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