 usb_free_urb(urb);
 145                 kfree(msg);
 146         } else
 147                 line6_send_raw_message_async_part(msg, urb);
 148 }
 149
 150 /*
 151         Asynchronously send part of a raw message.
 152 */
 153 static int line6_send_raw_message_async_part(struct message *msg,
 154                                              struct urb *urb)
 155 {
 156         int retval;
 157         struct usb_line6 *line6 = msg->line6;
 158         int done = msg->done;
 159         int bytes = min(msg->size - done, line6->max_packet_size);
 160
 161         if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 162                 usb_fill_int_urb(urb, line6->usbdev,
 163                         usb_sndintpipe(line6->usbdev, line6->properties->ep_ctrl_w),
 164                         (char *)msg->buffer + done, bytes,
 165                         line6_async_request_sent, msg, line6->interval);
 166         } else {
 167                 usb_fill_bulk_urb(urb, line6->usbdev,
 168                         usb_sndbulkpipe(line6->usbdev, line6->properties->ep_ctrl_w),
 169                         (char *)msg->buffer + done, bytes,
 170                         line6_async_request_sent, msg);
 171         }
 172
 173         msg->done += bytes;
 174
 175         /* sanity checks of EP before actually submitting */
 176         retval = usb_urb_ep_type_check(urb);
 177         if (retval < 0)
 178                 goto error;
 179
 180         retval = usb_submit_urb(urb, GFP_ATOMIC);
 181         if (retval < 0)
 182                 goto error;
 183
 184         return 0;
 185
 186  error:
 187         dev_err(line6->ifcdev, "%s: usb_submit_urb failed (%d)\n",
 188                 __func__, retval);
 189         usb_free_urb(urb);
 190         kfree(msg);
 191         return retval;
 192 }
 193
 194 /*
 195         Asynchronously send raw message.
 196 */
 197 int line6_send_raw_message_async(struct usb_line6 *line6, const char *buffer,
 198                                  int size)
 199 {
 200         struct message *msg;
 201         struct urb *urb;
 202
 203         /* create message: */
 204         msg = kmalloc(sizeof(struct message), GFP_ATOMIC);
 205         if (msg == NULL)
 206                 return -ENOMEM;
 207
 208         /* create URB: */
 209         urb = usb_alloc_urb(0, GFP_ATOMIC);
 210
 211         if (urb == NULL) {
 212                 kfree(msg);
 213                 return -ENOMEM;
 214         }
 215
 216         /* set message data: */
 217         msg->line6 = line6;
 218         msg->buffer = buffer;
 219         msg->size = size;
 220         msg->done = 0;
 221
 222         /* start sending: */
 223         return line6_send_raw_message_async_part(msg, urb);
 224 }
 225 EXPORT_SYMBOL_GPL(line6_send_raw_message_async);
 226
 227 /*
 228         Send asynchronous device version request.
 229 */
 230 int line6_version_request_async(struct usb_line6 *line6)
 231 {
 232         char *buffer;
 233         int retval;
 234
 235         buffer = kmemdup(line6_request_version,
 236                         sizeof(line6_request_version), GFP_ATOMIC);
 237         if (buffer == NULL)
 238                 return -ENOMEM;
 239
 240         retval = line6_send_raw_message_async(line6, buffer,
 241                                               sizeof(line6_request_version));
 242         kfree(buffer);
 243         return retval;
 244 }
 245 EXPORT_SYMBOL_GPL(line6_version_request_async);
 246
 247 /*
 248         Send sysex message in pieces of wMaxPacketSize bytes.
 249 */
 250 int line6_send_sysex_message(struct usb_line6 *line6, const char *buffer,
 251                              int size)
 252 {
 253         return line6_send_raw_message(line6, buffer,
 254                                       size + SYSEX_EXTRA_SIZE) -
 255             SYSEX_EXTRA_SIZE;
 256 }
 257 EXPORT_SYMBOL_GPL(line6_send_sysex_message);
 258
 259 /*
 260         Allocate buffer for sysex message and prepare header.
 261         @param code sysex message code
 262         @param size number of bytes between code and sysex end
 263 */
 264 char *line6_alloc_sysex_buffer(struct usb_line6 *line6, int code1, int code2,
 265                                int size)
 266 {
 267         char *buffer = kmalloc(size + SYSEX_EXTRA_SIZE, GFP_ATOMIC);
 268
 269         if (!buffer)
 270                 return NULL;
 271
 272         buffer[0] = LINE6_SYSEX_BEGIN;
 273         memcpy(buffer + 1, line6_midi_id, sizeof(line6_midi_id));
 274         buffer[sizeof(line6_midi_id) + 1] = code1;
 275         buffer[sizeof(line6_midi_id) + 2] = code2;
 276         buffer[sizeof(line6_midi_id) + 3 + size] = LINE6_SYSEX_END;
 277         return buffer;
 278 }
 279 EXPORT_SYMBOL_GPL(line6_alloc_sysex_buffer);
 280
 281 /*
 282         Notification of data received from the Line 6 device.
 283 */
 284 static void line6_data_received(struct urb *urb)
 285 {
 286         struct usb_line6 *line6 = (struct usb_line6 *)urb->context;
 287         struct midi_buffer *mb = &line6->line6midi->midibuf_in;
 288         int done;
 289
 290         if (urb->status == -ESHUTDOWN)
 291                 return;
 292
 293         if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 294                 done =
 295                         line6_midibuf_write(mb, urb->transfer_buffer, urb->actual_length);
 296
 297                 if (done < urb->actual_length) {
 298                         line6_midibuf_ignore(mb, done);
 299                         dev_dbg(line6->ifcdev, "%d %d buffer overflow - message skipped\n",
 300                                 done, urb->actual_length);
 301                 }
 302
 303                 for (;;) {
 304                         done =
 305                                 line6_midibuf_read(mb, line6->buffer_message,
 306                                                 LINE6_MIDI_MESSAGE_MAXLEN);
 307
 308                         if (done <= 0)
 309                                 break;
 310
 311                         line6->message_length = done;
 312                         line6_midi_receive(line6, line6->buffer_message, done);
 313
 314                         if (line6->process_message)
 315                                 line6->process_message(line6);
 316                 }
 317         } else {
 318                 line6->buffer_message = urb->transfer_buffer;
 319                 line6->message_length = urb->actual_length;
 320                 if (line6->process_message)
 321                         line6->process_message(line6);
 322                 line6->buffer_message = NULL;
 323         }
 324
 325         line6_start_listen(line6);
 326 }
 327
 328 #define LINE6_READ_WRITE_STATUS_DELAY 2  /* milliseconds */
 329 #define LINE6_READ_WRITE_MAX_RETRIES 50
 330
 331 /*
 332         Read data from device.
 333 */
 334 int line6_read_data(struct usb_line6 *line6, unsigned address, void *data,
 335                     unsigned datalen)
 336 {
 337         struct usb_device *usbdev = line6->usbdev;
 338         int ret;
 339         unsigned char *len;
 340         unsigned count;
 341
 342         if (address > 0xffff || datalen > 0xff)
 343                 return -EINVAL;
 344
 345         len = kmalloc(1, GFP_KERNEL);
 346         if (!len)
 347                 return -ENOMEM;
 348
 349         /* query the serial number: */
 350         ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
 351                               USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 352                               (datalen << 8) | 0x21, address,
 353                               NULL, 0, LINE6_TIMEOUT * HZ);
 354
 355         if (ret < 0) {
 356                 dev_err(line6->ifcdev, "read request failed (error %d)\n", ret);
 357                 goto exit;
 358         }
 359
 360         /* Wait for data length. We'll get 0xff until length arrives. */
 361         for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
 362                 mdelay(LINE6_READ_WRITE_STATUS_DELAY);
 363
 364                 ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
 365                                       USB_TYPE_VENDOR | USB_RECIP_DEVICE |
 366                                       USB_DIR_IN,
 367                                       0x0012, 0x0000, len, 1,
 368                                       LINE6_TIMEOUT * HZ);
 369                 if (ret < 0) {
 370                         dev_err(line6->ifcdev,
 371                                 "receive length failed (error %d)\n", ret);
 372                         goto exit;
 373                 }
 374
 375                 if (*len != 0xff)
 376                         break;
 377         }
 378
 379         ret = -EIO;
 380         if (*len == 0xff) {
 381                 dev_err(line6->ifcdev, "read failed after %d retries\n",
 382                         count);
 383                 goto exit;
 384         } else if (*len != datalen) {
 385                 /* should be equal or something went wrong */
 386                 dev_err(line6->ifcdev,
 387                         "length mismatch (expected %d, got %d)\n",
 388                         (int)datalen, (int)*len);
 389                 goto exit;
 390         }
 391
 392         /* receive the result: */
 393         ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
 394                               USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 395                               0x0013, 0x0000, data, datalen,
 396                               LINE6_TIMEOUT * HZ);
 397
 398         if (ret < 0)
 399                 dev_err(line6->ifcdev, "read failed (error %d)\n", ret);
 400
 401 exit:
 402         kfree(len);
 403         return ret;
 404 }
 405 EXPORT_SYMBOL_GPL(line6_read_data);
 406
 407 /*
 408         Write data to device.
 409 */
 410 int line6_write_data(struct usb_line6 *line6, unsigned address, void *data,
 411                      unsigned datalen)
 412 {
 413         struct usb_device *usbdev = line6->usbdev;
 414         int ret;
 415         unsigned char *status;
 416         int count;
 417
 418         if (address > 0xffff || datalen > 0xffff)
 419                 return -EINVAL;
 420
 421         status = kmalloc(1, GFP_KERNEL);
 422         if (!status)
 423                 return -ENOMEM;
 424
 425         ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
 426                               USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 427                               0x0022, address, data, datalen,
 428                               LINE6_TIMEOUT * HZ);
 429
 430         if (ret < 0) {
 431                 dev_err(line6->ifcdev,
 432                         "write request failed (error %d)\n", ret);
 433                 goto exit;
 434         }
 435
 436         for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
 437                 mdelay(LINE6_READ_WRITE_STATUS_DELAY);
 438
 439                 ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
 440                                       0x67,
 441                                       USB_TYPE_VENDOR | USB_RECIP_DEVICE |
 442                                       USB_DIR_IN,
 443                                       0x0012, 0x0000,
 444                                       status, 1, LINE6_TIMEOUT * HZ);
 445
 446                 if (ret < 0) {
 447                         dev_err(line6->ifcdev,
 448                                 "receiving status failed (error %d)\n", ret);
 449                         goto exit;
 450                 }
 451
 452                 if (*status != 0xff)
 453                         break;
 454         }
 455
 456         if (*status == 0xff) {
 457                 dev_err(line6->ifcdev, "write failed after %d retries\n",
 458                         count);
 459                 ret = -EIO;
 460         } else if (*status != 0) {
 461                 dev_err(line6->ifcdev, "write failed (error %d)\n", ret);
 462                 ret = -EIO;
 463         }
 464 exit:
 465         kfree(status);
 466         return ret;
 467 }
 468 EXPORT_SYMBOL_GPL(line6_write_data);
 469
 470 /*
 471         Read Line 6 device serial number.
 472         (POD, TonePort, GuitarPort)
 473 */
 474 int line6_read_serial_number(struct usb_line6 *line6, u32 *serial_number)
 475 {
 476         return line6_read_data(line6, 0x80d0, serial_number,
 477                                sizeof(*serial_number));
 478 }
 479 EXPORT_SYMBOL_GPL(line6_read_serial_number);
 480
 481 /*
 482         Card destructor.
 483 */
 484 static void line6_destruct(struct snd_card *card)
 485 {
 486         struct usb_line6 *line6 = card->private_data;
 487         struct usb_device *usbdev = line6->usbdev;
 488
 489         /* Free buffer memory first. We cannot depend on the existence of private
 490          * data from the (podhd) module, it may be gone already during this call
 491          */
 492         kfree(line6->buffer_message);
 493
 494         kfree(line6->buffer_listen);
 495
 496         /* then free URBs: */
 497         usb_free_urb(line6->urb_listen);
 498         line6->urb_listen = NULL;
 499
 500         /* decrement reference counters: */
 501         usb_put_dev(usbdev);
 502 }
 503
 504 static void line6_get_usb_properties(struct usb_line6 *line6)
 505 {
 506         struct usb_device *usbdev = line6->usbdev;
 507         const struct line6_properties *properties = line6->properties;
 508         int pipe;
 509         struct usb_host_endpoint *ep = NULL;
 510
 511         if (properties->capabilities & LINE6_CAP_CONTROL) {
 512                 if (properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 513                         pipe = usb_rcvintpipe(line6->usbdev,
 514                                 line6->properties->ep_ctrl_r);
 515                 } else {
 516                         pipe = usb_rcvbulkpipe(line6->usbdev,
 517                                 line6->properties->ep_ctrl_r);
 518                 }
 519                 ep = usbdev->ep_in[usb_pipeendpoint(pipe)];
 520         }
 521
 522         /* Control data transfer properties */
 523         if (ep) {
 524                 line6->interval = ep->desc.bInterval;
 525                 line6->max_packet_size = le16_to_cpu(ep->desc.wMaxPacketSize);
 526         } else {
 527                 if (properties->capabilities & LINE6_CAP_CONTROL) {
 528                         dev_err(line6->ifcdev,
 529                                 "endpoint not available, using fallback values");
 530                 }
 531                 line6->interval = LINE6_FALLBACK_INTERVAL;
 532                 line6->max_packet_size = LINE6_FALLBACK_MAXPACKETSIZE;
 533         }
 534
 535         /* Isochronous transfer properties */
 536         if (usbdev->speed == USB_SPEED_LOW) {
 537                 line6->intervals_per_second = USB_LOW_INTERVALS_PER_SECOND;
 538                 line6->iso_buffers = USB_LOW_ISO_BUFFERS;
 539         } else {
 540                 line6->intervals_per_second = USB_HIGH_INTERVALS_PER_SECOND;
 541                 line6->iso_buffers = USB_HIGH_ISO_BUFFERS;
 542         }
 543 }
 544
 545 /* Enable buffering of incoming messages, flush the buffer */
 546 static int line6_hwdep_open(struct snd_hwdep *hw, struct file *file)
 547 {
 548         struct usb_line6 *line6 = hw->private_data;
 549
 550         /* NOTE: hwdep layer provides atomicity here */
 551
 552         line6->messages.active = 1;
 553         line6->messages.nonblock = file->f_flags & O_NONBLOCK ? 1 : 0;
 554
 555         return 0;
 556 }
 557
 558 /* Stop buffering */
 559 static int line6_hwdep_release(struct snd_hwdep *hw, struct file *file)
 560 {
 561         struct usb_line6 *line6 = hw->private_data;
 562
 563         line6->messages.active = 0;
 564
 565         return 0;
 566 }
 567
 568 /* Read from circular buffer, return to user */
 569 static long
 570 line6_hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
 571                                         loff_t *offset)
 572 {
 573         struct usb_line6 *line6 = hwdep->private_data;
 574         long rv = 0;
 575         unsigned int out_count;
 576
 577         if (mutex_lock_interruptible(&line6->messages.read_lock))
 578                 return -ERESTARTSYS;
 579
 580         while (kfifo_len(&line6->messages.fifo) == 0) {
 581                 mutex_unlock(&line6->messages.read_lock);
 582
 583                 if (line6->messages.nonblock)
 584                         return -EAGAIN;
 585
 586                 rv = wait_event_interruptible(
 587                         line6->messages.wait_queue,
 588                         kfifo_len(&line6->messages.fifo) != 0);
 589                 if (rv < 0)
 590                         return rv;
 591
 592                 if (mutex_lock_interruptible(&line6->messages.read_lock))
 593                         return -ERESTARTSYS;
 594         }
 595
 596         if (kfifo_peek_len(&line6->messages.fifo) > count) {
 597                 /* Buffer too small; allow re-read of the current item... */
 598                 rv = -EINVAL;
 599         } else {
 600                 rv = kfifo_to_user(&line6->messages.fifo, buf, count, &out_count);
 601                 if (rv == 0)
 602                         rv = out_count;
 603         }
 604
 605         mutex_unlock(&line6->messages.read_lock);
 606         return rv;
 607 }
 608
 609 /* Write directly (no buffering) to device by user*/
 610 static long
 611 line6_hwdep_write(struct snd_hwdep *hwdep, const char __user *data, long count,
 612                                         loff_t *offset)
 613 {
 614         struct usb_line6 *line6 = hwdep->private_data;
 615         int rv;
 616         char *data_copy;
 617
 618         if (count > line6->max_packet_size * LINE6_RAW_MESSAGES_MAXCOUNT) {
 619                 /* This is an arbitrary limit - still better than nothing... */
 620                 return -EINVAL;
 621         }
 622
 623         data_copy = memdup_user(data, count);
 624         if (IS_ERR(data_copy))
 625                 return PTR_ERR(data_copy);
 626
 627         rv = line6_send_raw_message(line6, data_copy, count);
 628
 629         kfree(data_copy);
 630         return rv;
 631 }
 632
 633 static __poll_t
 634 line6_hwdep_poll(struct snd_hwdep *hwdep, struct file *file, poll_table *wait)
 635 {
 636         __poll_t rv;
 637         struct usb_line6 *line6 = hwdep->private_data;
 638
 639         poll_wait(file, &line6->messages.wait_queue, wait);
 640
 641         mutex_lock(&line6->messages.read_lock);
 642         rv = kfifo_len(&line6->messages.fifo) == 0 ? 0 : EPOLLIN | EPOLLRDNORM;
 643         mutex_unlock(&line6->messages.read_lock);
 644
 645         return rv;
 646 }
 647
 648 static const struct snd_hwdep_ops hwdep_ops = {
 649         .open    = line6_hwdep_open,
 650         .release = line6_hwdep_release,
 651         .read    = line6_hwdep_read,
 652         .write   = line6_hwdep_write,
 653         .poll    = line6_hwdep_poll,
 654 };
 655
 656 /* Insert into circular buffer */
 657 static void line6_hwdep_push_message(struct usb_line6 *line6)
 658 {
 659         if (!line6->messages.active)
 660                 return;
 661
 662         if (kfifo_avail(&line6->messages.fifo) >= line6->message_length) {
 663                 /* No race condition here, there's only one writer */
 664                 kfifo_in(&line6->messages.fifo,
 665                         line6->buffer_message, line6->message_length);
 666         } /* else TODO: signal overflow */
 667
 668         wake_up_interruptible(&line6->messages.wait_queue);
 669 }
 670
 671 static int line6_hwdep_init(struct usb_line6 *line6)
 672 {
 673         int err;
 674         struct snd_hwdep *hwdep;
 675
 676         /* TODO: usb_driver_claim_interface(); */
 677         line6->process_message = line6_hwdep_push_message;
 678         line6->messages.active = 0;
 679         init_waitqueue_head(&line6->messages.wait_queue);
 680         mutex_init(&line6->messages.read_lock);
 681         INIT_KFIFO(line6->messages.fifo);
 682
 683         err = snd_hwdep_new(line6->card, "config", 0, &hwdep);
 684         if (err < 0)
 685                 goto end;
 686         strcpy(hwdep->name, "config");
 687         hwdep->iface = SNDRV_HWDEP_IFACE_LINE6;
 688         hwdep->ops = hwdep_ops;
 689         hwdep->private_data = line6;
 690         hwdep->exclusive = true;
 691
 692 end:
 693         return err;
 694 }
 695
 696 static int line6_init_cap_control(struct usb_line6 *line6)
 697 {
 698         int ret;
 699
 700         /* initialize USB buffers: */
 701         line6->buffer_listen = kmalloc(LINE6_BUFSIZE_LISTEN, GFP_KERNEL);
 702         if (!line6->buffer_listen)
 703                 return -ENOMEM;
 704
 705         line6->urb_listen = usb_alloc_urb(0, GFP_KERNEL);
 706         if (!line6->urb_listen)
 707                 return -ENOMEM;
 708
 709         if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 710                 line6->buffer_message = kmalloc(LINE6_MIDI_MESSAGE_MAXLEN, GFP_KERNEL);
 711                 if (!line6->buffer_message)
 712                         return -ENOMEM;
 713         } else {
 714                 ret = line6_hwdep_init(line6);
 715                 if (ret < 0)
 716                         return ret;
 717         }
 718
 719         ret = line6_start_listen(line6);
 720         if (ret < 0) {
 721                 dev_err(line6->ifcdev, "cannot start listening: %d\n", ret);
 722                 return ret;
 723         }
 724
 725         return 0;
 726 }
 727
 728 static void line6_startup_work(struct work_struct *work)
 729 {
 730         struct usb_line6 *line6 =
 731                 container_of(work, struct usb_line6, startup_work.work);
 732
 733         if (line6->startup)
 734                 line6->startup(line6);
 735 }
 736
 737 /*
 738         Probe USB device.
 739 */
 740 int line6_probe(struct usb_interface *interface,
 741                 const struct usb_device_id *id,
 742                 const char *driver_name,
 743                 const struct line6_properties *properties,
 744                 int (*private_init)(struct usb_line6 *, const struct usb_device_id *id),
 745                 size_t data_size)
 746 {
 747         struct usb_device *usbdev = interface_to_usbdev(interface);
 748         struct snd_card *card;
 749         struct usb_line6 *line6;
 750         int interface_number;
 751         int ret;
 752
 753         if (WARN_ON(data_size < sizeof(*line6)))
 754                 return -EINVAL;
 755
 756         /* we don't handle multiple configurations */
 757         if (usbdev->descriptor.bNumConfigurations != 1)
 758                 return -ENODEV;
 759
 760         ret = snd_card_new(&interface->dev,
 761                            SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
 762                            THIS_MODULE, data_size, &card);
 763         if (ret < 0)
 764                 return ret;
 765
 766         /* store basic data: */
 767         line6 = card->private_data;
 768         line6->card = card;
 769         line6->properties = properties;
 770         line6->usbdev = usbdev;
 771         line6->ifcdev = &interface->dev;
 772         INIT_DELAYED_WORK(&line6->startup_work, line6_startup_work);
 773
 774         strcpy(card->id, properties->id);
 775         strcpy(card->driver, driver_name);
 776         strcpy(card->shortname, properties->name);
 777         sprintf(card->longname, "Line 6 %s at USB %s", properties->name,
 778                 dev_name(line6->ifcdev));
 779         card->private_free = line6_destruct;
 780
 781         usb_set_intfdata(interface, line6);
 782
 783         /* increment reference counters: */
 784         usb_get_dev(usbdev);
 785
 786         /* initialize device info: */
 787         dev_info(&interface->dev, "Line 6 %s found\n", properties->name);
 788
 789         /* query interface number */
 790         interface_number = interface->cur_altsetting->desc.bInterfaceNumber;
 791
 792         /* TODO reserves the bus bandwidth even without actual transfer */
 793         ret = usb_set_interface(usbdev, interface_number,
 794                                 properties->altsetting);
 795         if (ret < 0) {
 796                 dev_err(&interface->dev, "set_interface failed\n");
 797                 goto error;
 798         }
 799
 800         line6_get_usb_properties(line6);
 801
 802         if (properties->capabilities & LINE6_CAP_CONTROL) {
 803                 ret = line6_init_cap_control(line6);
 804                 if (ret < 0)
 805                         goto error;
 806         }
 807
 808         /* initialize device data based on device: */
 809         ret = private_init(line6, id);
 810         if (ret < 0)
 811                 goto error;
 812
 813         /* creation of additional special files should go here */
 814
 815         dev_info(&interface->dev, "Line 6 %s now attached\n",
 816                  properties->name);
 817
 818         return 0;
 819
 820  error:
 821         /* we can call disconnect callback here because no close-sync is
 822          * needed yet at this point
 823          */
 824         line6_disconnect(interface);
 825         return ret;
 826 }
 827 EXPORT_SYMBOL_GPL(line6_probe);
 828
 829 /*
 830         Line 6 device disconnected.
 831 */
 832 void line6_disconnect(struct usb_interface *interface)
 833 {
 834         struct usb_line6 *line6 = usb_get_intfdata(interface);
 835         struct usb_device *usbdev = interface_to_usbdev(interface);
 836
 837         if (!line6)
 838                 return;
 839
 840         if (WARN_ON(usbdev != line6->usbdev))
 841                 return;
 842
 843         cancel_delayed_work_sync(&line6->startup_work);
 844
 845         if (line6->urb_listen != NULL)
 846                 line6_stop_listen(line6);
 847
 848         snd_card_disconnect(line6->card);
 849         if (line6->line6pcm)
 850                 line6_pcm_disconnect(line6->line6pcm);
 851         if (line6->disconnect)
 852                 line6->disconnect(line6);
 853
 854         dev_info(&interface->dev, "Line 6 %s now disconnected\n",
 855                  line6->properties->name);
 856
 857         /* make sure the device isn't destructed twice: */
 858         usb_set_intfdata(interface, NULL);
 859
 860         snd_card_free_when_closed(line6->card);
 861 }
 862 EXPORT_SYMBOL_GPL(line6_disconnect);
 863
 864 #ifdef CONFIG_PM
 865
 866 /*
 867         Suspend Line 6 device.
 868 */
 869 int line6_suspend(struct usb_interface *interface, pm_message_t message)
 870 {
 871         struct usb_line6 *line6 = usb_get_intfdata(interface);
 872         struct snd_line6_pcm *line6pcm = line6->line6pcm;
 873
 874         snd_power_change_state(line6->card, SNDRV_CTL_POWER_D3hot);
 875
 876         if (line6->properties->capabilities & LINE6_CAP_CONTROL)
 877                 line6_stop_listen(line6);
 878
 879         if (line6pcm != NULL)
 880                 line6pcm->flags = 0;
 881
 882         return 0;
 883 }
 884 EXPORT_SYMBOL_GPL(line6_suspend);
 885
 886 /*
 887         Resume Line 6 device.
 888 */
 889 int line6_resume(struct usb_interface *interface)
 890 {
 891         struct usb_line6 *line6 = usb_get_intfdata(interface);
 892
 893         if (line6->properties->capabilities & LINE6_CAP_CONTROL)
 894                 line6_start_listen(line6);
 895
 896         snd_power_change_state(line6->card, SNDRV_CTL_POWER_D0);
 897         return 0;
 898 }
 899 EXPORT_SYMBOL_GPL(line6_resume);
 900
 901 #endif /* CONFIG_PM */
 902
 903 MODULE_AUTHOR(DRIVER_AUTHOR);
 904 MODULE_DESCRIPTION(DRIVER_DESC);
 905 MODULE_LICENSE("GPL");
 906