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path: root/drivers/net/plip/plip.c
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Diffstat (limited to 'drivers/net/plip/plip.c')
-rw-r--r--drivers/net/plip/plip.c1403
1 files changed, 1403 insertions, 0 deletions
diff --git a/drivers/net/plip/plip.c b/drivers/net/plip/plip.c
new file mode 100644
index 000000000000..a9e9ca8a86ed
--- /dev/null
+++ b/drivers/net/plip/plip.c
@@ -0,0 +1,1403 @@
+/* $Id: plip.c,v 1.3.6.2 1997/04/16 15:07:56 phil Exp $ */
+/* PLIP: A parallel port "network" driver for Linux. */
+/* This driver is for parallel port with 5-bit cable (LapLink (R) cable). */
+/*
+ * Authors: Donald Becker <becker@scyld.com>
+ * Tommy Thorn <thorn@daimi.aau.dk>
+ * Tanabe Hiroyasu <hiro@sanpo.t.u-tokyo.ac.jp>
+ * Alan Cox <gw4pts@gw4pts.ampr.org>
+ * Peter Bauer <100136.3530@compuserve.com>
+ * Niibe Yutaka <gniibe@mri.co.jp>
+ * Nimrod Zimerman <zimerman@mailandnews.com>
+ *
+ * Enhancements:
+ * Modularization and ifreq/ifmap support by Alan Cox.
+ * Rewritten by Niibe Yutaka.
+ * parport-sharing awareness code by Philip Blundell.
+ * SMP locking by Niibe Yutaka.
+ * Support for parallel ports with no IRQ (poll mode),
+ * Modifications to use the parallel port API
+ * by Nimrod Zimerman.
+ *
+ * Fixes:
+ * Niibe Yutaka
+ * - Module initialization.
+ * - MTU fix.
+ * - Make sure other end is OK, before sending a packet.
+ * - Fix immediate timer problem.
+ *
+ * Al Viro
+ * - Changed {enable,disable}_irq handling to make it work
+ * with new ("stack") semantics.
+ *
+ * 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.
+ */
+
+/*
+ * Original version and the name 'PLIP' from Donald Becker <becker@scyld.com>
+ * inspired by Russ Nelson's parallel port packet driver.
+ *
+ * NOTE:
+ * Tanabe Hiroyasu had changed the protocol, and it was in Linux v1.0.
+ * Because of the necessity to communicate to DOS machines with the
+ * Crynwr packet driver, Peter Bauer changed the protocol again
+ * back to original protocol.
+ *
+ * This version follows original PLIP protocol.
+ * So, this PLIP can't communicate the PLIP of Linux v1.0.
+ */
+
+/*
+ * To use with DOS box, please do (Turn on ARP switch):
+ * # ifconfig plip[0-2] arp
+ */
+static const char version[] = "NET3 PLIP version 2.4-parport gniibe@mri.co.jp\n";
+
+/*
+ Sources:
+ Ideas and protocols came from Russ Nelson's <nelson@crynwr.com>
+ "parallel.asm" parallel port packet driver.
+
+ The "Crynwr" parallel port standard specifies the following protocol:
+ Trigger by sending nibble '0x8' (this causes interrupt on other end)
+ count-low octet
+ count-high octet
+ ... data octets
+ checksum octet
+ Each octet is sent as <wait for rx. '0x1?'> <send 0x10+(octet&0x0F)>
+ <wait for rx. '0x0?'> <send 0x00+((octet>>4)&0x0F)>
+
+ The packet is encapsulated as if it were ethernet.
+
+ The cable used is a de facto standard parallel null cable -- sold as
+ a "LapLink" cable by various places. You'll need a 12-conductor cable to
+ make one yourself. The wiring is:
+ SLCTIN 17 - 17
+ GROUND 25 - 25
+ D0->ERROR 2 - 15 15 - 2
+ D1->SLCT 3 - 13 13 - 3
+ D2->PAPOUT 4 - 12 12 - 4
+ D3->ACK 5 - 10 10 - 5
+ D4->BUSY 6 - 11 11 - 6
+ Do not connect the other pins. They are
+ D5,D6,D7 are 7,8,9
+ STROBE is 1, FEED is 14, INIT is 16
+ extra grounds are 18,19,20,21,22,23,24
+*/
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/skbuff.h>
+#include <linux/if_plip.h>
+#include <linux/workqueue.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/parport.h>
+#include <linux/bitops.h>
+
+#include <net/neighbour.h>
+
+#include <asm/system.h>
+#include <asm/irq.h>
+#include <asm/byteorder.h>
+
+/* Maximum number of devices to support. */
+#define PLIP_MAX 8
+
+/* Use 0 for production, 1 for verification, >2 for debug */
+#ifndef NET_DEBUG
+#define NET_DEBUG 1
+#endif
+static const unsigned int net_debug = NET_DEBUG;
+
+#define ENABLE(irq) if (irq != -1) enable_irq(irq)
+#define DISABLE(irq) if (irq != -1) disable_irq(irq)
+
+/* In micro second */
+#define PLIP_DELAY_UNIT 1
+
+/* Connection time out = PLIP_TRIGGER_WAIT * PLIP_DELAY_UNIT usec */
+#define PLIP_TRIGGER_WAIT 500
+
+/* Nibble time out = PLIP_NIBBLE_WAIT * PLIP_DELAY_UNIT usec */
+#define PLIP_NIBBLE_WAIT 3000
+
+/* Bottom halves */
+static void plip_kick_bh(struct work_struct *work);
+static void plip_bh(struct work_struct *work);
+static void plip_timer_bh(struct work_struct *work);
+
+/* Interrupt handler */
+static void plip_interrupt(void *dev_id);
+
+/* Functions for DEV methods */
+static int plip_tx_packet(struct sk_buff *skb, struct net_device *dev);
+static int plip_hard_header(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, const void *daddr,
+ const void *saddr, unsigned len);
+static int plip_hard_header_cache(const struct neighbour *neigh,
+ struct hh_cache *hh, __be16 type);
+static int plip_open(struct net_device *dev);
+static int plip_close(struct net_device *dev);
+static int plip_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
+static int plip_preempt(void *handle);
+static void plip_wakeup(void *handle);
+
+enum plip_connection_state {
+ PLIP_CN_NONE=0,
+ PLIP_CN_RECEIVE,
+ PLIP_CN_SEND,
+ PLIP_CN_CLOSING,
+ PLIP_CN_ERROR
+};
+
+enum plip_packet_state {
+ PLIP_PK_DONE=0,
+ PLIP_PK_TRIGGER,
+ PLIP_PK_LENGTH_LSB,
+ PLIP_PK_LENGTH_MSB,
+ PLIP_PK_DATA,
+ PLIP_PK_CHECKSUM
+};
+
+enum plip_nibble_state {
+ PLIP_NB_BEGIN,
+ PLIP_NB_1,
+ PLIP_NB_2,
+};
+
+struct plip_local {
+ enum plip_packet_state state;
+ enum plip_nibble_state nibble;
+ union {
+ struct {
+#if defined(__LITTLE_ENDIAN)
+ unsigned char lsb;
+ unsigned char msb;
+#elif defined(__BIG_ENDIAN)
+ unsigned char msb;
+ unsigned char lsb;
+#else
+#error "Please fix the endianness defines in <asm/byteorder.h>"
+#endif
+ } b;
+ unsigned short h;
+ } length;
+ unsigned short byte;
+ unsigned char checksum;
+ unsigned char data;
+ struct sk_buff *skb;
+};
+
+struct net_local {
+ struct net_device *dev;
+ struct work_struct immediate;
+ struct delayed_work deferred;
+ struct delayed_work timer;
+ struct plip_local snd_data;
+ struct plip_local rcv_data;
+ struct pardevice *pardev;
+ unsigned long trigger;
+ unsigned long nibble;
+ enum plip_connection_state connection;
+ unsigned short timeout_count;
+ int is_deferred;
+ int port_owner;
+ int should_relinquish;
+ spinlock_t lock;
+ atomic_t kill_timer;
+ struct completion killed_timer_cmp;
+};
+
+static inline void enable_parport_interrupts (struct net_device *dev)
+{
+ if (dev->irq != -1)
+ {
+ struct parport *port =
+ ((struct net_local *)netdev_priv(dev))->pardev->port;
+ port->ops->enable_irq (port);
+ }
+}
+
+static inline void disable_parport_interrupts (struct net_device *dev)
+{
+ if (dev->irq != -1)
+ {
+ struct parport *port =
+ ((struct net_local *)netdev_priv(dev))->pardev->port;
+ port->ops->disable_irq (port);
+ }
+}
+
+static inline void write_data (struct net_device *dev, unsigned char data)
+{
+ struct parport *port =
+ ((struct net_local *)netdev_priv(dev))->pardev->port;
+
+ port->ops->write_data (port, data);
+}
+
+static inline unsigned char read_status (struct net_device *dev)
+{
+ struct parport *port =
+ ((struct net_local *)netdev_priv(dev))->pardev->port;
+
+ return port->ops->read_status (port);
+}
+
+static const struct header_ops plip_header_ops = {
+ .create = plip_hard_header,
+ .cache = plip_hard_header_cache,
+};
+
+static const struct net_device_ops plip_netdev_ops = {
+ .ndo_open = plip_open,
+ .ndo_stop = plip_close,
+ .ndo_start_xmit = plip_tx_packet,
+ .ndo_do_ioctl = plip_ioctl,
+ .ndo_change_mtu = eth_change_mtu,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_validate_addr = eth_validate_addr,
+};
+
+/* Entry point of PLIP driver.
+ Probe the hardware, and register/initialize the driver.
+
+ PLIP is rather weird, because of the way it interacts with the parport
+ system. It is _not_ initialised from Space.c. Instead, plip_init()
+ is called, and that function makes up a "struct net_device" for each port, and
+ then calls us here.
+
+ */
+static void
+plip_init_netdev(struct net_device *dev)
+{
+ struct net_local *nl = netdev_priv(dev);
+
+ /* Then, override parts of it */
+ dev->tx_queue_len = 10;
+ dev->flags = IFF_POINTOPOINT|IFF_NOARP;
+ memset(dev->dev_addr, 0xfc, ETH_ALEN);
+
+ dev->netdev_ops = &plip_netdev_ops;
+ dev->header_ops = &plip_header_ops;
+
+
+ nl->port_owner = 0;
+
+ /* Initialize constants */
+ nl->trigger = PLIP_TRIGGER_WAIT;
+ nl->nibble = PLIP_NIBBLE_WAIT;
+
+ /* Initialize task queue structures */
+ INIT_WORK(&nl->immediate, plip_bh);
+ INIT_DELAYED_WORK(&nl->deferred, plip_kick_bh);
+
+ if (dev->irq == -1)
+ INIT_DELAYED_WORK(&nl->timer, plip_timer_bh);
+
+ spin_lock_init(&nl->lock);
+}
+
+/* Bottom half handler for the delayed request.
+ This routine is kicked by do_timer().
+ Request `plip_bh' to be invoked. */
+static void
+plip_kick_bh(struct work_struct *work)
+{
+ struct net_local *nl =
+ container_of(work, struct net_local, deferred.work);
+
+ if (nl->is_deferred)
+ schedule_work(&nl->immediate);
+}
+
+/* Forward declarations of internal routines */
+static int plip_none(struct net_device *, struct net_local *,
+ struct plip_local *, struct plip_local *);
+static int plip_receive_packet(struct net_device *, struct net_local *,
+ struct plip_local *, struct plip_local *);
+static int plip_send_packet(struct net_device *, struct net_local *,
+ struct plip_local *, struct plip_local *);
+static int plip_connection_close(struct net_device *, struct net_local *,
+ struct plip_local *, struct plip_local *);
+static int plip_error(struct net_device *, struct net_local *,
+ struct plip_local *, struct plip_local *);
+static int plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd,
+ struct plip_local *rcv,
+ int error);
+
+#define OK 0
+#define TIMEOUT 1
+#define ERROR 2
+#define HS_TIMEOUT 3
+
+typedef int (*plip_func)(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd, struct plip_local *rcv);
+
+static const plip_func connection_state_table[] =
+{
+ plip_none,
+ plip_receive_packet,
+ plip_send_packet,
+ plip_connection_close,
+ plip_error
+};
+
+/* Bottom half handler of PLIP. */
+static void
+plip_bh(struct work_struct *work)
+{
+ struct net_local *nl = container_of(work, struct net_local, immediate);
+ struct plip_local *snd = &nl->snd_data;
+ struct plip_local *rcv = &nl->rcv_data;
+ plip_func f;
+ int r;
+
+ nl->is_deferred = 0;
+ f = connection_state_table[nl->connection];
+ if ((r = (*f)(nl->dev, nl, snd, rcv)) != OK &&
+ (r = plip_bh_timeout_error(nl->dev, nl, snd, rcv, r)) != OK) {
+ nl->is_deferred = 1;
+ schedule_delayed_work(&nl->deferred, 1);
+ }
+}
+
+static void
+plip_timer_bh(struct work_struct *work)
+{
+ struct net_local *nl =
+ container_of(work, struct net_local, timer.work);
+
+ if (!(atomic_read (&nl->kill_timer))) {
+ plip_interrupt (nl->dev);
+
+ schedule_delayed_work(&nl->timer, 1);
+ }
+ else {
+ complete(&nl->killed_timer_cmp);
+ }
+}
+
+static int
+plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd, struct plip_local *rcv,
+ int error)
+{
+ unsigned char c0;
+ /*
+ * This is tricky. If we got here from the beginning of send (either
+ * with ERROR or HS_TIMEOUT) we have IRQ enabled. Otherwise it's
+ * already disabled. With the old variant of {enable,disable}_irq()
+ * extra disable_irq() was a no-op. Now it became mortal - it's
+ * unbalanced and thus we'll never re-enable IRQ (until rmmod plip,
+ * that is). So we have to treat HS_TIMEOUT and ERROR from send
+ * in a special way.
+ */
+
+ spin_lock_irq(&nl->lock);
+ if (nl->connection == PLIP_CN_SEND) {
+
+ if (error != ERROR) { /* Timeout */
+ nl->timeout_count++;
+ if ((error == HS_TIMEOUT && nl->timeout_count <= 10) ||
+ nl->timeout_count <= 3) {
+ spin_unlock_irq(&nl->lock);
+ /* Try again later */
+ return TIMEOUT;
+ }
+ c0 = read_status(dev);
+ printk(KERN_WARNING "%s: transmit timeout(%d,%02x)\n",
+ dev->name, snd->state, c0);
+ } else
+ error = HS_TIMEOUT;
+ dev->stats.tx_errors++;
+ dev->stats.tx_aborted_errors++;
+ } else if (nl->connection == PLIP_CN_RECEIVE) {
+ if (rcv->state == PLIP_PK_TRIGGER) {
+ /* Transmission was interrupted. */
+ spin_unlock_irq(&nl->lock);
+ return OK;
+ }
+ if (error != ERROR) { /* Timeout */
+ if (++nl->timeout_count <= 3) {
+ spin_unlock_irq(&nl->lock);
+ /* Try again later */
+ return TIMEOUT;
+ }
+ c0 = read_status(dev);
+ printk(KERN_WARNING "%s: receive timeout(%d,%02x)\n",
+ dev->name, rcv->state, c0);
+ }
+ dev->stats.rx_dropped++;
+ }
+ rcv->state = PLIP_PK_DONE;
+ if (rcv->skb) {
+ kfree_skb(rcv->skb);
+ rcv->skb = NULL;
+ }
+ snd->state = PLIP_PK_DONE;
+ if (snd->skb) {
+ dev_kfree_skb(snd->skb);
+ snd->skb = NULL;
+ }
+ spin_unlock_irq(&nl->lock);
+ if (error == HS_TIMEOUT) {
+ DISABLE(dev->irq);
+ synchronize_irq(dev->irq);
+ }
+ disable_parport_interrupts (dev);
+ netif_stop_queue (dev);
+ nl->connection = PLIP_CN_ERROR;
+ write_data (dev, 0x00);
+
+ return TIMEOUT;
+}
+
+static int
+plip_none(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd, struct plip_local *rcv)
+{
+ return OK;
+}
+
+/* PLIP_RECEIVE --- receive a byte(two nibbles)
+ Returns OK on success, TIMEOUT on timeout */
+static inline int
+plip_receive(unsigned short nibble_timeout, struct net_device *dev,
+ enum plip_nibble_state *ns_p, unsigned char *data_p)
+{
+ unsigned char c0, c1;
+ unsigned int cx;
+
+ switch (*ns_p) {
+ case PLIP_NB_BEGIN:
+ cx = nibble_timeout;
+ while (1) {
+ c0 = read_status(dev);
+ udelay(PLIP_DELAY_UNIT);
+ if ((c0 & 0x80) == 0) {
+ c1 = read_status(dev);
+ if (c0 == c1)
+ break;
+ }
+ if (--cx == 0)
+ return TIMEOUT;
+ }
+ *data_p = (c0 >> 3) & 0x0f;
+ write_data (dev, 0x10); /* send ACK */
+ *ns_p = PLIP_NB_1;
+
+ case PLIP_NB_1:
+ cx = nibble_timeout;
+ while (1) {
+ c0 = read_status(dev);
+ udelay(PLIP_DELAY_UNIT);
+ if (c0 & 0x80) {
+ c1 = read_status(dev);
+ if (c0 == c1)
+ break;
+ }
+ if (--cx == 0)
+ return TIMEOUT;
+ }
+ *data_p |= (c0 << 1) & 0xf0;
+ write_data (dev, 0x00); /* send ACK */
+ *ns_p = PLIP_NB_BEGIN;
+ case PLIP_NB_2:
+ break;
+ }
+ return OK;
+}
+
+/*
+ * Determine the packet's protocol ID. The rule here is that we
+ * assume 802.3 if the type field is short enough to be a length.
+ * This is normal practice and works for any 'now in use' protocol.
+ *
+ * PLIP is ethernet ish but the daddr might not be valid if unicast.
+ * PLIP fortunately has no bus architecture (its Point-to-point).
+ *
+ * We can't fix the daddr thing as that quirk (more bug) is embedded
+ * in far too many old systems not all even running Linux.
+ */
+
+static __be16 plip_type_trans(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ethhdr *eth;
+ unsigned char *rawp;
+
+ skb_reset_mac_header(skb);
+ skb_pull(skb,dev->hard_header_len);
+ eth = eth_hdr(skb);
+
+ if(*eth->h_dest&1)
+ {
+ if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN)==0)
+ skb->pkt_type=PACKET_BROADCAST;
+ else
+ skb->pkt_type=PACKET_MULTICAST;
+ }
+
+ /*
+ * This ALLMULTI check should be redundant by 1.4
+ * so don't forget to remove it.
+ */
+
+ if (ntohs(eth->h_proto) >= 1536)
+ return eth->h_proto;
+
+ rawp = skb->data;
+
+ /*
+ * This is a magic hack to spot IPX packets. Older Novell breaks
+ * the protocol design and runs IPX over 802.3 without an 802.2 LLC
+ * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
+ * won't work for fault tolerant netware but does for the rest.
+ */
+ if (*(unsigned short *)rawp == 0xFFFF)
+ return htons(ETH_P_802_3);
+
+ /*
+ * Real 802.2 LLC
+ */
+ return htons(ETH_P_802_2);
+}
+
+/* PLIP_RECEIVE_PACKET --- receive a packet */
+static int
+plip_receive_packet(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd, struct plip_local *rcv)
+{
+ unsigned short nibble_timeout = nl->nibble;
+ unsigned char *lbuf;
+
+ switch (rcv->state) {
+ case PLIP_PK_TRIGGER:
+ DISABLE(dev->irq);
+ /* Don't need to synchronize irq, as we can safely ignore it */
+ disable_parport_interrupts (dev);
+ write_data (dev, 0x01); /* send ACK */
+ if (net_debug > 2)
+ printk(KERN_DEBUG "%s: receive start\n", dev->name);
+ rcv->state = PLIP_PK_LENGTH_LSB;
+ rcv->nibble = PLIP_NB_BEGIN;
+
+ case PLIP_PK_LENGTH_LSB:
+ if (snd->state != PLIP_PK_DONE) {
+ if (plip_receive(nl->trigger, dev,
+ &rcv->nibble, &rcv->length.b.lsb)) {
+ /* collision, here dev->tbusy == 1 */
+ rcv->state = PLIP_PK_DONE;
+ nl->is_deferred = 1;
+ nl->connection = PLIP_CN_SEND;
+ schedule_delayed_work(&nl->deferred, 1);
+ enable_parport_interrupts (dev);
+ ENABLE(dev->irq);
+ return OK;
+ }
+ } else {
+ if (plip_receive(nibble_timeout, dev,
+ &rcv->nibble, &rcv->length.b.lsb))
+ return TIMEOUT;
+ }
+ rcv->state = PLIP_PK_LENGTH_MSB;
+
+ case PLIP_PK_LENGTH_MSB:
+ if (plip_receive(nibble_timeout, dev,
+ &rcv->nibble, &rcv->length.b.msb))
+ return TIMEOUT;
+ if (rcv->length.h > dev->mtu + dev->hard_header_len ||
+ rcv->length.h < 8) {
+ printk(KERN_WARNING "%s: bogus packet size %d.\n", dev->name, rcv->length.h);
+ return ERROR;
+ }
+ /* Malloc up new buffer. */
+ rcv->skb = dev_alloc_skb(rcv->length.h + 2);
+ if (rcv->skb == NULL) {
+ printk(KERN_ERR "%s: Memory squeeze.\n", dev->name);
+ return ERROR;
+ }
+ skb_reserve(rcv->skb, 2); /* Align IP on 16 byte boundaries */
+ skb_put(rcv->skb,rcv->length.h);
+ rcv->skb->dev = dev;
+ rcv->state = PLIP_PK_DATA;
+ rcv->byte = 0;
+ rcv->checksum = 0;
+
+ case PLIP_PK_DATA:
+ lbuf = rcv->skb->data;
+ do {
+ if (plip_receive(nibble_timeout, dev,
+ &rcv->nibble, &lbuf[rcv->byte]))
+ return TIMEOUT;
+ } while (++rcv->byte < rcv->length.h);
+ do {
+ rcv->checksum += lbuf[--rcv->byte];
+ } while (rcv->byte);
+ rcv->state = PLIP_PK_CHECKSUM;
+
+ case PLIP_PK_CHECKSUM:
+ if (plip_receive(nibble_timeout, dev,
+ &rcv->nibble, &rcv->data))
+ return TIMEOUT;
+ if (rcv->data != rcv->checksum) {
+ dev->stats.rx_crc_errors++;
+ if (net_debug)
+ printk(KERN_DEBUG "%s: checksum error\n", dev->name);
+ return ERROR;
+ }
+ rcv->state = PLIP_PK_DONE;
+
+ case PLIP_PK_DONE:
+ /* Inform the upper layer for the arrival of a packet. */
+ rcv->skb->protocol=plip_type_trans(rcv->skb, dev);
+ netif_rx_ni(rcv->skb);
+ dev->stats.rx_bytes += rcv->length.h;
+ dev->stats.rx_packets++;
+ rcv->skb = NULL;
+ if (net_debug > 2)
+ printk(KERN_DEBUG "%s: receive end\n", dev->name);
+
+ /* Close the connection. */
+ write_data (dev, 0x00);
+ spin_lock_irq(&nl->lock);
+ if (snd->state != PLIP_PK_DONE) {
+ nl->connection = PLIP_CN_SEND;
+ spin_unlock_irq(&nl->lock);
+ schedule_work(&nl->immediate);
+ enable_parport_interrupts (dev);
+ ENABLE(dev->irq);
+ return OK;
+ } else {
+ nl->connection = PLIP_CN_NONE;
+ spin_unlock_irq(&nl->lock);
+ enable_parport_interrupts (dev);
+ ENABLE(dev->irq);
+ return OK;
+ }
+ }
+ return OK;
+}
+
+/* PLIP_SEND --- send a byte (two nibbles)
+ Returns OK on success, TIMEOUT when timeout */
+static inline int
+plip_send(unsigned short nibble_timeout, struct net_device *dev,
+ enum plip_nibble_state *ns_p, unsigned char data)
+{
+ unsigned char c0;
+ unsigned int cx;
+
+ switch (*ns_p) {
+ case PLIP_NB_BEGIN:
+ write_data (dev, data & 0x0f);
+ *ns_p = PLIP_NB_1;
+
+ case PLIP_NB_1:
+ write_data (dev, 0x10 | (data & 0x0f));
+ cx = nibble_timeout;
+ while (1) {
+ c0 = read_status(dev);
+ if ((c0 & 0x80) == 0)
+ break;
+ if (--cx == 0)
+ return TIMEOUT;
+ udelay(PLIP_DELAY_UNIT);
+ }
+ write_data (dev, 0x10 | (data >> 4));
+ *ns_p = PLIP_NB_2;
+
+ case PLIP_NB_2:
+ write_data (dev, (data >> 4));
+ cx = nibble_timeout;
+ while (1) {
+ c0 = read_status(dev);
+ if (c0 & 0x80)
+ break;
+ if (--cx == 0)
+ return TIMEOUT;
+ udelay(PLIP_DELAY_UNIT);
+ }
+ *ns_p = PLIP_NB_BEGIN;
+ return OK;
+ }
+ return OK;
+}
+
+/* PLIP_SEND_PACKET --- send a packet */
+static int
+plip_send_packet(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd, struct plip_local *rcv)
+{
+ unsigned short nibble_timeout = nl->nibble;
+ unsigned char *lbuf;
+ unsigned char c0;
+ unsigned int cx;
+
+ if (snd->skb == NULL || (lbuf = snd->skb->data) == NULL) {
+ printk(KERN_DEBUG "%s: send skb lost\n", dev->name);
+ snd->state = PLIP_PK_DONE;
+ snd->skb = NULL;
+ return ERROR;
+ }
+
+ switch (snd->state) {
+ case PLIP_PK_TRIGGER:
+ if ((read_status(dev) & 0xf8) != 0x80)
+ return HS_TIMEOUT;
+
+ /* Trigger remote rx interrupt. */
+ write_data (dev, 0x08);
+ cx = nl->trigger;
+ while (1) {
+ udelay(PLIP_DELAY_UNIT);
+ spin_lock_irq(&nl->lock);
+ if (nl->connection == PLIP_CN_RECEIVE) {
+ spin_unlock_irq(&nl->lock);
+ /* Interrupted. */
+ dev->stats.collisions++;
+ return OK;
+ }
+ c0 = read_status(dev);
+ if (c0 & 0x08) {
+ spin_unlock_irq(&nl->lock);
+ DISABLE(dev->irq);
+ synchronize_irq(dev->irq);
+ if (nl->connection == PLIP_CN_RECEIVE) {
+ /* Interrupted.
+ We don't need to enable irq,
+ as it is soon disabled. */
+ /* Yes, we do. New variant of
+ {enable,disable}_irq *counts*
+ them. -- AV */
+ ENABLE(dev->irq);
+ dev->stats.collisions++;
+ return OK;
+ }
+ disable_parport_interrupts (dev);
+ if (net_debug > 2)
+ printk(KERN_DEBUG "%s: send start\n", dev->name);
+ snd->state = PLIP_PK_LENGTH_LSB;
+ snd->nibble = PLIP_NB_BEGIN;
+ nl->timeout_count = 0;
+ break;
+ }
+ spin_unlock_irq(&nl->lock);
+ if (--cx == 0) {
+ write_data (dev, 0x00);
+ return HS_TIMEOUT;
+ }
+ }
+
+ case PLIP_PK_LENGTH_LSB:
+ if (plip_send(nibble_timeout, dev,
+ &snd->nibble, snd->length.b.lsb))
+ return TIMEOUT;
+ snd->state = PLIP_PK_LENGTH_MSB;
+
+ case PLIP_PK_LENGTH_MSB:
+ if (plip_send(nibble_timeout, dev,
+ &snd->nibble, snd->length.b.msb))
+ return TIMEOUT;
+ snd->state = PLIP_PK_DATA;
+ snd->byte = 0;
+ snd->checksum = 0;
+
+ case PLIP_PK_DATA:
+ do {
+ if (plip_send(nibble_timeout, dev,
+ &snd->nibble, lbuf[snd->byte]))
+ return TIMEOUT;
+ } while (++snd->byte < snd->length.h);
+ do {
+ snd->checksum += lbuf[--snd->byte];
+ } while (snd->byte);
+ snd->state = PLIP_PK_CHECKSUM;
+
+ case PLIP_PK_CHECKSUM:
+ if (plip_send(nibble_timeout, dev,
+ &snd->nibble, snd->checksum))
+ return TIMEOUT;
+
+ dev->stats.tx_bytes += snd->skb->len;
+ dev_kfree_skb(snd->skb);
+ dev->stats.tx_packets++;
+ snd->state = PLIP_PK_DONE;
+
+ case PLIP_PK_DONE:
+ /* Close the connection */
+ write_data (dev, 0x00);
+ snd->skb = NULL;
+ if (net_debug > 2)
+ printk(KERN_DEBUG "%s: send end\n", dev->name);
+ nl->connection = PLIP_CN_CLOSING;
+ nl->is_deferred = 1;
+ schedule_delayed_work(&nl->deferred, 1);
+ enable_parport_interrupts (dev);
+ ENABLE(dev->irq);
+ return OK;
+ }
+ return OK;
+}
+
+static int
+plip_connection_close(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd, struct plip_local *rcv)
+{
+ spin_lock_irq(&nl->lock);
+ if (nl->connection == PLIP_CN_CLOSING) {
+ nl->connection = PLIP_CN_NONE;
+ netif_wake_queue (dev);
+ }
+ spin_unlock_irq(&nl->lock);
+ if (nl->should_relinquish) {
+ nl->should_relinquish = nl->port_owner = 0;
+ parport_release(nl->pardev);
+ }
+ return OK;
+}
+
+/* PLIP_ERROR --- wait till other end settled */
+static int
+plip_error(struct net_device *dev, struct net_local *nl,
+ struct plip_local *snd, struct plip_local *rcv)
+{
+ unsigned char status;
+
+ status = read_status(dev);
+ if ((status & 0xf8) == 0x80) {
+ if (net_debug > 2)
+ printk(KERN_DEBUG "%s: reset interface.\n", dev->name);
+ nl->connection = PLIP_CN_NONE;
+ nl->should_relinquish = 0;
+ netif_start_queue (dev);
+ enable_parport_interrupts (dev);
+ ENABLE(dev->irq);
+ netif_wake_queue (dev);
+ } else {
+ nl->is_deferred = 1;
+ schedule_delayed_work(&nl->deferred, 1);
+ }
+
+ return OK;
+}
+
+/* Handle the parallel port interrupts. */
+static void
+plip_interrupt(void *dev_id)
+{
+ struct net_device *dev = dev_id;
+ struct net_local *nl;
+ struct plip_local *rcv;
+ unsigned char c0;
+ unsigned long flags;
+
+ nl = netdev_priv(dev);
+ rcv = &nl->rcv_data;
+
+ spin_lock_irqsave (&nl->lock, flags);
+
+ c0 = read_status(dev);
+ if ((c0 & 0xf8) != 0xc0) {
+ if ((dev->irq != -1) && (net_debug > 1))
+ printk(KERN_DEBUG "%s: spurious interrupt\n", dev->name);
+ spin_unlock_irqrestore (&nl->lock, flags);
+ return;
+ }
+
+ if (net_debug > 3)
+ printk(KERN_DEBUG "%s: interrupt.\n", dev->name);
+
+ switch (nl->connection) {
+ case PLIP_CN_CLOSING:
+ netif_wake_queue (dev);
+ case PLIP_CN_NONE:
+ case PLIP_CN_SEND:
+ rcv->state = PLIP_PK_TRIGGER;
+ nl->connection = PLIP_CN_RECEIVE;
+ nl->timeout_count = 0;
+ schedule_work(&nl->immediate);
+ break;
+
+ case PLIP_CN_RECEIVE:
+ /* May occur because there is race condition
+ around test and set of dev->interrupt.
+ Ignore this interrupt. */
+ break;
+
+ case PLIP_CN_ERROR:
+ printk(KERN_ERR "%s: receive interrupt in error state\n", dev->name);
+ break;
+ }
+
+ spin_unlock_irqrestore(&nl->lock, flags);
+}
+
+static int
+plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
+{
+ struct net_local *nl = netdev_priv(dev);
+ struct plip_local *snd = &nl->snd_data;
+
+ if (netif_queue_stopped(dev))
+ return NETDEV_TX_BUSY;
+
+ /* We may need to grab the bus */
+ if (!nl->port_owner) {
+ if (parport_claim(nl->pardev))
+ return NETDEV_TX_BUSY;
+ nl->port_owner = 1;
+ }
+
+ netif_stop_queue (dev);
+
+ if (skb->len > dev->mtu + dev->hard_header_len) {
+ printk(KERN_WARNING "%s: packet too big, %d.\n", dev->name, (int)skb->len);
+ netif_start_queue (dev);
+ return NETDEV_TX_BUSY;
+ }
+
+ if (net_debug > 2)
+ printk(KERN_DEBUG "%s: send request\n", dev->name);
+
+ spin_lock_irq(&nl->lock);
+ snd->skb = skb;
+ snd->length.h = skb->len;
+ snd->state = PLIP_PK_TRIGGER;
+ if (nl->connection == PLIP_CN_NONE) {
+ nl->connection = PLIP_CN_SEND;
+ nl->timeout_count = 0;
+ }
+ schedule_work(&nl->immediate);
+ spin_unlock_irq(&nl->lock);
+
+ return NETDEV_TX_OK;
+}
+
+static void
+plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
+{
+ const struct in_device *in_dev;
+
+ rcu_read_lock();
+ in_dev = __in_dev_get_rcu(dev);
+ if (in_dev) {
+ /* Any address will do - we take the first */
+ const struct in_ifaddr *ifa = in_dev->ifa_list;
+ if (ifa) {
+ memcpy(eth->h_source, dev->dev_addr, 6);
+ memset(eth->h_dest, 0xfc, 2);
+ memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
+ }
+ }
+ rcu_read_unlock();
+}
+
+static int
+plip_hard_header(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, const void *daddr,
+ const void *saddr, unsigned len)
+{
+ int ret;
+
+ ret = eth_header(skb, dev, type, daddr, saddr, len);
+ if (ret >= 0)
+ plip_rewrite_address (dev, (struct ethhdr *)skb->data);
+
+ return ret;
+}
+
+static int plip_hard_header_cache(const struct neighbour *neigh,
+ struct hh_cache *hh, __be16 type)
+{
+ int ret;
+
+ ret = eth_header_cache(neigh, hh, type);
+ if (ret == 0) {
+ struct ethhdr *eth;
+
+ eth = (struct ethhdr*)(((u8*)hh->hh_data) +
+ HH_DATA_OFF(sizeof(*eth)));
+ plip_rewrite_address (neigh->dev, eth);
+ }
+
+ return ret;
+}
+
+/* Open/initialize the board. This is called (in the current kernel)
+ sometime after booting when the 'ifconfig' program is run.
+
+ This routine gets exclusive access to the parallel port by allocating
+ its IRQ line.
+ */
+static int
+plip_open(struct net_device *dev)
+{
+ struct net_local *nl = netdev_priv(dev);
+ struct in_device *in_dev;
+
+ /* Grab the port */
+ if (!nl->port_owner) {
+ if (parport_claim(nl->pardev)) return -EAGAIN;
+ nl->port_owner = 1;
+ }
+
+ nl->should_relinquish = 0;
+
+ /* Clear the data port. */
+ write_data (dev, 0x00);
+
+ /* Enable rx interrupt. */
+ enable_parport_interrupts (dev);
+ if (dev->irq == -1)
+ {
+ atomic_set (&nl->kill_timer, 0);
+ schedule_delayed_work(&nl->timer, 1);
+ }
+
+ /* Initialize the state machine. */
+ nl->rcv_data.state = nl->snd_data.state = PLIP_PK_DONE;
+ nl->rcv_data.skb = nl->snd_data.skb = NULL;
+ nl->connection = PLIP_CN_NONE;
+ nl->is_deferred = 0;
+
+ /* Fill in the MAC-level header.
+ We used to abuse dev->broadcast to store the point-to-point
+ MAC address, but we no longer do it. Instead, we fetch the
+ interface address whenever it is needed, which is cheap enough
+ because we use the hh_cache. Actually, abusing dev->broadcast
+ didn't work, because when using plip_open the point-to-point
+ address isn't yet known.
+ PLIP doesn't have a real MAC address, but we need it to be
+ DOS compatible, and to properly support taps (otherwise,
+ when the device address isn't identical to the address of a
+ received frame, the kernel incorrectly drops it). */
+
+ in_dev=__in_dev_get_rtnl(dev);
+ if (in_dev) {
+ /* Any address will do - we take the first. We already
+ have the first two bytes filled with 0xfc, from
+ plip_init_dev(). */
+ struct in_ifaddr *ifa=in_dev->ifa_list;
+ if (ifa != NULL) {
+ memcpy(dev->dev_addr+2, &ifa->ifa_local, 4);
+ }
+ }
+
+ netif_start_queue (dev);
+
+ return 0;
+}
+
+/* The inverse routine to plip_open (). */
+static int
+plip_close(struct net_device *dev)
+{
+ struct net_local *nl = netdev_priv(dev);
+ struct plip_local *snd = &nl->snd_data;
+ struct plip_local *rcv = &nl->rcv_data;
+
+ netif_stop_queue (dev);
+ DISABLE(dev->irq);
+ synchronize_irq(dev->irq);
+
+ if (dev->irq == -1)
+ {
+ init_completion(&nl->killed_timer_cmp);
+ atomic_set (&nl->kill_timer, 1);
+ wait_for_completion(&nl->killed_timer_cmp);
+ }
+
+#ifdef NOTDEF
+ outb(0x00, PAR_DATA(dev));
+#endif
+ nl->is_deferred = 0;
+ nl->connection = PLIP_CN_NONE;
+ if (nl->port_owner) {
+ parport_release(nl->pardev);
+ nl->port_owner = 0;
+ }
+
+ snd->state = PLIP_PK_DONE;
+ if (snd->skb) {
+ dev_kfree_skb(snd->skb);
+ snd->skb = NULL;
+ }
+ rcv->state = PLIP_PK_DONE;
+ if (rcv->skb) {
+ kfree_skb(rcv->skb);
+ rcv->skb = NULL;
+ }
+
+#ifdef NOTDEF
+ /* Reset. */
+ outb(0x00, PAR_CONTROL(dev));
+#endif
+ return 0;
+}
+
+static int
+plip_preempt(void *handle)
+{
+ struct net_device *dev = (struct net_device *)handle;
+ struct net_local *nl = netdev_priv(dev);
+
+ /* Stand our ground if a datagram is on the wire */
+ if (nl->connection != PLIP_CN_NONE) {
+ nl->should_relinquish = 1;
+ return 1;
+ }
+
+ nl->port_owner = 0; /* Remember that we released the bus */
+ return 0;
+}
+
+static void
+plip_wakeup(void *handle)
+{
+ struct net_device *dev = (struct net_device *)handle;
+ struct net_local *nl = netdev_priv(dev);
+
+ if (nl->port_owner) {
+ /* Why are we being woken up? */
+ printk(KERN_DEBUG "%s: why am I being woken up?\n", dev->name);
+ if (!parport_claim(nl->pardev))
+ /* bus_owner is already set (but why?) */
+ printk(KERN_DEBUG "%s: I'm broken.\n", dev->name);
+ else
+ return;
+ }
+
+ if (!(dev->flags & IFF_UP))
+ /* Don't need the port when the interface is down */
+ return;
+
+ if (!parport_claim(nl->pardev)) {
+ nl->port_owner = 1;
+ /* Clear the data port. */
+ write_data (dev, 0x00);
+ }
+}
+
+static int
+plip_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+ struct net_local *nl = netdev_priv(dev);
+ struct plipconf *pc = (struct plipconf *) &rq->ifr_ifru;
+
+ if (cmd != SIOCDEVPLIP)
+ return -EOPNOTSUPP;
+
+ switch(pc->pcmd) {
+ case PLIP_GET_TIMEOUT:
+ pc->trigger = nl->trigger;
+ pc->nibble = nl->nibble;
+ break;
+ case PLIP_SET_TIMEOUT:
+ if(!capable(CAP_NET_ADMIN))
+ return -EPERM;
+ nl->trigger = pc->trigger;
+ nl->nibble = pc->nibble;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+ return 0;
+}
+
+static int parport[PLIP_MAX] = { [0 ... PLIP_MAX-1] = -1 };
+static int timid;
+
+module_param_array(parport, int, NULL, 0);
+module_param(timid, int, 0);
+MODULE_PARM_DESC(parport, "List of parport device numbers to use by plip");
+
+static struct net_device *dev_plip[PLIP_MAX] = { NULL, };
+
+static inline int
+plip_searchfor(int list[], int a)
+{
+ int i;
+ for (i = 0; i < PLIP_MAX && list[i] != -1; i++) {
+ if (list[i] == a) return 1;
+ }
+ return 0;
+}
+
+/* plip_attach() is called (by the parport code) when a port is
+ * available to use. */
+static void plip_attach (struct parport *port)
+{
+ static int unit;
+ struct net_device *dev;
+ struct net_local *nl;
+ char name[IFNAMSIZ];
+
+ if ((parport[0] == -1 && (!timid || !port->devices)) ||
+ plip_searchfor(parport, port->number)) {
+ if (unit == PLIP_MAX) {
+ printk(KERN_ERR "plip: too many devices\n");
+ return;
+ }
+
+ sprintf(name, "plip%d", unit);
+ dev = alloc_etherdev(sizeof(struct net_local));
+ if (!dev) {
+ printk(KERN_ERR "plip: memory squeeze\n");
+ return;
+ }
+
+ strcpy(dev->name, name);
+
+ dev->irq = port->irq;
+ dev->base_addr = port->base;
+ if (port->irq == -1) {
+ printk(KERN_INFO "plip: %s has no IRQ. Using IRQ-less mode,"
+ "which is fairly inefficient!\n", port->name);
+ }
+
+ nl = netdev_priv(dev);
+ nl->dev = dev;
+ nl->pardev = parport_register_device(port, dev->name, plip_preempt,
+ plip_wakeup, plip_interrupt,
+ 0, dev);
+
+ if (!nl->pardev) {
+ printk(KERN_ERR "%s: parport_register failed\n", name);
+ goto err_free_dev;
+ }
+
+ plip_init_netdev(dev);
+
+ if (register_netdev(dev)) {
+ printk(KERN_ERR "%s: network register failed\n", name);
+ goto err_parport_unregister;
+ }
+
+ printk(KERN_INFO "%s", version);
+ if (dev->irq != -1)
+ printk(KERN_INFO "%s: Parallel port at %#3lx, "
+ "using IRQ %d.\n",
+ dev->name, dev->base_addr, dev->irq);
+ else
+ printk(KERN_INFO "%s: Parallel port at %#3lx, "
+ "not using IRQ.\n",
+ dev->name, dev->base_addr);
+ dev_plip[unit++] = dev;
+ }
+ return;
+
+err_parport_unregister:
+ parport_unregister_device(nl->pardev);
+err_free_dev:
+ free_netdev(dev);
+}
+
+/* plip_detach() is called (by the parport code) when a port is
+ * no longer available to use. */
+static void plip_detach (struct parport *port)
+{
+ /* Nothing to do */
+}
+
+static struct parport_driver plip_driver = {
+ .name = "plip",
+ .attach = plip_attach,
+ .detach = plip_detach
+};
+
+static void __exit plip_cleanup_module (void)
+{
+ struct net_device *dev;
+ int i;
+
+ parport_unregister_driver (&plip_driver);
+
+ for (i=0; i < PLIP_MAX; i++) {
+ if ((dev = dev_plip[i])) {
+ struct net_local *nl = netdev_priv(dev);
+ unregister_netdev(dev);
+ if (nl->port_owner)
+ parport_release(nl->pardev);
+ parport_unregister_device(nl->pardev);
+ free_netdev(dev);
+ dev_plip[i] = NULL;
+ }
+ }
+}
+
+#ifndef MODULE
+
+static int parport_ptr;
+
+static int __init plip_setup(char *str)
+{
+ int ints[4];
+
+ str = get_options(str, ARRAY_SIZE(ints), ints);
+
+ /* Ugh. */
+ if (!strncmp(str, "parport", 7)) {
+ int n = simple_strtoul(str+7, NULL, 10);
+ if (parport_ptr < PLIP_MAX)
+ parport[parport_ptr++] = n;
+ else
+ printk(KERN_INFO "plip: too many ports, %s ignored.\n",
+ str);
+ } else if (!strcmp(str, "timid")) {
+ timid = 1;
+ } else {
+ if (ints[0] == 0 || ints[1] == 0) {
+ /* disable driver on "plip=" or "plip=0" */
+ parport[0] = -2;
+ } else {
+ printk(KERN_WARNING "warning: 'plip=0x%x' ignored\n",
+ ints[1]);
+ }
+ }
+ return 1;
+}
+
+__setup("plip=", plip_setup);
+
+#endif /* !MODULE */
+
+static int __init plip_init (void)
+{
+ if (parport[0] == -2)
+ return 0;
+
+ if (parport[0] != -1 && timid) {
+ printk(KERN_WARNING "plip: warning, ignoring `timid' since specific ports given.\n");
+ timid = 0;
+ }
+
+ if (parport_register_driver (&plip_driver)) {
+ printk (KERN_WARNING "plip: couldn't register driver\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+module_init(plip_init);
+module_exit(plip_cleanup_module);
+MODULE_LICENSE("GPL");