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  * Copyright (c) 2023 Pengutronix, Marc Kleine-Budde <[email protected]>
   9  *
  10  * Many thanks to all socketcan devs!
  11  */
  12
  13 #include <linux/bitfield.h>
  14 #include <linux/clocksource.h>
  15 #include <linux/ethtool.h>
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/signal.h>
  20 #include <linux/timecounter.h>
  21 #include <linux/units.h>
  22 #include <linux/usb.h>
  23 #include <linux/workqueue.h>
  24
  25 #include <linux/can.h>
  26 #include <linux/can/dev.h>
  27 #include <linux/can/error.h>
  28 #include <linux/can/rx-offload.h>
  29
  30 /* Device specific constants */
  31 #define USB_GS_USB_1_VENDOR_ID 0x1d50
  32 #define USB_GS_USB_1_PRODUCT_ID 0x606f
  33
  34 #define USB_CANDLELIGHT_VENDOR_ID 0x1209
  35 #define USB_CANDLELIGHT_PRODUCT_ID 0x2323
  36
  37 #define USB_CES_CANEXT_FD_VENDOR_ID 0x1cd2
  38 #define USB_CES_CANEXT_FD_PRODUCT_ID 0x606f
  39
  40 #define USB_ABE_CANDEBUGGER_FD_VENDOR_ID 0x16d0
  41 #define USB_ABE_CANDEBUGGER_FD_PRODUCT_ID 0x10b8
  42
  43 #define USB_XYLANTA_SAINT3_VENDOR_ID 0x16d0
  44 #define USB_XYLANTA_SAINT3_PRODUCT_ID 0x0f30
  45
  46 #define GS_USB_ENDPOINT_IN 1
  47 #define GS_USB_ENDPOINT_OUT 2
  48
  49 /* Timestamp 32 bit timer runs at 1 MHz (1 µs tick). Worker accounts
  50  * for timer overflow (will be after ~71 minutes)
  51  */
  52 #define GS_USB_TIMESTAMP_TIMER_HZ (1 * HZ_PER_MHZ)
  53 #define GS_USB_TIMESTAMP_WORK_DELAY_SEC 1800
  54 static_assert(GS_USB_TIMESTAMP_WORK_DELAY_SEC <
  55               CYCLECOUNTER_MASK(32) / GS_USB_TIMESTAMP_TIMER_HZ / 2);
  56
  57 /* Device specific constants */
  58 enum gs_usb_breq {
  59         GS_USB_BREQ_HOST_FORMAT = 0,
  60         GS_USB_BREQ_BITTIMING,
  61         GS_USB_BREQ_MODE,
  62         GS_USB_BREQ_BERR,
  63         GS_USB_BREQ_BT_CONST,
  64         GS_USB_BREQ_DEVICE_CONFIG,
  65         GS_USB_BREQ_TIMESTAMP,
  66         GS_USB_BREQ_IDENTIFY,
  67         GS_USB_BREQ_GET_USER_ID,
  68         GS_USB_BREQ_QUIRK_CANTACT_PRO_DATA_BITTIMING = GS_USB_BREQ_GET_USER_ID,
  69         GS_USB_BREQ_SET_USER_ID,
  70         GS_USB_BREQ_DATA_BITTIMING,
  71         GS_USB_BREQ_BT_CONST_EXT,
  72         GS_USB_BREQ_SET_TERMINATION,
  73         GS_USB_BREQ_GET_TERMINATION,
  74         GS_USB_BREQ_GET_STATE,
  75 };
  76
  77 enum gs_can_mode {
  78         /* reset a channel. turns it off */
  79         GS_CAN_MODE_RESET = 0,
  80         /* starts a channel */
  81         GS_CAN_MODE_START
  82 };
  83
  84 enum gs_can_state {
  85         GS_CAN_STATE_ERROR_ACTIVE = 0,
  86         GS_CAN_STATE_ERROR_WARNING,
  87         GS_CAN_STATE_ERROR_PASSIVE,
  88         GS_CAN_STATE_BUS_OFF,
  89         GS_CAN_STATE_STOPPED,
  90         GS_CAN_STATE_SLEEPING
  91 };
  92
  93 enum gs_can_identify_mode {
  94         GS_CAN_IDENTIFY_OFF = 0,
  95         GS_CAN_IDENTIFY_ON
  96 };
  97
  98 enum gs_can_termination_state {
  99         GS_CAN_TERMINATION_STATE_OFF = 0,
 100         GS_CAN_TERMINATION_STATE_ON
 101 };
 102
 103 #define GS_USB_TERMINATION_DISABLED CAN_TERMINATION_DISABLED
 104 #define GS_USB_TERMINATION_ENABLED 120
 105
 106 /* data types passed between host and device */
 107
 108 /* The firmware on the original USB2CAN by Geschwister Schneider
 109  * Technologie Entwicklungs- und Vertriebs UG exchanges all data
 110  * between the host and the device in host byte order. This is done
 111  * with the struct gs_host_config::byte_order member, which is sent
 112  * first to indicate the desired byte order.
 113  *
 114  * The widely used open source firmware candleLight doesn't support
 115  * this feature and exchanges the data in little endian byte order.
 116  */
 117 struct gs_host_config {
 118         __le32 byte_order;
 119 } __packed;
 120
 121 struct gs_device_config {
 122         u8 reserved1;
 123         u8 reserved2;
 124         u8 reserved3;
 125         u8 icount;
 126         __le32 sw_version;
 127         __le32 hw_version;
 128 } __packed;
 129
 130 #define GS_CAN_MODE_NORMAL 0
 131 #define GS_CAN_MODE_LISTEN_ONLY BIT(0)
 132 #define GS_CAN_MODE_LOOP_BACK BIT(1)
 133 #define GS_CAN_MODE_TRIPLE_SAMPLE BIT(2)
 134 #define GS_CAN_MODE_ONE_SHOT BIT(3)
 135 #define GS_CAN_MODE_HW_TIMESTAMP BIT(4)
 136 /* GS_CAN_FEATURE_IDENTIFY BIT(5) */
 137 /* GS_CAN_FEATURE_USER_ID BIT(6) */
 138 #define GS_CAN_MODE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
 139 #define GS_CAN_MODE_FD BIT(8)
 140 /* GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9) */
 141 /* GS_CAN_FEATURE_BT_CONST_EXT BIT(10) */
 142 /* GS_CAN_FEATURE_TERMINATION BIT(11) */
 143 #define GS_CAN_MODE_BERR_REPORTING BIT(12)
 144 /* GS_CAN_FEATURE_GET_STATE BIT(13) */
 145
 146 struct gs_device_mode {
 147         __le32 mode;
 148         __le32 flags;
 149 } __packed;
 150
 151 struct gs_device_state {
 152         __le32 state;
 153         __le32 rxerr;
 154         __le32 txerr;
 155 } __packed;
 156
 157 struct gs_device_bittiming {
 158         __le32 prop_seg;
 159         __le32 phase_seg1;
 160         __le32 phase_seg2;
 161         __le32 sjw;
 162         __le32 brp;
 163 } __packed;
 164
 165 struct gs_identify_mode {
 166         __le32 mode;
 167 } __packed;
 168
 169 struct gs_device_termination_state {
 170         __le32 state;
 171 } __packed;
 172
 173 #define GS_CAN_FEATURE_LISTEN_ONLY BIT(0)
 174 #define GS_CAN_FEATURE_LOOP_BACK BIT(1)
 175 #define GS_CAN_FEATURE_TRIPLE_SAMPLE BIT(2)
 176 #define GS_CAN_FEATURE_ONE_SHOT BIT(3)
 177 #define GS_CAN_FEATURE_HW_TIMESTAMP BIT(4)
 178 #define GS_CAN_FEATURE_IDENTIFY BIT(5)
 179 #define GS_CAN_FEATURE_USER_ID BIT(6)
 180 #define GS_CAN_FEATURE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
 181 #define GS_CAN_FEATURE_FD BIT(8)
 182 #define GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9)
 183 #define GS_CAN_FEATURE_BT_CONST_EXT BIT(10)
 184 #define GS_CAN_FEATURE_TERMINATION BIT(11)
 185 #define GS_CAN_FEATURE_BERR_REPORTING BIT(12)
 186 #define GS_CAN_FEATURE_GET_STATE BIT(13)
 187 #define GS_CAN_FEATURE_MASK GENMASK(13, 0)
 188
 189 /* internal quirks - keep in GS_CAN_FEATURE space for now */
 190
 191 /* CANtact Pro original firmware:
 192  * BREQ DATA_BITTIMING overlaps with GET_USER_ID
 193  */
 194 #define GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO BIT(31)
 195
 196 struct gs_device_bt_const {
 197         __le32 feature;
 198         __le32 fclk_can;
 199         __le32 tseg1_min;
 200         __le32 tseg1_max;
 201         __le32 tseg2_min;
 202         __le32 tseg2_max;
 203         __le32 sjw_max;
 204         __le32 brp_min;
 205         __le32 brp_max;
 206         __le32 brp_inc;
 207 } __packed;
 208
 209 struct gs_device_bt_const_extended {
 210         __le32 feature;
 211         __le32 fclk_can;
 212         __le32 tseg1_min;
 213         __le32 tseg1_max;
 214         __le32 tseg2_min;
 215         __le32 tseg2_max;
 216         __le32 sjw_max;
 217         __le32 brp_min;
 218         __le32 brp_max;
 219         __le32 brp_inc;
 220
 221         __le32 dtseg1_min;
 222         __le32 dtseg1_max;
 223         __le32 dtseg2_min;
 224         __le32 dtseg2_max;
 225         __le32 dsjw_max;
 226         __le32 dbrp_min;
 227         __le32 dbrp_max;
 228         __le32 dbrp_inc;
 229 } __packed;
 230
 231 #define GS_CAN_FLAG_OVERFLOW BIT(0)
 232 #define GS_CAN_FLAG_FD BIT(1)
 233 #define GS_CAN_FLAG_BRS BIT(2)
 234 #define GS_CAN_FLAG_ESI BIT(3)
 235
 236 struct classic_can {
 237         u8 data[8];
 238 } __packed;
 239
 240 struct classic_can_ts {
 241         u8 data[8];
 242         __le32 timestamp_us;
 243 } __packed;
 244
 245 struct classic_can_quirk {
 246         u8 data[8];
 247         u8 quirk;
 248 } __packed;
 249
 250 struct canfd {
 251         u8 data[64];
 252 } __packed;
 253
 254 struct canfd_ts {
 255         u8 data[64];
 256         __le32 timestamp_us;
 257 } __packed;
 258
 259 struct canfd_quirk {
 260         u8 data[64];
 261         u8 quirk;
 262 } __packed;
 263
 264 struct gs_host_frame {
 265         u32 echo_id;
 266         __le32 can_id;
 267
 268         u8 can_dlc;
 269         u8 channel;
 270         u8 flags;
 271         u8 reserved;
 272
 273         union {
 274                 DECLARE_FLEX_ARRAY(struct classic_can, classic_can);
 275                 DECLARE_FLEX_ARRAY(struct classic_can_ts, classic_can_ts);
 276                 DECLARE_FLEX_ARRAY(struct classic_can_quirk, classic_can_quirk);
 277                 DECLARE_FLEX_ARRAY(struct canfd, canfd);
 278                 DECLARE_FLEX_ARRAY(struct canfd_ts, canfd_ts);
 279                 DECLARE_FLEX_ARRAY(struct canfd_quirk, canfd_quirk);
 280         };
 281 } __packed;
 282 /* The GS USB devices make use of the same flags and masks as in
 283  * linux/can.h and linux/can/error.h, and no additional mapping is necessary.
 284  */
 285
 286 /* Only send a max of GS_MAX_TX_URBS frames per channel at a time. */
 287 #define GS_MAX_TX_URBS 10
 288 /* Only launch a max of GS_MAX_RX_URBS usb requests at a time. */
 289 #define GS_MAX_RX_URBS 30
 290 #define GS_NAPI_WEIGHT 32
 291
 292 /* Maximum number of interfaces the driver supports per device.
 293  * Current hardware only supports 3 interfaces. The future may vary.
 294  */
 295 #define GS_MAX_INTF 3
 296
 297 struct gs_tx_context {
 298         struct gs_can *dev;
 299         unsigned int echo_id;
 300 };
 301
 302 struct gs_can {
 303         struct can_priv can; /* must be the first member */
 304
 305         struct can_rx_offload offload;
 306         struct gs_usb *parent;
 307
 308         struct net_device *netdev;
 309         struct usb_device *udev;
 310
 311         struct can_bittiming_const bt_const, data_bt_const;
 312         unsigned int channel;   /* channel number */
 313
 314         u32 feature;
 315         unsigned int hf_size_tx;
 316
 317         /* This lock prevents a race condition between xmit and receive. */
 318         spinlock_t tx_ctx_lock;
 319         struct gs_tx_context tx_context[GS_MAX_TX_URBS];
 320
 321         struct usb_anchor tx_submitted;
 322         atomic_t active_tx_urbs;
 323 };
 324
 325 /* usb interface struct */
 326 struct gs_usb {
 327         struct gs_can *canch[GS_MAX_INTF];
 328         struct usb_anchor rx_submitted;
 329         struct usb_device *udev;
 330
 331         /* time counter for hardware timestamps */
 332         struct cyclecounter cc;
 333         struct timecounter tc;
 334         spinlock_t tc_lock; /* spinlock to guard access tc->cycle_last */
 335         struct delayed_work timestamp;
 336
 337         unsigned int hf_size_rx;
 338         u8 active_channels;
 339 };
 340
 341 /* 'allocate' a tx context.
 342  * returns a valid tx context or NULL if there is no space.
 343  */
 344 static struct gs_tx_context *gs_alloc_tx_context(struct gs_can *dev)
 345 {
 346         int i = 0;
 347         unsigned long flags;
 348
 349         spin_lock_irqsave(&dev->tx_ctx_lock, flags);
 350
 351         for (; i < GS_MAX_TX_URBS; i++) {
 352                 if (dev->tx_context[i].echo_id == GS_MAX_TX_URBS) {
 353                         dev->tx_context[i].echo_id = i;
 354                         spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 355                         return &dev->tx_context[i];
 356                 }
 357         }
 358
 359         spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 360         return NULL;
 361 }
 362
 363 /* releases a tx context
 364  */
 365 static void gs_free_tx_context(struct gs_tx_context *txc)
 366 {
 367         txc->echo_id = GS_MAX_TX_URBS;
 368 }
 369
 370 /* Get a tx context by id.
 371  */
 372 static struct gs_tx_context *gs_get_tx_context(struct gs_can *dev,
 373                                                unsigned int id)
 374 {
 375         unsigned long flags;
 376
 377         if (id < GS_MAX_TX_URBS) {
 378                 spin_lock_irqsave(&dev->tx_ctx_lock, flags);
 379                 if (dev->tx_context[id].echo_id == id) {
 380                         spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 381                         return &dev->tx_context[id];
 382                 }
 383                 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
 384         }
 385         return NULL;
 386 }
 387
 388 static int gs_cmd_reset(struct gs_can *dev)
 389 {
 390         struct gs_device_mode dm = {
 391                 .mode = cpu_to_le32(GS_CAN_MODE_RESET),
 392         };
 393
 394         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_MODE,
 395                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 396                                     dev->channel, 0, &dm, sizeof(dm), 1000,
 397                                     GFP_KERNEL);
 398 }
 399
 400 static inline int gs_usb_get_timestamp(const struct gs_usb *parent,
 401                                        u32 *timestamp_p)
 402 {
 403         __le32 timestamp;
 404         int rc;
 405
 406         rc = usb_control_msg_recv(parent->udev, 0, GS_USB_BREQ_TIMESTAMP,
 407                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 408                                   0, 0,
 409                                   &timestamp, sizeof(timestamp),
 410                                   USB_CTRL_GET_TIMEOUT,
 411                                   GFP_KERNEL);
 412         if (rc)
 413                 return rc;
 414
 415         *timestamp_p = le32_to_cpu(timestamp);
 416
 417         return 0;
 418 }
 419
 420 static u64 gs_usb_timestamp_read(const struct cyclecounter *cc) __must_hold(&dev->tc_lock)
 421 {
 422         struct gs_usb *parent = container_of(cc, struct gs_usb, cc);
 423         u32 timestamp = 0;
 424         int err;
 425
 426         lockdep_assert_held(&parent->tc_lock);
 427
 428         /* drop lock for synchronous USB transfer */
 429         spin_unlock_bh(&parent->tc_lock);
 430         err = gs_usb_get_timestamp(parent, &timestamp);
 431         spin_lock_bh(&parent->tc_lock);
 432         if (err)
 433                 dev_err(&parent->udev->dev,
 434                         "Error %d while reading timestamp. HW timestamps may be inaccurate.",
 435                         err);
 436
 437         return timestamp;
 438 }
 439
 440 static void gs_usb_timestamp_work(struct work_struct *work)
 441 {
 442         struct delayed_work *delayed_work = to_delayed_work(work);
 443         struct gs_usb *parent;
 444
 445         parent = container_of(delayed_work, struct gs_usb, timestamp);
 446         spin_lock_bh(&parent->tc_lock);
 447         timecounter_read(&parent->tc);
 448         spin_unlock_bh(&parent->tc_lock);
 449
 450         schedule_delayed_work(&parent->timestamp,
 451                               GS_USB_TIMESTAMP_WORK_DELAY_SEC * HZ);
 452 }
 453
 454 static void gs_usb_skb_set_timestamp(struct gs_can *dev,
 455                                      struct sk_buff *skb, u32 timestamp)
 456 {
 457         struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
 458         struct gs_usb *parent = dev->parent;
 459         u64 ns;
 460
 461         spin_lock_bh(&parent->tc_lock);
 462         ns = timecounter_cyc2time(&parent->tc, timestamp);
 463         spin_unlock_bh(&parent->tc_lock);
 464
 465         hwtstamps->hwtstamp = ns_to_ktime(ns);
 466 }
 467
 468 static void gs_usb_timestamp_init(struct gs_usb *parent)
 469 {
 470         struct cyclecounter *cc = &parent->cc;
 471
 472         cc->read = gs_usb_timestamp_read;
 473         cc->mask = CYCLECOUNTER_MASK(32);
 474         cc->shift = 32 - bits_per(NSEC_PER_SEC / GS_USB_TIMESTAMP_TIMER_HZ);
 475         cc->mult = clocksource_hz2mult(GS_USB_TIMESTAMP_TIMER_HZ, cc->shift);
 476
 477         spin_lock_init(&parent->tc_lock);
 478         spin_lock_bh(&parent->tc_lock);
 479         timecounter_init(&parent->tc, &parent->cc, ktime_get_real_ns());
 480         spin_unlock_bh(&parent->tc_lock);
 481
 482         INIT_DELAYED_WORK(&parent->timestamp, gs_usb_timestamp_work);
 483         schedule_delayed_work(&parent->timestamp,
 484                               GS_USB_TIMESTAMP_WORK_DELAY_SEC * HZ);
 485 }
 486
 487 static void gs_usb_timestamp_stop(struct gs_usb *parent)
 488 {
 489         cancel_delayed_work_sync(&parent->timestamp);
 490 }
 491
 492 static void gs_update_state(struct gs_can *dev, struct can_frame *cf)
 493 {
 494         struct can_device_stats *can_stats = &dev->can.can_stats;
 495
 496         if (cf->can_id & CAN_ERR_RESTARTED) {
 497                 dev->can.state = CAN_STATE_ERROR_ACTIVE;
 498                 can_stats->restarts++;
 499         } else if (cf->can_id & CAN_ERR_BUSOFF) {
 500                 dev->can.state = CAN_STATE_BUS_OFF;
 501                 can_stats->bus_off++;
 502         } else if (cf->can_id & CAN_ERR_CRTL) {
 503                 if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) ||
 504                     (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) {
 505                         dev->can.state = CAN_STATE_ERROR_WARNING;
 506                         can_stats->error_warning++;
 507                 } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) ||
 508                            (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) {
 509                         dev->can.state = CAN_STATE_ERROR_PASSIVE;
 510                         can_stats->error_passive++;
 511                 } else {
 512                         dev->can.state = CAN_STATE_ERROR_ACTIVE;
 513                 }
 514         }
 515 }
 516
 517 static u32 gs_usb_set_timestamp(struct gs_can *dev, struct sk_buff *skb,
 518                                 const struct gs_host_frame *hf)
 519 {
 520         u32 timestamp;
 521
 522         if (hf->flags & GS_CAN_FLAG_FD)
 523                 timestamp = le32_to_cpu(hf->canfd_ts->timestamp_us);
 524         else
 525                 timestamp = le32_to_cpu(hf->classic_can_ts->timestamp_us);
 526
 527         if (skb)
 528                 gs_usb_skb_set_timestamp(dev, skb, timestamp);
 529
 530         return timestamp;
 531 }
 532
 533 static void gs_usb_rx_offload(struct gs_can *dev, struct sk_buff *skb,
 534                               const struct gs_host_frame *hf)
 535 {
 536         struct can_rx_offload *offload = &dev->offload;
 537         int rc;
 538
 539         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP) {
 540                 const u32 ts = gs_usb_set_timestamp(dev, skb, hf);
 541
 542                 rc = can_rx_offload_queue_timestamp(offload, skb, ts);
 543         } else {
 544                 rc = can_rx_offload_queue_tail(offload, skb);
 545         }
 546
 547         if (rc)
 548                 dev->netdev->stats.rx_fifo_errors++;
 549 }
 550
 551 static unsigned int
 552 gs_usb_get_echo_skb(struct gs_can *dev, struct sk_buff *skb,
 553                     const struct gs_host_frame *hf)
 554 {
 555         struct can_rx_offload *offload = &dev->offload;
 556         const u32 echo_id = hf->echo_id;
 557         unsigned int len;
 558
 559         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP) {
 560                 const u32 ts = gs_usb_set_timestamp(dev, skb, hf);
 561
 562                 len = can_rx_offload_get_echo_skb_queue_timestamp(offload, echo_id,
 563                                                                   ts, NULL);
 564         } else {
 565                 len = can_rx_offload_get_echo_skb_queue_tail(offload, echo_id,
 566                                                              NULL);
 567         }
 568
 569         return len;
 570 }
 571
 572 static void gs_usb_receive_bulk_callback(struct urb *urb)
 573 {
 574         struct gs_usb *parent = urb->context;
 575         struct gs_can *dev;
 576         struct net_device *netdev;
 577         int rc;
 578         struct net_device_stats *stats;
 579         struct gs_host_frame *hf = urb->transfer_buffer;
 580         struct gs_tx_context *txc;
 581         struct can_frame *cf;
 582         struct canfd_frame *cfd;
 583         struct sk_buff *skb;
 584
 585         BUG_ON(!parent);
 586
 587         switch (urb->status) {
 588         case 0: /* success */
 589                 break;
 590         case -ENOENT:
 591         case -ESHUTDOWN:
 592                 return;
 593         default:
 594                 /* do not resubmit aborted urbs. eg: when device goes down */
 595                 return;
 596         }
 597
 598         /* device reports out of range channel id */
 599         if (hf->channel >= GS_MAX_INTF)
 600                 goto device_detach;
 601
 602         dev = parent->canch[hf->channel];
 603
 604         netdev = dev->netdev;
 605         stats = &netdev->stats;
 606
 607         if (!netif_device_present(netdev))
 608                 return;
 609
 610         if (!netif_running(netdev))
 611                 goto resubmit_urb;
 612
 613         if (hf->echo_id == -1) { /* normal rx */
 614                 if (hf->flags & GS_CAN_FLAG_FD) {
 615                         skb = alloc_canfd_skb(netdev, &cfd);
 616                         if (!skb)
 617                                 return;
 618
 619                         cfd->can_id = le32_to_cpu(hf->can_id);
 620                         cfd->len = can_fd_dlc2len(hf->can_dlc);
 621                         if (hf->flags & GS_CAN_FLAG_BRS)
 622                                 cfd->flags |= CANFD_BRS;
 623                         if (hf->flags & GS_CAN_FLAG_ESI)
 624                                 cfd->flags |= CANFD_ESI;
 625
 626                         memcpy(cfd->data, hf->canfd->data, cfd->len);
 627                 } else {
 628                         skb = alloc_can_skb(netdev, &cf);
 629                         if (!skb)
 630                                 return;
 631
 632                         cf->can_id = le32_to_cpu(hf->can_id);
 633                         can_frame_set_cc_len(cf, hf->can_dlc, dev->can.ctrlmode);
 634
 635                         memcpy(cf->data, hf->classic_can->data, 8);
 636
 637                         /* ERROR frames tell us information about the controller */
 638                         if (le32_to_cpu(hf->can_id) & CAN_ERR_FLAG)
 639                                 gs_update_state(dev, cf);
 640                 }
 641
 642                 gs_usb_rx_offload(dev, skb, hf);
 643         } else { /* echo_id == hf->echo_id */
 644                 if (hf->echo_id >= GS_MAX_TX_URBS) {
 645                         netdev_err(netdev,
 646                                    "Unexpected out of range echo id %u\n",
 647                                    hf->echo_id);
 648                         goto resubmit_urb;
 649                 }
 650
 651                 txc = gs_get_tx_context(dev, hf->echo_id);
 652
 653                 /* bad devices send bad echo_ids. */
 654                 if (!txc) {
 655                         netdev_err(netdev,
 656                                    "Unexpected unused echo id %u\n",
 657                                    hf->echo_id);
 658                         goto resubmit_urb;
 659                 }
 660
 661                 skb = dev->can.echo_skb[hf->echo_id];
 662                 stats->tx_packets++;
 663                 stats->tx_bytes += gs_usb_get_echo_skb(dev, skb, hf);
 664                 gs_free_tx_context(txc);
 665
 666                 atomic_dec(&dev->active_tx_urbs);
 667
 668                 netif_wake_queue(netdev);
 669         }
 670
 671         if (hf->flags & GS_CAN_FLAG_OVERFLOW) {
 672                 stats->rx_over_errors++;
 673                 stats->rx_errors++;
 674
 675                 skb = alloc_can_err_skb(netdev, &cf);
 676                 if (!skb)
 677                         goto resubmit_urb;
 678
 679                 cf->can_id |= CAN_ERR_CRTL;
 680                 cf->len = CAN_ERR_DLC;
 681                 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
 682
 683                 gs_usb_rx_offload(dev, skb, hf);
 684         }
 685
 686         can_rx_offload_irq_finish(&dev->offload);
 687
 688 resubmit_urb:
 689         usb_fill_bulk_urb(urb, parent->udev,
 690                           usb_rcvbulkpipe(parent->udev, GS_USB_ENDPOINT_IN),
 691                           hf, dev->parent->hf_size_rx,
 692                           gs_usb_receive_bulk_callback, parent);
 693
 694         rc = usb_submit_urb(urb, GFP_ATOMIC);
 695
 696         /* USB failure take down all interfaces */
 697         if (rc == -ENODEV) {
 698 device_detach:
 699                 for (rc = 0; rc < GS_MAX_INTF; rc++) {
 700                         if (parent->canch[rc])
 701                                 netif_device_detach(parent->canch[rc]->netdev);
 702                 }
 703         }
 704 }
 705
 706 static int gs_usb_set_bittiming(struct net_device *netdev)
 707 {
 708         struct gs_can *dev = netdev_priv(netdev);
 709         struct can_bittiming *bt = &dev->can.bittiming;
 710         struct gs_device_bittiming dbt = {
 711                 .prop_seg = cpu_to_le32(bt->prop_seg),
 712                 .phase_seg1 = cpu_to_le32(bt->phase_seg1),
 713                 .phase_seg2 = cpu_to_le32(bt->phase_seg2),
 714                 .sjw = cpu_to_le32(bt->sjw),
 715                 .brp = cpu_to_le32(bt->brp),
 716         };
 717
 718         /* request bit timings */
 719         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_BITTIMING,
 720                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 721                                     dev->channel, 0, &dbt, sizeof(dbt), 1000,
 722                                     GFP_KERNEL);
 723 }
 724
 725 static int gs_usb_set_data_bittiming(struct net_device *netdev)
 726 {
 727         struct gs_can *dev = netdev_priv(netdev);
 728         struct can_bittiming *bt = &dev->can.data_bittiming;
 729         struct gs_device_bittiming dbt = {
 730                 .prop_seg = cpu_to_le32(bt->prop_seg),
 731                 .phase_seg1 = cpu_to_le32(bt->phase_seg1),
 732                 .phase_seg2 = cpu_to_le32(bt->phase_seg2),
 733                 .sjw = cpu_to_le32(bt->sjw),
 734                 .brp = cpu_to_le32(bt->brp),
 735         };
 736         u8 request = GS_USB_BREQ_DATA_BITTIMING;
 737
 738         if (dev->feature & GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO)
 739                 request = GS_USB_BREQ_QUIRK_CANTACT_PRO_DATA_BITTIMING;
 740
 741         /* request data bit timings */
 742         return usb_control_msg_send(dev->udev, 0, request,
 743                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 744                                     dev->channel, 0, &dbt, sizeof(dbt), 1000,
 745                                     GFP_KERNEL);
 746 }
 747
 748 static void gs_usb_xmit_callback(struct urb *urb)
 749 {
 750         struct gs_tx_context *txc = urb->context;
 751         struct gs_can *dev = txc->dev;
 752         struct net_device *netdev = dev->netdev;
 753
 754         if (urb->status)
 755                 netdev_info(netdev, "usb xmit fail %u\n", txc->echo_id);
 756 }
 757
 758 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb,
 759                                      struct net_device *netdev)
 760 {
 761         struct gs_can *dev = netdev_priv(netdev);
 762         struct net_device_stats *stats = &dev->netdev->stats;
 763         struct urb *urb;
 764         struct gs_host_frame *hf;
 765         struct can_frame *cf;
 766         struct canfd_frame *cfd;
 767         int rc;
 768         unsigned int idx;
 769         struct gs_tx_context *txc;
 770
 771         if (can_dev_dropped_skb(netdev, skb))
 772                 return NETDEV_TX_OK;
 773
 774         /* find an empty context to keep track of transmission */
 775         txc = gs_alloc_tx_context(dev);
 776         if (!txc)
 777                 return NETDEV_TX_BUSY;
 778
 779         /* create a URB, and a buffer for it */
 780         urb = usb_alloc_urb(0, GFP_ATOMIC);
 781         if (!urb)
 782                 goto nomem_urb;
 783
 784         hf = kmalloc(dev->hf_size_tx, GFP_ATOMIC);
 785         if (!hf)
 786                 goto nomem_hf;
 787
 788         idx = txc->echo_id;
 789
 790         if (idx >= GS_MAX_TX_URBS) {
 791                 netdev_err(netdev, "Invalid tx context %u\n", idx);
 792                 goto badidx;
 793         }
 794
 795         hf->echo_id = idx;
 796         hf->channel = dev->channel;
 797         hf->flags = 0;
 798         hf->reserved = 0;
 799
 800         if (can_is_canfd_skb(skb)) {
 801                 cfd = (struct canfd_frame *)skb->data;
 802
 803                 hf->can_id = cpu_to_le32(cfd->can_id);
 804                 hf->can_dlc = can_fd_len2dlc(cfd->len);
 805                 hf->flags |= GS_CAN_FLAG_FD;
 806                 if (cfd->flags & CANFD_BRS)
 807                         hf->flags |= GS_CAN_FLAG_BRS;
 808                 if (cfd->flags & CANFD_ESI)
 809                         hf->flags |= GS_CAN_FLAG_ESI;
 810
 811                 memcpy(hf->canfd->data, cfd->data, cfd->len);
 812         } else {
 813                 cf = (struct can_frame *)skb->data;
 814
 815                 hf->can_id = cpu_to_le32(cf->can_id);
 816                 hf->can_dlc = can_get_cc_dlc(cf, dev->can.ctrlmode);
 817
 818                 memcpy(hf->classic_can->data, cf->data, cf->len);
 819         }
 820
 821         usb_fill_bulk_urb(urb, dev->udev,
 822                           usb_sndbulkpipe(dev->udev, GS_USB_ENDPOINT_OUT),
 823                           hf, dev->hf_size_tx,
 824                           gs_usb_xmit_callback, txc);
 825
 826         urb->transfer_flags |= URB_FREE_BUFFER;
 827         usb_anchor_urb(urb, &dev->tx_submitted);
 828
 829         can_put_echo_skb(skb, netdev, idx, 0);
 830
 831         atomic_inc(&dev->active_tx_urbs);
 832
 833         rc = usb_submit_urb(urb, GFP_ATOMIC);
 834         if (unlikely(rc)) {                     /* usb send failed */
 835                 atomic_dec(&dev->active_tx_urbs);
 836
 837                 can_free_echo_skb(netdev, idx, NULL);
 838                 gs_free_tx_context(txc);
 839
 840                 usb_unanchor_urb(urb);
 841
 842                 if (rc == -ENODEV) {
 843                         netif_device_detach(netdev);
 844                 } else {
 845                         netdev_err(netdev, "usb_submit failed (err=%d)\n", rc);
 846                         stats->tx_dropped++;
 847                 }
 848         } else {
 849                 /* Slow down tx path */
 850                 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS)
 851                         netif_stop_queue(netdev);
 852         }
 853
 854         /* let usb core take care of this urb */
 855         usb_free_urb(urb);
 856
 857         return NETDEV_TX_OK;
 858
 859 badidx:
 860         kfree(hf);
 861 nomem_hf:
 862         usb_free_urb(urb);
 863
 864 nomem_urb:
 865         gs_free_tx_context(txc);
 866         dev_kfree_skb(skb);
 867         stats->tx_dropped++;
 868         return NETDEV_TX_OK;
 869 }
 870
 871 static int gs_can_open(struct net_device *netdev)
 872 {
 873         struct gs_can *dev = netdev_priv(netdev);
 874         struct gs_usb *parent = dev->parent;
 875         struct gs_device_mode dm = {
 876                 .mode = cpu_to_le32(GS_CAN_MODE_START),
 877         };
 878         struct gs_host_frame *hf;
 879         struct urb *urb = NULL;
 880         u32 ctrlmode;
 881         u32 flags = 0;
 882         int rc, i;
 883
 884         rc = open_candev(netdev);
 885         if (rc)
 886                 return rc;
 887
 888         ctrlmode = dev->can.ctrlmode;
 889         if (ctrlmode & CAN_CTRLMODE_FD) {
 890                 if (dev->feature & GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX)
 891                         dev->hf_size_tx = struct_size(hf, canfd_quirk, 1);
 892                 else
 893                         dev->hf_size_tx = struct_size(hf, canfd, 1);
 894         } else {
 895                 if (dev->feature & GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX)
 896                         dev->hf_size_tx = struct_size(hf, classic_can_quirk, 1);
 897                 else
 898                         dev->hf_size_tx = struct_size(hf, classic_can, 1);
 899         }
 900
 901         can_rx_offload_enable(&dev->offload);
 902
 903         if (!parent->active_channels) {
 904                 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
 905                         gs_usb_timestamp_init(parent);
 906
 907                 for (i = 0; i < GS_MAX_RX_URBS; i++) {
 908                         u8 *buf;
 909
 910                         /* alloc rx urb */
 911                         urb = usb_alloc_urb(0, GFP_KERNEL);
 912                         if (!urb) {
 913                                 rc = -ENOMEM;
 914                                 goto out_usb_kill_anchored_urbs;
 915                         }
 916
 917                         /* alloc rx buffer */
 918                         buf = kmalloc(dev->parent->hf_size_rx,
 919                                       GFP_KERNEL);
 920                         if (!buf) {
 921                                 rc = -ENOMEM;
 922                                 goto out_usb_free_urb;
 923                         }
 924
 925                         /* fill, anchor, and submit rx urb */
 926                         usb_fill_bulk_urb(urb,
 927                                           dev->udev,
 928                                           usb_rcvbulkpipe(dev->udev,
 929                                                           GS_USB_ENDPOINT_IN),
 930                                           buf,
 931                                           dev->parent->hf_size_rx,
 932                                           gs_usb_receive_bulk_callback, parent);
 933                         urb->transfer_flags |= URB_FREE_BUFFER;
 934
 935                         usb_anchor_urb(urb, &parent->rx_submitted);
 936
 937                         rc = usb_submit_urb(urb, GFP_KERNEL);
 938                         if (rc) {
 939                                 if (rc == -ENODEV)
 940                                         netif_device_detach(dev->netdev);
 941
 942                                 netdev_err(netdev,
 943                                            "usb_submit_urb() failed, error %pe\n",
 944                                            ERR_PTR(rc));
 945
 946                                 goto out_usb_unanchor_urb;
 947                         }
 948
 949                         /* Drop reference,
 950                          * USB core will take care of freeing it
 951                          */
 952                         usb_free_urb(urb);
 953                 }
 954         }
 955
 956         /* flags */
 957         if (ctrlmode & CAN_CTRLMODE_LOOPBACK)
 958                 flags |= GS_CAN_MODE_LOOP_BACK;
 959
 960         if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
 961                 flags |= GS_CAN_MODE_LISTEN_ONLY;
 962
 963         if (ctrlmode & CAN_CTRLMODE_3_SAMPLES)
 964                 flags |= GS_CAN_MODE_TRIPLE_SAMPLE;
 965
 966         if (ctrlmode & CAN_CTRLMODE_ONE_SHOT)
 967                 flags |= GS_CAN_MODE_ONE_SHOT;
 968
 969         if (ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
 970                 flags |= GS_CAN_MODE_BERR_REPORTING;
 971
 972         if (ctrlmode & CAN_CTRLMODE_FD)
 973                 flags |= GS_CAN_MODE_FD;
 974
 975         /* if hardware supports timestamps, enable it */
 976         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
 977                 flags |= GS_CAN_MODE_HW_TIMESTAMP;
 978
 979         /* finally start device */
 980         dev->can.state = CAN_STATE_ERROR_ACTIVE;
 981         dm.flags = cpu_to_le32(flags);
 982         rc = usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_MODE,
 983                                   USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
 984                                   dev->channel, 0, &dm, sizeof(dm), 1000,
 985                                   GFP_KERNEL);
 986         if (rc) {
 987                 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc);
 988                 dev->can.state = CAN_STATE_STOPPED;
 989
 990                 goto out_usb_kill_anchored_urbs;
 991         }
 992
 993         parent->active_channels++;
 994         if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY))
 995                 netif_start_queue(netdev);
 996
 997         return 0;
 998
 999 out_usb_unanchor_urb:
1000         usb_unanchor_urb(urb);
1001 out_usb_free_urb:
1002         usb_free_urb(urb);
1003 out_usb_kill_anchored_urbs:
1004         if (!parent->active_channels) {
1005                 usb_kill_anchored_urbs(&dev->tx_submitted);
1006
1007                 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1008                         gs_usb_timestamp_stop(parent);
1009         }
1010
1011         can_rx_offload_disable(&dev->offload);
1012         close_candev(netdev);
1013
1014         return rc;
1015 }
1016
1017 static int gs_usb_get_state(const struct net_device *netdev,
1018                             struct can_berr_counter *bec,
1019                             enum can_state *state)
1020 {
1021         struct gs_can *dev = netdev_priv(netdev);
1022         struct gs_device_state ds;
1023         int rc;
1024
1025         rc = usb_control_msg_recv(dev->udev, 0, GS_USB_BREQ_GET_STATE,
1026                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1027                                   dev->channel, 0,
1028                                   &ds, sizeof(ds),
1029                                   USB_CTRL_GET_TIMEOUT,
1030                                   GFP_KERNEL);
1031         if (rc)
1032                 return rc;
1033
1034         if (le32_to_cpu(ds.state) >= CAN_STATE_MAX)
1035                 return -EOPNOTSUPP;
1036
1037         *state = le32_to_cpu(ds.state);
1038         bec->txerr = le32_to_cpu(ds.txerr);
1039         bec->rxerr = le32_to_cpu(ds.rxerr);
1040
1041         return 0;
1042 }
1043
1044 static int gs_usb_can_get_berr_counter(const struct net_device *netdev,
1045                                        struct can_berr_counter *bec)
1046 {
1047         enum can_state state;
1048
1049         return gs_usb_get_state(netdev, bec, &state);
1050 }
1051
1052 static int gs_can_close(struct net_device *netdev)
1053 {
1054         int rc;
1055         struct gs_can *dev = netdev_priv(netdev);
1056         struct gs_usb *parent = dev->parent;
1057
1058         netif_stop_queue(netdev);
1059
1060         /* Stop polling */
1061         parent->active_channels--;
1062         if (!parent->active_channels) {
1063                 usb_kill_anchored_urbs(&parent->rx_submitted);
1064
1065                 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1066                         gs_usb_timestamp_stop(parent);
1067         }
1068
1069         /* Stop sending URBs */
1070         usb_kill_anchored_urbs(&dev->tx_submitted);
1071         atomic_set(&dev->active_tx_urbs, 0);
1072
1073         dev->can.state = CAN_STATE_STOPPED;
1074
1075         /* reset the device */
1076         gs_cmd_reset(dev);
1077
1078         /* reset tx contexts */
1079         for (rc = 0; rc < GS_MAX_TX_URBS; rc++) {
1080                 dev->tx_context[rc].dev = dev;
1081                 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS;
1082         }
1083
1084         can_rx_offload_disable(&dev->offload);
1085
1086         /* close the netdev */
1087         close_candev(netdev);
1088
1089         return 0;
1090 }
1091
1092 static int gs_can_eth_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1093 {
1094         const struct gs_can *dev = netdev_priv(netdev);
1095
1096         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1097                 return can_eth_ioctl_hwts(netdev, ifr, cmd);
1098
1099         return -EOPNOTSUPP;
1100 }
1101
1102 static const struct net_device_ops gs_usb_netdev_ops = {
1103         .ndo_open = gs_can_open,
1104         .ndo_stop = gs_can_close,
1105         .ndo_start_xmit = gs_can_start_xmit,
1106         .ndo_change_mtu = can_change_mtu,
1107         .ndo_eth_ioctl = gs_can_eth_ioctl,
1108 };
1109
1110 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify)
1111 {
1112         struct gs_can *dev = netdev_priv(netdev);
1113         struct gs_identify_mode imode;
1114
1115         if (do_identify)
1116                 imode.mode = cpu_to_le32(GS_CAN_IDENTIFY_ON);
1117         else
1118                 imode.mode = cpu_to_le32(GS_CAN_IDENTIFY_OFF);
1119
1120         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_IDENTIFY,
1121                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1122                                     dev->channel, 0, &imode, sizeof(imode), 100,
1123                                     GFP_KERNEL);
1124 }
1125
1126 /* blink LED's for finding the this interface */
1127 static int gs_usb_set_phys_id(struct net_device *netdev,
1128                               enum ethtool_phys_id_state state)
1129 {
1130         const struct gs_can *dev = netdev_priv(netdev);
1131         int rc = 0;
1132
1133         if (!(dev->feature & GS_CAN_FEATURE_IDENTIFY))
1134                 return -EOPNOTSUPP;
1135
1136         switch (state) {
1137         case ETHTOOL_ID_ACTIVE:
1138                 rc = gs_usb_set_identify(netdev, GS_CAN_IDENTIFY_ON);
1139                 break;
1140         case ETHTOOL_ID_INACTIVE:
1141                 rc = gs_usb_set_identify(netdev, GS_CAN_IDENTIFY_OFF);
1142                 break;
1143         default:
1144                 break;
1145         }
1146
1147         return rc;
1148 }
1149
1150 static int gs_usb_get_ts_info(struct net_device *netdev,
1151                               struct kernel_ethtool_ts_info *info)
1152 {
1153         struct gs_can *dev = netdev_priv(netdev);
1154
1155         /* report if device supports HW timestamps */
1156         if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1157                 return can_ethtool_op_get_ts_info_hwts(netdev, info);
1158
1159         return ethtool_op_get_ts_info(netdev, info);
1160 }
1161
1162 static const struct ethtool_ops gs_usb_ethtool_ops = {
1163         .set_phys_id = gs_usb_set_phys_id,
1164         .get_ts_info = gs_usb_get_ts_info,
1165 };
1166
1167 static int gs_usb_get_termination(struct net_device *netdev, u16 *term)
1168 {
1169         struct gs_can *dev = netdev_priv(netdev);
1170         struct gs_device_termination_state term_state;
1171         int rc;
1172
1173         rc = usb_control_msg_recv(dev->udev, 0, GS_USB_BREQ_GET_TERMINATION,
1174                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1175                                   dev->channel, 0,
1176                                   &term_state, sizeof(term_state), 1000,
1177                                   GFP_KERNEL);
1178         if (rc)
1179                 return rc;
1180
1181         if (term_state.state == cpu_to_le32(GS_CAN_TERMINATION_STATE_ON))
1182                 *term = GS_USB_TERMINATION_ENABLED;
1183         else
1184                 *term = GS_USB_TERMINATION_DISABLED;
1185
1186         return 0;
1187 }
1188
1189 static int gs_usb_set_termination(struct net_device *netdev, u16 term)
1190 {
1191         struct gs_can *dev = netdev_priv(netdev);
1192         struct gs_device_termination_state term_state;
1193
1194         if (term == GS_USB_TERMINATION_ENABLED)
1195                 term_state.state = cpu_to_le32(GS_CAN_TERMINATION_STATE_ON);
1196         else
1197                 term_state.state = cpu_to_le32(GS_CAN_TERMINATION_STATE_OFF);
1198
1199         return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_SET_TERMINATION,
1200                                     USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1201                                     dev->channel, 0,
1202                                     &term_state, sizeof(term_state), 1000,
1203                                     GFP_KERNEL);
1204 }
1205
1206 static const u16 gs_usb_termination_const[] = {
1207         GS_USB_TERMINATION_DISABLED,
1208         GS_USB_TERMINATION_ENABLED
1209 };
1210
1211 static struct gs_can *gs_make_candev(unsigned int channel,
1212                                      struct usb_interface *intf,
1213                                      struct gs_device_config *dconf)
1214 {
1215         struct gs_can *dev;
1216         struct net_device *netdev;
1217         int rc;
1218         struct gs_device_bt_const_extended bt_const_extended;
1219         struct gs_device_bt_const bt_const;
1220         u32 feature;
1221
1222         /* fetch bit timing constants */
1223         rc = usb_control_msg_recv(interface_to_usbdev(intf), 0,
1224                                   GS_USB_BREQ_BT_CONST,
1225                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1226                                   channel, 0, &bt_const, sizeof(bt_const), 1000,
1227                                   GFP_KERNEL);
1228
1229         if (rc) {
1230                 dev_err(&intf->dev,
1231                         "Couldn't get bit timing const for channel %d (%pe)\n",
1232                         channel, ERR_PTR(rc));
1233                 return ERR_PTR(rc);
1234         }
1235
1236         /* create netdev */
1237         netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS);
1238         if (!netdev) {
1239                 dev_err(&intf->dev, "Couldn't allocate candev\n");
1240                 return ERR_PTR(-ENOMEM);
1241         }
1242
1243         dev = netdev_priv(netdev);
1244
1245         netdev->netdev_ops = &gs_usb_netdev_ops;
1246         netdev->ethtool_ops = &gs_usb_ethtool_ops;
1247
1248         netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */
1249         netdev->dev_id = channel;
1250
1251         /* dev setup */
1252         strcpy(dev->bt_const.name, KBUILD_MODNAME);
1253         dev->bt_const.tseg1_min = le32_to_cpu(bt_const.tseg1_min);
1254         dev->bt_const.tseg1_max = le32_to_cpu(bt_const.tseg1_max);
1255         dev->bt_const.tseg2_min = le32_to_cpu(bt_const.tseg2_min);
1256         dev->bt_const.tseg2_max = le32_to_cpu(bt_const.tseg2_max);
1257         dev->bt_const.sjw_max = le32_to_cpu(bt_const.sjw_max);
1258         dev->bt_const.brp_min = le32_to_cpu(bt_const.brp_min);
1259         dev->bt_const.brp_max = le32_to_cpu(bt_const.brp_max);
1260         dev->bt_const.brp_inc = le32_to_cpu(bt_const.brp_inc);
1261
1262         dev->udev = interface_to_usbdev(intf);
1263         dev->netdev = netdev;
1264         dev->channel = channel;
1265
1266         init_usb_anchor(&dev->tx_submitted);
1267         atomic_set(&dev->active_tx_urbs, 0);
1268         spin_lock_init(&dev->tx_ctx_lock);
1269         for (rc = 0; rc < GS_MAX_TX_URBS; rc++) {
1270                 dev->tx_context[rc].dev = dev;
1271                 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS;
1272         }
1273
1274         /* can setup */
1275         dev->can.state = CAN_STATE_STOPPED;
1276         dev->can.clock.freq = le32_to_cpu(bt_const.fclk_can);
1277         dev->can.bittiming_const = &dev->bt_const;
1278         dev->can.do_set_bittiming = gs_usb_set_bittiming;
1279
1280         dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC;
1281
1282         feature = le32_to_cpu(bt_const.feature);
1283         dev->feature = FIELD_GET(GS_CAN_FEATURE_MASK, feature);
1284         if (feature & GS_CAN_FEATURE_LISTEN_ONLY)
1285                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY;
1286
1287         if (feature & GS_CAN_FEATURE_LOOP_BACK)
1288                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK;
1289
1290         if (feature & GS_CAN_FEATURE_TRIPLE_SAMPLE)
1291                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1292
1293         if (feature & GS_CAN_FEATURE_ONE_SHOT)
1294                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
1295
1296         if (feature & GS_CAN_FEATURE_FD) {
1297                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_FD;
1298                 /* The data bit timing will be overwritten, if
1299                  * GS_CAN_FEATURE_BT_CONST_EXT is set.
1300                  */
1301                 dev->can.data_bittiming_const = &dev->bt_const;
1302                 dev->can.do_set_data_bittiming = gs_usb_set_data_bittiming;
1303         }
1304
1305         if (feature & GS_CAN_FEATURE_TERMINATION) {
1306                 rc = gs_usb_get_termination(netdev, &dev->can.termination);
1307                 if (rc) {
1308                         dev->feature &= ~GS_CAN_FEATURE_TERMINATION;
1309
1310                         dev_info(&intf->dev,
1311                                  "Disabling termination support for channel %d (%pe)\n",
1312                                  channel, ERR_PTR(rc));
1313                 } else {
1314                         dev->can.termination_const = gs_usb_termination_const;
1315                         dev->can.termination_const_cnt = ARRAY_SIZE(gs_usb_termination_const);
1316                         dev->can.do_set_termination = gs_usb_set_termination;
1317                 }
1318         }
1319
1320         if (feature & GS_CAN_FEATURE_BERR_REPORTING)
1321                 dev->can.ctrlmode_supported |= CAN_CTRLMODE_BERR_REPORTING;
1322
1323         if (feature & GS_CAN_FEATURE_GET_STATE)
1324                 dev->can.do_get_berr_counter = gs_usb_can_get_berr_counter;
1325
1326         /* The CANtact Pro from LinkLayer Labs is based on the
1327          * LPC54616 µC, which is affected by the NXP LPC USB transfer
1328          * erratum. However, the current firmware (version 2) doesn't
1329          * set the GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX bit. Set the
1330          * feature GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX to workaround
1331          * this issue.
1332          *
1333          * For the GS_USB_BREQ_DATA_BITTIMING USB control message the
1334          * CANtact Pro firmware uses a request value, which is already
1335          * used by the candleLight firmware for a different purpose
1336          * (GS_USB_BREQ_GET_USER_ID). Set the feature
1337          * GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO to workaround this
1338          * issue.
1339          */
1340         if (dev->udev->descriptor.idVendor == cpu_to_le16(USB_GS_USB_1_VENDOR_ID) &&
1341             dev->udev->descriptor.idProduct == cpu_to_le16(USB_GS_USB_1_PRODUCT_ID) &&
1342             dev->udev->manufacturer && dev->udev->product &&
1343             !strcmp(dev->udev->manufacturer, "LinkLayer Labs") &&
1344             !strcmp(dev->udev->product, "CANtact Pro") &&
1345             (le32_to_cpu(dconf->sw_version) <= 2))
1346                 dev->feature |= GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX |
1347                         GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO;
1348
1349         /* GS_CAN_FEATURE_IDENTIFY is only supported for sw_version > 1 */
1350         if (!(le32_to_cpu(dconf->sw_version) > 1 &&
1351               feature & GS_CAN_FEATURE_IDENTIFY))
1352                 dev->feature &= ~GS_CAN_FEATURE_IDENTIFY;
1353
1354         /* fetch extended bit timing constants if device has feature
1355          * GS_CAN_FEATURE_FD and GS_CAN_FEATURE_BT_CONST_EXT
1356          */
1357         if (feature & GS_CAN_FEATURE_FD &&
1358             feature & GS_CAN_FEATURE_BT_CONST_EXT) {
1359                 rc = usb_control_msg_recv(interface_to_usbdev(intf), 0,
1360                                           GS_USB_BREQ_BT_CONST_EXT,
1361                                           USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1362                                           channel, 0, &bt_const_extended,
1363                                           sizeof(bt_const_extended),
1364                                           1000, GFP_KERNEL);
1365                 if (rc) {
1366                         dev_err(&intf->dev,
1367                                 "Couldn't get extended bit timing const for channel %d (%pe)\n",
1368                                 channel, ERR_PTR(rc));
1369                         goto out_free_candev;
1370                 }
1371
1372                 strcpy(dev->data_bt_const.name, KBUILD_MODNAME);
1373                 dev->data_bt_const.tseg1_min = le32_to_cpu(bt_const_extended.dtseg1_min);
1374                 dev->data_bt_const.tseg1_max = le32_to_cpu(bt_const_extended.dtseg1_max);
1375                 dev->data_bt_const.tseg2_min = le32_to_cpu(bt_const_extended.dtseg2_min);
1376                 dev->data_bt_const.tseg2_max = le32_to_cpu(bt_const_extended.dtseg2_max);
1377                 dev->data_bt_const.sjw_max = le32_to_cpu(bt_const_extended.dsjw_max);
1378                 dev->data_bt_const.brp_min = le32_to_cpu(bt_const_extended.dbrp_min);
1379                 dev->data_bt_const.brp_max = le32_to_cpu(bt_const_extended.dbrp_max);
1380                 dev->data_bt_const.brp_inc = le32_to_cpu(bt_const_extended.dbrp_inc);
1381
1382                 dev->can.data_bittiming_const = &dev->data_bt_const;
1383         }
1384
1385         can_rx_offload_add_manual(netdev, &dev->offload, GS_NAPI_WEIGHT);
1386         SET_NETDEV_DEV(netdev, &intf->dev);
1387
1388         rc = register_candev(dev->netdev);
1389         if (rc) {
1390                 dev_err(&intf->dev,
1391                         "Couldn't register candev for channel %d (%pe)\n",
1392                         channel, ERR_PTR(rc));
1393                 goto out_can_rx_offload_del;
1394         }
1395
1396         return dev;
1397
1398 out_can_rx_offload_del:
1399         can_rx_offload_del(&dev->offload);
1400 out_free_candev:
1401         free_candev(dev->netdev);
1402         return ERR_PTR(rc);
1403 }
1404
1405 static void gs_destroy_candev(struct gs_can *dev)
1406 {
1407         unregister_candev(dev->netdev);
1408         can_rx_offload_del(&dev->offload);
1409         free_candev(dev->netdev);
1410 }
1411
1412 static int gs_usb_probe(struct usb_interface *intf,
1413                         const struct usb_device_id *id)
1414 {
1415         struct usb_device *udev = interface_to_usbdev(intf);
1416         struct gs_host_frame *hf;
1417         struct gs_usb *parent;
1418         struct gs_host_config hconf = {
1419                 .byte_order = cpu_to_le32(0x0000beef),
1420         };
1421         struct gs_device_config dconf;
1422         unsigned int icount, i;
1423         int rc;
1424
1425         /* send host config */
1426         rc = usb_control_msg_send(udev, 0,
1427                                   GS_USB_BREQ_HOST_FORMAT,
1428                                   USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1429                                   1, intf->cur_altsetting->desc.bInterfaceNumber,
1430                                   &hconf, sizeof(hconf), 1000,
1431                                   GFP_KERNEL);
1432         if (rc) {
1433                 dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", rc);
1434                 return rc;
1435         }
1436
1437         /* read device config */
1438         rc = usb_control_msg_recv(udev, 0,
1439                                   GS_USB_BREQ_DEVICE_CONFIG,
1440                                   USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1441                                   1, intf->cur_altsetting->desc.bInterfaceNumber,
1442                                   &dconf, sizeof(dconf), 1000,
1443                                   GFP_KERNEL);
1444         if (rc) {
1445                 dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n",
1446                         rc);
1447                 return rc;
1448         }
1449
1450         icount = dconf.icount + 1;
1451         dev_info(&intf->dev, "Configuring for %u interfaces\n", icount);
1452
1453         if (icount > GS_MAX_INTF) {
1454                 dev_err(&intf->dev,
1455                         "Driver cannot handle more that %u CAN interfaces\n",
1456                         GS_MAX_INTF);
1457                 return -EINVAL;
1458         }
1459
1460         parent = kzalloc(sizeof(*parent), GFP_KERNEL);
1461         if (!parent)
1462                 return -ENOMEM;
1463
1464         init_usb_anchor(&parent->rx_submitted);
1465
1466         usb_set_intfdata(intf, parent);
1467         parent->udev = udev;
1468
1469         for (i = 0; i < icount; i++) {
1470                 unsigned int hf_size_rx = 0;
1471
1472                 parent->canch[i] = gs_make_candev(i, intf, &dconf);
1473                 if (IS_ERR_OR_NULL(parent->canch[i])) {
1474                         /* save error code to return later */
1475                         rc = PTR_ERR(parent->canch[i]);
1476
1477                         /* on failure destroy previously created candevs */
1478                         icount = i;
1479                         for (i = 0; i < icount; i++)
1480                                 gs_destroy_candev(parent->canch[i]);
1481
1482                         usb_kill_anchored_urbs(&parent->rx_submitted);
1483                         kfree(parent);
1484                         return rc;
1485                 }
1486                 parent->canch[i]->parent = parent;
1487
1488                 /* set RX packet size based on FD and if hardware
1489                  * timestamps are supported.
1490                  */
1491                 if (parent->canch[i]->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
1492                         if (parent->canch[i]->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1493                                 hf_size_rx = struct_size(hf, canfd_ts, 1);
1494                         else
1495                                 hf_size_rx = struct_size(hf, canfd, 1);
1496                 } else {
1497                         if (parent->canch[i]->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1498                                 hf_size_rx = struct_size(hf, classic_can_ts, 1);
1499                         else
1500                                 hf_size_rx = struct_size(hf, classic_can, 1);
1501                 }
1502                 parent->hf_size_rx = max(parent->hf_size_rx, hf_size_rx);
1503         }
1504
1505         return 0;
1506 }
1507
1508 static void gs_usb_disconnect(struct usb_interface *intf)
1509 {
1510         struct gs_usb *parent = usb_get_intfdata(intf);
1511         unsigned int i;
1512
1513         usb_set_intfdata(intf, NULL);
1514
1515         if (!parent) {
1516                 dev_err(&intf->dev, "Disconnect (nodata)\n");
1517                 return;
1518         }
1519
1520         for (i = 0; i < GS_MAX_INTF; i++)
1521                 if (parent->canch[i])
1522                         gs_destroy_candev(parent->canch[i]);
1523
1524         kfree(parent);
1525 }
1526
1527 static const struct usb_device_id gs_usb_table[] = {
1528         { USB_DEVICE_INTERFACE_NUMBER(USB_GS_USB_1_VENDOR_ID,
1529                                       USB_GS_USB_1_PRODUCT_ID, 0) },
1530         { USB_DEVICE_INTERFACE_NUMBER(USB_CANDLELIGHT_VENDOR_ID,
1531                                       USB_CANDLELIGHT_PRODUCT_ID, 0) },
1532         { USB_DEVICE_INTERFACE_NUMBER(USB_CES_CANEXT_FD_VENDOR_ID,
1533                                       USB_CES_CANEXT_FD_PRODUCT_ID, 0) },
1534         { USB_DEVICE_INTERFACE_NUMBER(USB_ABE_CANDEBUGGER_FD_VENDOR_ID,
1535                                       USB_ABE_CANDEBUGGER_FD_PRODUCT_ID, 0) },
1536         { USB_DEVICE_INTERFACE_NUMBER(USB_XYLANTA_SAINT3_VENDOR_ID,
1537                                       USB_XYLANTA_SAINT3_PRODUCT_ID, 0) },
1538         {} /* Terminating entry */
1539 };
1540
1541 MODULE_DEVICE_TABLE(usb, gs_usb_table);
1542
1543 static struct usb_driver gs_usb_driver = {
1544         .name = KBUILD_MODNAME,
1545         .probe = gs_usb_probe,
1546         .disconnect = gs_usb_disconnect,
1547         .id_table = gs_usb_table,
1548 };
1549
1550 module_usb_driver(gs_usb_driver);
1551
1552 MODULE_AUTHOR("Maximilian Schneider <[email protected]>");
1553 MODULE_DESCRIPTION(
1554 "Socket CAN device driver for Geschwister Schneider Technologie-, "
1555 "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces\n"
1556 "and bytewerk.org candleLight USB CAN interfaces.");
1557 MODULE_LICENSE("GPL v2");