linux/drivers/usb/gadget/function/f_uac1_legacy.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * f_audio.c -- USB Audio class function driver
   4  *
   5 * Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
   6 * Copyright (C) 2008 Analog Devices, Inc
   7 */
   8
   9#include <linux/slab.h>
  10#include <linux/kernel.h>
  11#include <linux/module.h>
  12#include <linux/device.h>
  13#include <linux/atomic.h>
  14
  15#include "u_uac1_legacy.h"
  16
  17static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value);
  18static int generic_get_cmd(struct usb_audio_control *con, u8 cmd);
  19
  20/*
  21 * DESCRIPTORS ... most are static, but strings and full
  22 * configuration descriptors are built on demand.
  23 */
  24
  25/*
  26 * We have two interfaces- AudioControl and AudioStreaming
  27 * TODO: only supcard playback currently
  28 */
  29#define F_AUDIO_AC_INTERFACE    0
  30#define F_AUDIO_AS_INTERFACE    1
  31#define F_AUDIO_NUM_INTERFACES  1
  32
  33/* B.3.1  Standard AC Interface Descriptor */
  34static struct usb_interface_descriptor ac_interface_desc = {
  35        .bLength =              USB_DT_INTERFACE_SIZE,
  36        .bDescriptorType =      USB_DT_INTERFACE,
  37        .bNumEndpoints =        0,
  38        .bInterfaceClass =      USB_CLASS_AUDIO,
  39        .bInterfaceSubClass =   USB_SUBCLASS_AUDIOCONTROL,
  40};
  41
  42/*
  43 * The number of AudioStreaming and MIDIStreaming interfaces
  44 * in the Audio Interface Collection
  45 */
  46DECLARE_UAC_AC_HEADER_DESCRIPTOR(1);
  47
  48#define UAC_DT_AC_HEADER_LENGTH UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
  49/* 1 input terminal, 1 output terminal and 1 feature unit */
  50#define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH + UAC_DT_INPUT_TERMINAL_SIZE \
  51        + UAC_DT_OUTPUT_TERMINAL_SIZE + UAC_DT_FEATURE_UNIT_SIZE(0))
  52/* B.3.2  Class-Specific AC Interface Descriptor */
  53static struct uac1_ac_header_descriptor_1 ac_header_desc = {
  54        .bLength =              UAC_DT_AC_HEADER_LENGTH,
  55        .bDescriptorType =      USB_DT_CS_INTERFACE,
  56        .bDescriptorSubtype =   UAC_HEADER,
  57        .bcdADC =               cpu_to_le16(0x0100),
  58        .wTotalLength =         cpu_to_le16(UAC_DT_TOTAL_LENGTH),
  59        .bInCollection =        F_AUDIO_NUM_INTERFACES,
  60        .baInterfaceNr = {
  61        /* Interface number of the first AudioStream interface */
  62                [0] =           1,
  63        }
  64};
  65
  66#define INPUT_TERMINAL_ID       1
  67static struct uac_input_terminal_descriptor input_terminal_desc = {
  68        .bLength =              UAC_DT_INPUT_TERMINAL_SIZE,
  69        .bDescriptorType =      USB_DT_CS_INTERFACE,
  70        .bDescriptorSubtype =   UAC_INPUT_TERMINAL,
  71        .bTerminalID =          INPUT_TERMINAL_ID,
  72        .wTerminalType =        UAC_TERMINAL_STREAMING,
  73        .bAssocTerminal =       0,
  74        .wChannelConfig =       0x3,
  75};
  76
  77DECLARE_UAC_FEATURE_UNIT_DESCRIPTOR(0);
  78
  79#define FEATURE_UNIT_ID         2
  80static struct uac_feature_unit_descriptor_0 feature_unit_desc = {
  81        .bLength                = UAC_DT_FEATURE_UNIT_SIZE(0),
  82        .bDescriptorType        = USB_DT_CS_INTERFACE,
  83        .bDescriptorSubtype     = UAC_FEATURE_UNIT,
  84        .bUnitID                = FEATURE_UNIT_ID,
  85        .bSourceID              = INPUT_TERMINAL_ID,
  86        .bControlSize           = 2,
  87        .bmaControls[0]         = (UAC_FU_MUTE | UAC_FU_VOLUME),
  88};
  89
  90static struct usb_audio_control mute_control = {
  91        .list = LIST_HEAD_INIT(mute_control.list),
  92        .name = "Mute Control",
  93        .type = UAC_FU_MUTE,
  94        /* Todo: add real Mute control code */
  95        .set = generic_set_cmd,
  96        .get = generic_get_cmd,
  97};
  98
  99static struct usb_audio_control volume_control = {
 100        .list = LIST_HEAD_INIT(volume_control.list),
 101        .name = "Volume Control",
 102        .type = UAC_FU_VOLUME,
 103        /* Todo: add real Volume control code */
 104        .set = generic_set_cmd,
 105        .get = generic_get_cmd,
 106};
 107
 108static struct usb_audio_control_selector feature_unit = {
 109        .list = LIST_HEAD_INIT(feature_unit.list),
 110        .id = FEATURE_UNIT_ID,
 111        .name = "Mute & Volume Control",
 112        .type = UAC_FEATURE_UNIT,
 113        .desc = (struct usb_descriptor_header *)&feature_unit_desc,
 114};
 115
 116#define OUTPUT_TERMINAL_ID      3
 117static struct uac1_output_terminal_descriptor output_terminal_desc = {
 118        .bLength                = UAC_DT_OUTPUT_TERMINAL_SIZE,
 119        .bDescriptorType        = USB_DT_CS_INTERFACE,
 120        .bDescriptorSubtype     = UAC_OUTPUT_TERMINAL,
 121        .bTerminalID            = OUTPUT_TERMINAL_ID,
 122        .wTerminalType          = UAC_OUTPUT_TERMINAL_SPEAKER,
 123        .bAssocTerminal         = FEATURE_UNIT_ID,
 124        .bSourceID              = FEATURE_UNIT_ID,
 125};
 126
 127/* B.4.1  Standard AS Interface Descriptor */
 128static struct usb_interface_descriptor as_interface_alt_0_desc = {
 129        .bLength =              USB_DT_INTERFACE_SIZE,
 130        .bDescriptorType =      USB_DT_INTERFACE,
 131        .bAlternateSetting =    0,
 132        .bNumEndpoints =        0,
 133        .bInterfaceClass =      USB_CLASS_AUDIO,
 134        .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 135};
 136
 137static struct usb_interface_descriptor as_interface_alt_1_desc = {
 138        .bLength =              USB_DT_INTERFACE_SIZE,
 139        .bDescriptorType =      USB_DT_INTERFACE,
 140        .bAlternateSetting =    1,
 141        .bNumEndpoints =        1,
 142        .bInterfaceClass =      USB_CLASS_AUDIO,
 143        .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 144};
 145
 146/* B.4.2  Class-Specific AS Interface Descriptor */
 147static struct uac1_as_header_descriptor as_header_desc = {
 148        .bLength =              UAC_DT_AS_HEADER_SIZE,
 149        .bDescriptorType =      USB_DT_CS_INTERFACE,
 150        .bDescriptorSubtype =   UAC_AS_GENERAL,
 151        .bTerminalLink =        INPUT_TERMINAL_ID,
 152        .bDelay =               1,
 153        .wFormatTag =           UAC_FORMAT_TYPE_I_PCM,
 154};
 155
 156DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
 157
 158static struct uac_format_type_i_discrete_descriptor_1 as_type_i_desc = {
 159        .bLength =              UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
 160        .bDescriptorType =      USB_DT_CS_INTERFACE,
 161        .bDescriptorSubtype =   UAC_FORMAT_TYPE,
 162        .bFormatType =          UAC_FORMAT_TYPE_I,
 163        .bSubframeSize =        2,
 164        .bBitResolution =       16,
 165        .bSamFreqType =         1,
 166};
 167
 168/* Standard ISO OUT Endpoint Descriptor */
 169static struct usb_endpoint_descriptor as_out_ep_desc  = {
 170        .bLength =              USB_DT_ENDPOINT_AUDIO_SIZE,
 171        .bDescriptorType =      USB_DT_ENDPOINT,
 172        .bEndpointAddress =     USB_DIR_OUT,
 173        .bmAttributes =         USB_ENDPOINT_SYNC_ADAPTIVE
 174                                | USB_ENDPOINT_XFER_ISOC,
 175        .wMaxPacketSize =       cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
 176        .bInterval =            4,
 177};
 178
 179/* Class-specific AS ISO OUT Endpoint Descriptor */
 180static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
 181        .bLength =              UAC_ISO_ENDPOINT_DESC_SIZE,
 182        .bDescriptorType =      USB_DT_CS_ENDPOINT,
 183        .bDescriptorSubtype =   UAC_EP_GENERAL,
 184        .bmAttributes =         1,
 185        .bLockDelayUnits =      1,
 186        .wLockDelay =           cpu_to_le16(1),
 187};
 188
 189static struct usb_descriptor_header *f_audio_desc[] = {
 190        (struct usb_descriptor_header *)&ac_interface_desc,
 191        (struct usb_descriptor_header *)&ac_header_desc,
 192
 193        (struct usb_descriptor_header *)&input_terminal_desc,
 194        (struct usb_descriptor_header *)&output_terminal_desc,
 195        (struct usb_descriptor_header *)&feature_unit_desc,
 196
 197        (struct usb_descriptor_header *)&as_interface_alt_0_desc,
 198        (struct usb_descriptor_header *)&as_interface_alt_1_desc,
 199        (struct usb_descriptor_header *)&as_header_desc,
 200
 201        (struct usb_descriptor_header *)&as_type_i_desc,
 202
 203        (struct usb_descriptor_header *)&as_out_ep_desc,
 204        (struct usb_descriptor_header *)&as_iso_out_desc,
 205        NULL,
 206};
 207
 208enum {
 209        STR_AC_IF,
 210        STR_INPUT_TERMINAL,
 211        STR_INPUT_TERMINAL_CH_NAMES,
 212        STR_FEAT_DESC_0,
 213        STR_OUTPUT_TERMINAL,
 214        STR_AS_IF_ALT0,
 215        STR_AS_IF_ALT1,
 216};
 217
 218static struct usb_string strings_uac1[] = {
 219        [STR_AC_IF].s = "AC Interface",
 220        [STR_INPUT_TERMINAL].s = "Input terminal",
 221        [STR_INPUT_TERMINAL_CH_NAMES].s = "Channels",
 222        [STR_FEAT_DESC_0].s = "Volume control & mute",
 223        [STR_OUTPUT_TERMINAL].s = "Output terminal",
 224        [STR_AS_IF_ALT0].s = "AS Interface",
 225        [STR_AS_IF_ALT1].s = "AS Interface",
 226        { },
 227};
 228
 229static struct usb_gadget_strings str_uac1 = {
 230        .language = 0x0409,     /* en-us */
 231        .strings = strings_uac1,
 232};
 233
 234static struct usb_gadget_strings *uac1_strings[] = {
 235        &str_uac1,
 236        NULL,
 237};
 238
 239/*
 240 * This function is an ALSA sound card following USB Audio Class Spec 1.0.
 241 */
 242
 243/*-------------------------------------------------------------------------*/
 244struct f_audio_buf {
 245        u8 *buf;
 246        int actual;
 247        struct list_head list;
 248};
 249
 250static struct f_audio_buf *f_audio_buffer_alloc(int buf_size)
 251{
 252        struct f_audio_buf *copy_buf;
 253
 254        copy_buf = kzalloc(sizeof *copy_buf, GFP_ATOMIC);
 255        if (!copy_buf)
 256                return ERR_PTR(-ENOMEM);
 257
 258        copy_buf->buf = kzalloc(buf_size, GFP_ATOMIC);
 259        if (!copy_buf->buf) {
 260                kfree(copy_buf);
 261                return ERR_PTR(-ENOMEM);
 262        }
 263
 264        return copy_buf;
 265}
 266
 267static void f_audio_buffer_free(struct f_audio_buf *audio_buf)
 268{
 269        kfree(audio_buf->buf);
 270        kfree(audio_buf);
 271}
 272/*-------------------------------------------------------------------------*/
 273
 274struct f_audio {
 275        struct gaudio                   card;
 276
 277        u8 ac_intf, ac_alt;
 278        u8 as_intf, as_alt;
 279
 280        /* endpoints handle full and/or high speeds */
 281        struct usb_ep                   *out_ep;
 282
 283        spinlock_t                      lock;
 284        struct f_audio_buf *copy_buf;
 285        struct work_struct playback_work;
 286        struct list_head play_queue;
 287
 288        /* Control Set command */
 289        struct list_head cs;
 290        u8 set_cmd;
 291        struct usb_audio_control *set_con;
 292};
 293
 294static inline struct f_audio *func_to_audio(struct usb_function *f)
 295{
 296        return container_of(f, struct f_audio, card.func);
 297}
 298
 299/*-------------------------------------------------------------------------*/
 300
 301static void f_audio_playback_work(struct work_struct *data)
 302{
 303        struct f_audio *audio = container_of(data, struct f_audio,
 304                                        playback_work);
 305        struct f_audio_buf *play_buf;
 306
 307        spin_lock_irq(&audio->lock);
 308        if (list_empty(&audio->play_queue)) {
 309                spin_unlock_irq(&audio->lock);
 310                return;
 311        }
 312        play_buf = list_first_entry(&audio->play_queue,
 313                        struct f_audio_buf, list);
 314        list_del(&play_buf->list);
 315        spin_unlock_irq(&audio->lock);
 316
 317        u_audio_playback(&audio->card, play_buf->buf, play_buf->actual);
 318        f_audio_buffer_free(play_buf);
 319}
 320
 321static int f_audio_out_ep_complete(struct usb_ep *ep, struct usb_request *req)
 322{
 323        struct f_audio *audio = req->context;
 324        struct usb_composite_dev *cdev = audio->card.func.config->cdev;
 325        struct f_audio_buf *copy_buf = audio->copy_buf;
 326        struct f_uac1_legacy_opts *opts;
 327        int audio_buf_size;
 328        int err;
 329
 330        opts = container_of(audio->card.func.fi, struct f_uac1_legacy_opts,
 331                            func_inst);
 332        audio_buf_size = opts->audio_buf_size;
 333
 334        if (!copy_buf)
 335                return -EINVAL;
 336
 337        /* Copy buffer is full, add it to the play_queue */
 338        if (audio_buf_size - copy_buf->actual < req->actual) {
 339                spin_lock_irq(&audio->lock);
 340                list_add_tail(&copy_buf->list, &audio->play_queue);
 341                spin_unlock_irq(&audio->lock);
 342                schedule_work(&audio->playback_work);
 343                copy_buf = f_audio_buffer_alloc(audio_buf_size);
 344                if (IS_ERR(copy_buf))
 345                        return -ENOMEM;
 346        }
 347
 348        memcpy(copy_buf->buf + copy_buf->actual, req->buf, req->actual);
 349        copy_buf->actual += req->actual;
 350        audio->copy_buf = copy_buf;
 351
 352        err = usb_ep_queue(ep, req, GFP_ATOMIC);
 353        if (err)
 354                ERROR(cdev, "%s queue req: %d\n", ep->name, err);
 355
 356        return 0;
 357
 358}
 359
 360static void f_audio_complete(struct usb_ep *ep, struct usb_request *req)
 361{
 362        struct f_audio *audio = req->context;
 363        int status = req->status;
 364        u32 data = 0;
 365        struct usb_ep *out_ep = audio->out_ep;
 366
 367        switch (status) {
 368
 369        case 0:                         /* normal completion? */
 370                if (ep == out_ep)
 371                        f_audio_out_ep_complete(ep, req);
 372                else if (audio->set_con) {
 373                        memcpy(&data, req->buf, req->length);
 374                        audio->set_con->set(audio->set_con, audio->set_cmd,
 375                                        le16_to_cpu(data));
 376                        audio->set_con = NULL;
 377                }
 378                break;
 379        default:
 380                break;
 381        }
 382}
 383
 384static int audio_set_intf_req(struct usb_function *f,
 385                const struct usb_ctrlrequest *ctrl)
 386{
 387        struct f_audio          *audio = func_to_audio(f);
 388        struct usb_composite_dev *cdev = f->config->cdev;
 389        struct usb_request      *req = cdev->req;
 390        u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 391        u16                     len = le16_to_cpu(ctrl->wLength);
 392        u16                     w_value = le16_to_cpu(ctrl->wValue);
 393        u8                      con_sel = (w_value >> 8) & 0xFF;
 394        u8                      cmd = (ctrl->bRequest & 0x0F);
 395        struct usb_audio_control_selector *cs;
 396        struct usb_audio_control *con;
 397
 398        DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 399                        ctrl->bRequest, w_value, len, id);
 400
 401        list_for_each_entry(cs, &audio->cs, list) {
 402                if (cs->id == id) {
 403                        list_for_each_entry(con, &cs->control, list) {
 404                                if (con->type == con_sel) {
 405                                        audio->set_con = con;
 406                                        break;
 407                                }
 408                        }
 409                        break;
 410                }
 411        }
 412
 413        audio->set_cmd = cmd;
 414        req->context = audio;
 415        req->complete = f_audio_complete;
 416
 417        return len;
 418}
 419
 420static int audio_get_intf_req(struct usb_function *f,
 421                const struct usb_ctrlrequest *ctrl)
 422{
 423        struct f_audio          *audio = func_to_audio(f);
 424        struct usb_composite_dev *cdev = f->config->cdev;
 425        struct usb_request      *req = cdev->req;
 426        int                     value = -EOPNOTSUPP;
 427        u8                      id = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 428        u16                     len = le16_to_cpu(ctrl->wLength);
 429        u16                     w_value = le16_to_cpu(ctrl->wValue);
 430        u8                      con_sel = (w_value >> 8) & 0xFF;
 431        u8                      cmd = (ctrl->bRequest & 0x0F);
 432        struct usb_audio_control_selector *cs;
 433        struct usb_audio_control *con;
 434
 435        DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, entity %d\n",
 436                        ctrl->bRequest, w_value, len, id);
 437
 438        list_for_each_entry(cs, &audio->cs, list) {
 439                if (cs->id == id) {
 440                        list_for_each_entry(con, &cs->control, list) {
 441                                if (con->type == con_sel && con->get) {
 442                                        value = con->get(con, cmd);
 443                                        break;
 444                                }
 445                        }
 446                        break;
 447                }
 448        }
 449
 450        req->context = audio;
 451        req->complete = f_audio_complete;
 452        len = min_t(size_t, sizeof(value), len);
 453        memcpy(req->buf, &value, len);
 454
 455        return len;
 456}
 457
 458static int audio_set_endpoint_req(struct usb_function *f,
 459                const struct usb_ctrlrequest *ctrl)
 460{
 461        struct usb_composite_dev *cdev = f->config->cdev;
 462        int                     value = -EOPNOTSUPP;
 463        u16                     ep = le16_to_cpu(ctrl->wIndex);
 464        u16                     len = le16_to_cpu(ctrl->wLength);
 465        u16                     w_value = le16_to_cpu(ctrl->wValue);
 466
 467        DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 468                        ctrl->bRequest, w_value, len, ep);
 469
 470        switch (ctrl->bRequest) {
 471        case UAC_SET_CUR:
 472                value = len;
 473                break;
 474
 475        case UAC_SET_MIN:
 476                break;
 477
 478        case UAC_SET_MAX:
 479                break;
 480
 481        case UAC_SET_RES:
 482                break;
 483
 484        case UAC_SET_MEM:
 485                break;
 486
 487        default:
 488                break;
 489        }
 490
 491        return value;
 492}
 493
 494static int audio_get_endpoint_req(struct usb_function *f,
 495                const struct usb_ctrlrequest *ctrl)
 496{
 497        struct usb_composite_dev *cdev = f->config->cdev;
 498        int value = -EOPNOTSUPP;
 499        u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 500        u16 len = le16_to_cpu(ctrl->wLength);
 501        u16 w_value = le16_to_cpu(ctrl->wValue);
 502
 503        DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 504                        ctrl->bRequest, w_value, len, ep);
 505
 506        switch (ctrl->bRequest) {
 507        case UAC_GET_CUR:
 508        case UAC_GET_MIN:
 509        case UAC_GET_MAX:
 510        case UAC_GET_RES:
 511                value = len;
 512                break;
 513        case UAC_GET_MEM:
 514                break;
 515        default:
 516                break;
 517        }
 518
 519        return value;
 520}
 521
 522static int
 523f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 524{
 525        struct usb_composite_dev *cdev = f->config->cdev;
 526        struct usb_request      *req = cdev->req;
 527        int                     value = -EOPNOTSUPP;
 528        u16                     w_index = le16_to_cpu(ctrl->wIndex);
 529        u16                     w_value = le16_to_cpu(ctrl->wValue);
 530        u16                     w_length = le16_to_cpu(ctrl->wLength);
 531
 532        /* composite driver infrastructure handles everything; interface
 533         * activation uses set_alt().
 534         */
 535        switch (ctrl->bRequestType) {
 536        case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 537                value = audio_set_intf_req(f, ctrl);
 538                break;
 539
 540        case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE:
 541                value = audio_get_intf_req(f, ctrl);
 542                break;
 543
 544        case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 545                value = audio_set_endpoint_req(f, ctrl);
 546                break;
 547
 548        case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 549                value = audio_get_endpoint_req(f, ctrl);
 550                break;
 551
 552        default:
 553                ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 554                        ctrl->bRequestType, ctrl->bRequest,
 555                        w_value, w_index, w_length);
 556        }
 557
 558        /* respond with data transfer or status phase? */
 559        if (value >= 0) {
 560                DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
 561                        ctrl->bRequestType, ctrl->bRequest,
 562                        w_value, w_index, w_length);
 563                req->zero = 0;
 564                req->length = value;
 565                value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 566                if (value < 0)
 567                        ERROR(cdev, "audio response on err %d\n", value);
 568        }
 569
 570        /* device either stalls (value < 0) or reports success */
 571        return value;
 572}
 573
 574static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 575{
 576        struct f_audio          *audio = func_to_audio(f);
 577        struct usb_composite_dev *cdev = f->config->cdev;
 578        struct usb_ep *out_ep = audio->out_ep;
 579        struct usb_request *req;
 580        struct f_uac1_legacy_opts *opts;
 581        int req_buf_size, req_count, audio_buf_size;
 582        int i = 0, err = 0;
 583
 584        DBG(cdev, "intf %d, alt %d\n", intf, alt);
 585
 586        opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
 587        req_buf_size = opts->req_buf_size;
 588        req_count = opts->req_count;
 589        audio_buf_size = opts->audio_buf_size;
 590
 591        /* No i/f has more than 2 alt settings */
 592        if (alt > 1) {
 593                ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
 594                return -EINVAL;
 595        }
 596
 597        if (intf == audio->ac_intf) {
 598                /* Control I/f has only 1 AltSetting - 0 */
 599                if (alt) {
 600                        ERROR(cdev, "%s:%d Error!\n", __func__, __LINE__);
 601                        return -EINVAL;
 602                }
 603                return 0;
 604        } else if (intf == audio->as_intf) {
 605                if (alt == 1) {
 606                        err = config_ep_by_speed(cdev->gadget, f, out_ep);
 607                        if (err)
 608                                return err;
 609
 610                        usb_ep_enable(out_ep);
 611                        audio->copy_buf = f_audio_buffer_alloc(audio_buf_size);
 612                        if (IS_ERR(audio->copy_buf))
 613                                return -ENOMEM;
 614
 615                        /*
 616                         * allocate a bunch of read buffers
 617                         * and queue them all at once.
 618                         */
 619                        for (i = 0; i < req_count && err == 0; i++) {
 620                                req = usb_ep_alloc_request(out_ep, GFP_ATOMIC);
 621                                if (req) {
 622                                        req->buf = kzalloc(req_buf_size,
 623                                                        GFP_ATOMIC);
 624                                        if (req->buf) {
 625                                                req->length = req_buf_size;
 626                                                req->context = audio;
 627                                                req->complete =
 628                                                        f_audio_complete;
 629                                                err = usb_ep_queue(out_ep,
 630                                                        req, GFP_ATOMIC);
 631                                                if (err)
 632                                                        ERROR(cdev,
 633                                                        "%s queue req: %d\n",
 634                                                        out_ep->name, err);
 635                                        } else
 636                                                err = -ENOMEM;
 637                                } else
 638                                        err = -ENOMEM;
 639                        }
 640
 641                } else {
 642                        struct f_audio_buf *copy_buf = audio->copy_buf;
 643                        if (copy_buf) {
 644                                list_add_tail(&copy_buf->list,
 645                                                &audio->play_queue);
 646                                schedule_work(&audio->playback_work);
 647                        }
 648                }
 649                audio->as_alt = alt;
 650        }
 651
 652        return err;
 653}
 654
 655static int f_audio_get_alt(struct usb_function *f, unsigned intf)
 656{
 657        struct f_audio          *audio = func_to_audio(f);
 658        struct usb_composite_dev *cdev = f->config->cdev;
 659
 660        if (intf == audio->ac_intf)
 661                return audio->ac_alt;
 662        else if (intf == audio->as_intf)
 663                return audio->as_alt;
 664        else
 665                ERROR(cdev, "%s:%d Invalid Interface %d!\n",
 666                      __func__, __LINE__, intf);
 667
 668        return -EINVAL;
 669}
 670
 671static void f_audio_disable(struct usb_function *f)
 672{
 673        return;
 674}
 675
 676/*-------------------------------------------------------------------------*/
 677
 678static void f_audio_build_desc(struct f_audio *audio)
 679{
 680        struct gaudio *card = &audio->card;
 681        u8 *sam_freq;
 682        int rate;
 683
 684        /* Set channel numbers */
 685        input_terminal_desc.bNrChannels = u_audio_get_playback_channels(card);
 686        as_type_i_desc.bNrChannels = u_audio_get_playback_channels(card);
 687
 688        /* Set sample rates */
 689        rate = u_audio_get_playback_rate(card);
 690        sam_freq = as_type_i_desc.tSamFreq[0];
 691        memcpy(sam_freq, &rate, 3);
 692
 693        /* Todo: Set Sample bits and other parameters */
 694
 695        return;
 696}
 697
 698/* audio function driver setup/binding */
 699static int
 700f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 701{
 702        struct usb_composite_dev *cdev = c->cdev;
 703        struct f_audio          *audio = func_to_audio(f);
 704        struct usb_string       *us;
 705        int                     status;
 706        struct usb_ep           *ep = NULL;
 707        struct f_uac1_legacy_opts       *audio_opts;
 708
 709        audio_opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
 710        audio->card.gadget = c->cdev->gadget;
 711        /* set up ASLA audio devices */
 712        if (!audio_opts->bound) {
 713                status = gaudio_setup(&audio->card);
 714                if (status < 0)
 715                        return status;
 716                audio_opts->bound = true;
 717        }
 718        us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
 719        if (IS_ERR(us))
 720                return PTR_ERR(us);
 721        ac_interface_desc.iInterface = us[STR_AC_IF].id;
 722        input_terminal_desc.iTerminal = us[STR_INPUT_TERMINAL].id;
 723        input_terminal_desc.iChannelNames = us[STR_INPUT_TERMINAL_CH_NAMES].id;
 724        feature_unit_desc.iFeature = us[STR_FEAT_DESC_0].id;
 725        output_terminal_desc.iTerminal = us[STR_OUTPUT_TERMINAL].id;
 726        as_interface_alt_0_desc.iInterface = us[STR_AS_IF_ALT0].id;
 727        as_interface_alt_1_desc.iInterface = us[STR_AS_IF_ALT1].id;
 728
 729
 730        f_audio_build_desc(audio);
 731
 732        /* allocate instance-specific interface IDs, and patch descriptors */
 733        status = usb_interface_id(c, f);
 734        if (status < 0)
 735                goto fail;
 736        ac_interface_desc.bInterfaceNumber = status;
 737        audio->ac_intf = status;
 738        audio->ac_alt = 0;
 739
 740        status = usb_interface_id(c, f);
 741        if (status < 0)
 742                goto fail;
 743        as_interface_alt_0_desc.bInterfaceNumber = status;
 744        as_interface_alt_1_desc.bInterfaceNumber = status;
 745        audio->as_intf = status;
 746        audio->as_alt = 0;
 747
 748        status = -ENODEV;
 749
 750        /* allocate instance-specific endpoints */
 751        ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
 752        if (!ep)
 753                goto fail;
 754        audio->out_ep = ep;
 755        audio->out_ep->desc = &as_out_ep_desc;
 756
 757        /* copy descriptors, and track endpoint copies */
 758        status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
 759                                        NULL);
 760        if (status)
 761                goto fail;
 762        return 0;
 763
 764fail:
 765        gaudio_cleanup(&audio->card);
 766        return status;
 767}
 768
 769/*-------------------------------------------------------------------------*/
 770
 771static int generic_set_cmd(struct usb_audio_control *con, u8 cmd, int value)
 772{
 773        con->data[cmd] = value;
 774
 775        return 0;
 776}
 777
 778static int generic_get_cmd(struct usb_audio_control *con, u8 cmd)
 779{
 780        return con->data[cmd];
 781}
 782
 783/* Todo: add more control selecotor dynamically */
 784static int control_selector_init(struct f_audio *audio)
 785{
 786        INIT_LIST_HEAD(&audio->cs);
 787        list_add(&feature_unit.list, &audio->cs);
 788
 789        INIT_LIST_HEAD(&feature_unit.control);
 790        list_add(&mute_control.list, &feature_unit.control);
 791        list_add(&volume_control.list, &feature_unit.control);
 792
 793        volume_control.data[UAC__CUR] = 0xffc0;
 794        volume_control.data[UAC__MIN] = 0xe3a0;
 795        volume_control.data[UAC__MAX] = 0xfff0;
 796        volume_control.data[UAC__RES] = 0x0030;
 797
 798        return 0;
 799}
 800
 801static inline
 802struct f_uac1_legacy_opts *to_f_uac1_opts(struct config_item *item)
 803{
 804        return container_of(to_config_group(item), struct f_uac1_legacy_opts,
 805                            func_inst.group);
 806}
 807
 808static void f_uac1_attr_release(struct config_item *item)
 809{
 810        struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);
 811
 812        usb_put_function_instance(&opts->func_inst);
 813}
 814
 815static struct configfs_item_operations f_uac1_item_ops = {
 816        .release        = f_uac1_attr_release,
 817};
 818
 819#define UAC1_INT_ATTRIBUTE(name)                                        \
 820static ssize_t f_uac1_opts_##name##_show(struct config_item *item,      \
 821                                         char *page)                    \
 822{                                                                       \
 823        struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 824        int result;                                                     \
 825                                                                        \
 826        mutex_lock(&opts->lock);                                        \
 827        result = sprintf(page, "%u\n", opts->name);                     \
 828        mutex_unlock(&opts->lock);                                      \
 829                                                                        \
 830        return result;                                                  \
 831}                                                                       \
 832                                                                        \
 833static ssize_t f_uac1_opts_##name##_store(struct config_item *item,             \
 834                                          const char *page, size_t len) \
 835{                                                                       \
 836        struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 837        int ret;                                                        \
 838        u32 num;                                                        \
 839                                                                        \
 840        mutex_lock(&opts->lock);                                        \
 841        if (opts->refcnt) {                                             \
 842                ret = -EBUSY;                                           \
 843                goto end;                                               \
 844        }                                                               \
 845                                                                        \
 846        ret = kstrtou32(page, 0, &num);                                 \
 847        if (ret)                                                        \
 848                goto end;                                               \
 849                                                                        \
 850        opts->name = num;                                               \
 851        ret = len;                                                      \
 852                                                                        \
 853end:                                                                    \
 854        mutex_unlock(&opts->lock);                                      \
 855        return ret;                                                     \
 856}                                                                       \
 857                                                                        \
 858CONFIGFS_ATTR(f_uac1_opts_, name)
 859
 860UAC1_INT_ATTRIBUTE(req_buf_size);
 861UAC1_INT_ATTRIBUTE(req_count);
 862UAC1_INT_ATTRIBUTE(audio_buf_size);
 863
 864#define UAC1_STR_ATTRIBUTE(name)                                        \
 865static ssize_t f_uac1_opts_##name##_show(struct config_item *item,      \
 866                                         char *page)                    \
 867{                                                                       \
 868        struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 869        int result;                                                     \
 870                                                                        \
 871        mutex_lock(&opts->lock);                                        \
 872        result = sprintf(page, "%s\n", opts->name);                     \
 873        mutex_unlock(&opts->lock);                                      \
 874                                                                        \
 875        return result;                                                  \
 876}                                                                       \
 877                                                                        \
 878static ssize_t f_uac1_opts_##name##_store(struct config_item *item,     \
 879                                          const char *page, size_t len) \
 880{                                                                       \
 881        struct f_uac1_legacy_opts *opts = to_f_uac1_opts(item);         \
 882        int ret = -EBUSY;                                               \
 883        char *tmp;                                                      \
 884                                                                        \
 885        mutex_lock(&opts->lock);                                        \
 886        if (opts->refcnt)                                               \
 887                goto end;                                               \
 888                                                                        \
 889        tmp = kstrndup(page, len, GFP_KERNEL);                          \
 890        if (tmp) {                                                      \
 891                ret = -ENOMEM;                                          \
 892                goto end;                                               \
 893        }                                                               \
 894        if (opts->name##_alloc)                                         \
 895                kfree(opts->name);                                      \
 896        opts->name##_alloc = true;                                      \
 897        opts->name = tmp;                                               \
 898        ret = len;                                                      \
 899                                                                        \
 900end:                                                                    \
 901        mutex_unlock(&opts->lock);                                      \
 902        return ret;                                                     \
 903}                                                                       \
 904                                                                        \
 905CONFIGFS_ATTR(f_uac1_opts_, name)
 906
 907UAC1_STR_ATTRIBUTE(fn_play);
 908UAC1_STR_ATTRIBUTE(fn_cap);
 909UAC1_STR_ATTRIBUTE(fn_cntl);
 910
 911static struct configfs_attribute *f_uac1_attrs[] = {
 912        &f_uac1_opts_attr_req_buf_size,
 913        &f_uac1_opts_attr_req_count,
 914        &f_uac1_opts_attr_audio_buf_size,
 915        &f_uac1_opts_attr_fn_play,
 916        &f_uac1_opts_attr_fn_cap,
 917        &f_uac1_opts_attr_fn_cntl,
 918        NULL,
 919};
 920
 921static const struct config_item_type f_uac1_func_type = {
 922        .ct_item_ops    = &f_uac1_item_ops,
 923        .ct_attrs       = f_uac1_attrs,
 924        .ct_owner       = THIS_MODULE,
 925};
 926
 927static void f_audio_free_inst(struct usb_function_instance *f)
 928{
 929        struct f_uac1_legacy_opts *opts;
 930
 931        opts = container_of(f, struct f_uac1_legacy_opts, func_inst);
 932        if (opts->fn_play_alloc)
 933                kfree(opts->fn_play);
 934        if (opts->fn_cap_alloc)
 935                kfree(opts->fn_cap);
 936        if (opts->fn_cntl_alloc)
 937                kfree(opts->fn_cntl);
 938        kfree(opts);
 939}
 940
 941static struct usb_function_instance *f_audio_alloc_inst(void)
 942{
 943        struct f_uac1_legacy_opts *opts;
 944
 945        opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 946        if (!opts)
 947                return ERR_PTR(-ENOMEM);
 948
 949        mutex_init(&opts->lock);
 950        opts->func_inst.free_func_inst = f_audio_free_inst;
 951
 952        config_group_init_type_name(&opts->func_inst.group, "",
 953                                    &f_uac1_func_type);
 954
 955        opts->req_buf_size = UAC1_OUT_EP_MAX_PACKET_SIZE;
 956        opts->req_count = UAC1_REQ_COUNT;
 957        opts->audio_buf_size = UAC1_AUDIO_BUF_SIZE;
 958        opts->fn_play = FILE_PCM_PLAYBACK;
 959        opts->fn_cap = FILE_PCM_CAPTURE;
 960        opts->fn_cntl = FILE_CONTROL;
 961        return &opts->func_inst;
 962}
 963
 964static void f_audio_free(struct usb_function *f)
 965{
 966        struct f_audio *audio = func_to_audio(f);
 967        struct f_uac1_legacy_opts *opts;
 968
 969        gaudio_cleanup(&audio->card);
 970        opts = container_of(f->fi, struct f_uac1_legacy_opts, func_inst);
 971        kfree(audio);
 972        mutex_lock(&opts->lock);
 973        --opts->refcnt;
 974        mutex_unlock(&opts->lock);
 975}
 976
 977static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 978{
 979        usb_free_all_descriptors(f);
 980}
 981
 982static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
 983{
 984        struct f_audio *audio;
 985        struct f_uac1_legacy_opts *opts;
 986
 987        /* allocate and initialize one new instance */
 988        audio = kzalloc(sizeof(*audio), GFP_KERNEL);
 989        if (!audio)
 990                return ERR_PTR(-ENOMEM);
 991
 992        audio->card.func.name = "g_audio";
 993
 994        opts = container_of(fi, struct f_uac1_legacy_opts, func_inst);
 995        mutex_lock(&opts->lock);
 996        ++opts->refcnt;
 997        mutex_unlock(&opts->lock);
 998        INIT_LIST_HEAD(&audio->play_queue);
 999        spin_lock_init(&audio->lock);
1000
1001        audio->card.func.bind = f_audio_bind;
1002        audio->card.func.unbind = f_audio_unbind;
1003        audio->card.func.set_alt = f_audio_set_alt;
1004        audio->card.func.get_alt = f_audio_get_alt;
1005        audio->card.func.setup = f_audio_setup;
1006        audio->card.func.disable = f_audio_disable;
1007        audio->card.func.free_func = f_audio_free;
1008
1009        control_selector_init(audio);
1010
1011        INIT_WORK(&audio->playback_work, f_audio_playback_work);
1012
1013        return &audio->card.func;
1014}
1015
1016DECLARE_USB_FUNCTION_INIT(uac1_legacy, f_audio_alloc_inst, f_audio_alloc);
1017MODULE_LICENSE("GPL");
1018MODULE_AUTHOR("Bryan Wu");
1019