drivers/usb/gadget/function/f_uac1.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * f_uac1.c -- USB Audio Class 1.0 Function (using u_audio API)
   4  *
   5  * Copyright (C) 2016 Ruslan Bilovol <ruslan.bilovol@gmail.com>
   6  *
   7  * This driver doesn't expect any real Audio codec to be present
   8  * on the device - the audio streams are simply sinked to and
   9  * sourced from a virtual ALSA sound card created.
  10  *
  11  * This file is based on f_uac1.c which is
  12  *   Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
  13  *   Copyright (C) 2008 Analog Devices, Inc
  14  */
  15
  16 #include <linux/usb/audio.h>
  17 #include <linux/module.h>
  18
  19 #include "u_audio.h"
  20 #include "u_uac1.h"
  21
  22 struct f_uac1 {
  23         struct g_audio g_audio;
  24         u8 ac_intf, as_in_intf, as_out_intf;
  25         u8 ac_alt, as_in_alt, as_out_alt;       /* needed for get_alt() */
  26 };
  27
  28 static inline struct f_uac1 *func_to_uac1(struct usb_function *f)
  29 {
  30         return container_of(f, struct f_uac1, g_audio.func);
  31 }
  32
  33 /*
  34  * DESCRIPTORS ... most are static, but strings and full
  35  * configuration descriptors are built on demand.
  36  */
  37
  38 /*
  39  * We have three interfaces - one AudioControl and two AudioStreaming
  40  *
  41  * The driver implements a simple UAC_1 topology.
  42  * USB-OUT -> IT_1 -> OT_2 -> ALSA_Capture
  43  * ALSA_Playback -> IT_3 -> OT_4 -> USB-IN
  44  */
  45 #define F_AUDIO_AC_INTERFACE            0
  46 #define F_AUDIO_AS_OUT_INTERFACE        1
  47 #define F_AUDIO_AS_IN_INTERFACE         2
  48 /* Number of streaming interfaces */
  49 #define F_AUDIO_NUM_INTERFACES          2
  50
  51 /* B.3.1  Standard AC Interface Descriptor */
  52 static struct usb_interface_descriptor ac_interface_desc = {
  53         .bLength =              USB_DT_INTERFACE_SIZE,
  54         .bDescriptorType =      USB_DT_INTERFACE,
  55         .bNumEndpoints =        0,
  56         .bInterfaceClass =      USB_CLASS_AUDIO,
  57         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOCONTROL,
  58 };
  59
  60 /*
  61  * The number of AudioStreaming and MIDIStreaming interfaces
  62  * in the Audio Interface Collection
  63  */
  64 DECLARE_UAC_AC_HEADER_DESCRIPTOR(2);
  65
  66 #define UAC_DT_AC_HEADER_LENGTH UAC_DT_AC_HEADER_SIZE(F_AUDIO_NUM_INTERFACES)
  67 /* 2 input terminals and 2 output terminals */
  68 #define UAC_DT_TOTAL_LENGTH (UAC_DT_AC_HEADER_LENGTH \
  69         + 2*UAC_DT_INPUT_TERMINAL_SIZE + 2*UAC_DT_OUTPUT_TERMINAL_SIZE)
  70 /* B.3.2  Class-Specific AC Interface Descriptor */
  71 static struct uac1_ac_header_descriptor_2 ac_header_desc = {
  72         .bLength =              UAC_DT_AC_HEADER_LENGTH,
  73         .bDescriptorType =      USB_DT_CS_INTERFACE,
  74         .bDescriptorSubtype =   UAC_HEADER,
  75         .bcdADC =               cpu_to_le16(0x0100),
  76         .wTotalLength =         cpu_to_le16(UAC_DT_TOTAL_LENGTH),
  77         .bInCollection =        F_AUDIO_NUM_INTERFACES,
  78         .baInterfaceNr = {
  79         /* Interface number of the AudioStream interfaces */
  80                 [0] =           1,
  81                 [1] =           2,
  82         }
  83 };
  84
  85 #define USB_OUT_IT_ID   1
  86 static struct uac_input_terminal_descriptor usb_out_it_desc = {
  87         .bLength =              UAC_DT_INPUT_TERMINAL_SIZE,
  88         .bDescriptorType =      USB_DT_CS_INTERFACE,
  89         .bDescriptorSubtype =   UAC_INPUT_TERMINAL,
  90         .bTerminalID =          USB_OUT_IT_ID,
  91         .wTerminalType =        cpu_to_le16(UAC_TERMINAL_STREAMING),
  92         .bAssocTerminal =       0,
  93         .wChannelConfig =       cpu_to_le16(0x3),
  94 };
  95
  96 #define IO_OUT_OT_ID    2
  97 static struct uac1_output_terminal_descriptor io_out_ot_desc = {
  98         .bLength                = UAC_DT_OUTPUT_TERMINAL_SIZE,
  99         .bDescriptorType        = USB_DT_CS_INTERFACE,
 100         .bDescriptorSubtype     = UAC_OUTPUT_TERMINAL,
 101         .bTerminalID            = IO_OUT_OT_ID,
 102         .wTerminalType          = cpu_to_le16(UAC_OUTPUT_TERMINAL_SPEAKER),
 103         .bAssocTerminal         = 0,
 104         .bSourceID              = USB_OUT_IT_ID,
 105 };
 106
 107 #define IO_IN_IT_ID     3
 108 static struct uac_input_terminal_descriptor io_in_it_desc = {
 109         .bLength                = UAC_DT_INPUT_TERMINAL_SIZE,
 110         .bDescriptorType        = USB_DT_CS_INTERFACE,
 111         .bDescriptorSubtype     = UAC_INPUT_TERMINAL,
 112         .bTerminalID            = IO_IN_IT_ID,
 113         .wTerminalType          = cpu_to_le16(UAC_INPUT_TERMINAL_MICROPHONE),
 114         .bAssocTerminal         = 0,
 115         .wChannelConfig         = cpu_to_le16(0x3),
 116 };
 117
 118 #define USB_IN_OT_ID    4
 119 static struct uac1_output_terminal_descriptor usb_in_ot_desc = {
 120         .bLength =              UAC_DT_OUTPUT_TERMINAL_SIZE,
 121         .bDescriptorType =      USB_DT_CS_INTERFACE,
 122         .bDescriptorSubtype =   UAC_OUTPUT_TERMINAL,
 123         .bTerminalID =          USB_IN_OT_ID,
 124         .wTerminalType =        cpu_to_le16(UAC_TERMINAL_STREAMING),
 125         .bAssocTerminal =       0,
 126         .bSourceID =            IO_IN_IT_ID,
 127 };
 128
 129 /* B.4.1  Standard AS Interface Descriptor */
 130 static struct usb_interface_descriptor as_out_interface_alt_0_desc = {
 131         .bLength =              USB_DT_INTERFACE_SIZE,
 132         .bDescriptorType =      USB_DT_INTERFACE,
 133         .bAlternateSetting =    0,
 134         .bNumEndpoints =        0,
 135         .bInterfaceClass =      USB_CLASS_AUDIO,
 136         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 137 };
 138
 139 static struct usb_interface_descriptor as_out_interface_alt_1_desc = {
 140         .bLength =              USB_DT_INTERFACE_SIZE,
 141         .bDescriptorType =      USB_DT_INTERFACE,
 142         .bAlternateSetting =    1,
 143         .bNumEndpoints =        1,
 144         .bInterfaceClass =      USB_CLASS_AUDIO,
 145         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 146 };
 147
 148 static struct usb_interface_descriptor as_in_interface_alt_0_desc = {
 149         .bLength =              USB_DT_INTERFACE_SIZE,
 150         .bDescriptorType =      USB_DT_INTERFACE,
 151         .bAlternateSetting =    0,
 152         .bNumEndpoints =        0,
 153         .bInterfaceClass =      USB_CLASS_AUDIO,
 154         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 155 };
 156
 157 static struct usb_interface_descriptor as_in_interface_alt_1_desc = {
 158         .bLength =              USB_DT_INTERFACE_SIZE,
 159         .bDescriptorType =      USB_DT_INTERFACE,
 160         .bAlternateSetting =    1,
 161         .bNumEndpoints =        1,
 162         .bInterfaceClass =      USB_CLASS_AUDIO,
 163         .bInterfaceSubClass =   USB_SUBCLASS_AUDIOSTREAMING,
 164 };
 165
 166 /* B.4.2  Class-Specific AS Interface Descriptor */
 167 static struct uac1_as_header_descriptor as_out_header_desc = {
 168         .bLength =              UAC_DT_AS_HEADER_SIZE,
 169         .bDescriptorType =      USB_DT_CS_INTERFACE,
 170         .bDescriptorSubtype =   UAC_AS_GENERAL,
 171         .bTerminalLink =        USB_OUT_IT_ID,
 172         .bDelay =               1,
 173         .wFormatTag =           cpu_to_le16(UAC_FORMAT_TYPE_I_PCM),
 174 };
 175
 176 static struct uac1_as_header_descriptor as_in_header_desc = {
 177         .bLength =              UAC_DT_AS_HEADER_SIZE,
 178         .bDescriptorType =      USB_DT_CS_INTERFACE,
 179         .bDescriptorSubtype =   UAC_AS_GENERAL,
 180         .bTerminalLink =        USB_IN_OT_ID,
 181         .bDelay =               1,
 182         .wFormatTag =           cpu_to_le16(UAC_FORMAT_TYPE_I_PCM),
 183 };
 184
 185 DECLARE_UAC_FORMAT_TYPE_I_DISCRETE_DESC(1);
 186
 187 static struct uac_format_type_i_discrete_descriptor_1 as_out_type_i_desc = {
 188         .bLength =              UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
 189         .bDescriptorType =      USB_DT_CS_INTERFACE,
 190         .bDescriptorSubtype =   UAC_FORMAT_TYPE,
 191         .bFormatType =          UAC_FORMAT_TYPE_I,
 192         .bSubframeSize =        2,
 193         .bBitResolution =       16,
 194         .bSamFreqType =         1,
 195 };
 196
 197 /* Standard ISO OUT Endpoint Descriptor */
 198 static struct usb_endpoint_descriptor as_out_ep_desc  = {
 199         .bLength =              USB_DT_ENDPOINT_AUDIO_SIZE,
 200         .bDescriptorType =      USB_DT_ENDPOINT,
 201         .bEndpointAddress =     USB_DIR_OUT,
 202         .bmAttributes =         USB_ENDPOINT_SYNC_ADAPTIVE
 203                                 | USB_ENDPOINT_XFER_ISOC,
 204         .wMaxPacketSize =       cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
 205         .bInterval =            4,
 206 };
 207
 208 /* Class-specific AS ISO OUT Endpoint Descriptor */
 209 static struct uac_iso_endpoint_descriptor as_iso_out_desc = {
 210         .bLength =              UAC_ISO_ENDPOINT_DESC_SIZE,
 211         .bDescriptorType =      USB_DT_CS_ENDPOINT,
 212         .bDescriptorSubtype =   UAC_EP_GENERAL,
 213         .bmAttributes =         1,
 214         .bLockDelayUnits =      1,
 215         .wLockDelay =           cpu_to_le16(1),
 216 };
 217
 218 static struct uac_format_type_i_discrete_descriptor_1 as_in_type_i_desc = {
 219         .bLength =              UAC_FORMAT_TYPE_I_DISCRETE_DESC_SIZE(1),
 220         .bDescriptorType =      USB_DT_CS_INTERFACE,
 221         .bDescriptorSubtype =   UAC_FORMAT_TYPE,
 222         .bFormatType =          UAC_FORMAT_TYPE_I,
 223         .bSubframeSize =        2,
 224         .bBitResolution =       16,
 225         .bSamFreqType =         1,
 226 };
 227
 228 /* Standard ISO OUT Endpoint Descriptor */
 229 static struct usb_endpoint_descriptor as_in_ep_desc  = {
 230         .bLength =              USB_DT_ENDPOINT_AUDIO_SIZE,
 231         .bDescriptorType =      USB_DT_ENDPOINT,
 232         .bEndpointAddress =     USB_DIR_IN,
 233         .bmAttributes =         USB_ENDPOINT_SYNC_ASYNC
 234                                 | USB_ENDPOINT_XFER_ISOC,
 235         .wMaxPacketSize =       cpu_to_le16(UAC1_OUT_EP_MAX_PACKET_SIZE),
 236         .bInterval =            4,
 237 };
 238
 239 /* Class-specific AS ISO OUT Endpoint Descriptor */
 240 static struct uac_iso_endpoint_descriptor as_iso_in_desc = {
 241         .bLength =              UAC_ISO_ENDPOINT_DESC_SIZE,
 242         .bDescriptorType =      USB_DT_CS_ENDPOINT,
 243         .bDescriptorSubtype =   UAC_EP_GENERAL,
 244         .bmAttributes =         1,
 245         .bLockDelayUnits =      0,
 246         .wLockDelay =           0,
 247 };
 248
 249 static struct usb_descriptor_header *f_audio_desc[] = {
 250         (struct usb_descriptor_header *)&ac_interface_desc,
 251         (struct usb_descriptor_header *)&ac_header_desc,
 252
 253         (struct usb_descriptor_header *)&usb_out_it_desc,
 254         (struct usb_descriptor_header *)&io_out_ot_desc,
 255         (struct usb_descriptor_header *)&io_in_it_desc,
 256         (struct usb_descriptor_header *)&usb_in_ot_desc,
 257
 258         (struct usb_descriptor_header *)&as_out_interface_alt_0_desc,
 259         (struct usb_descriptor_header *)&as_out_interface_alt_1_desc,
 260         (struct usb_descriptor_header *)&as_out_header_desc,
 261
 262         (struct usb_descriptor_header *)&as_out_type_i_desc,
 263
 264         (struct usb_descriptor_header *)&as_out_ep_desc,
 265         (struct usb_descriptor_header *)&as_iso_out_desc,
 266
 267         (struct usb_descriptor_header *)&as_in_interface_alt_0_desc,
 268         (struct usb_descriptor_header *)&as_in_interface_alt_1_desc,
 269         (struct usb_descriptor_header *)&as_in_header_desc,
 270
 271         (struct usb_descriptor_header *)&as_in_type_i_desc,
 272
 273         (struct usb_descriptor_header *)&as_in_ep_desc,
 274         (struct usb_descriptor_header *)&as_iso_in_desc,
 275         NULL,
 276 };
 277
 278 enum {
 279         STR_AC_IF,
 280         STR_USB_OUT_IT,
 281         STR_USB_OUT_IT_CH_NAMES,
 282         STR_IO_OUT_OT,
 283         STR_IO_IN_IT,
 284         STR_IO_IN_IT_CH_NAMES,
 285         STR_USB_IN_OT,
 286         STR_AS_OUT_IF_ALT0,
 287         STR_AS_OUT_IF_ALT1,
 288         STR_AS_IN_IF_ALT0,
 289         STR_AS_IN_IF_ALT1,
 290 };
 291
 292 static struct usb_string strings_uac1[] = {
 293         [STR_AC_IF].s = "AC Interface",
 294         [STR_USB_OUT_IT].s = "Playback Input terminal",
 295         [STR_USB_OUT_IT_CH_NAMES].s = "Playback Channels",
 296         [STR_IO_OUT_OT].s = "Playback Output terminal",
 297         [STR_IO_IN_IT].s = "Capture Input terminal",
 298         [STR_IO_IN_IT_CH_NAMES].s = "Capture Channels",
 299         [STR_USB_IN_OT].s = "Capture Output terminal",
 300         [STR_AS_OUT_IF_ALT0].s = "Playback Inactive",
 301         [STR_AS_OUT_IF_ALT1].s = "Playback Active",
 302         [STR_AS_IN_IF_ALT0].s = "Capture Inactive",
 303         [STR_AS_IN_IF_ALT1].s = "Capture Active",
 304         { },
 305 };
 306
 307 static struct usb_gadget_strings str_uac1 = {
 308         .language = 0x0409,     /* en-us */
 309         .strings = strings_uac1,
 310 };
 311
 312 static struct usb_gadget_strings *uac1_strings[] = {
 313         &str_uac1,
 314         NULL,
 315 };
 316
 317 /*
 318  * This function is an ALSA sound card following USB Audio Class Spec 1.0.
 319  */
 320
 321 static int audio_set_endpoint_req(struct usb_function *f,
 322                 const struct usb_ctrlrequest *ctrl)
 323 {
 324         struct usb_composite_dev *cdev = f->config->cdev;
 325         int                     value = -EOPNOTSUPP;
 326         u16                     ep = le16_to_cpu(ctrl->wIndex);
 327         u16                     len = le16_to_cpu(ctrl->wLength);
 328         u16                     w_value = le16_to_cpu(ctrl->wValue);
 329
 330         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 331                         ctrl->bRequest, w_value, len, ep);
 332
 333         switch (ctrl->bRequest) {
 334         case UAC_SET_CUR:
 335                 value = len;
 336                 break;
 337
 338         case UAC_SET_MIN:
 339                 break;
 340
 341         case UAC_SET_MAX:
 342                 break;
 343
 344         case UAC_SET_RES:
 345                 break;
 346
 347         case UAC_SET_MEM:
 348                 break;
 349
 350         default:
 351                 break;
 352         }
 353
 354         return value;
 355 }
 356
 357 static int audio_get_endpoint_req(struct usb_function *f,
 358                 const struct usb_ctrlrequest *ctrl)
 359 {
 360         struct usb_composite_dev *cdev = f->config->cdev;
 361         int value = -EOPNOTSUPP;
 362         u8 ep = ((le16_to_cpu(ctrl->wIndex) >> 8) & 0xFF);
 363         u16 len = le16_to_cpu(ctrl->wLength);
 364         u16 w_value = le16_to_cpu(ctrl->wValue);
 365
 366         DBG(cdev, "bRequest 0x%x, w_value 0x%04x, len %d, endpoint %d\n",
 367                         ctrl->bRequest, w_value, len, ep);
 368
 369         switch (ctrl->bRequest) {
 370         case UAC_GET_CUR:
 371         case UAC_GET_MIN:
 372         case UAC_GET_MAX:
 373         case UAC_GET_RES:
 374                 value = len;
 375                 break;
 376         case UAC_GET_MEM:
 377                 break;
 378         default:
 379                 break;
 380         }
 381
 382         return value;
 383 }
 384
 385 static int
 386 f_audio_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 387 {
 388         struct usb_composite_dev *cdev = f->config->cdev;
 389         struct usb_request      *req = cdev->req;
 390         int                     value = -EOPNOTSUPP;
 391         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 392         u16                     w_value = le16_to_cpu(ctrl->wValue);
 393         u16                     w_length = le16_to_cpu(ctrl->wLength);
 394
 395         /* composite driver infrastructure handles everything; interface
 396          * activation uses set_alt().
 397          */
 398         switch (ctrl->bRequestType) {
 399         case USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 400                 value = audio_set_endpoint_req(f, ctrl);
 401                 break;
 402
 403         case USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_ENDPOINT:
 404                 value = audio_get_endpoint_req(f, ctrl);
 405                 break;
 406
 407         default:
 408                 ERROR(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 409                         ctrl->bRequestType, ctrl->bRequest,
 410                         w_value, w_index, w_length);
 411         }
 412
 413         /* respond with data transfer or status phase? */
 414         if (value >= 0) {
 415                 DBG(cdev, "audio req%02x.%02x v%04x i%04x l%d\n",
 416                         ctrl->bRequestType, ctrl->bRequest,
 417                         w_value, w_index, w_length);
 418                 req->zero = 0;
 419                 req->length = value;
 420                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 421                 if (value < 0)
 422                         ERROR(cdev, "audio response on err %d\n", value);
 423         }
 424
 425         /* device either stalls (value < 0) or reports success */
 426         return value;
 427 }
 428
 429 static int f_audio_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 430 {
 431         struct usb_composite_dev *cdev = f->config->cdev;
 432         struct usb_gadget *gadget = cdev->gadget;
 433         struct device *dev = &gadget->dev;
 434         struct f_uac1 *uac1 = func_to_uac1(f);
 435         int ret = 0;
 436
 437         /* No i/f has more than 2 alt settings */
 438         if (alt > 1) {
 439                 dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 440                 return -EINVAL;
 441         }
 442
 443         if (intf == uac1->ac_intf) {
 444                 /* Control I/f has only 1 AltSetting - 0 */
 445                 if (alt) {
 446                         dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 447                         return -EINVAL;
 448                 }
 449                 return 0;
 450         }
 451
 452         if (intf == uac1->as_out_intf) {
 453                 uac1->as_out_alt = alt;
 454
 455                 if (alt)
 456                         ret = u_audio_start_capture(&uac1->g_audio);
 457                 else
 458                         u_audio_stop_capture(&uac1->g_audio);
 459         } else if (intf == uac1->as_in_intf) {
 460                 uac1->as_in_alt = alt;
 461
 462                         if (alt)
 463                                 ret = u_audio_start_playback(&uac1->g_audio);
 464                         else
 465                                 u_audio_stop_playback(&uac1->g_audio);
 466         } else {
 467                 dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
 468                 return -EINVAL;
 469         }
 470
 471         return ret;
 472 }
 473
 474 static int f_audio_get_alt(struct usb_function *f, unsigned intf)
 475 {
 476         struct usb_composite_dev *cdev = f->config->cdev;
 477         struct usb_gadget *gadget = cdev->gadget;
 478         struct device *dev = &gadget->dev;
 479         struct f_uac1 *uac1 = func_to_uac1(f);
 480
 481         if (intf == uac1->ac_intf)
 482                 return uac1->ac_alt;
 483         else if (intf == uac1->as_out_intf)
 484                 return uac1->as_out_alt;
 485         else if (intf == uac1->as_in_intf)
 486                 return uac1->as_in_alt;
 487         else
 488                 dev_err(dev, "%s:%d Invalid Interface %d!\n",
 489                         __func__, __LINE__, intf);
 490
 491         return -EINVAL;
 492 }
 493
 494
 495 static void f_audio_disable(struct usb_function *f)
 496 {
 497         struct f_uac1 *uac1 = func_to_uac1(f);
 498
 499         uac1->as_out_alt = 0;
 500         uac1->as_in_alt = 0;
 501
 502         u_audio_stop_capture(&uac1->g_audio);
 503 }
 504
 505 /*-------------------------------------------------------------------------*/
 506
 507 /* audio function driver setup/binding */
 508 static int f_audio_bind(struct usb_configuration *c, struct usb_function *f)
 509 {
 510         struct usb_composite_dev        *cdev = c->cdev;
 511         struct usb_gadget               *gadget = cdev->gadget;
 512         struct f_uac1                   *uac1 = func_to_uac1(f);
 513         struct g_audio                  *audio = func_to_g_audio(f);
 514         struct f_uac1_opts              *audio_opts;
 515         struct usb_ep                   *ep = NULL;
 516         struct usb_string               *us;
 517         u8                              *sam_freq;
 518         int                             rate;
 519         int                             status;
 520
 521         audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst);
 522
 523         us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1));
 524         if (IS_ERR(us))
 525                 return PTR_ERR(us);
 526         ac_interface_desc.iInterface = us[STR_AC_IF].id;
 527         usb_out_it_desc.iTerminal = us[STR_USB_OUT_IT].id;
 528         usb_out_it_desc.iChannelNames = us[STR_USB_OUT_IT_CH_NAMES].id;
 529         io_out_ot_desc.iTerminal = us[STR_IO_OUT_OT].id;
 530         as_out_interface_alt_0_desc.iInterface = us[STR_AS_OUT_IF_ALT0].id;
 531         as_out_interface_alt_1_desc.iInterface = us[STR_AS_OUT_IF_ALT1].id;
 532         io_in_it_desc.iTerminal = us[STR_IO_IN_IT].id;
 533         io_in_it_desc.iChannelNames = us[STR_IO_IN_IT_CH_NAMES].id;
 534         usb_in_ot_desc.iTerminal = us[STR_USB_IN_OT].id;
 535         as_in_interface_alt_0_desc.iInterface = us[STR_AS_IN_IF_ALT0].id;
 536         as_in_interface_alt_1_desc.iInterface = us[STR_AS_IN_IF_ALT1].id;
 537
 538         /* Set channel numbers */
 539         usb_out_it_desc.bNrChannels = num_channels(audio_opts->c_chmask);
 540         usb_out_it_desc.wChannelConfig = cpu_to_le16(audio_opts->c_chmask);
 541         as_out_type_i_desc.bNrChannels = num_channels(audio_opts->c_chmask);
 542         as_out_type_i_desc.bSubframeSize = audio_opts->c_ssize;
 543         as_out_type_i_desc.bBitResolution = audio_opts->c_ssize * 8;
 544         io_in_it_desc.bNrChannels = num_channels(audio_opts->p_chmask);
 545         io_in_it_desc.wChannelConfig = cpu_to_le16(audio_opts->p_chmask);
 546         as_in_type_i_desc.bNrChannels = num_channels(audio_opts->p_chmask);
 547         as_in_type_i_desc.bSubframeSize = audio_opts->p_ssize;
 548         as_in_type_i_desc.bBitResolution = audio_opts->p_ssize * 8;
 549
 550         /* Set sample rates */
 551         rate = audio_opts->c_srate;
 552         sam_freq = as_out_type_i_desc.tSamFreq[0];
 553         memcpy(sam_freq, &rate, 3);
 554         rate = audio_opts->p_srate;
 555         sam_freq = as_in_type_i_desc.tSamFreq[0];
 556         memcpy(sam_freq, &rate, 3);
 557
 558         /* allocate instance-specific interface IDs, and patch descriptors */
 559         status = usb_interface_id(c, f);
 560         if (status < 0)
 561                 goto fail;
 562         ac_interface_desc.bInterfaceNumber = status;
 563         uac1->ac_intf = status;
 564         uac1->ac_alt = 0;
 565
 566         status = usb_interface_id(c, f);
 567         if (status < 0)
 568                 goto fail;
 569         as_out_interface_alt_0_desc.bInterfaceNumber = status;
 570         as_out_interface_alt_1_desc.bInterfaceNumber = status;
 571         uac1->as_out_intf = status;
 572         uac1->as_out_alt = 0;
 573
 574         status = usb_interface_id(c, f);
 575         if (status < 0)
 576                 goto fail;
 577         as_in_interface_alt_0_desc.bInterfaceNumber = status;
 578         as_in_interface_alt_1_desc.bInterfaceNumber = status;
 579         uac1->as_in_intf = status;
 580         uac1->as_in_alt = 0;
 581
 582         audio->gadget = gadget;
 583
 584         status = -ENODEV;
 585
 586         /* allocate instance-specific endpoints */
 587         ep = usb_ep_autoconfig(cdev->gadget, &as_out_ep_desc);
 588         if (!ep)
 589                 goto fail;
 590         audio->out_ep = ep;
 591         audio->out_ep->desc = &as_out_ep_desc;
 592
 593         ep = usb_ep_autoconfig(cdev->gadget, &as_in_ep_desc);
 594         if (!ep)
 595                 goto fail;
 596         audio->in_ep = ep;
 597         audio->in_ep->desc = &as_in_ep_desc;
 598
 599         /* copy descriptors, and track endpoint copies */
 600         status = usb_assign_descriptors(f, f_audio_desc, f_audio_desc, NULL,
 601                                         NULL);
 602         if (status)
 603                 goto fail;
 604
 605         audio->out_ep_maxpsize = le16_to_cpu(as_out_ep_desc.wMaxPacketSize);
 606         audio->in_ep_maxpsize = le16_to_cpu(as_in_ep_desc.wMaxPacketSize);
 607         audio->params.c_chmask = audio_opts->c_chmask;
 608         audio->params.c_srate = audio_opts->c_srate;
 609         audio->params.c_ssize = audio_opts->c_ssize;
 610         audio->params.p_chmask = audio_opts->p_chmask;
 611         audio->params.p_srate = audio_opts->p_srate;
 612         audio->params.p_ssize = audio_opts->p_ssize;
 613         audio->params.req_number = audio_opts->req_number;
 614
 615         status = g_audio_setup(audio, "UAC1_PCM", "UAC1_Gadget");
 616         if (status)
 617                 goto err_card_register;
 618
 619         return 0;
 620
 621 err_card_register:
 622         usb_free_all_descriptors(f);
 623 fail:
 624         return status;
 625 }
 626
 627 /*-------------------------------------------------------------------------*/
 628
 629 static inline struct f_uac1_opts *to_f_uac1_opts(struct config_item *item)
 630 {
 631         return container_of(to_config_group(item), struct f_uac1_opts,
 632                             func_inst.group);
 633 }
 634
 635 static void f_uac1_attr_release(struct config_item *item)
 636 {
 637         struct f_uac1_opts *opts = to_f_uac1_opts(item);
 638
 639         usb_put_function_instance(&opts->func_inst);
 640 }
 641
 642 static struct configfs_item_operations f_uac1_item_ops = {
 643         .release        = f_uac1_attr_release,
 644 };
 645
 646 #define UAC1_ATTRIBUTE(name)                                            \
 647 static ssize_t f_uac1_opts_##name##_show(                               \
 648                                           struct config_item *item,     \
 649                                           char *page)                   \
 650 {                                                                       \
 651         struct f_uac1_opts *opts = to_f_uac1_opts(item);                \
 652         int result;                                                     \
 653                                                                         \
 654         mutex_lock(&opts->lock);                                        \
 655         result = sprintf(page, "%u\n", opts->name);                     \
 656         mutex_unlock(&opts->lock);                                      \
 657                                                                         \
 658         return result;                                                  \
 659 }                                                                       \
 660                                                                         \
 661 static ssize_t f_uac1_opts_##name##_store(                              \
 662                                           struct config_item *item,     \
 663                                           const char *page, size_t len) \
 664 {                                                                       \
 665         struct f_uac1_opts *opts = to_f_uac1_opts(item);                \
 666         int ret;                                                        \
 667         u32 num;                                                        \
 668                                                                         \
 669         mutex_lock(&opts->lock);                                        \
 670         if (opts->refcnt) {                                             \
 671                 ret = -EBUSY;                                           \
 672                 goto end;                                               \
 673         }                                                               \
 674                                                                         \
 675         ret = kstrtou32(page, 0, &num);                                 \
 676         if (ret)                                                        \
 677                 goto end;                                               \
 678                                                                         \
 679         opts->name = num;                                               \
 680         ret = len;                                                      \
 681                                                                         \
 682 end:                                                                    \
 683         mutex_unlock(&opts->lock);                                      \
 684         return ret;                                                     \
 685 }                                                                       \
 686                                                                         \
 687 CONFIGFS_ATTR(f_uac1_opts_, name)
 688
 689 UAC1_ATTRIBUTE(c_chmask);
 690 UAC1_ATTRIBUTE(c_srate);
 691 UAC1_ATTRIBUTE(c_ssize);
 692 UAC1_ATTRIBUTE(p_chmask);
 693 UAC1_ATTRIBUTE(p_srate);
 694 UAC1_ATTRIBUTE(p_ssize);
 695 UAC1_ATTRIBUTE(req_number);
 696
 697 static struct configfs_attribute *f_uac1_attrs[] = {
 698         &f_uac1_opts_attr_c_chmask,
 699         &f_uac1_opts_attr_c_srate,
 700         &f_uac1_opts_attr_c_ssize,
 701         &f_uac1_opts_attr_p_chmask,
 702         &f_uac1_opts_attr_p_srate,
 703         &f_uac1_opts_attr_p_ssize,
 704         &f_uac1_opts_attr_req_number,
 705         NULL,
 706 };
 707
 708 static const struct config_item_type f_uac1_func_type = {
 709         .ct_item_ops    = &f_uac1_item_ops,
 710         .ct_attrs       = f_uac1_attrs,
 711         .ct_owner       = THIS_MODULE,
 712 };
 713
 714 static void f_audio_free_inst(struct usb_function_instance *f)
 715 {
 716         struct f_uac1_opts *opts;
 717
 718         opts = container_of(f, struct f_uac1_opts, func_inst);
 719         kfree(opts);
 720 }
 721
 722 static struct usb_function_instance *f_audio_alloc_inst(void)
 723 {
 724         struct f_uac1_opts *opts;
 725
 726         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 727         if (!opts)
 728                 return ERR_PTR(-ENOMEM);
 729
 730         mutex_init(&opts->lock);
 731         opts->func_inst.free_func_inst = f_audio_free_inst;
 732
 733         config_group_init_type_name(&opts->func_inst.group, "",
 734                                     &f_uac1_func_type);
 735
 736         opts->c_chmask = UAC1_DEF_CCHMASK;
 737         opts->c_srate = UAC1_DEF_CSRATE;
 738         opts->c_ssize = UAC1_DEF_CSSIZE;
 739         opts->p_chmask = UAC1_DEF_PCHMASK;
 740         opts->p_srate = UAC1_DEF_PSRATE;
 741         opts->p_ssize = UAC1_DEF_PSSIZE;
 742         opts->req_number = UAC1_DEF_REQ_NUM;
 743         return &opts->func_inst;
 744 }
 745
 746 static void f_audio_free(struct usb_function *f)
 747 {
 748         struct g_audio *audio;
 749         struct f_uac1_opts *opts;
 750
 751         audio = func_to_g_audio(f);
 752         opts = container_of(f->fi, struct f_uac1_opts, func_inst);
 753         kfree(audio);
 754         mutex_lock(&opts->lock);
 755         --opts->refcnt;
 756         mutex_unlock(&opts->lock);
 757 }
 758
 759 static void f_audio_unbind(struct usb_configuration *c, struct usb_function *f)
 760 {
 761         struct g_audio *audio = func_to_g_audio(f);
 762
 763         g_audio_cleanup(audio);
 764         usb_free_all_descriptors(f);
 765
 766         audio->gadget = NULL;
 767 }
 768
 769 static struct usb_function *f_audio_alloc(struct usb_function_instance *fi)
 770 {
 771         struct f_uac1 *uac1;
 772         struct f_uac1_opts *opts;
 773
 774         /* allocate and initialize one new instance */
 775         uac1 = kzalloc(sizeof(*uac1), GFP_KERNEL);
 776         if (!uac1)
 777                 return ERR_PTR(-ENOMEM);
 778
 779         opts = container_of(fi, struct f_uac1_opts, func_inst);
 780         mutex_lock(&opts->lock);
 781         ++opts->refcnt;
 782         mutex_unlock(&opts->lock);
 783
 784         uac1->g_audio.func.name = "uac1_func";
 785         uac1->g_audio.func.bind = f_audio_bind;
 786         uac1->g_audio.func.unbind = f_audio_unbind;
 787         uac1->g_audio.func.set_alt = f_audio_set_alt;
 788         uac1->g_audio.func.get_alt = f_audio_get_alt;
 789         uac1->g_audio.func.setup = f_audio_setup;
 790         uac1->g_audio.func.disable = f_audio_disable;
 791         uac1->g_audio.func.free_func = f_audio_free;
 792
 793         return &uac1->g_audio.func;
 794 }
 795
 796 DECLARE_USB_FUNCTION_INIT(uac1, f_audio_alloc_inst, f_audio_alloc);
 797 MODULE_LICENSE("GPL");
 798 MODULE_AUTHOR("Ruslan Bilovol");