drivers/usb/gadget/function/f_ncm.c

   1 /*
   2  * f_ncm.c -- USB CDC Network (NCM) link function driver
   3  *
   4  * Copyright (C) 2010 Nokia Corporation
   5  * Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com>
   6  *
   7  * The driver borrows from f_ecm.c which is:
   8  *
   9  * Copyright (C) 2003-2005,2008 David Brownell
  10  * Copyright (C) 2008 Nokia Corporation
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/device.h>
  21 #include <linux/etherdevice.h>
  22 #include <linux/crc32.h>
  23
  24 #include <linux/usb/cdc.h>
  25
  26 #include "u_ether.h"
  27 #include "u_ether_configfs.h"
  28 #include "u_ncm.h"
  29
  30 /*
  31  * This function is a "CDC Network Control Model" (CDC NCM) Ethernet link.
  32  * NCM is intended to be used with high-speed network attachments.
  33  *
  34  * Note that NCM requires the use of "alternate settings" for its data
  35  * interface.  This means that the set_alt() method has real work to do,
  36  * and also means that a get_alt() method is required.
  37  */
  38
  39 /* to trigger crc/non-crc ndp signature */
  40
  41 #define NCM_NDP_HDR_CRC_MASK    0x01000000
  42 #define NCM_NDP_HDR_CRC         0x01000000
  43 #define NCM_NDP_HDR_NOCRC       0x00000000
  44
  45 enum ncm_notify_state {
  46         NCM_NOTIFY_NONE,                /* don't notify */
  47         NCM_NOTIFY_CONNECT,             /* issue CONNECT next */
  48         NCM_NOTIFY_SPEED,               /* issue SPEED_CHANGE next */
  49 };
  50
  51 struct f_ncm {
  52         struct gether                   port;
  53         u8                              ctrl_id, data_id;
  54
  55         char                            ethaddr[14];
  56
  57         struct usb_ep                   *notify;
  58         struct usb_request              *notify_req;
  59         u8                              notify_state;
  60         bool                            is_open;
  61
  62         const struct ndp_parser_opts    *parser_opts;
  63         bool                            is_crc;
  64         u32                             ndp_sign;
  65
  66         /*
  67          * for notification, it is accessed from both
  68          * callback and ethernet open/close
  69          */
  70         spinlock_t                      lock;
  71
  72         struct net_device               *netdev;
  73
  74         /* For multi-frame NDP TX */
  75         struct sk_buff                  *skb_tx_data;
  76         struct sk_buff                  *skb_tx_ndp;
  77         u16                             ndp_dgram_count;
  78         bool                            timer_force_tx;
  79         struct tasklet_struct           tx_tasklet;
  80         struct hrtimer                  task_timer;
  81
  82         bool                            timer_stopping;
  83 };
  84
  85 static inline struct f_ncm *func_to_ncm(struct usb_function *f)
  86 {
  87         return container_of(f, struct f_ncm, port.func);
  88 }
  89
  90 /* peak (theoretical) bulk transfer rate in bits-per-second */
  91 static inline unsigned ncm_bitrate(struct usb_gadget *g)
  92 {
  93         if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
  94                 return 13 * 1024 * 8 * 1000 * 8;
  95         else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
  96                 return 13 * 512 * 8 * 1000 * 8;
  97         else
  98                 return 19 *  64 * 1 * 1000 * 8;
  99 }
 100
 101 /*-------------------------------------------------------------------------*/
 102
 103 /*
 104  * We cannot group frames so use just the minimal size which ok to put
 105  * one max-size ethernet frame.
 106  * If the host can group frames, allow it to do that, 16K is selected,
 107  * because it's used by default by the current linux host driver
 108  */
 109 #define NTB_DEFAULT_IN_SIZE     16384
 110 #define NTB_OUT_SIZE            16384
 111
 112 /* Allocation for storing the NDP, 32 should suffice for a
 113  * 16k packet. This allows a maximum of 32 * 507 Byte packets to
 114  * be transmitted in a single 16kB skb, though when sending full size
 115  * packets this limit will be plenty.
 116  * Smaller packets are not likely to be trying to maximize the
 117  * throughput and will be mstly sending smaller infrequent frames.
 118  */
 119 #define TX_MAX_NUM_DPE          32
 120
 121 /* Delay for the transmit to wait before sending an unfilled NTB frame. */
 122 #define TX_TIMEOUT_NSECS        300000
 123
 124 #define FORMATS_SUPPORTED       (USB_CDC_NCM_NTB16_SUPPORTED |  \
 125                                  USB_CDC_NCM_NTB32_SUPPORTED)
 126
 127 static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
 128         .wLength = cpu_to_le16(sizeof(ntb_parameters)),
 129         .bmNtbFormatsSupported = cpu_to_le16(FORMATS_SUPPORTED),
 130         .dwNtbInMaxSize = cpu_to_le32(NTB_DEFAULT_IN_SIZE),
 131         .wNdpInDivisor = cpu_to_le16(4),
 132         .wNdpInPayloadRemainder = cpu_to_le16(0),
 133         .wNdpInAlignment = cpu_to_le16(4),
 134
 135         .dwNtbOutMaxSize = cpu_to_le32(NTB_OUT_SIZE),
 136         .wNdpOutDivisor = cpu_to_le16(4),
 137         .wNdpOutPayloadRemainder = cpu_to_le16(0),
 138         .wNdpOutAlignment = cpu_to_le16(4),
 139 };
 140
 141 /*
 142  * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
 143  * packet, to simplify cancellation; and a big transfer interval, to
 144  * waste less bandwidth.
 145  */
 146
 147 #define NCM_STATUS_INTERVAL_MS          32
 148 #define NCM_STATUS_BYTECOUNT            16      /* 8 byte header + data */
 149
 150 static struct usb_interface_assoc_descriptor ncm_iad_desc = {
 151         .bLength =              sizeof ncm_iad_desc,
 152         .bDescriptorType =      USB_DT_INTERFACE_ASSOCIATION,
 153
 154         /* .bFirstInterface =   DYNAMIC, */
 155         .bInterfaceCount =      2,      /* control + data */
 156         .bFunctionClass =       USB_CLASS_COMM,
 157         .bFunctionSubClass =    USB_CDC_SUBCLASS_NCM,
 158         .bFunctionProtocol =    USB_CDC_PROTO_NONE,
 159         /* .iFunction =         DYNAMIC */
 160 };
 161
 162 /* interface descriptor: */
 163
 164 static struct usb_interface_descriptor ncm_control_intf = {
 165         .bLength =              sizeof ncm_control_intf,
 166         .bDescriptorType =      USB_DT_INTERFACE,
 167
 168         /* .bInterfaceNumber = DYNAMIC */
 169         .bNumEndpoints =        1,
 170         .bInterfaceClass =      USB_CLASS_COMM,
 171         .bInterfaceSubClass =   USB_CDC_SUBCLASS_NCM,
 172         .bInterfaceProtocol =   USB_CDC_PROTO_NONE,
 173         /* .iInterface = DYNAMIC */
 174 };
 175
 176 static struct usb_cdc_header_desc ncm_header_desc = {
 177         .bLength =              sizeof ncm_header_desc,
 178         .bDescriptorType =      USB_DT_CS_INTERFACE,
 179         .bDescriptorSubType =   USB_CDC_HEADER_TYPE,
 180
 181         .bcdCDC =               cpu_to_le16(0x0110),
 182 };
 183
 184 static struct usb_cdc_union_desc ncm_union_desc = {
 185         .bLength =              sizeof(ncm_union_desc),
 186         .bDescriptorType =      USB_DT_CS_INTERFACE,
 187         .bDescriptorSubType =   USB_CDC_UNION_TYPE,
 188         /* .bMasterInterface0 = DYNAMIC */
 189         /* .bSlaveInterface0 =  DYNAMIC */
 190 };
 191
 192 static struct usb_cdc_ether_desc ecm_desc = {
 193         .bLength =              sizeof ecm_desc,
 194         .bDescriptorType =      USB_DT_CS_INTERFACE,
 195         .bDescriptorSubType =   USB_CDC_ETHERNET_TYPE,
 196
 197         /* this descriptor actually adds value, surprise! */
 198         /* .iMACAddress = DYNAMIC */
 199         .bmEthernetStatistics = cpu_to_le32(0), /* no statistics */
 200         .wMaxSegmentSize =      cpu_to_le16(ETH_FRAME_LEN),
 201         .wNumberMCFilters =     cpu_to_le16(0),
 202         .bNumberPowerFilters =  0,
 203 };
 204
 205 #define NCAPS   (USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
 206
 207 static struct usb_cdc_ncm_desc ncm_desc = {
 208         .bLength =              sizeof ncm_desc,
 209         .bDescriptorType =      USB_DT_CS_INTERFACE,
 210         .bDescriptorSubType =   USB_CDC_NCM_TYPE,
 211
 212         .bcdNcmVersion =        cpu_to_le16(0x0100),
 213         /* can process SetEthernetPacketFilter */
 214         .bmNetworkCapabilities = NCAPS,
 215 };
 216
 217 /* the default data interface has no endpoints ... */
 218
 219 static struct usb_interface_descriptor ncm_data_nop_intf = {
 220         .bLength =              sizeof ncm_data_nop_intf,
 221         .bDescriptorType =      USB_DT_INTERFACE,
 222
 223         .bInterfaceNumber =     1,
 224         .bAlternateSetting =    0,
 225         .bNumEndpoints =        0,
 226         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 227         .bInterfaceSubClass =   0,
 228         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 229         /* .iInterface = DYNAMIC */
 230 };
 231
 232 /* ... but the "real" data interface has two bulk endpoints */
 233
 234 static struct usb_interface_descriptor ncm_data_intf = {
 235         .bLength =              sizeof ncm_data_intf,
 236         .bDescriptorType =      USB_DT_INTERFACE,
 237
 238         .bInterfaceNumber =     1,
 239         .bAlternateSetting =    1,
 240         .bNumEndpoints =        2,
 241         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 242         .bInterfaceSubClass =   0,
 243         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 244         /* .iInterface = DYNAMIC */
 245 };
 246
 247 /* full speed support: */
 248
 249 static struct usb_endpoint_descriptor fs_ncm_notify_desc = {
 250         .bLength =              USB_DT_ENDPOINT_SIZE,
 251         .bDescriptorType =      USB_DT_ENDPOINT,
 252
 253         .bEndpointAddress =     USB_DIR_IN,
 254         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 255         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 256         .bInterval =            NCM_STATUS_INTERVAL_MS,
 257 };
 258
 259 static struct usb_endpoint_descriptor fs_ncm_in_desc = {
 260         .bLength =              USB_DT_ENDPOINT_SIZE,
 261         .bDescriptorType =      USB_DT_ENDPOINT,
 262
 263         .bEndpointAddress =     USB_DIR_IN,
 264         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 265 };
 266
 267 static struct usb_endpoint_descriptor fs_ncm_out_desc = {
 268         .bLength =              USB_DT_ENDPOINT_SIZE,
 269         .bDescriptorType =      USB_DT_ENDPOINT,
 270
 271         .bEndpointAddress =     USB_DIR_OUT,
 272         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 273 };
 274
 275 static struct usb_descriptor_header *ncm_fs_function[] = {
 276         (struct usb_descriptor_header *) &ncm_iad_desc,
 277         /* CDC NCM control descriptors */
 278         (struct usb_descriptor_header *) &ncm_control_intf,
 279         (struct usb_descriptor_header *) &ncm_header_desc,
 280         (struct usb_descriptor_header *) &ncm_union_desc,
 281         (struct usb_descriptor_header *) &ecm_desc,
 282         (struct usb_descriptor_header *) &ncm_desc,
 283         (struct usb_descriptor_header *) &fs_ncm_notify_desc,
 284         /* data interface, altsettings 0 and 1 */
 285         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 286         (struct usb_descriptor_header *) &ncm_data_intf,
 287         (struct usb_descriptor_header *) &fs_ncm_in_desc,
 288         (struct usb_descriptor_header *) &fs_ncm_out_desc,
 289         NULL,
 290 };
 291
 292 /* high speed support: */
 293
 294 static struct usb_endpoint_descriptor hs_ncm_notify_desc = {
 295         .bLength =              USB_DT_ENDPOINT_SIZE,
 296         .bDescriptorType =      USB_DT_ENDPOINT,
 297
 298         .bEndpointAddress =     USB_DIR_IN,
 299         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 300         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 301         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS),
 302 };
 303 static struct usb_endpoint_descriptor hs_ncm_in_desc = {
 304         .bLength =              USB_DT_ENDPOINT_SIZE,
 305         .bDescriptorType =      USB_DT_ENDPOINT,
 306
 307         .bEndpointAddress =     USB_DIR_IN,
 308         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 309         .wMaxPacketSize =       cpu_to_le16(512),
 310 };
 311
 312 static struct usb_endpoint_descriptor hs_ncm_out_desc = {
 313         .bLength =              USB_DT_ENDPOINT_SIZE,
 314         .bDescriptorType =      USB_DT_ENDPOINT,
 315
 316         .bEndpointAddress =     USB_DIR_OUT,
 317         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 318         .wMaxPacketSize =       cpu_to_le16(512),
 319 };
 320
 321 static struct usb_descriptor_header *ncm_hs_function[] = {
 322         (struct usb_descriptor_header *) &ncm_iad_desc,
 323         /* CDC NCM control descriptors */
 324         (struct usb_descriptor_header *) &ncm_control_intf,
 325         (struct usb_descriptor_header *) &ncm_header_desc,
 326         (struct usb_descriptor_header *) &ncm_union_desc,
 327         (struct usb_descriptor_header *) &ecm_desc,
 328         (struct usb_descriptor_header *) &ncm_desc,
 329         (struct usb_descriptor_header *) &hs_ncm_notify_desc,
 330         /* data interface, altsettings 0 and 1 */
 331         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 332         (struct usb_descriptor_header *) &ncm_data_intf,
 333         (struct usb_descriptor_header *) &hs_ncm_in_desc,
 334         (struct usb_descriptor_header *) &hs_ncm_out_desc,
 335         NULL,
 336 };
 337
 338
 339 /* super speed support: */
 340
 341 static struct usb_endpoint_descriptor ss_ncm_notify_desc = {
 342         .bLength =              USB_DT_ENDPOINT_SIZE,
 343         .bDescriptorType =      USB_DT_ENDPOINT,
 344
 345         .bEndpointAddress =     USB_DIR_IN,
 346         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 347         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 348         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS)
 349 };
 350
 351 static struct usb_ss_ep_comp_descriptor ss_ncm_notify_comp_desc = {
 352         .bLength =              sizeof(ss_ncm_notify_comp_desc),
 353         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 354
 355         /* the following 3 values can be tweaked if necessary */
 356         /* .bMaxBurst =         0, */
 357         /* .bmAttributes =      0, */
 358         .wBytesPerInterval =    cpu_to_le16(NCM_STATUS_BYTECOUNT),
 359 };
 360
 361 static struct usb_endpoint_descriptor ss_ncm_in_desc = {
 362         .bLength =              USB_DT_ENDPOINT_SIZE,
 363         .bDescriptorType =      USB_DT_ENDPOINT,
 364
 365         .bEndpointAddress =     USB_DIR_IN,
 366         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 367         .wMaxPacketSize =       cpu_to_le16(1024),
 368 };
 369
 370 static struct usb_endpoint_descriptor ss_ncm_out_desc = {
 371         .bLength =              USB_DT_ENDPOINT_SIZE,
 372         .bDescriptorType =      USB_DT_ENDPOINT,
 373
 374         .bEndpointAddress =     USB_DIR_OUT,
 375         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 376         .wMaxPacketSize =       cpu_to_le16(1024),
 377 };
 378
 379 static struct usb_ss_ep_comp_descriptor ss_ncm_bulk_comp_desc = {
 380         .bLength =              sizeof(ss_ncm_bulk_comp_desc),
 381         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 382
 383         /* the following 2 values can be tweaked if necessary */
 384         /* .bMaxBurst =         0, */
 385         /* .bmAttributes =      0, */
 386 };
 387
 388 static struct usb_descriptor_header *ncm_ss_function[] = {
 389         (struct usb_descriptor_header *) &ncm_iad_desc,
 390         /* CDC NCM control descriptors */
 391         (struct usb_descriptor_header *) &ncm_control_intf,
 392         (struct usb_descriptor_header *) &ncm_header_desc,
 393         (struct usb_descriptor_header *) &ncm_union_desc,
 394         (struct usb_descriptor_header *) &ecm_desc,
 395         (struct usb_descriptor_header *) &ncm_desc,
 396         (struct usb_descriptor_header *) &ss_ncm_notify_desc,
 397         (struct usb_descriptor_header *) &ss_ncm_notify_comp_desc,
 398         /* data interface, altsettings 0 and 1 */
 399         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 400         (struct usb_descriptor_header *) &ncm_data_intf,
 401         (struct usb_descriptor_header *) &ss_ncm_in_desc,
 402         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 403         (struct usb_descriptor_header *) &ss_ncm_out_desc,
 404         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 405         NULL,
 406 };
 407
 408 /* string descriptors: */
 409
 410 #define STRING_CTRL_IDX 0
 411 #define STRING_MAC_IDX  1
 412 #define STRING_DATA_IDX 2
 413 #define STRING_IAD_IDX  3
 414
 415 static struct usb_string ncm_string_defs[] = {
 416         [STRING_CTRL_IDX].s = "CDC Network Control Model (NCM)",
 417         [STRING_MAC_IDX].s = "",
 418         [STRING_DATA_IDX].s = "CDC Network Data",
 419         [STRING_IAD_IDX].s = "CDC NCM",
 420         {  } /* end of list */
 421 };
 422
 423 static struct usb_gadget_strings ncm_string_table = {
 424         .language =             0x0409, /* en-us */
 425         .strings =              ncm_string_defs,
 426 };
 427
 428 static struct usb_gadget_strings *ncm_strings[] = {
 429         &ncm_string_table,
 430         NULL,
 431 };
 432
 433 /*
 434  * Here are options for NCM Datagram Pointer table (NDP) parser.
 435  * There are 2 different formats: NDP16 and NDP32 in the spec (ch. 3),
 436  * in NDP16 offsets and sizes fields are 1 16bit word wide,
 437  * in NDP32 -- 2 16bit words wide. Also signatures are different.
 438  * To make the parser code the same, put the differences in the structure,
 439  * and switch pointers to the structures when the format is changed.
 440  */
 441
 442 struct ndp_parser_opts {
 443         u32             nth_sign;
 444         u32             ndp_sign;
 445         unsigned        nth_size;
 446         unsigned        ndp_size;
 447         unsigned        dpe_size;
 448         unsigned        ndplen_align;
 449         /* sizes in u16 units */
 450         unsigned        dgram_item_len; /* index or length */
 451         unsigned        block_length;
 452         unsigned        ndp_index;
 453         unsigned        reserved1;
 454         unsigned        reserved2;
 455         unsigned        next_ndp_index;
 456 };
 457
 458 #define INIT_NDP16_OPTS {                                       \
 459                 .nth_sign = USB_CDC_NCM_NTH16_SIGN,             \
 460                 .ndp_sign = USB_CDC_NCM_NDP16_NOCRC_SIGN,       \
 461                 .nth_size = sizeof(struct usb_cdc_ncm_nth16),   \
 462                 .ndp_size = sizeof(struct usb_cdc_ncm_ndp16),   \
 463                 .dpe_size = sizeof(struct usb_cdc_ncm_dpe16),   \
 464                 .ndplen_align = 4,                              \
 465                 .dgram_item_len = 1,                            \
 466                 .block_length = 1,                              \
 467                 .ndp_index = 1,                                 \
 468                 .reserved1 = 0,                                 \
 469                 .reserved2 = 0,                                 \
 470                 .next_ndp_index = 1,                            \
 471         }
 472
 473
 474 #define INIT_NDP32_OPTS {                                       \
 475                 .nth_sign = USB_CDC_NCM_NTH32_SIGN,             \
 476                 .ndp_sign = USB_CDC_NCM_NDP32_NOCRC_SIGN,       \
 477                 .nth_size = sizeof(struct usb_cdc_ncm_nth32),   \
 478                 .ndp_size = sizeof(struct usb_cdc_ncm_ndp32),   \
 479                 .dpe_size = sizeof(struct usb_cdc_ncm_dpe32),   \
 480                 .ndplen_align = 8,                              \
 481                 .dgram_item_len = 2,                            \
 482                 .block_length = 2,                              \
 483                 .ndp_index = 2,                                 \
 484                 .reserved1 = 1,                                 \
 485                 .reserved2 = 2,                                 \
 486                 .next_ndp_index = 2,                            \
 487         }
 488
 489 static const struct ndp_parser_opts ndp16_opts = INIT_NDP16_OPTS;
 490 static const struct ndp_parser_opts ndp32_opts = INIT_NDP32_OPTS;
 491
 492 static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
 493 {
 494         switch (size) {
 495         case 1:
 496                 put_unaligned_le16((u16)val, *p);
 497                 break;
 498         case 2:
 499                 put_unaligned_le32((u32)val, *p);
 500
 501                 break;
 502         default:
 503                 BUG();
 504         }
 505
 506         *p += size;
 507 }
 508
 509 static inline unsigned get_ncm(__le16 **p, unsigned size)
 510 {
 511         unsigned tmp;
 512
 513         switch (size) {
 514         case 1:
 515                 tmp = get_unaligned_le16(*p);
 516                 break;
 517         case 2:
 518                 tmp = get_unaligned_le32(*p);
 519                 break;
 520         default:
 521                 BUG();
 522         }
 523
 524         *p += size;
 525         return tmp;
 526 }
 527
 528 /*-------------------------------------------------------------------------*/
 529
 530 static inline void ncm_reset_values(struct f_ncm *ncm)
 531 {
 532         ncm->parser_opts = &ndp16_opts;
 533         ncm->is_crc = false;
 534         ncm->port.cdc_filter = DEFAULT_FILTER;
 535
 536         /* doesn't make sense for ncm, fixed size used */
 537         ncm->port.header_len = 0;
 538
 539         ncm->port.fixed_out_len = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
 540         ncm->port.fixed_in_len = NTB_DEFAULT_IN_SIZE;
 541 }
 542
 543 /*
 544  * Context: ncm->lock held
 545  */
 546 static void ncm_do_notify(struct f_ncm *ncm)
 547 {
 548         struct usb_request              *req = ncm->notify_req;
 549         struct usb_cdc_notification     *event;
 550         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 551         __le32                          *data;
 552         int                             status;
 553
 554         /* notification already in flight? */
 555         if (!req)
 556                 return;
 557
 558         event = req->buf;
 559         switch (ncm->notify_state) {
 560         case NCM_NOTIFY_NONE:
 561                 return;
 562
 563         case NCM_NOTIFY_CONNECT:
 564                 event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
 565                 if (ncm->is_open)
 566                         event->wValue = cpu_to_le16(1);
 567                 else
 568                         event->wValue = cpu_to_le16(0);
 569                 event->wLength = 0;
 570                 req->length = sizeof *event;
 571
 572                 DBG(cdev, "notify connect %s\n",
 573                                 ncm->is_open ? "true" : "false");
 574                 ncm->notify_state = NCM_NOTIFY_NONE;
 575                 break;
 576
 577         case NCM_NOTIFY_SPEED:
 578                 event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
 579                 event->wValue = cpu_to_le16(0);
 580                 event->wLength = cpu_to_le16(8);
 581                 req->length = NCM_STATUS_BYTECOUNT;
 582
 583                 /* SPEED_CHANGE data is up/down speeds in bits/sec */
 584                 data = req->buf + sizeof *event;
 585                 data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));
 586                 data[1] = data[0];
 587
 588                 DBG(cdev, "notify speed %d\n", ncm_bitrate(cdev->gadget));
 589                 ncm->notify_state = NCM_NOTIFY_CONNECT;
 590                 break;
 591         }
 592         event->bmRequestType = 0xA1;
 593         event->wIndex = cpu_to_le16(ncm->ctrl_id);
 594
 595         ncm->notify_req = NULL;
 596         /*
 597          * In double buffering if there is a space in FIFO,
 598          * completion callback can be called right after the call,
 599          * so unlocking
 600          */
 601         spin_unlock(&ncm->lock);
 602         status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC);
 603         spin_lock(&ncm->lock);
 604         if (status < 0) {
 605                 ncm->notify_req = req;
 606                 DBG(cdev, "notify --> %d\n", status);
 607         }
 608 }
 609
 610 /*
 611  * Context: ncm->lock held
 612  */
 613 static void ncm_notify(struct f_ncm *ncm)
 614 {
 615         /*
 616          * NOTE on most versions of Linux, host side cdc-ethernet
 617          * won't listen for notifications until its netdevice opens.
 618          * The first notification then sits in the FIFO for a long
 619          * time, and the second one is queued.
 620          *
 621          * If ncm_notify() is called before the second (CONNECT)
 622          * notification is sent, then it will reset to send the SPEED
 623          * notificaion again (and again, and again), but it's not a problem
 624          */
 625         ncm->notify_state = NCM_NOTIFY_SPEED;
 626         ncm_do_notify(ncm);
 627 }
 628
 629 static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req)
 630 {
 631         struct f_ncm                    *ncm = req->context;
 632         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 633         struct usb_cdc_notification     *event = req->buf;
 634
 635         spin_lock(&ncm->lock);
 636         switch (req->status) {
 637         case 0:
 638                 VDBG(cdev, "Notification %02x sent\n",
 639                      event->bNotificationType);
 640                 break;
 641         case -ECONNRESET:
 642         case -ESHUTDOWN:
 643                 ncm->notify_state = NCM_NOTIFY_NONE;
 644                 break;
 645         default:
 646                 DBG(cdev, "event %02x --> %d\n",
 647                         event->bNotificationType, req->status);
 648                 break;
 649         }
 650         ncm->notify_req = req;
 651         ncm_do_notify(ncm);
 652         spin_unlock(&ncm->lock);
 653 }
 654
 655 static void ncm_ep0out_complete(struct usb_ep *ep, struct usb_request *req)
 656 {
 657         /* now for SET_NTB_INPUT_SIZE only */
 658         unsigned                in_size;
 659         struct usb_function     *f = req->context;
 660         struct f_ncm            *ncm = func_to_ncm(f);
 661         struct usb_composite_dev *cdev = f->config->cdev;
 662
 663         req->context = NULL;
 664         if (req->status || req->actual != req->length) {
 665                 DBG(cdev, "Bad control-OUT transfer\n");
 666                 goto invalid;
 667         }
 668
 669         in_size = get_unaligned_le32(req->buf);
 670         if (in_size < USB_CDC_NCM_NTB_MIN_IN_SIZE ||
 671             in_size > le32_to_cpu(ntb_parameters.dwNtbInMaxSize)) {
 672                 DBG(cdev, "Got wrong INPUT SIZE (%d) from host\n", in_size);
 673                 goto invalid;
 674         }
 675
 676         ncm->port.fixed_in_len = in_size;
 677         VDBG(cdev, "Set NTB INPUT SIZE %d\n", in_size);
 678         return;
 679
 680 invalid:
 681         usb_ep_set_halt(ep);
 682         return;
 683 }
 684
 685 static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 686 {
 687         struct f_ncm            *ncm = func_to_ncm(f);
 688         struct usb_composite_dev *cdev = f->config->cdev;
 689         struct usb_request      *req = cdev->req;
 690         int                     value = -EOPNOTSUPP;
 691         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 692         u16                     w_value = le16_to_cpu(ctrl->wValue);
 693         u16                     w_length = le16_to_cpu(ctrl->wLength);
 694
 695         /*
 696          * composite driver infrastructure handles everything except
 697          * CDC class messages; interface activation uses set_alt().
 698          */
 699         switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 700         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 701                         | USB_CDC_SET_ETHERNET_PACKET_FILTER:
 702                 /*
 703                  * see 6.2.30: no data, wIndex = interface,
 704                  * wValue = packet filter bitmap
 705                  */
 706                 if (w_length != 0 || w_index != ncm->ctrl_id)
 707                         goto invalid;
 708                 DBG(cdev, "packet filter %02x\n", w_value);
 709                 /*
 710                  * REVISIT locking of cdc_filter.  This assumes the UDC
 711                  * driver won't have a concurrent packet TX irq running on
 712                  * another CPU; or that if it does, this write is atomic...
 713                  */
 714                 ncm->port.cdc_filter = w_value;
 715                 value = 0;
 716                 break;
 717         /*
 718          * and optionally:
 719          * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
 720          * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
 721          * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
 722          * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
 723          * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
 724          * case USB_CDC_GET_ETHERNET_STATISTIC:
 725          */
 726
 727         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 728                 | USB_CDC_GET_NTB_PARAMETERS:
 729
 730                 if (w_length == 0 || w_value != 0 || w_index != ncm->ctrl_id)
 731                         goto invalid;
 732                 value = w_length > sizeof ntb_parameters ?
 733                         sizeof ntb_parameters : w_length;
 734                 memcpy(req->buf, &ntb_parameters, value);
 735                 VDBG(cdev, "Host asked NTB parameters\n");
 736                 break;
 737
 738         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 739                 | USB_CDC_GET_NTB_INPUT_SIZE:
 740
 741                 if (w_length < 4 || w_value != 0 || w_index != ncm->ctrl_id)
 742                         goto invalid;
 743                 put_unaligned_le32(ncm->port.fixed_in_len, req->buf);
 744                 value = 4;
 745                 VDBG(cdev, "Host asked INPUT SIZE, sending %d\n",
 746                      ncm->port.fixed_in_len);
 747                 break;
 748
 749         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 750                 | USB_CDC_SET_NTB_INPUT_SIZE:
 751         {
 752                 if (w_length != 4 || w_value != 0 || w_index != ncm->ctrl_id)
 753                         goto invalid;
 754                 req->complete = ncm_ep0out_complete;
 755                 req->length = w_length;
 756                 req->context = f;
 757
 758                 value = req->length;
 759                 break;
 760         }
 761
 762         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 763                 | USB_CDC_GET_NTB_FORMAT:
 764         {
 765                 uint16_t format;
 766
 767                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 768                         goto invalid;
 769                 format = (ncm->parser_opts == &ndp16_opts) ? 0x0000 : 0x0001;
 770                 put_unaligned_le16(format, req->buf);
 771                 value = 2;
 772                 VDBG(cdev, "Host asked NTB FORMAT, sending %d\n", format);
 773                 break;
 774         }
 775
 776         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 777                 | USB_CDC_SET_NTB_FORMAT:
 778         {
 779                 if (w_length != 0 || w_index != ncm->ctrl_id)
 780                         goto invalid;
 781                 switch (w_value) {
 782                 case 0x0000:
 783                         ncm->parser_opts = &ndp16_opts;
 784                         DBG(cdev, "NCM16 selected\n");
 785                         break;
 786                 case 0x0001:
 787                         ncm->parser_opts = &ndp32_opts;
 788                         DBG(cdev, "NCM32 selected\n");
 789                         break;
 790                 default:
 791                         goto invalid;
 792                 }
 793                 value = 0;
 794                 break;
 795         }
 796         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 797                 | USB_CDC_GET_CRC_MODE:
 798         {
 799                 uint16_t is_crc;
 800
 801                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 802                         goto invalid;
 803                 is_crc = ncm->is_crc ? 0x0001 : 0x0000;
 804                 put_unaligned_le16(is_crc, req->buf);
 805                 value = 2;
 806                 VDBG(cdev, "Host asked CRC MODE, sending %d\n", is_crc);
 807                 break;
 808         }
 809
 810         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 811                 | USB_CDC_SET_CRC_MODE:
 812         {
 813                 int ndp_hdr_crc = 0;
 814
 815                 if (w_length != 0 || w_index != ncm->ctrl_id)
 816                         goto invalid;
 817                 switch (w_value) {
 818                 case 0x0000:
 819                         ncm->is_crc = false;
 820                         ndp_hdr_crc = NCM_NDP_HDR_NOCRC;
 821                         DBG(cdev, "non-CRC mode selected\n");
 822                         break;
 823                 case 0x0001:
 824                         ncm->is_crc = true;
 825                         ndp_hdr_crc = NCM_NDP_HDR_CRC;
 826                         DBG(cdev, "CRC mode selected\n");
 827                         break;
 828                 default:
 829                         goto invalid;
 830                 }
 831                 ncm->ndp_sign = ncm->parser_opts->ndp_sign | ndp_hdr_crc;
 832                 value = 0;
 833                 break;
 834         }
 835
 836         /* and disabled in ncm descriptor: */
 837         /* case USB_CDC_GET_NET_ADDRESS: */
 838         /* case USB_CDC_SET_NET_ADDRESS: */
 839         /* case USB_CDC_GET_MAX_DATAGRAM_SIZE: */
 840         /* case USB_CDC_SET_MAX_DATAGRAM_SIZE: */
 841
 842         default:
 843 invalid:
 844                 DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 845                         ctrl->bRequestType, ctrl->bRequest,
 846                         w_value, w_index, w_length);
 847         }
 848
 849         /* respond with data transfer or status phase? */
 850         if (value >= 0) {
 851                 DBG(cdev, "ncm req%02x.%02x v%04x i%04x l%d\n",
 852                         ctrl->bRequestType, ctrl->bRequest,
 853                         w_value, w_index, w_length);
 854                 req->zero = 0;
 855                 req->length = value;
 856                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 857                 if (value < 0)
 858                         ERROR(cdev, "ncm req %02x.%02x response err %d\n",
 859                                         ctrl->bRequestType, ctrl->bRequest,
 860                                         value);
 861         }
 862
 863         /* device either stalls (value < 0) or reports success */
 864         return value;
 865 }
 866
 867
 868 static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 869 {
 870         struct f_ncm            *ncm = func_to_ncm(f);
 871         struct usb_composite_dev *cdev = f->config->cdev;
 872
 873         /* Control interface has only altsetting 0 */
 874         if (intf == ncm->ctrl_id) {
 875                 if (alt != 0)
 876                         goto fail;
 877
 878                 DBG(cdev, "reset ncm control %d\n", intf);
 879                 usb_ep_disable(ncm->notify);
 880
 881                 if (!(ncm->notify->desc)) {
 882                         DBG(cdev, "init ncm ctrl %d\n", intf);
 883                         if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
 884                                 goto fail;
 885                 }
 886                 usb_ep_enable(ncm->notify);
 887
 888         /* Data interface has two altsettings, 0 and 1 */
 889         } else if (intf == ncm->data_id) {
 890                 if (alt > 1)
 891                         goto fail;
 892
 893                 if (ncm->port.in_ep->enabled) {
 894                         DBG(cdev, "reset ncm\n");
 895                         ncm->timer_stopping = true;
 896                         ncm->netdev = NULL;
 897                         gether_disconnect(&ncm->port);
 898                         ncm_reset_values(ncm);
 899                 }
 900
 901                 /*
 902                  * CDC Network only sends data in non-default altsettings.
 903                  * Changing altsettings resets filters, statistics, etc.
 904                  */
 905                 if (alt == 1) {
 906                         struct net_device       *net;
 907
 908                         if (!ncm->port.in_ep->desc ||
 909                             !ncm->port.out_ep->desc) {
 910                                 DBG(cdev, "init ncm\n");
 911                                 if (config_ep_by_speed(cdev->gadget, f,
 912                                                        ncm->port.in_ep) ||
 913                                     config_ep_by_speed(cdev->gadget, f,
 914                                                        ncm->port.out_ep)) {
 915                                         ncm->port.in_ep->desc = NULL;
 916                                         ncm->port.out_ep->desc = NULL;
 917                                         goto fail;
 918                                 }
 919                         }
 920
 921                         /* TODO */
 922                         /* Enable zlps by default for NCM conformance;
 923                          * override for musb_hdrc (avoids txdma ovhead)
 924                          */
 925                         ncm->port.is_zlp_ok =
 926                                 gadget_is_zlp_supported(cdev->gadget);
 927                         ncm->port.no_skb_reserve =
 928                                 gadget_avoids_skb_reserve(cdev->gadget);
 929                         ncm->port.cdc_filter = DEFAULT_FILTER;
 930                         DBG(cdev, "activate ncm\n");
 931                         net = gether_connect(&ncm->port);
 932                         if (IS_ERR(net))
 933                                 return PTR_ERR(net);
 934                         ncm->netdev = net;
 935                         ncm->timer_stopping = false;
 936                 }
 937
 938                 spin_lock(&ncm->lock);
 939                 ncm_notify(ncm);
 940                 spin_unlock(&ncm->lock);
 941         } else
 942                 goto fail;
 943
 944         return 0;
 945 fail:
 946         return -EINVAL;
 947 }
 948
 949 /*
 950  * Because the data interface supports multiple altsettings,
 951  * this NCM function *MUST* implement a get_alt() method.
 952  */
 953 static int ncm_get_alt(struct usb_function *f, unsigned intf)
 954 {
 955         struct f_ncm            *ncm = func_to_ncm(f);
 956
 957         if (intf == ncm->ctrl_id)
 958                 return 0;
 959         return ncm->port.in_ep->enabled ? 1 : 0;
 960 }
 961
 962 static struct sk_buff *package_for_tx(struct f_ncm *ncm)
 963 {
 964         __le16          *ntb_iter;
 965         struct sk_buff  *skb2 = NULL;
 966         unsigned        ndp_pad;
 967         unsigned        ndp_index;
 968         unsigned        new_len;
 969
 970         const struct ndp_parser_opts *opts = ncm->parser_opts;
 971         const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
 972         const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
 973
 974         /* Stop the timer */
 975         hrtimer_try_to_cancel(&ncm->task_timer);
 976
 977         ndp_pad = ALIGN(ncm->skb_tx_data->len, ndp_align) -
 978                         ncm->skb_tx_data->len;
 979         ndp_index = ncm->skb_tx_data->len + ndp_pad;
 980         new_len = ndp_index + dgram_idx_len + ncm->skb_tx_ndp->len;
 981
 982         /* Set the final BlockLength and wNdpIndex */
 983         ntb_iter = (void *) ncm->skb_tx_data->data;
 984         /* Increment pointer to BlockLength */
 985         ntb_iter += 2 + 1 + 1;
 986         put_ncm(&ntb_iter, opts->block_length, new_len);
 987         put_ncm(&ntb_iter, opts->ndp_index, ndp_index);
 988
 989         /* Set the final NDP wLength */
 990         new_len = opts->ndp_size +
 991                         (ncm->ndp_dgram_count * dgram_idx_len);
 992         ncm->ndp_dgram_count = 0;
 993         /* Increment from start to wLength */
 994         ntb_iter = (void *) ncm->skb_tx_ndp->data;
 995         ntb_iter += 2;
 996         put_unaligned_le16(new_len, ntb_iter);
 997
 998         /* Merge the skbs */
 999         swap(skb2, ncm->skb_tx_data);
1000         if (ncm->skb_tx_data) {
1001                 dev_kfree_skb_any(ncm->skb_tx_data);
1002                 ncm->skb_tx_data = NULL;
1003         }
1004
1005         /* Insert NDP alignment. */
1006         ntb_iter = (void *) skb_put(skb2, ndp_pad);
1007         memset(ntb_iter, 0, ndp_pad);
1008
1009         /* Copy NTB across. */
1010         ntb_iter = (void *) skb_put(skb2, ncm->skb_tx_ndp->len);
1011         memcpy(ntb_iter, ncm->skb_tx_ndp->data, ncm->skb_tx_ndp->len);
1012         dev_kfree_skb_any(ncm->skb_tx_ndp);
1013         ncm->skb_tx_ndp = NULL;
1014
1015         /* Insert zero'd datagram. */
1016         ntb_iter = (void *) skb_put(skb2, dgram_idx_len);
1017         memset(ntb_iter, 0, dgram_idx_len);
1018
1019         return skb2;
1020 }
1021
1022 static struct sk_buff *ncm_wrap_ntb(struct gether *port,
1023                                     struct sk_buff *skb)
1024 {
1025         struct f_ncm    *ncm = func_to_ncm(&port->func);
1026         struct sk_buff  *skb2 = NULL;
1027         int             ncb_len = 0;
1028         __le16          *ntb_data;
1029         __le16          *ntb_ndp;
1030         int             dgram_pad;
1031
1032         unsigned        max_size = ncm->port.fixed_in_len;
1033         const struct ndp_parser_opts *opts = ncm->parser_opts;
1034         const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
1035         const int div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
1036         const int rem = le16_to_cpu(ntb_parameters.wNdpInPayloadRemainder);
1037         const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
1038
1039         if (!skb && !ncm->skb_tx_data)
1040                 return NULL;
1041
1042         if (skb) {
1043                 /* Add the CRC if required up front */
1044                 if (ncm->is_crc) {
1045                         uint32_t        crc;
1046                         __le16          *crc_pos;
1047
1048                         crc = ~crc32_le(~0,
1049                                         skb->data,
1050                                         skb->len);
1051                         crc_pos = (void *) skb_put(skb, sizeof(uint32_t));
1052                         put_unaligned_le32(crc, crc_pos);
1053                 }
1054
1055                 /* If the new skb is too big for the current NCM NTB then
1056                  * set the current stored skb to be sent now and clear it
1057                  * ready for new data.
1058                  * NOTE: Assume maximum align for speed of calculation.
1059                  */
1060                 if (ncm->skb_tx_data
1061                     && (ncm->ndp_dgram_count >= TX_MAX_NUM_DPE
1062                     || (ncm->skb_tx_data->len +
1063                     div + rem + skb->len +
1064                     ncm->skb_tx_ndp->len + ndp_align + (2 * dgram_idx_len))
1065                     > max_size)) {
1066                         skb2 = package_for_tx(ncm);
1067                         if (!skb2)
1068                                 goto err;
1069                 }
1070
1071                 if (!ncm->skb_tx_data) {
1072                         ncb_len = opts->nth_size;
1073                         dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1074                         ncb_len += dgram_pad;
1075
1076                         /* Create a new skb for the NTH and datagrams. */
1077                         ncm->skb_tx_data = alloc_skb(max_size, GFP_ATOMIC);
1078                         if (!ncm->skb_tx_data)
1079                                 goto err;
1080
1081                         ntb_data = (void *) skb_put(ncm->skb_tx_data, ncb_len);
1082                         memset(ntb_data, 0, ncb_len);
1083                         /* dwSignature */
1084                         put_unaligned_le32(opts->nth_sign, ntb_data);
1085                         ntb_data += 2;
1086                         /* wHeaderLength */
1087                         put_unaligned_le16(opts->nth_size, ntb_data++);
1088
1089                         /* Allocate an skb for storing the NDP,
1090                          * TX_MAX_NUM_DPE should easily suffice for a
1091                          * 16k packet.
1092                          */
1093                         ncm->skb_tx_ndp = alloc_skb((int)(opts->ndp_size
1094                                                     + opts->dpe_size
1095                                                     * TX_MAX_NUM_DPE),
1096                                                     GFP_ATOMIC);
1097                         if (!ncm->skb_tx_ndp)
1098                                 goto err;
1099                         ntb_ndp = (void *) skb_put(ncm->skb_tx_ndp,
1100                                                     opts->ndp_size);
1101                         memset(ntb_ndp, 0, ncb_len);
1102                         /* dwSignature */
1103                         put_unaligned_le32(ncm->ndp_sign, ntb_ndp);
1104                         ntb_ndp += 2;
1105
1106                         /* There is always a zeroed entry */
1107                         ncm->ndp_dgram_count = 1;
1108
1109                         /* Note: we skip opts->next_ndp_index */
1110                 }
1111
1112                 /* Delay the timer. */
1113                 hrtimer_start(&ncm->task_timer,
1114                               ktime_set(0, TX_TIMEOUT_NSECS),
1115                               HRTIMER_MODE_REL);
1116
1117                 /* Add the datagram position entries */
1118                 ntb_ndp = (void *) skb_put(ncm->skb_tx_ndp, dgram_idx_len);
1119                 memset(ntb_ndp, 0, dgram_idx_len);
1120
1121                 ncb_len = ncm->skb_tx_data->len;
1122                 dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1123                 ncb_len += dgram_pad;
1124
1125                 /* (d)wDatagramIndex */
1126                 put_ncm(&ntb_ndp, opts->dgram_item_len, ncb_len);
1127                 /* (d)wDatagramLength */
1128                 put_ncm(&ntb_ndp, opts->dgram_item_len, skb->len);
1129                 ncm->ndp_dgram_count++;
1130
1131                 /* Add the new data to the skb */
1132                 ntb_data = (void *) skb_put(ncm->skb_tx_data, dgram_pad);
1133                 memset(ntb_data, 0, dgram_pad);
1134                 ntb_data = (void *) skb_put(ncm->skb_tx_data, skb->len);
1135                 memcpy(ntb_data, skb->data, skb->len);
1136                 dev_kfree_skb_any(skb);
1137                 skb = NULL;
1138
1139         } else if (ncm->skb_tx_data && ncm->timer_force_tx) {
1140                 /* If the tx was requested because of a timeout then send */
1141                 skb2 = package_for_tx(ncm);
1142                 if (!skb2)
1143                         goto err;
1144         }
1145
1146         return skb2;
1147
1148 err:
1149         ncm->netdev->stats.tx_dropped++;
1150
1151         if (skb)
1152                 dev_kfree_skb_any(skb);
1153         if (ncm->skb_tx_data)
1154                 dev_kfree_skb_any(ncm->skb_tx_data);
1155         if (ncm->skb_tx_ndp)
1156                 dev_kfree_skb_any(ncm->skb_tx_ndp);
1157
1158         return NULL;
1159 }
1160
1161 /*
1162  * This transmits the NTB if there are frames waiting.
1163  */
1164 static void ncm_tx_tasklet(unsigned long data)
1165 {
1166         struct f_ncm    *ncm = (void *)data;
1167
1168         if (ncm->timer_stopping)
1169                 return;
1170
1171         /* Only send if data is available. */
1172         if (ncm->skb_tx_data) {
1173                 ncm->timer_force_tx = true;
1174
1175                 /* XXX This allowance of a NULL skb argument to ndo_start_xmit
1176                  * XXX is not sane.  The gadget layer should be redesigned so
1177                  * XXX that the dev->wrap() invocations to build SKBs is transparent
1178                  * XXX and performed in some way outside of the ndo_start_xmit
1179                  * XXX interface.
1180                  */
1181                 ncm->netdev->netdev_ops->ndo_start_xmit(NULL, ncm->netdev);
1182
1183                 ncm->timer_force_tx = false;
1184         }
1185 }
1186
1187 /*
1188  * The transmit should only be run if no skb data has been sent
1189  * for a certain duration.
1190  */
1191 static enum hrtimer_restart ncm_tx_timeout(struct hrtimer *data)
1192 {
1193         struct f_ncm *ncm = container_of(data, struct f_ncm, task_timer);
1194         tasklet_schedule(&ncm->tx_tasklet);
1195         return HRTIMER_NORESTART;
1196 }
1197
1198 static int ncm_unwrap_ntb(struct gether *port,
1199                           struct sk_buff *skb,
1200                           struct sk_buff_head *list)
1201 {
1202         struct f_ncm    *ncm = func_to_ncm(&port->func);
1203         __le16          *tmp = (void *) skb->data;
1204         unsigned        index, index2;
1205         int             ndp_index;
1206         unsigned        dg_len, dg_len2;
1207         unsigned        ndp_len;
1208         struct sk_buff  *skb2;
1209         int             ret = -EINVAL;
1210         unsigned        max_size = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
1211         const struct ndp_parser_opts *opts = ncm->parser_opts;
1212         unsigned        crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
1213         int             dgram_counter;
1214
1215         /* dwSignature */
1216         if (get_unaligned_le32(tmp) != opts->nth_sign) {
1217                 INFO(port->func.config->cdev, "Wrong NTH SIGN, skblen %d\n",
1218                         skb->len);
1219                 print_hex_dump(KERN_INFO, "HEAD:", DUMP_PREFIX_ADDRESS, 32, 1,
1220                                skb->data, 32, false);
1221
1222                 goto err;
1223         }
1224         tmp += 2;
1225         /* wHeaderLength */
1226         if (get_unaligned_le16(tmp++) != opts->nth_size) {
1227                 INFO(port->func.config->cdev, "Wrong NTB headersize\n");
1228                 goto err;
1229         }
1230         tmp++; /* skip wSequence */
1231
1232         /* (d)wBlockLength */
1233         if (get_ncm(&tmp, opts->block_length) > max_size) {
1234                 INFO(port->func.config->cdev, "OUT size exceeded\n");
1235                 goto err;
1236         }
1237
1238         ndp_index = get_ncm(&tmp, opts->ndp_index);
1239
1240         /* Run through all the NDP's in the NTB */
1241         do {
1242                 /* NCM 3.2 */
1243                 if (((ndp_index % 4) != 0) &&
1244                                 (ndp_index < opts->nth_size)) {
1245                         INFO(port->func.config->cdev, "Bad index: %#X\n",
1246                              ndp_index);
1247                         goto err;
1248                 }
1249
1250                 /* walk through NDP */
1251                 tmp = (void *)(skb->data + ndp_index);
1252                 if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
1253                         INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
1254                         goto err;
1255                 }
1256                 tmp += 2;
1257
1258                 ndp_len = get_unaligned_le16(tmp++);
1259                 /*
1260                  * NCM 3.3.1
1261                  * entry is 2 items
1262                  * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
1263                  * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
1264                  * Each entry is a dgram index and a dgram length.
1265                  */
1266                 if ((ndp_len < opts->ndp_size
1267                                 + 2 * 2 * (opts->dgram_item_len * 2))
1268                                 || (ndp_len % opts->ndplen_align != 0)) {
1269                         INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
1270                              ndp_len);
1271                         goto err;
1272                 }
1273                 tmp += opts->reserved1;
1274                 /* Check for another NDP (d)wNextNdpIndex */
1275                 ndp_index = get_ncm(&tmp, opts->next_ndp_index);
1276                 tmp += opts->reserved2;
1277
1278                 ndp_len -= opts->ndp_size;
1279                 index2 = get_ncm(&tmp, opts->dgram_item_len);
1280                 dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1281                 dgram_counter = 0;
1282
1283                 do {
1284                         index = index2;
1285                         dg_len = dg_len2;
1286                         if (dg_len < 14 + crc_len) { /* ethernet hdr + crc */
1287                                 INFO(port->func.config->cdev,
1288                                      "Bad dgram length: %#X\n", dg_len);
1289                                 goto err;
1290                         }
1291                         if (ncm->is_crc) {
1292                                 uint32_t crc, crc2;
1293
1294                                 crc = get_unaligned_le32(skb->data +
1295                                                          index + dg_len -
1296                                                          crc_len);
1297                                 crc2 = ~crc32_le(~0,
1298                                                  skb->data + index,
1299                                                  dg_len - crc_len);
1300                                 if (crc != crc2) {
1301                                         INFO(port->func.config->cdev,
1302                                              "Bad CRC\n");
1303                                         goto err;
1304                                 }
1305                         }
1306
1307                         index2 = get_ncm(&tmp, opts->dgram_item_len);
1308                         dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1309
1310                         /*
1311                          * Copy the data into a new skb.
1312                          * This ensures the truesize is correct
1313                          */
1314                         skb2 = netdev_alloc_skb_ip_align(ncm->netdev,
1315                                                          dg_len - crc_len);
1316                         if (skb2 == NULL)
1317                                 goto err;
1318                         memcpy(skb_put(skb2, dg_len - crc_len),
1319                                skb->data + index, dg_len - crc_len);
1320
1321                         skb_queue_tail(list, skb2);
1322
1323                         ndp_len -= 2 * (opts->dgram_item_len * 2);
1324
1325                         dgram_counter++;
1326
1327                         if (index2 == 0 || dg_len2 == 0)
1328                                 break;
1329                 } while (ndp_len > 2 * (opts->dgram_item_len * 2));
1330         } while (ndp_index);
1331
1332         dev_kfree_skb_any(skb);
1333
1334         VDBG(port->func.config->cdev,
1335              "Parsed NTB with %d frames\n", dgram_counter);
1336         return 0;
1337 err:
1338         skb_queue_purge(list);
1339         dev_kfree_skb_any(skb);
1340         return ret;
1341 }
1342
1343 static void ncm_disable(struct usb_function *f)
1344 {
1345         struct f_ncm            *ncm = func_to_ncm(f);
1346         struct usb_composite_dev *cdev = f->config->cdev;
1347
1348         DBG(cdev, "ncm deactivated\n");
1349
1350         if (ncm->port.in_ep->enabled) {
1351                 ncm->timer_stopping = true;
1352                 ncm->netdev = NULL;
1353                 gether_disconnect(&ncm->port);
1354         }
1355
1356         if (ncm->notify->enabled) {
1357                 usb_ep_disable(ncm->notify);
1358                 ncm->notify->desc = NULL;
1359         }
1360 }
1361
1362 /*-------------------------------------------------------------------------*/
1363
1364 /*
1365  * Callbacks let us notify the host about connect/disconnect when the
1366  * net device is opened or closed.
1367  *
1368  * For testing, note that link states on this side include both opened
1369  * and closed variants of:
1370  *
1371  *   - disconnected/unconfigured
1372  *   - configured but inactive (data alt 0)
1373  *   - configured and active (data alt 1)
1374  *
1375  * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
1376  * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
1377  * imply the host is actually polling the notification endpoint, and
1378  * likewise that "active" doesn't imply it's actually using the data
1379  * endpoints for traffic.
1380  */
1381
1382 static void ncm_open(struct gether *geth)
1383 {
1384         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1385
1386         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1387
1388         spin_lock(&ncm->lock);
1389         ncm->is_open = true;
1390         ncm_notify(ncm);
1391         spin_unlock(&ncm->lock);
1392 }
1393
1394 static void ncm_close(struct gether *geth)
1395 {
1396         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1397
1398         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1399
1400         spin_lock(&ncm->lock);
1401         ncm->is_open = false;
1402         ncm_notify(ncm);
1403         spin_unlock(&ncm->lock);
1404 }
1405
1406 /*-------------------------------------------------------------------------*/
1407
1408 /* ethernet function driver setup/binding */
1409
1410 static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
1411 {
1412         struct usb_composite_dev *cdev = c->cdev;
1413         struct f_ncm            *ncm = func_to_ncm(f);
1414         struct usb_string       *us;
1415         int                     status;
1416         struct usb_ep           *ep;
1417         struct f_ncm_opts       *ncm_opts;
1418
1419         if (!can_support_ecm(cdev->gadget))
1420                 return -EINVAL;
1421
1422         ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1423         /*
1424          * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
1425          * configurations are bound in sequence with list_for_each_entry,
1426          * in each configuration its functions are bound in sequence
1427          * with list_for_each_entry, so we assume no race condition
1428          * with regard to ncm_opts->bound access
1429          */
1430         if (!ncm_opts->bound) {
1431                 mutex_lock(&ncm_opts->lock);
1432                 gether_set_gadget(ncm_opts->net, cdev->gadget);
1433                 status = gether_register_netdev(ncm_opts->net);
1434                 mutex_unlock(&ncm_opts->lock);
1435                 if (status)
1436                         return status;
1437                 ncm_opts->bound = true;
1438         }
1439         us = usb_gstrings_attach(cdev, ncm_strings,
1440                                  ARRAY_SIZE(ncm_string_defs));
1441         if (IS_ERR(us))
1442                 return PTR_ERR(us);
1443         ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
1444         ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
1445         ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
1446         ecm_desc.iMACAddress = us[STRING_MAC_IDX].id;
1447         ncm_iad_desc.iFunction = us[STRING_IAD_IDX].id;
1448
1449         /* allocate instance-specific interface IDs */
1450         status = usb_interface_id(c, f);
1451         if (status < 0)
1452                 goto fail;
1453         ncm->ctrl_id = status;
1454         ncm_iad_desc.bFirstInterface = status;
1455
1456         ncm_control_intf.bInterfaceNumber = status;
1457         ncm_union_desc.bMasterInterface0 = status;
1458
1459         status = usb_interface_id(c, f);
1460         if (status < 0)
1461                 goto fail;
1462         ncm->data_id = status;
1463
1464         ncm_data_nop_intf.bInterfaceNumber = status;
1465         ncm_data_intf.bInterfaceNumber = status;
1466         ncm_union_desc.bSlaveInterface0 = status;
1467
1468         status = -ENODEV;
1469
1470         /* allocate instance-specific endpoints */
1471         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
1472         if (!ep)
1473                 goto fail;
1474         ncm->port.in_ep = ep;
1475
1476         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
1477         if (!ep)
1478                 goto fail;
1479         ncm->port.out_ep = ep;
1480
1481         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
1482         if (!ep)
1483                 goto fail;
1484         ncm->notify = ep;
1485
1486         status = -ENOMEM;
1487
1488         /* allocate notification request and buffer */
1489         ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
1490         if (!ncm->notify_req)
1491                 goto fail;
1492         ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
1493         if (!ncm->notify_req->buf)
1494                 goto fail;
1495         ncm->notify_req->context = ncm;
1496         ncm->notify_req->complete = ncm_notify_complete;
1497
1498         /*
1499          * support all relevant hardware speeds... we expect that when
1500          * hardware is dual speed, all bulk-capable endpoints work at
1501          * both speeds
1502          */
1503         hs_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1504         hs_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1505         hs_ncm_notify_desc.bEndpointAddress =
1506                 fs_ncm_notify_desc.bEndpointAddress;
1507
1508         ss_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1509         ss_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1510         ss_ncm_notify_desc.bEndpointAddress =
1511                 fs_ncm_notify_desc.bEndpointAddress;
1512
1513         status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
1514                         ncm_ss_function, NULL);
1515         if (status)
1516                 goto fail;
1517
1518         /*
1519          * NOTE:  all that is done without knowing or caring about
1520          * the network link ... which is unavailable to this code
1521          * until we're activated via set_alt().
1522          */
1523
1524         ncm->port.open = ncm_open;
1525         ncm->port.close = ncm_close;
1526
1527         tasklet_init(&ncm->tx_tasklet, ncm_tx_tasklet, (unsigned long) ncm);
1528         hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1529         ncm->task_timer.function = ncm_tx_timeout;
1530
1531         DBG(cdev, "CDC Network: %s speed IN/%s OUT/%s NOTIFY/%s\n",
1532                         gadget_is_superspeed(c->cdev->gadget) ? "super" :
1533                         gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
1534                         ncm->port.in_ep->name, ncm->port.out_ep->name,
1535                         ncm->notify->name);
1536         return 0;
1537
1538 fail:
1539         if (ncm->notify_req) {
1540                 kfree(ncm->notify_req->buf);
1541                 usb_ep_free_request(ncm->notify, ncm->notify_req);
1542         }
1543
1544         ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1545
1546         return status;
1547 }
1548
1549 static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
1550 {
1551         return container_of(to_config_group(item), struct f_ncm_opts,
1552                             func_inst.group);
1553 }
1554
1555 /* f_ncm_item_ops */
1556 USB_ETHERNET_CONFIGFS_ITEM(ncm);
1557
1558 /* f_ncm_opts_dev_addr */
1559 USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
1560
1561 /* f_ncm_opts_host_addr */
1562 USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
1563
1564 /* f_ncm_opts_qmult */
1565 USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
1566
1567 /* f_ncm_opts_ifname */
1568 USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
1569
1570 static struct configfs_attribute *ncm_attrs[] = {
1571         &ncm_opts_attr_dev_addr,
1572         &ncm_opts_attr_host_addr,
1573         &ncm_opts_attr_qmult,
1574         &ncm_opts_attr_ifname,
1575         NULL,
1576 };
1577
1578 static struct config_item_type ncm_func_type = {
1579         .ct_item_ops    = &ncm_item_ops,
1580         .ct_attrs       = ncm_attrs,
1581         .ct_owner       = THIS_MODULE,
1582 };
1583
1584 static void ncm_free_inst(struct usb_function_instance *f)
1585 {
1586         struct f_ncm_opts *opts;
1587
1588         opts = container_of(f, struct f_ncm_opts, func_inst);
1589         if (opts->bound)
1590                 gether_cleanup(netdev_priv(opts->net));
1591         else
1592                 free_netdev(opts->net);
1593         kfree(opts);
1594 }
1595
1596 static struct usb_function_instance *ncm_alloc_inst(void)
1597 {
1598         struct f_ncm_opts *opts;
1599
1600         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1601         if (!opts)
1602                 return ERR_PTR(-ENOMEM);
1603         mutex_init(&opts->lock);
1604         opts->func_inst.free_func_inst = ncm_free_inst;
1605         opts->net = gether_setup_default();
1606         if (IS_ERR(opts->net)) {
1607                 struct net_device *net = opts->net;
1608                 kfree(opts);
1609                 return ERR_CAST(net);
1610         }
1611
1612         config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type);
1613
1614         return &opts->func_inst;
1615 }
1616
1617 static void ncm_free(struct usb_function *f)
1618 {
1619         struct f_ncm *ncm;
1620         struct f_ncm_opts *opts;
1621
1622         ncm = func_to_ncm(f);
1623         opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1624         kfree(ncm);
1625         mutex_lock(&opts->lock);
1626         opts->refcnt--;
1627         mutex_unlock(&opts->lock);
1628 }
1629
1630 static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
1631 {
1632         struct f_ncm *ncm = func_to_ncm(f);
1633
1634         DBG(c->cdev, "ncm unbind\n");
1635
1636         hrtimer_cancel(&ncm->task_timer);
1637         tasklet_kill(&ncm->tx_tasklet);
1638
1639         ncm_string_defs[0].id = 0;
1640         usb_free_all_descriptors(f);
1641
1642         kfree(ncm->notify_req->buf);
1643         usb_ep_free_request(ncm->notify, ncm->notify_req);
1644 }
1645
1646 static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
1647 {
1648         struct f_ncm            *ncm;
1649         struct f_ncm_opts       *opts;
1650         int status;
1651
1652         /* allocate and initialize one new instance */
1653         ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);
1654         if (!ncm)
1655                 return ERR_PTR(-ENOMEM);
1656
1657         opts = container_of(fi, struct f_ncm_opts, func_inst);
1658         mutex_lock(&opts->lock);
1659         opts->refcnt++;
1660
1661         /* export host's Ethernet address in CDC format */
1662         status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
1663                                       sizeof(ncm->ethaddr));
1664         if (status < 12) { /* strlen("01234567890a") */
1665                 kfree(ncm);
1666                 mutex_unlock(&opts->lock);
1667                 return ERR_PTR(-EINVAL);
1668         }
1669         ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
1670
1671         spin_lock_init(&ncm->lock);
1672         ncm_reset_values(ncm);
1673         ncm->port.ioport = netdev_priv(opts->net);
1674         mutex_unlock(&opts->lock);
1675         ncm->port.is_fixed = true;
1676         ncm->port.supports_multi_frame = true;
1677
1678         ncm->port.func.name = "cdc_network";
1679         /* descriptors are per-instance copies */
1680         ncm->port.func.bind = ncm_bind;
1681         ncm->port.func.unbind = ncm_unbind;
1682         ncm->port.func.set_alt = ncm_set_alt;
1683         ncm->port.func.get_alt = ncm_get_alt;
1684         ncm->port.func.setup = ncm_setup;
1685         ncm->port.func.disable = ncm_disable;
1686         ncm->port.func.free_func = ncm_free;
1687
1688         ncm->port.wrap = ncm_wrap_ntb;
1689         ncm->port.unwrap = ncm_unwrap_ntb;
1690
1691         return &ncm->port.func;
1692 }
1693
1694 DECLARE_USB_FUNCTION_INIT(ncm, ncm_alloc_inst, ncm_alloc);
1695 MODULE_LICENSE("GPL");
1696 MODULE_AUTHOR("Yauheni Kaliuta");