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/signal.h>
  20#include <linux/slab.h>
  21#include <linux/module.h>
  22#include <linux/netdevice.h>
  23#include <linux/usb.h>
  24
  25#include <linux/can.h>
  26#include <linux/can/dev.h>
  27#include <linux/can/error.h>
  28
  29MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
  30MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 and CAN-USB/Micro interfaces");
  31MODULE_LICENSE("GPL v2");
  32
  33/* Define these values to match your devices */
  34#define USB_ESDGMBH_VENDOR_ID   0x0ab4
  35#define USB_CANUSB2_PRODUCT_ID  0x0010
  36#define USB_CANUSBM_PRODUCT_ID  0x0011
  37
  38#define ESD_USB2_CAN_CLOCK      60000000
  39#define ESD_USBM_CAN_CLOCK      36000000
  40#define ESD_USB2_MAX_NETS       2
  41
  42/* USB2 commands */
  43#define CMD_VERSION             1 /* also used for VERSION_REPLY */
  44#define CMD_CAN_RX              2 /* device to host only */
  45#define CMD_CAN_TX              3 /* also used for TX_DONE */
  46#define CMD_SETBAUD             4 /* also used for SETBAUD_REPLY */
  47#define CMD_TS                  5 /* also used for TS_REPLY */
  48#define CMD_IDADD               6 /* also used for IDADD_REPLY */
  49
  50/* esd CAN message flags - dlc field */
  51#define ESD_RTR                 0x10
  52
  53/* esd CAN message flags - id field */
  54#define ESD_EXTID               0x20000000
  55#define ESD_EVENT               0x40000000
  56#define ESD_IDMASK              0x1fffffff
  57
  58/* esd CAN event ids used by this driver */
  59#define ESD_EV_CAN_ERROR_EXT    2
  60
  61/* baudrate message flags */
  62#define ESD_USB2_UBR            0x80000000
  63#define ESD_USB2_LOM            0x40000000
  64#define ESD_USB2_NO_BAUDRATE    0x7fffffff
  65#define ESD_USB2_TSEG1_MIN      1
  66#define ESD_USB2_TSEG1_MAX      16
  67#define ESD_USB2_TSEG1_SHIFT    16
  68#define ESD_USB2_TSEG2_MIN      1
  69#define ESD_USB2_TSEG2_MAX      8
  70#define ESD_USB2_TSEG2_SHIFT    20
  71#define ESD_USB2_SJW_MAX        4
  72#define ESD_USB2_SJW_SHIFT      14
  73#define ESD_USBM_SJW_SHIFT      24
  74#define ESD_USB2_BRP_MIN        1
  75#define ESD_USB2_BRP_MAX        1024
  76#define ESD_USB2_BRP_INC        1
  77#define ESD_USB2_3_SAMPLES      0x00800000
  78
  79/* esd IDADD message */
  80#define ESD_ID_ENABLE           0x80
  81#define ESD_MAX_ID_SEGMENT      64
  82
  83/* SJA1000 ECC register (emulated by usb2 firmware) */
  84#define SJA1000_ECC_SEG         0x1F
  85#define SJA1000_ECC_DIR         0x20
  86#define SJA1000_ECC_ERR         0x06
  87#define SJA1000_ECC_BIT         0x00
  88#define SJA1000_ECC_FORM        0x40
  89#define SJA1000_ECC_STUFF       0x80
  90#define SJA1000_ECC_MASK        0xc0
  91
  92/* esd bus state event codes */
  93#define ESD_BUSSTATE_MASK       0xc0
  94#define ESD_BUSSTATE_WARN       0x40
  95#define ESD_BUSSTATE_ERRPASSIVE 0x80
  96#define ESD_BUSSTATE_BUSOFF     0xc0
  97
  98#define RX_BUFFER_SIZE          1024
  99#define MAX_RX_URBS             4
 100#define MAX_TX_URBS             16 /* must be power of 2 */
 101
 102struct header_msg {
 103        u8 len; /* len is always the total message length in 32bit words */
 104        u8 cmd;
 105        u8 rsvd[2];
 106};
 107
 108struct version_msg {
 109        u8 len;
 110        u8 cmd;
 111        u8 rsvd;
 112        u8 flags;
 113        __le32 drv_version;
 114};
 115
 116struct version_reply_msg {
 117        u8 len;
 118        u8 cmd;
 119        u8 nets;
 120        u8 features;
 121        __le32 version;
 122        u8 name[16];
 123        __le32 rsvd;
 124        __le32 ts;
 125};
 126
 127struct rx_msg {
 128        u8 len;
 129        u8 cmd;
 130        u8 net;
 131        u8 dlc;
 132        __le32 ts;
 133        __le32 id; /* upper 3 bits contain flags */
 134        u8 data[8];
 135};
 136
 137struct tx_msg {
 138        u8 len;
 139        u8 cmd;
 140        u8 net;
 141        u8 dlc;
 142        u32 hnd;        /* opaque handle, not used by device */
 143        __le32 id; /* upper 3 bits contain flags */
 144        u8 data[8];
 145};
 146
 147struct tx_done_msg {
 148        u8 len;
 149        u8 cmd;
 150        u8 net;
 151        u8 status;
 152        u32 hnd;        /* opaque handle, not used by device */
 153        __le32 ts;
 154};
 155
 156struct id_filter_msg {
 157        u8 len;
 158        u8 cmd;
 159        u8 net;
 160        u8 option;
 161        __le32 mask[ESD_MAX_ID_SEGMENT + 1];
 162};
 163
 164struct set_baudrate_msg {
 165        u8 len;
 166        u8 cmd;
 167        u8 net;
 168        u8 rsvd;
 169        __le32 baud;
 170};
 171
 172/* Main message type used between library and application */
 173struct __attribute__ ((packed)) esd_usb2_msg {
 174        union {
 175                struct header_msg hdr;
 176                struct version_msg version;
 177                struct version_reply_msg version_reply;
 178                struct rx_msg rx;
 179                struct tx_msg tx;
 180                struct tx_done_msg txdone;
 181                struct set_baudrate_msg setbaud;
 182                struct id_filter_msg filter;
 183        } msg;
 184};
 185
 186static struct usb_device_id esd_usb2_table[] = {
 187        {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
 188        {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSBM_PRODUCT_ID)},
 189        {}
 190};
 191MODULE_DEVICE_TABLE(usb, esd_usb2_table);
 192
 193struct esd_usb2_net_priv;
 194
 195struct esd_tx_urb_context {
 196        struct esd_usb2_net_priv *priv;
 197        u32 echo_index;
 198        int dlc;
 199};
 200
 201struct esd_usb2 {
 202        struct usb_device *udev;
 203        struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
 204
 205        struct usb_anchor rx_submitted;
 206
 207        int net_count;
 208        u32 version;
 209        int rxinitdone;
 210};
 211
 212struct esd_usb2_net_priv {
 213        struct can_priv can; /* must be the first member */
 214
 215        atomic_t active_tx_jobs;
 216        struct usb_anchor tx_submitted;
 217        struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
 218
 219        struct esd_usb2 *usb2;
 220        struct net_device *netdev;
 221        int index;
 222        u8 old_state;
 223        struct can_berr_counter bec;
 224};
 225
 226static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
 227                              struct esd_usb2_msg *msg)
 228{
 229        struct net_device_stats *stats = &priv->netdev->stats;
 230        struct can_frame *cf;
 231        struct sk_buff *skb;
 232        u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
 233
 234        if (id == ESD_EV_CAN_ERROR_EXT) {
 235                u8 state = msg->msg.rx.data[0];
 236                u8 ecc = msg->msg.rx.data[1];
 237                u8 txerr = msg->msg.rx.data[2];
 238                u8 rxerr = msg->msg.rx.data[3];
 239
 240                skb = alloc_can_err_skb(priv->netdev, &cf);
 241                if (skb == NULL) {
 242                        stats->rx_dropped++;
 243                        return;
 244                }
 245
 246                if (state != priv->old_state) {
 247                        priv->old_state = state;
 248
 249                        switch (state & ESD_BUSSTATE_MASK) {
 250                        case ESD_BUSSTATE_BUSOFF:
 251                                priv->can.state = CAN_STATE_BUS_OFF;
 252                                cf->can_id |= CAN_ERR_BUSOFF;
 253                                priv->can.can_stats.bus_off++;
 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[3] = ecc & SJA1000_ECC_SEG;
 286                                break;
 287                        }
 288
 289                        /* Error occurred during transmission? */
 290                        if (!(ecc & SJA1000_ECC_DIR))
 291                                cf->data[2] |= CAN_ERR_PROT_TX;
 292
 293                        if (priv->can.state == CAN_STATE_ERROR_WARNING ||
 294                            priv->can.state == CAN_STATE_ERROR_PASSIVE) {
 295                                cf->data[1] = (txerr > rxerr) ?
 296                                        CAN_ERR_CRTL_TX_PASSIVE :
 297                                        CAN_ERR_CRTL_RX_PASSIVE;
 298                        }
 299                        cf->data[6] = txerr;
 300                        cf->data[7] = rxerr;
 301                }
 302
 303                priv->bec.txerr = txerr;
 304                priv->bec.rxerr = rxerr;
 305
 306                stats->rx_packets++;
 307                stats->rx_bytes += cf->can_dlc;
 308                netif_rx(skb);
 309        }
 310}
 311
 312static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
 313                                struct esd_usb2_msg *msg)
 314{
 315        struct net_device_stats *stats = &priv->netdev->stats;
 316        struct can_frame *cf;
 317        struct sk_buff *skb;
 318        int i;
 319        u32 id;
 320
 321        if (!netif_device_present(priv->netdev))
 322                return;
 323
 324        id = le32_to_cpu(msg->msg.rx.id);
 325
 326        if (id & ESD_EVENT) {
 327                esd_usb2_rx_event(priv, msg);
 328        } else {
 329                skb = alloc_can_skb(priv->netdev, &cf);
 330                if (skb == NULL) {
 331                        stats->rx_dropped++;
 332                        return;
 333                }
 334
 335                cf->can_id = id & ESD_IDMASK;
 336                cf->can_dlc = get_can_dlc(msg->msg.rx.dlc & ~ESD_RTR);
 337
 338                if (id & ESD_EXTID)
 339                        cf->can_id |= CAN_EFF_FLAG;
 340
 341                if (msg->msg.rx.dlc & ESD_RTR) {
 342                        cf->can_id |= CAN_RTR_FLAG;
 343                } else {
 344                        for (i = 0; i < cf->can_dlc; i++)
 345                                cf->data[i] = msg->msg.rx.data[i];
 346                }
 347
 348                stats->rx_packets++;
 349                stats->rx_bytes += cf->can_dlc;
 350                netif_rx(skb);
 351        }
 352
 353        return;
 354}
 355
 356static void esd_usb2_tx_done_msg(struct esd_usb2_net_priv *priv,
 357                                 struct esd_usb2_msg *msg)
 358{
 359        struct net_device_stats *stats = &priv->netdev->stats;
 360        struct net_device *netdev = priv->netdev;
 361        struct esd_tx_urb_context *context;
 362
 363        if (!netif_device_present(netdev))
 364                return;
 365
 366        context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
 367
 368        if (!msg->msg.txdone.status) {
 369                stats->tx_packets++;
 370                stats->tx_bytes += context->dlc;
 371                can_get_echo_skb(netdev, context->echo_index);
 372        } else {
 373                stats->tx_errors++;
 374                can_free_echo_skb(netdev, context->echo_index);
 375        }
 376
 377        /* Release context */
 378        context->echo_index = MAX_TX_URBS;
 379        atomic_dec(&priv->active_tx_jobs);
 380
 381        netif_wake_queue(netdev);
 382}
 383
 384static void esd_usb2_read_bulk_callback(struct urb *urb)
 385{
 386        struct esd_usb2 *dev = urb->context;
 387        int retval;
 388        int pos = 0;
 389        int i;
 390
 391        switch (urb->status) {
 392        case 0: /* success */
 393                break;
 394
 395        case -ENOENT:
 396        case -EPIPE:
 397        case -EPROTO:
 398        case -ESHUTDOWN:
 399                return;
 400
 401        default:
 402                dev_info(dev->udev->dev.parent,
 403                         "Rx URB aborted (%d)\n", urb->status);
 404                goto resubmit_urb;
 405        }
 406
 407        while (pos < urb->actual_length) {
 408                struct esd_usb2_msg *msg;
 409
 410                msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
 411
 412                switch (msg->msg.hdr.cmd) {
 413                case CMD_CAN_RX:
 414                        if (msg->msg.rx.net >= dev->net_count) {
 415                                dev_err(dev->udev->dev.parent, "format error\n");
 416                                break;
 417                        }
 418
 419                        esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
 420                        break;
 421
 422                case CMD_CAN_TX:
 423                        if (msg->msg.txdone.net >= dev->net_count) {
 424                                dev_err(dev->udev->dev.parent, "format error\n");
 425                                break;
 426                        }
 427
 428                        esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
 429                                             msg);
 430                        break;
 431                }
 432
 433                pos += msg->msg.hdr.len << 2;
 434
 435                if (pos > urb->actual_length) {
 436                        dev_err(dev->udev->dev.parent, "format error\n");
 437                        break;
 438                }
 439        }
 440
 441resubmit_urb:
 442        usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
 443                          urb->transfer_buffer, RX_BUFFER_SIZE,
 444                          esd_usb2_read_bulk_callback, dev);
 445
 446        retval = usb_submit_urb(urb, GFP_ATOMIC);
 447        if (retval == -ENODEV) {
 448                for (i = 0; i < dev->net_count; i++) {
 449                        if (dev->nets[i])
 450                                netif_device_detach(dev->nets[i]->netdev);
 451                }
 452        } else if (retval) {
 453                dev_err(dev->udev->dev.parent,
 454                        "failed resubmitting read bulk urb: %d\n", retval);
 455        }
 456
 457        return;
 458}
 459
 460/*
 461 * callback for bulk IN urb
 462 */
 463static void esd_usb2_write_bulk_callback(struct urb *urb)
 464{
 465        struct esd_tx_urb_context *context = urb->context;
 466        struct esd_usb2_net_priv *priv;
 467        struct net_device *netdev;
 468        size_t size = sizeof(struct esd_usb2_msg);
 469
 470        WARN_ON(!context);
 471
 472        priv = context->priv;
 473        netdev = priv->netdev;
 474
 475        /* free up our allocated buffer */
 476        usb_free_coherent(urb->dev, size,
 477                          urb->transfer_buffer, urb->transfer_dma);
 478
 479        if (!netif_device_present(netdev))
 480                return;
 481
 482        if (urb->status)
 483                netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
 484
 485        netif_trans_update(netdev);
 486}
 487
 488static ssize_t show_firmware(struct device *d,
 489                             struct device_attribute *attr, char *buf)
 490{
 491        struct usb_interface *intf = to_usb_interface(d);
 492        struct esd_usb2 *dev = usb_get_intfdata(intf);
 493
 494        return sprintf(buf, "%d.%d.%d\n",
 495                       (dev->version >> 12) & 0xf,
 496                       (dev->version >> 8) & 0xf,
 497                       dev->version & 0xff);
 498}
 499static DEVICE_ATTR(firmware, 0444, show_firmware, NULL);
 500
 501static ssize_t show_hardware(struct device *d,
 502                             struct device_attribute *attr, char *buf)
 503{
 504        struct usb_interface *intf = to_usb_interface(d);
 505        struct esd_usb2 *dev = usb_get_intfdata(intf);
 506
 507        return sprintf(buf, "%d.%d.%d\n",
 508                       (dev->version >> 28) & 0xf,
 509                       (dev->version >> 24) & 0xf,
 510                       (dev->version >> 16) & 0xff);
 511}
 512static DEVICE_ATTR(hardware, 0444, show_hardware, NULL);
 513
 514static ssize_t show_nets(struct device *d,
 515                         struct device_attribute *attr, char *buf)
 516{
 517        struct usb_interface *intf = to_usb_interface(d);
 518        struct esd_usb2 *dev = usb_get_intfdata(intf);
 519
 520        return sprintf(buf, "%d", dev->net_count);
 521}
 522static DEVICE_ATTR(nets, 0444, show_nets, NULL);
 523
 524static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
 525{
 526        int actual_length;
 527
 528        return usb_bulk_msg(dev->udev,
 529                            usb_sndbulkpipe(dev->udev, 2),
 530                            msg,
 531                            msg->msg.hdr.len << 2,
 532                            &actual_length,
 533                            1000);
 534}
 535
 536static int esd_usb2_wait_msg(struct esd_usb2 *dev,
 537                             struct esd_usb2_msg *msg)
 538{
 539        int actual_length;
 540
 541        return usb_bulk_msg(dev->udev,
 542                            usb_rcvbulkpipe(dev->udev, 1),
 543                            msg,
 544                            sizeof(*msg),
 545                            &actual_length,
 546                            1000);
 547}
 548
 549static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
 550{
 551        int i, err = 0;
 552
 553        if (dev->rxinitdone)
 554                return 0;
 555
 556        for (i = 0; i < MAX_RX_URBS; i++) {
 557                struct urb *urb = NULL;
 558                u8 *buf = NULL;
 559
 560                /* create a URB, and a buffer for it */
 561                urb = usb_alloc_urb(0, GFP_KERNEL);
 562                if (!urb) {
 563                        err = -ENOMEM;
 564                        break;
 565                }
 566
 567                buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
 568                                         &urb->transfer_dma);
 569                if (!buf) {
 570                        dev_warn(dev->udev->dev.parent,
 571                                 "No memory left for USB buffer\n");
 572                        err = -ENOMEM;
 573                        goto freeurb;
 574                }
 575
 576                usb_fill_bulk_urb(urb, dev->udev,
 577                                  usb_rcvbulkpipe(dev->udev, 1),
 578                                  buf, RX_BUFFER_SIZE,
 579                                  esd_usb2_read_bulk_callback, dev);
 580                urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 581                usb_anchor_urb(urb, &dev->rx_submitted);
 582
 583                err = usb_submit_urb(urb, GFP_KERNEL);
 584                if (err) {
 585                        usb_unanchor_urb(urb);
 586                        usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
 587                                          urb->transfer_dma);
 588                }
 589
 590freeurb:
 591                /* Drop reference, USB core will take care of freeing it */
 592                usb_free_urb(urb);
 593                if (err)
 594                        break;
 595        }
 596
 597        /* Did we submit any URBs */
 598        if (i == 0) {
 599                dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
 600                return err;
 601        }
 602
 603        /* Warn if we've couldn't transmit all the URBs */
 604        if (i < MAX_RX_URBS) {
 605                dev_warn(dev->udev->dev.parent,
 606                         "rx performance may be slow\n");
 607        }
 608
 609        dev->rxinitdone = 1;
 610        return 0;
 611}
 612
 613/*
 614 * Start interface
 615 */
 616static int esd_usb2_start(struct esd_usb2_net_priv *priv)
 617{
 618        struct esd_usb2 *dev = priv->usb2;
 619        struct net_device *netdev = priv->netdev;
 620        struct esd_usb2_msg *msg;
 621        int err, i;
 622
 623        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 624        if (!msg) {
 625                err = -ENOMEM;
 626                goto out;
 627        }
 628
 629        /*
 630         * Enable all IDs
 631         * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
 632         * Each bit represents one 11 bit CAN identifier. A set bit
 633         * enables reception of the corresponding CAN identifier. A cleared
 634         * bit disabled this identifier. An additional bitmask value
 635         * following the CAN 2.0A bits is used to enable reception of
 636         * extended CAN frames. Only the LSB of this final mask is checked
 637         * for the complete 29 bit ID range. The IDADD message also allows
 638         * filter configuration for an ID subset. In this case you can add
 639         * the number of the starting bitmask (0..64) to the filter.option
 640         * field followed by only some bitmasks.
 641         */
 642        msg->msg.hdr.cmd = CMD_IDADD;
 643        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 644        msg->msg.filter.net = priv->index;
 645        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 646        for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
 647                msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
 648        /* enable 29bit extended IDs */
 649        msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
 650
 651        err = esd_usb2_send_msg(dev, msg);
 652        if (err)
 653                goto out;
 654
 655        err = esd_usb2_setup_rx_urbs(dev);
 656        if (err)
 657                goto out;
 658
 659        priv->can.state = CAN_STATE_ERROR_ACTIVE;
 660
 661out:
 662        if (err == -ENODEV)
 663                netif_device_detach(netdev);
 664        if (err)
 665                netdev_err(netdev, "couldn't start device: %d\n", err);
 666
 667        kfree(msg);
 668        return err;
 669}
 670
 671static void unlink_all_urbs(struct esd_usb2 *dev)
 672{
 673        struct esd_usb2_net_priv *priv;
 674        int i, j;
 675
 676        usb_kill_anchored_urbs(&dev->rx_submitted);
 677        for (i = 0; i < dev->net_count; i++) {
 678                priv = dev->nets[i];
 679                if (priv) {
 680                        usb_kill_anchored_urbs(&priv->tx_submitted);
 681                        atomic_set(&priv->active_tx_jobs, 0);
 682
 683                        for (j = 0; j < MAX_TX_URBS; j++)
 684                                priv->tx_contexts[j].echo_index = MAX_TX_URBS;
 685                }
 686        }
 687}
 688
 689static int esd_usb2_open(struct net_device *netdev)
 690{
 691        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 692        int err;
 693
 694        /* common open */
 695        err = open_candev(netdev);
 696        if (err)
 697                return err;
 698
 699        /* finally start device */
 700        err = esd_usb2_start(priv);
 701        if (err) {
 702                netdev_warn(netdev, "couldn't start device: %d\n", err);
 703                close_candev(netdev);
 704                return err;
 705        }
 706
 707        netif_start_queue(netdev);
 708
 709        return 0;
 710}
 711
 712static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
 713                                      struct net_device *netdev)
 714{
 715        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 716        struct esd_usb2 *dev = priv->usb2;
 717        struct esd_tx_urb_context *context = NULL;
 718        struct net_device_stats *stats = &netdev->stats;
 719        struct can_frame *cf = (struct can_frame *)skb->data;
 720        struct esd_usb2_msg *msg;
 721        struct urb *urb;
 722        u8 *buf;
 723        int i, err;
 724        int ret = NETDEV_TX_OK;
 725        size_t size = sizeof(struct esd_usb2_msg);
 726
 727        if (can_dropped_invalid_skb(netdev, skb))
 728                return NETDEV_TX_OK;
 729
 730        /* create a URB, and a buffer for it, and copy the data to the URB */
 731        urb = usb_alloc_urb(0, GFP_ATOMIC);
 732        if (!urb) {
 733                stats->tx_dropped++;
 734                dev_kfree_skb(skb);
 735                goto nourbmem;
 736        }
 737
 738        buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
 739                                 &urb->transfer_dma);
 740        if (!buf) {
 741                netdev_err(netdev, "No memory left for USB buffer\n");
 742                stats->tx_dropped++;
 743                dev_kfree_skb(skb);
 744                goto nobufmem;
 745        }
 746
 747        msg = (struct esd_usb2_msg *)buf;
 748
 749        msg->msg.hdr.len = 3; /* minimal length */
 750        msg->msg.hdr.cmd = CMD_CAN_TX;
 751        msg->msg.tx.net = priv->index;
 752        msg->msg.tx.dlc = cf->can_dlc;
 753        msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
 754
 755        if (cf->can_id & CAN_RTR_FLAG)
 756                msg->msg.tx.dlc |= ESD_RTR;
 757
 758        if (cf->can_id & CAN_EFF_FLAG)
 759                msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
 760
 761        for (i = 0; i < cf->can_dlc; i++)
 762                msg->msg.tx.data[i] = cf->data[i];
 763
 764        msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
 765
 766        for (i = 0; i < MAX_TX_URBS; i++) {
 767                if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
 768                        context = &priv->tx_contexts[i];
 769                        break;
 770                }
 771        }
 772
 773        /*
 774         * This may never happen.
 775         */
 776        if (!context) {
 777                netdev_warn(netdev, "couldn't find free context\n");
 778                ret = NETDEV_TX_BUSY;
 779                goto releasebuf;
 780        }
 781
 782        context->priv = priv;
 783        context->echo_index = i;
 784        context->dlc = cf->can_dlc;
 785
 786        /* hnd must not be 0 - MSB is stripped in txdone handling */
 787        msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
 788
 789        usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
 790                          msg->msg.hdr.len << 2,
 791                          esd_usb2_write_bulk_callback, context);
 792
 793        urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 794
 795        usb_anchor_urb(urb, &priv->tx_submitted);
 796
 797        can_put_echo_skb(skb, netdev, context->echo_index);
 798
 799        atomic_inc(&priv->active_tx_jobs);
 800
 801        /* Slow down tx path */
 802        if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
 803                netif_stop_queue(netdev);
 804
 805        err = usb_submit_urb(urb, GFP_ATOMIC);
 806        if (err) {
 807                can_free_echo_skb(netdev, context->echo_index);
 808
 809                atomic_dec(&priv->active_tx_jobs);
 810                usb_unanchor_urb(urb);
 811
 812                stats->tx_dropped++;
 813
 814                if (err == -ENODEV)
 815                        netif_device_detach(netdev);
 816                else
 817                        netdev_warn(netdev, "failed tx_urb %d\n", err);
 818
 819                goto releasebuf;
 820        }
 821
 822        netif_trans_update(netdev);
 823
 824        /*
 825         * Release our reference to this URB, the USB core will eventually free
 826         * it entirely.
 827         */
 828        usb_free_urb(urb);
 829
 830        return NETDEV_TX_OK;
 831
 832releasebuf:
 833        usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
 834
 835nobufmem:
 836        usb_free_urb(urb);
 837
 838nourbmem:
 839        return ret;
 840}
 841
 842static int esd_usb2_close(struct net_device *netdev)
 843{
 844        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 845        struct esd_usb2_msg *msg;
 846        int i;
 847
 848        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 849        if (!msg)
 850                return -ENOMEM;
 851
 852        /* Disable all IDs (see esd_usb2_start()) */
 853        msg->msg.hdr.cmd = CMD_IDADD;
 854        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 855        msg->msg.filter.net = priv->index;
 856        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 857        for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
 858                msg->msg.filter.mask[i] = 0;
 859        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 860                netdev_err(netdev, "sending idadd message failed\n");
 861
 862        /* set CAN controller to reset mode */
 863        msg->msg.hdr.len = 2;
 864        msg->msg.hdr.cmd = CMD_SETBAUD;
 865        msg->msg.setbaud.net = priv->index;
 866        msg->msg.setbaud.rsvd = 0;
 867        msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
 868        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 869                netdev_err(netdev, "sending setbaud message failed\n");
 870
 871        priv->can.state = CAN_STATE_STOPPED;
 872
 873        netif_stop_queue(netdev);
 874
 875        close_candev(netdev);
 876
 877        kfree(msg);
 878
 879        return 0;
 880}
 881
 882static const struct net_device_ops esd_usb2_netdev_ops = {
 883        .ndo_open = esd_usb2_open,
 884        .ndo_stop = esd_usb2_close,
 885        .ndo_start_xmit = esd_usb2_start_xmit,
 886        .ndo_change_mtu = can_change_mtu,
 887};
 888
 889static const struct can_bittiming_const esd_usb2_bittiming_const = {
 890        .name = "esd_usb2",
 891        .tseg1_min = ESD_USB2_TSEG1_MIN,
 892        .tseg1_max = ESD_USB2_TSEG1_MAX,
 893        .tseg2_min = ESD_USB2_TSEG2_MIN,
 894        .tseg2_max = ESD_USB2_TSEG2_MAX,
 895        .sjw_max = ESD_USB2_SJW_MAX,
 896        .brp_min = ESD_USB2_BRP_MIN,
 897        .brp_max = ESD_USB2_BRP_MAX,
 898        .brp_inc = ESD_USB2_BRP_INC,
 899};
 900
 901static int esd_usb2_set_bittiming(struct net_device *netdev)
 902{
 903        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 904        struct can_bittiming *bt = &priv->can.bittiming;
 905        struct esd_usb2_msg *msg;
 906        int err;
 907        u32 canbtr;
 908        int sjw_shift;
 909
 910        canbtr = ESD_USB2_UBR;
 911        if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 912                canbtr |= ESD_USB2_LOM;
 913
 914        canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
 915
 916        if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
 917            USB_CANUSBM_PRODUCT_ID)
 918                sjw_shift = ESD_USBM_SJW_SHIFT;
 919        else
 920                sjw_shift = ESD_USB2_SJW_SHIFT;
 921
 922        canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
 923                << sjw_shift;
 924        canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
 925                   & (ESD_USB2_TSEG1_MAX - 1))
 926                << ESD_USB2_TSEG1_SHIFT;
 927        canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
 928                << ESD_USB2_TSEG2_SHIFT;
 929        if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 930                canbtr |= ESD_USB2_3_SAMPLES;
 931
 932        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 933        if (!msg)
 934                return -ENOMEM;
 935
 936        msg->msg.hdr.len = 2;
 937        msg->msg.hdr.cmd = CMD_SETBAUD;
 938        msg->msg.setbaud.net = priv->index;
 939        msg->msg.setbaud.rsvd = 0;
 940        msg->msg.setbaud.baud = cpu_to_le32(canbtr);
 941
 942        netdev_info(netdev, "setting BTR=%#x\n", canbtr);
 943
 944        err = esd_usb2_send_msg(priv->usb2, msg);
 945
 946        kfree(msg);
 947        return err;
 948}
 949
 950static int esd_usb2_get_berr_counter(const struct net_device *netdev,
 951                                     struct can_berr_counter *bec)
 952{
 953        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 954
 955        bec->txerr = priv->bec.txerr;
 956        bec->rxerr = priv->bec.rxerr;
 957
 958        return 0;
 959}
 960
 961static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
 962{
 963        switch (mode) {
 964        case CAN_MODE_START:
 965                netif_wake_queue(netdev);
 966                break;
 967
 968        default:
 969                return -EOPNOTSUPP;
 970        }
 971
 972        return 0;
 973}
 974
 975static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
 976{
 977        struct esd_usb2 *dev = usb_get_intfdata(intf);
 978        struct net_device *netdev;
 979        struct esd_usb2_net_priv *priv;
 980        int err = 0;
 981        int i;
 982
 983        netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
 984        if (!netdev) {
 985                dev_err(&intf->dev, "couldn't alloc candev\n");
 986                err = -ENOMEM;
 987                goto done;
 988        }
 989
 990        priv = netdev_priv(netdev);
 991
 992        init_usb_anchor(&priv->tx_submitted);
 993        atomic_set(&priv->active_tx_jobs, 0);
 994
 995        for (i = 0; i < MAX_TX_URBS; i++)
 996                priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 997
 998        priv->usb2 = dev;
 999        priv->netdev = netdev;
1000        priv->index = index;
1001
1002        priv->can.state = CAN_STATE_STOPPED;
1003        priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
1004
1005        if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1006            USB_CANUSBM_PRODUCT_ID)
1007                priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1008        else {
1009                priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1010                priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1011        }
1012
1013        priv->can.bittiming_const = &esd_usb2_bittiming_const;
1014        priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1015        priv->can.do_set_mode = esd_usb2_set_mode;
1016        priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1017
1018        netdev->flags |= IFF_ECHO; /* we support local echo */
1019
1020        netdev->netdev_ops = &esd_usb2_netdev_ops;
1021
1022        SET_NETDEV_DEV(netdev, &intf->dev);
1023        netdev->dev_id = index;
1024
1025        err = register_candev(netdev);
1026        if (err) {
1027                dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1028                free_candev(netdev);
1029                err = -ENOMEM;
1030                goto done;
1031        }
1032
1033        dev->nets[index] = priv;
1034        netdev_info(netdev, "device %s registered\n", netdev->name);
1035
1036done:
1037        return err;
1038}
1039
1040/*
1041 * probe function for new USB2 devices
1042 *
1043 * check version information and number of available
1044 * CAN interfaces
1045 */
1046static int esd_usb2_probe(struct usb_interface *intf,
1047                         const struct usb_device_id *id)
1048{
1049        struct esd_usb2 *dev;
1050        struct esd_usb2_msg *msg;
1051        int i, err;
1052
1053        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1054        if (!dev) {
1055                err = -ENOMEM;
1056                goto done;
1057        }
1058
1059        dev->udev = interface_to_usbdev(intf);
1060
1061        init_usb_anchor(&dev->rx_submitted);
1062
1063        usb_set_intfdata(intf, dev);
1064
1065        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1066        if (!msg) {
1067                err = -ENOMEM;
1068                goto free_msg;
1069        }
1070
1071        /* query number of CAN interfaces (nets) */
1072        msg->msg.hdr.cmd = CMD_VERSION;
1073        msg->msg.hdr.len = 2;
1074        msg->msg.version.rsvd = 0;
1075        msg->msg.version.flags = 0;
1076        msg->msg.version.drv_version = 0;
1077
1078        err = esd_usb2_send_msg(dev, msg);
1079        if (err < 0) {
1080                dev_err(&intf->dev, "sending version message failed\n");
1081                goto free_msg;
1082        }
1083
1084        err = esd_usb2_wait_msg(dev, msg);
1085        if (err < 0) {
1086                dev_err(&intf->dev, "no version message answer\n");
1087                goto free_msg;
1088        }
1089
1090        dev->net_count = (int)msg->msg.version_reply.nets;
1091        dev->version = le32_to_cpu(msg->msg.version_reply.version);
1092
1093        if (device_create_file(&intf->dev, &dev_attr_firmware))
1094                dev_err(&intf->dev,
1095                        "Couldn't create device file for firmware\n");
1096
1097        if (device_create_file(&intf->dev, &dev_attr_hardware))
1098                dev_err(&intf->dev,
1099                        "Couldn't create device file for hardware\n");
1100
1101        if (device_create_file(&intf->dev, &dev_attr_nets))
1102                dev_err(&intf->dev,
1103                        "Couldn't create device file for nets\n");
1104
1105        /* do per device probing */
1106        for (i = 0; i < dev->net_count; i++)
1107                esd_usb2_probe_one_net(intf, i);
1108
1109free_msg:
1110        kfree(msg);
1111        if (err)
1112                kfree(dev);
1113done:
1114        return err;
1115}
1116
1117/*
1118 * called by the usb core when the device is removed from the system
1119 */
1120static void esd_usb2_disconnect(struct usb_interface *intf)
1121{
1122        struct esd_usb2 *dev = usb_get_intfdata(intf);
1123        struct net_device *netdev;
1124        int i;
1125
1126        device_remove_file(&intf->dev, &dev_attr_firmware);
1127        device_remove_file(&intf->dev, &dev_attr_hardware);
1128        device_remove_file(&intf->dev, &dev_attr_nets);
1129
1130        usb_set_intfdata(intf, NULL);
1131
1132        if (dev) {
1133                for (i = 0; i < dev->net_count; i++) {
1134                        if (dev->nets[i]) {
1135                                netdev = dev->nets[i]->netdev;
1136                                unregister_netdev(netdev);
1137                                free_candev(netdev);
1138                        }
1139                }
1140                unlink_all_urbs(dev);
1141                kfree(dev);
1142        }
1143}
1144
1145/* usb specific object needed to register this driver with the usb subsystem */
1146static struct usb_driver esd_usb2_driver = {
1147        .name = "esd_usb2",
1148        .probe = esd_usb2_probe,
1149        .disconnect = esd_usb2_disconnect,
1150        .id_table = esd_usb2_table,
1151};
1152
1153module_usb_driver(esd_usb2_driver);
1154