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