/* $Id: hysdn_net.c,v 1.8.6.4 2001/09/23 22:24:54 kai Exp $
*
* Linux driver for HYSDN cards, net (ethernet type) handling routines.
*
* Author Werner Cornelius (werner@titro.de) for Hypercope GmbH
* Copyright 1999 by Werner Cornelius (werner@titro.de)
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*
* This net module has been inspired by the skeleton driver from
* Donald Becker (becker@CESDIS.gsfc.nasa.gov)
*
*/
#include <linux/module.h>
#include <linux/signal.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/inetdevice.h>
#include "hysdn_defs.h"
unsigned int hynet_enable = 0xffffffff;
module_param(hynet_enable, uint, 0);
#define MAX_SKB_BUFFERS 20 /* number of buffers for keeping TX-data */
/****************************************************************************/
/* structure containing the complete network data. The structure is aligned */
/* in a way that both, the device and statistics are kept inside it. */
/* for proper access, the device structure MUST be the first var/struct */
/* inside the definition. */
/****************************************************************************/
struct net_local {
/* Tx control lock. This protects the transmit buffer ring
* state along with the "tx full" state of the driver. This
* means all netif_queue flow control actions are protected
* by this lock as well.
*/
struct net_device *dev;
spinlock_t lock;
struct sk_buff *skbs[MAX_SKB_BUFFERS]; /* pointers to tx-skbs */
int in_idx, out_idx; /* indexes to buffer ring */
int sk_count; /* number of buffers currently in ring */
}; /* net_local */
/*********************************************************************/
/* Open/initialize the board. This is called (in the current kernel) */
/* sometime after booting when the 'ifconfig' program is run. */
/* This routine should set everything up anew at each open, even */
/* registers that "should" only need to be set once at boot, so that */
/* there is non-reboot way to recover if something goes wrong. */
/*********************************************************************/
static int
net_open(struct net_device *dev)
{
struct in_device *in_dev;
hysdn_card *card = dev->ml_priv;
int i;
netif_start_queue(dev); /* start tx-queueing */
/* Fill in the MAC-level header (if not already set) */
if (!card->mac_addr[0]) {
for (i = 0; i < ETH_ALEN; i++)
dev->dev_addr[i] = 0xfc;
if ((in_dev = dev->ip_ptr) != NULL) {
struct in_ifaddr *ifa = in_dev->ifa_list;
if (ifa != NULL)
memcpy(dev->dev_addr + (ETH_ALEN - sizeof(ifa->ifa_local)), &ifa->ifa_local, sizeof(ifa->ifa_local));
}
} else
memcpy(dev->dev_addr, card->mac_addr, ETH_ALEN);
return (0);
} /* net_open */
/*******************************************/
/* flush the currently occupied tx-buffers */
/* must only be called when device closed */
/*******************************************/
static void
flush_tx_buffers(struct net_local *nl)
{
while (nl->sk_count) {
dev_kfree_skb(nl->skbs[nl->out_idx++]); /* free skb */
if (nl->out_idx >= MAX_SKB_BUFFERS)
nl->out_idx = 0; /* wrap around */
nl->sk_count--;
}
} /* flush_tx_buffers */
/*********************************************************************/
/* close/decativate the device. The device is not removed, but only */
/* deactivated. */
/*********************************************************************/
static int
net_close(struct net_device *dev)
{
netif_stop_queue(dev); /* disable queueing */
flush_tx_buffers((struct net_local *) dev);
return (0); /* success */
} /* net_close */
/************************************/
/* send a packet on this interface. */
/* new style for kernel >= 2.3.33 */
/************************************/
static netdev_tx_t
net_send_packet(struct sk_buff *skb, struct net_device *dev)
{
struct net_local *lp = (struct net_local *) dev;
spin_lock_irq(&lp->lock);
lp->skbs[lp->in_idx++] = skb; /* add to buffer list */
if (lp->in_idx >= MAX_SKB_BUFFERS)
lp->in_idx = 0; /* wrap around */
lp->sk_count++; /* adjust counter */
dev->trans_start = jiffies;
/* If we just used up the very last entry in the
* TX ring on this device, tell the queueing
* layer to send no more.
*/
if (lp->sk_count >= MAX_SKB_BUFFERS)
netif_stop_queue(dev);
/* When the TX completion hw interrupt arrives, this
* is when the transmit statistics are updated.
*/
spin_unlock_irq(&lp->lock);
if (lp->sk_count <= 3) {
schedule_work(&((hysdn_card *) dev->ml_priv)->irq_queue);
}
return NETDEV_TX_OK; /* success */
} /* net_send_packet */
/***********************************************************************/
/* acknowlegde a packet send. The network layer will be informed about */
/* completion */
/***********************************************************************/
void
hysdn_tx_netack(hysdn_card *card)
{
struct net_local *lp = card->netif;
if (!lp)
return; /* non existing device */
if (!lp->sk_count)
return; /* error condition */
lp->dev->stats.tx_packets++;
lp->dev->stats.tx_bytes += lp->skbs[lp->out_idx]->len;
dev_kfree_skb(lp->skbs[lp->out_idx++]); /* free skb */
if (lp->out_idx >= MAX_SKB_BUFFERS)
lp->out_idx = 0; /* wrap around */
if (lp->sk_count-- == MAX_SKB_BUFFERS) /* dec usage count */
netif_start_queue((struct net_device *) lp);
} /* hysdn_tx_netack */
/*****************************************************/
/* we got a packet from the network, go and queue it */
/*****************************************************/
void
hysdn_rx_netpkt(hysdn_card *card, unsigned char *buf, unsigned short len)
{
struct net_local *lp = card->netif;
struct net_device *dev;
struct sk_buff *skb;
if (!lp)
return; /* non existing device */
dev = lp->dev;
dev->stats.rx_bytes += len;
skb = dev_alloc_skb(len);
if (skb == NULL) {
printk(KERN_NOTICE "%s: Memory squeeze, dropping packet.\n",
dev->name);
dev->stats.rx_dropped++;
return;
}
/* copy the data */
memcpy(skb_put(skb, len), buf, len);
/* determine the used protocol */
skb->protocol = eth_type_trans(skb, dev);
dev->stats.rx_packets++; /* adjust packet count */
netif_rx(skb);
} /* hysdn_rx_netpkt */
/*****************************************************/
/* return the pointer to a network packet to be send */
/*****************************************************/
struct sk_buff *
hysdn_tx_netget(hysdn_card *card)
{
struct net_local *lp = card->netif;
if (!lp)
return (NULL); /* non existing device */
if (!lp->sk_count)
return (NULL); /* nothing available */
return (lp->skbs[lp->out_idx]); /* next packet to send */
} /* hysdn_tx_netget */
static const struct net_device_ops hysdn_netdev_ops = {
.ndo_open = net_open,
.ndo_stop = net_close,
.ndo_start_xmit = net_send_packet,
.ndo_change_mtu = eth_change_mtu,
.ndo_set_mac_address = eth_mac_addr,
.ndo_validate_addr = eth_validate_addr,
};
/*****************************************************************************/
/* hysdn_net_create creates a new net device for the given card. If a device */
/* already exists, it will be deleted and created a new one. The return value */
/* 0 announces success, else a negative error code will be returned. */
/*****************************************************************************/
int
hysdn_net_create(hysdn_card *card)
{
struct net_device *dev;
int i;
struct net_local *lp;
if (!card) {
printk(KERN_WARNING "No card-pt in hysdn_net_create!\n");
return (-ENOMEM);
}
hysdn_net_release(card); /* release an existing net device */
dev = alloc_etherdev(sizeof(struct net_local));
if (!dev) {
printk(KERN_WARNING "HYSDN: unable to allocate mem\n");
return (-ENOMEM);
}
lp = netdev_priv(dev);
lp->dev = dev;
dev->netdev_ops = &hysdn_netdev_ops;
spin_lock_init(&((struct net_local *) dev)->lock);
/* initialise necessary or informing fields */
dev->base_addr = card->iobase; /* IO address */
dev->irq = card->irq; /* irq */
dev->netdev_ops = &hysdn_netdev_ops;
if ((i = register_netdev(dev))) {
printk(KERN_WARNING "HYSDN: unable to create network device\n");
free_netdev(dev);
return (i);
}
dev->ml_priv = card; /* remember pointer to own data structure */
card->netif = dev; /* setup the local pointer */
if (card->debug_flags & LOG_NET_INIT)
hysdn_addlog(card, "network device created");
return (0); /* and return success */
} /* hysdn_net_create */
/***************************************************************************/
/* hysdn_net_release deletes the net device for the given card. The return */
/* value 0 announces success, else a negative error code will be returned. */
/***************************************************************************/
int
hysdn_net_release(hysdn_card *card)
{
struct net_device *dev = card->netif;
if (!dev)
return (0); /* non existing */
card->netif = NULL; /* clear out pointer */
net_close(dev);
flush_tx_buffers((struct net_local *) dev); /* empty buffers */
unregister_netdev(dev); /* release the device */
free_netdev(dev); /* release the memory allocated */
if (card->debug_flags & LOG_NET_INIT)
hysdn_addlog(card, "network device deleted");
return (0); /* always successful */
} /* hysdn_net_release */
/*****************************************************************************/
/* hysdn_net_getname returns a pointer to the name of the network interface. */
/* if the interface is not existing, a "-" is returned. */
/*****************************************************************************/
char *
hysdn_net_getname(hysdn_card *card)
{
struct net_device *dev = card->netif;
if (!dev)
return ("-"); /* non existing */
return (dev->name);
} /* hysdn_net_getname */