1 // SPDX-License-Identifier: GPL-2.0-only
3 * CAN driver for PEAK System USB adapters
4 * Derived from the PCAN project file driver/src/pcan_usb_core.c
6 * Copyright (C) 2003-2010 PEAK System-Technik GmbH
7 * Copyright (C) 2010-2012 Stephane Grosjean <s.grosjean@peak-system.com>
9 * Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de>
11 #include <linux/init.h>
12 #include <linux/signal.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/netdevice.h>
16 #include <linux/usb.h>
18 #include <linux/can.h>
19 #include <linux/can/dev.h>
20 #include <linux/can/error.h>
22 #include "pcan_usb_core.h"
24 MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
25 MODULE_DESCRIPTION("CAN driver for PEAK-System USB adapters");
26 MODULE_LICENSE("GPL v2");
28 /* Table of devices that work with this driver */
29 static struct usb_device_id peak_usb_table[] = {
30 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USB_PRODUCT_ID)},
31 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPRO_PRODUCT_ID)},
32 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBFD_PRODUCT_ID)},
33 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPROFD_PRODUCT_ID)},
34 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBCHIP_PRODUCT_ID)},
35 {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBX6_PRODUCT_ID)},
36 {} /* Terminating entry */
39 MODULE_DEVICE_TABLE(usb, peak_usb_table);
41 /* List of supported PCAN-USB adapters (NULL terminated list) */
42 static const struct peak_usb_adapter *const peak_usb_adapters_list[] = {
55 void pcan_dump_mem(char *prompt, void *p, int l)
57 pr_info("%s dumping %s (%d bytes):\n",
58 PCAN_USB_DRIVER_NAME, prompt ? prompt : "memory", l);
59 print_hex_dump(KERN_INFO, PCAN_USB_DRIVER_NAME " ", DUMP_PREFIX_NONE,
60 DUMP_WIDTH, 1, p, l, false);
64 * initialize a time_ref object with usb adapter own settings
66 void peak_usb_init_time_ref(struct peak_time_ref *time_ref,
67 const struct peak_usb_adapter *adapter)
70 memset(time_ref, 0, sizeof(struct peak_time_ref));
71 time_ref->adapter = adapter;
76 * sometimes, another now may be more recent than current one...
78 void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
80 time_ref->ts_dev_2 = ts_now;
82 /* should wait at least two passes before computing */
83 if (ktime_to_ns(time_ref->tv_host) > 0) {
84 u32 delta_ts = time_ref->ts_dev_2 - time_ref->ts_dev_1;
86 if (time_ref->ts_dev_2 < time_ref->ts_dev_1)
87 delta_ts &= (1 << time_ref->adapter->ts_used_bits) - 1;
89 time_ref->ts_total += delta_ts;
94 * register device timestamp as now
96 void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now)
98 if (ktime_to_ns(time_ref->tv_host_0) == 0) {
99 /* use monotonic clock to correctly compute further deltas */
100 time_ref->tv_host_0 = ktime_get();
101 time_ref->tv_host = ktime_set(0, 0);
104 * delta_us should not be >= 2^32 => delta should be < 4294s
105 * handle 32-bits wrapping here: if count of s. reaches 4200,
106 * reset counters and change time base
108 if (ktime_to_ns(time_ref->tv_host)) {
109 ktime_t delta = ktime_sub(time_ref->tv_host,
110 time_ref->tv_host_0);
111 if (ktime_to_ns(delta) > (4200ull * NSEC_PER_SEC)) {
112 time_ref->tv_host_0 = time_ref->tv_host;
113 time_ref->ts_total = 0;
117 time_ref->tv_host = ktime_get();
118 time_ref->tick_count++;
121 time_ref->ts_dev_1 = time_ref->ts_dev_2;
122 peak_usb_update_ts_now(time_ref, ts_now);
126 * compute time according to current ts and time_ref data
128 void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time)
130 /* protect from getting time before setting now */
131 if (ktime_to_ns(time_ref->tv_host)) {
134 delta_us = ts - time_ref->ts_dev_2;
135 if (ts < time_ref->ts_dev_2)
136 delta_us &= (1 << time_ref->adapter->ts_used_bits) - 1;
138 delta_us += time_ref->ts_total;
140 delta_us *= time_ref->adapter->us_per_ts_scale;
141 delta_us >>= time_ref->adapter->us_per_ts_shift;
143 *time = ktime_add_us(time_ref->tv_host_0, delta_us);
150 * post received skb after having set any hw timestamp
152 int peak_usb_netif_rx(struct sk_buff *skb,
153 struct peak_time_ref *time_ref, u32 ts_low)
155 struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
157 peak_usb_get_ts_time(time_ref, ts_low, &hwts->hwtstamp);
159 return netif_rx(skb);
163 * callback for bulk Rx urb
165 static void peak_usb_read_bulk_callback(struct urb *urb)
167 struct peak_usb_device *dev = urb->context;
168 struct net_device *netdev;
171 netdev = dev->netdev;
173 if (!netif_device_present(netdev))
176 /* check reception status */
177 switch (urb->status) {
191 "Rx urb aborted (%d)\n", urb->status);
195 /* protect from any incoming empty msgs */
196 if ((urb->actual_length > 0) && (dev->adapter->dev_decode_buf)) {
197 /* handle these kinds of msgs only if _start callback called */
198 if (dev->state & PCAN_USB_STATE_STARTED) {
199 err = dev->adapter->dev_decode_buf(dev, urb);
201 pcan_dump_mem("received usb message",
202 urb->transfer_buffer,
203 urb->transfer_buffer_length);
208 usb_fill_bulk_urb(urb, dev->udev,
209 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
210 urb->transfer_buffer, dev->adapter->rx_buffer_size,
211 peak_usb_read_bulk_callback, dev);
213 usb_anchor_urb(urb, &dev->rx_submitted);
214 err = usb_submit_urb(urb, GFP_ATOMIC);
218 usb_unanchor_urb(urb);
221 netif_device_detach(netdev);
223 netdev_err(netdev, "failed resubmitting read bulk urb: %d\n",
228 * callback for bulk Tx urb
230 static void peak_usb_write_bulk_callback(struct urb *urb)
232 struct peak_tx_urb_context *context = urb->context;
233 struct peak_usb_device *dev;
234 struct net_device *netdev;
239 netdev = dev->netdev;
241 atomic_dec(&dev->active_tx_urbs);
243 if (!netif_device_present(netdev))
246 /* check tx status */
247 switch (urb->status) {
249 /* transmission complete */
250 netdev->stats.tx_packets++;
251 netdev->stats.tx_bytes += context->data_len;
253 /* prevent tx timeout */
254 netif_trans_update(netdev);
259 netdev_err(netdev, "Tx urb aborted (%d)\n",
269 /* should always release echo skb and corresponding context */
270 can_get_echo_skb(netdev, context->echo_index);
271 context->echo_index = PCAN_USB_MAX_TX_URBS;
273 /* do wakeup tx queue in case of success only */
275 netif_wake_queue(netdev);
279 * called by netdev to send one skb on the CAN interface.
281 static netdev_tx_t peak_usb_ndo_start_xmit(struct sk_buff *skb,
282 struct net_device *netdev)
284 struct peak_usb_device *dev = netdev_priv(netdev);
285 struct peak_tx_urb_context *context = NULL;
286 struct net_device_stats *stats = &netdev->stats;
287 struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
291 size_t size = dev->adapter->tx_buffer_size;
293 if (can_dropped_invalid_skb(netdev, skb))
296 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
297 if (dev->tx_contexts[i].echo_index == PCAN_USB_MAX_TX_URBS) {
298 context = dev->tx_contexts + i;
303 /* should not occur except during restart */
304 return NETDEV_TX_BUSY;
308 obuf = urb->transfer_buffer;
310 err = dev->adapter->dev_encode_msg(dev, skb, obuf, &size);
313 netdev_err(netdev, "packet dropped\n");
319 context->echo_index = i;
321 /* Note: this works with CANFD frames too */
322 context->data_len = cfd->len;
324 usb_anchor_urb(urb, &dev->tx_submitted);
326 can_put_echo_skb(skb, netdev, context->echo_index);
328 atomic_inc(&dev->active_tx_urbs);
330 err = usb_submit_urb(urb, GFP_ATOMIC);
332 can_free_echo_skb(netdev, context->echo_index);
334 usb_unanchor_urb(urb);
336 /* this context is not used in fact */
337 context->echo_index = PCAN_USB_MAX_TX_URBS;
339 atomic_dec(&dev->active_tx_urbs);
343 netif_device_detach(netdev);
346 netdev_warn(netdev, "tx urb submitting failed err=%d\n",
350 /* cable unplugged */
354 netif_trans_update(netdev);
356 /* slow down tx path */
357 if (atomic_read(&dev->active_tx_urbs) >= PCAN_USB_MAX_TX_URBS)
358 netif_stop_queue(netdev);
365 * start the CAN interface.
366 * Rx and Tx urbs are allocated here. Rx urbs are submitted here.
368 static int peak_usb_start(struct peak_usb_device *dev)
370 struct net_device *netdev = dev->netdev;
373 for (i = 0; i < PCAN_USB_MAX_RX_URBS; i++) {
377 /* create a URB, and a buffer for it, to receive usb messages */
378 urb = usb_alloc_urb(0, GFP_KERNEL);
384 buf = kmalloc(dev->adapter->rx_buffer_size, GFP_KERNEL);
391 usb_fill_bulk_urb(urb, dev->udev,
392 usb_rcvbulkpipe(dev->udev, dev->ep_msg_in),
393 buf, dev->adapter->rx_buffer_size,
394 peak_usb_read_bulk_callback, dev);
396 /* ask last usb_free_urb() to also kfree() transfer_buffer */
397 urb->transfer_flags |= URB_FREE_BUFFER;
398 usb_anchor_urb(urb, &dev->rx_submitted);
400 err = usb_submit_urb(urb, GFP_KERNEL);
403 netif_device_detach(dev->netdev);
405 usb_unanchor_urb(urb);
411 /* drop reference, USB core will take care of freeing it */
415 /* did we submit any URBs? Warn if we was not able to submit all urbs */
416 if (i < PCAN_USB_MAX_RX_URBS) {
418 netdev_err(netdev, "couldn't setup any rx URB\n");
422 netdev_warn(netdev, "rx performance may be slow\n");
425 /* pre-alloc tx buffers and corresponding urbs */
426 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
427 struct peak_tx_urb_context *context;
431 /* create a URB and a buffer for it, to transmit usb messages */
432 urb = usb_alloc_urb(0, GFP_KERNEL);
438 buf = kmalloc(dev->adapter->tx_buffer_size, GFP_KERNEL);
445 context = dev->tx_contexts + i;
449 usb_fill_bulk_urb(urb, dev->udev,
450 usb_sndbulkpipe(dev->udev, dev->ep_msg_out),
451 buf, dev->adapter->tx_buffer_size,
452 peak_usb_write_bulk_callback, context);
454 /* ask last usb_free_urb() to also kfree() transfer_buffer */
455 urb->transfer_flags |= URB_FREE_BUFFER;
458 /* warn if we were not able to allocate enough tx contexts */
459 if (i < PCAN_USB_MAX_TX_URBS) {
461 netdev_err(netdev, "couldn't setup any tx URB\n");
465 netdev_warn(netdev, "tx performance may be slow\n");
468 if (dev->adapter->dev_start) {
469 err = dev->adapter->dev_start(dev);
474 dev->state |= PCAN_USB_STATE_STARTED;
476 /* can set bus on now */
477 if (dev->adapter->dev_set_bus) {
478 err = dev->adapter->dev_set_bus(dev, 1);
483 dev->can.state = CAN_STATE_ERROR_ACTIVE;
489 netif_device_detach(dev->netdev);
491 netdev_warn(netdev, "couldn't submit control: %d\n", err);
493 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
494 usb_free_urb(dev->tx_contexts[i].urb);
495 dev->tx_contexts[i].urb = NULL;
498 usb_kill_anchored_urbs(&dev->rx_submitted);
504 * called by netdev to open the corresponding CAN interface.
506 static int peak_usb_ndo_open(struct net_device *netdev)
508 struct peak_usb_device *dev = netdev_priv(netdev);
512 err = open_candev(netdev);
516 /* finally start device */
517 err = peak_usb_start(dev);
519 netdev_err(netdev, "couldn't start device: %d\n", err);
520 close_candev(netdev);
524 netif_start_queue(netdev);
530 * unlink in-flight Rx and Tx urbs and free their memory.
532 static void peak_usb_unlink_all_urbs(struct peak_usb_device *dev)
536 /* free all Rx (submitted) urbs */
537 usb_kill_anchored_urbs(&dev->rx_submitted);
539 /* free unsubmitted Tx urbs first */
540 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) {
541 struct urb *urb = dev->tx_contexts[i].urb;
544 dev->tx_contexts[i].echo_index != PCAN_USB_MAX_TX_URBS) {
546 * this urb is already released or always submitted,
547 * let usb core free by itself
553 dev->tx_contexts[i].urb = NULL;
556 /* then free all submitted Tx urbs */
557 usb_kill_anchored_urbs(&dev->tx_submitted);
558 atomic_set(&dev->active_tx_urbs, 0);
562 * called by netdev to close the corresponding CAN interface.
564 static int peak_usb_ndo_stop(struct net_device *netdev)
566 struct peak_usb_device *dev = netdev_priv(netdev);
568 dev->state &= ~PCAN_USB_STATE_STARTED;
569 netif_stop_queue(netdev);
571 close_candev(netdev);
573 dev->can.state = CAN_STATE_STOPPED;
575 /* unlink all pending urbs and free used memory */
576 peak_usb_unlink_all_urbs(dev);
578 if (dev->adapter->dev_stop)
579 dev->adapter->dev_stop(dev);
581 /* can set bus off now */
582 if (dev->adapter->dev_set_bus) {
583 int err = dev->adapter->dev_set_bus(dev, 0);
592 * handle end of waiting for the device to reset
594 void peak_usb_restart_complete(struct peak_usb_device *dev)
596 /* finally MUST update can state */
597 dev->can.state = CAN_STATE_ERROR_ACTIVE;
599 /* netdev queue can be awaken now */
600 netif_wake_queue(dev->netdev);
603 void peak_usb_async_complete(struct urb *urb)
605 kfree(urb->transfer_buffer);
610 * device (auto-)restart mechanism runs in a timer context =>
611 * MUST handle restart with asynchronous usb transfers
613 static int peak_usb_restart(struct peak_usb_device *dev)
620 * if device doesn't define any asynchronous restart handler, simply
621 * wake the netdev queue up
623 if (!dev->adapter->dev_restart_async) {
624 peak_usb_restart_complete(dev);
628 /* first allocate a urb to handle the asynchronous steps */
629 urb = usb_alloc_urb(0, GFP_ATOMIC);
633 /* also allocate enough space for the commands to send */
634 buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_ATOMIC);
640 /* call the device specific handler for the restart */
641 err = dev->adapter->dev_restart_async(dev, urb, buf);
652 * candev callback used to change CAN mode.
653 * Warning: this is called from a timer context!
655 static int peak_usb_set_mode(struct net_device *netdev, enum can_mode mode)
657 struct peak_usb_device *dev = netdev_priv(netdev);
662 err = peak_usb_restart(dev);
664 netdev_err(netdev, "couldn't start device (err %d)\n",
676 * candev callback used to set device nominal/arbitration bitrate.
678 static int peak_usb_set_bittiming(struct net_device *netdev)
680 struct peak_usb_device *dev = netdev_priv(netdev);
681 const struct peak_usb_adapter *pa = dev->adapter;
683 if (pa->dev_set_bittiming) {
684 struct can_bittiming *bt = &dev->can.bittiming;
685 int err = pa->dev_set_bittiming(dev, bt);
688 netdev_info(netdev, "couldn't set bitrate (err %d)\n",
697 * candev callback used to set device data bitrate.
699 static int peak_usb_set_data_bittiming(struct net_device *netdev)
701 struct peak_usb_device *dev = netdev_priv(netdev);
702 const struct peak_usb_adapter *pa = dev->adapter;
704 if (pa->dev_set_data_bittiming) {
705 struct can_bittiming *bt = &dev->can.data_bittiming;
706 int err = pa->dev_set_data_bittiming(dev, bt);
710 "couldn't set data bitrate (err %d)\n",
719 static const struct net_device_ops peak_usb_netdev_ops = {
720 .ndo_open = peak_usb_ndo_open,
721 .ndo_stop = peak_usb_ndo_stop,
722 .ndo_start_xmit = peak_usb_ndo_start_xmit,
723 .ndo_change_mtu = can_change_mtu,
727 * create one device which is attached to CAN controller #ctrl_idx of the
730 static int peak_usb_create_dev(const struct peak_usb_adapter *peak_usb_adapter,
731 struct usb_interface *intf, int ctrl_idx)
733 struct usb_device *usb_dev = interface_to_usbdev(intf);
734 int sizeof_candev = peak_usb_adapter->sizeof_dev_private;
735 struct peak_usb_device *dev;
736 struct net_device *netdev;
740 if (sizeof_candev < sizeof(struct peak_usb_device))
741 sizeof_candev = sizeof(struct peak_usb_device);
743 netdev = alloc_candev(sizeof_candev, PCAN_USB_MAX_TX_URBS);
745 dev_err(&intf->dev, "%s: couldn't alloc candev\n",
746 PCAN_USB_DRIVER_NAME);
750 dev = netdev_priv(netdev);
752 /* allocate a buffer large enough to send commands */
753 dev->cmd_buf = kzalloc(PCAN_USB_MAX_CMD_LEN, GFP_KERNEL);
756 goto lbl_free_candev;
760 dev->netdev = netdev;
761 dev->adapter = peak_usb_adapter;
762 dev->ctrl_idx = ctrl_idx;
763 dev->state = PCAN_USB_STATE_CONNECTED;
765 dev->ep_msg_in = peak_usb_adapter->ep_msg_in;
766 dev->ep_msg_out = peak_usb_adapter->ep_msg_out[ctrl_idx];
768 dev->can.clock = peak_usb_adapter->clock;
769 dev->can.bittiming_const = peak_usb_adapter->bittiming_const;
770 dev->can.do_set_bittiming = peak_usb_set_bittiming;
771 dev->can.data_bittiming_const = peak_usb_adapter->data_bittiming_const;
772 dev->can.do_set_data_bittiming = peak_usb_set_data_bittiming;
773 dev->can.do_set_mode = peak_usb_set_mode;
774 dev->can.do_get_berr_counter = peak_usb_adapter->do_get_berr_counter;
775 dev->can.ctrlmode_supported = peak_usb_adapter->ctrlmode_supported;
777 netdev->netdev_ops = &peak_usb_netdev_ops;
779 netdev->flags |= IFF_ECHO; /* we support local echo */
781 init_usb_anchor(&dev->rx_submitted);
783 init_usb_anchor(&dev->tx_submitted);
784 atomic_set(&dev->active_tx_urbs, 0);
786 for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++)
787 dev->tx_contexts[i].echo_index = PCAN_USB_MAX_TX_URBS;
789 dev->prev_siblings = usb_get_intfdata(intf);
790 usb_set_intfdata(intf, dev);
792 SET_NETDEV_DEV(netdev, &intf->dev);
793 netdev->dev_id = ctrl_idx;
795 err = register_candev(netdev);
797 dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
798 goto lbl_restore_intf_data;
801 if (dev->prev_siblings)
802 (dev->prev_siblings)->next_siblings = dev;
804 /* keep hw revision into the netdevice */
805 tmp16 = le16_to_cpu(usb_dev->descriptor.bcdDevice);
806 dev->device_rev = tmp16 >> 8;
808 if (dev->adapter->dev_init) {
809 err = dev->adapter->dev_init(dev);
811 goto lbl_unregister_candev;
815 if (dev->adapter->dev_set_bus) {
816 err = dev->adapter->dev_set_bus(dev, 0);
818 goto lbl_unregister_candev;
821 /* get device number early */
822 if (dev->adapter->dev_get_device_id)
823 dev->adapter->dev_get_device_id(dev, &dev->device_number);
825 netdev_info(netdev, "attached to %s channel %u (device %u)\n",
826 peak_usb_adapter->name, ctrl_idx, dev->device_number);
830 lbl_unregister_candev:
831 unregister_candev(netdev);
833 lbl_restore_intf_data:
834 usb_set_intfdata(intf, dev->prev_siblings);
844 * called by the usb core when the device is unplugged from the system
846 static void peak_usb_disconnect(struct usb_interface *intf)
848 struct peak_usb_device *dev;
849 struct peak_usb_device *dev_prev_siblings;
851 /* unregister as many netdev devices as siblings */
852 for (dev = usb_get_intfdata(intf); dev; dev = dev_prev_siblings) {
853 struct net_device *netdev = dev->netdev;
856 dev_prev_siblings = dev->prev_siblings;
857 dev->state &= ~PCAN_USB_STATE_CONNECTED;
858 strlcpy(name, netdev->name, IFNAMSIZ);
860 unregister_netdev(netdev);
863 dev->next_siblings = NULL;
864 if (dev->adapter->dev_free)
865 dev->adapter->dev_free(dev);
868 dev_info(&intf->dev, "%s removed\n", name);
871 usb_set_intfdata(intf, NULL);
875 * probe function for new PEAK-System devices
877 static int peak_usb_probe(struct usb_interface *intf,
878 const struct usb_device_id *id)
880 struct usb_device *usb_dev = interface_to_usbdev(intf);
881 const u16 usb_id_product = le16_to_cpu(usb_dev->descriptor.idProduct);
882 const struct peak_usb_adapter *peak_usb_adapter = NULL;
883 int i, err = -ENOMEM;
885 /* get corresponding PCAN-USB adapter */
886 for (i = 0; i < ARRAY_SIZE(peak_usb_adapters_list); i++)
887 if (peak_usb_adapters_list[i]->device_id == usb_id_product) {
888 peak_usb_adapter = peak_usb_adapters_list[i];
892 if (!peak_usb_adapter) {
893 /* should never come except device_id bad usage in this file */
894 pr_err("%s: didn't find device id. 0x%x in devices list\n",
895 PCAN_USB_DRIVER_NAME, usb_id_product);
899 /* got corresponding adapter: check if it handles current interface */
900 if (peak_usb_adapter->intf_probe) {
901 err = peak_usb_adapter->intf_probe(intf);
906 for (i = 0; i < peak_usb_adapter->ctrl_count; i++) {
907 err = peak_usb_create_dev(peak_usb_adapter, intf, i);
909 /* deregister already created devices */
910 peak_usb_disconnect(intf);
918 /* usb specific object needed to register this driver with the usb subsystem */
919 static struct usb_driver peak_usb_driver = {
920 .name = PCAN_USB_DRIVER_NAME,
921 .disconnect = peak_usb_disconnect,
922 .probe = peak_usb_probe,
923 .id_table = peak_usb_table,
926 static int __init peak_usb_init(void)
930 /* register this driver with the USB subsystem */
931 err = usb_register(&peak_usb_driver);
933 pr_err("%s: usb_register failed (err %d)\n",
934 PCAN_USB_DRIVER_NAME, err);
939 static int peak_usb_do_device_exit(struct device *d, void *arg)
941 struct usb_interface *intf = to_usb_interface(d);
942 struct peak_usb_device *dev;
944 /* stop as many netdev devices as siblings */
945 for (dev = usb_get_intfdata(intf); dev; dev = dev->prev_siblings) {
946 struct net_device *netdev = dev->netdev;
948 if (netif_device_present(netdev))
949 if (dev->adapter->dev_exit)
950 dev->adapter->dev_exit(dev);
956 static void __exit peak_usb_exit(void)
960 /* last chance do send any synchronous commands here */
961 err = driver_for_each_device(&peak_usb_driver.drvwrap.driver, NULL,
962 NULL, peak_usb_do_device_exit);
964 pr_err("%s: failed to stop all can devices (err %d)\n",
965 PCAN_USB_DRIVER_NAME, err);
967 /* deregister this driver with the USB subsystem */
968 usb_deregister(&peak_usb_driver);
970 pr_info("%s: PCAN-USB interfaces driver unloaded\n",
971 PCAN_USB_DRIVER_NAME);
974 module_init(peak_usb_init);
975 module_exit(peak_usb_exit);