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/interrupt.h>
  20 #include <linux/module.h>
  21 #include <linux/device.h>
  22 #include <linux/etherdevice.h>
  23 #include <linux/crc32.h>
  24
  25 #include <linux/usb/cdc.h>
  26
  27 #include "u_ether.h"
  28 #include "u_ether_configfs.h"
  29 #include "u_ncm.h"
  30
  31 /*
  32  * This function is a "CDC Network Control Model" (CDC NCM) Ethernet link.
  33  * NCM is intended to be used with high-speed network attachments.
  34  *
  35  * Note that NCM requires the use of "alternate settings" for its data
  36  * interface.  This means that the set_alt() method has real work to do,
  37  * and also means that a get_alt() method is required.
  38  */
  39
  40 /* to trigger crc/non-crc ndp signature */
  41
  42 #define NCM_NDP_HDR_CRC_MASK    0x01000000
  43 #define NCM_NDP_HDR_CRC         0x01000000
  44 #define NCM_NDP_HDR_NOCRC       0x00000000
  45
  46 enum ncm_notify_state {
  47         NCM_NOTIFY_NONE,                /* don't notify */
  48         NCM_NOTIFY_CONNECT,             /* issue CONNECT next */
  49         NCM_NOTIFY_SPEED,               /* issue SPEED_CHANGE next */
  50 };
  51
  52 struct f_ncm {
  53         struct gether                   port;
  54         u8                              ctrl_id, data_id;
  55
  56         char                            ethaddr[14];
  57
  58         struct usb_ep                   *notify;
  59         struct usb_request              *notify_req;
  60         u8                              notify_state;
  61         atomic_t                        notify_count;
  62         bool                            is_open;
  63
  64         const struct ndp_parser_opts    *parser_opts;
  65         bool                            is_crc;
  66         u32                             ndp_sign;
  67
  68         /*
  69          * for notification, it is accessed from both
  70          * callback and ethernet open/close
  71          */
  72         spinlock_t                      lock;
  73
  74         struct net_device               *netdev;
  75
  76         /* For multi-frame NDP TX */
  77         struct sk_buff                  *skb_tx_data;
  78         struct sk_buff                  *skb_tx_ndp;
  79         u16                             ndp_dgram_count;
  80         bool                            timer_force_tx;
  81         struct tasklet_struct           tx_tasklet;
  82         struct hrtimer                  task_timer;
  83
  84         bool                            timer_stopping;
  85 };
  86
  87 static inline struct f_ncm *func_to_ncm(struct usb_function *f)
  88 {
  89         return container_of(f, struct f_ncm, port.func);
  90 }
  91
  92 /* peak (theoretical) bulk transfer rate in bits-per-second */
  93 static inline unsigned ncm_bitrate(struct usb_gadget *g)
  94 {
  95         if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
  96                 return 4250000000U;
  97         else if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
  98                 return 3750000000U;
  99         else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
 100                 return 13 * 512 * 8 * 1000 * 8;
 101         else
 102                 return 19 *  64 * 1 * 1000 * 8;
 103 }
 104
 105 /*-------------------------------------------------------------------------*/
 106
 107 /*
 108  * We cannot group frames so use just the minimal size which ok to put
 109  * one max-size ethernet frame.
 110  * If the host can group frames, allow it to do that, 16K is selected,
 111  * because it's used by default by the current linux host driver
 112  */
 113 #define NTB_DEFAULT_IN_SIZE     16384
 114 #define NTB_OUT_SIZE            16384
 115
 116 /* Allocation for storing the NDP, 32 should suffice for a
 117  * 16k packet. This allows a maximum of 32 * 507 Byte packets to
 118  * be transmitted in a single 16kB skb, though when sending full size
 119  * packets this limit will be plenty.
 120  * Smaller packets are not likely to be trying to maximize the
 121  * throughput and will be mstly sending smaller infrequent frames.
 122  */
 123 #define TX_MAX_NUM_DPE          32
 124
 125 /* Delay for the transmit to wait before sending an unfilled NTB frame. */
 126 #define TX_TIMEOUT_NSECS        300000
 127
 128 #define FORMATS_SUPPORTED       (USB_CDC_NCM_NTB16_SUPPORTED |  \
 129                                  USB_CDC_NCM_NTB32_SUPPORTED)
 130
 131 static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
 132         .wLength = cpu_to_le16(sizeof(ntb_parameters)),
 133         .bmNtbFormatsSupported = cpu_to_le16(FORMATS_SUPPORTED),
 134         .dwNtbInMaxSize = cpu_to_le32(NTB_DEFAULT_IN_SIZE),
 135         .wNdpInDivisor = cpu_to_le16(4),
 136         .wNdpInPayloadRemainder = cpu_to_le16(0),
 137         .wNdpInAlignment = cpu_to_le16(4),
 138
 139         .dwNtbOutMaxSize = cpu_to_le32(NTB_OUT_SIZE),
 140         .wNdpOutDivisor = cpu_to_le16(4),
 141         .wNdpOutPayloadRemainder = cpu_to_le16(0),
 142         .wNdpOutAlignment = cpu_to_le16(4),
 143 };
 144
 145 /*
 146  * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
 147  * packet, to simplify cancellation; and a big transfer interval, to
 148  * waste less bandwidth.
 149  */
 150
 151 #define NCM_STATUS_INTERVAL_MS          32
 152 #define NCM_STATUS_BYTECOUNT            16      /* 8 byte header + data */
 153
 154 static struct usb_interface_assoc_descriptor ncm_iad_desc = {
 155         .bLength =              sizeof ncm_iad_desc,
 156         .bDescriptorType =      USB_DT_INTERFACE_ASSOCIATION,
 157
 158         /* .bFirstInterface =   DYNAMIC, */
 159         .bInterfaceCount =      2,      /* control + data */
 160         .bFunctionClass =       USB_CLASS_COMM,
 161         .bFunctionSubClass =    USB_CDC_SUBCLASS_NCM,
 162         .bFunctionProtocol =    USB_CDC_PROTO_NONE,
 163         /* .iFunction =         DYNAMIC */
 164 };
 165
 166 /* interface descriptor: */
 167
 168 static struct usb_interface_descriptor ncm_control_intf = {
 169         .bLength =              sizeof ncm_control_intf,
 170         .bDescriptorType =      USB_DT_INTERFACE,
 171
 172         /* .bInterfaceNumber = DYNAMIC */
 173         .bNumEndpoints =        1,
 174         .bInterfaceClass =      USB_CLASS_COMM,
 175         .bInterfaceSubClass =   USB_CDC_SUBCLASS_NCM,
 176         .bInterfaceProtocol =   USB_CDC_PROTO_NONE,
 177         /* .iInterface = DYNAMIC */
 178 };
 179
 180 static struct usb_cdc_header_desc ncm_header_desc = {
 181         .bLength =              sizeof ncm_header_desc,
 182         .bDescriptorType =      USB_DT_CS_INTERFACE,
 183         .bDescriptorSubType =   USB_CDC_HEADER_TYPE,
 184
 185         .bcdCDC =               cpu_to_le16(0x0110),
 186 };
 187
 188 static struct usb_cdc_union_desc ncm_union_desc = {
 189         .bLength =              sizeof(ncm_union_desc),
 190         .bDescriptorType =      USB_DT_CS_INTERFACE,
 191         .bDescriptorSubType =   USB_CDC_UNION_TYPE,
 192         /* .bMasterInterface0 = DYNAMIC */
 193         /* .bSlaveInterface0 =  DYNAMIC */
 194 };
 195
 196 static struct usb_cdc_ether_desc ecm_desc = {
 197         .bLength =              sizeof ecm_desc,
 198         .bDescriptorType =      USB_DT_CS_INTERFACE,
 199         .bDescriptorSubType =   USB_CDC_ETHERNET_TYPE,
 200
 201         /* this descriptor actually adds value, surprise! */
 202         /* .iMACAddress = DYNAMIC */
 203         .bmEthernetStatistics = cpu_to_le32(0), /* no statistics */
 204         .wMaxSegmentSize =      cpu_to_le16(ETH_FRAME_LEN),
 205         .wNumberMCFilters =     cpu_to_le16(0),
 206         .bNumberPowerFilters =  0,
 207 };
 208
 209 #define NCAPS   (USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
 210
 211 static struct usb_cdc_ncm_desc ncm_desc = {
 212         .bLength =              sizeof ncm_desc,
 213         .bDescriptorType =      USB_DT_CS_INTERFACE,
 214         .bDescriptorSubType =   USB_CDC_NCM_TYPE,
 215
 216         .bcdNcmVersion =        cpu_to_le16(0x0100),
 217         /* can process SetEthernetPacketFilter */
 218         .bmNetworkCapabilities = NCAPS,
 219 };
 220
 221 /* the default data interface has no endpoints ... */
 222
 223 static struct usb_interface_descriptor ncm_data_nop_intf = {
 224         .bLength =              sizeof ncm_data_nop_intf,
 225         .bDescriptorType =      USB_DT_INTERFACE,
 226
 227         .bInterfaceNumber =     1,
 228         .bAlternateSetting =    0,
 229         .bNumEndpoints =        0,
 230         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 231         .bInterfaceSubClass =   0,
 232         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 233         /* .iInterface = DYNAMIC */
 234 };
 235
 236 /* ... but the "real" data interface has two bulk endpoints */
 237
 238 static struct usb_interface_descriptor ncm_data_intf = {
 239         .bLength =              sizeof ncm_data_intf,
 240         .bDescriptorType =      USB_DT_INTERFACE,
 241
 242         .bInterfaceNumber =     1,
 243         .bAlternateSetting =    1,
 244         .bNumEndpoints =        2,
 245         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 246         .bInterfaceSubClass =   0,
 247         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 248         /* .iInterface = DYNAMIC */
 249 };
 250
 251 /* full speed support: */
 252
 253 static struct usb_endpoint_descriptor fs_ncm_notify_desc = {
 254         .bLength =              USB_DT_ENDPOINT_SIZE,
 255         .bDescriptorType =      USB_DT_ENDPOINT,
 256
 257         .bEndpointAddress =     USB_DIR_IN,
 258         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 259         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 260         .bInterval =            NCM_STATUS_INTERVAL_MS,
 261 };
 262
 263 static struct usb_endpoint_descriptor fs_ncm_in_desc = {
 264         .bLength =              USB_DT_ENDPOINT_SIZE,
 265         .bDescriptorType =      USB_DT_ENDPOINT,
 266
 267         .bEndpointAddress =     USB_DIR_IN,
 268         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 269 };
 270
 271 static struct usb_endpoint_descriptor fs_ncm_out_desc = {
 272         .bLength =              USB_DT_ENDPOINT_SIZE,
 273         .bDescriptorType =      USB_DT_ENDPOINT,
 274
 275         .bEndpointAddress =     USB_DIR_OUT,
 276         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 277 };
 278
 279 static struct usb_descriptor_header *ncm_fs_function[] = {
 280         (struct usb_descriptor_header *) &ncm_iad_desc,
 281         /* CDC NCM control descriptors */
 282         (struct usb_descriptor_header *) &ncm_control_intf,
 283         (struct usb_descriptor_header *) &ncm_header_desc,
 284         (struct usb_descriptor_header *) &ncm_union_desc,
 285         (struct usb_descriptor_header *) &ecm_desc,
 286         (struct usb_descriptor_header *) &ncm_desc,
 287         (struct usb_descriptor_header *) &fs_ncm_notify_desc,
 288         /* data interface, altsettings 0 and 1 */
 289         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 290         (struct usb_descriptor_header *) &ncm_data_intf,
 291         (struct usb_descriptor_header *) &fs_ncm_in_desc,
 292         (struct usb_descriptor_header *) &fs_ncm_out_desc,
 293         NULL,
 294 };
 295
 296 /* high speed support: */
 297
 298 static struct usb_endpoint_descriptor hs_ncm_notify_desc = {
 299         .bLength =              USB_DT_ENDPOINT_SIZE,
 300         .bDescriptorType =      USB_DT_ENDPOINT,
 301
 302         .bEndpointAddress =     USB_DIR_IN,
 303         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 304         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 305         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS),
 306 };
 307 static struct usb_endpoint_descriptor hs_ncm_in_desc = {
 308         .bLength =              USB_DT_ENDPOINT_SIZE,
 309         .bDescriptorType =      USB_DT_ENDPOINT,
 310
 311         .bEndpointAddress =     USB_DIR_IN,
 312         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 313         .wMaxPacketSize =       cpu_to_le16(512),
 314 };
 315
 316 static struct usb_endpoint_descriptor hs_ncm_out_desc = {
 317         .bLength =              USB_DT_ENDPOINT_SIZE,
 318         .bDescriptorType =      USB_DT_ENDPOINT,
 319
 320         .bEndpointAddress =     USB_DIR_OUT,
 321         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 322         .wMaxPacketSize =       cpu_to_le16(512),
 323 };
 324
 325 static struct usb_descriptor_header *ncm_hs_function[] = {
 326         (struct usb_descriptor_header *) &ncm_iad_desc,
 327         /* CDC NCM control descriptors */
 328         (struct usb_descriptor_header *) &ncm_control_intf,
 329         (struct usb_descriptor_header *) &ncm_header_desc,
 330         (struct usb_descriptor_header *) &ncm_union_desc,
 331         (struct usb_descriptor_header *) &ecm_desc,
 332         (struct usb_descriptor_header *) &ncm_desc,
 333         (struct usb_descriptor_header *) &hs_ncm_notify_desc,
 334         /* data interface, altsettings 0 and 1 */
 335         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 336         (struct usb_descriptor_header *) &ncm_data_intf,
 337         (struct usb_descriptor_header *) &hs_ncm_in_desc,
 338         (struct usb_descriptor_header *) &hs_ncm_out_desc,
 339         NULL,
 340 };
 341
 342
 343 /* super speed support: */
 344
 345 static struct usb_endpoint_descriptor ss_ncm_notify_desc = {
 346         .bLength =              USB_DT_ENDPOINT_SIZE,
 347         .bDescriptorType =      USB_DT_ENDPOINT,
 348
 349         .bEndpointAddress =     USB_DIR_IN,
 350         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 351         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 352         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS)
 353 };
 354
 355 static struct usb_ss_ep_comp_descriptor ss_ncm_notify_comp_desc = {
 356         .bLength =              sizeof(ss_ncm_notify_comp_desc),
 357         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 358
 359         /* the following 3 values can be tweaked if necessary */
 360         /* .bMaxBurst =         0, */
 361         /* .bmAttributes =      0, */
 362         .wBytesPerInterval =    cpu_to_le16(NCM_STATUS_BYTECOUNT),
 363 };
 364
 365 static struct usb_endpoint_descriptor ss_ncm_in_desc = {
 366         .bLength =              USB_DT_ENDPOINT_SIZE,
 367         .bDescriptorType =      USB_DT_ENDPOINT,
 368
 369         .bEndpointAddress =     USB_DIR_IN,
 370         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 371         .wMaxPacketSize =       cpu_to_le16(1024),
 372 };
 373
 374 static struct usb_endpoint_descriptor ss_ncm_out_desc = {
 375         .bLength =              USB_DT_ENDPOINT_SIZE,
 376         .bDescriptorType =      USB_DT_ENDPOINT,
 377
 378         .bEndpointAddress =     USB_DIR_OUT,
 379         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 380         .wMaxPacketSize =       cpu_to_le16(1024),
 381 };
 382
 383 static struct usb_ss_ep_comp_descriptor ss_ncm_bulk_comp_desc = {
 384         .bLength =              sizeof(ss_ncm_bulk_comp_desc),
 385         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 386
 387         /* the following 2 values can be tweaked if necessary */
 388         /* .bMaxBurst =         0, */
 389         /* .bmAttributes =      0, */
 390 };
 391
 392 static struct usb_descriptor_header *ncm_ss_function[] = {
 393         (struct usb_descriptor_header *) &ncm_iad_desc,
 394         /* CDC NCM control descriptors */
 395         (struct usb_descriptor_header *) &ncm_control_intf,
 396         (struct usb_descriptor_header *) &ncm_header_desc,
 397         (struct usb_descriptor_header *) &ncm_union_desc,
 398         (struct usb_descriptor_header *) &ecm_desc,
 399         (struct usb_descriptor_header *) &ncm_desc,
 400         (struct usb_descriptor_header *) &ss_ncm_notify_desc,
 401         (struct usb_descriptor_header *) &ss_ncm_notify_comp_desc,
 402         /* data interface, altsettings 0 and 1 */
 403         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 404         (struct usb_descriptor_header *) &ncm_data_intf,
 405         (struct usb_descriptor_header *) &ss_ncm_in_desc,
 406         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 407         (struct usb_descriptor_header *) &ss_ncm_out_desc,
 408         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 409         NULL,
 410 };
 411
 412 /* string descriptors: */
 413
 414 #define STRING_CTRL_IDX 0
 415 #define STRING_MAC_IDX  1
 416 #define STRING_DATA_IDX 2
 417 #define STRING_IAD_IDX  3
 418
 419 static struct usb_string ncm_string_defs[] = {
 420         [STRING_CTRL_IDX].s = "CDC Network Control Model (NCM)",
 421         [STRING_MAC_IDX].s = "",
 422         [STRING_DATA_IDX].s = "CDC Network Data",
 423         [STRING_IAD_IDX].s = "CDC NCM",
 424         {  } /* end of list */
 425 };
 426
 427 static struct usb_gadget_strings ncm_string_table = {
 428         .language =             0x0409, /* en-us */
 429         .strings =              ncm_string_defs,
 430 };
 431
 432 static struct usb_gadget_strings *ncm_strings[] = {
 433         &ncm_string_table,
 434         NULL,
 435 };
 436
 437 /*
 438  * Here are options for NCM Datagram Pointer table (NDP) parser.
 439  * There are 2 different formats: NDP16 and NDP32 in the spec (ch. 3),
 440  * in NDP16 offsets and sizes fields are 1 16bit word wide,
 441  * in NDP32 -- 2 16bit words wide. Also signatures are different.
 442  * To make the parser code the same, put the differences in the structure,
 443  * and switch pointers to the structures when the format is changed.
 444  */
 445
 446 struct ndp_parser_opts {
 447         u32             nth_sign;
 448         u32             ndp_sign;
 449         unsigned        nth_size;
 450         unsigned        ndp_size;
 451         unsigned        dpe_size;
 452         unsigned        ndplen_align;
 453         /* sizes in u16 units */
 454         unsigned        dgram_item_len; /* index or length */
 455         unsigned        block_length;
 456         unsigned        ndp_index;
 457         unsigned        reserved1;
 458         unsigned        reserved2;
 459         unsigned        next_ndp_index;
 460 };
 461
 462 #define INIT_NDP16_OPTS {                                       \
 463                 .nth_sign = USB_CDC_NCM_NTH16_SIGN,             \
 464                 .ndp_sign = USB_CDC_NCM_NDP16_NOCRC_SIGN,       \
 465                 .nth_size = sizeof(struct usb_cdc_ncm_nth16),   \
 466                 .ndp_size = sizeof(struct usb_cdc_ncm_ndp16),   \
 467                 .dpe_size = sizeof(struct usb_cdc_ncm_dpe16),   \
 468                 .ndplen_align = 4,                              \
 469                 .dgram_item_len = 1,                            \
 470                 .block_length = 1,                              \
 471                 .ndp_index = 1,                                 \
 472                 .reserved1 = 0,                                 \
 473                 .reserved2 = 0,                                 \
 474                 .next_ndp_index = 1,                            \
 475         }
 476
 477
 478 #define INIT_NDP32_OPTS {                                       \
 479                 .nth_sign = USB_CDC_NCM_NTH32_SIGN,             \
 480                 .ndp_sign = USB_CDC_NCM_NDP32_NOCRC_SIGN,       \
 481                 .nth_size = sizeof(struct usb_cdc_ncm_nth32),   \
 482                 .ndp_size = sizeof(struct usb_cdc_ncm_ndp32),   \
 483                 .dpe_size = sizeof(struct usb_cdc_ncm_dpe32),   \
 484                 .ndplen_align = 8,                              \
 485                 .dgram_item_len = 2,                            \
 486                 .block_length = 2,                              \
 487                 .ndp_index = 2,                                 \
 488                 .reserved1 = 1,                                 \
 489                 .reserved2 = 2,                                 \
 490                 .next_ndp_index = 2,                            \
 491         }
 492
 493 static const struct ndp_parser_opts ndp16_opts = INIT_NDP16_OPTS;
 494 static const struct ndp_parser_opts ndp32_opts = INIT_NDP32_OPTS;
 495
 496 static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
 497 {
 498         switch (size) {
 499         case 1:
 500                 put_unaligned_le16((u16)val, *p);
 501                 break;
 502         case 2:
 503                 put_unaligned_le32((u32)val, *p);
 504
 505                 break;
 506         default:
 507                 BUG();
 508         }
 509
 510         *p += size;
 511 }
 512
 513 static inline unsigned get_ncm(__le16 **p, unsigned size)
 514 {
 515         unsigned tmp;
 516
 517         switch (size) {
 518         case 1:
 519                 tmp = get_unaligned_le16(*p);
 520                 break;
 521         case 2:
 522                 tmp = get_unaligned_le32(*p);
 523                 break;
 524         default:
 525                 BUG();
 526         }
 527
 528         *p += size;
 529         return tmp;
 530 }
 531
 532 /*-------------------------------------------------------------------------*/
 533
 534 static inline void ncm_reset_values(struct f_ncm *ncm)
 535 {
 536         ncm->parser_opts = &ndp16_opts;
 537         ncm->is_crc = false;
 538         ncm->port.cdc_filter = DEFAULT_FILTER;
 539
 540         /* doesn't make sense for ncm, fixed size used */
 541         ncm->port.header_len = 0;
 542
 543         ncm->port.fixed_out_len = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
 544         ncm->port.fixed_in_len = NTB_DEFAULT_IN_SIZE;
 545 }
 546
 547 /*
 548  * Context: ncm->lock held
 549  */
 550 static void ncm_do_notify(struct f_ncm *ncm)
 551 {
 552         struct usb_request              *req = ncm->notify_req;
 553         struct usb_cdc_notification     *event;
 554         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 555         __le32                          *data;
 556         int                             status;
 557
 558         /* notification already in flight? */
 559         if (atomic_read(&ncm->notify_count))
 560                 return;
 561
 562         event = req->buf;
 563         switch (ncm->notify_state) {
 564         case NCM_NOTIFY_NONE:
 565                 return;
 566
 567         case NCM_NOTIFY_CONNECT:
 568                 event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
 569                 if (ncm->is_open)
 570                         event->wValue = cpu_to_le16(1);
 571                 else
 572                         event->wValue = cpu_to_le16(0);
 573                 event->wLength = 0;
 574                 req->length = sizeof *event;
 575
 576                 DBG(cdev, "notify connect %s\n",
 577                                 ncm->is_open ? "true" : "false");
 578                 ncm->notify_state = NCM_NOTIFY_NONE;
 579                 break;
 580
 581         case NCM_NOTIFY_SPEED:
 582                 event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
 583                 event->wValue = cpu_to_le16(0);
 584                 event->wLength = cpu_to_le16(8);
 585                 req->length = NCM_STATUS_BYTECOUNT;
 586
 587                 /* SPEED_CHANGE data is up/down speeds in bits/sec */
 588                 data = req->buf + sizeof *event;
 589                 data[0] = cpu_to_le32(ncm_bitrate(cdev->gadget));
 590                 data[1] = data[0];
 591
 592                 DBG(cdev, "notify speed %u\n", ncm_bitrate(cdev->gadget));
 593                 ncm->notify_state = NCM_NOTIFY_CONNECT;
 594                 break;
 595         }
 596         event->bmRequestType = 0xA1;
 597         event->wIndex = cpu_to_le16(ncm->ctrl_id);
 598
 599         atomic_inc(&ncm->notify_count);
 600
 601         /*
 602          * In double buffering if there is a space in FIFO,
 603          * completion callback can be called right after the call,
 604          * so unlocking
 605          */
 606         spin_unlock(&ncm->lock);
 607         status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC);
 608         spin_lock(&ncm->lock);
 609         if (status < 0) {
 610                 atomic_dec(&ncm->notify_count);
 611                 DBG(cdev, "notify --> %d\n", status);
 612         }
 613 }
 614
 615 /*
 616  * Context: ncm->lock held
 617  */
 618 static void ncm_notify(struct f_ncm *ncm)
 619 {
 620         /*
 621          * NOTE on most versions of Linux, host side cdc-ethernet
 622          * won't listen for notifications until its netdevice opens.
 623          * The first notification then sits in the FIFO for a long
 624          * time, and the second one is queued.
 625          *
 626          * If ncm_notify() is called before the second (CONNECT)
 627          * notification is sent, then it will reset to send the SPEED
 628          * notificaion again (and again, and again), but it's not a problem
 629          */
 630         ncm->notify_state = NCM_NOTIFY_SPEED;
 631         ncm_do_notify(ncm);
 632 }
 633
 634 static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req)
 635 {
 636         struct f_ncm                    *ncm = req->context;
 637         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 638         struct usb_cdc_notification     *event = req->buf;
 639
 640         spin_lock(&ncm->lock);
 641         switch (req->status) {
 642         case 0:
 643                 VDBG(cdev, "Notification %02x sent\n",
 644                      event->bNotificationType);
 645                 atomic_dec(&ncm->notify_count);
 646                 break;
 647         case -ECONNRESET:
 648         case -ESHUTDOWN:
 649                 atomic_set(&ncm->notify_count, 0);
 650                 ncm->notify_state = NCM_NOTIFY_NONE;
 651                 break;
 652         default:
 653                 DBG(cdev, "event %02x --> %d\n",
 654                         event->bNotificationType, req->status);
 655                 atomic_dec(&ncm->notify_count);
 656                 break;
 657         }
 658         ncm_do_notify(ncm);
 659         spin_unlock(&ncm->lock);
 660 }
 661
 662 static void ncm_ep0out_complete(struct usb_ep *ep, struct usb_request *req)
 663 {
 664         /* now for SET_NTB_INPUT_SIZE only */
 665         unsigned                in_size;
 666         struct usb_function     *f = req->context;
 667         struct f_ncm            *ncm = func_to_ncm(f);
 668         struct usb_composite_dev *cdev = f->config->cdev;
 669
 670         req->context = NULL;
 671         if (req->status || req->actual != req->length) {
 672                 DBG(cdev, "Bad control-OUT transfer\n");
 673                 goto invalid;
 674         }
 675
 676         in_size = get_unaligned_le32(req->buf);
 677         if (in_size < USB_CDC_NCM_NTB_MIN_IN_SIZE ||
 678             in_size > le32_to_cpu(ntb_parameters.dwNtbInMaxSize)) {
 679                 DBG(cdev, "Got wrong INPUT SIZE (%d) from host\n", in_size);
 680                 goto invalid;
 681         }
 682
 683         ncm->port.fixed_in_len = in_size;
 684         VDBG(cdev, "Set NTB INPUT SIZE %d\n", in_size);
 685         return;
 686
 687 invalid:
 688         usb_ep_set_halt(ep);
 689         return;
 690 }
 691
 692 static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 693 {
 694         struct f_ncm            *ncm = func_to_ncm(f);
 695         struct usb_composite_dev *cdev = f->config->cdev;
 696         struct usb_request      *req = cdev->req;
 697         int                     value = -EOPNOTSUPP;
 698         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 699         u16                     w_value = le16_to_cpu(ctrl->wValue);
 700         u16                     w_length = le16_to_cpu(ctrl->wLength);
 701
 702         /*
 703          * composite driver infrastructure handles everything except
 704          * CDC class messages; interface activation uses set_alt().
 705          */
 706         switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 707         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 708                         | USB_CDC_SET_ETHERNET_PACKET_FILTER:
 709                 /*
 710                  * see 6.2.30: no data, wIndex = interface,
 711                  * wValue = packet filter bitmap
 712                  */
 713                 if (w_length != 0 || w_index != ncm->ctrl_id)
 714                         goto invalid;
 715                 DBG(cdev, "packet filter %02x\n", w_value);
 716                 /*
 717                  * REVISIT locking of cdc_filter.  This assumes the UDC
 718                  * driver won't have a concurrent packet TX irq running on
 719                  * another CPU; or that if it does, this write is atomic...
 720                  */
 721                 ncm->port.cdc_filter = w_value;
 722                 value = 0;
 723                 break;
 724         /*
 725          * and optionally:
 726          * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
 727          * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
 728          * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
 729          * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
 730          * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
 731          * case USB_CDC_GET_ETHERNET_STATISTIC:
 732          */
 733
 734         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 735                 | USB_CDC_GET_NTB_PARAMETERS:
 736
 737                 if (w_length == 0 || w_value != 0 || w_index != ncm->ctrl_id)
 738                         goto invalid;
 739                 value = w_length > sizeof ntb_parameters ?
 740                         sizeof ntb_parameters : w_length;
 741                 memcpy(req->buf, &ntb_parameters, value);
 742                 VDBG(cdev, "Host asked NTB parameters\n");
 743                 break;
 744
 745         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 746                 | USB_CDC_GET_NTB_INPUT_SIZE:
 747
 748                 if (w_length < 4 || w_value != 0 || w_index != ncm->ctrl_id)
 749                         goto invalid;
 750                 put_unaligned_le32(ncm->port.fixed_in_len, req->buf);
 751                 value = 4;
 752                 VDBG(cdev, "Host asked INPUT SIZE, sending %d\n",
 753                      ncm->port.fixed_in_len);
 754                 break;
 755
 756         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 757                 | USB_CDC_SET_NTB_INPUT_SIZE:
 758         {
 759                 if (w_length != 4 || w_value != 0 || w_index != ncm->ctrl_id)
 760                         goto invalid;
 761                 req->complete = ncm_ep0out_complete;
 762                 req->length = w_length;
 763                 req->context = f;
 764
 765                 value = req->length;
 766                 break;
 767         }
 768
 769         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 770                 | USB_CDC_GET_NTB_FORMAT:
 771         {
 772                 uint16_t format;
 773
 774                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 775                         goto invalid;
 776                 format = (ncm->parser_opts == &ndp16_opts) ? 0x0000 : 0x0001;
 777                 put_unaligned_le16(format, req->buf);
 778                 value = 2;
 779                 VDBG(cdev, "Host asked NTB FORMAT, sending %d\n", format);
 780                 break;
 781         }
 782
 783         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 784                 | USB_CDC_SET_NTB_FORMAT:
 785         {
 786                 if (w_length != 0 || w_index != ncm->ctrl_id)
 787                         goto invalid;
 788                 switch (w_value) {
 789                 case 0x0000:
 790                         ncm->parser_opts = &ndp16_opts;
 791                         DBG(cdev, "NCM16 selected\n");
 792                         break;
 793                 case 0x0001:
 794                         ncm->parser_opts = &ndp32_opts;
 795                         DBG(cdev, "NCM32 selected\n");
 796                         break;
 797                 default:
 798                         goto invalid;
 799                 }
 800                 value = 0;
 801                 break;
 802         }
 803         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 804                 | USB_CDC_GET_CRC_MODE:
 805         {
 806                 uint16_t is_crc;
 807
 808                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 809                         goto invalid;
 810                 is_crc = ncm->is_crc ? 0x0001 : 0x0000;
 811                 put_unaligned_le16(is_crc, req->buf);
 812                 value = 2;
 813                 VDBG(cdev, "Host asked CRC MODE, sending %d\n", is_crc);
 814                 break;
 815         }
 816
 817         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 818                 | USB_CDC_SET_CRC_MODE:
 819         {
 820                 int ndp_hdr_crc = 0;
 821
 822                 if (w_length != 0 || w_index != ncm->ctrl_id)
 823                         goto invalid;
 824                 switch (w_value) {
 825                 case 0x0000:
 826                         ncm->is_crc = false;
 827                         ndp_hdr_crc = NCM_NDP_HDR_NOCRC;
 828                         DBG(cdev, "non-CRC mode selected\n");
 829                         break;
 830                 case 0x0001:
 831                         ncm->is_crc = true;
 832                         ndp_hdr_crc = NCM_NDP_HDR_CRC;
 833                         DBG(cdev, "CRC mode selected\n");
 834                         break;
 835                 default:
 836                         goto invalid;
 837                 }
 838                 ncm->ndp_sign = ncm->parser_opts->ndp_sign | ndp_hdr_crc;
 839                 value = 0;
 840                 break;
 841         }
 842
 843         /* and disabled in ncm descriptor: */
 844         /* case USB_CDC_GET_NET_ADDRESS: */
 845         /* case USB_CDC_SET_NET_ADDRESS: */
 846         /* case USB_CDC_GET_MAX_DATAGRAM_SIZE: */
 847         /* case USB_CDC_SET_MAX_DATAGRAM_SIZE: */
 848
 849         default:
 850 invalid:
 851                 DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 852                         ctrl->bRequestType, ctrl->bRequest,
 853                         w_value, w_index, w_length);
 854         }
 855
 856         /* respond with data transfer or status phase? */
 857         if (value >= 0) {
 858                 DBG(cdev, "ncm req%02x.%02x v%04x i%04x l%d\n",
 859                         ctrl->bRequestType, ctrl->bRequest,
 860                         w_value, w_index, w_length);
 861                 req->zero = 0;
 862                 req->length = value;
 863                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 864                 if (value < 0)
 865                         ERROR(cdev, "ncm req %02x.%02x response err %d\n",
 866                                         ctrl->bRequestType, ctrl->bRequest,
 867                                         value);
 868         }
 869
 870         /* device either stalls (value < 0) or reports success */
 871         return value;
 872 }
 873
 874
 875 static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 876 {
 877         struct f_ncm            *ncm = func_to_ncm(f);
 878         struct usb_composite_dev *cdev = f->config->cdev;
 879
 880         /* Control interface has only altsetting 0 */
 881         if (intf == ncm->ctrl_id) {
 882                 if (alt != 0)
 883                         goto fail;
 884
 885                 DBG(cdev, "reset ncm control %d\n", intf);
 886                 usb_ep_disable(ncm->notify);
 887
 888                 if (!(ncm->notify->desc)) {
 889                         DBG(cdev, "init ncm ctrl %d\n", intf);
 890                         if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
 891                                 goto fail;
 892                 }
 893                 usb_ep_enable(ncm->notify);
 894
 895         /* Data interface has two altsettings, 0 and 1 */
 896         } else if (intf == ncm->data_id) {
 897                 if (alt > 1)
 898                         goto fail;
 899
 900                 if (ncm->port.in_ep->enabled) {
 901                         DBG(cdev, "reset ncm\n");
 902                         ncm->timer_stopping = true;
 903                         ncm->netdev = NULL;
 904                         gether_disconnect(&ncm->port);
 905                         ncm_reset_values(ncm);
 906                 }
 907
 908                 /*
 909                  * CDC Network only sends data in non-default altsettings.
 910                  * Changing altsettings resets filters, statistics, etc.
 911                  */
 912                 if (alt == 1) {
 913                         struct net_device       *net;
 914
 915                         if (!ncm->port.in_ep->desc ||
 916                             !ncm->port.out_ep->desc) {
 917                                 DBG(cdev, "init ncm\n");
 918                                 if (config_ep_by_speed(cdev->gadget, f,
 919                                                        ncm->port.in_ep) ||
 920                                     config_ep_by_speed(cdev->gadget, f,
 921                                                        ncm->port.out_ep)) {
 922                                         ncm->port.in_ep->desc = NULL;
 923                                         ncm->port.out_ep->desc = NULL;
 924                                         goto fail;
 925                                 }
 926                         }
 927
 928                         /* TODO */
 929                         /* Enable zlps by default for NCM conformance;
 930                          * override for musb_hdrc (avoids txdma ovhead)
 931                          */
 932                         ncm->port.is_zlp_ok =
 933                                 gadget_is_zlp_supported(cdev->gadget);
 934                         ncm->port.cdc_filter = DEFAULT_FILTER;
 935                         DBG(cdev, "activate ncm\n");
 936                         net = gether_connect(&ncm->port);
 937                         if (IS_ERR(net))
 938                                 return PTR_ERR(net);
 939                         ncm->netdev = net;
 940                         ncm->timer_stopping = false;
 941                 }
 942
 943                 spin_lock(&ncm->lock);
 944                 ncm_notify(ncm);
 945                 spin_unlock(&ncm->lock);
 946         } else
 947                 goto fail;
 948
 949         return 0;
 950 fail:
 951         return -EINVAL;
 952 }
 953
 954 /*
 955  * Because the data interface supports multiple altsettings,
 956  * this NCM function *MUST* implement a get_alt() method.
 957  */
 958 static int ncm_get_alt(struct usb_function *f, unsigned intf)
 959 {
 960         struct f_ncm            *ncm = func_to_ncm(f);
 961
 962         if (intf == ncm->ctrl_id)
 963                 return 0;
 964         return ncm->port.in_ep->enabled ? 1 : 0;
 965 }
 966
 967 static struct sk_buff *package_for_tx(struct f_ncm *ncm)
 968 {
 969         __le16          *ntb_iter;
 970         struct sk_buff  *skb2 = NULL;
 971         unsigned        ndp_pad;
 972         unsigned        ndp_index;
 973         unsigned        new_len;
 974
 975         const struct ndp_parser_opts *opts = ncm->parser_opts;
 976         const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
 977         const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
 978
 979         /* Stop the timer */
 980         hrtimer_try_to_cancel(&ncm->task_timer);
 981
 982         ndp_pad = ALIGN(ncm->skb_tx_data->len, ndp_align) -
 983                         ncm->skb_tx_data->len;
 984         ndp_index = ncm->skb_tx_data->len + ndp_pad;
 985         new_len = ndp_index + dgram_idx_len + ncm->skb_tx_ndp->len;
 986
 987         /* Set the final BlockLength and wNdpIndex */
 988         ntb_iter = (void *) ncm->skb_tx_data->data;
 989         /* Increment pointer to BlockLength */
 990         ntb_iter += 2 + 1 + 1;
 991         put_ncm(&ntb_iter, opts->block_length, new_len);
 992         put_ncm(&ntb_iter, opts->ndp_index, ndp_index);
 993
 994         /* Set the final NDP wLength */
 995         new_len = opts->ndp_size +
 996                         (ncm->ndp_dgram_count * dgram_idx_len);
 997         ncm->ndp_dgram_count = 0;
 998         /* Increment from start to wLength */
 999         ntb_iter = (void *) ncm->skb_tx_ndp->data;
1000         ntb_iter += 2;
1001         put_unaligned_le16(new_len, ntb_iter);
1002
1003         /* Merge the skbs */
1004         swap(skb2, ncm->skb_tx_data);
1005         if (ncm->skb_tx_data) {
1006                 dev_consume_skb_any(ncm->skb_tx_data);
1007                 ncm->skb_tx_data = NULL;
1008         }
1009
1010         /* Insert NDP alignment. */
1011         skb_put_zero(skb2, ndp_pad);
1012
1013         /* Copy NTB across. */
1014         skb_put_data(skb2, ncm->skb_tx_ndp->data, ncm->skb_tx_ndp->len);
1015         dev_consume_skb_any(ncm->skb_tx_ndp);
1016         ncm->skb_tx_ndp = NULL;
1017
1018         /* Insert zero'd datagram. */
1019         skb_put_zero(skb2, dgram_idx_len);
1020
1021         return skb2;
1022 }
1023
1024 static struct sk_buff *ncm_wrap_ntb(struct gether *port,
1025                                     struct sk_buff *skb)
1026 {
1027         struct f_ncm    *ncm = func_to_ncm(&port->func);
1028         struct sk_buff  *skb2 = NULL;
1029         int             ncb_len = 0;
1030         __le16          *ntb_data;
1031         __le16          *ntb_ndp;
1032         int             dgram_pad;
1033
1034         unsigned        max_size = ncm->port.fixed_in_len;
1035         const struct ndp_parser_opts *opts = ncm->parser_opts;
1036         const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
1037         const int div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
1038         const int rem = le16_to_cpu(ntb_parameters.wNdpInPayloadRemainder);
1039         const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
1040
1041         if (!skb && !ncm->skb_tx_data)
1042                 return NULL;
1043
1044         if (skb) {
1045                 /* Add the CRC if required up front */
1046                 if (ncm->is_crc) {
1047                         uint32_t        crc;
1048                         __le16          *crc_pos;
1049
1050                         crc = ~crc32_le(~0,
1051                                         skb->data,
1052                                         skb->len);
1053                         crc_pos = skb_put(skb, sizeof(uint32_t));
1054                         put_unaligned_le32(crc, crc_pos);
1055                 }
1056
1057                 /* If the new skb is too big for the current NCM NTB then
1058                  * set the current stored skb to be sent now and clear it
1059                  * ready for new data.
1060                  * NOTE: Assume maximum align for speed of calculation.
1061                  */
1062                 if (ncm->skb_tx_data
1063                     && (ncm->ndp_dgram_count >= TX_MAX_NUM_DPE
1064                     || (ncm->skb_tx_data->len +
1065                     div + rem + skb->len +
1066                     ncm->skb_tx_ndp->len + ndp_align + (2 * dgram_idx_len))
1067                     > max_size)) {
1068                         skb2 = package_for_tx(ncm);
1069                         if (!skb2)
1070                                 goto err;
1071                 }
1072
1073                 if (!ncm->skb_tx_data) {
1074                         ncb_len = opts->nth_size;
1075                         dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1076                         ncb_len += dgram_pad;
1077
1078                         /* Create a new skb for the NTH and datagrams. */
1079                         ncm->skb_tx_data = alloc_skb(max_size, GFP_ATOMIC);
1080                         if (!ncm->skb_tx_data)
1081                                 goto err;
1082
1083                         ncm->skb_tx_data->dev = ncm->netdev;
1084                         ntb_data = skb_put_zero(ncm->skb_tx_data, ncb_len);
1085                         /* dwSignature */
1086                         put_unaligned_le32(opts->nth_sign, ntb_data);
1087                         ntb_data += 2;
1088                         /* wHeaderLength */
1089                         put_unaligned_le16(opts->nth_size, ntb_data++);
1090
1091                         /* Allocate an skb for storing the NDP,
1092                          * TX_MAX_NUM_DPE should easily suffice for a
1093                          * 16k packet.
1094                          */
1095                         ncm->skb_tx_ndp = alloc_skb((int)(opts->ndp_size
1096                                                     + opts->dpe_size
1097                                                     * TX_MAX_NUM_DPE),
1098                                                     GFP_ATOMIC);
1099                         if (!ncm->skb_tx_ndp)
1100                                 goto err;
1101
1102                         ncm->skb_tx_ndp->dev = ncm->netdev;
1103                         ntb_ndp = skb_put(ncm->skb_tx_ndp, opts->ndp_size);
1104                         memset(ntb_ndp, 0, ncb_len);
1105                         /* dwSignature */
1106                         put_unaligned_le32(ncm->ndp_sign, ntb_ndp);
1107                         ntb_ndp += 2;
1108
1109                         /* There is always a zeroed entry */
1110                         ncm->ndp_dgram_count = 1;
1111
1112                         /* Note: we skip opts->next_ndp_index */
1113                 }
1114
1115                 /* Delay the timer. */
1116                 hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
1117                               HRTIMER_MODE_REL);
1118
1119                 /* Add the datagram position entries */
1120                 ntb_ndp = skb_put_zero(ncm->skb_tx_ndp, dgram_idx_len);
1121
1122                 ncb_len = ncm->skb_tx_data->len;
1123                 dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1124                 ncb_len += dgram_pad;
1125
1126                 /* (d)wDatagramIndex */
1127                 put_ncm(&ntb_ndp, opts->dgram_item_len, ncb_len);
1128                 /* (d)wDatagramLength */
1129                 put_ncm(&ntb_ndp, opts->dgram_item_len, skb->len);
1130                 ncm->ndp_dgram_count++;
1131
1132                 /* Add the new data to the skb */
1133                 skb_put_zero(ncm->skb_tx_data, dgram_pad);
1134                 skb_put_data(ncm->skb_tx_data, skb->data, skb->len);
1135                 dev_consume_skb_any(skb);
1136                 skb = NULL;
1137
1138         } else if (ncm->skb_tx_data && ncm->timer_force_tx) {
1139                 /* If the tx was requested because of a timeout then send */
1140                 skb2 = package_for_tx(ncm);
1141                 if (!skb2)
1142                         goto err;
1143         }
1144
1145         return skb2;
1146
1147 err:
1148         ncm->netdev->stats.tx_dropped++;
1149
1150         if (skb)
1151                 dev_kfree_skb_any(skb);
1152         if (ncm->skb_tx_data)
1153                 dev_kfree_skb_any(ncm->skb_tx_data);
1154         if (ncm->skb_tx_ndp)
1155                 dev_kfree_skb_any(ncm->skb_tx_ndp);
1156
1157         return NULL;
1158 }
1159
1160 /*
1161  * This transmits the NTB if there are frames waiting.
1162  */
1163 static void ncm_tx_tasklet(unsigned long data)
1164 {
1165         struct f_ncm    *ncm = (void *)data;
1166
1167         if (ncm->timer_stopping)
1168                 return;
1169
1170         /* Only send if data is available. */
1171         if (ncm->skb_tx_data) {
1172                 ncm->timer_force_tx = true;
1173
1174                 /* XXX This allowance of a NULL skb argument to ndo_start_xmit
1175                  * XXX is not sane.  The gadget layer should be redesigned so
1176                  * XXX that the dev->wrap() invocations to build SKBs is transparent
1177                  * XXX and performed in some way outside of the ndo_start_xmit
1178                  * XXX interface.
1179                  */
1180                 ncm->netdev->netdev_ops->ndo_start_xmit(NULL, ncm->netdev);
1181
1182                 ncm->timer_force_tx = false;
1183         }
1184 }
1185
1186 /*
1187  * The transmit should only be run if no skb data has been sent
1188  * for a certain duration.
1189  */
1190 static enum hrtimer_restart ncm_tx_timeout(struct hrtimer *data)
1191 {
1192         struct f_ncm *ncm = container_of(data, struct f_ncm, task_timer);
1193         tasklet_schedule(&ncm->tx_tasklet);
1194         return HRTIMER_NORESTART;
1195 }
1196
1197 static int ncm_unwrap_ntb(struct gether *port,
1198                           struct sk_buff *skb,
1199                           struct sk_buff_head *list)
1200 {
1201         struct f_ncm    *ncm = func_to_ncm(&port->func);
1202         __le16          *tmp = (void *) skb->data;
1203         unsigned        index, index2;
1204         int             ndp_index;
1205         unsigned        dg_len, dg_len2;
1206         unsigned        ndp_len;
1207         unsigned        block_len;
1208         struct sk_buff  *skb2;
1209         int             ret = -EINVAL;
1210         unsigned        ntb_max = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
1211         unsigned        frame_max = le16_to_cpu(ecm_desc.wMaxSegmentSize);
1212         const struct ndp_parser_opts *opts = ncm->parser_opts;
1213         unsigned        crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
1214         int             dgram_counter;
1215
1216         /* dwSignature */
1217         if (get_unaligned_le32(tmp) != opts->nth_sign) {
1218                 INFO(port->func.config->cdev, "Wrong NTH SIGN, skblen %d\n",
1219                         skb->len);
1220                 print_hex_dump(KERN_INFO, "HEAD:", DUMP_PREFIX_ADDRESS, 32, 1,
1221                                skb->data, 32, false);
1222
1223                 goto err;
1224         }
1225         tmp += 2;
1226         /* wHeaderLength */
1227         if (get_unaligned_le16(tmp++) != opts->nth_size) {
1228                 INFO(port->func.config->cdev, "Wrong NTB headersize\n");
1229                 goto err;
1230         }
1231         tmp++; /* skip wSequence */
1232
1233         block_len = get_ncm(&tmp, opts->block_length);
1234         /* (d)wBlockLength */
1235         if (block_len > ntb_max) {
1236                 INFO(port->func.config->cdev, "OUT size exceeded\n");
1237                 goto err;
1238         }
1239
1240         ndp_index = get_ncm(&tmp, opts->ndp_index);
1241
1242         /* Run through all the NDP's in the NTB */
1243         do {
1244                 /*
1245                  * NCM 3.2
1246                  * dwNdpIndex
1247                  */
1248                 if (((ndp_index % 4) != 0) ||
1249                                 (ndp_index < opts->nth_size) ||
1250                                 (ndp_index > (block_len -
1251                                               opts->ndp_size))) {
1252                         INFO(port->func.config->cdev, "Bad index: %#X\n",
1253                              ndp_index);
1254                         goto err;
1255                 }
1256
1257                 /*
1258                  * walk through NDP
1259                  * dwSignature
1260                  */
1261                 tmp = (void *)(skb->data + ndp_index);
1262                 if (get_unaligned_le32(tmp) != ncm->ndp_sign) {
1263                         INFO(port->func.config->cdev, "Wrong NDP SIGN\n");
1264                         goto err;
1265                 }
1266                 tmp += 2;
1267
1268                 ndp_len = get_unaligned_le16(tmp++);
1269                 /*
1270                  * NCM 3.3.1
1271                  * wLength
1272                  * entry is 2 items
1273                  * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
1274                  * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
1275                  * Each entry is a dgram index and a dgram length.
1276                  */
1277                 if ((ndp_len < opts->ndp_size
1278                                 + 2 * 2 * (opts->dgram_item_len * 2)) ||
1279                                 (ndp_len % opts->ndplen_align != 0)) {
1280                         INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
1281                              ndp_len);
1282                         goto err;
1283                 }
1284                 tmp += opts->reserved1;
1285                 /* Check for another NDP (d)wNextNdpIndex */
1286                 ndp_index = get_ncm(&tmp, opts->next_ndp_index);
1287                 tmp += opts->reserved2;
1288
1289                 ndp_len -= opts->ndp_size;
1290                 index2 = get_ncm(&tmp, opts->dgram_item_len);
1291                 dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1292                 dgram_counter = 0;
1293
1294                 do {
1295                         index = index2;
1296                         /* wDatagramIndex[0] */
1297                         if ((index < opts->nth_size) ||
1298                                         (index > block_len - opts->dpe_size)) {
1299                                 INFO(port->func.config->cdev,
1300                                      "Bad index: %#X\n", index);
1301                                 goto err;
1302                         }
1303
1304                         dg_len = dg_len2;
1305                         /*
1306                          * wDatagramLength[0]
1307                          * ethernet hdr + crc or larger than max frame size
1308                          */
1309                         if ((dg_len < 14 + crc_len) ||
1310                                         (dg_len > frame_max)) {
1311                                 INFO(port->func.config->cdev,
1312                                      "Bad dgram length: %#X\n", dg_len);
1313                                 goto err;
1314                         }
1315                         if (ncm->is_crc) {
1316                                 uint32_t crc, crc2;
1317
1318                                 crc = get_unaligned_le32(skb->data +
1319                                                          index + dg_len -
1320                                                          crc_len);
1321                                 crc2 = ~crc32_le(~0,
1322                                                  skb->data + index,
1323                                                  dg_len - crc_len);
1324                                 if (crc != crc2) {
1325                                         INFO(port->func.config->cdev,
1326                                              "Bad CRC\n");
1327                                         goto err;
1328                                 }
1329                         }
1330
1331                         index2 = get_ncm(&tmp, opts->dgram_item_len);
1332                         dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1333
1334                         /* wDatagramIndex[1] */
1335                         if (index2 > block_len - opts->dpe_size) {
1336                                 INFO(port->func.config->cdev,
1337                                      "Bad index: %#X\n", index2);
1338                                 goto err;
1339                         }
1340
1341                         /*
1342                          * Copy the data into a new skb.
1343                          * This ensures the truesize is correct
1344                          */
1345                         skb2 = netdev_alloc_skb_ip_align(ncm->netdev,
1346                                                          dg_len - crc_len);
1347                         if (skb2 == NULL)
1348                                 goto err;
1349                         skb_put_data(skb2, skb->data + index,
1350                                      dg_len - crc_len);
1351
1352                         skb_queue_tail(list, skb2);
1353
1354                         ndp_len -= 2 * (opts->dgram_item_len * 2);
1355
1356                         dgram_counter++;
1357                         if (index2 == 0 || dg_len2 == 0)
1358                                 break;
1359                 } while (ndp_len > 2 * (opts->dgram_item_len * 2));
1360         } while (ndp_index);
1361
1362         dev_consume_skb_any(skb);
1363
1364         VDBG(port->func.config->cdev,
1365              "Parsed NTB with %d frames\n", dgram_counter);
1366         return 0;
1367 err:
1368         skb_queue_purge(list);
1369         dev_kfree_skb_any(skb);
1370         return ret;
1371 }
1372
1373 static void ncm_disable(struct usb_function *f)
1374 {
1375         struct f_ncm            *ncm = func_to_ncm(f);
1376         struct usb_composite_dev *cdev = f->config->cdev;
1377
1378         DBG(cdev, "ncm deactivated\n");
1379
1380         if (ncm->port.in_ep->enabled) {
1381                 ncm->timer_stopping = true;
1382                 ncm->netdev = NULL;
1383                 gether_disconnect(&ncm->port);
1384         }
1385
1386         if (ncm->notify->enabled) {
1387                 usb_ep_disable(ncm->notify);
1388                 ncm->notify->desc = NULL;
1389         }
1390 }
1391
1392 /*-------------------------------------------------------------------------*/
1393
1394 /*
1395  * Callbacks let us notify the host about connect/disconnect when the
1396  * net device is opened or closed.
1397  *
1398  * For testing, note that link states on this side include both opened
1399  * and closed variants of:
1400  *
1401  *   - disconnected/unconfigured
1402  *   - configured but inactive (data alt 0)
1403  *   - configured and active (data alt 1)
1404  *
1405  * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
1406  * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
1407  * imply the host is actually polling the notification endpoint, and
1408  * likewise that "active" doesn't imply it's actually using the data
1409  * endpoints for traffic.
1410  */
1411
1412 static void ncm_open(struct gether *geth)
1413 {
1414         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1415
1416         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1417
1418         spin_lock(&ncm->lock);
1419         ncm->is_open = true;
1420         ncm_notify(ncm);
1421         spin_unlock(&ncm->lock);
1422 }
1423
1424 static void ncm_close(struct gether *geth)
1425 {
1426         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1427
1428         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1429
1430         spin_lock(&ncm->lock);
1431         ncm->is_open = false;
1432         ncm_notify(ncm);
1433         spin_unlock(&ncm->lock);
1434 }
1435
1436 /*-------------------------------------------------------------------------*/
1437
1438 /* ethernet function driver setup/binding */
1439
1440 static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
1441 {
1442         struct usb_composite_dev *cdev = c->cdev;
1443         struct f_ncm            *ncm = func_to_ncm(f);
1444         struct usb_string       *us;
1445         int                     status;
1446         struct usb_ep           *ep;
1447         struct f_ncm_opts       *ncm_opts;
1448
1449         if (!can_support_ecm(cdev->gadget))
1450                 return -EINVAL;
1451
1452         ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1453         /*
1454          * in drivers/usb/gadget/configfs.c:configfs_composite_bind()
1455          * configurations are bound in sequence with list_for_each_entry,
1456          * in each configuration its functions are bound in sequence
1457          * with list_for_each_entry, so we assume no race condition
1458          * with regard to ncm_opts->bound access
1459          */
1460         if (!ncm_opts->bound) {
1461                 mutex_lock(&ncm_opts->lock);
1462                 gether_set_gadget(ncm_opts->net, cdev->gadget);
1463                 status = gether_register_netdev(ncm_opts->net);
1464                 mutex_unlock(&ncm_opts->lock);
1465                 if (status)
1466                         return status;
1467                 ncm_opts->bound = true;
1468         }
1469         us = usb_gstrings_attach(cdev, ncm_strings,
1470                                  ARRAY_SIZE(ncm_string_defs));
1471         if (IS_ERR(us))
1472                 return PTR_ERR(us);
1473         ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
1474         ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
1475         ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
1476         ecm_desc.iMACAddress = us[STRING_MAC_IDX].id;
1477         ncm_iad_desc.iFunction = us[STRING_IAD_IDX].id;
1478
1479         /* allocate instance-specific interface IDs */
1480         status = usb_interface_id(c, f);
1481         if (status < 0)
1482                 goto fail;
1483         ncm->ctrl_id = status;
1484         ncm_iad_desc.bFirstInterface = status;
1485
1486         ncm_control_intf.bInterfaceNumber = status;
1487         ncm_union_desc.bMasterInterface0 = status;
1488
1489         status = usb_interface_id(c, f);
1490         if (status < 0)
1491                 goto fail;
1492         ncm->data_id = status;
1493
1494         ncm_data_nop_intf.bInterfaceNumber = status;
1495         ncm_data_intf.bInterfaceNumber = status;
1496         ncm_union_desc.bSlaveInterface0 = status;
1497
1498         status = -ENODEV;
1499
1500         /* allocate instance-specific endpoints */
1501         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
1502         if (!ep)
1503                 goto fail;
1504         ncm->port.in_ep = ep;
1505
1506         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
1507         if (!ep)
1508                 goto fail;
1509         ncm->port.out_ep = ep;
1510
1511         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
1512         if (!ep)
1513                 goto fail;
1514         ncm->notify = ep;
1515
1516         status = -ENOMEM;
1517
1518         /* allocate notification request and buffer */
1519         ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
1520         if (!ncm->notify_req)
1521                 goto fail;
1522         ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
1523         if (!ncm->notify_req->buf)
1524                 goto fail;
1525         ncm->notify_req->context = ncm;
1526         ncm->notify_req->complete = ncm_notify_complete;
1527
1528         /*
1529          * support all relevant hardware speeds... we expect that when
1530          * hardware is dual speed, all bulk-capable endpoints work at
1531          * both speeds
1532          */
1533         hs_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1534         hs_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1535         hs_ncm_notify_desc.bEndpointAddress =
1536                 fs_ncm_notify_desc.bEndpointAddress;
1537
1538         ss_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1539         ss_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1540         ss_ncm_notify_desc.bEndpointAddress =
1541                 fs_ncm_notify_desc.bEndpointAddress;
1542
1543         status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
1544                         ncm_ss_function, ncm_ss_function);
1545         if (status)
1546                 goto fail;
1547
1548         /*
1549          * NOTE:  all that is done without knowing or caring about
1550          * the network link ... which is unavailable to this code
1551          * until we're activated via set_alt().
1552          */
1553
1554         ncm->port.open = ncm_open;
1555         ncm->port.close = ncm_close;
1556
1557         tasklet_init(&ncm->tx_tasklet, ncm_tx_tasklet, (unsigned long) ncm);
1558         hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1559         ncm->task_timer.function = ncm_tx_timeout;
1560
1561         DBG(cdev, "CDC Network: %s speed IN/%s OUT/%s NOTIFY/%s\n",
1562                         gadget_is_superspeed(c->cdev->gadget) ? "super" :
1563                         gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
1564                         ncm->port.in_ep->name, ncm->port.out_ep->name,
1565                         ncm->notify->name);
1566         return 0;
1567
1568 fail:
1569         if (ncm->notify_req) {
1570                 kfree(ncm->notify_req->buf);
1571                 usb_ep_free_request(ncm->notify, ncm->notify_req);
1572         }
1573
1574         ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1575
1576         return status;
1577 }
1578
1579 static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
1580 {
1581         return container_of(to_config_group(item), struct f_ncm_opts,
1582                             func_inst.group);
1583 }
1584
1585 /* f_ncm_item_ops */
1586 USB_ETHERNET_CONFIGFS_ITEM(ncm);
1587
1588 /* f_ncm_opts_dev_addr */
1589 USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
1590
1591 /* f_ncm_opts_host_addr */
1592 USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
1593
1594 /* f_ncm_opts_qmult */
1595 USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
1596
1597 /* f_ncm_opts_ifname */
1598 USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
1599
1600 static struct configfs_attribute *ncm_attrs[] = {
1601         &ncm_opts_attr_dev_addr,
1602         &ncm_opts_attr_host_addr,
1603         &ncm_opts_attr_qmult,
1604         &ncm_opts_attr_ifname,
1605         NULL,
1606 };
1607
1608 static struct config_item_type ncm_func_type = {
1609         .ct_item_ops    = &ncm_item_ops,
1610         .ct_attrs       = ncm_attrs,
1611         .ct_owner       = THIS_MODULE,
1612 };
1613
1614 static void ncm_free_inst(struct usb_function_instance *f)
1615 {
1616         struct f_ncm_opts *opts;
1617
1618         opts = container_of(f, struct f_ncm_opts, func_inst);
1619         if (opts->bound)
1620                 gether_cleanup(netdev_priv(opts->net));
1621         else
1622                 free_netdev(opts->net);
1623         kfree(opts);
1624 }
1625
1626 static struct usb_function_instance *ncm_alloc_inst(void)
1627 {
1628         struct f_ncm_opts *opts;
1629
1630         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1631         if (!opts)
1632                 return ERR_PTR(-ENOMEM);
1633         mutex_init(&opts->lock);
1634         opts->func_inst.free_func_inst = ncm_free_inst;
1635         opts->net = gether_setup_default();
1636         if (IS_ERR(opts->net)) {
1637                 struct net_device *net = opts->net;
1638                 kfree(opts);
1639                 return ERR_CAST(net);
1640         }
1641
1642         config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type);
1643
1644         return &opts->func_inst;
1645 }
1646
1647 static void ncm_free(struct usb_function *f)
1648 {
1649         struct f_ncm *ncm;
1650         struct f_ncm_opts *opts;
1651
1652         ncm = func_to_ncm(f);
1653         opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1654         kfree(ncm);
1655         mutex_lock(&opts->lock);
1656         opts->refcnt--;
1657         mutex_unlock(&opts->lock);
1658 }
1659
1660 static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
1661 {
1662         struct f_ncm *ncm = func_to_ncm(f);
1663
1664         DBG(c->cdev, "ncm unbind\n");
1665
1666         hrtimer_cancel(&ncm->task_timer);
1667         tasklet_kill(&ncm->tx_tasklet);
1668
1669         ncm_string_defs[0].id = 0;
1670         usb_free_all_descriptors(f);
1671
1672         if (atomic_read(&ncm->notify_count)) {
1673                 usb_ep_dequeue(ncm->notify, ncm->notify_req);
1674                 atomic_set(&ncm->notify_count, 0);
1675         }
1676
1677         kfree(ncm->notify_req->buf);
1678         usb_ep_free_request(ncm->notify, ncm->notify_req);
1679 }
1680
1681 static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
1682 {
1683         struct f_ncm            *ncm;
1684         struct f_ncm_opts       *opts;
1685         int status;
1686
1687         /* allocate and initialize one new instance */
1688         ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);
1689         if (!ncm)
1690                 return ERR_PTR(-ENOMEM);
1691
1692         opts = container_of(fi, struct f_ncm_opts, func_inst);
1693         mutex_lock(&opts->lock);
1694         opts->refcnt++;
1695
1696         /* export host's Ethernet address in CDC format */
1697         status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
1698                                       sizeof(ncm->ethaddr));
1699         if (status < 12) { /* strlen("01234567890a") */
1700                 kfree(ncm);
1701                 mutex_unlock(&opts->lock);
1702                 return ERR_PTR(-EINVAL);
1703         }
1704         ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
1705
1706         spin_lock_init(&ncm->lock);
1707         ncm_reset_values(ncm);
1708         ncm->port.ioport = netdev_priv(opts->net);
1709         mutex_unlock(&opts->lock);
1710         ncm->port.is_fixed = true;
1711         ncm->port.supports_multi_frame = true;
1712
1713         ncm->port.func.name = "cdc_network";
1714         /* descriptors are per-instance copies */
1715         ncm->port.func.bind = ncm_bind;
1716         ncm->port.func.unbind = ncm_unbind;
1717         ncm->port.func.set_alt = ncm_set_alt;
1718         ncm->port.func.get_alt = ncm_get_alt;
1719         ncm->port.func.setup = ncm_setup;
1720         ncm->port.func.disable = ncm_disable;
1721         ncm->port.func.free_func = ncm_free;
1722
1723         ncm->port.wrap = ncm_wrap_ntb;
1724         ncm->port.unwrap = ncm_unwrap_ntb;
1725
1726         return &ncm->port.func;
1727 }
1728
1729 DECLARE_USB_FUNCTION_INIT(ncm, ncm_alloc_inst, ncm_alloc);
1730 MODULE_LICENSE("GPL");
1731 MODULE_AUTHOR("Yauheni Kaliuta");