drivers/usb/gadget/f_uac2.c

   1 /*
   2  * f_uac2.c -- USB Audio Class 2.0 Function
   3  *
   4  * Copyright (C) 2011
   5  *    Yadwinder Singh (yadi.brar01@gmail.com)
   6  *    Jaswinder Singh (jaswinder.singh@linaro.org)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #include <linux/usb/audio.h>
  15 #include <linux/usb/audio-v2.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/module.h>
  18
  19 #include <sound/core.h>
  20 #include <sound/pcm.h>
  21 #include <sound/pcm_params.h>
  22
  23 /* Playback(USB-IN) Default Stereo - Fl/Fr */
  24 static int p_chmask = 0x3;
  25 module_param(p_chmask, uint, S_IRUGO);
  26 MODULE_PARM_DESC(p_chmask, "Playback Channel Mask");
  27
  28 /* Playback Default 48 KHz */
  29 static int p_srate = 48000;
  30 module_param(p_srate, uint, S_IRUGO);
  31 MODULE_PARM_DESC(p_srate, "Playback Sampling Rate");
  32
  33 /* Playback Default 16bits/sample */
  34 static int p_ssize = 2;
  35 module_param(p_ssize, uint, S_IRUGO);
  36 MODULE_PARM_DESC(p_ssize, "Playback Sample Size(bytes)");
  37
  38 /* Capture(USB-OUT) Default Stereo - Fl/Fr */
  39 static int c_chmask = 0x3;
  40 module_param(c_chmask, uint, S_IRUGO);
  41 MODULE_PARM_DESC(c_chmask, "Capture Channel Mask");
  42
  43 /* Capture Default 64 KHz */
  44 static int c_srate = 64000;
  45 module_param(c_srate, uint, S_IRUGO);
  46 MODULE_PARM_DESC(c_srate, "Capture Sampling Rate");
  47
  48 /* Capture Default 16bits/sample */
  49 static int c_ssize = 2;
  50 module_param(c_ssize, uint, S_IRUGO);
  51 MODULE_PARM_DESC(c_ssize, "Capture Sample Size(bytes)");
  52
  53 /* Keep everyone on toes */
  54 #define USB_XFERS       2
  55
  56 /*
  57  * The driver implements a simple UAC_2 topology.
  58  * USB-OUT -> IT_1 -> OT_3 -> ALSA_Capture
  59  * ALSA_Playback -> IT_2 -> OT_4 -> USB-IN
  60  * Capture and Playback sampling rates are independently
  61  *  controlled by two clock sources :
  62  *    CLK_5 := c_srate, and CLK_6 := p_srate
  63  */
  64 #define USB_OUT_IT_ID   1
  65 #define IO_IN_IT_ID     2
  66 #define IO_OUT_OT_ID    3
  67 #define USB_IN_OT_ID    4
  68 #define USB_OUT_CLK_ID  5
  69 #define USB_IN_CLK_ID   6
  70
  71 #define CONTROL_ABSENT  0
  72 #define CONTROL_RDONLY  1
  73 #define CONTROL_RDWR    3
  74
  75 #define CLK_FREQ_CTRL   0
  76 #define CLK_VLD_CTRL    2
  77
  78 #define COPY_CTRL       0
  79 #define CONN_CTRL       2
  80 #define OVRLD_CTRL      4
  81 #define CLSTR_CTRL      6
  82 #define UNFLW_CTRL      8
  83 #define OVFLW_CTRL      10
  84
  85 const char *uac2_name = "snd_uac2";
  86
  87 struct uac2_req {
  88         struct uac2_rtd_params *pp; /* parent param */
  89         struct usb_request *req;
  90 };
  91
  92 struct uac2_rtd_params {
  93         struct snd_uac2_chip *uac2; /* parent chip */
  94         bool ep_enabled; /* if the ep is enabled */
  95         /* Size of the ring buffer */
  96         size_t dma_bytes;
  97         unsigned char *dma_area;
  98
  99         struct snd_pcm_substream *ss;
 100
 101         /* Ring buffer */
 102         ssize_t hw_ptr;
 103
 104         void *rbuf;
 105
 106         size_t period_size;
 107
 108         unsigned max_psize;
 109         struct uac2_req ureq[USB_XFERS];
 110
 111         spinlock_t lock;
 112 };
 113
 114 struct snd_uac2_chip {
 115         struct platform_device pdev;
 116         struct platform_driver pdrv;
 117
 118         struct uac2_rtd_params p_prm;
 119         struct uac2_rtd_params c_prm;
 120
 121         struct snd_card *card;
 122         struct snd_pcm *pcm;
 123 };
 124
 125 #define BUFF_SIZE_MAX   (PAGE_SIZE * 16)
 126 #define PRD_SIZE_MAX    PAGE_SIZE
 127 #define MIN_PERIODS     4
 128
 129 static struct snd_pcm_hardware uac2_pcm_hardware = {
 130         .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER
 131                  | SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
 132                  | SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
 133         .rates = SNDRV_PCM_RATE_CONTINUOUS,
 134         .periods_max = BUFF_SIZE_MAX / PRD_SIZE_MAX,
 135         .buffer_bytes_max = BUFF_SIZE_MAX,
 136         .period_bytes_max = PRD_SIZE_MAX,
 137         .periods_min = MIN_PERIODS,
 138 };
 139
 140 struct audio_dev {
 141         u8 ac_intf, ac_alt;
 142         u8 as_out_intf, as_out_alt;
 143         u8 as_in_intf, as_in_alt;
 144
 145         struct usb_ep *in_ep, *out_ep;
 146         struct usb_function func;
 147
 148         /* The ALSA Sound Card it represents on the USB-Client side */
 149         struct snd_uac2_chip uac2;
 150 };
 151
 152 static struct audio_dev *agdev_g;
 153
 154 static inline
 155 struct audio_dev *func_to_agdev(struct usb_function *f)
 156 {
 157         return container_of(f, struct audio_dev, func);
 158 }
 159
 160 static inline
 161 struct audio_dev *uac2_to_agdev(struct snd_uac2_chip *u)
 162 {
 163         return container_of(u, struct audio_dev, uac2);
 164 }
 165
 166 static inline
 167 struct snd_uac2_chip *pdev_to_uac2(struct platform_device *p)
 168 {
 169         return container_of(p, struct snd_uac2_chip, pdev);
 170 }
 171
 172 static inline
 173 uint num_channels(uint chanmask)
 174 {
 175         uint num = 0;
 176
 177         while (chanmask) {
 178                 num += (chanmask & 1);
 179                 chanmask >>= 1;
 180         }
 181
 182         return num;
 183 }
 184
 185 static void
 186 agdev_iso_complete(struct usb_ep *ep, struct usb_request *req)
 187 {
 188         unsigned pending;
 189         unsigned long flags;
 190         bool update_alsa = false;
 191         unsigned char *src, *dst;
 192         int status = req->status;
 193         struct uac2_req *ur = req->context;
 194         struct snd_pcm_substream *substream;
 195         struct uac2_rtd_params *prm = ur->pp;
 196         struct snd_uac2_chip *uac2 = prm->uac2;
 197
 198         /* i/f shutting down */
 199         if (!prm->ep_enabled)
 200                 return;
 201
 202         /*
 203          * We can't really do much about bad xfers.
 204          * Afterall, the ISOCH xfers could fail legitimately.
 205          */
 206         if (status)
 207                 pr_debug("%s: iso_complete status(%d) %d/%d\n",
 208                         __func__, status, req->actual, req->length);
 209
 210         substream = prm->ss;
 211
 212         /* Do nothing if ALSA isn't active */
 213         if (!substream)
 214                 goto exit;
 215
 216         spin_lock_irqsave(&prm->lock, flags);
 217
 218         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 219                 src = prm->dma_area + prm->hw_ptr;
 220                 req->actual = req->length;
 221                 dst = req->buf;
 222         } else {
 223                 dst = prm->dma_area + prm->hw_ptr;
 224                 src = req->buf;
 225         }
 226
 227         pending = prm->hw_ptr % prm->period_size;
 228         pending += req->actual;
 229         if (pending >= prm->period_size)
 230                 update_alsa = true;
 231
 232         prm->hw_ptr = (prm->hw_ptr + req->actual) % prm->dma_bytes;
 233
 234         spin_unlock_irqrestore(&prm->lock, flags);
 235
 236         /* Pack USB load in ALSA ring buffer */
 237         memcpy(dst, src, req->actual);
 238 exit:
 239         if (usb_ep_queue(ep, req, GFP_ATOMIC))
 240                 dev_err(&uac2->pdev.dev, "%d Error!\n", __LINE__);
 241
 242         if (update_alsa)
 243                 snd_pcm_period_elapsed(substream);
 244
 245         return;
 246 }
 247
 248 static int
 249 uac2_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 250 {
 251         struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
 252         struct uac2_rtd_params *prm;
 253         unsigned long flags;
 254         int err = 0;
 255
 256         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 257                 prm = &uac2->p_prm;
 258         else
 259                 prm = &uac2->c_prm;
 260
 261         spin_lock_irqsave(&prm->lock, flags);
 262
 263         /* Reset */
 264         prm->hw_ptr = 0;
 265
 266         switch (cmd) {
 267         case SNDRV_PCM_TRIGGER_START:
 268         case SNDRV_PCM_TRIGGER_RESUME:
 269                 prm->ss = substream;
 270                 break;
 271         case SNDRV_PCM_TRIGGER_STOP:
 272         case SNDRV_PCM_TRIGGER_SUSPEND:
 273                 prm->ss = NULL;
 274                 break;
 275         default:
 276                 err = -EINVAL;
 277         }
 278
 279         spin_unlock_irqrestore(&prm->lock, flags);
 280
 281         /* Clear buffer after Play stops */
 282         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && !prm->ss)
 283                 memset(prm->rbuf, 0, prm->max_psize * USB_XFERS);
 284
 285         return err;
 286 }
 287
 288 static snd_pcm_uframes_t uac2_pcm_pointer(struct snd_pcm_substream *substream)
 289 {
 290         struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
 291         struct uac2_rtd_params *prm;
 292
 293         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 294                 prm = &uac2->p_prm;
 295         else
 296                 prm = &uac2->c_prm;
 297
 298         return bytes_to_frames(substream->runtime, prm->hw_ptr);
 299 }
 300
 301 static int uac2_pcm_hw_params(struct snd_pcm_substream *substream,
 302                                struct snd_pcm_hw_params *hw_params)
 303 {
 304         struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
 305         struct uac2_rtd_params *prm;
 306         int err;
 307
 308         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 309                 prm = &uac2->p_prm;
 310         else
 311                 prm = &uac2->c_prm;
 312
 313         err = snd_pcm_lib_malloc_pages(substream,
 314                                         params_buffer_bytes(hw_params));
 315         if (err >= 0) {
 316                 prm->dma_bytes = substream->runtime->dma_bytes;
 317                 prm->dma_area = substream->runtime->dma_area;
 318                 prm->period_size = params_period_bytes(hw_params);
 319         }
 320
 321         return err;
 322 }
 323
 324 static int uac2_pcm_hw_free(struct snd_pcm_substream *substream)
 325 {
 326         struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
 327         struct uac2_rtd_params *prm;
 328
 329         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 330                 prm = &uac2->p_prm;
 331         else
 332                 prm = &uac2->c_prm;
 333
 334         prm->dma_area = NULL;
 335         prm->dma_bytes = 0;
 336         prm->period_size = 0;
 337
 338         return snd_pcm_lib_free_pages(substream);
 339 }
 340
 341 static int uac2_pcm_open(struct snd_pcm_substream *substream)
 342 {
 343         struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
 344         struct snd_pcm_runtime *runtime = substream->runtime;
 345
 346         runtime->hw = uac2_pcm_hardware;
 347
 348         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 349                 spin_lock_init(&uac2->p_prm.lock);
 350                 runtime->hw.rate_min = p_srate;
 351                 runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE; /* ! p_ssize ! */
 352                 runtime->hw.channels_min = num_channels(p_chmask);
 353                 runtime->hw.period_bytes_min = 2 * uac2->p_prm.max_psize
 354                                                 / runtime->hw.periods_min;
 355         } else {
 356                 spin_lock_init(&uac2->c_prm.lock);
 357                 runtime->hw.rate_min = c_srate;
 358                 runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE; /* ! c_ssize ! */
 359                 runtime->hw.channels_min = num_channels(c_chmask);
 360                 runtime->hw.period_bytes_min = 2 * uac2->c_prm.max_psize
 361                                                 / runtime->hw.periods_min;
 362         }
 363
 364         runtime->hw.rate_max = runtime->hw.rate_min;
 365         runtime->hw.channels_max = runtime->hw.channels_min;
 366
 367         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 368
 369         return 0;
 370 }
 371
 372 /* ALSA cries without these function pointers */
 373 static int uac2_pcm_null(struct snd_pcm_substream *substream)
 374 {
 375         return 0;
 376 }
 377
 378 static struct snd_pcm_ops uac2_pcm_ops = {
 379         .open = uac2_pcm_open,
 380         .close = uac2_pcm_null,
 381         .ioctl = snd_pcm_lib_ioctl,
 382         .hw_params = uac2_pcm_hw_params,
 383         .hw_free = uac2_pcm_hw_free,
 384         .trigger = uac2_pcm_trigger,
 385         .pointer = uac2_pcm_pointer,
 386         .prepare = uac2_pcm_null,
 387 };
 388
 389 static int snd_uac2_probe(struct platform_device *pdev)
 390 {
 391         struct snd_uac2_chip *uac2 = pdev_to_uac2(pdev);
 392         struct snd_card *card;
 393         struct snd_pcm *pcm;
 394         int err;
 395
 396         /* Choose any slot, with no id */
 397         err = snd_card_create(-1, NULL, THIS_MODULE, 0, &card);
 398         if (err < 0)
 399                 return err;
 400
 401         uac2->card = card;
 402
 403         /*
 404          * Create first PCM device
 405          * Create a substream only for non-zero channel streams
 406          */
 407         err = snd_pcm_new(uac2->card, "UAC2 PCM", 0,
 408                                p_chmask ? 1 : 0, c_chmask ? 1 : 0, &pcm);
 409         if (err < 0)
 410                 goto snd_fail;
 411
 412         strcpy(pcm->name, "UAC2 PCM");
 413         pcm->private_data = uac2;
 414
 415         uac2->pcm = pcm;
 416
 417         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac2_pcm_ops);
 418         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac2_pcm_ops);
 419
 420         strcpy(card->driver, "UAC2_Gadget");
 421         strcpy(card->shortname, "UAC2_Gadget");
 422         sprintf(card->longname, "UAC2_Gadget %i", pdev->id);
 423
 424         snd_card_set_dev(card, &pdev->dev);
 425
 426         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
 427                 snd_dma_continuous_data(GFP_KERNEL), 0, BUFF_SIZE_MAX);
 428
 429         err = snd_card_register(card);
 430         if (!err) {
 431                 platform_set_drvdata(pdev, card);
 432                 return 0;
 433         }
 434
 435 snd_fail:
 436         snd_card_free(card);
 437
 438         uac2->pcm = NULL;
 439         uac2->card = NULL;
 440
 441         return err;
 442 }
 443
 444 static int snd_uac2_remove(struct platform_device *pdev)
 445 {
 446         struct snd_card *card = platform_get_drvdata(pdev);
 447
 448         if (card)
 449                 return snd_card_free(card);
 450
 451         return 0;
 452 }
 453
 454 static int alsa_uac2_init(struct audio_dev *agdev)
 455 {
 456         struct snd_uac2_chip *uac2 = &agdev->uac2;
 457         int err;
 458
 459         uac2->pdrv.probe = snd_uac2_probe;
 460         uac2->pdrv.remove = snd_uac2_remove;
 461         uac2->pdrv.driver.name = uac2_name;
 462
 463         uac2->pdev.id = 0;
 464         uac2->pdev.name = uac2_name;
 465
 466         /* Register snd_uac2 driver */
 467         err = platform_driver_register(&uac2->pdrv);
 468         if (err)
 469                 return err;
 470
 471         /* Register snd_uac2 device */
 472         err = platform_device_register(&uac2->pdev);
 473         if (err)
 474                 platform_driver_unregister(&uac2->pdrv);
 475
 476         return err;
 477 }
 478
 479 static void alsa_uac2_exit(struct audio_dev *agdev)
 480 {
 481         struct snd_uac2_chip *uac2 = &agdev->uac2;
 482
 483         platform_driver_unregister(&uac2->pdrv);
 484         platform_device_unregister(&uac2->pdev);
 485 }
 486
 487
 488 /* --------- USB Function Interface ------------- */
 489
 490 enum {
 491         STR_ASSOC,
 492         STR_IF_CTRL,
 493         STR_CLKSRC_IN,
 494         STR_CLKSRC_OUT,
 495         STR_USB_IT,
 496         STR_IO_IT,
 497         STR_USB_OT,
 498         STR_IO_OT,
 499         STR_AS_OUT_ALT0,
 500         STR_AS_OUT_ALT1,
 501         STR_AS_IN_ALT0,
 502         STR_AS_IN_ALT1,
 503 };
 504
 505 static char clksrc_in[8];
 506 static char clksrc_out[8];
 507
 508 static struct usb_string strings_fn[] = {
 509         [STR_ASSOC].s = "Source/Sink",
 510         [STR_IF_CTRL].s = "Topology Control",
 511         [STR_CLKSRC_IN].s = clksrc_in,
 512         [STR_CLKSRC_OUT].s = clksrc_out,
 513         [STR_USB_IT].s = "USBH Out",
 514         [STR_IO_IT].s = "USBD Out",
 515         [STR_USB_OT].s = "USBH In",
 516         [STR_IO_OT].s = "USBD In",
 517         [STR_AS_OUT_ALT0].s = "Playback Inactive",
 518         [STR_AS_OUT_ALT1].s = "Playback Active",
 519         [STR_AS_IN_ALT0].s = "Capture Inactive",
 520         [STR_AS_IN_ALT1].s = "Capture Active",
 521         { },
 522 };
 523
 524 static struct usb_gadget_strings str_fn = {
 525         .language = 0x0409,     /* en-us */
 526         .strings = strings_fn,
 527 };
 528
 529 static struct usb_gadget_strings *fn_strings[] = {
 530         &str_fn,
 531         NULL,
 532 };
 533
 534 static struct usb_qualifier_descriptor devqual_desc = {
 535         .bLength = sizeof devqual_desc,
 536         .bDescriptorType = USB_DT_DEVICE_QUALIFIER,
 537
 538         .bcdUSB = cpu_to_le16(0x200),
 539         .bDeviceClass = USB_CLASS_MISC,
 540         .bDeviceSubClass = 0x02,
 541         .bDeviceProtocol = 0x01,
 542         .bNumConfigurations = 1,
 543         .bRESERVED = 0,
 544 };
 545
 546 static struct usb_interface_assoc_descriptor iad_desc = {
 547         .bLength = sizeof iad_desc,
 548         .bDescriptorType = USB_DT_INTERFACE_ASSOCIATION,
 549
 550         .bFirstInterface = 0,
 551         .bInterfaceCount = 3,
 552         .bFunctionClass = USB_CLASS_AUDIO,
 553         .bFunctionSubClass = UAC2_FUNCTION_SUBCLASS_UNDEFINED,
 554         .bFunctionProtocol = UAC_VERSION_2,
 555 };
 556
 557 /* Audio Control Interface */
 558 static struct usb_interface_descriptor std_ac_if_desc = {
 559         .bLength = sizeof std_ac_if_desc,
 560         .bDescriptorType = USB_DT_INTERFACE,
 561
 562         .bAlternateSetting = 0,
 563         .bNumEndpoints = 0,
 564         .bInterfaceClass = USB_CLASS_AUDIO,
 565         .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL,
 566         .bInterfaceProtocol = UAC_VERSION_2,
 567 };
 568
 569 /* Clock source for IN traffic */
 570 struct uac_clock_source_descriptor in_clk_src_desc = {
 571         .bLength = sizeof in_clk_src_desc,
 572         .bDescriptorType = USB_DT_CS_INTERFACE,
 573
 574         .bDescriptorSubtype = UAC2_CLOCK_SOURCE,
 575         .bClockID = USB_IN_CLK_ID,
 576         .bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
 577         .bmControls = (CONTROL_RDONLY << CLK_FREQ_CTRL),
 578         .bAssocTerminal = 0,
 579 };
 580
 581 /* Clock source for OUT traffic */
 582 struct uac_clock_source_descriptor out_clk_src_desc = {
 583         .bLength = sizeof out_clk_src_desc,
 584         .bDescriptorType = USB_DT_CS_INTERFACE,
 585
 586         .bDescriptorSubtype = UAC2_CLOCK_SOURCE,
 587         .bClockID = USB_OUT_CLK_ID,
 588         .bmAttributes = UAC_CLOCK_SOURCE_TYPE_INT_FIXED,
 589         .bmControls = (CONTROL_RDONLY << CLK_FREQ_CTRL),
 590         .bAssocTerminal = 0,
 591 };
 592
 593 /* Input Terminal for USB_OUT */
 594 struct uac2_input_terminal_descriptor usb_out_it_desc = {
 595         .bLength = sizeof usb_out_it_desc,
 596         .bDescriptorType = USB_DT_CS_INTERFACE,
 597
 598         .bDescriptorSubtype = UAC_INPUT_TERMINAL,
 599         .bTerminalID = USB_OUT_IT_ID,
 600         .wTerminalType = cpu_to_le16(UAC_TERMINAL_STREAMING),
 601         .bAssocTerminal = 0,
 602         .bCSourceID = USB_OUT_CLK_ID,
 603         .iChannelNames = 0,
 604         .bmControls = (CONTROL_RDWR << COPY_CTRL),
 605 };
 606
 607 /* Input Terminal for I/O-In */
 608 struct uac2_input_terminal_descriptor io_in_it_desc = {
 609         .bLength = sizeof io_in_it_desc,
 610         .bDescriptorType = USB_DT_CS_INTERFACE,
 611
 612         .bDescriptorSubtype = UAC_INPUT_TERMINAL,
 613         .bTerminalID = IO_IN_IT_ID,
 614         .wTerminalType = cpu_to_le16(UAC_INPUT_TERMINAL_UNDEFINED),
 615         .bAssocTerminal = 0,
 616         .bCSourceID = USB_IN_CLK_ID,
 617         .iChannelNames = 0,
 618         .bmControls = (CONTROL_RDWR << COPY_CTRL),
 619 };
 620
 621 /* Ouput Terminal for USB_IN */
 622 struct uac2_output_terminal_descriptor usb_in_ot_desc = {
 623         .bLength = sizeof usb_in_ot_desc,
 624         .bDescriptorType = USB_DT_CS_INTERFACE,
 625
 626         .bDescriptorSubtype = UAC_OUTPUT_TERMINAL,
 627         .bTerminalID = USB_IN_OT_ID,
 628         .wTerminalType = cpu_to_le16(UAC_TERMINAL_STREAMING),
 629         .bAssocTerminal = 0,
 630         .bSourceID = IO_IN_IT_ID,
 631         .bCSourceID = USB_IN_CLK_ID,
 632         .bmControls = (CONTROL_RDWR << COPY_CTRL),
 633 };
 634
 635 /* Ouput Terminal for I/O-Out */
 636 struct uac2_output_terminal_descriptor io_out_ot_desc = {
 637         .bLength = sizeof io_out_ot_desc,
 638         .bDescriptorType = USB_DT_CS_INTERFACE,
 639
 640         .bDescriptorSubtype = UAC_OUTPUT_TERMINAL,
 641         .bTerminalID = IO_OUT_OT_ID,
 642         .wTerminalType = cpu_to_le16(UAC_OUTPUT_TERMINAL_UNDEFINED),
 643         .bAssocTerminal = 0,
 644         .bSourceID = USB_OUT_IT_ID,
 645         .bCSourceID = USB_OUT_CLK_ID,
 646         .bmControls = (CONTROL_RDWR << COPY_CTRL),
 647 };
 648
 649 struct uac2_ac_header_descriptor ac_hdr_desc = {
 650         .bLength = sizeof ac_hdr_desc,
 651         .bDescriptorType = USB_DT_CS_INTERFACE,
 652
 653         .bDescriptorSubtype = UAC_MS_HEADER,
 654         .bcdADC = cpu_to_le16(0x200),
 655         .bCategory = UAC2_FUNCTION_IO_BOX,
 656         .wTotalLength = sizeof in_clk_src_desc + sizeof out_clk_src_desc
 657                          + sizeof usb_out_it_desc + sizeof io_in_it_desc
 658                         + sizeof usb_in_ot_desc + sizeof io_out_ot_desc,
 659         .bmControls = 0,
 660 };
 661
 662 /* Audio Streaming OUT Interface - Alt0 */
 663 static struct usb_interface_descriptor std_as_out_if0_desc = {
 664         .bLength = sizeof std_as_out_if0_desc,
 665         .bDescriptorType = USB_DT_INTERFACE,
 666
 667         .bAlternateSetting = 0,
 668         .bNumEndpoints = 0,
 669         .bInterfaceClass = USB_CLASS_AUDIO,
 670         .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
 671         .bInterfaceProtocol = UAC_VERSION_2,
 672 };
 673
 674 /* Audio Streaming OUT Interface - Alt1 */
 675 static struct usb_interface_descriptor std_as_out_if1_desc = {
 676         .bLength = sizeof std_as_out_if1_desc,
 677         .bDescriptorType = USB_DT_INTERFACE,
 678
 679         .bAlternateSetting = 1,
 680         .bNumEndpoints = 1,
 681         .bInterfaceClass = USB_CLASS_AUDIO,
 682         .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
 683         .bInterfaceProtocol = UAC_VERSION_2,
 684 };
 685
 686 /* Audio Stream OUT Intface Desc */
 687 struct uac2_as_header_descriptor as_out_hdr_desc = {
 688         .bLength = sizeof as_out_hdr_desc,
 689         .bDescriptorType = USB_DT_CS_INTERFACE,
 690
 691         .bDescriptorSubtype = UAC_AS_GENERAL,
 692         .bTerminalLink = USB_OUT_IT_ID,
 693         .bmControls = 0,
 694         .bFormatType = UAC_FORMAT_TYPE_I,
 695         .bmFormats = cpu_to_le32(UAC_FORMAT_TYPE_I_PCM),
 696         .iChannelNames = 0,
 697 };
 698
 699 /* Audio USB_OUT Format */
 700 struct uac2_format_type_i_descriptor as_out_fmt1_desc = {
 701         .bLength = sizeof as_out_fmt1_desc,
 702         .bDescriptorType = USB_DT_CS_INTERFACE,
 703         .bDescriptorSubtype = UAC_FORMAT_TYPE,
 704         .bFormatType = UAC_FORMAT_TYPE_I,
 705 };
 706
 707 /* STD AS ISO OUT Endpoint */
 708 struct usb_endpoint_descriptor fs_epout_desc = {
 709         .bLength = USB_DT_ENDPOINT_SIZE,
 710         .bDescriptorType = USB_DT_ENDPOINT,
 711
 712         .bEndpointAddress = USB_DIR_OUT,
 713         .bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
 714         .bInterval = 1,
 715 };
 716
 717 struct usb_endpoint_descriptor hs_epout_desc = {
 718         .bLength = USB_DT_ENDPOINT_SIZE,
 719         .bDescriptorType = USB_DT_ENDPOINT,
 720
 721         .bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
 722         .bInterval = 4,
 723 };
 724
 725 /* CS AS ISO OUT Endpoint */
 726 static struct uac2_iso_endpoint_descriptor as_iso_out_desc = {
 727         .bLength = sizeof as_iso_out_desc,
 728         .bDescriptorType = USB_DT_CS_ENDPOINT,
 729
 730         .bDescriptorSubtype = UAC_EP_GENERAL,
 731         .bmAttributes = 0,
 732         .bmControls = 0,
 733         .bLockDelayUnits = 0,
 734         .wLockDelay = 0,
 735 };
 736
 737 /* Audio Streaming IN Interface - Alt0 */
 738 static struct usb_interface_descriptor std_as_in_if0_desc = {
 739         .bLength = sizeof std_as_in_if0_desc,
 740         .bDescriptorType = USB_DT_INTERFACE,
 741
 742         .bAlternateSetting = 0,
 743         .bNumEndpoints = 0,
 744         .bInterfaceClass = USB_CLASS_AUDIO,
 745         .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
 746         .bInterfaceProtocol = UAC_VERSION_2,
 747 };
 748
 749 /* Audio Streaming IN Interface - Alt1 */
 750 static struct usb_interface_descriptor std_as_in_if1_desc = {
 751         .bLength = sizeof std_as_in_if1_desc,
 752         .bDescriptorType = USB_DT_INTERFACE,
 753
 754         .bAlternateSetting = 1,
 755         .bNumEndpoints = 1,
 756         .bInterfaceClass = USB_CLASS_AUDIO,
 757         .bInterfaceSubClass = USB_SUBCLASS_AUDIOSTREAMING,
 758         .bInterfaceProtocol = UAC_VERSION_2,
 759 };
 760
 761 /* Audio Stream IN Intface Desc */
 762 struct uac2_as_header_descriptor as_in_hdr_desc = {
 763         .bLength = sizeof as_in_hdr_desc,
 764         .bDescriptorType = USB_DT_CS_INTERFACE,
 765
 766         .bDescriptorSubtype = UAC_AS_GENERAL,
 767         .bTerminalLink = USB_IN_OT_ID,
 768         .bmControls = 0,
 769         .bFormatType = UAC_FORMAT_TYPE_I,
 770         .bmFormats = cpu_to_le32(UAC_FORMAT_TYPE_I_PCM),
 771         .iChannelNames = 0,
 772 };
 773
 774 /* Audio USB_IN Format */
 775 struct uac2_format_type_i_descriptor as_in_fmt1_desc = {
 776         .bLength = sizeof as_in_fmt1_desc,
 777         .bDescriptorType = USB_DT_CS_INTERFACE,
 778         .bDescriptorSubtype = UAC_FORMAT_TYPE,
 779         .bFormatType = UAC_FORMAT_TYPE_I,
 780 };
 781
 782 /* STD AS ISO IN Endpoint */
 783 struct usb_endpoint_descriptor fs_epin_desc = {
 784         .bLength = USB_DT_ENDPOINT_SIZE,
 785         .bDescriptorType = USB_DT_ENDPOINT,
 786
 787         .bEndpointAddress = USB_DIR_IN,
 788         .bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
 789         .bInterval = 1,
 790 };
 791
 792 struct usb_endpoint_descriptor hs_epin_desc = {
 793         .bLength = USB_DT_ENDPOINT_SIZE,
 794         .bDescriptorType = USB_DT_ENDPOINT,
 795
 796         .bmAttributes = USB_ENDPOINT_XFER_ISOC | USB_ENDPOINT_SYNC_ASYNC,
 797         .bInterval = 4,
 798 };
 799
 800 /* CS AS ISO IN Endpoint */
 801 static struct uac2_iso_endpoint_descriptor as_iso_in_desc = {
 802         .bLength = sizeof as_iso_in_desc,
 803         .bDescriptorType = USB_DT_CS_ENDPOINT,
 804
 805         .bDescriptorSubtype = UAC_EP_GENERAL,
 806         .bmAttributes = 0,
 807         .bmControls = 0,
 808         .bLockDelayUnits = 0,
 809         .wLockDelay = 0,
 810 };
 811
 812 static struct usb_descriptor_header *fs_audio_desc[] = {
 813         (struct usb_descriptor_header *)&iad_desc,
 814         (struct usb_descriptor_header *)&std_ac_if_desc,
 815
 816         (struct usb_descriptor_header *)&ac_hdr_desc,
 817         (struct usb_descriptor_header *)&in_clk_src_desc,
 818         (struct usb_descriptor_header *)&out_clk_src_desc,
 819         (struct usb_descriptor_header *)&usb_out_it_desc,
 820         (struct usb_descriptor_header *)&io_in_it_desc,
 821         (struct usb_descriptor_header *)&usb_in_ot_desc,
 822         (struct usb_descriptor_header *)&io_out_ot_desc,
 823
 824         (struct usb_descriptor_header *)&std_as_out_if0_desc,
 825         (struct usb_descriptor_header *)&std_as_out_if1_desc,
 826
 827         (struct usb_descriptor_header *)&as_out_hdr_desc,
 828         (struct usb_descriptor_header *)&as_out_fmt1_desc,
 829         (struct usb_descriptor_header *)&fs_epout_desc,
 830         (struct usb_descriptor_header *)&as_iso_out_desc,
 831
 832         (struct usb_descriptor_header *)&std_as_in_if0_desc,
 833         (struct usb_descriptor_header *)&std_as_in_if1_desc,
 834
 835         (struct usb_descriptor_header *)&as_in_hdr_desc,
 836         (struct usb_descriptor_header *)&as_in_fmt1_desc,
 837         (struct usb_descriptor_header *)&fs_epin_desc,
 838         (struct usb_descriptor_header *)&as_iso_in_desc,
 839         NULL,
 840 };
 841
 842 static struct usb_descriptor_header *hs_audio_desc[] = {
 843         (struct usb_descriptor_header *)&iad_desc,
 844         (struct usb_descriptor_header *)&std_ac_if_desc,
 845
 846         (struct usb_descriptor_header *)&ac_hdr_desc,
 847         (struct usb_descriptor_header *)&in_clk_src_desc,
 848         (struct usb_descriptor_header *)&out_clk_src_desc,
 849         (struct usb_descriptor_header *)&usb_out_it_desc,
 850         (struct usb_descriptor_header *)&io_in_it_desc,
 851         (struct usb_descriptor_header *)&usb_in_ot_desc,
 852         (struct usb_descriptor_header *)&io_out_ot_desc,
 853
 854         (struct usb_descriptor_header *)&std_as_out_if0_desc,
 855         (struct usb_descriptor_header *)&std_as_out_if1_desc,
 856
 857         (struct usb_descriptor_header *)&as_out_hdr_desc,
 858         (struct usb_descriptor_header *)&as_out_fmt1_desc,
 859         (struct usb_descriptor_header *)&hs_epout_desc,
 860         (struct usb_descriptor_header *)&as_iso_out_desc,
 861
 862         (struct usb_descriptor_header *)&std_as_in_if0_desc,
 863         (struct usb_descriptor_header *)&std_as_in_if1_desc,
 864
 865         (struct usb_descriptor_header *)&as_in_hdr_desc,
 866         (struct usb_descriptor_header *)&as_in_fmt1_desc,
 867         (struct usb_descriptor_header *)&hs_epin_desc,
 868         (struct usb_descriptor_header *)&as_iso_in_desc,
 869         NULL,
 870 };
 871
 872 struct cntrl_cur_lay3 {
 873         __u32   dCUR;
 874 };
 875
 876 struct cntrl_range_lay3 {
 877         __u16   wNumSubRanges;
 878         __u32   dMIN;
 879         __u32   dMAX;
 880         __u32   dRES;
 881 } __packed;
 882
 883 static inline void
 884 free_ep(struct uac2_rtd_params *prm, struct usb_ep *ep)
 885 {
 886         struct snd_uac2_chip *uac2 = prm->uac2;
 887         int i;
 888
 889         prm->ep_enabled = false;
 890
 891         for (i = 0; i < USB_XFERS; i++) {
 892                 if (prm->ureq[i].req) {
 893                         usb_ep_dequeue(ep, prm->ureq[i].req);
 894                         usb_ep_free_request(ep, prm->ureq[i].req);
 895                         prm->ureq[i].req = NULL;
 896                 }
 897         }
 898
 899         if (usb_ep_disable(ep))
 900                 dev_err(&uac2->pdev.dev,
 901                         "%s:%d Error!\n", __func__, __LINE__);
 902 }
 903
 904 static int __init
 905 afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 906 {
 907         struct audio_dev *agdev = func_to_agdev(fn);
 908         struct snd_uac2_chip *uac2 = &agdev->uac2;
 909         struct usb_composite_dev *cdev = cfg->cdev;
 910         struct usb_gadget *gadget = cdev->gadget;
 911         struct uac2_rtd_params *prm;
 912         int ret;
 913
 914         ret = usb_interface_id(cfg, fn);
 915         if (ret < 0) {
 916                 dev_err(&uac2->pdev.dev,
 917                         "%s:%d Error!\n", __func__, __LINE__);
 918                 return ret;
 919         }
 920         std_ac_if_desc.bInterfaceNumber = ret;
 921         agdev->ac_intf = ret;
 922         agdev->ac_alt = 0;
 923
 924         ret = usb_interface_id(cfg, fn);
 925         if (ret < 0) {
 926                 dev_err(&uac2->pdev.dev,
 927                         "%s:%d Error!\n", __func__, __LINE__);
 928                 return ret;
 929         }
 930         std_as_out_if0_desc.bInterfaceNumber = ret;
 931         std_as_out_if1_desc.bInterfaceNumber = ret;
 932         agdev->as_out_intf = ret;
 933         agdev->as_out_alt = 0;
 934
 935         ret = usb_interface_id(cfg, fn);
 936         if (ret < 0) {
 937                 dev_err(&uac2->pdev.dev,
 938                         "%s:%d Error!\n", __func__, __LINE__);
 939                 return ret;
 940         }
 941         std_as_in_if0_desc.bInterfaceNumber = ret;
 942         std_as_in_if1_desc.bInterfaceNumber = ret;
 943         agdev->as_in_intf = ret;
 944         agdev->as_in_alt = 0;
 945
 946         agdev->out_ep = usb_ep_autoconfig(gadget, &fs_epout_desc);
 947         if (!agdev->out_ep) {
 948                 dev_err(&uac2->pdev.dev,
 949                         "%s:%d Error!\n", __func__, __LINE__);
 950                 goto err;
 951         }
 952         agdev->out_ep->driver_data = agdev;
 953
 954         agdev->in_ep = usb_ep_autoconfig(gadget, &fs_epin_desc);
 955         if (!agdev->in_ep) {
 956                 dev_err(&uac2->pdev.dev,
 957                         "%s:%d Error!\n", __func__, __LINE__);
 958                 goto err;
 959         }
 960         agdev->in_ep->driver_data = agdev;
 961
 962         uac2->p_prm.uac2 = uac2;
 963         uac2->c_prm.uac2 = uac2;
 964
 965         hs_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
 966         hs_epout_desc.wMaxPacketSize = fs_epout_desc.wMaxPacketSize;
 967         hs_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
 968         hs_epin_desc.wMaxPacketSize = fs_epin_desc.wMaxPacketSize;
 969
 970         ret = usb_assign_descriptors(fn, fs_audio_desc, hs_audio_desc, NULL);
 971         if (ret)
 972                 goto err;
 973
 974         prm = &agdev->uac2.c_prm;
 975         prm->max_psize = hs_epout_desc.wMaxPacketSize;
 976         prm->rbuf = kzalloc(prm->max_psize * USB_XFERS, GFP_KERNEL);
 977         if (!prm->rbuf) {
 978                 prm->max_psize = 0;
 979                 dev_err(&uac2->pdev.dev,
 980                         "%s:%d Error!\n", __func__, __LINE__);
 981                 goto err;
 982         }
 983
 984         prm = &agdev->uac2.p_prm;
 985         prm->max_psize = hs_epin_desc.wMaxPacketSize;
 986         prm->rbuf = kzalloc(prm->max_psize * USB_XFERS, GFP_KERNEL);
 987         if (!prm->rbuf) {
 988                 prm->max_psize = 0;
 989                 dev_err(&uac2->pdev.dev,
 990                         "%s:%d Error!\n", __func__, __LINE__);
 991                 goto err;
 992         }
 993
 994         ret = alsa_uac2_init(agdev);
 995         if (ret)
 996                 goto err;
 997         return 0;
 998 err:
 999         kfree(agdev->uac2.p_prm.rbuf);
1000         kfree(agdev->uac2.c_prm.rbuf);
1001         usb_free_all_descriptors(fn);
1002         if (agdev->in_ep)
1003                 agdev->in_ep->driver_data = NULL;
1004         if (agdev->out_ep)
1005                 agdev->out_ep->driver_data = NULL;
1006         return -EINVAL;
1007 }
1008
1009 static void
1010 afunc_unbind(struct usb_configuration *cfg, struct usb_function *fn)
1011 {
1012         struct audio_dev *agdev = func_to_agdev(fn);
1013         struct uac2_rtd_params *prm;
1014
1015         alsa_uac2_exit(agdev);
1016
1017         prm = &agdev->uac2.p_prm;
1018         kfree(prm->rbuf);
1019
1020         prm = &agdev->uac2.c_prm;
1021         kfree(prm->rbuf);
1022         usb_free_all_descriptors(fn);
1023
1024         if (agdev->in_ep)
1025                 agdev->in_ep->driver_data = NULL;
1026         if (agdev->out_ep)
1027                 agdev->out_ep->driver_data = NULL;
1028 }
1029
1030 static int
1031 afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
1032 {
1033         struct usb_composite_dev *cdev = fn->config->cdev;
1034         struct audio_dev *agdev = func_to_agdev(fn);
1035         struct snd_uac2_chip *uac2 = &agdev->uac2;
1036         struct usb_gadget *gadget = cdev->gadget;
1037         struct usb_request *req;
1038         struct usb_ep *ep;
1039         struct uac2_rtd_params *prm;
1040         int i;
1041
1042         /* No i/f has more than 2 alt settings */
1043         if (alt > 1) {
1044                 dev_err(&uac2->pdev.dev,
1045                         "%s:%d Error!\n", __func__, __LINE__);
1046                 return -EINVAL;
1047         }
1048
1049         if (intf == agdev->ac_intf) {
1050                 /* Control I/f has only 1 AltSetting - 0 */
1051                 if (alt) {
1052                         dev_err(&uac2->pdev.dev,
1053                                 "%s:%d Error!\n", __func__, __LINE__);
1054                         return -EINVAL;
1055                 }
1056                 return 0;
1057         }
1058
1059         if (intf == agdev->as_out_intf) {
1060                 ep = agdev->out_ep;
1061                 prm = &uac2->c_prm;
1062                 config_ep_by_speed(gadget, fn, ep);
1063                 agdev->as_out_alt = alt;
1064         } else if (intf == agdev->as_in_intf) {
1065                 ep = agdev->in_ep;
1066                 prm = &uac2->p_prm;
1067                 config_ep_by_speed(gadget, fn, ep);
1068                 agdev->as_in_alt = alt;
1069         } else {
1070                 dev_err(&uac2->pdev.dev,
1071                         "%s:%d Error!\n", __func__, __LINE__);
1072                 return -EINVAL;
1073         }
1074
1075         if (alt == 0) {
1076                 free_ep(prm, ep);
1077                 return 0;
1078         }
1079
1080         prm->ep_enabled = true;
1081         usb_ep_enable(ep);
1082
1083         for (i = 0; i < USB_XFERS; i++) {
1084                 if (prm->ureq[i].req) {
1085                         if (usb_ep_queue(ep, prm->ureq[i].req, GFP_ATOMIC))
1086                                 dev_err(&uac2->pdev.dev, "%d Error!\n",
1087                                         __LINE__);
1088                         continue;
1089                 }
1090
1091                 req = usb_ep_alloc_request(ep, GFP_ATOMIC);
1092                 if (req == NULL) {
1093                         dev_err(&uac2->pdev.dev,
1094                                 "%s:%d Error!\n", __func__, __LINE__);
1095                         return -EINVAL;
1096                 }
1097
1098                 prm->ureq[i].req = req;
1099                 prm->ureq[i].pp = prm;
1100
1101                 req->zero = 0;
1102                 req->context = &prm->ureq[i];
1103                 req->length = prm->max_psize;
1104                 req->complete = agdev_iso_complete;
1105                 req->buf = prm->rbuf + i * req->length;
1106
1107                 if (usb_ep_queue(ep, req, GFP_ATOMIC))
1108                         dev_err(&uac2->pdev.dev, "%d Error!\n", __LINE__);
1109         }
1110
1111         return 0;
1112 }
1113
1114 static int
1115 afunc_get_alt(struct usb_function *fn, unsigned intf)
1116 {
1117         struct audio_dev *agdev = func_to_agdev(fn);
1118         struct snd_uac2_chip *uac2 = &agdev->uac2;
1119
1120         if (intf == agdev->ac_intf)
1121                 return agdev->ac_alt;
1122         else if (intf == agdev->as_out_intf)
1123                 return agdev->as_out_alt;
1124         else if (intf == agdev->as_in_intf)
1125                 return agdev->as_in_alt;
1126         else
1127                 dev_err(&uac2->pdev.dev,
1128                         "%s:%d Invalid Interface %d!\n",
1129                         __func__, __LINE__, intf);
1130
1131         return -EINVAL;
1132 }
1133
1134 static void
1135 afunc_disable(struct usb_function *fn)
1136 {
1137         struct audio_dev *agdev = func_to_agdev(fn);
1138         struct snd_uac2_chip *uac2 = &agdev->uac2;
1139
1140         free_ep(&uac2->p_prm, agdev->in_ep);
1141         agdev->as_in_alt = 0;
1142
1143         free_ep(&uac2->c_prm, agdev->out_ep);
1144         agdev->as_out_alt = 0;
1145 }
1146
1147 static int
1148 in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1149 {
1150         struct usb_request *req = fn->config->cdev->req;
1151         struct audio_dev *agdev = func_to_agdev(fn);
1152         struct snd_uac2_chip *uac2 = &agdev->uac2;
1153         u16 w_length = le16_to_cpu(cr->wLength);
1154         u16 w_index = le16_to_cpu(cr->wIndex);
1155         u16 w_value = le16_to_cpu(cr->wValue);
1156         u8 entity_id = (w_index >> 8) & 0xff;
1157         u8 control_selector = w_value >> 8;
1158         int value = -EOPNOTSUPP;
1159
1160         if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
1161                 struct cntrl_cur_lay3 c;
1162
1163                 if (entity_id == USB_IN_CLK_ID)
1164                         c.dCUR = p_srate;
1165                 else if (entity_id == USB_OUT_CLK_ID)
1166                         c.dCUR = c_srate;
1167
1168                 value = min_t(unsigned, w_length, sizeof c);
1169                 memcpy(req->buf, &c, value);
1170         } else if (control_selector == UAC2_CS_CONTROL_CLOCK_VALID) {
1171                 *(u8 *)req->buf = 1;
1172                 value = min_t(unsigned, w_length, 1);
1173         } else {
1174                 dev_err(&uac2->pdev.dev,
1175                         "%s:%d control_selector=%d TODO!\n",
1176                         __func__, __LINE__, control_selector);
1177         }
1178
1179         return value;
1180 }
1181
1182 static int
1183 in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1184 {
1185         struct usb_request *req = fn->config->cdev->req;
1186         struct audio_dev *agdev = func_to_agdev(fn);
1187         struct snd_uac2_chip *uac2 = &agdev->uac2;
1188         u16 w_length = le16_to_cpu(cr->wLength);
1189         u16 w_index = le16_to_cpu(cr->wIndex);
1190         u16 w_value = le16_to_cpu(cr->wValue);
1191         u8 entity_id = (w_index >> 8) & 0xff;
1192         u8 control_selector = w_value >> 8;
1193         struct cntrl_range_lay3 r;
1194         int value = -EOPNOTSUPP;
1195
1196         if (control_selector == UAC2_CS_CONTROL_SAM_FREQ) {
1197                 if (entity_id == USB_IN_CLK_ID)
1198                         r.dMIN = p_srate;
1199                 else if (entity_id == USB_OUT_CLK_ID)
1200                         r.dMIN = c_srate;
1201                 else
1202                         return -EOPNOTSUPP;
1203
1204                 r.dMAX = r.dMIN;
1205                 r.dRES = 0;
1206                 r.wNumSubRanges = 1;
1207
1208                 value = min_t(unsigned, w_length, sizeof r);
1209                 memcpy(req->buf, &r, value);
1210         } else {
1211                 dev_err(&uac2->pdev.dev,
1212                         "%s:%d control_selector=%d TODO!\n",
1213                         __func__, __LINE__, control_selector);
1214         }
1215
1216         return value;
1217 }
1218
1219 static int
1220 ac_rq_in(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1221 {
1222         if (cr->bRequest == UAC2_CS_CUR)
1223                 return in_rq_cur(fn, cr);
1224         else if (cr->bRequest == UAC2_CS_RANGE)
1225                 return in_rq_range(fn, cr);
1226         else
1227                 return -EOPNOTSUPP;
1228 }
1229
1230 static int
1231 out_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1232 {
1233         u16 w_length = le16_to_cpu(cr->wLength);
1234         u16 w_value = le16_to_cpu(cr->wValue);
1235         u8 control_selector = w_value >> 8;
1236
1237         if (control_selector == UAC2_CS_CONTROL_SAM_FREQ)
1238                 return w_length;
1239
1240         return -EOPNOTSUPP;
1241 }
1242
1243 static int
1244 setup_rq_inf(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1245 {
1246         struct audio_dev *agdev = func_to_agdev(fn);
1247         struct snd_uac2_chip *uac2 = &agdev->uac2;
1248         u16 w_index = le16_to_cpu(cr->wIndex);
1249         u8 intf = w_index & 0xff;
1250
1251         if (intf != agdev->ac_intf) {
1252                 dev_err(&uac2->pdev.dev,
1253                         "%s:%d Error!\n", __func__, __LINE__);
1254                 return -EOPNOTSUPP;
1255         }
1256
1257         if (cr->bRequestType & USB_DIR_IN)
1258                 return ac_rq_in(fn, cr);
1259         else if (cr->bRequest == UAC2_CS_CUR)
1260                 return out_rq_cur(fn, cr);
1261
1262         return -EOPNOTSUPP;
1263 }
1264
1265 static int
1266 afunc_setup(struct usb_function *fn, const struct usb_ctrlrequest *cr)
1267 {
1268         struct usb_composite_dev *cdev = fn->config->cdev;
1269         struct audio_dev *agdev = func_to_agdev(fn);
1270         struct snd_uac2_chip *uac2 = &agdev->uac2;
1271         struct usb_request *req = cdev->req;
1272         u16 w_length = le16_to_cpu(cr->wLength);
1273         int value = -EOPNOTSUPP;
1274
1275         /* Only Class specific requests are supposed to reach here */
1276         if ((cr->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
1277                 return -EOPNOTSUPP;
1278
1279         if ((cr->bRequestType & USB_RECIP_MASK) == USB_RECIP_INTERFACE)
1280                 value = setup_rq_inf(fn, cr);
1281         else
1282                 dev_err(&uac2->pdev.dev, "%s:%d Error!\n", __func__, __LINE__);
1283
1284         if (value >= 0) {
1285                 req->length = value;
1286                 req->zero = value < w_length;
1287                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1288                 if (value < 0) {
1289                         dev_err(&uac2->pdev.dev,
1290                                 "%s:%d Error!\n", __func__, __LINE__);
1291                         req->status = 0;
1292                 }
1293         }
1294
1295         return value;
1296 }
1297
1298 static int audio_bind_config(struct usb_configuration *cfg)
1299 {
1300         int res;
1301
1302         agdev_g = kzalloc(sizeof *agdev_g, GFP_KERNEL);
1303         if (agdev_g == NULL) {
1304                 printk(KERN_ERR "Unable to allocate audio gadget\n");
1305                 return -ENOMEM;
1306         }
1307
1308         res = usb_string_ids_tab(cfg->cdev, strings_fn);
1309         if (res)
1310                 return res;
1311         iad_desc.iFunction = strings_fn[STR_ASSOC].id;
1312         std_ac_if_desc.iInterface = strings_fn[STR_IF_CTRL].id;
1313         in_clk_src_desc.iClockSource = strings_fn[STR_CLKSRC_IN].id;
1314         out_clk_src_desc.iClockSource = strings_fn[STR_CLKSRC_OUT].id;
1315         usb_out_it_desc.iTerminal = strings_fn[STR_USB_IT].id;
1316         io_in_it_desc.iTerminal = strings_fn[STR_IO_IT].id;
1317         usb_in_ot_desc.iTerminal = strings_fn[STR_USB_OT].id;
1318         io_out_ot_desc.iTerminal = strings_fn[STR_IO_OT].id;
1319         std_as_out_if0_desc.iInterface = strings_fn[STR_AS_OUT_ALT0].id;
1320         std_as_out_if1_desc.iInterface = strings_fn[STR_AS_OUT_ALT1].id;
1321         std_as_in_if0_desc.iInterface = strings_fn[STR_AS_IN_ALT0].id;
1322         std_as_in_if1_desc.iInterface = strings_fn[STR_AS_IN_ALT1].id;
1323
1324         agdev_g->func.name = "uac2_func";
1325         agdev_g->func.strings = fn_strings;
1326         agdev_g->func.bind = afunc_bind;
1327         agdev_g->func.unbind = afunc_unbind;
1328         agdev_g->func.set_alt = afunc_set_alt;
1329         agdev_g->func.get_alt = afunc_get_alt;
1330         agdev_g->func.disable = afunc_disable;
1331         agdev_g->func.setup = afunc_setup;
1332
1333         /* Initialize the configurable parameters */
1334         usb_out_it_desc.bNrChannels = num_channels(c_chmask);
1335         usb_out_it_desc.bmChannelConfig = cpu_to_le32(c_chmask);
1336         io_in_it_desc.bNrChannels = num_channels(p_chmask);
1337         io_in_it_desc.bmChannelConfig = cpu_to_le32(p_chmask);
1338         as_out_hdr_desc.bNrChannels = num_channels(c_chmask);
1339         as_out_hdr_desc.bmChannelConfig = cpu_to_le32(c_chmask);
1340         as_in_hdr_desc.bNrChannels = num_channels(p_chmask);
1341         as_in_hdr_desc.bmChannelConfig = cpu_to_le32(p_chmask);
1342         as_out_fmt1_desc.bSubslotSize = c_ssize;
1343         as_out_fmt1_desc.bBitResolution = c_ssize * 8;
1344         as_in_fmt1_desc.bSubslotSize = p_ssize;
1345         as_in_fmt1_desc.bBitResolution = p_ssize * 8;
1346
1347         snprintf(clksrc_in, sizeof(clksrc_in), "%uHz", p_srate);
1348         snprintf(clksrc_out, sizeof(clksrc_out), "%uHz", c_srate);
1349
1350         res = usb_add_function(cfg, &agdev_g->func);
1351         if (res < 0)
1352                 kfree(agdev_g);
1353
1354         return res;
1355 }
1356
1357 static void
1358 uac2_unbind_config(struct usb_configuration *cfg)
1359 {
1360         kfree(agdev_g);
1361         agdev_g = NULL;
1362 }