968 lines
24 KiB
C
968 lines
24 KiB
C
/*
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* u_ether.c -- Ethernet-over-USB link layer utilities for Gadget stack
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*
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* Copyright (C) 2003-2005,2008 David Brownell
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* Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
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* Copyright (C) 2008 Nokia Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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/* #define VERBOSE_DEBUG */
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#include <linux/kernel.h>
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#include <linux/utsname.h>
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#include <linux/device.h>
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#include <linux/ctype.h>
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#include <linux/etherdevice.h>
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#include <linux/ethtool.h>
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#include "u_ether.h"
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/*
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* This component encapsulates the Ethernet link glue needed to provide
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* one (!) network link through the USB gadget stack, normally "usb0".
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*
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* The control and data models are handled by the function driver which
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* connects to this code; such as CDC Ethernet, "CDC Subset", or RNDIS.
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* That includes all descriptor and endpoint management.
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*
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* Link level addressing is handled by this component using module
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* parameters; if no such parameters are provided, random link level
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* addresses are used. Each end of the link uses one address. The
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* host end address is exported in various ways, and is often recorded
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* in configuration databases.
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*
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* The driver which assembles each configuration using such a link is
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* responsible for ensuring that each configuration includes at most one
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* instance of is network link. (The network layer provides ways for
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* this single "physical" link to be used by multiple virtual links.)
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*/
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#define UETH__VERSION "29-May-2008"
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struct eth_dev {
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/* lock is held while accessing port_usb
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* or updating its backlink port_usb->ioport
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*/
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spinlock_t lock;
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struct gether *port_usb;
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struct net_device *net;
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struct usb_gadget *gadget;
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spinlock_t req_lock; /* guard {rx,tx}_reqs */
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struct list_head tx_reqs, rx_reqs;
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atomic_t tx_qlen;
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unsigned header_len;
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struct sk_buff *(*wrap)(struct sk_buff *skb);
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int (*unwrap)(struct sk_buff *skb);
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struct work_struct work;
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unsigned long todo;
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#define WORK_RX_MEMORY 0
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bool zlp;
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u8 host_mac[ETH_ALEN];
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};
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/*-------------------------------------------------------------------------*/
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#define RX_EXTRA 20 /* bytes guarding against rx overflows */
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#define DEFAULT_QLEN 2 /* double buffering by default */
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#ifdef CONFIG_USB_GADGET_DUALSPEED
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static unsigned qmult = 5;
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module_param(qmult, uint, S_IRUGO|S_IWUSR);
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MODULE_PARM_DESC(qmult, "queue length multiplier at high speed");
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#else /* full speed (low speed doesn't do bulk) */
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#define qmult 1
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#endif
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/* for dual-speed hardware, use deeper queues at highspeed */
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static inline int qlen(struct usb_gadget *gadget)
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{
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if (gadget_is_dualspeed(gadget) && gadget->speed == USB_SPEED_HIGH)
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return qmult * DEFAULT_QLEN;
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else
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return DEFAULT_QLEN;
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}
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/*-------------------------------------------------------------------------*/
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/* REVISIT there must be a better way than having two sets
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* of debug calls ...
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*/
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#undef DBG
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#undef VDBG
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#undef ERROR
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#undef INFO
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#define xprintk(d, level, fmt, args...) \
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printk(level "%s: " fmt , (d)->net->name , ## args)
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#ifdef DEBUG
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#undef DEBUG
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#define DBG(dev, fmt, args...) \
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xprintk(dev , KERN_DEBUG , fmt , ## args)
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#else
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#define DBG(dev, fmt, args...) \
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do { } while (0)
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#endif /* DEBUG */
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#ifdef VERBOSE_DEBUG
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#define VDBG DBG
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#else
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#define VDBG(dev, fmt, args...) \
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do { } while (0)
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#endif /* DEBUG */
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#define ERROR(dev, fmt, args...) \
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xprintk(dev , KERN_ERR , fmt , ## args)
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#define INFO(dev, fmt, args...) \
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xprintk(dev , KERN_INFO , fmt , ## args)
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/*-------------------------------------------------------------------------*/
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/* NETWORK DRIVER HOOKUP (to the layer above this driver) */
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static int ueth_change_mtu(struct net_device *net, int new_mtu)
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{
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struct eth_dev *dev = netdev_priv(net);
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unsigned long flags;
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int status = 0;
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/* don't change MTU on "live" link (peer won't know) */
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spin_lock_irqsave(&dev->lock, flags);
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if (dev->port_usb)
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status = -EBUSY;
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else if (new_mtu <= ETH_HLEN || new_mtu > ETH_FRAME_LEN)
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status = -ERANGE;
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else
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net->mtu = new_mtu;
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spin_unlock_irqrestore(&dev->lock, flags);
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return status;
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}
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static void eth_get_drvinfo(struct net_device *net, struct ethtool_drvinfo *p)
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{
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struct eth_dev *dev = netdev_priv(net);
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strlcpy(p->driver, "g_ether", sizeof p->driver);
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strlcpy(p->version, UETH__VERSION, sizeof p->version);
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strlcpy(p->fw_version, dev->gadget->name, sizeof p->fw_version);
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strlcpy(p->bus_info, dev_name(&dev->gadget->dev), sizeof p->bus_info);
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}
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/* REVISIT can also support:
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* - WOL (by tracking suspends and issuing remote wakeup)
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* - msglevel (implies updated messaging)
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* - ... probably more ethtool ops
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*/
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static struct ethtool_ops ops = {
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.get_drvinfo = eth_get_drvinfo,
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.get_link = ethtool_op_get_link,
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};
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static void defer_kevent(struct eth_dev *dev, int flag)
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{
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if (test_and_set_bit(flag, &dev->todo))
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return;
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if (!schedule_work(&dev->work))
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ERROR(dev, "kevent %d may have been dropped\n", flag);
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else
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DBG(dev, "kevent %d scheduled\n", flag);
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}
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static void rx_complete(struct usb_ep *ep, struct usb_request *req);
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static int
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rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags)
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{
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struct sk_buff *skb;
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int retval = -ENOMEM;
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size_t size = 0;
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struct usb_ep *out;
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unsigned long flags;
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spin_lock_irqsave(&dev->lock, flags);
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if (dev->port_usb)
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out = dev->port_usb->out_ep;
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else
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out = NULL;
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spin_unlock_irqrestore(&dev->lock, flags);
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if (!out)
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return -ENOTCONN;
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/* Padding up to RX_EXTRA handles minor disagreements with host.
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* Normally we use the USB "terminate on short read" convention;
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* so allow up to (N*maxpacket), since that memory is normally
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* already allocated. Some hardware doesn't deal well with short
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* reads (e.g. DMA must be N*maxpacket), so for now don't trim a
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* byte off the end (to force hardware errors on overflow).
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*
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* RNDIS uses internal framing, and explicitly allows senders to
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* pad to end-of-packet. That's potentially nice for speed, but
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* means receivers can't recover lost synch on their own (because
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* new packets don't only start after a short RX).
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*/
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size += sizeof(struct ethhdr) + dev->net->mtu + RX_EXTRA;
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size += dev->port_usb->header_len;
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size += out->maxpacket - 1;
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size -= size % out->maxpacket;
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skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);
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if (skb == NULL) {
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DBG(dev, "no rx skb\n");
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goto enomem;
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}
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/* Some platforms perform better when IP packets are aligned,
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* but on at least one, checksumming fails otherwise. Note:
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* RNDIS headers involve variable numbers of LE32 values.
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*/
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skb_reserve(skb, NET_IP_ALIGN);
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req->buf = skb->data;
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req->length = size;
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req->complete = rx_complete;
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req->context = skb;
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retval = usb_ep_queue(out, req, gfp_flags);
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if (retval == -ENOMEM)
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enomem:
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defer_kevent(dev, WORK_RX_MEMORY);
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if (retval) {
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DBG(dev, "rx submit --> %d\n", retval);
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if (skb)
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dev_kfree_skb_any(skb);
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spin_lock_irqsave(&dev->req_lock, flags);
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list_add(&req->list, &dev->rx_reqs);
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spin_unlock_irqrestore(&dev->req_lock, flags);
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}
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return retval;
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}
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static void rx_complete(struct usb_ep *ep, struct usb_request *req)
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{
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struct sk_buff *skb = req->context;
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struct eth_dev *dev = ep->driver_data;
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int status = req->status;
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switch (status) {
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/* normal completion */
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case 0:
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skb_put(skb, req->actual);
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if (dev->unwrap)
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status = dev->unwrap(skb);
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if (status < 0
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|| ETH_HLEN > skb->len
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|| skb->len > ETH_FRAME_LEN) {
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dev->net->stats.rx_errors++;
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dev->net->stats.rx_length_errors++;
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DBG(dev, "rx length %d\n", skb->len);
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break;
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}
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skb->protocol = eth_type_trans(skb, dev->net);
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dev->net->stats.rx_packets++;
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dev->net->stats.rx_bytes += skb->len;
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/* no buffer copies needed, unless hardware can't
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* use skb buffers.
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*/
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status = netif_rx(skb);
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skb = NULL;
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break;
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/* software-driven interface shutdown */
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case -ECONNRESET: /* unlink */
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case -ESHUTDOWN: /* disconnect etc */
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VDBG(dev, "rx shutdown, code %d\n", status);
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goto quiesce;
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/* for hardware automagic (such as pxa) */
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case -ECONNABORTED: /* endpoint reset */
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DBG(dev, "rx %s reset\n", ep->name);
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defer_kevent(dev, WORK_RX_MEMORY);
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quiesce:
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dev_kfree_skb_any(skb);
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goto clean;
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/* data overrun */
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case -EOVERFLOW:
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dev->net->stats.rx_over_errors++;
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/* FALLTHROUGH */
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default:
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dev->net->stats.rx_errors++;
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DBG(dev, "rx status %d\n", status);
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break;
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}
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if (skb)
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dev_kfree_skb_any(skb);
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if (!netif_running(dev->net)) {
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clean:
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spin_lock(&dev->req_lock);
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list_add(&req->list, &dev->rx_reqs);
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spin_unlock(&dev->req_lock);
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req = NULL;
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}
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if (req)
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rx_submit(dev, req, GFP_ATOMIC);
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}
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static int prealloc(struct list_head *list, struct usb_ep *ep, unsigned n)
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{
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unsigned i;
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struct usb_request *req;
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if (!n)
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return -ENOMEM;
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/* queue/recycle up to N requests */
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i = n;
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list_for_each_entry(req, list, list) {
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if (i-- == 0)
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goto extra;
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}
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while (i--) {
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req = usb_ep_alloc_request(ep, GFP_ATOMIC);
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if (!req)
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return list_empty(list) ? -ENOMEM : 0;
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list_add(&req->list, list);
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}
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return 0;
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extra:
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/* free extras */
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for (;;) {
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struct list_head *next;
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next = req->list.next;
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list_del(&req->list);
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usb_ep_free_request(ep, req);
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if (next == list)
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break;
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req = container_of(next, struct usb_request, list);
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}
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return 0;
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}
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static int alloc_requests(struct eth_dev *dev, struct gether *link, unsigned n)
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{
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int status;
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spin_lock(&dev->req_lock);
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status = prealloc(&dev->tx_reqs, link->in_ep, n);
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if (status < 0)
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goto fail;
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status = prealloc(&dev->rx_reqs, link->out_ep, n);
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if (status < 0)
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goto fail;
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goto done;
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fail:
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DBG(dev, "can't alloc requests\n");
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done:
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spin_unlock(&dev->req_lock);
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return status;
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}
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static void rx_fill(struct eth_dev *dev, gfp_t gfp_flags)
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{
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struct usb_request *req;
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unsigned long flags;
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/* fill unused rxq slots with some skb */
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spin_lock_irqsave(&dev->req_lock, flags);
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while (!list_empty(&dev->rx_reqs)) {
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req = container_of(dev->rx_reqs.next,
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struct usb_request, list);
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list_del_init(&req->list);
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spin_unlock_irqrestore(&dev->req_lock, flags);
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if (rx_submit(dev, req, gfp_flags) < 0) {
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defer_kevent(dev, WORK_RX_MEMORY);
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return;
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}
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spin_lock_irqsave(&dev->req_lock, flags);
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}
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spin_unlock_irqrestore(&dev->req_lock, flags);
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}
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static void eth_work(struct work_struct *work)
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{
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struct eth_dev *dev = container_of(work, struct eth_dev, work);
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if (test_and_clear_bit(WORK_RX_MEMORY, &dev->todo)) {
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if (netif_running(dev->net))
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rx_fill(dev, GFP_KERNEL);
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}
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if (dev->todo)
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DBG(dev, "work done, flags = 0x%lx\n", dev->todo);
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}
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|
|
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static void tx_complete(struct usb_ep *ep, struct usb_request *req)
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{
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struct sk_buff *skb = req->context;
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struct eth_dev *dev = ep->driver_data;
|
|
|
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switch (req->status) {
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default:
|
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dev->net->stats.tx_errors++;
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VDBG(dev, "tx err %d\n", req->status);
|
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/* FALLTHROUGH */
|
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case -ECONNRESET: /* unlink */
|
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case -ESHUTDOWN: /* disconnect etc */
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break;
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case 0:
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dev->net->stats.tx_bytes += skb->len;
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}
|
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dev->net->stats.tx_packets++;
|
|
|
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spin_lock(&dev->req_lock);
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list_add(&req->list, &dev->tx_reqs);
|
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spin_unlock(&dev->req_lock);
|
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dev_kfree_skb_any(skb);
|
|
|
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atomic_dec(&dev->tx_qlen);
|
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if (netif_carrier_ok(dev->net))
|
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netif_wake_queue(dev->net);
|
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}
|
|
|
|
static inline int is_promisc(u16 cdc_filter)
|
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{
|
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return cdc_filter & USB_CDC_PACKET_TYPE_PROMISCUOUS;
|
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}
|
|
|
|
static int eth_start_xmit(struct sk_buff *skb, struct net_device *net)
|
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{
|
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struct eth_dev *dev = netdev_priv(net);
|
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int length = skb->len;
|
|
int retval;
|
|
struct usb_request *req = NULL;
|
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unsigned long flags;
|
|
struct usb_ep *in;
|
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u16 cdc_filter;
|
|
|
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spin_lock_irqsave(&dev->lock, flags);
|
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if (dev->port_usb) {
|
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in = dev->port_usb->in_ep;
|
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cdc_filter = dev->port_usb->cdc_filter;
|
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} else {
|
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in = NULL;
|
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cdc_filter = 0;
|
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}
|
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spin_unlock_irqrestore(&dev->lock, flags);
|
|
|
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if (!in) {
|
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dev_kfree_skb_any(skb);
|
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return 0;
|
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}
|
|
|
|
/* apply outgoing CDC or RNDIS filters */
|
|
if (!is_promisc(cdc_filter)) {
|
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u8 *dest = skb->data;
|
|
|
|
if (is_multicast_ether_addr(dest)) {
|
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u16 type;
|
|
|
|
/* ignores USB_CDC_PACKET_TYPE_MULTICAST and host
|
|
* SET_ETHERNET_MULTICAST_FILTERS requests
|
|
*/
|
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if (is_broadcast_ether_addr(dest))
|
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type = USB_CDC_PACKET_TYPE_BROADCAST;
|
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else
|
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type = USB_CDC_PACKET_TYPE_ALL_MULTICAST;
|
|
if (!(cdc_filter & type)) {
|
|
dev_kfree_skb_any(skb);
|
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return 0;
|
|
}
|
|
}
|
|
/* ignores USB_CDC_PACKET_TYPE_DIRECTED */
|
|
}
|
|
|
|
spin_lock_irqsave(&dev->req_lock, flags);
|
|
/*
|
|
* this freelist can be empty if an interrupt triggered disconnect()
|
|
* and reconfigured the gadget (shutting down this queue) after the
|
|
* network stack decided to xmit but before we got the spinlock.
|
|
*/
|
|
if (list_empty(&dev->tx_reqs)) {
|
|
spin_unlock_irqrestore(&dev->req_lock, flags);
|
|
return NETDEV_TX_BUSY;
|
|
}
|
|
|
|
req = container_of(dev->tx_reqs.next, struct usb_request, list);
|
|
list_del(&req->list);
|
|
|
|
/* temporarily stop TX queue when the freelist empties */
|
|
if (list_empty(&dev->tx_reqs))
|
|
netif_stop_queue(net);
|
|
spin_unlock_irqrestore(&dev->req_lock, flags);
|
|
|
|
/* no buffer copies needed, unless the network stack did it
|
|
* or the hardware can't use skb buffers.
|
|
* or there's not enough space for extra headers we need
|
|
*/
|
|
if (dev->wrap) {
|
|
struct sk_buff *skb_new;
|
|
|
|
skb_new = dev->wrap(skb);
|
|
if (!skb_new)
|
|
goto drop;
|
|
|
|
dev_kfree_skb_any(skb);
|
|
skb = skb_new;
|
|
length = skb->len;
|
|
}
|
|
req->buf = skb->data;
|
|
req->context = skb;
|
|
req->complete = tx_complete;
|
|
|
|
/* use zlp framing on tx for strict CDC-Ether conformance,
|
|
* though any robust network rx path ignores extra padding.
|
|
* and some hardware doesn't like to write zlps.
|
|
*/
|
|
req->zero = 1;
|
|
if (!dev->zlp && (length % in->maxpacket) == 0)
|
|
length++;
|
|
|
|
req->length = length;
|
|
|
|
/* throttle highspeed IRQ rate back slightly */
|
|
if (gadget_is_dualspeed(dev->gadget))
|
|
req->no_interrupt = (dev->gadget->speed == USB_SPEED_HIGH)
|
|
? ((atomic_read(&dev->tx_qlen) % qmult) != 0)
|
|
: 0;
|
|
|
|
retval = usb_ep_queue(in, req, GFP_ATOMIC);
|
|
switch (retval) {
|
|
default:
|
|
DBG(dev, "tx queue err %d\n", retval);
|
|
break;
|
|
case 0:
|
|
net->trans_start = jiffies;
|
|
atomic_inc(&dev->tx_qlen);
|
|
}
|
|
|
|
if (retval) {
|
|
drop:
|
|
dev->net->stats.tx_dropped++;
|
|
dev_kfree_skb_any(skb);
|
|
spin_lock_irqsave(&dev->req_lock, flags);
|
|
if (list_empty(&dev->tx_reqs))
|
|
netif_start_queue(net);
|
|
list_add(&req->list, &dev->tx_reqs);
|
|
spin_unlock_irqrestore(&dev->req_lock, flags);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
static void eth_start(struct eth_dev *dev, gfp_t gfp_flags)
|
|
{
|
|
DBG(dev, "%s\n", __func__);
|
|
|
|
/* fill the rx queue */
|
|
rx_fill(dev, gfp_flags);
|
|
|
|
/* and open the tx floodgates */
|
|
atomic_set(&dev->tx_qlen, 0);
|
|
netif_wake_queue(dev->net);
|
|
}
|
|
|
|
static int eth_open(struct net_device *net)
|
|
{
|
|
struct eth_dev *dev = netdev_priv(net);
|
|
struct gether *link;
|
|
|
|
DBG(dev, "%s\n", __func__);
|
|
if (netif_carrier_ok(dev->net))
|
|
eth_start(dev, GFP_KERNEL);
|
|
|
|
spin_lock_irq(&dev->lock);
|
|
link = dev->port_usb;
|
|
if (link && link->open)
|
|
link->open(link);
|
|
spin_unlock_irq(&dev->lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int eth_stop(struct net_device *net)
|
|
{
|
|
struct eth_dev *dev = netdev_priv(net);
|
|
unsigned long flags;
|
|
|
|
VDBG(dev, "%s\n", __func__);
|
|
netif_stop_queue(net);
|
|
|
|
DBG(dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld\n",
|
|
dev->net->stats.rx_packets, dev->net->stats.tx_packets,
|
|
dev->net->stats.rx_errors, dev->net->stats.tx_errors
|
|
);
|
|
|
|
/* ensure there are no more active requests */
|
|
spin_lock_irqsave(&dev->lock, flags);
|
|
if (dev->port_usb) {
|
|
struct gether *link = dev->port_usb;
|
|
|
|
if (link->close)
|
|
link->close(link);
|
|
|
|
/* NOTE: we have no abort-queue primitive we could use
|
|
* to cancel all pending I/O. Instead, we disable then
|
|
* reenable the endpoints ... this idiom may leave toggle
|
|
* wrong, but that's a self-correcting error.
|
|
*
|
|
* REVISIT: we *COULD* just let the transfers complete at
|
|
* their own pace; the network stack can handle old packets.
|
|
* For the moment we leave this here, since it works.
|
|
*/
|
|
usb_ep_disable(link->in_ep);
|
|
usb_ep_disable(link->out_ep);
|
|
if (netif_carrier_ok(net)) {
|
|
DBG(dev, "host still using in/out endpoints\n");
|
|
usb_ep_enable(link->in_ep, link->in);
|
|
usb_ep_enable(link->out_ep, link->out);
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&dev->lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/* initial value, changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx" */
|
|
static char *dev_addr;
|
|
module_param(dev_addr, charp, S_IRUGO);
|
|
MODULE_PARM_DESC(dev_addr, "Device Ethernet Address");
|
|
|
|
/* this address is invisible to ifconfig */
|
|
static char *host_addr;
|
|
module_param(host_addr, charp, S_IRUGO);
|
|
MODULE_PARM_DESC(host_addr, "Host Ethernet Address");
|
|
|
|
|
|
static u8 __init nibble(unsigned char c)
|
|
{
|
|
if (isdigit(c))
|
|
return c - '0';
|
|
c = toupper(c);
|
|
if (isxdigit(c))
|
|
return 10 + c - 'A';
|
|
return 0;
|
|
}
|
|
|
|
static int __init get_ether_addr(const char *str, u8 *dev_addr)
|
|
{
|
|
if (str) {
|
|
unsigned i;
|
|
|
|
for (i = 0; i < 6; i++) {
|
|
unsigned char num;
|
|
|
|
if ((*str == '.') || (*str == ':'))
|
|
str++;
|
|
num = nibble(*str++) << 4;
|
|
num |= (nibble(*str++));
|
|
dev_addr [i] = num;
|
|
}
|
|
if (is_valid_ether_addr(dev_addr))
|
|
return 0;
|
|
}
|
|
random_ether_addr(dev_addr);
|
|
return 1;
|
|
}
|
|
|
|
static struct eth_dev *the_dev;
|
|
|
|
static const struct net_device_ops eth_netdev_ops = {
|
|
.ndo_open = eth_open,
|
|
.ndo_stop = eth_stop,
|
|
.ndo_start_xmit = eth_start_xmit,
|
|
.ndo_change_mtu = ueth_change_mtu,
|
|
.ndo_set_mac_address = eth_mac_addr,
|
|
.ndo_validate_addr = eth_validate_addr,
|
|
};
|
|
|
|
/**
|
|
* gether_setup - initialize one ethernet-over-usb link
|
|
* @g: gadget to associated with these links
|
|
* @ethaddr: NULL, or a buffer in which the ethernet address of the
|
|
* host side of the link is recorded
|
|
* Context: may sleep
|
|
*
|
|
* This sets up the single network link that may be exported by a
|
|
* gadget driver using this framework. The link layer addresses are
|
|
* set up using module parameters.
|
|
*
|
|
* Returns negative errno, or zero on success
|
|
*/
|
|
int __init gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN])
|
|
{
|
|
struct eth_dev *dev;
|
|
struct net_device *net;
|
|
int status;
|
|
|
|
if (the_dev)
|
|
return -EBUSY;
|
|
|
|
net = alloc_etherdev(sizeof *dev);
|
|
if (!net)
|
|
return -ENOMEM;
|
|
|
|
dev = netdev_priv(net);
|
|
spin_lock_init(&dev->lock);
|
|
spin_lock_init(&dev->req_lock);
|
|
INIT_WORK(&dev->work, eth_work);
|
|
INIT_LIST_HEAD(&dev->tx_reqs);
|
|
INIT_LIST_HEAD(&dev->rx_reqs);
|
|
|
|
/* network device setup */
|
|
dev->net = net;
|
|
strcpy(net->name, "usb%d");
|
|
|
|
if (get_ether_addr(dev_addr, net->dev_addr))
|
|
dev_warn(&g->dev,
|
|
"using random %s ethernet address\n", "self");
|
|
if (get_ether_addr(host_addr, dev->host_mac))
|
|
dev_warn(&g->dev,
|
|
"using random %s ethernet address\n", "host");
|
|
|
|
if (ethaddr)
|
|
memcpy(ethaddr, dev->host_mac, ETH_ALEN);
|
|
|
|
net->netdev_ops = ð_netdev_ops;
|
|
|
|
SET_ETHTOOL_OPS(net, &ops);
|
|
|
|
/* two kinds of host-initiated state changes:
|
|
* - iff DATA transfer is active, carrier is "on"
|
|
* - tx queueing enabled if open *and* carrier is "on"
|
|
*/
|
|
netif_stop_queue(net);
|
|
netif_carrier_off(net);
|
|
|
|
dev->gadget = g;
|
|
SET_NETDEV_DEV(net, &g->dev);
|
|
|
|
status = register_netdev(net);
|
|
if (status < 0) {
|
|
dev_dbg(&g->dev, "register_netdev failed, %d\n", status);
|
|
free_netdev(net);
|
|
} else {
|
|
INFO(dev, "MAC %pM\n", net->dev_addr);
|
|
INFO(dev, "HOST MAC %pM\n", dev->host_mac);
|
|
|
|
the_dev = dev;
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
/**
|
|
* gether_cleanup - remove Ethernet-over-USB device
|
|
* Context: may sleep
|
|
*
|
|
* This is called to free all resources allocated by @gether_setup().
|
|
*/
|
|
void gether_cleanup(void)
|
|
{
|
|
if (!the_dev)
|
|
return;
|
|
|
|
unregister_netdev(the_dev->net);
|
|
free_netdev(the_dev->net);
|
|
|
|
/* assuming we used keventd, it must quiesce too */
|
|
flush_scheduled_work();
|
|
|
|
the_dev = NULL;
|
|
}
|
|
|
|
|
|
/**
|
|
* gether_connect - notify network layer that USB link is active
|
|
* @link: the USB link, set up with endpoints, descriptors matching
|
|
* current device speed, and any framing wrapper(s) set up.
|
|
* Context: irqs blocked
|
|
*
|
|
* This is called to activate endpoints and let the network layer know
|
|
* the connection is active ("carrier detect"). It may cause the I/O
|
|
* queues to open and start letting network packets flow, but will in
|
|
* any case activate the endpoints so that they respond properly to the
|
|
* USB host.
|
|
*
|
|
* Verify net_device pointer returned using IS_ERR(). If it doesn't
|
|
* indicate some error code (negative errno), ep->driver_data values
|
|
* have been overwritten.
|
|
*/
|
|
struct net_device *gether_connect(struct gether *link)
|
|
{
|
|
struct eth_dev *dev = the_dev;
|
|
int result = 0;
|
|
|
|
if (!dev)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
link->in_ep->driver_data = dev;
|
|
result = usb_ep_enable(link->in_ep, link->in);
|
|
if (result != 0) {
|
|
DBG(dev, "enable %s --> %d\n",
|
|
link->in_ep->name, result);
|
|
goto fail0;
|
|
}
|
|
|
|
link->out_ep->driver_data = dev;
|
|
result = usb_ep_enable(link->out_ep, link->out);
|
|
if (result != 0) {
|
|
DBG(dev, "enable %s --> %d\n",
|
|
link->out_ep->name, result);
|
|
goto fail1;
|
|
}
|
|
|
|
if (result == 0)
|
|
result = alloc_requests(dev, link, qlen(dev->gadget));
|
|
|
|
if (result == 0) {
|
|
dev->zlp = link->is_zlp_ok;
|
|
DBG(dev, "qlen %d\n", qlen(dev->gadget));
|
|
|
|
dev->header_len = link->header_len;
|
|
dev->unwrap = link->unwrap;
|
|
dev->wrap = link->wrap;
|
|
|
|
spin_lock(&dev->lock);
|
|
dev->port_usb = link;
|
|
link->ioport = dev;
|
|
if (netif_running(dev->net)) {
|
|
if (link->open)
|
|
link->open(link);
|
|
} else {
|
|
if (link->close)
|
|
link->close(link);
|
|
}
|
|
spin_unlock(&dev->lock);
|
|
|
|
netif_carrier_on(dev->net);
|
|
if (netif_running(dev->net))
|
|
eth_start(dev, GFP_ATOMIC);
|
|
|
|
/* on error, disable any endpoints */
|
|
} else {
|
|
(void) usb_ep_disable(link->out_ep);
|
|
fail1:
|
|
(void) usb_ep_disable(link->in_ep);
|
|
}
|
|
fail0:
|
|
/* caller is responsible for cleanup on error */
|
|
if (result < 0)
|
|
return ERR_PTR(result);
|
|
return dev->net;
|
|
}
|
|
|
|
/**
|
|
* gether_disconnect - notify network layer that USB link is inactive
|
|
* @link: the USB link, on which gether_connect() was called
|
|
* Context: irqs blocked
|
|
*
|
|
* This is called to deactivate endpoints and let the network layer know
|
|
* the connection went inactive ("no carrier").
|
|
*
|
|
* On return, the state is as if gether_connect() had never been called.
|
|
* The endpoints are inactive, and accordingly without active USB I/O.
|
|
* Pointers to endpoint descriptors and endpoint private data are nulled.
|
|
*/
|
|
void gether_disconnect(struct gether *link)
|
|
{
|
|
struct eth_dev *dev = link->ioport;
|
|
struct usb_request *req;
|
|
|
|
WARN_ON(!dev);
|
|
if (!dev)
|
|
return;
|
|
|
|
DBG(dev, "%s\n", __func__);
|
|
|
|
netif_stop_queue(dev->net);
|
|
netif_carrier_off(dev->net);
|
|
|
|
/* disable endpoints, forcing (synchronous) completion
|
|
* of all pending i/o. then free the request objects
|
|
* and forget about the endpoints.
|
|
*/
|
|
usb_ep_disable(link->in_ep);
|
|
spin_lock(&dev->req_lock);
|
|
while (!list_empty(&dev->tx_reqs)) {
|
|
req = container_of(dev->tx_reqs.next,
|
|
struct usb_request, list);
|
|
list_del(&req->list);
|
|
|
|
spin_unlock(&dev->req_lock);
|
|
usb_ep_free_request(link->in_ep, req);
|
|
spin_lock(&dev->req_lock);
|
|
}
|
|
spin_unlock(&dev->req_lock);
|
|
link->in_ep->driver_data = NULL;
|
|
link->in = NULL;
|
|
|
|
usb_ep_disable(link->out_ep);
|
|
spin_lock(&dev->req_lock);
|
|
while (!list_empty(&dev->rx_reqs)) {
|
|
req = container_of(dev->rx_reqs.next,
|
|
struct usb_request, list);
|
|
list_del(&req->list);
|
|
|
|
spin_unlock(&dev->req_lock);
|
|
usb_ep_free_request(link->out_ep, req);
|
|
spin_lock(&dev->req_lock);
|
|
}
|
|
spin_unlock(&dev->req_lock);
|
|
link->out_ep->driver_data = NULL;
|
|
link->out = NULL;
|
|
|
|
/* finish forgetting about this USB link episode */
|
|
dev->header_len = 0;
|
|
dev->unwrap = NULL;
|
|
dev->wrap = NULL;
|
|
|
|
spin_lock(&dev->lock);
|
|
dev->port_usb = NULL;
|
|
link->ioport = NULL;
|
|
spin_unlock(&dev->lock);
|
|
}
|