drivers/usb/gadget/f_audio.c

   1 /*
   2  * f_audio.c -- USB Audio class function driver
   3   *
   4  * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
   5  * Copyright (C) 2008 Analog Devices, Inc
   6  *
   7  * Enter bugs at http://blackfin.uclinux.org/
   8  *
   9  * Licensed under the GPL-2 or later.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/device.h>
  14 #include <asm/atomic.h>
  15
  16 #include "u_audio.h"
  17
  18 #define OUT_EP_MAX_PACKET_SIZE  200
  19 static int req_buf_size = OUT_EP_MAX_PACKET_SIZE;
  20 module_param(req_buf_size, int, S_IRUGO);
  21 MODULE_PARM_DESC(req_buf_size, "ISO OUT endpoint request buffer size");
  22
  23 static int req_count = 256;
  24 module_param(req_count, int, S_IRUGO);
  25 MODULE_PARM_DESC(req_count, "ISO OUT endpoint request count");
  26
  27 static int audio_buf_size = 48000;
  28 module_param(audio_buf_size, int, S_IRUGO);
  29 MODULE_PARM_DESC(audio_buf_size, "Audio buffer size");
  30
  31 /*
  32  * DESCRIPTORS ... most are static, but strings and full
  33  * configuration descriptors are built on demand.
  34  */
  35
  36 /*
  37  * We have two interfaces- AudioControl and AudioStreaming
  38  * TODO: only supcard playback currently
  39  */
  40 #define F_AUDIO_AC_INTERFACE    0
  41 #define F_AUDIO_AS_INTERFACE    1
  42 #define F_AUDIO_NUM_INTERFACES  2
  43
  44 /* B.3.1  Standard AC Interface Descriptor */
  45 static struct usb_interface_descriptor ac_interface_desc __initdata = {
  46         .bLength =              USB_DT_INTERFACE_SIZE,
  47         .bDescriptorType =      USB_DT_INTERFACE,
  48         .bNumEndpoints =        0,
  49         .bInterfaceClass =      USB_CLASS_AUDIO,
  50         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOCONTROL,
  51 };
  52
  53 DECLARE_USB_AC_HEADER_DESCRIPTOR(2);
  54
  55 #define USB_DT_AC_HEADER_LENGH  USB_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
  56 /* B.3.2  Class-Specific AC Interface Descriptor */
  57 static struct usb_ac_header_descriptor_2 ac_header_desc = {
  58         .bLength =              USB_DT_AC_HEADER_LENGH,
  59         .bDescriptorType =      USB_DT_CS_INTERFACE,
  60         .bDescriptorSubtype =   HEADER,
  61         .bcdADC =               __constant_cpu_to_le16(0x0100),
  62         .wTotalLength =         __constant_cpu_to_le16(USB_DT_AC_HEADER_LENGH),
  63         .bInCollection =        F_AUDIO_NUM_INTERFACES,
  64         .baInterfaceNr = {
  65                 [0] =           F_AUDIO_AC_INTERFACE,
  66                 [1] =           F_AUDIO_AS_INTERFACE,
  67         }
  68 };
  69
  70 #define INPUT_TERMINAL_ID       1
  71 static struct usb_input_terminal_descriptor input_terminal_desc = {
  72         .bLength =              USB_DT_AC_INPUT_TERMINAL_SIZE,
  73         .bDescriptorType =      USB_DT_CS_INTERFACE,
  74         .bDescriptorSubtype =   INPUT_TERMINAL,
  75         .bTerminalID =          INPUT_TERMINAL_ID,
  76         .wTerminalType =        USB_AC_TERMINAL_STREAMING,
  77         .bAssocTerminal =       0,
  78         .wChannelConfig =       0x3,
  79 };
  80
  81 DECLARE_USB_AC_FEATURE_UNIT_DESCRIPTOR(0);
  82
  83 #define FEATURE_UNIT_ID         2
  84 static struct usb_ac_feature_unit_descriptor_0 feature_unit_desc = {
  85         .bLength                = USB_DT_AC_FEATURE_UNIT_SIZE(0),
  86         .bDescriptorType        = USB_DT_CS_INTERFACE,
  87         .bDescriptorSubtype     = FEATURE_UNIT,
  88         .bUnitID                = FEATURE_UNIT_ID,
  89         .bSourceID              = INPUT_TERMINAL_ID,
  90         .bControlSize           = 2,
  91         .bmaControls[0]         = (FU_MUTE | FU_VOLUME),
  92 };
  93
  94 static struct usb_audio_control mute_control = {
  95         .list = LIST_HEAD_INIT(mute_control.list),
  96         .name = "Mute Control",
  97         .type = MUTE_CONTROL,
  98         /* Todo: add real Mute control code */
  99         .set = generic_set_cmd,
 100         .get = generic_get_cmd,
 101 };
 102
 103 static struct usb_audio_control volume_control = {
 104         .list = LIST_HEAD_INIT(volume_control.list),
 105         .name = "Volume Control",
 106         .type = VOLUME_CONTROL,
 107         /* Todo: add real Volume control code */
 108         .set = generic_set_cmd,
 109         .get = generic_get_cmd,
 110 };
 111
 112 static struct usb_audio_control_selector feature_unit = {
 113         .list = LIST_HEAD_INIT(feature_unit.list),
 114         .id = FEATURE_UNIT_ID,
 115         .name = "Mute & Volume Control",
 116         .type = FEATURE_UNIT,
 117         .desc = (struct usb_descriptor_header *)&feature_unit_desc,
 118 };
 119
 120 #define OUTPUT_TERMINAL_ID      3
 121 static struct usb_output_terminal_descriptor output_terminal_desc = {
 122         .bLength                = USB_DT_AC_OUTPUT_TERMINAL_SIZE,
 123         .bDescriptorType        = USB_DT_CS_INTERFACE,
 124         .bDescriptorSubtype     = OUTPUT_TERMINAL,
 125         .bTerminalID            = OUTPUT_TERMINAL_ID,
 126         .wTerminalType          = USB_AC_OUTPUT_TERMINAL_SPEAKER,
 127         .bAssocTerminal         = FEATURE_UNIT_ID,
 128         .bSourceID              = FEATURE_UNIT_ID,
 129 };
 130
 131 /* B.4.1  Standard AS Interface Descriptor */
 132 static struct usb_interface_descriptor as_interface_alt_0_desc = {
 133         .bLength =              USB_DT_INTERFACE_SIZE,
 134         .bDescriptorType =      USB_DT_INTERFACE,
 135         .bAlternateSetting =    0,
 136         .bNumEndpoints =        0,
 137         .bInterfaceClass =      USB_CLASS_AUDIO,
 138         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 139 };
 140
 141 static struct usb_interface_descriptor as_interface_alt_1_desc = {
 142         .bLength =              USB_DT_INTERFACE_SIZE,
 143         .bDescriptorType =      USB_DT_INTERFACE,
 144         .bAlternateSetting =    1,
 145         .bNumEndpoints =        1,
 146         .bInterfaceClass =      USB_CLASS_AUDIO,
 147         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 148 };
 149
 150 /* B.4.2  Class-Specific AS Interface Descriptor */
 151 static struct usb_as_header_descriptor as_header_desc = {
 152         .bLength =              USB_DT_AS_HEADER_SIZE,
 153         .bDescriptorType =      USB_DT_CS_INTERFACE,
 154         .bDescriptorSubtype =   AS_GENERAL,
 155         .bTerminalLink =        INPUT_TERMINAL_ID,
 156         .bDelay =               1,
 157         .wFormatTag =           USB_AS_AUDIO_FORMAT_TYPE_I_PCM,
 158 };
 159
 160 DECLARE_USB_AS_FORMAT_TYPE_I_DISCRETE_DESC(1);
 161
 162 static struct usb_as_formate_type_i_discrete_descriptor_1 as_type_i_desc = {
 163         .bLength =              USB_AS_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
 164         .bDescriptorType =      USB_DT_CS_INTERFACE,
 165         .bDescriptorSubtype =   FORMAT_TYPE,
 166         .bFormatType =          USB_AS_FORMAT_TYPE_I,
 167         .bSubframeSize =        2,
 168         .bBitResolution =       16,
 169         .bSamFreqType =         1,
 170 };
 171
 172 /* Standard ISO OUT Endpoint Descriptor */
 173 static struct usb_endpoint_descriptor as_out_ep_desc __initdata = {
 174         .bLength =              USB_DT_ENDPOINT_AUDIO_SIZE,
 175         .bDescriptorType =      USB_DT_ENDPOINT,
 176         .bEndpointAddress =     USB_DIR_OUT,
 177         .bmAttributes =         USB_AS_ENDPOINT_ADAPTIVE
 178                                 | USB_ENDPOINT_XFER_ISOC,
 179         .wMaxPacketSize =       __constant_cpu_to_le16(OUT_EP_MAX_PACKET_SIZE),
 180         .bInterval =            4,
 181 };
 182
 183 /* Class-specific AS ISO OUT Endpoint Descriptor */
 184 static struct usb_as_iso_endpoint_descriptor as_iso_out_desc __initdata = {
 185         .bLength =              USB_AS_ISO_ENDPOINT_DESC_SIZE,
 186         .bDescriptorType =      USB_DT_CS_ENDPOINT,
 187         .bDescriptorSubtype =   EP_GENERAL,
 188         .bmAttributes =         1,
 189         .bLockDelayUnits =      1,
 190         .wLockDelay =           __constant_cpu_to_le16(1),
 191 };
 192
 193 static struct usb_descriptor_header *f_audio_desc[] __initdata = {
 194         (struct usb_descriptor_header *)&ac_interface_desc,
 195         (struct usb_descriptor_header *)&ac_header_desc,
 196
 197         (struct usb_descriptor_header *)&input_terminal_desc,
 198         (struct usb_descriptor_header *)&output_terminal_desc,
 199         (struct usb_descriptor_header *)&feature_unit_desc,
 200
 201         (struct usb_descriptor_header *)&as_interface_alt_0_desc,
 202         (struct usb_descriptor_header *)&as_interface_alt_1_desc,
 203         (struct usb_descriptor_header *)&as_header_desc,
 204
 205         (struct usb_descriptor_header *)&as_type_i_desc,
 206
 207         (struct usb_descriptor_header *)&as_out_ep_desc,
 208         (struct usb_descriptor_header *)&as_iso_out_desc,
 209         NULL,
 210 };
 211
 212 /* string IDs are assigned dynamically */
 213
 214 #define STRING_MANUFACTURER_IDX         0
 215 #define STRING_PRODUCT_IDX              1
 216
 217 static char manufacturer[50];
 218
 219 static struct usb_string strings_dev[] = {
 220         [STRING_MANUFACTURER_IDX].s = manufacturer,
 221         [STRING_PRODUCT_IDX].s = DRIVER_DESC,
 222         {  } /* end of list */
 223 };
 224
 225 static struct usb_gadget_strings stringtab_dev = {
 226         .language       = 0x0409,       /* en-us */
 227         .strings        = strings_dev,
 228 };
 229
 230 static struct usb_gadget_strings *audio_strings[] = {
 231         &stringtab_dev,
 232         NULL,
 233 };
 234
 235 /*
 236  * This function is an ALSA sound card following USB Audio Class Spec 1.0.
 237  */
 238
 239 /*-------------------------------------------------------------------------*/
 240 struct f_audio_buf {
 241         u8 *buf;
 242         int actual;
 243         struct list_head list;
 244 };
 245
 246 static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
 247 {
 248         struct f_audio_buf *copy_buf;
 249
 250         copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
 251         if (!copy_buf)
 252                 return (struct f_audio_buf *)-ENOMEM;
 253
 254         copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
 255         if (!copy_buf->buf) {
 256                 kfree(copy_buf);
 257                 return (struct f_audio_buf *)-ENOMEM;
 258         }
 259
 260         return copy_buf;
 261 }
 262
 263 static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
 264 {
 265         kfree(audio_buf->buf);
 266         kfree(audio_buf);
 267 }
 268 /*-------------------------------------------------------------------------*/
 269
 270 struct f_audio {
 271         struct gaudio                   card;
 272
 273         /* endpoints handle full and/or high speeds */
 274         struct usb_ep                   *out_ep;
 275         struct usb_endpoint_descriptor  *out_desc;
 276
 277         spinlock_t                      lock;
 278         struct f_audio_buf *copy_buf;
 279         struct work_struct playback_work;
 280         struct list_head play_queue;
 281
 282         /* Control Set command */
 283         struct list_head cs;
 284         u8 set_cmd;
 285         struct usb_audio_control *set_con;
 286 };
 287
 288 static inline struct f_audio *func_to_audio(struct usb_function *f)
 289 {
 290         return container_of(f, struct f_audio, card.func);
 291 }
 292
 293 /*-------------------------------------------------------------------------*/
 294
 295 static void f_audio_playback_work(struct work_struct *data)
 296 {
 297         struct f_audio *audio = container_of(data, struct f_audio,
 298                                         playback_work);
 299         struct f_audio_buf *play_buf;
 300
 301         spin_lock_irq(&audio->lock);
 302         if (list_empty(&audio->play_queue)) {
 303                 spin_unlock_irq(&audio->lock);
 304                 return;
 305         }
 306         play_buf = list_first_entry(&audio->play_queue,
 307                         struct f_audio_buf, list);
 308         list_del(&play_buf->list);
 309         spin_unlock_irq(&audio->lock);
 310
 311         u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
 312         f_audio_buffer_free(play_buf);
 313
 314         return;
 315 }
 316
 317 static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
 318 {
 319         struct f_audio *audio = req->context;
 320         struct usb_composite_dev *cdev = audio->card.func.config->cdev;
 321         struct f_audio_buf *copy_buf = audio->copy_buf;
 322         int err;
 323
 324         if (!copy_buf)
 325                 return -EINVAL;
 326
 327         /* Copy buffer is full, add it to the play_queue */
 328         if (audio_buf_size - copy_buf->actual < req->actual) {
 329                 list_add_tail(&copy_buf->list, &audio->play_queue);
 330                 schedule_work(&audio->playback_work);
 331                 copy_buf = f_audio_buffer_alloc(audio_buf_size);
 332                 if (copy_buf < 0)
 333                         return -ENOMEM;
 334         }
 335
 336         memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
 337         copy_buf->actual += req->actual;
 338         audio->copy_buf = copy_buf;
 339
 340         err = usb_ep_queue(ep, req, GFP_ATOMIC);
 341         if (err)
 342                 ERROR(cdev, "%s queue req: %d\n", ep->name, err);
 343
 344         return 0;
 345
 346 }
 347
 348 static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
 349 {
 350         struct f_audio *audio = req->context;
 351         int status = req->status;
 352         u32 data = 0;
 353         struct usb_ep *out_ep = audio->out_ep;
 354
 355         switch (status) {
 356
 357         case 0:                         /* normal completion? */
 358                 if (ep == out_ep)
 359                         f_audio_out_ep_complete(ep, req);
 360                 else if (audio->set_con) {
 361                         memcpy(&data, req->buf, req->length);
 362                         audio->set_con->set(audio->set_con, audio->set_cmd,
 363                                         le16_to_cpu(data));
 364                         audio->set_con = NULL;
 365                 }
 366                 break;
 367         default:
 368                 break;
 369         }
 370 }
 371
 372 static int audio_set_intf_req(struct usb_function *f,
 373                 const struct usb_ctrlrequest *ctrl)
 374 {
 375         struct f_audio          *audio = func_to_audio(f);
 376         struct usb_composite_dev *cdev = f->config->cdev;
 377         struct usb_request      *req = cdev->req;
 378         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 379         u16                     len = le16_to_cpu(ctrl->wLength);
 380         u16                     w_value = le16_to_cpu(ctrl->wValue);
 381         u8                      con_sel = (w_value >> 8) & 0xFF;
 382         u8                      cmd = (ctrl->bRequest & 0x0F);
 383         struct usb_audio_control_selector *cs;
 384         struct usb_audio_control *con;
 385
 386         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 387                         ctrl->bRequest, w_value, len, id);
 388
 389         list_for_each_entry(cs, &audio->cs, list) {
 390                 if (cs->id == id) {
 391                         list_for_each_entry(con, &cs->control, list) {
 392                                 if (con->type == con_sel) {
 393                                         audio->set_con = con;
 394                                         break;
 395                                 }
 396                         }
 397                         break;
 398                 }
 399         }
 400
 401         audio->set_cmd = cmd;
 402         req->context = audio;
 403         req->complete = f_audio_complete;
 404
 405         return len;
 406 }
 407
 408 static int audio_get_intf_req(struct usb_function *f,
 409                 const struct usb_ctrlrequest *ctrl)
 410 {
 411         struct f_audio          *audio = func_to_audio(f);
 412         struct usb_composite_dev *cdev = f->config->cdev;
 413         struct usb_request      *req = cdev->req;
 414         int                     value = -EOPNOTSUPP;
 415         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 416         u16                     len = le16_to_cpu(ctrl->wLength);
 417         u16                     w_value = le16_to_cpu(ctrl->wValue);
 418         u8                      con_sel = (w_value >> 8) & 0xFF;
 419         u8                      cmd = (ctrl->bRequest & 0x0F);
 420         struct usb_audio_control_selector *cs;
 421         struct usb_audio_control *con;
 422
 423         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 424                         ctrl->bRequest, w_value, len, id);
 425
 426         list_for_each_entry(cs, &audio->cs, list) {
 427                 if (cs->id == id) {
 428                         list_for_each_entry(con, &cs->control, list) {
 429                                 if (con->type == con_sel && con->get) {
 430                                         value = con->get(con, cmd);
 431                                         break;
 432                                 }
 433                         }
 434                         break;
 435                 }
 436         }
 437
 438         req->context = audio;
 439         req->complete = f_audio_complete;
 440         memcpy(req->buf, &value, len);
 441
 442         return len;
 443 }
 444
 445 static int
 446 f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 447 {
 448         struct usb_composite_dev *cdev = f->config->cdev;
 449         struct usb_request      *req = cdev->req;
 450         int                     value = -EOPNOTSUPP;
 451         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 452         u16                     w_value = le16_to_cpu(ctrl->wValue);
 453         u16                     w_length = le16_to_cpu(ctrl->wLength);
 454
 455         /* composite driver infrastructure handles everything except
 456          * Audio class messages; interface activation uses set_alt().
 457          */
 458         switch (ctrl->bRequestType) {
 459         case USB_AUDIO_SET_INTF:
 460                 value = audio_set_intf_req(f, ctrl);
 461                 break;
 462
 463         case USB_AUDIO_GET_INTF:
 464                 value = audio_get_intf_req(f, ctrl);
 465                 break;
 466
 467         default:
 468                 ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 469                         ctrl->bRequestType, ctrl->bRequest,
 470                         w_value, w_index, w_length);
 471         }
 472
 473         /* respond with data transfer or status phase? */
 474         if (value >= 0) {
 475                 DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
 476                         ctrl->bRequestType, ctrl->bRequest,
 477                         w_value, w_index, w_length);
 478                 req->zero = 0;
 479                 req->length = value;
 480                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 481                 if (value < 0)
 482                         ERROR(cdev, "audio response on err %d\n", value);
 483         }
 484
 485         /* device either stalls (value < 0) or reports success */
 486         return value;
 487 }
 488
 489 static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 490 {
 491         struct f_audio          *audio = func_to_audio(f);
 492         struct usb_composite_dev *cdev = f->config->cdev;
 493         struct usb_ep *out_ep = audio->out_ep;
 494         struct usb_request *req;
 495         int i = 0, err = 0;
 496
 497         DBG(cdev, "intf %d, alt %d\n", intf, alt);
 498
 499         if (intf == 1) {
 500                 if (alt == 1) {
 501                         usb_ep_enable(out_ep, audio->out_desc);
 502                         out_ep->driver_data = audio;
 503                         audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
 504
 505                         /*
 506                          * allocate a bunch of read buffers
 507                          * and queue them all at once.
 508                          */
 509                         for (i = 0; i < req_count && err == 0; i++) {
 510                                 req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
 511                                 if (req) {
 512                                         req->buf = kzalloc(req_buf_size,
 513                                                         GFP_ATOMIC);
 514                                         if (req->buf) {
 515                                                 req->length = req_buf_size;
 516                                                 req->context = audio;
 517                                                 req->complete =
 518                                                         f_audio_complete;
 519                                                 err = usb_ep_queue(out_ep,
 520                                                         req, GFP_ATOMIC);
 521                                                 if (err)
 522                                                         ERROR(cdev,
 523                                                         "%s queue req: %d\n",
 524                                                         out_ep->name, err);
 525                                         } else
 526                                                 err = -ENOMEM;
 527                                 } else
 528                                         err = -ENOMEM;
 529                         }
 530
 531                 } else {
 532                         struct f_audio_buf *copy_buf = audio->copy_buf;
 533                         if (copy_buf) {
 534                                 list_add_tail(&copy_buf->list,
 535                                                 &audio->play_queue);
 536                                 schedule_work(&audio->playback_work);
 537                         }
 538                 }
 539         }
 540
 541         return err;
 542 }
 543
 544 static void f_audio_disable(struct usb_function *f)
 545 {
 546         return;
 547 }
 548
 549 /*-------------------------------------------------------------------------*/
 550
 551 static void f_audio_build_desc(struct f_audio *audio)
 552 {
 553         struct gaudio *card = &audio->card;
 554         u8 *sam_freq;
 555         int rate;
 556
 557         /* Set channel numbers */
 558         input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
 559         as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
 560
 561         /* Set sample rates */
 562         rate = u_audio_get_playback_rate(card);
 563         sam_freq = as_type_i_desc.tSamFreq[0];
 564         memcpy(sam_freq, &rate, 3);
 565
 566         /* Todo: Set Sample bits and other parameters */
 567
 568         return;
 569 }
 570
 571 /* audio function driver setup/binding */
 572 static int __init
 573 f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 574 {
 575         struct usb_composite_dev *cdev = c->cdev;
 576         struct f_audio          *audio = func_to_audio(f);
 577         int                     status;
 578         struct usb_ep           *ep;
 579
 580         f_audio_build_desc(audio);
 581
 582         /* allocate instance-specific interface IDs, and patch descriptors */
 583         status = usb_interface_id(c, f);
 584         if (status < 0)
 585                 goto fail;
 586         ac_interface_desc.bInterfaceNumber = status;
 587
 588         status = usb_interface_id(c, f);
 589         if (status < 0)
 590                 goto fail;
 591         as_interface_alt_0_desc.bInterfaceNumber = status;
 592         as_interface_alt_1_desc.bInterfaceNumber = status;
 593
 594         status = -ENODEV;
 595
 596         /* allocate instance-specific endpoints */
 597         ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
 598         if (!ep)
 599                 goto fail;
 600         audio->out_ep = ep;
 601         ep->driver_data = cdev; /* claim */
 602
 603         status = -ENOMEM;
 604
 605         /* supcard all relevant hardware speeds... we expect that when
 606          * hardware is dual speed, all bulk-capable endpoints work at
 607          * both speeds
 608          */
 609
 610         /* copy descriptors, and track endpoint copies */
 611         if (gadget_is_dualspeed(c->cdev->gadget)) {
 612                 c->highspeed = true;
 613                 f->hs_descriptors = usb_copy_descriptors(f_audio_desc);
 614         } else
 615                 f->descriptors = usb_copy_descriptors(f_audio_desc);
 616
 617         return 0;
 618
 619 fail:
 620
 621         return status;
 622 }
 623
 624 static void
 625 f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 626 {
 627         struct f_audio          *audio = func_to_audio(f);
 628
 629         usb_free_descriptors(f->descriptors);
 630         kfree(audio);
 631 }
 632
 633 /*-------------------------------------------------------------------------*/
 634
 635 /* Todo: add more control selecotor dynamically */
 636 int __init control_selector_init(struct f_audio *audio)
 637 {
 638         INIT_LIST_HEAD(&audio->cs);
 639         list_add(&feature_unit.list, &audio->cs);
 640
 641         INIT_LIST_HEAD(&feature_unit.control);
 642         list_add(&mute_control.list, &feature_unit.control);
 643         list_add(&volume_control.list, &feature_unit.control);
 644
 645         volume_control.data[_CUR] = 0xffc0;
 646         volume_control.data[_MIN] = 0xe3a0;
 647         volume_control.data[_MAX] = 0xfff0;
 648         volume_control.data[_RES] = 0x0030;
 649
 650         return 0;
 651 }
 652
 653 /**
 654  * audio_bind_config - add USB audio fucntion to a configuration
 655  * @c: the configuration to supcard the USB audio function
 656  * Context: single threaded during gadget setup
 657  *
 658  * Returns zero on success, else negative errno.
 659  */
 660 int __init audio_bind_config(struct usb_configuration *c)
 661 {
 662         struct f_audio *audio;
 663         int status;
 664
 665         /* allocate and initialize one new instance */
 666         audio = kzalloc(sizeof *audio, GFP_KERNEL);
 667         if (!audio)
 668                 return -ENOMEM;
 669
 670         audio->card.func.name = "g_audio";
 671         audio->card.gadget = c->cdev->gadget;
 672
 673         INIT_LIST_HEAD(&audio->play_queue);
 674         spin_lock_init(&audio->lock);
 675
 676         /* set up ASLA audio devices */
 677         status = gaudio_setup(&audio->card);
 678         if (status < 0)
 679                 goto setup_fail;
 680
 681         audio->card.func.strings = audio_strings;
 682         audio->card.func.bind = f_audio_bind;
 683         audio->card.func.unbind = f_audio_unbind;
 684         audio->card.func.set_alt = f_audio_set_alt;
 685         audio->card.func.setup = f_audio_setup;
 686         audio->card.func.disable = f_audio_disable;
 687         audio->out_desc = &as_out_ep_desc;
 688
 689         control_selector_init(audio);
 690
 691         INIT_WORK(&audio->playback_work, f_audio_playback_work);
 692
 693         status = usb_add_function(c, &audio->card.func);
 694         if (status)
 695                 goto add_fail;
 696
 697         INFO(c->cdev, "audio_buf_size %d, req_buf_size %d, req_count %d\n",
 698                 audio_buf_size, req_buf_size, req_count);
 699
 700         return status;
 701
 702 add_fail:
 703         gaudio_cleanup(&audio->card);
 704 setup_fail:
 705         kfree(audio);
 706         return status;
 707 }