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 device_detach; 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 %u\n", 356 hf->echo_id); 357 goto resubmit_urb; 358 } 359 360 txc = gs_get_tx_context(dev, hf->echo_id); 361 362 /* bad devices send bad echo_ids. */ 363 if (!txc) { 364 netdev_err(netdev, 365 "Unexpected unused echo id %u\n", 366 hf->echo_id); 367 goto resubmit_urb; 368 } 369 370 netdev->stats.tx_packets++; 371 netdev->stats.tx_bytes += can_get_echo_skb(netdev, hf->echo_id, 372 NULL); 373 374 gs_free_tx_context(txc); 375 376 atomic_dec(&dev->active_tx_urbs); 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->len = 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 device_detach: 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 %u\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 %u\n", idx); 505 goto badidx; 506 } 507 508 hf->echo_id = idx; 509 hf->channel = dev->channel; 510 hf->flags = 0; 511 hf->reserved = 0; 512 513 cf = (struct can_frame *)skb->data; 514 515 hf->can_id = cpu_to_le32(cf->can_id); 516 hf->can_dlc = can_get_cc_dlc(cf, dev->can.ctrlmode); 517 518 memcpy(hf->data, cf->data, cf->len); 519 520 usb_fill_bulk_urb(urb, dev->udev, 521 usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT), 522 hf, 523 sizeof(*hf), 524 gs_usb_xmit_callback, 525 txc); 526 527 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 528 usb_anchor_urb(urb, &dev->tx_submitted); 529 530 can_put_echo_skb(skb, netdev, idx, 0); 531 532 atomic_inc(&dev->active_tx_urbs); 533 534 rc = usb_submit_urb(urb, GFP_ATOMIC); 535 if (unlikely(rc)) { /* usb send failed */ 536 atomic_dec(&dev->active_tx_urbs); 537 538 can_free_echo_skb(netdev, idx, NULL); 539 gs_free_tx_context(txc); 540 541 usb_unanchor_urb(urb); 542 usb_free_coherent(dev->udev, 543 sizeof(*hf), 544 hf, 545 urb->transfer_dma); 546 547 if (rc == -ENODEV) { 548 netif_device_detach(netdev); 549 } else { 550 netdev_err(netdev, "usb_submit failed (err=%d)\n", rc); 551 stats->tx_dropped++; 552 } 553 } else { 554 /* Slow down tx path */ 555 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS) 556 netif_stop_queue(netdev); 557 } 558 559 /* let usb core take care of this urb */ 560 usb_free_urb(urb); 561 562 return NETDEV_TX_OK; 563 564 badidx: 565 usb_free_coherent(dev->udev, 566 sizeof(*hf), 567 hf, 568 urb->transfer_dma); 569 nomem_hf: 570 usb_free_urb(urb); 571 572 nomem_urb: 573 gs_free_tx_context(txc); 574 dev_kfree_skb(skb); 575 stats->tx_dropped++; 576 return NETDEV_TX_OK; 577 } 578 579 static int gs_can_open(struct net_device *netdev) 580 { 581 struct gs_can *dev = netdev_priv(netdev); 582 struct gs_usb *parent = dev->parent; 583 int rc, i; 584 struct gs_device_mode *dm; 585 u32 ctrlmode; 586 u32 flags = 0; 587 588 rc = open_candev(netdev); 589 if (rc) 590 return rc; 591 592 if (atomic_add_return(1, &parent->active_channels) == 1) { 593 for (i = 0; i < GS_MAX_RX_URBS; i++) { 594 struct urb *urb; 595 u8 *buf; 596 597 /* alloc rx urb */ 598 urb = usb_alloc_urb(0, GFP_KERNEL); 599 if (!urb) 600 return -ENOMEM; 601 602 /* alloc rx buffer */ 603 buf = usb_alloc_coherent(dev->udev, 604 sizeof(struct gs_host_frame), 605 GFP_KERNEL, 606 &urb->transfer_dma); 607 if (!buf) { 608 netdev_err(netdev, 609 "No memory left for USB buffer\n"); 610 usb_free_urb(urb); 611 return -ENOMEM; 612 } 613 614 /* fill, anchor, and submit rx urb */ 615 usb_fill_bulk_urb(urb, 616 dev->udev, 617 usb_rcvbulkpipe(dev->udev, 618 GSUSB_ENDPOINT_IN), 619 buf, 620 sizeof(struct gs_host_frame), 621 gs_usb_receive_bulk_callback, 622 parent); 623 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 624 625 usb_anchor_urb(urb, &parent->rx_submitted); 626 627 rc = usb_submit_urb(urb, GFP_KERNEL); 628 if (rc) { 629 if (rc == -ENODEV) 630 netif_device_detach(dev->netdev); 631 632 netdev_err(netdev, 633 "usb_submit failed (err=%d)\n", 634 rc); 635 636 usb_unanchor_urb(urb); 637 usb_free_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; 654 655 if (ctrlmode & CAN_CTRLMODE_LOOPBACK) 656 flags |= GS_CAN_MODE_LOOP_BACK; 657 else if (ctrlmode & CAN_CTRLMODE_LISTENONLY) 658 flags |= GS_CAN_MODE_LISTEN_ONLY; 659 660 /* Controller is not allowed to retry TX 661 * this mode is unavailable on atmels uc3c hardware 662 */ 663 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) 664 flags |= GS_CAN_MODE_ONE_SHOT; 665 666 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES) 667 flags |= GS_CAN_MODE_TRIPLE_SAMPLE; 668 669 /* finally start device */ 670 dm->mode = cpu_to_le32(GS_CAN_MODE_START); 671 dm->flags = cpu_to_le32(flags); 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(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 = cpu_to_le32(GS_CAN_IDENTIFY_ON); 752 else 753 imode->mode = cpu_to_le32(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 u32 feature; 805 806 bt_const = kmalloc(sizeof(*bt_const), GFP_KERNEL); 807 if (!bt_const) 808 return ERR_PTR(-ENOMEM); 809 810 /* fetch bit timing constants */ 811 rc = usb_control_msg(interface_to_usbdev(intf), 812 usb_rcvctrlpipe(interface_to_usbdev(intf), 0), 813 GS_USB_BREQ_BT_CONST, 814 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE, 815 channel, 816 0, 817 bt_const, 818 sizeof(*bt_const), 819 1000); 820 821 if (rc < 0) { 822 dev_err(&intf->dev, 823 "Couldn't get bit timing const for channel (err=%d)\n", 824 rc); 825 kfree(bt_const); 826 return ERR_PTR(rc); 827 } 828 829 /* create netdev */ 830 netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS); 831 if (!netdev) { 832 dev_err(&intf->dev, "Couldn't allocate candev\n"); 833 kfree(bt_const); 834 return ERR_PTR(-ENOMEM); 835 } 836 837 dev = netdev_priv(netdev); 838 839 netdev->netdev_ops = &gs_usb_netdev_ops; 840 841 netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */ 842 843 /* dev setup */ 844 strcpy(dev->bt_const.name, "gs_usb"); 845 dev->bt_const.tseg1_min = le32_to_cpu(bt_const->tseg1_min); 846 dev->bt_const.tseg1_max = le32_to_cpu(bt_const->tseg1_max); 847 dev->bt_const.tseg2_min = le32_to_cpu(bt_const->tseg2_min); 848 dev->bt_const.tseg2_max = le32_to_cpu(bt_const->tseg2_max); 849 dev->bt_const.sjw_max = le32_to_cpu(bt_const->sjw_max); 850 dev->bt_const.brp_min = le32_to_cpu(bt_const->brp_min); 851 dev->bt_const.brp_max = le32_to_cpu(bt_const->brp_max); 852 dev->bt_const.brp_inc = le32_to_cpu(bt_const->brp_inc); 853 854 dev->udev = interface_to_usbdev(intf); 855 dev->iface = intf; 856 dev->netdev = netdev; 857 dev->channel = channel; 858 859 init_usb_anchor(&dev->tx_submitted); 860 atomic_set(&dev->active_tx_urbs, 0); 861 spin_lock_init(&dev->tx_ctx_lock); 862 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { 863 dev->tx_context[rc].dev = dev; 864 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; 865 } 866 867 /* can setup */ 868 dev->can.state = CAN_STATE_STOPPED; 869 dev->can.clock.freq = le32_to_cpu(bt_const->fclk_can); 870 dev->can.bittiming_const = &dev->bt_const; 871 dev->can.do_set_bittiming = gs_usb_set_bittiming; 872 873 dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC; 874 875 feature = le32_to_cpu(bt_const->feature); 876 if (feature & GS_CAN_FEATURE_LISTEN_ONLY) 877 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY; 878 879 if (feature & GS_CAN_FEATURE_LOOP_BACK) 880 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK; 881 882 if (feature & GS_CAN_FEATURE_TRIPLE_SAMPLE) 883 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; 884 885 if (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 (le32_to_cpu(dconf->sw_version) > 1) 891 if (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 = cpu_to_le32(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->cur_altsetting->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->cur_altsetting->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 %u interfaces\n", icount); 970 971 if (icount > GS_MAX_INTF) { 972 dev_err(&intf->dev, 973 "Driver cannot handle more that %u 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