drivers/usb/gadget/f_uac1.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/slab.h>
  13 #include <linux/kernel.h>
  14 #include <linux/device.h>
  15 #include <linux/atomic.h>
  16
  17 #include "u_uac1.h"
  18
  19 #define OUT_EP_MAX_PACKET_SIZE  200
  20 static int req_buf_size = OUT_EP_MAX_PACKET_SIZE;
  21 module_param(req_buf_size, int, S_IRUGO);
  22 MODULE_PARM_DESC(req_buf_size, "ISO OUT endpoint request buffer size");
  23
  24 static int req_count = 256;
  25 module_param(req_count, int, S_IRUGO);
  26 MODULE_PARM_DESC(req_count, "ISO OUT endpoint request count");
  27
  28 static int audio_buf_size = 48000;
  29 module_param(audio_buf_size, int, S_IRUGO);
  30 MODULE_PARM_DESC(audio_buf_size, "Audio buffer size");
  31
  32 static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
  33 static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
  34
  35 /*
  36  * DESCRIPTORS ... most are static, but strings and full
  37  * configuration descriptors are built on demand.
  38  */
  39
  40 /*
  41  * We have two interfaces- AudioControl and AudioStreaming
  42  * TODO: only supcard playback currently
  43  */
  44 #define F_AUDIO_AC_INTERFACE    0
  45 #define F_AUDIO_AS_INTERFACE    1
  46 #define F_AUDIO_NUM_INTERFACES  2
  47
  48 /* B.3.1  Standard AC Interface Descriptor */
  49 static struct usb_interface_descriptor ac_interface_desc __initdata = {
  50         .bLength =              USB_DT_INTERFACE_SIZE,
  51         .bDescriptorType =      USB_DT_INTERFACE,
  52         .bNumEndpoints =        0,
  53         .bInterfaceClass =      USB_CLASS_AUDIO,
  54         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOCONTROL,
  55 };
  56
  57 DECLARE_UAC_AC_HEADER_DESCRIPTOR(2);
  58
  59 #define UAC_DT_AC_HEADER_LENGTH UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
  60 /* 1 input terminal, 1 output terminal and 1 feature unit */
  61 #define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
  62         + UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
  63 /* B.3.2  Class-Specific AC Interface Descriptor */
  64 static struct uac1_ac_header_descriptor_2 ac_header_desc = {
  65         .bLength =              UAC_DT_AC_HEADER_LENGTH,
  66         .bDescriptorType =      USB_DT_CS_INTERFACE,
  67         .bDescriptorSubtype =   UAC_HEADER,
  68         .bcdADC =               __constant_cpu_to_le16(0x0100),
  69         .wTotalLength =         __constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH),
  70         .bInCollection =        F_AUDIO_NUM_INTERFACES,
  71         .baInterfaceNr = {
  72                 [0] =           F_AUDIO_AC_INTERFACE,
  73                 [1] =           F_AUDIO_AS_INTERFACE,
  74         }
  75 };
  76
  77 #define INPUT_TERMINAL_ID       1
  78 static struct uac_input_terminal_descriptor input_terminal_desc = {
  79         .bLength =              UAC_DT_INPUT_TERMINAL_SIZE,
  80         .bDescriptorType =      USB_DT_CS_INTERFACE,
  81         .bDescriptorSubtype =   UAC_INPUT_TERMINAL,
  82         .bTerminalID =          INPUT_TERMINAL_ID,
  83         .wTerminalType =        UAC_TERMINAL_STREAMING,
  84         .bAssocTerminal =       0,
  85         .wChannelConfig =       0x3,
  86 };
  87
  88 DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
  89
  90 #define FEATURE_UNIT_ID         2
  91 static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
  92         .bLength                = UAC_DT_FEATURE_UNIT_SIZE(0),
  93         .bDescriptorType        = USB_DT_CS_INTERFACE,
  94         .bDescriptorSubtype     = UAC_FEATURE_UNIT,
  95         .bUnitID                = FEATURE_UNIT_ID,
  96         .bSourceID              = INPUT_TERMINAL_ID,
  97         .bControlSize           = 2,
  98         .bmaControls[0]         = (UAC_FU_MUTE | UAC_FU_VOLUME),
  99 };
 100
 101 static struct usb_audio_control mute_control = {
 102         .list = LIST_HEAD_INIT(mute_control.list),
 103         .name = "Mute Control",
 104         .type = UAC_FU_MUTE,
 105         /* Todo: add real Mute control code */
 106         .set = generic_set_cmd,
 107         .get = generic_get_cmd,
 108 };
 109
 110 static struct usb_audio_control volume_control = {
 111         .list = LIST_HEAD_INIT(volume_control.list),
 112         .name = "Volume Control",
 113         .type = UAC_FU_VOLUME,
 114         /* Todo: add real Volume control code */
 115         .set = generic_set_cmd,
 116         .get = generic_get_cmd,
 117 };
 118
 119 static struct usb_audio_control_selector feature_unit = {
 120         .list = LIST_HEAD_INIT(feature_unit.list),
 121         .id = FEATURE_UNIT_ID,
 122         .name = "Mute & Volume Control",
 123         .type = UAC_FEATURE_UNIT,
 124         .desc = (struct usb_descriptor_header *)&feature_unit_desc,
 125 };
 126
 127 #define OUTPUT_TERMINAL_ID      3
 128 static struct uac1_output_terminal_descriptor output_terminal_desc = {
 129         .bLength                = UAC_DT_OUTPUT_TERMINAL_SIZE,
 130         .bDescriptorType        = USB_DT_CS_INTERFACE,
 131         .bDescriptorSubtype     = UAC_OUTPUT_TERMINAL,
 132         .bTerminalID            = OUTPUT_TERMINAL_ID,
 133         .wTerminalType          = UAC_OUTPUT_TERMINAL_SPEAKER,
 134         .bAssocTerminal         = FEATURE_UNIT_ID,
 135         .bSourceID              = FEATURE_UNIT_ID,
 136 };
 137
 138 /* B.4.1  Standard AS Interface Descriptor */
 139 static struct usb_interface_descriptor as_interface_alt_0_desc = {
 140         .bLength =              USB_DT_INTERFACE_SIZE,
 141         .bDescriptorType =      USB_DT_INTERFACE,
 142         .bAlternateSetting =    0,
 143         .bNumEndpoints =        0,
 144         .bInterfaceClass =      USB_CLASS_AUDIO,
 145         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 146 };
 147
 148 static struct usb_interface_descriptor as_interface_alt_1_desc = {
 149         .bLength =              USB_DT_INTERFACE_SIZE,
 150         .bDescriptorType =      USB_DT_INTERFACE,
 151         .bAlternateSetting =    1,
 152         .bNumEndpoints =        1,
 153         .bInterfaceClass =      USB_CLASS_AUDIO,
 154         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 155 };
 156
 157 /* B.4.2  Class-Specific AS Interface Descriptor */
 158 static struct uac1_as_header_descriptor as_header_desc = {
 159         .bLength =              UAC_DT_AS_HEADER_SIZE,
 160         .bDescriptorType =      USB_DT_CS_INTERFACE,
 161         .bDescriptorSubtype =   UAC_AS_GENERAL,
 162         .bTerminalLink =        INPUT_TERMINAL_ID,
 163         .bDelay =               1,
 164         .wFormatTag =           UAC_FORMAT_TYPE_I_PCM,
 165 };
 166
 167 DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
 168
 169 static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
 170         .bLength =              UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
 171         .bDescriptorType =      USB_DT_CS_INTERFACE,
 172         .bDescriptorSubtype =   UAC_FORMAT_TYPE,
 173         .bFormatType =          UAC_FORMAT_TYPE_I,
 174         .bSubframeSize =        2,
 175         .bBitResolution =       16,
 176         .bSamFreqType =         1,
 177 };
 178
 179 /* Standard ISO OUT Endpoint Descriptor */
 180 static struct usb_endpoint_descriptor as_out_ep_desc  = {
 181         .bLength =              USB_DT_ENDPOINT_AUDIO_SIZE,
 182         .bDescriptorType =      USB_DT_ENDPOINT,
 183         .bEndpointAddress =     USB_DIR_OUT,
 184         .bmAttributes =         USB_ENDPOINT_SYNC_ADAPTIVE
 185                                 | USB_ENDPOINT_XFER_ISOC,
 186         .wMaxPacketSize =       __constant_cpu_to_le16(OUT_EP_MAX_PACKET_SIZE),
 187         .bInterval =            4,
 188 };
 189
 190 /* Class-specific AS ISO OUT Endpoint Descriptor */
 191 static struct uac_iso_endpoint_descriptor as_iso_out_desc __initdata = {
 192         .bLength =              UAC_ISO_ENDPOINT_DESC_SIZE,
 193         .bDescriptorType =      USB_DT_CS_ENDPOINT,
 194         .bDescriptorSubtype =   UAC_EP_GENERAL,
 195         .bmAttributes =         1,
 196         .bLockDelayUnits =      1,
 197         .wLockDelay =           __constant_cpu_to_le16(1),
 198 };
 199
 200 static struct usb_descriptor_header *f_audio_desc[] __initdata = {
 201         (struct usb_descriptor_header *)&ac_interface_desc,
 202         (struct usb_descriptor_header *)&ac_header_desc,
 203
 204         (struct usb_descriptor_header *)&input_terminal_desc,
 205         (struct usb_descriptor_header *)&output_terminal_desc,
 206         (struct usb_descriptor_header *)&feature_unit_desc,
 207
 208         (struct usb_descriptor_header *)&as_interface_alt_0_desc,
 209         (struct usb_descriptor_header *)&as_interface_alt_1_desc,
 210         (struct usb_descriptor_header *)&as_header_desc,
 211
 212         (struct usb_descriptor_header *)&as_type_i_desc,
 213
 214         (struct usb_descriptor_header *)&as_out_ep_desc,
 215         (struct usb_descriptor_header *)&as_iso_out_desc,
 216         NULL,
 217 };
 218
 219 /*
 220  * This function is an ALSA sound card following USB Audio Class Spec 1.0.
 221  */
 222
 223 /*-------------------------------------------------------------------------*/
 224 struct f_audio_buf {
 225         u8 *buf;
 226         int actual;
 227         struct list_head list;
 228 };
 229
 230 static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
 231 {
 232         struct f_audio_buf *copy_buf;
 233
 234         copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
 235         if (!copy_buf)
 236                 return ERR_PTR(-ENOMEM);
 237
 238         copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
 239         if (!copy_buf->buf) {
 240                 kfree(copy_buf);
 241                 return ERR_PTR(-ENOMEM);
 242         }
 243
 244         return copy_buf;
 245 }
 246
 247 static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
 248 {
 249         kfree(audio_buf->buf);
 250         kfree(audio_buf);
 251 }
 252 /*-------------------------------------------------------------------------*/
 253
 254 struct f_audio {
 255         struct gaudio                   card;
 256
 257         /* endpoints handle full and/or high speeds */
 258         struct usb_ep                   *out_ep;
 259
 260         spinlock_t                      lock;
 261         struct f_audio_buf *copy_buf;
 262         struct work_struct playback_work;
 263         struct list_head play_queue;
 264
 265         /* Control Set command */
 266         struct list_head cs;
 267         u8 set_cmd;
 268         struct usb_audio_control *set_con;
 269 };
 270
 271 static inline struct f_audio *func_to_audio(struct usb_function *f)
 272 {
 273         return container_of(f, struct f_audio, card.func);
 274 }
 275
 276 /*-------------------------------------------------------------------------*/
 277
 278 static void f_audio_playback_work(struct work_struct *data)
 279 {
 280         struct f_audio *audio = container_of(data, struct f_audio,
 281                                         playback_work);
 282         struct f_audio_buf *play_buf;
 283
 284         spin_lock_irq(&audio->lock);
 285         if (list_empty(&audio->play_queue)) {
 286                 spin_unlock_irq(&audio->lock);
 287                 return;
 288         }
 289         play_buf = list_first_entry(&audio->play_queue,
 290                         struct f_audio_buf, list);
 291         list_del(&play_buf->list);
 292         spin_unlock_irq(&audio->lock);
 293
 294         u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
 295         f_audio_buffer_free(play_buf);
 296 }
 297
 298 static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
 299 {
 300         struct f_audio *audio = req->context;
 301         struct usb_composite_dev *cdev = audio->card.func.config->cdev;
 302         struct f_audio_buf *copy_buf = audio->copy_buf;
 303         int err;
 304
 305         if (!copy_buf)
 306                 return -EINVAL;
 307
 308         /* Copy buffer is full, add it to the play_queue */
 309         if (audio_buf_size - copy_buf->actual < req->actual) {
 310                 list_add_tail(&copy_buf->list, &audio->play_queue);
 311                 schedule_work(&audio->playback_work);
 312                 copy_buf = f_audio_buffer_alloc(audio_buf_size);
 313                 if (IS_ERR(copy_buf))
 314                         return -ENOMEM;
 315         }
 316
 317         memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
 318         copy_buf->actual += req->actual;
 319         audio->copy_buf = copy_buf;
 320
 321         err = usb_ep_queue(ep, req, GFP_ATOMIC);
 322         if (err)
 323                 ERROR(cdev, "%s queue req: %d\n", ep->name, err);
 324
 325         return 0;
 326
 327 }
 328
 329 static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
 330 {
 331         struct f_audio *audio = req->context;
 332         int status = req->status;
 333         u32 data = 0;
 334         struct usb_ep *out_ep = audio->out_ep;
 335
 336         switch (status) {
 337
 338         case 0:                         /* normal completion? */
 339                 if (ep == out_ep)
 340                         f_audio_out_ep_complete(ep, req);
 341                 else if (audio->set_con) {
 342                         memcpy(&data, req->buf, req->length);
 343                         audio->set_con->set(audio->set_con, audio->set_cmd,
 344                                         le16_to_cpu(data));
 345                         audio->set_con = NULL;
 346                 }
 347                 break;
 348         default:
 349                 break;
 350         }
 351 }
 352
 353 static int audio_set_intf_req(struct usb_function *f,
 354                 const struct usb_ctrlrequest *ctrl)
 355 {
 356         struct f_audio          *audio = func_to_audio(f);
 357         struct usb_composite_dev *cdev = f->config->cdev;
 358         struct usb_request      *req = cdev->req;
 359         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 360         u16                     len = le16_to_cpu(ctrl->wLength);
 361         u16                     w_value = le16_to_cpu(ctrl->wValue);
 362         u8                      con_sel = (w_value >> 8) & 0xFF;
 363         u8                      cmd = (ctrl->bRequest & 0x0F);
 364         struct usb_audio_control_selector *cs;
 365         struct usb_audio_control *con;
 366
 367         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 368                         ctrl->bRequest, w_value, len, id);
 369
 370         list_for_each_entry(cs, &audio->cs, list) {
 371                 if (cs->id == id) {
 372                         list_for_each_entry(con, &cs->control, list) {
 373                                 if (con->type == con_sel) {
 374                                         audio->set_con = con;
 375                                         break;
 376                                 }
 377                         }
 378                         break;
 379                 }
 380         }
 381
 382         audio->set_cmd = cmd;
 383         req->context = audio;
 384         req->complete = f_audio_complete;
 385
 386         return len;
 387 }
 388
 389 static int audio_get_intf_req(struct usb_function *f,
 390                 const struct usb_ctrlrequest *ctrl)
 391 {
 392         struct f_audio          *audio = func_to_audio(f);
 393         struct usb_composite_dev *cdev = f->config->cdev;
 394         struct usb_request      *req = cdev->req;
 395         int                     value = -EOPNOTSUPP;
 396         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 397         u16                     len = le16_to_cpu(ctrl->wLength);
 398         u16                     w_value = le16_to_cpu(ctrl->wValue);
 399         u8                      con_sel = (w_value >> 8) & 0xFF;
 400         u8                      cmd = (ctrl->bRequest & 0x0F);
 401         struct usb_audio_control_selector *cs;
 402         struct usb_audio_control *con;
 403
 404         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 405                         ctrl->bRequest, w_value, len, id);
 406
 407         list_for_each_entry(cs, &audio->cs, list) {
 408                 if (cs->id == id) {
 409                         list_for_each_entry(con, &cs->control, list) {
 410                                 if (con->type == con_sel && con->get) {
 411                                         value = con->get(con, cmd);
 412                                         break;
 413                                 }
 414                         }
 415                         break;
 416                 }
 417         }
 418
 419         req->context = audio;
 420         req->complete = f_audio_complete;
 421         memcpy(req->buf, &value, len);
 422
 423         return len;
 424 }
 425
 426 static int audio_set_endpoint_req(struct usb_function *f,
 427                 const struct usb_ctrlrequest *ctrl)
 428 {
 429         struct usb_composite_dev *cdev = f->config->cdev;
 430         int                     value = -EOPNOTSUPP;
 431         u16                     ep = le16_to_cpu(ctrl->wIndex);
 432         u16                     len = le16_to_cpu(ctrl->wLength);
 433         u16                     w_value = le16_to_cpu(ctrl->wValue);
 434
 435         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 436                         ctrl->bRequest, w_value, len, ep);
 437
 438         switch (ctrl->bRequest) {
 439         case UAC_SET_CUR:
 440                 value = len;
 441                 break;
 442
 443         case UAC_SET_MIN:
 444                 break;
 445
 446         case UAC_SET_MAX:
 447                 break;
 448
 449         case UAC_SET_RES:
 450                 break;
 451
 452         case UAC_SET_MEM:
 453                 break;
 454
 455         default:
 456                 break;
 457         }
 458
 459         return value;
 460 }
 461
 462 static int audio_get_endpoint_req(struct usb_function *f,
 463                 const struct usb_ctrlrequest *ctrl)
 464 {
 465         struct usb_composite_dev *cdev = f->config->cdev;
 466         int value = -EOPNOTSUPP;
 467         u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 468         u16 len = le16_to_cpu(ctrl->wLength);
 469         u16 w_value = le16_to_cpu(ctrl->wValue);
 470
 471         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 472                         ctrl->bRequest, w_value, len, ep);
 473
 474         switch (ctrl->bRequest) {
 475         case UAC_GET_CUR:
 476         case UAC_GET_MIN:
 477         case UAC_GET_MAX:
 478         case UAC_GET_RES:
 479                 value = len;
 480                 break;
 481         case UAC_GET_MEM:
 482                 break;
 483         default:
 484                 break;
 485         }
 486
 487         return value;
 488 }
 489
 490 static int
 491 f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 492 {
 493         struct usb_composite_dev *cdev = f->config->cdev;
 494         struct usb_request      *req = cdev->req;
 495         int                     value = -EOPNOTSUPP;
 496         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 497         u16                     w_value = le16_to_cpu(ctrl->wValue);
 498         u16                     w_length = le16_to_cpu(ctrl->wLength);
 499
 500         /* composite driver infrastructure handles everything; interface
 501          * activation uses set_alt().
 502          */
 503         switch (ctrl->bRequestType) {
 504         case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 505                 value = audio_set_intf_req(f, ctrl);
 506                 break;
 507
 508         case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 509                 value = audio_get_intf_req(f, ctrl);
 510                 break;
 511
 512         case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 513                 value = audio_set_endpoint_req(f, ctrl);
 514                 break;
 515
 516         case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 517                 value = audio_get_endpoint_req(f, ctrl);
 518                 break;
 519
 520         default:
 521                 ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 522                         ctrl->bRequestType, ctrl->bRequest,
 523                         w_value, w_index, w_length);
 524         }
 525
 526         /* respond with data transfer or status phase? */
 527         if (value >= 0) {
 528                 DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
 529                         ctrl->bRequestType, ctrl->bRequest,
 530                         w_value, w_index, w_length);
 531                 req->zero = 0;
 532                 req->length = value;
 533                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 534                 if (value < 0)
 535                         ERROR(cdev, "audio response on err %d\n", value);
 536         }
 537
 538         /* device either stalls (value < 0) or reports success */
 539         return value;
 540 }
 541
 542 static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 543 {
 544         struct f_audio          *audio = func_to_audio(f);
 545         struct usb_composite_dev *cdev = f->config->cdev;
 546         struct usb_ep *out_ep = audio->out_ep;
 547         struct usb_request *req;
 548         int i = 0, err = 0;
 549
 550         DBG(cdev, "intf %d, alt %d\n", intf, alt);
 551
 552         if (intf == 1) {
 553                 if (alt == 1) {
 554                         usb_ep_enable(out_ep);
 555                         out_ep->driver_data = audio;
 556                         audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
 557                         if (IS_ERR(audio->copy_buf))
 558                                 return -ENOMEM;
 559
 560                         /*
 561                          * allocate a bunch of read buffers
 562                          * and queue them all at once.
 563                          */
 564                         for (i = 0; i < req_count && err == 0; i++) {
 565                                 req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
 566                                 if (req) {
 567                                         req->buf = kzalloc(req_buf_size,
 568                                                         GFP_ATOMIC);
 569                                         if (req->buf) {
 570                                                 req->length = req_buf_size;
 571                                                 req->context = audio;
 572                                                 req->complete =
 573                                                         f_audio_complete;
 574                                                 err = usb_ep_queue(out_ep,
 575                                                         req, GFP_ATOMIC);
 576                                                 if (err)
 577                                                         ERROR(cdev,
 578                                                         "%s queue req: %d\n",
 579                                                         out_ep->name, err);
 580                                         } else
 581                                                 err = -ENOMEM;
 582                                 } else
 583                                         err = -ENOMEM;
 584                         }
 585
 586                 } else {
 587                         struct f_audio_buf *copy_buf = audio->copy_buf;
 588                         if (copy_buf) {
 589                                 list_add_tail(&copy_buf->list,
 590                                                 &audio->play_queue);
 591                                 schedule_work(&audio->playback_work);
 592                         }
 593                 }
 594         }
 595
 596         return err;
 597 }
 598
 599 static void f_audio_disable(struct usb_function *f)
 600 {
 601         return;
 602 }
 603
 604 /*-------------------------------------------------------------------------*/
 605
 606 static void f_audio_build_desc(struct f_audio *audio)
 607 {
 608         struct gaudio *card = &audio->card;
 609         u8 *sam_freq;
 610         int rate;
 611
 612         /* Set channel numbers */
 613         input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
 614         as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
 615
 616         /* Set sample rates */
 617         rate = u_audio_get_playback_rate(card);
 618         sam_freq = as_type_i_desc.tSamFreq[0];
 619         memcpy(sam_freq, &rate, 3);
 620
 621         /* Todo: Set Sample bits and other parameters */
 622
 623         return;
 624 }
 625
 626 /* audio function driver setup/binding */
 627 static int __init
 628 f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 629 {
 630         struct usb_composite_dev *cdev = c->cdev;
 631         struct f_audio          *audio = func_to_audio(f);
 632         int                     status;
 633         struct usb_ep           *ep = NULL;
 634
 635         f_audio_build_desc(audio);
 636
 637         /* allocate instance-specific interface IDs, and patch descriptors */
 638         status = usb_interface_id(c, f);
 639         if (status < 0)
 640                 goto fail;
 641         ac_interface_desc.bInterfaceNumber = status;
 642
 643         status = usb_interface_id(c, f);
 644         if (status < 0)
 645                 goto fail;
 646         as_interface_alt_0_desc.bInterfaceNumber = status;
 647         as_interface_alt_1_desc.bInterfaceNumber = status;
 648
 649         status = -ENODEV;
 650
 651         /* allocate instance-specific endpoints */
 652         ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
 653         if (!ep)
 654                 goto fail;
 655         audio->out_ep = ep;
 656         audio->out_ep->desc = &as_out_ep_desc;
 657         ep->driver_data = cdev; /* claim */
 658
 659         status = -ENOMEM;
 660
 661         /* copy descriptors, and track endpoint copies */
 662         status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL);
 663         if (status)
 664                 goto fail;
 665         return 0;
 666
 667 fail:
 668         if (ep)
 669                 ep->driver_data = NULL;
 670         return status;
 671 }
 672
 673 static void
 674 f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 675 {
 676         struct f_audio          *audio = func_to_audio(f);
 677
 678         usb_free_all_descriptors(f);
 679         kfree(audio);
 680 }
 681
 682 /*-------------------------------------------------------------------------*/
 683
 684 static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
 685 {
 686         con->data[cmd] = value;
 687
 688         return 0;
 689 }
 690
 691 static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
 692 {
 693         return con->data[cmd];
 694 }
 695
 696 /* Todo: add more control selecotor dynamically */
 697 int __init control_selector_init(struct f_audio *audio)
 698 {
 699         INIT_LIST_HEAD(&audio->cs);
 700         list_add(&feature_unit.list, &audio->cs);
 701
 702         INIT_LIST_HEAD(&feature_unit.control);
 703         list_add(&mute_control.list, &feature_unit.control);
 704         list_add(&volume_control.list, &feature_unit.control);
 705
 706         volume_control.data[UAC__CUR] = 0xffc0;
 707         volume_control.data[UAC__MIN] = 0xe3a0;
 708         volume_control.data[UAC__MAX] = 0xfff0;
 709         volume_control.data[UAC__RES] = 0x0030;
 710
 711         return 0;
 712 }
 713
 714 /**
 715  * audio_bind_config - add USB audio function to a configuration
 716  * @c: the configuration to supcard the USB audio function
 717  * Context: single threaded during gadget setup
 718  *
 719  * Returns zero on success, else negative errno.
 720  */
 721 int __init audio_bind_config(struct usb_configuration *c)
 722 {
 723         struct f_audio *audio;
 724         int status;
 725
 726         /* allocate and initialize one new instance */
 727         audio = kzalloc(sizeof *audio, GFP_KERNEL);
 728         if (!audio)
 729                 return -ENOMEM;
 730
 731         audio->card.func.name = "g_audio";
 732         audio->card.gadget = c->cdev->gadget;
 733
 734         INIT_LIST_HEAD(&audio->play_queue);
 735         spin_lock_init(&audio->lock);
 736
 737         /* set up ASLA audio devices */
 738         status = gaudio_setup(&audio->card);
 739         if (status < 0)
 740                 goto setup_fail;
 741
 742         audio->card.func.strings = audio_strings;
 743         audio->card.func.bind = f_audio_bind;
 744         audio->card.func.unbind = f_audio_unbind;
 745         audio->card.func.set_alt = f_audio_set_alt;
 746         audio->card.func.setup = f_audio_setup;
 747         audio->card.func.disable = f_audio_disable;
 748
 749         control_selector_init(audio);
 750
 751         INIT_WORK(&audio->playback_work, f_audio_playback_work);
 752
 753         status = usb_add_function(c, &audio->card.func);
 754         if (status)
 755                 goto add_fail;
 756
 757         INFO(c->cdev, "audio_buf_size %d, req_buf_size %d, req_count %d\n",
 758                 audio_buf_size, req_buf_size, req_count);
 759
 760         return status;
 761
 762 add_fail:
 763         gaudio_cleanup();
 764 setup_fail:
 765         kfree(audio);
 766         return status;
 767 }