drivers/net/can/usb/peak_usb/pcan_usb_core.c

   1 /*
   2  * CAN driver for PEAK System USB adapters
   3  * Derived from the PCAN project file driver/src/pcan_usb_core.c
   4  *
   5  * Copyright (C) 2003-2010 PEAK System-Technik GmbH
   6  * Copyright (C) 2010-2012 Stephane Grosjean <s.grosjean@peak-system.com>
   7  *
   8  * Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de>
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published
  12  * by the Free Software Foundation; version 2 of the License.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  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 #include "pcan_usb_core.h"
  31
  32 MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
  33 MODULE_DESCRIPTION("CAN driver for PEAK-System USB adapters");
  34 MODULE_LICENSE("GPL v2");
  35
  36 /* Table of devices that work with this driver */
  37 static struct usb_device_id peak_usb_table[] = {
  38         {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USB_PRODUCT_ID)},
  39         {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPRO_PRODUCT_ID)},
  40         {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBFD_PRODUCT_ID)},
  41         {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPROFD_PRODUCT_ID)},
  42         {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBX6_PRODUCT_ID)},
  43         {} /* Terminating entry */
  44 };
  45
  46 MODULE_DEVICE_TABLE(usb, peak_usb_table);
  47
  48 /* List of supported PCAN-USB adapters (NULL terminated list) */
  49 static const struct peak_usb_adapter *const peak_usb_adapters_list[] = {
  50         &pcan_usb,
  51         &pcan_usb_pro,
  52         &pcan_usb_fd,
  53         &pcan_usb_pro_fd,
  54         &pcan_usb_x6,
  55 };
  56
  57 /*
  58  * dump memory
  59  */
  60 #define DUMP_WIDTH      16
  61 void pcan_dump_mem(char *prompt, void *p, int l)
  62 {
  63         pr_info("%s dumping %s (%d bytes):\n",
  64                 PCAN_USB_DRIVER_NAME, prompt ? prompt : "memory", l);
  65         print_hex_dump(KERN_INFO, PCAN_USB_DRIVER_NAME " ", DUMP_PREFIX_NONE,
  66                        DUMP_WIDTH, 1, p, l, false);
  67 }
  68
  69 /*
  70  * initialize a time_ref object with usb adapter own settings
  71  */
  72 void peak_usb_init_time_ref(struct peak_time_ref *time_ref,
  73                             const struct peak_usb_adapter *adapter)
  74 {
  75         if (time_ref) {
  76                 memset(time_ref, 0, sizeof(struct peak_time_ref));
  77                 time_ref->adapter = adapter;
  78         }
  79 }
  80
  81 static void peak_usb_add_us(struct timeval *tv, u32 delta_us)
  82 {
  83         /* number of s. to add to final time */
  84         u32 delta_s = delta_us / 1000000;
  85
  86         delta_us -= delta_s * 1000000;
  87
  88         tv->tv_usec += delta_us;
  89         if (tv->tv_usec >= 1000000) {
  90                 tv->tv_usec -= 1000000;
  91                 delta_s++;
  92         }
  93         tv->tv_sec += delta_s;
  94 }
  95
  96 /*
  97  * sometimes, another now may be  more recent than current one...
  98  */
  99 void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
 100 {
 101         time_ref->ts_dev_2 = ts_now;
 102
 103         /* should wait at least two passes before computing */
 104         if (time_ref->tv_host.tv_sec > 0) {
 105                 u32 delta_ts = time_ref->ts_dev_2 - time_ref->ts_dev_1;
 106
 107                 if (time_ref->ts_dev_2 < time_ref->ts_dev_1)
 108                         delta_ts &= (1 << time_ref->adapter->ts_used_bits) - 1;
 109
 110                 time_ref->ts_total += delta_ts;
 111         }
 112 }
 113
 114 /*
 115  * register device timestamp as now
 116  */
 117 void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
 118 {
 119         if (time_ref->tv_host_0.tv_sec == 0) {
 120                 /* use monotonic clock to correctly compute further deltas */
 121                 time_ref->tv_host_0 = ktime_to_timeval(ktime_get());
 122                 time_ref->tv_host.tv_sec = 0;
 123         } else {
 124                 /*
 125                  * delta_us should not be >= 2^32 => delta_s should be < 4294
 126                  * handle 32-bits wrapping here: if count of s. reaches 4200,
 127                  * reset counters and change time base
 128                  */
 129                 if (time_ref->tv_host.tv_sec != 0) {
 130                         u32 delta_s = time_ref->tv_host.tv_sec
 131                                                 - time_ref->tv_host_0.tv_sec;
 132                         if (delta_s > 4200) {
 133                                 time_ref->tv_host_0 = time_ref->tv_host;
 134                                 time_ref->ts_total = 0;
 135                         }
 136                 }
 137
 138                 time_ref->tv_host = ktime_to_timeval(ktime_get());
 139                 time_ref->tick_count++;
 140         }
 141
 142         time_ref->ts_dev_1 = time_ref->ts_dev_2;
 143         peak_usb_update_ts_now(time_ref, ts_now);
 144 }
 145
 146 /*
 147  * compute timeval according to current ts and time_ref data
 148  */
 149 void peak_usb_get_ts_tv(struct peak_time_ref *time_ref, u32 ts,
 150                         struct timeval *tv)
 151 {
 152         /* protect from getting timeval before setting now */
 153         if (time_ref->tv_host.tv_sec > 0) {
 154                 u64 delta_us;
 155
 156                 delta_us = ts - time_ref->ts_dev_2;
 157                 if (ts < time_ref->ts_dev_2)
 158                         delta_us &= (1 << time_ref->adapter->ts_used_bits) - 1;
 159
 160                 delta_us += time_ref->ts_total;
 161
 162                 delta_us *= time_ref->adapter->us_per_ts_scale;
 163                 delta_us >>= time_ref->adapter->us_per_ts_shift;
 164
 165                 *tv = time_ref->tv_host_0;
 166                 peak_usb_add_us(tv, (u32)delta_us);
 167         } else {
 168                 *tv = ktime_to_timeval(ktime_get());
 169         }
 170 }
 171
 172 /*
 173  * post received skb after having set any hw timestamp
 174  */
 175 int peak_usb_netif_rx(struct sk_buff *skb,
 176                       struct peak_time_ref *time_ref, u32 ts_low, u32 ts_high)
 177 {
 178         struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
 179         struct timeval tv;
 180
 181         peak_usb_get_ts_tv(time_ref, ts_low, &tv);
 182         hwts->hwtstamp = timeval_to_ktime(tv);
 183
 184         return netif_rx(skb);
 185 }
 186
 187 /*
 188  * callback for bulk Rx urb
 189  */
 190 static void peak_usb_read_bulk_callback(struct urb *urb)
 191 {
 192         struct peak_usb_device *dev = urb->context;
 193         struct net_device *netdev;
 194         int err;
 195
 196         netdev = dev->netdev;
 197
 198         if (!netif_device_present(netdev))
 199                 return;
 200
 201         /* check reception status */
 202         switch (urb->status) {
 203         case 0:
 204                 /* success */
 205                 break;
 206
 207         case -EILSEQ:
 208         case -ENOENT:
 209         case -ECONNRESET:
 210         case -ESHUTDOWN:
 211                 return;
 212
 213         default:
 214                 if (net_ratelimit())
 215                         netdev_err(netdev,
 216                                    "Rx urb aborted (%d)\n", urb->status);
 217                 goto resubmit_urb;
 218         }
 219
 220         /* protect from any incoming empty msgs */
 221         if ((urb->actual_length > 0) && (dev->adapter->dev_decode_buf)) {
 222                 /* handle these kinds of msgs only if _start callback called */
 223                 if (dev->state & PCAN_USB_STATE_STARTED) {
 224                         err = dev->adapter->dev_decode_buf(dev, urb);
 225                         if (err)
 226                                 pcan_dump_mem("received usb message",
 227                                               urb->transfer_buffer,
 228                                               urb->transfer_buffer_length);
 229                 }
 230         }
 231
 232 resubmit_urb:
 233         usb_fill_bulk_urb(urb, dev->udev,
 234                 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
 235                 urb->transfer_buffer, dev->adapter->rx_buffer_size,
 236                 peak_usb_read_bulk_callback, dev);
 237
 238         usb_anchor_urb(urb, &dev->rx_submitted);
 239         err = usb_submit_urb(urb, GFP_ATOMIC);
 240         if (!err)
 241                 return;
 242
 243         usb_unanchor_urb(urb);
 244
 245         if (err == -ENODEV)
 246                 netif_device_detach(netdev);
 247         else
 248                 netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
 249                            err);
 250 }
 251
 252 /*
 253  * callback for bulk Tx urb
 254  */
 255 static void peak_usb_write_bulk_callback(struct urb *urb)
 256 {
 257         struct peak_tx_urb_context *context = urb->context;
 258         struct peak_usb_device *dev;
 259         struct net_device *netdev;
 260
 261         BUG_ON(!context);
 262
 263         dev = context->dev;
 264         netdev = dev->netdev;
 265
 266         atomic_dec(&dev->active_tx_urbs);
 267
 268         if (!netif_device_present(netdev))
 269                 return;
 270
 271         /* check tx status */
 272         switch (urb->status) {
 273         case 0:
 274                 /* transmission complete */
 275                 netdev->stats.tx_packets++;
 276                 netdev->stats.tx_bytes += context->data_len;
 277
 278                 /* prevent tx timeout */
 279                 netif_trans_update(netdev);
 280                 break;
 281
 282         default:
 283                 if (net_ratelimit())
 284                         netdev_err(netdev, "Tx urb aborted (%d)\n",
 285                                    urb->status);
 286         case -EPROTO:
 287         case -ENOENT:
 288         case -ECONNRESET:
 289         case -ESHUTDOWN:
 290
 291                 break;
 292         }
 293
 294         /* should always release echo skb and corresponding context */
 295         can_get_echo_skb(netdev, context->echo_index);
 296         context->echo_index = PCAN_USB_MAX_TX_URBS;
 297
 298         /* do wakeup tx queue in case of success only */
 299         if (!urb->status)
 300                 netif_wake_queue(netdev);
 301 }
 302
 303 /*
 304  * called by netdev to send one skb on the CAN interface.
 305  */
 306 static netdev_tx_t peak_usb_ndo_start_xmit(struct sk_buff *skb,
 307                                            struct net_device *netdev)
 308 {
 309         struct peak_usb_device *dev = netdev_priv(netdev);
 310         struct peak_tx_urb_context *context = NULL;
 311         struct net_device_stats *stats = &netdev->stats;
 312         struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
 313         struct urb *urb;
 314         u8 *obuf;
 315         int i, err;
 316         size_t size = dev->adapter->tx_buffer_size;
 317
 318         if (can_dropped_invalid_skb(netdev, skb))
 319                 return NETDEV_TX_OK;
 320
 321         for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
 322                 if (dev->tx_contexts[i].echo_index == PCAN_USB_MAX_TX_URBS) {
 323                         context = dev->tx_contexts + i;
 324                         break;
 325                 }
 326
 327         if (!context) {
 328                 /* should not occur except during restart */
 329                 return NETDEV_TX_BUSY;
 330         }
 331
 332         urb = context->urb;
 333         obuf = urb->transfer_buffer;
 334
 335         err = dev->adapter->dev_encode_msg(dev, skb, obuf, &size);
 336         if (err) {
 337                 if (net_ratelimit())
 338                         netdev_err(netdev, "packet dropped\n");
 339                 dev_kfree_skb(skb);
 340                 stats->tx_dropped++;
 341                 return NETDEV_TX_OK;
 342         }
 343
 344         context->echo_index = i;
 345
 346         /* Note: this works with CANFD frames too */
 347         context->data_len = cfd->len;
 348
 349         usb_anchor_urb(urb, &dev->tx_submitted);
 350
 351         can_put_echo_skb(skb, netdev, context->echo_index);
 352
 353         atomic_inc(&dev->active_tx_urbs);
 354
 355         err = usb_submit_urb(urb, GFP_ATOMIC);
 356         if (err) {
 357                 can_free_echo_skb(netdev, context->echo_index);
 358
 359                 usb_unanchor_urb(urb);
 360
 361                 /* this context is not used in fact */
 362                 context->echo_index = PCAN_USB_MAX_TX_URBS;
 363
 364                 atomic_dec(&dev->active_tx_urbs);
 365
 366                 switch (err) {
 367                 case -ENODEV:
 368                         netif_device_detach(netdev);
 369                         break;
 370                 default:
 371                         netdev_warn(netdev, "tx urb submitting failed err=%d\n",
 372                                     err);
 373                 case -ENOENT:
 374                         /* cable unplugged */
 375                         stats->tx_dropped++;
 376                 }
 377         } else {
 378                 netif_trans_update(netdev);
 379
 380                 /* slow down tx path */
 381                 if (atomic_read(&dev->active_tx_urbs) >= PCAN_USB_MAX_TX_URBS)
 382                         netif_stop_queue(netdev);
 383         }
 384
 385         return NETDEV_TX_OK;
 386 }
 387
 388 /*
 389  * start the CAN interface.
 390  * Rx and Tx urbs are allocated here. Rx urbs are submitted here.
 391  */
 392 static int peak_usb_start(struct peak_usb_device *dev)
 393 {
 394         struct net_device *netdev = dev->netdev;
 395         int err, i;
 396
 397         for (i = 0; i < PCAN_USB_MAX_RX_URBS; i++) {
 398                 struct urb *urb;
 399                 u8 *buf;
 400
 401                 /* create a URB, and a buffer for it, to receive usb messages */
 402                 urb = usb_alloc_urb(0, GFP_KERNEL);
 403                 if (!urb) {
 404                         err = -ENOMEM;
 405                         break;
 406                 }
 407
 408                 buf = kmalloc(dev->adapter->rx_buffer_size, GFP_KERNEL);
 409                 if (!buf) {
 410                         usb_free_urb(urb);
 411                         err = -ENOMEM;
 412                         break;
 413                 }
 414
 415                 usb_fill_bulk_urb(urb, dev->udev,
 416                         usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
 417                         buf, dev->adapter->rx_buffer_size,
 418                         peak_usb_read_bulk_callback, dev);
 419
 420                 /* ask last usb_free_urb() to also kfree() transfer_buffer */
 421                 urb->transfer_flags |= URB_FREE_BUFFER;
 422                 usb_anchor_urb(urb, &dev->rx_submitted);
 423
 424                 err = usb_submit_urb(urb, GFP_KERNEL);
 425                 if (err) {
 426                         if (err == -ENODEV)
 427                                 netif_device_detach(dev->netdev);
 428
 429                         usb_unanchor_urb(urb);
 430                         kfree(buf);
 431                         usb_free_urb(urb);
 432                         break;
 433                 }
 434
 435                 /* drop reference, USB core will take care of freeing it */
 436                 usb_free_urb(urb);
 437         }
 438
 439         /* did we submit any URBs? Warn if we was not able to submit all urbs */
 440         if (i < PCAN_USB_MAX_RX_URBS) {
 441                 if (i == 0) {
 442                         netdev_err(netdev, "couldn't setup any rx URB\n");
 443                         return err;
 444                 }
 445
 446                 netdev_warn(netdev, "rx performance may be slow\n");
 447         }
 448
 449         /* pre-alloc tx buffers and corresponding urbs */
 450         for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
 451                 struct peak_tx_urb_context *context;
 452                 struct urb *urb;
 453                 u8 *buf;
 454
 455                 /* create a URB and a buffer for it, to transmit usb messages */
 456                 urb = usb_alloc_urb(0, GFP_KERNEL);
 457                 if (!urb) {
 458                         err = -ENOMEM;
 459                         break;
 460                 }
 461
 462                 buf = kmalloc(dev->adapter->tx_buffer_size, GFP_KERNEL);
 463                 if (!buf) {
 464                         usb_free_urb(urb);
 465                         err = -ENOMEM;
 466                         break;
 467                 }
 468
 469                 context = dev->tx_contexts + i;
 470                 context->dev = dev;
 471                 context->urb = urb;
 472
 473                 usb_fill_bulk_urb(urb, dev->udev,
 474                         usb_sndbulkpipe(dev->udev, dev->ep_msg_out),
 475                         buf, dev->adapter->tx_buffer_size,
 476                         peak_usb_write_bulk_callback, context);
 477
 478                 /* ask last usb_free_urb() to also kfree() transfer_buffer */
 479                 urb->transfer_flags |= URB_FREE_BUFFER;
 480         }
 481
 482         /* warn if we were not able to allocate enough tx contexts */
 483         if (i < PCAN_USB_MAX_TX_URBS) {
 484                 if (i == 0) {
 485                         netdev_err(netdev, "couldn't setup any tx URB\n");
 486                         goto err_tx;
 487                 }
 488
 489                 netdev_warn(netdev, "tx performance may be slow\n");
 490         }
 491
 492         if (dev->adapter->dev_start) {
 493                 err = dev->adapter->dev_start(dev);
 494                 if (err)
 495                         goto err_adapter;
 496         }
 497
 498         dev->state |= PCAN_USB_STATE_STARTED;
 499
 500         /* can set bus on now */
 501         if (dev->adapter->dev_set_bus) {
 502                 err = dev->adapter->dev_set_bus(dev, 1);
 503                 if (err)
 504                         goto err_adapter;
 505         }
 506
 507         dev->can.state = CAN_STATE_ERROR_ACTIVE;
 508
 509         return 0;
 510
 511 err_adapter:
 512         if (err == -ENODEV)
 513                 netif_device_detach(dev->netdev);
 514
 515         netdev_warn(netdev, "couldn't submit control: %d\n", err);
 516
 517         for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
 518                 usb_free_urb(dev->tx_contexts[i].urb);
 519                 dev->tx_contexts[i].urb = NULL;
 520         }
 521 err_tx:
 522         usb_kill_anchored_urbs(&dev->rx_submitted);
 523
 524         return err;
 525 }
 526
 527 /*
 528  * called by netdev to open the corresponding CAN interface.
 529  */
 530 static int peak_usb_ndo_open(struct net_device *netdev)
 531 {
 532         struct peak_usb_device *dev = netdev_priv(netdev);
 533         int err;
 534
 535         /* common open */
 536         err = open_candev(netdev);
 537         if (err)
 538                 return err;
 539
 540         /* finally start device */
 541         err = peak_usb_start(dev);
 542         if (err) {
 543                 netdev_err(netdev, "couldn't start device: %d\n", err);
 544                 close_candev(netdev);
 545                 return err;
 546         }
 547
 548         netif_start_queue(netdev);
 549
 550         return 0;
 551 }
 552
 553 /*
 554  * unlink in-flight Rx and Tx urbs and free their memory.
 555  */
 556 static void peak_usb_unlink_all_urbs(struct peak_usb_device *dev)
 557 {
 558         int i;
 559
 560         /* free all Rx (submitted) urbs */
 561         usb_kill_anchored_urbs(&dev->rx_submitted);
 562
 563         /* free unsubmitted Tx urbs first */
 564         for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
 565                 struct urb *urb = dev->tx_contexts[i].urb;
 566
 567                 if (!urb ||
 568                     dev->tx_contexts[i].echo_index != PCAN_USB_MAX_TX_URBS) {
 569                         /*
 570                          * this urb is already released or always submitted,
 571                          * let usb core free by itself
 572                          */
 573                         continue;
 574                 }
 575
 576                 usb_free_urb(urb);
 577                 dev->tx_contexts[i].urb = NULL;
 578         }
 579
 580         /* then free all submitted Tx urbs */
 581         usb_kill_anchored_urbs(&dev->tx_submitted);
 582         atomic_set(&dev->active_tx_urbs, 0);
 583 }
 584
 585 /*
 586  * called by netdev to close the corresponding CAN interface.
 587  */
 588 static int peak_usb_ndo_stop(struct net_device *netdev)
 589 {
 590         struct peak_usb_device *dev = netdev_priv(netdev);
 591
 592         dev->state &= ~PCAN_USB_STATE_STARTED;
 593         netif_stop_queue(netdev);
 594
 595         /* unlink all pending urbs and free used memory */
 596         peak_usb_unlink_all_urbs(dev);
 597
 598         if (dev->adapter->dev_stop)
 599                 dev->adapter->dev_stop(dev);
 600
 601         close_candev(netdev);
 602
 603         dev->can.state = CAN_STATE_STOPPED;
 604
 605         /* can set bus off now */
 606         if (dev->adapter->dev_set_bus) {
 607                 int err = dev->adapter->dev_set_bus(dev, 0);
 608                 if (err)
 609                         return err;
 610         }
 611
 612         return 0;
 613 }
 614
 615 /*
 616  * handle end of waiting for the device to reset
 617  */
 618 void peak_usb_restart_complete(struct peak_usb_device *dev)
 619 {
 620         /* finally MUST update can state */
 621         dev->can.state = CAN_STATE_ERROR_ACTIVE;
 622
 623         /* netdev queue can be awaken now */
 624         netif_wake_queue(dev->netdev);
 625 }
 626
 627 void peak_usb_async_complete(struct urb *urb)
 628 {
 629         kfree(urb->transfer_buffer);
 630         usb_free_urb(urb);
 631 }
 632
 633 /*
 634  * device (auto-)restart mechanism runs in a timer context =>
 635  * MUST handle restart with asynchronous usb transfers
 636  */
 637 static int peak_usb_restart(struct peak_usb_device *dev)
 638 {
 639         struct urb *urb;
 640         int err;
 641         u8 *buf;
 642
 643         /*
 644          * if device doesn't define any asynchronous restart handler, simply
 645          * wake the netdev queue up
 646          */
 647         if (!dev->adapter->dev_restart_async) {
 648                 peak_usb_restart_complete(dev);
 649                 return 0;
 650         }
 651
 652         /* first allocate a urb to handle the asynchronous steps */
 653         urb = usb_alloc_urb(0, GFP_ATOMIC);
 654         if (!urb)
 655                 return -ENOMEM;
 656
 657         /* also allocate enough space for the commands to send */
 658         buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_ATOMIC);
 659         if (!buf) {
 660                 usb_free_urb(urb);
 661                 return -ENOMEM;
 662         }
 663
 664         /* call the device specific handler for the restart */
 665         err = dev->adapter->dev_restart_async(dev, urb, buf);
 666         if (!err)
 667                 return 0;
 668
 669         kfree(buf);
 670         usb_free_urb(urb);
 671
 672         return err;
 673 }
 674
 675 /*
 676  * candev callback used to change CAN mode.
 677  * Warning: this is called from a timer context!
 678  */
 679 static int peak_usb_set_mode(struct net_device *netdev, enum can_mode mode)
 680 {
 681         struct peak_usb_device *dev = netdev_priv(netdev);
 682         int err = 0;
 683
 684         switch (mode) {
 685         case CAN_MODE_START:
 686                 err = peak_usb_restart(dev);
 687                 if (err)
 688                         netdev_err(netdev, "couldn't start device (err %d)\n",
 689                                    err);
 690                 break;
 691
 692         default:
 693                 return -EOPNOTSUPP;
 694         }
 695
 696         return err;
 697 }
 698
 699 /*
 700  * candev callback used to set device nominal/arbitration bitrate.
 701  */
 702 static int peak_usb_set_bittiming(struct net_device *netdev)
 703 {
 704         struct peak_usb_device *dev = netdev_priv(netdev);
 705         const struct peak_usb_adapter *pa = dev->adapter;
 706
 707         if (pa->dev_set_bittiming) {
 708                 struct can_bittiming *bt = &dev->can.bittiming;
 709                 int err = pa->dev_set_bittiming(dev, bt);
 710
 711                 if (err)
 712                         netdev_info(netdev, "couldn't set bitrate (err %d)\n",
 713                                     err);
 714                 return err;
 715         }
 716
 717         return 0;
 718 }
 719
 720 /*
 721  * candev callback used to set device data bitrate.
 722  */
 723 static int peak_usb_set_data_bittiming(struct net_device *netdev)
 724 {
 725         struct peak_usb_device *dev = netdev_priv(netdev);
 726         const struct peak_usb_adapter *pa = dev->adapter;
 727
 728         if (pa->dev_set_data_bittiming) {
 729                 struct can_bittiming *bt = &dev->can.data_bittiming;
 730                 int err = pa->dev_set_data_bittiming(dev, bt);
 731
 732                 if (err)
 733                         netdev_info(netdev,
 734                                     "couldn't set data bitrate (err %d)\n",
 735                                     err);
 736
 737                 return err;
 738         }
 739
 740         return 0;
 741 }
 742
 743 static const struct net_device_ops peak_usb_netdev_ops = {
 744         .ndo_open = peak_usb_ndo_open,
 745         .ndo_stop = peak_usb_ndo_stop,
 746         .ndo_start_xmit = peak_usb_ndo_start_xmit,
 747         .ndo_change_mtu = can_change_mtu,
 748 };
 749
 750 /*
 751  * create one device which is attached to CAN controller #ctrl_idx of the
 752  * usb adapter.
 753  */
 754 static int peak_usb_create_dev(const struct peak_usb_adapter *peak_usb_adapter,
 755                                struct usb_interface *intf, int ctrl_idx)
 756 {
 757         struct usb_device *usb_dev = interface_to_usbdev(intf);
 758         int sizeof_candev = peak_usb_adapter->sizeof_dev_private;
 759         struct peak_usb_device *dev;
 760         struct net_device *netdev;
 761         int i, err;
 762         u16 tmp16;
 763
 764         if (sizeof_candev < sizeof(struct peak_usb_device))
 765                 sizeof_candev = sizeof(struct peak_usb_device);
 766
 767         netdev = alloc_candev(sizeof_candev, PCAN_USB_MAX_TX_URBS);
 768         if (!netdev) {
 769                 dev_err(&intf->dev, "%s: couldn't alloc candev\n",
 770                         PCAN_USB_DRIVER_NAME);
 771                 return -ENOMEM;
 772         }
 773
 774         dev = netdev_priv(netdev);
 775
 776         /* allocate a buffer large enough to send commands */
 777         dev->cmd_buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_KERNEL);
 778         if (!dev->cmd_buf) {
 779                 err = -ENOMEM;
 780                 goto lbl_free_candev;
 781         }
 782
 783         dev->udev = usb_dev;
 784         dev->netdev = netdev;
 785         dev->adapter = peak_usb_adapter;
 786         dev->ctrl_idx = ctrl_idx;
 787         dev->state = PCAN_USB_STATE_CONNECTED;
 788
 789         dev->ep_msg_in = peak_usb_adapter->ep_msg_in;
 790         dev->ep_msg_out = peak_usb_adapter->ep_msg_out[ctrl_idx];
 791
 792         dev->can.clock = peak_usb_adapter->clock;
 793         dev->can.bittiming_const = peak_usb_adapter->bittiming_const;
 794         dev->can.do_set_bittiming = peak_usb_set_bittiming;
 795         dev->can.data_bittiming_const = peak_usb_adapter->data_bittiming_const;
 796         dev->can.do_set_data_bittiming = peak_usb_set_data_bittiming;
 797         dev->can.do_set_mode = peak_usb_set_mode;
 798         dev->can.do_get_berr_counter = peak_usb_adapter->do_get_berr_counter;
 799         dev->can.ctrlmode_supported = peak_usb_adapter->ctrlmode_supported;
 800
 801         netdev->netdev_ops = &peak_usb_netdev_ops;
 802
 803         netdev->flags |= IFF_ECHO; /* we support local echo */
 804
 805         init_usb_anchor(&dev->rx_submitted);
 806
 807         init_usb_anchor(&dev->tx_submitted);
 808         atomic_set(&dev->active_tx_urbs, 0);
 809
 810         for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
 811                 dev->tx_contexts[i].echo_index = PCAN_USB_MAX_TX_URBS;
 812
 813         dev->prev_siblings = usb_get_intfdata(intf);
 814         usb_set_intfdata(intf, dev);
 815
 816         SET_NETDEV_DEV(netdev, &intf->dev);
 817         netdev->dev_id = ctrl_idx;
 818
 819         err = register_candev(netdev);
 820         if (err) {
 821                 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
 822                 goto lbl_restore_intf_data;
 823         }
 824
 825         if (dev->prev_siblings)
 826                 (dev->prev_siblings)->next_siblings = dev;
 827
 828         /* keep hw revision into the netdevice */
 829         tmp16 = le16_to_cpu(usb_dev->descriptor.bcdDevice);
 830         dev->device_rev = tmp16 >> 8;
 831
 832         if (dev->adapter->dev_init) {
 833                 err = dev->adapter->dev_init(dev);
 834                 if (err)
 835                         goto lbl_unregister_candev;
 836         }
 837
 838         /* set bus off */
 839         if (dev->adapter->dev_set_bus) {
 840                 err = dev->adapter->dev_set_bus(dev, 0);
 841                 if (err)
 842                         goto lbl_unregister_candev;
 843         }
 844
 845         /* get device number early */
 846         if (dev->adapter->dev_get_device_id)
 847                 dev->adapter->dev_get_device_id(dev, &dev->device_number);
 848
 849         netdev_info(netdev, "attached to %s channel %u (device %u)\n",
 850                         peak_usb_adapter->name, ctrl_idx, dev->device_number);
 851
 852         return 0;
 853
 854 lbl_unregister_candev:
 855         unregister_candev(netdev);
 856
 857 lbl_restore_intf_data:
 858         usb_set_intfdata(intf, dev->prev_siblings);
 859         kfree(dev->cmd_buf);
 860
 861 lbl_free_candev:
 862         free_candev(netdev);
 863
 864         return err;
 865 }
 866
 867 /*
 868  * called by the usb core when the device is unplugged from the system
 869  */
 870 static void peak_usb_disconnect(struct usb_interface *intf)
 871 {
 872         struct peak_usb_device *dev;
 873         struct peak_usb_device *dev_prev_siblings;
 874
 875         /* unregister as many netdev devices as siblings */
 876         for (dev = usb_get_intfdata(intf); dev; dev = dev_prev_siblings) {
 877                 struct net_device *netdev = dev->netdev;
 878                 char name[IFNAMSIZ];
 879
 880                 dev_prev_siblings = dev->prev_siblings;
 881                 dev->state &= ~PCAN_USB_STATE_CONNECTED;
 882                 strncpy(name, netdev->name, IFNAMSIZ);
 883
 884                 unregister_netdev(netdev);
 885
 886                 kfree(dev->cmd_buf);
 887                 dev->next_siblings = NULL;
 888                 if (dev->adapter->dev_free)
 889                         dev->adapter->dev_free(dev);
 890
 891                 free_candev(netdev);
 892                 dev_info(&intf->dev, "%s removed\n", name);
 893         }
 894
 895         usb_set_intfdata(intf, NULL);
 896 }
 897
 898 /*
 899  * probe function for new PEAK-System devices
 900  */
 901 static int peak_usb_probe(struct usb_interface *intf,
 902                           const struct usb_device_id *id)
 903 {
 904         struct usb_device *usb_dev = interface_to_usbdev(intf);
 905         const u16 usb_id_product = le16_to_cpu(usb_dev->descriptor.idProduct);
 906         const struct peak_usb_adapter *peak_usb_adapter = NULL;
 907         int i, err = -ENOMEM;
 908
 909         usb_dev = interface_to_usbdev(intf);
 910
 911         /* get corresponding PCAN-USB adapter */
 912         for (i = 0; i < ARRAY_SIZE(peak_usb_adapters_list); i++)
 913                 if (peak_usb_adapters_list[i]->device_id == usb_id_product) {
 914                         peak_usb_adapter = peak_usb_adapters_list[i];
 915                         break;
 916                 }
 917
 918         if (!peak_usb_adapter) {
 919                 /* should never come except device_id bad usage in this file */
 920                 pr_err("%s: didn't find device id. 0x%x in devices list\n",
 921                         PCAN_USB_DRIVER_NAME, usb_dev->descriptor.idProduct);
 922                 return -ENODEV;
 923         }
 924
 925         /* got corresponding adapter: check if it handles current interface */
 926         if (peak_usb_adapter->intf_probe) {
 927                 err = peak_usb_adapter->intf_probe(intf);
 928                 if (err)
 929                         return err;
 930         }
 931
 932         for (i = 0; i < peak_usb_adapter->ctrl_count; i++) {
 933                 err = peak_usb_create_dev(peak_usb_adapter, intf, i);
 934                 if (err) {
 935                         /* deregister already created devices */
 936                         peak_usb_disconnect(intf);
 937                         break;
 938                 }
 939         }
 940
 941         return err;
 942 }
 943
 944 /* usb specific object needed to register this driver with the usb subsystem */
 945 static struct usb_driver peak_usb_driver = {
 946         .name = PCAN_USB_DRIVER_NAME,
 947         .disconnect = peak_usb_disconnect,
 948         .probe = peak_usb_probe,
 949         .id_table = peak_usb_table,
 950 };
 951
 952 static int __init peak_usb_init(void)
 953 {
 954         int err;
 955
 956         /* register this driver with the USB subsystem */
 957         err = usb_register(&peak_usb_driver);
 958         if (err)
 959                 pr_err("%s: usb_register failed (err %d)\n",
 960                         PCAN_USB_DRIVER_NAME, err);
 961
 962         return err;
 963 }
 964
 965 static int peak_usb_do_device_exit(struct device *d, void *arg)
 966 {
 967         struct usb_interface *intf = to_usb_interface(d);
 968         struct peak_usb_device *dev;
 969
 970         /* stop as many netdev devices as siblings */
 971         for (dev = usb_get_intfdata(intf); dev; dev = dev->prev_siblings) {
 972                 struct net_device *netdev = dev->netdev;
 973
 974                 if (netif_device_present(netdev))
 975                         if (dev->adapter->dev_exit)
 976                                 dev->adapter->dev_exit(dev);
 977         }
 978
 979         return 0;
 980 }
 981
 982 static void __exit peak_usb_exit(void)
 983 {
 984         int err;
 985
 986         /* last chance do send any synchronous commands here */
 987         err = driver_for_each_device(&peak_usb_driver.drvwrap.driver, NULL,
 988                                      NULL, peak_usb_do_device_exit);
 989         if (err)
 990                 pr_err("%s: failed to stop all can devices (err %d)\n",
 991                         PCAN_USB_DRIVER_NAME, err);
 992
 993         /* deregister this driver with the USB subsystem */
 994         usb_deregister(&peak_usb_driver);
 995
 996         pr_info("%s: PCAN-USB interfaces driver unloaded\n",
 997                 PCAN_USB_DRIVER_NAME);
 998 }
 999
1000 module_init(peak_usb_init);
1001 module_exit(peak_usb_exit);