plip.c
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- /* $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.jpn";
- /*
- 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/sched.h>
- #include <linux/types.h>
- #include <linux/fcntl.h>
- #include <linux/interrupt.h>
- #include <linux/string.h>
- #include <linux/ptrace.h>
- #include <linux/if_ether.h>
- #include <asm/system.h>
- #include <linux/in.h>
- #include <linux/errno.h>
- #include <linux/delay.h>
- #include <linux/lp.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 <net/neighbour.h>
- #include <linux/tqueue.h>
- #include <linux/ioport.h>
- #include <linux/spinlock.h>
- #include <asm/bitops.h>
- #include <asm/irq.h>
- #include <asm/byteorder.h>
- #include <asm/semaphore.h>
- #include <linux/parport.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 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 net_device *dev);
- static void plip_bh(struct net_device *dev);
- static void plip_timer_bh(struct net_device *dev);
- /* Interrupt handler */
- static void plip_interrupt(int irq, void *dev_id, struct pt_regs *regs);
- /* 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, void *daddr,
- void *saddr, unsigned len);
- static int plip_hard_header_cache(struct neighbour *neigh,
- struct hh_cache *hh);
- static int plip_open(struct net_device *dev);
- static int plip_close(struct net_device *dev);
- static struct net_device_stats *plip_get_stats(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_stats enet_stats;
- struct tq_struct immediate;
- struct tq_struct deferred;
- struct tq_struct 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;
- int (*orig_hard_header)(struct sk_buff *skb, struct net_device *dev,
- unsigned short type, void *daddr,
- void *saddr, unsigned len);
- int (*orig_hard_header_cache)(struct neighbour *neigh,
- struct hh_cache *hh);
- spinlock_t lock;
- atomic_t kill_timer;
- struct semaphore killed_timer_sem;
- };
- inline static void enable_parport_interrupts (struct net_device *dev)
- {
- if (dev->irq != -1)
- {
- struct parport *port =
- ((struct net_local *)dev->priv)->pardev->port;
- port->ops->enable_irq (port);
- }
- }
- inline static void disable_parport_interrupts (struct net_device *dev)
- {
- if (dev->irq != -1)
- {
- struct parport *port =
- ((struct net_local *)dev->priv)->pardev->port;
- port->ops->disable_irq (port);
- }
- }
- inline static void write_data (struct net_device *dev, unsigned char data)
- {
- struct parport *port =
- ((struct net_local *)dev->priv)->pardev->port;
- port->ops->write_data (port, data);
- }
- inline static unsigned char read_status (struct net_device *dev)
- {
- struct parport *port =
- ((struct net_local *)dev->priv)->pardev->port;
- return port->ops->read_status (port);
- }
- /* 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.
- */
- int __init
- plip_init_dev(struct net_device *dev, struct parport *pb)
- {
- struct net_local *nl;
- struct pardevice *pardev;
- SET_MODULE_OWNER(dev);
- dev->irq = pb->irq;
- dev->base_addr = pb->base;
- if (pb->irq == -1) {
- printk(KERN_INFO "plip: %s has no IRQ. Using IRQ-less mode,"
- "which is fairly inefficient!n", pb->name);
- }
- pardev = parport_register_device(pb, dev->name, plip_preempt,
- plip_wakeup, plip_interrupt,
- 0, dev);
- if (!pardev)
- return -ENODEV;
- 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);
- /* Fill in the generic fields of the device structure. */
- ether_setup(dev);
- /* Then, override parts of it */
- dev->hard_start_xmit = plip_tx_packet;
- dev->open = plip_open;
- dev->stop = plip_close;
- dev->get_stats = plip_get_stats;
- dev->do_ioctl = plip_ioctl;
- dev->header_cache_update = NULL;
- dev->tx_queue_len = 10;
- dev->flags = IFF_POINTOPOINT|IFF_NOARP;
- memset(dev->dev_addr, 0xfc, ETH_ALEN);
- /* Set the private structure */
- dev->priv = kmalloc(sizeof (struct net_local), GFP_KERNEL);
- if (dev->priv == NULL) {
- printk(KERN_ERR "%s: out of memoryn", dev->name);
- parport_unregister_device(pardev);
- return -ENOMEM;
- }
- memset(dev->priv, 0, sizeof(struct net_local));
- nl = (struct net_local *) dev->priv;
- nl->orig_hard_header = dev->hard_header;
- dev->hard_header = plip_hard_header;
- nl->orig_hard_header_cache = dev->hard_header_cache;
- dev->hard_header_cache = plip_hard_header_cache;
- nl->pardev = pardev;
- nl->port_owner = 0;
- /* Initialize constants */
- nl->trigger = PLIP_TRIGGER_WAIT;
- nl->nibble = PLIP_NIBBLE_WAIT;
- /* Initialize task queue structures */
- INIT_LIST_HEAD(&nl->immediate.list);
- nl->immediate.sync = 0;
- nl->immediate.routine = (void (*)(void *))plip_bh;
- nl->immediate.data = dev;
- INIT_LIST_HEAD(&nl->deferred.list);
- nl->deferred.sync = 0;
- nl->deferred.routine = (void (*)(void *))plip_kick_bh;
- nl->deferred.data = dev;
- if (dev->irq == -1) {
- INIT_LIST_HEAD(&nl->timer.list);
- nl->timer.sync = 0;
- nl->timer.routine = (void (*)(void *))plip_timer_bh;
- nl->timer.data = dev;
- }
- spin_lock_init(&nl->lock);
- return 0;
- }
- /* 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 net_device *dev)
- {
- struct net_local *nl = (struct net_local *)dev->priv;
- if (nl->is_deferred) {
- queue_task(&nl->immediate, &tq_immediate);
- mark_bh(IMMEDIATE_BH);
- }
- }
- /* 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 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 net_device *dev)
- {
- struct net_local *nl = (struct net_local *)dev->priv;
- 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)(dev, nl, snd, rcv)) != OK
- && (r = plip_bh_timeout_error(dev, nl, snd, rcv, r)) != OK) {
- nl->is_deferred = 1;
- queue_task(&nl->deferred, &tq_timer);
- }
- }
- static void
- plip_timer_bh(struct net_device *dev)
- {
- struct net_local *nl = (struct net_local *)dev->priv;
-
- if (!(atomic_read (&nl->kill_timer))) {
- plip_interrupt (-1, dev, NULL);
- queue_task (&nl->timer, &tq_timer);
- }
- else {
- up (&nl->killed_timer_sem);
- }
- }
- 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;
- nl->enet_stats.tx_errors++;
- nl->enet_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);
- }
- nl->enet_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();
- }
- 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 */
- inline static 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 unsigned short plip_type_trans(struct sk_buff *skb, struct net_device *dev)
- {
- struct ethhdr *eth;
- unsigned char *rawp;
-
- skb->mac.raw=skb->data;
- skb_pull(skb,dev->hard_header_len);
- eth= skb->mac.ethernet;
-
- 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 startn", 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;
- queue_task(&nl->deferred, &tq_timer);
- 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) {
- nl->enet_stats.rx_crc_errors++;
- if (net_debug)
- printk(KERN_DEBUG "%s: checksum errorn", 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(rcv->skb);
- dev->last_rx = jiffies;
- nl->enet_stats.rx_bytes += rcv->length.h;
- nl->enet_stats.rx_packets++;
- rcv->skb = NULL;
- if (net_debug > 2)
- printk(KERN_DEBUG "%s: receive endn", 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);
- queue_task(&nl->immediate, &tq_immediate);
- mark_bh(IMMEDIATE_BH);
- 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 */
- inline static 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 lostn", 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. */
- nl->enet_stats.collisions++;
- return OK;
- }
- c0 = read_status(dev);
- if (c0 & 0x08) {
- spin_unlock_irq(&nl->lock);
- DISABLE(dev->irq);
- synchronize_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);
- nl->enet_stats.collisions++;
- return OK;
- }
- disable_parport_interrupts (dev);
- if (net_debug > 2)
- printk(KERN_DEBUG "%s: send startn", 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;
- nl->enet_stats.tx_bytes += snd->skb->len;
- dev_kfree_skb(snd->skb);
- nl->enet_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 endn", dev->name);
- nl->connection = PLIP_CN_CLOSING;
- nl->is_deferred = 1;
- queue_task(&nl->deferred, &tq_timer);
- 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;
- queue_task(&nl->deferred, &tq_timer);
- }
- return OK;
- }
- /* Handle the parallel port interrupts. */
- static void
- plip_interrupt(int irq, void *dev_id, struct pt_regs * regs)
- {
- struct net_device *dev = dev_id;
- struct net_local *nl;
- struct plip_local *rcv;
- unsigned char c0;
- if (dev == NULL) {
- printk(KERN_DEBUG "plip_interrupt: irq %d for unknown device.n", irq);
- return;
- }
- nl = (struct net_local *)dev->priv;
- rcv = &nl->rcv_data;
- spin_lock_irq (&nl->lock);
- c0 = read_status(dev);
- if ((c0 & 0xf8) != 0xc0) {
- if ((dev->irq != -1) && (net_debug > 1))
- printk(KERN_DEBUG "%s: spurious interruptn", dev->name);
- spin_unlock_irq (&nl->lock);
- 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;
- queue_task(&nl->immediate, &tq_immediate);
- mark_bh(IMMEDIATE_BH);
- 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 staten", dev->name);
- break;
- }
- spin_unlock_irq(&nl->lock);
- }
- static int
- plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
- {
- struct net_local *nl = (struct net_local *)dev->priv;
- struct plip_local *snd = &nl->snd_data;
- if (netif_queue_stopped(dev))
- return 1;
- /* We may need to grab the bus */
- if (!nl->port_owner) {
- if (parport_claim(nl->pardev))
- return 1;
- 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 1;
- }
- if (net_debug > 2)
- printk(KERN_DEBUG "%s: send requestn", dev->name);
- spin_lock_irq(&nl->lock);
- dev->trans_start = jiffies;
- 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;
- }
- queue_task(&nl->immediate, &tq_immediate);
- mark_bh(IMMEDIATE_BH);
- spin_unlock_irq(&nl->lock);
-
- return 0;
- }
- static void
- plip_rewrite_address(struct net_device *dev, struct ethhdr *eth)
- {
- struct in_device *in_dev;
- if ((in_dev=dev->ip_ptr) != NULL) {
- /* Any address will do - we take the first */
- struct in_ifaddr *ifa=in_dev->ifa_list;
- if (ifa != NULL) {
- memcpy(eth->h_source, dev->dev_addr, 6);
- memset(eth->h_dest, 0xfc, 2);
- memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
- }
- }
- }
- static int
- plip_hard_header(struct sk_buff *skb, struct net_device *dev,
- unsigned short type, void *daddr,
- void *saddr, unsigned len)
- {
- struct net_local *nl = (struct net_local *)dev->priv;
- int ret;
- if ((ret = nl->orig_hard_header(skb, dev, type, daddr, saddr, len)) >= 0)
- plip_rewrite_address (dev, (struct ethhdr *)skb->data);
- return ret;
- }
- int plip_hard_header_cache(struct neighbour *neigh,
- struct hh_cache *hh)
- {
- struct net_local *nl = (struct net_local *)neigh->dev->priv;
- int ret;
-
- if ((ret = nl->orig_hard_header_cache(neigh, hh)) == 0)
- {
- struct ethhdr *eth = (struct ethhdr*)(((u8*)hh->hh_data) + 2);
- 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 = (struct net_local *)dev->priv;
- 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);
- queue_task (&nl->timer, &tq_timer);
- }
- /* 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). */
- if ((in_dev=dev->ip_ptr) != NULL) {
- /* 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 = (struct net_local *)dev->priv;
- struct plip_local *snd = &nl->snd_data;
- struct plip_local *rcv = &nl->rcv_data;
- netif_stop_queue (dev);
- DISABLE(dev->irq);
- synchronize_irq();
- if (dev->irq == -1)
- {
- init_MUTEX_LOCKED (&nl->killed_timer_sem);
- atomic_set (&nl->kill_timer, 1);
- down (&nl->killed_timer_sem);
- }
- #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 = (struct net_local *)dev->priv;
- /* 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 = (struct net_local *)dev->priv;
- 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);
- }
- return;
- }
- static struct net_device_stats *
- plip_get_stats(struct net_device *dev)
- {
- struct net_local *nl = (struct net_local *)dev->priv;
- struct net_device_stats *r = &nl->enet_stats;
- return r;
- }
- static int
- plip_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
- {
- struct net_local *nl = (struct net_local *) dev->priv;
- struct plipconf *pc = (struct plipconf *) &rq->ifr_data;
- 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_PARM(parport, "1-" __MODULE_STRING(PLIP_MAX) "i");
- MODULE_PARM(timid, "1i");
- MODULE_PARM_DESC(parport, "List of parport device numbers to use by plip");
- static struct net_device *dev_plip[PLIP_MAX] = { NULL, };
- static int inline
- 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 i;
- if ((parport[0] == -1 && (!timid || !port->devices)) ||
- plip_searchfor(parport, port->number)) {
- if (i == PLIP_MAX) {
- printk(KERN_ERR "plip: too many devicesn");
- return;
- }
- dev_plip[i] = kmalloc(sizeof(struct net_device),
- GFP_KERNEL);
- if (!dev_plip[i]) {
- printk(KERN_ERR "plip: memory squeezen");
- return;
- }
- memset(dev_plip[i], 0, sizeof(struct net_device));
- sprintf(dev_plip[i]->name, "plip%d", i);
- dev_plip[i]->priv = port;
- if (plip_init_dev(dev_plip[i],port) ||
- register_netdev(dev_plip[i])) {
- kfree(dev_plip[i]);
- dev_plip[i] = NULL;
- } else {
- i++;
- }
- }
- }
- /* 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)
- {
- int i;
- parport_unregister_driver (&plip_driver);
- for (i=0; i < PLIP_MAX; i++) {
- if (dev_plip[i]) {
- struct net_local *nl =
- (struct net_local *)dev_plip[i]->priv;
- unregister_netdev(dev_plip[i]);
- if (nl->port_owner)
- parport_release(nl->pardev);
- parport_unregister_device(nl->pardev);
- kfree(dev_plip[i]->priv);
- kfree(dev_plip[i]);
- 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' ignoredn",
- 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 drivern");
- return 1;
- }
- return 0;
- }
- module_init(plip_init);
- module_exit(plip_cleanup_module);
- MODULE_LICENSE("GPL");
- /*
- * Local variables:
- * compile-command: "gcc -DMODULE -DMODVERSIONS -D__KERNEL__ -Wall -Wstrict-prototypes -O2 -g -fomit-frame-pointer -pipe -c plip.c"
- * End:
- */