/* CAN driver for Geschwister Schneider USB/CAN devices. * * Copyright (C) 2013 Geschwister Schneider Technologie-, * Entwicklungs- und Vertriebs UG (Haftungsbeschränkt). * * Many thanks to all socketcan devs! * * 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 /* Device specific constants */ #define USB_GSUSB_1_VENDOR_ID 0x1d50 #define USB_GSUSB_1_PRODUCT_ID 0x606f #define GSUSB_ENDPOINT_IN 1 #define GSUSB_ENDPOINT_OUT 2 /* Device specific constants */ enum gs_usb_breq { GS_USB_BREQ_HOST_FORMAT = 0, GS_USB_BREQ_BITTIMING, GS_USB_BREQ_MODE, GS_USB_BREQ_BERR, GS_USB_BREQ_BT_CONST, GS_USB_BREQ_DEVICE_CONFIG }; enum gs_can_mode { /* reset a channel. turns it off */ GS_CAN_MODE_RESET = 0, /* starts a channel */ GS_CAN_MODE_START }; enum gs_can_state { GS_CAN_STATE_ERROR_ACTIVE = 0, GS_CAN_STATE_ERROR_WARNING, GS_CAN_STATE_ERROR_PASSIVE, GS_CAN_STATE_BUS_OFF, GS_CAN_STATE_STOPPED, GS_CAN_STATE_SLEEPING }; /* data types passed between host and device */ struct gs_host_config { u32 byte_order; } __packed; /* All data exchanged between host and device is exchanged in host byte order, * thanks to the struct gs_host_config byte_order member, which is sent first * to indicate the desired byte order. */ struct gs_device_config { u8 reserved1; u8 reserved2; u8 reserved3; u8 icount; u32 sw_version; u32 hw_version; } __packed; #define GS_CAN_MODE_NORMAL 0 #define GS_CAN_MODE_LISTEN_ONLY (1<<0) #define GS_CAN_MODE_LOOP_BACK (1<<1) #define GS_CAN_MODE_TRIPLE_SAMPLE (1<<2) #define GS_CAN_MODE_ONE_SHOT (1<<3) struct gs_device_mode { u32 mode; u32 flags; } __packed; struct gs_device_state { u32 state; u32 rxerr; u32 txerr; } __packed; struct gs_device_bittiming { u32 prop_seg; u32 phase_seg1; u32 phase_seg2; u32 sjw; u32 brp; } __packed; #define GS_CAN_FEATURE_LISTEN_ONLY (1<<0) #define GS_CAN_FEATURE_LOOP_BACK (1<<1) #define GS_CAN_FEATURE_TRIPLE_SAMPLE (1<<2) #define GS_CAN_FEATURE_ONE_SHOT (1<<3) struct gs_device_bt_const { u32 feature; u32 fclk_can; u32 tseg1_min; u32 tseg1_max; u32 tseg2_min; u32 tseg2_max; u32 sjw_max; u32 brp_min; u32 brp_max; u32 brp_inc; } __packed; #define GS_CAN_FLAG_OVERFLOW 1 struct gs_host_frame { u32 echo_id; u32 can_id; u8 can_dlc; u8 channel; u8 flags; u8 reserved; u8 data[8]; } __packed; /* The GS USB devices make use of the same flags and masks as in * linux/can.h and linux/can/error.h, and no additional mapping is necessary. */ /* Only send a max of GS_MAX_TX_URBS frames per channel at a time. */ #define GS_MAX_TX_URBS 10 /* Only launch a max of GS_MAX_RX_URBS usb requests at a time. */ #define GS_MAX_RX_URBS 30 /* Maximum number of interfaces the driver supports per device. * Current hardware only supports 2 interfaces. The future may vary. */ #define GS_MAX_INTF 2 struct gs_tx_context { struct gs_can *dev; unsigned int echo_id; }; struct gs_can { struct can_priv can; /* must be the first member */ struct gs_usb *parent; struct net_device *netdev; struct usb_device *udev; struct usb_interface *iface; struct can_bittiming_const bt_const; unsigned int channel; /* channel number */ /* This lock prevents a race condition between xmit and recieve. */ spinlock_t tx_ctx_lock; struct gs_tx_context tx_context[GS_MAX_TX_URBS]; struct usb_anchor tx_submitted; atomic_t active_tx_urbs; }; /* usb interface struct */ struct gs_usb { struct gs_can *canch[GS_MAX_INTF]; struct usb_anchor rx_submitted; atomic_t active_channels; struct usb_device *udev; }; /* 'allocate' a tx context. * returns a valid tx context or NULL if there is no space. */ static struct gs_tx_context *gs_alloc_tx_context(struct gs_can *dev) { int i = 0; unsigned long flags; spin_lock_irqsave(&dev->tx_ctx_lock, flags); for (; i < GS_MAX_TX_URBS; i++) { if (dev->tx_context[i].echo_id == GS_MAX_TX_URBS) { dev->tx_context[i].echo_id = i; spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); return &dev->tx_context[i]; } } spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); return NULL; } /* releases a tx context */ static void gs_free_tx_context(struct gs_tx_context *txc) { txc->echo_id = GS_MAX_TX_URBS; } /* Get a tx context by id. */ static struct gs_tx_context *gs_get_tx_context(struct gs_can *dev, unsigned int id) { unsigned long flags; if (id < GS_MAX_TX_URBS) { spin_lock_irqsave(&dev->tx_ctx_lock, flags); if (dev->tx_context[id].echo_id == id) { spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); return &dev->tx_context[id]; } spin_unlock_irqrestore(&dev->tx_ctx_lock, flags); } return NULL; } static int gs_cmd_reset(struct gs_usb *gsusb, struct gs_can *gsdev) { struct gs_device_mode *dm; struct usb_interface *intf = gsdev->iface; int rc; dm = kzalloc(sizeof(*dm), GFP_KERNEL); if (!dm) return -ENOMEM; dm->mode = GS_CAN_MODE_RESET; rc = usb_control_msg(interface_to_usbdev(intf), usb_sndctrlpipe(interface_to_usbdev(intf), 0), GS_USB_BREQ_MODE, USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, gsdev->channel, 0, dm, sizeof(*dm), 1000); return rc; } static void gs_update_state(struct gs_can *dev, struct can_frame *cf) { struct can_device_stats *can_stats = &dev->can.can_stats; if (cf->can_id & CAN_ERR_RESTARTED) { dev->can.state = CAN_STATE_ERROR_ACTIVE; can_stats->restarts++; } else if (cf->can_id & CAN_ERR_BUSOFF) { dev->can.state = CAN_STATE_BUS_OFF; can_stats->bus_off++; } else if (cf->can_id & CAN_ERR_CRTL) { if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) || (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) { dev->can.state = CAN_STATE_ERROR_WARNING; can_stats->error_warning++; } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) || (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) { dev->can.state = CAN_STATE_ERROR_PASSIVE; can_stats->error_passive++; } else { dev->can.state = CAN_STATE_ERROR_ACTIVE; } } } static void gs_usb_recieve_bulk_callback(struct urb *urb) { struct gs_usb *usbcan = urb->context; struct gs_can *dev; struct net_device *netdev; int rc; struct net_device_stats *stats; struct gs_host_frame *hf = urb->transfer_buffer; struct gs_tx_context *txc; struct can_frame *cf; struct sk_buff *skb; BUG_ON(!usbcan); switch (urb->status) { case 0: /* success */ break; case -ENOENT: case -ESHUTDOWN: return; default: /* do not resubmit aborted urbs. eg: when device goes down */ return; } /* device reports out of range channel id */ if (hf->channel >= GS_MAX_INTF) goto resubmit_urb; dev = usbcan->canch[hf->channel]; netdev = dev->netdev; stats = &netdev->stats; if (!netif_device_present(netdev)) return; if (hf->echo_id == -1) { /* normal rx */ skb = alloc_can_skb(dev->netdev, &cf); if (!skb) return; cf->can_id = hf->can_id; cf->can_dlc = get_can_dlc(hf->can_dlc); memcpy(cf->data, hf->data, 8); /* ERROR frames tell us information about the controller */ if (hf->can_id & CAN_ERR_FLAG) gs_update_state(dev, cf); netdev->stats.rx_packets++; netdev->stats.rx_bytes += hf->can_dlc; netif_rx(skb); } else { /* echo_id == hf->echo_id */ if (hf->echo_id >= GS_MAX_TX_URBS) { netdev_err(netdev, "Unexpected out of range echo id %d\n", hf->echo_id); goto resubmit_urb; } netdev->stats.tx_packets++; netdev->stats.tx_bytes += hf->can_dlc; txc = gs_get_tx_context(dev, hf->echo_id); /* bad devices send bad echo_ids. */ if (!txc) { netdev_err(netdev, "Unexpected unused echo id %d\n", hf->echo_id); goto resubmit_urb; } can_get_echo_skb(netdev, hf->echo_id); gs_free_tx_context(txc); netif_wake_queue(netdev); } if (hf->flags & GS_CAN_FLAG_OVERFLOW) { skb = alloc_can_err_skb(netdev, &cf); if (!skb) goto resubmit_urb; cf->can_id |= CAN_ERR_CRTL; cf->can_dlc = CAN_ERR_DLC; cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; stats->rx_over_errors++; stats->rx_errors++; netif_rx(skb); } resubmit_urb: usb_fill_bulk_urb(urb, usbcan->udev, usb_rcvbulkpipe(usbcan->udev, GSUSB_ENDPOINT_IN), hf, sizeof(struct gs_host_frame), gs_usb_recieve_bulk_callback, usbcan ); rc = usb_submit_urb(urb, GFP_ATOMIC); /* USB failure take down all interfaces */ if (rc == -ENODEV) { for (rc = 0; rc < GS_MAX_INTF; rc++) { if (usbcan->canch[rc]) netif_device_detach(usbcan->canch[rc]->netdev); } } } static int gs_usb_set_bittiming(struct net_device *netdev) { struct gs_can *dev = netdev_priv(netdev); struct can_bittiming *bt = &dev->can.bittiming; struct usb_interface *intf = dev->iface; int rc; struct gs_device_bittiming *dbt; dbt = kmalloc(sizeof(*dbt), GFP_KERNEL); if (!dbt) return -ENOMEM; dbt->prop_seg = bt->prop_seg; dbt->phase_seg1 = bt->phase_seg1; dbt->phase_seg2 = bt->phase_seg2; dbt->sjw = bt->sjw; dbt->brp = bt->brp; /* request bit timings */ rc = usb_control_msg(interface_to_usbdev(intf), usb_sndctrlpipe(interface_to_usbdev(intf), 0), GS_USB_BREQ_BITTIMING, USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, dev->channel, 0, dbt, sizeof(*dbt), 1000); kfree(dbt); if (rc < 0) dev_err(netdev->dev.parent, "Couldn't set bittimings (err=%d)", rc); return rc; } static void gs_usb_xmit_callback(struct urb *urb) { struct gs_tx_context *txc = urb->context; struct gs_can *dev = txc->dev; struct net_device *netdev = dev->netdev; if (urb->status) netdev_info(netdev, "usb xmit fail %d\n", txc->echo_id); usb_free_coherent(urb->dev, urb->transfer_buffer_length, urb->transfer_buffer, urb->transfer_dma); atomic_dec(&dev->active_tx_urbs); if (!netif_device_present(netdev)) return; if (netif_queue_stopped(netdev)) netif_wake_queue(netdev); } static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb, struct net_device *netdev) { struct gs_can *dev = netdev_priv(netdev); struct net_device_stats *stats = &dev->netdev->stats; struct urb *urb; struct gs_host_frame *hf; struct can_frame *cf; int rc; unsigned int idx; struct gs_tx_context *txc; if (can_dropped_invalid_skb(netdev, skb)) return NETDEV_TX_OK; /* find an empty context to keep track of transmission */ txc = gs_alloc_tx_context(dev); if (!txc) return NETDEV_TX_BUSY; /* create a URB, and a buffer for it */ urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) { netdev_err(netdev, "No memory left for URB\n"); goto nomem_urb; } hf = usb_alloc_coherent(dev->udev, sizeof(*hf), GFP_ATOMIC, &urb->transfer_dma); if (!hf) { netdev_err(netdev, "No memory left for USB buffer\n"); goto nomem_hf; } idx = txc->echo_id; if (idx >= GS_MAX_TX_URBS) { netdev_err(netdev, "Invalid tx context %d\n", idx); goto badidx; } hf->echo_id = idx; hf->channel = dev->channel; cf = (struct can_frame *)skb->data; hf->can_id = cf->can_id; hf->can_dlc = cf->can_dlc; memcpy(hf->data, cf->data, cf->can_dlc); usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, GSUSB_ENDPOINT_OUT), hf, sizeof(*hf), gs_usb_xmit_callback, txc); urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; usb_anchor_urb(urb, &dev->tx_submitted); can_put_echo_skb(skb, netdev, idx); atomic_inc(&dev->active_tx_urbs); rc = usb_submit_urb(urb, GFP_ATOMIC); if (unlikely(rc)) { /* usb send failed */ atomic_dec(&dev->active_tx_urbs); can_free_echo_skb(netdev, idx); gs_free_tx_context(txc); usb_unanchor_urb(urb); usb_free_coherent(dev->udev, sizeof(*hf), hf, urb->transfer_dma); if (rc == -ENODEV) { netif_device_detach(netdev); } else { netdev_err(netdev, "usb_submit failed (err=%d)\n", rc); stats->tx_dropped++; } } else { /* Slow down tx path */ if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS) netif_stop_queue(netdev); } /* let usb core take care of this urb */ usb_free_urb(urb); return NETDEV_TX_OK; badidx: usb_free_coherent(dev->udev, sizeof(*hf), hf, urb->transfer_dma); nomem_hf: usb_free_urb(urb); nomem_urb: gs_free_tx_context(txc); dev_kfree_skb(skb); stats->tx_dropped++; return NETDEV_TX_OK; } static int gs_can_open(struct net_device *netdev) { struct gs_can *dev = netdev_priv(netdev); struct gs_usb *parent = dev->parent; int rc, i; struct gs_device_mode *dm; u32 ctrlmode; rc = open_candev(netdev); if (rc) return rc; if (atomic_add_return(1, &parent->active_channels) == 1) { for (i = 0; i < GS_MAX_RX_URBS; i++) { struct urb *urb; u8 *buf; /* alloc rx urb */ urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) { netdev_err(netdev, "No memory left for URB\n"); return -ENOMEM; } /* alloc rx buffer */ buf = usb_alloc_coherent(dev->udev, sizeof(struct gs_host_frame), GFP_KERNEL, &urb->transfer_dma); if (!buf) { netdev_err(netdev, "No memory left for USB buffer\n"); usb_free_urb(urb); return -ENOMEM; } /* fill, anchor, and submit rx urb */ usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, GSUSB_ENDPOINT_IN), buf, sizeof(struct gs_host_frame), gs_usb_recieve_bulk_callback, parent); urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; usb_anchor_urb(urb, &parent->rx_submitted); rc = usb_submit_urb(urb, GFP_KERNEL); if (rc) { if (rc == -ENODEV) netif_device_detach(dev->netdev); netdev_err(netdev, "usb_submit failed (err=%d)\n", rc); usb_unanchor_urb(urb); break; } /* Drop reference, * USB core will take care of freeing it */ usb_free_urb(urb); } } dm = kmalloc(sizeof(*dm), GFP_KERNEL); if (!dm) return -ENOMEM; /* flags */ ctrlmode = dev->can.ctrlmode; dm->flags = 0; if (ctrlmode & CAN_CTRLMODE_LOOPBACK) dm->flags |= GS_CAN_MODE_LOOP_BACK; else if (ctrlmode & CAN_CTRLMODE_LISTENONLY) dm->flags |= GS_CAN_MODE_LISTEN_ONLY; /* Controller is not allowed to retry TX * this mode is unavailable on atmels uc3c hardware */ if (ctrlmode & CAN_CTRLMODE_ONE_SHOT) dm->flags |= GS_CAN_MODE_ONE_SHOT; if (ctrlmode & CAN_CTRLMODE_3_SAMPLES) dm->flags |= GS_CAN_MODE_TRIPLE_SAMPLE; /* finally start device */ dm->mode = GS_CAN_MODE_START; rc = usb_control_msg(interface_to_usbdev(dev->iface), usb_sndctrlpipe(interface_to_usbdev(dev->iface), 0), GS_USB_BREQ_MODE, USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, dev->channel, 0, dm, sizeof(*dm), 1000); if (rc < 0) { netdev_err(netdev, "Couldn't start device (err=%d)\n", rc); kfree(dm); return rc; } kfree(dm); dev->can.state = CAN_STATE_ERROR_ACTIVE; if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)) netif_start_queue(netdev); return 0; } static int gs_can_close(struct net_device *netdev) { int rc; struct gs_can *dev = netdev_priv(netdev); struct gs_usb *parent = dev->parent; netif_stop_queue(netdev); /* Stop polling */ if (atomic_dec_and_test(&parent->active_channels)) usb_kill_anchored_urbs(&parent->rx_submitted); /* Stop sending URBs */ usb_kill_anchored_urbs(&dev->tx_submitted); atomic_set(&dev->active_tx_urbs, 0); /* reset the device */ rc = gs_cmd_reset(parent, dev); if (rc < 0) netdev_warn(netdev, "Couldn't shutdown device (err=%d)", rc); /* reset tx contexts */ for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { dev->tx_context[rc].dev = dev; dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; } /* close the netdev */ close_candev(netdev); return 0; } static const struct net_device_ops gs_usb_netdev_ops = { .ndo_open = gs_can_open, .ndo_stop = gs_can_close, .ndo_start_xmit = gs_can_start_xmit, .ndo_change_mtu = can_change_mtu, }; static struct gs_can *gs_make_candev(unsigned int channel, struct usb_interface *intf) { struct gs_can *dev; struct net_device *netdev; int rc; struct gs_device_bt_const *bt_const; bt_const = kmalloc(sizeof(*bt_const), GFP_KERNEL); if (!bt_const) return ERR_PTR(-ENOMEM); /* fetch bit timing constants */ rc = usb_control_msg(interface_to_usbdev(intf), usb_rcvctrlpipe(interface_to_usbdev(intf), 0), GS_USB_BREQ_BT_CONST, USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, channel, 0, bt_const, sizeof(*bt_const), 1000); if (rc < 0) { dev_err(&intf->dev, "Couldn't get bit timing const for channel (err=%d)\n", rc); kfree(bt_const); return ERR_PTR(rc); } /* create netdev */ netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS); if (!netdev) { dev_err(&intf->dev, "Couldn't allocate candev\n"); kfree(bt_const); return ERR_PTR(-ENOMEM); } dev = netdev_priv(netdev); netdev->netdev_ops = &gs_usb_netdev_ops; netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */ /* dev settup */ strcpy(dev->bt_const.name, "gs_usb"); dev->bt_const.tseg1_min = bt_const->tseg1_min; dev->bt_const.tseg1_max = bt_const->tseg1_max; dev->bt_const.tseg2_min = bt_const->tseg2_min; dev->bt_const.tseg2_max = bt_const->tseg2_max; dev->bt_const.sjw_max = bt_const->sjw_max; dev->bt_const.brp_min = bt_const->brp_min; dev->bt_const.brp_max = bt_const->brp_max; dev->bt_const.brp_inc = bt_const->brp_inc; dev->udev = interface_to_usbdev(intf); dev->iface = intf; dev->netdev = netdev; dev->channel = channel; init_usb_anchor(&dev->tx_submitted); atomic_set(&dev->active_tx_urbs, 0); spin_lock_init(&dev->tx_ctx_lock); for (rc = 0; rc < GS_MAX_TX_URBS; rc++) { dev->tx_context[rc].dev = dev; dev->tx_context[rc].echo_id = GS_MAX_TX_URBS; } /* can settup */ dev->can.state = CAN_STATE_STOPPED; dev->can.clock.freq = bt_const->fclk_can; dev->can.bittiming_const = &dev->bt_const; dev->can.do_set_bittiming = gs_usb_set_bittiming; dev->can.ctrlmode_supported = 0; if (bt_const->feature & GS_CAN_FEATURE_LISTEN_ONLY) dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY; if (bt_const->feature & GS_CAN_FEATURE_LOOP_BACK) dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK; if (bt_const->feature & GS_CAN_FEATURE_TRIPLE_SAMPLE) dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES; if (bt_const->feature & GS_CAN_FEATURE_ONE_SHOT) dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT; kfree(bt_const); SET_NETDEV_DEV(netdev, &intf->dev); rc = register_candev(dev->netdev); if (rc) { free_candev(dev->netdev); dev_err(&intf->dev, "Couldn't register candev (err=%d)\n", rc); return ERR_PTR(rc); } return dev; } static void gs_destroy_candev(struct gs_can *dev) { unregister_candev(dev->netdev); usb_kill_anchored_urbs(&dev->tx_submitted); free_candev(dev->netdev); } static int gs_usb_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct gs_usb *dev; int rc = -ENOMEM; unsigned int icount, i; struct gs_host_config *hconf; struct gs_device_config *dconf; hconf = kmalloc(sizeof(*hconf), GFP_KERNEL); if (!hconf) return -ENOMEM; hconf->byte_order = 0x0000beef; /* send host config */ rc = usb_control_msg(interface_to_usbdev(intf), usb_sndctrlpipe(interface_to_usbdev(intf), 0), GS_USB_BREQ_HOST_FORMAT, USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 1, intf->altsetting[0].desc.bInterfaceNumber, hconf, sizeof(*hconf), 1000); kfree(hconf); if (rc < 0) { dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", rc); return rc; } dconf = kmalloc(sizeof(*dconf), GFP_KERNEL); if (!dconf) return -ENOMEM; /* read device config */ rc = usb_control_msg(interface_to_usbdev(intf), usb_rcvctrlpipe(interface_to_usbdev(intf), 0), GS_USB_BREQ_DEVICE_CONFIG, USB_DIR_IN|USB_TYPE_VENDOR|USB_RECIP_INTERFACE, 1, intf->altsetting[0].desc.bInterfaceNumber, dconf, sizeof(*dconf), 1000); if (rc < 0) { dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n", rc); kfree(dconf); return rc; } icount = dconf->icount+1; kfree(dconf); dev_info(&intf->dev, "Configuring for %d interfaces\n", icount); if (icount > GS_MAX_INTF) { dev_err(&intf->dev, "Driver cannot handle more that %d CAN interfaces\n", GS_MAX_INTF); return -EINVAL; } dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (!dev) return -ENOMEM; init_usb_anchor(&dev->rx_submitted); atomic_set(&dev->active_channels, 0); usb_set_intfdata(intf, dev); dev->udev = interface_to_usbdev(intf); for (i = 0; i < icount; i++) { dev->canch[i] = gs_make_candev(i, intf); if (IS_ERR_OR_NULL(dev->canch[i])) { /* save error code to return later */ rc = PTR_ERR(dev->canch[i]); /* on failure destroy previously created candevs */ icount = i; for (i = 0; i < icount; i++) gs_destroy_candev(dev->canch[i]); usb_kill_anchored_urbs(&dev->rx_submitted); kfree(dev); return rc; } dev->canch[i]->parent = dev; } return 0; } static void gs_usb_disconnect(struct usb_interface *intf) { unsigned i; struct gs_usb *dev = usb_get_intfdata(intf); usb_set_intfdata(intf, NULL); if (!dev) { dev_err(&intf->dev, "Disconnect (nodata)\n"); return; } for (i = 0; i < GS_MAX_INTF; i++) if (dev->canch[i]) gs_destroy_candev(dev->canch[i]); usb_kill_anchored_urbs(&dev->rx_submitted); kfree(dev); } static const struct usb_device_id gs_usb_table[] = { {USB_DEVICE(USB_GSUSB_1_VENDOR_ID, USB_GSUSB_1_PRODUCT_ID)}, {} /* Terminating entry */ }; MODULE_DEVICE_TABLE(usb, gs_usb_table); static struct usb_driver gs_usb_driver = { .name = "gs_usb", .probe = gs_usb_probe, .disconnect = gs_usb_disconnect, .id_table = gs_usb_table, }; module_usb_driver(gs_usb_driver); MODULE_AUTHOR("Maximilian Schneider "); MODULE_DESCRIPTION( "Socket CAN device driver for Geschwister Schneider Technologie-, " "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces."); MODULE_LICENSE("GPL v2");