drivers/net/can/usb/esd_usb2.c

   1 /*
   2  * CAN driver for esd CAN-USB/2
   3  *
   4  * Copyright (C) 2010 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
  30 MODULE_AUTHOR("Matthias Fuchs <matthias.fuchs@esd.eu>");
  31 MODULE_DESCRIPTION("CAN driver for esd CAN-USB/2 interfaces");
  32 MODULE_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
  38 #define ESD_USB2_CAN_CLOCK      60000000
  39 #define ESD_USB2_MAX_NETS       2
  40
  41 /* USB2 commands */
  42 #define CMD_VERSION             1 /* also used for VERSION_REPLY */
  43 #define CMD_CAN_RX              2 /* device to host only */
  44 #define CMD_CAN_TX              3 /* also used for TX_DONE */
  45 #define CMD_SETBAUD             4 /* also used for SETBAUD_REPLY */
  46 #define CMD_TS                  5 /* also used for TS_REPLY */
  47 #define CMD_IDADD               6 /* also used for IDADD_REPLY */
  48
  49 /* esd CAN message flags - dlc field */
  50 #define ESD_RTR                 0x10
  51
  52 /* esd CAN message flags - id field */
  53 #define ESD_EXTID               0x20000000
  54 #define ESD_EVENT               0x40000000
  55 #define ESD_IDMASK              0x1fffffff
  56
  57 /* esd CAN event ids used by this driver */
  58 #define ESD_EV_CAN_ERROR_EXT    2
  59
  60 /* baudrate message flags */
  61 #define ESD_USB2_UBR            0x80000000
  62 #define ESD_USB2_LOM            0x40000000
  63 #define ESD_USB2_NO_BAUDRATE    0x7fffffff
  64 #define ESD_USB2_TSEG1_MIN      1
  65 #define ESD_USB2_TSEG1_MAX      16
  66 #define ESD_USB2_TSEG1_SHIFT    16
  67 #define ESD_USB2_TSEG2_MIN      1
  68 #define ESD_USB2_TSEG2_MAX      8
  69 #define ESD_USB2_TSEG2_SHIFT    20
  70 #define ESD_USB2_SJW_MAX        4
  71 #define ESD_USB2_SJW_SHIFT      14
  72 #define ESD_USB2_BRP_MIN        1
  73 #define ESD_USB2_BRP_MAX        1024
  74 #define ESD_USB2_BRP_INC        1
  75 #define ESD_USB2_3_SAMPLES      0x00800000
  76
  77 /* esd IDADD message */
  78 #define ESD_ID_ENABLE           0x80
  79 #define ESD_MAX_ID_SEGMENT      64
  80
  81 /* SJA1000 ECC register (emulated by usb2 firmware) */
  82 #define SJA1000_ECC_SEG         0x1F
  83 #define SJA1000_ECC_DIR         0x20
  84 #define SJA1000_ECC_ERR         0x06
  85 #define SJA1000_ECC_BIT         0x00
  86 #define SJA1000_ECC_FORM        0x40
  87 #define SJA1000_ECC_STUFF       0x80
  88 #define SJA1000_ECC_MASK        0xc0
  89
  90 /* esd bus state event codes */
  91 #define ESD_BUSSTATE_MASK       0xc0
  92 #define ESD_BUSSTATE_WARN       0x40
  93 #define ESD_BUSSTATE_ERRPASSIVE 0x80
  94 #define ESD_BUSSTATE_BUSOFF     0xc0
  95
  96 #define RX_BUFFER_SIZE          1024
  97 #define MAX_RX_URBS             4
  98 #define MAX_TX_URBS             16 /* must be power of 2 */
  99
 100 struct header_msg {
 101         u8 len; /* len is always the total message length in 32bit words */
 102         u8 cmd;
 103         u8 rsvd[2];
 104 };
 105
 106 struct version_msg {
 107         u8 len;
 108         u8 cmd;
 109         u8 rsvd;
 110         u8 flags;
 111         __le32 drv_version;
 112 };
 113
 114 struct version_reply_msg {
 115         u8 len;
 116         u8 cmd;
 117         u8 nets;
 118         u8 features;
 119         __le32 version;
 120         u8 name[16];
 121         __le32 rsvd;
 122         __le32 ts;
 123 };
 124
 125 struct rx_msg {
 126         u8 len;
 127         u8 cmd;
 128         u8 net;
 129         u8 dlc;
 130         __le32 ts;
 131         __le32 id; /* upper 3 bits contain flags */
 132         u8 data[8];
 133 };
 134
 135 struct tx_msg {
 136         u8 len;
 137         u8 cmd;
 138         u8 net;
 139         u8 dlc;
 140         __le32 hnd;
 141         __le32 id; /* upper 3 bits contain flags */
 142         u8 data[8];
 143 };
 144
 145 struct tx_done_msg {
 146         u8 len;
 147         u8 cmd;
 148         u8 net;
 149         u8 status;
 150         __le32 hnd;
 151         __le32 ts;
 152 };
 153
 154 struct id_filter_msg {
 155         u8 len;
 156         u8 cmd;
 157         u8 net;
 158         u8 option;
 159         __le32 mask[ESD_MAX_ID_SEGMENT + 1];
 160 };
 161
 162 struct set_baudrate_msg {
 163         u8 len;
 164         u8 cmd;
 165         u8 net;
 166         u8 rsvd;
 167         __le32 baud;
 168 };
 169
 170 /* Main message type used between library and application */
 171 struct __attribute__ ((packed)) esd_usb2_msg {
 172         union {
 173                 struct header_msg hdr;
 174                 struct version_msg version;
 175                 struct version_reply_msg version_reply;
 176                 struct rx_msg rx;
 177                 struct tx_msg tx;
 178                 struct tx_done_msg txdone;
 179                 struct set_baudrate_msg setbaud;
 180                 struct id_filter_msg filter;
 181         } msg;
 182 };
 183
 184 static struct usb_device_id esd_usb2_table[] = {
 185         {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
 186         {}
 187 };
 188 MODULE_DEVICE_TABLE(usb, esd_usb2_table);
 189
 190 struct esd_usb2_net_priv;
 191
 192 struct esd_tx_urb_context {
 193         struct esd_usb2_net_priv *priv;
 194         u32 echo_index;
 195         int dlc;
 196 };
 197
 198 struct esd_usb2 {
 199         struct usb_device *udev;
 200         struct esd_usb2_net_priv *nets[ESD_USB2_MAX_NETS];
 201
 202         struct usb_anchor rx_submitted;
 203
 204         int net_count;
 205         u32 version;
 206         int rxinitdone;
 207 };
 208
 209 struct esd_usb2_net_priv {
 210         struct can_priv can; /* must be the first member */
 211
 212         atomic_t active_tx_jobs;
 213         struct usb_anchor tx_submitted;
 214         struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
 215
 216         int open_time;
 217         struct esd_usb2 *usb2;
 218         struct net_device *netdev;
 219         int index;
 220         u8 old_state;
 221         struct can_berr_counter bec;
 222 };
 223
 224 static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
 225                               struct esd_usb2_msg *msg)
 226 {
 227         struct net_device_stats *stats = &priv->netdev->stats;
 228         struct can_frame *cf;
 229         struct sk_buff *skb;
 230         u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
 231
 232         if (id == ESD_EV_CAN_ERROR_EXT) {
 233                 u8 state = msg->msg.rx.data[0];
 234                 u8 ecc = msg->msg.rx.data[1];
 235                 u8 txerr = msg->msg.rx.data[2];
 236                 u8 rxerr = msg->msg.rx.data[3];
 237
 238                 skb = alloc_can_err_skb(priv->netdev, &cf);
 239                 if (skb == NULL) {
 240                         stats->rx_dropped++;
 241                         return;
 242                 }
 243
 244                 if (state != priv->old_state) {
 245                         priv->old_state = state;
 246
 247                         switch (state & ESD_BUSSTATE_MASK) {
 248                         case ESD_BUSSTATE_BUSOFF:
 249                                 priv->can.state = CAN_STATE_BUS_OFF;
 250                                 cf->can_id |= CAN_ERR_BUSOFF;
 251                                 can_bus_off(priv->netdev);
 252                                 break;
 253                         case ESD_BUSSTATE_WARN:
 254                                 priv->can.state = CAN_STATE_ERROR_WARNING;
 255                                 priv->can.can_stats.error_warning++;
 256                                 break;
 257                         case ESD_BUSSTATE_ERRPASSIVE:
 258                                 priv->can.state = CAN_STATE_ERROR_PASSIVE;
 259                                 priv->can.can_stats.error_passive++;
 260                                 break;
 261                         default:
 262                                 priv->can.state = CAN_STATE_ERROR_ACTIVE;
 263                                 break;
 264                         }
 265                 } else {
 266                         priv->can.can_stats.bus_error++;
 267                         stats->rx_errors++;
 268
 269                         cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
 270
 271                         switch (ecc & SJA1000_ECC_MASK) {
 272                         case SJA1000_ECC_BIT:
 273                                 cf->data[2] |= CAN_ERR_PROT_BIT;
 274                                 break;
 275                         case SJA1000_ECC_FORM:
 276                                 cf->data[2] |= CAN_ERR_PROT_FORM;
 277                                 break;
 278                         case SJA1000_ECC_STUFF:
 279                                 cf->data[2] |= CAN_ERR_PROT_STUFF;
 280                                 break;
 281                         default:
 282                                 cf->data[2] |= CAN_ERR_PROT_UNSPEC;
 283                                 cf->data[3] = ecc & SJA1000_ECC_SEG;
 284                                 break;
 285                         }
 286
 287                         /* Error occured during transmission? */
 288                         if (!(ecc & SJA1000_ECC_DIR))
 289                                 cf->data[2] |= CAN_ERR_PROT_TX;
 290
 291                         if (priv->can.state == CAN_STATE_ERROR_WARNING ||
 292                             priv->can.state == CAN_STATE_ERROR_PASSIVE) {
 293                                 cf->data[1] = (txerr > rxerr) ?
 294                                         CAN_ERR_CRTL_TX_PASSIVE :
 295                                         CAN_ERR_CRTL_RX_PASSIVE;
 296                         }
 297                         cf->data[6] = txerr;
 298                         cf->data[7] = rxerr;
 299                 }
 300
 301                 netif_rx(skb);
 302
 303                 priv->bec.txerr = txerr;
 304                 priv->bec.rxerr = rxerr;
 305
 306                 stats->rx_packets++;
 307                 stats->rx_bytes += cf->can_dlc;
 308         }
 309 }
 310
 311 static void esd_usb2_rx_can_msg(struct esd_usb2_net_priv *priv,
 312                                 struct esd_usb2_msg *msg)
 313 {
 314         struct net_device_stats *stats = &priv->netdev->stats;
 315         struct can_frame *cf;
 316         struct sk_buff *skb;
 317         int i;
 318         u32 id;
 319
 320         if (!netif_device_present(priv->netdev))
 321                 return;
 322
 323         id = le32_to_cpu(msg->msg.rx.id);
 324
 325         if (id & ESD_EVENT) {
 326                 esd_usb2_rx_event(priv, msg);
 327         } else {
 328                 skb = alloc_can_skb(priv->netdev, &cf);
 329                 if (skb == NULL) {
 330                         stats->rx_dropped++;
 331                         return;
 332                 }
 333
 334                 cf->can_id = id & ESD_IDMASK;
 335                 cf->can_dlc = get_can_dlc(msg->msg.rx.dlc);
 336
 337                 if (id & ESD_EXTID)
 338                         cf->can_id |= CAN_EFF_FLAG;
 339
 340                 if (msg->msg.rx.dlc & ESD_RTR) {
 341                         cf->can_id |= CAN_RTR_FLAG;
 342                 } else {
 343                         for (i = 0; i < cf->can_dlc; i++)
 344                                 cf->data[i] = msg->msg.rx.data[i];
 345                 }
 346
 347                 netif_rx(skb);
 348
 349                 stats->rx_packets++;
 350                 stats->rx_bytes += cf->can_dlc;
 351         }
 352
 353         return;
 354 }
 355
 356 static 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
 384 static 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                         esd_usb2_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
 413                         break;
 414
 415                 case CMD_CAN_TX:
 416                         esd_usb2_tx_done_msg(dev->nets[msg->msg.txdone.net],
 417                                              msg);
 418                         break;
 419                 }
 420
 421                 pos += msg->msg.hdr.len << 2;
 422
 423                 if (pos > urb->actual_length) {
 424                         dev_err(dev->udev->dev.parent, "format error\n");
 425                         break;
 426                 }
 427         }
 428
 429 resubmit_urb:
 430         usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
 431                           urb->transfer_buffer, RX_BUFFER_SIZE,
 432                           esd_usb2_read_bulk_callback, dev);
 433
 434         retval = usb_submit_urb(urb, GFP_ATOMIC);
 435         if (retval == -ENODEV) {
 436                 for (i = 0; i < dev->net_count; i++) {
 437                         if (dev->nets[i])
 438                                 netif_device_detach(dev->nets[i]->netdev);
 439                 }
 440         } else if (retval) {
 441                 dev_err(dev->udev->dev.parent,
 442                         "failed resubmitting read bulk urb: %d\n", retval);
 443         }
 444
 445         return;
 446 }
 447
 448 /*
 449  * callback for bulk IN urb
 450  */
 451 static void esd_usb2_write_bulk_callback(struct urb *urb)
 452 {
 453         struct esd_tx_urb_context *context = urb->context;
 454         struct esd_usb2_net_priv *priv;
 455         struct esd_usb2 *dev;
 456         struct net_device *netdev;
 457         size_t size = sizeof(struct esd_usb2_msg);
 458
 459         WARN_ON(!context);
 460
 461         priv = context->priv;
 462         netdev = priv->netdev;
 463         dev = priv->usb2;
 464
 465         /* free up our allocated buffer */
 466         usb_free_coherent(urb->dev, size,
 467                           urb->transfer_buffer, urb->transfer_dma);
 468
 469         if (!netif_device_present(netdev))
 470                 return;
 471
 472         if (urb->status)
 473                 dev_info(netdev->dev.parent, "Tx URB aborted (%d)\n",
 474                          urb->status);
 475
 476         netdev->trans_start = jiffies;
 477 }
 478
 479 static ssize_t show_firmware(struct device *d,
 480                              struct device_attribute *attr, char *buf)
 481 {
 482         struct usb_interface *intf = to_usb_interface(d);
 483         struct esd_usb2 *dev = usb_get_intfdata(intf);
 484
 485         return sprintf(buf, "%d.%d.%d\n",
 486                        (dev->version >> 12) & 0xf,
 487                        (dev->version >> 8) & 0xf,
 488                        dev->version & 0xff);
 489 }
 490 static DEVICE_ATTR(firmware, S_IRUGO, show_firmware, NULL);
 491
 492 static ssize_t show_hardware(struct device *d,
 493                              struct device_attribute *attr, char *buf)
 494 {
 495         struct usb_interface *intf = to_usb_interface(d);
 496         struct esd_usb2 *dev = usb_get_intfdata(intf);
 497
 498         return sprintf(buf, "%d.%d.%d\n",
 499                        (dev->version >> 28) & 0xf,
 500                        (dev->version >> 24) & 0xf,
 501                        (dev->version >> 16) & 0xff);
 502 }
 503 static DEVICE_ATTR(hardware, S_IRUGO, show_hardware, NULL);
 504
 505 static ssize_t show_nets(struct device *d,
 506                          struct device_attribute *attr, char *buf)
 507 {
 508         struct usb_interface *intf = to_usb_interface(d);
 509         struct esd_usb2 *dev = usb_get_intfdata(intf);
 510
 511         return sprintf(buf, "%d", dev->net_count);
 512 }
 513 static DEVICE_ATTR(nets, S_IRUGO, show_nets, NULL);
 514
 515 static int esd_usb2_send_msg(struct esd_usb2 *dev, struct esd_usb2_msg *msg)
 516 {
 517         int actual_length;
 518
 519         return usb_bulk_msg(dev->udev,
 520                             usb_sndbulkpipe(dev->udev, 2),
 521                             msg,
 522                             msg->msg.hdr.len << 2,
 523                             &actual_length,
 524                             1000);
 525 }
 526
 527 static int esd_usb2_wait_msg(struct esd_usb2 *dev,
 528                              struct esd_usb2_msg *msg)
 529 {
 530         int actual_length;
 531
 532         return usb_bulk_msg(dev->udev,
 533                             usb_rcvbulkpipe(dev->udev, 1),
 534                             msg,
 535                             sizeof(*msg),
 536                             &actual_length,
 537                             1000);
 538 }
 539
 540 static int esd_usb2_setup_rx_urbs(struct esd_usb2 *dev)
 541 {
 542         int i, err = 0;
 543
 544         if (dev->rxinitdone)
 545                 return 0;
 546
 547         for (i = 0; i < MAX_RX_URBS; i++) {
 548                 struct urb *urb = NULL;
 549                 u8 *buf = NULL;
 550
 551                 /* create a URB, and a buffer for it */
 552                 urb = usb_alloc_urb(0, GFP_KERNEL);
 553                 if (!urb) {
 554                         dev_warn(dev->udev->dev.parent,
 555                                  "No memory left for URBs\n");
 556                         err = -ENOMEM;
 557                         break;
 558                 }
 559
 560                 buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
 561                                          &urb->transfer_dma);
 562                 if (!buf) {
 563                         dev_warn(dev->udev->dev.parent,
 564                                  "No memory left for USB buffer\n");
 565                         err = -ENOMEM;
 566                         goto freeurb;
 567                 }
 568
 569                 usb_fill_bulk_urb(urb, dev->udev,
 570                                   usb_rcvbulkpipe(dev->udev, 1),
 571                                   buf, RX_BUFFER_SIZE,
 572                                   esd_usb2_read_bulk_callback, dev);
 573                 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 574                 usb_anchor_urb(urb, &dev->rx_submitted);
 575
 576                 err = usb_submit_urb(urb, GFP_KERNEL);
 577                 if (err) {
 578                         usb_unanchor_urb(urb);
 579                         usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
 580                                           urb->transfer_dma);
 581                 }
 582
 583 freeurb:
 584                 /* Drop reference, USB core will take care of freeing it */
 585                 usb_free_urb(urb);
 586                 if (err)
 587                         break;
 588         }
 589
 590         /* Did we submit any URBs */
 591         if (i == 0) {
 592                 dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
 593                 return err;
 594         }
 595
 596         /* Warn if we've couldn't transmit all the URBs */
 597         if (i < MAX_RX_URBS) {
 598                 dev_warn(dev->udev->dev.parent,
 599                          "rx performance may be slow\n");
 600         }
 601
 602         dev->rxinitdone = 1;
 603         return 0;
 604 }
 605
 606 /*
 607  * Start interface
 608  */
 609 static int esd_usb2_start(struct esd_usb2_net_priv *priv)
 610 {
 611         struct esd_usb2 *dev = priv->usb2;
 612         struct net_device *netdev = priv->netdev;
 613         struct esd_usb2_msg msg;
 614         int err, i;
 615
 616         /*
 617          * Enable all IDs
 618          * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
 619          * Each bit represents one 11 bit CAN identifier. A set bit
 620          * enables reception of the corresponding CAN identifier. A cleared
 621          * bit disabled this identifier. An additional bitmask value
 622          * following the CAN 2.0A bits is used to enable reception of
 623          * extended CAN frames. Only the LSB of this final mask is checked
 624          * for the complete 29 bit ID range. The IDADD message also allows
 625          * filter configuration for an ID subset. In this case you can add
 626          * the number of the starting bitmask (0..64) to the filter.option
 627          * field followed by only some bitmasks.
 628          */
 629         msg.msg.hdr.cmd = CMD_IDADD;
 630         msg.msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 631         msg.msg.filter.net = priv->index;
 632         msg.msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 633         for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
 634                 msg.msg.filter.mask[i] = cpu_to_le32(0xffffffff);
 635         /* enable 29bit extended IDs */
 636         msg.msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
 637
 638         err = esd_usb2_send_msg(dev, &msg);
 639         if (err)
 640                 goto failed;
 641
 642         err = esd_usb2_setup_rx_urbs(dev);
 643         if (err)
 644                 goto failed;
 645
 646         priv->can.state = CAN_STATE_ERROR_ACTIVE;
 647
 648         return 0;
 649
 650 failed:
 651         if (err == -ENODEV)
 652                 netif_device_detach(netdev);
 653
 654         dev_err(netdev->dev.parent, "couldn't start device: %d\n", err);
 655
 656         return err;
 657 }
 658
 659 static void unlink_all_urbs(struct esd_usb2 *dev)
 660 {
 661         struct esd_usb2_net_priv *priv;
 662         int i;
 663
 664         usb_kill_anchored_urbs(&dev->rx_submitted);
 665         for (i = 0; i < dev->net_count; i++) {
 666                 priv = dev->nets[i];
 667                 if (priv) {
 668                         usb_kill_anchored_urbs(&priv->tx_submitted);
 669                         atomic_set(&priv->active_tx_jobs, 0);
 670
 671                         for (i = 0; i < MAX_TX_URBS; i++)
 672                                 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 673                 }
 674         }
 675 }
 676
 677 static int esd_usb2_open(struct net_device *netdev)
 678 {
 679         struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 680         int err;
 681
 682         /* common open */
 683         err = open_candev(netdev);
 684         if (err)
 685                 return err;
 686
 687         /* finally start device */
 688         err = esd_usb2_start(priv);
 689         if (err) {
 690                 dev_warn(netdev->dev.parent,
 691                          "couldn't start device: %d\n", err);
 692                 close_candev(netdev);
 693                 return err;
 694         }
 695
 696         priv->open_time = jiffies;
 697
 698         netif_start_queue(netdev);
 699
 700         return 0;
 701 }
 702
 703 static netdev_tx_t esd_usb2_start_xmit(struct sk_buff *skb,
 704                                       struct net_device *netdev)
 705 {
 706         struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 707         struct esd_usb2 *dev = priv->usb2;
 708         struct esd_tx_urb_context *context = NULL;
 709         struct net_device_stats *stats = &netdev->stats;
 710         struct can_frame *cf = (struct can_frame *)skb->data;
 711         struct esd_usb2_msg *msg;
 712         struct urb *urb;
 713         u8 *buf;
 714         int i, err;
 715         int ret = NETDEV_TX_OK;
 716         size_t size = sizeof(struct esd_usb2_msg);
 717
 718         if (can_dropped_invalid_skb(netdev, skb))
 719                 return NETDEV_TX_OK;
 720
 721         /* create a URB, and a buffer for it, and copy the data to the URB */
 722         urb = usb_alloc_urb(0, GFP_ATOMIC);
 723         if (!urb) {
 724                 dev_err(netdev->dev.parent, "No memory left for URBs\n");
 725                 stats->tx_dropped++;
 726                 dev_kfree_skb(skb);
 727                 goto nourbmem;
 728         }
 729
 730         buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
 731                                  &urb->transfer_dma);
 732         if (!buf) {
 733                 dev_err(netdev->dev.parent, "No memory left for USB buffer\n");
 734                 stats->tx_dropped++;
 735                 dev_kfree_skb(skb);
 736                 goto nobufmem;
 737         }
 738
 739         msg = (struct esd_usb2_msg *)buf;
 740
 741         msg->msg.hdr.len = 3; /* minimal length */
 742         msg->msg.hdr.cmd = CMD_CAN_TX;
 743         msg->msg.tx.net = priv->index;
 744         msg->msg.tx.dlc = cf->can_dlc;
 745         msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
 746
 747         if (cf->can_id & CAN_RTR_FLAG)
 748                 msg->msg.tx.dlc |= ESD_RTR;
 749
 750         if (cf->can_id & CAN_EFF_FLAG)
 751                 msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
 752
 753         for (i = 0; i < cf->can_dlc; i++)
 754                 msg->msg.tx.data[i] = cf->data[i];
 755
 756         msg->msg.hdr.len += (cf->can_dlc + 3) >> 2;
 757
 758         for (i = 0; i < MAX_TX_URBS; i++) {
 759                 if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
 760                         context = &priv->tx_contexts[i];
 761                         break;
 762                 }
 763         }
 764
 765         /*
 766          * This may never happen.
 767          */
 768         if (!context) {
 769                 dev_warn(netdev->dev.parent, "couldn't find free context\n");
 770                 ret = NETDEV_TX_BUSY;
 771                 goto releasebuf;
 772         }
 773
 774         context->priv = priv;
 775         context->echo_index = i;
 776         context->dlc = cf->can_dlc;
 777
 778         /* hnd must not be 0 - MSB is stripped in txdone handling */
 779         msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
 780
 781         usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
 782                           msg->msg.hdr.len << 2,
 783                           esd_usb2_write_bulk_callback, context);
 784
 785         urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 786
 787         usb_anchor_urb(urb, &priv->tx_submitted);
 788
 789         can_put_echo_skb(skb, netdev, context->echo_index);
 790
 791         atomic_inc(&priv->active_tx_jobs);
 792
 793         /* Slow down tx path */
 794         if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
 795                 netif_stop_queue(netdev);
 796
 797         err = usb_submit_urb(urb, GFP_ATOMIC);
 798         if (err) {
 799                 can_free_echo_skb(netdev, context->echo_index);
 800
 801                 atomic_dec(&priv->active_tx_jobs);
 802                 usb_unanchor_urb(urb);
 803
 804                 stats->tx_dropped++;
 805
 806                 if (err == -ENODEV)
 807                         netif_device_detach(netdev);
 808                 else
 809                         dev_warn(netdev->dev.parent, "failed tx_urb %d\n", err);
 810
 811                 goto releasebuf;
 812         }
 813
 814         netdev->trans_start = jiffies;
 815
 816         /*
 817          * Release our reference to this URB, the USB core will eventually free
 818          * it entirely.
 819          */
 820         usb_free_urb(urb);
 821
 822         return NETDEV_TX_OK;
 823
 824 releasebuf:
 825         usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
 826
 827 nobufmem:
 828         usb_free_urb(urb);
 829
 830 nourbmem:
 831         return ret;
 832 }
 833
 834 static int esd_usb2_close(struct net_device *netdev)
 835 {
 836         struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 837         struct esd_usb2_msg msg;
 838         int i;
 839
 840         /* Disable all IDs (see esd_usb2_start()) */
 841         msg.msg.hdr.cmd = CMD_IDADD;
 842         msg.msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
 843         msg.msg.filter.net = priv->index;
 844         msg.msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
 845         for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
 846                 msg.msg.filter.mask[i] = 0;
 847         if (esd_usb2_send_msg(priv->usb2, &msg) < 0)
 848                 dev_err(netdev->dev.parent, "sending idadd message failed\n");
 849
 850         /* set CAN controller to reset mode */
 851         msg.msg.hdr.len = 2;
 852         msg.msg.hdr.cmd = CMD_SETBAUD;
 853         msg.msg.setbaud.net = priv->index;
 854         msg.msg.setbaud.rsvd = 0;
 855         msg.msg.setbaud.baud = cpu_to_le32(ESD_USB2_NO_BAUDRATE);
 856         if (esd_usb2_send_msg(priv->usb2, &msg) < 0)
 857                 dev_err(netdev->dev.parent, "sending setbaud message failed\n");
 858
 859         priv->can.state = CAN_STATE_STOPPED;
 860
 861         netif_stop_queue(netdev);
 862
 863         close_candev(netdev);
 864
 865         priv->open_time = 0;
 866
 867         return 0;
 868 }
 869
 870 static const struct net_device_ops esd_usb2_netdev_ops = {
 871         .ndo_open = esd_usb2_open,
 872         .ndo_stop = esd_usb2_close,
 873         .ndo_start_xmit = esd_usb2_start_xmit,
 874 };
 875
 876 static struct can_bittiming_const esd_usb2_bittiming_const = {
 877         .name = "esd_usb2",
 878         .tseg1_min = ESD_USB2_TSEG1_MIN,
 879         .tseg1_max = ESD_USB2_TSEG1_MAX,
 880         .tseg2_min = ESD_USB2_TSEG2_MIN,
 881         .tseg2_max = ESD_USB2_TSEG2_MAX,
 882         .sjw_max = ESD_USB2_SJW_MAX,
 883         .brp_min = ESD_USB2_BRP_MIN,
 884         .brp_max = ESD_USB2_BRP_MAX,
 885         .brp_inc = ESD_USB2_BRP_INC,
 886 };
 887
 888 static int esd_usb2_set_bittiming(struct net_device *netdev)
 889 {
 890         struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 891         struct can_bittiming *bt = &priv->can.bittiming;
 892         struct esd_usb2_msg msg;
 893         u32 canbtr;
 894
 895         canbtr = ESD_USB2_UBR;
 896         canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
 897         canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
 898                 << ESD_USB2_SJW_SHIFT;
 899         canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
 900                    & (ESD_USB2_TSEG1_MAX - 1))
 901                 << ESD_USB2_TSEG1_SHIFT;
 902         canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
 903                 << ESD_USB2_TSEG2_SHIFT;
 904         if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 905                 canbtr |= ESD_USB2_3_SAMPLES;
 906
 907         msg.msg.hdr.len = 2;
 908         msg.msg.hdr.cmd = CMD_SETBAUD;
 909         msg.msg.setbaud.net = priv->index;
 910         msg.msg.setbaud.rsvd = 0;
 911         msg.msg.setbaud.baud = cpu_to_le32(canbtr);
 912
 913         dev_info(netdev->dev.parent, "setting BTR=%#x\n", canbtr);
 914
 915         return esd_usb2_send_msg(priv->usb2, &msg);
 916 }
 917
 918 static int esd_usb2_get_berr_counter(const struct net_device *netdev,
 919                                      struct can_berr_counter *bec)
 920 {
 921         struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 922
 923         bec->txerr = priv->bec.txerr;
 924         bec->rxerr = priv->bec.rxerr;
 925
 926         return 0;
 927 }
 928
 929 static int esd_usb2_set_mode(struct net_device *netdev, enum can_mode mode)
 930 {
 931         struct esd_usb2_net_priv *priv = netdev_priv(netdev);
 932
 933         if (!priv->open_time)
 934                 return -EINVAL;
 935
 936         switch (mode) {
 937         case CAN_MODE_START:
 938                 netif_wake_queue(netdev);
 939                 break;
 940
 941         default:
 942                 return -EOPNOTSUPP;
 943         }
 944
 945         return 0;
 946 }
 947
 948 static int esd_usb2_probe_one_net(struct usb_interface *intf, int index)
 949 {
 950         struct esd_usb2 *dev = usb_get_intfdata(intf);
 951         struct net_device *netdev;
 952         struct esd_usb2_net_priv *priv;
 953         int err = 0;
 954         int i;
 955
 956         netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
 957         if (!netdev) {
 958                 dev_err(&intf->dev, "couldn't alloc candev\n");
 959                 err = -ENOMEM;
 960                 goto done;
 961         }
 962
 963         priv = netdev_priv(netdev);
 964
 965         init_usb_anchor(&priv->tx_submitted);
 966         atomic_set(&priv->active_tx_jobs, 0);
 967
 968         for (i = 0; i < MAX_TX_URBS; i++)
 969                 priv->tx_contexts[i].echo_index = MAX_TX_URBS;
 970
 971         priv->usb2 = dev;
 972         priv->netdev = netdev;
 973         priv->index = index;
 974
 975         priv->can.state = CAN_STATE_STOPPED;
 976         priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
 977         priv->can.bittiming_const = &esd_usb2_bittiming_const;
 978         priv->can.do_set_bittiming = esd_usb2_set_bittiming;
 979         priv->can.do_set_mode = esd_usb2_set_mode;
 980         priv->can.do_get_berr_counter = esd_usb2_get_berr_counter;
 981         priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
 982
 983         netdev->flags |= IFF_ECHO; /* we support local echo */
 984
 985         netdev->netdev_ops = &esd_usb2_netdev_ops;
 986
 987         SET_NETDEV_DEV(netdev, &intf->dev);
 988
 989         err = register_candev(netdev);
 990         if (err) {
 991                 dev_err(&intf->dev,
 992                         "couldn't register CAN device: %d\n", err);
 993                 free_candev(netdev);
 994                 err = -ENOMEM;
 995                 goto done;
 996         }
 997
 998         dev->nets[index] = priv;
 999         dev_info(netdev->dev.parent, "device %s registered\n", netdev->name);
1000
1001 done:
1002         return err;
1003 }
1004
1005 /*
1006  * probe function for new USB2 devices
1007  *
1008  * check version information and number of available
1009  * CAN interfaces
1010  */
1011 static int esd_usb2_probe(struct usb_interface *intf,
1012                          const struct usb_device_id *id)
1013 {
1014         struct esd_usb2 *dev;
1015         struct esd_usb2_msg msg;
1016         int i, err;
1017
1018         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1019         if (!dev) {
1020                 err = -ENOMEM;
1021                 goto done;
1022         }
1023
1024         dev->udev = interface_to_usbdev(intf);
1025
1026         init_usb_anchor(&dev->rx_submitted);
1027
1028         usb_set_intfdata(intf, dev);
1029
1030         /* query number of CAN interfaces (nets) */
1031         msg.msg.hdr.cmd = CMD_VERSION;
1032         msg.msg.hdr.len = 2;
1033         msg.msg.version.rsvd = 0;
1034         msg.msg.version.flags = 0;
1035         msg.msg.version.drv_version = 0;
1036
1037         err = esd_usb2_send_msg(dev, &msg);
1038         if (err < 0) {
1039                 dev_err(&intf->dev, "sending version message failed\n");
1040                 goto free_dev;
1041         }
1042
1043         err = esd_usb2_wait_msg(dev, &msg);
1044         if (err < 0) {
1045                 dev_err(&intf->dev, "no version message answer\n");
1046                 goto free_dev;
1047         }
1048
1049         dev->net_count = (int)msg.msg.version_reply.nets;
1050         dev->version = le32_to_cpu(msg.msg.version_reply.version);
1051
1052         if (device_create_file(&intf->dev, &dev_attr_firmware))
1053                 dev_err(&intf->dev,
1054                         "Couldn't create device file for firmware\n");
1055
1056         if (device_create_file(&intf->dev, &dev_attr_hardware))
1057                 dev_err(&intf->dev,
1058                         "Couldn't create device file for hardware\n");
1059
1060         if (device_create_file(&intf->dev, &dev_attr_nets))
1061                 dev_err(&intf->dev,
1062                         "Couldn't create device file for nets\n");
1063
1064         /* do per device probing */
1065         for (i = 0; i < dev->net_count; i++)
1066                 esd_usb2_probe_one_net(intf, i);
1067
1068         return 0;
1069
1070 free_dev:
1071         kfree(dev);
1072 done:
1073         return err;
1074 }
1075
1076 /*
1077  * called by the usb core when the device is removed from the system
1078  */
1079 static void esd_usb2_disconnect(struct usb_interface *intf)
1080 {
1081         struct esd_usb2 *dev = usb_get_intfdata(intf);
1082         struct net_device *netdev;
1083         int i;
1084
1085         device_remove_file(&intf->dev, &dev_attr_firmware);
1086         device_remove_file(&intf->dev, &dev_attr_hardware);
1087         device_remove_file(&intf->dev, &dev_attr_nets);
1088
1089         usb_set_intfdata(intf, NULL);
1090
1091         if (dev) {
1092                 for (i = 0; i < dev->net_count; i++) {
1093                         if (dev->nets[i]) {
1094                                 netdev = dev->nets[i]->netdev;
1095                                 unregister_netdev(netdev);
1096                                 free_candev(netdev);
1097                         }
1098                 }
1099                 unlink_all_urbs(dev);
1100         }
1101 }
1102
1103 /* usb specific object needed to register this driver with the usb subsystem */
1104 static struct usb_driver esd_usb2_driver = {
1105         .name = "esd_usb2",
1106         .probe = esd_usb2_probe,
1107         .disconnect = esd_usb2_disconnect,
1108         .id_table = esd_usb2_table,
1109 };
1110
1111 static int __init esd_usb2_init(void)
1112 {
1113         int err;
1114
1115         /* register this driver with the USB subsystem */
1116         err = usb_register(&esd_usb2_driver);
1117
1118         if (err) {
1119                 err("usb_register failed. Error number %d\n", err);
1120                 return err;
1121         }
1122
1123         return 0;
1124 }
1125 module_init(esd_usb2_init);
1126
1127 static void __exit esd_usb2_exit(void)
1128 {
1129         /* deregister this driver with the USB subsystem */
1130         usb_deregister(&esd_usb2_driver);
1131 }
1132 module_exit(esd_usb2_exit);