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 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 EXPORT_SYMBOL_GPL(line6_send_raw_message);
 136
 137 /*
 138         Notification of completion of asynchronous request transmission.
 139 */
 140 static void line6_async_request_sent(struct urb *urb)
 141 {
 142         struct message *msg = (struct message *)urb->context;
 143
 144         if (msg->done >= msg->size) {
 145                 usb_free_urb(urb);
 146                 kfree(msg);
 147         } else
 148                 line6_send_raw_message_async_part(msg, urb);
 149 }
 150
 151 /*
 152         Asynchronously send part of a raw message.
 153 */
 154 static int line6_send_raw_message_async_part(struct message *msg,
 155                                              struct urb *urb)
 156 {
 157         int retval;
 158         struct usb_line6 *line6 = msg->line6;
 159         int done = msg->done;
 160         int bytes = min(msg->size - done, line6->max_packet_size);
 161
 162         if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 163                 usb_fill_int_urb(urb, line6->usbdev,
 164                         usb_sndintpipe(line6->usbdev, line6->properties->ep_ctrl_w),
 165                         (char *)msg->buffer + done, bytes,
 166                         line6_async_request_sent, msg, line6->interval);
 167         } else {
 168                 usb_fill_bulk_urb(urb, line6->usbdev,
 169                         usb_sndbulkpipe(line6->usbdev, line6->properties->ep_ctrl_w),
 170                         (char *)msg->buffer + done, bytes,
 171                         line6_async_request_sent, msg);
 172         }
 173
 174         msg->done += bytes;
 175
 176         /* sanity checks of EP before actually submitting */
 177         retval = usb_urb_ep_type_check(urb);
 178         if (retval < 0)
 179                 goto error;
 180
 181         retval = usb_submit_urb(urb, GFP_ATOMIC);
 182         if (retval < 0)
 183                 goto error;
 184
 185         return 0;
 186
 187  error:
 188         dev_err(line6->ifcdev, "%s: usb_submit_urb failed (%d)\n",
 189                 __func__, retval);
 190         usb_free_urb(urb);
 191         kfree(msg);
 192         return retval;
 193 }
 194
 195 /*
 196         Asynchronously send raw message.
 197 */
 198 int line6_send_raw_message_async(struct usb_line6 *line6, const char *buffer,
 199                                  int size)
 200 {
 201         struct message *msg;
 202         struct urb *urb;
 203
 204         /* create message: */
 205         msg = kmalloc(sizeof(struct message), GFP_ATOMIC);
 206         if (msg == NULL)
 207                 return -ENOMEM;
 208
 209         /* create URB: */
 210         urb = usb_alloc_urb(0, GFP_ATOMIC);
 211
 212         if (urb == NULL) {
 213                 kfree(msg);
 214                 return -ENOMEM;
 215         }
 216
 217         /* set message data: */
 218         msg->line6 = line6;
 219         msg->buffer = buffer;
 220         msg->size = size;
 221         msg->done = 0;
 222
 223         /* start sending: */
 224         return line6_send_raw_message_async_part(msg, urb);
 225 }
 226 EXPORT_SYMBOL_GPL(line6_send_raw_message_async);
 227
 228 /*
 229         Send asynchronous device version request.
 230 */
 231 int line6_version_request_async(struct usb_line6 *line6)
 232 {
 233         char *buffer;
 234         int retval;
 235
 236         buffer = kmemdup(line6_request_version,
 237                         sizeof(line6_request_version), GFP_ATOMIC);
 238         if (buffer == NULL)
 239                 return -ENOMEM;
 240
 241         retval = line6_send_raw_message_async(line6, buffer,
 242                                               sizeof(line6_request_version));
 243         kfree(buffer);
 244         return retval;
 245 }
 246 EXPORT_SYMBOL_GPL(line6_version_request_async);
 247
 248 /*
 249         Send sysex message in pieces of wMaxPacketSize bytes.
 250 */
 251 int line6_send_sysex_message(struct usb_line6 *line6, const char *buffer,
 252                              int size)
 253 {
 254         return line6_send_raw_message(line6, buffer,
 255                                       size + SYSEX_EXTRA_SIZE) -
 256             SYSEX_EXTRA_SIZE;
 257 }
 258 EXPORT_SYMBOL_GPL(line6_send_sysex_message);
 259
 260 /*
 261         Allocate buffer for sysex message and prepare header.
 262         @param code sysex message code
 263         @param size number of bytes between code and sysex end
 264 */
 265 char *line6_alloc_sysex_buffer(struct usb_line6 *line6, int code1, int code2,
 266                                int size)
 267 {
 268         char *buffer = kmalloc(size + SYSEX_EXTRA_SIZE, GFP_ATOMIC);
 269
 270         if (!buffer)
 271                 return NULL;
 272
 273         buffer[0] = LINE6_SYSEX_BEGIN;
 274         memcpy(buffer + 1, line6_midi_id, sizeof(line6_midi_id));
 275         buffer[sizeof(line6_midi_id) + 1] = code1;
 276         buffer[sizeof(line6_midi_id) + 2] = code2;
 277         buffer[sizeof(line6_midi_id) + 3 + size] = LINE6_SYSEX_END;
 278         return buffer;
 279 }
 280 EXPORT_SYMBOL_GPL(line6_alloc_sysex_buffer);
 281
 282 /*
 283         Notification of data received from the Line 6 device.
 284 */
 285 static void line6_data_received(struct urb *urb)
 286 {
 287         struct usb_line6 *line6 = (struct usb_line6 *)urb->context;
 288         struct midi_buffer *mb = &line6->line6midi->midibuf_in;
 289         int done;
 290
 291         if (urb->status == -ESHUTDOWN)
 292                 return;
 293
 294         if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 295                 done =
 296                         line6_midibuf_write(mb, urb->transfer_buffer, urb->actual_length);
 297
 298                 if (done < urb->actual_length) {
 299                         line6_midibuf_ignore(mb, done);
 300                         dev_dbg(line6->ifcdev, "%d %d buffer overflow - message skipped\n",
 301                                 done, urb->actual_length);
 302                 }
 303
 304                 for (;;) {
 305                         done =
 306                                 line6_midibuf_read(mb, line6->buffer_message,
 307                                                 LINE6_MIDI_MESSAGE_MAXLEN);
 308
 309                         if (done <= 0)
 310                                 break;
 311
 312                         line6->message_length = done;
 313                         line6_midi_receive(line6, line6->buffer_message, done);
 314
 315                         if (line6->process_message)
 316                                 line6->process_message(line6);
 317                 }
 318         } else {
 319                 line6->buffer_message = urb->transfer_buffer;
 320                 line6->message_length = urb->actual_length;
 321                 if (line6->process_message)
 322                         line6->process_message(line6);
 323                 line6->buffer_message = NULL;
 324         }
 325
 326         line6_start_listen(line6);
 327 }
 328
 329 #define LINE6_READ_WRITE_STATUS_DELAY 2  /* milliseconds */
 330 #define LINE6_READ_WRITE_MAX_RETRIES 50
 331
 332 /*
 333         Read data from device.
 334 */
 335 int line6_read_data(struct usb_line6 *line6, unsigned address, void *data,
 336                     unsigned datalen)
 337 {
 338         struct usb_device *usbdev = line6->usbdev;
 339         int ret;
 340         unsigned char *len;
 341         unsigned count;
 342
 343         if (address > 0xffff || datalen > 0xff)
 344                 return -EINVAL;
 345
 346         len = kmalloc(1, GFP_KERNEL);
 347         if (!len)
 348                 return -ENOMEM;
 349
 350         /* query the serial number: */
 351         ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
 352                               USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 353                               (datalen << 8) | 0x21, address,
 354                               NULL, 0, LINE6_TIMEOUT * HZ);
 355
 356         if (ret < 0) {
 357                 dev_err(line6->ifcdev, "read request failed (error %d)\n", ret);
 358                 goto exit;
 359         }
 360
 361         /* Wait for data length. We'll get 0xff until length arrives. */
 362         for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
 363                 mdelay(LINE6_READ_WRITE_STATUS_DELAY);
 364
 365                 ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
 366                                       USB_TYPE_VENDOR | USB_RECIP_DEVICE |
 367                                       USB_DIR_IN,
 368                                       0x0012, 0x0000, len, 1,
 369                                       LINE6_TIMEOUT * HZ);
 370                 if (ret < 0) {
 371                         dev_err(line6->ifcdev,
 372                                 "receive length failed (error %d)\n", ret);
 373                         goto exit;
 374                 }
 375
 376                 if (*len != 0xff)
 377                         break;
 378         }
 379
 380         ret = -EIO;
 381         if (*len == 0xff) {
 382                 dev_err(line6->ifcdev, "read failed after %d retries\n",
 383                         count);
 384                 goto exit;
 385         } else if (*len != datalen) {
 386                 /* should be equal or something went wrong */
 387                 dev_err(line6->ifcdev,
 388                         "length mismatch (expected %d, got %d)\n",
 389                         (int)datalen, (int)*len);
 390                 goto exit;
 391         }
 392
 393         /* receive the result: */
 394         ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
 395                               USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
 396                               0x0013, 0x0000, data, datalen,
 397                               LINE6_TIMEOUT * HZ);
 398
 399         if (ret < 0)
 400                 dev_err(line6->ifcdev, "read failed (error %d)\n", ret);
 401
 402 exit:
 403         kfree(len);
 404         return ret;
 405 }
 406 EXPORT_SYMBOL_GPL(line6_read_data);
 407
 408 /*
 409         Write data to device.
 410 */
 411 int line6_write_data(struct usb_line6 *line6, unsigned address, void *data,
 412                      unsigned datalen)
 413 {
 414         struct usb_device *usbdev = line6->usbdev;
 415         int ret;
 416         unsigned char *status;
 417         int count;
 418
 419         if (address > 0xffff || datalen > 0xffff)
 420                 return -EINVAL;
 421
 422         status = kmalloc(1, GFP_KERNEL);
 423         if (!status)
 424                 return -ENOMEM;
 425
 426         ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
 427                               USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
 428                               0x0022, address, data, datalen,
 429                               LINE6_TIMEOUT * HZ);
 430
 431         if (ret < 0) {
 432                 dev_err(line6->ifcdev,
 433                         "write request failed (error %d)\n", ret);
 434                 goto exit;
 435         }
 436
 437         for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
 438                 mdelay(LINE6_READ_WRITE_STATUS_DELAY);
 439
 440                 ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
 441                                       0x67,
 442                                       USB_TYPE_VENDOR | USB_RECIP_DEVICE |
 443                                       USB_DIR_IN,
 444                                       0x0012, 0x0000,
 445                                       status, 1, LINE6_TIMEOUT * HZ);
 446
 447                 if (ret < 0) {
 448                         dev_err(line6->ifcdev,
 449                                 "receiving status failed (error %d)\n", ret);
 450                         goto exit;
 451                 }
 452
 453                 if (*status != 0xff)
 454                         break;
 455         }
 456
 457         if (*status == 0xff) {
 458                 dev_err(line6->ifcdev, "write failed after %d retries\n",
 459                         count);
 460                 ret = -EIO;
 461         } else if (*status != 0) {
 462                 dev_err(line6->ifcdev, "write failed (error %d)\n", ret);
 463                 ret = -EIO;
 464         }
 465 exit:
 466         kfree(status);
 467         return ret;
 468 }
 469 EXPORT_SYMBOL_GPL(line6_write_data);
 470
 471 /*
 472         Read Line 6 device serial number.
 473         (POD, TonePort, GuitarPort)
 474 */
 475 int line6_read_serial_number(struct usb_line6 *line6, u32 *serial_number)
 476 {
 477         return line6_read_data(line6, 0x80d0, serial_number,
 478                                sizeof(*serial_number));
 479 }
 480 EXPORT_SYMBOL_GPL(line6_read_serial_number);
 481
 482 /*
 483         Card destructor.
 484 */
 485 static void line6_destruct(struct snd_card *card)
 486 {
 487         struct usb_line6 *line6 = card->private_data;
 488         struct usb_device *usbdev = line6->usbdev;
 489
 490         /* Free buffer memory first. We cannot depend on the existence of private
 491          * data from the (podhd) module, it may be gone already during this call
 492          */
 493         kfree(line6->buffer_message);
 494
 495         kfree(line6->buffer_listen);
 496
 497         /* then free URBs: */
 498         usb_free_urb(line6->urb_listen);
 499         line6->urb_listen = NULL;
 500
 501         /* decrement reference counters: */
 502         usb_put_dev(usbdev);
 503 }
 504
 505 static void line6_get_usb_properties(struct usb_line6 *line6)
 506 {
 507         struct usb_device *usbdev = line6->usbdev;
 508         const struct line6_properties *properties = line6->properties;
 509         int pipe;
 510         struct usb_host_endpoint *ep = NULL;
 511
 512         if (properties->capabilities & LINE6_CAP_CONTROL) {
 513                 if (properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 514                         pipe = usb_rcvintpipe(line6->usbdev,
 515                                 line6->properties->ep_ctrl_r);
 516                 } else {
 517                         pipe = usb_rcvbulkpipe(line6->usbdev,
 518                                 line6->properties->ep_ctrl_r);
 519                 }
 520                 ep = usbdev->ep_in[usb_pipeendpoint(pipe)];
 521         }
 522
 523         /* Control data transfer properties */
 524         if (ep) {
 525                 line6->interval = ep->desc.bInterval;
 526                 line6->max_packet_size = le16_to_cpu(ep->desc.wMaxPacketSize);
 527         } else {
 528                 if (properties->capabilities & LINE6_CAP_CONTROL) {
 529                         dev_err(line6->ifcdev,
 530                                 "endpoint not available, using fallback values");
 531                 }
 532                 line6->interval = LINE6_FALLBACK_INTERVAL;
 533                 line6->max_packet_size = LINE6_FALLBACK_MAXPACKETSIZE;
 534         }
 535
 536         /* Isochronous transfer properties */
 537         if (usbdev->speed == USB_SPEED_LOW) {
 538                 line6->intervals_per_second = USB_LOW_INTERVALS_PER_SECOND;
 539                 line6->iso_buffers = USB_LOW_ISO_BUFFERS;
 540         } else {
 541                 line6->intervals_per_second = USB_HIGH_INTERVALS_PER_SECOND;
 542                 line6->iso_buffers = USB_HIGH_ISO_BUFFERS;
 543         }
 544 }
 545
 546 /* Enable buffering of incoming messages, flush the buffer */
 547 static int line6_hwdep_open(struct snd_hwdep *hw, struct file *file)
 548 {
 549         struct usb_line6 *line6 = hw->private_data;
 550
 551         /* NOTE: hwdep layer provides atomicity here */
 552
 553         line6->messages.active = 1;
 554         line6->messages.nonblock = file->f_flags & O_NONBLOCK ? 1 : 0;
 555
 556         return 0;
 557 }
 558
 559 /* Stop buffering */
 560 static int line6_hwdep_release(struct snd_hwdep *hw, struct file *file)
 561 {
 562         struct usb_line6 *line6 = hw->private_data;
 563
 564         line6->messages.active = 0;
 565
 566         return 0;
 567 }
 568
 569 /* Read from circular buffer, return to user */
 570 static long
 571 line6_hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count,
 572                                         loff_t *offset)
 573 {
 574         struct usb_line6 *line6 = hwdep->private_data;
 575         long rv = 0;
 576         unsigned int out_count;
 577
 578         if (mutex_lock_interruptible(&line6->messages.read_lock))
 579                 return -ERESTARTSYS;
 580
 581         while (kfifo_len(&line6->messages.fifo) == 0) {
 582                 mutex_unlock(&line6->messages.read_lock);
 583
 584                 if (line6->messages.nonblock)
 585                         return -EAGAIN;
 586
 587                 rv = wait_event_interruptible(
 588                         line6->messages.wait_queue,
 589                         kfifo_len(&line6->messages.fifo) != 0);
 590                 if (rv < 0)
 591                         return rv;
 592
 593                 if (mutex_lock_interruptible(&line6->messages.read_lock))
 594                         return -ERESTARTSYS;
 595         }
 596
 597         if (kfifo_peek_len(&line6->messages.fifo) > count) {
 598                 /* Buffer too small; allow re-read of the current item... */
 599                 rv = -EINVAL;
 600         } else {
 601                 rv = kfifo_to_user(&line6->messages.fifo, buf, count, &out_count);
 602                 if (rv == 0)
 603                         rv = out_count;
 604         }
 605
 606         mutex_unlock(&line6->messages.read_lock);
 607         return rv;
 608 }
 609
 610 /* Write directly (no buffering) to device by user*/
 611 static long
 612 line6_hwdep_write(struct snd_hwdep *hwdep, const char __user *data, long count,
 613                                         loff_t *offset)
 614 {
 615         struct usb_line6 *line6 = hwdep->private_data;
 616         int rv;
 617         char *data_copy;
 618
 619         if (count > line6->max_packet_size * LINE6_RAW_MESSAGES_MAXCOUNT) {
 620                 /* This is an arbitrary limit - still better than nothing... */
 621                 return -EINVAL;
 622         }
 623
 624         data_copy = memdup_user(data, count);
 625         if (IS_ERR(data_copy))
 626                 return PTR_ERR(data_copy);
 627
 628         rv = line6_send_raw_message(line6, data_copy, count);
 629
 630         kfree(data_copy);
 631         return rv;
 632 }
 633
 634 static __poll_t
 635 line6_hwdep_poll(struct snd_hwdep *hwdep, struct file *file, poll_table *wait)
 636 {
 637         __poll_t rv;
 638         struct usb_line6 *line6 = hwdep->private_data;
 639
 640         poll_wait(file, &line6->messages.wait_queue, wait);
 641
 642         mutex_lock(&line6->messages.read_lock);
 643         rv = kfifo_len(&line6->messages.fifo) == 0 ? 0 : EPOLLIN | EPOLLRDNORM;
 644         mutex_unlock(&line6->messages.read_lock);
 645
 646         return rv;
 647 }
 648
 649 static const struct snd_hwdep_ops hwdep_ops = {
 650         .open    = line6_hwdep_open,
 651         .release = line6_hwdep_release,
 652         .read    = line6_hwdep_read,
 653         .write   = line6_hwdep_write,
 654         .poll    = line6_hwdep_poll,
 655 };
 656
 657 /* Insert into circular buffer */
 658 static void line6_hwdep_push_message(struct usb_line6 *line6)
 659 {
 660         if (!line6->messages.active)
 661                 return;
 662
 663         if (kfifo_avail(&line6->messages.fifo) >= line6->message_length) {
 664                 /* No race condition here, there's only one writer */
 665                 kfifo_in(&line6->messages.fifo,
 666                         line6->buffer_message, line6->message_length);
 667         } /* else TODO: signal overflow */
 668
 669         wake_up_interruptible(&line6->messages.wait_queue);
 670 }
 671
 672 static int line6_hwdep_init(struct usb_line6 *line6)
 673 {
 674         int err;
 675         struct snd_hwdep *hwdep;
 676
 677         /* TODO: usb_driver_claim_interface(); */
 678         line6->process_message = line6_hwdep_push_message;
 679         line6->messages.active = 0;
 680         init_waitqueue_head(&line6->messages.wait_queue);
 681         mutex_init(&line6->messages.read_lock);
 682         INIT_KFIFO(line6->messages.fifo);
 683
 684         err = snd_hwdep_new(line6->card, "config", 0, &hwdep);
 685         if (err < 0)
 686                 goto end;
 687         strcpy(hwdep->name, "config");
 688         hwdep->iface = SNDRV_HWDEP_IFACE_LINE6;
 689         hwdep->ops = hwdep_ops;
 690         hwdep->private_data = line6;
 691         hwdep->exclusive = true;
 692
 693 end:
 694         return err;
 695 }
 696
 697 static int line6_init_cap_control(struct usb_line6 *line6)
 698 {
 699         int ret;
 700
 701         /* initialize USB buffers: */
 702         line6->buffer_listen = kmalloc(LINE6_BUFSIZE_LISTEN, GFP_KERNEL);
 703         if (!line6->buffer_listen)
 704                 return -ENOMEM;
 705
 706         line6->urb_listen = usb_alloc_urb(0, GFP_KERNEL);
 707         if (!line6->urb_listen)
 708                 return -ENOMEM;
 709
 710         if (line6->properties->capabilities & LINE6_CAP_CONTROL_MIDI) {
 711                 line6->buffer_message = kmalloc(LINE6_MIDI_MESSAGE_MAXLEN, GFP_KERNEL);
 712                 if (!line6->buffer_message)
 713                         return -ENOMEM;
 714         } else {
 715                 ret = line6_hwdep_init(line6);
 716                 if (ret < 0)
 717                         return ret;
 718         }
 719
 720         ret = line6_start_listen(line6);
 721         if (ret < 0) {
 722                 dev_err(line6->ifcdev, "cannot start listening: %d\n", ret);
 723                 return ret;
 724         }
 725
 726         return 0;
 727 }
 728
 729 static void line6_startup_work(struct work_struct *work)
 730 {
 731         struct usb_line6 *line6 =
 732                 container_of(work, struct usb_line6, startup_work.work);
 733
 734         if (line6->startup)
 735                 line6->startup(line6);
 736 }
 737
 738 /*
 739         Probe USB device.
 740 */
 741 int line6_probe(struct usb_interface *interface,
 742                 const struct usb_device_id *id,
 743                 const char *driver_name,
 744                 const struct line6_properties *properties,
 745                 int (*private_init)(struct usb_line6 *, const struct usb_device_id *id),
 746                 size_t data_size)
 747 {
 748         struct usb_device *usbdev = interface_to_usbdev(interface);
 749         struct snd_card *card;
 750         struct usb_line6 *line6;
 751         int interface_number;
 752         int ret;
 753
 754         if (WARN_ON(data_size < sizeof(*line6)))
 755                 return -EINVAL;
 756
 757         /* we don't handle multiple configurations */
 758         if (usbdev->descriptor.bNumConfigurations != 1)
 759                 return -ENODEV;
 760
 761         ret = snd_card_new(&interface->dev,
 762                            SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
 763                            THIS_MODULE, data_size, &card);
 764         if (ret < 0)
 765                 return ret;
 766
 767         /* store basic data: */
 768         line6 = card->private_data;
 769         line6->card = card;
 770         line6->properties = properties;
 771         line6->usbdev = usbdev;
 772         line6->ifcdev = &interface->dev;
 773         INIT_DELAYED_WORK(&line6->startup_work, line6_startup_work);
 774
 775         strcpy(card->id, properties->id);
 776         strcpy(card->driver, driver_name);
 777         strcpy(card->shortname, properties->name);
 778         sprintf(card->longname, "Line 6 %s at USB %s", properties->name,
 779                 dev_name(line6->ifcdev));
 780         card->private_free = line6_destruct;
 781
 782         usb_set_intfdata(interface, line6);
 783
 784         /* increment reference counters: */
 785         usb_get_dev(usbdev);
 786
 787         /* initialize device info: */
 788         dev_info(&interface->dev, "Line 6 %s found\n", properties->name);
 789
 790         /* query interface number */
 791         interface_number = interface->cur_altsetting->desc.bInterfaceNumber;
 792
 793         /* TODO reserves the bus bandwidth even without actual transfer */
 794         ret = usb_set_interface(usbdev, interface_number,
 795                                 properties->altsetting);
 796         if (ret < 0) {
 797                 dev_err(&interface->dev, "set_interface failed\n");
 798                 goto error;
 799         }
 800
 801         line6_get_usb_properties(line6);
 802
 803         if (properties->capabilities & LINE6_CAP_CONTROL) {
 804                 ret = line6_init_cap_control(line6);
 805                 if (ret < 0)
 806                         goto error;
 807         }
 808
 809         /* initialize device data based on device: */
 810         ret = private_init(line6, id);
 811         if (ret < 0)
 812                 goto error;
 813
 814         /* creation of additional special files should go here */
 815
 816         dev_info(&interface->dev, "Line 6 %s now attached\n",
 817                  properties->name);
 818
 819         return 0;
 820
 821  error:
 822         /* we can call disconnect callback here because no close-sync is
 823          * needed yet at this point
 824          */
 825         line6_disconnect(interface);
 826         return ret;
 827 }
 828 EXPORT_SYMBOL_GPL(line6_probe);
 829
 830 /*
 831         Line 6 device disconnected.
 832 */
 833 void line6_disconnect(struct usb_interface *interface)
 834 {
 835         struct usb_line6 *line6 = usb_get_intfdata(interface);
 836         struct usb_device *usbdev = interface_to_usbdev(interface);
 837
 838         if (!line6)
 839                 return;
 840
 841         if (WARN_ON(usbdev != line6->usbdev))
 842                 return;
 843
 844         cancel_delayed_work_sync(&line6->startup_work);
 845
 846         if (line6->urb_listen != NULL)
 847                 line6_stop_listen(line6);
 848
 849         snd_card_disconnect(line6->card);
 850         if (line6->line6pcm)
 851                 line6_pcm_disconnect(line6->line6pcm);
 852         if (line6->disconnect)
 853                 line6->disconnect(line6);
 854
 855         dev_info(&interface->dev, "Line 6 %s now disconnected\n",
 856                  line6->properties->name);
 857
 858         /* make sure the device isn't destructed twice: */
 859         usb_set_intfdata(interface, NULL);
 860
 861         snd_card_free_when_closed(line6->card);
 862 }
 863 EXPORT_SYMBOL_GPL(line6_disconnect);
 864
 865 #ifdef CONFIG_PM
 866
 867 /*
 868         Suspend Line 6 device.
 869 */
 870 int line6_suspend(struct usb_interface *interface, pm_message_t message)
 871 {
 872         struct usb_line6 *line6 = usb_get_intfdata(interface);
 873         struct snd_line6_pcm *line6pcm = line6->line6pcm;
 874
 875         snd_power_change_state(line6->card, SNDRV_CTL_POWER_D3hot);
 876
 877         if (line6->properties->capabilities & LINE6_CAP_CONTROL)
 878                 line6_stop_listen(line6);
 879
 880         if (line6pcm != NULL)
 881                 line6pcm->flags = 0;
 882
 883         return 0;
 884 }
 885 EXPORT_SYMBOL_GPL(line6_suspend);
 886
 887 /*
 888         Resume Line 6 device.
 889 */
 890 int line6_resume(struct usb_interface *interface)
 891 {
 892         struct usb_line6 *line6 = usb_get_intfdata(interface);
 893
 894         if (line6->properties->capabilities & LINE6_CAP_CONTROL)
 895                 line6_start_listen(line6);
 896
 897         snd_power_change_state(line6->card, SNDRV_CTL_POWER_D0);
 898         return 0;
 899 }
 900 EXPORT_SYMBOL_GPL(line6_resume);
 901
 902 #endif /* CONFIG_PM */
 903
 904 MODULE_AUTHOR(DRIVER_AUTHOR);
 905 MODULE_DESCRIPTION(DRIVER_DESC);
 906 MODULE_LICENSE("GPL");
 907