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Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[linux-2.6/mini2440.git] / drivers / net / plip.c
blob0be0f0b164f3cf6833701ecbf26369293d07fe3e
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 };
274
275 /* Entry point of PLIP driver.
276 Probe the hardware, and register/initialize the driver.
277
278 PLIP is rather weird, because of the way it interacts with the parport
279 system. It is _not_ initialised from Space.c. Instead, plip_init()
280 is called, and that function makes up a "struct net_device" for each port, and
281 then calls us here.
282
283 */
284 static void
285 plip_init_netdev(struct net_device *dev)
286 {
287 struct net_local *nl = netdev_priv(dev);
288
289 /* Then, override parts of it */
290 dev->tx_queue_len = 10;
291 dev->flags = IFF_POINTOPOINT|IFF_NOARP;
292 memset(dev->dev_addr, 0xfc, ETH_ALEN);
293
294 dev->netdev_ops = &plip_netdev_ops;
295 dev->header_ops = &plip_header_ops;
296
297
298 nl->port_owner = 0;
299
300 /* Initialize constants */
301 nl->trigger = PLIP_TRIGGER_WAIT;
302 nl->nibble = PLIP_NIBBLE_WAIT;
303
304 /* Initialize task queue structures */
305 INIT_WORK(&nl->immediate, plip_bh);
306 INIT_DELAYED_WORK(&nl->deferred, plip_kick_bh);
307
308 if (dev->irq == -1)
309 INIT_DELAYED_WORK(&nl->timer, plip_timer_bh);
310
311 spin_lock_init(&nl->lock);
312 }
313
314 /* Bottom half handler for the delayed request.
315 This routine is kicked by do_timer().
316 Request `plip_bh' to be invoked. */
317 static void
318 plip_kick_bh(struct work_struct *work)
319 {
320 struct net_local *nl =
321 container_of(work, struct net_local, deferred.work);
322
323 if (nl->is_deferred)
324 schedule_work(&nl->immediate);
325 }
326
327 /* Forward declarations of internal routines */
328 static int plip_none(struct net_device *, struct net_local *,
329 struct plip_local *, struct plip_local *);
330 static int plip_receive_packet(struct net_device *, struct net_local *,
331 struct plip_local *, struct plip_local *);
332 static int plip_send_packet(struct net_device *, struct net_local *,
333 struct plip_local *, struct plip_local *);
334 static int plip_connection_close(struct net_device *, struct net_local *,
335 struct plip_local *, struct plip_local *);
336 static int plip_error(struct net_device *, struct net_local *,
337 struct plip_local *, struct plip_local *);
338 static int plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
339 struct plip_local *snd,
340 struct plip_local *rcv,
341 int error);
342
343 #define OK 0
344 #define TIMEOUT 1
345 #define ERROR 2
346 #define HS_TIMEOUT 3
347
348 typedef int (*plip_func)(struct net_device *dev, struct net_local *nl,
349 struct plip_local *snd, struct plip_local *rcv);
350
351 static const plip_func connection_state_table[] =
352 {
353 plip_none,
354 plip_receive_packet,
355 plip_send_packet,
356 plip_connection_close,
357 plip_error
358 };
359
360 /* Bottom half handler of PLIP. */
361 static void
362 plip_bh(struct work_struct *work)
363 {
364 struct net_local *nl = container_of(work, struct net_local, immediate);
365 struct plip_local *snd = &nl->snd_data;
366 struct plip_local *rcv = &nl->rcv_data;
367 plip_func f;
368 int r;
369
370 nl->is_deferred = 0;
371 f = connection_state_table[nl->connection];
372 if ((r = (*f)(nl->dev, nl, snd, rcv)) != OK
373 && (r = plip_bh_timeout_error(nl->dev, nl, snd, rcv, r)) != OK) {
374 nl->is_deferred = 1;
375 schedule_delayed_work(&nl->deferred, 1);
376 }
377 }
378
379 static void
380 plip_timer_bh(struct work_struct *work)
381 {
382 struct net_local *nl =
383 container_of(work, struct net_local, timer.work);
384
385 if (!(atomic_read (&nl->kill_timer))) {
386 plip_interrupt (nl->dev);
387
388 schedule_delayed_work(&nl->timer, 1);
389 }
390 else {
391 complete(&nl->killed_timer_cmp);
392 }
393 }
394
395 static int
396 plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
397 struct plip_local *snd, struct plip_local *rcv,
398 int error)
399 {
400 unsigned char c0;
401 /*
402 * This is tricky. If we got here from the beginning of send (either
403 * with ERROR or HS_TIMEOUT) we have IRQ enabled. Otherwise it's
404 * already disabled. With the old variant of {enable,disable}_irq()
405 * extra disable_irq() was a no-op. Now it became mortal - it's
406 * unbalanced and thus we'll never re-enable IRQ (until rmmod plip,
407 * that is). So we have to treat HS_TIMEOUT and ERROR from send
408 * in a special way.
409 */
410
411 spin_lock_irq(&nl->lock);
412 if (nl->connection == PLIP_CN_SEND) {
413
414 if (error != ERROR) { /* Timeout */
415 nl->timeout_count++;
416 if ((error == HS_TIMEOUT
417 && nl->timeout_count <= 10)
418 || nl->timeout_count <= 3) {
419 spin_unlock_irq(&nl->lock);
420 /* Try again later */
421 return TIMEOUT;
422 }
423 c0 = read_status(dev);
424 printk(KERN_WARNING "%s: transmit timeout(%d,%02x)\n",
425 dev->name, snd->state, c0);
426 } else
427 error = HS_TIMEOUT;
428 dev->stats.tx_errors++;
429 dev->stats.tx_aborted_errors++;
430 } else if (nl->connection == PLIP_CN_RECEIVE) {
431 if (rcv->state == PLIP_PK_TRIGGER) {
432 /* Transmission was interrupted. */
433 spin_unlock_irq(&nl->lock);
434 return OK;
435 }
436 if (error != ERROR) { /* Timeout */
437 if (++nl->timeout_count <= 3) {
438 spin_unlock_irq(&nl->lock);
439 /* Try again later */
440 return TIMEOUT;
441 }
442 c0 = read_status(dev);
443 printk(KERN_WARNING "%s: receive timeout(%d,%02x)\n",
444 dev->name, rcv->state, c0);
445 }
446 dev->stats.rx_dropped++;
447 }
448 rcv->state = PLIP_PK_DONE;
449 if (rcv->skb) {
450 kfree_skb(rcv->skb);
451 rcv->skb = NULL;
452 }
453 snd->state = PLIP_PK_DONE;
454 if (snd->skb) {
455 dev_kfree_skb(snd->skb);
456 snd->skb = NULL;
457 }
458 spin_unlock_irq(&nl->lock);
459 if (error == HS_TIMEOUT) {
460 DISABLE(dev->irq);
461 synchronize_irq(dev->irq);
462 }
463 disable_parport_interrupts (dev);
464 netif_stop_queue (dev);
465 nl->connection = PLIP_CN_ERROR;
466 write_data (dev, 0x00);
467
468 return TIMEOUT;
469 }
470
471 static int
472 plip_none(struct net_device *dev, struct net_local *nl,
473 struct plip_local *snd, struct plip_local *rcv)
474 {
475 return OK;
476 }
477
478 /* PLIP_RECEIVE --- receive a byte(two nibbles)
479 Returns OK on success, TIMEOUT on timeout */
480 static inline int
481 plip_receive(unsigned short nibble_timeout, struct net_device *dev,
482 enum plip_nibble_state *ns_p, unsigned char *data_p)
483 {
484 unsigned char c0, c1;
485 unsigned int cx;
486
487 switch (*ns_p) {
488 case PLIP_NB_BEGIN:
489 cx = nibble_timeout;
490 while (1) {
491 c0 = read_status(dev);
492 udelay(PLIP_DELAY_UNIT);
493 if ((c0 & 0x80) == 0) {
494 c1 = read_status(dev);
495 if (c0 == c1)
496 break;
497 }
498 if (--cx == 0)
499 return TIMEOUT;
500 }
501 *data_p = (c0 >> 3) & 0x0f;
502 write_data (dev, 0x10); /* send ACK */
503 *ns_p = PLIP_NB_1;
504
505 case PLIP_NB_1:
506 cx = nibble_timeout;
507 while (1) {
508 c0 = read_status(dev);
509 udelay(PLIP_DELAY_UNIT);
510 if (c0 & 0x80) {
511 c1 = read_status(dev);
512 if (c0 == c1)
513 break;
514 }
515 if (--cx == 0)
516 return TIMEOUT;
517 }
518 *data_p |= (c0 << 1) & 0xf0;
519 write_data (dev, 0x00); /* send ACK */
520 *ns_p = PLIP_NB_BEGIN;
521 case PLIP_NB_2:
522 break;
523 }
524 return OK;
525 }
526
527 /*
528 * Determine the packet's protocol ID. The rule here is that we
529 * assume 802.3 if the type field is short enough to be a length.
530 * This is normal practice and works for any 'now in use' protocol.
531 *
532 * PLIP is ethernet ish but the daddr might not be valid if unicast.
533 * PLIP fortunately has no bus architecture (its Point-to-point).
534 *
535 * We can't fix the daddr thing as that quirk (more bug) is embedded
536 * in far too many old systems not all even running Linux.
537 */
538
539 static __be16 plip_type_trans(struct sk_buff *skb, struct net_device *dev)
540 {
541 struct ethhdr *eth;
542 unsigned char *rawp;
543
544 skb_reset_mac_header(skb);
545 skb_pull(skb,dev->hard_header_len);
546 eth = eth_hdr(skb);
547
548 if(*eth->h_dest&1)
549 {
550 if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN)==0)
551 skb->pkt_type=PACKET_BROADCAST;
552 else
553 skb->pkt_type=PACKET_MULTICAST;
554 }
555
556 /*
557 * This ALLMULTI check should be redundant by 1.4
558 * so don't forget to remove it.
559 */
560
561 if (ntohs(eth->h_proto) >= 1536)
562 return eth->h_proto;
563
564 rawp = skb->data;
565
566 /*
567 * This is a magic hack to spot IPX packets. Older Novell breaks
568 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
569 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
570 * won't work for fault tolerant netware but does for the rest.
571 */
572 if (*(unsigned short *)rawp == 0xFFFF)
573 return htons(ETH_P_802_3);
574
575 /*
576 * Real 802.2 LLC
577 */
578 return htons(ETH_P_802_2);
579 }
580
581 /* PLIP_RECEIVE_PACKET --- receive a packet */
582 static int
583 plip_receive_packet(struct net_device *dev, struct net_local *nl,
584 struct plip_local *snd, struct plip_local *rcv)
585 {
586 unsigned short nibble_timeout = nl->nibble;
587 unsigned char *lbuf;
588
589 switch (rcv->state) {
590 case PLIP_PK_TRIGGER:
591 DISABLE(dev->irq);
592 /* Don't need to synchronize irq, as we can safely ignore it */
593 disable_parport_interrupts (dev);
594 write_data (dev, 0x01); /* send ACK */
595 if (net_debug > 2)
596 printk(KERN_DEBUG "%s: receive start\n", dev->name);
597 rcv->state = PLIP_PK_LENGTH_LSB;
598 rcv->nibble = PLIP_NB_BEGIN;
599
600 case PLIP_PK_LENGTH_LSB:
601 if (snd->state != PLIP_PK_DONE) {
602 if (plip_receive(nl->trigger, dev,
603 &rcv->nibble, &rcv->length.b.lsb)) {
604 /* collision, here dev->tbusy == 1 */
605 rcv->state = PLIP_PK_DONE;
606 nl->is_deferred = 1;
607 nl->connection = PLIP_CN_SEND;
608 schedule_delayed_work(&nl->deferred, 1);
609 enable_parport_interrupts (dev);
610 ENABLE(dev->irq);
611 return OK;
612 }
613 } else {
614 if (plip_receive(nibble_timeout, dev,
615 &rcv->nibble, &rcv->length.b.lsb))
616 return TIMEOUT;
617 }
618 rcv->state = PLIP_PK_LENGTH_MSB;
619
620 case PLIP_PK_LENGTH_MSB:
621 if (plip_receive(nibble_timeout, dev,
622 &rcv->nibble, &rcv->length.b.msb))
623 return TIMEOUT;
624 if (rcv->length.h > dev->mtu + dev->hard_header_len
625 || rcv->length.h < 8) {
626 printk(KERN_WARNING "%s: bogus packet size %d.\n", dev->name, rcv->length.h);
627 return ERROR;
628 }
629 /* Malloc up new buffer. */
630 rcv->skb = dev_alloc_skb(rcv->length.h + 2);
631 if (rcv->skb == NULL) {
632 printk(KERN_ERR "%s: Memory squeeze.\n", dev->name);
633 return ERROR;
634 }
635 skb_reserve(rcv->skb, 2); /* Align IP on 16 byte boundaries */
636 skb_put(rcv->skb,rcv->length.h);
637 rcv->skb->dev = dev;
638 rcv->state = PLIP_PK_DATA;
639 rcv->byte = 0;
640 rcv->checksum = 0;
641
642 case PLIP_PK_DATA:
643 lbuf = rcv->skb->data;
644 do {
645 if (plip_receive(nibble_timeout, dev,
646 &rcv->nibble, &lbuf[rcv->byte]))
647 return TIMEOUT;
648 } while (++rcv->byte < rcv->length.h);
649 do {
650 rcv->checksum += lbuf[--rcv->byte];
651 } while (rcv->byte);
652 rcv->state = PLIP_PK_CHECKSUM;
653
654 case PLIP_PK_CHECKSUM:
655 if (plip_receive(nibble_timeout, dev,
656 &rcv->nibble, &rcv->data))
657 return TIMEOUT;
658 if (rcv->data != rcv->checksum) {
659 dev->stats.rx_crc_errors++;
660 if (net_debug)
661 printk(KERN_DEBUG "%s: checksum error\n", dev->name);
662 return ERROR;
663 }
664 rcv->state = PLIP_PK_DONE;
665
666 case PLIP_PK_DONE:
667 /* Inform the upper layer for the arrival of a packet. */
668 rcv->skb->protocol=plip_type_trans(rcv->skb, dev);
669 netif_rx_ni(rcv->skb);
670 dev->stats.rx_bytes += rcv->length.h;
671 dev->stats.rx_packets++;
672 rcv->skb = NULL;
673 if (net_debug > 2)
674 printk(KERN_DEBUG "%s: receive end\n", dev->name);
675
676 /* Close the connection. */
677 write_data (dev, 0x00);
678 spin_lock_irq(&nl->lock);
679 if (snd->state != PLIP_PK_DONE) {
680 nl->connection = PLIP_CN_SEND;
681 spin_unlock_irq(&nl->lock);
682 schedule_work(&nl->immediate);
683 enable_parport_interrupts (dev);
684 ENABLE(dev->irq);
685 return OK;
686 } else {
687 nl->connection = PLIP_CN_NONE;
688 spin_unlock_irq(&nl->lock);
689 enable_parport_interrupts (dev);
690 ENABLE(dev->irq);
691 return OK;
692 }
693 }
694 return OK;
695 }
696
697 /* PLIP_SEND --- send a byte (two nibbles)
698 Returns OK on success, TIMEOUT when timeout */
699 static inline int
700 plip_send(unsigned short nibble_timeout, struct net_device *dev,
701 enum plip_nibble_state *ns_p, unsigned char data)
702 {
703 unsigned char c0;
704 unsigned int cx;
705
706 switch (*ns_p) {
707 case PLIP_NB_BEGIN:
708 write_data (dev, data & 0x0f);
709 *ns_p = PLIP_NB_1;
710
711 case PLIP_NB_1:
712 write_data (dev, 0x10 | (data & 0x0f));
713 cx = nibble_timeout;
714 while (1) {
715 c0 = read_status(dev);
716 if ((c0 & 0x80) == 0)
717 break;
718 if (--cx == 0)
719 return TIMEOUT;
720 udelay(PLIP_DELAY_UNIT);
721 }
722 write_data (dev, 0x10 | (data >> 4));
723 *ns_p = PLIP_NB_2;
724
725 case PLIP_NB_2:
726 write_data (dev, (data >> 4));
727 cx = nibble_timeout;
728 while (1) {
729 c0 = read_status(dev);
730 if (c0 & 0x80)
731 break;
732 if (--cx == 0)
733 return TIMEOUT;
734 udelay(PLIP_DELAY_UNIT);
735 }
736 *ns_p = PLIP_NB_BEGIN;
737 return OK;
738 }
739 return OK;
740 }
741
742 /* PLIP_SEND_PACKET --- send a packet */
743 static int
744 plip_send_packet(struct net_device *dev, struct net_local *nl,
745 struct plip_local *snd, struct plip_local *rcv)
746 {
747 unsigned short nibble_timeout = nl->nibble;
748 unsigned char *lbuf;
749 unsigned char c0;
750 unsigned int cx;
751
752 if (snd->skb == NULL || (lbuf = snd->skb->data) == NULL) {
753 printk(KERN_DEBUG "%s: send skb lost\n", dev->name);
754 snd->state = PLIP_PK_DONE;
755 snd->skb = NULL;
756 return ERROR;
757 }
758
759 switch (snd->state) {
760 case PLIP_PK_TRIGGER:
761 if ((read_status(dev) & 0xf8) != 0x80)
762 return HS_TIMEOUT;
763
764 /* Trigger remote rx interrupt. */
765 write_data (dev, 0x08);
766 cx = nl->trigger;
767 while (1) {
768 udelay(PLIP_DELAY_UNIT);
769 spin_lock_irq(&nl->lock);
770 if (nl->connection == PLIP_CN_RECEIVE) {
771 spin_unlock_irq(&nl->lock);
772 /* Interrupted. */
773 dev->stats.collisions++;
774 return OK;
775 }
776 c0 = read_status(dev);
777 if (c0 & 0x08) {
778 spin_unlock_irq(&nl->lock);
779 DISABLE(dev->irq);
780 synchronize_irq(dev->irq);
781 if (nl->connection == PLIP_CN_RECEIVE) {
782 /* Interrupted.
783 We don't need to enable irq,
784 as it is soon disabled. */
785 /* Yes, we do. New variant of
786 {enable,disable}_irq *counts*
787 them. -- AV */
788 ENABLE(dev->irq);
789 dev->stats.collisions++;
790 return OK;
791 }
792 disable_parport_interrupts (dev);
793 if (net_debug > 2)
794 printk(KERN_DEBUG "%s: send start\n", dev->name);
795 snd->state = PLIP_PK_LENGTH_LSB;
796 snd->nibble = PLIP_NB_BEGIN;
797 nl->timeout_count = 0;
798 break;
799 }
800 spin_unlock_irq(&nl->lock);
801 if (--cx == 0) {
802 write_data (dev, 0x00);
803 return HS_TIMEOUT;
804 }
805 }
806
807 case PLIP_PK_LENGTH_LSB:
808 if (plip_send(nibble_timeout, dev,
809 &snd->nibble, snd->length.b.lsb))
810 return TIMEOUT;
811 snd->state = PLIP_PK_LENGTH_MSB;
812
813 case PLIP_PK_LENGTH_MSB:
814 if (plip_send(nibble_timeout, dev,
815 &snd->nibble, snd->length.b.msb))
816 return TIMEOUT;
817 snd->state = PLIP_PK_DATA;
818 snd->byte = 0;
819 snd->checksum = 0;
820
821 case PLIP_PK_DATA:
822 do {
823 if (plip_send(nibble_timeout, dev,
824 &snd->nibble, lbuf[snd->byte]))
825 return TIMEOUT;
826 } while (++snd->byte < snd->length.h);
827 do {
828 snd->checksum += lbuf[--snd->byte];
829 } while (snd->byte);
830 snd->state = PLIP_PK_CHECKSUM;
831
832 case PLIP_PK_CHECKSUM:
833 if (plip_send(nibble_timeout, dev,
834 &snd->nibble, snd->checksum))
835 return TIMEOUT;
836
837 dev->stats.tx_bytes += snd->skb->len;
838 dev_kfree_skb(snd->skb);
839 dev->stats.tx_packets++;
840 snd->state = PLIP_PK_DONE;
841
842 case PLIP_PK_DONE:
843 /* Close the connection */
844 write_data (dev, 0x00);
845 snd->skb = NULL;
846 if (net_debug > 2)
847 printk(KERN_DEBUG "%s: send end\n", dev->name);
848 nl->connection = PLIP_CN_CLOSING;
849 nl->is_deferred = 1;
850 schedule_delayed_work(&nl->deferred, 1);
851 enable_parport_interrupts (dev);
852 ENABLE(dev->irq);
853 return OK;
854 }
855 return OK;
856 }
857
858 static int
859 plip_connection_close(struct net_device *dev, struct net_local *nl,
860 struct plip_local *snd, struct plip_local *rcv)
861 {
862 spin_lock_irq(&nl->lock);
863 if (nl->connection == PLIP_CN_CLOSING) {
864 nl->connection = PLIP_CN_NONE;
865 netif_wake_queue (dev);
866 }
867 spin_unlock_irq(&nl->lock);
868 if (nl->should_relinquish) {
869 nl->should_relinquish = nl->port_owner = 0;
870 parport_release(nl->pardev);
871 }
872 return OK;
873 }
874
875 /* PLIP_ERROR --- wait till other end settled */
876 static int
877 plip_error(struct net_device *dev, struct net_local *nl,
878 struct plip_local *snd, struct plip_local *rcv)
879 {
880 unsigned char status;
881
882 status = read_status(dev);
883 if ((status & 0xf8) == 0x80) {
884 if (net_debug > 2)
885 printk(KERN_DEBUG "%s: reset interface.\n", dev->name);
886 nl->connection = PLIP_CN_NONE;
887 nl->should_relinquish = 0;
888 netif_start_queue (dev);
889 enable_parport_interrupts (dev);
890 ENABLE(dev->irq);
891 netif_wake_queue (dev);
892 } else {
893 nl->is_deferred = 1;
894 schedule_delayed_work(&nl->deferred, 1);
895 }
896
897 return OK;
898 }
899
900 /* Handle the parallel port interrupts. */
901 static void
902 plip_interrupt(void *dev_id)
903 {
904 struct net_device *dev = dev_id;
905 struct net_local *nl;
906 struct plip_local *rcv;
907 unsigned char c0;
908 unsigned long flags;
909
910 nl = netdev_priv(dev);
911 rcv = &nl->rcv_data;
912
913 spin_lock_irqsave (&nl->lock, flags);
914
915 c0 = read_status(dev);
916 if ((c0 & 0xf8) != 0xc0) {
917 if ((dev->irq != -1) && (net_debug > 1))
918 printk(KERN_DEBUG "%s: spurious interrupt\n", dev->name);
919 spin_unlock_irqrestore (&nl->lock, flags);
920 return;
921 }
922
923 if (net_debug > 3)
924 printk(KERN_DEBUG "%s: interrupt.\n", dev->name);
925
926 switch (nl->connection) {
927 case PLIP_CN_CLOSING:
928 netif_wake_queue (dev);
929 case PLIP_CN_NONE:
930 case PLIP_CN_SEND:
931 rcv->state = PLIP_PK_TRIGGER;
932 nl->connection = PLIP_CN_RECEIVE;
933 nl->timeout_count = 0;
934 schedule_work(&nl->immediate);
935 break;
936
937 case PLIP_CN_RECEIVE:
938 /* May occur because there is race condition
939 around test and set of dev->interrupt.
940 Ignore this interrupt. */
941 break;
942
943 case PLIP_CN_ERROR:
944 printk(KERN_ERR "%s: receive interrupt in error state\n", dev->name);
945 break;
946 }
947
948 spin_unlock_irqrestore(&nl->lock, flags);
949 }
950
951 static int
952 plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
953 {
954 struct net_local *nl = netdev_priv(dev);
955 struct plip_local *snd = &nl->snd_data;
956
957 if (netif_queue_stopped(dev))
958 return 1;
959
960 /* We may need to grab the bus */
961 if (!nl->port_owner) {
962 if (parport_claim(nl->pardev))
963 return 1;
964 nl->port_owner = 1;
965 }
966
967 netif_stop_queue (dev);
968
969 if (skb->len > dev->mtu + dev->hard_header_len) {
970 printk(KERN_WARNING "%s: packet too big, %d.\n", dev->name, (int)skb->len);
971 netif_start_queue (dev);
972 return 1;
973 }
974
975 if (net_debug > 2)
976 printk(KERN_DEBUG "%s: send request\n", dev->name);
977
978 spin_lock_irq(&nl->lock);
979 dev->trans_start = jiffies;
980 snd->skb = skb;
981 snd->length.h = skb->len;
982 snd->state = PLIP_PK_TRIGGER;
983 if (nl->connection == PLIP_CN_NONE) {
984 nl->connection = PLIP_CN_SEND;
985 nl->timeout_count = 0;
986 }
987 schedule_work(&nl->immediate);
988 spin_unlock_irq(&nl->lock);
989
990 return 0;
991 }
992
993 static void
994 plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
995 {
996 const struct in_device *in_dev = dev->ip_ptr;
997
998 if (in_dev) {
999 /* Any address will do - we take the first */
1000 const struct in_ifaddr *ifa = in_dev->ifa_list;
1001 if (ifa) {
1002 memcpy(eth->h_source, dev->dev_addr, 6);
1003 memset(eth->h_dest, 0xfc, 2);
1004 memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
1005 }
1006 }
1007 }
1008
1009 static int
1010 plip_hard_header(struct sk_buff *skb, struct net_device *dev,
1011 unsigned short type, const void *daddr,
1012 const void *saddr, unsigned len)
1013 {
1014 int ret;
1015
1016 ret = eth_header(skb, dev, type, daddr, saddr, len);
1017 if (ret >= 0)
1018 plip_rewrite_address (dev, (struct ethhdr *)skb->data);
1019
1020 return ret;
1021 }
1022
1023 static int plip_hard_header_cache(const struct neighbour *neigh,
1024 struct hh_cache *hh)
1025 {
1026 int ret;
1027
1028 ret = eth_header_cache(neigh, hh);
1029 if (ret == 0) {
1030 struct ethhdr *eth;
1031
1032 eth = (struct ethhdr*)(((u8*)hh->hh_data) +
1033 HH_DATA_OFF(sizeof(*eth)));
1034 plip_rewrite_address (neigh->dev, eth);
1035 }
1036
1037 return ret;
1038 }
1039
1040 /* Open/initialize the board. This is called (in the current kernel)
1041 sometime after booting when the 'ifconfig' program is run.
1042
1043 This routine gets exclusive access to the parallel port by allocating
1044 its IRQ line.
1045 */
1046 static int
1047 plip_open(struct net_device *dev)
1048 {
1049 struct net_local *nl = netdev_priv(dev);
1050 struct in_device *in_dev;
1051
1052 /* Grab the port */
1053 if (!nl->port_owner) {
1054 if (parport_claim(nl->pardev)) return -EAGAIN;
1055 nl->port_owner = 1;
1056 }
1057
1058 nl->should_relinquish = 0;
1059
1060 /* Clear the data port. */
1061 write_data (dev, 0x00);
1062
1063 /* Enable rx interrupt. */
1064 enable_parport_interrupts (dev);
1065 if (dev->irq == -1)
1066 {
1067 atomic_set (&nl->kill_timer, 0);
1068 schedule_delayed_work(&nl->timer, 1);
1069 }
1070
1071 /* Initialize the state machine. */
1072 nl->rcv_data.state = nl->snd_data.state = PLIP_PK_DONE;
1073 nl->rcv_data.skb = nl->snd_data.skb = NULL;
1074 nl->connection = PLIP_CN_NONE;
1075 nl->is_deferred = 0;
1076
1077 /* Fill in the MAC-level header.
1078 We used to abuse dev->broadcast to store the point-to-point
1079 MAC address, but we no longer do it. Instead, we fetch the
1080 interface address whenever it is needed, which is cheap enough
1081 because we use the hh_cache. Actually, abusing dev->broadcast
1082 didn't work, because when using plip_open the point-to-point
1083 address isn't yet known.
1084 PLIP doesn't have a real MAC address, but we need it to be
1085 DOS compatible, and to properly support taps (otherwise,
1086 when the device address isn't identical to the address of a
1087 received frame, the kernel incorrectly drops it). */
1088
1089 if ((in_dev=dev->ip_ptr) != NULL) {
1090 /* Any address will do - we take the first. We already
1091 have the first two bytes filled with 0xfc, from
1092 plip_init_dev(). */
1093 struct in_ifaddr *ifa=in_dev->ifa_list;
1094 if (ifa != NULL) {
1095 memcpy(dev->dev_addr+2, &ifa->ifa_local, 4);
1096 }
1097 }
1098
1099 netif_start_queue (dev);
1100
1101 return 0;
1102 }
1103
1104 /* The inverse routine to plip_open (). */
1105 static int
1106 plip_close(struct net_device *dev)
1107 {
1108 struct net_local *nl = netdev_priv(dev);
1109 struct plip_local *snd = &nl->snd_data;
1110 struct plip_local *rcv = &nl->rcv_data;
1111
1112 netif_stop_queue (dev);
1113 DISABLE(dev->irq);
1114 synchronize_irq(dev->irq);
1115
1116 if (dev->irq == -1)
1117 {
1118 init_completion(&nl->killed_timer_cmp);
1119 atomic_set (&nl->kill_timer, 1);
1120 wait_for_completion(&nl->killed_timer_cmp);
1121 }
1122
1123 #ifdef NOTDEF
1124 outb(0x00, PAR_DATA(dev));
1125 #endif
1126 nl->is_deferred = 0;
1127 nl->connection = PLIP_CN_NONE;
1128 if (nl->port_owner) {
1129 parport_release(nl->pardev);
1130 nl->port_owner = 0;
1131 }
1132
1133 snd->state = PLIP_PK_DONE;
1134 if (snd->skb) {
1135 dev_kfree_skb(snd->skb);
1136 snd->skb = NULL;
1137 }
1138 rcv->state = PLIP_PK_DONE;
1139 if (rcv->skb) {
1140 kfree_skb(rcv->skb);
1141 rcv->skb = NULL;
1142 }
1143
1144 #ifdef NOTDEF
1145 /* Reset. */
1146 outb(0x00, PAR_CONTROL(dev));
1147 #endif
1148 return 0;
1149 }
1150
1151 static int
1152 plip_preempt(void *handle)
1153 {
1154 struct net_device *dev = (struct net_device *)handle;
1155 struct net_local *nl = netdev_priv(dev);
1156
1157 /* Stand our ground if a datagram is on the wire */
1158 if (nl->connection != PLIP_CN_NONE) {
1159 nl->should_relinquish = 1;
1160 return 1;
1161 }
1162
1163 nl->port_owner = 0; /* Remember that we released the bus */
1164 return 0;
1165 }
1166
1167 static void
1168 plip_wakeup(void *handle)
1169 {
1170 struct net_device *dev = (struct net_device *)handle;
1171 struct net_local *nl = netdev_priv(dev);
1172
1173 if (nl->port_owner) {
1174 /* Why are we being woken up? */
1175 printk(KERN_DEBUG "%s: why am I being woken up?\n", dev->name);
1176 if (!parport_claim(nl->pardev))
1177 /* bus_owner is already set (but why?) */
1178 printk(KERN_DEBUG "%s: I'm broken.\n", dev->name);
1179 else
1180 return;
1181 }
1182
1183 if (!(dev->flags & IFF_UP))
1184 /* Don't need the port when the interface is down */
1185 return;
1186
1187 if (!parport_claim(nl->pardev)) {
1188 nl->port_owner = 1;
1189 /* Clear the data port. */
1190 write_data (dev, 0x00);
1191 }
1192
1193 return;
1194 }
1195
1196 static int
1197 plip_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1198 {
1199 struct net_local *nl = netdev_priv(dev);
1200 struct plipconf *pc = (struct plipconf *) &rq->ifr_ifru;
1201
1202 if (cmd != SIOCDEVPLIP)
1203 return -EOPNOTSUPP;
1204
1205 switch(pc->pcmd) {
1206 case PLIP_GET_TIMEOUT:
1207 pc->trigger = nl->trigger;
1208 pc->nibble = nl->nibble;
1209 break;
1210 case PLIP_SET_TIMEOUT:
1211 if(!capable(CAP_NET_ADMIN))
1212 return -EPERM;
1213 nl->trigger = pc->trigger;
1214 nl->nibble = pc->nibble;
1215 break;
1216 default:
1217 return -EOPNOTSUPP;
1218 }
1219 return 0;
1220 }
1221
1222 static int parport[PLIP_MAX] = { [0 ... PLIP_MAX-1] = -1 };
1223 static int timid;
1224
1225 module_param_array(parport, int, NULL, 0);
1226 module_param(timid, int, 0);
1227 MODULE_PARM_DESC(parport, "List of parport device numbers to use by plip");
1228
1229 static struct net_device *dev_plip[PLIP_MAX] = { NULL, };
1230
1231 static inline int
1232 plip_searchfor(int list[], int a)
1233 {
1234 int i;
1235 for (i = 0; i < PLIP_MAX && list[i] != -1; i++) {
1236 if (list[i] == a) return 1;
1237 }
1238 return 0;
1239 }
1240
1241 /* plip_attach() is called (by the parport code) when a port is
1242 * available to use. */
1243 static void plip_attach (struct parport *port)
1244 {
1245 static int unit;
1246 struct net_device *dev;
1247 struct net_local *nl;
1248 char name[IFNAMSIZ];
1249
1250 if ((parport[0] == -1 && (!timid || !port->devices)) ||
1251 plip_searchfor(parport, port->number)) {
1252 if (unit == PLIP_MAX) {
1253 printk(KERN_ERR "plip: too many devices\n");
1254 return;
1255 }
1256
1257 sprintf(name, "plip%d", unit);
1258 dev = alloc_etherdev(sizeof(struct net_local));
1259 if (!dev) {
1260 printk(KERN_ERR "plip: memory squeeze\n");
1261 return;
1262 }
1263
1264 strcpy(dev->name, name);
1265
1266 dev->irq = port->irq;
1267 dev->base_addr = port->base;
1268 if (port->irq == -1) {
1269 printk(KERN_INFO "plip: %s has no IRQ. Using IRQ-less mode,"
1270 "which is fairly inefficient!\n", port->name);
1271 }
1272
1273 nl = netdev_priv(dev);
1274 nl->dev = dev;
1275 nl->pardev = parport_register_device(port, dev->name, plip_preempt,
1276 plip_wakeup, plip_interrupt,
1277 0, dev);
1278
1279 if (!nl->pardev) {
1280 printk(KERN_ERR "%s: parport_register failed\n", name);
1281 goto err_free_dev;
1282 return;
1283 }
1284
1285 plip_init_netdev(dev);
1286
1287 if (register_netdev(dev)) {
1288 printk(KERN_ERR "%s: network register failed\n", name);
1289 goto err_parport_unregister;
1290 }
1291
1292 printk(KERN_INFO "%s", version);
1293 if (dev->irq != -1)
1294 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1295 "using IRQ %d.\n",
1296 dev->name, dev->base_addr, dev->irq);
1297 else
1298 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1299 "not using IRQ.\n",
1300 dev->name, dev->base_addr);
1301 dev_plip[unit++] = dev;
1302 }
1303 return;
1304
1305 err_parport_unregister:
1306 parport_unregister_device(nl->pardev);
1307 err_free_dev:
1308 free_netdev(dev);
1309 return;
1310 }
1311
1312 /* plip_detach() is called (by the parport code) when a port is
1313 * no longer available to use. */
1314 static void plip_detach (struct parport *port)
1315 {
1316 /* Nothing to do */
1317 }
1318
1319 static struct parport_driver plip_driver = {
1320 .name = "plip",
1321 .attach = plip_attach,
1322 .detach = plip_detach
1323 };
1324
1325 static void __exit plip_cleanup_module (void)
1326 {
1327 struct net_device *dev;
1328 int i;
1329
1330 parport_unregister_driver (&plip_driver);
1331
1332 for (i=0; i < PLIP_MAX; i++) {
1333 if ((dev = dev_plip[i])) {
1334 struct net_local *nl = netdev_priv(dev);
1335 unregister_netdev(dev);
1336 if (nl->port_owner)
1337 parport_release(nl->pardev);
1338 parport_unregister_device(nl->pardev);
1339 free_netdev(dev);
1340 dev_plip[i] = NULL;
1341 }
1342 }
1343 }
1344
1345 #ifndef MODULE
1346
1347 static int parport_ptr;
1348
1349 static int __init plip_setup(char *str)
1350 {
1351 int ints[4];
1352
1353 str = get_options(str, ARRAY_SIZE(ints), ints);
1354
1355 /* Ugh. */
1356 if (!strncmp(str, "parport", 7)) {
1357 int n = simple_strtoul(str+7, NULL, 10);
1358 if (parport_ptr < PLIP_MAX)
1359 parport[parport_ptr++] = n;
1360 else
1361 printk(KERN_INFO "plip: too many ports, %s ignored.\n",
1362 str);
1363 } else if (!strcmp(str, "timid")) {
1364 timid = 1;
1365 } else {
1366 if (ints[0] == 0 || ints[1] == 0) {
1367 /* disable driver on "plip=" or "plip=0" */
1368 parport[0] = -2;
1369 } else {
1370 printk(KERN_WARNING "warning: 'plip=0x%x' ignored\n",
1371 ints[1]);
1372 }
1373 }
1374 return 1;
1375 }
1376
1377 __setup("plip=", plip_setup);
1378
1379 #endif /* !MODULE */
1380
1381 static int __init plip_init (void)
1382 {
1383 if (parport[0] == -2)
1384 return 0;
1385
1386 if (parport[0] != -1 && timid) {
1387 printk(KERN_WARNING "plip: warning, ignoring `timid' since specific ports given.\n");
1388 timid = 0;
1389 }
1390
1391 if (parport_register_driver (&plip_driver)) {
1392 printk (KERN_WARNING "plip: couldn't register driver\n");
1393 return 1;
1394 }
1395
1396 return 0;
1397 }
1398
1399 module_init(plip_init);
1400 module_exit(plip_cleanup_module);
1401 MODULE_LICENSE("GPL");
Support for the Chinese Samsung S3C2440 based development boards