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 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 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->can_dlc = 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 = bt->prop_seg; 428 dbt->phase_seg1 = bt->phase_seg1; 429 dbt->phase_seg2 = bt->phase_seg2; 430 dbt->sjw = bt->sjw; 431 dbt->brp = 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; 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 %d\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 atomic_dec(&dev->active_tx_urbs); 468 469 if (!netif_device_present(netdev)) 470 return; 471 472 if (netif_queue_stopped(netdev)) 473 netif_wake_queue(netdev); 474 } 475 476 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb, 477 struct net_device *netdev) 478 { 479 struct gs_can *dev = netdev_priv(netdev); 480 struct net_device_stats *stats = &dev->netdev->stats; 481 struct urb *urb; 482 struct gs_host_frame *hf; 483 struct can_frame *cf; 484 int rc; 485 unsigned int idx; 486 struct gs_tx_context *txc; 487 488 if (can_dropped_invalid_skb(netdev, skb)) 489 return NETDEV_TX_OK; 490 491 /* find an empty context to keep track of transmission */ 492 txc = gs_alloc_tx_context(dev); 493 if (!txc) 494 return NETDEV_TX_BUSY; 495 496 /* create a URB, and a buffer for it */ 497 urb = usb_alloc_urb(0, GFP_ATOMIC); 498 if (!urb) 499 goto nomem_urb; 500 501 hf = usb_alloc_coherent(dev->udev, sizeof(*hf), GFP_ATOMIC, 502 &urb->transfer_dma); 503 if (!hf) { 504 netdev_err(netdev, "No memory left for USB buffer\n"); 505 goto nomem_hf; 506 } 507 508 idx = txc->echo_id; 509 510 if (idx >= GS_MAX_TX_URBS) { 511 netdev_err(netdev, "Invalid tx context %d\n", idx); 512 goto badidx; 513 } 514 515 hf->echo_id = idx; 516 hf->channel = dev->channel; 517 518 cf = (struct can_frame *)skb->data; 519 520 hf->can_id = cf->can_id; 521 hf->can_dlc = cf->can_dlc; 522 memcpy(hf->data, cf->data, cf->can_dlc); 523 524 usb_fill_bulk_urb(urb, dev->udev, 525 usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT), 526 hf, 527 sizeof(*hf), 528 gs_usb_xmit_callback, 529 txc); 530 531 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 532 usb_anchor_urb(urb, &dev->tx_submitted); 533 534 can_put_echo_skb(skb, netdev, idx); 535 536 atomic_inc(&dev->active_tx_urbs); 537 538 rc = usb_submit_urb(urb, GFP_ATOMIC); 539 if (unlikely(rc)) { /* usb send failed */ 540 atomic_dec(&dev->active_tx_urbs); 541 542 can_free_echo_skb(netdev, idx); 543 gs_free_tx_context(txc); 544 545 usb_unanchor_urb(urb); 546 usb_free_coherent(dev->udev, 547 sizeof(*hf), 548 hf, 549 urb->transfer_dma); 550 551 if (rc == -ENODEV) { 552 netif_device_detach(netdev); 553 } else { 554 netdev_err(netdev, "usb_submit failed (err=%d)\n", rc); 555 stats->tx_dropped++; 556 } 557 } else { 558 /* Slow down tx path */ 559 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS) 560 netif_stop_queue(netdev); 561 } 562 563 /* let usb core take care of this urb */ 564 usb_free_urb(urb); 565 566 return NETDEV_TX_OK; 567 568 badidx: 569 usb_free_coherent(dev->udev, 570 sizeof(*hf), 571 hf, 572 urb->transfer_dma); 573 nomem_hf: 574 usb_free_urb(urb); 575 576 nomem_urb: 577 gs_free_tx_context(txc); 578 dev_kfree_skb(skb); 579 stats->tx_dropped++; 580 return NETDEV_TX_OK; 581 } 582 583 static int gs_can_open(struct net_device *netdev) 584 { 585 struct gs_can *dev = netdev_priv(netdev); 586 struct gs_usb *parent = dev->parent; 587 int rc, i; 588 struct gs_device_mode *dm; 589 u32 ctrlmode; 590 591 rc = open_candev(netdev); 592 if (rc) 593 return rc; 594 595 if (atomic_add_return(1, &parent->active_channels) == 1) { 596 for (i = 0; i < GS_MAX_RX_URBS; i++) { 597 struct urb *urb; 598 u8 *buf; 599 600 /* alloc rx urb */ 601 urb = usb_alloc_urb(0, GFP_KERNEL); 602 if (!urb) 603 return -ENOMEM; 604 605 /* alloc rx buffer */ 606 buf = usb_alloc_coherent(dev->udev, 607 sizeof(struct gs_host_frame), 608 GFP_KERNEL, 609 &urb->transfer_dma); 610 if (!buf) { 611 netdev_err(netdev, 612 "No memory left for USB buffer\n"); 613 usb_free_urb(urb); 614 return -ENOMEM; 615 } 616 617 /* fill, anchor, and submit rx urb */ 618 usb_fill_bulk_urb(urb, 619 dev->udev, 620 usb_rcvbulkpipe(dev->udev, 621 GSUSB_ENDPOINT_IN), 622 buf, 623 sizeof(struct gs_host_frame), 624 gs_usb_receive_bulk_callback, 625 parent); 626 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 627 628 usb_anchor_urb(urb, &parent->rx_submitted); 629 630 rc = usb_submit_urb(urb, GFP_KERNEL); 631 if (rc) { 632 if (rc == -ENODEV) 633 netif_device_detach(dev->netdev); 634 635 netdev_err(netdev, 636 "usb_submit failed (err=%d)\n", 637 rc); 638 639 usb_unanchor_urb(urb); 640 break; 641 } 642 643 /* Drop reference, 644 * USB core will take care of freeing it 645 */ 646 usb_free_urb(urb); 647 } 648 } 649 650 dm = kmalloc(sizeof(*dm), GFP_KERNEL); 651 if (!dm) 652 return -ENOMEM; 653 654 /* flags */ 655 ctrlmode = dev->can.ctrlmode; 656 dm->flags = 0; 657 658 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 659 dm->flags |= GS_CAN_MODE_LOOP_BACK; 660 else if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 661 dm->flags |= GS_CAN_MODE_LISTEN_ONLY; 662 663 /* Controller is not allowed to retry TX 664 * this mode is unavailable on atmels uc3c hardware 665 */ 666 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) 667 dm->flags |= GS_CAN_MODE_ONE_SHOT; 668 669 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES) 670 dm->flags |= GS_CAN_MODE_TRIPLE_SAMPLE; 671 672 /* finally start device */ 673 dm->mode = GS_CAN_MODE_START; 674 rc = usb_control_msg(interface_to_usbdev(dev->iface), 675 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 0), 676 GS_USB_BREQ_MODE, 677 USB_DIR_OUT | USB_TYPE_VENDOR | 678 USB_RECIP_INTERFACE, 679 dev->channel, 680 0, 681 dm, 682 sizeof(*dm), 683 1000); 684 685 if (rc < 0) { 686 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc); 687 kfree(dm); 688 return rc; 689 } 690 691 kfree(dm); 692 693 dev->can.state = CAN_STATE_ERROR_ACTIVE; 694 695 if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)) 696 netif_start_queue(netdev); 697 698 return 0; 699 } 700 701 static int gs_can_close(struct net_device *netdev) 702 { 703 int rc; 704 struct gs_can *dev = netdev_priv(netdev); 705 struct gs_usb *parent = dev->parent; 706 707 netif_stop_queue(netdev); 708 709 /* Stop polling */ 710 if (atomic_dec_and_test(&parent->active_channels)) 711 usb_kill_anchored_urbs(&parent->rx_submitted); 712 713 /* Stop sending URBs */ 714 usb_kill_anchored_urbs(&dev->tx_submitted); 715 atomic_set(&dev->active_tx_urbs, 0); 716 717 /* reset the device */ 718 rc = gs_cmd_reset(parent, dev); 719 if (rc < 0) 720 netdev_warn(netdev, "Couldn't shutdown device (err=%d)", rc); 721 722 /* reset tx contexts */ 723 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 724 dev->tx_context[rc].dev = dev; 725 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 726 } 727 728 /* close the netdev */ 729 close_candev(netdev); 730 731 return 0; 732 } 733 734 static const struct net_device_ops gs_usb_netdev_ops = { 735 .ndo_open = gs_can_open, 736 .ndo_stop = gs_can_close, 737 .ndo_start_xmit = gs_can_start_xmit, 738 .ndo_change_mtu = can_change_mtu, 739 }; 740 741 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify) 742 { 743 struct gs_can *dev = netdev_priv(netdev); 744 struct gs_identify_mode *imode; 745 int rc; 746 747 imode = kmalloc(sizeof(*imode), GFP_KERNEL); 748 749 if (!imode) 750 return -ENOMEM; 751 752 if (do_identify) 753 imode->mode = GS_CAN_IDENTIFY_ON; 754 else 755 imode->mode = GS_CAN_IDENTIFY_OFF; 756 757 rc = usb_control_msg(interface_to_usbdev(dev->iface), 758 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 759 0), 760 GS_USB_BREQ_IDENTIFY, 761 USB_DIR_OUT | USB_TYPE_VENDOR | 762 USB_RECIP_INTERFACE, 763 dev->channel, 764 0, 765 imode, 766 sizeof(*imode), 767 100); 768 769 kfree(imode); 770 771 return (rc > 0) ? 0 : rc; 772 } 773 774 /* blink LED's for finding the this interface */ 775 static int gs_usb_set_phys_id(struct net_device *dev, 776 enum ethtool_phys_id_state state) 777 { 778 int rc = 0; 779 780 switch (state) { 781 case ETHTOOL_ID_ACTIVE: 782 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_ON); 783 break; 784 case ETHTOOL_ID_INACTIVE: 785 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_OFF); 786 break; 787 default: 788 break; 789 } 790 791 return rc; 792 } 793 794 static const struct ethtool_ops gs_usb_ethtool_ops = { 795 .set_phys_id = gs_usb_set_phys_id, 796 }; 797 798 static struct gs_can *gs_make_candev(unsigned int channel, 799 struct usb_interface *intf, 800 struct gs_device_config *dconf) 801 { 802 struct gs_can *dev; 803 struct net_device *netdev; 804 int rc; 805 struct gs_device_bt_const *bt_const; 806 807 bt_const = kmalloc(sizeof(*bt_const), GFP_KERNEL); 808 if (!bt_const) 809 return ERR_PTR(-ENOMEM); 810 811 /* fetch bit timing constants */ 812 rc = usb_control_msg(interface_to_usbdev(intf), 813 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 814 GS_USB_BREQ_BT_CONST, 815 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 816 channel, 817 0, 818 bt_const, 819 sizeof(*bt_const), 820 1000); 821 822 if (rc < 0) { 823 dev_err(&intf->dev, 824 "Couldn't get bit timing const for channel (err=%d)\n", 825 rc); 826 kfree(bt_const); 827 return ERR_PTR(rc); 828 } 829 830 /* create netdev */ 831 netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS); 832 if (!netdev) { 833 dev_err(&intf->dev, "Couldn't allocate candev\n"); 834 kfree(bt_const); 835 return ERR_PTR(-ENOMEM); 836 } 837 838 dev = netdev_priv(netdev); 839 840 netdev->netdev_ops = &gs_usb_netdev_ops; 841 842 netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */ 843 844 /* dev settup */ 845 strcpy(dev->bt_const.name, "gs_usb"); 846 dev->bt_const.tseg1_min = bt_const->tseg1_min; 847 dev->bt_const.tseg1_max = bt_const->tseg1_max; 848 dev->bt_const.tseg2_min = bt_const->tseg2_min; 849 dev->bt_const.tseg2_max = bt_const->tseg2_max; 850 dev->bt_const.sjw_max = bt_const->sjw_max; 851 dev->bt_const.brp_min = bt_const->brp_min; 852 dev->bt_const.brp_max = bt_const->brp_max; 853 dev->bt_const.brp_inc = bt_const->brp_inc; 854 855 dev->udev = interface_to_usbdev(intf); 856 dev->iface = intf; 857 dev->netdev = netdev; 858 dev->channel = channel; 859 860 init_usb_anchor(&dev->tx_submitted); 861 atomic_set(&dev->active_tx_urbs, 0); 862 spin_lock_init(&dev->tx_ctx_lock); 863 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 864 dev->tx_context[rc].dev = dev; 865 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 866 } 867 868 /* can settup */ 869 dev->can.state = CAN_STATE_STOPPED; 870 dev->can.clock.freq = bt_const->fclk_can; 871 dev->can.bittiming_const = &dev->bt_const; 872 dev->can.do_set_bittiming = gs_usb_set_bittiming; 873 874 dev->can.ctrlmode_supported = 0; 875 876 if (bt_const->feature & GS_CAN_FEATURE_LISTEN_ONLY) 877 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY; 878 879 if (bt_const->feature & GS_CAN_FEATURE_LOOP_BACK) 880 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK; 881 882 if (bt_const->feature & GS_CAN_FEATURE_TRIPLE_SAMPLE) 883 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; 884 885 if (bt_const->feature & GS_CAN_FEATURE_ONE_SHOT) 886 dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT; 887 888 SET_NETDEV_DEV(netdev, &intf->dev); 889 890 if (dconf->sw_version > 1) 891 if (bt_const->feature & GS_CAN_FEATURE_IDENTIFY) 892 netdev->ethtool_ops = &gs_usb_ethtool_ops; 893 894 kfree(bt_const); 895 896 rc = register_candev(dev->netdev); 897 if (rc) { 898 free_candev(dev->netdev); 899 dev_err(&intf->dev, "Couldn't register candev (err=%d)\n", rc); 900 return ERR_PTR(rc); 901 } 902 903 return dev; 904 } 905 906 static void gs_destroy_candev(struct gs_can *dev) 907 { 908 unregister_candev(dev->netdev); 909 usb_kill_anchored_urbs(&dev->tx_submitted); 910 free_candev(dev->netdev); 911 } 912 913 static int gs_usb_probe(struct usb_interface *intf, 914 const struct usb_device_id *id) 915 { 916 struct gs_usb *dev; 917 int rc = -ENOMEM; 918 unsigned int icount, i; 919 struct gs_host_config *hconf; 920 struct gs_device_config *dconf; 921 922 hconf = kmalloc(sizeof(*hconf), GFP_KERNEL); 923 if (!hconf) 924 return -ENOMEM; 925 926 hconf->byte_order = 0x0000beef; 927 928 /* send host config */ 929 rc = usb_control_msg(interface_to_usbdev(intf), 930 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 931 GS_USB_BREQ_HOST_FORMAT, 932 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 933 1, 934 intf->altsetting[0].desc.bInterfaceNumber, 935 hconf, 936 sizeof(*hconf), 937 1000); 938 939 kfree(hconf); 940 941 if (rc < 0) { 942 dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", 943 rc); 944 return rc; 945 } 946 947 dconf = kmalloc(sizeof(*dconf), GFP_KERNEL); 948 if (!dconf) 949 return -ENOMEM; 950 951 /* read device config */ 952 rc = usb_control_msg(interface_to_usbdev(intf), 953 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 954 GS_USB_BREQ_DEVICE_CONFIG, 955 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 956 1, 957 intf->altsetting[0].desc.bInterfaceNumber, 958 dconf, 959 sizeof(*dconf), 960 1000); 961 if (rc < 0) { 962 dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n", 963 rc); 964 kfree(dconf); 965 return rc; 966 } 967 968 icount = dconf->icount + 1; 969 dev_info(&intf->dev, "Configuring for %d interfaces\n", icount); 970 971 if (icount > GS_MAX_INTF) { 972 dev_err(&intf->dev, 973 "Driver cannot handle more that %d CAN interfaces\n", 974 GS_MAX_INTF); 975 kfree(dconf); 976 return -EINVAL; 977 } 978 979 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 980 if (!dev) { 981 kfree(dconf); 982 return -ENOMEM; 983 } 984 985 init_usb_anchor(&dev->rx_submitted); 986 987 atomic_set(&dev->active_channels, 0); 988 989 usb_set_intfdata(intf, dev); 990 dev->udev = interface_to_usbdev(intf); 991 992 for (i = 0; i < icount; i++) { 993 dev->canch[i] = gs_make_candev(i, intf, dconf); 994 if (IS_ERR_OR_NULL(dev->canch[i])) { 995 /* save error code to return later */ 996 rc = PTR_ERR(dev->canch[i]); 997 998 /* on failure destroy previously created candevs */ 999 icount = i; 1000 for (i = 0; i < icount; i++) 1001 gs_destroy_candev(dev->canch[i]); 1002 1003 usb_kill_anchored_urbs(&dev->rx_submitted); 1004 kfree(dconf); 1005 kfree(dev); 1006 return rc; 1007 } 1008 dev->canch[i]->parent = dev; 1009 } 1010 1011 kfree(dconf); 1012 1013 return 0; 1014 } 1015 1016 static void gs_usb_disconnect(struct usb_interface *intf) 1017 { 1018 unsigned i; 1019 struct gs_usb *dev = usb_get_intfdata(intf); 1020 usb_set_intfdata(intf, NULL); 1021 1022 if (!dev) { 1023 dev_err(&intf->dev, "Disconnect (nodata)\n"); 1024 return; 1025 } 1026 1027 for (i = 0; i < GS_MAX_INTF; i++) 1028 if (dev->canch[i]) 1029 gs_destroy_candev(dev->canch[i]); 1030 1031 usb_kill_anchored_urbs(&dev->rx_submitted); 1032 kfree(dev); 1033 } 1034 1035 static const struct usb_device_id gs_usb_table[] = { 1036 { USB_DEVICE_INTERFACE_NUMBER(USB_GSUSB_1_VENDOR_ID, 1037 USB_GSUSB_1_PRODUCT_ID, 0) }, 1038 { USB_DEVICE_INTERFACE_NUMBER(USB_CANDLELIGHT_VENDOR_ID, 1039 USB_CANDLELIGHT_PRODUCT_ID, 0) }, 1040 {} /* Terminating entry */ 1041 }; 1042 1043 MODULE_DEVICE_TABLE(usb, gs_usb_table); 1044 1045 static struct usb_driver gs_usb_driver = { 1046 .name = "gs_usb", 1047 .probe = gs_usb_probe, 1048 .disconnect = gs_usb_disconnect, 1049 .id_table = gs_usb_table, 1050 }; 1051 1052 module_usb_driver(gs_usb_driver); 1053 1054 MODULE_AUTHOR("Maximilian Schneider <mws@schneidersoft.net>"); 1055 MODULE_DESCRIPTION( 1056 "Socket CAN device driver for Geschwister Schneider Technologie-, " 1057 "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces\n" 1058 "and bytewerk.org candleLight USB CAN interfaces."); 1059 MODULE_LICENSE("GPL v2"); 1060