| /* $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/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/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 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(int irq, 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, 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 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; |
| 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; |
| }; |
| |
| static inline 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); |
| } |
| } |
| |
| static inline 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); |
| } |
| } |
| |
| static inline 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); |
| } |
| |
| static inline 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->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, 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 (-1, nl->dev); |
| |
| 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; |
| 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(rcv->skb); |
| dev->last_rx = jiffies; |
| 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(int irq, void *dev_id) |
| { |
| struct net_device *dev = dev_id; |
| struct net_local *nl; |
| struct plip_local *rcv; |
| unsigned char c0; |
| |
| 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 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, 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: |
| */ |