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);
 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 -ESHUTDOWN:
 397                return;
 398
 399        default:
 400                dev_info(dev->udev->dev.parent,
 401                         "Rx URB aborted (%d)\n", urb->status);
 402                goto resubmit_urb;
 403        }
 404
 405        while (pos < urb->actual_length) {
 406                struct esd_usb2_msg *msg;
 407
 408                msg = (struct esd_usb2_msg *)(urb->transfer_buffer + pos);
 409
 410                switch (msg->msg.hdr.cmd) {
 411                case CMD_CAN_RX:
 412                        if (msg->msg.rx.net >= dev->net_count) {
 413                                dev_err(dev->udev->dev.parent, "format error\n");
 414                                break;
 415                        }
 416
 417                        esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
 418                        break;
 419
 420                case CMD_CAN_TX:
 421                        if (msg->msg.txdone.net >= dev->net_count) {
 422                                dev_err(dev->udev->dev.parent, "format error\n");
 423                                break;
 424                        }
 425
 426                        esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
 427                                             msg);
 428                        break;
 429                }
 430
 431                pos += msg->msg.hdr.len << 2;
 432
 433                if (pos > urb->actual_length) {
 434                        dev_err(dev->udev->dev.parent, "format error\n");
 435                        break;
 436                }
 437        }
 438
 439resubmit_urb:
 440        usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
 441                          urb->transfer_buffer, RX_BUFFER_SIZE,
 442                          esd_usb2_read_bulk_callback, dev);
 443
 444        retval = usb_submit_urb(urb, GFP_ATOMIC);
 445        if (retval == -ENODEV) {
 446                for (i = 0; i < dev->net_count; i++) {
 447                        if (dev->nets[i])
 448                                netif_device_detach(dev->nets[i]->netdev);
 449                }
 450        } else if (retval) {
 451                dev_err(dev->udev->dev.parent,
 452                        "failed resubmitting read bulk urb: %d\n", retval);
 453        }
 454
 455        return;
 456}
 457
 458/*
 459 * callback for bulk IN urb
 460 */
 461static void esd_usb2_write_bulk_callback(struct urb *urb)
 462{
 463        struct esd_tx_urb_context *context = urb->context;
 464        struct esd_usb2_net_priv *priv;
 465        struct net_device *netdev;
 466        size_t size = sizeof(struct esd_usb2_msg);
 467
 468        WARN_ON(!context);
 469
 470        priv = context->priv;
 471        netdev = priv->netdev;
 472
 473        /* free up our allocated buffer */
 474        usb_free_coherent(urb->dev, size,
 475                          urb->transfer_buffer, urb->transfer_dma);
 476
 477        if (!netif_device_present(netdev))
 478                return;
 479
 480        if (urb->status)
 481                netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
 482
 483        netif_trans_update(netdev);
 484}
 485
 486static ssize_t show_firmware(struct device *d,
 487                             struct device_attribute *attr, char *buf)
 488{
 489        struct usb_interface *intf = to_usb_interface(d);
 490        struct esd_usb2 *dev = usb_get_intfdata(intf);
 491
 492        return sprintf(buf, "%d.%d.%d\n",
 493                       (dev->version >> 12) & 0xf,
 494                       (dev->version >> 8) & 0xf,
 495                       dev->version & 0xff);
 496}
 497static DEVICE_ATTR(firmware, S_IRUGO, show_firmware, NULL);
 498
 499static ssize_t show_hardware(struct device *d,
 500                             struct device_attribute *attr, char *buf)
 501{
 502        struct usb_interface *intf = to_usb_interface(d);
 503        struct esd_usb2 *dev = usb_get_intfdata(intf);
 504
 505        return sprintf(buf, "%d.%d.%d\n",
 506                       (dev->version >> 28) & 0xf,
 507                       (dev->version >> 24) & 0xf,
 508                       (dev->version >> 16) & 0xff);
 509}
 510static DEVICE_ATTR(hardware, S_IRUGO, show_hardware, NULL);
 511
 512static ssize_t show_nets(struct device *d,
 513                         struct device_attribute *attr, char *buf)
 514{
 515        struct usb_interface *intf = to_usb_interface(d);
 516        struct esd_usb2 *dev = usb_get_intfdata(intf);
 517
 518        return sprintf(buf, "%d", dev->net_count);
 519}
 520static DEVICE_ATTR(nets, S_IRUGO, show_nets, NULL);
 521
 522static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
 523{
 524        int actual_length;
 525
 526        return usb_bulk_msg(dev->udev,
 527                            usb_sndbulkpipe(dev->udev, 2),
 528                            msg,
 529                            msg->msg.hdr.len << 2,
 530                            &actual_length,
 531                            1000);
 532}
 533
 534static int esd_usb2_wait_msg(struct esd_usb2 *dev,
 535                             struct esd_usb2_msg *msg)
 536{
 537        int actual_length;
 538
 539        return usb_bulk_msg(dev->udev,
 540                            usb_rcvbulkpipe(dev->udev, 1),
 541                            msg,
 542                            sizeof(*msg),
 543                            &actual_length,
 544                            1000);
 545}
 546
 547static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
 548{
 549        int i, err = 0;
 550
 551        if (dev->rxinitdone)
 552                return 0;
 553
 554        for (i = 0; i < MAX_RX_URBS; i++) {
 555                struct urb *urb = NULL;
 556                u8 *buf = NULL;
 557
 558                /* create a URB, and a buffer for it */
 559                urb = usb_alloc_urb(0, GFP_KERNEL);
 560                if (!urb) {
 561                        err = -ENOMEM;
 562                        break;
 563                }
 564
 565                buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
 566                                         &urb->transfer_dma);
 567                if (!buf) {
 568                        dev_warn(dev->udev->dev.parent,
 569                                 "No memory left for USB buffer\n");
 570                        err = -ENOMEM;
 571                        goto freeurb;
 572                }
 573
 574                usb_fill_bulk_urb(urb, dev->udev,
 575                                  usb_rcvbulkpipe(dev->udev, 1),
 576                                  buf, RX_BUFFER_SIZE,
 577                                  esd_usb2_read_bulk_callback, dev);
 578                urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 579                usb_anchor_urb(urb, &dev->rx_submitted);
 580
 581                err = usb_submit_urb(urb, GFP_KERNEL);
 582                if (err) {
 583                        usb_unanchor_urb(urb);
 584                        usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
 585                                          urb->transfer_dma);
 586                }
 587
 588freeurb:
 589                /* Drop reference, USB core will take care of freeing it */
 590                usb_free_urb(urb);
 591                if (err)
 592                        break;
 593        }
 594
 595        /* Did we submit any URBs */
 596        if (i == 0) {
 597                dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
 598                return err;
 599        }
 600
 601        /* Warn if we've couldn't transmit all the URBs */
 602        if (i < MAX_RX_URBS) {
 603                dev_warn(dev->udev->dev.parent,
 604                         "rx performance may be slow\n");
 605        }
 606
 607        dev->rxinitdone = 1;
 608        return 0;
 609}
 610
 611/*
 612 * Start interface
 613 */
 614static int esd_usb2_start(struct esd_usb2_net_priv *priv)
 615{
 616        struct esd_usb2 *dev = priv->usb2;
 617        struct net_device *netdev = priv->netdev;
 618        struct esd_usb2_msg *msg;
 619        int err, i;
 620
 621        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 622        if (!msg) {
 623                err = -ENOMEM;
 624                goto out;
 625        }
 626
 627        /*
 628         * Enable all IDs
 629         * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
 630         * Each bit represents one 11 bit CAN identifier. A set bit
 631         * enables reception of the corresponding CAN identifier. A cleared
 632         * bit disabled this identifier. An additional bitmask value
 633         * following the CAN 2.0A bits is used to enable reception of
 634         * extended CAN frames. Only the LSB of this final mask is checked
 635         * for the complete 29 bit ID range. The IDADD message also allows
 636         * filter configuration for an ID subset. In this case you can add
 637         * the number of the starting bitmask (0..64) to the filter.option
 638         * field followed by only some bitmasks.
 639         */
 640        msg->msg.hdr.cmd = CMD_IDADD;
 641        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 642        msg->msg.filter.net = priv->index;
 643        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 644        for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
 645                msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
 646        /* enable 29bit extended IDs */
 647        msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
 648
 649        err = esd_usb2_send_msg(dev, msg);
 650        if (err)
 651                goto out;
 652
 653        err = esd_usb2_setup_rx_urbs(dev);
 654        if (err)
 655                goto out;
 656
 657        priv->can.state = CAN_STATE_ERROR_ACTIVE;
 658
 659out:
 660        if (err == -ENODEV)
 661                netif_device_detach(netdev);
 662        if (err)
 663                netdev_err(netdev, "couldn't start device: %d\n", err);
 664
 665        kfree(msg);
 666        return err;
 667}
 668
 669static void unlink_all_urbs(struct esd_usb2 *dev)
 670{
 671        struct esd_usb2_net_priv *priv;
 672        int i, j;
 673
 674        usb_kill_anchored_urbs(&dev->rx_submitted);
 675        for (i = 0; i < dev->net_count; i++) {
 676                priv = dev->nets[i];
 677                if (priv) {
 678                        usb_kill_anchored_urbs(&priv->tx_submitted);
 679                        atomic_set(&priv->active_tx_jobs, 0);
 680
 681                        for (j = 0; j < MAX_TX_URBS; j++)
 682                                priv->tx_contexts[j].echo_index = MAX_TX_URBS;
 683                }
 684        }
 685}
 686
 687static int esd_usb2_open(struct net_device *netdev)
 688{
 689        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 690        int err;
 691
 692        /* common open */
 693        err = open_candev(netdev);
 694        if (err)
 695                return err;
 696
 697        /* finally start device */
 698        err = esd_usb2_start(priv);
 699        if (err) {
 700                netdev_warn(netdev, "couldn't start device: %d\n", err);
 701                close_candev(netdev);
 702                return err;
 703        }
 704
 705        netif_start_queue(netdev);
 706
 707        return 0;
 708}
 709
 710static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
 711                                      struct net_device *netdev)
 712{
 713        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 714        struct esd_usb2 *dev = priv->usb2;
 715        struct esd_tx_urb_context *context = NULL;
 716        struct net_device_stats *stats = &netdev->stats;
 717        struct can_frame *cf = (struct can_frame *)skb->data;
 718        struct esd_usb2_msg *msg;
 719        struct urb *urb;
 720        u8 *buf;
 721        int i, err;
 722        int ret = NETDEV_TX_OK;
 723        size_t size = sizeof(struct esd_usb2_msg);
 724
 725        if (can_dropped_invalid_skb(netdev, skb))
 726                return NETDEV_TX_OK;
 727
 728        /* create a URB, and a buffer for it, and copy the data to the URB */
 729        urb = usb_alloc_urb(0, GFP_ATOMIC);
 730        if (!urb) {
 731                stats->tx_dropped++;
 732                dev_kfree_skb(skb);
 733                goto nourbmem;
 734        }
 735
 736        buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
 737                                 &urb->transfer_dma);
 738        if (!buf) {
 739                netdev_err(netdev, "No memory left for USB buffer\n");
 740                stats->tx_dropped++;
 741                dev_kfree_skb(skb);
 742                goto nobufmem;
 743        }
 744
 745        msg = (struct esd_usb2_msg *)buf;
 746
 747        msg->msg.hdr.len = 3; /* minimal length */
 748        msg->msg.hdr.cmd = CMD_CAN_TX;
 749        msg->msg.tx.net = priv->index;
 750        msg->msg.tx.dlc = cf->can_dlc;
 751        msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
 752
 753        if (cf->can_id & CAN_RTR_FLAG)
 754                msg->msg.tx.dlc |= ESD_RTR;
 755
 756        if (cf->can_id & CAN_EFF_FLAG)
 757                msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
 758
 759        for (i = 0; i < cf->can_dlc; i++)
 760                msg->msg.tx.data[i] = cf->data[i];
 761
 762        msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
 763
 764        for (i = 0; i < MAX_TX_URBS; i++) {
 765                if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
 766                        context = &priv->tx_contexts[i];
 767                        break;
 768                }
 769        }
 770
 771        /*
 772         * This may never happen.
 773         */
 774        if (!context) {
 775                netdev_warn(netdev, "couldn't find free context\n");
 776                ret = NETDEV_TX_BUSY;
 777                goto releasebuf;
 778        }
 779
 780        context->priv = priv;
 781        context->echo_index = i;
 782        context->dlc = cf->can_dlc;
 783
 784        /* hnd must not be 0 - MSB is stripped in txdone handling */
 785        msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
 786
 787        usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
 788                          msg->msg.hdr.len << 2,
 789                          esd_usb2_write_bulk_callback, context);
 790
 791        urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 792
 793        usb_anchor_urb(urb, &priv->tx_submitted);
 794
 795        can_put_echo_skb(skb, netdev, context->echo_index);
 796
 797        atomic_inc(&priv->active_tx_jobs);
 798
 799        /* Slow down tx path */
 800        if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
 801                netif_stop_queue(netdev);
 802
 803        err = usb_submit_urb(urb, GFP_ATOMIC);
 804        if (err) {
 805                can_free_echo_skb(netdev, context->echo_index);
 806
 807                atomic_dec(&priv->active_tx_jobs);
 808                usb_unanchor_urb(urb);
 809
 810                stats->tx_dropped++;
 811
 812                if (err == -ENODEV)
 813                        netif_device_detach(netdev);
 814                else
 815                        netdev_warn(netdev, "failed tx_urb %d\n", err);
 816
 817                goto releasebuf;
 818        }
 819
 820        netif_trans_update(netdev);
 821
 822        /*
 823         * Release our reference to this URB, the USB core will eventually free
 824         * it entirely.
 825         */
 826        usb_free_urb(urb);
 827
 828        return NETDEV_TX_OK;
 829
 830releasebuf:
 831        usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
 832
 833nobufmem:
 834        usb_free_urb(urb);
 835
 836nourbmem:
 837        return ret;
 838}
 839
 840static int esd_usb2_close(struct net_device *netdev)
 841{
 842        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 843        struct esd_usb2_msg *msg;
 844        int i;
 845
 846        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 847        if (!msg)
 848                return -ENOMEM;
 849
 850        /* Disable all IDs (see esd_usb2_start()) */
 851        msg->msg.hdr.cmd = CMD_IDADD;
 852        msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 853        msg->msg.filter.net = priv->index;
 854        msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 855        for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
 856                msg->msg.filter.mask[i] = 0;
 857        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 858                netdev_err(netdev, "sending idadd message failed\n");
 859
 860        /* set CAN controller to reset mode */
 861        msg->msg.hdr.len = 2;
 862        msg->msg.hdr.cmd = CMD_SETBAUD;
 863        msg->msg.setbaud.net = priv->index;
 864        msg->msg.setbaud.rsvd = 0;
 865        msg->msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
 866        if (esd_usb2_send_msg(priv->usb2, msg) < 0)
 867                netdev_err(netdev, "sending setbaud message failed\n");
 868
 869        priv->can.state = CAN_STATE_STOPPED;
 870
 871        netif_stop_queue(netdev);
 872
 873        close_candev(netdev);
 874
 875        kfree(msg);
 876
 877        return 0;
 878}
 879
 880static const struct net_device_ops esd_usb2_netdev_ops = {
 881        .ndo_open = esd_usb2_open,
 882        .ndo_stop = esd_usb2_close,
 883        .ndo_start_xmit = esd_usb2_start_xmit,
 884        .ndo_change_mtu = can_change_mtu,
 885};
 886
 887static const struct can_bittiming_const esd_usb2_bittiming_const = {
 888        .name = "esd_usb2",
 889        .tseg1_min = ESD_USB2_TSEG1_MIN,
 890        .tseg1_max = ESD_USB2_TSEG1_MAX,
 891        .tseg2_min = ESD_USB2_TSEG2_MIN,
 892        .tseg2_max = ESD_USB2_TSEG2_MAX,
 893        .sjw_max = ESD_USB2_SJW_MAX,
 894        .brp_min = ESD_USB2_BRP_MIN,
 895        .brp_max = ESD_USB2_BRP_MAX,
 896        .brp_inc = ESD_USB2_BRP_INC,
 897};
 898
 899static int esd_usb2_set_bittiming(struct net_device *netdev)
 900{
 901        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 902        struct can_bittiming *bt = &priv->can.bittiming;
 903        struct esd_usb2_msg *msg;
 904        int err;
 905        u32 canbtr;
 906        int sjw_shift;
 907
 908        canbtr = ESD_USB2_UBR;
 909        if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
 910                canbtr |= ESD_USB2_LOM;
 911
 912        canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
 913
 914        if (le16_to_cpu(priv->usb2->udev->descriptor.idProduct) ==
 915            USB_CANUSBM_PRODUCT_ID)
 916                sjw_shift = ESD_USBM_SJW_SHIFT;
 917        else
 918                sjw_shift = ESD_USB2_SJW_SHIFT;
 919
 920        canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
 921                << sjw_shift;
 922        canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
 923                   & (ESD_USB2_TSEG1_MAX - 1))
 924                << ESD_USB2_TSEG1_SHIFT;
 925        canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
 926                << ESD_USB2_TSEG2_SHIFT;
 927        if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 928                canbtr |= ESD_USB2_3_SAMPLES;
 929
 930        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
 931        if (!msg)
 932                return -ENOMEM;
 933
 934        msg->msg.hdr.len = 2;
 935        msg->msg.hdr.cmd = CMD_SETBAUD;
 936        msg->msg.setbaud.net = priv->index;
 937        msg->msg.setbaud.rsvd = 0;
 938        msg->msg.setbaud.baud = cpu_to_le32(canbtr);
 939
 940        netdev_info(netdev, "setting BTR=%#x\n", canbtr);
 941
 942        err = esd_usb2_send_msg(priv->usb2, msg);
 943
 944        kfree(msg);
 945        return err;
 946}
 947
 948static int esd_usb2_get_berr_counter(const struct net_device *netdev,
 949                                     struct can_berr_counter *bec)
 950{
 951        struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 952
 953        bec->txerr = priv->bec.txerr;
 954        bec->rxerr = priv->bec.rxerr;
 955
 956        return 0;
 957}
 958
 959static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
 960{
 961        switch (mode) {
 962        case CAN_MODE_START:
 963                netif_wake_queue(netdev);
 964                break;
 965
 966        default:
 967                return -EOPNOTSUPP;
 968        }
 969
 970        return 0;
 971}
 972
 973static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
 974{
 975        struct esd_usb2 *dev = usb_get_intfdata(intf);
 976        struct net_device *netdev;
 977        struct esd_usb2_net_priv *priv;
 978        int err = 0;
 979        int i;
 980
 981        netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
 982        if (!netdev) {
 983                dev_err(&intf->dev, "couldn't alloc candev\n");
 984                err = -ENOMEM;
 985                goto done;
 986        }
 987
 988        priv = netdev_priv(netdev);
 989
 990        init_usb_anchor(&priv->tx_submitted);
 991        atomic_set(&priv->active_tx_jobs, 0);
 992
 993        for (i = 0; i < MAX_TX_URBS; i++)
 994                priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 995
 996        priv->usb2 = dev;
 997        priv->netdev = netdev;
 998        priv->index = index;
 999
1000        priv->can.state = CAN_STATE_STOPPED;
1001        priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY;
1002
1003        if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
1004            USB_CANUSBM_PRODUCT_ID)
1005                priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
1006        else {
1007                priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
1008                priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1009        }
1010
1011        priv->can.bittiming_const = &esd_usb2_bittiming_const;
1012        priv->can.do_set_bittiming = esd_usb2_set_bittiming;
1013        priv->can.do_set_mode = esd_usb2_set_mode;
1014        priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
1015
1016        netdev->flags |= IFF_ECHO; /* we support local echo */
1017
1018        netdev->netdev_ops = &esd_usb2_netdev_ops;
1019
1020        SET_NETDEV_DEV(netdev, &intf->dev);
1021        netdev->dev_id = index;
1022
1023        err = register_candev(netdev);
1024        if (err) {
1025                dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
1026                free_candev(netdev);
1027                err = -ENOMEM;
1028                goto done;
1029        }
1030
1031        dev->nets[index] = priv;
1032        netdev_info(netdev, "device %s registered\n", netdev->name);
1033
1034done:
1035        return err;
1036}
1037
1038/*
1039 * probe function for new USB2 devices
1040 *
1041 * check version information and number of available
1042 * CAN interfaces
1043 */
1044static int esd_usb2_probe(struct usb_interface *intf,
1045                         const struct usb_device_id *id)
1046{
1047        struct esd_usb2 *dev;
1048        struct esd_usb2_msg *msg;
1049        int i, err;
1050
1051        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1052        if (!dev) {
1053                err = -ENOMEM;
1054                goto done;
1055        }
1056
1057        dev->udev = interface_to_usbdev(intf);
1058
1059        init_usb_anchor(&dev->rx_submitted);
1060
1061        usb_set_intfdata(intf, dev);
1062
1063        msg = kmalloc(sizeof(*msg), GFP_KERNEL);
1064        if (!msg) {
1065                err = -ENOMEM;
1066                goto free_msg;
1067        }
1068
1069        /* query number of CAN interfaces (nets) */
1070        msg->msg.hdr.cmd = CMD_VERSION;
1071        msg->msg.hdr.len = 2;
1072        msg->msg.version.rsvd = 0;
1073        msg->msg.version.flags = 0;
1074        msg->msg.version.drv_version = 0;
1075
1076        err = esd_usb2_send_msg(dev, msg);
1077        if (err < 0) {
1078                dev_err(&intf->dev, "sending version message failed\n");
1079                goto free_msg;
1080        }
1081
1082        err = esd_usb2_wait_msg(dev, msg);
1083        if (err < 0) {
1084                dev_err(&intf->dev, "no version message answer\n");
1085                goto free_msg;
1086        }
1087
1088        dev->net_count = (int)msg->msg.version_reply.nets;
1089        dev->version = le32_to_cpu(msg->msg.version_reply.version);
1090
1091        if (device_create_file(&intf->dev, &dev_attr_firmware))
1092                dev_err(&intf->dev,
1093                        "Couldn't create device file for firmware\n");
1094
1095        if (device_create_file(&intf->dev, &dev_attr_hardware))
1096                dev_err(&intf->dev,
1097                        "Couldn't create device file for hardware\n");
1098
1099        if (device_create_file(&intf->dev, &dev_attr_nets))
1100                dev_err(&intf->dev,
1101                        "Couldn't create device file for nets\n");
1102
1103        /* do per device probing */
1104        for (i = 0; i < dev->net_count; i++)
1105                esd_usb2_probe_one_net(intf, i);
1106
1107free_msg:
1108        kfree(msg);
1109        if (err)
1110                kfree(dev);
1111done:
1112        return err;
1113}
1114
1115/*
1116 * called by the usb core when the device is removed from the system
1117 */
1118static void esd_usb2_disconnect(struct usb_interface *intf)
1119{
1120        struct esd_usb2 *dev = usb_get_intfdata(intf);
1121        struct net_device *netdev;
1122        int i;
1123
1124        device_remove_file(&intf->dev, &dev_attr_firmware);
1125        device_remove_file(&intf->dev, &dev_attr_hardware);
1126        device_remove_file(&intf->dev, &dev_attr_nets);
1127
1128        usb_set_intfdata(intf, NULL);
1129
1130        if (dev) {
1131                for (i = 0; i < dev->net_count; i++) {
1132                        if (dev->nets[i]) {
1133                                netdev = dev->nets[i]->netdev;
1134                                unregister_netdev(netdev);
1135                                free_candev(netdev);
1136                        }
1137                }
1138                unlink_all_urbs(dev);
1139                kfree(dev);
1140        }
1141}
1142
1143/* usb specific object needed to register this driver with the usb subsystem */
1144static struct usb_driver esd_usb2_driver = {
1145        .name = "esd_usb2",
1146        .probe = esd_usb2_probe,
1147        .disconnect = esd_usb2_disconnect,
1148        .id_table = esd_usb2_table,
1149};
1150
1151module_usb_driver(esd_usb2_driver);
1152
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