dt-bindings: mtd: ingenic: Use standard ecc-engine property
[linux/fpc-iii.git] / drivers / net / plip / plip.c
blobfeb92ecd18803ae1762aa232faa11783f18461d2
1 /* $Id: plip.c,v 1.3.6.2 1997/04/16 15:07:56 phil Exp $ */
2 /* PLIP: A parallel port "network" driver for Linux. */
3 /* This driver is for parallel port with 5-bit cable (LapLink (R) cable). */
4 /*
5 * Authors: Donald Becker <becker@scyld.com>
6 * Tommy Thorn <thorn@daimi.aau.dk>
7 * Tanabe Hiroyasu <hiro@sanpo.t.u-tokyo.ac.jp>
8 * Alan Cox <gw4pts@gw4pts.ampr.org>
9 * Peter Bauer <100136.3530@compuserve.com>
10 * Niibe Yutaka <gniibe@mri.co.jp>
11 * Nimrod Zimerman <zimerman@mailandnews.com>
13 * Enhancements:
14 * Modularization and ifreq/ifmap support by Alan Cox.
15 * Rewritten by Niibe Yutaka.
16 * parport-sharing awareness code by Philip Blundell.
17 * SMP locking by Niibe Yutaka.
18 * Support for parallel ports with no IRQ (poll mode),
19 * Modifications to use the parallel port API
20 * by Nimrod Zimerman.
22 * Fixes:
23 * Niibe Yutaka
24 * - Module initialization.
25 * - MTU fix.
26 * - Make sure other end is OK, before sending a packet.
27 * - Fix immediate timer problem.
29 * Al Viro
30 * - Changed {enable,disable}_irq handling to make it work
31 * with new ("stack") semantics.
33 * This program is free software; you can redistribute it and/or
34 * modify it under the terms of the GNU General Public License
35 * as published by the Free Software Foundation; either version
36 * 2 of the License, or (at your option) any later version.
40 * Original version and the name 'PLIP' from Donald Becker <becker@scyld.com>
41 * inspired by Russ Nelson's parallel port packet driver.
43 * NOTE:
44 * Tanabe Hiroyasu had changed the protocol, and it was in Linux v1.0.
45 * Because of the necessity to communicate to DOS machines with the
46 * Crynwr packet driver, Peter Bauer changed the protocol again
47 * back to original protocol.
49 * This version follows original PLIP protocol.
50 * So, this PLIP can't communicate the PLIP of Linux v1.0.
54 * To use with DOS box, please do (Turn on ARP switch):
55 * # ifconfig plip[0-2] arp
57 static const char version[] = "NET3 PLIP version 2.4-parport gniibe@mri.co.jp\n";
60 Sources:
61 Ideas and protocols came from Russ Nelson's <nelson@crynwr.com>
62 "parallel.asm" parallel port packet driver.
64 The "Crynwr" parallel port standard specifies the following protocol:
65 Trigger by sending nibble '0x8' (this causes interrupt on other end)
66 count-low octet
67 count-high octet
68 ... data octets
69 checksum octet
70 Each octet is sent as <wait for rx. '0x1?'> <send 0x10+(octet&0x0F)>
71 <wait for rx. '0x0?'> <send 0x00+((octet>>4)&0x0F)>
73 The packet is encapsulated as if it were ethernet.
75 The cable used is a de facto standard parallel null cable -- sold as
76 a "LapLink" cable by various places. You'll need a 12-conductor cable to
77 make one yourself. The wiring is:
78 SLCTIN 17 - 17
79 GROUND 25 - 25
80 D0->ERROR 2 - 15 15 - 2
81 D1->SLCT 3 - 13 13 - 3
82 D2->PAPOUT 4 - 12 12 - 4
83 D3->ACK 5 - 10 10 - 5
84 D4->BUSY 6 - 11 11 - 6
85 Do not connect the other pins. They are
86 D5,D6,D7 are 7,8,9
87 STROBE is 1, FEED is 14, INIT is 16
88 extra grounds are 18,19,20,21,22,23,24
91 #include <linux/module.h>
92 #include <linux/kernel.h>
93 #include <linux/types.h>
94 #include <linux/fcntl.h>
95 #include <linux/interrupt.h>
96 #include <linux/string.h>
97 #include <linux/slab.h>
98 #include <linux/if_ether.h>
99 #include <linux/in.h>
100 #include <linux/errno.h>
101 #include <linux/delay.h>
102 #include <linux/init.h>
103 #include <linux/netdevice.h>
104 #include <linux/etherdevice.h>
105 #include <linux/inetdevice.h>
106 #include <linux/skbuff.h>
107 #include <linux/if_plip.h>
108 #include <linux/workqueue.h>
109 #include <linux/spinlock.h>
110 #include <linux/completion.h>
111 #include <linux/parport.h>
112 #include <linux/bitops.h>
114 #include <net/neighbour.h>
116 #include <asm/irq.h>
117 #include <asm/byteorder.h>
119 /* Maximum number of devices to support. */
120 #define PLIP_MAX 8
122 /* Use 0 for production, 1 for verification, >2 for debug */
123 #ifndef NET_DEBUG
124 #define NET_DEBUG 1
125 #endif
126 static const unsigned int net_debug = NET_DEBUG;
128 #define ENABLE(irq) if (irq != -1) enable_irq(irq)
129 #define DISABLE(irq) if (irq != -1) disable_irq(irq)
131 /* In micro second */
132 #define PLIP_DELAY_UNIT 1
134 /* Connection time out = PLIP_TRIGGER_WAIT * PLIP_DELAY_UNIT usec */
135 #define PLIP_TRIGGER_WAIT 500
137 /* Nibble time out = PLIP_NIBBLE_WAIT * PLIP_DELAY_UNIT usec */
138 #define PLIP_NIBBLE_WAIT 3000
140 /* Bottom halves */
141 static void plip_kick_bh(struct work_struct *work);
142 static void plip_bh(struct work_struct *work);
143 static void plip_timer_bh(struct work_struct *work);
145 /* Interrupt handler */
146 static void plip_interrupt(void *dev_id);
148 /* Functions for DEV methods */
149 static int plip_tx_packet(struct sk_buff *skb, struct net_device *dev);
150 static int plip_hard_header(struct sk_buff *skb, struct net_device *dev,
151 unsigned short type, const void *daddr,
152 const void *saddr, unsigned len);
153 static int plip_hard_header_cache(const struct neighbour *neigh,
154 struct hh_cache *hh, __be16 type);
155 static int plip_open(struct net_device *dev);
156 static int plip_close(struct net_device *dev);
157 static int plip_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
158 static int plip_preempt(void *handle);
159 static void plip_wakeup(void *handle);
161 enum plip_connection_state {
162 PLIP_CN_NONE=0,
163 PLIP_CN_RECEIVE,
164 PLIP_CN_SEND,
165 PLIP_CN_CLOSING,
166 PLIP_CN_ERROR
169 enum plip_packet_state {
170 PLIP_PK_DONE=0,
171 PLIP_PK_TRIGGER,
172 PLIP_PK_LENGTH_LSB,
173 PLIP_PK_LENGTH_MSB,
174 PLIP_PK_DATA,
175 PLIP_PK_CHECKSUM
178 enum plip_nibble_state {
179 PLIP_NB_BEGIN,
180 PLIP_NB_1,
181 PLIP_NB_2,
184 struct plip_local {
185 enum plip_packet_state state;
186 enum plip_nibble_state nibble;
187 union {
188 struct {
189 #if defined(__LITTLE_ENDIAN)
190 unsigned char lsb;
191 unsigned char msb;
192 #elif defined(__BIG_ENDIAN)
193 unsigned char msb;
194 unsigned char lsb;
195 #else
196 #error "Please fix the endianness defines in <asm/byteorder.h>"
197 #endif
198 } b;
199 unsigned short h;
200 } length;
201 unsigned short byte;
202 unsigned char checksum;
203 unsigned char data;
204 struct sk_buff *skb;
207 struct net_local {
208 struct net_device *dev;
209 struct work_struct immediate;
210 struct delayed_work deferred;
211 struct delayed_work timer;
212 struct plip_local snd_data;
213 struct plip_local rcv_data;
214 struct pardevice *pardev;
215 unsigned long trigger;
216 unsigned long nibble;
217 enum plip_connection_state connection;
218 unsigned short timeout_count;
219 int is_deferred;
220 int port_owner;
221 int should_relinquish;
222 spinlock_t lock;
223 atomic_t kill_timer;
224 struct completion killed_timer_cmp;
227 static inline void enable_parport_interrupts (struct net_device *dev)
229 if (dev->irq != -1)
231 struct parport *port =
232 ((struct net_local *)netdev_priv(dev))->pardev->port;
233 port->ops->enable_irq (port);
237 static inline void disable_parport_interrupts (struct net_device *dev)
239 if (dev->irq != -1)
241 struct parport *port =
242 ((struct net_local *)netdev_priv(dev))->pardev->port;
243 port->ops->disable_irq (port);
247 static inline void write_data (struct net_device *dev, unsigned char data)
249 struct parport *port =
250 ((struct net_local *)netdev_priv(dev))->pardev->port;
252 port->ops->write_data (port, data);
255 static inline unsigned char read_status (struct net_device *dev)
257 struct parport *port =
258 ((struct net_local *)netdev_priv(dev))->pardev->port;
260 return port->ops->read_status (port);
263 static const struct header_ops plip_header_ops = {
264 .create = plip_hard_header,
265 .cache = plip_hard_header_cache,
268 static const struct net_device_ops plip_netdev_ops = {
269 .ndo_open = plip_open,
270 .ndo_stop = plip_close,
271 .ndo_start_xmit = plip_tx_packet,
272 .ndo_do_ioctl = plip_ioctl,
273 .ndo_set_mac_address = eth_mac_addr,
274 .ndo_validate_addr = eth_validate_addr,
277 /* Entry point of PLIP driver.
278 Probe the hardware, and register/initialize the driver.
280 PLIP is rather weird, because of the way it interacts with the parport
281 system. It is _not_ initialised from Space.c. Instead, plip_init()
282 is called, and that function makes up a "struct net_device" for each port, and
283 then calls us here.
286 static void
287 plip_init_netdev(struct net_device *dev)
289 struct net_local *nl = netdev_priv(dev);
291 /* Then, override parts of it */
292 dev->tx_queue_len = 10;
293 dev->flags = IFF_POINTOPOINT|IFF_NOARP;
294 memset(dev->dev_addr, 0xfc, ETH_ALEN);
296 dev->netdev_ops = &plip_netdev_ops;
297 dev->header_ops = &plip_header_ops;
300 nl->port_owner = 0;
302 /* Initialize constants */
303 nl->trigger = PLIP_TRIGGER_WAIT;
304 nl->nibble = PLIP_NIBBLE_WAIT;
306 /* Initialize task queue structures */
307 INIT_WORK(&nl->immediate, plip_bh);
308 INIT_DELAYED_WORK(&nl->deferred, plip_kick_bh);
310 if (dev->irq == -1)
311 INIT_DELAYED_WORK(&nl->timer, plip_timer_bh);
313 spin_lock_init(&nl->lock);
316 /* Bottom half handler for the delayed request.
317 This routine is kicked by do_timer().
318 Request `plip_bh' to be invoked. */
319 static void
320 plip_kick_bh(struct work_struct *work)
322 struct net_local *nl =
323 container_of(work, struct net_local, deferred.work);
325 if (nl->is_deferred)
326 schedule_work(&nl->immediate);
329 /* Forward declarations of internal routines */
330 static int plip_none(struct net_device *, struct net_local *,
331 struct plip_local *, struct plip_local *);
332 static int plip_receive_packet(struct net_device *, struct net_local *,
333 struct plip_local *, struct plip_local *);
334 static int plip_send_packet(struct net_device *, struct net_local *,
335 struct plip_local *, struct plip_local *);
336 static int plip_connection_close(struct net_device *, struct net_local *,
337 struct plip_local *, struct plip_local *);
338 static int plip_error(struct net_device *, struct net_local *,
339 struct plip_local *, struct plip_local *);
340 static int plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
341 struct plip_local *snd,
342 struct plip_local *rcv,
343 int error);
345 #define OK 0
346 #define TIMEOUT 1
347 #define ERROR 2
348 #define HS_TIMEOUT 3
350 typedef int (*plip_func)(struct net_device *dev, struct net_local *nl,
351 struct plip_local *snd, struct plip_local *rcv);
353 static const plip_func connection_state_table[] =
355 plip_none,
356 plip_receive_packet,
357 plip_send_packet,
358 plip_connection_close,
359 plip_error
362 /* Bottom half handler of PLIP. */
363 static void
364 plip_bh(struct work_struct *work)
366 struct net_local *nl = container_of(work, struct net_local, immediate);
367 struct plip_local *snd = &nl->snd_data;
368 struct plip_local *rcv = &nl->rcv_data;
369 plip_func f;
370 int r;
372 nl->is_deferred = 0;
373 f = connection_state_table[nl->connection];
374 if ((r = (*f)(nl->dev, nl, snd, rcv)) != OK &&
375 (r = plip_bh_timeout_error(nl->dev, nl, snd, rcv, r)) != OK) {
376 nl->is_deferred = 1;
377 schedule_delayed_work(&nl->deferred, 1);
381 static void
382 plip_timer_bh(struct work_struct *work)
384 struct net_local *nl =
385 container_of(work, struct net_local, timer.work);
387 if (!(atomic_read (&nl->kill_timer))) {
388 plip_interrupt (nl->dev);
390 schedule_delayed_work(&nl->timer, 1);
392 else {
393 complete(&nl->killed_timer_cmp);
397 static int
398 plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
399 struct plip_local *snd, struct plip_local *rcv,
400 int error)
402 unsigned char c0;
404 * This is tricky. If we got here from the beginning of send (either
405 * with ERROR or HS_TIMEOUT) we have IRQ enabled. Otherwise it's
406 * already disabled. With the old variant of {enable,disable}_irq()
407 * extra disable_irq() was a no-op. Now it became mortal - it's
408 * unbalanced and thus we'll never re-enable IRQ (until rmmod plip,
409 * that is). So we have to treat HS_TIMEOUT and ERROR from send
410 * in a special way.
413 spin_lock_irq(&nl->lock);
414 if (nl->connection == PLIP_CN_SEND) {
416 if (error != ERROR) { /* Timeout */
417 nl->timeout_count++;
418 if ((error == HS_TIMEOUT && nl->timeout_count <= 10) ||
419 nl->timeout_count <= 3) {
420 spin_unlock_irq(&nl->lock);
421 /* Try again later */
422 return TIMEOUT;
424 c0 = read_status(dev);
425 printk(KERN_WARNING "%s: transmit timeout(%d,%02x)\n",
426 dev->name, snd->state, c0);
427 } else
428 error = HS_TIMEOUT;
429 dev->stats.tx_errors++;
430 dev->stats.tx_aborted_errors++;
431 } else if (nl->connection == PLIP_CN_RECEIVE) {
432 if (rcv->state == PLIP_PK_TRIGGER) {
433 /* Transmission was interrupted. */
434 spin_unlock_irq(&nl->lock);
435 return OK;
437 if (error != ERROR) { /* Timeout */
438 if (++nl->timeout_count <= 3) {
439 spin_unlock_irq(&nl->lock);
440 /* Try again later */
441 return TIMEOUT;
443 c0 = read_status(dev);
444 printk(KERN_WARNING "%s: receive timeout(%d,%02x)\n",
445 dev->name, rcv->state, c0);
447 dev->stats.rx_dropped++;
449 rcv->state = PLIP_PK_DONE;
450 if (rcv->skb) {
451 kfree_skb(rcv->skb);
452 rcv->skb = NULL;
454 snd->state = PLIP_PK_DONE;
455 if (snd->skb) {
456 dev_kfree_skb(snd->skb);
457 snd->skb = NULL;
459 spin_unlock_irq(&nl->lock);
460 if (error == HS_TIMEOUT) {
461 DISABLE(dev->irq);
462 synchronize_irq(dev->irq);
464 disable_parport_interrupts (dev);
465 netif_stop_queue (dev);
466 nl->connection = PLIP_CN_ERROR;
467 write_data (dev, 0x00);
469 return TIMEOUT;
472 static int
473 plip_none(struct net_device *dev, struct net_local *nl,
474 struct plip_local *snd, struct plip_local *rcv)
476 return OK;
479 /* PLIP_RECEIVE --- receive a byte(two nibbles)
480 Returns OK on success, TIMEOUT on timeout */
481 static inline int
482 plip_receive(unsigned short nibble_timeout, struct net_device *dev,
483 enum plip_nibble_state *ns_p, unsigned char *data_p)
485 unsigned char c0, c1;
486 unsigned int cx;
488 switch (*ns_p) {
489 case PLIP_NB_BEGIN:
490 cx = nibble_timeout;
491 while (1) {
492 c0 = read_status(dev);
493 udelay(PLIP_DELAY_UNIT);
494 if ((c0 & 0x80) == 0) {
495 c1 = read_status(dev);
496 if (c0 == c1)
497 break;
499 if (--cx == 0)
500 return TIMEOUT;
502 *data_p = (c0 >> 3) & 0x0f;
503 write_data (dev, 0x10); /* send ACK */
504 *ns_p = PLIP_NB_1;
505 /* fall through */
507 case PLIP_NB_1:
508 cx = nibble_timeout;
509 while (1) {
510 c0 = read_status(dev);
511 udelay(PLIP_DELAY_UNIT);
512 if (c0 & 0x80) {
513 c1 = read_status(dev);
514 if (c0 == c1)
515 break;
517 if (--cx == 0)
518 return TIMEOUT;
520 *data_p |= (c0 << 1) & 0xf0;
521 write_data (dev, 0x00); /* send ACK */
522 *ns_p = PLIP_NB_BEGIN;
523 case PLIP_NB_2:
524 break;
526 return OK;
530 * Determine the packet's protocol ID. The rule here is that we
531 * assume 802.3 if the type field is short enough to be a length.
532 * This is normal practice and works for any 'now in use' protocol.
534 * PLIP is ethernet ish but the daddr might not be valid if unicast.
535 * PLIP fortunately has no bus architecture (its Point-to-point).
537 * We can't fix the daddr thing as that quirk (more bug) is embedded
538 * in far too many old systems not all even running Linux.
541 static __be16 plip_type_trans(struct sk_buff *skb, struct net_device *dev)
543 struct ethhdr *eth;
544 unsigned char *rawp;
546 skb_reset_mac_header(skb);
547 skb_pull(skb,dev->hard_header_len);
548 eth = eth_hdr(skb);
550 if(is_multicast_ether_addr(eth->h_dest))
552 if(ether_addr_equal_64bits(eth->h_dest, dev->broadcast))
553 skb->pkt_type=PACKET_BROADCAST;
554 else
555 skb->pkt_type=PACKET_MULTICAST;
559 * This ALLMULTI check should be redundant by 1.4
560 * so don't forget to remove it.
563 if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN)
564 return eth->h_proto;
566 rawp = skb->data;
569 * This is a magic hack to spot IPX packets. Older Novell breaks
570 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
571 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
572 * won't work for fault tolerant netware but does for the rest.
574 if (*(unsigned short *)rawp == 0xFFFF)
575 return htons(ETH_P_802_3);
578 * Real 802.2 LLC
580 return htons(ETH_P_802_2);
583 /* PLIP_RECEIVE_PACKET --- receive a packet */
584 static int
585 plip_receive_packet(struct net_device *dev, struct net_local *nl,
586 struct plip_local *snd, struct plip_local *rcv)
588 unsigned short nibble_timeout = nl->nibble;
589 unsigned char *lbuf;
591 switch (rcv->state) {
592 case PLIP_PK_TRIGGER:
593 DISABLE(dev->irq);
594 /* Don't need to synchronize irq, as we can safely ignore it */
595 disable_parport_interrupts (dev);
596 write_data (dev, 0x01); /* send ACK */
597 if (net_debug > 2)
598 printk(KERN_DEBUG "%s: receive start\n", dev->name);
599 rcv->state = PLIP_PK_LENGTH_LSB;
600 rcv->nibble = PLIP_NB_BEGIN;
601 /* fall through */
603 case PLIP_PK_LENGTH_LSB:
604 if (snd->state != PLIP_PK_DONE) {
605 if (plip_receive(nl->trigger, dev,
606 &rcv->nibble, &rcv->length.b.lsb)) {
607 /* collision, here dev->tbusy == 1 */
608 rcv->state = PLIP_PK_DONE;
609 nl->is_deferred = 1;
610 nl->connection = PLIP_CN_SEND;
611 schedule_delayed_work(&nl->deferred, 1);
612 enable_parport_interrupts (dev);
613 ENABLE(dev->irq);
614 return OK;
616 } else {
617 if (plip_receive(nibble_timeout, dev,
618 &rcv->nibble, &rcv->length.b.lsb))
619 return TIMEOUT;
621 rcv->state = PLIP_PK_LENGTH_MSB;
622 /* fall through */
624 case PLIP_PK_LENGTH_MSB:
625 if (plip_receive(nibble_timeout, dev,
626 &rcv->nibble, &rcv->length.b.msb))
627 return TIMEOUT;
628 if (rcv->length.h > dev->mtu + dev->hard_header_len ||
629 rcv->length.h < 8) {
630 printk(KERN_WARNING "%s: bogus packet size %d.\n", dev->name, rcv->length.h);
631 return ERROR;
633 /* Malloc up new buffer. */
634 rcv->skb = dev_alloc_skb(rcv->length.h + 2);
635 if (rcv->skb == NULL) {
636 printk(KERN_ERR "%s: Memory squeeze.\n", dev->name);
637 return ERROR;
639 skb_reserve(rcv->skb, 2); /* Align IP on 16 byte boundaries */
640 skb_put(rcv->skb,rcv->length.h);
641 rcv->skb->dev = dev;
642 rcv->state = PLIP_PK_DATA;
643 rcv->byte = 0;
644 rcv->checksum = 0;
645 /* fall through */
647 case PLIP_PK_DATA:
648 lbuf = rcv->skb->data;
649 do {
650 if (plip_receive(nibble_timeout, dev,
651 &rcv->nibble, &lbuf[rcv->byte]))
652 return TIMEOUT;
653 } while (++rcv->byte < rcv->length.h);
654 do {
655 rcv->checksum += lbuf[--rcv->byte];
656 } while (rcv->byte);
657 rcv->state = PLIP_PK_CHECKSUM;
658 /* fall through */
660 case PLIP_PK_CHECKSUM:
661 if (plip_receive(nibble_timeout, dev,
662 &rcv->nibble, &rcv->data))
663 return TIMEOUT;
664 if (rcv->data != rcv->checksum) {
665 dev->stats.rx_crc_errors++;
666 if (net_debug)
667 printk(KERN_DEBUG "%s: checksum error\n", dev->name);
668 return ERROR;
670 rcv->state = PLIP_PK_DONE;
671 /* fall through */
673 case PLIP_PK_DONE:
674 /* Inform the upper layer for the arrival of a packet. */
675 rcv->skb->protocol=plip_type_trans(rcv->skb, dev);
676 netif_rx_ni(rcv->skb);
677 dev->stats.rx_bytes += rcv->length.h;
678 dev->stats.rx_packets++;
679 rcv->skb = NULL;
680 if (net_debug > 2)
681 printk(KERN_DEBUG "%s: receive end\n", dev->name);
683 /* Close the connection. */
684 write_data (dev, 0x00);
685 spin_lock_irq(&nl->lock);
686 if (snd->state != PLIP_PK_DONE) {
687 nl->connection = PLIP_CN_SEND;
688 spin_unlock_irq(&nl->lock);
689 schedule_work(&nl->immediate);
690 enable_parport_interrupts (dev);
691 ENABLE(dev->irq);
692 return OK;
693 } else {
694 nl->connection = PLIP_CN_NONE;
695 spin_unlock_irq(&nl->lock);
696 enable_parport_interrupts (dev);
697 ENABLE(dev->irq);
698 return OK;
701 return OK;
704 /* PLIP_SEND --- send a byte (two nibbles)
705 Returns OK on success, TIMEOUT when timeout */
706 static inline int
707 plip_send(unsigned short nibble_timeout, struct net_device *dev,
708 enum plip_nibble_state *ns_p, unsigned char data)
710 unsigned char c0;
711 unsigned int cx;
713 switch (*ns_p) {
714 case PLIP_NB_BEGIN:
715 write_data (dev, data & 0x0f);
716 *ns_p = PLIP_NB_1;
717 /* fall through */
719 case PLIP_NB_1:
720 write_data (dev, 0x10 | (data & 0x0f));
721 cx = nibble_timeout;
722 while (1) {
723 c0 = read_status(dev);
724 if ((c0 & 0x80) == 0)
725 break;
726 if (--cx == 0)
727 return TIMEOUT;
728 udelay(PLIP_DELAY_UNIT);
730 write_data (dev, 0x10 | (data >> 4));
731 *ns_p = PLIP_NB_2;
732 /* fall through */
734 case PLIP_NB_2:
735 write_data (dev, (data >> 4));
736 cx = nibble_timeout;
737 while (1) {
738 c0 = read_status(dev);
739 if (c0 & 0x80)
740 break;
741 if (--cx == 0)
742 return TIMEOUT;
743 udelay(PLIP_DELAY_UNIT);
745 *ns_p = PLIP_NB_BEGIN;
746 return OK;
748 return OK;
751 /* PLIP_SEND_PACKET --- send a packet */
752 static int
753 plip_send_packet(struct net_device *dev, struct net_local *nl,
754 struct plip_local *snd, struct plip_local *rcv)
756 unsigned short nibble_timeout = nl->nibble;
757 unsigned char *lbuf;
758 unsigned char c0;
759 unsigned int cx;
761 if (snd->skb == NULL || (lbuf = snd->skb->data) == NULL) {
762 printk(KERN_DEBUG "%s: send skb lost\n", dev->name);
763 snd->state = PLIP_PK_DONE;
764 snd->skb = NULL;
765 return ERROR;
768 switch (snd->state) {
769 case PLIP_PK_TRIGGER:
770 if ((read_status(dev) & 0xf8) != 0x80)
771 return HS_TIMEOUT;
773 /* Trigger remote rx interrupt. */
774 write_data (dev, 0x08);
775 cx = nl->trigger;
776 while (1) {
777 udelay(PLIP_DELAY_UNIT);
778 spin_lock_irq(&nl->lock);
779 if (nl->connection == PLIP_CN_RECEIVE) {
780 spin_unlock_irq(&nl->lock);
781 /* Interrupted. */
782 dev->stats.collisions++;
783 return OK;
785 c0 = read_status(dev);
786 if (c0 & 0x08) {
787 spin_unlock_irq(&nl->lock);
788 DISABLE(dev->irq);
789 synchronize_irq(dev->irq);
790 if (nl->connection == PLIP_CN_RECEIVE) {
791 /* Interrupted.
792 We don't need to enable irq,
793 as it is soon disabled. */
794 /* Yes, we do. New variant of
795 {enable,disable}_irq *counts*
796 them. -- AV */
797 ENABLE(dev->irq);
798 dev->stats.collisions++;
799 return OK;
801 disable_parport_interrupts (dev);
802 if (net_debug > 2)
803 printk(KERN_DEBUG "%s: send start\n", dev->name);
804 snd->state = PLIP_PK_LENGTH_LSB;
805 snd->nibble = PLIP_NB_BEGIN;
806 nl->timeout_count = 0;
807 break;
809 spin_unlock_irq(&nl->lock);
810 if (--cx == 0) {
811 write_data (dev, 0x00);
812 return HS_TIMEOUT;
816 case PLIP_PK_LENGTH_LSB:
817 if (plip_send(nibble_timeout, dev,
818 &snd->nibble, snd->length.b.lsb))
819 return TIMEOUT;
820 snd->state = PLIP_PK_LENGTH_MSB;
821 /* fall through */
823 case PLIP_PK_LENGTH_MSB:
824 if (plip_send(nibble_timeout, dev,
825 &snd->nibble, snd->length.b.msb))
826 return TIMEOUT;
827 snd->state = PLIP_PK_DATA;
828 snd->byte = 0;
829 snd->checksum = 0;
830 /* fall through */
832 case PLIP_PK_DATA:
833 do {
834 if (plip_send(nibble_timeout, dev,
835 &snd->nibble, lbuf[snd->byte]))
836 return TIMEOUT;
837 } while (++snd->byte < snd->length.h);
838 do {
839 snd->checksum += lbuf[--snd->byte];
840 } while (snd->byte);
841 snd->state = PLIP_PK_CHECKSUM;
842 /* fall through */
844 case PLIP_PK_CHECKSUM:
845 if (plip_send(nibble_timeout, dev,
846 &snd->nibble, snd->checksum))
847 return TIMEOUT;
849 dev->stats.tx_bytes += snd->skb->len;
850 dev_kfree_skb(snd->skb);
851 dev->stats.tx_packets++;
852 snd->state = PLIP_PK_DONE;
853 /* fall through */
855 case PLIP_PK_DONE:
856 /* Close the connection */
857 write_data (dev, 0x00);
858 snd->skb = NULL;
859 if (net_debug > 2)
860 printk(KERN_DEBUG "%s: send end\n", dev->name);
861 nl->connection = PLIP_CN_CLOSING;
862 nl->is_deferred = 1;
863 schedule_delayed_work(&nl->deferred, 1);
864 enable_parport_interrupts (dev);
865 ENABLE(dev->irq);
866 return OK;
868 return OK;
871 static int
872 plip_connection_close(struct net_device *dev, struct net_local *nl,
873 struct plip_local *snd, struct plip_local *rcv)
875 spin_lock_irq(&nl->lock);
876 if (nl->connection == PLIP_CN_CLOSING) {
877 nl->connection = PLIP_CN_NONE;
878 netif_wake_queue (dev);
880 spin_unlock_irq(&nl->lock);
881 if (nl->should_relinquish) {
882 nl->should_relinquish = nl->port_owner = 0;
883 parport_release(nl->pardev);
885 return OK;
888 /* PLIP_ERROR --- wait till other end settled */
889 static int
890 plip_error(struct net_device *dev, struct net_local *nl,
891 struct plip_local *snd, struct plip_local *rcv)
893 unsigned char status;
895 status = read_status(dev);
896 if ((status & 0xf8) == 0x80) {
897 if (net_debug > 2)
898 printk(KERN_DEBUG "%s: reset interface.\n", dev->name);
899 nl->connection = PLIP_CN_NONE;
900 nl->should_relinquish = 0;
901 netif_start_queue (dev);
902 enable_parport_interrupts (dev);
903 ENABLE(dev->irq);
904 netif_wake_queue (dev);
905 } else {
906 nl->is_deferred = 1;
907 schedule_delayed_work(&nl->deferred, 1);
910 return OK;
913 /* Handle the parallel port interrupts. */
914 static void
915 plip_interrupt(void *dev_id)
917 struct net_device *dev = dev_id;
918 struct net_local *nl;
919 struct plip_local *rcv;
920 unsigned char c0;
921 unsigned long flags;
923 nl = netdev_priv(dev);
924 rcv = &nl->rcv_data;
926 spin_lock_irqsave (&nl->lock, flags);
928 c0 = read_status(dev);
929 if ((c0 & 0xf8) != 0xc0) {
930 if ((dev->irq != -1) && (net_debug > 1))
931 printk(KERN_DEBUG "%s: spurious interrupt\n", dev->name);
932 spin_unlock_irqrestore (&nl->lock, flags);
933 return;
936 if (net_debug > 3)
937 printk(KERN_DEBUG "%s: interrupt.\n", dev->name);
939 switch (nl->connection) {
940 case PLIP_CN_CLOSING:
941 netif_wake_queue (dev);
942 /* fall through */
943 case PLIP_CN_NONE:
944 case PLIP_CN_SEND:
945 rcv->state = PLIP_PK_TRIGGER;
946 nl->connection = PLIP_CN_RECEIVE;
947 nl->timeout_count = 0;
948 schedule_work(&nl->immediate);
949 break;
951 case PLIP_CN_RECEIVE:
952 /* May occur because there is race condition
953 around test and set of dev->interrupt.
954 Ignore this interrupt. */
955 break;
957 case PLIP_CN_ERROR:
958 printk(KERN_ERR "%s: receive interrupt in error state\n", dev->name);
959 break;
962 spin_unlock_irqrestore(&nl->lock, flags);
965 static int
966 plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
968 struct net_local *nl = netdev_priv(dev);
969 struct plip_local *snd = &nl->snd_data;
971 if (netif_queue_stopped(dev))
972 return NETDEV_TX_BUSY;
974 /* We may need to grab the bus */
975 if (!nl->port_owner) {
976 if (parport_claim(nl->pardev))
977 return NETDEV_TX_BUSY;
978 nl->port_owner = 1;
981 netif_stop_queue (dev);
983 if (skb->len > dev->mtu + dev->hard_header_len) {
984 printk(KERN_WARNING "%s: packet too big, %d.\n", dev->name, (int)skb->len);
985 netif_start_queue (dev);
986 return NETDEV_TX_BUSY;
989 if (net_debug > 2)
990 printk(KERN_DEBUG "%s: send request\n", dev->name);
992 spin_lock_irq(&nl->lock);
993 snd->skb = skb;
994 snd->length.h = skb->len;
995 snd->state = PLIP_PK_TRIGGER;
996 if (nl->connection == PLIP_CN_NONE) {
997 nl->connection = PLIP_CN_SEND;
998 nl->timeout_count = 0;
1000 schedule_work(&nl->immediate);
1001 spin_unlock_irq(&nl->lock);
1003 return NETDEV_TX_OK;
1006 static void
1007 plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
1009 const struct in_device *in_dev;
1011 rcu_read_lock();
1012 in_dev = __in_dev_get_rcu(dev);
1013 if (in_dev) {
1014 /* Any address will do - we take the first */
1015 const struct in_ifaddr *ifa = in_dev->ifa_list;
1016 if (ifa) {
1017 memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
1018 memset(eth->h_dest, 0xfc, 2);
1019 memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
1022 rcu_read_unlock();
1025 static int
1026 plip_hard_header(struct sk_buff *skb, struct net_device *dev,
1027 unsigned short type, const void *daddr,
1028 const void *saddr, unsigned len)
1030 int ret;
1032 ret = eth_header(skb, dev, type, daddr, saddr, len);
1033 if (ret >= 0)
1034 plip_rewrite_address (dev, (struct ethhdr *)skb->data);
1036 return ret;
1039 static int plip_hard_header_cache(const struct neighbour *neigh,
1040 struct hh_cache *hh, __be16 type)
1042 int ret;
1044 ret = eth_header_cache(neigh, hh, type);
1045 if (ret == 0) {
1046 struct ethhdr *eth;
1048 eth = (struct ethhdr*)(((u8*)hh->hh_data) +
1049 HH_DATA_OFF(sizeof(*eth)));
1050 plip_rewrite_address (neigh->dev, eth);
1053 return ret;
1056 /* Open/initialize the board. This is called (in the current kernel)
1057 sometime after booting when the 'ifconfig' program is run.
1059 This routine gets exclusive access to the parallel port by allocating
1060 its IRQ line.
1062 static int
1063 plip_open(struct net_device *dev)
1065 struct net_local *nl = netdev_priv(dev);
1066 struct in_device *in_dev;
1068 /* Grab the port */
1069 if (!nl->port_owner) {
1070 if (parport_claim(nl->pardev)) return -EAGAIN;
1071 nl->port_owner = 1;
1074 nl->should_relinquish = 0;
1076 /* Clear the data port. */
1077 write_data (dev, 0x00);
1079 /* Enable rx interrupt. */
1080 enable_parport_interrupts (dev);
1081 if (dev->irq == -1)
1083 atomic_set (&nl->kill_timer, 0);
1084 schedule_delayed_work(&nl->timer, 1);
1087 /* Initialize the state machine. */
1088 nl->rcv_data.state = nl->snd_data.state = PLIP_PK_DONE;
1089 nl->rcv_data.skb = nl->snd_data.skb = NULL;
1090 nl->connection = PLIP_CN_NONE;
1091 nl->is_deferred = 0;
1093 /* Fill in the MAC-level header.
1094 We used to abuse dev->broadcast to store the point-to-point
1095 MAC address, but we no longer do it. Instead, we fetch the
1096 interface address whenever it is needed, which is cheap enough
1097 because we use the hh_cache. Actually, abusing dev->broadcast
1098 didn't work, because when using plip_open the point-to-point
1099 address isn't yet known.
1100 PLIP doesn't have a real MAC address, but we need it to be
1101 DOS compatible, and to properly support taps (otherwise,
1102 when the device address isn't identical to the address of a
1103 received frame, the kernel incorrectly drops it). */
1105 in_dev=__in_dev_get_rtnl(dev);
1106 if (in_dev) {
1107 /* Any address will do - we take the first. We already
1108 have the first two bytes filled with 0xfc, from
1109 plip_init_dev(). */
1110 struct in_ifaddr *ifa=in_dev->ifa_list;
1111 if (ifa != NULL) {
1112 memcpy(dev->dev_addr+2, &ifa->ifa_local, 4);
1116 netif_start_queue (dev);
1118 return 0;
1121 /* The inverse routine to plip_open (). */
1122 static int
1123 plip_close(struct net_device *dev)
1125 struct net_local *nl = netdev_priv(dev);
1126 struct plip_local *snd = &nl->snd_data;
1127 struct plip_local *rcv = &nl->rcv_data;
1129 netif_stop_queue (dev);
1130 DISABLE(dev->irq);
1131 synchronize_irq(dev->irq);
1133 if (dev->irq == -1)
1135 init_completion(&nl->killed_timer_cmp);
1136 atomic_set (&nl->kill_timer, 1);
1137 wait_for_completion(&nl->killed_timer_cmp);
1140 #ifdef NOTDEF
1141 outb(0x00, PAR_DATA(dev));
1142 #endif
1143 nl->is_deferred = 0;
1144 nl->connection = PLIP_CN_NONE;
1145 if (nl->port_owner) {
1146 parport_release(nl->pardev);
1147 nl->port_owner = 0;
1150 snd->state = PLIP_PK_DONE;
1151 if (snd->skb) {
1152 dev_kfree_skb(snd->skb);
1153 snd->skb = NULL;
1155 rcv->state = PLIP_PK_DONE;
1156 if (rcv->skb) {
1157 kfree_skb(rcv->skb);
1158 rcv->skb = NULL;
1161 #ifdef NOTDEF
1162 /* Reset. */
1163 outb(0x00, PAR_CONTROL(dev));
1164 #endif
1165 return 0;
1168 static int
1169 plip_preempt(void *handle)
1171 struct net_device *dev = (struct net_device *)handle;
1172 struct net_local *nl = netdev_priv(dev);
1174 /* Stand our ground if a datagram is on the wire */
1175 if (nl->connection != PLIP_CN_NONE) {
1176 nl->should_relinquish = 1;
1177 return 1;
1180 nl->port_owner = 0; /* Remember that we released the bus */
1181 return 0;
1184 static void
1185 plip_wakeup(void *handle)
1187 struct net_device *dev = (struct net_device *)handle;
1188 struct net_local *nl = netdev_priv(dev);
1190 if (nl->port_owner) {
1191 /* Why are we being woken up? */
1192 printk(KERN_DEBUG "%s: why am I being woken up?\n", dev->name);
1193 if (!parport_claim(nl->pardev))
1194 /* bus_owner is already set (but why?) */
1195 printk(KERN_DEBUG "%s: I'm broken.\n", dev->name);
1196 else
1197 return;
1200 if (!(dev->flags & IFF_UP))
1201 /* Don't need the port when the interface is down */
1202 return;
1204 if (!parport_claim(nl->pardev)) {
1205 nl->port_owner = 1;
1206 /* Clear the data port. */
1207 write_data (dev, 0x00);
1211 static int
1212 plip_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1214 struct net_local *nl = netdev_priv(dev);
1215 struct plipconf *pc = (struct plipconf *) &rq->ifr_ifru;
1217 if (cmd != SIOCDEVPLIP)
1218 return -EOPNOTSUPP;
1220 switch(pc->pcmd) {
1221 case PLIP_GET_TIMEOUT:
1222 pc->trigger = nl->trigger;
1223 pc->nibble = nl->nibble;
1224 break;
1225 case PLIP_SET_TIMEOUT:
1226 if(!capable(CAP_NET_ADMIN))
1227 return -EPERM;
1228 nl->trigger = pc->trigger;
1229 nl->nibble = pc->nibble;
1230 break;
1231 default:
1232 return -EOPNOTSUPP;
1234 return 0;
1237 static int parport[PLIP_MAX] = { [0 ... PLIP_MAX-1] = -1 };
1238 static int timid;
1240 module_param_array(parport, int, NULL, 0);
1241 module_param(timid, int, 0);
1242 MODULE_PARM_DESC(parport, "List of parport device numbers to use by plip");
1244 static struct net_device *dev_plip[PLIP_MAX] = { NULL, };
1246 static inline int
1247 plip_searchfor(int list[], int a)
1249 int i;
1250 for (i = 0; i < PLIP_MAX && list[i] != -1; i++) {
1251 if (list[i] == a) return 1;
1253 return 0;
1256 /* plip_attach() is called (by the parport code) when a port is
1257 * available to use. */
1258 static void plip_attach (struct parport *port)
1260 static int unit;
1261 struct net_device *dev;
1262 struct net_local *nl;
1263 char name[IFNAMSIZ];
1264 struct pardev_cb plip_cb;
1266 if ((parport[0] == -1 && (!timid || !port->devices)) ||
1267 plip_searchfor(parport, port->number)) {
1268 if (unit == PLIP_MAX) {
1269 printk(KERN_ERR "plip: too many devices\n");
1270 return;
1273 sprintf(name, "plip%d", unit);
1274 dev = alloc_etherdev(sizeof(struct net_local));
1275 if (!dev)
1276 return;
1278 strcpy(dev->name, name);
1280 dev->irq = port->irq;
1281 dev->base_addr = port->base;
1282 if (port->irq == -1) {
1283 printk(KERN_INFO "plip: %s has no IRQ. Using IRQ-less mode,"
1284 "which is fairly inefficient!\n", port->name);
1287 nl = netdev_priv(dev);
1288 nl->dev = dev;
1290 memset(&plip_cb, 0, sizeof(plip_cb));
1291 plip_cb.private = dev;
1292 plip_cb.preempt = plip_preempt;
1293 plip_cb.wakeup = plip_wakeup;
1294 plip_cb.irq_func = plip_interrupt;
1296 nl->pardev = parport_register_dev_model(port, dev->name,
1297 &plip_cb, unit);
1299 if (!nl->pardev) {
1300 printk(KERN_ERR "%s: parport_register failed\n", name);
1301 goto err_free_dev;
1304 plip_init_netdev(dev);
1306 if (register_netdev(dev)) {
1307 printk(KERN_ERR "%s: network register failed\n", name);
1308 goto err_parport_unregister;
1311 printk(KERN_INFO "%s", version);
1312 if (dev->irq != -1)
1313 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1314 "using IRQ %d.\n",
1315 dev->name, dev->base_addr, dev->irq);
1316 else
1317 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1318 "not using IRQ.\n",
1319 dev->name, dev->base_addr);
1320 dev_plip[unit++] = dev;
1322 return;
1324 err_parport_unregister:
1325 parport_unregister_device(nl->pardev);
1326 err_free_dev:
1327 free_netdev(dev);
1330 /* plip_detach() is called (by the parport code) when a port is
1331 * no longer available to use. */
1332 static void plip_detach (struct parport *port)
1334 /* Nothing to do */
1337 static int plip_probe(struct pardevice *par_dev)
1339 struct device_driver *drv = par_dev->dev.driver;
1340 int len = strlen(drv->name);
1342 if (strncmp(par_dev->name, drv->name, len))
1343 return -ENODEV;
1345 return 0;
1348 static struct parport_driver plip_driver = {
1349 .name = "plip",
1350 .probe = plip_probe,
1351 .match_port = plip_attach,
1352 .detach = plip_detach,
1353 .devmodel = true,
1356 static void __exit plip_cleanup_module (void)
1358 struct net_device *dev;
1359 int i;
1361 for (i=0; i < PLIP_MAX; i++) {
1362 if ((dev = dev_plip[i])) {
1363 struct net_local *nl = netdev_priv(dev);
1364 unregister_netdev(dev);
1365 if (nl->port_owner)
1366 parport_release(nl->pardev);
1367 parport_unregister_device(nl->pardev);
1368 free_netdev(dev);
1369 dev_plip[i] = NULL;
1373 parport_unregister_driver(&plip_driver);
1376 #ifndef MODULE
1378 static int parport_ptr;
1380 static int __init plip_setup(char *str)
1382 int ints[4];
1384 str = get_options(str, ARRAY_SIZE(ints), ints);
1386 /* Ugh. */
1387 if (!strncmp(str, "parport", 7)) {
1388 int n = simple_strtoul(str+7, NULL, 10);
1389 if (parport_ptr < PLIP_MAX)
1390 parport[parport_ptr++] = n;
1391 else
1392 printk(KERN_INFO "plip: too many ports, %s ignored.\n",
1393 str);
1394 } else if (!strcmp(str, "timid")) {
1395 timid = 1;
1396 } else {
1397 if (ints[0] == 0 || ints[1] == 0) {
1398 /* disable driver on "plip=" or "plip=0" */
1399 parport[0] = -2;
1400 } else {
1401 printk(KERN_WARNING "warning: 'plip=0x%x' ignored\n",
1402 ints[1]);
1405 return 1;
1408 __setup("plip=", plip_setup);
1410 #endif /* !MODULE */
1412 static int __init plip_init (void)
1414 if (parport[0] == -2)
1415 return 0;
1417 if (parport[0] != -1 && timid) {
1418 printk(KERN_WARNING "plip: warning, ignoring `timid' since specific ports given.\n");
1419 timid = 0;
1422 if (parport_register_driver (&plip_driver)) {
1423 printk (KERN_WARNING "plip: couldn't register driver\n");
1424 return 1;
1427 return 0;
1430 module_init(plip_init);
1431 module_exit(plip_cleanup_module);
1432 MODULE_LICENSE("GPL");