drivers/net/can/usb/gs_usb.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* CAN driver for Geschwister Schneider USB/CAN devices
   3  * and bytewerk.org candleLight USB CAN interfaces.
   4  *
   5  * Copyright (C) 2013-2016 Geschwister Schneider Technologie-,
   6  * Entwicklungs- und Vertriebs UG (Haftungsbeschränkt).
   7  * Copyright (C) 2016 Hubert Denkmair
   8  *
   9  * Many thanks to all socketcan devs!
  10  */
  11
  12 #include <linux/bitfield.h>
  13 #include <linux/clocksource.h>
  14 #include <linux/ethtool.h>
  15 #include <linux/init.h>
  16 #include <linux/module.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/signal.h>
  19 #include <linux/timecounter.h>
  20 #include <linux/units.h>
  21 #include <linux/usb.h>
  22 #include <linux/workqueue.h>
  23
  24 #include <linux/can.h>
  25 #include <linux/can/dev.h>
  26 #include <linux/can/error.h>
  27
  28 /* Device specific constants */
  29 #define USB_GS_USB_1_VENDOR_ID 0x1d50
  30 #define USB_GS_USB_1_PRODUCT_ID 0x606f
  31
  32 #define USB_CANDLELIGHT_VENDOR_ID 0x1209
  33 #define USB_CANDLELIGHT_PRODUCT_ID 0x2323
  34
  35 #define USB_CES_CANEXT_FD_VENDOR_ID 0x1cd2
  36 #define USB_CES_CANEXT_FD_PRODUCT_ID 0x606f
  37
  38 #define USB_ABE_CANDEBUGGER_FD_VENDOR_ID 0x16d0
  39 #define USB_ABE_CANDEBUGGER_FD_PRODUCT_ID 0x10b8
  40
  41 #define GS_USB_ENDPOINT_IN 1
  42 #define GS_USB_ENDPOINT_OUT 2
  43
  44 /* Timestamp 32 bit timer runs at 1 MHz (1 µs tick). Worker accounts
  45  * for timer overflow (will be after ~71 minutes)
  46  */
  47 #define GS_USB_TIMESTAMP_TIMER_HZ (1 * HZ_PER_MHZ)
  48 #define GS_USB_TIMESTAMP_WORK_DELAY_SEC 1800
  49 static_assert(GS_USB_TIMESTAMP_WORK_DELAY_SEC <
  50               CYCLECOUNTER_MASK(32) / GS_USB_TIMESTAMP_TIMER_HZ / 2);
  51
  52 /* Device specific constants */
  53 enum gs_usb_breq {
  54         GS_USB_BREQ_HOST_FORMAT = 0,
  55         GS_USB_BREQ_BITTIMING,
  56         GS_USB_BREQ_MODE,
  57         GS_USB_BREQ_BERR,
  58         GS_USB_BREQ_BT_CONST,
  59         GS_USB_BREQ_DEVICE_CONFIG,
  60         GS_USB_BREQ_TIMESTAMP,
  61         GS_USB_BREQ_IDENTIFY,
  62         GS_USB_BREQ_GET_USER_ID,
  63         GS_USB_BREQ_QUIRK_CANTACT_PRO_DATA_BITTIMING = GS_USB_BREQ_GET_USER_ID,
  64         GS_USB_BREQ_SET_USER_ID,
  65         GS_USB_BREQ_DATA_BITTIMING,
  66         GS_USB_BREQ_BT_CONST_EXT,
  67         GS_USB_BREQ_SET_TERMINATION,
  68         GS_USB_BREQ_GET_TERMINATION,
  69         GS_USB_BREQ_GET_STATE,
  70 };
  71
  72 enum gs_can_mode {
  73         /* reset a channel. turns it off */
  74         GS_CAN_MODE_RESET = 0,
  75         /* starts a channel */
  76         GS_CAN_MODE_START
  77 };
  78
  79 enum gs_can_state {
  80         GS_CAN_STATE_ERROR_ACTIVE = 0,
  81         GS_CAN_STATE_ERROR_WARNING,
  82         GS_CAN_STATE_ERROR_PASSIVE,
  83         GS_CAN_STATE_BUS_OFF,
  84         GS_CAN_STATE_STOPPED,
  85         GS_CAN_STATE_SLEEPING
  86 };
  87
  88 enum gs_can_identify_mode {
  89         GS_CAN_IDENTIFY_OFF = 0,
  90         GS_CAN_IDENTIFY_ON
  91 };
  92
  93 enum gs_can_termination_state {
  94         GS_CAN_TERMINATION_STATE_OFF = 0,
  95         GS_CAN_TERMINATION_STATE_ON
  96 };
  97
  98 #define GS_USB_TERMINATION_DISABLED CAN_TERMINATION_DISABLED
  99 #define GS_USB_TERMINATION_ENABLED 120
 100
 101 /* data types passed between host and device */
 102
 103 /* The firmware on the original USB2CAN by Geschwister Schneider
 104  * Technologie Entwicklungs- und Vertriebs UG exchanges all data
 105  * between the host and the device in host byte order. This is done
 106  * with the struct gs_host_config::byte_order member, which is sent
 107  * first to indicate the desired byte order.
 108  *
 109  * The widely used open source firmware candleLight doesn't support
 110  * this feature and exchanges the data in little endian byte order.
 111  */
 112 struct gs_host_config {
 113         __le32 byte_order;
 114 } __packed;
 115
 116 struct gs_device_config {
 117         u8 reserved1;
 118         u8 reserved2;
 119         u8 reserved3;
 120         u8 icount;
 121         __le32 sw_version;
 122         __le32 hw_version;
 123 } __packed;
 124
 125 #define GS_CAN_MODE_NORMAL 0
 126 #define GS_CAN_MODE_LISTEN_ONLY BIT(0)
 127 #define GS_CAN_MODE_LOOP_BACK BIT(1)
 128 #define GS_CAN_MODE_TRIPLE_SAMPLE BIT(2)
 129 #define GS_CAN_MODE_ONE_SHOT BIT(3)
 130 #define GS_CAN_MODE_HW_TIMESTAMP BIT(4)
 131 /* GS_CAN_FEATURE_IDENTIFY BIT(5) */
 132 /* GS_CAN_FEATURE_USER_ID BIT(6) */
 133 #define GS_CAN_MODE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
 134 #define GS_CAN_MODE_FD BIT(8)
 135 /* GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9) */
 136 /* GS_CAN_FEATURE_BT_CONST_EXT BIT(10) */
 137 /* GS_CAN_FEATURE_TERMINATION BIT(11) */
 138 #define GS_CAN_MODE_BERR_REPORTING BIT(12)
 139 /* GS_CAN_FEATURE_GET_STATE BIT(13) */
 140
 141 struct gs_device_mode {
 142         __le32 mode;
 143         __le32 flags;
 144 } __packed;
 145
 146 struct gs_device_state {
 147         __le32 state;
 148         __le32 rxerr;
 149         __le32 txerr;
 150 } __packed;
 151
 152 struct gs_device_bittiming {
 153         __le32 prop_seg;
 154         __le32 phase_seg1;
 155         __le32 phase_seg2;
 156         __le32 sjw;
 157         __le32 brp;
 158 } __packed;
 159
 160 struct gs_identify_mode {
 161         __le32 mode;
 162 } __packed;
 163
 164 struct gs_device_termination_state {
 165         __le32 state;
 166 } __packed;
 167
 168 #define GS_CAN_FEATURE_LISTEN_ONLY BIT(0)
 169 #define GS_CAN_FEATURE_LOOP_BACK BIT(1)
 170 #define GS_CAN_FEATURE_TRIPLE_SAMPLE BIT(2)
 171 #define GS_CAN_FEATURE_ONE_SHOT BIT(3)
 172 #define GS_CAN_FEATURE_HW_TIMESTAMP BIT(4)
 173 #define GS_CAN_FEATURE_IDENTIFY BIT(5)
 174 #define GS_CAN_FEATURE_USER_ID BIT(6)
 175 #define GS_CAN_FEATURE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
 176 #define GS_CAN_FEATURE_FD BIT(8)
 177 #define GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9)
 178 #define GS_CAN_FEATURE_BT_CONST_EXT BIT(10)
 179 #define GS_CAN_FEATURE_TERMINATION BIT(11)
 180 #define GS_CAN_FEATURE_BERR_REPORTING BIT(12)
 181 #define GS_CAN_FEATURE_GET_STATE BIT(13)
 182 #define GS_CAN_FEATURE_MASK GENMASK(13, 0)
 183
 184 /* internal quirks - keep in GS_CAN_FEATURE space for now */
 185
 186 /* CANtact Pro original firmware:
 187  * BREQ DATA_BITTIMING overlaps with GET_USER_ID
 188  */
 189 #define GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO BIT(31)
 190
 191 struct gs_device_bt_const {
 192         __le32 feature;
 193         __le32 fclk_can;
 194         __le32 tseg1_min;
 195         __le32 tseg1_max;
 196         __le32 tseg2_min;
 197         __le32 tseg2_max;
 198         __le32 sjw_max;
 199         __le32 brp_min;
 200         __le32 brp_max;
 201         __le32 brp_inc;
 202 } __packed;
 203
 204 struct gs_device_bt_const_extended {
 205         __le32 feature;
 206         __le32 fclk_can;
 207         __le32 tseg1_min;
 208         __le32 tseg1_max;
 209         __le32 tseg2_min;
 210         __le32 tseg2_max;
 211         __le32 sjw_max;
 212         __le32 brp_min;
 213         __le32 brp_max;
 214         __le32 brp_inc;
 215
 216         __le32 dtseg1_min;
 217         __le32 dtseg1_max;
 218         __le32 dtseg2_min;
 219         __le32 dtseg2_max;
 220         __le32 dsjw_max;
 221         __le32 dbrp_min;
 222         __le32 dbrp_max;
 223         __le32 dbrp_inc;
 224 } __packed;
 225
 226 #define GS_CAN_FLAG_OVERFLOW BIT(0)
 227 #define GS_CAN_FLAG_FD BIT(1)
 228 #define GS_CAN_FLAG_BRS BIT(2)
 229 #define GS_CAN_FLAG_ESI BIT(3)
 230
 231 struct classic_can {
 232         u8 data[8];
 233 } __packed;
 234
 235 struct classic_can_ts {
 236         u8 data[8];
 237         __le32 timestamp_us;
 238 } __packed;
 239
 240 struct classic_can_quirk {
 241         u8 data[8];
 242         u8 quirk;
 243 } __packed;
 244
 245 struct canfd {
 246         u8 data[64];
 247 } __packed;
 248
 249 struct canfd_ts {
 250         u8 data[64];
 251         __le32 timestamp_us;
 252 } __packed;
 253
 254 struct canfd_quirk {
 255         u8 data[64];
 256         u8 quirk;
 257 } __packed;
 258
 259 struct gs_host_frame {
 260         u32 echo_id;
 261         __le32 can_id;
 262
 263         u8 can_dlc;
 264         u8 channel;
 265         u8 flags;
 266         u8 reserved;
 267
 268         union {
 269                 DECLARE_FLEX_ARRAY(struct classic_can, classic_can);
 270                 DECLARE_FLEX_ARRAY(struct classic_can_ts, classic_can_ts);
 271                 DECLARE_FLEX_ARRAY(struct classic_can_quirk, classic_can_quirk);
 272                 DECLARE_FLEX_ARRAY(struct canfd, canfd);
 273                 DECLARE_FLEX_ARRAY(struct canfd_ts, canfd_ts);
 274                 DECLARE_FLEX_ARRAY(struct canfd_quirk, canfd_quirk);
 275         };
 276 } __packed;
 277 /* The GS USB devices make use of the same flags and masks as in
 278  * linux/can.h and linux/can/error.h, and no additional mapping is necessary.
 279  */
 280
 281 /* Only send a max of GS_MAX_TX_URBS frames per channel at a time. */
 282 #define GS_MAX_TX_URBS 10
 283 /* Only launch a max of GS_MAX_RX_URBS usb requests at a time. */
 284 #define GS_MAX_RX_URBS 30
 285 /* Maximum number of interfaces the driver supports per device.
 286  * Current hardware only supports 3 interfaces. The future may vary.
 287  */
 288 #define GS_MAX_INTF 3
 289
 290 struct gs_tx_context {
 291         struct gs_can *dev;
 292         unsigned int echo_id;
 293 };
 294
 295 struct gs_can {
 296         struct can_priv can; /* must be the first member */
 297
 298         struct gs_usb *parent;
 299
 300         struct net_device *netdev;
 301         struct usb_device *udev;
 302
 303         struct can_bittiming_const bt_const, data_bt_const;
 304         unsigned int channel;   /* channel number */
 305
 306         u32 feature;
 307         unsigned int hf_size_tx;
 308
 309         /* This lock prevents a race condition between xmit and receive. */
 310         spinlock_t tx_ctx_lock;
 311         struct gs_tx_context tx_context[GS_MAX_TX_URBS];
 312
 313         struct usb_anchor tx_submitted;
 314         atomic_t active_tx_urbs;
 315 };
 316
 317 /* usb interface struct */
 318 struct gs_usb {
 319         struct gs_can *canch[GS_MAX_INTF];
 320         struct usb_anchor rx_submitted;
 321         struct usb_device *udev;
 322
 323         /* time counter for hardware timestamps */
 324         struct cyclecounter cc;
 325         struct timecounter tc;
 326         spinlock_t tc_lock; /* spinlock to guard access tc->cycle_last */
 327         struct delayed_work timestamp;
 328
 329         unsigned int hf_size_rx;
 330         u8 active_channels;
 331 };
 332
 333 /* 'allocate' a tx context.
 334  * returns a valid tx context or NULL if there is no space.
 335  */
 336 static struct gs_tx_context *gs_alloc_tx_context(struct gs_can *dev)
 337 {
 338         int i = 0;
 339         unsigned long flags;
 340
 341         spin_lock_irqsave(&dev->tx_ctx_lock, flags);
 342
 343         for (; i < GS_MAX_TX_URBS; i++) {
 344                 if (dev->tx_context[i].echo_id == GS_MAX_TX_URBS) {
 345                         dev->tx_context[i].echo_id = i;
 346                         spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 347                         return &dev->tx_context[i];
 348                 }
 349         }
 350
 351         spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 352         return NULL;
 353 }
 354
 355 /* releases a tx context
 356  */
 357 static void gs_free_tx_context(struct gs_tx_context *txc)
 358 {
 359         txc->echo_id = GS_MAX_TX_URBS;
 360 }
 361
 362 /* Get a tx context by id.
 363  */
 364 static struct gs_tx_context *gs_get_tx_context(struct gs_can *dev,
 365                                                unsigned int id)
 366 {
 367         unsigned long flags;
 368
 369         if (id < GS_MAX_TX_URBS) {
 370                 spin_lock_irqsave(&dev->tx_ctx_lock, flags);
 371                 if (dev->tx_context[id].echo_id == id) {
 372                         spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 373                         return &dev->tx_context[id];
 374                 }
 375                 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 376         }
 377         return NULL;
 378 }
 379
 380 static int gs_cmd_reset(struct gs_can *dev)
 381 {
 382         struct gs_device_mode dm = {
 383                 .mode = GS_CAN_MODE_RESET,
 384         };
 385
 386         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_MODE,
 387                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 388                                     dev->channel, 0, &dm, sizeof(dm), 1000,
 389                                     GFP_KERNEL);
 390 }
 391
 392 static inline int gs_usb_get_timestamp(const struct gs_usb *parent,
 393                                        u32 *timestamp_p)
 394 {
 395         __le32 timestamp;
 396         int rc;
 397
 398         rc = usb_control_msg_recv(parent->udev, 0, GS_USB_BREQ_TIMESTAMP,
 399                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 400                                   0, 0,
 401                                   &timestamp, sizeof(timestamp),
 402                                   USB_CTRL_GET_TIMEOUT,
 403                                   GFP_KERNEL);
 404         if (rc)
 405                 return rc;
 406
 407         *timestamp_p = le32_to_cpu(timestamp);
 408
 409         return 0;
 410 }
 411
 412 static u64 gs_usb_timestamp_read(const struct cyclecounter *cc) __must_hold(&dev->tc_lock)
 413 {
 414         struct gs_usb *parent = container_of(cc, struct gs_usb, cc);
 415         u32 timestamp = 0;
 416         int err;
 417
 418         lockdep_assert_held(&parent->tc_lock);
 419
 420         /* drop lock for synchronous USB transfer */
 421         spin_unlock_bh(&parent->tc_lock);
 422         err = gs_usb_get_timestamp(parent, &timestamp);
 423         spin_lock_bh(&parent->tc_lock);
 424         if (err)
 425                 dev_err(&parent->udev->dev,
 426                         "Error %d while reading timestamp. HW timestamps may be inaccurate.",
 427                         err);
 428
 429         return timestamp;
 430 }
 431
 432 static void gs_usb_timestamp_work(struct work_struct *work)
 433 {
 434         struct delayed_work *delayed_work = to_delayed_work(work);
 435         struct gs_usb *parent;
 436
 437         parent = container_of(delayed_work, struct gs_usb, timestamp);
 438         spin_lock_bh(&parent->tc_lock);
 439         timecounter_read(&parent->tc);
 440         spin_unlock_bh(&parent->tc_lock);
 441
 442         schedule_delayed_work(&parent->timestamp,
 443                               GS_USB_TIMESTAMP_WORK_DELAY_SEC * HZ);
 444 }
 445
 446 static void gs_usb_skb_set_timestamp(struct gs_can *dev,
 447                                      struct sk_buff *skb, u32 timestamp)
 448 {
 449         struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
 450         struct gs_usb *parent = dev->parent;
 451         u64 ns;
 452
 453         spin_lock_bh(&parent->tc_lock);
 454         ns = timecounter_cyc2time(&parent->tc, timestamp);
 455         spin_unlock_bh(&parent->tc_lock);
 456
 457         hwtstamps->hwtstamp = ns_to_ktime(ns);
 458 }
 459
 460 static void gs_usb_timestamp_init(struct gs_usb *parent)
 461 {
 462         struct cyclecounter *cc = &parent->cc;
 463
 464         cc->read = gs_usb_timestamp_read;
 465         cc->mask = CYCLECOUNTER_MASK(32);
 466         cc->shift = 32 - bits_per(NSEC_PER_SEC / GS_USB_TIMESTAMP_TIMER_HZ);
 467         cc->mult = clocksource_hz2mult(GS_USB_TIMESTAMP_TIMER_HZ, cc->shift);
 468
 469         spin_lock_init(&parent->tc_lock);
 470         spin_lock_bh(&parent->tc_lock);
 471         timecounter_init(&parent->tc, &parent->cc, ktime_get_real_ns());
 472         spin_unlock_bh(&parent->tc_lock);
 473
 474         INIT_DELAYED_WORK(&parent->timestamp, gs_usb_timestamp_work);
 475         schedule_delayed_work(&parent->timestamp,
 476                               GS_USB_TIMESTAMP_WORK_DELAY_SEC * HZ);
 477 }
 478
 479 static void gs_usb_timestamp_stop(struct gs_usb *parent)
 480 {
 481         cancel_delayed_work_sync(&parent->timestamp);
 482 }
 483
 484 static void gs_update_state(struct gs_can *dev, struct can_frame *cf)
 485 {
 486         struct can_device_stats *can_stats = &dev->can.can_stats;
 487
 488         if (cf->can_id & CAN_ERR_RESTARTED) {
 489                 dev->can.state = CAN_STATE_ERROR_ACTIVE;
 490                 can_stats->restarts++;
 491         } else if (cf->can_id & CAN_ERR_BUSOFF) {
 492                 dev->can.state = CAN_STATE_BUS_OFF;
 493                 can_stats->bus_off++;
 494         } else if (cf->can_id & CAN_ERR_CRTL) {
 495                 if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) ||
 496                     (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) {
 497                         dev->can.state = CAN_STATE_ERROR_WARNING;
 498                         can_stats->error_warning++;
 499                 } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) ||
 500                            (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) {
 501                         dev->can.state = CAN_STATE_ERROR_PASSIVE;
 502                         can_stats->error_passive++;
 503                 } else {
 504                         dev->can.state = CAN_STATE_ERROR_ACTIVE;
 505                 }
 506         }
 507 }
 508
 509 static void gs_usb_set_timestamp(struct gs_can *dev, struct sk_buff *skb,
 510                                  const struct gs_host_frame *hf)
 511 {
 512         u32 timestamp;
 513
 514         if (!(dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP))
 515                 return;
 516
 517         if (hf->flags & GS_CAN_FLAG_FD)
 518                 timestamp = le32_to_cpu(hf->canfd_ts->timestamp_us);
 519         else
 520                 timestamp = le32_to_cpu(hf->classic_can_ts->timestamp_us);
 521
 522         gs_usb_skb_set_timestamp(dev, skb, timestamp);
 523 }
 524
 525 static void gs_usb_receive_bulk_callback(struct urb *urb)
 526 {
 527         struct gs_usb *usbcan = urb->context;
 528         struct gs_can *dev;
 529         struct net_device *netdev;
 530         int rc;
 531         struct net_device_stats *stats;
 532         struct gs_host_frame *hf = urb->transfer_buffer;
 533         struct gs_tx_context *txc;
 534         struct can_frame *cf;
 535         struct canfd_frame *cfd;
 536         struct sk_buff *skb;
 537
 538         BUG_ON(!usbcan);
 539
 540         switch (urb->status) {
 541         case 0: /* success */
 542                 break;
 543         case -ENOENT:
 544         case -ESHUTDOWN:
 545                 return;
 546         default:
 547                 /* do not resubmit aborted urbs. eg: when device goes down */
 548                 return;
 549         }
 550
 551         /* device reports out of range channel id */
 552         if (hf->channel >= GS_MAX_INTF)
 553                 goto device_detach;
 554
 555         dev = usbcan->canch[hf->channel];
 556
 557         netdev = dev->netdev;
 558         stats = &netdev->stats;
 559
 560         if (!netif_device_present(netdev))
 561                 return;
 562
 563         if (!netif_running(netdev))
 564                 goto resubmit_urb;
 565
 566         if (hf->echo_id == -1) { /* normal rx */
 567                 if (hf->flags & GS_CAN_FLAG_FD) {
 568                         skb = alloc_canfd_skb(dev->netdev, &cfd);
 569                         if (!skb)
 570                                 return;
 571
 572                         cfd->can_id = le32_to_cpu(hf->can_id);
 573                         cfd->len = can_fd_dlc2len(hf->can_dlc);
 574                         if (hf->flags & GS_CAN_FLAG_BRS)
 575                                 cfd->flags |= CANFD_BRS;
 576                         if (hf->flags & GS_CAN_FLAG_ESI)
 577                                 cfd->flags |= CANFD_ESI;
 578
 579                         memcpy(cfd->data, hf->canfd->data, cfd->len);
 580                 } else {
 581                         skb = alloc_can_skb(dev->netdev, &cf);
 582                         if (!skb)
 583                                 return;
 584
 585                         cf->can_id = le32_to_cpu(hf->can_id);
 586                         can_frame_set_cc_len(cf, hf->can_dlc, dev->can.ctrlmode);
 587
 588                         memcpy(cf->data, hf->classic_can->data, 8);
 589
 590                         /* ERROR frames tell us information about the controller */
 591                         if (le32_to_cpu(hf->can_id) & CAN_ERR_FLAG)
 592                                 gs_update_state(dev, cf);
 593                 }
 594
 595                 gs_usb_set_timestamp(dev, skb, hf);
 596
 597                 netdev->stats.rx_packets++;
 598                 netdev->stats.rx_bytes += hf->can_dlc;
 599
 600                 netif_rx(skb);
 601         } else { /* echo_id == hf->echo_id */
 602                 if (hf->echo_id >= GS_MAX_TX_URBS) {
 603                         netdev_err(netdev,
 604                                    "Unexpected out of range echo id %u\n",
 605                                    hf->echo_id);
 606                         goto resubmit_urb;
 607                 }
 608
 609                 txc = gs_get_tx_context(dev, hf->echo_id);
 610
 611                 /* bad devices send bad echo_ids. */
 612                 if (!txc) {
 613                         netdev_err(netdev,
 614                                    "Unexpected unused echo id %u\n",
 615                                    hf->echo_id);
 616                         goto resubmit_urb;
 617                 }
 618
 619                 skb = dev->can.echo_skb[hf->echo_id];
 620                 gs_usb_set_timestamp(dev, skb, hf);
 621
 622                 netdev->stats.tx_packets++;
 623                 netdev->stats.tx_bytes += can_get_echo_skb(netdev, hf->echo_id,
 624                                                            NULL);
 625
 626                 gs_free_tx_context(txc);
 627
 628                 atomic_dec(&dev->active_tx_urbs);
 629
 630                 netif_wake_queue(netdev);
 631         }
 632
 633         if (hf->flags & GS_CAN_FLAG_OVERFLOW) {
 634                 skb = alloc_can_err_skb(netdev, &cf);
 635                 if (!skb)
 636                         goto resubmit_urb;
 637
 638                 cf->can_id |= CAN_ERR_CRTL;
 639                 cf->len = CAN_ERR_DLC;
 640                 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 641                 stats->rx_over_errors++;
 642                 stats->rx_errors++;
 643                 netif_rx(skb);
 644         }
 645
 646 resubmit_urb:
 647         usb_fill_bulk_urb(urb, usbcan->udev,
 648                           usb_rcvbulkpipe(usbcan->udev, GS_USB_ENDPOINT_IN),
 649                           hf, dev->parent->hf_size_rx,
 650                           gs_usb_receive_bulk_callback, usbcan);
 651
 652         rc = usb_submit_urb(urb, GFP_ATOMIC);
 653
 654         /* USB failure take down all interfaces */
 655         if (rc == -ENODEV) {
 656 device_detach:
 657                 for (rc = 0; rc < GS_MAX_INTF; rc++) {
 658                         if (usbcan->canch[rc])
 659                                 netif_device_detach(usbcan->canch[rc]->netdev);
 660                 }
 661         }
 662 }
 663
 664 static int gs_usb_set_bittiming(struct net_device *netdev)
 665 {
 666         struct gs_can *dev = netdev_priv(netdev);
 667         struct can_bittiming *bt = &dev->can.bittiming;
 668         struct gs_device_bittiming dbt = {
 669                 .prop_seg = cpu_to_le32(bt->prop_seg),
 670                 .phase_seg1 = cpu_to_le32(bt->phase_seg1),
 671                 .phase_seg2 = cpu_to_le32(bt->phase_seg2),
 672                 .sjw = cpu_to_le32(bt->sjw),
 673                 .brp = cpu_to_le32(bt->brp),
 674         };
 675
 676         /* request bit timings */
 677         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_BITTIMING,
 678                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 679                                     dev->channel, 0, &dbt, sizeof(dbt), 1000,
 680                                     GFP_KERNEL);
 681 }
 682
 683 static int gs_usb_set_data_bittiming(struct net_device *netdev)
 684 {
 685         struct gs_can *dev = netdev_priv(netdev);
 686         struct can_bittiming *bt = &dev->can.data_bittiming;
 687         struct gs_device_bittiming dbt = {
 688                 .prop_seg = cpu_to_le32(bt->prop_seg),
 689                 .phase_seg1 = cpu_to_le32(bt->phase_seg1),
 690                 .phase_seg2 = cpu_to_le32(bt->phase_seg2),
 691                 .sjw = cpu_to_le32(bt->sjw),
 692                 .brp = cpu_to_le32(bt->brp),
 693         };
 694         u8 request = GS_USB_BREQ_DATA_BITTIMING;
 695
 696         if (dev->feature & GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO)
 697                 request = GS_USB_BREQ_QUIRK_CANTACT_PRO_DATA_BITTIMING;
 698
 699         /* request data bit timings */
 700         return usb_control_msg_send(dev->udev, 0, request,
 701                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 702                                     dev->channel, 0, &dbt, sizeof(dbt), 1000,
 703                                     GFP_KERNEL);
 704 }
 705
 706 static void gs_usb_xmit_callback(struct urb *urb)
 707 {
 708         struct gs_tx_context *txc = urb->context;
 709         struct gs_can *dev = txc->dev;
 710         struct net_device *netdev = dev->netdev;
 711
 712         if (urb->status)
 713                 netdev_info(netdev, "usb xmit fail %u\n", txc->echo_id);
 714 }
 715
 716 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb,
 717                                      struct net_device *netdev)
 718 {
 719         struct gs_can *dev = netdev_priv(netdev);
 720         struct net_device_stats *stats = &dev->netdev->stats;
 721         struct urb *urb;
 722         struct gs_host_frame *hf;
 723         struct can_frame *cf;
 724         struct canfd_frame *cfd;
 725         int rc;
 726         unsigned int idx;
 727         struct gs_tx_context *txc;
 728
 729         if (can_dev_dropped_skb(netdev, skb))
 730                 return NETDEV_TX_OK;
 731
 732         /* find an empty context to keep track of transmission */
 733         txc = gs_alloc_tx_context(dev);
 734         if (!txc)
 735                 return NETDEV_TX_BUSY;
 736
 737         /* create a URB, and a buffer for it */
 738         urb = usb_alloc_urb(0, GFP_ATOMIC);
 739         if (!urb)
 740                 goto nomem_urb;
 741
 742         hf = kmalloc(dev->hf_size_tx, GFP_ATOMIC);
 743         if (!hf) {
 744                 netdev_err(netdev, "No memory left for USB buffer\n");
 745                 goto nomem_hf;
 746         }
 747
 748         idx = txc->echo_id;
 749
 750         if (idx >= GS_MAX_TX_URBS) {
 751                 netdev_err(netdev, "Invalid tx context %u\n", idx);
 752                 goto badidx;
 753         }
 754
 755         hf->echo_id = idx;
 756         hf->channel = dev->channel;
 757         hf->flags = 0;
 758         hf->reserved = 0;
 759
 760         if (can_is_canfd_skb(skb)) {
 761                 cfd = (struct canfd_frame *)skb->data;
 762
 763                 hf->can_id = cpu_to_le32(cfd->can_id);
 764                 hf->can_dlc = can_fd_len2dlc(cfd->len);
 765                 hf->flags |= GS_CAN_FLAG_FD;
 766                 if (cfd->flags & CANFD_BRS)
 767                         hf->flags |= GS_CAN_FLAG_BRS;
 768                 if (cfd->flags & CANFD_ESI)
 769                         hf->flags |= GS_CAN_FLAG_ESI;
 770
 771                 memcpy(hf->canfd->data, cfd->data, cfd->len);
 772         } else {
 773                 cf = (struct can_frame *)skb->data;
 774
 775                 hf->can_id = cpu_to_le32(cf->can_id);
 776                 hf->can_dlc = can_get_cc_dlc(cf, dev->can.ctrlmode);
 777
 778                 memcpy(hf->classic_can->data, cf->data, cf->len);
 779         }
 780
 781         usb_fill_bulk_urb(urb, dev->udev,
 782                           usb_sndbulkpipe(dev->udev, GS_USB_ENDPOINT_OUT),
 783                           hf, dev->hf_size_tx,
 784                           gs_usb_xmit_callback, txc);
 785
 786         urb->transfer_flags |= URB_FREE_BUFFER;
 787         usb_anchor_urb(urb, &dev->tx_submitted);
 788
 789         can_put_echo_skb(skb, netdev, idx, 0);
 790
 791         atomic_inc(&dev->active_tx_urbs);
 792
 793         rc = usb_submit_urb(urb, GFP_ATOMIC);
 794         if (unlikely(rc)) {                     /* usb send failed */
 795                 atomic_dec(&dev->active_tx_urbs);
 796
 797                 can_free_echo_skb(netdev, idx, NULL);
 798                 gs_free_tx_context(txc);
 799
 800                 usb_unanchor_urb(urb);
 801
 802                 if (rc == -ENODEV) {
 803                         netif_device_detach(netdev);
 804                 } else {
 805                         netdev_err(netdev, "usb_submit failed (err=%d)\n", rc);
 806                         stats->tx_dropped++;
 807                 }
 808         } else {
 809                 /* Slow down tx path */
 810                 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS)
 811                         netif_stop_queue(netdev);
 812         }
 813
 814         /* let usb core take care of this urb */
 815         usb_free_urb(urb);
 816
 817         return NETDEV_TX_OK;
 818
 819 badidx:
 820         kfree(hf);
 821 nomem_hf:
 822         usb_free_urb(urb);
 823
 824 nomem_urb:
 825         gs_free_tx_context(txc);
 826         dev_kfree_skb(skb);
 827         stats->tx_dropped++;
 828         return NETDEV_TX_OK;
 829 }
 830
 831 static int gs_can_open(struct net_device *netdev)
 832 {
 833         struct gs_can *dev = netdev_priv(netdev);
 834         struct gs_usb *parent = dev->parent;
 835         struct gs_device_mode dm = {
 836                 .mode = cpu_to_le32(GS_CAN_MODE_START),
 837         };
 838         struct gs_host_frame *hf;
 839         struct urb *urb = NULL;
 840         u32 ctrlmode;
 841         u32 flags = 0;
 842         int rc, i;
 843
 844         rc = open_candev(netdev);
 845         if (rc)
 846                 return rc;
 847
 848         ctrlmode = dev->can.ctrlmode;
 849         if (ctrlmode & CAN_CTRLMODE_FD) {
 850                 if (dev->feature & GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX)
 851                         dev->hf_size_tx = struct_size(hf, canfd_quirk, 1);
 852                 else
 853                         dev->hf_size_tx = struct_size(hf, canfd, 1);
 854         } else {
 855                 if (dev->feature & GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX)
 856                         dev->hf_size_tx = struct_size(hf, classic_can_quirk, 1);
 857                 else
 858                         dev->hf_size_tx = struct_size(hf, classic_can, 1);
 859         }
 860
 861         if (!parent->active_channels) {
 862                 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
 863                         gs_usb_timestamp_init(parent);
 864
 865                 for (i = 0; i < GS_MAX_RX_URBS; i++) {
 866                         u8 *buf;
 867
 868                         /* alloc rx urb */
 869                         urb = usb_alloc_urb(0, GFP_KERNEL);
 870                         if (!urb) {
 871                                 rc = -ENOMEM;
 872                                 goto out_usb_kill_anchored_urbs;
 873                         }
 874
 875                         /* alloc rx buffer */
 876                         buf = kmalloc(dev->parent->hf_size_rx,
 877                                       GFP_KERNEL);
 878                         if (!buf) {
 879                                 netdev_err(netdev,
 880                                            "No memory left for USB buffer\n");
 881                                 rc = -ENOMEM;
 882                                 goto out_usb_free_urb;
 883                         }
 884
 885                         /* fill, anchor, and submit rx urb */
 886                         usb_fill_bulk_urb(urb,
 887                                           dev->udev,
 888                                           usb_rcvbulkpipe(dev->udev,
 889                                                           GS_USB_ENDPOINT_IN),
 890                                           buf,
 891                                           dev->parent->hf_size_rx,
 892                                           gs_usb_receive_bulk_callback, parent);
 893                         urb->transfer_flags |= URB_FREE_BUFFER;
 894
 895                         usb_anchor_urb(urb, &parent->rx_submitted);
 896
 897                         rc = usb_submit_urb(urb, GFP_KERNEL);
 898                         if (rc) {
 899                                 if (rc == -ENODEV)
 900                                         netif_device_detach(dev->netdev);
 901
 902                                 netdev_err(netdev,
 903                                            "usb_submit failed (err=%d)\n", rc);
 904
 905                                 goto out_usb_unanchor_urb;
 906                         }
 907
 908                         /* Drop reference,
 909                          * USB core will take care of freeing it
 910                          */
 911                         usb_free_urb(urb);
 912                 }
 913         }
 914
 915         /* flags */
 916         if (ctrlmode & CAN_CTRLMODE_LOOPBACK)
 917                 flags |= GS_CAN_MODE_LOOP_BACK;
 918
 919         if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
 920                 flags |= GS_CAN_MODE_LISTEN_ONLY;
 921
 922         if (ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 923                 flags |= GS_CAN_MODE_TRIPLE_SAMPLE;
 924
 925         if (ctrlmode & CAN_CTRLMODE_ONE_SHOT)
 926                 flags |= GS_CAN_MODE_ONE_SHOT;
 927
 928         if (ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
 929                 flags |= GS_CAN_MODE_BERR_REPORTING;
 930
 931         if (ctrlmode & CAN_CTRLMODE_FD)
 932                 flags |= GS_CAN_MODE_FD;
 933
 934         /* if hardware supports timestamps, enable it */
 935         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
 936                 flags |= GS_CAN_MODE_HW_TIMESTAMP;
 937
 938         /* finally start device */
 939         dev->can.state = CAN_STATE_ERROR_ACTIVE;
 940         dm.flags = cpu_to_le32(flags);
 941         rc = usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_MODE,
 942                                   USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 943                                   dev->channel, 0, &dm, sizeof(dm), 1000,
 944                                   GFP_KERNEL);
 945         if (rc) {
 946                 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc);
 947                 dev->can.state = CAN_STATE_STOPPED;
 948
 949                 goto out_usb_kill_anchored_urbs;
 950         }
 951
 952         parent->active_channels++;
 953         if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY))
 954                 netif_start_queue(netdev);
 955
 956         return 0;
 957
 958 out_usb_unanchor_urb:
 959         usb_unanchor_urb(urb);
 960 out_usb_free_urb:
 961         usb_free_urb(urb);
 962 out_usb_kill_anchored_urbs:
 963         if (!parent->active_channels) {
 964                 usb_kill_anchored_urbs(&dev->tx_submitted);
 965
 966                 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
 967                         gs_usb_timestamp_stop(parent);
 968         }
 969
 970         close_candev(netdev);
 971
 972         return rc;
 973 }
 974
 975 static int gs_usb_get_state(const struct net_device *netdev,
 976                             struct can_berr_counter *bec,
 977                             enum can_state *state)
 978 {
 979         struct gs_can *dev = netdev_priv(netdev);
 980         struct gs_device_state ds;
 981         int rc;
 982
 983         rc = usb_control_msg_recv(dev->udev, 0, GS_USB_BREQ_GET_STATE,
 984                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 985                                   dev->channel, 0,
 986                                   &ds, sizeof(ds),
 987                                   USB_CTRL_GET_TIMEOUT,
 988                                   GFP_KERNEL);
 989         if (rc)
 990                 return rc;
 991
 992         if (le32_to_cpu(ds.state) >= CAN_STATE_MAX)
 993                 return -EOPNOTSUPP;
 994
 995         *state = le32_to_cpu(ds.state);
 996         bec->txerr = le32_to_cpu(ds.txerr);
 997         bec->rxerr = le32_to_cpu(ds.rxerr);
 998
 999         return 0;
1000 }
1001
1002 static int gs_usb_can_get_berr_counter(const struct net_device *netdev,
1003                                        struct can_berr_counter *bec)
1004 {
1005         enum can_state state;
1006
1007         return gs_usb_get_state(netdev, bec, &state);
1008 }
1009
1010 static int gs_can_close(struct net_device *netdev)
1011 {
1012         int rc;
1013         struct gs_can *dev = netdev_priv(netdev);
1014         struct gs_usb *parent = dev->parent;
1015
1016         netif_stop_queue(netdev);
1017
1018         /* Stop polling */
1019         parent->active_channels--;
1020         if (!parent->active_channels) {
1021                 usb_kill_anchored_urbs(&parent->rx_submitted);
1022
1023                 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1024                         gs_usb_timestamp_stop(parent);
1025         }
1026
1027         /* Stop sending URBs */
1028         usb_kill_anchored_urbs(&dev->tx_submitted);
1029         atomic_set(&dev->active_tx_urbs, 0);
1030
1031         dev->can.state = CAN_STATE_STOPPED;
1032
1033         /* reset the device */
1034         rc = gs_cmd_reset(dev);
1035         if (rc < 0)
1036                 netdev_warn(netdev, "Couldn't shutdown device (err=%d)", rc);
1037
1038         /* reset tx contexts */
1039         for (rc = 0; rc < GS_MAX_TX_URBS; rc++) {
1040                 dev->tx_context[rc].dev = dev;
1041                 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS;
1042         }
1043
1044         /* close the netdev */
1045         close_candev(netdev);
1046
1047         return 0;
1048 }
1049
1050 static int gs_can_eth_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1051 {
1052         const struct gs_can *dev = netdev_priv(netdev);
1053
1054         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1055                 return can_eth_ioctl_hwts(netdev, ifr, cmd);
1056
1057         return -EOPNOTSUPP;
1058 }
1059
1060 static const struct net_device_ops gs_usb_netdev_ops = {
1061         .ndo_open = gs_can_open,
1062         .ndo_stop = gs_can_close,
1063         .ndo_start_xmit = gs_can_start_xmit,
1064         .ndo_change_mtu = can_change_mtu,
1065         .ndo_eth_ioctl = gs_can_eth_ioctl,
1066 };
1067
1068 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify)
1069 {
1070         struct gs_can *dev = netdev_priv(netdev);
1071         struct gs_identify_mode imode;
1072
1073         if (do_identify)
1074                 imode.mode = cpu_to_le32(GS_CAN_IDENTIFY_ON);
1075         else
1076                 imode.mode = cpu_to_le32(GS_CAN_IDENTIFY_OFF);
1077
1078         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_IDENTIFY,
1079                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1080                                     dev->channel, 0, &imode, sizeof(imode), 100,
1081                                     GFP_KERNEL);
1082 }
1083
1084 /* blink LED's for finding the this interface */
1085 static int gs_usb_set_phys_id(struct net_device *netdev,
1086                               enum ethtool_phys_id_state state)
1087 {
1088         const struct gs_can *dev = netdev_priv(netdev);
1089         int rc = 0;
1090
1091         if (!(dev->feature & GS_CAN_FEATURE_IDENTIFY))
1092                 return -EOPNOTSUPP;
1093
1094         switch (state) {
1095         case ETHTOOL_ID_ACTIVE:
1096                 rc = gs_usb_set_identify(netdev, GS_CAN_IDENTIFY_ON);
1097                 break;
1098         case ETHTOOL_ID_INACTIVE:
1099                 rc = gs_usb_set_identify(netdev, GS_CAN_IDENTIFY_OFF);
1100                 break;
1101         default:
1102                 break;
1103         }
1104
1105         return rc;
1106 }
1107
1108 static int gs_usb_get_ts_info(struct net_device *netdev,
1109                               struct ethtool_ts_info *info)
1110 {
1111         struct gs_can *dev = netdev_priv(netdev);
1112
1113         /* report if device supports HW timestamps */
1114         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1115                 return can_ethtool_op_get_ts_info_hwts(netdev, info);
1116
1117         return ethtool_op_get_ts_info(netdev, info);
1118 }
1119
1120 static const struct ethtool_ops gs_usb_ethtool_ops = {
1121         .set_phys_id = gs_usb_set_phys_id,
1122         .get_ts_info = gs_usb_get_ts_info,
1123 };
1124
1125 static int gs_usb_get_termination(struct net_device *netdev, u16 *term)
1126 {
1127         struct gs_can *dev = netdev_priv(netdev);
1128         struct gs_device_termination_state term_state;
1129         int rc;
1130
1131         rc = usb_control_msg_recv(dev->udev, 0, GS_USB_BREQ_GET_TERMINATION,
1132                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1133                                   dev->channel, 0,
1134                                   &term_state, sizeof(term_state), 1000,
1135                                   GFP_KERNEL);
1136         if (rc)
1137                 return rc;
1138
1139         if (term_state.state == cpu_to_le32(GS_CAN_TERMINATION_STATE_ON))
1140                 *term = GS_USB_TERMINATION_ENABLED;
1141         else
1142                 *term = GS_USB_TERMINATION_DISABLED;
1143
1144         return 0;
1145 }
1146
1147 static int gs_usb_set_termination(struct net_device *netdev, u16 term)
1148 {
1149         struct gs_can *dev = netdev_priv(netdev);
1150         struct gs_device_termination_state term_state;
1151
1152         if (term == GS_USB_TERMINATION_ENABLED)
1153                 term_state.state = cpu_to_le32(GS_CAN_TERMINATION_STATE_ON);
1154         else
1155                 term_state.state = cpu_to_le32(GS_CAN_TERMINATION_STATE_OFF);
1156
1157         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_SET_TERMINATION,
1158                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1159                                     dev->channel, 0,
1160                                     &term_state, sizeof(term_state), 1000,
1161                                     GFP_KERNEL);
1162 }
1163
1164 static const u16 gs_usb_termination_const[] = {
1165         GS_USB_TERMINATION_DISABLED,
1166         GS_USB_TERMINATION_ENABLED
1167 };
1168
1169 static struct gs_can *gs_make_candev(unsigned int channel,
1170                                      struct usb_interface *intf,
1171                                      struct gs_device_config *dconf)
1172 {
1173         struct gs_can *dev;
1174         struct net_device *netdev;
1175         int rc;
1176         struct gs_device_bt_const_extended bt_const_extended;
1177         struct gs_device_bt_const bt_const;
1178         u32 feature;
1179
1180         /* fetch bit timing constants */
1181         rc = usb_control_msg_recv(interface_to_usbdev(intf), 0,
1182                                   GS_USB_BREQ_BT_CONST,
1183                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1184                                   channel, 0, &bt_const, sizeof(bt_const), 1000,
1185                                   GFP_KERNEL);
1186
1187         if (rc) {
1188                 dev_err(&intf->dev,
1189                         "Couldn't get bit timing const for channel %d (%pe)\n",
1190                         channel, ERR_PTR(rc));
1191                 return ERR_PTR(rc);
1192         }
1193
1194         /* create netdev */
1195         netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS);
1196         if (!netdev) {
1197                 dev_err(&intf->dev, "Couldn't allocate candev\n");
1198                 return ERR_PTR(-ENOMEM);
1199         }
1200
1201         dev = netdev_priv(netdev);
1202
1203         netdev->netdev_ops = &gs_usb_netdev_ops;
1204         netdev->ethtool_ops = &gs_usb_ethtool_ops;
1205
1206         netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */
1207         netdev->dev_id = channel;
1208
1209         /* dev setup */
1210         strcpy(dev->bt_const.name, KBUILD_MODNAME);
1211         dev->bt_const.tseg1_min = le32_to_cpu(bt_const.tseg1_min);
1212         dev->bt_const.tseg1_max = le32_to_cpu(bt_const.tseg1_max);
1213         dev->bt_const.tseg2_min = le32_to_cpu(bt_const.tseg2_min);
1214         dev->bt_const.tseg2_max = le32_to_cpu(bt_const.tseg2_max);
1215         dev->bt_const.sjw_max = le32_to_cpu(bt_const.sjw_max);
1216         dev->bt_const.brp_min = le32_to_cpu(bt_const.brp_min);
1217         dev->bt_const.brp_max = le32_to_cpu(bt_const.brp_max);
1218         dev->bt_const.brp_inc = le32_to_cpu(bt_const.brp_inc);
1219
1220         dev->udev = interface_to_usbdev(intf);
1221         dev->netdev = netdev;
1222         dev->channel = channel;
1223
1224         init_usb_anchor(&dev->tx_submitted);
1225         atomic_set(&dev->active_tx_urbs, 0);
1226         spin_lock_init(&dev->tx_ctx_lock);
1227         for (rc = 0; rc < GS_MAX_TX_URBS; rc++) {
1228                 dev->tx_context[rc].dev = dev;
1229                 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS;
1230         }
1231
1232         /* can setup */
1233         dev->can.state = CAN_STATE_STOPPED;
1234         dev->can.clock.freq = le32_to_cpu(bt_const.fclk_can);
1235         dev->can.bittiming_const = &dev->bt_const;
1236         dev->can.do_set_bittiming = gs_usb_set_bittiming;
1237
1238         dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC;
1239
1240         feature = le32_to_cpu(bt_const.feature);
1241         dev->feature = FIELD_GET(GS_CAN_FEATURE_MASK, feature);
1242         if (feature & GS_CAN_FEATURE_LISTEN_ONLY)
1243                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY;
1244
1245         if (feature & GS_CAN_FEATURE_LOOP_BACK)
1246                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK;
1247
1248         if (feature & GS_CAN_FEATURE_TRIPLE_SAMPLE)
1249                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1250
1251         if (feature & GS_CAN_FEATURE_ONE_SHOT)
1252                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
1253
1254         if (feature & GS_CAN_FEATURE_FD) {
1255                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_FD;
1256                 /* The data bit timing will be overwritten, if
1257                  * GS_CAN_FEATURE_BT_CONST_EXT is set.
1258                  */
1259                 dev->can.data_bittiming_const = &dev->bt_const;
1260                 dev->can.do_set_data_bittiming = gs_usb_set_data_bittiming;
1261         }
1262
1263         if (feature & GS_CAN_FEATURE_TERMINATION) {
1264                 rc = gs_usb_get_termination(netdev, &dev->can.termination);
1265                 if (rc) {
1266                         dev->feature &= ~GS_CAN_FEATURE_TERMINATION;
1267
1268                         dev_info(&intf->dev,
1269                                  "Disabling termination support for channel %d (%pe)\n",
1270                                  channel, ERR_PTR(rc));
1271                 } else {
1272                         dev->can.termination_const = gs_usb_termination_const;
1273                         dev->can.termination_const_cnt = ARRAY_SIZE(gs_usb_termination_const);
1274                         dev->can.do_set_termination = gs_usb_set_termination;
1275                 }
1276         }
1277
1278         if (feature & GS_CAN_FEATURE_BERR_REPORTING)
1279                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_BERR_REPORTING;
1280
1281         if (feature & GS_CAN_FEATURE_GET_STATE)
1282                 dev->can.do_get_berr_counter = gs_usb_can_get_berr_counter;
1283
1284         /* The CANtact Pro from LinkLayer Labs is based on the
1285          * LPC54616 µC, which is affected by the NXP LPC USB transfer
1286          * erratum. However, the current firmware (version 2) doesn't
1287          * set the GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX bit. Set the
1288          * feature GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX to workaround
1289          * this issue.
1290          *
1291          * For the GS_USB_BREQ_DATA_BITTIMING USB control message the
1292          * CANtact Pro firmware uses a request value, which is already
1293          * used by the candleLight firmware for a different purpose
1294          * (GS_USB_BREQ_GET_USER_ID). Set the feature
1295          * GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO to workaround this
1296          * issue.
1297          */
1298         if (dev->udev->descriptor.idVendor == cpu_to_le16(USB_GS_USB_1_VENDOR_ID) &&
1299             dev->udev->descriptor.idProduct == cpu_to_le16(USB_GS_USB_1_PRODUCT_ID) &&
1300             dev->udev->manufacturer && dev->udev->product &&
1301             !strcmp(dev->udev->manufacturer, "LinkLayer Labs") &&
1302             !strcmp(dev->udev->product, "CANtact Pro") &&
1303             (le32_to_cpu(dconf->sw_version) <= 2))
1304                 dev->feature |= GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX |
1305                         GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO;
1306
1307         /* GS_CAN_FEATURE_IDENTIFY is only supported for sw_version > 1 */
1308         if (!(le32_to_cpu(dconf->sw_version) > 1 &&
1309               feature & GS_CAN_FEATURE_IDENTIFY))
1310                 dev->feature &= ~GS_CAN_FEATURE_IDENTIFY;
1311
1312         /* fetch extended bit timing constants if device has feature
1313          * GS_CAN_FEATURE_FD and GS_CAN_FEATURE_BT_CONST_EXT
1314          */
1315         if (feature & GS_CAN_FEATURE_FD &&
1316             feature & GS_CAN_FEATURE_BT_CONST_EXT) {
1317                 rc = usb_control_msg_recv(interface_to_usbdev(intf), 0,
1318                                           GS_USB_BREQ_BT_CONST_EXT,
1319                                           USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1320                                           channel, 0, &bt_const_extended,
1321                                           sizeof(bt_const_extended),
1322                                           1000, GFP_KERNEL);
1323                 if (rc) {
1324                         dev_err(&intf->dev,
1325                                 "Couldn't get extended bit timing const for channel %d (%pe)\n",
1326                                 channel, ERR_PTR(rc));
1327                         goto out_free_candev;
1328                 }
1329
1330                 strcpy(dev->data_bt_const.name, KBUILD_MODNAME);
1331                 dev->data_bt_const.tseg1_min = le32_to_cpu(bt_const_extended.dtseg1_min);
1332                 dev->data_bt_const.tseg1_max = le32_to_cpu(bt_const_extended.dtseg1_max);
1333                 dev->data_bt_const.tseg2_min = le32_to_cpu(bt_const_extended.dtseg2_min);
1334                 dev->data_bt_const.tseg2_max = le32_to_cpu(bt_const_extended.dtseg2_max);
1335                 dev->data_bt_const.sjw_max = le32_to_cpu(bt_const_extended.dsjw_max);
1336                 dev->data_bt_const.brp_min = le32_to_cpu(bt_const_extended.dbrp_min);
1337                 dev->data_bt_const.brp_max = le32_to_cpu(bt_const_extended.dbrp_max);
1338                 dev->data_bt_const.brp_inc = le32_to_cpu(bt_const_extended.dbrp_inc);
1339
1340                 dev->can.data_bittiming_const = &dev->data_bt_const;
1341         }
1342
1343         SET_NETDEV_DEV(netdev, &intf->dev);
1344
1345         rc = register_candev(dev->netdev);
1346         if (rc) {
1347                 dev_err(&intf->dev,
1348                         "Couldn't register candev for channel %d (%pe)\n",
1349                         channel, ERR_PTR(rc));
1350                 goto out_free_candev;
1351         }
1352
1353         return dev;
1354
1355 out_free_candev:
1356         free_candev(dev->netdev);
1357         return ERR_PTR(rc);
1358 }
1359
1360 static void gs_destroy_candev(struct gs_can *dev)
1361 {
1362         unregister_candev(dev->netdev);
1363         usb_kill_anchored_urbs(&dev->tx_submitted);
1364         free_candev(dev->netdev);
1365 }
1366
1367 static int gs_usb_probe(struct usb_interface *intf,
1368                         const struct usb_device_id *id)
1369 {
1370         struct usb_device *udev = interface_to_usbdev(intf);
1371         struct gs_host_frame *hf;
1372         struct gs_usb *dev;
1373         struct gs_host_config hconf = {
1374                 .byte_order = cpu_to_le32(0x0000beef),
1375         };
1376         struct gs_device_config dconf;
1377         unsigned int icount, i;
1378         int rc;
1379
1380         /* send host config */
1381         rc = usb_control_msg_send(udev, 0,
1382                                   GS_USB_BREQ_HOST_FORMAT,
1383                                   USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1384                                   1, intf->cur_altsetting->desc.bInterfaceNumber,
1385                                   &hconf, sizeof(hconf), 1000,
1386                                   GFP_KERNEL);
1387         if (rc) {
1388                 dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", rc);
1389                 return rc;
1390         }
1391
1392         /* read device config */
1393         rc = usb_control_msg_recv(udev, 0,
1394                                   GS_USB_BREQ_DEVICE_CONFIG,
1395                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1396                                   1, intf->cur_altsetting->desc.bInterfaceNumber,
1397                                   &dconf, sizeof(dconf), 1000,
1398                                   GFP_KERNEL);
1399         if (rc) {
1400                 dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n",
1401                         rc);
1402                 return rc;
1403         }
1404
1405         icount = dconf.icount + 1;
1406         dev_info(&intf->dev, "Configuring for %u interfaces\n", icount);
1407
1408         if (icount > GS_MAX_INTF) {
1409                 dev_err(&intf->dev,
1410                         "Driver cannot handle more that %u CAN interfaces\n",
1411                         GS_MAX_INTF);
1412                 return -EINVAL;
1413         }
1414
1415         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1416         if (!dev)
1417                 return -ENOMEM;
1418
1419         init_usb_anchor(&dev->rx_submitted);
1420
1421         usb_set_intfdata(intf, dev);
1422         dev->udev = udev;
1423
1424         for (i = 0; i < icount; i++) {
1425                 unsigned int hf_size_rx = 0;
1426
1427                 dev->canch[i] = gs_make_candev(i, intf, &dconf);
1428                 if (IS_ERR_OR_NULL(dev->canch[i])) {
1429                         /* save error code to return later */
1430                         rc = PTR_ERR(dev->canch[i]);
1431
1432                         /* on failure destroy previously created candevs */
1433                         icount = i;
1434                         for (i = 0; i < icount; i++)
1435                                 gs_destroy_candev(dev->canch[i]);
1436
1437                         usb_kill_anchored_urbs(&dev->rx_submitted);
1438                         kfree(dev);
1439                         return rc;
1440                 }
1441                 dev->canch[i]->parent = dev;
1442
1443                 /* set RX packet size based on FD and if hardware
1444                  * timestamps are supported.
1445                  */
1446                 if (dev->canch[i]->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
1447                         if (dev->canch[i]->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1448                                 hf_size_rx = struct_size(hf, canfd_ts, 1);
1449                         else
1450                                 hf_size_rx = struct_size(hf, canfd, 1);
1451                 } else {
1452                         if (dev->canch[i]->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1453                                 hf_size_rx = struct_size(hf, classic_can_ts, 1);
1454                         else
1455                                 hf_size_rx = struct_size(hf, classic_can, 1);
1456                 }
1457                 dev->hf_size_rx = max(dev->hf_size_rx, hf_size_rx);
1458         }
1459
1460         return 0;
1461 }
1462
1463 static void gs_usb_disconnect(struct usb_interface *intf)
1464 {
1465         struct gs_usb *dev = usb_get_intfdata(intf);
1466         unsigned int i;
1467
1468         usb_set_intfdata(intf, NULL);
1469
1470         if (!dev) {
1471                 dev_err(&intf->dev, "Disconnect (nodata)\n");
1472                 return;
1473         }
1474
1475         for (i = 0; i < GS_MAX_INTF; i++)
1476                 if (dev->canch[i])
1477                         gs_destroy_candev(dev->canch[i]);
1478
1479         usb_kill_anchored_urbs(&dev->rx_submitted);
1480         kfree(dev);
1481 }
1482
1483 static const struct usb_device_id gs_usb_table[] = {
1484         { USB_DEVICE_INTERFACE_NUMBER(USB_GS_USB_1_VENDOR_ID,
1485                                       USB_GS_USB_1_PRODUCT_ID, 0) },
1486         { USB_DEVICE_INTERFACE_NUMBER(USB_CANDLELIGHT_VENDOR_ID,
1487                                       USB_CANDLELIGHT_PRODUCT_ID, 0) },
1488         { USB_DEVICE_INTERFACE_NUMBER(USB_CES_CANEXT_FD_VENDOR_ID,
1489                                       USB_CES_CANEXT_FD_PRODUCT_ID, 0) },
1490         { USB_DEVICE_INTERFACE_NUMBER(USB_ABE_CANDEBUGGER_FD_VENDOR_ID,
1491                                       USB_ABE_CANDEBUGGER_FD_PRODUCT_ID, 0) },
1492         {} /* Terminating entry */
1493 };
1494
1495 MODULE_DEVICE_TABLE(usb, gs_usb_table);
1496
1497 static struct usb_driver gs_usb_driver = {
1498         .name = KBUILD_MODNAME,
1499         .probe = gs_usb_probe,
1500         .disconnect = gs_usb_disconnect,
1501         .id_table = gs_usb_table,
1502 };
1503
1504 module_usb_driver(gs_usb_driver);
1505
1506 MODULE_AUTHOR("Maximilian Schneider <mws@schneidersoft.net>");
1507 MODULE_DESCRIPTION(
1508 "Socket CAN device driver for Geschwister Schneider Technologie-, "
1509 "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces\n"
1510 "and bytewerk.org candleLight USB CAN interfaces.");
1511 MODULE_LICENSE("GPL v2");