/* * USB Network driver infrastructure * Copyright (C) 2000-2005 by David Brownell * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com> * * 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; either version 2 of the License, or * (at your option) any later version. * * 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. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* * This is a generic "USB networking" framework that works with several * kinds of full and high speed networking devices: host-to-host cables, * smart usb peripherals, and actual Ethernet adapters. * * These devices usually differ in terms of control protocols (if they * even have one!) and sometimes they define new framing to wrap or batch * Ethernet packets. Otherwise, they talk to USB pretty much the same, * so interface (un)binding, endpoint I/O queues, fault handling, and other * issues can usefully be addressed by this framework. */ // #define DEBUG // error path messages, extra info // #define VERBOSE // more; success messages #include <linux/module.h> #include <linux/sched.h> #include <linux/init.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/ethtool.h> #include <linux/workqueue.h> #include <linux/mii.h> #include <linux/usb.h> #include "usbnet.h" #define DRIVER_VERSION "22-Aug-2005" /*-------------------------------------------------------------------------*/ /* * Nineteen USB 1.1 max size bulk transactions per frame (ms), max. * Several dozen bytes of IPv4 data can fit in two such transactions. * One maximum size Ethernet packet takes twenty four of them. * For high speed, each frame comfortably fits almost 36 max size * Ethernet packets (so queues should be bigger). * * REVISIT qlens should be members of 'struct usbnet'; the goal is to * let the USB host controller be busy for 5msec or more before an irq * is required, under load. Jumbograms change the equation. */ #define RX_MAX_QUEUE_MEMORY (60 * 1518) #define RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \ (RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4) #define TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \ (RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4) // reawaken network queue this soon after stopping; else watchdog barks #define TX_TIMEOUT_JIFFIES (5*HZ) // throttle rx/tx briefly after some faults, so khubd might disconnect() // us (it polls at HZ/4 usually) before we report too many false errors. #define THROTTLE_JIFFIES (HZ/8) // between wakeups #define UNLINK_TIMEOUT_MS 3 /*-------------------------------------------------------------------------*/ // randomly generated ethernet address static u8 node_id [ETH_ALEN]; static const char driver_name [] = "usbnet"; /* use ethtool to change the level for any given device */ static int msg_level = -1; module_param (msg_level, int, 0); MODULE_PARM_DESC (msg_level, "Override default message level"); /*-------------------------------------------------------------------------*/ /* handles CDC Ethernet and many other network "bulk data" interfaces */ int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf) { int tmp; struct usb_host_interface *alt = NULL; struct usb_host_endpoint *in = NULL, *out = NULL; struct usb_host_endpoint *status = NULL; for (tmp = 0; tmp < intf->num_altsetting; tmp++) { unsigned ep; in = out = status = NULL; alt = intf->altsetting + tmp; /* take the first altsetting with in-bulk + out-bulk; * remember any status endpoint, just in case; * ignore other endpoints and altsetttings. */ for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) { struct usb_host_endpoint *e; int intr = 0; e = alt->endpoint + ep; switch (e->desc.bmAttributes) { case USB_ENDPOINT_XFER_INT: if (!(e->desc.bEndpointAddress & USB_DIR_IN)) continue; intr = 1; /* FALLTHROUGH */ case USB_ENDPOINT_XFER_BULK: break; default: continue; } if (e->desc.bEndpointAddress & USB_DIR_IN) { if (!intr && !in) in = e; else if (intr && !status) status = e; } else { if (!out) out = e; } } if (in && out) break; } if (!alt || !in || !out) return -EINVAL; if (alt->desc.bAlternateSetting != 0 || !(dev->driver_info->flags & FLAG_NO_SETINT)) { tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber, alt->desc.bAlternateSetting); if (tmp < 0) return tmp; } dev->in = usb_rcvbulkpipe (dev->udev, in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK); dev->out = usb_sndbulkpipe (dev->udev, out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK); dev->status = status; return 0; } EXPORT_SYMBOL_GPL(usbnet_get_endpoints); static void intr_complete (struct urb *urb); static int init_status (struct usbnet *dev, struct usb_interface *intf) { char *buf = NULL; unsigned pipe = 0; unsigned maxp; unsigned period; if (!dev->driver_info->status) return 0; pipe = usb_rcvintpipe (dev->udev, dev->status->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK); maxp = usb_maxpacket (dev->udev, pipe, 0); /* avoid 1 msec chatter: min 8 msec poll rate */ period = max ((int) dev->status->desc.bInterval, (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3); buf = kmalloc (maxp, SLAB_KERNEL); if (buf) { dev->interrupt = usb_alloc_urb (0, SLAB_KERNEL); if (!dev->interrupt) { kfree (buf); return -ENOMEM; } else { usb_fill_int_urb(dev->interrupt, dev->udev, pipe, buf, maxp, intr_complete, dev, period); dev_dbg(&intf->dev, "status ep%din, %d bytes period %d\n", usb_pipeendpoint(pipe), maxp, period); } } return 0; } /* Passes this packet up the stack, updating its accounting. * Some link protocols batch packets, so their rx_fixup paths * can return clones as well as just modify the original skb. */ void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb) { int status; skb->dev = dev->net; skb->protocol = eth_type_trans (skb, dev->net); dev->stats.rx_packets++; dev->stats.rx_bytes += skb->len; if (netif_msg_rx_status (dev)) devdbg (dev, "< rx, len %zu, type 0x%x", skb->len + sizeof (struct ethhdr), skb->protocol); memset (skb->cb, 0, sizeof (struct skb_data)); status = netif_rx (skb); if (status != NET_RX_SUCCESS && netif_msg_rx_err (dev)) devdbg (dev, "netif_rx status %d", status); } EXPORT_SYMBOL_GPL(usbnet_skb_return); /*------------------------------------------------------------------------- * * Network Device Driver (peer link to "Host Device", from USB host) * *-------------------------------------------------------------------------*/ static int usbnet_change_mtu (struct net_device *net, int new_mtu) { struct usbnet *dev = netdev_priv(net); int ll_mtu = new_mtu + net->hard_header_len; int old_hard_mtu = dev->hard_mtu; int old_rx_urb_size = dev->rx_urb_size; if (new_mtu <= 0) return -EINVAL; // no second zero-length packet read wanted after mtu-sized packets if ((ll_mtu % dev->maxpacket) == 0) return -EDOM; net->mtu = new_mtu; dev->hard_mtu = net->mtu + net->hard_header_len; if (dev->rx_urb_size == old_hard_mtu) { dev->rx_urb_size = dev->hard_mtu; if (dev->rx_urb_size > old_rx_urb_size) usbnet_unlink_rx_urbs(dev); } return 0; } /*-------------------------------------------------------------------------*/ static struct net_device_stats *usbnet_get_stats (struct net_device *net) { struct usbnet *dev = netdev_priv(net); return &dev->stats; } /*-------------------------------------------------------------------------*/ /* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from * completion callbacks. 2.5 should have fixed those bugs... */ static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list) { unsigned long flags; spin_lock_irqsave(&list->lock, flags); __skb_unlink(skb, list); spin_unlock(&list->lock); spin_lock(&dev->done.lock); __skb_queue_tail(&dev->done, skb); if (dev->done.qlen == 1) tasklet_schedule(&dev->bh); spin_unlock_irqrestore(&dev->done.lock, flags); } /* some work can't be done in tasklets, so we use keventd * * NOTE: annoying asymmetry: if it's active, schedule_work() fails, * but tasklet_schedule() doesn't. hope the failure is rare. */ void usbnet_defer_kevent (struct usbnet *dev, int work) { set_bit (work, &dev->flags); if (!schedule_work (&dev->kevent)) deverr (dev, "kevent %d may have been dropped", work); else devdbg (dev, "kevent %d scheduled", work); } EXPORT_SYMBOL_GPL(usbnet_defer_kevent); /*-------------------------------------------------------------------------*/ static void rx_complete (struct urb *urb); static void rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags) { struct sk_buff *skb; struct skb_data *entry; int retval = 0; unsigned long lockflags; size_t size = dev->rx_urb_size; if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) { if (netif_msg_rx_err (dev)) devdbg (dev, "no rx skb"); usbnet_defer_kevent (dev, EVENT_RX_MEMORY); usb_free_urb (urb); return; } skb_reserve (skb, NET_IP_ALIGN); entry = (struct skb_data *) skb->cb; entry->urb = urb; entry->dev = dev; entry->state = rx_start; entry->length = 0; usb_fill_bulk_urb (urb, dev->udev, dev->in, skb->data, size, rx_complete, skb); spin_lock_irqsave (&dev->rxq.lock, lockflags); if (netif_running (dev->net) && netif_device_present (dev->net) && !test_bit (EVENT_RX_HALT, &dev->flags)) { switch (retval = usb_submit_urb (urb, GFP_ATOMIC)){ case -EPIPE: usbnet_defer_kevent (dev, EVENT_RX_HALT); break; case -ENOMEM: usbnet_defer_kevent (dev, EVENT_RX_MEMORY); break; case -ENODEV: if (netif_msg_ifdown (dev)) devdbg (dev, "device gone"); netif_device_detach (dev->net); break; default: if (netif_msg_rx_err (dev)) devdbg (dev, "rx submit, %d", retval); tasklet_schedule (&dev->bh); break; case 0: __skb_queue_tail (&dev->rxq, skb); } } else { if (netif_msg_ifdown (dev)) devdbg (dev, "rx: stopped"); retval = -ENOLINK; } spin_unlock_irqrestore (&dev->rxq.lock, lockflags); if (retval) { dev_kfree_skb_any (skb); usb_free_urb (urb); } } /*-------------------------------------------------------------------------*/ static inline void rx_process (struct usbnet *dev, struct sk_buff *skb) { if (dev->driver_info->rx_fixup && !dev->driver_info->rx_fixup (dev, skb)) goto error; // else network stack removes extra byte if we forced a short packet if (skb->len) usbnet_skb_return (dev, skb); else { if (netif_msg_rx_err (dev)) devdbg (dev, "drop"); error: dev->stats.rx_errors++; skb_queue_tail (&dev->done, skb); } } /*-------------------------------------------------------------------------*/ static void rx_complete (struct urb *urb) { struct sk_buff *skb = (struct sk_buff *) urb->context; struct skb_data *entry = (struct skb_data *) skb->cb; struct usbnet *dev = entry->dev; int urb_status = urb->status; skb_put (skb, urb->actual_length); entry->state = rx_done; entry->urb = NULL; switch (urb_status) { // success case 0: if (skb->len < dev->net->hard_header_len) { entry->state = rx_cleanup; dev->stats.rx_errors++; dev->stats.rx_length_errors++; if (netif_msg_rx_err (dev)) devdbg (dev, "rx length %d", skb->len); } break; // stalls need manual reset. this is rare ... except that // when going through USB 2.0 TTs, unplug appears this way. // we avoid the highspeed version of the ETIMEOUT/EILSEQ // storm, recovering as needed. case -EPIPE: dev->stats.rx_errors++; usbnet_defer_kevent (dev, EVENT_RX_HALT); // FALLTHROUGH // software-driven interface shutdown case -ECONNRESET: // async unlink case -ESHUTDOWN: // hardware gone if (netif_msg_ifdown (dev)) devdbg (dev, "rx shutdown, code %d", urb_status); goto block; // we get controller i/o faults during khubd disconnect() delays. // throttle down resubmits, to avoid log floods; just temporarily, // so we still recover when the fault isn't a khubd delay. case -EPROTO: case -ETIME: case -EILSEQ: dev->stats.rx_errors++; if (!timer_pending (&dev->delay)) { mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES); if (netif_msg_link (dev)) devdbg (dev, "rx throttle %d", urb_status); } block: entry->state = rx_cleanup; entry->urb = urb; urb = NULL; break; // data overrun ... flush fifo? case -EOVERFLOW: dev->stats.rx_over_errors++; // FALLTHROUGH default: entry->state = rx_cleanup; dev->stats.rx_errors++; if (netif_msg_rx_err (dev)) devdbg (dev, "rx status %d", urb_status); break; } defer_bh(dev, skb, &dev->rxq); if (urb) { if (netif_running (dev->net) && !test_bit (EVENT_RX_HALT, &dev->flags)) { rx_submit (dev, urb, GFP_ATOMIC); return; } usb_free_urb (urb); } if (netif_msg_rx_err (dev)) devdbg (dev, "no read resubmitted"); } static void intr_complete (struct urb *urb) { struct usbnet *dev = urb->context; int status = urb->status; switch (status) { /* success */ case 0: dev->driver_info->status(dev, urb); break; /* software-driven interface shutdown */ case -ENOENT: // urb killed case -ESHUTDOWN: // hardware gone if (netif_msg_ifdown (dev)) devdbg (dev, "intr shutdown, code %d", status); return; /* NOTE: not throttling like RX/TX, since this endpoint * already polls infrequently */ default: devdbg (dev, "intr status %d", status); break; } if (!netif_running (dev->net)) return; memset(urb->transfer_buffer, 0, urb->transfer_buffer_length); status = usb_submit_urb (urb, GFP_ATOMIC); if (status != 0 && netif_msg_timer (dev)) deverr(dev, "intr resubmit --> %d", status); } /*-------------------------------------------------------------------------*/ // unlink pending rx/tx; completion handlers do all other cleanup static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q) { unsigned long flags; struct sk_buff *skb, *skbnext; int count = 0; spin_lock_irqsave (&q->lock, flags); for (skb = q->next; skb != (struct sk_buff *) q; skb = skbnext) { struct skb_data *entry; struct urb *urb; int retval; entry = (struct skb_data *) skb->cb; urb = entry->urb; skbnext = skb->next; // during some PM-driven resume scenarios, // these (async) unlinks complete immediately retval = usb_unlink_urb (urb); if (retval != -EINPROGRESS && retval != 0) devdbg (dev, "unlink urb err, %d", retval); else count++; } spin_unlock_irqrestore (&q->lock, flags); return count; } // Flush all pending rx urbs // minidrivers may need to do this when the MTU changes void usbnet_unlink_rx_urbs(struct usbnet *dev) { if (netif_running(dev->net)) { (void) unlink_urbs (dev, &dev->rxq); tasklet_schedule(&dev->bh); } } EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs); /*-------------------------------------------------------------------------*/ // precondition: never called in_interrupt static int usbnet_stop (struct net_device *net) { struct usbnet *dev = netdev_priv(net); int temp; DECLARE_WAIT_QUEUE_HEAD (unlink_wakeup); DECLARE_WAITQUEUE (wait, current); netif_stop_queue (net); if (netif_msg_ifdown (dev)) devinfo (dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld", dev->stats.rx_packets, dev->stats.tx_packets, dev->stats.rx_errors, dev->stats.tx_errors ); // ensure there are no more active urbs add_wait_queue (&unlink_wakeup, &wait); dev->wait = &unlink_wakeup; temp = unlink_urbs (dev, &dev->txq) + unlink_urbs (dev, &dev->rxq); // maybe wait for deletions to finish. while (!skb_queue_empty(&dev->rxq) && !skb_queue_empty(&dev->txq) && !skb_queue_empty(&dev->done)) { msleep(UNLINK_TIMEOUT_MS); if (netif_msg_ifdown (dev)) devdbg (dev, "waited for %d urb completions", temp); } dev->wait = NULL; remove_wait_queue (&unlink_wakeup, &wait); usb_kill_urb(dev->interrupt); /* deferred work (task, timer, softirq) must also stop. * can't flush_scheduled_work() until we drop rtnl (later), * else workers could deadlock; so make workers a NOP. */ dev->flags = 0; del_timer_sync (&dev->delay); tasklet_kill (&dev->bh); return 0; } /*-------------------------------------------------------------------------*/ // posts reads, and enables write queuing // precondition: never called in_interrupt static int usbnet_open (struct net_device *net) { struct usbnet *dev = netdev_priv(net); int retval = 0; struct driver_info *info = dev->driver_info; // put into "known safe" state if (info->reset && (retval = info->reset (dev)) < 0) { if (netif_msg_ifup (dev)) devinfo (dev, "open reset fail (%d) usbnet usb-%s-%s, %s", retval, dev->udev->bus->bus_name, dev->udev->devpath, info->description); goto done; } // insist peer be connected if (info->check_connect && (retval = info->check_connect (dev)) < 0) { if (netif_msg_ifup (dev)) devdbg (dev, "can't open; %d", retval); goto done; } /* start any status interrupt transfer */ if (dev->interrupt) { retval = usb_submit_urb (dev->interrupt, GFP_KERNEL); if (retval < 0) { if (netif_msg_ifup (dev)) deverr (dev, "intr submit %d", retval); goto done; } } netif_start_queue (net); if (netif_msg_ifup (dev)) { char *framing; if (dev->driver_info->flags & FLAG_FRAMING_NC) framing = "NetChip"; else if (dev->driver_info->flags & FLAG_FRAMING_GL) framing = "GeneSys"; else if (dev->driver_info->flags & FLAG_FRAMING_Z) framing = "Zaurus"; else if (dev->driver_info->flags & FLAG_FRAMING_RN) framing = "RNDIS"; else if (dev->driver_info->flags & FLAG_FRAMING_AX) framing = "ASIX"; else framing = "simple"; devinfo (dev, "open: enable queueing " "(rx %d, tx %d) mtu %d %s framing", (int)RX_QLEN (dev), (int)TX_QLEN (dev), dev->net->mtu, framing); } // delay posting reads until we're fully open tasklet_schedule (&dev->bh); done: return retval; } /*-------------------------------------------------------------------------*/ /* ethtool methods; minidrivers may need to add some more, but * they'll probably want to use this base set. */ void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info) { struct usbnet *dev = netdev_priv(net); /* REVISIT don't always return "usbnet" */ strncpy (info->driver, driver_name, sizeof info->driver); strncpy (info->version, DRIVER_VERSION, sizeof info->version); strncpy (info->fw_version, dev->driver_info->description, sizeof info->fw_version); usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info); } EXPORT_SYMBOL_GPL(usbnet_get_drvinfo); static u32 usbnet_get_link (struct net_device *net) { struct usbnet *dev = netdev_priv(net); /* If a check_connect is defined, return its result */ if (dev->driver_info->check_connect) return dev->driver_info->check_connect (dev) == 0; /* Otherwise, say we're up (to avoid breaking scripts) */ return 1; } u32 usbnet_get_msglevel (struct net_device *net) { struct usbnet *dev = netdev_priv(net); return dev->msg_enable; } EXPORT_SYMBOL_GPL(usbnet_get_msglevel); void usbnet_set_msglevel (struct net_device *net, u32 level) { struct usbnet *dev = netdev_priv(net); dev->msg_enable = level; } EXPORT_SYMBOL_GPL(usbnet_set_msglevel); /* drivers may override default ethtool_ops in their bind() routine */ static struct ethtool_ops usbnet_ethtool_ops = { .get_drvinfo = usbnet_get_drvinfo, .get_link = usbnet_get_link, .get_msglevel = usbnet_get_msglevel, .set_msglevel = usbnet_set_msglevel, }; /*-------------------------------------------------------------------------*/ /* work that cannot be done in interrupt context uses keventd. * * NOTE: with 2.5 we could do more of this using completion callbacks, * especially now that control transfers can be queued. */ static void kevent (void *data) { struct usbnet *dev = data; int status; /* usb_clear_halt() needs a thread context */ if (test_bit (EVENT_TX_HALT, &dev->flags)) { unlink_urbs (dev, &dev->txq); status = usb_clear_halt (dev->udev, dev->out); if (status < 0 && status != -EPIPE && status != -ESHUTDOWN) { if (netif_msg_tx_err (dev)) deverr (dev, "can't clear tx halt, status %d", status); } else { clear_bit (EVENT_TX_HALT, &dev->flags); if (status != -ESHUTDOWN) netif_wake_queue (dev->net); } } if (test_bit (EVENT_RX_HALT, &dev->flags)) { unlink_urbs (dev, &dev->rxq); status = usb_clear_halt (dev->udev, dev->in); if (status < 0 && status != -EPIPE && status != -ESHUTDOWN) { if (netif_msg_rx_err (dev)) deverr (dev, "can't clear rx halt, status %d", status); } else { clear_bit (EVENT_RX_HALT, &dev->flags); tasklet_schedule (&dev->bh); } } /* tasklet could resubmit itself forever if memory is tight */ if (test_bit (EVENT_RX_MEMORY, &dev->flags)) { struct urb *urb = NULL; if (netif_running (dev->net)) urb = usb_alloc_urb (0, GFP_KERNEL); else clear_bit (EVENT_RX_MEMORY, &dev->flags); if (urb != NULL) { clear_bit (EVENT_RX_MEMORY, &dev->flags); rx_submit (dev, urb, GFP_KERNEL); tasklet_schedule (&dev->bh); } } if (test_bit (EVENT_LINK_RESET, &dev->flags)) { struct driver_info *info = dev->driver_info; int retval = 0; clear_bit (EVENT_LINK_RESET, &dev->flags); if(info->link_reset && (retval = info->link_reset(dev)) < 0) { devinfo(dev, "link reset failed (%d) usbnet usb-%s-%s, %s", retval, dev->udev->bus->bus_name, dev->udev->devpath, info->description); } } if (dev->flags) devdbg (dev, "kevent done, flags = 0x%lx", dev->flags); } /*-------------------------------------------------------------------------*/ static void tx_complete (struct urb *urb) { struct sk_buff *skb = (struct sk_buff *) urb->context; struct skb_data *entry = (struct skb_data *) skb->cb; struct usbnet *dev = entry->dev; if (urb->status == 0) { dev->stats.tx_packets++; dev->stats.tx_bytes += entry->length; } else { dev->stats.tx_errors++; switch (urb->status) { case -EPIPE: usbnet_defer_kevent (dev, EVENT_TX_HALT); break; /* software-driven interface shutdown */ case -ECONNRESET: // async unlink case -ESHUTDOWN: // hardware gone break; // like rx, tx gets controller i/o faults during khubd delays // and so it uses the same throttling mechanism. case -EPROTO: case -ETIME: case -EILSEQ: if (!timer_pending (&dev->delay)) { mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES); if (netif_msg_link (dev)) devdbg (dev, "tx throttle %d", urb->status); } netif_stop_queue (dev->net); break; default: if (netif_msg_tx_err (dev)) devdbg (dev, "tx err %d", entry->urb->status); break; } } urb->dev = NULL; entry->state = tx_done; defer_bh(dev, skb, &dev->txq); } /*-------------------------------------------------------------------------*/ static void usbnet_tx_timeout (struct net_device *net) { struct usbnet *dev = netdev_priv(net); unlink_urbs (dev, &dev->txq); tasklet_schedule (&dev->bh); // FIXME: device recovery -- reset? } /*-------------------------------------------------------------------------*/ static int usbnet_start_xmit (struct sk_buff *skb, struct net_device *net) { struct usbnet *dev = netdev_priv(net); int length; int retval = NET_XMIT_SUCCESS; struct urb *urb = NULL; struct skb_data *entry; struct driver_info *info = dev->driver_info; unsigned long flags; // some devices want funky USB-level framing, for // win32 driver (usually) and/or hardware quirks if (info->tx_fixup) { skb = info->tx_fixup (dev, skb, GFP_ATOMIC); if (!skb) { if (netif_msg_tx_err (dev)) devdbg (dev, "can't tx_fixup skb"); goto drop; } } length = skb->len; if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) { if (netif_msg_tx_err (dev)) devdbg (dev, "no urb"); goto drop; } entry = (struct skb_data *) skb->cb; entry->urb = urb; entry->dev = dev; entry->state = tx_start; entry->length = length; usb_fill_bulk_urb (urb, dev->udev, dev->out, skb->data, skb->len, tx_complete, skb); /* don't assume the hardware handles USB_ZERO_PACKET * NOTE: strictly conforming cdc-ether devices should expect * the ZLP here, but ignore the one-byte packet. * * FIXME zero that byte, if it doesn't require a new skb. */ if ((length % dev->maxpacket) == 0) urb->transfer_buffer_length++; spin_lock_irqsave (&dev->txq.lock, flags); switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) { case -EPIPE: netif_stop_queue (net); usbnet_defer_kevent (dev, EVENT_TX_HALT); break; default: if (netif_msg_tx_err (dev)) devdbg (dev, "tx: submit urb err %d", retval); break; case 0: net->trans_start = jiffies; __skb_queue_tail (&dev->txq, skb); if (dev->txq.qlen >= TX_QLEN (dev)) netif_stop_queue (net); } spin_unlock_irqrestore (&dev->txq.lock, flags); if (retval) { if (netif_msg_tx_err (dev)) devdbg (dev, "drop, code %d", retval); drop: retval = NET_XMIT_SUCCESS; dev->stats.tx_dropped++; if (skb) dev_kfree_skb_any (skb); usb_free_urb (urb); } else if (netif_msg_tx_queued (dev)) { devdbg (dev, "> tx, len %d, type 0x%x", length, skb->protocol); } return retval; } /*-------------------------------------------------------------------------*/ // tasklet (work deferred from completions, in_irq) or timer static void usbnet_bh (unsigned long param) { struct usbnet *dev = (struct usbnet *) param; struct sk_buff *skb; struct skb_data *entry; while ((skb = skb_dequeue (&dev->done))) { entry = (struct skb_data *) skb->cb; switch (entry->state) { case rx_done: entry->state = rx_cleanup; rx_process (dev, skb); continue; case tx_done: case rx_cleanup: usb_free_urb (entry->urb); dev_kfree_skb (skb); continue; default: devdbg (dev, "bogus skb state %d", entry->state); } } // waiting for all pending urbs to complete? if (dev->wait) { if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) { wake_up (dev->wait); } // or are we maybe short a few urbs? } else if (netif_running (dev->net) && netif_device_present (dev->net) && !timer_pending (&dev->delay) && !test_bit (EVENT_RX_HALT, &dev->flags)) { int temp = dev->rxq.qlen; int qlen = RX_QLEN (dev); if (temp < qlen) { struct urb *urb; int i; // don't refill the queue all at once for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) { urb = usb_alloc_urb (0, GFP_ATOMIC); if (urb != NULL) rx_submit (dev, urb, GFP_ATOMIC); } if (temp != dev->rxq.qlen && netif_msg_link (dev)) devdbg (dev, "rxqlen %d --> %d", temp, dev->rxq.qlen); if (dev->rxq.qlen < qlen) tasklet_schedule (&dev->bh); } if (dev->txq.qlen < TX_QLEN (dev)) netif_wake_queue (dev->net); } } /*------------------------------------------------------------------------- * * USB Device Driver support * *-------------------------------------------------------------------------*/ // precondition: never called in_interrupt void usbnet_disconnect (struct usb_interface *intf) { struct usbnet *dev; struct usb_device *xdev; struct net_device *net; dev = usb_get_intfdata(intf); usb_set_intfdata(intf, NULL); if (!dev) return; xdev = interface_to_usbdev (intf); if (netif_msg_probe (dev)) devinfo (dev, "unregister '%s' usb-%s-%s, %s", intf->dev.driver->name, xdev->bus->bus_name, xdev->devpath, dev->driver_info->description); net = dev->net; unregister_netdev (net); /* we don't hold rtnl here ... */ flush_scheduled_work (); if (dev->driver_info->unbind) dev->driver_info->unbind (dev, intf); free_netdev(net); usb_put_dev (xdev); } EXPORT_SYMBOL_GPL(usbnet_disconnect); /*-------------------------------------------------------------------------*/ // precondition: never called in_interrupt int usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod) { struct usbnet *dev; struct net_device *net; struct usb_host_interface *interface; struct driver_info *info; struct usb_device *xdev; int status; info = (struct driver_info *) prod->driver_info; if (!info) { dev_dbg (&udev->dev, "blacklisted by %s\n", driver_name); return -ENODEV; } xdev = interface_to_usbdev (udev); interface = udev->cur_altsetting; usb_get_dev (xdev); status = -ENOMEM; // set up our own records net = alloc_etherdev(sizeof(*dev)); if (!net) { dbg ("can't kmalloc dev"); goto out; } dev = netdev_priv(net); dev->udev = xdev; dev->driver_info = info; dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK); skb_queue_head_init (&dev->rxq); skb_queue_head_init (&dev->txq); skb_queue_head_init (&dev->done); dev->bh.func = usbnet_bh; dev->bh.data = (unsigned long) dev; INIT_WORK (&dev->kevent, kevent, dev); dev->delay.function = usbnet_bh; dev->delay.data = (unsigned long) dev; init_timer (&dev->delay); SET_MODULE_OWNER (net); dev->net = net; strcpy (net->name, "usb%d"); memcpy (net->dev_addr, node_id, sizeof node_id); /* rx and tx sides can use different message sizes; * bind() should set rx_urb_size in that case. */ dev->hard_mtu = net->mtu + net->hard_header_len; #if 0 // dma_supported() is deeply broken on almost all architectures // possible with some EHCI controllers if (dma_supported (&udev->dev, DMA_64BIT_MASK)) net->features |= NETIF_F_HIGHDMA; #endif net->change_mtu = usbnet_change_mtu; net->get_stats = usbnet_get_stats; net->hard_start_xmit = usbnet_start_xmit; net->open = usbnet_open; net->stop = usbnet_stop; net->watchdog_timeo = TX_TIMEOUT_JIFFIES; net->tx_timeout = usbnet_tx_timeout; net->ethtool_ops = &usbnet_ethtool_ops; // allow device-specific bind/init procedures // NOTE net->name still not usable ... if (info->bind) { status = info->bind (dev, udev); // heuristic: "usb%d" for links we know are two-host, // else "eth%d" when there's reasonable doubt. userspace // can rename the link if it knows better. if ((dev->driver_info->flags & FLAG_ETHER) != 0 && (net->dev_addr [0] & 0x02) == 0) strcpy (net->name, "eth%d"); /* maybe the remote can't receive an Ethernet MTU */ if (net->mtu > (dev->hard_mtu - net->hard_header_len)) net->mtu = dev->hard_mtu - net->hard_header_len; } else if (!info->in || !info->out) status = usbnet_get_endpoints (dev, udev); else { dev->in = usb_rcvbulkpipe (xdev, info->in); dev->out = usb_sndbulkpipe (xdev, info->out); if (!(info->flags & FLAG_NO_SETINT)) status = usb_set_interface (xdev, interface->desc.bInterfaceNumber, interface->desc.bAlternateSetting); else status = 0; } if (status == 0 && dev->status) status = init_status (dev, udev); if (status < 0) goto out1; if (!dev->rx_urb_size) dev->rx_urb_size = dev->hard_mtu; dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1); SET_NETDEV_DEV(net, &udev->dev); status = register_netdev (net); if (status) goto out3; if (netif_msg_probe (dev)) devinfo (dev, "register '%s' at usb-%s-%s, %s, " "%02x:%02x:%02x:%02x:%02x:%02x", udev->dev.driver->name, xdev->bus->bus_name, xdev->devpath, dev->driver_info->description, net->dev_addr [0], net->dev_addr [1], net->dev_addr [2], net->dev_addr [3], net->dev_addr [4], net->dev_addr [5]); // ok, it's ready to go. usb_set_intfdata (udev, dev); // start as if the link is up netif_device_attach (net); return 0; out3: if (info->unbind) info->unbind (dev, udev); out1: free_netdev(net); out: usb_put_dev(xdev); return status; } EXPORT_SYMBOL_GPL(usbnet_probe); /*-------------------------------------------------------------------------*/ /* FIXME these suspend/resume methods assume non-CDC style * devices, with only one interface. */ int usbnet_suspend (struct usb_interface *intf, pm_message_t message) { struct usbnet *dev = usb_get_intfdata(intf); /* accelerate emptying of the rx and queues, to avoid * having everything error out. */ netif_device_detach (dev->net); (void) unlink_urbs (dev, &dev->rxq); (void) unlink_urbs (dev, &dev->txq); return 0; } EXPORT_SYMBOL_GPL(usbnet_suspend); int usbnet_resume (struct usb_interface *intf) { struct usbnet *dev = usb_get_intfdata(intf); netif_device_attach (dev->net); tasklet_schedule (&dev->bh); return 0; } EXPORT_SYMBOL_GPL(usbnet_resume); /*-------------------------------------------------------------------------*/ static int __init usbnet_init(void) { /* compiler should optimize this out */ BUG_ON (sizeof (((struct sk_buff *)0)->cb) < sizeof (struct skb_data)); random_ether_addr(node_id); return 0; } module_init(usbnet_init); static void __exit usbnet_exit(void) { } module_exit(usbnet_exit); MODULE_AUTHOR("David Brownell"); MODULE_DESCRIPTION("USB network driver framework"); MODULE_LICENSE("GPL");