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_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 kfree(dm); 269 270 return rc; 271 } 272 273 static void gs_update_state(struct gs_can *dev, struct can_frame *cf) 274 { 275 struct can_device_stats *can_stats = &dev->can.can_stats; 276 277 if (cf->can_id & CAN_ERR_RESTARTED) { 278 dev->can.state = CAN_STATE_ERROR_ACTIVE; 279 can_stats->restarts++; 280 } else if (cf->can_id & CAN_ERR_BUSOFF) { 281 dev->can.state = CAN_STATE_BUS_OFF; 282 can_stats->bus_off++; 283 } else if (cf->can_id & CAN_ERR_CRTL) { 284 if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) || 285 (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) { 286 dev->can.state = CAN_STATE_ERROR_WARNING; 287 can_stats->error_warning++; 288 } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) || 289 (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) { 290 dev->can.state = CAN_STATE_ERROR_PASSIVE; 291 can_stats->error_passive++; 292 } else { 293 dev->can.state = CAN_STATE_ERROR_ACTIVE; 294 } 295 } 296 } 297 298 static void gs_usb_receive_bulk_callback(struct urb *urb) 299 { 300 struct gs_usb *usbcan = urb->context; 301 struct gs_can *dev; 302 struct net_device *netdev; 303 int rc; 304 struct net_device_stats *stats; 305 struct gs_host_frame *hf = urb->transfer_buffer; 306 struct gs_tx_context *txc; 307 struct can_frame *cf; 308 struct sk_buff *skb; 309 310 BUG_ON(!usbcan); 311 312 switch (urb->status) { 313 case 0: /* success */ 314 break; 315 case -ENOENT: 316 case -ESHUTDOWN: 317 return; 318 default: 319 /* do not resubmit aborted urbs. eg: when device goes down */ 320 return; 321 } 322 323 /* device reports out of range channel id */ 324 if (hf->channel >= GS_MAX_INTF) 325 goto resubmit_urb; 326 327 dev = usbcan->canch[hf->channel]; 328 329 netdev = dev->netdev; 330 stats = &netdev->stats; 331 332 if (!netif_device_present(netdev)) 333 return; 334 335 if (hf->echo_id == -1) { /* normal rx */ 336 skb = alloc_can_skb(dev->netdev, &cf); 337 if (!skb) 338 return; 339 340 cf->can_id = hf->can_id; 341 342 cf->can_dlc = get_can_dlc(hf->can_dlc); 343 memcpy(cf->data, hf->data, 8); 344 345 /* ERROR frames tell us information about the controller */ 346 if (hf->can_id & CAN_ERR_FLAG) 347 gs_update_state(dev, cf); 348 349 netdev->stats.rx_packets++; 350 netdev->stats.rx_bytes += hf->can_dlc; 351 352 netif_rx(skb); 353 } else { /* echo_id == hf->echo_id */ 354 if (hf->echo_id >= GS_MAX_TX_URBS) { 355 netdev_err(netdev, 356 "Unexpected out of range echo id %d\n", 357 hf->echo_id); 358 goto resubmit_urb; 359 } 360 361 netdev->stats.tx_packets++; 362 netdev->stats.tx_bytes += hf->can_dlc; 363 364 txc = gs_get_tx_context(dev, hf->echo_id); 365 366 /* bad devices send bad echo_ids. */ 367 if (!txc) { 368 netdev_err(netdev, 369 "Unexpected unused echo id %d\n", 370 hf->echo_id); 371 goto resubmit_urb; 372 } 373 374 can_get_echo_skb(netdev, hf->echo_id); 375 376 gs_free_tx_context(txc); 377 378 atomic_dec(&dev->active_tx_urbs); 379 380 netif_wake_queue(netdev); 381 } 382 383 if (hf->flags & GS_CAN_FLAG_OVERFLOW) { 384 skb = alloc_can_err_skb(netdev, &cf); 385 if (!skb) 386 goto resubmit_urb; 387 388 cf->can_id |= CAN_ERR_CRTL; 389 cf->can_dlc = CAN_ERR_DLC; 390 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 391 stats->rx_over_errors++; 392 stats->rx_errors++; 393 netif_rx(skb); 394 } 395 396 resubmit_urb: 397 usb_fill_bulk_urb(urb, 398 usbcan->udev, 399 usb_rcvbulkpipe(usbcan->udev, GSUSB_ENDPOINT_IN), 400 hf, 401 sizeof(struct gs_host_frame), 402 gs_usb_receive_bulk_callback, 403 usbcan 404 ); 405 406 rc = usb_submit_urb(urb, GFP_ATOMIC); 407 408 /* USB failure take down all interfaces */ 409 if (rc == -ENODEV) { 410 for (rc = 0; rc < GS_MAX_INTF; rc++) { 411 if (usbcan->canch[rc]) 412 netif_device_detach(usbcan->canch[rc]->netdev); 413 } 414 } 415 } 416 417 static int gs_usb_set_bittiming(struct net_device *netdev) 418 { 419 struct gs_can *dev = netdev_priv(netdev); 420 struct can_bittiming *bt = &dev->can.bittiming; 421 struct usb_interface *intf = dev->iface; 422 int rc; 423 struct gs_device_bittiming *dbt; 424 425 dbt = kmalloc(sizeof(*dbt), GFP_KERNEL); 426 if (!dbt) 427 return -ENOMEM; 428 429 dbt->prop_seg = bt->prop_seg; 430 dbt->phase_seg1 = bt->phase_seg1; 431 dbt->phase_seg2 = bt->phase_seg2; 432 dbt->sjw = bt->sjw; 433 dbt->brp = bt->brp; 434 435 /* request bit timings */ 436 rc = usb_control_msg(interface_to_usbdev(intf), 437 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 438 GS_USB_BREQ_BITTIMING, 439 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 440 dev->channel, 441 0, 442 dbt, 443 sizeof(*dbt), 444 1000); 445 446 kfree(dbt); 447 448 if (rc < 0) 449 dev_err(netdev->dev.parent, "Couldn't set bittimings (err=%d)", 450 rc); 451 452 return (rc > 0) ? 0 : rc; 453 } 454 455 static void gs_usb_xmit_callback(struct urb *urb) 456 { 457 struct gs_tx_context *txc = urb->context; 458 struct gs_can *dev = txc->dev; 459 struct net_device *netdev = dev->netdev; 460 461 if (urb->status) 462 netdev_info(netdev, "usb xmit fail %d\n", txc->echo_id); 463 464 usb_free_coherent(urb->dev, 465 urb->transfer_buffer_length, 466 urb->transfer_buffer, 467 urb->transfer_dma); 468 } 469 470 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb, 471 struct net_device *netdev) 472 { 473 struct gs_can *dev = netdev_priv(netdev); 474 struct net_device_stats *stats = &dev->netdev->stats; 475 struct urb *urb; 476 struct gs_host_frame *hf; 477 struct can_frame *cf; 478 int rc; 479 unsigned int idx; 480 struct gs_tx_context *txc; 481 482 if (can_dropped_invalid_skb(netdev, skb)) 483 return NETDEV_TX_OK; 484 485 /* find an empty context to keep track of transmission */ 486 txc = gs_alloc_tx_context(dev); 487 if (!txc) 488 return NETDEV_TX_BUSY; 489 490 /* create a URB, and a buffer for it */ 491 urb = usb_alloc_urb(0, GFP_ATOMIC); 492 if (!urb) 493 goto nomem_urb; 494 495 hf = usb_alloc_coherent(dev->udev, sizeof(*hf), GFP_ATOMIC, 496 &urb->transfer_dma); 497 if (!hf) { 498 netdev_err(netdev, "No memory left for USB buffer\n"); 499 goto nomem_hf; 500 } 501 502 idx = txc->echo_id; 503 504 if (idx >= GS_MAX_TX_URBS) { 505 netdev_err(netdev, "Invalid tx context %d\n", idx); 506 goto badidx; 507 } 508 509 hf->echo_id = idx; 510 hf->channel = dev->channel; 511 512 cf = (struct can_frame *)skb->data; 513 514 hf->can_id = cf->can_id; 515 hf->can_dlc = cf->can_dlc; 516 memcpy(hf->data, cf->data, cf->can_dlc); 517 518 usb_fill_bulk_urb(urb, dev->udev, 519 usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT), 520 hf, 521 sizeof(*hf), 522 gs_usb_xmit_callback, 523 txc); 524 525 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 526 usb_anchor_urb(urb, &dev->tx_submitted); 527 528 can_put_echo_skb(skb, netdev, idx); 529 530 atomic_inc(&dev->active_tx_urbs); 531 532 rc = usb_submit_urb(urb, GFP_ATOMIC); 533 if (unlikely(rc)) { /* usb send failed */ 534 atomic_dec(&dev->active_tx_urbs); 535 536 can_free_echo_skb(netdev, idx); 537 gs_free_tx_context(txc); 538 539 usb_unanchor_urb(urb); 540 usb_free_coherent(dev->udev, 541 sizeof(*hf), 542 hf, 543 urb->transfer_dma); 544 545 if (rc == -ENODEV) { 546 netif_device_detach(netdev); 547 } else { 548 netdev_err(netdev, "usb_submit failed (err=%d)\n", rc); 549 stats->tx_dropped++; 550 } 551 } else { 552 /* Slow down tx path */ 553 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS) 554 netif_stop_queue(netdev); 555 } 556 557 /* let usb core take care of this urb */ 558 usb_free_urb(urb); 559 560 return NETDEV_TX_OK; 561 562 badidx: 563 usb_free_coherent(dev->udev, 564 sizeof(*hf), 565 hf, 566 urb->transfer_dma); 567 nomem_hf: 568 usb_free_urb(urb); 569 570 nomem_urb: 571 gs_free_tx_context(txc); 572 dev_kfree_skb(skb); 573 stats->tx_dropped++; 574 return NETDEV_TX_OK; 575 } 576 577 static int gs_can_open(struct net_device *netdev) 578 { 579 struct gs_can *dev = netdev_priv(netdev); 580 struct gs_usb *parent = dev->parent; 581 int rc, i; 582 struct gs_device_mode *dm; 583 u32 ctrlmode; 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 break; 635 } 636 637 /* Drop reference, 638 * USB core will take care of freeing it 639 */ 640 usb_free_urb(urb); 641 } 642 } 643 644 dm = kmalloc(sizeof(*dm), GFP_KERNEL); 645 if (!dm) 646 return -ENOMEM; 647 648 /* flags */ 649 ctrlmode = dev->can.ctrlmode; 650 dm->flags = 0; 651 652 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 653 dm->flags |= GS_CAN_MODE_LOOP_BACK; 654 else if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 655 dm->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 dm->flags |= GS_CAN_MODE_ONE_SHOT; 662 663 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES) 664 dm->flags |= GS_CAN_MODE_TRIPLE_SAMPLE; 665 666 /* finally start device */ 667 dm->mode = GS_CAN_MODE_START; 668 rc = usb_control_msg(interface_to_usbdev(dev->iface), 669 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 0), 670 GS_USB_BREQ_MODE, 671 USB_DIR_OUT | USB_TYPE_VENDOR | 672 USB_RECIP_INTERFACE, 673 dev->channel, 674 0, 675 dm, 676 sizeof(*dm), 677 1000); 678 679 if (rc < 0) { 680 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc); 681 kfree(dm); 682 return rc; 683 } 684 685 kfree(dm); 686 687 dev->can.state = CAN_STATE_ERROR_ACTIVE; 688 689 if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)) 690 netif_start_queue(netdev); 691 692 return 0; 693 } 694 695 static int gs_can_close(struct net_device *netdev) 696 { 697 int rc; 698 struct gs_can *dev = netdev_priv(netdev); 699 struct gs_usb *parent = dev->parent; 700 701 netif_stop_queue(netdev); 702 703 /* Stop polling */ 704 if (atomic_dec_and_test(&parent->active_channels)) 705 usb_kill_anchored_urbs(&parent->rx_submitted); 706 707 /* Stop sending URBs */ 708 usb_kill_anchored_urbs(&dev->tx_submitted); 709 atomic_set(&dev->active_tx_urbs, 0); 710 711 /* reset the device */ 712 rc = gs_cmd_reset(dev); 713 if (rc < 0) 714 netdev_warn(netdev, "Couldn't shutdown device (err=%d)", rc); 715 716 /* reset tx contexts */ 717 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 718 dev->tx_context[rc].dev = dev; 719 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 720 } 721 722 /* close the netdev */ 723 close_candev(netdev); 724 725 return 0; 726 } 727 728 static const struct net_device_ops gs_usb_netdev_ops = { 729 .ndo_open = gs_can_open, 730 .ndo_stop = gs_can_close, 731 .ndo_start_xmit = gs_can_start_xmit, 732 .ndo_change_mtu = can_change_mtu, 733 }; 734 735 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify) 736 { 737 struct gs_can *dev = netdev_priv(netdev); 738 struct gs_identify_mode *imode; 739 int rc; 740 741 imode = kmalloc(sizeof(*imode), GFP_KERNEL); 742 743 if (!imode) 744 return -ENOMEM; 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 kfree(imode); 764 765 return (rc > 0) ? 0 : rc; 766 } 767 768 /* blink LED's for finding the this interface */ 769 static int gs_usb_set_phys_id(struct net_device *dev, 770 enum ethtool_phys_id_state state) 771 { 772 int rc = 0; 773 774 switch (state) { 775 case ETHTOOL_ID_ACTIVE: 776 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_ON); 777 break; 778 case ETHTOOL_ID_INACTIVE: 779 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_OFF); 780 break; 781 default: 782 break; 783 } 784 785 return rc; 786 } 787 788 static const struct ethtool_ops gs_usb_ethtool_ops = { 789 .set_phys_id = gs_usb_set_phys_id, 790 }; 791 792 static struct gs_can *gs_make_candev(unsigned int channel, 793 struct usb_interface *intf, 794 struct gs_device_config *dconf) 795 { 796 struct gs_can *dev; 797 struct net_device *netdev; 798 int rc; 799 struct gs_device_bt_const *bt_const; 800 801 bt_const = kmalloc(sizeof(*bt_const), GFP_KERNEL); 802 if (!bt_const) 803 return ERR_PTR(-ENOMEM); 804 805 /* fetch bit timing constants */ 806 rc = usb_control_msg(interface_to_usbdev(intf), 807 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 808 GS_USB_BREQ_BT_CONST, 809 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 810 channel, 811 0, 812 bt_const, 813 sizeof(*bt_const), 814 1000); 815 816 if (rc < 0) { 817 dev_err(&intf->dev, 818 "Couldn't get bit timing const for channel (err=%d)\n", 819 rc); 820 kfree(bt_const); 821 return ERR_PTR(rc); 822 } 823 824 /* create netdev */ 825 netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS); 826 if (!netdev) { 827 dev_err(&intf->dev, "Couldn't allocate candev\n"); 828 kfree(bt_const); 829 return ERR_PTR(-ENOMEM); 830 } 831 832 dev = netdev_priv(netdev); 833 834 netdev->netdev_ops = &gs_usb_netdev_ops; 835 836 netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */ 837 838 /* dev settup */ 839 strcpy(dev->bt_const.name, "gs_usb"); 840 dev->bt_const.tseg1_min = bt_const->tseg1_min; 841 dev->bt_const.tseg1_max = bt_const->tseg1_max; 842 dev->bt_const.tseg2_min = bt_const->tseg2_min; 843 dev->bt_const.tseg2_max = bt_const->tseg2_max; 844 dev->bt_const.sjw_max = bt_const->sjw_max; 845 dev->bt_const.brp_min = bt_const->brp_min; 846 dev->bt_const.brp_max = bt_const->brp_max; 847 dev->bt_const.brp_inc = bt_const->brp_inc; 848 849 dev->udev = interface_to_usbdev(intf); 850 dev->iface = intf; 851 dev->netdev = netdev; 852 dev->channel = channel; 853 854 init_usb_anchor(&dev->tx_submitted); 855 atomic_set(&dev->active_tx_urbs, 0); 856 spin_lock_init(&dev->tx_ctx_lock); 857 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 858 dev->tx_context[rc].dev = dev; 859 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 860 } 861 862 /* can settup */ 863 dev->can.state = CAN_STATE_STOPPED; 864 dev->can.clock.freq = bt_const->fclk_can; 865 dev->can.bittiming_const = &dev->bt_const; 866 dev->can.do_set_bittiming = gs_usb_set_bittiming; 867 868 dev->can.ctrlmode_supported = 0; 869 870 if (bt_const->feature & GS_CAN_FEATURE_LISTEN_ONLY) 871 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY; 872 873 if (bt_const->feature & GS_CAN_FEATURE_LOOP_BACK) 874 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK; 875 876 if (bt_const->feature & GS_CAN_FEATURE_TRIPLE_SAMPLE) 877 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; 878 879 if (bt_const->feature & GS_CAN_FEATURE_ONE_SHOT) 880 dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT; 881 882 SET_NETDEV_DEV(netdev, &intf->dev); 883 884 if (dconf->sw_version > 1) 885 if (bt_const->feature & GS_CAN_FEATURE_IDENTIFY) 886 netdev->ethtool_ops = &gs_usb_ethtool_ops; 887 888 kfree(bt_const); 889 890 rc = register_candev(dev->netdev); 891 if (rc) { 892 free_candev(dev->netdev); 893 dev_err(&intf->dev, "Couldn't register candev (err=%d)\n", rc); 894 return ERR_PTR(rc); 895 } 896 897 return dev; 898 } 899 900 static void gs_destroy_candev(struct gs_can *dev) 901 { 902 unregister_candev(dev->netdev); 903 usb_kill_anchored_urbs(&dev->tx_submitted); 904 free_candev(dev->netdev); 905 } 906 907 static int gs_usb_probe(struct usb_interface *intf, 908 const struct usb_device_id *id) 909 { 910 struct gs_usb *dev; 911 int rc = -ENOMEM; 912 unsigned int icount, i; 913 struct gs_host_config *hconf; 914 struct gs_device_config *dconf; 915 916 hconf = kmalloc(sizeof(*hconf), GFP_KERNEL); 917 if (!hconf) 918 return -ENOMEM; 919 920 hconf->byte_order = 0x0000beef; 921 922 /* send host config */ 923 rc = usb_control_msg(interface_to_usbdev(intf), 924 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 925 GS_USB_BREQ_HOST_FORMAT, 926 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 927 1, 928 intf->altsetting[0].desc.bInterfaceNumber, 929 hconf, 930 sizeof(*hconf), 931 1000); 932 933 kfree(hconf); 934 935 if (rc < 0) { 936 dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", 937 rc); 938 return rc; 939 } 940 941 dconf = kmalloc(sizeof(*dconf), GFP_KERNEL); 942 if (!dconf) 943 return -ENOMEM; 944 945 /* read device config */ 946 rc = usb_control_msg(interface_to_usbdev(intf), 947 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 948 GS_USB_BREQ_DEVICE_CONFIG, 949 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 950 1, 951 intf->altsetting[0].desc.bInterfaceNumber, 952 dconf, 953 sizeof(*dconf), 954 1000); 955 if (rc < 0) { 956 dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n", 957 rc); 958 kfree(dconf); 959 return rc; 960 } 961 962 icount = dconf->icount + 1; 963 dev_info(&intf->dev, "Configuring for %d interfaces\n", icount); 964 965 if (icount > GS_MAX_INTF) { 966 dev_err(&intf->dev, 967 "Driver cannot handle more that %d CAN interfaces\n", 968 GS_MAX_INTF); 969 kfree(dconf); 970 return -EINVAL; 971 } 972 973 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 974 if (!dev) { 975 kfree(dconf); 976 return -ENOMEM; 977 } 978 979 init_usb_anchor(&dev->rx_submitted); 980 981 atomic_set(&dev->active_channels, 0); 982 983 usb_set_intfdata(intf, dev); 984 dev->udev = interface_to_usbdev(intf); 985 986 for (i = 0; i < icount; i++) { 987 dev->canch[i] = gs_make_candev(i, intf, dconf); 988 if (IS_ERR_OR_NULL(dev->canch[i])) { 989 /* save error code to return later */ 990 rc = PTR_ERR(dev->canch[i]); 991 992 /* on failure destroy previously created candevs */ 993 icount = i; 994 for (i = 0; i < icount; i++) 995 gs_destroy_candev(dev->canch[i]); 996 997 usb_kill_anchored_urbs(&dev->rx_submitted); 998 kfree(dconf); 999 kfree(dev); 1000 return rc; 1001 } 1002 dev->canch[i]->parent = dev; 1003 } 1004 1005 kfree(dconf); 1006 1007 return 0; 1008 } 1009 1010 static void gs_usb_disconnect(struct usb_interface *intf) 1011 { 1012 unsigned i; 1013 struct gs_usb *dev = usb_get_intfdata(intf); 1014 usb_set_intfdata(intf, NULL); 1015 1016 if (!dev) { 1017 dev_err(&intf->dev, "Disconnect (nodata)\n"); 1018 return; 1019 } 1020 1021 for (i = 0; i < GS_MAX_INTF; i++) 1022 if (dev->canch[i]) 1023 gs_destroy_candev(dev->canch[i]); 1024 1025 usb_kill_anchored_urbs(&dev->rx_submitted); 1026 kfree(dev); 1027 } 1028 1029 static const struct usb_device_id gs_usb_table[] = { 1030 { USB_DEVICE_INTERFACE_NUMBER(USB_GSUSB_1_VENDOR_ID, 1031 USB_GSUSB_1_PRODUCT_ID, 0) }, 1032 { USB_DEVICE_INTERFACE_NUMBER(USB_CANDLELIGHT_VENDOR_ID, 1033 USB_CANDLELIGHT_PRODUCT_ID, 0) }, 1034 {} /* Terminating entry */ 1035 }; 1036 1037 MODULE_DEVICE_TABLE(usb, gs_usb_table); 1038 1039 static struct usb_driver gs_usb_driver = { 1040 .name = "gs_usb", 1041 .probe = gs_usb_probe, 1042 .disconnect = gs_usb_disconnect, 1043 .id_table = gs_usb_table, 1044 }; 1045 1046 module_usb_driver(gs_usb_driver); 1047 1048 MODULE_AUTHOR("Maximilian Schneider <mws@schneidersoft.net>"); 1049 MODULE_DESCRIPTION( 1050 "Socket CAN device driver for Geschwister Schneider Technologie-, " 1051 "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces\n" 1052 "and bytewerk.org candleLight USB CAN interfaces."); 1053 MODULE_LICENSE("GPL v2"); 1054