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/ethtool.h> 13 #include <linux/init.h> 14 #include <linux/signal.h> 15 #include <linux/module.h> 16 #include <linux/netdevice.h> 17 #include <linux/usb.h> 18 19 #include <linux/can.h> 20 #include <linux/can/dev.h> 21 #include <linux/can/error.h> 22 23 /* Device specific constants */ 24 #define USB_GSUSB_1_VENDOR_ID 0x1d50 25 #define USB_GSUSB_1_PRODUCT_ID 0x606f 26 27 #define USB_CANDLELIGHT_VENDOR_ID 0x1209 28 #define USB_CANDLELIGHT_PRODUCT_ID 0x2323 29 30 #define GSUSB_ENDPOINT_IN 1 31 #define GSUSB_ENDPOINT_OUT 2 32 33 /* Device specific constants */ 34 enum gs_usb_breq { 35 GS_USB_BREQ_HOST_FORMAT = 0, 36 GS_USB_BREQ_BITTIMING, 37 GS_USB_BREQ_MODE, 38 GS_USB_BREQ_BERR, 39 GS_USB_BREQ_BT_CONST, 40 GS_USB_BREQ_DEVICE_CONFIG, 41 GS_USB_BREQ_TIMESTAMP, 42 GS_USB_BREQ_IDENTIFY, 43 }; 44 45 enum gs_can_mode { 46 /* reset a channel. turns it off */ 47 GS_CAN_MODE_RESET = 0, 48 /* starts a channel */ 49 GS_CAN_MODE_START 50 }; 51 52 enum gs_can_state { 53 GS_CAN_STATE_ERROR_ACTIVE = 0, 54 GS_CAN_STATE_ERROR_WARNING, 55 GS_CAN_STATE_ERROR_PASSIVE, 56 GS_CAN_STATE_BUS_OFF, 57 GS_CAN_STATE_STOPPED, 58 GS_CAN_STATE_SLEEPING 59 }; 60 61 enum gs_can_identify_mode { 62 GS_CAN_IDENTIFY_OFF = 0, 63 GS_CAN_IDENTIFY_ON 64 }; 65 66 /* data types passed between host and device */ 67 68 /* The firmware on the original USB2CAN by Geschwister Schneider 69 * Technologie Entwicklungs- und Vertriebs UG exchanges all data 70 * between the host and the device in host byte order. This is done 71 * with the struct gs_host_config::byte_order member, which is sent 72 * first to indicate the desired byte order. 73 * 74 * The widely used open source firmware candleLight doesn't support 75 * this feature and exchanges the data in little endian byte order. 76 */ 77 struct gs_host_config { 78 __le32 byte_order; 79 } __packed; 80 81 struct gs_device_config { 82 u8 reserved1; 83 u8 reserved2; 84 u8 reserved3; 85 u8 icount; 86 __le32 sw_version; 87 __le32 hw_version; 88 } __packed; 89 90 #define GS_CAN_MODE_NORMAL 0 91 #define GS_CAN_MODE_LISTEN_ONLY BIT(0) 92 #define GS_CAN_MODE_LOOP_BACK BIT(1) 93 #define GS_CAN_MODE_TRIPLE_SAMPLE BIT(2) 94 #define GS_CAN_MODE_ONE_SHOT BIT(3) 95 96 struct gs_device_mode { 97 __le32 mode; 98 __le32 flags; 99 } __packed; 100 101 struct gs_device_state { 102 __le32 state; 103 __le32 rxerr; 104 __le32 txerr; 105 } __packed; 106 107 struct gs_device_bittiming { 108 __le32 prop_seg; 109 __le32 phase_seg1; 110 __le32 phase_seg2; 111 __le32 sjw; 112 __le32 brp; 113 } __packed; 114 115 struct gs_identify_mode { 116 __le32 mode; 117 } __packed; 118 119 #define GS_CAN_FEATURE_LISTEN_ONLY BIT(0) 120 #define GS_CAN_FEATURE_LOOP_BACK BIT(1) 121 #define GS_CAN_FEATURE_TRIPLE_SAMPLE BIT(2) 122 #define GS_CAN_FEATURE_ONE_SHOT BIT(3) 123 #define GS_CAN_FEATURE_HW_TIMESTAMP BIT(4) 124 #define GS_CAN_FEATURE_IDENTIFY BIT(5) 125 126 struct gs_device_bt_const { 127 __le32 feature; 128 __le32 fclk_can; 129 __le32 tseg1_min; 130 __le32 tseg1_max; 131 __le32 tseg2_min; 132 __le32 tseg2_max; 133 __le32 sjw_max; 134 __le32 brp_min; 135 __le32 brp_max; 136 __le32 brp_inc; 137 } __packed; 138 139 #define GS_CAN_FLAG_OVERFLOW 1 140 141 struct gs_host_frame { 142 u32 echo_id; 143 __le32 can_id; 144 145 u8 can_dlc; 146 u8 channel; 147 u8 flags; 148 u8 reserved; 149 150 u8 data[8]; 151 } __packed; 152 /* The GS USB devices make use of the same flags and masks as in 153 * linux/can.h and linux/can/error.h, and no additional mapping is necessary. 154 */ 155 156 /* Only send a max of GS_MAX_TX_URBS frames per channel at a time. */ 157 #define GS_MAX_TX_URBS 10 158 /* Only launch a max of GS_MAX_RX_URBS usb requests at a time. */ 159 #define GS_MAX_RX_URBS 30 160 /* Maximum number of interfaces the driver supports per device. 161 * Current hardware only supports 2 interfaces. The future may vary. 162 */ 163 #define GS_MAX_INTF 2 164 165 struct gs_tx_context { 166 struct gs_can *dev; 167 unsigned int echo_id; 168 }; 169 170 struct gs_can { 171 struct can_priv can; /* must be the first member */ 172 173 struct gs_usb *parent; 174 175 struct net_device *netdev; 176 struct usb_device *udev; 177 struct usb_interface *iface; 178 179 struct can_bittiming_const bt_const; 180 unsigned int channel; /* channel number */ 181 182 /* This lock prevents a race condition between xmit and receive. */ 183 spinlock_t tx_ctx_lock; 184 struct gs_tx_context tx_context[GS_MAX_TX_URBS]; 185 186 struct usb_anchor tx_submitted; 187 atomic_t active_tx_urbs; 188 }; 189 190 /* usb interface struct */ 191 struct gs_usb { 192 struct gs_can *canch[GS_MAX_INTF]; 193 struct usb_anchor rx_submitted; 194 atomic_t active_channels; 195 struct usb_device *udev; 196 }; 197 198 /* 'allocate' a tx context. 199 * returns a valid tx context or NULL if there is no space. 200 */ 201 static struct gs_tx_context *gs_alloc_tx_context(struct gs_can *dev) 202 { 203 int i = 0; 204 unsigned long flags; 205 206 spin_lock_irqsave(&dev->tx_ctx_lock, flags); 207 208 for (; i < GS_MAX_TX_URBS; i++) { 209 if (dev->tx_context[i].echo_id == GS_MAX_TX_URBS) { 210 dev->tx_context[i].echo_id = i; 211 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 212 return &dev->tx_context[i]; 213 } 214 } 215 216 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 217 return NULL; 218 } 219 220 /* releases a tx context 221 */ 222 static void gs_free_tx_context(struct gs_tx_context *txc) 223 { 224 txc->echo_id = GS_MAX_TX_URBS; 225 } 226 227 /* Get a tx context by id. 228 */ 229 static struct gs_tx_context *gs_get_tx_context(struct gs_can *dev, 230 unsigned int id) 231 { 232 unsigned long flags; 233 234 if (id < GS_MAX_TX_URBS) { 235 spin_lock_irqsave(&dev->tx_ctx_lock, flags); 236 if (dev->tx_context[id].echo_id == id) { 237 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 238 return &dev->tx_context[id]; 239 } 240 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 241 } 242 return NULL; 243 } 244 245 static int gs_cmd_reset(struct gs_can *gsdev) 246 { 247 struct gs_device_mode *dm; 248 struct usb_interface *intf = gsdev->iface; 249 int rc; 250 251 dm = kzalloc(sizeof(*dm), GFP_KERNEL); 252 if (!dm) 253 return -ENOMEM; 254 255 dm->mode = GS_CAN_MODE_RESET; 256 257 rc = usb_control_msg(interface_to_usbdev(intf), 258 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 259 GS_USB_BREQ_MODE, 260 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 261 gsdev->channel, 262 0, 263 dm, 264 sizeof(*dm), 265 1000); 266 267 kfree(dm); 268 269 return rc; 270 } 271 272 static void gs_update_state(struct gs_can *dev, struct can_frame *cf) 273 { 274 struct can_device_stats *can_stats = &dev->can.can_stats; 275 276 if (cf->can_id & CAN_ERR_RESTARTED) { 277 dev->can.state = CAN_STATE_ERROR_ACTIVE; 278 can_stats->restarts++; 279 } else if (cf->can_id & CAN_ERR_BUSOFF) { 280 dev->can.state = CAN_STATE_BUS_OFF; 281 can_stats->bus_off++; 282 } else if (cf->can_id & CAN_ERR_CRTL) { 283 if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) || 284 (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) { 285 dev->can.state = CAN_STATE_ERROR_WARNING; 286 can_stats->error_warning++; 287 } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) || 288 (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) { 289 dev->can.state = CAN_STATE_ERROR_PASSIVE; 290 can_stats->error_passive++; 291 } else { 292 dev->can.state = CAN_STATE_ERROR_ACTIVE; 293 } 294 } 295 } 296 297 static void gs_usb_receive_bulk_callback(struct urb *urb) 298 { 299 struct gs_usb *usbcan = urb->context; 300 struct gs_can *dev; 301 struct net_device *netdev; 302 int rc; 303 struct net_device_stats *stats; 304 struct gs_host_frame *hf = urb->transfer_buffer; 305 struct gs_tx_context *txc; 306 struct can_frame *cf; 307 struct sk_buff *skb; 308 309 BUG_ON(!usbcan); 310 311 switch (urb->status) { 312 case 0: /* success */ 313 break; 314 case -ENOENT: 315 case -ESHUTDOWN: 316 return; 317 default: 318 /* do not resubmit aborted urbs. eg: when device goes down */ 319 return; 320 } 321 322 /* device reports out of range channel id */ 323 if (hf->channel >= GS_MAX_INTF) 324 goto resubmit_urb; 325 326 dev = usbcan->canch[hf->channel]; 327 328 netdev = dev->netdev; 329 stats = &netdev->stats; 330 331 if (!netif_device_present(netdev)) 332 return; 333 334 if (hf->echo_id == -1) { /* normal rx */ 335 skb = alloc_can_skb(dev->netdev, &cf); 336 if (!skb) 337 return; 338 339 cf->can_id = le32_to_cpu(hf->can_id); 340 341 can_frame_set_cc_len(cf, hf->can_dlc, dev->can.ctrlmode); 342 memcpy(cf->data, hf->data, 8); 343 344 /* ERROR frames tell us information about the controller */ 345 if (le32_to_cpu(hf->can_id) & CAN_ERR_FLAG) 346 gs_update_state(dev, cf); 347 348 netdev->stats.rx_packets++; 349 netdev->stats.rx_bytes += hf->can_dlc; 350 351 netif_rx(skb); 352 } else { /* echo_id == hf->echo_id */ 353 if (hf->echo_id >= GS_MAX_TX_URBS) { 354 netdev_err(netdev, 355 "Unexpected out of range echo id %u\n", 356 hf->echo_id); 357 goto resubmit_urb; 358 } 359 360 txc = gs_get_tx_context(dev, hf->echo_id); 361 362 /* bad devices send bad echo_ids. */ 363 if (!txc) { 364 netdev_err(netdev, 365 "Unexpected unused echo id %u\n", 366 hf->echo_id); 367 goto resubmit_urb; 368 } 369 370 netdev->stats.tx_packets++; 371 netdev->stats.tx_bytes += can_get_echo_skb(netdev, hf->echo_id, 372 NULL); 373 374 gs_free_tx_context(txc); 375 376 atomic_dec(&dev->active_tx_urbs); 377 378 netif_wake_queue(netdev); 379 } 380 381 if (hf->flags & GS_CAN_FLAG_OVERFLOW) { 382 skb = alloc_can_err_skb(netdev, &cf); 383 if (!skb) 384 goto resubmit_urb; 385 386 cf->can_id |= CAN_ERR_CRTL; 387 cf->len = CAN_ERR_DLC; 388 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 389 stats->rx_over_errors++; 390 stats->rx_errors++; 391 netif_rx(skb); 392 } 393 394 resubmit_urb: 395 usb_fill_bulk_urb(urb, 396 usbcan->udev, 397 usb_rcvbulkpipe(usbcan->udev, GSUSB_ENDPOINT_IN), 398 hf, 399 sizeof(struct gs_host_frame), 400 gs_usb_receive_bulk_callback, 401 usbcan 402 ); 403 404 rc = usb_submit_urb(urb, GFP_ATOMIC); 405 406 /* USB failure take down all interfaces */ 407 if (rc == -ENODEV) { 408 for (rc = 0; rc < GS_MAX_INTF; rc++) { 409 if (usbcan->canch[rc]) 410 netif_device_detach(usbcan->canch[rc]->netdev); 411 } 412 } 413 } 414 415 static int gs_usb_set_bittiming(struct net_device *netdev) 416 { 417 struct gs_can *dev = netdev_priv(netdev); 418 struct can_bittiming *bt = &dev->can.bittiming; 419 struct usb_interface *intf = dev->iface; 420 int rc; 421 struct gs_device_bittiming *dbt; 422 423 dbt = kmalloc(sizeof(*dbt), GFP_KERNEL); 424 if (!dbt) 425 return -ENOMEM; 426 427 dbt->prop_seg = cpu_to_le32(bt->prop_seg); 428 dbt->phase_seg1 = cpu_to_le32(bt->phase_seg1); 429 dbt->phase_seg2 = cpu_to_le32(bt->phase_seg2); 430 dbt->sjw = cpu_to_le32(bt->sjw); 431 dbt->brp = cpu_to_le32(bt->brp); 432 433 /* request bit timings */ 434 rc = usb_control_msg(interface_to_usbdev(intf), 435 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 436 GS_USB_BREQ_BITTIMING, 437 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 438 dev->channel, 439 0, 440 dbt, 441 sizeof(*dbt), 442 1000); 443 444 kfree(dbt); 445 446 if (rc < 0) 447 dev_err(netdev->dev.parent, "Couldn't set bittimings (err=%d)", 448 rc); 449 450 return (rc > 0) ? 0 : rc; 451 } 452 453 static void gs_usb_xmit_callback(struct urb *urb) 454 { 455 struct gs_tx_context *txc = urb->context; 456 struct gs_can *dev = txc->dev; 457 struct net_device *netdev = dev->netdev; 458 459 if (urb->status) 460 netdev_info(netdev, "usb xmit fail %u\n", txc->echo_id); 461 462 usb_free_coherent(urb->dev, 463 urb->transfer_buffer_length, 464 urb->transfer_buffer, 465 urb->transfer_dma); 466 } 467 468 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb, 469 struct net_device *netdev) 470 { 471 struct gs_can *dev = netdev_priv(netdev); 472 struct net_device_stats *stats = &dev->netdev->stats; 473 struct urb *urb; 474 struct gs_host_frame *hf; 475 struct can_frame *cf; 476 int rc; 477 unsigned int idx; 478 struct gs_tx_context *txc; 479 480 if (can_dropped_invalid_skb(netdev, skb)) 481 return NETDEV_TX_OK; 482 483 /* find an empty context to keep track of transmission */ 484 txc = gs_alloc_tx_context(dev); 485 if (!txc) 486 return NETDEV_TX_BUSY; 487 488 /* create a URB, and a buffer for it */ 489 urb = usb_alloc_urb(0, GFP_ATOMIC); 490 if (!urb) 491 goto nomem_urb; 492 493 hf = usb_alloc_coherent(dev->udev, sizeof(*hf), GFP_ATOMIC, 494 &urb->transfer_dma); 495 if (!hf) { 496 netdev_err(netdev, "No memory left for USB buffer\n"); 497 goto nomem_hf; 498 } 499 500 idx = txc->echo_id; 501 502 if (idx >= GS_MAX_TX_URBS) { 503 netdev_err(netdev, "Invalid tx context %u\n", idx); 504 goto badidx; 505 } 506 507 hf->echo_id = idx; 508 hf->channel = dev->channel; 509 510 cf = (struct can_frame *)skb->data; 511 512 hf->can_id = cpu_to_le32(cf->can_id); 513 hf->can_dlc = can_get_cc_dlc(cf, dev->can.ctrlmode); 514 515 memcpy(hf->data, cf->data, cf->len); 516 517 usb_fill_bulk_urb(urb, dev->udev, 518 usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT), 519 hf, 520 sizeof(*hf), 521 gs_usb_xmit_callback, 522 txc); 523 524 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 525 usb_anchor_urb(urb, &dev->tx_submitted); 526 527 can_put_echo_skb(skb, netdev, idx, 0); 528 529 atomic_inc(&dev->active_tx_urbs); 530 531 rc = usb_submit_urb(urb, GFP_ATOMIC); 532 if (unlikely(rc)) { /* usb send failed */ 533 atomic_dec(&dev->active_tx_urbs); 534 535 can_free_echo_skb(netdev, idx, NULL); 536 gs_free_tx_context(txc); 537 538 usb_unanchor_urb(urb); 539 usb_free_coherent(dev->udev, 540 sizeof(*hf), 541 hf, 542 urb->transfer_dma); 543 544 if (rc == -ENODEV) { 545 netif_device_detach(netdev); 546 } else { 547 netdev_err(netdev, "usb_submit failed (err=%d)\n", rc); 548 stats->tx_dropped++; 549 } 550 } else { 551 /* Slow down tx path */ 552 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS) 553 netif_stop_queue(netdev); 554 } 555 556 /* let usb core take care of this urb */ 557 usb_free_urb(urb); 558 559 return NETDEV_TX_OK; 560 561 badidx: 562 usb_free_coherent(dev->udev, 563 sizeof(*hf), 564 hf, 565 urb->transfer_dma); 566 nomem_hf: 567 usb_free_urb(urb); 568 569 nomem_urb: 570 gs_free_tx_context(txc); 571 dev_kfree_skb(skb); 572 stats->tx_dropped++; 573 return NETDEV_TX_OK; 574 } 575 576 static int gs_can_open(struct net_device *netdev) 577 { 578 struct gs_can *dev = netdev_priv(netdev); 579 struct gs_usb *parent = dev->parent; 580 int rc, i; 581 struct gs_device_mode *dm; 582 u32 ctrlmode; 583 u32 flags = 0; 584 585 rc = open_candev(netdev); 586 if (rc) 587 return rc; 588 589 if (atomic_add_return(1, &parent->active_channels) == 1) { 590 for (i = 0; i < GS_MAX_RX_URBS; i++) { 591 struct urb *urb; 592 u8 *buf; 593 594 /* alloc rx urb */ 595 urb = usb_alloc_urb(0, GFP_KERNEL); 596 if (!urb) 597 return -ENOMEM; 598 599 /* alloc rx buffer */ 600 buf = usb_alloc_coherent(dev->udev, 601 sizeof(struct gs_host_frame), 602 GFP_KERNEL, 603 &urb->transfer_dma); 604 if (!buf) { 605 netdev_err(netdev, 606 "No memory left for USB buffer\n"); 607 usb_free_urb(urb); 608 return -ENOMEM; 609 } 610 611 /* fill, anchor, and submit rx urb */ 612 usb_fill_bulk_urb(urb, 613 dev->udev, 614 usb_rcvbulkpipe(dev->udev, 615 GSUSB_ENDPOINT_IN), 616 buf, 617 sizeof(struct gs_host_frame), 618 gs_usb_receive_bulk_callback, 619 parent); 620 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 621 622 usb_anchor_urb(urb, &parent->rx_submitted); 623 624 rc = usb_submit_urb(urb, GFP_KERNEL); 625 if (rc) { 626 if (rc == -ENODEV) 627 netif_device_detach(dev->netdev); 628 629 netdev_err(netdev, 630 "usb_submit failed (err=%d)\n", 631 rc); 632 633 usb_unanchor_urb(urb); 634 usb_free_urb(urb); 635 break; 636 } 637 638 /* Drop reference, 639 * USB core will take care of freeing it 640 */ 641 usb_free_urb(urb); 642 } 643 } 644 645 dm = kmalloc(sizeof(*dm), GFP_KERNEL); 646 if (!dm) 647 return -ENOMEM; 648 649 /* flags */ 650 ctrlmode = dev->can.ctrlmode; 651 652 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 653 flags |= GS_CAN_MODE_LOOP_BACK; 654 else if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 655 flags |= GS_CAN_MODE_LISTEN_ONLY; 656 657 /* Controller is not allowed to retry TX 658 * this mode is unavailable on atmels uc3c hardware 659 */ 660 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) 661 flags |= GS_CAN_MODE_ONE_SHOT; 662 663 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES) 664 flags |= GS_CAN_MODE_TRIPLE_SAMPLE; 665 666 /* finally start device */ 667 dm->mode = cpu_to_le32(GS_CAN_MODE_START); 668 dm->flags = cpu_to_le32(flags); 669 rc = usb_control_msg(interface_to_usbdev(dev->iface), 670 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 0), 671 GS_USB_BREQ_MODE, 672 USB_DIR_OUT | USB_TYPE_VENDOR | 673 USB_RECIP_INTERFACE, 674 dev->channel, 675 0, 676 dm, 677 sizeof(*dm), 678 1000); 679 680 if (rc < 0) { 681 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc); 682 kfree(dm); 683 return rc; 684 } 685 686 kfree(dm); 687 688 dev->can.state = CAN_STATE_ERROR_ACTIVE; 689 690 if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)) 691 netif_start_queue(netdev); 692 693 return 0; 694 } 695 696 static int gs_can_close(struct net_device *netdev) 697 { 698 int rc; 699 struct gs_can *dev = netdev_priv(netdev); 700 struct gs_usb *parent = dev->parent; 701 702 netif_stop_queue(netdev); 703 704 /* Stop polling */ 705 if (atomic_dec_and_test(&parent->active_channels)) 706 usb_kill_anchored_urbs(&parent->rx_submitted); 707 708 /* Stop sending URBs */ 709 usb_kill_anchored_urbs(&dev->tx_submitted); 710 atomic_set(&dev->active_tx_urbs, 0); 711 712 /* reset the device */ 713 rc = gs_cmd_reset(dev); 714 if (rc < 0) 715 netdev_warn(netdev, "Couldn't shutdown device (err=%d)", rc); 716 717 /* reset tx contexts */ 718 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 719 dev->tx_context[rc].dev = dev; 720 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 721 } 722 723 /* close the netdev */ 724 close_candev(netdev); 725 726 return 0; 727 } 728 729 static const struct net_device_ops gs_usb_netdev_ops = { 730 .ndo_open = gs_can_open, 731 .ndo_stop = gs_can_close, 732 .ndo_start_xmit = gs_can_start_xmit, 733 .ndo_change_mtu = can_change_mtu, 734 }; 735 736 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify) 737 { 738 struct gs_can *dev = netdev_priv(netdev); 739 struct gs_identify_mode *imode; 740 int rc; 741 742 imode = kmalloc(sizeof(*imode), GFP_KERNEL); 743 744 if (!imode) 745 return -ENOMEM; 746 747 if (do_identify) 748 imode->mode = cpu_to_le32(GS_CAN_IDENTIFY_ON); 749 else 750 imode->mode = cpu_to_le32(GS_CAN_IDENTIFY_OFF); 751 752 rc = usb_control_msg(interface_to_usbdev(dev->iface), 753 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 754 0), 755 GS_USB_BREQ_IDENTIFY, 756 USB_DIR_OUT | USB_TYPE_VENDOR | 757 USB_RECIP_INTERFACE, 758 dev->channel, 759 0, 760 imode, 761 sizeof(*imode), 762 100); 763 764 kfree(imode); 765 766 return (rc > 0) ? 0 : rc; 767 } 768 769 /* blink LED's for finding the this interface */ 770 static int gs_usb_set_phys_id(struct net_device *dev, 771 enum ethtool_phys_id_state state) 772 { 773 int rc = 0; 774 775 switch (state) { 776 case ETHTOOL_ID_ACTIVE: 777 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_ON); 778 break; 779 case ETHTOOL_ID_INACTIVE: 780 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_OFF); 781 break; 782 default: 783 break; 784 } 785 786 return rc; 787 } 788 789 static const struct ethtool_ops gs_usb_ethtool_ops = { 790 .set_phys_id = gs_usb_set_phys_id, 791 }; 792 793 static struct gs_can *gs_make_candev(unsigned int channel, 794 struct usb_interface *intf, 795 struct gs_device_config *dconf) 796 { 797 struct gs_can *dev; 798 struct net_device *netdev; 799 int rc; 800 struct gs_device_bt_const *bt_const; 801 u32 feature; 802 803 bt_const = kmalloc(sizeof(*bt_const), GFP_KERNEL); 804 if (!bt_const) 805 return ERR_PTR(-ENOMEM); 806 807 /* fetch bit timing constants */ 808 rc = usb_control_msg(interface_to_usbdev(intf), 809 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 810 GS_USB_BREQ_BT_CONST, 811 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 812 channel, 813 0, 814 bt_const, 815 sizeof(*bt_const), 816 1000); 817 818 if (rc < 0) { 819 dev_err(&intf->dev, 820 "Couldn't get bit timing const for channel (err=%d)\n", 821 rc); 822 kfree(bt_const); 823 return ERR_PTR(rc); 824 } 825 826 /* create netdev */ 827 netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS); 828 if (!netdev) { 829 dev_err(&intf->dev, "Couldn't allocate candev\n"); 830 kfree(bt_const); 831 return ERR_PTR(-ENOMEM); 832 } 833 834 dev = netdev_priv(netdev); 835 836 netdev->netdev_ops = &gs_usb_netdev_ops; 837 838 netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */ 839 840 /* dev setup */ 841 strcpy(dev->bt_const.name, "gs_usb"); 842 dev->bt_const.tseg1_min = le32_to_cpu(bt_const->tseg1_min); 843 dev->bt_const.tseg1_max = le32_to_cpu(bt_const->tseg1_max); 844 dev->bt_const.tseg2_min = le32_to_cpu(bt_const->tseg2_min); 845 dev->bt_const.tseg2_max = le32_to_cpu(bt_const->tseg2_max); 846 dev->bt_const.sjw_max = le32_to_cpu(bt_const->sjw_max); 847 dev->bt_const.brp_min = le32_to_cpu(bt_const->brp_min); 848 dev->bt_const.brp_max = le32_to_cpu(bt_const->brp_max); 849 dev->bt_const.brp_inc = le32_to_cpu(bt_const->brp_inc); 850 851 dev->udev = interface_to_usbdev(intf); 852 dev->iface = intf; 853 dev->netdev = netdev; 854 dev->channel = channel; 855 856 init_usb_anchor(&dev->tx_submitted); 857 atomic_set(&dev->active_tx_urbs, 0); 858 spin_lock_init(&dev->tx_ctx_lock); 859 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 860 dev->tx_context[rc].dev = dev; 861 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 862 } 863 864 /* can setup */ 865 dev->can.state = CAN_STATE_STOPPED; 866 dev->can.clock.freq = le32_to_cpu(bt_const->fclk_can); 867 dev->can.bittiming_const = &dev->bt_const; 868 dev->can.do_set_bittiming = gs_usb_set_bittiming; 869 870 dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC; 871 872 feature = le32_to_cpu(bt_const->feature); 873 if (feature & GS_CAN_FEATURE_LISTEN_ONLY) 874 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY; 875 876 if (feature & GS_CAN_FEATURE_LOOP_BACK) 877 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK; 878 879 if (feature & GS_CAN_FEATURE_TRIPLE_SAMPLE) 880 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; 881 882 if (feature & GS_CAN_FEATURE_ONE_SHOT) 883 dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT; 884 885 SET_NETDEV_DEV(netdev, &intf->dev); 886 887 if (le32_to_cpu(dconf->sw_version) > 1) 888 if (feature & GS_CAN_FEATURE_IDENTIFY) 889 netdev->ethtool_ops = &gs_usb_ethtool_ops; 890 891 kfree(bt_const); 892 893 rc = register_candev(dev->netdev); 894 if (rc) { 895 free_candev(dev->netdev); 896 dev_err(&intf->dev, "Couldn't register candev (err=%d)\n", rc); 897 return ERR_PTR(rc); 898 } 899 900 return dev; 901 } 902 903 static void gs_destroy_candev(struct gs_can *dev) 904 { 905 unregister_candev(dev->netdev); 906 usb_kill_anchored_urbs(&dev->tx_submitted); 907 free_candev(dev->netdev); 908 } 909 910 static int gs_usb_probe(struct usb_interface *intf, 911 const struct usb_device_id *id) 912 { 913 struct gs_usb *dev; 914 int rc = -ENOMEM; 915 unsigned int icount, i; 916 struct gs_host_config *hconf; 917 struct gs_device_config *dconf; 918 919 hconf = kmalloc(sizeof(*hconf), GFP_KERNEL); 920 if (!hconf) 921 return -ENOMEM; 922 923 hconf->byte_order = cpu_to_le32(0x0000beef); 924 925 /* send host config */ 926 rc = usb_control_msg(interface_to_usbdev(intf), 927 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 928 GS_USB_BREQ_HOST_FORMAT, 929 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 930 1, 931 intf->cur_altsetting->desc.bInterfaceNumber, 932 hconf, 933 sizeof(*hconf), 934 1000); 935 936 kfree(hconf); 937 938 if (rc < 0) { 939 dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", 940 rc); 941 return rc; 942 } 943 944 dconf = kmalloc(sizeof(*dconf), GFP_KERNEL); 945 if (!dconf) 946 return -ENOMEM; 947 948 /* read device config */ 949 rc = usb_control_msg(interface_to_usbdev(intf), 950 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 951 GS_USB_BREQ_DEVICE_CONFIG, 952 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 953 1, 954 intf->cur_altsetting->desc.bInterfaceNumber, 955 dconf, 956 sizeof(*dconf), 957 1000); 958 if (rc < 0) { 959 dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n", 960 rc); 961 kfree(dconf); 962 return rc; 963 } 964 965 icount = dconf->icount + 1; 966 dev_info(&intf->dev, "Configuring for %u interfaces\n", icount); 967 968 if (icount > GS_MAX_INTF) { 969 dev_err(&intf->dev, 970 "Driver cannot handle more that %u CAN interfaces\n", 971 GS_MAX_INTF); 972 kfree(dconf); 973 return -EINVAL; 974 } 975 976 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 977 if (!dev) { 978 kfree(dconf); 979 return -ENOMEM; 980 } 981 982 init_usb_anchor(&dev->rx_submitted); 983 984 atomic_set(&dev->active_channels, 0); 985 986 usb_set_intfdata(intf, dev); 987 dev->udev = interface_to_usbdev(intf); 988 989 for (i = 0; i < icount; i++) { 990 dev->canch[i] = gs_make_candev(i, intf, dconf); 991 if (IS_ERR_OR_NULL(dev->canch[i])) { 992 /* save error code to return later */ 993 rc = PTR_ERR(dev->canch[i]); 994 995 /* on failure destroy previously created candevs */ 996 icount = i; 997 for (i = 0; i < icount; i++) 998 gs_destroy_candev(dev->canch[i]); 999 1000 usb_kill_anchored_urbs(&dev->rx_submitted); 1001 kfree(dconf); 1002 kfree(dev); 1003 return rc; 1004 } 1005 dev->canch[i]->parent = dev; 1006 } 1007 1008 kfree(dconf); 1009 1010 return 0; 1011 } 1012 1013 static void gs_usb_disconnect(struct usb_interface *intf) 1014 { 1015 unsigned i; 1016 struct gs_usb *dev = usb_get_intfdata(intf); 1017 usb_set_intfdata(intf, NULL); 1018 1019 if (!dev) { 1020 dev_err(&intf->dev, "Disconnect (nodata)\n"); 1021 return; 1022 } 1023 1024 for (i = 0; i < GS_MAX_INTF; i++) 1025 if (dev->canch[i]) 1026 gs_destroy_candev(dev->canch[i]); 1027 1028 usb_kill_anchored_urbs(&dev->rx_submitted); 1029 kfree(dev); 1030 } 1031 1032 static const struct usb_device_id gs_usb_table[] = { 1033 { USB_DEVICE_INTERFACE_NUMBER(USB_GSUSB_1_VENDOR_ID, 1034 USB_GSUSB_1_PRODUCT_ID, 0) }, 1035 { USB_DEVICE_INTERFACE_NUMBER(USB_CANDLELIGHT_VENDOR_ID, 1036 USB_CANDLELIGHT_PRODUCT_ID, 0) }, 1037 {} /* Terminating entry */ 1038 }; 1039 1040 MODULE_DEVICE_TABLE(usb, gs_usb_table); 1041 1042 static struct usb_driver gs_usb_driver = { 1043 .name = "gs_usb", 1044 .probe = gs_usb_probe, 1045 .disconnect = gs_usb_disconnect, 1046 .id_table = gs_usb_table, 1047 }; 1048 1049 module_usb_driver(gs_usb_driver); 1050 1051 MODULE_AUTHOR("Maximilian Schneider <mws@schneidersoft.net>"); 1052 MODULE_DESCRIPTION( 1053 "Socket CAN device driver for Geschwister Schneider Technologie-, " 1054 "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces\n" 1055 "and bytewerk.org candleLight USB CAN interfaces."); 1056 MODULE_LICENSE("GPL v2"); 1057