treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / arch / m68k / emu / nfeth.c
blobd2875e32abfca96f9f043d366b568e2061a5fb99
1 /*
2 * atari_nfeth.c - ARAnyM ethernet card driver for GNU/Linux
4 * Copyright (c) 2005 Milan Jurik, Petr Stehlik of ARAnyM dev team
6 * Based on ARAnyM driver for FreeMiNT written by Standa Opichal
8 * This software may be used and distributed according to the terms of
9 * the GNU General Public License (GPL), incorporated herein by reference.
12 #define DRV_VERSION "0.3"
13 #define DRV_RELDATE "10/12/2005"
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21 #include <asm/natfeat.h>
22 #include <asm/virtconvert.h>
24 enum {
25 GET_VERSION = 0,/* no parameters, return NFAPI_VERSION in d0 */
26 XIF_INTLEVEL, /* no parameters, return Interrupt Level in d0 */
27 XIF_IRQ, /* acknowledge interrupt from host */
28 XIF_START, /* (ethX), called on 'ifup', start receiver thread */
29 XIF_STOP, /* (ethX), called on 'ifdown', stop the thread */
30 XIF_READLENGTH, /* (ethX), return size of network data block to read */
31 XIF_READBLOCK, /* (ethX, buffer, size), read block of network data */
32 XIF_WRITEBLOCK, /* (ethX, buffer, size), write block of network data */
33 XIF_GET_MAC, /* (ethX, buffer, size), return MAC HW addr in buffer */
34 XIF_GET_IPHOST, /* (ethX, buffer, size), return IP address of host */
35 XIF_GET_IPATARI,/* (ethX, buffer, size), return IP address of atari */
36 XIF_GET_NETMASK /* (ethX, buffer, size), return IP netmask */
39 #define MAX_UNIT 8
41 /* These identify the driver base version and may not be removed. */
42 static const char version[] =
43 KERN_INFO KBUILD_MODNAME ".c:v" DRV_VERSION " " DRV_RELDATE
44 " S.Opichal, M.Jurik, P.Stehlik\n"
45 KERN_INFO " http://aranym.org/\n";
47 MODULE_AUTHOR("Milan Jurik");
48 MODULE_DESCRIPTION("Atari NFeth driver");
49 MODULE_LICENSE("GPL");
52 static long nfEtherID;
53 static int nfEtherIRQ;
55 struct nfeth_private {
56 int ethX;
59 static struct net_device *nfeth_dev[MAX_UNIT];
61 static int nfeth_open(struct net_device *dev)
63 struct nfeth_private *priv = netdev_priv(dev);
64 int res;
66 res = nf_call(nfEtherID + XIF_START, priv->ethX);
67 netdev_dbg(dev, "%s: %d\n", __func__, res);
69 /* Ready for data */
70 netif_start_queue(dev);
72 return 0;
75 static int nfeth_stop(struct net_device *dev)
77 struct nfeth_private *priv = netdev_priv(dev);
79 /* No more data */
80 netif_stop_queue(dev);
82 nf_call(nfEtherID + XIF_STOP, priv->ethX);
84 return 0;
88 * Read a packet out of the adapter and pass it to the upper layers
90 static inline void recv_packet(struct net_device *dev)
92 struct nfeth_private *priv = netdev_priv(dev);
93 unsigned short pktlen;
94 struct sk_buff *skb;
96 /* read packet length (excluding 32 bit crc) */
97 pktlen = nf_call(nfEtherID + XIF_READLENGTH, priv->ethX);
99 netdev_dbg(dev, "%s: %u\n", __func__, pktlen);
101 if (!pktlen) {
102 netdev_dbg(dev, "%s: pktlen == 0\n", __func__);
103 dev->stats.rx_errors++;
104 return;
107 skb = dev_alloc_skb(pktlen + 2);
108 if (!skb) {
109 netdev_dbg(dev, "%s: out of mem (buf_alloc failed)\n",
110 __func__);
111 dev->stats.rx_dropped++;
112 return;
115 skb->dev = dev;
116 skb_reserve(skb, 2); /* 16 Byte align */
117 skb_put(skb, pktlen); /* make room */
118 nf_call(nfEtherID + XIF_READBLOCK, priv->ethX, virt_to_phys(skb->data),
119 pktlen);
121 skb->protocol = eth_type_trans(skb, dev);
122 netif_rx(skb);
123 dev->stats.rx_packets++;
124 dev->stats.rx_bytes += pktlen;
126 /* and enqueue packet */
127 return;
130 static irqreturn_t nfeth_interrupt(int irq, void *dev_id)
132 int i, m, mask;
134 mask = nf_call(nfEtherID + XIF_IRQ, 0);
135 for (i = 0, m = 1; i < MAX_UNIT; m <<= 1, i++) {
136 if (mask & m && nfeth_dev[i]) {
137 recv_packet(nfeth_dev[i]);
138 nf_call(nfEtherID + XIF_IRQ, m);
141 return IRQ_HANDLED;
144 static int nfeth_xmit(struct sk_buff *skb, struct net_device *dev)
146 unsigned int len;
147 char *data, shortpkt[ETH_ZLEN];
148 struct nfeth_private *priv = netdev_priv(dev);
150 data = skb->data;
151 len = skb->len;
152 if (len < ETH_ZLEN) {
153 memset(shortpkt, 0, ETH_ZLEN);
154 memcpy(shortpkt, data, len);
155 data = shortpkt;
156 len = ETH_ZLEN;
159 netdev_dbg(dev, "%s: send %u bytes\n", __func__, len);
160 nf_call(nfEtherID + XIF_WRITEBLOCK, priv->ethX, virt_to_phys(data),
161 len);
163 dev->stats.tx_packets++;
164 dev->stats.tx_bytes += len;
166 dev_kfree_skb(skb);
167 return 0;
170 static void nfeth_tx_timeout(struct net_device *dev, unsigned int txqueue)
172 dev->stats.tx_errors++;
173 netif_wake_queue(dev);
176 static const struct net_device_ops nfeth_netdev_ops = {
177 .ndo_open = nfeth_open,
178 .ndo_stop = nfeth_stop,
179 .ndo_start_xmit = nfeth_xmit,
180 .ndo_tx_timeout = nfeth_tx_timeout,
181 .ndo_validate_addr = eth_validate_addr,
182 .ndo_set_mac_address = eth_mac_addr,
185 static struct net_device * __init nfeth_probe(int unit)
187 struct net_device *dev;
188 struct nfeth_private *priv;
189 char mac[ETH_ALEN], host_ip[32], local_ip[32];
190 int err;
192 if (!nf_call(nfEtherID + XIF_GET_MAC, unit, virt_to_phys(mac),
193 ETH_ALEN))
194 return NULL;
196 dev = alloc_etherdev(sizeof(struct nfeth_private));
197 if (!dev)
198 return NULL;
200 dev->irq = nfEtherIRQ;
201 dev->netdev_ops = &nfeth_netdev_ops;
203 memcpy(dev->dev_addr, mac, ETH_ALEN);
205 priv = netdev_priv(dev);
206 priv->ethX = unit;
208 err = register_netdev(dev);
209 if (err) {
210 free_netdev(dev);
211 return NULL;
214 nf_call(nfEtherID + XIF_GET_IPHOST, unit,
215 virt_to_phys(host_ip), sizeof(host_ip));
216 nf_call(nfEtherID + XIF_GET_IPATARI, unit,
217 virt_to_phys(local_ip), sizeof(local_ip));
219 netdev_info(dev, KBUILD_MODNAME " addr:%s (%s) HWaddr:%pM\n", host_ip,
220 local_ip, mac);
222 return dev;
225 static int __init nfeth_init(void)
227 long ver;
228 int error, i;
230 nfEtherID = nf_get_id("ETHERNET");
231 if (!nfEtherID)
232 return -ENODEV;
234 ver = nf_call(nfEtherID + GET_VERSION);
235 pr_info("API %lu\n", ver);
237 nfEtherIRQ = nf_call(nfEtherID + XIF_INTLEVEL);
238 error = request_irq(nfEtherIRQ, nfeth_interrupt, IRQF_SHARED,
239 "eth emu", nfeth_interrupt);
240 if (error) {
241 pr_err("request for irq %d failed %d", nfEtherIRQ, error);
242 return error;
245 for (i = 0; i < MAX_UNIT; i++)
246 nfeth_dev[i] = nfeth_probe(i);
248 return 0;
251 static void __exit nfeth_cleanup(void)
253 int i;
255 for (i = 0; i < MAX_UNIT; i++) {
256 if (nfeth_dev[i]) {
257 unregister_netdev(nfeth_dev[0]);
258 free_netdev(nfeth_dev[0]);
261 free_irq(nfEtherIRQ, nfeth_interrupt);
264 module_init(nfeth_init);
265 module_exit(nfeth_cleanup);