/* * CAN driver for PEAK System USB adapters * Derived from the PCAN project file driver/src/pcan_usb_core.c * * Copyright (C) 2003-2010 PEAK System-Technik GmbH * Copyright (C) 2010-2012 Stephane Grosjean * * Many thanks to Klaus Hitschler * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published * by the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. */ #include #include #include #include #include #include #include #include #include #include "pcan_usb_core.h" MODULE_AUTHOR("Stephane Grosjean "); MODULE_DESCRIPTION("CAN driver for PEAK-System USB adapters"); MODULE_LICENSE("GPL v2"); /* Table of devices that work with this driver */ static struct usb_device_id peak_usb_table[] = { {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USB_PRODUCT_ID)}, {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPRO_PRODUCT_ID)}, {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBFD_PRODUCT_ID)}, {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBPROFD_PRODUCT_ID)}, {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBCHIP_PRODUCT_ID)}, {USB_DEVICE(PCAN_USB_VENDOR_ID, PCAN_USBX6_PRODUCT_ID)}, {} /* Terminating entry */ }; MODULE_DEVICE_TABLE(usb, peak_usb_table); /* List of supported PCAN-USB adapters (NULL terminated list) */ static const struct peak_usb_adapter *const peak_usb_adapters_list[] = { &pcan_usb, &pcan_usb_pro, &pcan_usb_fd, &pcan_usb_pro_fd, &pcan_usb_chip, &pcan_usb_x6, }; /* * dump memory */ #define DUMP_WIDTH 16 void pcan_dump_mem(char *prompt, void *p, int l) { pr_info("%s dumping %s (%d bytes):\n", PCAN_USB_DRIVER_NAME, prompt ? prompt : "memory", l); print_hex_dump(KERN_INFO, PCAN_USB_DRIVER_NAME " ", DUMP_PREFIX_NONE, DUMP_WIDTH, 1, p, l, false); } /* * initialize a time_ref object with usb adapter own settings */ void peak_usb_init_time_ref(struct peak_time_ref *time_ref, const struct peak_usb_adapter *adapter) { if (time_ref) { memset(time_ref, 0, sizeof(struct peak_time_ref)); time_ref->adapter = adapter; } } /* * sometimes, another now may be more recent than current one... */ void peak_usb_update_ts_now(struct peak_time_ref *time_ref, u32 ts_now) { time_ref->ts_dev_2 = ts_now; /* should wait at least two passes before computing */ if (ktime_to_ns(time_ref->tv_host) > 0) { u32 delta_ts = time_ref->ts_dev_2 - time_ref->ts_dev_1; if (time_ref->ts_dev_2 < time_ref->ts_dev_1) delta_ts &= (1 << time_ref->adapter->ts_used_bits) - 1; time_ref->ts_total += delta_ts; } } /* * register device timestamp as now */ void peak_usb_set_ts_now(struct peak_time_ref *time_ref, u32 ts_now) { if (ktime_to_ns(time_ref->tv_host_0) == 0) { /* use monotonic clock to correctly compute further deltas */ time_ref->tv_host_0 = ktime_get(); time_ref->tv_host = ktime_set(0, 0); } else { /* * delta_us should not be >= 2^32 => delta should be < 4294s * handle 32-bits wrapping here: if count of s. reaches 4200, * reset counters and change time base */ if (ktime_to_ns(time_ref->tv_host)) { ktime_t delta = ktime_sub(time_ref->tv_host, time_ref->tv_host_0); if (ktime_to_ns(delta) > (4200ull * NSEC_PER_SEC)) { time_ref->tv_host_0 = time_ref->tv_host; time_ref->ts_total = 0; } } time_ref->tv_host = ktime_get(); time_ref->tick_count++; } time_ref->ts_dev_1 = time_ref->ts_dev_2; peak_usb_update_ts_now(time_ref, ts_now); } /* * compute time according to current ts and time_ref data */ void peak_usb_get_ts_time(struct peak_time_ref *time_ref, u32 ts, ktime_t *time) { /* protect from getting time before setting now */ if (ktime_to_ns(time_ref->tv_host)) { u64 delta_us; delta_us = ts - time_ref->ts_dev_2; if (ts < time_ref->ts_dev_2) delta_us &= (1 << time_ref->adapter->ts_used_bits) - 1; delta_us += time_ref->ts_total; delta_us *= time_ref->adapter->us_per_ts_scale; delta_us >>= time_ref->adapter->us_per_ts_shift; *time = ktime_add_us(time_ref->tv_host_0, delta_us); } else { *time = ktime_get(); } } /* * post received skb after having set any hw timestamp */ int peak_usb_netif_rx(struct sk_buff *skb, struct peak_time_ref *time_ref, u32 ts_low) { struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb); peak_usb_get_ts_time(time_ref, ts_low, &hwts->hwtstamp); return netif_rx(skb); } /* * callback for bulk Rx urb */ static void peak_usb_read_bulk_callback(struct urb *urb) { struct peak_usb_device *dev = urb->context; struct net_device *netdev; int err; netdev = dev->netdev; if (!netif_device_present(netdev)) return; /* check reception status */ switch (urb->status) { case 0: /* success */ break; case -EILSEQ: case -ENOENT: case -ECONNRESET: case -ESHUTDOWN: return; default: if (net_ratelimit()) netdev_err(netdev, "Rx urb aborted (%d)\n", urb->status); goto resubmit_urb; } /* protect from any incoming empty msgs */ if ((urb->actual_length > 0) && (dev->adapter->dev_decode_buf)) { /* handle these kinds of msgs only if _start callback called */ if (dev->state & PCAN_USB_STATE_STARTED) { err = dev->adapter->dev_decode_buf(dev, urb); if (err) pcan_dump_mem("received usb message", urb->transfer_buffer, urb->transfer_buffer_length); } } resubmit_urb: usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep_msg_in), urb->transfer_buffer, dev->adapter->rx_buffer_size, peak_usb_read_bulk_callback, dev); usb_anchor_urb(urb, &dev->rx_submitted); err = usb_submit_urb(urb, GFP_ATOMIC); if (!err) return; usb_unanchor_urb(urb); if (err == -ENODEV) netif_device_detach(netdev); else netdev_err(netdev, "failed resubmitting read bulk urb: %d\n", err); } /* * callback for bulk Tx urb */ static void peak_usb_write_bulk_callback(struct urb *urb) { struct peak_tx_urb_context *context = urb->context; struct peak_usb_device *dev; struct net_device *netdev; BUG_ON(!context); dev = context->dev; netdev = dev->netdev; atomic_dec(&dev->active_tx_urbs); if (!netif_device_present(netdev)) return; /* check tx status */ switch (urb->status) { case 0: /* transmission complete */ netdev->stats.tx_packets++; netdev->stats.tx_bytes += context->data_len; /* prevent tx timeout */ netif_trans_update(netdev); break; default: if (net_ratelimit()) netdev_err(netdev, "Tx urb aborted (%d)\n", urb->status); case -EPROTO: case -ENOENT: case -ECONNRESET: case -ESHUTDOWN: break; } /* should always release echo skb and corresponding context */ can_get_echo_skb(netdev, context->echo_index); context->echo_index = PCAN_USB_MAX_TX_URBS; /* do wakeup tx queue in case of success only */ if (!urb->status) netif_wake_queue(netdev); } /* * called by netdev to send one skb on the CAN interface. */ static netdev_tx_t peak_usb_ndo_start_xmit(struct sk_buff *skb, struct net_device *netdev) { struct peak_usb_device *dev = netdev_priv(netdev); struct peak_tx_urb_context *context = NULL; struct net_device_stats *stats = &netdev->stats; struct canfd_frame *cfd = (struct canfd_frame *)skb->data; struct urb *urb; u8 *obuf; int i, err; size_t size = dev->adapter->tx_buffer_size; if (can_dropped_invalid_skb(netdev, skb)) return NETDEV_TX_OK; for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) if (dev->tx_contexts[i].echo_index == PCAN_USB_MAX_TX_URBS) { context = dev->tx_contexts + i; break; } if (!context) { /* should not occur except during restart */ return NETDEV_TX_BUSY; } urb = context->urb; obuf = urb->transfer_buffer; err = dev->adapter->dev_encode_msg(dev, skb, obuf, &size); if (err) { if (net_ratelimit()) netdev_err(netdev, "packet dropped\n"); dev_kfree_skb(skb); stats->tx_dropped++; return NETDEV_TX_OK; } context->echo_index = i; /* Note: this works with CANFD frames too */ context->data_len = cfd->len; usb_anchor_urb(urb, &dev->tx_submitted); can_put_echo_skb(skb, netdev, context->echo_index); atomic_inc(&dev->active_tx_urbs); err = usb_submit_urb(urb, GFP_ATOMIC); if (err) { can_free_echo_skb(netdev, context->echo_index); usb_unanchor_urb(urb); /* this context is not used in fact */ context->echo_index = PCAN_USB_MAX_TX_URBS; atomic_dec(&dev->active_tx_urbs); switch (err) { case -ENODEV: netif_device_detach(netdev); break; default: netdev_warn(netdev, "tx urb submitting failed err=%d\n", err); /* fall through */ case -ENOENT: /* cable unplugged */ stats->tx_dropped++; } } else { netif_trans_update(netdev); /* slow down tx path */ if (atomic_read(&dev->active_tx_urbs) >= PCAN_USB_MAX_TX_URBS) netif_stop_queue(netdev); } return NETDEV_TX_OK; } /* * start the CAN interface. * Rx and Tx urbs are allocated here. Rx urbs are submitted here. */ static int peak_usb_start(struct peak_usb_device *dev) { struct net_device *netdev = dev->netdev; int err, i; for (i = 0; i < PCAN_USB_MAX_RX_URBS; i++) { struct urb *urb; u8 *buf; /* create a URB, and a buffer for it, to receive usb messages */ urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) { err = -ENOMEM; break; } buf = kmalloc(dev->adapter->rx_buffer_size, GFP_KERNEL); if (!buf) { usb_free_urb(urb); err = -ENOMEM; break; } usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep_msg_in), buf, dev->adapter->rx_buffer_size, peak_usb_read_bulk_callback, dev); /* ask last usb_free_urb() to also kfree() transfer_buffer */ urb->transfer_flags |= URB_FREE_BUFFER; usb_anchor_urb(urb, &dev->rx_submitted); err = usb_submit_urb(urb, GFP_KERNEL); if (err) { if (err == -ENODEV) netif_device_detach(dev->netdev); usb_unanchor_urb(urb); kfree(buf); usb_free_urb(urb); break; } /* drop reference, USB core will take care of freeing it */ usb_free_urb(urb); } /* did we submit any URBs? Warn if we was not able to submit all urbs */ if (i < PCAN_USB_MAX_RX_URBS) { if (i == 0) { netdev_err(netdev, "couldn't setup any rx URB\n"); return err; } netdev_warn(netdev, "rx performance may be slow\n"); } /* pre-alloc tx buffers and corresponding urbs */ for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) { struct peak_tx_urb_context *context; struct urb *urb; u8 *buf; /* create a URB and a buffer for it, to transmit usb messages */ urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) { err = -ENOMEM; break; } buf = kmalloc(dev->adapter->tx_buffer_size, GFP_KERNEL); if (!buf) { usb_free_urb(urb); err = -ENOMEM; break; } context = dev->tx_contexts + i; context->dev = dev; context->urb = urb; usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, dev->ep_msg_out), buf, dev->adapter->tx_buffer_size, peak_usb_write_bulk_callback, context); /* ask last usb_free_urb() to also kfree() transfer_buffer */ urb->transfer_flags |= URB_FREE_BUFFER; } /* warn if we were not able to allocate enough tx contexts */ if (i < PCAN_USB_MAX_TX_URBS) { if (i == 0) { netdev_err(netdev, "couldn't setup any tx URB\n"); goto err_tx; } netdev_warn(netdev, "tx performance may be slow\n"); } if (dev->adapter->dev_start) { err = dev->adapter->dev_start(dev); if (err) goto err_adapter; } dev->state |= PCAN_USB_STATE_STARTED; /* can set bus on now */ if (dev->adapter->dev_set_bus) { err = dev->adapter->dev_set_bus(dev, 1); if (err) goto err_adapter; } dev->can.state = CAN_STATE_ERROR_ACTIVE; return 0; err_adapter: if (err == -ENODEV) netif_device_detach(dev->netdev); netdev_warn(netdev, "couldn't submit control: %d\n", err); for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) { usb_free_urb(dev->tx_contexts[i].urb); dev->tx_contexts[i].urb = NULL; } err_tx: usb_kill_anchored_urbs(&dev->rx_submitted); return err; } /* * called by netdev to open the corresponding CAN interface. */ static int peak_usb_ndo_open(struct net_device *netdev) { struct peak_usb_device *dev = netdev_priv(netdev); int err; /* common open */ err = open_candev(netdev); if (err) return err; /* finally start device */ err = peak_usb_start(dev); if (err) { netdev_err(netdev, "couldn't start device: %d\n", err); close_candev(netdev); return err; } netif_start_queue(netdev); return 0; } /* * unlink in-flight Rx and Tx urbs and free their memory. */ static void peak_usb_unlink_all_urbs(struct peak_usb_device *dev) { int i; /* free all Rx (submitted) urbs */ usb_kill_anchored_urbs(&dev->rx_submitted); /* free unsubmitted Tx urbs first */ for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) { struct urb *urb = dev->tx_contexts[i].urb; if (!urb || dev->tx_contexts[i].echo_index != PCAN_USB_MAX_TX_URBS) { /* * this urb is already released or always submitted, * let usb core free by itself */ continue; } usb_free_urb(urb); dev->tx_contexts[i].urb = NULL; } /* then free all submitted Tx urbs */ usb_kill_anchored_urbs(&dev->tx_submitted); atomic_set(&dev->active_tx_urbs, 0); } /* * called by netdev to close the corresponding CAN interface. */ static int peak_usb_ndo_stop(struct net_device *netdev) { struct peak_usb_device *dev = netdev_priv(netdev); dev->state &= ~PCAN_USB_STATE_STARTED; netif_stop_queue(netdev); close_candev(netdev); dev->can.state = CAN_STATE_STOPPED; /* unlink all pending urbs and free used memory */ peak_usb_unlink_all_urbs(dev); if (dev->adapter->dev_stop) dev->adapter->dev_stop(dev); /* can set bus off now */ if (dev->adapter->dev_set_bus) { int err = dev->adapter->dev_set_bus(dev, 0); if (err) return err; } return 0; } /* * handle end of waiting for the device to reset */ void peak_usb_restart_complete(struct peak_usb_device *dev) { /* finally MUST update can state */ dev->can.state = CAN_STATE_ERROR_ACTIVE; /* netdev queue can be awaken now */ netif_wake_queue(dev->netdev); } void peak_usb_async_complete(struct urb *urb) { kfree(urb->transfer_buffer); usb_free_urb(urb); } /* * device (auto-)restart mechanism runs in a timer context => * MUST handle restart with asynchronous usb transfers */ static int peak_usb_restart(struct peak_usb_device *dev) { struct urb *urb; int err; u8 *buf; /* * if device doesn't define any asynchronous restart handler, simply * wake the netdev queue up */ if (!dev->adapter->dev_restart_async) { peak_usb_restart_complete(dev); return 0; } /* first allocate a urb to handle the asynchronous steps */ urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) return -ENOMEM; /* also allocate enough space for the commands to send */ buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_ATOMIC); if (!buf) { usb_free_urb(urb); return -ENOMEM; } /* call the device specific handler for the restart */ err = dev->adapter->dev_restart_async(dev, urb, buf); if (!err) return 0; kfree(buf); usb_free_urb(urb); return err; } /* * candev callback used to change CAN mode. * Warning: this is called from a timer context! */ static int peak_usb_set_mode(struct net_device *netdev, enum can_mode mode) { struct peak_usb_device *dev = netdev_priv(netdev); int err = 0; switch (mode) { case CAN_MODE_START: err = peak_usb_restart(dev); if (err) netdev_err(netdev, "couldn't start device (err %d)\n", err); break; default: return -EOPNOTSUPP; } return err; } /* * candev callback used to set device nominal/arbitration bitrate. */ static int peak_usb_set_bittiming(struct net_device *netdev) { struct peak_usb_device *dev = netdev_priv(netdev); const struct peak_usb_adapter *pa = dev->adapter; if (pa->dev_set_bittiming) { struct can_bittiming *bt = &dev->can.bittiming; int err = pa->dev_set_bittiming(dev, bt); if (err) netdev_info(netdev, "couldn't set bitrate (err %d)\n", err); return err; } return 0; } /* * candev callback used to set device data bitrate. */ static int peak_usb_set_data_bittiming(struct net_device *netdev) { struct peak_usb_device *dev = netdev_priv(netdev); const struct peak_usb_adapter *pa = dev->adapter; if (pa->dev_set_data_bittiming) { struct can_bittiming *bt = &dev->can.data_bittiming; int err = pa->dev_set_data_bittiming(dev, bt); if (err) netdev_info(netdev, "couldn't set data bitrate (err %d)\n", err); return err; } return 0; } static const struct net_device_ops peak_usb_netdev_ops = { .ndo_open = peak_usb_ndo_open, .ndo_stop = peak_usb_ndo_stop, .ndo_start_xmit = peak_usb_ndo_start_xmit, .ndo_change_mtu = can_change_mtu, }; /* * create one device which is attached to CAN controller #ctrl_idx of the * usb adapter. */ static int peak_usb_create_dev(const struct peak_usb_adapter *peak_usb_adapter, struct usb_interface *intf, int ctrl_idx) { struct usb_device *usb_dev = interface_to_usbdev(intf); int sizeof_candev = peak_usb_adapter->sizeof_dev_private; struct peak_usb_device *dev; struct net_device *netdev; int i, err; u16 tmp16; if (sizeof_candev < sizeof(struct peak_usb_device)) sizeof_candev = sizeof(struct peak_usb_device); netdev = alloc_candev(sizeof_candev, PCAN_USB_MAX_TX_URBS); if (!netdev) { dev_err(&intf->dev, "%s: couldn't alloc candev\n", PCAN_USB_DRIVER_NAME); return -ENOMEM; } dev = netdev_priv(netdev); /* allocate a buffer large enough to send commands */ dev->cmd_buf = kmalloc(PCAN_USB_MAX_CMD_LEN, GFP_KERNEL); if (!dev->cmd_buf) { err = -ENOMEM; goto lbl_free_candev; } dev->udev = usb_dev; dev->netdev = netdev; dev->adapter = peak_usb_adapter; dev->ctrl_idx = ctrl_idx; dev->state = PCAN_USB_STATE_CONNECTED; dev->ep_msg_in = peak_usb_adapter->ep_msg_in; dev->ep_msg_out = peak_usb_adapter->ep_msg_out[ctrl_idx]; dev->can.clock = peak_usb_adapter->clock; dev->can.bittiming_const = peak_usb_adapter->bittiming_const; dev->can.do_set_bittiming = peak_usb_set_bittiming; dev->can.data_bittiming_const = peak_usb_adapter->data_bittiming_const; dev->can.do_set_data_bittiming = peak_usb_set_data_bittiming; dev->can.do_set_mode = peak_usb_set_mode; dev->can.do_get_berr_counter = peak_usb_adapter->do_get_berr_counter; dev->can.ctrlmode_supported = peak_usb_adapter->ctrlmode_supported; netdev->netdev_ops = &peak_usb_netdev_ops; netdev->flags |= IFF_ECHO; /* we support local echo */ init_usb_anchor(&dev->rx_submitted); init_usb_anchor(&dev->tx_submitted); atomic_set(&dev->active_tx_urbs, 0); for (i = 0; i < PCAN_USB_MAX_TX_URBS; i++) dev->tx_contexts[i].echo_index = PCAN_USB_MAX_TX_URBS; dev->prev_siblings = usb_get_intfdata(intf); usb_set_intfdata(intf, dev); SET_NETDEV_DEV(netdev, &intf->dev); netdev->dev_id = ctrl_idx; err = register_candev(netdev); if (err) { dev_err(&intf->dev, "couldn't register CAN device: %d\n", err); goto lbl_restore_intf_data; } if (dev->prev_siblings) (dev->prev_siblings)->next_siblings = dev; /* keep hw revision into the netdevice */ tmp16 = le16_to_cpu(usb_dev->descriptor.bcdDevice); dev->device_rev = tmp16 >> 8; if (dev->adapter->dev_init) { err = dev->adapter->dev_init(dev); if (err) goto lbl_unregister_candev; } /* set bus off */ if (dev->adapter->dev_set_bus) { err = dev->adapter->dev_set_bus(dev, 0); if (err) goto lbl_unregister_candev; } /* get device number early */ if (dev->adapter->dev_get_device_id) dev->adapter->dev_get_device_id(dev, &dev->device_number); netdev_info(netdev, "attached to %s channel %u (device %u)\n", peak_usb_adapter->name, ctrl_idx, dev->device_number); return 0; lbl_unregister_candev: unregister_candev(netdev); lbl_restore_intf_data: usb_set_intfdata(intf, dev->prev_siblings); kfree(dev->cmd_buf); lbl_free_candev: free_candev(netdev); return err; } /* * called by the usb core when the device is unplugged from the system */ static void peak_usb_disconnect(struct usb_interface *intf) { struct peak_usb_device *dev; struct peak_usb_device *dev_prev_siblings; /* unregister as many netdev devices as siblings */ for (dev = usb_get_intfdata(intf); dev; dev = dev_prev_siblings) { struct net_device *netdev = dev->netdev; char name[IFNAMSIZ]; dev_prev_siblings = dev->prev_siblings; dev->state &= ~PCAN_USB_STATE_CONNECTED; strlcpy(name, netdev->name, IFNAMSIZ); unregister_netdev(netdev); kfree(dev->cmd_buf); dev->next_siblings = NULL; if (dev->adapter->dev_free) dev->adapter->dev_free(dev); free_candev(netdev); dev_info(&intf->dev, "%s removed\n", name); } usb_set_intfdata(intf, NULL); } /* * probe function for new PEAK-System devices */ static int peak_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct usb_device *usb_dev = interface_to_usbdev(intf); const u16 usb_id_product = le16_to_cpu(usb_dev->descriptor.idProduct); const struct peak_usb_adapter *peak_usb_adapter = NULL; int i, err = -ENOMEM; /* get corresponding PCAN-USB adapter */ for (i = 0; i < ARRAY_SIZE(peak_usb_adapters_list); i++) if (peak_usb_adapters_list[i]->device_id == usb_id_product) { peak_usb_adapter = peak_usb_adapters_list[i]; break; } if (!peak_usb_adapter) { /* should never come except device_id bad usage in this file */ pr_err("%s: didn't find device id. 0x%x in devices list\n", PCAN_USB_DRIVER_NAME, usb_id_product); return -ENODEV; } /* got corresponding adapter: check if it handles current interface */ if (peak_usb_adapter->intf_probe) { err = peak_usb_adapter->intf_probe(intf); if (err) return err; } for (i = 0; i < peak_usb_adapter->ctrl_count; i++) { err = peak_usb_create_dev(peak_usb_adapter, intf, i); if (err) { /* deregister already created devices */ peak_usb_disconnect(intf); break; } } return err; } /* usb specific object needed to register this driver with the usb subsystem */ static struct usb_driver peak_usb_driver = { .name = PCAN_USB_DRIVER_NAME, .disconnect = peak_usb_disconnect, .probe = peak_usb_probe, .id_table = peak_usb_table, }; static int __init peak_usb_init(void) { int err; /* register this driver with the USB subsystem */ err = usb_register(&peak_usb_driver); if (err) pr_err("%s: usb_register failed (err %d)\n", PCAN_USB_DRIVER_NAME, err); return err; } static int peak_usb_do_device_exit(struct device *d, void *arg) { struct usb_interface *intf = to_usb_interface(d); struct peak_usb_device *dev; /* stop as many netdev devices as siblings */ for (dev = usb_get_intfdata(intf); dev; dev = dev->prev_siblings) { struct net_device *netdev = dev->netdev; if (netif_device_present(netdev)) if (dev->adapter->dev_exit) dev->adapter->dev_exit(dev); } return 0; } static void __exit peak_usb_exit(void) { int err; /* last chance do send any synchronous commands here */ err = driver_for_each_device(&peak_usb_driver.drvwrap.driver, NULL, NULL, peak_usb_do_device_exit); if (err) pr_err("%s: failed to stop all can devices (err %d)\n", PCAN_USB_DRIVER_NAME, err); /* deregister this driver with the USB subsystem */ usb_deregister(&peak_usb_driver); pr_info("%s: PCAN-USB interfaces driver unloaded\n", PCAN_USB_DRIVER_NAME); } module_init(peak_usb_init); module_exit(peak_usb_exit);