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Merge git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6
[linux-2.6/lfs.git] / drivers / net / plip.c
blob1e965427b0e987faae6ae26bfe3d07e1aad8bfa7
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>
12 *
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.
21 *
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.
28 *
29 * Al Viro
30 * - Changed {enable,disable}_irq handling to make it work
31 * with new ("stack") semantics.
32 *
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.
37 */
38
39 /*
40 * Original version and the name 'PLIP' from Donald Becker <becker@scyld.com>
41 * inspired by Russ Nelson's parallel port packet driver.
42 *
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.
48 *
49 * This version follows original PLIP protocol.
50 * So, this PLIP can't communicate the PLIP of Linux v1.0.
51 */
52
53 /*
54 * To use with DOS box, please do (Turn on ARP switch):
55 * # ifconfig plip[0-2] arp
56 */
57 static const char version[] = "NET3 PLIP version 2.4-parport gniibe@mri.co.jp\n";
58
59 /*
60 Sources:
61 Ideas and protocols came from Russ Nelson's <nelson@crynwr.com>
62 "parallel.asm" parallel port packet driver.
63
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)>
72
73 The packet is encapsulated as if it were ethernet.
74
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
89 */
90
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/if_ether.h>
98 #include <linux/in.h>
99 #include <linux/errno.h>
100 #include <linux/delay.h>
101 #include <linux/init.h>
102 #include <linux/netdevice.h>
103 #include <linux/etherdevice.h>
104 #include <linux/inetdevice.h>
105 #include <linux/skbuff.h>
106 #include <linux/if_plip.h>
107 #include <linux/workqueue.h>
108 #include <linux/spinlock.h>
109 #include <linux/completion.h>
110 #include <linux/parport.h>
111 #include <linux/bitops.h>
112
113 #include <net/neighbour.h>
114
115 #include <asm/system.h>
116 #include <asm/irq.h>
117 #include <asm/byteorder.h>
118
119 /* Maximum number of devices to support. */
120 #define PLIP_MAX 8
121
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;
127
128 #define ENABLE(irq) if (irq != -1) enable_irq(irq)
129 #define DISABLE(irq) if (irq != -1) disable_irq(irq)
130
131 /* In micro second */
132 #define PLIP_DELAY_UNIT 1
133
134 /* Connection time out = PLIP_TRIGGER_WAIT * PLIP_DELAY_UNIT usec */
135 #define PLIP_TRIGGER_WAIT 500
136
137 /* Nibble time out = PLIP_NIBBLE_WAIT * PLIP_DELAY_UNIT usec */
138 #define PLIP_NIBBLE_WAIT 3000
139
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);
144
145 /* Interrupt handler */
146 static void plip_interrupt(void *dev_id);
147
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);
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);
160
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
167 };
168
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
176 };
177
178 enum plip_nibble_state {
179 PLIP_NB_BEGIN,
180 PLIP_NB_1,
181 PLIP_NB_2,
182 };
183
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;
205 };
206
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;
225 };
226
227 static inline void enable_parport_interrupts (struct net_device *dev)
228 {
229 if (dev->irq != -1)
230 {
231 struct parport *port =
232 ((struct net_local *)dev->priv)->pardev->port;
233 port->ops->enable_irq (port);
234 }
235 }
236
237 static inline void disable_parport_interrupts (struct net_device *dev)
238 {
239 if (dev->irq != -1)
240 {
241 struct parport *port =
242 ((struct net_local *)dev->priv)->pardev->port;
243 port->ops->disable_irq (port);
244 }
245 }
246
247 static inline void write_data (struct net_device *dev, unsigned char data)
248 {
249 struct parport *port =
250 ((struct net_local *)dev->priv)->pardev->port;
251
252 port->ops->write_data (port, data);
253 }
254
255 static inline unsigned char read_status (struct net_device *dev)
256 {
257 struct parport *port =
258 ((struct net_local *)dev->priv)->pardev->port;
259
260 return port->ops->read_status (port);
261 }
262
263 static const struct header_ops plip_header_ops = {
264 .create = plip_hard_header,
265 .cache = plip_hard_header_cache,
266 };
267
268 /* Entry point of PLIP driver.
269 Probe the hardware, and register/initialize the driver.
270
271 PLIP is rather weird, because of the way it interacts with the parport
272 system. It is _not_ initialised from Space.c. Instead, plip_init()
273 is called, and that function makes up a "struct net_device" for each port, and
274 then calls us here.
275
276 */
277 static void
278 plip_init_netdev(struct net_device *dev)
279 {
280 struct net_local *nl = netdev_priv(dev);
281
282 /* Then, override parts of it */
283 dev->hard_start_xmit = plip_tx_packet;
284 dev->open = plip_open;
285 dev->stop = plip_close;
286 dev->do_ioctl = plip_ioctl;
287
288 dev->tx_queue_len = 10;
289 dev->flags = IFF_POINTOPOINT|IFF_NOARP;
290 memset(dev->dev_addr, 0xfc, ETH_ALEN);
291
292 dev->header_ops = &plip_header_ops;
293
294
295 nl->port_owner = 0;
296
297 /* Initialize constants */
298 nl->trigger = PLIP_TRIGGER_WAIT;
299 nl->nibble = PLIP_NIBBLE_WAIT;
300
301 /* Initialize task queue structures */
302 INIT_WORK(&nl->immediate, plip_bh);
303 INIT_DELAYED_WORK(&nl->deferred, plip_kick_bh);
304
305 if (dev->irq == -1)
306 INIT_DELAYED_WORK(&nl->timer, plip_timer_bh);
307
308 spin_lock_init(&nl->lock);
309 }
310
311 /* Bottom half handler for the delayed request.
312 This routine is kicked by do_timer().
313 Request `plip_bh' to be invoked. */
314 static void
315 plip_kick_bh(struct work_struct *work)
316 {
317 struct net_local *nl =
318 container_of(work, struct net_local, deferred.work);
319
320 if (nl->is_deferred)
321 schedule_work(&nl->immediate);
322 }
323
324 /* Forward declarations of internal routines */
325 static int plip_none(struct net_device *, struct net_local *,
326 struct plip_local *, struct plip_local *);
327 static int plip_receive_packet(struct net_device *, struct net_local *,
328 struct plip_local *, struct plip_local *);
329 static int plip_send_packet(struct net_device *, struct net_local *,
330 struct plip_local *, struct plip_local *);
331 static int plip_connection_close(struct net_device *, struct net_local *,
332 struct plip_local *, struct plip_local *);
333 static int plip_error(struct net_device *, struct net_local *,
334 struct plip_local *, struct plip_local *);
335 static int plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
336 struct plip_local *snd,
337 struct plip_local *rcv,
338 int error);
339
340 #define OK 0
341 #define TIMEOUT 1
342 #define ERROR 2
343 #define HS_TIMEOUT 3
344
345 typedef int (*plip_func)(struct net_device *dev, struct net_local *nl,
346 struct plip_local *snd, struct plip_local *rcv);
347
348 static const plip_func connection_state_table[] =
349 {
350 plip_none,
351 plip_receive_packet,
352 plip_send_packet,
353 plip_connection_close,
354 plip_error
355 };
356
357 /* Bottom half handler of PLIP. */
358 static void
359 plip_bh(struct work_struct *work)
360 {
361 struct net_local *nl = container_of(work, struct net_local, immediate);
362 struct plip_local *snd = &nl->snd_data;
363 struct plip_local *rcv = &nl->rcv_data;
364 plip_func f;
365 int r;
366
367 nl->is_deferred = 0;
368 f = connection_state_table[nl->connection];
369 if ((r = (*f)(nl->dev, nl, snd, rcv)) != OK
370 && (r = plip_bh_timeout_error(nl->dev, nl, snd, rcv, r)) != OK) {
371 nl->is_deferred = 1;
372 schedule_delayed_work(&nl->deferred, 1);
373 }
374 }
375
376 static void
377 plip_timer_bh(struct work_struct *work)
378 {
379 struct net_local *nl =
380 container_of(work, struct net_local, timer.work);
381
382 if (!(atomic_read (&nl->kill_timer))) {
383 plip_interrupt (nl->dev);
384
385 schedule_delayed_work(&nl->timer, 1);
386 }
387 else {
388 complete(&nl->killed_timer_cmp);
389 }
390 }
391
392 static int
393 plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
394 struct plip_local *snd, struct plip_local *rcv,
395 int error)
396 {
397 unsigned char c0;
398 /*
399 * This is tricky. If we got here from the beginning of send (either
400 * with ERROR or HS_TIMEOUT) we have IRQ enabled. Otherwise it's
401 * already disabled. With the old variant of {enable,disable}_irq()
402 * extra disable_irq() was a no-op. Now it became mortal - it's
403 * unbalanced and thus we'll never re-enable IRQ (until rmmod plip,
404 * that is). So we have to treat HS_TIMEOUT and ERROR from send
405 * in a special way.
406 */
407
408 spin_lock_irq(&nl->lock);
409 if (nl->connection == PLIP_CN_SEND) {
410
411 if (error != ERROR) { /* Timeout */
412 nl->timeout_count++;
413 if ((error == HS_TIMEOUT
414 && nl->timeout_count <= 10)
415 || nl->timeout_count <= 3) {
416 spin_unlock_irq(&nl->lock);
417 /* Try again later */
418 return TIMEOUT;
419 }
420 c0 = read_status(dev);
421 printk(KERN_WARNING "%s: transmit timeout(%d,%02x)\n",
422 dev->name, snd->state, c0);
423 } else
424 error = HS_TIMEOUT;
425 dev->stats.tx_errors++;
426 dev->stats.tx_aborted_errors++;
427 } else if (nl->connection == PLIP_CN_RECEIVE) {
428 if (rcv->state == PLIP_PK_TRIGGER) {
429 /* Transmission was interrupted. */
430 spin_unlock_irq(&nl->lock);
431 return OK;
432 }
433 if (error != ERROR) { /* Timeout */
434 if (++nl->timeout_count <= 3) {
435 spin_unlock_irq(&nl->lock);
436 /* Try again later */
437 return TIMEOUT;
438 }
439 c0 = read_status(dev);
440 printk(KERN_WARNING "%s: receive timeout(%d,%02x)\n",
441 dev->name, rcv->state, c0);
442 }
443 dev->stats.rx_dropped++;
444 }
445 rcv->state = PLIP_PK_DONE;
446 if (rcv->skb) {
447 kfree_skb(rcv->skb);
448 rcv->skb = NULL;
449 }
450 snd->state = PLIP_PK_DONE;
451 if (snd->skb) {
452 dev_kfree_skb(snd->skb);
453 snd->skb = NULL;
454 }
455 spin_unlock_irq(&nl->lock);
456 if (error == HS_TIMEOUT) {
457 DISABLE(dev->irq);
458 synchronize_irq(dev->irq);
459 }
460 disable_parport_interrupts (dev);
461 netif_stop_queue (dev);
462 nl->connection = PLIP_CN_ERROR;
463 write_data (dev, 0x00);
464
465 return TIMEOUT;
466 }
467
468 static int
469 plip_none(struct net_device *dev, struct net_local *nl,
470 struct plip_local *snd, struct plip_local *rcv)
471 {
472 return OK;
473 }
474
475 /* PLIP_RECEIVE --- receive a byte(two nibbles)
476 Returns OK on success, TIMEOUT on timeout */
477 static inline int
478 plip_receive(unsigned short nibble_timeout, struct net_device *dev,
479 enum plip_nibble_state *ns_p, unsigned char *data_p)
480 {
481 unsigned char c0, c1;
482 unsigned int cx;
483
484 switch (*ns_p) {
485 case PLIP_NB_BEGIN:
486 cx = nibble_timeout;
487 while (1) {
488 c0 = read_status(dev);
489 udelay(PLIP_DELAY_UNIT);
490 if ((c0 & 0x80) == 0) {
491 c1 = read_status(dev);
492 if (c0 == c1)
493 break;
494 }
495 if (--cx == 0)
496 return TIMEOUT;
497 }
498 *data_p = (c0 >> 3) & 0x0f;
499 write_data (dev, 0x10); /* send ACK */
500 *ns_p = PLIP_NB_1;
501
502 case PLIP_NB_1:
503 cx = nibble_timeout;
504 while (1) {
505 c0 = read_status(dev);
506 udelay(PLIP_DELAY_UNIT);
507 if (c0 & 0x80) {
508 c1 = read_status(dev);
509 if (c0 == c1)
510 break;
511 }
512 if (--cx == 0)
513 return TIMEOUT;
514 }
515 *data_p |= (c0 << 1) & 0xf0;
516 write_data (dev, 0x00); /* send ACK */
517 *ns_p = PLIP_NB_BEGIN;
518 case PLIP_NB_2:
519 break;
520 }
521 return OK;
522 }
523
524 /*
525 * Determine the packet's protocol ID. The rule here is that we
526 * assume 802.3 if the type field is short enough to be a length.
527 * This is normal practice and works for any 'now in use' protocol.
528 *
529 * PLIP is ethernet ish but the daddr might not be valid if unicast.
530 * PLIP fortunately has no bus architecture (its Point-to-point).
531 *
532 * We can't fix the daddr thing as that quirk (more bug) is embedded
533 * in far too many old systems not all even running Linux.
534 */
535
536 static __be16 plip_type_trans(struct sk_buff *skb, struct net_device *dev)
537 {
538 struct ethhdr *eth;
539 unsigned char *rawp;
540
541 skb_reset_mac_header(skb);
542 skb_pull(skb,dev->hard_header_len);
543 eth = eth_hdr(skb);
544
545 if(*eth->h_dest&1)
546 {
547 if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN)==0)
548 skb->pkt_type=PACKET_BROADCAST;
549 else
550 skb->pkt_type=PACKET_MULTICAST;
551 }
552
553 /*
554 * This ALLMULTI check should be redundant by 1.4
555 * so don't forget to remove it.
556 */
557
558 if (ntohs(eth->h_proto) >= 1536)
559 return eth->h_proto;
560
561 rawp = skb->data;
562
563 /*
564 * This is a magic hack to spot IPX packets. Older Novell breaks
565 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
566 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
567 * won't work for fault tolerant netware but does for the rest.
568 */
569 if (*(unsigned short *)rawp == 0xFFFF)
570 return htons(ETH_P_802_3);
571
572 /*
573 * Real 802.2 LLC
574 */
575 return htons(ETH_P_802_2);
576 }
577
578 /* PLIP_RECEIVE_PACKET --- receive a packet */
579 static int
580 plip_receive_packet(struct net_device *dev, struct net_local *nl,
581 struct plip_local *snd, struct plip_local *rcv)
582 {
583 unsigned short nibble_timeout = nl->nibble;
584 unsigned char *lbuf;
585
586 switch (rcv->state) {
587 case PLIP_PK_TRIGGER:
588 DISABLE(dev->irq);
589 /* Don't need to synchronize irq, as we can safely ignore it */
590 disable_parport_interrupts (dev);
591 write_data (dev, 0x01); /* send ACK */
592 if (net_debug > 2)
593 printk(KERN_DEBUG "%s: receive start\n", dev->name);
594 rcv->state = PLIP_PK_LENGTH_LSB;
595 rcv->nibble = PLIP_NB_BEGIN;
596
597 case PLIP_PK_LENGTH_LSB:
598 if (snd->state != PLIP_PK_DONE) {
599 if (plip_receive(nl->trigger, dev,
600 &rcv->nibble, &rcv->length.b.lsb)) {
601 /* collision, here dev->tbusy == 1 */
602 rcv->state = PLIP_PK_DONE;
603 nl->is_deferred = 1;
604 nl->connection = PLIP_CN_SEND;
605 schedule_delayed_work(&nl->deferred, 1);
606 enable_parport_interrupts (dev);
607 ENABLE(dev->irq);
608 return OK;
609 }
610 } else {
611 if (plip_receive(nibble_timeout, dev,
612 &rcv->nibble, &rcv->length.b.lsb))
613 return TIMEOUT;
614 }
615 rcv->state = PLIP_PK_LENGTH_MSB;
616
617 case PLIP_PK_LENGTH_MSB:
618 if (plip_receive(nibble_timeout, dev,
619 &rcv->nibble, &rcv->length.b.msb))
620 return TIMEOUT;
621 if (rcv->length.h > dev->mtu + dev->hard_header_len
622 || rcv->length.h < 8) {
623 printk(KERN_WARNING "%s: bogus packet size %d.\n", dev->name, rcv->length.h);
624 return ERROR;
625 }
626 /* Malloc up new buffer. */
627 rcv->skb = dev_alloc_skb(rcv->length.h + 2);
628 if (rcv->skb == NULL) {
629 printk(KERN_ERR "%s: Memory squeeze.\n", dev->name);
630 return ERROR;
631 }
632 skb_reserve(rcv->skb, 2); /* Align IP on 16 byte boundaries */
633 skb_put(rcv->skb,rcv->length.h);
634 rcv->skb->dev = dev;
635 rcv->state = PLIP_PK_DATA;
636 rcv->byte = 0;
637 rcv->checksum = 0;
638
639 case PLIP_PK_DATA:
640 lbuf = rcv->skb->data;
641 do
642 if (plip_receive(nibble_timeout, dev,
643 &rcv->nibble, &lbuf[rcv->byte]))
644 return TIMEOUT;
645 while (++rcv->byte < rcv->length.h);
646 do
647 rcv->checksum += lbuf[--rcv->byte];
648 while (rcv->byte);
649 rcv->state = PLIP_PK_CHECKSUM;
650
651 case PLIP_PK_CHECKSUM:
652 if (plip_receive(nibble_timeout, dev,
653 &rcv->nibble, &rcv->data))
654 return TIMEOUT;
655 if (rcv->data != rcv->checksum) {
656 dev->stats.rx_crc_errors++;
657 if (net_debug)
658 printk(KERN_DEBUG "%s: checksum error\n", dev->name);
659 return ERROR;
660 }
661 rcv->state = PLIP_PK_DONE;
662
663 case PLIP_PK_DONE:
664 /* Inform the upper layer for the arrival of a packet. */
665 rcv->skb->protocol=plip_type_trans(rcv->skb, dev);
666 netif_rx_ni(rcv->skb);
667 dev->last_rx = jiffies;
668 dev->stats.rx_bytes += rcv->length.h;
669 dev->stats.rx_packets++;
670 rcv->skb = NULL;
671 if (net_debug > 2)
672 printk(KERN_DEBUG "%s: receive end\n", dev->name);
673
674 /* Close the connection. */
675 write_data (dev, 0x00);
676 spin_lock_irq(&nl->lock);
677 if (snd->state != PLIP_PK_DONE) {
678 nl->connection = PLIP_CN_SEND;
679 spin_unlock_irq(&nl->lock);
680 schedule_work(&nl->immediate);
681 enable_parport_interrupts (dev);
682 ENABLE(dev->irq);
683 return OK;
684 } else {
685 nl->connection = PLIP_CN_NONE;
686 spin_unlock_irq(&nl->lock);
687 enable_parport_interrupts (dev);
688 ENABLE(dev->irq);
689 return OK;
690 }
691 }
692 return OK;
693 }
694
695 /* PLIP_SEND --- send a byte (two nibbles)
696 Returns OK on success, TIMEOUT when timeout */
697 static inline int
698 plip_send(unsigned short nibble_timeout, struct net_device *dev,
699 enum plip_nibble_state *ns_p, unsigned char data)
700 {
701 unsigned char c0;
702 unsigned int cx;
703
704 switch (*ns_p) {
705 case PLIP_NB_BEGIN:
706 write_data (dev, data & 0x0f);
707 *ns_p = PLIP_NB_1;
708
709 case PLIP_NB_1:
710 write_data (dev, 0x10 | (data & 0x0f));
711 cx = nibble_timeout;
712 while (1) {
713 c0 = read_status(dev);
714 if ((c0 & 0x80) == 0)
715 break;
716 if (--cx == 0)
717 return TIMEOUT;
718 udelay(PLIP_DELAY_UNIT);
719 }
720 write_data (dev, 0x10 | (data >> 4));
721 *ns_p = PLIP_NB_2;
722
723 case PLIP_NB_2:
724 write_data (dev, (data >> 4));
725 cx = nibble_timeout;
726 while (1) {
727 c0 = read_status(dev);
728 if (c0 & 0x80)
729 break;
730 if (--cx == 0)
731 return TIMEOUT;
732 udelay(PLIP_DELAY_UNIT);
733 }
734 *ns_p = PLIP_NB_BEGIN;
735 return OK;
736 }
737 return OK;
738 }
739
740 /* PLIP_SEND_PACKET --- send a packet */
741 static int
742 plip_send_packet(struct net_device *dev, struct net_local *nl,
743 struct plip_local *snd, struct plip_local *rcv)
744 {
745 unsigned short nibble_timeout = nl->nibble;
746 unsigned char *lbuf;
747 unsigned char c0;
748 unsigned int cx;
749
750 if (snd->skb == NULL || (lbuf = snd->skb->data) == NULL) {
751 printk(KERN_DEBUG "%s: send skb lost\n", dev->name);
752 snd->state = PLIP_PK_DONE;
753 snd->skb = NULL;
754 return ERROR;
755 }
756
757 switch (snd->state) {
758 case PLIP_PK_TRIGGER:
759 if ((read_status(dev) & 0xf8) != 0x80)
760 return HS_TIMEOUT;
761
762 /* Trigger remote rx interrupt. */
763 write_data (dev, 0x08);
764 cx = nl->trigger;
765 while (1) {
766 udelay(PLIP_DELAY_UNIT);
767 spin_lock_irq(&nl->lock);
768 if (nl->connection == PLIP_CN_RECEIVE) {
769 spin_unlock_irq(&nl->lock);
770 /* Interrupted. */
771 dev->stats.collisions++;
772 return OK;
773 }
774 c0 = read_status(dev);
775 if (c0 & 0x08) {
776 spin_unlock_irq(&nl->lock);
777 DISABLE(dev->irq);
778 synchronize_irq(dev->irq);
779 if (nl->connection == PLIP_CN_RECEIVE) {
780 /* Interrupted.
781 We don't need to enable irq,
782 as it is soon disabled. */
783 /* Yes, we do. New variant of
784 {enable,disable}_irq *counts*
785 them. -- AV */
786 ENABLE(dev->irq);
787 dev->stats.collisions++;
788 return OK;
789 }
790 disable_parport_interrupts (dev);
791 if (net_debug > 2)
792 printk(KERN_DEBUG "%s: send start\n", dev->name);
793 snd->state = PLIP_PK_LENGTH_LSB;
794 snd->nibble = PLIP_NB_BEGIN;
795 nl->timeout_count = 0;
796 break;
797 }
798 spin_unlock_irq(&nl->lock);
799 if (--cx == 0) {
800 write_data (dev, 0x00);
801 return HS_TIMEOUT;
802 }
803 }
804
805 case PLIP_PK_LENGTH_LSB:
806 if (plip_send(nibble_timeout, dev,
807 &snd->nibble, snd->length.b.lsb))
808 return TIMEOUT;
809 snd->state = PLIP_PK_LENGTH_MSB;
810
811 case PLIP_PK_LENGTH_MSB:
812 if (plip_send(nibble_timeout, dev,
813 &snd->nibble, snd->length.b.msb))
814 return TIMEOUT;
815 snd->state = PLIP_PK_DATA;
816 snd->byte = 0;
817 snd->checksum = 0;
818
819 case PLIP_PK_DATA:
820 do
821 if (plip_send(nibble_timeout, dev,
822 &snd->nibble, lbuf[snd->byte]))
823 return TIMEOUT;
824 while (++snd->byte < snd->length.h);
825 do
826 snd->checksum += lbuf[--snd->byte];
827 while (snd->byte);
828 snd->state = PLIP_PK_CHECKSUM;
829
830 case PLIP_PK_CHECKSUM:
831 if (plip_send(nibble_timeout, dev,
832 &snd->nibble, snd->checksum))
833 return TIMEOUT;
834
835 dev->stats.tx_bytes += snd->skb->len;
836 dev_kfree_skb(snd->skb);
837 dev->stats.tx_packets++;
838 snd->state = PLIP_PK_DONE;
839
840 case PLIP_PK_DONE:
841 /* Close the connection */
842 write_data (dev, 0x00);
843 snd->skb = NULL;
844 if (net_debug > 2)
845 printk(KERN_DEBUG "%s: send end\n", dev->name);
846 nl->connection = PLIP_CN_CLOSING;
847 nl->is_deferred = 1;
848 schedule_delayed_work(&nl->deferred, 1);
849 enable_parport_interrupts (dev);
850 ENABLE(dev->irq);
851 return OK;
852 }
853 return OK;
854 }
855
856 static int
857 plip_connection_close(struct net_device *dev, struct net_local *nl,
858 struct plip_local *snd, struct plip_local *rcv)
859 {
860 spin_lock_irq(&nl->lock);
861 if (nl->connection == PLIP_CN_CLOSING) {
862 nl->connection = PLIP_CN_NONE;
863 netif_wake_queue (dev);
864 }
865 spin_unlock_irq(&nl->lock);
866 if (nl->should_relinquish) {
867 nl->should_relinquish = nl->port_owner = 0;
868 parport_release(nl->pardev);
869 }
870 return OK;
871 }
872
873 /* PLIP_ERROR --- wait till other end settled */
874 static int
875 plip_error(struct net_device *dev, struct net_local *nl,
876 struct plip_local *snd, struct plip_local *rcv)
877 {
878 unsigned char status;
879
880 status = read_status(dev);
881 if ((status & 0xf8) == 0x80) {
882 if (net_debug > 2)
883 printk(KERN_DEBUG "%s: reset interface.\n", dev->name);
884 nl->connection = PLIP_CN_NONE;
885 nl->should_relinquish = 0;
886 netif_start_queue (dev);
887 enable_parport_interrupts (dev);
888 ENABLE(dev->irq);
889 netif_wake_queue (dev);
890 } else {
891 nl->is_deferred = 1;
892 schedule_delayed_work(&nl->deferred, 1);
893 }
894
895 return OK;
896 }
897
898 /* Handle the parallel port interrupts. */
899 static void
900 plip_interrupt(void *dev_id)
901 {
902 struct net_device *dev = dev_id;
903 struct net_local *nl;
904 struct plip_local *rcv;
905 unsigned char c0;
906 unsigned long flags;
907
908 nl = netdev_priv(dev);
909 rcv = &nl->rcv_data;
910
911 spin_lock_irqsave (&nl->lock, flags);
912
913 c0 = read_status(dev);
914 if ((c0 & 0xf8) != 0xc0) {
915 if ((dev->irq != -1) && (net_debug > 1))
916 printk(KERN_DEBUG "%s: spurious interrupt\n", dev->name);
917 spin_unlock_irqrestore (&nl->lock, flags);
918 return;
919 }
920
921 if (net_debug > 3)
922 printk(KERN_DEBUG "%s: interrupt.\n", dev->name);
923
924 switch (nl->connection) {
925 case PLIP_CN_CLOSING:
926 netif_wake_queue (dev);
927 case PLIP_CN_NONE:
928 case PLIP_CN_SEND:
929 rcv->state = PLIP_PK_TRIGGER;
930 nl->connection = PLIP_CN_RECEIVE;
931 nl->timeout_count = 0;
932 schedule_work(&nl->immediate);
933 break;
934
935 case PLIP_CN_RECEIVE:
936 /* May occur because there is race condition
937 around test and set of dev->interrupt.
938 Ignore this interrupt. */
939 break;
940
941 case PLIP_CN_ERROR:
942 printk(KERN_ERR "%s: receive interrupt in error state\n", dev->name);
943 break;
944 }
945
946 spin_unlock_irqrestore(&nl->lock, flags);
947 }
948
949 static int
950 plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
951 {
952 struct net_local *nl = netdev_priv(dev);
953 struct plip_local *snd = &nl->snd_data;
954
955 if (netif_queue_stopped(dev))
956 return 1;
957
958 /* We may need to grab the bus */
959 if (!nl->port_owner) {
960 if (parport_claim(nl->pardev))
961 return 1;
962 nl->port_owner = 1;
963 }
964
965 netif_stop_queue (dev);
966
967 if (skb->len > dev->mtu + dev->hard_header_len) {
968 printk(KERN_WARNING "%s: packet too big, %d.\n", dev->name, (int)skb->len);
969 netif_start_queue (dev);
970 return 1;
971 }
972
973 if (net_debug > 2)
974 printk(KERN_DEBUG "%s: send request\n", dev->name);
975
976 spin_lock_irq(&nl->lock);
977 dev->trans_start = jiffies;
978 snd->skb = skb;
979 snd->length.h = skb->len;
980 snd->state = PLIP_PK_TRIGGER;
981 if (nl->connection == PLIP_CN_NONE) {
982 nl->connection = PLIP_CN_SEND;
983 nl->timeout_count = 0;
984 }
985 schedule_work(&nl->immediate);
986 spin_unlock_irq(&nl->lock);
987
988 return 0;
989 }
990
991 static void
992 plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
993 {
994 const struct in_device *in_dev = dev->ip_ptr;
995
996 if (in_dev) {
997 /* Any address will do - we take the first */
998 const struct in_ifaddr *ifa = in_dev->ifa_list;
999 if (ifa) {
1000 memcpy(eth->h_source, dev->dev_addr, 6);
1001 memset(eth->h_dest, 0xfc, 2);
1002 memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
1003 }
1004 }
1005 }
1006
1007 static int
1008 plip_hard_header(struct sk_buff *skb, struct net_device *dev,
1009 unsigned short type, const void *daddr,
1010 const void *saddr, unsigned len)
1011 {
1012 int ret;
1013
1014 ret = eth_header(skb, dev, type, daddr, saddr, len);
1015 if (ret >= 0)
1016 plip_rewrite_address (dev, (struct ethhdr *)skb->data);
1017
1018 return ret;
1019 }
1020
1021 int plip_hard_header_cache(const struct neighbour *neigh,
1022 struct hh_cache *hh)
1023 {
1024 int ret;
1025
1026 ret = eth_header_cache(neigh, hh);
1027 if (ret == 0) {
1028 struct ethhdr *eth;
1029
1030 eth = (struct ethhdr*)(((u8*)hh->hh_data) +
1031 HH_DATA_OFF(sizeof(*eth)));
1032 plip_rewrite_address (neigh->dev, eth);
1033 }
1034
1035 return ret;
1036 }
1037
1038 /* Open/initialize the board. This is called (in the current kernel)
1039 sometime after booting when the 'ifconfig' program is run.
1040
1041 This routine gets exclusive access to the parallel port by allocating
1042 its IRQ line.
1043 */
1044 static int
1045 plip_open(struct net_device *dev)
1046 {
1047 struct net_local *nl = netdev_priv(dev);
1048 struct in_device *in_dev;
1049
1050 /* Grab the port */
1051 if (!nl->port_owner) {
1052 if (parport_claim(nl->pardev)) return -EAGAIN;
1053 nl->port_owner = 1;
1054 }
1055
1056 nl->should_relinquish = 0;
1057
1058 /* Clear the data port. */
1059 write_data (dev, 0x00);
1060
1061 /* Enable rx interrupt. */
1062 enable_parport_interrupts (dev);
1063 if (dev->irq == -1)
1064 {
1065 atomic_set (&nl->kill_timer, 0);
1066 schedule_delayed_work(&nl->timer, 1);
1067 }
1068
1069 /* Initialize the state machine. */
1070 nl->rcv_data.state = nl->snd_data.state = PLIP_PK_DONE;
1071 nl->rcv_data.skb = nl->snd_data.skb = NULL;
1072 nl->connection = PLIP_CN_NONE;
1073 nl->is_deferred = 0;
1074
1075 /* Fill in the MAC-level header.
1076 We used to abuse dev->broadcast to store the point-to-point
1077 MAC address, but we no longer do it. Instead, we fetch the
1078 interface address whenever it is needed, which is cheap enough
1079 because we use the hh_cache. Actually, abusing dev->broadcast
1080 didn't work, because when using plip_open the point-to-point
1081 address isn't yet known.
1082 PLIP doesn't have a real MAC address, but we need it to be
1083 DOS compatible, and to properly support taps (otherwise,
1084 when the device address isn't identical to the address of a
1085 received frame, the kernel incorrectly drops it). */
1086
1087 if ((in_dev=dev->ip_ptr) != NULL) {
1088 /* Any address will do - we take the first. We already
1089 have the first two bytes filled with 0xfc, from
1090 plip_init_dev(). */
1091 struct in_ifaddr *ifa=in_dev->ifa_list;
1092 if (ifa != NULL) {
1093 memcpy(dev->dev_addr+2, &ifa->ifa_local, 4);
1094 }
1095 }
1096
1097 netif_start_queue (dev);
1098
1099 return 0;
1100 }
1101
1102 /* The inverse routine to plip_open (). */
1103 static int
1104 plip_close(struct net_device *dev)
1105 {
1106 struct net_local *nl = netdev_priv(dev);
1107 struct plip_local *snd = &nl->snd_data;
1108 struct plip_local *rcv = &nl->rcv_data;
1109
1110 netif_stop_queue (dev);
1111 DISABLE(dev->irq);
1112 synchronize_irq(dev->irq);
1113
1114 if (dev->irq == -1)
1115 {
1116 init_completion(&nl->killed_timer_cmp);
1117 atomic_set (&nl->kill_timer, 1);
1118 wait_for_completion(&nl->killed_timer_cmp);
1119 }
1120
1121 #ifdef NOTDEF
1122 outb(0x00, PAR_DATA(dev));
1123 #endif
1124 nl->is_deferred = 0;
1125 nl->connection = PLIP_CN_NONE;
1126 if (nl->port_owner) {
1127 parport_release(nl->pardev);
1128 nl->port_owner = 0;
1129 }
1130
1131 snd->state = PLIP_PK_DONE;
1132 if (snd->skb) {
1133 dev_kfree_skb(snd->skb);
1134 snd->skb = NULL;
1135 }
1136 rcv->state = PLIP_PK_DONE;
1137 if (rcv->skb) {
1138 kfree_skb(rcv->skb);
1139 rcv->skb = NULL;
1140 }
1141
1142 #ifdef NOTDEF
1143 /* Reset. */
1144 outb(0x00, PAR_CONTROL(dev));
1145 #endif
1146 return 0;
1147 }
1148
1149 static int
1150 plip_preempt(void *handle)
1151 {
1152 struct net_device *dev = (struct net_device *)handle;
1153 struct net_local *nl = netdev_priv(dev);
1154
1155 /* Stand our ground if a datagram is on the wire */
1156 if (nl->connection != PLIP_CN_NONE) {
1157 nl->should_relinquish = 1;
1158 return 1;
1159 }
1160
1161 nl->port_owner = 0; /* Remember that we released the bus */
1162 return 0;
1163 }
1164
1165 static void
1166 plip_wakeup(void *handle)
1167 {
1168 struct net_device *dev = (struct net_device *)handle;
1169 struct net_local *nl = netdev_priv(dev);
1170
1171 if (nl->port_owner) {
1172 /* Why are we being woken up? */
1173 printk(KERN_DEBUG "%s: why am I being woken up?\n", dev->name);
1174 if (!parport_claim(nl->pardev))
1175 /* bus_owner is already set (but why?) */
1176 printk(KERN_DEBUG "%s: I'm broken.\n", dev->name);
1177 else
1178 return;
1179 }
1180
1181 if (!(dev->flags & IFF_UP))
1182 /* Don't need the port when the interface is down */
1183 return;
1184
1185 if (!parport_claim(nl->pardev)) {
1186 nl->port_owner = 1;
1187 /* Clear the data port. */
1188 write_data (dev, 0x00);
1189 }
1190
1191 return;
1192 }
1193
1194 static int
1195 plip_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1196 {
1197 struct net_local *nl = netdev_priv(dev);
1198 struct plipconf *pc = (struct plipconf *) &rq->ifr_ifru;
1199
1200 if (cmd != SIOCDEVPLIP)
1201 return -EOPNOTSUPP;
1202
1203 switch(pc->pcmd) {
1204 case PLIP_GET_TIMEOUT:
1205 pc->trigger = nl->trigger;
1206 pc->nibble = nl->nibble;
1207 break;
1208 case PLIP_SET_TIMEOUT:
1209 if(!capable(CAP_NET_ADMIN))
1210 return -EPERM;
1211 nl->trigger = pc->trigger;
1212 nl->nibble = pc->nibble;
1213 break;
1214 default:
1215 return -EOPNOTSUPP;
1216 }
1217 return 0;
1218 }
1219
1220 static int parport[PLIP_MAX] = { [0 ... PLIP_MAX-1] = -1 };
1221 static int timid;
1222
1223 module_param_array(parport, int, NULL, 0);
1224 module_param(timid, int, 0);
1225 MODULE_PARM_DESC(parport, "List of parport device numbers to use by plip");
1226
1227 static struct net_device *dev_plip[PLIP_MAX] = { NULL, };
1228
1229 static inline int
1230 plip_searchfor(int list[], int a)
1231 {
1232 int i;
1233 for (i = 0; i < PLIP_MAX && list[i] != -1; i++) {
1234 if (list[i] == a) return 1;
1235 }
1236 return 0;
1237 }
1238
1239 /* plip_attach() is called (by the parport code) when a port is
1240 * available to use. */
1241 static void plip_attach (struct parport *port)
1242 {
1243 static int unit;
1244 struct net_device *dev;
1245 struct net_local *nl;
1246 char name[IFNAMSIZ];
1247
1248 if ((parport[0] == -1 && (!timid || !port->devices)) ||
1249 plip_searchfor(parport, port->number)) {
1250 if (unit == PLIP_MAX) {
1251 printk(KERN_ERR "plip: too many devices\n");
1252 return;
1253 }
1254
1255 sprintf(name, "plip%d", unit);
1256 dev = alloc_etherdev(sizeof(struct net_local));
1257 if (!dev) {
1258 printk(KERN_ERR "plip: memory squeeze\n");
1259 return;
1260 }
1261
1262 strcpy(dev->name, name);
1263
1264 dev->irq = port->irq;
1265 dev->base_addr = port->base;
1266 if (port->irq == -1) {
1267 printk(KERN_INFO "plip: %s has no IRQ. Using IRQ-less mode,"
1268 "which is fairly inefficient!\n", port->name);
1269 }
1270
1271 nl = netdev_priv(dev);
1272 nl->dev = dev;
1273 nl->pardev = parport_register_device(port, dev->name, plip_preempt,
1274 plip_wakeup, plip_interrupt,
1275 0, dev);
1276
1277 if (!nl->pardev) {
1278 printk(KERN_ERR "%s: parport_register failed\n", name);
1279 goto err_free_dev;
1280 return;
1281 }
1282
1283 plip_init_netdev(dev);
1284
1285 if (register_netdev(dev)) {
1286 printk(KERN_ERR "%s: network register failed\n", name);
1287 goto err_parport_unregister;
1288 }
1289
1290 printk(KERN_INFO "%s", version);
1291 if (dev->irq != -1)
1292 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1293 "using IRQ %d.\n",
1294 dev->name, dev->base_addr, dev->irq);
1295 else
1296 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1297 "not using IRQ.\n",
1298 dev->name, dev->base_addr);
1299 dev_plip[unit++] = dev;
1300 }
1301 return;
1302
1303 err_parport_unregister:
1304 parport_unregister_device(nl->pardev);
1305 err_free_dev:
1306 free_netdev(dev);
1307 return;
1308 }
1309
1310 /* plip_detach() is called (by the parport code) when a port is
1311 * no longer available to use. */
1312 static void plip_detach (struct parport *port)
1313 {
1314 /* Nothing to do */
1315 }
1316
1317 static struct parport_driver plip_driver = {
1318 .name = "plip",
1319 .attach = plip_attach,
1320 .detach = plip_detach
1321 };
1322
1323 static void __exit plip_cleanup_module (void)
1324 {
1325 struct net_device *dev;
1326 int i;
1327
1328 parport_unregister_driver (&plip_driver);
1329
1330 for (i=0; i < PLIP_MAX; i++) {
1331 if ((dev = dev_plip[i])) {
1332 struct net_local *nl = netdev_priv(dev);
1333 unregister_netdev(dev);
1334 if (nl->port_owner)
1335 parport_release(nl->pardev);
1336 parport_unregister_device(nl->pardev);
1337 free_netdev(dev);
1338 dev_plip[i] = NULL;
1339 }
1340 }
1341 }
1342
1343 #ifndef MODULE
1344
1345 static int parport_ptr;
1346
1347 static int __init plip_setup(char *str)
1348 {
1349 int ints[4];
1350
1351 str = get_options(str, ARRAY_SIZE(ints), ints);
1352
1353 /* Ugh. */
1354 if (!strncmp(str, "parport", 7)) {
1355 int n = simple_strtoul(str+7, NULL, 10);
1356 if (parport_ptr < PLIP_MAX)
1357 parport[parport_ptr++] = n;
1358 else
1359 printk(KERN_INFO "plip: too many ports, %s ignored.\n",
1360 str);
1361 } else if (!strcmp(str, "timid")) {
1362 timid = 1;
1363 } else {
1364 if (ints[0] == 0 || ints[1] == 0) {
1365 /* disable driver on "plip=" or "plip=0" */
1366 parport[0] = -2;
1367 } else {
1368 printk(KERN_WARNING "warning: 'plip=0x%x' ignored\n",
1369 ints[1]);
1370 }
1371 }
1372 return 1;
1373 }
1374
1375 __setup("plip=", plip_setup);
1376
1377 #endif /* !MODULE */
1378
1379 static int __init plip_init (void)
1380 {
1381 if (parport[0] == -2)
1382 return 0;
1383
1384 if (parport[0] != -1 && timid) {
1385 printk(KERN_WARNING "plip: warning, ignoring `timid' since specific ports given.\n");
1386 timid = 0;
1387 }
1388
1389 if (parport_register_driver (&plip_driver)) {
1390 printk (KERN_WARNING "plip: couldn't register driver\n");
1391 return 1;
1392 }
1393
1394 return 0;
1395 }
1396
1397 module_init(plip_init);
1398 module_exit(plip_cleanup_module);
1399 MODULE_LICENSE("GPL");
1400
1401 /*
1402 * Local variables:
1403 * compile-command: "gcc -DMODULE -DMODVERSIONS -D__KERNEL__ -Wall -Wstrict-prototypes -O2 -g -fomit-frame-pointer -pipe -c plip.c"
1404 * End:
1405 */
Log-structured file system for Linux