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|
/*
* phonet.c -- USB CDC Phonet host driver
*
* Copyright (C) 2008-2009 Nokia Corporation. All rights reserved.
*
* Author: Rémi Denis-Courmont
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* 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., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/if_phonet.h>
#include <linux/phonet.h>
#define PN_MEDIA_USB 0x1B
static const unsigned rxq_size = 17;
struct usbpn_dev {
struct net_device *dev;
struct usb_interface *intf, *data_intf;
struct usb_device *usb;
unsigned int tx_pipe, rx_pipe;
u8 active_setting;
u8 disconnected;
unsigned tx_queue;
spinlock_t tx_lock;
spinlock_t rx_lock;
struct sk_buff *rx_skb;
struct urb *urbs[0];
};
static void tx_complete(struct urb *req);
static void rx_complete(struct urb *req);
/*
* Network device callbacks
*/
static netdev_tx_t usbpn_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct usbpn_dev *pnd = netdev_priv(dev);
struct urb *req = NULL;
unsigned long flags;
int err;
if (skb->protocol != htons(ETH_P_PHONET))
goto drop;
req = usb_alloc_urb(0, GFP_ATOMIC);
if (!req)
goto drop;
usb_fill_bulk_urb(req, pnd->usb, pnd->tx_pipe, skb->data, skb->len,
tx_complete, skb);
req->transfer_flags = URB_ZERO_PACKET;
err = usb_submit_urb(req, GFP_ATOMIC);
if (err) {
usb_free_urb(req);
goto drop;
}
spin_lock_irqsave(&pnd->tx_lock, flags);
pnd->tx_queue++;
if (pnd->tx_queue >= dev->tx_queue_len)
netif_stop_queue(dev);
spin_unlock_irqrestore(&pnd->tx_lock, flags);
return NETDEV_TX_OK;
drop:
dev_kfree_skb(skb);
dev->stats.tx_dropped++;
return NETDEV_TX_OK;
}
static void tx_complete(struct urb *req)
{
struct sk_buff *skb = req->context;
struct net_device *dev = skb->dev;
struct usbpn_dev *pnd = netdev_priv(dev);
int status = req->status;
switch (status) {
case 0:
dev->stats.tx_bytes += skb->len;
break;
case -ENOENT:
case -ECONNRESET:
case -ESHUTDOWN:
dev->stats.tx_aborted_errors++;
default:
dev->stats.tx_errors++;
dev_dbg(&dev->dev, "TX error (%d)\n", status);
}
dev->stats.tx_packets++;
spin_lock(&pnd->tx_lock);
pnd->tx_queue--;
netif_wake_queue(dev);
spin_unlock(&pnd->tx_lock);
dev_kfree_skb_any(skb);
usb_free_urb(req);
}
static int rx_submit(struct usbpn_dev *pnd, struct urb *req, gfp_t gfp_flags)
{
struct net_device *dev = pnd->dev;
struct page *page;
int err;
page = __dev_alloc_page(gfp_flags | __GFP_NOMEMALLOC);
if (!page)
return -ENOMEM;
usb_fill_bulk_urb(req, pnd->usb, pnd->rx_pipe, page_address(page),
PAGE_SIZE, rx_complete, dev);
req->transfer_flags = 0;
err = usb_submit_urb(req, gfp_flags);
if (unlikely(err)) {
dev_dbg(&dev->dev, "RX submit error (%d)\n", err);
put_page(page);
}
return err;
}
static void rx_complete(struct urb *req)
{
struct net_device *dev = req->context;
struct usbpn_dev *pnd = netdev_priv(dev);
struct page *page = virt_to_page(req->transfer_buffer);
struct sk_buff *skb;
unsigned long flags;
int status = req->status;
switch (status) {
case 0:
spin_lock_irqsave(&pnd->rx_lock, flags);
skb = pnd->rx_skb;
if (!skb) {
skb = pnd->rx_skb = netdev_alloc_skb(dev, 12);
if (likely(skb)) {
/* Can't use pskb_pull() on page in IRQ */
skb_put_data(skb, page_address(page), 1);
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
page, 1, req->actual_length,
PAGE_SIZE);
page = NULL;
}
} else {
skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
page, 0, req->actual_length,
PAGE_SIZE);
page = NULL;
}
if (req->actual_length < PAGE_SIZE)
pnd->rx_skb = NULL; /* Last fragment */
else
skb = NULL;
spin_unlock_irqrestore(&pnd->rx_lock, flags);
if (skb) {
skb->protocol = htons(ETH_P_PHONET);
skb_reset_mac_header(skb);
__skb_pull(skb, 1);
skb->dev = dev;
dev->stats.rx_packets++;
dev->stats.rx_bytes += skb->len;
netif_rx(skb);
}
goto resubmit;
case -ENOENT:
case -ECONNRESET:
case -ESHUTDOWN:
req = NULL;
break;
case -EOVERFLOW:
dev->stats.rx_over_errors++;
dev_dbg(&dev->dev, "RX overflow\n");
break;
case -EILSEQ:
dev->stats.rx_crc_errors++;
break;
}
dev->stats.rx_errors++;
resubmit:
if (page)
put_page(page);
if (req)
rx_submit(pnd, req, GFP_ATOMIC);
}
static int usbpn_close(struct net_device *dev);
static int usbpn_open(struct net_device *dev)
{
struct usbpn_dev *pnd = netdev_priv(dev);
int err;
unsigned i;
unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber;
err = usb_set_interface(pnd->usb, num, pnd->active_setting);
if (err)
return err;
for (i = 0; i < rxq_size; i++) {
struct urb *req = usb_alloc_urb(0, GFP_KERNEL);
if (!req || rx_submit(pnd, req, GFP_KERNEL)) {
usb_free_urb(req);
usbpn_close(dev);
return -ENOMEM;
}
pnd->urbs[i] = req;
}
netif_wake_queue(dev);
return 0;
}
static int usbpn_close(struct net_device *dev)
{
struct usbpn_dev *pnd = netdev_priv(dev);
unsigned i;
unsigned num = pnd->data_intf->cur_altsetting->desc.bInterfaceNumber;
netif_stop_queue(dev);
for (i =
|