linux/drivers/net/can/usb/esd_usb2.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * CAN driver for esd CAN-USB/2 and CAN-USB/Micro
   4 *
   5 * Copyright (C) 2010-2012 Matthias Fuchs <matthias.fuchs@esd.eu>, esd gmbh
   6 */
   7#include <linux/signal.h>
   8#include <linux/slab.h>
   9#include <linux/module.h>
  10#include <linux/netdevice.h>
  11#include <linux/usb.h>
  12
  13#include <linux/can.h>
  14#include <linux/can/dev.h>
  15#include <linux/can/error.h>
  16
  17MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
  18MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 and CAN-USB/Micro interfaces");
  19MODULE_LICENSE("GPL v2");
  20
  21/* Define these values to match your devices */
  22#define USB_ESDGMBH_VENDOR_ID   0x0ab4
  23#define USB_CANUSB2_PRODUCT_ID  0x0010
  24#define USB_CANUSBM_PRODUCT_ID  0x0011
  25
  26#define ESD_USB2_CAN_CLOCK      60000000
  27#define ESD_USBM_CAN_CLOCK      36000000
  28#define ESD_USB2_MAX_NETS       2
  29
  30/* USB2 commands */
  31#define CMD_VERSION             1 /* also used for VERSION_REPLY */
  32#define CMD_CAN_RX              2 /* device to host only */
  33#define CMD_CAN_TX              3 /* also used for TX_DONE */
  34#define CMD_SETBAUD             4 /* also used for SETBAUD_REPLY */
  35#define CMD_TS                  5 /* also used for TS_REPLY */
  36#define CMD_IDADD               6 /* also used for IDADD_REPLY */
  37
  38/* esd CAN message flags - dlc field */
  39#define ESD_RTR                 0x10
  40
  41/* esd CAN message flags - id field */
  42#define ESD_EXTID               0x20000000
  43#define ESD_EVENT               0x40000000
  44#define ESD_IDMASK              0x1fffffff
  45
  46/* esd CAN event ids used by this driver */
  47#define ESD_EV_CAN_ERROR_EXT    2
  48
  49/* baudrate message flags */
  50#define ESD_USB2_UBR            0x80000000
  51#define ESD_USB2_LOM            0x40000000
  52#define ESD_USB2_NO_BAUDRATE    0x7fffffff
  53#define ESD_USB2_TSEG1_MIN      1
  54#define ESD_USB2_TSEG1_MAX      16
  55#define ESD_USB2_TSEG1_SHIFT    16
  56#define ESD_USB2_TSEG2_MIN      1
  57#define ESD_USB2_TSEG2_MAX      8
  58#define ESD_USB2_TSEG2_SHIFT    20
  59#define ESD_USB2_SJW_MAX        4
  60#define ESD_USB2_SJW_SHIFT      14
  61#define ESD_USBM_SJW_SHIFT      24
  62#define ESD_USB2_BRP_MIN        1
  63#define ESD_USB2_BRP_MAX        1024
  64#define ESD_USB2_BRP_INC        1
  65#define ESD_USB2_3_SAMPLES      0x00800000
  66
  67/* esd IDADD message */
  68#define ESD_ID_ENABLE           0x80
  69#define ESD_MAX_ID_SEGMENT      64
  70
  71/* SJA1000 ECC register (emulated by usb2 firmware) */
  72#define SJA1000_ECC_SEG         0x1F
  73#define SJA1000_ECC_DIR         0x20
  74#define SJA1000_ECC_ERR         0x06
  75#define SJA1000_ECC_BIT         0x00
  76#define SJA1000_ECC_FORM        0x40
  77#define SJA1000_ECC_STUFF       0x80
  78#define SJA1000_ECC_MASK        0xc0
  79
  80/* esd bus state event codes */
  81#define ESD_BUSSTATE_MASK       0xc0
  82#define ESD_BUSSTATE_WARN       0x40
  83#define ESD_BUSSTATE_ERRPASSIVE 0x80
  84#define ESD_BUSSTATE_BUSOFF     0xc0
  85
  86#define RX_BUFFER_SIZE          1024
  87#define MAX_RX_URBS             4
  88#define MAX_TX_URBS             16 /* must be power of 2 */
  89
  90struct header_msg {
  91        u8 len; /* len is always the total message length in 32bit words */
  92        u8 cmd;
  93        u8 rsvd[2];
  94};
  95
  96struct version_msg {
  97        u8 len;
  98        u8 cmd;
  99        u8 rsvd;
 100        u8 flags;
 101        __le32 drv_version;
 102};
 103
 104struct version_reply_msg {
 105        u8 len;
 106        u8 cmd;
 107        u8 nets;
 108        u8 features;
 109        __le32 version;
 110        u8 name[16];
 111        __le32 rsvd;
 112        __le32 ts;
 113};
 114
 115struct rx_msg {
 116        u8 len;
 117        u8 cmd;
 118        u8 net;
 119        u8 dlc;
 120        __le32 ts;
 121        __le32 id; /* upper 3 bits contain flags */
 122        u8 data[8];
 123};
 124
 125struct tx_msg {
 126        u8 len;
 127        u8 cmd;
 128        u8 net;
 129        u8 dlc;
 130        u32 hnd;        /* opaque handle, not used by device */
 131        __le32 id; /* upper 3 bits contain flags */
 132        u8 data[8];
 133};
 134
 135struct tx_done_msg {
 136        u8 len;
 137        u8 cmd;
 138        u8 net;
 139        u8 status;
 140        u32 hnd;        /* opaque handle, not used by device */
 141        __le32 ts;
 142};
 143
 144struct id_filter_msg {
 145        u8 len;
 146        u8 cmd;
 147        u8 net;
 148        u8 option;
 149        __le32 mask[ESD_MAX_ID_SEGMENT + 1];
 150};
 151
 152struct set_baudrate_msg {
 153        u8 len;
 154        u8 cmd;
 155        u8 net;
 156        u8 rsvd;
 157        __le32 baud;
 158};
 159
 160/* Main message type used between library and application */
 161struct __attribute__ ((packed)) esd_usb2_msg {
 162        union {
 163                struct header_msg hdr;
 164                struct version_msg version;
 165                struct version_reply_msg version_reply;
 166                struct rx_msg rx;
 167                struct tx_msg tx;
 168                struct tx_done_msg txdone;
 169                struct set_baudrate_msg setbaud;
 170                struct id_filter_msg filter;
 171        } msg;
 172};
 173
 174static struct usb_device_id esd_usb2_table[] = {
 175        {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
 176        {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSBM_PRODUCT_ID)},
 177        {}
 178};
 179MODULE_DEVICE_TABLE(usb, esd_usb2_table);
 180
 181struct esd_usb2_net_priv;
 182
 183struct esd_tx_urb_context {
 184        struct esd_usb2_net_priv *priv;
 185        u32 echo_index;
 186        int dlc;
 187};
 188
 189struct esd_usb2 {
 190        struct usb_device *udev;
 191        struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
 192
 193        struct usb_anchor rx_submitted;
 194
 195        int net_count;
 196        u32 version;
 197        int rxinitdone;
 198};
 199
 200struct esd_usb2_net_priv {
 201        struct can_priv can; /* must be the first member */
 202
 203        atomic_t active_tx_jobs;
 204        struct usb_anchor tx_submitted;
 205        struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
 206
 207        struct esd_usb2 *usb2;
 208        struct net_device *netdev;
 209        int index;
 210        u8 old_state;
 211        struct can_berr_counter bec;
 212};
 213
 214static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
 215                              struct esd_usb2_msg *msg)
 216{
 217        struct net_device_stats *stats = &priv->netdev->stats;
 218        struct can_frame *cf;
 219        struct sk_buff *skb;
 220        u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
 221
 222        if (id == ESD_EV_CAN_ERROR_EXT) {
 223                u8 state = msg->msg.rx.data[0];
 224                u8 ecc = msg->msg.rx.data[1];
 225                u8 txerr = msg->msg.rx.data[2];
 226                u8 rxerr = msg->msg.rx.data[3];
 227
 228                skb = alloc_can_err_skb(priv->netdev, &cf);
 229                if (skb == NULL) {
 230                        stats->rx_dropped++;
 231                        return;
 232                }
 233
 234                if (state != priv->old_state) {
 235                        priv->old_state = state;
 236
 237                        switch (state & ESD_BUSSTATE_MASK) {
 238                        case ESD_BUSSTATE_BUSOFF:
 239                                priv->can.state = CAN_STATE_BUS_OFF;
 240                                cf->can_id |= CAN_ERR_BUSOFF;
 241                                priv->can.can_stats.bus_off++;
 242                                can_bus_off(priv->netdev);
 243                                break;
 244                        case ESD_BUSSTATE_WARN:
 245                                priv->can.state = CAN_STATE_ERROR_WARNING;
 246                                priv->can.can_stats.error_warning++;
 247                                break;
 248                        case ESD_BUSSTATE_ERRPASSIVE:
 249                                priv->can.state = CAN_STATE_ERROR_PASSIVE;
 250                                priv->can.can_stats.error_passive++;
 251                                break;
 252                        default:
 253                                priv->can.state = CAN_STATE_ERROR_ACTIVE;
 254                                break;
 255                        }
 256                } else {
 257                        priv->can.can_stats.bus_error++;
 258                        stats->rx_errors++;
 259
 260                        cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 261
 262                        switch (ecc & SJA1000_ECC_MASK) {
 263                        case SJA1000_ECC_BIT:
 264                                cf->data[2] |= CAN_ERR_PROT_BIT;
 265                                break;
 266                        case SJA1000_ECC_FORM:
 267                                cf->data[2] |= CAN_ERR_PROT_FORM;
 268                                break;
 269                        case SJA1000_ECC_STUFF:
 270                                cf->data[2] |= CAN_ERR_PROT_STUFF;
 271                                break;
 272                        default:
 273                                cf->data[3] = ecc & SJA1000_ECC_SEG;
 274                                break;
 275                        }
 276
 277                        /* Error occurred during transmission? */
 278                        if (!(ecc & SJA1000_ECC_DIR))
 279                                cf->data[2] |= CAN_ERR_PROT_TX;
 280
 281                        if (priv->can.state == CAN_STATE_ERROR_WARNING ||
 282                            priv->can.state == CAN_STATE_ERROR_PASSIVE) {
 283                                cf->data[1] = (txerr > rxerr) ?
 284                                        CAN_ERR_CRTL_TX_PASSIVE :
 285                                        CAN_ERR_CRTL_RX_PASSIVE;
 286                        }
 287                        cf->data[6] = txerr;
 288                        cf->data[7] = rxerr;
 289                }
 290
 291                priv->bec.txerr = txerr;
 292                priv->bec.rxerr = rxerr;
 293
 294                stats->rx_packets++;
 295                stats->rx_bytes += cf->can_dlc;
 296                netif_rx(skb);
 297        }
 298}
 299
 300static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
 301                                struct esd_usb2_msg *msg)
 302{
 303        struct net_device_stats *stats = &priv->netdev->stats;
 304        struct can_frame *cf;
 305        struct sk_buff *skb;
 306        int i;
 307        u32 id;
 308
 309        if (!netif_device_present(priv->netdev))
 310                return;
 311
 312        id = le32_to_cpu(msg->msg.rx.id);
 313
 314        if (id & ESD_EVENT) {
 315                esd_usb2_rx_event(priv, msg);
 316        } else {
 317                skb = alloc_can_skb(priv->netdev, &cf);
 318                if (skb == NULL) {
 319                        stats->rx_dropped++;
 320                        return;
 321                }
 322
 323                cf->can_id = id & ESD_IDMASK;
 324                cf->can_dlc = get_can_dlc(msg->msg.rx.dlc & ~ESD_RTR);
 325
 326                if (id & ESD_EXTID)
 327                        cf->can_id |= CAN_EFF_FLAG;
 328
 329                if (msg->msg.rx.dlc & ESD_RTR) {
 330                        cf->can_id |= CAN_RTR_FLAG;
 331                } else {
 332                        for (i = 0; i < cf->can_dlc; i++)
 333                                cf->data[i] = msg->msg.rx.data[i];
 334                }
 335
 336                stats->rx_packets++;
 337                stats->rx_bytes += cf->can_dlc;
 338                netif_rx(skb);
 339        }
 340
 341        return;
 342}
 343
 344static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
 345                                 struct esd_usb2_msg *msg)
 346{
 347        struct net_device_stats *stats = &priv->netdev->stats;
 348        struct net_device *netdev = priv->netdev;
 349        struct esd_tx_urb_context *context;
 350
 351        if (!netif_device_present(netdev))
 352                return;
 353
 354        context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
 355
 356        if (!msg->msg.txdone.status) {
 357                stats->tx_packets++;
 358                stats->tx_bytes += context->dlc;
 359                can_get_echo_skb(netdev, context->echo_index);
 360        } else {
 361                stats->tx_errors++;
 362                can_free_echo_skb(netdev, context->echo_index);
 363        }
 364
 365        /* Release context */
 366        context->echo_index = MAX_TX_URBS;
 367        atomic_dec(&priv->active_tx_jobs);
 368
 369        netif_wake_queue(netdev);
 370}
 371
 372static void esd_usb2_read_bulk_callback(struct urb *urb)
 373{
 374        struct esd_usb2 *dev = urb->context;
 375        int retval;
 376        int pos = 0;
 377        int i;
 378
 379        switch (urb->status) {
 380        case 0: /* success */
 381                break;
 382
 383        case -ENOENT:
 384        case -EPIPE:
 385        case -EPROTO:
 386        case -ESHUTDOWN:
 387                return;
 388
 389        default:
 390                dev_info(dev->udev->dev.parent,
 391                         "Rx URB aborted (%d)\n", urb->status);
 392                goto resubmit_urb;
 393        }
 394
 395        while (pos < urb->actual_length) {
 396                struct esd_usb2_msg *msg;
 397
 398                msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
 399
 400                switch (msg->msg.hdr.cmd) {
 401                case CMD_CAN_RX:
 402                        if (msg->msg.rx.net >= dev->net_count) {
 403                                dev_err(dev->udev->dev.parent, "format error\n");
 404                                break;
 405                        }
 406
 407                        esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
 408                        break;
 409
 410                case CMD_CAN_TX:
 411                        if (msg->msg.txdone.net >= dev->net_count) {
 412                                dev_err(dev->udev->dev.parent, "format error\n");
 413                                break;
 414                        }
 415
 416                        esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
 417                                             msg);
 418                        break;
 419                }
 420
 421                pos += msg->msg.hdr.len << 2;
 422
 423                if (pos > urb->actual_length) {
 424                        dev_err(dev->udev->dev.parent, "format error\n");
 425                        break;
 426                }
 427        }
 428
 429resubmit_urb:
 430        usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
 431                          urb->transfer_buffer, RX_BUFFER_SIZE,
 432                          esd_usb2_read_bulk_callback, dev);
 433
 434        retval = usb_submit_urb(urb, GFP_ATOMIC);
 435        if (retval == -ENODEV) {
 436                for (i = 0; i < dev->net_count; i++) {
 437                        if (dev->nets[i])
 438                                netif_device_detach(dev->nets[i]->netdev);
 439                }
 440        } else if (retval) {
 441                dev_err(dev->udev->dev.parent,
 442                        "failed resubmitting read bulk urb: %d\n", retval);
 443        }
 444
 445        return;
 446}
 447
 448/*
 449 * callback for bulk IN urb
 450 */
 451static void esd_usb2_write_bulk_callback(struct urb *urb)
 452{
 453        struct esd_tx_urb_context *context = urb->context;
 454        struct esd_usb2_net_priv *priv;
 455        struct net_device *netdev;
 456        size_t size = sizeof(struct esd_usb2_msg);
 457
 458        WARN_ON(!context);
 459
 460        priv = context->priv;
 461        netdev = priv->netdev;
 462
 463        /* free up our allocated buffer */
 464        usb_free_coherent(urb->dev, size,
 465                          urb->transfer_buffer, urb->transfer_dma);
 466
 467        if (!netif_device_present(netdev))
 468                return;
 469
 470        if (urb->status)
 471                netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
 472
 473        netif_trans_update(netdev);
 474}
 475
 476static ssize_t show_firmware(struct device *d,
 477                             struct device_attribute *attr, char *buf)
 478{
 479        struct usb_interface *intf = to_usb_interface(d);
 480        struct esd_usb2 *dev = usb_get_intfdata(intf);
 481
 482        return sprintf(buf, "%d.%d.%d\n",
 483                       (dev->version >> 12) & 0xf,
 484                       (dev->version >> 8) & 0xf,
 485                       dev->version & 0xff);
 486}
 487static DEVICE_ATTR(firmware, 0444, show_firmware, NULL);
 488
 489static ssize_t show_hardware(struct device *d,
 490                             struct device_attribute *attr, char *buf)
 491{
 492        struct usb_interface *intf = to_usb_interface(d);
 493        struct esd_usb2 *dev = usb_get_intfdata(intf);
 494
 495        return sprintf(buf, "%d.%d.%d\n",
 496                       (dev->version >> 28) & 0xf,
 497                       (dev->version >> 24) & 0xf,
 498                       (dev->version >> 16) & 0xff);
 499}
 500static DEVICE_ATTR(hardware, 0444, show_hardware, NULL);
 501
 502static ssize_t show_nets(struct device *d,
 503                         struct device_attribute *attr, char *buf)
 504{
 505        struct usb_interface *intf = to_usb_interface(d);
 506        struct esd_usb2 *dev = usb_get_intfdata(intf);
 507
 508        return sprintf(buf, "%d", dev->net_count);
 509}
 510static DEVICE_ATTR(nets, 0444, show_nets, NULL);
 511
 512static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
 513{
 514        int actual_length;
 515
 516        return usb_bulk_msg(dev->udev,
 517                            usb_sndbulkpipe(dev->udev, 2),
 518                            msg,
 519                            msg->msg.hdr.len << 2,
 520                            &actual_length,
 521                            1000);
 522}
 523
 524static int esd_usb2_wait_msg(struct esd_usb2 *dev,
 525                             struct esd_usb2_msg *msg)
 526{
 527        int actual_length;
 528
 529        return usb_bulk_msg(dev->udev,
 530                            usb_rcvbulkpipe(dev->udev, 1),
 531                            msg,
 532                            sizeof(*msg),
 533                            &actual_length,
 534                            1000);
 535}
 536
 537static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
 538{
 539        int i, err = 0;
 540
 541        if (dev->rxinitdone)
 542                return 0;
 543
 544        for (i = 0; i < MAX_RX_URBS; i++) {
 545                struct urb *urb = NULL;
 546                u8 *buf = NULL;
 547
 548                /* create a URB, and a buffer for it */
 549                urb = usb_alloc_urb(0, GFP_KERNEL);
 550                if (!urb) {
 551                        err = -ENOMEM;
 552                        break;
 553                }
 554
 555                buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
 556                                         &urb->transfer_dma);
 557                if (!buf) {
 558                        dev_warn(dev->udev->dev.parent,
 559                                 "No memory left for USB buffer\n");
 560                        err = -ENOMEM;
 561                        goto freeurb;
 562                }
 563
 564                usb_fill_bulk_urb(urb, dev->udev,
 565                                  usb_rcvbulkpipe(dev->udev, 1),
 566                                  buf, RX_BUFFER_SIZE,
 567                                  esd_usb2_read_bulk_callback, dev);
 568                urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 569                usb_anchor_urb(urb, &dev->rx_submitted);
 570
 571                err = usb_submit_urb(urb, GFP_KERNEL);
 572                if (err) {
 573                        usb_unanchor_urb(urb);
 574                        usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
 575                                          urb->transfer_dma);
 576                }
 577
 578freeurb:
 579                /* Drop reference, USB core will take care of freeing it */
 580                usb_free_urb(urb);
 581                if (err)
 582                        break;
 583        }
 584
 585        /* Did we submit any URBs */
 586        if (i == 0) {
 587                dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
 588                return err;
 589        }
 590
 591        /* Warn if we've couldn't transmit all the URBs */
 592        if (i < MAX_RX_URBS) {
 593                dev_warn(dev->udev->dev.parent,
 594                         "rx performance may be slow\n");
 595        }
 596
 597        dev->rxinitdone = 1;
 598        return 0;
 599}
 600
 601/*
 602 * Start interface
 603 */
 604static int esd_usb2_start(struct esd_usb2_net_priv *priv)
 605{
 606        struct esd_usb2 *dev = priv->usb2;
 607        struct net_device *netdev = priv->netdev;
 608        struct esd_usb2_msg *msg;
 609        int err, i;
 610
 611        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 612        if (!msg) {
 613                err = -ENOMEM;
 614                goto out;
 615        }
 616
 617        /*
 618         * Enable all IDs
 619         * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
 620         * Each bit represents one 11 bit CAN identifier. A set bit
 621         * enables reception of the corresponding CAN identifier. A cleared
 622         * bit disabled this identifier. An additional bitmask value
 623         * following the CAN 2.0A bits is used to enable reception of
 624         * extended CAN frames. Only the LSB of this final mask is checked
 625         * for the complete 29 bit ID range. The IDADD message also allows
 626         * filter configuration for an ID subset. In this case you can add
 627         * the number of the starting bitmask (0..64) to the filter.option
 628         * field followed by only some bitmasks.
 629         */
 630        msg->msg.hdr.cmd = CMD_IDADD;
 631        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 632        msg->msg.filter.net = priv->index;
 633        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 634        for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
 635                msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
 636        /* enable 29bit extended IDs */
 637        msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
 638
 639        err = esd_usb2_send_msg(dev, msg);
 640        if (err)
 641                goto out;
 642
 643        err = esd_usb2_setup_rx_urbs(dev);
 644        if (err)
 645                goto out;
 646
 647        priv->can.state = CAN_STATE_ERROR_ACTIVE;
 648
 649out:
 650        if (err == -ENODEV)
 651                netif_device_detach(netdev);
 652        if (err)
 653                netdev_err(netdev, "couldn't start device: %d\n", err);
 654
 655        kfree(msg);
 656        return err;
 657}
 658
 659static void unlink_all_urbs(struct esd_usb2 *dev)
 660{
 661        struct esd_usb2_net_priv *priv;
 662        int i, j;
 663
 664        usb_kill_anchored_urbs(&dev->rx_submitted);
 665        for (i = 0; i < dev->net_count; i++) {
 666                priv = dev->nets[i];
 667                if (priv) {
 668                        usb_kill_anchored_urbs(&priv->tx_submitted);
 669                        atomic_set(&priv->active_tx_jobs, 0);
 670
 671                        for (j = 0; j < MAX_TX_URBS; j++)
 672                                priv->tx_contexts[j].echo_index = MAX_TX_URBS;
 673                }
 674        }
 675}
 676
 677static int esd_usb2_open(struct net_device *netdev)
 678{
 679        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 680        int err;
 681
 682        /* common open */
 683        err = open_candev(netdev);
 684        if (err)
 685                return err;
 686
 687        /* finally start device */
 688        err = esd_usb2_start(priv);
 689        if (err) {
 690                netdev_warn(netdev, "couldn't start device: %d\n", err);
 691                close_candev(netdev);
 692                return err;
 693        }
 694
 695        netif_start_queue(netdev);
 696
 697        return 0;
 698}
 699
 700static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
 701                                      struct net_device *netdev)
 702{
 703        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 704        struct esd_usb2 *dev = priv->usb2;
 705        struct esd_tx_urb_context *context = NULL;
 706        struct net_device_stats *stats = &netdev->stats;
 707        struct can_frame *cf = (struct can_frame *)skb->data;
 708        struct esd_usb2_msg *msg;
 709        struct urb *urb;
 710        u8 *buf;
 711        int i, err;
 712        int ret = NETDEV_TX_OK;
 713        size_t size = sizeof(struct esd_usb2_msg);
 714
 715        if (can_dropped_invalid_skb(netdev, skb))
 716                return NETDEV_TX_OK;
 717
 718        /* create a URB, and a buffer for it, and copy the data to the URB */
 719        urb = usb_alloc_urb(0, GFP_ATOMIC);
 720        if (!urb) {
 721                stats->tx_dropped++;
 722                dev_kfree_skb(skb);
 723                goto nourbmem;
 724        }
 725
 726        buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
 727                                 &urb->transfer_dma);
 728        if (!buf) {
 729                netdev_err(netdev, "No memory left for USB buffer\n");
 730                stats->tx_dropped++;
 731                dev_kfree_skb(skb);
 732                goto nobufmem;
 733        }
 734
 735        msg = (struct esd_usb2_msg *)buf;
 736
 737        msg->msg.hdr.len = 3; /* minimal length */
 738        msg->msg.hdr.cmd = CMD_CAN_TX;
 739        msg->msg.tx.net = priv->index;
 740        msg->msg.tx.dlc = cf->can_dlc;
 741        msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
 742
 743        if (cf->can_id & CAN_RTR_FLAG)
 744                msg->msg.tx.dlc |= ESD_RTR;
 745
 746        if (cf->can_id & CAN_EFF_FLAG)
 747                msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
 748
 749        for (i = 0; i < cf->can_dlc; i++)
 750                msg->msg.tx.data[i] = cf->data[i];
 751
 752        msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
 753
 754        for (i = 0; i < MAX_TX_URBS; i++) {
 755                if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
 756                        context = &priv->tx_contexts[i];
 757                        break;
 758                }
 759        }
 760
 761        /*
 762         * This may never happen.
 763         */
 764        if (!context) {
 765                netdev_warn(netdev, "couldn't find free context\n");
 766                ret = NETDEV_TX_BUSY;
 767                goto releasebuf;
 768        }
 769
 770        context->priv = priv;
 771        context->echo_index = i;
 772        context->dlc = cf->can_dlc;
 773
 774        /* hnd must not be 0 - MSB is stripped in txdone handling */
 775        msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
 776
 777        usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
 778                          msg->msg.hdr.len << 2,
 779                          esd_usb2_write_bulk_callback, context);
 780
 781        urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 782
 783        usb_anchor_urb(urb, &priv->tx_submitted);
 784
 785        can_put_echo_skb(skb, netdev, context->echo_index);
 786
 787        atomic_inc(&priv->active_tx_jobs);
 788
 789        /* Slow down tx path */
 790        if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
 791                netif_stop_queue(netdev);
 792
 793        err = usb_submit_urb(urb, GFP_ATOMIC);
 794        if (err) {
 795                can_free_echo_skb(netdev, context->echo_index);
 796
 797                atomic_dec(&priv->active_tx_jobs);
 798                usb_unanchor_urb(urb);
 799
 800                stats->tx_dropped++;
 801
 802                if (err == -ENODEV)
 803                        netif_device_detach(netdev);
 804                else
 805                        netdev_warn(netdev, "failed tx_urb %d\n", err);
 806
 807                goto releasebuf;
 808        }
 809
 810        netif_trans_update(netdev);
 811
 812        /*
 813         * Release our reference to this URB, the USB core will eventually free
 814         * it entirely.
 815         */
 816        usb_free_urb(urb);
 817
 818        return NETDEV_TX_OK;
 819
 820releasebuf:
 821        usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
 822
 823nobufmem:
 824        usb_free_urb(urb);
 825
 826nourbmem:
 827        return ret;
 828}
 829
 830static int esd_usb2_close(struct net_device *netdev)
 831{
 832        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 833        struct esd_usb2_msg *msg;
 834        int i;
 835
 836        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 837        if (!msg)
 838                return -ENOMEM;
 839
 840        /* Disable all IDs (see esd_usb2_start()) */
 841        msg->msg.hdr.cmd = CMD_IDADD;
 842        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 843        msg->msg.filter.net = priv->index;
 844        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 845        for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
 846                msg->msg.filter.mask[i] = 0;
 847        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 848                netdev_err(netdev, "sending idadd message failed\n");
 849
 850        /* set CAN controller to reset mode */
 851        msg->msg.hdr.len = 2;
 852        msg->msg.hdr.cmd = CMD_SETBAUD;
 853        msg->msg.setbaud.net = priv->index;
 854        msg->msg.setbaud.rsvd = 0;
 855        msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
 856        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 857                netdev_err(netdev, "sending setbaud message failed\n");
 858
 859        priv->can.state = CAN_STATE_STOPPED;
 860
 861        netif_stop_queue(netdev);
 862
 863        close_candev(netdev);
 864
 865        kfree(msg);
 866
 867        return 0;
 868}
 869
 870static const struct net_device_ops esd_usb2_netdev_ops = {
 871        .ndo_open = esd_usb2_open,
 872        .ndo_stop = esd_usb2_close,
 873        .ndo_start_xmit = esd_usb2_start_xmit,
 874        .ndo_change_mtu = can_change_mtu,
 875};
 876
 877static const struct can_bittiming_const esd_usb2_bittiming_const = {
 878        .name = "esd_usb2",
 879        .tseg1_min = ESD_USB2_TSEG1_MIN,
 880        .tseg1_max = ESD_USB2_TSEG1_MAX,
 881        .tseg2_min = ESD_USB2_TSEG2_MIN,
 882        .tseg2_max = ESD_USB2_TSEG2_MAX,
 883        .sjw_max = ESD_USB2_SJW_MAX,
 884        .brp_min = ESD_USB2_BRP_MIN,
 885        .brp_max = ESD_USB2_BRP_MAX,
 886        .brp_inc = ESD_USB2_BRP_INC,
 887};
 888
 889static int esd_usb2_set_bittiming(struct net_device *netdev)
 890{
 891        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 892        struct can_bittiming *bt = &priv->can.bittiming;
 893        struct esd_usb2_msg *msg;
 894        int err;
 895        u32 canbtr;
 896        int sjw_shift;
 897
 898        canbtr = ESD_USB2_UBR;
 899        if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 900                canbtr |= ESD_USB2_LOM;
 901
 902        canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
 903
 904        if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
 905            USB_CANUSBM_PRODUCT_ID)
 906                sjw_shift = ESD_USBM_SJW_SHIFT;
 907        else
 908                sjw_shift = ESD_USB2_SJW_SHIFT;
 909
 910        canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
 911                << sjw_shift;
 912        canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
 913                   & (ESD_USB2_TSEG1_MAX - 1))
 914                << ESD_USB2_TSEG1_SHIFT;
 915        canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
 916                << ESD_USB2_TSEG2_SHIFT;
 917        if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 918                canbtr |= ESD_USB2_3_SAMPLES;
 919
 920        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 921        if (!msg)
 922                return -ENOMEM;
 923
 924        msg->msg.hdr.len = 2;
 925        msg->msg.hdr.cmd = CMD_SETBAUD;
 926        msg->msg.setbaud.net = priv->index;
 927        msg->msg.setbaud.rsvd = 0;
 928        msg->msg.setbaud.baud = cpu_to_le32(canbtr);
 929
 930        netdev_info(netdev, "setting BTR=%#x\n", canbtr);
 931
 932        err = esd_usb2_send_msg(priv->usb2, msg);
 933
 934        kfree(msg);
 935        return err;
 936}
 937
 938static int esd_usb2_get_berr_counter(const struct net_device *netdev,
 939                                     struct can_berr_counter *bec)
 940{
 941        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 942
 943        bec->txerr = priv->bec.txerr;
 944        bec->rxerr = priv->bec.rxerr;
 945
 946        return 0;
 947}
 948
 949static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
 950{
 951        switch (mode) {
 952        case CAN_MODE_START:
 953                netif_wake_queue(netdev);
 954                break;
 955
 956        default:
 957                return -EOPNOTSUPP;
 958        }
 959
 960        return 0;
 961}
 962
 963static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
 964{
 965        struct esd_usb2 *dev = usb_get_intfdata(intf);
 966        struct net_device *netdev;
 967        struct esd_usb2_net_priv *priv;
 968        int err = 0;
 969        int i;
 970
 971        netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
 972        if (!netdev) {
 973                dev_err(&intf->dev, "couldn't alloc candev\n");
 974                err = -ENOMEM;
 975                goto done;
 976        }
 977
 978        priv = netdev_priv(netdev);
 979
 980        init_usb_anchor(&priv->tx_submitted);
 981        atomic_set(&priv->active_tx_jobs, 0);
 982
 983        for (i = 0; i < MAX_TX_URBS; i++)
 984                priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 985
 986        priv->usb2 = dev;
 987        priv->netdev = netdev;
 988        priv->index = index;
 989
 990        priv->can.state = CAN_STATE_STOPPED;
 991        priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
 992
 993        if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
 994            USB_CANUSBM_PRODUCT_ID)
 995                priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
 996        else {
 997                priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
 998                priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
 999        }
1000
1001        priv->can.bittiming_const = &esd_usb2_bittiming_const;
1002        priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1003        priv->can.do_set_mode = esd_usb2_set_mode;
1004        priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1005
1006        netdev->flags |= IFF_ECHO; /* we support local echo */
1007
1008        netdev->netdev_ops = &esd_usb2_netdev_ops;
1009
1010        SET_NETDEV_DEV(netdev, &intf->dev);
1011        netdev->dev_id = index;
1012
1013        err = register_candev(netdev);
1014        if (err) {
1015                dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1016                free_candev(netdev);
1017                err = -ENOMEM;
1018                goto done;
1019        }
1020
1021        dev->nets[index] = priv;
1022        netdev_info(netdev, "device %s registered\n", netdev->name);
1023
1024done:
1025        return err;
1026}
1027
1028/*
1029 * probe function for new USB2 devices
1030 *
1031 * check version information and number of available
1032 * CAN interfaces
1033 */
1034static int esd_usb2_probe(struct usb_interface *intf,
1035                         const struct usb_device_id *id)
1036{
1037        struct esd_usb2 *dev;
1038        struct esd_usb2_msg *msg;
1039        int i, err;
1040
1041        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1042        if (!dev) {
1043                err = -ENOMEM;
1044                goto done;
1045        }
1046
1047        dev->udev = interface_to_usbdev(intf);
1048
1049        init_usb_anchor(&dev->rx_submitted);
1050
1051        usb_set_intfdata(intf, dev);
1052
1053        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1054        if (!msg) {
1055                err = -ENOMEM;
1056                goto free_msg;
1057        }
1058
1059        /* query number of CAN interfaces (nets) */
1060        msg->msg.hdr.cmd = CMD_VERSION;
1061        msg->msg.hdr.len = 2;
1062        msg->msg.version.rsvd = 0;
1063        msg->msg.version.flags = 0;
1064        msg->msg.version.drv_version = 0;
1065
1066        err = esd_usb2_send_msg(dev, msg);
1067        if (err < 0) {
1068                dev_err(&intf->dev, "sending version message failed\n");
1069                goto free_msg;
1070        }
1071
1072        err = esd_usb2_wait_msg(dev, msg);
1073        if (err < 0) {
1074                dev_err(&intf->dev, "no version message answer\n");
1075                goto free_msg;
1076        }
1077
1078        dev->net_count = (int)msg->msg.version_reply.nets;
1079        dev->version = le32_to_cpu(msg->msg.version_reply.version);
1080
1081        if (device_create_file(&intf->dev, &dev_attr_firmware))
1082                dev_err(&intf->dev,
1083                        "Couldn't create device file for firmware\n");
1084
1085        if (device_create_file(&intf->dev, &dev_attr_hardware))
1086                dev_err(&intf->dev,
1087                        "Couldn't create device file for hardware\n");
1088
1089        if (device_create_file(&intf->dev, &dev_attr_nets))
1090                dev_err(&intf->dev,
1091                        "Couldn't create device file for nets\n");
1092
1093        /* do per device probing */
1094        for (i = 0; i < dev->net_count; i++)
1095                esd_usb2_probe_one_net(intf, i);
1096
1097free_msg:
1098        kfree(msg);
1099        if (err)
1100                kfree(dev);
1101done:
1102        return err;
1103}
1104
1105/*
1106 * called by the usb core when the device is removed from the system
1107 */
1108static void esd_usb2_disconnect(struct usb_interface *intf)
1109{
1110        struct esd_usb2 *dev = usb_get_intfdata(intf);
1111        struct net_device *netdev;
1112        int i;
1113
1114        device_remove_file(&intf->dev, &dev_attr_firmware);
1115        device_remove_file(&intf->dev, &dev_attr_hardware);
1116        device_remove_file(&intf->dev, &dev_attr_nets);
1117
1118        usb_set_intfdata(intf, NULL);
1119
1120        if (dev) {
1121                for (i = 0; i < dev->net_count; i++) {
1122                        if (dev->nets[i]) {
1123                                netdev = dev->nets[i]->netdev;
1124                                unregister_netdev(netdev);
1125                                free_candev(netdev);
1126                        }
1127                }
1128                unlink_all_urbs(dev);
1129                kfree(dev);
1130        }
1131}
1132
1133/* usb specific object needed to register this driver with the usb subsystem */
1134static struct usb_driver esd_usb2_driver = {
1135        .name = "esd_usb2",
1136        .probe = esd_usb2_probe,
1137        .disconnect = esd_usb2_disconnect,
1138        .id_table = esd_usb2_table,
1139};
1140
1141module_usb_driver(esd_usb2_driver);
1142