diff options
Diffstat (limited to 'drivers/net/can/usb/gs_usb.c')
| -rw-r--r-- | drivers/net/can/usb/gs_usb.c | 971 |
1 files changed, 971 insertions, 0 deletions
diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c new file mode 100644 index 000000000000..04b0f84612f0 --- /dev/null +++ b/drivers/net/can/usb/gs_usb.c @@ -0,0 +1,971 @@ +/* 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 <linux/init.h> +#include <linux/signal.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <linux/usb.h> + +#include <linux/can.h> +#include <linux/can/dev.h> +#include <linux/can/error.h> + +/* 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, +}; + +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); + free_candev(dev->netdev); + usb_kill_anchored_urbs(&dev->tx_submitted); + kfree(dev); +} + +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); + 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])) { + /* on failure destroy previously created candevs */ + icount = i; + for (i = 0; i < icount; i++) { + gs_destroy_candev(dev->canch[i]); + dev->canch[i] = NULL; + } + 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++) { + struct gs_can *can = dev->canch[i]; + + if (!can) + continue; + + gs_destroy_candev(can); + } + + usb_kill_anchored_urbs(&dev->rx_submitted); +} + +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 <mws@schneidersoft.net>"); +MODULE_DESCRIPTION( +"Socket CAN device driver for Geschwister Schneider Technologie-, " +"Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces."); +MODULE_LICENSE("GPL v2"); |