drivers/usb/gadget/function/f_ncm.c

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