drivers/usb/gadget/function/f_uac1_legacy.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_legacy.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         u8 ac_intf, ac_alt;
 281         u8 as_intf, as_alt;
 282
 283         /* endpoints handle full and/or high speeds */
 284         struct usb_ep                   *out_ep;
 285
 286         spinlock_t                      lock;
 287         struct f_audio_buf *copy_buf;
 288         struct work_struct playback_work;
 289         struct list_head play_queue;
 290
 291         /* Control Set command */
 292         struct list_head cs;
 293         u8 set_cmd;
 294         struct usb_audio_control *set_con;
 295 };
 296
 297 static inline struct f_audio *func_to_audio(struct usb_function *f)
 298 {
 299         return container_of(f, struct f_audio, card.func);
 300 }
 301
 302 /*-------------------------------------------------------------------------*/
 303
 304 static void f_audio_playback_work(struct work_struct *data)
 305 {
 306         struct f_audio *audio = container_of(data, struct f_audio,
 307                                         playback_work);
 308         struct f_audio_buf *play_buf;
 309
 310         spin_lock_irq(&audio->lock);
 311         if (list_empty(&audio->play_queue)) {
 312                 spin_unlock_irq(&audio->lock);
 313                 return;
 314         }
 315         play_buf = list_first_entry(&audio->play_queue,
 316                         struct f_audio_buf, list);
 317         list_del(&play_buf->list);
 318         spin_unlock_irq(&audio->lock);
 319
 320         u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
 321         f_audio_buffer_free(play_buf);
 322 }
 323
 324 static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
 325 {
 326         struct f_audio *audio = req->context;
 327         struct usb_composite_dev *cdev = audio->card.func.config->cdev;
 328         struct f_audio_buf *copy_buf = audio->copy_buf;
 329         struct f_uac1_legacy_opts *opts;
 330         int audio_buf_size;
 331         int err;
 332
 333         opts = container_of(audio->card.func.fi, struct f_uac1_legacy_opts,
 334                             func_inst);
 335         audio_buf_size = opts->audio_buf_size;
 336
 337         if (!copy_buf)
 338                 return -EINVAL;
 339
 340         /* Copy buffer is full, add it to the play_queue */
 341         if (audio_buf_size - copy_buf->actual < req->actual) {
 342                 spin_lock_irq(&audio->lock);
 343                 list_add_tail(&copy_buf->list, &audio->play_queue);
 344                 spin_unlock_irq(&audio->lock);
 345                 schedule_work(&audio->playback_work);
 346                 copy_buf = f_audio_buffer_alloc(audio_buf_size);
 347                 if (IS_ERR(copy_buf))
 348                         return -ENOMEM;
 349         }
 350
 351         memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
 352         copy_buf->actual += req->actual;
 353         audio->copy_buf = copy_buf;
 354
 355         err = usb_ep_queue(ep, req, GFP_ATOMIC);
 356         if (err)
 357                 ERROR(cdev, "%s queue req: %d\n", ep->name, err);
 358
 359         return 0;
 360
 361 }
 362
 363 static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
 364 {
 365         struct f_audio *audio = req->context;
 366         int status = req->status;
 367         u32 data = 0;
 368         struct usb_ep *out_ep = audio->out_ep;
 369
 370         switch (status) {
 371
 372         case 0:                         /* normal completion? */
 373                 if (ep == out_ep)
 374                         f_audio_out_ep_complete(ep, req);
 375                 else if (audio->set_con) {
 376                         memcpy(&data, req->buf, req->length);
 377                         audio->set_con->set(audio->set_con, audio->set_cmd,
 378                                         le16_to_cpu(data));
 379                         audio->set_con = NULL;
 380                 }
 381                 break;
 382         default:
 383                 break;
 384         }
 385 }
 386
 387 static int audio_set_intf_req(struct usb_function *f,
 388                 const struct usb_ctrlrequest *ctrl)
 389 {
 390         struct f_audio          *audio = func_to_audio(f);
 391         struct usb_composite_dev *cdev = f->config->cdev;
 392         struct usb_request      *req = cdev->req;
 393         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 394         u16                     len = le16_to_cpu(ctrl->wLength);
 395         u16                     w_value = le16_to_cpu(ctrl->wValue);
 396         u8                      con_sel = (w_value >> 8) & 0xFF;
 397         u8                      cmd = (ctrl->bRequest & 0x0F);
 398         struct usb_audio_control_selector *cs;
 399         struct usb_audio_control *con;
 400
 401         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 402                         ctrl->bRequest, w_value, len, id);
 403
 404         list_for_each_entry(cs, &audio->cs, list) {
 405                 if (cs->id == id) {
 406                         list_for_each_entry(con, &cs->control, list) {
 407                                 if (con->type == con_sel) {
 408                                         audio->set_con = con;
 409                                         break;
 410                                 }
 411                         }
 412                         break;
 413                 }
 414         }
 415
 416         audio->set_cmd = cmd;
 417         req->context = audio;
 418         req->complete = f_audio_complete;
 419
 420         return len;
 421 }
 422
 423 static int audio_get_intf_req(struct usb_function *f,
 424                 const struct usb_ctrlrequest *ctrl)
 425 {
 426         struct f_audio          *audio = func_to_audio(f);
 427         struct usb_composite_dev *cdev = f->config->cdev;
 428         struct usb_request      *req = cdev->req;
 429         int                     value = -EOPNOTSUPP;
 430         u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 431         u16                     len = le16_to_cpu(ctrl->wLength);
 432         u16                     w_value = le16_to_cpu(ctrl->wValue);
 433         u8                      con_sel = (w_value >> 8) & 0xFF;
 434         u8                      cmd = (ctrl->bRequest & 0x0F);
 435         struct usb_audio_control_selector *cs;
 436         struct usb_audio_control *con;
 437
 438         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 439                         ctrl->bRequest, w_value, len, id);
 440
 441         list_for_each_entry(cs, &audio->cs, list) {
 442                 if (cs->id == id) {
 443                         list_for_each_entry(con, &cs->control, list) {
 444                                 if (con->type == con_sel && con->get) {
 445                                         value = con->get(con, cmd);
 446                                         break;
 447                                 }
 448                         }
 449                         break;
 450                 }
 451         }
 452
 453         req->context = audio;
 454         req->complete = f_audio_complete;
 455         len = min_t(size_t, sizeof(value), len);
 456         memcpy(req->buf, &value, len);
 457
 458         return len;
 459 }
 460
 461 static int audio_set_endpoint_req(struct usb_function *f,
 462                 const struct usb_ctrlrequest *ctrl)
 463 {
 464         struct usb_composite_dev *cdev = f->config->cdev;
 465         int                     value = -EOPNOTSUPP;
 466         u16                     ep = le16_to_cpu(ctrl->wIndex);
 467         u16                     len = le16_to_cpu(ctrl->wLength);
 468         u16                     w_value = le16_to_cpu(ctrl->wValue);
 469
 470         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 471                         ctrl->bRequest, w_value, len, ep);
 472
 473         switch (ctrl->bRequest) {
 474         case UAC_SET_CUR:
 475                 value = len;
 476                 break;
 477
 478         case UAC_SET_MIN:
 479                 break;
 480
 481         case UAC_SET_MAX:
 482                 break;
 483
 484         case UAC_SET_RES:
 485                 break;
 486
 487         case UAC_SET_MEM:
 488                 break;
 489
 490         default:
 491                 break;
 492         }
 493
 494         return value;
 495 }
 496
 497 static int audio_get_endpoint_req(struct usb_function *f,
 498                 const struct usb_ctrlrequest *ctrl)
 499 {
 500         struct usb_composite_dev *cdev = f->config->cdev;
 501         int value = -EOPNOTSUPP;
 502         u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 503         u16 len = le16_to_cpu(ctrl->wLength);
 504         u16 w_value = le16_to_cpu(ctrl->wValue);
 505
 506         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 507                         ctrl->bRequest, w_value, len, ep);
 508
 509         switch (ctrl->bRequest) {
 510         case UAC_GET_CUR:
 511         case UAC_GET_MIN:
 512         case UAC_GET_MAX:
 513         case UAC_GET_RES:
 514                 value = len;
 515                 break;
 516         case UAC_GET_MEM:
 517                 break;
 518         default:
 519                 break;
 520         }
 521
 522         return value;
 523 }
 524
 525 static int
 526 f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 527 {
 528         struct usb_composite_dev *cdev = f->config->cdev;
 529         struct usb_request      *req = cdev->req;
 530         int                     value = -EOPNOTSUPP;
 531         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 532         u16                     w_value = le16_to_cpu(ctrl->wValue);
 533         u16                     w_length = le16_to_cpu(ctrl->wLength);
 534
 535         /* composite driver infrastructure handles everything; interface
 536          * activation uses set_alt().
 537          */
 538         switch (ctrl->bRequestType) {
 539         case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 540                 value = audio_set_intf_req(f, ctrl);
 541                 break;
 542
 543         case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 544                 value = audio_get_intf_req(f, ctrl);
 545                 break;
 546
 547         case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 548                 value = audio_set_endpoint_req(f, ctrl);
 549                 break;
 550
 551         case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 552                 value = audio_get_endpoint_req(f, ctrl);
 553                 break;
 554
 555         default:
 556                 ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 557                         ctrl->bRequestType, ctrl->bRequest,
 558                         w_value, w_index, w_length);
 559         }
 560
 561         /* respond with data transfer or status phase? */
 562         if (value >= 0) {
 563                 DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
 564                         ctrl->bRequestType, ctrl->bRequest,
 565                         w_value, w_index, w_length);
 566                 req->zero = 0;
 567                 req->length = value;
 568                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 569                 if (value < 0)
 570                         ERROR(cdev, "audio response on err %d\n", value);
 571         }
 572
 573         /* device either stalls (value < 0) or reports success */
 574         return value;
 575 }
 576
 577 static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 578 {
 579         struct f_audio          *audio = func_to_audio(f);
 580         struct usb_composite_dev *cdev = f->config->cdev;
 581         struct usb_ep *out_ep = audio->out_ep;
 582         struct usb_request *req;
 583         struct f_uac1_legacy_opts *opts;
 584         int req_buf_size, req_count, audio_buf_size;
 585         int i = 0, err = 0;
 586
 587         DBG(cdev, "intf %d, alt %d\n", intf, alt);
 588
 589         opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
 590         req_buf_size = opts->req_buf_size;
 591         req_count = opts->req_count;
 592         audio_buf_size = opts->audio_buf_size;
 593
 594         /* No i/f has more than 2 alt settings */
 595         if (alt > 1) {
 596                 ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
 597                 return -EINVAL;
 598         }
 599
 600         if (intf == audio->ac_intf) {
 601                 /* Control I/f has only 1 AltSetting - 0 */
 602                 if (alt) {
 603                         ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
 604                         return -EINVAL;
 605                 }
 606                 return 0;
 607         } else if (intf == audio->as_intf) {
 608                 if (alt == 1) {
 609                         err = config_ep_by_speed(cdev->gadget, f, out_ep);
 610                         if (err)
 611                                 return err;
 612
 613                         usb_ep_enable(out_ep);
 614                         audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
 615                         if (IS_ERR(audio->copy_buf))
 616                                 return -ENOMEM;
 617
 618                         /*
 619                          * allocate a bunch of read buffers
 620                          * and queue them all at once.
 621                          */
 622                         for (i = 0; i < req_count && err == 0; i++) {
 623                                 req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
 624                                 if (req) {
 625                                         req->buf = kzalloc(req_buf_size,
 626                                                         GFP_ATOMIC);
 627                                         if (req->buf) {
 628                                                 req->length = req_buf_size;
 629                                                 req->context = audio;
 630                                                 req->complete =
 631                                                         f_audio_complete;
 632                                                 err = usb_ep_queue(out_ep,
 633                                                         req, GFP_ATOMIC);
 634                                                 if (err)
 635                                                         ERROR(cdev,
 636                                                         "%s queue req: %d\n",
 637                                                         out_ep->name, err);
 638                                         } else
 639                                                 err = -ENOMEM;
 640                                 } else
 641                                         err = -ENOMEM;
 642                         }
 643
 644                 } else {
 645                         struct f_audio_buf *copy_buf = audio->copy_buf;
 646                         if (copy_buf) {
 647                                 list_add_tail(&copy_buf->list,
 648                                                 &audio->play_queue);
 649                                 schedule_work(&audio->playback_work);
 650                         }
 651                 }
 652                 audio->as_alt = alt;
 653         }
 654
 655         return err;
 656 }
 657
 658 static int f_audio_get_alt(struct usb_function *f, unsigned intf)
 659 {
 660         struct f_audio          *audio = func_to_audio(f);
 661         struct usb_composite_dev *cdev = f->config->cdev;
 662
 663         if (intf == audio->ac_intf)
 664                 return audio->ac_alt;
 665         else if (intf == audio->as_intf)
 666                 return audio->as_alt;
 667         else
 668                 ERROR(cdev, "%s:%d Invalid Interface %d!\n",
 669                       __func__, __LINE__, intf);
 670
 671         return -EINVAL;
 672 }
 673
 674 static void f_audio_disable(struct usb_function *f)
 675 {
 676         return;
 677 }
 678
 679 /*-------------------------------------------------------------------------*/
 680
 681 static void f_audio_build_desc(struct f_audio *audio)
 682 {
 683         struct gaudio *card = &audio->card;
 684         u8 *sam_freq;
 685         int rate;
 686
 687         /* Set channel numbers */
 688         input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
 689         as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
 690
 691         /* Set sample rates */
 692         rate = u_audio_get_playback_rate(card);
 693         sam_freq = as_type_i_desc.tSamFreq[0];
 694         memcpy(sam_freq, &rate, 3);
 695
 696         /* Todo: Set Sample bits and other parameters */
 697
 698         return;
 699 }
 700
 701 /* audio function driver setup/binding */
 702 static int
 703 f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 704 {
 705         struct usb_composite_dev *cdev = c->cdev;
 706         struct f_audio          *audio = func_to_audio(f);
 707         struct usb_string       *us;
 708         int                     status;
 709         struct usb_ep           *ep = NULL;
 710         struct f_uac1_legacy_opts       *audio_opts;
 711
 712         audio_opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
 713         audio->card.gadget = c->cdev->gadget;
 714         /* set up ASLA audio devices */
 715         if (!audio_opts->bound) {
 716                 status = gaudio_setup(&audio->card);
 717                 if (status < 0)
 718                         return status;
 719                 audio_opts->bound = true;
 720         }
 721         us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
 722         if (IS_ERR(us))
 723                 return PTR_ERR(us);
 724         ac_interface_desc.iInterface = us[STR_AC_IF].id;
 725         input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
 726         input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
 727         feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
 728         output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
 729         as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
 730         as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
 731
 732
 733         f_audio_build_desc(audio);
 734
 735         /* allocate instance-specific interface IDs, and patch descriptors */
 736         status = usb_interface_id(c, f);
 737         if (status < 0)
 738                 goto fail;
 739         ac_interface_desc.bInterfaceNumber = status;
 740         audio->ac_intf = status;
 741         audio->ac_alt = 0;
 742
 743         status = usb_interface_id(c, f);
 744         if (status < 0)
 745                 goto fail;
 746         as_interface_alt_0_desc.bInterfaceNumber = status;
 747         as_interface_alt_1_desc.bInterfaceNumber = status;
 748         audio->as_intf = status;
 749         audio->as_alt = 0;
 750
 751         status = -ENODEV;
 752
 753         /* allocate instance-specific endpoints */
 754         ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
 755         if (!ep)
 756                 goto fail;
 757         audio->out_ep = ep;
 758         audio->out_ep->desc = &as_out_ep_desc;
 759
 760         status = -ENOMEM;
 761
 762         /* copy descriptors, and track endpoint copies */
 763         status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
 764                                         NULL);
 765         if (status)
 766                 goto fail;
 767         return 0;
 768
 769 fail:
 770         gaudio_cleanup(&audio->card);
 771         return status;
 772 }
 773
 774 /*-------------------------------------------------------------------------*/
 775
 776 static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
 777 {
 778         con->data[cmd] = value;
 779
 780         return 0;
 781 }
 782
 783 static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
 784 {
 785         return con->data[cmd];
 786 }
 787
 788 /* Todo: add more control selecotor dynamically */
 789 static int control_selector_init(struct f_audio *audio)
 790 {
 791         INIT_LIST_HEAD(&audio->cs);
 792         list_add(&feature_unit.list, &audio->cs);
 793
 794         INIT_LIST_HEAD(&feature_unit.control);
 795         list_add(&mute_control.list, &feature_unit.control);
 796         list_add(&volume_control.list, &feature_unit.control);
 797
 798         volume_control.data[UAC__CUR] = 0xffc0;
 799         volume_control.data[UAC__MIN] = 0xe3a0;
 800         volume_control.data[UAC__MAX] = 0xfff0;
 801         volume_control.data[UAC__RES] = 0x0030;
 802
 803         return 0;
 804 }
 805
 806 static inline
 807 struct f_uac1_legacy_opts *to_f_uac1_opts(struct config_item *item)
 808 {
 809         return container_of(to_config_group(item), struct f_uac1_legacy_opts,
 810                             func_inst.group);
 811 }
 812
 813 static void f_uac1_attr_release(struct config_item *item)
 814 {
 815         struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);
 816
 817         usb_put_function_instance(&opts->func_inst);
 818 }
 819
 820 static struct configfs_item_operations f_uac1_item_ops = {
 821         .release        = f_uac1_attr_release,
 822 };
 823
 824 #define UAC1_INT_ATTRIBUTE(name)                                        \
 825 static ssize_t f_uac1_opts_##name##_show(struct config_item *item,      \
 826                                          char *page)                    \
 827 {                                                                       \
 828         struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 829         int result;                                                     \
 830                                                                         \
 831         mutex_lock(&opts->lock);                                        \
 832         result = sprintf(page, "%u\n", opts->name);                     \
 833         mutex_unlock(&opts->lock);                                      \
 834                                                                         \
 835         return result;                                                  \
 836 }                                                                       \
 837                                                                         \
 838 static ssize_t f_uac1_opts_##name##_store(struct config_item *item,             \
 839                                           const char *page, size_t len) \
 840 {                                                                       \
 841         struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 842         int ret;                                                        \
 843         u32 num;                                                        \
 844                                                                         \
 845         mutex_lock(&opts->lock);                                        \
 846         if (opts->refcnt) {                                             \
 847                 ret = -EBUSY;                                           \
 848                 goto end;                                               \
 849         }                                                               \
 850                                                                         \
 851         ret = kstrtou32(page, 0, &num);                                 \
 852         if (ret)                                                        \
 853                 goto end;                                               \
 854                                                                         \
 855         opts->name = num;                                               \
 856         ret = len;                                                      \
 857                                                                         \
 858 end:                                                                    \
 859         mutex_unlock(&opts->lock);                                      \
 860         return ret;                                                     \
 861 }                                                                       \
 862                                                                         \
 863 CONFIGFS_ATTR(f_uac1_opts_, name)
 864
 865 UAC1_INT_ATTRIBUTE(req_buf_size);
 866 UAC1_INT_ATTRIBUTE(req_count);
 867 UAC1_INT_ATTRIBUTE(audio_buf_size);
 868
 869 #define UAC1_STR_ATTRIBUTE(name)                                        \
 870 static ssize_t f_uac1_opts_##name##_show(struct config_item *item,      \
 871                                          char *page)                    \
 872 {                                                                       \
 873         struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 874         int result;                                                     \
 875                                                                         \
 876         mutex_lock(&opts->lock);                                        \
 877         result = sprintf(page, "%s\n", opts->name);                     \
 878         mutex_unlock(&opts->lock);                                      \
 879                                                                         \
 880         return result;                                                  \
 881 }                                                                       \
 882                                                                         \
 883 static ssize_t f_uac1_opts_##name##_store(struct config_item *item,     \
 884                                           const char *page, size_t len) \
 885 {                                                                       \
 886         struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 887         int ret = -EBUSY;                                               \
 888         char *tmp;                                                      \
 889                                                                         \
 890         mutex_lock(&opts->lock);                                        \
 891         if (opts->refcnt)                                               \
 892                 goto end;                                               \
 893                                                                         \
 894         tmp = kstrndup(page, len, GFP_KERNEL);                          \
 895         if (tmp) {                                                      \
 896                 ret = -ENOMEM;                                          \
 897                 goto end;                                               \
 898         }                                                               \
 899         if (opts->name##_alloc)                                         \
 900                 kfree(opts->name);                                      \
 901         opts->name##_alloc = true;                                      \
 902         opts->name = tmp;                                               \
 903         ret = len;                                                      \
 904                                                                         \
 905 end:                                                                    \
 906         mutex_unlock(&opts->lock);                                      \
 907         return ret;                                                     \
 908 }                                                                       \
 909                                                                         \
 910 CONFIGFS_ATTR(f_uac1_opts_, name)
 911
 912 UAC1_STR_ATTRIBUTE(fn_play);
 913 UAC1_STR_ATTRIBUTE(fn_cap);
 914 UAC1_STR_ATTRIBUTE(fn_cntl);
 915
 916 static struct configfs_attribute *f_uac1_attrs[] = {
 917         &f_uac1_opts_attr_req_buf_size,
 918         &f_uac1_opts_attr_req_count,
 919         &f_uac1_opts_attr_audio_buf_size,
 920         &f_uac1_opts_attr_fn_play,
 921         &f_uac1_opts_attr_fn_cap,
 922         &f_uac1_opts_attr_fn_cntl,
 923         NULL,
 924 };
 925
 926 static struct config_item_type f_uac1_func_type = {
 927         .ct_item_ops    = &f_uac1_item_ops,
 928         .ct_attrs       = f_uac1_attrs,
 929         .ct_owner       = THIS_MODULE,
 930 };
 931
 932 static void f_audio_free_inst(struct usb_function_instance *f)
 933 {
 934         struct f_uac1_legacy_opts *opts;
 935
 936         opts = container_of(f, struct f_uac1_legacy_opts, func_inst);
 937         if (opts->fn_play_alloc)
 938                 kfree(opts->fn_play);
 939         if (opts->fn_cap_alloc)
 940                 kfree(opts->fn_cap);
 941         if (opts->fn_cntl_alloc)
 942                 kfree(opts->fn_cntl);
 943         kfree(opts);
 944 }
 945
 946 static struct usb_function_instance *f_audio_alloc_inst(void)
 947 {
 948         struct f_uac1_legacy_opts *opts;
 949
 950         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 951         if (!opts)
 952                 return ERR_PTR(-ENOMEM);
 953
 954         mutex_init(&opts->lock);
 955         opts->func_inst.free_func_inst = f_audio_free_inst;
 956
 957         config_group_init_type_name(&opts->func_inst.group, "",
 958                                     &f_uac1_func_type);
 959
 960         opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
 961         opts->req_count = UAC1_REQ_COUNT;
 962         opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
 963         opts->fn_play = FILE_PCM_PLAYBACK;
 964         opts->fn_cap = FILE_PCM_CAPTURE;
 965         opts->fn_cntl = FILE_CONTROL;
 966         return &opts->func_inst;
 967 }
 968
 969 static void f_audio_free(struct usb_function *f)
 970 {
 971         struct f_audio *audio = func_to_audio(f);
 972         struct f_uac1_legacy_opts *opts;
 973
 974         gaudio_cleanup(&audio->card);
 975         opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
 976         kfree(audio);
 977         mutex_lock(&opts->lock);
 978         --opts->refcnt;
 979         mutex_unlock(&opts->lock);
 980 }
 981
 982 static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 983 {
 984         usb_free_all_descriptors(f);
 985 }
 986
 987 static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
 988 {
 989         struct f_audio *audio;
 990         struct f_uac1_legacy_opts *opts;
 991
 992         /* allocate and initialize one new instance */
 993         audio = kzalloc(sizeof(*audio), GFP_KERNEL);
 994         if (!audio)
 995                 return ERR_PTR(-ENOMEM);
 996
 997         audio->card.func.name = "g_audio";
 998
 999         opts = container_of(fi, struct f_uac1_legacy_opts, func_inst);
1000         mutex_lock(&opts->lock);
1001         ++opts->refcnt;
1002         mutex_unlock(&opts->lock);
1003         INIT_LIST_HEAD(&audio->play_queue);
1004         spin_lock_init(&audio->lock);
1005
1006         audio->card.func.bind = f_audio_bind;
1007         audio->card.func.unbind = f_audio_unbind;
1008         audio->card.func.set_alt = f_audio_set_alt;
1009         audio->card.func.get_alt = f_audio_get_alt;
1010         audio->card.func.setup = f_audio_setup;
1011         audio->card.func.disable = f_audio_disable;
1012         audio->card.func.free_func = f_audio_free;
1013
1014         control_selector_init(audio);
1015
1016         INIT_WORK(&audio->playback_work, f_audio_playback_work);
1017
1018         return &audio->card.func;
1019 }
1020
1021 DECLARE_USB_FUNCTION_INIT(uac1_legacy, f_audio_alloc_inst, f_audio_alloc);
1022 MODULE_LICENSE("GPL");
1023 MODULE_AUTHOR("Bryan Wu");