drivers/usb/gadget/function/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/module.h>
  15 #include <linux/device.h>
  16 #include <linux/atomic.h>
  17
  18 #include "u_uac1.h"
  19
  20 static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
  21 static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
  22
  23 /*
  24  * DESCRIPTORS ... most are static, but strings and full
  25  * configuration descriptors are built on demand.
  26  */
  27
  28 /*
  29  * We have two interfaces- AudioControl and AudioStreaming
  30  * TODO: only supcard playback currently
  31  */
  32 #define F_AUDIO_AC_INTERFACE    0
  33 #define F_AUDIO_AS_INTERFACE    1
  34 #define F_AUDIO_NUM_INTERFACES  1
  35
  36 /* B.3.1  Standard AC Interface Descriptor */
  37 static struct usb_interface_descriptor ac_interface_desc = {
  38         .bLength =              USB_DT_INTERFACE_SIZE,
  39         .bDescriptorType =      USB_DT_INTERFACE,
  40         .bNumEndpoints =        0,
  41         .bInterfaceClass =      USB_CLASS_AUDIO,
  42         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOCONTROL,
  43 };
  44
  45 /*
  46  * The number of AudioStreaming and MIDIStreaming interfaces
  47  * in the Audio Interface Collection
  48  */
  49 DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
  50
  51 #define UAC_DT_AC_HEADER_LENGTH UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
  52 /* 1 input terminal, 1 output terminal and 1 feature unit */
  53 #define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
  54         + UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
  55 /* B.3.2  Class-Specific AC Interface Descriptor */
  56 static struct uac1_ac_header_descriptor_1 ac_header_desc = {
  57         .bLength =              UAC_DT_AC_HEADER_LENGTH,
  58         .bDescriptorType =      USB_DT_CS_INTERFACE,
  59         .bDescriptorSubtype =   UAC_HEADER,
  60         .bcdADC =               __constant_cpu_to_le16(0x0100),
  61         .wTotalLength =         __constant_cpu_to_le16(UAC_DT_TOTAL_LENGTH),
  62         .bInCollection =        F_AUDIO_NUM_INTERFACES,
  63         .baInterfaceNr = {
  64         /* Interface number of the first AudioStream interface */
  65                 [0] =           1,
  66         }
  67 };
  68
  69 #define INPUT_TERMINAL_ID       1
  70 static struct uac_input_terminal_descriptor input_terminal_desc = {
  71         .bLength =              UAC_DT_INPUT_TERMINAL_SIZE,
  72         .bDescriptorType =      USB_DT_CS_INTERFACE,
  73         .bDescriptorSubtype =   UAC_INPUT_TERMINAL,
  74         .bTerminalID =          INPUT_TERMINAL_ID,
  75         .wTerminalType =        UAC_TERMINAL_STREAMING,
  76         .bAssocTerminal =       0,
  77         .wChannelConfig =       0x3,
  78 };
  79
  80 DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
  81
  82 #define FEATURE_UNIT_ID         2
  83 static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
  84         .bLength                = UAC_DT_FEATURE_UNIT_SIZE(0),
  85         .bDescriptorType        = USB_DT_CS_INTERFACE,
  86         .bDescriptorSubtype     = UAC_FEATURE_UNIT,
  87         .bUnitID                = FEATURE_UNIT_ID,
  88         .bSourceID              = INPUT_TERMINAL_ID,
  89         .bControlSize           = 2,
  90         .bmaControls[0]         = (UAC_FU_MUTE | UAC_FU_VOLUME),
  91 };
  92
  93 static struct usb_audio_control mute_control = {
  94         .list = LIST_HEAD_INIT(mute_control.list),
  95         .name = "Mute Control",
  96         .type = UAC_FU_MUTE,
  97         /* Todo: add real Mute control code */
  98         .set = generic_set_cmd,
  99         .get = generic_get_cmd,
 100 };
 101
 102 static struct usb_audio_control volume_control = {
 103         .list = LIST_HEAD_INIT(volume_control.list),
 104         .name = "Volume Control",
 105         .type = UAC_FU_VOLUME,
 106         /* Todo: add real Volume control code */
 107         .set = generic_set_cmd,
 108         .get = generic_get_cmd,
 109 };
 110
 111 static struct usb_audio_control_selector feature_unit = {
 112         .list = LIST_HEAD_INIT(feature_unit.list),
 113         .id = FEATURE_UNIT_ID,
 114         .name = "Mute & Volume Control",
 115         .type = UAC_FEATURE_UNIT,
 116         .desc = (struct usb_descriptor_header *)&feature_unit_desc,
 117 };
 118
 119 #define OUTPUT_TERMINAL_ID      3
 120 static struct uac1_output_terminal_descriptor output_terminal_desc = {
 121         .bLength                = UAC_DT_OUTPUT_TERMINAL_SIZE,
 122         .bDescriptorType        = USB_DT_CS_INTERFACE,
 123         .bDescriptorSubtype     = UAC_OUTPUT_TERMINAL,
 124         .bTerminalID            = OUTPUT_TERMINAL_ID,
 125         .wTerminalType          = UAC_OUTPUT_TERMINAL_SPEAKER,
 126         .bAssocTerminal         = FEATURE_UNIT_ID,
 127         .bSourceID              = FEATURE_UNIT_ID,
 128 };
 129
 130 /* B.4.1  Standard AS Interface Descriptor */
 131 static struct usb_interface_descriptor as_interface_alt_0_desc = {
 132         .bLength =              USB_DT_INTERFACE_SIZE,
 133         .bDescriptorType =      USB_DT_INTERFACE,
 134         .bAlternateSetting =    0,
 135         .bNumEndpoints =        0,
 136         .bInterfaceClass =      USB_CLASS_AUDIO,
 137         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 138 };
 139
 140 static struct usb_interface_descriptor as_interface_alt_1_desc = {
 141         .bLength =              USB_DT_INTERFACE_SIZE,
 142         .bDescriptorType =      USB_DT_INTERFACE,
 143         .bAlternateSetting =    1,
 144         .bNumEndpoints =        1,
 145         .bInterfaceClass =      USB_CLASS_AUDIO,
 146         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 147 };
 148
 149 /* B.4.2  Class-Specific AS Interface Descriptor */
 150 static struct uac1_as_header_descriptor as_header_desc = {
 151         .bLength =              UAC_DT_AS_HEADER_SIZE,
 152         .bDescriptorType =      USB_DT_CS_INTERFACE,
 153         .bDescriptorSubtype =   UAC_AS_GENERAL,
 154         .bTerminalLink =        INPUT_TERMINAL_ID,
 155         .bDelay =               1,
 156         .wFormatTag =           UAC_FORMAT_TYPE_I_PCM,
 157 };
 158
 159 DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
 160
 161 static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
 162         .bLength =              UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
 163         .bDescriptorType =      USB_DT_CS_INTERFACE,
 164         .bDescriptorSubtype =   UAC_FORMAT_TYPE,
 165         .bFormatType =          UAC_FORMAT_TYPE_I,
 166         .bSubframeSize =        2,
 167         .bBitResolution =       16,
 168         .bSamFreqType =         1,
 169 };
 170
 171 /* Standard ISO OUT Endpoint Descriptor */
 172 static struct usb_endpoint_descriptor as_out_ep_desc  = {
 173         .bLength =              USB_DT_ENDPOINT_AUDIO_SIZE,
 174         .bDescriptorType =      USB_DT_ENDPOINT,
 175         .bEndpointAddress =     USB_DIR_OUT,
 176         .bmAttributes =         USB_ENDPOINT_SYNC_ADAPTIVE
 177                                 | USB_ENDPOINT_XFER_ISOC,
 178         .wMaxPacketSize =       cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
 179         .bInterval =            4,
 180 };
 181
 182 /* Class-specific AS ISO OUT Endpoint Descriptor */
 183 static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
 184         .bLength =              UAC_ISO_ENDPOINT_DESC_SIZE,
 185         .bDescriptorType =      USB_DT_CS_ENDPOINT,
 186         .bDescriptorSubtype =   UAC_EP_GENERAL,
 187         .bmAttributes =         1,
 188         .bLockDelayUnits =      1,
 189         .wLockDelay =           __constant_cpu_to_le16(1),
 190 };
 191
 192 static struct usb_descriptor_header *f_audio_desc[] = {
 193         (struct usb_descriptor_header *)&ac_interface_desc,
 194         (struct usb_descriptor_header *)&ac_header_desc,
 195
 196         (struct usb_descriptor_header *)&input_terminal_desc,
 197         (struct usb_descriptor_header *)&output_terminal_desc,
 198         (struct usb_descriptor_header *)&feature_unit_desc,
 199
 200         (struct usb_descriptor_header *)&as_interface_alt_0_desc,
 201         (struct usb_descriptor_header *)&as_interface_alt_1_desc,
 202         (struct usb_descriptor_header *)&as_header_desc,
 203
 204         (struct usb_descriptor_header *)&as_type_i_desc,
 205
 206         (struct usb_descriptor_header *)&as_out_ep_desc,
 207         (struct usb_descriptor_header *)&as_iso_out_desc,
 208         NULL,
 209 };
 210
 211 enum {
 212         STR_AC_IF,
 213         STR_INPUT_TERMINAL,
 214         STR_INPUT_TERMINAL_CH_NAMES,
 215         STR_FEAT_DESC_0,
 216         STR_OUTPUT_TERMINAL,
 217         STR_AS_IF_ALT0,
 218         STR_AS_IF_ALT1,
 219 };
 220
 221 static struct usb_string strings_uac1[] = {
 222         [STR_AC_IF].s = "AC Interface",
 223         [STR_INPUT_TERMINAL].s = "Input terminal",
 224         [STR_INPUT_TERMINAL_CH_NAMES].s = "Channels",
 225         [STR_FEAT_DESC_0].s = "Volume control & mute",
 226         [STR_OUTPUT_TERMINAL].s = "Output terminal",
 227         [STR_AS_IF_ALT0].s = "AS Interface",
 228         [STR_AS_IF_ALT1].s = "AS Interface",
 229         { },
 230 };
 231
 232 static struct usb_gadget_strings str_uac1 = {
 233         .language = 0x0409,     /* en-us */
 234         .strings = strings_uac1,
 235 };
 236
 237 static struct usb_gadget_strings *uac1_strings[] = {
 238         &str_uac1,
 239         NULL,
 240 };
 241
 242 /*
 243  * This function is an ALSA sound card following USB Audio Class Spec 1.0.
 244  */
 245
 246 /*-------------------------------------------------------------------------*/
 247 struct f_audio_buf {
 248         u8 *buf;
 249         int actual;
 250         struct list_head list;
 251 };
 252
 253 static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
 254 {
 255         struct f_audio_buf *copy_buf;
 256
 257         copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
 258         if (!copy_buf)
 259                 return ERR_PTR(-ENOMEM);
 260
 261         copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
 262         if (!copy_buf->buf) {
 263                 kfree(copy_buf);
 264                 return ERR_PTR(-ENOMEM);
 265         }
 266
 267         return copy_buf;
 268 }
 269
 270 static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
 271 {
 272         kfree(audio_buf->buf);
 273         kfree(audio_buf);
 274 }
 275 /*-------------------------------------------------------------------------*/
 276
 277 struct f_audio {
 278         struct gaudio                   card;
 279
 280         /* endpoints handle full and/or high speeds */
 281         struct usb_ep                   *out_ep;
 282
 283         spinlock_t                      lock;
 284         struct f_audio_buf *copy_buf;
 285         struct work_struct playback_work;
 286         struct list_head play_queue;
 287
 288         /* Control Set command */
 289         struct list_head cs;
 290         u8 set_cmd;
 291         struct usb_audio_control *set_con;
 292 };
 293
 294 static inline struct f_audio *func_to_audio(struct usb_function *f)
 295 {
 296         return container_of(f, struct f_audio, card.func);
 297 }
 298
 299 /*-------------------------------------------------------------------------*/
 300
 301 static void f_audio_playback_work(struct work_struct *data)
 302 {
 303         struct f_audio *audio = container_of(data, struct f_audio,
 304                                         playback_work);
 305         struct f_audio_buf *play_buf;
 306
 307         spin_lock_irq(&audio->lock);
 308         if (list_empty(&audio->play_queue)) {
 309                 spin_unlock_irq(&audio->lock);
 310                 return;
 311         }
 312         play_buf = list_first_entry(&audio->play_queue,
 313                         struct f_audio_buf, list);
 314         list_del(&play_buf->list);
 315         spin_unlock_irq(&audio->lock);
 316
 317         u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
 318         f_audio_buffer_free(play_buf);
 319 }
 320
 321 static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
 322 {
 323         struct f_audio *audio = req->context;
 324         struct usb_composite_dev *cdev = audio->card.func.config->cdev;
 325         struct f_audio_buf *copy_buf = audio->copy_buf;
 326         struct f_uac1_opts *opts;
 327         int audio_buf_size;
 328         int err;
 329
 330         opts = container_of(audio->card.func.fi, struct f_uac1_opts,
 331                             func_inst);
 332         audio_buf_size = opts->audio_buf_size;
 333
 334         if (!copy_buf)
 335                 return -EINVAL;
 336
 337         /* Copy buffer is full, add it to the play_queue */
 338         if (audio_buf_size - copy_buf->actual < req->actual) {
 339                 spin_lock_irq(&audio->lock);
 340                 list_add_tail(&copy_buf->list, &audio->play_queue);
 341                 spin_unlock_irq(&audio->lock);
 342                 schedule_work(&audio->playback_work);
 343                 copy_buf = f_audio_buffer_alloc(audio_buf_size);
 344                 if (IS_ERR(copy_buf))
 345                         return -ENOMEM;
 346         }
 347
 348         memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
 349         copy_buf->actual += req->actual;
 350         audio->copy_buf = copy_buf;
 351
 352         err = usb_ep_queue(ep, req, GFP_ATOMIC);
 353         if (err)
 354                 ERROR(cdev, "%s queue req: %d\n", ep->name, err);
 355
 356         return 0;
 357
 358 }
 359
 360 static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
 361 {
 362         struct f_audio *audio = req->context;
 363         int status = req->status;
 364         u32 data = 0;
 365         struct usb_ep *out_ep = audio->out_ep;
 366
 367         switch (status) {
 368
 369         case 0:                         /* normal completion? */
 370                 if (ep == out_ep)
 371                         f_audio_out_ep_complete(ep, req);
 372                 else if (audio->set_con) {
 373                         memcpy(&data, req->buf, req->length);
 374                         audio->set_con->set(audio->set_con, audio->set_cmd,
 375                                         le16_to_cpu(data));
 376                         audio->set_con = NULL;
 377                 }
 378                 break;
 379         default:
 380                 break;
 381         }
 382 }
 383
 384 static int audio_set_intf_req(struct usb_function *f,
 385                 const struct usb_ctrlrequest *ctrl)
 386 {
 387         struct f_audio          *audio = func_to_audio(f);
 388         struct usb_composite_dev *cdev = f->config->cdev;
 389         struct usb_request      *req = cdev->req;
 390         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 391         u16                     len = le16_to_cpu(ctrl->wLength);
 392         u16                     w_value = le16_to_cpu(ctrl->wValue);
 393         u8                      con_sel = (w_value >> 8) & 0xFF;
 394         u8                      cmd = (ctrl->bRequest & 0x0F);
 395         struct usb_audio_control_selector *cs;
 396         struct usb_audio_control *con;
 397
 398         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 399                         ctrl->bRequest, w_value, len, id);
 400
 401         list_for_each_entry(cs, &audio->cs, list) {
 402                 if (cs->id == id) {
 403                         list_for_each_entry(con, &cs->control, list) {
 404                                 if (con->type == con_sel) {
 405                                         audio->set_con = con;
 406                                         break;
 407                                 }
 408                         }
 409                         break;
 410                 }
 411         }
 412
 413         audio->set_cmd = cmd;
 414         req->context = audio;
 415         req->complete = f_audio_complete;
 416
 417         return len;
 418 }
 419
 420 static int audio_get_intf_req(struct usb_function *f,
 421                 const struct usb_ctrlrequest *ctrl)
 422 {
 423         struct f_audio          *audio = func_to_audio(f);
 424         struct usb_composite_dev *cdev = f->config->cdev;
 425         struct usb_request      *req = cdev->req;
 426         int                     value = -EOPNOTSUPP;
 427         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 428         u16                     len = le16_to_cpu(ctrl->wLength);
 429         u16                     w_value = le16_to_cpu(ctrl->wValue);
 430         u8                      con_sel = (w_value >> 8) & 0xFF;
 431         u8                      cmd = (ctrl->bRequest & 0x0F);
 432         struct usb_audio_control_selector *cs;
 433         struct usb_audio_control *con;
 434
 435         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 436                         ctrl->bRequest, w_value, len, id);
 437
 438         list_for_each_entry(cs, &audio->cs, list) {
 439                 if (cs->id == id) {
 440                         list_for_each_entry(con, &cs->control, list) {
 441                                 if (con->type == con_sel && con->get) {
 442                                         value = con->get(con, cmd);
 443                                         break;
 444                                 }
 445                         }
 446                         break;
 447                 }
 448         }
 449
 450         req->context = audio;
 451         req->complete = f_audio_complete;
 452         len = min_t(size_t, sizeof(value), len);
 453         memcpy(req->buf, &value, len);
 454
 455         return len;
 456 }
 457
 458 static int audio_set_endpoint_req(struct usb_function *f,
 459                 const struct usb_ctrlrequest *ctrl)
 460 {
 461         struct usb_composite_dev *cdev = f->config->cdev;
 462         int                     value = -EOPNOTSUPP;
 463         u16                     ep = le16_to_cpu(ctrl->wIndex);
 464         u16                     len = le16_to_cpu(ctrl->wLength);
 465         u16                     w_value = le16_to_cpu(ctrl->wValue);
 466
 467         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 468                         ctrl->bRequest, w_value, len, ep);
 469
 470         switch (ctrl->bRequest) {
 471         case UAC_SET_CUR:
 472                 value = len;
 473                 break;
 474
 475         case UAC_SET_MIN:
 476                 break;
 477
 478         case UAC_SET_MAX:
 479                 break;
 480
 481         case UAC_SET_RES:
 482                 break;
 483
 484         case UAC_SET_MEM:
 485                 break;
 486
 487         default:
 488                 break;
 489         }
 490
 491         return value;
 492 }
 493
 494 static int audio_get_endpoint_req(struct usb_function *f,
 495                 const struct usb_ctrlrequest *ctrl)
 496 {
 497         struct usb_composite_dev *cdev = f->config->cdev;
 498         int value = -EOPNOTSUPP;
 499         u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 500         u16 len = le16_to_cpu(ctrl->wLength);
 501         u16 w_value = le16_to_cpu(ctrl->wValue);
 502
 503         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 504                         ctrl->bRequest, w_value, len, ep);
 505
 506         switch (ctrl->bRequest) {
 507         case UAC_GET_CUR:
 508         case UAC_GET_MIN:
 509         case UAC_GET_MAX:
 510         case UAC_GET_RES:
 511                 value = len;
 512                 break;
 513         case UAC_GET_MEM:
 514                 break;
 515         default:
 516                 break;
 517         }
 518
 519         return value;
 520 }
 521
 522 static int
 523 f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 524 {
 525         struct usb_composite_dev *cdev = f->config->cdev;
 526         struct usb_request      *req = cdev->req;
 527         int                     value = -EOPNOTSUPP;
 528         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 529         u16                     w_value = le16_to_cpu(ctrl->wValue);
 530         u16                     w_length = le16_to_cpu(ctrl->wLength);
 531
 532         /* composite driver infrastructure handles everything; interface
 533          * activation uses set_alt().
 534          */
 535         switch (ctrl->bRequestType) {
 536         case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 537                 value = audio_set_intf_req(f, ctrl);
 538                 break;
 539
 540         case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 541                 value = audio_get_intf_req(f, ctrl);
 542                 break;
 543
 544         case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 545                 value = audio_set_endpoint_req(f, ctrl);
 546                 break;
 547
 548         case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 549                 value = audio_get_endpoint_req(f, ctrl);
 550                 break;
 551
 552         default:
 553                 ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 554                         ctrl->bRequestType, ctrl->bRequest,
 555                         w_value, w_index, w_length);
 556         }
 557
 558         /* respond with data transfer or status phase? */
 559         if (value >= 0) {
 560                 DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
 561                         ctrl->bRequestType, ctrl->bRequest,
 562                         w_value, w_index, w_length);
 563                 req->zero = 0;
 564                 req->length = value;
 565                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 566                 if (value < 0)
 567                         ERROR(cdev, "audio response on err %d\n", value);
 568         }
 569
 570         /* device either stalls (value < 0) or reports success */
 571         return value;
 572 }
 573
 574 static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 575 {
 576         struct f_audio          *audio = func_to_audio(f);
 577         struct usb_composite_dev *cdev = f->config->cdev;
 578         struct usb_ep *out_ep = audio->out_ep;
 579         struct usb_request *req;
 580         struct f_uac1_opts *opts;
 581         int req_buf_size, req_count, audio_buf_size;
 582         int i = 0, err = 0;
 583
 584         DBG(cdev, "intf %d, alt %d\n", intf, alt);
 585
 586         opts = container_of(f->fi, struct f_uac1_opts, func_inst);
 587         req_buf_size = opts->req_buf_size;
 588         req_count = opts->req_count;
 589         audio_buf_size = opts->audio_buf_size;
 590
 591         if (intf == 1) {
 592                 if (alt == 1) {
 593                         err = config_ep_by_speed(cdev->gadget, f, out_ep);
 594                         if (err)
 595                                 return err;
 596
 597                         usb_ep_enable(out_ep);
 598                         audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
 599                         if (IS_ERR(audio->copy_buf))
 600                                 return -ENOMEM;
 601
 602                         /*
 603                          * allocate a bunch of read buffers
 604                          * and queue them all at once.
 605                          */
 606                         for (i = 0; i < req_count && err == 0; i++) {
 607                                 req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
 608                                 if (req) {
 609                                         req->buf = kzalloc(req_buf_size,
 610                                                         GFP_ATOMIC);
 611                                         if (req->buf) {
 612                                                 req->length = req_buf_size;
 613                                                 req->context = audio;
 614                                                 req->complete =
 615                                                         f_audio_complete;
 616                                                 err = usb_ep_queue(out_ep,
 617                                                         req, GFP_ATOMIC);
 618                                                 if (err)
 619                                                         ERROR(cdev,
 620                                                         "%s queue req: %d\n",
 621                                                         out_ep->name, err);
 622                                         } else
 623                                                 err = -ENOMEM;
 624                                 } else
 625                                         err = -ENOMEM;
 626                         }
 627
 628                 } else {
 629                         struct f_audio_buf *copy_buf = audio->copy_buf;
 630                         if (copy_buf) {
 631                                 list_add_tail(&copy_buf->list,
 632                                                 &audio->play_queue);
 633                                 schedule_work(&audio->playback_work);
 634                         }
 635                 }
 636         }
 637
 638         return err;
 639 }
 640
 641 static void f_audio_disable(struct usb_function *f)
 642 {
 643         return;
 644 }
 645
 646 /*-------------------------------------------------------------------------*/
 647
 648 static void f_audio_build_desc(struct f_audio *audio)
 649 {
 650         struct gaudio *card = &audio->card;
 651         u8 *sam_freq;
 652         int rate;
 653
 654         /* Set channel numbers */
 655         input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
 656         as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
 657
 658         /* Set sample rates */
 659         rate = u_audio_get_playback_rate(card);
 660         sam_freq = as_type_i_desc.tSamFreq[0];
 661         memcpy(sam_freq, &rate, 3);
 662
 663         /* Todo: Set Sample bits and other parameters */
 664
 665         return;
 666 }
 667
 668 /* audio function driver setup/binding */
 669 static int
 670 f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 671 {
 672         struct usb_composite_dev *cdev = c->cdev;
 673         struct f_audio          *audio = func_to_audio(f);
 674         struct usb_string       *us;
 675         int                     status;
 676         struct usb_ep           *ep = NULL;
 677         struct f_uac1_opts      *audio_opts;
 678
 679         audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst);
 680         audio->card.gadget = c->cdev->gadget;
 681         /* set up ASLA audio devices */
 682         if (!audio_opts->bound) {
 683                 status = gaudio_setup(&audio->card);
 684                 if (status < 0)
 685                         return status;
 686                 audio_opts->bound = true;
 687         }
 688         us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
 689         if (IS_ERR(us))
 690                 return PTR_ERR(us);
 691         ac_interface_desc.iInterface = us[STR_AC_IF].id;
 692         input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
 693         input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
 694         feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
 695         output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
 696         as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
 697         as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
 698
 699
 700         f_audio_build_desc(audio);
 701
 702         /* allocate instance-specific interface IDs, and patch descriptors */
 703         status = usb_interface_id(c, f);
 704         if (status < 0)
 705                 goto fail;
 706         ac_interface_desc.bInterfaceNumber = status;
 707
 708         status = usb_interface_id(c, f);
 709         if (status < 0)
 710                 goto fail;
 711         as_interface_alt_0_desc.bInterfaceNumber = status;
 712         as_interface_alt_1_desc.bInterfaceNumber = status;
 713
 714         status = -ENODEV;
 715
 716         /* allocate instance-specific endpoints */
 717         ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
 718         if (!ep)
 719                 goto fail;
 720         audio->out_ep = ep;
 721         audio->out_ep->desc = &as_out_ep_desc;
 722
 723         status = -ENOMEM;
 724
 725         /* copy descriptors, and track endpoint copies */
 726         status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
 727                                         NULL);
 728         if (status)
 729                 goto fail;
 730         return 0;
 731
 732 fail:
 733         gaudio_cleanup(&audio->card);
 734         return status;
 735 }
 736
 737 /*-------------------------------------------------------------------------*/
 738
 739 static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
 740 {
 741         con->data[cmd] = value;
 742
 743         return 0;
 744 }
 745
 746 static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
 747 {
 748         return con->data[cmd];
 749 }
 750
 751 /* Todo: add more control selecotor dynamically */
 752 static int control_selector_init(struct f_audio *audio)
 753 {
 754         INIT_LIST_HEAD(&audio->cs);
 755         list_add(&feature_unit.list, &audio->cs);
 756
 757         INIT_LIST_HEAD(&feature_unit.control);
 758         list_add(&mute_control.list, &feature_unit.control);
 759         list_add(&volume_control.list, &feature_unit.control);
 760
 761         volume_control.data[UAC__CUR] = 0xffc0;
 762         volume_control.data[UAC__MIN] = 0xe3a0;
 763         volume_control.data[UAC__MAX] = 0xfff0;
 764         volume_control.data[UAC__RES] = 0x0030;
 765
 766         return 0;
 767 }
 768
 769 static inline struct f_uac1_opts *to_f_uac1_opts(struct config_item *item)
 770 {
 771         return container_of(to_config_group(item), struct f_uac1_opts,
 772                             func_inst.group);
 773 }
 774
 775 static void f_uac1_attr_release(struct config_item *item)
 776 {
 777         struct f_uac1_opts *opts = to_f_uac1_opts(item);
 778
 779         usb_put_function_instance(&opts->func_inst);
 780 }
 781
 782 static struct configfs_item_operations f_uac1_item_ops = {
 783         .release        = f_uac1_attr_release,
 784 };
 785
 786 #define UAC1_INT_ATTRIBUTE(name)                                        \
 787 static ssize_t f_uac1_opts_##name##_show(struct config_item *item,      \
 788                                          char *page)                    \
 789 {                                                                       \
 790         struct f_uac1_opts *opts = to_f_uac1_opts(item);                \
 791         int result;                                                     \
 792                                                                         \
 793         mutex_lock(&opts->lock);                                        \
 794         result = sprintf(page, "%u\n", opts->name);                     \
 795         mutex_unlock(&opts->lock);                                      \
 796                                                                         \
 797         return result;                                                  \
 798 }                                                                       \
 799                                                                         \
 800 static ssize_t f_uac1_opts_##name##_store(struct config_item *item,             \
 801                                           const char *page, size_t len) \
 802 {                                                                       \
 803         struct f_uac1_opts *opts = to_f_uac1_opts(item);                \
 804         int ret;                                                        \
 805         u32 num;                                                        \
 806                                                                         \
 807         mutex_lock(&opts->lock);                                        \
 808         if (opts->refcnt) {                                             \
 809                 ret = -EBUSY;                                           \
 810                 goto end;                                               \
 811         }                                                               \
 812                                                                         \
 813         ret = kstrtou32(page, 0, &num);                                 \
 814         if (ret)                                                        \
 815                 goto end;                                               \
 816                                                                         \
 817         opts->name = num;                                               \
 818         ret = len;                                                      \
 819                                                                         \
 820 end:                                                                    \
 821         mutex_unlock(&opts->lock);                                      \
 822         return ret;                                                     \
 823 }                                                                       \
 824                                                                         \
 825 CONFIGFS_ATTR(f_uac1_opts_, name)
 826
 827 UAC1_INT_ATTRIBUTE(req_buf_size);
 828 UAC1_INT_ATTRIBUTE(req_count);
 829 UAC1_INT_ATTRIBUTE(audio_buf_size);
 830
 831 #define UAC1_STR_ATTRIBUTE(name)                                        \
 832 static ssize_t f_uac1_opts_##name##_show(struct config_item *item,      \
 833                                          char *page)                    \
 834 {                                                                       \
 835         struct f_uac1_opts *opts = to_f_uac1_opts(item);                \
 836         int result;                                                     \
 837                                                                         \
 838         mutex_lock(&opts->lock);                                        \
 839         result = sprintf(page, "%s\n", opts->name);                     \
 840         mutex_unlock(&opts->lock);                                      \
 841                                                                         \
 842         return result;                                                  \
 843 }                                                                       \
 844                                                                         \
 845 static ssize_t f_uac1_opts_##name##_store(struct config_item *item,     \
 846                                           const char *page, size_t len) \
 847 {                                                                       \
 848         struct f_uac1_opts *opts = to_f_uac1_opts(item);                \
 849         int ret = -EBUSY;                                               \
 850         char *tmp;                                                      \
 851                                                                         \
 852         mutex_lock(&opts->lock);                                        \
 853         if (opts->refcnt)                                               \
 854                 goto end;                                               \
 855                                                                         \
 856         tmp = kstrndup(page, len, GFP_KERNEL);                          \
 857         if (tmp) {                                                      \
 858                 ret = -ENOMEM;                                          \
 859                 goto end;                                               \
 860         }                                                               \
 861         if (opts->name##_alloc)                                         \
 862                 kfree(opts->name);                                      \
 863         opts->name##_alloc = true;                                      \
 864         opts->name = tmp;                                               \
 865         ret = len;                                                      \
 866                                                                         \
 867 end:                                                                    \
 868         mutex_unlock(&opts->lock);                                      \
 869         return ret;                                                     \
 870 }                                                                       \
 871                                                                         \
 872 CONFIGFS_ATTR(f_uac1_opts_, name)
 873
 874 UAC1_STR_ATTRIBUTE(fn_play);
 875 UAC1_STR_ATTRIBUTE(fn_cap);
 876 UAC1_STR_ATTRIBUTE(fn_cntl);
 877
 878 static struct configfs_attribute *f_uac1_attrs[] = {
 879         &f_uac1_opts_attr_req_buf_size,
 880         &f_uac1_opts_attr_req_count,
 881         &f_uac1_opts_attr_audio_buf_size,
 882         &f_uac1_opts_attr_fn_play,
 883         &f_uac1_opts_attr_fn_cap,
 884         &f_uac1_opts_attr_fn_cntl,
 885         NULL,
 886 };
 887
 888 static struct config_item_type f_uac1_func_type = {
 889         .ct_item_ops    = &f_uac1_item_ops,
 890         .ct_attrs       = f_uac1_attrs,
 891         .ct_owner       = THIS_MODULE,
 892 };
 893
 894 static void f_audio_free_inst(struct usb_function_instance *f)
 895 {
 896         struct f_uac1_opts *opts;
 897
 898         opts = container_of(f, struct f_uac1_opts, func_inst);
 899         if (opts->fn_play_alloc)
 900                 kfree(opts->fn_play);
 901         if (opts->fn_cap_alloc)
 902                 kfree(opts->fn_cap);
 903         if (opts->fn_cntl_alloc)
 904                 kfree(opts->fn_cntl);
 905         kfree(opts);
 906 }
 907
 908 static struct usb_function_instance *f_audio_alloc_inst(void)
 909 {
 910         struct f_uac1_opts *opts;
 911
 912         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 913         if (!opts)
 914                 return ERR_PTR(-ENOMEM);
 915
 916         mutex_init(&opts->lock);
 917         opts->func_inst.free_func_inst = f_audio_free_inst;
 918
 919         config_group_init_type_name(&opts->func_inst.group, "",
 920                                     &f_uac1_func_type);
 921
 922         opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
 923         opts->req_count = UAC1_REQ_COUNT;
 924         opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
 925         opts->fn_play = FILE_PCM_PLAYBACK;
 926         opts->fn_cap = FILE_PCM_CAPTURE;
 927         opts->fn_cntl = FILE_CONTROL;
 928         return &opts->func_inst;
 929 }
 930
 931 static void f_audio_free(struct usb_function *f)
 932 {
 933         struct f_audio *audio = func_to_audio(f);
 934         struct f_uac1_opts *opts;
 935
 936         gaudio_cleanup(&audio->card);
 937         opts = container_of(f->fi, struct f_uac1_opts, func_inst);
 938         kfree(audio);
 939         mutex_lock(&opts->lock);
 940         --opts->refcnt;
 941         mutex_unlock(&opts->lock);
 942 }
 943
 944 static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 945 {
 946         usb_free_all_descriptors(f);
 947 }
 948
 949 static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
 950 {
 951         struct f_audio *audio;
 952         struct f_uac1_opts *opts;
 953
 954         /* allocate and initialize one new instance */
 955         audio = kzalloc(sizeof(*audio), GFP_KERNEL);
 956         if (!audio)
 957                 return ERR_PTR(-ENOMEM);
 958
 959         audio->card.func.name = "g_audio";
 960
 961         opts = container_of(fi, struct f_uac1_opts, func_inst);
 962         mutex_lock(&opts->lock);
 963         ++opts->refcnt;
 964         mutex_unlock(&opts->lock);
 965         INIT_LIST_HEAD(&audio->play_queue);
 966         spin_lock_init(&audio->lock);
 967
 968         audio->card.func.bind = f_audio_bind;
 969         audio->card.func.unbind = f_audio_unbind;
 970         audio->card.func.set_alt = f_audio_set_alt;
 971         audio->card.func.setup = f_audio_setup;
 972         audio->card.func.disable = f_audio_disable;
 973         audio->card.func.free_func = f_audio_free;
 974
 975         control_selector_init(audio);
 976
 977         INIT_WORK(&audio->playback_work, f_audio_playback_work);
 978
 979         return &audio->card.func;
 980 }
 981
 982 DECLARE_USB_FUNCTION_INIT(uac1, f_audio_alloc_inst, f_audio_alloc);
 983 MODULE_LICENSE("GPL");
 984 MODULE_AUTHOR("Bryan Wu");