1 // SPDX-License-Identifier: GPL-2.0-only 2 /* CAN driver for Geschwister Schneider USB/CAN devices 3 * and bytewerk.org candleLight USB CAN interfaces. 4 * 5 * Copyright (C) 2013-2016 Geschwister Schneider Technologie-, 6 * Entwicklungs- und Vertriebs UG (Haftungsbeschränkt). 7 * Copyright (C) 2016 Hubert Denkmair 8 * 9 * Many thanks to all socketcan devs! 10 */ 11 12 #include <linux/ethtool.h> 13 #include <linux/init.h> 14 #include <linux/signal.h> 15 #include <linux/module.h> 16 #include <linux/netdevice.h> 17 #include <linux/usb.h> 18 19 #include <linux/can.h> 20 #include <linux/can/dev.h> 21 #include <linux/can/error.h> 22 23 /* Device specific constants */ 24 #define USB_GSUSB_1_VENDOR_ID 0x1d50 25 #define USB_GSUSB_1_PRODUCT_ID 0x606f 26 27 #define USB_CANDLELIGHT_VENDOR_ID 0x1209 28 #define USB_CANDLELIGHT_PRODUCT_ID 0x2323 29 30 #define GSUSB_ENDPOINT_IN 1 31 #define GSUSB_ENDPOINT_OUT 2 32 33 /* Device specific constants */ 34 enum gs_usb_breq { 35 GS_USB_BREQ_HOST_FORMAT = 0, 36 GS_USB_BREQ_BITTIMING, 37 GS_USB_BREQ_MODE, 38 GS_USB_BREQ_BERR, 39 GS_USB_BREQ_BT_CONST, 40 GS_USB_BREQ_DEVICE_CONFIG, 41 GS_USB_BREQ_TIMESTAMP, 42 GS_USB_BREQ_IDENTIFY, 43 }; 44 45 enum gs_can_mode { 46 /* reset a channel. turns it off */ 47 GS_CAN_MODE_RESET = 0, 48 /* starts a channel */ 49 GS_CAN_MODE_START 50 }; 51 52 enum gs_can_state { 53 GS_CAN_STATE_ERROR_ACTIVE = 0, 54 GS_CAN_STATE_ERROR_WARNING, 55 GS_CAN_STATE_ERROR_PASSIVE, 56 GS_CAN_STATE_BUS_OFF, 57 GS_CAN_STATE_STOPPED, 58 GS_CAN_STATE_SLEEPING 59 }; 60 61 enum gs_can_identify_mode { 62 GS_CAN_IDENTIFY_OFF = 0, 63 GS_CAN_IDENTIFY_ON 64 }; 65 66 /* data types passed between host and device */ 67 68 /* The firmware on the original USB2CAN by Geschwister Schneider 69 * Technologie Entwicklungs- und Vertriebs UG exchanges all data 70 * between the host and the device in host byte order. This is done 71 * with the struct gs_host_config::byte_order member, which is sent 72 * first to indicate the desired byte order. 73 * 74 * The widely used open source firmware candleLight doesn't support 75 * this feature and exchanges the data in little endian byte order. 76 */ 77 struct gs_host_config { 78 __le32 byte_order; 79 } __packed; 80 81 struct gs_device_config { 82 u8 reserved1; 83 u8 reserved2; 84 u8 reserved3; 85 u8 icount; 86 __le32 sw_version; 87 __le32 hw_version; 88 } __packed; 89 90 #define GS_CAN_MODE_NORMAL 0 91 #define GS_CAN_MODE_LISTEN_ONLY BIT(0) 92 #define GS_CAN_MODE_LOOP_BACK BIT(1) 93 #define GS_CAN_MODE_TRIPLE_SAMPLE BIT(2) 94 #define GS_CAN_MODE_ONE_SHOT BIT(3) 95 96 struct gs_device_mode { 97 __le32 mode; 98 __le32 flags; 99 } __packed; 100 101 struct gs_device_state { 102 __le32 state; 103 __le32 rxerr; 104 __le32 txerr; 105 } __packed; 106 107 struct gs_device_bittiming { 108 __le32 prop_seg; 109 __le32 phase_seg1; 110 __le32 phase_seg2; 111 __le32 sjw; 112 __le32 brp; 113 } __packed; 114 115 struct gs_identify_mode { 116 __le32 mode; 117 } __packed; 118 119 #define GS_CAN_FEATURE_LISTEN_ONLY BIT(0) 120 #define GS_CAN_FEATURE_LOOP_BACK BIT(1) 121 #define GS_CAN_FEATURE_TRIPLE_SAMPLE BIT(2) 122 #define GS_CAN_FEATURE_ONE_SHOT BIT(3) 123 #define GS_CAN_FEATURE_HW_TIMESTAMP BIT(4) 124 #define GS_CAN_FEATURE_IDENTIFY BIT(5) 125 126 struct gs_device_bt_const { 127 __le32 feature; 128 __le32 fclk_can; 129 __le32 tseg1_min; 130 __le32 tseg1_max; 131 __le32 tseg2_min; 132 __le32 tseg2_max; 133 __le32 sjw_max; 134 __le32 brp_min; 135 __le32 brp_max; 136 __le32 brp_inc; 137 } __packed; 138 139 #define GS_CAN_FLAG_OVERFLOW 1 140 141 struct gs_host_frame { 142 u32 echo_id; 143 __le32 can_id; 144 145 u8 can_dlc; 146 u8 channel; 147 u8 flags; 148 u8 reserved; 149 150 u8 data[8]; 151 } __packed; 152 /* The GS USB devices make use of the same flags and masks as in 153 * linux/can.h and linux/can/error.h, and no additional mapping is necessary. 154 */ 155 156 /* Only send a max of GS_MAX_TX_URBS frames per channel at a time. */ 157 #define GS_MAX_TX_URBS 10 158 /* Only launch a max of GS_MAX_RX_URBS usb requests at a time. */ 159 #define GS_MAX_RX_URBS 30 160 /* Maximum number of interfaces the driver supports per device. 161 * Current hardware only supports 2 interfaces. The future may vary. 162 */ 163 #define GS_MAX_INTF 2 164 165 struct gs_tx_context { 166 struct gs_can *dev; 167 unsigned int echo_id; 168 }; 169 170 struct gs_can { 171 struct can_priv can; /* must be the first member */ 172 173 struct gs_usb *parent; 174 175 struct net_device *netdev; 176 struct usb_device *udev; 177 struct usb_interface *iface; 178 179 struct can_bittiming_const bt_const; 180 unsigned int channel; /* channel number */ 181 182 /* This lock prevents a race condition between xmit and receive. */ 183 spinlock_t tx_ctx_lock; 184 struct gs_tx_context tx_context[GS_MAX_TX_URBS]; 185 186 struct usb_anchor tx_submitted; 187 atomic_t active_tx_urbs; 188 }; 189 190 /* usb interface struct */ 191 struct gs_usb { 192 struct gs_can *canch[GS_MAX_INTF]; 193 struct usb_anchor rx_submitted; 194 atomic_t active_channels; 195 struct usb_device *udev; 196 }; 197 198 /* 'allocate' a tx context. 199 * returns a valid tx context or NULL if there is no space. 200 */ 201 static struct gs_tx_context *gs_alloc_tx_context(struct gs_can *dev) 202 { 203 int i = 0; 204 unsigned long flags; 205 206 spin_lock_irqsave(&dev->tx_ctx_lock, flags); 207 208 for (; i < GS_MAX_TX_URBS; i++) { 209 if (dev->tx_context[i].echo_id == GS_MAX_TX_URBS) { 210 dev->tx_context[i].echo_id = i; 211 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 212 return &dev->tx_context[i]; 213 } 214 } 215 216 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 217 return NULL; 218 } 219 220 /* releases a tx context 221 */ 222 static void gs_free_tx_context(struct gs_tx_context *txc) 223 { 224 txc->echo_id = GS_MAX_TX_URBS; 225 } 226 227 /* Get a tx context by id. 228 */ 229 static struct gs_tx_context *gs_get_tx_context(struct gs_can *dev, 230 unsigned int id) 231 { 232 unsigned long flags; 233 234 if (id < GS_MAX_TX_URBS) { 235 spin_lock_irqsave(&dev->tx_ctx_lock, flags); 236 if (dev->tx_context[id].echo_id == id) { 237 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 238 return &dev->tx_context[id]; 239 } 240 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); 241 } 242 return NULL; 243 } 244 245 static int gs_cmd_reset(struct gs_can *gsdev) 246 { 247 struct gs_device_mode *dm; 248 struct usb_interface *intf = gsdev->iface; 249 int rc; 250 251 dm = kzalloc(sizeof(*dm), GFP_KERNEL); 252 if (!dm) 253 return -ENOMEM; 254 255 dm->mode = GS_CAN_MODE_RESET; 256 257 rc = usb_control_msg(interface_to_usbdev(intf), 258 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 259 GS_USB_BREQ_MODE, 260 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 261 gsdev->channel, 262 0, 263 dm, 264 sizeof(*dm), 265 1000); 266 267 kfree(dm); 268 269 return rc; 270 } 271 272 static void gs_update_state(struct gs_can *dev, struct can_frame *cf) 273 { 274 struct can_device_stats *can_stats = &dev->can.can_stats; 275 276 if (cf->can_id & CAN_ERR_RESTARTED) { 277 dev->can.state = CAN_STATE_ERROR_ACTIVE; 278 can_stats->restarts++; 279 } else if (cf->can_id & CAN_ERR_BUSOFF) { 280 dev->can.state = CAN_STATE_BUS_OFF; 281 can_stats->bus_off++; 282 } else if (cf->can_id & CAN_ERR_CRTL) { 283 if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) || 284 (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) { 285 dev->can.state = CAN_STATE_ERROR_WARNING; 286 can_stats->error_warning++; 287 } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) || 288 (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) { 289 dev->can.state = CAN_STATE_ERROR_PASSIVE; 290 can_stats->error_passive++; 291 } else { 292 dev->can.state = CAN_STATE_ERROR_ACTIVE; 293 } 294 } 295 } 296 297 static void gs_usb_receive_bulk_callback(struct urb *urb) 298 { 299 struct gs_usb *usbcan = urb->context; 300 struct gs_can *dev; 301 struct net_device *netdev; 302 int rc; 303 struct net_device_stats *stats; 304 struct gs_host_frame *hf = urb->transfer_buffer; 305 struct gs_tx_context *txc; 306 struct can_frame *cf; 307 struct sk_buff *skb; 308 309 BUG_ON(!usbcan); 310 311 switch (urb->status) { 312 case 0: /* success */ 313 break; 314 case -ENOENT: 315 case -ESHUTDOWN: 316 return; 317 default: 318 /* do not resubmit aborted urbs. eg: when device goes down */ 319 return; 320 } 321 322 /* device reports out of range channel id */ 323 if (hf->channel >= GS_MAX_INTF) 324 goto resubmit_urb; 325 326 dev = usbcan->canch[hf->channel]; 327 328 netdev = dev->netdev; 329 stats = &netdev->stats; 330 331 if (!netif_device_present(netdev)) 332 return; 333 334 if (hf->echo_id == -1) { /* normal rx */ 335 skb = alloc_can_skb(dev->netdev, &cf); 336 if (!skb) 337 return; 338 339 cf->can_id = le32_to_cpu(hf->can_id); 340 341 can_frame_set_cc_len(cf, hf->can_dlc, dev->can.ctrlmode); 342 memcpy(cf->data, hf->data, 8); 343 344 /* ERROR frames tell us information about the controller */ 345 if (le32_to_cpu(hf->can_id) & CAN_ERR_FLAG) 346 gs_update_state(dev, cf); 347 348 netdev->stats.rx_packets++; 349 netdev->stats.rx_bytes += hf->can_dlc; 350 351 netif_rx(skb); 352 } else { /* echo_id == hf->echo_id */ 353 if (hf->echo_id >= GS_MAX_TX_URBS) { 354 netdev_err(netdev, 355 "Unexpected out of range echo id %d\n", 356 hf->echo_id); 357 goto resubmit_urb; 358 } 359 360 netdev->stats.tx_packets++; 361 netdev->stats.tx_bytes += hf->can_dlc; 362 363 txc = gs_get_tx_context(dev, hf->echo_id); 364 365 /* bad devices send bad echo_ids. */ 366 if (!txc) { 367 netdev_err(netdev, 368 "Unexpected unused echo id %d\n", 369 hf->echo_id); 370 goto resubmit_urb; 371 } 372 373 can_get_echo_skb(netdev, hf->echo_id, NULL); 374 375 gs_free_tx_context(txc); 376 377 atomic_dec(&dev->active_tx_urbs); 378 379 netif_wake_queue(netdev); 380 } 381 382 if (hf->flags & GS_CAN_FLAG_OVERFLOW) { 383 skb = alloc_can_err_skb(netdev, &cf); 384 if (!skb) 385 goto resubmit_urb; 386 387 cf->can_id |= CAN_ERR_CRTL; 388 cf->len = CAN_ERR_DLC; 389 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; 390 stats->rx_over_errors++; 391 stats->rx_errors++; 392 netif_rx(skb); 393 } 394 395 resubmit_urb: 396 usb_fill_bulk_urb(urb, 397 usbcan->udev, 398 usb_rcvbulkpipe(usbcan->udev, GSUSB_ENDPOINT_IN), 399 hf, 400 sizeof(struct gs_host_frame), 401 gs_usb_receive_bulk_callback, 402 usbcan 403 ); 404 405 rc = usb_submit_urb(urb, GFP_ATOMIC); 406 407 /* USB failure take down all interfaces */ 408 if (rc == -ENODEV) { 409 for (rc = 0; rc < GS_MAX_INTF; rc++) { 410 if (usbcan->canch[rc]) 411 netif_device_detach(usbcan->canch[rc]->netdev); 412 } 413 } 414 } 415 416 static int gs_usb_set_bittiming(struct net_device *netdev) 417 { 418 struct gs_can *dev = netdev_priv(netdev); 419 struct can_bittiming *bt = &dev->can.bittiming; 420 struct usb_interface *intf = dev->iface; 421 int rc; 422 struct gs_device_bittiming *dbt; 423 424 dbt = kmalloc(sizeof(*dbt), GFP_KERNEL); 425 if (!dbt) 426 return -ENOMEM; 427 428 dbt->prop_seg = cpu_to_le32(bt->prop_seg); 429 dbt->phase_seg1 = cpu_to_le32(bt->phase_seg1); 430 dbt->phase_seg2 = cpu_to_le32(bt->phase_seg2); 431 dbt->sjw = cpu_to_le32(bt->sjw); 432 dbt->brp = cpu_to_le32(bt->brp); 433 434 /* request bit timings */ 435 rc = usb_control_msg(interface_to_usbdev(intf), 436 usb_sndctrlpipe(interface_to_usbdev(intf), 0), 437 GS_USB_BREQ_BITTIMING, 438 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 439 dev->channel, 440 0, 441 dbt, 442 sizeof(*dbt), 443 1000); 444 445 kfree(dbt); 446 447 if (rc < 0) 448 dev_err(netdev->dev.parent, "Couldn't set bittimings (err=%d)", 449 rc); 450 451 return (rc > 0) ? 0 : rc; 452 } 453 454 static void gs_usb_xmit_callback(struct urb *urb) 455 { 456 struct gs_tx_context *txc = urb->context; 457 struct gs_can *dev = txc->dev; 458 struct net_device *netdev = dev->netdev; 459 460 if (urb->status) 461 netdev_info(netdev, "usb xmit fail %d\n", txc->echo_id); 462 463 usb_free_coherent(urb->dev, 464 urb->transfer_buffer_length, 465 urb->transfer_buffer, 466 urb->transfer_dma); 467 } 468 469 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb, 470 struct net_device *netdev) 471 { 472 struct gs_can *dev = netdev_priv(netdev); 473 struct net_device_stats *stats = &dev->netdev->stats; 474 struct urb *urb; 475 struct gs_host_frame *hf; 476 struct can_frame *cf; 477 int rc; 478 unsigned int idx; 479 struct gs_tx_context *txc; 480 481 if (can_dropped_invalid_skb(netdev, skb)) 482 return NETDEV_TX_OK; 483 484 /* find an empty context to keep track of transmission */ 485 txc = gs_alloc_tx_context(dev); 486 if (!txc) 487 return NETDEV_TX_BUSY; 488 489 /* create a URB, and a buffer for it */ 490 urb = usb_alloc_urb(0, GFP_ATOMIC); 491 if (!urb) 492 goto nomem_urb; 493 494 hf = usb_alloc_coherent(dev->udev, sizeof(*hf), GFP_ATOMIC, 495 &urb->transfer_dma); 496 if (!hf) { 497 netdev_err(netdev, "No memory left for USB buffer\n"); 498 goto nomem_hf; 499 } 500 501 idx = txc->echo_id; 502 503 if (idx >= GS_MAX_TX_URBS) { 504 netdev_err(netdev, "Invalid tx context %d\n", idx); 505 goto badidx; 506 } 507 508 hf->echo_id = idx; 509 hf->channel = dev->channel; 510 511 cf = (struct can_frame *)skb->data; 512 513 hf->can_id = cpu_to_le32(cf->can_id); 514 hf->can_dlc = can_get_cc_dlc(cf, dev->can.ctrlmode); 515 516 memcpy(hf->data, cf->data, cf->len); 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, 0); 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 u32 flags = 0; 585 586 rc = open_candev(netdev); 587 if (rc) 588 return rc; 589 590 if (atomic_add_return(1, &parent->active_channels) == 1) { 591 for (i = 0; i < GS_MAX_RX_URBS; i++) { 592 struct urb *urb; 593 u8 *buf; 594 595 /* alloc rx urb */ 596 urb = usb_alloc_urb(0, GFP_KERNEL); 597 if (!urb) 598 return -ENOMEM; 599 600 /* alloc rx buffer */ 601 buf = usb_alloc_coherent(dev->udev, 602 sizeof(struct gs_host_frame), 603 GFP_KERNEL, 604 &urb->transfer_dma); 605 if (!buf) { 606 netdev_err(netdev, 607 "No memory left for USB buffer\n"); 608 usb_free_urb(urb); 609 return -ENOMEM; 610 } 611 612 /* fill, anchor, and submit rx urb */ 613 usb_fill_bulk_urb(urb, 614 dev->udev, 615 usb_rcvbulkpipe(dev->udev, 616 GSUSB_ENDPOINT_IN), 617 buf, 618 sizeof(struct gs_host_frame), 619 gs_usb_receive_bulk_callback, 620 parent); 621 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 622 623 usb_anchor_urb(urb, &parent->rx_submitted); 624 625 rc = usb_submit_urb(urb, GFP_KERNEL); 626 if (rc) { 627 if (rc == -ENODEV) 628 netif_device_detach(dev->netdev); 629 630 netdev_err(netdev, 631 "usb_submit failed (err=%d)\n", 632 rc); 633 634 usb_unanchor_urb(urb); 635 usb_free_urb(urb); 636 break; 637 } 638 639 /* Drop reference, 640 * USB core will take care of freeing it 641 */ 642 usb_free_urb(urb); 643 } 644 } 645 646 dm = kmalloc(sizeof(*dm), GFP_KERNEL); 647 if (!dm) 648 return -ENOMEM; 649 650 /* flags */ 651 ctrlmode = dev->can.ctrlmode; 652 653 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 654 flags |= GS_CAN_MODE_LOOP_BACK; 655 else if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 656 flags |= GS_CAN_MODE_LISTEN_ONLY; 657 658 /* Controller is not allowed to retry TX 659 * this mode is unavailable on atmels uc3c hardware 660 */ 661 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) 662 flags |= GS_CAN_MODE_ONE_SHOT; 663 664 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES) 665 flags |= GS_CAN_MODE_TRIPLE_SAMPLE; 666 667 /* finally start device */ 668 dm->mode = cpu_to_le32(GS_CAN_MODE_START); 669 dm->flags = cpu_to_le32(flags); 670 rc = usb_control_msg(interface_to_usbdev(dev->iface), 671 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 0), 672 GS_USB_BREQ_MODE, 673 USB_DIR_OUT | USB_TYPE_VENDOR | 674 USB_RECIP_INTERFACE, 675 dev->channel, 676 0, 677 dm, 678 sizeof(*dm), 679 1000); 680 681 if (rc < 0) { 682 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc); 683 kfree(dm); 684 return rc; 685 } 686 687 kfree(dm); 688 689 dev->can.state = CAN_STATE_ERROR_ACTIVE; 690 691 if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)) 692 netif_start_queue(netdev); 693 694 return 0; 695 } 696 697 static int gs_can_close(struct net_device *netdev) 698 { 699 int rc; 700 struct gs_can *dev = netdev_priv(netdev); 701 struct gs_usb *parent = dev->parent; 702 703 netif_stop_queue(netdev); 704 705 /* Stop polling */ 706 if (atomic_dec_and_test(&parent->active_channels)) 707 usb_kill_anchored_urbs(&parent->rx_submitted); 708 709 /* Stop sending URBs */ 710 usb_kill_anchored_urbs(&dev->tx_submitted); 711 atomic_set(&dev->active_tx_urbs, 0); 712 713 /* reset the device */ 714 rc = gs_cmd_reset(dev); 715 if (rc < 0) 716 netdev_warn(netdev, "Couldn't shutdown device (err=%d)", rc); 717 718 /* reset tx contexts */ 719 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 720 dev->tx_context[rc].dev = dev; 721 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 722 } 723 724 /* close the netdev */ 725 close_candev(netdev); 726 727 return 0; 728 } 729 730 static const struct net_device_ops gs_usb_netdev_ops = { 731 .ndo_open = gs_can_open, 732 .ndo_stop = gs_can_close, 733 .ndo_start_xmit = gs_can_start_xmit, 734 .ndo_change_mtu = can_change_mtu, 735 }; 736 737 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify) 738 { 739 struct gs_can *dev = netdev_priv(netdev); 740 struct gs_identify_mode *imode; 741 int rc; 742 743 imode = kmalloc(sizeof(*imode), GFP_KERNEL); 744 745 if (!imode) 746 return -ENOMEM; 747 748 if (do_identify) 749 imode->mode = cpu_to_le32(GS_CAN_IDENTIFY_ON); 750 else 751 imode->mode = cpu_to_le32(GS_CAN_IDENTIFY_OFF); 752 753 rc = usb_control_msg(interface_to_usbdev(dev->iface), 754 usb_sndctrlpipe(interface_to_usbdev(dev->iface), 755 0), 756 GS_USB_BREQ_IDENTIFY, 757 USB_DIR_OUT | USB_TYPE_VENDOR | 758 USB_RECIP_INTERFACE, 759 dev->channel, 760 0, 761 imode, 762 sizeof(*imode), 763 100); 764 765 kfree(imode); 766 767 return (rc > 0) ? 0 : rc; 768 } 769 770 /* blink LED's for finding the this interface */ 771 static int gs_usb_set_phys_id(struct net_device *dev, 772 enum ethtool_phys_id_state state) 773 { 774 int rc = 0; 775 776 switch (state) { 777 case ETHTOOL_ID_ACTIVE: 778 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_ON); 779 break; 780 case ETHTOOL_ID_INACTIVE: 781 rc = gs_usb_set_identify(dev, GS_CAN_IDENTIFY_OFF); 782 break; 783 default: 784 break; 785 } 786 787 return rc; 788 } 789 790 static const struct ethtool_ops gs_usb_ethtool_ops = { 791 .set_phys_id = gs_usb_set_phys_id, 792 }; 793 794 static struct gs_can *gs_make_candev(unsigned int channel, 795 struct usb_interface *intf, 796 struct gs_device_config *dconf) 797 { 798 struct gs_can *dev; 799 struct net_device *netdev; 800 int rc; 801 struct gs_device_bt_const *bt_const; 802 u32 feature; 803 804 bt_const = kmalloc(sizeof(*bt_const), GFP_KERNEL); 805 if (!bt_const) 806 return ERR_PTR(-ENOMEM); 807 808 /* fetch bit timing constants */ 809 rc = usb_control_msg(interface_to_usbdev(intf), 810 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 811 GS_USB_BREQ_BT_CONST, 812 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 813 channel, 814 0, 815 bt_const, 816 sizeof(*bt_const), 817 1000); 818 819 if (rc < 0) { 820 dev_err(&intf->dev, 821 "Couldn't get bit timing const for channel (err=%d)\n", 822 rc); 823 kfree(bt_const); 824 return ERR_PTR(rc); 825 } 826 827 /* create netdev */ 828 netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS); 829 if (!netdev) { 830 dev_err(&intf->dev, "Couldn't allocate candev\n"); 831 kfree(bt_const); 832 return ERR_PTR(-ENOMEM); 833 } 834 835 dev = netdev_priv(netdev); 836 837 netdev->netdev_ops = &gs_usb_netdev_ops; 838 839 netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */ 840 841 /* dev setup */ 842 strcpy(dev->bt_const.name, "gs_usb"); 843 dev->bt_const.tseg1_min = le32_to_cpu(bt_const->tseg1_min); 844 dev->bt_const.tseg1_max = le32_to_cpu(bt_const->tseg1_max); 845 dev->bt_const.tseg2_min = le32_to_cpu(bt_const->tseg2_min); 846 dev->bt_const.tseg2_max = le32_to_cpu(bt_const->tseg2_max); 847 dev->bt_const.sjw_max = le32_to_cpu(bt_const->sjw_max); 848 dev->bt_const.brp_min = le32_to_cpu(bt_const->brp_min); 849 dev->bt_const.brp_max = le32_to_cpu(bt_const->brp_max); 850 dev->bt_const.brp_inc = le32_to_cpu(bt_const->brp_inc); 851 852 dev->udev = interface_to_usbdev(intf); 853 dev->iface = intf; 854 dev->netdev = netdev; 855 dev->channel = channel; 856 857 init_usb_anchor(&dev->tx_submitted); 858 atomic_set(&dev->active_tx_urbs, 0); 859 spin_lock_init(&dev->tx_ctx_lock); 860 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 861 dev->tx_context[rc].dev = dev; 862 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 863 } 864 865 /* can setup */ 866 dev->can.state = CAN_STATE_STOPPED; 867 dev->can.clock.freq = le32_to_cpu(bt_const->fclk_can); 868 dev->can.bittiming_const = &dev->bt_const; 869 dev->can.do_set_bittiming = gs_usb_set_bittiming; 870 871 dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC; 872 873 feature = le32_to_cpu(bt_const->feature); 874 if (feature & GS_CAN_FEATURE_LISTEN_ONLY) 875 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY; 876 877 if (feature & GS_CAN_FEATURE_LOOP_BACK) 878 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK; 879 880 if (feature & GS_CAN_FEATURE_TRIPLE_SAMPLE) 881 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; 882 883 if (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 (le32_to_cpu(dconf->sw_version) > 1) 889 if (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 = cpu_to_le32(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->cur_altsetting->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->cur_altsetting->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