drivers/usb/gadget/function/f_ncm.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * f_ncm.c -- USB CDC Network (NCM) link function driver
   4  *
   5  * Copyright (C) 2010 Nokia Corporation
   6  * Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com>
   7  *
   8  * The driver borrows from f_ecm.c which is:
   9  *
  10  * Copyright (C) 2003-2005,2008 David Brownell
  11  * Copyright (C) 2008 Nokia Corporation
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/module.h>
  17 #include <linux/device.h>
  18 #include <linux/etherdevice.h>
  19 #include <linux/crc32.h>
  20
  21 #include <linux/usb/cdc.h>
  22
  23 #include "u_ether.h"
  24 #include "u_ether_configfs.h"
  25 #include "u_ncm.h"
  26 #include "configfs.h"
  27
  28 /*
  29  * This function is a "CDC Network Control Model" (CDC NCM) Ethernet link.
  30  * NCM is intended to be used with high-speed network attachments.
  31  *
  32  * Note that NCM requires the use of "alternate settings" for its data
  33  * interface.  This means that the set_alt() method has real work to do,
  34  * and also means that a get_alt() method is required.
  35  */
  36
  37 /* to trigger crc/non-crc ndp signature */
  38
  39 #define NCM_NDP_HDR_CRC         0x01000000
  40
  41 enum ncm_notify_state {
  42         NCM_NOTIFY_NONE,                /* don't notify */
  43         NCM_NOTIFY_CONNECT,             /* issue CONNECT next */
  44         NCM_NOTIFY_SPEED,               /* issue SPEED_CHANGE next */
  45 };
  46
  47 struct f_ncm {
  48         struct gether                   port;
  49         u8                              ctrl_id, data_id;
  50
  51         char                            ethaddr[14];
  52
  53         struct usb_ep                   *notify;
  54         struct usb_request              *notify_req;
  55         u8                              notify_state;
  56         atomic_t                        notify_count;
  57         bool                            is_open;
  58
  59         const struct ndp_parser_opts    *parser_opts;
  60         bool                            is_crc;
  61         u32                             ndp_sign;
  62
  63         /*
  64          * for notification, it is accessed from both
  65          * callback and ethernet open/close
  66          */
  67         spinlock_t                      lock;
  68
  69         struct net_device               *netdev;
  70
  71         /* For multi-frame NDP TX */
  72         struct sk_buff                  *skb_tx_data;
  73         struct sk_buff                  *skb_tx_ndp;
  74         u16                             ndp_dgram_count;
  75         struct hrtimer                  task_timer;
  76 };
  77
  78 static inline struct f_ncm *func_to_ncm(struct usb_function *f)
  79 {
  80         return container_of(f, struct f_ncm, port.func);
  81 }
  82
  83 /* peak (theoretical) bulk transfer rate in bits-per-second */
  84 static inline unsigned ncm_bitrate(struct usb_gadget *g)
  85 {
  86         if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
  87                 return 4250000000U;
  88         else if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
  89                 return 3750000000U;
  90         else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
  91                 return 13 * 512 * 8 * 1000 * 8;
  92         else
  93                 return 19 *  64 * 1 * 1000 * 8;
  94 }
  95
  96 /*-------------------------------------------------------------------------*/
  97
  98 /*
  99  * We cannot group frames so use just the minimal size which ok to put
 100  * one max-size ethernet frame.
 101  * If the host can group frames, allow it to do that, 16K is selected,
 102  * because it's used by default by the current linux host driver
 103  */
 104 #define NTB_DEFAULT_IN_SIZE     16384
 105 #define NTB_OUT_SIZE            16384
 106
 107 /* Allocation for storing the NDP, 32 should suffice for a
 108  * 16k packet. This allows a maximum of 32 * 507 Byte packets to
 109  * be transmitted in a single 16kB skb, though when sending full size
 110  * packets this limit will be plenty.
 111  * Smaller packets are not likely to be trying to maximize the
 112  * throughput and will be mstly sending smaller infrequent frames.
 113  */
 114 #define TX_MAX_NUM_DPE          32
 115
 116 /* Delay for the transmit to wait before sending an unfilled NTB frame. */
 117 #define TX_TIMEOUT_NSECS        300000
 118
 119 #define FORMATS_SUPPORTED       (USB_CDC_NCM_NTB16_SUPPORTED |  \
 120                                  USB_CDC_NCM_NTB32_SUPPORTED)
 121
 122 static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
 123         .wLength = cpu_to_le16(sizeof(ntb_parameters)),
 124         .bmNtbFormatsSupported = cpu_to_le16(FORMATS_SUPPORTED),
 125         .dwNtbInMaxSize = cpu_to_le32(NTB_DEFAULT_IN_SIZE),
 126         .wNdpInDivisor = cpu_to_le16(4),
 127         .wNdpInPayloadRemainder = cpu_to_le16(0),
 128         .wNdpInAlignment = cpu_to_le16(4),
 129
 130         .dwNtbOutMaxSize = cpu_to_le32(NTB_OUT_SIZE),
 131         .wNdpOutDivisor = cpu_to_le16(4),
 132         .wNdpOutPayloadRemainder = cpu_to_le16(0),
 133         .wNdpOutAlignment = cpu_to_le16(4),
 134 };
 135
 136 /*
 137  * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
 138  * packet, to simplify cancellation; and a big transfer interval, to
 139  * waste less bandwidth.
 140  */
 141
 142 #define NCM_STATUS_INTERVAL_MS          32
 143 #define NCM_STATUS_BYTECOUNT            16      /* 8 byte header + data */
 144
 145 static struct usb_interface_assoc_descriptor ncm_iad_desc = {
 146         .bLength =              sizeof ncm_iad_desc,
 147         .bDescriptorType =      USB_DT_INTERFACE_ASSOCIATION,
 148
 149         /* .bFirstInterface =   DYNAMIC, */
 150         .bInterfaceCount =      2,      /* control + data */
 151         .bFunctionClass =       USB_CLASS_COMM,
 152         .bFunctionSubClass =    USB_CDC_SUBCLASS_NCM,
 153         .bFunctionProtocol =    USB_CDC_PROTO_NONE,
 154         /* .iFunction =         DYNAMIC */
 155 };
 156
 157 /* interface descriptor: */
 158
 159 static struct usb_interface_descriptor ncm_control_intf = {
 160         .bLength =              sizeof ncm_control_intf,
 161         .bDescriptorType =      USB_DT_INTERFACE,
 162
 163         /* .bInterfaceNumber = DYNAMIC */
 164         .bNumEndpoints =        1,
 165         .bInterfaceClass =      USB_CLASS_COMM,
 166         .bInterfaceSubClass =   USB_CDC_SUBCLASS_NCM,
 167         .bInterfaceProtocol =   USB_CDC_PROTO_NONE,
 168         /* .iInterface = DYNAMIC */
 169 };
 170
 171 static struct usb_cdc_header_desc ncm_header_desc = {
 172         .bLength =              sizeof ncm_header_desc,
 173         .bDescriptorType =      USB_DT_CS_INTERFACE,
 174         .bDescriptorSubType =   USB_CDC_HEADER_TYPE,
 175
 176         .bcdCDC =               cpu_to_le16(0x0110),
 177 };
 178
 179 static struct usb_cdc_union_desc ncm_union_desc = {
 180         .bLength =              sizeof(ncm_union_desc),
 181         .bDescriptorType =      USB_DT_CS_INTERFACE,
 182         .bDescriptorSubType =   USB_CDC_UNION_TYPE,
 183         /* .bMasterInterface0 = DYNAMIC */
 184         /* .bSlaveInterface0 =  DYNAMIC */
 185 };
 186
 187 static struct usb_cdc_ether_desc ecm_desc = {
 188         .bLength =              sizeof ecm_desc,
 189         .bDescriptorType =      USB_DT_CS_INTERFACE,
 190         .bDescriptorSubType =   USB_CDC_ETHERNET_TYPE,
 191
 192         /* this descriptor actually adds value, surprise! */
 193         /* .iMACAddress = DYNAMIC */
 194         .bmEthernetStatistics = cpu_to_le32(0), /* no statistics */
 195         .wMaxSegmentSize =      cpu_to_le16(ETH_FRAME_LEN),
 196         .wNumberMCFilters =     cpu_to_le16(0),
 197         .bNumberPowerFilters =  0,
 198 };
 199
 200 #define NCAPS   (USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
 201
 202 static struct usb_cdc_ncm_desc ncm_desc = {
 203         .bLength =              sizeof ncm_desc,
 204         .bDescriptorType =      USB_DT_CS_INTERFACE,
 205         .bDescriptorSubType =   USB_CDC_NCM_TYPE,
 206
 207         .bcdNcmVersion =        cpu_to_le16(0x0100),
 208         /* can process SetEthernetPacketFilter */
 209         .bmNetworkCapabilities = NCAPS,
 210 };
 211
 212 /* the default data interface has no endpoints ... */
 213
 214 static struct usb_interface_descriptor ncm_data_nop_intf = {
 215         .bLength =              sizeof ncm_data_nop_intf,
 216         .bDescriptorType =      USB_DT_INTERFACE,
 217
 218         .bInterfaceNumber =     1,
 219         .bAlternateSetting =    0,
 220         .bNumEndpoints =        0,
 221         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 222         .bInterfaceSubClass =   0,
 223         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 224         /* .iInterface = DYNAMIC */
 225 };
 226
 227 /* ... but the "real" data interface has two bulk endpoints */
 228
 229 static struct usb_interface_descriptor ncm_data_intf = {
 230         .bLength =              sizeof ncm_data_intf,
 231         .bDescriptorType =      USB_DT_INTERFACE,
 232
 233         .bInterfaceNumber =     1,
 234         .bAlternateSetting =    1,
 235         .bNumEndpoints =        2,
 236         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 237         .bInterfaceSubClass =   0,
 238         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 239         /* .iInterface = DYNAMIC */
 240 };
 241
 242 /* full speed support: */
 243
 244 static struct usb_endpoint_descriptor fs_ncm_notify_desc = {
 245         .bLength =              USB_DT_ENDPOINT_SIZE,
 246         .bDescriptorType =      USB_DT_ENDPOINT,
 247
 248         .bEndpointAddress =     USB_DIR_IN,
 249         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 250         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 251         .bInterval =            NCM_STATUS_INTERVAL_MS,
 252 };
 253
 254 static struct usb_endpoint_descriptor fs_ncm_in_desc = {
 255         .bLength =              USB_DT_ENDPOINT_SIZE,
 256         .bDescriptorType =      USB_DT_ENDPOINT,
 257
 258         .bEndpointAddress =     USB_DIR_IN,
 259         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 260 };
 261
 262 static struct usb_endpoint_descriptor fs_ncm_out_desc = {
 263         .bLength =              USB_DT_ENDPOINT_SIZE,
 264         .bDescriptorType =      USB_DT_ENDPOINT,
 265
 266         .bEndpointAddress =     USB_DIR_OUT,
 267         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 268 };
 269
 270 static struct usb_descriptor_header *ncm_fs_function[] = {
 271         (struct usb_descriptor_header *) &ncm_iad_desc,
 272         /* CDC NCM control descriptors */
 273         (struct usb_descriptor_header *) &ncm_control_intf,
 274         (struct usb_descriptor_header *) &ncm_header_desc,
 275         (struct usb_descriptor_header *) &ncm_union_desc,
 276         (struct usb_descriptor_header *) &ecm_desc,
 277         (struct usb_descriptor_header *) &ncm_desc,
 278         (struct usb_descriptor_header *) &fs_ncm_notify_desc,
 279         /* data interface, altsettings 0 and 1 */
 280         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 281         (struct usb_descriptor_header *) &ncm_data_intf,
 282         (struct usb_descriptor_header *) &fs_ncm_in_desc,
 283         (struct usb_descriptor_header *) &fs_ncm_out_desc,
 284         NULL,
 285 };
 286
 287 /* high speed support: */
 288
 289 static struct usb_endpoint_descriptor hs_ncm_notify_desc = {
 290         .bLength =              USB_DT_ENDPOINT_SIZE,
 291         .bDescriptorType =      USB_DT_ENDPOINT,
 292
 293         .bEndpointAddress =     USB_DIR_IN,
 294         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 295         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 296         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS),
 297 };
 298 static struct usb_endpoint_descriptor hs_ncm_in_desc = {
 299         .bLength =              USB_DT_ENDPOINT_SIZE,
 300         .bDescriptorType =      USB_DT_ENDPOINT,
 301
 302         .bEndpointAddress =     USB_DIR_IN,
 303         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 304         .wMaxPacketSize =       cpu_to_le16(512),
 305 };
 306
 307 static struct usb_endpoint_descriptor hs_ncm_out_desc = {
 308         .bLength =              USB_DT_ENDPOINT_SIZE,
 309         .bDescriptorType =      USB_DT_ENDPOINT,
 310
 311         .bEndpointAddress =     USB_DIR_OUT,
 312         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 313         .wMaxPacketSize =       cpu_to_le16(512),
 314 };
 315
 316 static struct usb_descriptor_header *ncm_hs_function[] = {
 317         (struct usb_descriptor_header *) &ncm_iad_desc,
 318         /* CDC NCM control descriptors */
 319         (struct usb_descriptor_header *) &ncm_control_intf,
 320         (struct usb_descriptor_header *) &ncm_header_desc,
 321         (struct usb_descriptor_header *) &ncm_union_desc,
 322         (struct usb_descriptor_header *) &ecm_desc,
 323         (struct usb_descriptor_header *) &ncm_desc,
 324         (struct usb_descriptor_header *) &hs_ncm_notify_desc,
 325         /* data interface, altsettings 0 and 1 */
 326         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 327         (struct usb_descriptor_header *) &ncm_data_intf,
 328         (struct usb_descriptor_header *) &hs_ncm_in_desc,
 329         (struct usb_descriptor_header *) &hs_ncm_out_desc,
 330         NULL,
 331 };
 332
 333
 334 /* super speed support: */
 335
 336 static struct usb_endpoint_descriptor ss_ncm_notify_desc = {
 337         .bLength =              USB_DT_ENDPOINT_SIZE,
 338         .bDescriptorType =      USB_DT_ENDPOINT,
 339
 340         .bEndpointAddress =     USB_DIR_IN,
 341         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 342         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 343         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS)
 344 };
 345
 346 static struct usb_ss_ep_comp_descriptor ss_ncm_notify_comp_desc = {
 347         .bLength =              sizeof(ss_ncm_notify_comp_desc),
 348         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 349
 350         /* the following 3 values can be tweaked if necessary */
 351         /* .bMaxBurst =         0, */
 352         /* .bmAttributes =      0, */
 353         .wBytesPerInterval =    cpu_to_le16(NCM_STATUS_BYTECOUNT),
 354 };
 355
 356 static struct usb_endpoint_descriptor ss_ncm_in_desc = {
 357         .bLength =              USB_DT_ENDPOINT_SIZE,
 358         .bDescriptorType =      USB_DT_ENDPOINT,
 359
 360         .bEndpointAddress =     USB_DIR_IN,
 361         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 362         .wMaxPacketSize =       cpu_to_le16(1024),
 363 };
 364
 365 static struct usb_endpoint_descriptor ss_ncm_out_desc = {
 366         .bLength =              USB_DT_ENDPOINT_SIZE,
 367         .bDescriptorType =      USB_DT_ENDPOINT,
 368
 369         .bEndpointAddress =     USB_DIR_OUT,
 370         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 371         .wMaxPacketSize =       cpu_to_le16(1024),
 372 };
 373
 374 static struct usb_ss_ep_comp_descriptor ss_ncm_bulk_comp_desc = {
 375         .bLength =              sizeof(ss_ncm_bulk_comp_desc),
 376         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 377
 378         /* the following 2 values can be tweaked if necessary */
 379         .bMaxBurst =            15,
 380         /* .bmAttributes =      0, */
 381 };
 382
 383 static struct usb_descriptor_header *ncm_ss_function[] = {
 384         (struct usb_descriptor_header *) &ncm_iad_desc,
 385         /* CDC NCM control descriptors */
 386         (struct usb_descriptor_header *) &ncm_control_intf,
 387         (struct usb_descriptor_header *) &ncm_header_desc,
 388         (struct usb_descriptor_header *) &ncm_union_desc,
 389         (struct usb_descriptor_header *) &ecm_desc,
 390         (struct usb_descriptor_header *) &ncm_desc,
 391         (struct usb_descriptor_header *) &ss_ncm_notify_desc,
 392         (struct usb_descriptor_header *) &ss_ncm_notify_comp_desc,
 393         /* data interface, altsettings 0 and 1 */
 394         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 395         (struct usb_descriptor_header *) &ncm_data_intf,
 396         (struct usb_descriptor_header *) &ss_ncm_in_desc,
 397         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 398         (struct usb_descriptor_header *) &ss_ncm_out_desc,
 399         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 400         NULL,
 401 };
 402
 403 /* string descriptors: */
 404
 405 #define STRING_CTRL_IDX 0
 406 #define STRING_MAC_IDX  1
 407 #define STRING_DATA_IDX 2
 408 #define STRING_IAD_IDX  3
 409
 410 static struct usb_string ncm_string_defs[] = {
 411         [STRING_CTRL_IDX].s = "CDC Network Control Model (NCM)",
 412         [STRING_MAC_IDX].s = "",
 413         [STRING_DATA_IDX].s = "CDC Network Data",
 414         [STRING_IAD_IDX].s = "CDC NCM",
 415         {  } /* end of list */
 416 };
 417
 418 static struct usb_gadget_strings ncm_string_table = {
 419         .language =             0x0409, /* en-us */
 420         .strings =              ncm_string_defs,
 421 };
 422
 423 static struct usb_gadget_strings *ncm_strings[] = {
 424         &ncm_string_table,
 425         NULL,
 426 };
 427
 428 /*
 429  * Here are options for NCM Datagram Pointer table (NDP) parser.
 430  * There are 2 different formats: NDP16 and NDP32 in the spec (ch. 3),
 431  * in NDP16 offsets and sizes fields are 1 16bit word wide,
 432  * in NDP32 -- 2 16bit words wide. Also signatures are different.
 433  * To make the parser code the same, put the differences in the structure,
 434  * and switch pointers to the structures when the format is changed.
 435  */
 436
 437 struct ndp_parser_opts {
 438         u32             nth_sign;
 439         u32             ndp_sign;
 440         unsigned        nth_size;
 441         unsigned        ndp_size;
 442         unsigned        dpe_size;
 443         unsigned        ndplen_align;
 444         /* sizes in u16 units */
 445         unsigned        dgram_item_len; /* index or length */
 446         unsigned        block_length;
 447         unsigned        ndp_index;
 448         unsigned        reserved1;
 449         unsigned        reserved2;
 450         unsigned        next_ndp_index;
 451 };
 452
 453 #define INIT_NDP16_OPTS {                                       \
 454                 .nth_sign = USB_CDC_NCM_NTH16_SIGN,             \
 455                 .ndp_sign = USB_CDC_NCM_NDP16_NOCRC_SIGN,       \
 456                 .nth_size = sizeof(struct usb_cdc_ncm_nth16),   \
 457                 .ndp_size = sizeof(struct usb_cdc_ncm_ndp16),   \
 458                 .dpe_size = sizeof(struct usb_cdc_ncm_dpe16),   \
 459                 .ndplen_align = 4,                              \
 460                 .dgram_item_len = 1,                            \
 461                 .block_length = 1,                              \
 462                 .ndp_index = 1,                                 \
 463                 .reserved1 = 0,                                 \
 464                 .reserved2 = 0,                                 \
 465                 .next_ndp_index = 1,                            \
 466         }
 467
 468
 469 #define INIT_NDP32_OPTS {                                       \
 470                 .nth_sign = USB_CDC_NCM_NTH32_SIGN,             \
 471                 .ndp_sign = USB_CDC_NCM_NDP32_NOCRC_SIGN,       \
 472                 .nth_size = sizeof(struct usb_cdc_ncm_nth32),   \
 473                 .ndp_size = sizeof(struct usb_cdc_ncm_ndp32),   \
 474                 .dpe_size = sizeof(struct usb_cdc_ncm_dpe32),   \
 475                 .ndplen_align = 8,                              \
 476                 .dgram_item_len = 2,                            \
 477                 .block_length = 2,                              \
 478                 .ndp_index = 2,                                 \
 479                 .reserved1 = 1,                                 \
 480                 .reserved2 = 2,                                 \
 481                 .next_ndp_index = 2,                            \
 482         }
 483
 484 static const struct ndp_parser_opts ndp16_opts = INIT_NDP16_OPTS;
 485 static const struct ndp_parser_opts ndp32_opts = INIT_NDP32_OPTS;
 486
 487 static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
 488 {
 489         switch (size) {
 490         case 1:
 491                 put_unaligned_le16((u16)val, *p);
 492                 break;
 493         case 2:
 494                 put_unaligned_le32((u32)val, *p);
 495
 496                 break;
 497         default:
 498                 BUG();
 499         }
 500
 501         *p += size;
 502 }
 503
 504 static inline unsigned get_ncm(__le16 **p, unsigned size)
 505 {
 506         unsigned tmp;
 507
 508         switch (size) {
 509         case 1:
 510                 tmp = get_unaligned_le16(*p);
 511                 break;
 512         case 2:
 513                 tmp = get_unaligned_le32(*p);
 514                 break;
 515         default:
 516                 BUG();
 517         }
 518
 519         *p += size;
 520         return tmp;
 521 }
 522
 523 /*-------------------------------------------------------------------------*/
 524
 525 static inline void ncm_reset_values(struct f_ncm *ncm)
 526 {
 527         ncm->parser_opts = &ndp16_opts;
 528         ncm->is_crc = false;
 529         ncm->ndp_sign = ncm->parser_opts->ndp_sign;
 530         ncm->port.cdc_filter = DEFAULT_FILTER;
 531
 532         /* doesn't make sense for ncm, fixed size used */
 533         ncm->port.header_len = 0;
 534
 535         ncm->port.fixed_out_len = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
 536         ncm->port.fixed_in_len = NTB_DEFAULT_IN_SIZE;
 537 }
 538
 539 /*
 540  * Context: ncm->lock held
 541  */
 542 static void ncm_do_notify(struct f_ncm *ncm)
 543 {
 544         struct usb_request              *req = ncm->notify_req;
 545         struct usb_cdc_notification     *event;
 546         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 547         __le32                          *data;
 548         int                             status;
 549
 550         /* notification already in flight? */
 551         if (atomic_read(&ncm->notify_count))
 552                 return;
 553
 554         event = req->buf;
 555         switch (ncm->notify_state) {
 556         case NCM_NOTIFY_NONE:
 557                 return;
 558
 559         case NCM_NOTIFY_CONNECT:
 560                 event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
 561                 if (ncm->is_open)
 562                         event->wValue = cpu_to_le16(1);
 563                 else
 564                         event->wValue = cpu_to_le16(0);
 565                 event->wLength = 0;
 566                 req->length = sizeof *event;
 567
 568                 DBG(cdev, "notify connect %s\n",
 569                                 ncm->is_open ? "true" : "false");
 570                 ncm->notify_state = NCM_NOTIFY_NONE;
 571                 break;
 572
 573         case NCM_NOTIFY_SPEED:
 574                 event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
 575                 event->wValue = cpu_to_le16(0);
 576                 event->wLength = cpu_to_le16(8);
 577                 req->length = NCM_STATUS_BYTECOUNT;
 578
 579                 /* SPEED_CHANGE data is up/down speeds in bits/sec */
 580                 data = req->buf + sizeof *event;
 581                 data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));
 582                 data[1] = data[0];
 583
 584                 DBG(cdev, "notify speed %u\n", ncm_bitrate(cdev->gadget));
 585                 ncm->notify_state = NCM_NOTIFY_CONNECT;
 586                 break;
 587         }
 588         event->bmRequestType = 0xA1;
 589         event->wIndex = cpu_to_le16(ncm->ctrl_id);
 590
 591         atomic_inc(&ncm->notify_count);
 592
 593         /*
 594          * In double buffering if there is a space in FIFO,
 595          * completion callback can be called right after the call,
 596          * so unlocking
 597          */
 598         spin_unlock(&ncm->lock);
 599         status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC);
 600         spin_lock(&ncm->lock);
 601         if (status < 0) {
 602                 atomic_dec(&ncm->notify_count);
 603                 DBG(cdev, "notify --> %d\n", status);
 604         }
 605 }
 606
 607 /*
 608  * Context: ncm->lock held
 609  */
 610 static void ncm_notify(struct f_ncm *ncm)
 611 {
 612         /*
 613          * NOTE on most versions of Linux, host side cdc-ethernet
 614          * won't listen for notifications until its netdevice opens.
 615          * The first notification then sits in the FIFO for a long
 616          * time, and the second one is queued.
 617          *
 618          * If ncm_notify() is called before the second (CONNECT)
 619          * notification is sent, then it will reset to send the SPEED
 620          * notificaion again (and again, and again), but it's not a problem
 621          */
 622         ncm->notify_state = NCM_NOTIFY_SPEED;
 623         ncm_do_notify(ncm);
 624 }
 625
 626 static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req)
 627 {
 628         struct f_ncm                    *ncm = req->context;
 629         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 630         struct usb_cdc_notification     *event = req->buf;
 631
 632         spin_lock(&ncm->lock);
 633         switch (req->status) {
 634         case 0:
 635                 VDBG(cdev, "Notification %02x sent\n",
 636                      event->bNotificationType);
 637                 atomic_dec(&ncm->notify_count);
 638                 break;
 639         case -ECONNRESET:
 640         case -ESHUTDOWN:
 641                 atomic_set(&ncm->notify_count, 0);
 642                 ncm->notify_state = NCM_NOTIFY_NONE;
 643                 break;
 644         default:
 645                 DBG(cdev, "event %02x --> %d\n",
 646                         event->bNotificationType, req->status);
 647                 atomic_dec(&ncm->notify_count);
 648                 break;
 649         }
 650         ncm_do_notify(ncm);
 651         spin_unlock(&ncm->lock);
 652 }
 653
 654 static void ncm_ep0out_complete(struct usb_ep *ep, struct usb_request *req)
 655 {
 656         /* now for SET_NTB_INPUT_SIZE only */
 657         unsigned                in_size;
 658         struct usb_function     *f = req->context;
 659         struct f_ncm            *ncm = func_to_ncm(f);
 660         struct usb_composite_dev *cdev = f->config->cdev;
 661
 662         req->context = NULL;
 663         if (req->status || req->actual != req->length) {
 664                 DBG(cdev, "Bad control-OUT transfer\n");
 665                 goto invalid;
 666         }
 667
 668         in_size = get_unaligned_le32(req->buf);
 669         if (in_size < USB_CDC_NCM_NTB_MIN_IN_SIZE ||
 670             in_size > le32_to_cpu(ntb_parameters.dwNtbInMaxSize)) {
 671                 DBG(cdev, "Got wrong INPUT SIZE (%d) from host\n", in_size);
 672                 goto invalid;
 673         }
 674
 675         ncm->port.fixed_in_len = in_size;
 676         VDBG(cdev, "Set NTB INPUT SIZE %d\n", in_size);
 677         return;
 678
 679 invalid:
 680         usb_ep_set_halt(ep);
 681         return;
 682 }
 683
 684 static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 685 {
 686         struct f_ncm            *ncm = func_to_ncm(f);
 687         struct usb_composite_dev *cdev = f->config->cdev;
 688         struct usb_request      *req = cdev->req;
 689         int                     value = -EOPNOTSUPP;
 690         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 691         u16                     w_value = le16_to_cpu(ctrl->wValue);
 692         u16                     w_length = le16_to_cpu(ctrl->wLength);
 693
 694         /*
 695          * composite driver infrastructure handles everything except
 696          * CDC class messages; interface activation uses set_alt().
 697          */
 698         switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 699         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 700                         | USB_CDC_SET_ETHERNET_PACKET_FILTER:
 701                 /*
 702                  * see 6.2.30: no data, wIndex = interface,
 703                  * wValue = packet filter bitmap
 704                  */
 705                 if (w_length != 0 || w_index != ncm->ctrl_id)
 706                         goto invalid;
 707                 DBG(cdev, "packet filter %02x\n", w_value);
 708                 /*
 709                  * REVISIT locking of cdc_filter.  This assumes the UDC
 710                  * driver won't have a concurrent packet TX irq running on
 711                  * another CPU; or that if it does, this write is atomic...
 712                  */
 713                 ncm->port.cdc_filter = w_value;
 714                 value = 0;
 715                 break;
 716         /*
 717          * and optionally:
 718          * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
 719          * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
 720          * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
 721          * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
 722          * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
 723          * case USB_CDC_GET_ETHERNET_STATISTIC:
 724          */
 725
 726         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 727                 | USB_CDC_GET_NTB_PARAMETERS:
 728
 729                 if (w_length == 0 || w_value != 0 || w_index != ncm->ctrl_id)
 730                         goto invalid;
 731                 value = w_length > sizeof ntb_parameters ?
 732                         sizeof ntb_parameters : w_length;
 733                 memcpy(req->buf, &ntb_parameters, value);
 734                 VDBG(cdev, "Host asked NTB parameters\n");
 735                 break;
 736
 737         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 738                 | USB_CDC_GET_NTB_INPUT_SIZE:
 739
 740                 if (w_length < 4 || w_value != 0 || w_index != ncm->ctrl_id)
 741                         goto invalid;
 742                 put_unaligned_le32(ncm->port.fixed_in_len, req->buf);
 743                 value = 4;
 744                 VDBG(cdev, "Host asked INPUT SIZE, sending %d\n",
 745                      ncm->port.fixed_in_len);
 746                 break;
 747
 748         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 749                 | USB_CDC_SET_NTB_INPUT_SIZE:
 750         {
 751                 if (w_length != 4 || w_value != 0 || w_index != ncm->ctrl_id)
 752                         goto invalid;
 753                 req->complete = ncm_ep0out_complete;
 754                 req->length = w_length;
 755                 req->context = f;
 756
 757                 value = req->length;
 758                 break;
 759         }
 760
 761         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 762                 | USB_CDC_GET_NTB_FORMAT:
 763         {
 764                 uint16_t format;
 765
 766                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 767                         goto invalid;
 768                 format = (ncm->parser_opts == &ndp16_opts) ? 0x0000 : 0x0001;
 769                 put_unaligned_le16(format, req->buf);
 770                 value = 2;
 771                 VDBG(cdev, "Host asked NTB FORMAT, sending %d\n", format);
 772                 break;
 773         }
 774
 775         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 776                 | USB_CDC_SET_NTB_FORMAT:
 777         {
 778                 if (w_length != 0 || w_index != ncm->ctrl_id)
 779                         goto invalid;
 780                 switch (w_value) {
 781                 case 0x0000:
 782                         ncm->parser_opts = &ndp16_opts;
 783                         DBG(cdev, "NCM16 selected\n");
 784                         break;
 785                 case 0x0001:
 786                         ncm->parser_opts = &ndp32_opts;
 787                         DBG(cdev, "NCM32 selected\n");
 788                         break;
 789                 default:
 790                         goto invalid;
 791                 }
 792                 value = 0;
 793                 break;
 794         }
 795         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 796                 | USB_CDC_GET_CRC_MODE:
 797         {
 798                 uint16_t is_crc;
 799
 800                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 801                         goto invalid;
 802                 is_crc = ncm->is_crc ? 0x0001 : 0x0000;
 803                 put_unaligned_le16(is_crc, req->buf);
 804                 value = 2;
 805                 VDBG(cdev, "Host asked CRC MODE, sending %d\n", is_crc);
 806                 break;
 807         }
 808
 809         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 810                 | USB_CDC_SET_CRC_MODE:
 811         {
 812                 if (w_length != 0 || w_index != ncm->ctrl_id)
 813                         goto invalid;
 814                 switch (w_value) {
 815                 case 0x0000:
 816                         ncm->is_crc = false;
 817                         DBG(cdev, "non-CRC mode selected\n");
 818                         break;
 819                 case 0x0001:
 820                         ncm->is_crc = true;
 821                         DBG(cdev, "CRC mode selected\n");
 822                         break;
 823                 default:
 824                         goto invalid;
 825                 }
 826                 value = 0;
 827                 break;
 828         }
 829
 830         /* and disabled in ncm descriptor: */
 831         /* case USB_CDC_GET_NET_ADDRESS: */
 832         /* case USB_CDC_SET_NET_ADDRESS: */
 833         /* case USB_CDC_GET_MAX_DATAGRAM_SIZE: */
 834         /* case USB_CDC_SET_MAX_DATAGRAM_SIZE: */
 835
 836         default:
 837 invalid:
 838                 DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 839                         ctrl->bRequestType, ctrl->bRequest,
 840                         w_value, w_index, w_length);
 841         }
 842         ncm->ndp_sign = ncm->parser_opts->ndp_sign |
 843                 (ncm->is_crc ? NCM_NDP_HDR_CRC : 0);
 844
 845         /* respond with data transfer or status phase? */
 846         if (value >= 0) {
 847                 DBG(cdev, "ncm req%02x.%02x v%04x i%04x l%d\n",
 848                         ctrl->bRequestType, ctrl->bRequest,
 849                         w_value, w_index, w_length);
 850                 req->zero = 0;
 851                 req->length = value;
 852                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 853                 if (value < 0)
 854                         ERROR(cdev, "ncm req %02x.%02x response err %d\n",
 855                                         ctrl->bRequestType, ctrl->bRequest,
 856                                         value);
 857         }
 858
 859         /* device either stalls (value < 0) or reports success */
 860         return value;
 861 }
 862
 863
 864 static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 865 {
 866         struct f_ncm            *ncm = func_to_ncm(f);
 867         struct usb_composite_dev *cdev = f->config->cdev;
 868
 869         /* Control interface has only altsetting 0 */
 870         if (intf == ncm->ctrl_id) {
 871                 if (alt != 0)
 872                         goto fail;
 873
 874                 DBG(cdev, "reset ncm control %d\n", intf);
 875                 usb_ep_disable(ncm->notify);
 876
 877                 if (!(ncm->notify->desc)) {
 878                         DBG(cdev, "init ncm ctrl %d\n", intf);
 879                         if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
 880                                 goto fail;
 881                 }
 882                 usb_ep_enable(ncm->notify);
 883
 884         /* Data interface has two altsettings, 0 and 1 */
 885         } else if (intf == ncm->data_id) {
 886                 if (alt > 1)
 887                         goto fail;
 888
 889                 if (ncm->port.in_ep->enabled) {
 890                         DBG(cdev, "reset ncm\n");
 891                         ncm->netdev = NULL;
 892                         gether_disconnect(&ncm->port);
 893                         ncm_reset_values(ncm);
 894                 }
 895
 896                 /*
 897                  * CDC Network only sends data in non-default altsettings.
 898                  * Changing altsettings resets filters, statistics, etc.
 899                  */
 900                 if (alt == 1) {
 901                         struct net_device       *net;
 902
 903                         if (!ncm->port.in_ep->desc ||
 904                             !ncm->port.out_ep->desc) {
 905                                 DBG(cdev, "init ncm\n");
 906                                 if (config_ep_by_speed(cdev->gadget, f,
 907                                                        ncm->port.in_ep) ||
 908                                     config_ep_by_speed(cdev->gadget, f,
 909                                                        ncm->port.out_ep)) {
 910                                         ncm->port.in_ep->desc = NULL;
 911                                         ncm->port.out_ep->desc = NULL;
 912                                         goto fail;
 913                                 }
 914                         }
 915
 916                         /* TODO */
 917                         /* Enable zlps by default for NCM conformance;
 918                          * override for musb_hdrc (avoids txdma ovhead)
 919                          */
 920                         ncm->port.is_zlp_ok =
 921                                 gadget_is_zlp_supported(cdev->gadget);
 922                         ncm->port.cdc_filter = DEFAULT_FILTER;
 923                         DBG(cdev, "activate ncm\n");
 924                         net = gether_connect(&ncm->port);
 925                         if (IS_ERR(net))
 926                                 return PTR_ERR(net);
 927                         ncm->netdev = net;
 928                 }
 929
 930                 spin_lock(&ncm->lock);
 931                 ncm_notify(ncm);
 932                 spin_unlock(&ncm->lock);
 933         } else
 934                 goto fail;
 935
 936         return 0;
 937 fail:
 938         return -EINVAL;
 939 }
 940
 941 /*
 942  * Because the data interface supports multiple altsettings,
 943  * this NCM function *MUST* implement a get_alt() method.
 944  */
 945 static int ncm_get_alt(struct usb_function *f, unsigned intf)
 946 {
 947         struct f_ncm            *ncm = func_to_ncm(f);
 948
 949         if (intf == ncm->ctrl_id)
 950                 return 0;
 951         return ncm->port.in_ep->enabled ? 1 : 0;
 952 }
 953
 954 static struct sk_buff *package_for_tx(struct f_ncm *ncm)
 955 {
 956         __le16          *ntb_iter;
 957         struct sk_buff  *skb2 = NULL;
 958         unsigned        ndp_pad;
 959         unsigned        ndp_index;
 960         unsigned        new_len;
 961
 962         const struct ndp_parser_opts *opts = ncm->parser_opts;
 963         const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
 964         const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
 965
 966         /* Stop the timer */
 967         hrtimer_try_to_cancel(&ncm->task_timer);
 968
 969         ndp_pad = ALIGN(ncm->skb_tx_data->len, ndp_align) -
 970                         ncm->skb_tx_data->len;
 971         ndp_index = ncm->skb_tx_data->len + ndp_pad;
 972         new_len = ndp_index + dgram_idx_len + ncm->skb_tx_ndp->len;
 973
 974         /* Set the final BlockLength and wNdpIndex */
 975         ntb_iter = (void *) ncm->skb_tx_data->data;
 976         /* Increment pointer to BlockLength */
 977         ntb_iter += 2 + 1 + 1;
 978         put_ncm(&ntb_iter, opts->block_length, new_len);
 979         put_ncm(&ntb_iter, opts->ndp_index, ndp_index);
 980
 981         /* Set the final NDP wLength */
 982         new_len = opts->ndp_size +
 983                         (ncm->ndp_dgram_count * dgram_idx_len);
 984         ncm->ndp_dgram_count = 0;
 985         /* Increment from start to wLength */
 986         ntb_iter = (void *) ncm->skb_tx_ndp->data;
 987         ntb_iter += 2;
 988         put_unaligned_le16(new_len, ntb_iter);
 989
 990         /* Merge the skbs */
 991         swap(skb2, ncm->skb_tx_data);
 992         if (ncm->skb_tx_data) {
 993                 dev_consume_skb_any(ncm->skb_tx_data);
 994                 ncm->skb_tx_data = NULL;
 995         }
 996
 997         /* Insert NDP alignment. */
 998         skb_put_zero(skb2, ndp_pad);
 999
1000         /* Copy NTB across. */
1001         skb_put_data(skb2, ncm->skb_tx_ndp->data, ncm->skb_tx_ndp->len);
1002         dev_consume_skb_any(ncm->skb_tx_ndp);
1003         ncm->skb_tx_ndp = NULL;
1004
1005         /* Insert zero'd datagram. */
1006         skb_put_zero(skb2, dgram_idx_len);
1007
1008         return skb2;
1009 }
1010
1011 static struct sk_buff *ncm_wrap_ntb(struct gether *port,
1012                                     struct sk_buff *skb)
1013 {
1014         struct f_ncm    *ncm = func_to_ncm(&port->func);
1015         struct sk_buff  *skb2 = NULL;
1016
1017         if (skb) {
1018                 int             ncb_len = 0;
1019                 __le16          *ntb_data;
1020                 __le16          *ntb_ndp;
1021                 int             dgram_pad;
1022
1023                 unsigned        max_size = ncm->port.fixed_in_len;
1024                 const struct ndp_parser_opts *opts = ncm->parser_opts;
1025                 const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
1026                 const int div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
1027                 const int rem = le16_to_cpu(ntb_parameters.wNdpInPayloadRemainder);
1028                 const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
1029
1030                 /* Add the CRC if required up front */
1031                 if (ncm->is_crc) {
1032                         uint32_t        crc;
1033                         __le16          *crc_pos;
1034
1035                         crc = ~crc32_le(~0,
1036                                         skb->data,
1037                                         skb->len);
1038                         crc_pos = skb_put(skb, sizeof(uint32_t));
1039                         put_unaligned_le32(crc, crc_pos);
1040                 }
1041
1042                 /* If the new skb is too big for the current NCM NTB then
1043                  * set the current stored skb to be sent now and clear it
1044                  * ready for new data.
1045                  * NOTE: Assume maximum align for speed of calculation.
1046                  */
1047                 if (ncm->skb_tx_data
1048                     && (ncm->ndp_dgram_count >= TX_MAX_NUM_DPE
1049                     || (ncm->skb_tx_data->len +
1050                     div + rem + skb->len +
1051                     ncm->skb_tx_ndp->len + ndp_align + (2 * dgram_idx_len))
1052                     > max_size)) {
1053                         skb2 = package_for_tx(ncm);
1054                         if (!skb2)
1055                                 goto err;
1056                 }
1057
1058                 if (!ncm->skb_tx_data) {
1059                         ncb_len = opts->nth_size;
1060                         dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1061                         ncb_len += dgram_pad;
1062
1063                         /* Create a new skb for the NTH and datagrams. */
1064                         ncm->skb_tx_data = alloc_skb(max_size, GFP_ATOMIC);
1065                         if (!ncm->skb_tx_data)
1066                                 goto err;
1067
1068                         ncm->skb_tx_data->dev = ncm->netdev;
1069                         ntb_data = skb_put_zero(ncm->skb_tx_data, ncb_len);
1070                         /* dwSignature */
1071                         put_unaligned_le32(opts->nth_sign, ntb_data);
1072                         ntb_data += 2;
1073                         /* wHeaderLength */
1074                         put_unaligned_le16(opts->nth_size, ntb_data++);
1075
1076                         /* Allocate an skb for storing the NDP,
1077                          * TX_MAX_NUM_DPE should easily suffice for a
1078                          * 16k packet.
1079                          */
1080                         ncm->skb_tx_ndp = alloc_skb((int)(opts->ndp_size
1081                                                     + opts->dpe_size
1082                                                     * TX_MAX_NUM_DPE),
1083                                                     GFP_ATOMIC);
1084                         if (!ncm->skb_tx_ndp)
1085                                 goto err;
1086
1087                         ncm->skb_tx_ndp->dev = ncm->netdev;
1088                         ntb_ndp = skb_put(ncm->skb_tx_ndp, opts->ndp_size);
1089                         memset(ntb_ndp, 0, ncb_len);
1090                         /* dwSignature */
1091                         put_unaligned_le32(ncm->ndp_sign, ntb_ndp);
1092                         ntb_ndp += 2;
1093
1094                         /* There is always a zeroed entry */
1095                         ncm->ndp_dgram_count = 1;
1096
1097                         /* Note: we skip opts->next_ndp_index */
1098
1099                         /* Start the timer. */
1100                         hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
1101                                       HRTIMER_MODE_REL_SOFT);
1102                 }
1103
1104                 /* Add the datagram position entries */
1105                 ntb_ndp = skb_put_zero(ncm->skb_tx_ndp, dgram_idx_len);
1106
1107                 ncb_len = ncm->skb_tx_data->len;
1108                 dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1109                 ncb_len += dgram_pad;
1110
1111                 /* (d)wDatagramIndex */
1112                 put_ncm(&ntb_ndp, opts->dgram_item_len, ncb_len);
1113                 /* (d)wDatagramLength */
1114                 put_ncm(&ntb_ndp, opts->dgram_item_len, skb->len);
1115                 ncm->ndp_dgram_count++;
1116
1117                 /* Add the new data to the skb */
1118                 skb_put_zero(ncm->skb_tx_data, dgram_pad);
1119                 skb_put_data(ncm->skb_tx_data, skb->data, skb->len);
1120                 dev_consume_skb_any(skb);
1121                 skb = NULL;
1122
1123         } else if (ncm->skb_tx_data) {
1124                 /* If we get here ncm_wrap_ntb() was called with NULL skb,
1125                  * because eth_start_xmit() was called with NULL skb by
1126                  * ncm_tx_timeout() - hence, this is our signal to flush/send.
1127                  */
1128                 skb2 = package_for_tx(ncm);
1129                 if (!skb2)
1130                         goto err;
1131         }
1132
1133         return skb2;
1134
1135 err:
1136         ncm->netdev->stats.tx_dropped++;
1137
1138         if (skb)
1139                 dev_kfree_skb_any(skb);
1140         if (ncm->skb_tx_data)
1141                 dev_kfree_skb_any(ncm->skb_tx_data);
1142         if (ncm->skb_tx_ndp)
1143                 dev_kfree_skb_any(ncm->skb_tx_ndp);
1144
1145         return NULL;
1146 }
1147
1148 /*
1149  * The transmit should only be run if no skb data has been sent
1150  * for a certain duration.
1151  */
1152 static enum hrtimer_restart ncm_tx_timeout(struct hrtimer *data)
1153 {
1154         struct f_ncm *ncm = container_of(data, struct f_ncm, task_timer);
1155         struct net_device *netdev = READ_ONCE(ncm->netdev);
1156
1157         if (netdev) {
1158                 /* XXX This allowance of a NULL skb argument to ndo_start_xmit
1159                  * XXX is not sane.  The gadget layer should be redesigned so
1160                  * XXX that the dev->wrap() invocations to build SKBs is transparent
1161                  * XXX and performed in some way outside of the ndo_start_xmit
1162                  * XXX interface.
1163                  *
1164                  * This will call directly into u_ether's eth_start_xmit()
1165                  */
1166                 netdev->netdev_ops->ndo_start_xmit(NULL, netdev);
1167         }
1168         return HRTIMER_NORESTART;
1169 }
1170
1171 static int ncm_unwrap_ntb(struct gether *port,
1172                           struct sk_buff *skb,
1173                           struct sk_buff_head *list)
1174 {
1175         struct f_ncm    *ncm = func_to_ncm(&port->func);
1176         __le16          *tmp = (void *) skb->data;
1177         unsigned        index, index2;
1178         int             ndp_index;
1179         unsigned        dg_len, dg_len2;
1180         unsigned        ndp_len;
1181         unsigned        block_len;
1182         struct sk_buff  *skb2;
1183         int             ret = -EINVAL;
1184         unsigned        ntb_max = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
1185         unsigned        frame_max = le16_to_cpu(ecm_desc.wMaxSegmentSize);
1186         const struct ndp_parser_opts *opts = ncm->parser_opts;
1187         unsigned        crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
1188         int             dgram_counter;
1189
1190         /* dwSignature */
1191         if (get_unaligned_le32(tmp) != opts->nth_sign) {
1192                 INFO(port->func.config->cdev, "Wrong NTH SIGN, skblen %d\n",
1193                         skb->len);
1194                 print_hex_dump(KERN_INFO, "HEAD:", DUMP_PREFIX_ADDRESS, 32, 1,
1195                                skb->data, 32, false);
1196
1197                 goto err;
1198         }
1199         tmp += 2;
1200         /* wHeaderLength */
1201         if (get_unaligned_le16(tmp++) != opts->nth_size) {
1202                 INFO(port->func.config->cdev, "Wrong NTB headersize\n");
1203                 goto err;
1204         }
1205         tmp++; /* skip wSequence */
1206
1207         block_len = get_ncm(&tmp, opts->block_length);
1208         /* (d)wBlockLength */
1209         if (block_len > ntb_max) {
1210                 INFO(port->func.config->cdev, "OUT size exceeded\n");
1211                 goto err;
1212         }
1213
1214         ndp_index = get_ncm(&tmp, opts->ndp_index);
1215
1216         /* Run through all the NDP's in the NTB */
1217         do {
1218                 /*
1219                  * NCM 3.2
1220                  * dwNdpIndex
1221                  */
1222                 if (((ndp_index % 4) != 0) ||
1223                                 (ndp_index < opts->nth_size) ||
1224                                 (ndp_index > (block_len -
1225                                               opts->ndp_size))) {
1226                         INFO(port->func.config->cdev, "Bad index: %#X\n",
1227                              ndp_index);
1228                         goto err;
1229                 }
1230
1231                 /*
1232                  * walk through NDP
1233                  * dwSignature
1234                  */
1235                 tmp = (void *)(skb->data + ndp_index);
1236                 if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
1237                         INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
1238                         goto err;
1239                 }
1240                 tmp += 2;
1241
1242                 ndp_len = get_unaligned_le16(tmp++);
1243                 /*
1244                  * NCM 3.3.1
1245                  * wLength
1246                  * entry is 2 items
1247                  * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
1248                  * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
1249                  * Each entry is a dgram index and a dgram length.
1250                  */
1251                 if ((ndp_len < opts->ndp_size
1252                                 + 2 * 2 * (opts->dgram_item_len * 2)) ||
1253                                 (ndp_len % opts->ndplen_align != 0)) {
1254                         INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
1255                              ndp_len);
1256                         goto err;
1257                 }
1258                 tmp += opts->reserved1;
1259                 /* Check for another NDP (d)wNextNdpIndex */
1260                 ndp_index = get_ncm(&tmp, opts->next_ndp_index);
1261                 tmp += opts->reserved2;
1262
1263                 ndp_len -= opts->ndp_size;
1264                 index2 = get_ncm(&tmp, opts->dgram_item_len);
1265                 dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1266                 dgram_counter = 0;
1267
1268                 do {
1269                         index = index2;
1270                         /* wDatagramIndex[0] */
1271                         if ((index < opts->nth_size) ||
1272                                         (index > block_len - opts->dpe_size)) {
1273                                 INFO(port->func.config->cdev,
1274                                      "Bad index: %#X\n", index);
1275                                 goto err;
1276                         }
1277
1278                         dg_len = dg_len2;
1279                         /*
1280                          * wDatagramLength[0]
1281                          * ethernet hdr + crc or larger than max frame size
1282                          */
1283                         if ((dg_len < 14 + crc_len) ||
1284                                         (dg_len > frame_max)) {
1285                                 INFO(port->func.config->cdev,
1286                                      "Bad dgram length: %#X\n", dg_len);
1287                                 goto err;
1288                         }
1289                         if (ncm->is_crc) {
1290                                 uint32_t crc, crc2;
1291
1292                                 crc = get_unaligned_le32(skb->data +
1293                                                          index + dg_len -
1294                                                          crc_len);
1295                                 crc2 = ~crc32_le(~0,
1296                                                  skb->data + index,
1297                                                  dg_len - crc_len);
1298                                 if (crc != crc2) {
1299                                         INFO(port->func.config->cdev,
1300                                              "Bad CRC\n");
1301                                         goto err;
1302                                 }
1303                         }
1304
1305                         index2 = get_ncm(&tmp, opts->dgram_item_len);
1306                         dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1307
1308                         /* wDatagramIndex[1] */
1309                         if (index2 > block_len - opts->dpe_size) {
1310                                 INFO(port->func.config->cdev,
1311                                      "Bad index: %#X\n", index2);
1312                                 goto err;
1313                         }
1314
1315                         /*
1316                          * Copy the data into a new skb.
1317                          * This ensures the truesize is correct
1318                          */
1319                         skb2 = netdev_alloc_skb_ip_align(ncm->netdev,
1320                                                          dg_len - crc_len);
1321                         if (skb2 == NULL)
1322                                 goto err;
1323                         skb_put_data(skb2, skb->data + index,
1324                                      dg_len - crc_len);
1325
1326                         skb_queue_tail(list, skb2);
1327
1328                         ndp_len -= 2 * (opts->dgram_item_len * 2);
1329
1330                         dgram_counter++;
1331                         if (index2 == 0 || dg_len2 == 0)
1332                                 break;
1333                 } while (ndp_len > 2 * (opts->dgram_item_len * 2));
1334         } while (ndp_index);
1335
1336         dev_consume_skb_any(skb);
1337
1338         VDBG(port->func.config->cdev,
1339              "Parsed NTB with %d frames\n", dgram_counter);
1340         return 0;
1341 err:
1342         skb_queue_purge(list);
1343         dev_kfree_skb_any(skb);
1344         return ret;
1345 }
1346
1347 static void ncm_disable(struct usb_function *f)
1348 {
1349         struct f_ncm            *ncm = func_to_ncm(f);
1350         struct usb_composite_dev *cdev = f->config->cdev;
1351
1352         DBG(cdev, "ncm deactivated\n");
1353
1354         if (ncm->port.in_ep->enabled) {
1355                 ncm->netdev = NULL;
1356                 gether_disconnect(&ncm->port);
1357         }
1358
1359         if (ncm->notify->enabled) {
1360                 usb_ep_disable(ncm->notify);
1361                 ncm->notify->desc = NULL;
1362         }
1363 }
1364
1365 /*-------------------------------------------------------------------------*/
1366
1367 /*
1368  * Callbacks let us notify the host about connect/disconnect when the
1369  * net device is opened or closed.
1370  *
1371  * For testing, note that link states on this side include both opened
1372  * and closed variants of:
1373  *
1374  *   - disconnected/unconfigured
1375  *   - configured but inactive (data alt 0)
1376  *   - configured and active (data alt 1)
1377  *
1378  * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
1379  * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
1380  * imply the host is actually polling the notification endpoint, and
1381  * likewise that "active" doesn't imply it's actually using the data
1382  * endpoints for traffic.
1383  */
1384
1385 static void ncm_open(struct gether *geth)
1386 {
1387         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1388
1389         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1390
1391         spin_lock(&ncm->lock);
1392         ncm->is_open = true;
1393         ncm_notify(ncm);
1394         spin_unlock(&ncm->lock);
1395 }
1396
1397 static void ncm_close(struct gether *geth)
1398 {
1399         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1400
1401         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1402
1403         spin_lock(&ncm->lock);
1404         ncm->is_open = false;
1405         ncm_notify(ncm);
1406         spin_unlock(&ncm->lock);
1407 }
1408
1409 /*-------------------------------------------------------------------------*/
1410
1411 /* ethernet function driver setup/binding */
1412
1413 static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
1414 {
1415         struct usb_composite_dev *cdev = c->cdev;
1416         struct f_ncm            *ncm = func_to_ncm(f);
1417         struct usb_string       *us;
1418         int                     status;
1419         struct usb_ep           *ep;
1420         struct f_ncm_opts       *ncm_opts;
1421
1422         if (!can_support_ecm(cdev->gadget))
1423                 return -EINVAL;
1424
1425         ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1426
1427         if (cdev->use_os_string) {
1428                 f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
1429                                            GFP_KERNEL);
1430                 if (!f->os_desc_table)
1431                         return -ENOMEM;
1432                 f->os_desc_n = 1;
1433                 f->os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
1434         }
1435
1436         /*
1437          * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
1438          * configurations are bound in sequence with list_for_each_entry,
1439          * in each configuration its functions are bound in sequence
1440          * with list_for_each_entry, so we assume no race condition
1441          * with regard to ncm_opts->bound access
1442          */
1443         if (!ncm_opts->bound) {
1444                 mutex_lock(&ncm_opts->lock);
1445                 gether_set_gadget(ncm_opts->net, cdev->gadget);
1446                 status = gether_register_netdev(ncm_opts->net);
1447                 mutex_unlock(&ncm_opts->lock);
1448                 if (status)
1449                         goto fail;
1450                 ncm_opts->bound = true;
1451         }
1452         us = usb_gstrings_attach(cdev, ncm_strings,
1453                                  ARRAY_SIZE(ncm_string_defs));
1454         if (IS_ERR(us)) {
1455                 status = PTR_ERR(us);
1456                 goto fail;
1457         }
1458         ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
1459         ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
1460         ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
1461         ecm_desc.iMACAddress = us[STRING_MAC_IDX].id;
1462         ncm_iad_desc.iFunction = us[STRING_IAD_IDX].id;
1463
1464         /* allocate instance-specific interface IDs */
1465         status = usb_interface_id(c, f);
1466         if (status < 0)
1467                 goto fail;
1468         ncm->ctrl_id = status;
1469         ncm_iad_desc.bFirstInterface = status;
1470
1471         ncm_control_intf.bInterfaceNumber = status;
1472         ncm_union_desc.bMasterInterface0 = status;
1473
1474         if (cdev->use_os_string)
1475                 f->os_desc_table[0].if_id =
1476                         ncm_iad_desc.bFirstInterface;
1477
1478         status = usb_interface_id(c, f);
1479         if (status < 0)
1480                 goto fail;
1481         ncm->data_id = status;
1482
1483         ncm_data_nop_intf.bInterfaceNumber = status;
1484         ncm_data_intf.bInterfaceNumber = status;
1485         ncm_union_desc.bSlaveInterface0 = status;
1486
1487         status = -ENODEV;
1488
1489         /* allocate instance-specific endpoints */
1490         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
1491         if (!ep)
1492                 goto fail;
1493         ncm->port.in_ep = ep;
1494
1495         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
1496         if (!ep)
1497                 goto fail;
1498         ncm->port.out_ep = ep;
1499
1500         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
1501         if (!ep)
1502                 goto fail;
1503         ncm->notify = ep;
1504
1505         status = -ENOMEM;
1506
1507         /* allocate notification request and buffer */
1508         ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
1509         if (!ncm->notify_req)
1510                 goto fail;
1511         ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
1512         if (!ncm->notify_req->buf)
1513                 goto fail;
1514         ncm->notify_req->context = ncm;
1515         ncm->notify_req->complete = ncm_notify_complete;
1516
1517         /*
1518          * support all relevant hardware speeds... we expect that when
1519          * hardware is dual speed, all bulk-capable endpoints work at
1520          * both speeds
1521          */
1522         hs_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1523         hs_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1524         hs_ncm_notify_desc.bEndpointAddress =
1525                 fs_ncm_notify_desc.bEndpointAddress;
1526
1527         ss_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1528         ss_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1529         ss_ncm_notify_desc.bEndpointAddress =
1530                 fs_ncm_notify_desc.bEndpointAddress;
1531
1532         status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
1533                         ncm_ss_function, ncm_ss_function);
1534         if (status)
1535                 goto fail;
1536
1537         /*
1538          * NOTE:  all that is done without knowing or caring about
1539          * the network link ... which is unavailable to this code
1540          * until we're activated via set_alt().
1541          */
1542
1543         ncm->port.open = ncm_open;
1544         ncm->port.close = ncm_close;
1545
1546         hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
1547         ncm->task_timer.function = ncm_tx_timeout;
1548
1549         DBG(cdev, "CDC Network: %s speed IN/%s OUT/%s NOTIFY/%s\n",
1550                         gadget_is_superspeed(c->cdev->gadget) ? "super" :
1551                         gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
1552                         ncm->port.in_ep->name, ncm->port.out_ep->name,
1553                         ncm->notify->name);
1554         return 0;
1555
1556 fail:
1557         kfree(f->os_desc_table);
1558         f->os_desc_n = 0;
1559
1560         if (ncm->notify_req) {
1561                 kfree(ncm->notify_req->buf);
1562                 usb_ep_free_request(ncm->notify, ncm->notify_req);
1563         }
1564
1565         ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1566
1567         return status;
1568 }
1569
1570 static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
1571 {
1572         return container_of(to_config_group(item), struct f_ncm_opts,
1573                             func_inst.group);
1574 }
1575
1576 /* f_ncm_item_ops */
1577 USB_ETHERNET_CONFIGFS_ITEM(ncm);
1578
1579 /* f_ncm_opts_dev_addr */
1580 USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
1581
1582 /* f_ncm_opts_host_addr */
1583 USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
1584
1585 /* f_ncm_opts_qmult */
1586 USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
1587
1588 /* f_ncm_opts_ifname */
1589 USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
1590
1591 static struct configfs_attribute *ncm_attrs[] = {
1592         &ncm_opts_attr_dev_addr,
1593         &ncm_opts_attr_host_addr,
1594         &ncm_opts_attr_qmult,
1595         &ncm_opts_attr_ifname,
1596         NULL,
1597 };
1598
1599 static const struct config_item_type ncm_func_type = {
1600         .ct_item_ops    = &ncm_item_ops,
1601         .ct_attrs       = ncm_attrs,
1602         .ct_owner       = THIS_MODULE,
1603 };
1604
1605 static void ncm_free_inst(struct usb_function_instance *f)
1606 {
1607         struct f_ncm_opts *opts;
1608
1609         opts = container_of(f, struct f_ncm_opts, func_inst);
1610         if (opts->bound)
1611                 gether_cleanup(netdev_priv(opts->net));
1612         else
1613                 free_netdev(opts->net);
1614         kfree(opts->ncm_interf_group);
1615         kfree(opts);
1616 }
1617
1618 static struct usb_function_instance *ncm_alloc_inst(void)
1619 {
1620         struct f_ncm_opts *opts;
1621         struct usb_os_desc *descs[1];
1622         char *names[1];
1623         struct config_group *ncm_interf_group;
1624
1625         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1626         if (!opts)
1627                 return ERR_PTR(-ENOMEM);
1628         opts->ncm_os_desc.ext_compat_id = opts->ncm_ext_compat_id;
1629
1630         mutex_init(&opts->lock);
1631         opts->func_inst.free_func_inst = ncm_free_inst;
1632         opts->net = gether_setup_default();
1633         if (IS_ERR(opts->net)) {
1634                 struct net_device *net = opts->net;
1635                 kfree(opts);
1636                 return ERR_CAST(net);
1637         }
1638         INIT_LIST_HEAD(&opts->ncm_os_desc.ext_prop);
1639
1640         descs[0] = &opts->ncm_os_desc;
1641         names[0] = "ncm";
1642
1643         config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type);
1644         ncm_interf_group =
1645                 usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
1646                                                names, THIS_MODULE);
1647         if (IS_ERR(ncm_interf_group)) {
1648                 ncm_free_inst(&opts->func_inst);
1649                 return ERR_CAST(ncm_interf_group);
1650         }
1651         opts->ncm_interf_group = ncm_interf_group;
1652
1653         return &opts->func_inst;
1654 }
1655
1656 static void ncm_free(struct usb_function *f)
1657 {
1658         struct f_ncm *ncm;
1659         struct f_ncm_opts *opts;
1660
1661         ncm = func_to_ncm(f);
1662         opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1663         kfree(ncm);
1664         mutex_lock(&opts->lock);
1665         opts->refcnt--;
1666         mutex_unlock(&opts->lock);
1667 }
1668
1669 static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
1670 {
1671         struct f_ncm *ncm = func_to_ncm(f);
1672
1673         DBG(c->cdev, "ncm unbind\n");
1674
1675         hrtimer_cancel(&ncm->task_timer);
1676
1677         kfree(f->os_desc_table);
1678         f->os_desc_n = 0;
1679
1680         ncm_string_defs[0].id = 0;
1681         usb_free_all_descriptors(f);
1682
1683         if (atomic_read(&ncm->notify_count)) {
1684                 usb_ep_dequeue(ncm->notify, ncm->notify_req);
1685                 atomic_set(&ncm->notify_count, 0);
1686         }
1687
1688         kfree(ncm->notify_req->buf);
1689         usb_ep_free_request(ncm->notify, ncm->notify_req);
1690 }
1691
1692 static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
1693 {
1694         struct f_ncm            *ncm;
1695         struct f_ncm_opts       *opts;
1696         int status;
1697
1698         /* allocate and initialize one new instance */
1699         ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);
1700         if (!ncm)
1701                 return ERR_PTR(-ENOMEM);
1702
1703         opts = container_of(fi, struct f_ncm_opts, func_inst);
1704         mutex_lock(&opts->lock);
1705         opts->refcnt++;
1706
1707         /* export host's Ethernet address in CDC format */
1708         status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
1709                                       sizeof(ncm->ethaddr));
1710         if (status < 12) { /* strlen("01234567890a") */
1711                 kfree(ncm);
1712                 mutex_unlock(&opts->lock);
1713                 return ERR_PTR(-EINVAL);
1714         }
1715         ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
1716
1717         spin_lock_init(&ncm->lock);
1718         ncm_reset_values(ncm);
1719         ncm->port.ioport = netdev_priv(opts->net);
1720         mutex_unlock(&opts->lock);
1721         ncm->port.is_fixed = true;
1722         ncm->port.supports_multi_frame = true;
1723
1724         ncm->port.func.name = "cdc_network";
1725         /* descriptors are per-instance copies */
1726         ncm->port.func.bind = ncm_bind;
1727         ncm->port.func.unbind = ncm_unbind;
1728         ncm->port.func.set_alt = ncm_set_alt;
1729         ncm->port.func.get_alt = ncm_get_alt;
1730         ncm->port.func.setup = ncm_setup;
1731         ncm->port.func.disable = ncm_disable;
1732         ncm->port.func.free_func = ncm_free;
1733
1734         ncm->port.wrap = ncm_wrap_ntb;
1735         ncm->port.unwrap = ncm_unwrap_ntb;
1736
1737         return &ncm->port.func;
1738 }
1739
1740 DECLARE_USB_FUNCTION_INIT(ncm, ncm_alloc_inst, ncm_alloc);
1741 MODULE_LICENSE("GPL");
1742 MODULE_AUTHOR("Yauheni Kaliuta");