/* Let priv->eskbp catch up to regs->txrd and echo back the skbs if echo * is true and free them otherwise. * * If budget is >= 0, stop after handling at most budget skbs. Otherwise, * continue until priv->eskbp catches up to regs->txrd. * * priv->lock *must* be held when calling this function */ static int catch_up_echo_skb(struct net_device *dev, int budget, bool echo) { struct grcan_priv *priv = netdev_priv(dev); struct grcan_registers __iomem *regs = priv->regs; struct grcan_dma *dma = &priv->dma; struct net_device_stats *stats = &dev->stats; int i, work_done; /* Updates to priv->eskbp and wake-ups of the queue needs to * be atomic towards the reads of priv->eskbp and shut-downs * of the queue in grcan_start_xmit. */ u32 txrd = grcan_read_reg(®s->txrd); for (work_done = 0; work_done < budget || budget < 0; work_done++) { if (priv->eskbp == txrd) break; i = priv->eskbp / GRCAN_MSG_SIZE; if (echo) { /* Normal echo of messages */ stats->tx_packets++; stats->tx_bytes += priv->txdlc[i]; priv->txdlc[i] = 0; can_get_echo_skb(dev, i); } else { /* For cleanup of untransmitted messages */ can_free_echo_skb(dev, i); } priv->eskbp = grcan_ring_add(priv->eskbp, GRCAN_MSG_SIZE, dma->tx.size); txrd = grcan_read_reg(®s->txrd); } return work_done; }
irqreturn_t omapl_tx_can_intr(int irq, void *dev_id) { struct net_device *ndev = dev_id; struct omapl_pru_can_priv *priv = netdev_priv(ndev); struct net_device_stats *stats = &ndev->stats; u32 bit_set, mbxno; pru_can_get_interrupt_status(&priv->can_tx_hndl); if ((PRU_CAN_ISR_BIT_CCI & priv->can_tx_hndl.u32interruptstatus) || (PRU_CAN_ISR_BIT_SRDI & priv->can_tx_hndl.u32interruptstatus)) { __can_debug("tx_int_status = 0x%X\n", priv->can_tx_hndl.u32interruptstatus); can_free_echo_skb(ndev, 0); } else { for (bit_set = 0; ((priv->can_tx_hndl.u32interruptstatus & 0xFF) >> bit_set != 0); bit_set++) ; if (0 == bit_set) { __can_err("%s: invalid mailbox number\n", __func__); can_free_echo_skb(ndev, 0); } else { mbxno = bit_set - 1; /* mail box numbering starts from 0 */ if (PRU_CAN_ISR_BIT_ESI & priv->can_tx_hndl. u32interruptstatus) { /* read gsr and ack pru */ pru_can_get_global_status(&priv->can_tx_hndl); omapl_pru_can_err(ndev, priv->can_tx_hndl. u32interruptstatus, priv->can_tx_hndl. u32globalstatus); } else { stats->tx_packets++; /* stats->tx_bytes += dlc; */ //can_//get_echo_skb(ndev, 0); } } } if (netif_queue_stopped(ndev)) netif_wake_queue(ndev); can_get_echo_skb(ndev, 0); pru_can_transfer_mode_set(true, ecanreceive); return IRQ_HANDLED; }
static void mcp251x_clean(struct net_device *net) { struct mcp251x_priv *priv = netdev_priv(net); if (priv->tx_skb || priv->tx_len) net->stats.tx_errors++; if (priv->tx_skb) dev_kfree_skb(priv->tx_skb); if (priv->tx_len) can_free_echo_skb(priv->net, 0); priv->tx_skb = NULL; priv->tx_len = 0; }
/* Send close command to device */ static int usb_8dev_cmd_close(struct usb_8dev_priv *priv) { struct usb_8dev_cmd_msg inmsg; struct usb_8dev_cmd_msg outmsg = { .channel = 0, .command = USB_8DEV_CLOSE, .opt1 = 0, .opt2 = 0 }; return usb_8dev_send_cmd(priv, &outmsg, &inmsg); } /* Get firmware and hardware version */ static int usb_8dev_cmd_version(struct usb_8dev_priv *priv, u32 *res) { struct usb_8dev_cmd_msg inmsg; struct usb_8dev_cmd_msg outmsg = { .channel = 0, .command = USB_8DEV_GET_SOFTW_HARDW_VER, .opt1 = 0, .opt2 = 0 }; int err = usb_8dev_send_cmd(priv, &outmsg, &inmsg); if (err) return err; *res = be32_to_cpup((__be32 *)inmsg.data); return err; } /* Set network device mode * * Maybe we should leave this function empty, because the device * set mode variable with open command. */ static int usb_8dev_set_mode(struct net_device *netdev, enum can_mode mode) { struct usb_8dev_priv *priv = netdev_priv(netdev); int err = 0; switch (mode) { case CAN_MODE_START: err = usb_8dev_cmd_open(priv); if (err) netdev_warn(netdev, "couldn't start device"); break; default: return -EOPNOTSUPP; } return err; } /* Read error/status frames */ static void usb_8dev_rx_err_msg(struct usb_8dev_priv *priv, struct usb_8dev_rx_msg *msg) { struct can_frame *cf; struct sk_buff *skb; struct net_device_stats *stats = &priv->netdev->stats; /* Error message: * byte 0: Status * byte 1: bit 7: Receive Passive * byte 1: bit 0-6: Receive Error Counter * byte 2: Transmit Error Counter * byte 3: Always 0 (maybe reserved for future use) */ u8 state = msg->data[0]; u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK; u8 txerr = msg->data[2]; int rx_errors = 0; int tx_errors = 0; skb = alloc_can_err_skb(priv->netdev, &cf); if (!skb) return; switch (state) { case USB_8DEV_STATUSMSG_OK: priv->can.state = CAN_STATE_ERROR_ACTIVE; cf->can_id |= CAN_ERR_PROT; cf->data[2] = CAN_ERR_PROT_ACTIVE; break; case USB_8DEV_STATUSMSG_BUSOFF: priv->can.state = CAN_STATE_BUS_OFF; cf->can_id |= CAN_ERR_BUSOFF; can_bus_off(priv->netdev); break; case USB_8DEV_STATUSMSG_OVERRUN: case USB_8DEV_STATUSMSG_BUSLIGHT: case USB_8DEV_STATUSMSG_BUSHEAVY: cf->can_id |= CAN_ERR_CRTL; break; default: priv->can.state = CAN_STATE_ERROR_WARNING; cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR; priv->can.can_stats.bus_error++; break; } switch (state) { case USB_8DEV_STATUSMSG_OK: case USB_8DEV_STATUSMSG_BUSOFF: break; case USB_8DEV_STATUSMSG_ACK: cf->can_id |= CAN_ERR_ACK; tx_errors = 1; break; case USB_8DEV_STATUSMSG_CRC: cf->data[2] |= CAN_ERR_PROT_UNSPEC; cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ | CAN_ERR_PROT_LOC_CRC_DEL; rx_errors = 1; break; case USB_8DEV_STATUSMSG_BIT0: cf->data[2] |= CAN_ERR_PROT_BIT0; tx_errors = 1; break; case USB_8DEV_STATUSMSG_BIT1: cf->data[2] |= CAN_ERR_PROT_BIT1; tx_errors = 1; break; case USB_8DEV_STATUSMSG_FORM: cf->data[2] |= CAN_ERR_PROT_FORM; rx_errors = 1; break; case USB_8DEV_STATUSMSG_STUFF: cf->data[2] |= CAN_ERR_PROT_STUFF; rx_errors = 1; break; case USB_8DEV_STATUSMSG_OVERRUN: cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW; stats->rx_over_errors++; rx_errors = 1; break; case USB_8DEV_STATUSMSG_BUSLIGHT: priv->can.state = CAN_STATE_ERROR_WARNING; cf->data[1] = (txerr > rxerr) ? CAN_ERR_CRTL_TX_WARNING : CAN_ERR_CRTL_RX_WARNING; priv->can.can_stats.error_warning++; break; case USB_8DEV_STATUSMSG_BUSHEAVY: priv->can.state = CAN_STATE_ERROR_PASSIVE; cf->data[1] = (txerr > rxerr) ? CAN_ERR_CRTL_TX_PASSIVE : CAN_ERR_CRTL_RX_PASSIVE; priv->can.can_stats.error_passive++; break; default: netdev_warn(priv->netdev, "Unknown status/error message (%d)\n", state); break; } if (tx_errors) { cf->data[2] |= CAN_ERR_PROT_TX; stats->tx_errors++; } if (rx_errors) stats->rx_errors++; cf->data[6] = txerr; cf->data[7] = rxerr; priv->bec.txerr = txerr; priv->bec.rxerr = rxerr; netif_rx(skb); stats->rx_packets++; stats->rx_bytes += cf->can_dlc; } /* Read data and status frames */ static void usb_8dev_rx_can_msg(struct usb_8dev_priv *priv, struct usb_8dev_rx_msg *msg) { struct can_frame *cf; struct sk_buff *skb; struct net_device_stats *stats = &priv->netdev->stats; if (msg->type == USB_8DEV_TYPE_ERROR_FRAME && msg->flags == USB_8DEV_ERR_FLAG) { usb_8dev_rx_err_msg(priv, msg); } else if (msg->type == USB_8DEV_TYPE_CAN_FRAME) { skb = alloc_can_skb(priv->netdev, &cf); if (!skb) return; cf->can_id = be32_to_cpu(msg->id); cf->can_dlc = get_can_dlc(msg->dlc & 0xF); if (msg->flags & USB_8DEV_EXTID) cf->can_id |= CAN_EFF_FLAG; if (msg->flags & USB_8DEV_RTR) cf->can_id |= CAN_RTR_FLAG; else memcpy(cf->data, msg->data, cf->can_dlc); netif_rx(skb); stats->rx_packets++; stats->rx_bytes += cf->can_dlc; can_led_event(priv->netdev, CAN_LED_EVENT_RX); } else { netdev_warn(priv->netdev, "frame type %d unknown", msg->type); } } /* Callback for reading data from device * * Check urb status, call read function and resubmit urb read operation. */ static void usb_8dev_read_bulk_callback(struct urb *urb) { struct usb_8dev_priv *priv = urb->context; struct net_device *netdev; int retval; int pos = 0; netdev = priv->netdev; if (!netif_device_present(netdev)) return; switch (urb->status) { case 0: /* success */ break; case -ENOENT: case -ESHUTDOWN: return; default: netdev_info(netdev, "Rx URB aborted (%d)\n", urb->status); goto resubmit_urb; } while (pos < urb->actual_length) { struct usb_8dev_rx_msg *msg; if (pos + sizeof(struct usb_8dev_rx_msg) > urb->actual_length) { netdev_err(priv->netdev, "format error\n"); break; } msg = (struct usb_8dev_rx_msg *)(urb->transfer_buffer + pos); usb_8dev_rx_can_msg(priv, msg); pos += sizeof(struct usb_8dev_rx_msg); } resubmit_urb: usb_fill_bulk_urb(urb, priv->udev, usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX), urb->transfer_buffer, RX_BUFFER_SIZE, usb_8dev_read_bulk_callback, priv); retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval == -ENODEV) netif_device_detach(netdev); else if (retval) netdev_err(netdev, "failed resubmitting read bulk urb: %d\n", retval); } /* Callback handler for write operations * * Free allocated buffers, check transmit status and * calculate statistic. */ static void usb_8dev_write_bulk_callback(struct urb *urb) { struct usb_8dev_tx_urb_context *context = urb->context; struct usb_8dev_priv *priv; struct net_device *netdev; BUG_ON(!context); priv = context->priv; netdev = priv->netdev; /* free up our allocated buffer */ usb_free_coherent(urb->dev, urb->transfer_buffer_length, urb->transfer_buffer, urb->transfer_dma); atomic_dec(&priv->active_tx_urbs); if (!netif_device_present(netdev)) return; if (urb->status) netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status); netdev->stats.tx_packets++; netdev->stats.tx_bytes += context->dlc; can_get_echo_skb(netdev, context->echo_index); can_led_event(netdev, CAN_LED_EVENT_TX); /* Release context */ context->echo_index = MAX_TX_URBS; netif_wake_queue(netdev); } /* Send data to device */ static netdev_tx_t usb_8dev_start_xmit(struct sk_buff *skb, struct net_device *netdev) { struct usb_8dev_priv *priv = netdev_priv(netdev); struct net_device_stats *stats = &netdev->stats; struct can_frame *cf = (struct can_frame *) skb->data; struct usb_8dev_tx_msg *msg; struct urb *urb; struct usb_8dev_tx_urb_context *context = NULL; u8 *buf; int i, err; size_t size = sizeof(struct usb_8dev_tx_msg); if (can_dropped_invalid_skb(netdev, skb)) return NETDEV_TX_OK; /* create a URB, and a buffer for it, and copy the data to the URB */ urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) { netdev_err(netdev, "No memory left for URBs\n"); goto nomem; } buf = usb_alloc_coherent(priv->udev, size, GFP_ATOMIC, &urb->transfer_dma); if (!buf) { netdev_err(netdev, "No memory left for USB buffer\n"); goto nomembuf; } memset(buf, 0, size); msg = (struct usb_8dev_tx_msg *)buf; msg->begin = USB_8DEV_DATA_START; msg->flags = 0x00; if (cf->can_id & CAN_RTR_FLAG) msg->flags |= USB_8DEV_RTR; if (cf->can_id & CAN_EFF_FLAG) msg->flags |= USB_8DEV_EXTID; msg->id = cpu_to_be32(cf->can_id & CAN_ERR_MASK); msg->dlc = cf->can_dlc; memcpy(msg->data, cf->data, cf->can_dlc); msg->end = USB_8DEV_DATA_END; for (i = 0; i < MAX_TX_URBS; i++) { if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) { context = &priv->tx_contexts[i]; break; } } /* May never happen! When this happens we'd more URBs in flight as * allowed (MAX_TX_URBS). */ if (!context) goto nofreecontext; context->priv = priv; context->echo_index = i; context->dlc = cf->can_dlc; usb_fill_bulk_urb(urb, priv->udev, usb_sndbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_TX), buf, size, usb_8dev_write_bulk_callback, context); urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; usb_anchor_urb(urb, &priv->tx_submitted); can_put_echo_skb(skb, netdev, context->echo_index); atomic_inc(&priv->active_tx_urbs); err = usb_submit_urb(urb, GFP_ATOMIC); if (unlikely(err)) goto failed; else if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) /* Slow down tx path */ netif_stop_queue(netdev); /* Release our reference to this URB, the USB core will eventually free * it entirely. */ usb_free_urb(urb); return NETDEV_TX_OK; nofreecontext: usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); usb_free_urb(urb); netdev_warn(netdev, "couldn't find free context"); return NETDEV_TX_BUSY; failed: can_free_echo_skb(netdev, context->echo_index); usb_unanchor_urb(urb); usb_free_coherent(priv->udev, size, buf, urb->transfer_dma); atomic_dec(&priv->active_tx_urbs); if (err == -ENODEV) netif_device_detach(netdev); else netdev_warn(netdev, "failed tx_urb %d\n", err); nomembuf: usb_free_urb(urb); nomem: dev_kfree_skb(skb); stats->tx_dropped++; return NETDEV_TX_OK; } static int usb_8dev_get_berr_counter(const struct net_device *netdev, struct can_berr_counter *bec) { struct usb_8dev_priv *priv = netdev_priv(netdev); bec->txerr = priv->bec.txerr; bec->rxerr = priv->bec.rxerr; return 0; } /* Start USB device */ static int usb_8dev_start(struct usb_8dev_priv *priv) { struct net_device *netdev = priv->netdev; int err, i; for (i = 0; i < MAX_RX_URBS; i++) { struct urb *urb = NULL; u8 *buf; /* create a URB, and a buffer for it */ urb = usb_alloc_urb(0, GFP_KERNEL); if (!urb) { netdev_err(netdev, "No memory left for URBs\n"); err = -ENOMEM; break; } buf = usb_alloc_coherent(priv->udev, RX_BUFFER_SIZE, GFP_KERNEL, &urb->transfer_dma); if (!buf) { netdev_err(netdev, "No memory left for USB buffer\n"); usb_free_urb(urb); err = -ENOMEM; break; } usb_fill_bulk_urb(urb, priv->udev, usb_rcvbulkpipe(priv->udev, USB_8DEV_ENDP_DATA_RX), buf, RX_BUFFER_SIZE, usb_8dev_read_bulk_callback, priv); urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; usb_anchor_urb(urb, &priv->rx_submitted); err = usb_submit_urb(urb, GFP_KERNEL); if (err) { usb_unanchor_urb(urb); usb_free_coherent(priv->udev, RX_BUFFER_SIZE, buf, urb->transfer_dma); usb_free_urb(urb); break; } /* Drop reference, USB core will take care of freeing it */ usb_free_urb(urb); } /* Did we submit any URBs */ if (i == 0) { netdev_warn(netdev, "couldn't setup read URBs\n"); return err; } /* Warn if we've couldn't transmit all the URBs */ if (i < MAX_RX_URBS) netdev_warn(netdev, "rx performance may be slow\n"); err = usb_8dev_cmd_open(priv); if (err) goto failed; priv->can.state = CAN_STATE_ERROR_ACTIVE; return 0; failed: if (err == -ENODEV) netif_device_detach(priv->netdev); netdev_warn(netdev, "couldn't submit control: %d\n", err); return err; } /* Open USB device */ static int usb_8dev_open(struct net_device *netdev) { struct usb_8dev_priv *priv = netdev_priv(netdev); int err; /* common open */ err = open_candev(netdev); if (err) return err; can_led_event(netdev, CAN_LED_EVENT_OPEN); /* finally start device */ err = usb_8dev_start(priv); if (err) { if (err == -ENODEV) netif_device_detach(priv->netdev); netdev_warn(netdev, "couldn't start device: %d\n", err); close_candev(netdev); return err; } netif_start_queue(netdev); return 0; } static void unlink_all_urbs(struct usb_8dev_priv *priv) { int i; usb_kill_anchored_urbs(&priv->rx_submitted); usb_kill_anchored_urbs(&priv->tx_submitted); atomic_set(&priv->active_tx_urbs, 0); for (i = 0; i < MAX_TX_URBS; i++) priv->tx_contexts[i].echo_index = MAX_TX_URBS; } /* Close USB device */ static int usb_8dev_close(struct net_device *netdev) { struct usb_8dev_priv *priv = netdev_priv(netdev); int err = 0; /* Send CLOSE command to CAN controller */ err = usb_8dev_cmd_close(priv); if (err) netdev_warn(netdev, "couldn't stop device"); priv->can.state = CAN_STATE_STOPPED; netif_stop_queue(netdev); /* Stop polling */ unlink_all_urbs(priv); close_candev(netdev); can_led_event(netdev, CAN_LED_EVENT_STOP); return err; } static const struct net_device_ops usb_8dev_netdev_ops = { .ndo_open = usb_8dev_open, .ndo_stop = usb_8dev_close, .ndo_start_xmit = usb_8dev_start_xmit, .ndo_change_mtu = can_change_mtu, }; static const struct can_bittiming_const usb_8dev_bittiming_const = { .name = "usb_8dev", .tseg1_min = 1, .tseg1_max = 16, .tseg2_min = 1, .tseg2_max = 8, .sjw_max = 4, .brp_min = 1, .brp_max = 1024, .brp_inc = 1, }; /* Probe USB device * * Check device and firmware. * Set supported modes and bittiming constants. * Allocate some memory. */ static int usb_8dev_probe(struct usb_interface *intf, const struct usb_device_id *id) { struct net_device *netdev; struct usb_8dev_priv *priv; int i, err = -ENOMEM; u32 version; char buf[18]; struct usb_device *usbdev = interface_to_usbdev(intf); /* product id looks strange, better we also check iProduct string */ if (usb_string(usbdev, usbdev->descriptor.iProduct, buf, sizeof(buf)) > 0 && strcmp(buf, "USB2CAN converter")) { dev_info(&usbdev->dev, "ignoring: not an USB2CAN converter\n"); return -ENODEV; } netdev = alloc_candev(sizeof(struct usb_8dev_priv), MAX_TX_URBS); if (!netdev) { dev_err(&intf->dev, "Couldn't alloc candev\n"); return -ENOMEM; } priv = netdev_priv(netdev); priv->udev = usbdev; priv->netdev = netdev; priv->can.state = CAN_STATE_STOPPED; priv->can.clock.freq = USB_8DEV_ABP_CLOCK; priv->can.bittiming_const = &usb_8dev_bittiming_const; priv->can.do_set_mode = usb_8dev_set_mode; priv->can.do_get_berr_counter = usb_8dev_get_berr_counter; priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_ONE_SHOT; netdev->netdev_ops = &usb_8dev_netdev_ops; netdev->flags |= IFF_ECHO; /* we support local echo */ init_usb_anchor(&priv->rx_submitted); init_usb_anchor(&priv->tx_submitted); atomic_set(&priv->active_tx_urbs, 0); for (i = 0; i < MAX_TX_URBS; i++) priv->tx_contexts[i].echo_index = MAX_TX_URBS; priv->cmd_msg_buffer = kzalloc(sizeof(struct usb_8dev_cmd_msg), GFP_KERNEL); if (!priv->cmd_msg_buffer) goto cleanup_candev; usb_set_intfdata(intf, priv); SET_NETDEV_DEV(netdev, &intf->dev); mutex_init(&priv->usb_8dev_cmd_lock); err = register_candev(netdev); if (err) { netdev_err(netdev, "couldn't register CAN device: %d\n", err); goto cleanup_cmd_msg_buffer; } err = usb_8dev_cmd_version(priv, &version); if (err) { netdev_err(netdev, "can't get firmware version\n"); goto cleanup_unregister_candev; } else { netdev_info(netdev, "firmware: %d.%d, hardware: %d.%d\n", (version>>24) & 0xff, (version>>16) & 0xff, (version>>8) & 0xff, version & 0xff); } devm_can_led_init(netdev); return 0; cleanup_unregister_candev: unregister_netdev(priv->netdev); cleanup_cmd_msg_buffer: kfree(priv->cmd_msg_buffer); cleanup_candev: free_candev(netdev); return err; } /* Called by the usb core when driver is unloaded or device is removed */ static void usb_8dev_disconnect(struct usb_interface *intf) { struct usb_8dev_priv *priv = usb_get_intfdata(intf); usb_set_intfdata(intf, NULL); if (priv) { netdev_info(priv->netdev, "device disconnected\n"); unregister_netdev(priv->netdev); free_candev(priv->netdev); unlink_all_urbs(priv); } } static struct usb_driver usb_8dev_driver = { .name = "usb_8dev", .probe = usb_8dev_probe, .disconnect = usb_8dev_disconnect, .id_table = usb_8dev_table, }; module_usb_driver(usb_8dev_driver); MODULE_AUTHOR("Bernd Krumboeck <*****@*****.**>"); MODULE_DESCRIPTION("CAN driver for 8 devices USB2CAN interfaces"); MODULE_LICENSE("GPL v2");
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) 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 netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *netdev) { struct ems_usb *dev = netdev_priv(netdev); struct ems_tx_urb_context *context = NULL; struct net_device_stats *stats = &netdev->stats; struct can_frame *cf = (struct can_frame *)skb->data; struct ems_cpc_msg *msg; struct urb *urb; u8 *buf; int i, err; size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN + sizeof(struct cpc_can_msg); if (can_dropped_invalid_skb(netdev, skb)) return NETDEV_TX_OK; /* create a URB, and a buffer for it, and copy the data to the URB */ urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) { netdev_err(netdev, "No memory left for URBs\n"); goto nomem; } buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC, &urb->transfer_dma); if (!buf) { netdev_err(netdev, "No memory left for USB buffer\n"); usb_free_urb(urb); goto nomem; } msg = (struct ems_cpc_msg *)&buf[CPC_HEADER_SIZE]; msg->msg.can_msg.id = cf->can_id & CAN_ERR_MASK; msg->msg.can_msg.length = cf->can_dlc; if (cf->can_id & CAN_RTR_FLAG) { msg->type = cf->can_id & CAN_EFF_FLAG ? CPC_CMD_TYPE_EXT_RTR_FRAME : CPC_CMD_TYPE_RTR_FRAME; msg->length = CPC_CAN_MSG_MIN_SIZE; } else { msg->type = cf->can_id & CAN_EFF_FLAG ? CPC_CMD_TYPE_EXT_CAN_FRAME : CPC_CMD_TYPE_CAN_FRAME; for (i = 0; i < cf->can_dlc; i++) msg->msg.can_msg.msg[i] = cf->data[i]; msg->length = CPC_CAN_MSG_MIN_SIZE + cf->can_dlc; } /* Respect byte order */ msg->msg.can_msg.id = cpu_to_le32(msg->msg.can_msg.id); for (i = 0; i < MAX_TX_URBS; i++) { if (dev->tx_contexts[i].echo_index == MAX_TX_URBS) { context = &dev->tx_contexts[i]; break; } } /* * May never happen! When this happens we'd more URBs in flight as * allowed (MAX_TX_URBS). */ if (!context) { usb_free_coherent(dev->udev, size, buf, urb->transfer_dma); usb_free_urb(urb); netdev_warn(netdev, "couldn't find free context\n"); return NETDEV_TX_BUSY; } context->dev = dev; context->echo_index = i; context->dlc = cf->can_dlc; usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf, size, ems_usb_write_bulk_callback, context); urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP; 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 (unlikely(err)) { can_free_echo_skb(netdev, context->echo_index); usb_unanchor_urb(urb); usb_free_coherent(dev->udev, size, buf, urb->transfer_dma); dev_kfree_skb(skb); atomic_dec(&dev->active_tx_urbs); if (err == -ENODEV) { netif_device_detach(netdev); } else { netdev_warn(netdev, "failed tx_urb %d\n", err); stats->tx_dropped++; } } else { netdev->trans_start = jiffies; /* Slow down tx path */ if (atomic_read(&dev->active_tx_urbs) >= MAX_TX_URBS || dev->free_slots < 5) { netif_stop_queue(netdev); } } /* * Release our reference to this URB, the USB core will eventually free * it entirely. */ usb_free_urb(urb); return NETDEV_TX_OK; nomem: dev_kfree_skb(skb); stats->tx_dropped++; return NETDEV_TX_OK; }