linux/drivers/net/can/usb/esd_usb2.c
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   1/*
   2 * CAN driver for esd CAN-USB/2 and CAN-USB/Micro
   3 *
   4 * Copyright (C) 2010-2012 Matthias Fuchs <matthias.fuchs@esd.eu>, esd gmbh
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms of the GNU General Public License as published
   8 * by the Free Software Foundation; version 2 of the License.
   9 *
  10 * This program is distributed in the hope that it will be useful, but
  11 * WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 * General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License along
  16 * with this program; if not, write to the Free Software Foundation, Inc.,
  17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19#include <linux/init.h>
  20#include <linux/signal.h>
  21#include <linux/slab.h>
  22#include <linux/module.h>
  23#include <linux/netdevice.h>
  24#include <linux/usb.h>
  25
  26#include <linux/can.h>
  27#include <linux/can/dev.h>
  28#include <linux/can/error.h>
  29
  30MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
  31MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 and CAN-USB/Micro interfaces");
  32MODULE_LICENSE("GPL v2");
  33
  34/* Define these values to match your devices */
  35#define USB_ESDGMBH_VENDOR_ID   0x0ab4
  36#define USB_CANUSB2_PRODUCT_ID  0x0010
  37#define USB_CANUSBM_PRODUCT_ID  0x0011
  38
  39#define ESD_USB2_CAN_CLOCK      60000000
  40#define ESD_USBM_CAN_CLOCK      36000000
  41#define ESD_USB2_MAX_NETS       2
  42
  43/* USB2 commands */
  44#define CMD_VERSION             1 /* also used for VERSION_REPLY */
  45#define CMD_CAN_RX              2 /* device to host only */
  46#define CMD_CAN_TX              3 /* also used for TX_DONE */
  47#define CMD_SETBAUD             4 /* also used for SETBAUD_REPLY */
  48#define CMD_TS                  5 /* also used for TS_REPLY */
  49#define CMD_IDADD               6 /* also used for IDADD_REPLY */
  50
  51/* esd CAN message flags - dlc field */
  52#define ESD_RTR                 0x10
  53
  54/* esd CAN message flags - id field */
  55#define ESD_EXTID               0x20000000
  56#define ESD_EVENT               0x40000000
  57#define ESD_IDMASK              0x1fffffff
  58
  59/* esd CAN event ids used by this driver */
  60#define ESD_EV_CAN_ERROR_EXT    2
  61
  62/* baudrate message flags */
  63#define ESD_USB2_UBR            0x80000000
  64#define ESD_USB2_LOM            0x40000000
  65#define ESD_USB2_NO_BAUDRATE    0x7fffffff
  66#define ESD_USB2_TSEG1_MIN      1
  67#define ESD_USB2_TSEG1_MAX      16
  68#define ESD_USB2_TSEG1_SHIFT    16
  69#define ESD_USB2_TSEG2_MIN      1
  70#define ESD_USB2_TSEG2_MAX      8
  71#define ESD_USB2_TSEG2_SHIFT    20
  72#define ESD_USB2_SJW_MAX        4
  73#define ESD_USB2_SJW_SHIFT      14
  74#define ESD_USBM_SJW_SHIFT      24
  75#define ESD_USB2_BRP_MIN        1
  76#define ESD_USB2_BRP_MAX        1024
  77#define ESD_USB2_BRP_INC        1
  78#define ESD_USB2_3_SAMPLES      0x00800000
  79
  80/* esd IDADD message */
  81#define ESD_ID_ENABLE           0x80
  82#define ESD_MAX_ID_SEGMENT      64
  83
  84/* SJA1000 ECC register (emulated by usb2 firmware) */
  85#define SJA1000_ECC_SEG         0x1F
  86#define SJA1000_ECC_DIR         0x20
  87#define SJA1000_ECC_ERR         0x06
  88#define SJA1000_ECC_BIT         0x00
  89#define SJA1000_ECC_FORM        0x40
  90#define SJA1000_ECC_STUFF       0x80
  91#define SJA1000_ECC_MASK        0xc0
  92
  93/* esd bus state event codes */
  94#define ESD_BUSSTATE_MASK       0xc0
  95#define ESD_BUSSTATE_WARN       0x40
  96#define ESD_BUSSTATE_ERRPASSIVE 0x80
  97#define ESD_BUSSTATE_BUSOFF     0xc0
  98
  99#define RX_BUFFER_SIZE          1024
 100#define MAX_RX_URBS             4
 101#define MAX_TX_URBS             16 /* must be power of 2 */
 102
 103struct header_msg {
 104        u8 len; /* len is always the total message length in 32bit words */
 105        u8 cmd;
 106        u8 rsvd[2];
 107};
 108
 109struct version_msg {
 110        u8 len;
 111        u8 cmd;
 112        u8 rsvd;
 113        u8 flags;
 114        __le32 drv_version;
 115};
 116
 117struct version_reply_msg {
 118        u8 len;
 119        u8 cmd;
 120        u8 nets;
 121        u8 features;
 122        __le32 version;
 123        u8 name[16];
 124        __le32 rsvd;
 125        __le32 ts;
 126};
 127
 128struct rx_msg {
 129        u8 len;
 130        u8 cmd;
 131        u8 net;
 132        u8 dlc;
 133        __le32 ts;
 134        __le32 id; /* upper 3 bits contain flags */
 135        u8 data[8];
 136};
 137
 138struct tx_msg {
 139        u8 len;
 140        u8 cmd;
 141        u8 net;
 142        u8 dlc;
 143        __le32 hnd;
 144        __le32 id; /* upper 3 bits contain flags */
 145        u8 data[8];
 146};
 147
 148struct tx_done_msg {
 149        u8 len;
 150        u8 cmd;
 151        u8 net;
 152        u8 status;
 153        __le32 hnd;
 154        __le32 ts;
 155};
 156
 157struct id_filter_msg {
 158        u8 len;
 159        u8 cmd;
 160        u8 net;
 161        u8 option;
 162        __le32 mask[ESD_MAX_ID_SEGMENT + 1];
 163};
 164
 165struct set_baudrate_msg {
 166        u8 len;
 167        u8 cmd;
 168        u8 net;
 169        u8 rsvd;
 170        __le32 baud;
 171};
 172
 173/* Main message type used between library and application */
 174struct __attribute__ ((packed)) esd_usb2_msg {
 175        union {
 176                struct header_msg hdr;
 177                struct version_msg version;
 178                struct version_reply_msg version_reply;
 179                struct rx_msg rx;
 180                struct tx_msg tx;
 181                struct tx_done_msg txdone;
 182                struct set_baudrate_msg setbaud;
 183                struct id_filter_msg filter;
 184        } msg;
 185};
 186
 187static struct usb_device_id esd_usb2_table[] = {
 188        {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
 189        {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSBM_PRODUCT_ID)},
 190        {}
 191};
 192MODULE_DEVICE_TABLE(usb, esd_usb2_table);
 193
 194struct esd_usb2_net_priv;
 195
 196struct esd_tx_urb_context {
 197        struct esd_usb2_net_priv *priv;
 198        u32 echo_index;
 199        int dlc;
 200};
 201
 202struct esd_usb2 {
 203        struct usb_device *udev;
 204        struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
 205
 206        struct usb_anchor rx_submitted;
 207
 208        int net_count;
 209        u32 version;
 210        int rxinitdone;
 211};
 212
 213struct esd_usb2_net_priv {
 214        struct can_priv can; /* must be the first member */
 215
 216        atomic_t active_tx_jobs;
 217        struct usb_anchor tx_submitted;
 218        struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
 219
 220        struct esd_usb2 *usb2;
 221        struct net_device *netdev;
 222        int index;
 223        u8 old_state;
 224        struct can_berr_counter bec;
 225};
 226
 227static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
 228                              struct esd_usb2_msg *msg)
 229{
 230        struct net_device_stats *stats = &priv->netdev->stats;
 231        struct can_frame *cf;
 232        struct sk_buff *skb;
 233        u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
 234
 235        if (id == ESD_EV_CAN_ERROR_EXT) {
 236                u8 state = msg->msg.rx.data[0];
 237                u8 ecc = msg->msg.rx.data[1];
 238                u8 txerr = msg->msg.rx.data[2];
 239                u8 rxerr = msg->msg.rx.data[3];
 240
 241                skb = alloc_can_err_skb(priv->netdev, &cf);
 242                if (skb == NULL) {
 243                        stats->rx_dropped++;
 244                        return;
 245                }
 246
 247                if (state != priv->old_state) {
 248                        priv->old_state = state;
 249
 250                        switch (state & ESD_BUSSTATE_MASK) {
 251                        case ESD_BUSSTATE_BUSOFF:
 252                                priv->can.state = CAN_STATE_BUS_OFF;
 253                                cf->can_id |= CAN_ERR_BUSOFF;
 254                                can_bus_off(priv->netdev);
 255                                break;
 256                        case ESD_BUSSTATE_WARN:
 257                                priv->can.state = CAN_STATE_ERROR_WARNING;
 258                                priv->can.can_stats.error_warning++;
 259                                break;
 260                        case ESD_BUSSTATE_ERRPASSIVE:
 261                                priv->can.state = CAN_STATE_ERROR_PASSIVE;
 262                                priv->can.can_stats.error_passive++;
 263                                break;
 264                        default:
 265                                priv->can.state = CAN_STATE_ERROR_ACTIVE;
 266                                break;
 267                        }
 268                } else {
 269                        priv->can.can_stats.bus_error++;
 270                        stats->rx_errors++;
 271
 272                        cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 273
 274                        switch (ecc & SJA1000_ECC_MASK) {
 275                        case SJA1000_ECC_BIT:
 276                                cf->data[2] |= CAN_ERR_PROT_BIT;
 277                                break;
 278                        case SJA1000_ECC_FORM:
 279                                cf->data[2] |= CAN_ERR_PROT_FORM;
 280                                break;
 281                        case SJA1000_ECC_STUFF:
 282                                cf->data[2] |= CAN_ERR_PROT_STUFF;
 283                                break;
 284                        default:
 285                                cf->data[2] |= CAN_ERR_PROT_UNSPEC;
 286                                cf->data[3] = ecc & SJA1000_ECC_SEG;
 287                                break;
 288                        }
 289
 290                        /* Error occurred during transmission? */
 291                        if (!(ecc & SJA1000_ECC_DIR))
 292                                cf->data[2] |= CAN_ERR_PROT_TX;
 293
 294                        if (priv->can.state == CAN_STATE_ERROR_WARNING ||
 295                            priv->can.state == CAN_STATE_ERROR_PASSIVE) {
 296                                cf->data[1] = (txerr > rxerr) ?
 297                                        CAN_ERR_CRTL_TX_PASSIVE :
 298                                        CAN_ERR_CRTL_RX_PASSIVE;
 299                        }
 300                        cf->data[6] = txerr;
 301                        cf->data[7] = rxerr;
 302                }
 303
 304                netif_rx(skb);
 305
 306                priv->bec.txerr = txerr;
 307                priv->bec.rxerr = rxerr;
 308
 309                stats->rx_packets++;
 310                stats->rx_bytes += cf->can_dlc;
 311        }
 312}
 313
 314static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
 315                                struct esd_usb2_msg *msg)
 316{
 317        struct net_device_stats *stats = &priv->netdev->stats;
 318        struct can_frame *cf;
 319        struct sk_buff *skb;
 320        int i;
 321        u32 id;
 322
 323        if (!netif_device_present(priv->netdev))
 324                return;
 325
 326        id = le32_to_cpu(msg->msg.rx.id);
 327
 328        if (id & ESD_EVENT) {
 329                esd_usb2_rx_event(priv, msg);
 330        } else {
 331                skb = alloc_can_skb(priv->netdev, &cf);
 332                if (skb == NULL) {
 333                        stats->rx_dropped++;
 334                        return;
 335                }
 336
 337                cf->can_id = id & ESD_IDMASK;
 338                cf->can_dlc = get_can_dlc(msg->msg.rx.dlc);
 339
 340                if (id & ESD_EXTID)
 341                        cf->can_id |= CAN_EFF_FLAG;
 342
 343                if (msg->msg.rx.dlc & ESD_RTR) {
 344                        cf->can_id |= CAN_RTR_FLAG;
 345                } else {
 346                        for (i = 0; i < cf->can_dlc; i++)
 347                                cf->data[i] = msg->msg.rx.data[i];
 348                }
 349
 350                netif_rx(skb);
 351
 352                stats->rx_packets++;
 353                stats->rx_bytes += cf->can_dlc;
 354        }
 355
 356        return;
 357}
 358
 359static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
 360                                 struct esd_usb2_msg *msg)
 361{
 362        struct net_device_stats *stats = &priv->netdev->stats;
 363        struct net_device *netdev = priv->netdev;
 364        struct esd_tx_urb_context *context;
 365
 366        if (!netif_device_present(netdev))
 367                return;
 368
 369        context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
 370
 371        if (!msg->msg.txdone.status) {
 372                stats->tx_packets++;
 373                stats->tx_bytes += context->dlc;
 374                can_get_echo_skb(netdev, context->echo_index);
 375        } else {
 376                stats->tx_errors++;
 377                can_free_echo_skb(netdev, context->echo_index);
 378        }
 379
 380        /* Release context */
 381        context->echo_index = MAX_TX_URBS;
 382        atomic_dec(&priv->active_tx_jobs);
 383
 384        netif_wake_queue(netdev);
 385}
 386
 387static void esd_usb2_read_bulk_callback(struct urb *urb)
 388{
 389        struct esd_usb2 *dev = urb->context;
 390        int retval;
 391        int pos = 0;
 392        int i;
 393
 394        switch (urb->status) {
 395        case 0: /* success */
 396                break;
 397
 398        case -ENOENT:
 399        case -ESHUTDOWN:
 400                return;
 401
 402        default:
 403                dev_info(dev->udev->dev.parent,
 404                         "Rx URB aborted (%d)\n", urb->status);
 405                goto resubmit_urb;
 406        }
 407
 408        while (pos < urb->actual_length) {
 409                struct esd_usb2_msg *msg;
 410
 411                msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
 412
 413                switch (msg->msg.hdr.cmd) {
 414                case CMD_CAN_RX:
 415                        if (msg->msg.rx.net >= dev->net_count) {
 416                                dev_err(dev->udev->dev.parent, "format error\n");
 417                                break;
 418                        }
 419
 420                        esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
 421                        break;
 422
 423                case CMD_CAN_TX:
 424                        if (msg->msg.txdone.net >= dev->net_count) {
 425                                dev_err(dev->udev->dev.parent, "format error\n");
 426                                break;
 427                        }
 428
 429                        esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
 430                                             msg);
 431                        break;
 432                }
 433
 434                pos += msg->msg.hdr.len << 2;
 435
 436                if (pos > urb->actual_length) {
 437                        dev_err(dev->udev->dev.parent, "format error\n");
 438                        break;
 439                }
 440        }
 441
 442resubmit_urb:
 443        usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
 444                          urb->transfer_buffer, RX_BUFFER_SIZE,
 445                          esd_usb2_read_bulk_callback, dev);
 446
 447        retval = usb_submit_urb(urb, GFP_ATOMIC);
 448        if (retval == -ENODEV) {
 449                for (i = 0; i < dev->net_count; i++) {
 450                        if (dev->nets[i])
 451                                netif_device_detach(dev->nets[i]->netdev);
 452                }
 453        } else if (retval) {
 454                dev_err(dev->udev->dev.parent,
 455                        "failed resubmitting read bulk urb: %d\n", retval);
 456        }
 457
 458        return;
 459}
 460
 461/*
 462 * callback for bulk IN urb
 463 */
 464static void esd_usb2_write_bulk_callback(struct urb *urb)
 465{
 466        struct esd_tx_urb_context *context = urb->context;
 467        struct esd_usb2_net_priv *priv;
 468        struct esd_usb2 *dev;
 469        struct net_device *netdev;
 470        size_t size = sizeof(struct esd_usb2_msg);
 471
 472        WARN_ON(!context);
 473
 474        priv = context->priv;
 475        netdev = priv->netdev;
 476        dev = priv->usb2;
 477
 478        /* free up our allocated buffer */
 479        usb_free_coherent(urb->dev, size,
 480                          urb->transfer_buffer, urb->transfer_dma);
 481
 482        if (!netif_device_present(netdev))
 483                return;
 484
 485        if (urb->status)
 486                netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
 487
 488        netif_trans_update(netdev);
 489}
 490
 491static ssize_t show_firmware(struct device *d,
 492                             struct device_attribute *attr, char *buf)
 493{
 494        struct usb_interface *intf = to_usb_interface(d);
 495        struct esd_usb2 *dev = usb_get_intfdata(intf);
 496
 497        return sprintf(buf, "%d.%d.%d\n",
 498                       (dev->version >> 12) & 0xf,
 499                       (dev->version >> 8) & 0xf,
 500                       dev->version & 0xff);
 501}
 502static DEVICE_ATTR(firmware, S_IRUGO, show_firmware, NULL);
 503
 504static ssize_t show_hardware(struct device *d,
 505                             struct device_attribute *attr, char *buf)
 506{
 507        struct usb_interface *intf = to_usb_interface(d);
 508        struct esd_usb2 *dev = usb_get_intfdata(intf);
 509
 510        return sprintf(buf, "%d.%d.%d\n",
 511                       (dev->version >> 28) & 0xf,
 512                       (dev->version >> 24) & 0xf,
 513                       (dev->version >> 16) & 0xff);
 514}
 515static DEVICE_ATTR(hardware, S_IRUGO, show_hardware, NULL);
 516
 517static ssize_t show_nets(struct device *d,
 518                         struct device_attribute *attr, char *buf)
 519{
 520        struct usb_interface *intf = to_usb_interface(d);
 521        struct esd_usb2 *dev = usb_get_intfdata(intf);
 522
 523        return sprintf(buf, "%d", dev->net_count);
 524}
 525static DEVICE_ATTR(nets, S_IRUGO, show_nets, NULL);
 526
 527static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
 528{
 529        int actual_length;
 530
 531        return usb_bulk_msg(dev->udev,
 532                            usb_sndbulkpipe(dev->udev, 2),
 533                            msg,
 534                            msg->msg.hdr.len << 2,
 535                            &actual_length,
 536                            1000);
 537}
 538
 539static int esd_usb2_wait_msg(struct esd_usb2 *dev,
 540                             struct esd_usb2_msg *msg)
 541{
 542        int actual_length;
 543
 544        return usb_bulk_msg(dev->udev,
 545                            usb_rcvbulkpipe(dev->udev, 1),
 546                            msg,
 547                            sizeof(*msg),
 548                            &actual_length,
 549                            1000);
 550}
 551
 552static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
 553{
 554        int i, err = 0;
 555
 556        if (dev->rxinitdone)
 557                return 0;
 558
 559        for (i = 0; i < MAX_RX_URBS; i++) {
 560                struct urb *urb = NULL;
 561                u8 *buf = NULL;
 562
 563                /* create a URB, and a buffer for it */
 564                urb = usb_alloc_urb(0, GFP_KERNEL);
 565                if (!urb) {
 566                        dev_warn(dev->udev->dev.parent,
 567                                 "No memory left for URBs\n");
 568                        err = -ENOMEM;
 569                        break;
 570                }
 571
 572                buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
 573                                         &urb->transfer_dma);
 574                if (!buf) {
 575                        dev_warn(dev->udev->dev.parent,
 576                                 "No memory left for USB buffer\n");
 577                        err = -ENOMEM;
 578                        goto freeurb;
 579                }
 580
 581                usb_fill_bulk_urb(urb, dev->udev,
 582                                  usb_rcvbulkpipe(dev->udev, 1),
 583                                  buf, RX_BUFFER_SIZE,
 584                                  esd_usb2_read_bulk_callback, dev);
 585                urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 586                usb_anchor_urb(urb, &dev->rx_submitted);
 587
 588                err = usb_submit_urb(urb, GFP_KERNEL);
 589                if (err) {
 590                        usb_unanchor_urb(urb);
 591                        usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
 592                                          urb->transfer_dma);
 593                }
 594
 595freeurb:
 596                /* Drop reference, USB core will take care of freeing it */
 597                usb_free_urb(urb);
 598                if (err)
 599                        break;
 600        }
 601
 602        /* Did we submit any URBs */
 603        if (i == 0) {
 604                dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
 605                return err;
 606        }
 607
 608        /* Warn if we've couldn't transmit all the URBs */
 609        if (i < MAX_RX_URBS) {
 610                dev_warn(dev->udev->dev.parent,
 611                         "rx performance may be slow\n");
 612        }
 613
 614        dev->rxinitdone = 1;
 615        return 0;
 616}
 617
 618/*
 619 * Start interface
 620 */
 621static int esd_usb2_start(struct esd_usb2_net_priv *priv)
 622{
 623        struct esd_usb2 *dev = priv->usb2;
 624        struct net_device *netdev = priv->netdev;
 625        struct esd_usb2_msg *msg;
 626        int err, i;
 627
 628        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 629        if (!msg) {
 630                err = -ENOMEM;
 631                goto out;
 632        }
 633
 634        /*
 635         * Enable all IDs
 636         * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
 637         * Each bit represents one 11 bit CAN identifier. A set bit
 638         * enables reception of the corresponding CAN identifier. A cleared
 639         * bit disabled this identifier. An additional bitmask value
 640         * following the CAN 2.0A bits is used to enable reception of
 641         * extended CAN frames. Only the LSB of this final mask is checked
 642         * for the complete 29 bit ID range. The IDADD message also allows
 643         * filter configuration for an ID subset. In this case you can add
 644         * the number of the starting bitmask (0..64) to the filter.option
 645         * field followed by only some bitmasks.
 646         */
 647        msg->msg.hdr.cmd = CMD_IDADD;
 648        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 649        msg->msg.filter.net = priv->index;
 650        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 651        for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
 652                msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
 653        /* enable 29bit extended IDs */
 654        msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
 655
 656        err = esd_usb2_send_msg(dev, msg);
 657        if (err)
 658                goto out;
 659
 660        err = esd_usb2_setup_rx_urbs(dev);
 661        if (err)
 662                goto out;
 663
 664        priv->can.state = CAN_STATE_ERROR_ACTIVE;
 665
 666out:
 667        if (err == -ENODEV)
 668                netif_device_detach(netdev);
 669        if (err)
 670                netdev_err(netdev, "couldn't start device: %d\n", err);
 671
 672        kfree(msg);
 673        return err;
 674}
 675
 676static void unlink_all_urbs(struct esd_usb2 *dev)
 677{
 678        struct esd_usb2_net_priv *priv;
 679        int i, j;
 680
 681        usb_kill_anchored_urbs(&dev->rx_submitted);
 682        for (i = 0; i < dev->net_count; i++) {
 683                priv = dev->nets[i];
 684                if (priv) {
 685                        usb_kill_anchored_urbs(&priv->tx_submitted);
 686                        atomic_set(&priv->active_tx_jobs, 0);
 687
 688                        for (j = 0; j < MAX_TX_URBS; j++)
 689                                priv->tx_contexts[j].echo_index = MAX_TX_URBS;
 690                }
 691        }
 692}
 693
 694static int esd_usb2_open(struct net_device *netdev)
 695{
 696        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 697        int err;
 698
 699        /* common open */
 700        err = open_candev(netdev);
 701        if (err)
 702                return err;
 703
 704        /* finally start device */
 705        err = esd_usb2_start(priv);
 706        if (err) {
 707                netdev_warn(netdev, "couldn't start device: %d\n", err);
 708                close_candev(netdev);
 709                return err;
 710        }
 711
 712        netif_start_queue(netdev);
 713
 714        return 0;
 715}
 716
 717static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
 718                                      struct net_device *netdev)
 719{
 720        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 721        struct esd_usb2 *dev = priv->usb2;
 722        struct esd_tx_urb_context *context = NULL;
 723        struct net_device_stats *stats = &netdev->stats;
 724        struct can_frame *cf = (struct can_frame *)skb->data;
 725        struct esd_usb2_msg *msg;
 726        struct urb *urb;
 727        u8 *buf;
 728        int i, err;
 729        int ret = NETDEV_TX_OK;
 730        size_t size = sizeof(struct esd_usb2_msg);
 731
 732        if (can_dropped_invalid_skb(netdev, skb))
 733                return NETDEV_TX_OK;
 734
 735        /* create a URB, and a buffer for it, and copy the data to the URB */
 736        urb = usb_alloc_urb(0, GFP_ATOMIC);
 737        if (!urb) {
 738                netdev_err(netdev, "No memory left for URBs\n");
 739                stats->tx_dropped++;
 740                dev_kfree_skb(skb);
 741                goto nourbmem;
 742        }
 743
 744        buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
 745                                 &urb->transfer_dma);
 746        if (!buf) {
 747                netdev_err(netdev, "No memory left for USB buffer\n");
 748                stats->tx_dropped++;
 749                dev_kfree_skb(skb);
 750                goto nobufmem;
 751        }
 752
 753        msg = (struct esd_usb2_msg *)buf;
 754
 755        msg->msg.hdr.len = 3; /* minimal length */
 756        msg->msg.hdr.cmd = CMD_CAN_TX;
 757        msg->msg.tx.net = priv->index;
 758        msg->msg.tx.dlc = cf->can_dlc;
 759        msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
 760
 761        if (cf->can_id & CAN_RTR_FLAG)
 762                msg->msg.tx.dlc |= ESD_RTR;
 763
 764        if (cf->can_id & CAN_EFF_FLAG)
 765                msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
 766
 767        for (i = 0; i < cf->can_dlc; i++)
 768                msg->msg.tx.data[i] = cf->data[i];
 769
 770        msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
 771
 772        for (i = 0; i < MAX_TX_URBS; i++) {
 773                if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
 774                        context = &priv->tx_contexts[i];
 775                        break;
 776                }
 777        }
 778
 779        /*
 780         * This may never happen.
 781         */
 782        if (!context) {
 783                netdev_warn(netdev, "couldn't find free context\n");
 784                ret = NETDEV_TX_BUSY;
 785                goto releasebuf;
 786        }
 787
 788        context->priv = priv;
 789        context->echo_index = i;
 790        context->dlc = cf->can_dlc;
 791
 792        /* hnd must not be 0 - MSB is stripped in txdone handling */
 793        msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
 794
 795        usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
 796                          msg->msg.hdr.len << 2,
 797                          esd_usb2_write_bulk_callback, context);
 798
 799        urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 800
 801        usb_anchor_urb(urb, &priv->tx_submitted);
 802
 803        can_put_echo_skb(skb, netdev, context->echo_index);
 804
 805        atomic_inc(&priv->active_tx_jobs);
 806
 807        /* Slow down tx path */
 808        if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
 809                netif_stop_queue(netdev);
 810
 811        err = usb_submit_urb(urb, GFP_ATOMIC);
 812        if (err) {
 813                can_free_echo_skb(netdev, context->echo_index);
 814
 815                atomic_dec(&priv->active_tx_jobs);
 816                usb_unanchor_urb(urb);
 817
 818                stats->tx_dropped++;
 819
 820                if (err == -ENODEV)
 821                        netif_device_detach(netdev);
 822                else
 823                        netdev_warn(netdev, "failed tx_urb %d\n", err);
 824
 825                goto releasebuf;
 826        }
 827
 828        netif_trans_update(netdev);
 829
 830        /*
 831         * Release our reference to this URB, the USB core will eventually free
 832         * it entirely.
 833         */
 834        usb_free_urb(urb);
 835
 836        return NETDEV_TX_OK;
 837
 838releasebuf:
 839        usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
 840
 841nobufmem:
 842        usb_free_urb(urb);
 843
 844nourbmem:
 845        return ret;
 846}
 847
 848static int esd_usb2_close(struct net_device *netdev)
 849{
 850        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 851        struct esd_usb2_msg *msg;
 852        int i;
 853
 854        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 855        if (!msg)
 856                return -ENOMEM;
 857
 858        /* Disable all IDs (see esd_usb2_start()) */
 859        msg->msg.hdr.cmd = CMD_IDADD;
 860        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 861        msg->msg.filter.net = priv->index;
 862        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 863        for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
 864                msg->msg.filter.mask[i] = 0;
 865        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 866                netdev_err(netdev, "sending idadd message failed\n");
 867
 868        /* set CAN controller to reset mode */
 869        msg->msg.hdr.len = 2;
 870        msg->msg.hdr.cmd = CMD_SETBAUD;
 871        msg->msg.setbaud.net = priv->index;
 872        msg->msg.setbaud.rsvd = 0;
 873        msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
 874        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 875                netdev_err(netdev, "sending setbaud message failed\n");
 876
 877        priv->can.state = CAN_STATE_STOPPED;
 878
 879        netif_stop_queue(netdev);
 880
 881        close_candev(netdev);
 882
 883        kfree(msg);
 884
 885        return 0;
 886}
 887
 888static const struct net_device_ops esd_usb2_netdev_ops = {
 889        .ndo_open = esd_usb2_open,
 890        .ndo_stop = esd_usb2_close,
 891        .ndo_start_xmit = esd_usb2_start_xmit,
 892};
 893
 894static const struct can_bittiming_const esd_usb2_bittiming_const = {
 895        .name = "esd_usb2",
 896        .tseg1_min = ESD_USB2_TSEG1_MIN,
 897        .tseg1_max = ESD_USB2_TSEG1_MAX,
 898        .tseg2_min = ESD_USB2_TSEG2_MIN,
 899        .tseg2_max = ESD_USB2_TSEG2_MAX,
 900        .sjw_max = ESD_USB2_SJW_MAX,
 901        .brp_min = ESD_USB2_BRP_MIN,
 902        .brp_max = ESD_USB2_BRP_MAX,
 903        .brp_inc = ESD_USB2_BRP_INC,
 904};
 905
 906static int esd_usb2_set_bittiming(struct net_device *netdev)
 907{
 908        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 909        struct can_bittiming *bt = &priv->can.bittiming;
 910        struct esd_usb2_msg *msg;
 911        int err;
 912        u32 canbtr;
 913        int sjw_shift;
 914
 915        canbtr = ESD_USB2_UBR;
 916        if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 917                canbtr |= ESD_USB2_LOM;
 918
 919        canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
 920
 921        if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
 922            USB_CANUSBM_PRODUCT_ID)
 923                sjw_shift = ESD_USBM_SJW_SHIFT;
 924        else
 925                sjw_shift = ESD_USB2_SJW_SHIFT;
 926
 927        canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
 928                << sjw_shift;
 929        canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
 930                   & (ESD_USB2_TSEG1_MAX - 1))
 931                << ESD_USB2_TSEG1_SHIFT;
 932        canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
 933                << ESD_USB2_TSEG2_SHIFT;
 934        if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 935                canbtr |= ESD_USB2_3_SAMPLES;
 936
 937        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 938        if (!msg)
 939                return -ENOMEM;
 940
 941        msg->msg.hdr.len = 2;
 942        msg->msg.hdr.cmd = CMD_SETBAUD;
 943        msg->msg.setbaud.net = priv->index;
 944        msg->msg.setbaud.rsvd = 0;
 945        msg->msg.setbaud.baud = cpu_to_le32(canbtr);
 946
 947        netdev_info(netdev, "setting BTR=%#x\n", canbtr);
 948
 949        err = esd_usb2_send_msg(priv->usb2, msg);
 950
 951        kfree(msg);
 952        return err;
 953}
 954
 955static int esd_usb2_get_berr_counter(const struct net_device *netdev,
 956                                     struct can_berr_counter *bec)
 957{
 958        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 959
 960        bec->txerr = priv->bec.txerr;
 961        bec->rxerr = priv->bec.rxerr;
 962
 963        return 0;
 964}
 965
 966static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
 967{
 968        switch (mode) {
 969        case CAN_MODE_START:
 970                netif_wake_queue(netdev);
 971                break;
 972
 973        default:
 974                return -EOPNOTSUPP;
 975        }
 976
 977        return 0;
 978}
 979
 980static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
 981{
 982        struct esd_usb2 *dev = usb_get_intfdata(intf);
 983        struct net_device *netdev;
 984        struct esd_usb2_net_priv *priv;
 985        int err = 0;
 986        int i;
 987
 988        netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
 989        if (!netdev) {
 990                dev_err(&intf->dev, "couldn't alloc candev\n");
 991                err = -ENOMEM;
 992                goto done;
 993        }
 994
 995        priv = netdev_priv(netdev);
 996
 997        init_usb_anchor(&priv->tx_submitted);
 998        atomic_set(&priv->active_tx_jobs, 0);
 999
1000        for (i = 0; i < MAX_TX_URBS; i++)
1001                priv->tx_contexts[i].echo_index = MAX_TX_URBS;
1002
1003        priv->usb2 = dev;
1004        priv->netdev = netdev;
1005        priv->index = index;
1006
1007        priv->can.state = CAN_STATE_STOPPED;
1008        priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
1009
1010        if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1011            USB_CANUSBM_PRODUCT_ID)
1012                priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1013        else {
1014                priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1015                priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1016        }
1017
1018        priv->can.bittiming_const = &esd_usb2_bittiming_const;
1019        priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1020        priv->can.do_set_mode = esd_usb2_set_mode;
1021        priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1022
1023        netdev->flags |= IFF_ECHO; /* we support local echo */
1024
1025        netdev->netdev_ops = &esd_usb2_netdev_ops;
1026
1027        SET_NETDEV_DEV(netdev, &intf->dev);
1028
1029        err = register_candev(netdev);
1030        if (err) {
1031                dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1032                free_candev(netdev);
1033                err = -ENOMEM;
1034                goto done;
1035        }
1036
1037        dev->nets[index] = priv;
1038        netdev_info(netdev, "device %s registered\n", netdev->name);
1039
1040done:
1041        return err;
1042}
1043
1044/*
1045 * probe function for new USB2 devices
1046 *
1047 * check version information and number of available
1048 * CAN interfaces
1049 */
1050static int esd_usb2_probe(struct usb_interface *intf,
1051                         const struct usb_device_id *id)
1052{
1053        struct esd_usb2 *dev;
1054        struct esd_usb2_msg *msg;
1055        int i, err;
1056
1057        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1058        if (!dev) {
1059                err = -ENOMEM;
1060                goto done;
1061        }
1062
1063        dev->udev = interface_to_usbdev(intf);
1064
1065        init_usb_anchor(&dev->rx_submitted);
1066
1067        usb_set_intfdata(intf, dev);
1068
1069        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1070        if (!msg) {
1071                err = -ENOMEM;
1072                goto free_msg;
1073        }
1074
1075        /* query number of CAN interfaces (nets) */
1076        msg->msg.hdr.cmd = CMD_VERSION;
1077        msg->msg.hdr.len = 2;
1078        msg->msg.version.rsvd = 0;
1079        msg->msg.version.flags = 0;
1080        msg->msg.version.drv_version = 0;
1081
1082        err = esd_usb2_send_msg(dev, msg);
1083        if (err < 0) {
1084                dev_err(&intf->dev, "sending version message failed\n");
1085                goto free_msg;
1086        }
1087
1088        err = esd_usb2_wait_msg(dev, msg);
1089        if (err < 0) {
1090                dev_err(&intf->dev, "no version message answer\n");
1091                goto free_msg;
1092        }
1093
1094        dev->net_count = (int)msg->msg.version_reply.nets;
1095        dev->version = le32_to_cpu(msg->msg.version_reply.version);
1096
1097        if (device_create_file(&intf->dev, &dev_attr_firmware))
1098                dev_err(&intf->dev,
1099                        "Couldn't create device file for firmware\n");
1100
1101        if (device_create_file(&intf->dev, &dev_attr_hardware))
1102                dev_err(&intf->dev,
1103                        "Couldn't create device file for hardware\n");
1104
1105        if (device_create_file(&intf->dev, &dev_attr_nets))
1106                dev_err(&intf->dev,
1107                        "Couldn't create device file for nets\n");
1108
1109        /* do per device probing */
1110        for (i = 0; i < dev->net_count; i++)
1111                esd_usb2_probe_one_net(intf, i);
1112
1113free_msg:
1114        kfree(msg);
1115        if (err)
1116                kfree(dev);
1117done:
1118        return err;
1119}
1120
1121/*
1122 * called by the usb core when the device is removed from the system
1123 */
1124static void esd_usb2_disconnect(struct usb_interface *intf)
1125{
1126        struct esd_usb2 *dev = usb_get_intfdata(intf);
1127        struct net_device *netdev;
1128        int i;
1129
1130        device_remove_file(&intf->dev, &dev_attr_firmware);
1131        device_remove_file(&intf->dev, &dev_attr_hardware);
1132        device_remove_file(&intf->dev, &dev_attr_nets);
1133
1134        usb_set_intfdata(intf, NULL);
1135
1136        if (dev) {
1137                for (i = 0; i < dev->net_count; i++) {
1138                        if (dev->nets[i]) {
1139                                netdev = dev->nets[i]->netdev;
1140                                unregister_netdev(netdev);
1141                                free_candev(netdev);
1142                        }
1143                }
1144                unlink_all_urbs(dev);
1145                kfree(dev);
1146        }
1147}
1148
1149/* usb specific object needed to register this driver with the usb subsystem */
1150static struct usb_driver esd_usb2_driver = {
1151        .name = "esd_usb2",
1152        .probe = esd_usb2_probe,
1153        .disconnect = esd_usb2_disconnect,
1154        .id_table = esd_usb2_table,
1155};
1156
1157module_usb_driver(esd_usb2_driver);
1158