diff options
Diffstat (limited to 'drivers/net/plip.c')
| -rw-r--r-- | drivers/net/plip.c | 1427 |
1 files changed, 1427 insertions, 0 deletions
diff --git a/drivers/net/plip.c b/drivers/net/plip.c new file mode 100644 index 00000000000..f4b62405d2e --- /dev/null +++ b/drivers/net/plip.c @@ -0,0 +1,1427 @@ +/* $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/if_ether.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 <linux/workqueue.h> +#include <linux/ioport.h> +#include <linux/spinlock.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> +#include <asm/semaphore.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 work_struct immediate; + struct work_struct deferred; + struct work_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. + + */ +static void +plip_init_netdev(struct net_device *dev) +{ + struct net_local *nl = netdev_priv(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 */ + 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->port_owner = 0; + + /* Initialize constants */ + nl->trigger = PLIP_TRIGGER_WAIT; + nl->nibble = PLIP_NIBBLE_WAIT; + + /* Initialize task queue structures */ + INIT_WORK(&nl->immediate, (void (*)(void *))plip_bh, dev); + INIT_WORK(&nl->deferred, (void (*)(void *))plip_kick_bh, dev); + + if (dev->irq == -1) + INIT_WORK(&nl->timer, (void (*)(void *))plip_timer_bh, dev); + + 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 net_device *dev) +{ + struct net_local *nl = netdev_priv(dev); + + 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 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 = netdev_priv(dev); + 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; + schedule_delayed_work(&nl->deferred, 1); + } +} + +static void +plip_timer_bh(struct net_device *dev) +{ + struct net_local *nl = netdev_priv(dev); + + if (!(atomic_read (&nl->kill_timer))) { + plip_interrupt (-1, dev, NULL); + + schedule_delayed_work(&nl->timer, 1); + } + 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(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 */ +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 = 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) { + nl->enet_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(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 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 */ +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 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. */ + nl->enet_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); + nl->enet_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; + + 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 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(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 = netdev_priv(dev); + 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 interrupt\n", 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; + 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_irq(&nl->lock); +} + +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 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 request\n", 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; + } + schedule_work(&nl->immediate); + 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 = netdev_priv(dev); + 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 = neigh->dev->priv; + int ret; + + if ((ret = nl->orig_hard_header_cache(neigh, hh)) == 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). */ + + 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 = 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_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 = 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); + } + + return; +} + +static struct net_device_stats * +plip_get_stats(struct net_device *dev) +{ + struct net_local *nl = netdev_priv(dev); + 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 = 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); + + SET_MODULE_OWNER(dev); + 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->pardev = parport_register_device(port, 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; + return; + } + + 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); + return; +} + +/* 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"); + +/* + * Local variables: + * compile-command: "gcc -DMODULE -DMODVERSIONS -D__KERNEL__ -Wall -Wstrict-prototypes -O2 -g -fomit-frame-pointer -pipe -c plip.c" + * End: + */ |