drivers/usb/gadget/function/f_ncm.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * f_ncm.c -- USB CDC Network (NCM) link function driver
   4  *
   5  * Copyright (C) 2010 Nokia Corporation
   6  * Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com>
   7  *
   8  * The driver borrows from f_ecm.c which is:
   9  *
  10  * Copyright (C) 2003-2005,2008 David Brownell
  11  * Copyright (C) 2008 Nokia Corporation
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/module.h>
  17 #include <linux/device.h>
  18 #include <linux/etherdevice.h>
  19 #include <linux/crc32.h>
  20
  21 #include <linux/usb/cdc.h>
  22
  23 #include "u_ether.h"
  24 #include "u_ether_configfs.h"
  25 #include "u_ncm.h"
  26 #include "configfs.h"
  27
  28 /*
  29  * This function is a "CDC Network Control Model" (CDC NCM) Ethernet link.
  30  * NCM is intended to be used with high-speed network attachments.
  31  *
  32  * Note that NCM requires the use of "alternate settings" for its data
  33  * interface.  This means that the set_alt() method has real work to do,
  34  * and also means that a get_alt() method is required.
  35  */
  36
  37 /* to trigger crc/non-crc ndp signature */
  38
  39 #define NCM_NDP_HDR_CRC         0x01000000
  40
  41 enum ncm_notify_state {
  42         NCM_NOTIFY_NONE,                /* don't notify */
  43         NCM_NOTIFY_CONNECT,             /* issue CONNECT next */
  44         NCM_NOTIFY_SPEED,               /* issue SPEED_CHANGE next */
  45 };
  46
  47 struct f_ncm {
  48         struct gether                   port;
  49         u8                              ctrl_id, data_id;
  50
  51         char                            ethaddr[14];
  52
  53         struct usb_ep                   *notify;
  54         struct usb_request              *notify_req;
  55         u8                              notify_state;
  56         atomic_t                        notify_count;
  57         bool                            is_open;
  58
  59         const struct ndp_parser_opts    *parser_opts;
  60         bool                            is_crc;
  61         u32                             ndp_sign;
  62
  63         /*
  64          * for notification, it is accessed from both
  65          * callback and ethernet open/close
  66          */
  67         spinlock_t                      lock;
  68
  69         struct net_device               *netdev;
  70
  71         /* For multi-frame NDP TX */
  72         struct sk_buff                  *skb_tx_data;
  73         struct sk_buff                  *skb_tx_ndp;
  74         u16                             ndp_dgram_count;
  75         struct hrtimer                  task_timer;
  76 };
  77
  78 static inline struct f_ncm *func_to_ncm(struct usb_function *f)
  79 {
  80         return container_of(f, struct f_ncm, port.func);
  81 }
  82
  83 /*-------------------------------------------------------------------------*/
  84
  85 /*
  86  * We cannot group frames so use just the minimal size which ok to put
  87  * one max-size ethernet frame.
  88  * If the host can group frames, allow it to do that, 16K is selected,
  89  * because it's used by default by the current linux host driver
  90  */
  91 #define NTB_DEFAULT_IN_SIZE     16384
  92 #define NTB_OUT_SIZE            16384
  93
  94 /* Allocation for storing the NDP, 32 should suffice for a
  95  * 16k packet. This allows a maximum of 32 * 507 Byte packets to
  96  * be transmitted in a single 16kB skb, though when sending full size
  97  * packets this limit will be plenty.
  98  * Smaller packets are not likely to be trying to maximize the
  99  * throughput and will be mstly sending smaller infrequent frames.
 100  */
 101 #define TX_MAX_NUM_DPE          32
 102
 103 /* Delay for the transmit to wait before sending an unfilled NTB frame. */
 104 #define TX_TIMEOUT_NSECS        300000
 105
 106 #define FORMATS_SUPPORTED       (USB_CDC_NCM_NTB16_SUPPORTED |  \
 107                                  USB_CDC_NCM_NTB32_SUPPORTED)
 108
 109 static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
 110         .wLength = cpu_to_le16(sizeof(ntb_parameters)),
 111         .bmNtbFormatsSupported = cpu_to_le16(FORMATS_SUPPORTED),
 112         .dwNtbInMaxSize = cpu_to_le32(NTB_DEFAULT_IN_SIZE),
 113         .wNdpInDivisor = cpu_to_le16(4),
 114         .wNdpInPayloadRemainder = cpu_to_le16(0),
 115         .wNdpInAlignment = cpu_to_le16(4),
 116
 117         .dwNtbOutMaxSize = cpu_to_le32(NTB_OUT_SIZE),
 118         .wNdpOutDivisor = cpu_to_le16(4),
 119         .wNdpOutPayloadRemainder = cpu_to_le16(0),
 120         .wNdpOutAlignment = cpu_to_le16(4),
 121 };
 122
 123 /*
 124  * Use wMaxPacketSize big enough to fit CDC_NOTIFY_SPEED_CHANGE in one
 125  * packet, to simplify cancellation; and a big transfer interval, to
 126  * waste less bandwidth.
 127  */
 128
 129 #define NCM_STATUS_INTERVAL_MS          32
 130 #define NCM_STATUS_BYTECOUNT            16      /* 8 byte header + data */
 131
 132 static struct usb_interface_assoc_descriptor ncm_iad_desc = {
 133         .bLength =              sizeof ncm_iad_desc,
 134         .bDescriptorType =      USB_DT_INTERFACE_ASSOCIATION,
 135
 136         /* .bFirstInterface =   DYNAMIC, */
 137         .bInterfaceCount =      2,      /* control + data */
 138         .bFunctionClass =       USB_CLASS_COMM,
 139         .bFunctionSubClass =    USB_CDC_SUBCLASS_NCM,
 140         .bFunctionProtocol =    USB_CDC_PROTO_NONE,
 141         /* .iFunction =         DYNAMIC */
 142 };
 143
 144 /* interface descriptor: */
 145
 146 static struct usb_interface_descriptor ncm_control_intf = {
 147         .bLength =              sizeof ncm_control_intf,
 148         .bDescriptorType =      USB_DT_INTERFACE,
 149
 150         /* .bInterfaceNumber = DYNAMIC */
 151         .bNumEndpoints =        1,
 152         .bInterfaceClass =      USB_CLASS_COMM,
 153         .bInterfaceSubClass =   USB_CDC_SUBCLASS_NCM,
 154         .bInterfaceProtocol =   USB_CDC_PROTO_NONE,
 155         /* .iInterface = DYNAMIC */
 156 };
 157
 158 static struct usb_cdc_header_desc ncm_header_desc = {
 159         .bLength =              sizeof ncm_header_desc,
 160         .bDescriptorType =      USB_DT_CS_INTERFACE,
 161         .bDescriptorSubType =   USB_CDC_HEADER_TYPE,
 162
 163         .bcdCDC =               cpu_to_le16(0x0110),
 164 };
 165
 166 static struct usb_cdc_union_desc ncm_union_desc = {
 167         .bLength =              sizeof(ncm_union_desc),
 168         .bDescriptorType =      USB_DT_CS_INTERFACE,
 169         .bDescriptorSubType =   USB_CDC_UNION_TYPE,
 170         /* .bMasterInterface0 = DYNAMIC */
 171         /* .bSlaveInterface0 =  DYNAMIC */
 172 };
 173
 174 static struct usb_cdc_ether_desc ecm_desc = {
 175         .bLength =              sizeof ecm_desc,
 176         .bDescriptorType =      USB_DT_CS_INTERFACE,
 177         .bDescriptorSubType =   USB_CDC_ETHERNET_TYPE,
 178
 179         /* this descriptor actually adds value, surprise! */
 180         /* .iMACAddress = DYNAMIC */
 181         .bmEthernetStatistics = cpu_to_le32(0), /* no statistics */
 182         .wMaxSegmentSize =      cpu_to_le16(ETH_FRAME_LEN),
 183         .wNumberMCFilters =     cpu_to_le16(0),
 184         .bNumberPowerFilters =  0,
 185 };
 186
 187 #define NCAPS   (USB_CDC_NCM_NCAP_ETH_FILTER | USB_CDC_NCM_NCAP_CRC_MODE)
 188
 189 static struct usb_cdc_ncm_desc ncm_desc = {
 190         .bLength =              sizeof ncm_desc,
 191         .bDescriptorType =      USB_DT_CS_INTERFACE,
 192         .bDescriptorSubType =   USB_CDC_NCM_TYPE,
 193
 194         .bcdNcmVersion =        cpu_to_le16(0x0100),
 195         /* can process SetEthernetPacketFilter */
 196         .bmNetworkCapabilities = NCAPS,
 197 };
 198
 199 /* the default data interface has no endpoints ... */
 200
 201 static struct usb_interface_descriptor ncm_data_nop_intf = {
 202         .bLength =              sizeof ncm_data_nop_intf,
 203         .bDescriptorType =      USB_DT_INTERFACE,
 204
 205         .bInterfaceNumber =     1,
 206         .bAlternateSetting =    0,
 207         .bNumEndpoints =        0,
 208         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 209         .bInterfaceSubClass =   0,
 210         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 211         /* .iInterface = DYNAMIC */
 212 };
 213
 214 /* ... but the "real" data interface has two bulk endpoints */
 215
 216 static struct usb_interface_descriptor ncm_data_intf = {
 217         .bLength =              sizeof ncm_data_intf,
 218         .bDescriptorType =      USB_DT_INTERFACE,
 219
 220         .bInterfaceNumber =     1,
 221         .bAlternateSetting =    1,
 222         .bNumEndpoints =        2,
 223         .bInterfaceClass =      USB_CLASS_CDC_DATA,
 224         .bInterfaceSubClass =   0,
 225         .bInterfaceProtocol =   USB_CDC_NCM_PROTO_NTB,
 226         /* .iInterface = DYNAMIC */
 227 };
 228
 229 /* full speed support: */
 230
 231 static struct usb_endpoint_descriptor fs_ncm_notify_desc = {
 232         .bLength =              USB_DT_ENDPOINT_SIZE,
 233         .bDescriptorType =      USB_DT_ENDPOINT,
 234
 235         .bEndpointAddress =     USB_DIR_IN,
 236         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 237         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 238         .bInterval =            NCM_STATUS_INTERVAL_MS,
 239 };
 240
 241 static struct usb_endpoint_descriptor fs_ncm_in_desc = {
 242         .bLength =              USB_DT_ENDPOINT_SIZE,
 243         .bDescriptorType =      USB_DT_ENDPOINT,
 244
 245         .bEndpointAddress =     USB_DIR_IN,
 246         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 247 };
 248
 249 static struct usb_endpoint_descriptor fs_ncm_out_desc = {
 250         .bLength =              USB_DT_ENDPOINT_SIZE,
 251         .bDescriptorType =      USB_DT_ENDPOINT,
 252
 253         .bEndpointAddress =     USB_DIR_OUT,
 254         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 255 };
 256
 257 static struct usb_descriptor_header *ncm_fs_function[] = {
 258         (struct usb_descriptor_header *) &ncm_iad_desc,
 259         /* CDC NCM control descriptors */
 260         (struct usb_descriptor_header *) &ncm_control_intf,
 261         (struct usb_descriptor_header *) &ncm_header_desc,
 262         (struct usb_descriptor_header *) &ncm_union_desc,
 263         (struct usb_descriptor_header *) &ecm_desc,
 264         (struct usb_descriptor_header *) &ncm_desc,
 265         (struct usb_descriptor_header *) &fs_ncm_notify_desc,
 266         /* data interface, altsettings 0 and 1 */
 267         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 268         (struct usb_descriptor_header *) &ncm_data_intf,
 269         (struct usb_descriptor_header *) &fs_ncm_in_desc,
 270         (struct usb_descriptor_header *) &fs_ncm_out_desc,
 271         NULL,
 272 };
 273
 274 /* high speed support: */
 275
 276 static struct usb_endpoint_descriptor hs_ncm_notify_desc = {
 277         .bLength =              USB_DT_ENDPOINT_SIZE,
 278         .bDescriptorType =      USB_DT_ENDPOINT,
 279
 280         .bEndpointAddress =     USB_DIR_IN,
 281         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 282         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 283         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS),
 284 };
 285 static struct usb_endpoint_descriptor hs_ncm_in_desc = {
 286         .bLength =              USB_DT_ENDPOINT_SIZE,
 287         .bDescriptorType =      USB_DT_ENDPOINT,
 288
 289         .bEndpointAddress =     USB_DIR_IN,
 290         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 291         .wMaxPacketSize =       cpu_to_le16(512),
 292 };
 293
 294 static struct usb_endpoint_descriptor hs_ncm_out_desc = {
 295         .bLength =              USB_DT_ENDPOINT_SIZE,
 296         .bDescriptorType =      USB_DT_ENDPOINT,
 297
 298         .bEndpointAddress =     USB_DIR_OUT,
 299         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 300         .wMaxPacketSize =       cpu_to_le16(512),
 301 };
 302
 303 static struct usb_descriptor_header *ncm_hs_function[] = {
 304         (struct usb_descriptor_header *) &ncm_iad_desc,
 305         /* CDC NCM control descriptors */
 306         (struct usb_descriptor_header *) &ncm_control_intf,
 307         (struct usb_descriptor_header *) &ncm_header_desc,
 308         (struct usb_descriptor_header *) &ncm_union_desc,
 309         (struct usb_descriptor_header *) &ecm_desc,
 310         (struct usb_descriptor_header *) &ncm_desc,
 311         (struct usb_descriptor_header *) &hs_ncm_notify_desc,
 312         /* data interface, altsettings 0 and 1 */
 313         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 314         (struct usb_descriptor_header *) &ncm_data_intf,
 315         (struct usb_descriptor_header *) &hs_ncm_in_desc,
 316         (struct usb_descriptor_header *) &hs_ncm_out_desc,
 317         NULL,
 318 };
 319
 320
 321 /* super speed support: */
 322
 323 static struct usb_endpoint_descriptor ss_ncm_notify_desc = {
 324         .bLength =              USB_DT_ENDPOINT_SIZE,
 325         .bDescriptorType =      USB_DT_ENDPOINT,
 326
 327         .bEndpointAddress =     USB_DIR_IN,
 328         .bmAttributes =         USB_ENDPOINT_XFER_INT,
 329         .wMaxPacketSize =       cpu_to_le16(NCM_STATUS_BYTECOUNT),
 330         .bInterval =            USB_MS_TO_HS_INTERVAL(NCM_STATUS_INTERVAL_MS)
 331 };
 332
 333 static struct usb_ss_ep_comp_descriptor ss_ncm_notify_comp_desc = {
 334         .bLength =              sizeof(ss_ncm_notify_comp_desc),
 335         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 336
 337         /* the following 3 values can be tweaked if necessary */
 338         /* .bMaxBurst =         0, */
 339         /* .bmAttributes =      0, */
 340         .wBytesPerInterval =    cpu_to_le16(NCM_STATUS_BYTECOUNT),
 341 };
 342
 343 static struct usb_endpoint_descriptor ss_ncm_in_desc = {
 344         .bLength =              USB_DT_ENDPOINT_SIZE,
 345         .bDescriptorType =      USB_DT_ENDPOINT,
 346
 347         .bEndpointAddress =     USB_DIR_IN,
 348         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 349         .wMaxPacketSize =       cpu_to_le16(1024),
 350 };
 351
 352 static struct usb_endpoint_descriptor ss_ncm_out_desc = {
 353         .bLength =              USB_DT_ENDPOINT_SIZE,
 354         .bDescriptorType =      USB_DT_ENDPOINT,
 355
 356         .bEndpointAddress =     USB_DIR_OUT,
 357         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 358         .wMaxPacketSize =       cpu_to_le16(1024),
 359 };
 360
 361 static struct usb_ss_ep_comp_descriptor ss_ncm_bulk_comp_desc = {
 362         .bLength =              sizeof(ss_ncm_bulk_comp_desc),
 363         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 364
 365         /* the following 2 values can be tweaked if necessary */
 366         .bMaxBurst =            15,
 367         /* .bmAttributes =      0, */
 368 };
 369
 370 static struct usb_descriptor_header *ncm_ss_function[] = {
 371         (struct usb_descriptor_header *) &ncm_iad_desc,
 372         /* CDC NCM control descriptors */
 373         (struct usb_descriptor_header *) &ncm_control_intf,
 374         (struct usb_descriptor_header *) &ncm_header_desc,
 375         (struct usb_descriptor_header *) &ncm_union_desc,
 376         (struct usb_descriptor_header *) &ecm_desc,
 377         (struct usb_descriptor_header *) &ncm_desc,
 378         (struct usb_descriptor_header *) &ss_ncm_notify_desc,
 379         (struct usb_descriptor_header *) &ss_ncm_notify_comp_desc,
 380         /* data interface, altsettings 0 and 1 */
 381         (struct usb_descriptor_header *) &ncm_data_nop_intf,
 382         (struct usb_descriptor_header *) &ncm_data_intf,
 383         (struct usb_descriptor_header *) &ss_ncm_in_desc,
 384         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 385         (struct usb_descriptor_header *) &ss_ncm_out_desc,
 386         (struct usb_descriptor_header *) &ss_ncm_bulk_comp_desc,
 387         NULL,
 388 };
 389
 390 /* string descriptors: */
 391
 392 #define STRING_CTRL_IDX 0
 393 #define STRING_MAC_IDX  1
 394 #define STRING_DATA_IDX 2
 395 #define STRING_IAD_IDX  3
 396
 397 static struct usb_string ncm_string_defs[] = {
 398         [STRING_CTRL_IDX].s = "CDC Network Control Model (NCM)",
 399         [STRING_MAC_IDX].s = "",
 400         [STRING_DATA_IDX].s = "CDC Network Data",
 401         [STRING_IAD_IDX].s = "CDC NCM",
 402         {  } /* end of list */
 403 };
 404
 405 static struct usb_gadget_strings ncm_string_table = {
 406         .language =             0x0409, /* en-us */
 407         .strings =              ncm_string_defs,
 408 };
 409
 410 static struct usb_gadget_strings *ncm_strings[] = {
 411         &ncm_string_table,
 412         NULL,
 413 };
 414
 415 /*
 416  * Here are options for NCM Datagram Pointer table (NDP) parser.
 417  * There are 2 different formats: NDP16 and NDP32 in the spec (ch. 3),
 418  * in NDP16 offsets and sizes fields are 1 16bit word wide,
 419  * in NDP32 -- 2 16bit words wide. Also signatures are different.
 420  * To make the parser code the same, put the differences in the structure,
 421  * and switch pointers to the structures when the format is changed.
 422  */
 423
 424 struct ndp_parser_opts {
 425         u32             nth_sign;
 426         u32             ndp_sign;
 427         unsigned        nth_size;
 428         unsigned        ndp_size;
 429         unsigned        dpe_size;
 430         unsigned        ndplen_align;
 431         /* sizes in u16 units */
 432         unsigned        dgram_item_len; /* index or length */
 433         unsigned        block_length;
 434         unsigned        ndp_index;
 435         unsigned        reserved1;
 436         unsigned        reserved2;
 437         unsigned        next_ndp_index;
 438 };
 439
 440 static const struct ndp_parser_opts ndp16_opts = {
 441         .nth_sign = USB_CDC_NCM_NTH16_SIGN,
 442         .ndp_sign = USB_CDC_NCM_NDP16_NOCRC_SIGN,
 443         .nth_size = sizeof(struct usb_cdc_ncm_nth16),
 444         .ndp_size = sizeof(struct usb_cdc_ncm_ndp16),
 445         .dpe_size = sizeof(struct usb_cdc_ncm_dpe16),
 446         .ndplen_align = 4,
 447         .dgram_item_len = 1,
 448         .block_length = 1,
 449         .ndp_index = 1,
 450         .reserved1 = 0,
 451         .reserved2 = 0,
 452         .next_ndp_index = 1,
 453 };
 454
 455 static const struct ndp_parser_opts ndp32_opts = {
 456         .nth_sign = USB_CDC_NCM_NTH32_SIGN,
 457         .ndp_sign = USB_CDC_NCM_NDP32_NOCRC_SIGN,
 458         .nth_size = sizeof(struct usb_cdc_ncm_nth32),
 459         .ndp_size = sizeof(struct usb_cdc_ncm_ndp32),
 460         .dpe_size = sizeof(struct usb_cdc_ncm_dpe32),
 461         .ndplen_align = 8,
 462         .dgram_item_len = 2,
 463         .block_length = 2,
 464         .ndp_index = 2,
 465         .reserved1 = 1,
 466         .reserved2 = 2,
 467         .next_ndp_index = 2,
 468 };
 469
 470 static inline void put_ncm(__le16 **p, unsigned size, unsigned val)
 471 {
 472         switch (size) {
 473         case 1:
 474                 put_unaligned_le16((u16)val, *p);
 475                 break;
 476         case 2:
 477                 put_unaligned_le32((u32)val, *p);
 478
 479                 break;
 480         default:
 481                 BUG();
 482         }
 483
 484         *p += size;
 485 }
 486
 487 static inline unsigned get_ncm(__le16 **p, unsigned size)
 488 {
 489         unsigned tmp;
 490
 491         switch (size) {
 492         case 1:
 493                 tmp = get_unaligned_le16(*p);
 494                 break;
 495         case 2:
 496                 tmp = get_unaligned_le32(*p);
 497                 break;
 498         default:
 499                 BUG();
 500         }
 501
 502         *p += size;
 503         return tmp;
 504 }
 505
 506 /*-------------------------------------------------------------------------*/
 507
 508 static inline void ncm_reset_values(struct f_ncm *ncm)
 509 {
 510         ncm->parser_opts = &ndp16_opts;
 511         ncm->is_crc = false;
 512         ncm->ndp_sign = ncm->parser_opts->ndp_sign;
 513         ncm->port.cdc_filter = DEFAULT_FILTER;
 514
 515         /* doesn't make sense for ncm, fixed size used */
 516         ncm->port.header_len = 0;
 517
 518         ncm->port.fixed_out_len = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
 519         ncm->port.fixed_in_len = NTB_DEFAULT_IN_SIZE;
 520 }
 521
 522 /*
 523  * Context: ncm->lock held
 524  */
 525 static void ncm_do_notify(struct f_ncm *ncm)
 526 {
 527         struct usb_request              *req = ncm->notify_req;
 528         struct usb_cdc_notification     *event;
 529         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 530         __le32                          *data;
 531         int                             status;
 532
 533         /* notification already in flight? */
 534         if (atomic_read(&ncm->notify_count))
 535                 return;
 536
 537         event = req->buf;
 538         switch (ncm->notify_state) {
 539         case NCM_NOTIFY_NONE:
 540                 return;
 541
 542         case NCM_NOTIFY_CONNECT:
 543                 event->bNotificationType = USB_CDC_NOTIFY_NETWORK_CONNECTION;
 544                 if (ncm->is_open)
 545                         event->wValue = cpu_to_le16(1);
 546                 else
 547                         event->wValue = cpu_to_le16(0);
 548                 event->wLength = 0;
 549                 req->length = sizeof *event;
 550
 551                 DBG(cdev, "notify connect %s\n",
 552                                 ncm->is_open ? "true" : "false");
 553                 ncm->notify_state = NCM_NOTIFY_NONE;
 554                 break;
 555
 556         case NCM_NOTIFY_SPEED:
 557                 event->bNotificationType = USB_CDC_NOTIFY_SPEED_CHANGE;
 558                 event->wValue = cpu_to_le16(0);
 559                 event->wLength = cpu_to_le16(8);
 560                 req->length = NCM_STATUS_BYTECOUNT;
 561
 562                 /* SPEED_CHANGE data is up/down speeds in bits/sec */
 563                 data = req->buf + sizeof *event;
 564                 data[0] = cpu_to_le32(gether_bitrate(cdev->gadget));
 565                 data[1] = data[0];
 566
 567                 DBG(cdev, "notify speed %u\n", gether_bitrate(cdev->gadget));
 568                 ncm->notify_state = NCM_NOTIFY_CONNECT;
 569                 break;
 570         }
 571         event->bmRequestType = 0xA1;
 572         event->wIndex = cpu_to_le16(ncm->ctrl_id);
 573
 574         atomic_inc(&ncm->notify_count);
 575
 576         /*
 577          * In double buffering if there is a space in FIFO,
 578          * completion callback can be called right after the call,
 579          * so unlocking
 580          */
 581         spin_unlock(&ncm->lock);
 582         status = usb_ep_queue(ncm->notify, req, GFP_ATOMIC);
 583         spin_lock(&ncm->lock);
 584         if (status < 0) {
 585                 atomic_dec(&ncm->notify_count);
 586                 DBG(cdev, "notify --> %d\n", status);
 587         }
 588 }
 589
 590 /*
 591  * Context: ncm->lock held
 592  */
 593 static void ncm_notify(struct f_ncm *ncm)
 594 {
 595         /*
 596          * NOTE on most versions of Linux, host side cdc-ethernet
 597          * won't listen for notifications until its netdevice opens.
 598          * The first notification then sits in the FIFO for a long
 599          * time, and the second one is queued.
 600          *
 601          * If ncm_notify() is called before the second (CONNECT)
 602          * notification is sent, then it will reset to send the SPEED
 603          * notificaion again (and again, and again), but it's not a problem
 604          */
 605         ncm->notify_state = NCM_NOTIFY_SPEED;
 606         ncm_do_notify(ncm);
 607 }
 608
 609 static void ncm_notify_complete(struct usb_ep *ep, struct usb_request *req)
 610 {
 611         struct f_ncm                    *ncm = req->context;
 612         struct usb_composite_dev        *cdev = ncm->port.func.config->cdev;
 613         struct usb_cdc_notification     *event = req->buf;
 614
 615         spin_lock(&ncm->lock);
 616         switch (req->status) {
 617         case 0:
 618                 VDBG(cdev, "Notification %02x sent\n",
 619                      event->bNotificationType);
 620                 atomic_dec(&ncm->notify_count);
 621                 break;
 622         case -ECONNRESET:
 623         case -ESHUTDOWN:
 624                 atomic_set(&ncm->notify_count, 0);
 625                 ncm->notify_state = NCM_NOTIFY_NONE;
 626                 break;
 627         default:
 628                 DBG(cdev, "event %02x --> %d\n",
 629                         event->bNotificationType, req->status);
 630                 atomic_dec(&ncm->notify_count);
 631                 break;
 632         }
 633         ncm_do_notify(ncm);
 634         spin_unlock(&ncm->lock);
 635 }
 636
 637 static void ncm_ep0out_complete(struct usb_ep *ep, struct usb_request *req)
 638 {
 639         /* now for SET_NTB_INPUT_SIZE only */
 640         unsigned                in_size;
 641         struct usb_function     *f = req->context;
 642         struct f_ncm            *ncm = func_to_ncm(f);
 643         struct usb_composite_dev *cdev = f->config->cdev;
 644
 645         req->context = NULL;
 646         if (req->status || req->actual != req->length) {
 647                 DBG(cdev, "Bad control-OUT transfer\n");
 648                 goto invalid;
 649         }
 650
 651         in_size = get_unaligned_le32(req->buf);
 652         if (in_size < USB_CDC_NCM_NTB_MIN_IN_SIZE ||
 653             in_size > le32_to_cpu(ntb_parameters.dwNtbInMaxSize)) {
 654                 DBG(cdev, "Got wrong INPUT SIZE (%d) from host\n", in_size);
 655                 goto invalid;
 656         }
 657
 658         ncm->port.fixed_in_len = in_size;
 659         VDBG(cdev, "Set NTB INPUT SIZE %d\n", in_size);
 660         return;
 661
 662 invalid:
 663         usb_ep_set_halt(ep);
 664         return;
 665 }
 666
 667 static int ncm_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 668 {
 669         struct f_ncm            *ncm = func_to_ncm(f);
 670         struct usb_composite_dev *cdev = f->config->cdev;
 671         struct usb_request      *req = cdev->req;
 672         int                     value = -EOPNOTSUPP;
 673         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 674         u16                     w_value = le16_to_cpu(ctrl->wValue);
 675         u16                     w_length = le16_to_cpu(ctrl->wLength);
 676
 677         /*
 678          * composite driver infrastructure handles everything except
 679          * CDC class messages; interface activation uses set_alt().
 680          */
 681         switch ((ctrl->bRequestType << 8) | ctrl->bRequest) {
 682         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 683                         | USB_CDC_SET_ETHERNET_PACKET_FILTER:
 684                 /*
 685                  * see 6.2.30: no data, wIndex = interface,
 686                  * wValue = packet filter bitmap
 687                  */
 688                 if (w_length != 0 || w_index != ncm->ctrl_id)
 689                         goto invalid;
 690                 DBG(cdev, "packet filter %02x\n", w_value);
 691                 /*
 692                  * REVISIT locking of cdc_filter.  This assumes the UDC
 693                  * driver won't have a concurrent packet TX irq running on
 694                  * another CPU; or that if it does, this write is atomic...
 695                  */
 696                 ncm->port.cdc_filter = w_value;
 697                 value = 0;
 698                 break;
 699         /*
 700          * and optionally:
 701          * case USB_CDC_SEND_ENCAPSULATED_COMMAND:
 702          * case USB_CDC_GET_ENCAPSULATED_RESPONSE:
 703          * case USB_CDC_SET_ETHERNET_MULTICAST_FILTERS:
 704          * case USB_CDC_SET_ETHERNET_PM_PATTERN_FILTER:
 705          * case USB_CDC_GET_ETHERNET_PM_PATTERN_FILTER:
 706          * case USB_CDC_GET_ETHERNET_STATISTIC:
 707          */
 708
 709         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 710                 | USB_CDC_GET_NTB_PARAMETERS:
 711
 712                 if (w_length == 0 || w_value != 0 || w_index != ncm->ctrl_id)
 713                         goto invalid;
 714                 value = w_length > sizeof ntb_parameters ?
 715                         sizeof ntb_parameters : w_length;
 716                 memcpy(req->buf, &ntb_parameters, value);
 717                 VDBG(cdev, "Host asked NTB parameters\n");
 718                 break;
 719
 720         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 721                 | USB_CDC_GET_NTB_INPUT_SIZE:
 722
 723                 if (w_length < 4 || w_value != 0 || w_index != ncm->ctrl_id)
 724                         goto invalid;
 725                 put_unaligned_le32(ncm->port.fixed_in_len, req->buf);
 726                 value = 4;
 727                 VDBG(cdev, "Host asked INPUT SIZE, sending %d\n",
 728                      ncm->port.fixed_in_len);
 729                 break;
 730
 731         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 732                 | USB_CDC_SET_NTB_INPUT_SIZE:
 733         {
 734                 if (w_length != 4 || w_value != 0 || w_index != ncm->ctrl_id)
 735                         goto invalid;
 736                 req->complete = ncm_ep0out_complete;
 737                 req->length = w_length;
 738                 req->context = f;
 739
 740                 value = req->length;
 741                 break;
 742         }
 743
 744         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 745                 | USB_CDC_GET_NTB_FORMAT:
 746         {
 747                 uint16_t format;
 748
 749                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 750                         goto invalid;
 751                 format = (ncm->parser_opts == &ndp16_opts) ? 0x0000 : 0x0001;
 752                 put_unaligned_le16(format, req->buf);
 753                 value = 2;
 754                 VDBG(cdev, "Host asked NTB FORMAT, sending %d\n", format);
 755                 break;
 756         }
 757
 758         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 759                 | USB_CDC_SET_NTB_FORMAT:
 760         {
 761                 if (w_length != 0 || w_index != ncm->ctrl_id)
 762                         goto invalid;
 763                 switch (w_value) {
 764                 case 0x0000:
 765                         ncm->parser_opts = &ndp16_opts;
 766                         DBG(cdev, "NCM16 selected\n");
 767                         break;
 768                 case 0x0001:
 769                         ncm->parser_opts = &ndp32_opts;
 770                         DBG(cdev, "NCM32 selected\n");
 771                         break;
 772                 default:
 773                         goto invalid;
 774                 }
 775                 value = 0;
 776                 break;
 777         }
 778         case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 779                 | USB_CDC_GET_CRC_MODE:
 780         {
 781                 uint16_t is_crc;
 782
 783                 if (w_length < 2 || w_value != 0 || w_index != ncm->ctrl_id)
 784                         goto invalid;
 785                 is_crc = ncm->is_crc ? 0x0001 : 0x0000;
 786                 put_unaligned_le16(is_crc, req->buf);
 787                 value = 2;
 788                 VDBG(cdev, "Host asked CRC MODE, sending %d\n", is_crc);
 789                 break;
 790         }
 791
 792         case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8)
 793                 | USB_CDC_SET_CRC_MODE:
 794         {
 795                 if (w_length != 0 || w_index != ncm->ctrl_id)
 796                         goto invalid;
 797                 switch (w_value) {
 798                 case 0x0000:
 799                         ncm->is_crc = false;
 800                         DBG(cdev, "non-CRC mode selected\n");
 801                         break;
 802                 case 0x0001:
 803                         ncm->is_crc = true;
 804                         DBG(cdev, "CRC mode selected\n");
 805                         break;
 806                 default:
 807                         goto invalid;
 808                 }
 809                 value = 0;
 810                 break;
 811         }
 812
 813         /* and disabled in ncm descriptor: */
 814         /* case USB_CDC_GET_NET_ADDRESS: */
 815         /* case USB_CDC_SET_NET_ADDRESS: */
 816         /* case USB_CDC_GET_MAX_DATAGRAM_SIZE: */
 817         /* case USB_CDC_SET_MAX_DATAGRAM_SIZE: */
 818
 819         default:
 820 invalid:
 821                 DBG(cdev, "invalid control req%02x.%02x v%04x i%04x l%d\n",
 822                         ctrl->bRequestType, ctrl->bRequest,
 823                         w_value, w_index, w_length);
 824         }
 825         ncm->ndp_sign = ncm->parser_opts->ndp_sign |
 826                 (ncm->is_crc ? NCM_NDP_HDR_CRC : 0);
 827
 828         /* respond with data transfer or status phase? */
 829         if (value >= 0) {
 830                 DBG(cdev, "ncm req%02x.%02x v%04x i%04x l%d\n",
 831                         ctrl->bRequestType, ctrl->bRequest,
 832                         w_value, w_index, w_length);
 833                 req->zero = 0;
 834                 req->length = value;
 835                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 836                 if (value < 0)
 837                         ERROR(cdev, "ncm req %02x.%02x response err %d\n",
 838                                         ctrl->bRequestType, ctrl->bRequest,
 839                                         value);
 840         }
 841
 842         /* device either stalls (value < 0) or reports success */
 843         return value;
 844 }
 845
 846
 847 static int ncm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 848 {
 849         struct f_ncm            *ncm = func_to_ncm(f);
 850         struct usb_composite_dev *cdev = f->config->cdev;
 851
 852         /* Control interface has only altsetting 0 */
 853         if (intf == ncm->ctrl_id) {
 854                 if (alt != 0)
 855                         goto fail;
 856
 857                 DBG(cdev, "reset ncm control %d\n", intf);
 858                 usb_ep_disable(ncm->notify);
 859
 860                 if (!(ncm->notify->desc)) {
 861                         DBG(cdev, "init ncm ctrl %d\n", intf);
 862                         if (config_ep_by_speed(cdev->gadget, f, ncm->notify))
 863                                 goto fail;
 864                 }
 865                 usb_ep_enable(ncm->notify);
 866
 867         /* Data interface has two altsettings, 0 and 1 */
 868         } else if (intf == ncm->data_id) {
 869                 if (alt > 1)
 870                         goto fail;
 871
 872                 if (ncm->port.in_ep->enabled) {
 873                         DBG(cdev, "reset ncm\n");
 874                         ncm->netdev = NULL;
 875                         gether_disconnect(&ncm->port);
 876                         ncm_reset_values(ncm);
 877                 }
 878
 879                 /*
 880                  * CDC Network only sends data in non-default altsettings.
 881                  * Changing altsettings resets filters, statistics, etc.
 882                  */
 883                 if (alt == 1) {
 884                         struct net_device       *net;
 885
 886                         if (!ncm->port.in_ep->desc ||
 887                             !ncm->port.out_ep->desc) {
 888                                 DBG(cdev, "init ncm\n");
 889                                 if (config_ep_by_speed(cdev->gadget, f,
 890                                                        ncm->port.in_ep) ||
 891                                     config_ep_by_speed(cdev->gadget, f,
 892                                                        ncm->port.out_ep)) {
 893                                         ncm->port.in_ep->desc = NULL;
 894                                         ncm->port.out_ep->desc = NULL;
 895                                         goto fail;
 896                                 }
 897                         }
 898
 899                         /* TODO */
 900                         /* Enable zlps by default for NCM conformance;
 901                          * override for musb_hdrc (avoids txdma ovhead)
 902                          */
 903                         ncm->port.is_zlp_ok =
 904                                 gadget_is_zlp_supported(cdev->gadget);
 905                         ncm->port.cdc_filter = DEFAULT_FILTER;
 906                         DBG(cdev, "activate ncm\n");
 907                         net = gether_connect(&ncm->port);
 908                         if (IS_ERR(net))
 909                                 return PTR_ERR(net);
 910                         ncm->netdev = net;
 911                 }
 912
 913                 spin_lock(&ncm->lock);
 914                 ncm_notify(ncm);
 915                 spin_unlock(&ncm->lock);
 916         } else
 917                 goto fail;
 918
 919         return 0;
 920 fail:
 921         return -EINVAL;
 922 }
 923
 924 /*
 925  * Because the data interface supports multiple altsettings,
 926  * this NCM function *MUST* implement a get_alt() method.
 927  */
 928 static int ncm_get_alt(struct usb_function *f, unsigned intf)
 929 {
 930         struct f_ncm            *ncm = func_to_ncm(f);
 931
 932         if (intf == ncm->ctrl_id)
 933                 return 0;
 934         return ncm->port.in_ep->enabled ? 1 : 0;
 935 }
 936
 937 static struct sk_buff *package_for_tx(struct f_ncm *ncm)
 938 {
 939         __le16          *ntb_iter;
 940         struct sk_buff  *skb2 = NULL;
 941         unsigned        ndp_pad;
 942         unsigned        ndp_index;
 943         unsigned        new_len;
 944
 945         const struct ndp_parser_opts *opts = ncm->parser_opts;
 946         const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
 947         const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
 948
 949         /* Stop the timer */
 950         hrtimer_try_to_cancel(&ncm->task_timer);
 951
 952         ndp_pad = ALIGN(ncm->skb_tx_data->len, ndp_align) -
 953                         ncm->skb_tx_data->len;
 954         ndp_index = ncm->skb_tx_data->len + ndp_pad;
 955         new_len = ndp_index + dgram_idx_len + ncm->skb_tx_ndp->len;
 956
 957         /* Set the final BlockLength and wNdpIndex */
 958         ntb_iter = (void *) ncm->skb_tx_data->data;
 959         /* Increment pointer to BlockLength */
 960         ntb_iter += 2 + 1 + 1;
 961         put_ncm(&ntb_iter, opts->block_length, new_len);
 962         put_ncm(&ntb_iter, opts->ndp_index, ndp_index);
 963
 964         /* Set the final NDP wLength */
 965         new_len = opts->ndp_size +
 966                         (ncm->ndp_dgram_count * dgram_idx_len);
 967         ncm->ndp_dgram_count = 0;
 968         /* Increment from start to wLength */
 969         ntb_iter = (void *) ncm->skb_tx_ndp->data;
 970         ntb_iter += 2;
 971         put_unaligned_le16(new_len, ntb_iter);
 972
 973         /* Merge the skbs */
 974         swap(skb2, ncm->skb_tx_data);
 975         if (ncm->skb_tx_data) {
 976                 dev_consume_skb_any(ncm->skb_tx_data);
 977                 ncm->skb_tx_data = NULL;
 978         }
 979
 980         /* Insert NDP alignment. */
 981         skb_put_zero(skb2, ndp_pad);
 982
 983         /* Copy NTB across. */
 984         skb_put_data(skb2, ncm->skb_tx_ndp->data, ncm->skb_tx_ndp->len);
 985         dev_consume_skb_any(ncm->skb_tx_ndp);
 986         ncm->skb_tx_ndp = NULL;
 987
 988         /* Insert zero'd datagram. */
 989         skb_put_zero(skb2, dgram_idx_len);
 990
 991         return skb2;
 992 }
 993
 994 static struct sk_buff *ncm_wrap_ntb(struct gether *port,
 995                                     struct sk_buff *skb)
 996 {
 997         struct f_ncm    *ncm = func_to_ncm(&port->func);
 998         struct sk_buff  *skb2 = NULL;
 999
1000         if (skb) {
1001                 int             ncb_len = 0;
1002                 __le16          *ntb_data;
1003                 __le16          *ntb_ndp;
1004                 int             dgram_pad;
1005
1006                 unsigned        max_size = ncm->port.fixed_in_len;
1007                 const struct ndp_parser_opts *opts = ncm->parser_opts;
1008                 const int ndp_align = le16_to_cpu(ntb_parameters.wNdpInAlignment);
1009                 const int div = le16_to_cpu(ntb_parameters.wNdpInDivisor);
1010                 const int rem = le16_to_cpu(ntb_parameters.wNdpInPayloadRemainder);
1011                 const int dgram_idx_len = 2 * 2 * opts->dgram_item_len;
1012
1013                 /* Add the CRC if required up front */
1014                 if (ncm->is_crc) {
1015                         uint32_t        crc;
1016                         __le16          *crc_pos;
1017
1018                         crc = ~crc32_le(~0,
1019                                         skb->data,
1020                                         skb->len);
1021                         crc_pos = skb_put(skb, sizeof(uint32_t));
1022                         put_unaligned_le32(crc, crc_pos);
1023                 }
1024
1025                 /* If the new skb is too big for the current NCM NTB then
1026                  * set the current stored skb to be sent now and clear it
1027                  * ready for new data.
1028                  * NOTE: Assume maximum align for speed of calculation.
1029                  */
1030                 if (ncm->skb_tx_data
1031                     && (ncm->ndp_dgram_count >= TX_MAX_NUM_DPE
1032                     || (ncm->skb_tx_data->len +
1033                     div + rem + skb->len +
1034                     ncm->skb_tx_ndp->len + ndp_align + (2 * dgram_idx_len))
1035                     > max_size)) {
1036                         skb2 = package_for_tx(ncm);
1037                         if (!skb2)
1038                                 goto err;
1039                 }
1040
1041                 if (!ncm->skb_tx_data) {
1042                         ncb_len = opts->nth_size;
1043                         dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1044                         ncb_len += dgram_pad;
1045
1046                         /* Create a new skb for the NTH and datagrams. */
1047                         ncm->skb_tx_data = alloc_skb(max_size, GFP_ATOMIC);
1048                         if (!ncm->skb_tx_data)
1049                                 goto err;
1050
1051                         ncm->skb_tx_data->dev = ncm->netdev;
1052                         ntb_data = skb_put_zero(ncm->skb_tx_data, ncb_len);
1053                         /* dwSignature */
1054                         put_unaligned_le32(opts->nth_sign, ntb_data);
1055                         ntb_data += 2;
1056                         /* wHeaderLength */
1057                         put_unaligned_le16(opts->nth_size, ntb_data++);
1058
1059                         /* Allocate an skb for storing the NDP,
1060                          * TX_MAX_NUM_DPE should easily suffice for a
1061                          * 16k packet.
1062                          */
1063                         ncm->skb_tx_ndp = alloc_skb((int)(opts->ndp_size
1064                                                     + opts->dpe_size
1065                                                     * TX_MAX_NUM_DPE),
1066                                                     GFP_ATOMIC);
1067                         if (!ncm->skb_tx_ndp)
1068                                 goto err;
1069
1070                         ncm->skb_tx_ndp->dev = ncm->netdev;
1071                         ntb_ndp = skb_put(ncm->skb_tx_ndp, opts->ndp_size);
1072                         memset(ntb_ndp, 0, ncb_len);
1073                         /* dwSignature */
1074                         put_unaligned_le32(ncm->ndp_sign, ntb_ndp);
1075                         ntb_ndp += 2;
1076
1077                         /* There is always a zeroed entry */
1078                         ncm->ndp_dgram_count = 1;
1079
1080                         /* Note: we skip opts->next_ndp_index */
1081
1082                         /* Start the timer. */
1083                         hrtimer_start(&ncm->task_timer, TX_TIMEOUT_NSECS,
1084                                       HRTIMER_MODE_REL_SOFT);
1085                 }
1086
1087                 /* Add the datagram position entries */
1088                 ntb_ndp = skb_put_zero(ncm->skb_tx_ndp, dgram_idx_len);
1089
1090                 ncb_len = ncm->skb_tx_data->len;
1091                 dgram_pad = ALIGN(ncb_len, div) + rem - ncb_len;
1092                 ncb_len += dgram_pad;
1093
1094                 /* (d)wDatagramIndex */
1095                 put_ncm(&ntb_ndp, opts->dgram_item_len, ncb_len);
1096                 /* (d)wDatagramLength */
1097                 put_ncm(&ntb_ndp, opts->dgram_item_len, skb->len);
1098                 ncm->ndp_dgram_count++;
1099
1100                 /* Add the new data to the skb */
1101                 skb_put_zero(ncm->skb_tx_data, dgram_pad);
1102                 skb_put_data(ncm->skb_tx_data, skb->data, skb->len);
1103                 dev_consume_skb_any(skb);
1104                 skb = NULL;
1105
1106         } else if (ncm->skb_tx_data) {
1107                 /* If we get here ncm_wrap_ntb() was called with NULL skb,
1108                  * because eth_start_xmit() was called with NULL skb by
1109                  * ncm_tx_timeout() - hence, this is our signal to flush/send.
1110                  */
1111                 skb2 = package_for_tx(ncm);
1112                 if (!skb2)
1113                         goto err;
1114         }
1115
1116         return skb2;
1117
1118 err:
1119         ncm->netdev->stats.tx_dropped++;
1120
1121         if (skb)
1122                 dev_kfree_skb_any(skb);
1123         if (ncm->skb_tx_data)
1124                 dev_kfree_skb_any(ncm->skb_tx_data);
1125         if (ncm->skb_tx_ndp)
1126                 dev_kfree_skb_any(ncm->skb_tx_ndp);
1127
1128         return NULL;
1129 }
1130
1131 /*
1132  * The transmit should only be run if no skb data has been sent
1133  * for a certain duration.
1134  */
1135 static enum hrtimer_restart ncm_tx_timeout(struct hrtimer *data)
1136 {
1137         struct f_ncm *ncm = container_of(data, struct f_ncm, task_timer);
1138         struct net_device *netdev = READ_ONCE(ncm->netdev);
1139
1140         if (netdev) {
1141                 /* XXX This allowance of a NULL skb argument to ndo_start_xmit
1142                  * XXX is not sane.  The gadget layer should be redesigned so
1143                  * XXX that the dev->wrap() invocations to build SKBs is transparent
1144                  * XXX and performed in some way outside of the ndo_start_xmit
1145                  * XXX interface.
1146                  *
1147                  * This will call directly into u_ether's eth_start_xmit()
1148                  */
1149                 netdev->netdev_ops->ndo_start_xmit(NULL, netdev);
1150         }
1151         return HRTIMER_NORESTART;
1152 }
1153
1154 static int ncm_unwrap_ntb(struct gether *port,
1155                           struct sk_buff *skb,
1156                           struct sk_buff_head *list)
1157 {
1158         struct f_ncm    *ncm = func_to_ncm(&port->func);
1159         unsigned char   *ntb_ptr = skb->data;
1160         __le16          *tmp;
1161         unsigned        index, index2;
1162         int             ndp_index;
1163         unsigned        dg_len, dg_len2;
1164         unsigned        ndp_len;
1165         unsigned        block_len;
1166         struct sk_buff  *skb2;
1167         int             ret = -EINVAL;
1168         unsigned        ntb_max = le32_to_cpu(ntb_parameters.dwNtbOutMaxSize);
1169         unsigned        frame_max = le16_to_cpu(ecm_desc.wMaxSegmentSize);
1170         const struct ndp_parser_opts *opts = ncm->parser_opts;
1171         unsigned        crc_len = ncm->is_crc ? sizeof(uint32_t) : 0;
1172         int             dgram_counter;
1173         int             to_process = skb->len;
1174
1175 parse_ntb:
1176         tmp = (__le16 *)ntb_ptr;
1177
1178         /* dwSignature */
1179         if (get_unaligned_le32(tmp) != opts->nth_sign) {
1180                 INFO(port->func.config->cdev, "Wrong NTH SIGN, skblen %d\n",
1181                         skb->len);
1182                 print_hex_dump(KERN_INFO, "HEAD:", DUMP_PREFIX_ADDRESS, 32, 1,
1183                                skb->data, 32, false);
1184
1185                 goto err;
1186         }
1187         tmp += 2;
1188         /* wHeaderLength */
1189         if (get_unaligned_le16(tmp++) != opts->nth_size) {
1190                 INFO(port->func.config->cdev, "Wrong NTB headersize\n");
1191                 goto err;
1192         }
1193         tmp++; /* skip wSequence */
1194
1195         block_len = get_ncm(&tmp, opts->block_length);
1196         /* (d)wBlockLength */
1197         if (block_len > ntb_max) {
1198                 INFO(port->func.config->cdev, "OUT size exceeded\n");
1199                 goto err;
1200         }
1201
1202         ndp_index = get_ncm(&tmp, opts->ndp_index);
1203
1204         /* Run through all the NDP's in the NTB */
1205         do {
1206                 /*
1207                  * NCM 3.2
1208                  * dwNdpIndex
1209                  */
1210                 if (((ndp_index % 4) != 0) ||
1211                                 (ndp_index < opts->nth_size) ||
1212                                 (ndp_index > (block_len -
1213                                               opts->ndp_size))) {
1214                         INFO(port->func.config->cdev, "Bad index: %#X\n",
1215                              ndp_index);
1216                         goto err;
1217                 }
1218
1219                 /*
1220                  * walk through NDP
1221                  * dwSignature
1222                  */
1223                 tmp = (__le16 *)(ntb_ptr + 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                  * wLength
1234                  * entry is 2 items
1235                  * item size is 16/32 bits, opts->dgram_item_len * 2 bytes
1236                  * minimal: struct usb_cdc_ncm_ndpX + normal entry + zero entry
1237                  * Each entry is a dgram index and a dgram length.
1238                  */
1239                 if ((ndp_len < opts->ndp_size
1240                                 + 2 * 2 * (opts->dgram_item_len * 2)) ||
1241                                 (ndp_len % opts->ndplen_align != 0)) {
1242                         INFO(port->func.config->cdev, "Bad NDP length: %#X\n",
1243                              ndp_len);
1244                         goto err;
1245                 }
1246                 tmp += opts->reserved1;
1247                 /* Check for another NDP (d)wNextNdpIndex */
1248                 ndp_index = get_ncm(&tmp, opts->next_ndp_index);
1249                 tmp += opts->reserved2;
1250
1251                 ndp_len -= opts->ndp_size;
1252                 index2 = get_ncm(&tmp, opts->dgram_item_len);
1253                 dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1254                 dgram_counter = 0;
1255
1256                 do {
1257                         index = index2;
1258                         /* wDatagramIndex[0] */
1259                         if ((index < opts->nth_size) ||
1260                                         (index > block_len - opts->dpe_size)) {
1261                                 INFO(port->func.config->cdev,
1262                                      "Bad index: %#X\n", index);
1263                                 goto err;
1264                         }
1265
1266                         dg_len = dg_len2;
1267                         /*
1268                          * wDatagramLength[0]
1269                          * ethernet hdr + crc or larger than max frame size
1270                          */
1271                         if ((dg_len < 14 + crc_len) ||
1272                                         (dg_len > frame_max)) {
1273                                 INFO(port->func.config->cdev,
1274                                      "Bad dgram length: %#X\n", dg_len);
1275                                 goto err;
1276                         }
1277                         if (ncm->is_crc) {
1278                                 uint32_t crc, crc2;
1279
1280                                 crc = get_unaligned_le32(ntb_ptr +
1281                                                          index + dg_len -
1282                                                          crc_len);
1283                                 crc2 = ~crc32_le(~0,
1284                                                  ntb_ptr + index,
1285                                                  dg_len - crc_len);
1286                                 if (crc != crc2) {
1287                                         INFO(port->func.config->cdev,
1288                                              "Bad CRC\n");
1289                                         goto err;
1290                                 }
1291                         }
1292
1293                         index2 = get_ncm(&tmp, opts->dgram_item_len);
1294                         dg_len2 = get_ncm(&tmp, opts->dgram_item_len);
1295
1296                         /* wDatagramIndex[1] */
1297                         if (index2 > block_len - opts->dpe_size) {
1298                                 INFO(port->func.config->cdev,
1299                                      "Bad index: %#X\n", index2);
1300                                 goto err;
1301                         }
1302
1303                         /*
1304                          * Copy the data into a new skb.
1305                          * This ensures the truesize is correct
1306                          */
1307                         skb2 = netdev_alloc_skb_ip_align(ncm->netdev,
1308                                                          dg_len - crc_len);
1309                         if (skb2 == NULL)
1310                                 goto err;
1311                         skb_put_data(skb2, ntb_ptr + index,
1312                                      dg_len - crc_len);
1313
1314                         skb_queue_tail(list, skb2);
1315
1316                         ndp_len -= 2 * (opts->dgram_item_len * 2);
1317
1318                         dgram_counter++;
1319                         if (index2 == 0 || dg_len2 == 0)
1320                                 break;
1321                 } while (ndp_len > 2 * (opts->dgram_item_len * 2));
1322         } while (ndp_index);
1323
1324         VDBG(port->func.config->cdev,
1325              "Parsed NTB with %d frames\n", dgram_counter);
1326
1327         to_process -= block_len;
1328
1329         /*
1330          * Windows NCM driver avoids USB ZLPs by adding a 1-byte
1331          * zero pad as needed.
1332          */
1333         if (to_process == 1 &&
1334             (*(unsigned char *)(ntb_ptr + block_len) == 0x00)) {
1335                 to_process--;
1336         } else if (to_process > 0) {
1337                 ntb_ptr = (unsigned char *)(ntb_ptr + block_len);
1338                 goto parse_ntb;
1339         }
1340
1341         dev_consume_skb_any(skb);
1342
1343         return 0;
1344 err:
1345         skb_queue_purge(list);
1346         dev_kfree_skb_any(skb);
1347         return ret;
1348 }
1349
1350 static void ncm_disable(struct usb_function *f)
1351 {
1352         struct f_ncm            *ncm = func_to_ncm(f);
1353         struct usb_composite_dev *cdev = f->config->cdev;
1354
1355         DBG(cdev, "ncm deactivated\n");
1356
1357         if (ncm->port.in_ep->enabled) {
1358                 ncm->netdev = NULL;
1359                 gether_disconnect(&ncm->port);
1360         }
1361
1362         if (ncm->notify->enabled) {
1363                 usb_ep_disable(ncm->notify);
1364                 ncm->notify->desc = NULL;
1365         }
1366 }
1367
1368 /*-------------------------------------------------------------------------*/
1369
1370 /*
1371  * Callbacks let us notify the host about connect/disconnect when the
1372  * net device is opened or closed.
1373  *
1374  * For testing, note that link states on this side include both opened
1375  * and closed variants of:
1376  *
1377  *   - disconnected/unconfigured
1378  *   - configured but inactive (data alt 0)
1379  *   - configured and active (data alt 1)
1380  *
1381  * Each needs to be tested with unplug, rmmod, SET_CONFIGURATION, and
1382  * SET_INTERFACE (altsetting).  Remember also that "configured" doesn't
1383  * imply the host is actually polling the notification endpoint, and
1384  * likewise that "active" doesn't imply it's actually using the data
1385  * endpoints for traffic.
1386  */
1387
1388 static void ncm_open(struct gether *geth)
1389 {
1390         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1391
1392         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1393
1394         spin_lock(&ncm->lock);
1395         ncm->is_open = true;
1396         ncm_notify(ncm);
1397         spin_unlock(&ncm->lock);
1398 }
1399
1400 static void ncm_close(struct gether *geth)
1401 {
1402         struct f_ncm            *ncm = func_to_ncm(&geth->func);
1403
1404         DBG(ncm->port.func.config->cdev, "%s\n", __func__);
1405
1406         spin_lock(&ncm->lock);
1407         ncm->is_open = false;
1408         ncm_notify(ncm);
1409         spin_unlock(&ncm->lock);
1410 }
1411
1412 /*-------------------------------------------------------------------------*/
1413
1414 /* ethernet function driver setup/binding */
1415
1416 static int ncm_bind(struct usb_configuration *c, struct usb_function *f)
1417 {
1418         struct usb_composite_dev *cdev = c->cdev;
1419         struct f_ncm            *ncm = func_to_ncm(f);
1420         struct usb_string       *us;
1421         int                     status = 0;
1422         struct usb_ep           *ep;
1423         struct f_ncm_opts       *ncm_opts;
1424
1425         if (!can_support_ecm(cdev->gadget))
1426                 return -EINVAL;
1427
1428         ncm_opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1429
1430         if (cdev->use_os_string) {
1431                 f->os_desc_table = kzalloc(sizeof(*f->os_desc_table),
1432                                            GFP_KERNEL);
1433                 if (!f->os_desc_table)
1434                         return -ENOMEM;
1435                 f->os_desc_n = 1;
1436                 f->os_desc_table[0].os_desc = &ncm_opts->ncm_os_desc;
1437         }
1438
1439         mutex_lock(&ncm_opts->lock);
1440         gether_set_gadget(ncm_opts->net, cdev->gadget);
1441         if (!ncm_opts->bound)
1442                 status = gether_register_netdev(ncm_opts->net);
1443         mutex_unlock(&ncm_opts->lock);
1444
1445         if (status)
1446                 goto fail;
1447
1448         ncm_opts->bound = true;
1449
1450         us = usb_gstrings_attach(cdev, ncm_strings,
1451                                  ARRAY_SIZE(ncm_string_defs));
1452         if (IS_ERR(us)) {
1453                 status = PTR_ERR(us);
1454                 goto fail;
1455         }
1456         ncm_control_intf.iInterface = us[STRING_CTRL_IDX].id;
1457         ncm_data_nop_intf.iInterface = us[STRING_DATA_IDX].id;
1458         ncm_data_intf.iInterface = us[STRING_DATA_IDX].id;
1459         ecm_desc.iMACAddress = us[STRING_MAC_IDX].id;
1460         ncm_iad_desc.iFunction = us[STRING_IAD_IDX].id;
1461
1462         /* allocate instance-specific interface IDs */
1463         status = usb_interface_id(c, f);
1464         if (status < 0)
1465                 goto fail;
1466         ncm->ctrl_id = status;
1467         ncm_iad_desc.bFirstInterface = status;
1468
1469         ncm_control_intf.bInterfaceNumber = status;
1470         ncm_union_desc.bMasterInterface0 = status;
1471
1472         if (cdev->use_os_string)
1473                 f->os_desc_table[0].if_id =
1474                         ncm_iad_desc.bFirstInterface;
1475
1476         status = usb_interface_id(c, f);
1477         if (status < 0)
1478                 goto fail;
1479         ncm->data_id = status;
1480
1481         ncm_data_nop_intf.bInterfaceNumber = status;
1482         ncm_data_intf.bInterfaceNumber = status;
1483         ncm_union_desc.bSlaveInterface0 = status;
1484
1485         status = -ENODEV;
1486
1487         /* allocate instance-specific endpoints */
1488         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_in_desc);
1489         if (!ep)
1490                 goto fail;
1491         ncm->port.in_ep = ep;
1492
1493         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_out_desc);
1494         if (!ep)
1495                 goto fail;
1496         ncm->port.out_ep = ep;
1497
1498         ep = usb_ep_autoconfig(cdev->gadget, &fs_ncm_notify_desc);
1499         if (!ep)
1500                 goto fail;
1501         ncm->notify = ep;
1502
1503         status = -ENOMEM;
1504
1505         /* allocate notification request and buffer */
1506         ncm->notify_req = usb_ep_alloc_request(ep, GFP_KERNEL);
1507         if (!ncm->notify_req)
1508                 goto fail;
1509         ncm->notify_req->buf = kmalloc(NCM_STATUS_BYTECOUNT, GFP_KERNEL);
1510         if (!ncm->notify_req->buf)
1511                 goto fail;
1512         ncm->notify_req->context = ncm;
1513         ncm->notify_req->complete = ncm_notify_complete;
1514
1515         /*
1516          * support all relevant hardware speeds... we expect that when
1517          * hardware is dual speed, all bulk-capable endpoints work at
1518          * both speeds
1519          */
1520         hs_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1521         hs_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1522         hs_ncm_notify_desc.bEndpointAddress =
1523                 fs_ncm_notify_desc.bEndpointAddress;
1524
1525         ss_ncm_in_desc.bEndpointAddress = fs_ncm_in_desc.bEndpointAddress;
1526         ss_ncm_out_desc.bEndpointAddress = fs_ncm_out_desc.bEndpointAddress;
1527         ss_ncm_notify_desc.bEndpointAddress =
1528                 fs_ncm_notify_desc.bEndpointAddress;
1529
1530         status = usb_assign_descriptors(f, ncm_fs_function, ncm_hs_function,
1531                         ncm_ss_function, ncm_ss_function);
1532         if (status)
1533                 goto fail;
1534
1535         /*
1536          * NOTE:  all that is done without knowing or caring about
1537          * the network link ... which is unavailable to this code
1538          * until we're activated via set_alt().
1539          */
1540
1541         ncm->port.open = ncm_open;
1542         ncm->port.close = ncm_close;
1543
1544         hrtimer_init(&ncm->task_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
1545         ncm->task_timer.function = ncm_tx_timeout;
1546
1547         DBG(cdev, "CDC Network: IN/%s OUT/%s NOTIFY/%s\n",
1548                         ncm->port.in_ep->name, ncm->port.out_ep->name,
1549                         ncm->notify->name);
1550         return 0;
1551
1552 fail:
1553         kfree(f->os_desc_table);
1554         f->os_desc_n = 0;
1555
1556         if (ncm->notify_req) {
1557                 kfree(ncm->notify_req->buf);
1558                 usb_ep_free_request(ncm->notify, ncm->notify_req);
1559         }
1560
1561         ERROR(cdev, "%s: can't bind, err %d\n", f->name, status);
1562
1563         return status;
1564 }
1565
1566 static inline struct f_ncm_opts *to_f_ncm_opts(struct config_item *item)
1567 {
1568         return container_of(to_config_group(item), struct f_ncm_opts,
1569                             func_inst.group);
1570 }
1571
1572 /* f_ncm_item_ops */
1573 USB_ETHERNET_CONFIGFS_ITEM(ncm);
1574
1575 /* f_ncm_opts_dev_addr */
1576 USB_ETHERNET_CONFIGFS_ITEM_ATTR_DEV_ADDR(ncm);
1577
1578 /* f_ncm_opts_host_addr */
1579 USB_ETHERNET_CONFIGFS_ITEM_ATTR_HOST_ADDR(ncm);
1580
1581 /* f_ncm_opts_qmult */
1582 USB_ETHERNET_CONFIGFS_ITEM_ATTR_QMULT(ncm);
1583
1584 /* f_ncm_opts_ifname */
1585 USB_ETHERNET_CONFIGFS_ITEM_ATTR_IFNAME(ncm);
1586
1587 static struct configfs_attribute *ncm_attrs[] = {
1588         &ncm_opts_attr_dev_addr,
1589         &ncm_opts_attr_host_addr,
1590         &ncm_opts_attr_qmult,
1591         &ncm_opts_attr_ifname,
1592         NULL,
1593 };
1594
1595 static const struct config_item_type ncm_func_type = {
1596         .ct_item_ops    = &ncm_item_ops,
1597         .ct_attrs       = ncm_attrs,
1598         .ct_owner       = THIS_MODULE,
1599 };
1600
1601 static void ncm_free_inst(struct usb_function_instance *f)
1602 {
1603         struct f_ncm_opts *opts;
1604
1605         opts = container_of(f, struct f_ncm_opts, func_inst);
1606         if (opts->bound)
1607                 gether_cleanup(netdev_priv(opts->net));
1608         else
1609                 free_netdev(opts->net);
1610         kfree(opts->ncm_interf_group);
1611         kfree(opts);
1612 }
1613
1614 static struct usb_function_instance *ncm_alloc_inst(void)
1615 {
1616         struct f_ncm_opts *opts;
1617         struct usb_os_desc *descs[1];
1618         char *names[1];
1619         struct config_group *ncm_interf_group;
1620
1621         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1622         if (!opts)
1623                 return ERR_PTR(-ENOMEM);
1624         opts->ncm_os_desc.ext_compat_id = opts->ncm_ext_compat_id;
1625
1626         mutex_init(&opts->lock);
1627         opts->func_inst.free_func_inst = ncm_free_inst;
1628         opts->net = gether_setup_default();
1629         if (IS_ERR(opts->net)) {
1630                 struct net_device *net = opts->net;
1631                 kfree(opts);
1632                 return ERR_CAST(net);
1633         }
1634         INIT_LIST_HEAD(&opts->ncm_os_desc.ext_prop);
1635
1636         descs[0] = &opts->ncm_os_desc;
1637         names[0] = "ncm";
1638
1639         config_group_init_type_name(&opts->func_inst.group, "", &ncm_func_type);
1640         ncm_interf_group =
1641                 usb_os_desc_prepare_interf_dir(&opts->func_inst.group, 1, descs,
1642                                                names, THIS_MODULE);
1643         if (IS_ERR(ncm_interf_group)) {
1644                 ncm_free_inst(&opts->func_inst);
1645                 return ERR_CAST(ncm_interf_group);
1646         }
1647         opts->ncm_interf_group = ncm_interf_group;
1648
1649         return &opts->func_inst;
1650 }
1651
1652 static void ncm_free(struct usb_function *f)
1653 {
1654         struct f_ncm *ncm;
1655         struct f_ncm_opts *opts;
1656
1657         ncm = func_to_ncm(f);
1658         opts = container_of(f->fi, struct f_ncm_opts, func_inst);
1659         kfree(ncm);
1660         mutex_lock(&opts->lock);
1661         opts->refcnt--;
1662         mutex_unlock(&opts->lock);
1663 }
1664
1665 static void ncm_unbind(struct usb_configuration *c, struct usb_function *f)
1666 {
1667         struct f_ncm *ncm = func_to_ncm(f);
1668
1669         DBG(c->cdev, "ncm unbind\n");
1670
1671         hrtimer_cancel(&ncm->task_timer);
1672
1673         kfree(f->os_desc_table);
1674         f->os_desc_n = 0;
1675
1676         ncm_string_defs[0].id = 0;
1677         usb_free_all_descriptors(f);
1678
1679         if (atomic_read(&ncm->notify_count)) {
1680                 usb_ep_dequeue(ncm->notify, ncm->notify_req);
1681                 atomic_set(&ncm->notify_count, 0);
1682         }
1683
1684         kfree(ncm->notify_req->buf);
1685         usb_ep_free_request(ncm->notify, ncm->notify_req);
1686 }
1687
1688 static struct usb_function *ncm_alloc(struct usb_function_instance *fi)
1689 {
1690         struct f_ncm            *ncm;
1691         struct f_ncm_opts       *opts;
1692         int status;
1693
1694         /* allocate and initialize one new instance */
1695         ncm = kzalloc(sizeof(*ncm), GFP_KERNEL);
1696         if (!ncm)
1697                 return ERR_PTR(-ENOMEM);
1698
1699         opts = container_of(fi, struct f_ncm_opts, func_inst);
1700         mutex_lock(&opts->lock);
1701         opts->refcnt++;
1702
1703         /* export host's Ethernet address in CDC format */
1704         status = gether_get_host_addr_cdc(opts->net, ncm->ethaddr,
1705                                       sizeof(ncm->ethaddr));
1706         if (status < 12) { /* strlen("01234567890a") */
1707                 kfree(ncm);
1708                 mutex_unlock(&opts->lock);
1709                 return ERR_PTR(-EINVAL);
1710         }
1711         ncm_string_defs[STRING_MAC_IDX].s = ncm->ethaddr;
1712
1713         spin_lock_init(&ncm->lock);
1714         ncm_reset_values(ncm);
1715         ncm->port.ioport = netdev_priv(opts->net);
1716         mutex_unlock(&opts->lock);
1717         ncm->port.is_fixed = true;
1718         ncm->port.supports_multi_frame = true;
1719
1720         ncm->port.func.name = "cdc_network";
1721         /* descriptors are per-instance copies */
1722         ncm->port.func.bind = ncm_bind;
1723         ncm->port.func.unbind = ncm_unbind;
1724         ncm->port.func.set_alt = ncm_set_alt;
1725         ncm->port.func.get_alt = ncm_get_alt;
1726         ncm->port.func.setup = ncm_setup;
1727         ncm->port.func.disable = ncm_disable;
1728         ncm->port.func.free_func = ncm_free;
1729
1730         ncm->port.wrap = ncm_wrap_ntb;
1731         ncm->port.unwrap = ncm_unwrap_ntb;
1732
1733         return &ncm->port.func;
1734 }
1735
1736 DECLARE_USB_FUNCTION_INIT(ncm, ncm_alloc_inst, ncm_alloc);
1737 MODULE_LICENSE("GPL");
1738 MODULE_AUTHOR("Yauheni Kaliuta");