1 /* CAN driver for Geschwister Schneider USB/CAN devices 2 * and bytewerk.org candleLight USB CAN interfaces. 3 * 4 * Copyright (C) 2013-2016 Geschwister Schneider Technologie-, 5 * Entwicklungs- und Vertriebs UG (Haftungsbeschränkt). 6 * Copyright (C) 2016 Hubert Denkmair 7 * 8 * Many thanks to all socketcan devs! 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published 12 * by the Free Software Foundation; version 2 of the License. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 */ 19 20 #include <linux/init.h> 21 #include <linux/signal.h> 22 #include <linux/module.h> 23 #include <linux/netdevice.h> 24 #include <linux/usb.h> 25 26 #include <linux/can.h> 27 #include <linux/can/dev.h> 28 #include <linux/can/error.h> 29 30 /* Device specific constants */ 31 #define USB_GSUSB_1_VENDOR_ID 0x1d50 32 #define USB_GSUSB_1_PRODUCT_ID 0x606f 33 34 #define USB_CANDLELIGHT_VENDOR_ID 0x1209 35 #define USB_CANDLELIGHT_PRODUCT_ID 0x2323 36 37 #define GSUSB_ENDPOINT_IN 1 38 #define GSUSB_ENDPOINT_OUT 2 39 40 /* Device specific constants */ 41 enum gs_usb_breq { 42 GS_USB_BREQ_HOST_FORMAT = 0, 43 GS_USB_BREQ_BITTIMING, 44 GS_USB_BREQ_MODE, 45 GS_USB_BREQ_BERR, 46 GS_USB_BREQ_BT_CONST, 47 GS_USB_BREQ_DEVICE_CONFIG, 48 GS_USB_BREQ_TIMESTAMP, 49 GS_USB_BREQ_IDENTIFY, 50 }; 51 52 enum gs_can_mode { 53 /* reset a channel. turns it off */ 54 GS_CAN_MODE_RESET = 0, 55 /* starts a channel */ 56 GS_CAN_MODE_START 57 }; 58 59 enum gs_can_state { 60 GS_CAN_STATE_ERROR_ACTIVE = 0, 61 GS_CAN_STATE_ERROR_WARNING, 62 GS_CAN_STATE_ERROR_PASSIVE, 63 GS_CAN_STATE_BUS_OFF, 64 GS_CAN_STATE_STOPPED, 65 GS_CAN_STATE_SLEEPING 66 }; 67 68 enum gs_can_identify_mode { 69 GS_CAN_IDENTIFY_OFF = 0, 70 GS_CAN_IDENTIFY_ON 71 }; 72 73 /* data types passed between host and device */ 74 struct gs_host_config { 75 u32 byte_order; 76 } __packed; 77 /* All data exchanged between host and device is exchanged in host byte order, 78 * thanks to the struct gs_host_config byte_order member, which is sent first 79 * to indicate the desired byte order. 80 */ 81 82 struct gs_device_config { 83 u8 reserved1; 84 u8 reserved2; 85 u8 reserved3; 86 u8 icount; 87 u32 sw_version; 88 u32 hw_version; 89 } __packed; 90 91 #define GS_CAN_MODE_NORMAL 0 92 #define GS_CAN_MODE_LISTEN_ONLY BIT(0) 93 #define GS_CAN_MODE_LOOP_BACK BIT(1) 94 #define GS_CAN_MODE_TRIPLE_SAMPLE BIT(2) 95 #define GS_CAN_MODE_ONE_SHOT BIT(3) 96 97 struct gs_device_mode { 98 u32 mode; 99 u32 flags; 100 } __packed; 101 102 struct gs_device_state { 103 u32 state; 104 u32 rxerr; 105 u32 txerr; 106 } __packed; 107 108 struct gs_device_bittiming { 109 u32 prop_seg; 110 u32 phase_seg1; 111 u32 phase_seg2; 112 u32 sjw; 113 u32 brp; 114 } __packed; 115 116 struct gs_identify_mode { 117 u32 mode; 118 } __packed; 119 120 #define GS_CAN_FEATURE_LISTEN_ONLY BIT(0) 121 #define GS_CAN_FEATURE_LOOP_BACK BIT(1) 122 #define GS_CAN_FEATURE_TRIPLE_SAMPLE BIT(2) 123 #define GS_CAN_FEATURE_ONE_SHOT BIT(3) 124 #define GS_CAN_FEATURE_HW_TIMESTAMP BIT(4) 125 #define GS_CAN_FEATURE_IDENTIFY BIT(5) 126 127 struct gs_device_bt_const { 128 u32 feature; 129 u32 fclk_can; 130 u32 tseg1_min; 131 u32 tseg1_max; 132 u32 tseg2_min; 133 u32 tseg2_max; 134 u32 sjw_max; 135 u32 brp_min; 136 u32 brp_max; 137 u32 brp_inc; 138 } __packed; 139 140 #define GS_CAN_FLAG_OVERFLOW 1 141 142 struct gs_host_frame { 143 u32 echo_id; 144 u32 can_id; 145 146 u8 can_dlc; 147 u8 channel; 148 u8 flags; 149 u8 reserved; 150 151 u8 data[8]; 152 } __packed; 153 /* The GS USB devices make use of the same flags and masks as in 154 * linux/can.h and linux/can/error.h, and no additional mapping is necessary. 155 */ 156 157 /* Only send a max of GS_MAX_TX_URBS frames per channel at a time. */ 158 #define GS_MAX_TX_URBS 10 159 /* Only launch a max of GS_MAX_RX_URBS usb requests at a time. */ 160 #define GS_MAX_RX_URBS 30 161 /* Maximum number of interfaces the driver supports per device. 162 * Current hardware only supports 2 interfaces. The future may vary. 163 */ 164 #define GS_MAX_INTF 2 165 166 struct gs_tx_context { 167 struct gs_can *dev; 168 unsigned int echo_id; 169 }; 170 171 struct gs_can { 172 struct can_priv can; /* must be the first member */ 173 174 struct gs_usb *parent; 175 176 struct net_device *netdev; 177 struct usb_device *udev; 178 struct usb_interface *iface; 179 180 struct can_bittiming_const bt_const; 181 unsigned int channel; /* channel number */ 182 183 /* This lock prevents a race condition between xmit and receive. */ 184 spinlock_t tx_ctx_lock; 185 struct gs_tx_context tx_context[GS_MAX_TX_URBS]; 186 187 struct usb_anchor tx_submitted; 188 atomic_t active_tx_urbs; 189 }; 190 191 /* usb interface struct */ 192 struct gs_usb { 193 struct gs_can *canch[GS_MAX_INTF]; 194 struct usb_anchor rx_submitted; 195 atomic_t active_channels; 196 struct usb_device *udev; 197 }; 198 199 /* 'allocate' a tx context. 200 * returns a valid tx context or NULL if there is no space. 201 */ 202 static struct gs_tx_context *gs_alloc_tx_context(struct gs_can *dev) 203 { 204 int i = 0; 205 unsigned long flags; 206 207 spin_lock_irqsave(&dev->tx_ctx_lock, flags); 208 209 for (; i < GS_MAX_TX_URBS; i++) { 210 if (dev->tx_context[i].echo_id == GS_MAX_TX_URBS) { 211 dev->tx_context[i].echo_id = i; 212 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 213 return &dev->tx_context[i]; 214 } 215 } 216 217 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 218 return NULL; 219 } 220 221 /* releases a tx context 222 */ 223 static void gs_free_tx_context(struct gs_tx_context *txc) 224 { 225 txc->echo_id = GS_MAX_TX_URBS; 226 } 227 228 /* Get a tx context by id. 229 */ 230 static struct gs_tx_context *gs_get_tx_context(struct gs_can *dev, 231 unsigned int id) 232 { 233 unsigned long flags; 234 235 if (id < GS_MAX_TX_URBS) { 236 spin_lock_irqsave(&dev->tx_ctx_lock, flags); 237 if (dev->tx_context[id].echo_id == id) { 238 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 239 return &dev->tx_context[id]; 240 } 241 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 242 } 243 return NULL; 244 } 245 246 static int gs_cmd_reset(struct gs_usb *gsusb, struct gs_can *gsdev) 247 { 248 struct gs_device_mode *dm; 249 struct usb_interface *intf = gsdev->iface; 250 int rc; 251 252 dm = kzalloc(sizeof(*dm), GFP_KERNEL); 253 if (!dm) 254 return -ENOMEM; 255 256 dm->mode = GS_CAN_MODE_RESET; 257 258 rc = usb_control_msg(interface_to_usbdev(intf), 259 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 260 GS_USB_BREQ_MODE, 261 USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 262 gsdev->channel, 263 0, 264 dm, 265 sizeof(*dm), 266 1000); 267 268 return rc; 269 } 270 271 static void gs_update_state(struct gs_can *dev, struct can_frame *cf) 272 { 273 struct can_device_stats *can_stats = &dev->can.can_stats; 274 275 if (cf->can_id & CAN_ERR_RESTARTED) { 276 dev->can.state = CAN_STATE_ERROR_ACTIVE; 277 can_stats->restarts++; 278 } else if (cf->can_id & CAN_ERR_BUSOFF) { 279 dev->can.state = CAN_STATE_BUS_OFF; 280 can_stats->bus_off++; 281 } else if (cf->can_id & CAN_ERR_CRTL) { 282 if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) || 283 (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) { 284 dev->can.state = CAN_STATE_ERROR_WARNING; 285 can_stats->error_warning++; 286 } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) || 287 (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) { 288 dev->can.state = CAN_STATE_ERROR_PASSIVE; 289 can_stats->error_passive++; 290 } else { 291 dev->can.state = CAN_STATE_ERROR_ACTIVE; 292 } 293 } 294 } 295 296 static void gs_usb_receive_bulk_callback(struct urb *urb) 297 { 298 struct gs_usb *usbcan = urb->context; 299 struct gs_can *dev; 300 struct net_device *netdev; 301 int rc; 302 struct net_device_stats *stats; 303 struct gs_host_frame *hf = urb->transfer_buffer; 304 struct gs_tx_context *txc; 305 struct can_frame *cf; 306 struct sk_buff *skb; 307 308 BUG_ON(!usbcan); 309 310 switch (urb->status) { 311 case 0: /* success */ 312 break; 313 case -ENOENT: 314 case -ESHUTDOWN: 315 return; 316 default: 317 /* do not resubmit aborted urbs. eg: when device goes down */ 318 return; 319 } 320 321 /* device reports out of range channel id */ 322 if (hf->channel >= GS_MAX_INTF) 323 goto resubmit_urb; 324 325 dev = usbcan->canch[hf->channel]; 326 327 netdev = dev->netdev; 328 stats = &netdev->stats; 329 330 if (!netif_device_present(netdev)) 331 return; 332 333 if (hf->echo_id == -1) { /* normal rx */ 334 skb = alloc_can_skb(dev->netdev, &cf); 335 if (!skb) 336 return; 337 338 cf->can_id = hf->can_id; 339 340 cf->can_dlc = get_can_dlc(hf->can_dlc); 341 memcpy(cf->data, hf->data, 8); 342 343 /* ERROR frames tell us information about the controller */ 344 if (hf->can_id & CAN_ERR_FLAG) 345 gs_update_state(dev, cf); 346 347 netdev->stats.rx_packets++; 348 netdev->stats.rx_bytes += hf->can_dlc; 349 350 netif_rx(skb); 351 } else { /* echo_id == hf->echo_id */ 352 if (hf->echo_id >= GS_MAX_TX_URBS) { 353 netdev_err(netdev, 354 "Unexpected out of range echo id %d\n", 355 hf->echo_id); 356 goto resubmit_urb; 357 } 358 359 netdev->stats.tx_packets++; 360 netdev->stats.tx_bytes += hf->can_dlc; 361 362 txc = gs_get_tx_context(dev, hf->echo_id); 363 364 /* bad devices send bad echo_ids. */ 365 if (!txc) { 366 netdev_err(netdev, 367 "Unexpected unused echo id %d\n", 368 hf->echo_id); 369 goto resubmit_urb; 370 } 371 372 can_get_echo_skb(netdev, hf->echo_id); 373 374 gs_free_tx_context(txc); 375 376 netif_wake_queue(netdev); 377 } 378 379 if (hf->flags & GS_CAN_FLAG_OVERFLOW) { 380 skb = alloc_can_err_skb(netdev, &cf); 381 if (!skb) 382 goto resubmit_urb; 383 384 cf->can_id |= CAN_ERR_CRTL; 385 cf->can_dlc = CAN_ERR_DLC; 386 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 387 stats->rx_over_errors++; 388 stats->rx_errors++; 389 netif_rx(skb); 390 } 391 392 resubmit_urb: 393 usb_fill_bulk_urb(urb, 394 usbcan->udev, 395 usb_rcvbulkpipe(usbcan->udev, GSUSB_ENDPOINT_IN), 396 hf, 397 sizeof(struct gs_host_frame), 398 gs_usb_receive_bulk_callback, 399 usbcan 400 ); 401 402 rc = usb_submit_urb(urb, GFP_ATOMIC); 403 404 /* USB failure take down all interfaces */ 405 if (rc == -ENODEV) { 406 for (rc = 0; rc < GS_MAX_INTF; rc++) { 407 if (usbcan->canch[rc]) 408 netif_device_detach(usbcan->canch[rc]->netdev); 409 } 410 } 411 } 412 413 static int gs_usb_set_bittiming(struct net_device *netdev) 414 { 415 struct gs_can *dev = netdev_priv(netdev); 416 struct can_bittiming *bt = &dev->can.bittiming; 417 struct usb_interface *intf = dev->iface; 418 int rc; 419 struct gs_device_bittiming *dbt; 420 421 dbt = kmalloc(sizeof(*dbt), GFP_KERNEL); 422 if (!dbt) 423 return -ENOMEM; 424 425 dbt->prop_seg = bt->prop_seg; 426 dbt->phase_seg1 = bt->phase_seg1; 427 dbt->phase_seg2 = bt->phase_seg2; 428 dbt->sjw = bt->sjw; 429 dbt->brp = bt->brp; 430 431 /* request bit timings */ 432 rc = usb_control_msg(interface_to_usbdev(intf), 433 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 434 GS_USB_BREQ_BITTIMING, 435 USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 436 dev->channel, 437 0, 438 dbt, 439 sizeof(*dbt), 440 1000); 441 442 kfree(dbt); 443 444 if (rc < 0) 445 dev_err(netdev->dev.parent, "Couldn't set bittimings (err=%d)", 446 rc); 447 448 return rc; 449 } 450 451 static void gs_usb_xmit_callback(struct urb *urb) 452 { 453 struct gs_tx_context *txc = urb->context; 454 struct gs_can *dev = txc->dev; 455 struct net_device *netdev = dev->netdev; 456 457 if (urb->status) 458 netdev_info(netdev, "usb xmit fail %d\n", txc->echo_id); 459 460 usb_free_coherent(urb->dev, 461 urb->transfer_buffer_length, 462 urb->transfer_buffer, 463 urb->transfer_dma); 464 465 atomic_dec(&dev->active_tx_urbs); 466 467 if (!netif_device_present(netdev)) 468 return; 469 470 if (netif_queue_stopped(netdev)) 471 netif_wake_queue(netdev); 472 } 473 474 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb, 475 struct net_device *netdev) 476 { 477 struct gs_can *dev = netdev_priv(netdev); 478 struct net_device_stats *stats = &dev->netdev->stats; 479 struct urb *urb; 480 struct gs_host_frame *hf; 481 struct can_frame *cf; 482 int rc; 483 unsigned int idx; 484 struct gs_tx_context *txc; 485 486 if (can_dropped_invalid_skb(netdev, skb)) 487 return NETDEV_TX_OK; 488 489 /* find an empty context to keep track of transmission */ 490 txc = gs_alloc_tx_context(dev); 491 if (!txc) 492 return NETDEV_TX_BUSY; 493 494 /* create a URB, and a buffer for it */ 495 urb = usb_alloc_urb(0, GFP_ATOMIC); 496 if (!urb) 497 goto nomem_urb; 498 499 hf = usb_alloc_coherent(dev->udev, sizeof(*hf), GFP_ATOMIC, 500 &urb->transfer_dma); 501 if (!hf) { 502 netdev_err(netdev, "No memory left for USB buffer\n"); 503 goto nomem_hf; 504 } 505 506 idx = txc->echo_id; 507 508 if (idx >= GS_MAX_TX_URBS) { 509 netdev_err(netdev, "Invalid tx context %d\n", idx); 510 goto badidx; 511 } 512 513 hf->echo_id = idx; 514 hf->channel = dev->channel; 515 516 cf = (struct can_frame *)skb->data; 517 518 hf->can_id = cf->can_id; 519 hf->can_dlc = cf->can_dlc; 520 memcpy(hf->data, cf->data, cf->can_dlc); 521 522 usb_fill_bulk_urb(urb, dev->udev, 523 usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT), 524 hf, 525 sizeof(*hf), 526 gs_usb_xmit_callback, 527 txc); 528 529 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 530 usb_anchor_urb(urb, &dev->tx_submitted); 531 532 can_put_echo_skb(skb, netdev, idx); 533 534 atomic_inc(&dev->active_tx_urbs); 535 536 rc = usb_submit_urb(urb, GFP_ATOMIC); 537 if (unlikely(rc)) { /* usb send failed */ 538 atomic_dec(&dev->active_tx_urbs); 539 540 can_free_echo_skb(netdev, idx); 541 gs_free_tx_context(txc); 542 543 usb_unanchor_urb(urb); 544 usb_free_coherent(dev->udev, 545 sizeof(*hf), 546 hf, 547 urb->transfer_dma); 548 549 550 if (rc == -ENODEV) { 551 netif_device_detach(netdev); 552 } else { 553 netdev_err(netdev, "usb_submit failed (err=%d)\n", rc); 554 stats->tx_dropped++; 555 } 556 } else { 557 /* Slow down tx path */ 558 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS) 559 netif_stop_queue(netdev); 560 } 561 562 /* let usb core take care of this urb */ 563 usb_free_urb(urb); 564 565 return NETDEV_TX_OK; 566 567 badidx: 568 usb_free_coherent(dev->udev, 569 sizeof(*hf), 570 hf, 571 urb->transfer_dma); 572 nomem_hf: 573 usb_free_urb(urb); 574 575 nomem_urb: 576 gs_free_tx_context(txc); 577 dev_kfree_skb(skb); 578 stats->tx_dropped++; 579 return NETDEV_TX_OK; 580 } 581 582 static int gs_can_open(struct net_device *netdev) 583 { 584 struct gs_can *dev = netdev_priv(netdev); 585 struct gs_usb *parent = dev->parent; 586 int rc, i; 587 struct gs_device_mode *dm; 588 u32 ctrlmode; 589 590 rc = open_candev(netdev); 591 if (rc) 592 return rc; 593 594 if (atomic_add_return(1, &parent->active_channels) == 1) { 595 for (i = 0; i < GS_MAX_RX_URBS; i++) { 596 struct urb *urb; 597 u8 *buf; 598 599 /* alloc rx urb */ 600 urb = usb_alloc_urb(0, GFP_KERNEL); 601 if (!urb) 602 return -ENOMEM; 603 604 /* alloc rx buffer */ 605 buf = usb_alloc_coherent(dev->udev, 606 sizeof(struct gs_host_frame), 607 GFP_KERNEL, 608 &urb->transfer_dma); 609 if (!buf) { 610 netdev_err(netdev, 611 "No memory left for USB buffer\n"); 612 usb_free_urb(urb); 613 return -ENOMEM; 614 } 615 616 /* fill, anchor, and submit rx urb */ 617 usb_fill_bulk_urb(urb, 618 dev->udev, 619 usb_rcvbulkpipe(dev->udev, 620 GSUSB_ENDPOINT_IN), 621 buf, 622 sizeof(struct gs_host_frame), 623 gs_usb_receive_bulk_callback, 624 parent); 625 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 626 627 usb_anchor_urb(urb, &parent->rx_submitted); 628 629 rc = usb_submit_urb(urb, GFP_KERNEL); 630 if (rc) { 631 if (rc == -ENODEV) 632 netif_device_detach(dev->netdev); 633 634 netdev_err(netdev, 635 "usb_submit failed (err=%d)\n", 636 rc); 637 638 usb_unanchor_urb(urb); 639 break; 640 } 641 642 /* Drop reference, 643 * USB core will take care of freeing it 644 */ 645 usb_free_urb(urb); 646 } 647 } 648 649 dm = kmalloc(sizeof(*dm), GFP_KERNEL); 650 if (!dm) 651 return -ENOMEM; 652 653 /* flags */ 654 ctrlmode = dev->can.ctrlmode; 655 dm->flags = 0; 656 657 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 658 dm->flags |= GS_CAN_MODE_LOOP_BACK; 659 else if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 660 dm->flags |= GS_CAN_MODE_LISTEN_ONLY; 661 662 /* Controller is not allowed to retry TX 663 * this mode is unavailable on atmels uc3c hardware 664 */ 665 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) 666 dm->flags |= GS_CAN_MODE_ONE_SHOT; 667 668 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES) 669 dm->flags |= GS_CAN_MODE_TRIPLE_SAMPLE; 670 671 /* finally start device */ 672 dm->mode = GS_CAN_MODE_START; 673 rc = usb_control_msg(interface_to_usbdev(dev->iface), 674 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 0), 675 GS_USB_BREQ_MODE, 676 USB_DIR_OUT | USB_TYPE_VENDOR | 677 USB_RECIP_INTERFACE, 678 dev->channel, 679 0, 680 dm, 681 sizeof(*dm), 682 1000); 683 684 if (rc < 0) { 685 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc); 686 kfree(dm); 687 return rc; 688 } 689 690 kfree(dm); 691 692 dev->can.state = CAN_STATE_ERROR_ACTIVE; 693 694 if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)) 695 netif_start_queue(netdev); 696 697 return 0; 698 } 699 700 static int gs_can_close(struct net_device *netdev) 701 { 702 int rc; 703 struct gs_can *dev = netdev_priv(netdev); 704 struct gs_usb *parent = dev->parent; 705 706 netif_stop_queue(netdev); 707 708 /* Stop polling */ 709 if (atomic_dec_and_test(&parent->active_channels)) 710 usb_kill_anchored_urbs(&parent->rx_submitted); 711 712 /* Stop sending URBs */ 713 usb_kill_anchored_urbs(&dev->tx_submitted); 714 atomic_set(&dev->active_tx_urbs, 0); 715 716 /* reset the device */ 717 rc = gs_cmd_reset(parent, dev); 718 if (rc < 0) 719 netdev_warn(netdev, "Couldn't shutdown device (err=%d)", rc); 720 721 /* reset tx contexts */ 722 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 723 dev->tx_context[rc].dev = dev; 724 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 725 } 726 727 /* close the netdev */ 728 close_candev(netdev); 729 730 return 0; 731 } 732 733 static const struct net_device_ops gs_usb_netdev_ops = { 734 .ndo_open = gs_can_open, 735 .ndo_stop = gs_can_close, 736 .ndo_start_xmit = gs_can_start_xmit, 737 .ndo_change_mtu = can_change_mtu, 738 }; 739 740 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify) 741 { 742 struct gs_can *dev = netdev_priv(netdev); 743 struct gs_identify_mode imode; 744 int rc; 745 746 if (do_identify) 747 imode.mode = GS_CAN_IDENTIFY_ON; 748 else 749 imode.mode = GS_CAN_IDENTIFY_OFF; 750 751 rc = usb_control_msg(interface_to_usbdev(dev->iface), 752 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 753 0), 754 GS_USB_BREQ_IDENTIFY, 755 USB_DIR_OUT | USB_TYPE_VENDOR | 756 USB_RECIP_INTERFACE, 757 dev->channel, 758 0, 759 &imode, 760 sizeof(imode), 761 100); 762 763 return (rc > 0) ? 0 : rc; 764 } 765 766 /* blink LED's for finding the this interface */ 767 static int gs_usb_set_phys_id(struct net_device *dev, 768 enum ethtool_phys_id_state state) 769 { 770 int rc = 0; 771 772 switch (state) { 773 case ETHTOOL_ID_ACTIVE: 774 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_ON); 775 break; 776 case ETHTOOL_ID_INACTIVE: 777 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_OFF); 778 break; 779 default: 780 break; 781 } 782 783 return rc; 784 } 785 786 static const struct ethtool_ops gs_usb_ethtool_ops = { 787 .set_phys_id = gs_usb_set_phys_id, 788 }; 789 790 static struct gs_can *gs_make_candev(unsigned int channel, 791 struct usb_interface *intf, 792 struct gs_device_config *dconf) 793 { 794 struct gs_can *dev; 795 struct net_device *netdev; 796 int rc; 797 struct gs_device_bt_const *bt_const; 798 799 bt_const = kmalloc(sizeof(*bt_const), GFP_KERNEL); 800 if (!bt_const) 801 return ERR_PTR(-ENOMEM); 802 803 /* fetch bit timing constants */ 804 rc = usb_control_msg(interface_to_usbdev(intf), 805 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 806 GS_USB_BREQ_BT_CONST, 807 USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 808 channel, 809 0, 810 bt_const, 811 sizeof(*bt_const), 812 1000); 813 814 if (rc < 0) { 815 dev_err(&intf->dev, 816 "Couldn't get bit timing const for channel (err=%d)\n", 817 rc); 818 kfree(bt_const); 819 return ERR_PTR(rc); 820 } 821 822 /* create netdev */ 823 netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS); 824 if (!netdev) { 825 dev_err(&intf->dev, "Couldn't allocate candev\n"); 826 kfree(bt_const); 827 return ERR_PTR(-ENOMEM); 828 } 829 830 dev = netdev_priv(netdev); 831 832 netdev->netdev_ops = &gs_usb_netdev_ops; 833 834 netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */ 835 836 /* dev settup */ 837 strcpy(dev->bt_const.name, "gs_usb"); 838 dev->bt_const.tseg1_min = bt_const->tseg1_min; 839 dev->bt_const.tseg1_max = bt_const->tseg1_max; 840 dev->bt_const.tseg2_min = bt_const->tseg2_min; 841 dev->bt_const.tseg2_max = bt_const->tseg2_max; 842 dev->bt_const.sjw_max = bt_const->sjw_max; 843 dev->bt_const.brp_min = bt_const->brp_min; 844 dev->bt_const.brp_max = bt_const->brp_max; 845 dev->bt_const.brp_inc = bt_const->brp_inc; 846 847 dev->udev = interface_to_usbdev(intf); 848 dev->iface = intf; 849 dev->netdev = netdev; 850 dev->channel = channel; 851 852 init_usb_anchor(&dev->tx_submitted); 853 atomic_set(&dev->active_tx_urbs, 0); 854 spin_lock_init(&dev->tx_ctx_lock); 855 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 856 dev->tx_context[rc].dev = dev; 857 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 858 } 859 860 /* can settup */ 861 dev->can.state = CAN_STATE_STOPPED; 862 dev->can.clock.freq = bt_const->fclk_can; 863 dev->can.bittiming_const = &dev->bt_const; 864 dev->can.do_set_bittiming = gs_usb_set_bittiming; 865 866 dev->can.ctrlmode_supported = 0; 867 868 if (bt_const->feature & GS_CAN_FEATURE_LISTEN_ONLY) 869 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY; 870 871 if (bt_const->feature & GS_CAN_FEATURE_LOOP_BACK) 872 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK; 873 874 if (bt_const->feature & GS_CAN_FEATURE_TRIPLE_SAMPLE) 875 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; 876 877 if (bt_const->feature & GS_CAN_FEATURE_ONE_SHOT) 878 dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT; 879 880 SET_NETDEV_DEV(netdev, &intf->dev); 881 882 if (dconf->sw_version > 1) 883 if (bt_const->feature & GS_CAN_FEATURE_IDENTIFY) 884 netdev->ethtool_ops = &gs_usb_ethtool_ops; 885 886 kfree(bt_const); 887 888 rc = register_candev(dev->netdev); 889 if (rc) { 890 free_candev(dev->netdev); 891 dev_err(&intf->dev, "Couldn't register candev (err=%d)\n", rc); 892 return ERR_PTR(rc); 893 } 894 895 return dev; 896 } 897 898 static void gs_destroy_candev(struct gs_can *dev) 899 { 900 unregister_candev(dev->netdev); 901 usb_kill_anchored_urbs(&dev->tx_submitted); 902 free_candev(dev->netdev); 903 } 904 905 static int gs_usb_probe(struct usb_interface *intf, 906 const struct usb_device_id *id) 907 { 908 struct gs_usb *dev; 909 int rc = -ENOMEM; 910 unsigned int icount, i; 911 struct gs_host_config hconf = { 912 .byte_order = 0x0000beef, 913 }; 914 struct gs_device_config dconf; 915 916 /* send host config */ 917 rc = usb_control_msg(interface_to_usbdev(intf), 918 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 919 GS_USB_BREQ_HOST_FORMAT, 920 USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 921 1, 922 intf->altsetting[0].desc.bInterfaceNumber, 923 &hconf, 924 sizeof(hconf), 925 1000); 926 927 if (rc < 0) { 928 dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", 929 rc); 930 return rc; 931 } 932 933 /* read device config */ 934 rc = usb_control_msg(interface_to_usbdev(intf), 935 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 936 GS_USB_BREQ_DEVICE_CONFIG, 937 USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 938 1, 939 intf->altsetting[0].desc.bInterfaceNumber, 940 &dconf, 941 sizeof(dconf), 942 1000); 943 if (rc < 0) { 944 dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n", 945 rc); 946 return rc; 947 } 948 949 icount = dconf.icount + 1; 950 dev_info(&intf->dev, "Configuring for %d interfaces\n", icount); 951 952 if (icount > GS_MAX_INTF) { 953 dev_err(&intf->dev, 954 "Driver cannot handle more that %d CAN interfaces\n", 955 GS_MAX_INTF); 956 return -EINVAL; 957 } 958 959 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 960 if (!dev) 961 return -ENOMEM; 962 init_usb_anchor(&dev->rx_submitted); 963 964 atomic_set(&dev->active_channels, 0); 965 966 usb_set_intfdata(intf, dev); 967 dev->udev = interface_to_usbdev(intf); 968 969 for (i = 0; i < icount; i++) { 970 dev->canch[i] = gs_make_candev(i, intf, &dconf); 971 if (IS_ERR_OR_NULL(dev->canch[i])) { 972 /* save error code to return later */ 973 rc = PTR_ERR(dev->canch[i]); 974 975 /* on failure destroy previously created candevs */ 976 icount = i; 977 for (i = 0; i < icount; i++) 978 gs_destroy_candev(dev->canch[i]); 979 980 usb_kill_anchored_urbs(&dev->rx_submitted); 981 kfree(dev); 982 return rc; 983 } 984 dev->canch[i]->parent = dev; 985 } 986 987 return 0; 988 } 989 990 static void gs_usb_disconnect(struct usb_interface *intf) 991 { 992 unsigned i; 993 struct gs_usb *dev = usb_get_intfdata(intf); 994 usb_set_intfdata(intf, NULL); 995 996 if (!dev) { 997 dev_err(&intf->dev, "Disconnect (nodata)\n"); 998 return; 999 } 1000 1001 for (i = 0; i < GS_MAX_INTF; i++) 1002 if (dev->canch[i]) 1003 gs_destroy_candev(dev->canch[i]); 1004 1005 usb_kill_anchored_urbs(&dev->rx_submitted); 1006 kfree(dev); 1007 } 1008 1009 static const struct usb_device_id gs_usb_table[] = { 1010 { USB_DEVICE_INTERFACE_NUMBER(USB_GSUSB_1_VENDOR_ID, 1011 USB_GSUSB_1_PRODUCT_ID, 0) }, 1012 { USB_DEVICE_INTERFACE_NUMBER(USB_CANDLELIGHT_VENDOR_ID, 1013 USB_CANDLELIGHT_PRODUCT_ID, 0) }, 1014 {} /* Terminating entry */ 1015 }; 1016 1017 MODULE_DEVICE_TABLE(usb, gs_usb_table); 1018 1019 static struct usb_driver gs_usb_driver = { 1020 .name = "gs_usb", 1021 .probe = gs_usb_probe, 1022 .disconnect = gs_usb_disconnect, 1023 .id_table = gs_usb_table, 1024 }; 1025 1026 module_usb_driver(gs_usb_driver); 1027 1028 MODULE_AUTHOR("Maximilian Schneider <mws@schneidersoft.net>"); 1029 MODULE_DESCRIPTION( 1030 "Socket CAN device driver for Geschwister Schneider Technologie-, " 1031 "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces\n" 1032 "and bytewerk.org candleLight USB CAN interfaces."); 1033 MODULE_LICENSE("GPL v2"); 1034