1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* $Id: plip.c,v 1.3.6.2 1997/04/16 15:07:56 phil Exp $ */
3 /* PLIP: A parallel port "network" driver for Linux. */
4 /* This driver is for parallel port with 5-bit cable (LapLink (R) cable). */
5 /*
6 * Authors: Donald Becker <becker@scyld.com>
7 * Tommy Thorn <thorn@daimi.aau.dk>
8 * Tanabe Hiroyasu <hiro@sanpo.t.u-tokyo.ac.jp>
9 * Alan Cox <gw4pts@gw4pts.ampr.org>
10 * Peter Bauer <100136.3530@compuserve.com>
11 * Niibe Yutaka <gniibe@mri.co.jp>
12 * Nimrod Zimerman <zimerman@mailandnews.com>
13 *
14 * Enhancements:
15 * Modularization and ifreq/ifmap support by Alan Cox.
16 * Rewritten by Niibe Yutaka.
17 * parport-sharing awareness code by Philip Blundell.
18 * SMP locking by Niibe Yutaka.
19 * Support for parallel ports with no IRQ (poll mode),
20 * Modifications to use the parallel port API
21 * by Nimrod Zimerman.
22 *
23 * Fixes:
24 * Niibe Yutaka
25 * - Module initialization.
26 * - MTU fix.
27 * - Make sure other end is OK, before sending a packet.
28 * - Fix immediate timer problem.
29 *
30 * Al Viro
31 * - Changed {enable,disable}_irq handling to make it work
32 * with new ("stack") semantics.
33 */
34
35 /*
36 * Original version and the name 'PLIP' from Donald Becker <becker@scyld.com>
37 * inspired by Russ Nelson's parallel port packet driver.
38 *
39 * NOTE:
40 * Tanabe Hiroyasu had changed the protocol, and it was in Linux v1.0.
41 * Because of the necessity to communicate to DOS machines with the
42 * Crynwr packet driver, Peter Bauer changed the protocol again
43 * back to original protocol.
44 *
45 * This version follows original PLIP protocol.
46 * So, this PLIP can't communicate the PLIP of Linux v1.0.
47 */
48
49 /*
50 * To use with DOS box, please do (Turn on ARP switch):
51 * # ifconfig plip[0-2] arp
52 */
53 static const char version[] = "NET3 PLIP version 2.4-parport gniibe@mri.co.jp\n";
54
55 /*
56 Sources:
57 Ideas and protocols came from Russ Nelson's <nelson@crynwr.com>
58 "parallel.asm" parallel port packet driver.
59
60 The "Crynwr" parallel port standard specifies the following protocol:
61 Trigger by sending nibble '0x8' (this causes interrupt on other end)
62 count-low octet
63 count-high octet
64 ... data octets
65 checksum octet
66 Each octet is sent as <wait for rx. '0x1?'> <send 0x10+(octet&0x0F)>
67 <wait for rx. '0x0?'> <send 0x00+((octet>>4)&0x0F)>
68
69 The packet is encapsulated as if it were ethernet.
70
71 The cable used is a de facto standard parallel null cable -- sold as
72 a "LapLink" cable by various places. You'll need a 12-conductor cable to
73 make one yourself. The wiring is:
74 SLCTIN 17 - 17
75 GROUND 25 - 25
76 D0->ERROR 2 - 15 15 - 2
77 D1->SLCT 3 - 13 13 - 3
78 D2->PAPOUT 4 - 12 12 - 4
79 D3->ACK 5 - 10 10 - 5
80 D4->BUSY 6 - 11 11 - 6
81 Do not connect the other pins. They are
82 D5,D6,D7 are 7,8,9
83 STROBE is 1, FEED is 14, INIT is 16
84 extra grounds are 18,19,20,21,22,23,24
85 */
86
87 #include <linux/compat.h>
88 #include <linux/module.h>
89 #include <linux/kernel.h>
90 #include <linux/types.h>
91 #include <linux/fcntl.h>
92 #include <linux/interrupt.h>
93 #include <linux/string.h>
94 #include <linux/slab.h>
95 #include <linux/if_ether.h>
96 #include <linux/in.h>
97 #include <linux/errno.h>
98 #include <linux/delay.h>
99 #include <linux/init.h>
100 #include <linux/netdevice.h>
101 #include <linux/etherdevice.h>
102 #include <linux/inetdevice.h>
103 #include <linux/skbuff.h>
104 #include <linux/if_plip.h>
105 #include <linux/workqueue.h>
106 #include <linux/spinlock.h>
107 #include <linux/completion.h>
108 #include <linux/parport.h>
109 #include <linux/bitops.h>
110
111 #include <net/neighbour.h>
112
113 #include <asm/irq.h>
114 #include <asm/byteorder.h>
115
116 /* Maximum number of devices to support. */
117 #define PLIP_MAX 8
118
119 /* Use 0 for production, 1 for verification, >2 for debug */
120 #ifndef NET_DEBUG
121 #define NET_DEBUG 1
122 #endif
123 static const unsigned int net_debug = NET_DEBUG;
124
125 #define ENABLE(irq) if (irq != -1) enable_irq(irq)
126 #define DISABLE(irq) if (irq != -1) disable_irq(irq)
127
128 /* In micro second */
129 #define PLIP_DELAY_UNIT 1
130
131 /* Connection time out = PLIP_TRIGGER_WAIT * PLIP_DELAY_UNIT usec */
132 #define PLIP_TRIGGER_WAIT 500
133
134 /* Nibble time out = PLIP_NIBBLE_WAIT * PLIP_DELAY_UNIT usec */
135 #define PLIP_NIBBLE_WAIT 3000
136
137 /* Bottom halves */
138 static void plip_kick_bh(struct work_struct *work);
139 static void plip_bh(struct work_struct *work);
140 static void plip_timer_bh(struct work_struct *work);
141
142 /* Interrupt handler */
143 static void plip_interrupt(void *dev_id);
144
145 /* Functions for DEV methods */
146 static netdev_tx_t plip_tx_packet(struct sk_buff *skb, struct net_device *dev);
147 static int plip_hard_header(struct sk_buff *skb, struct net_device *dev,
148 unsigned short type, const void *daddr,
149 const void *saddr, unsigned len);
150 static int plip_hard_header_cache(const struct neighbour *neigh,
151 struct hh_cache *hh, __be16 type);
152 static int plip_open(struct net_device *dev);
153 static int plip_close(struct net_device *dev);
154 static int plip_siocdevprivate(struct net_device *dev, struct ifreq *ifr,
155 void __user *data, int cmd);
156 static int plip_preempt(void *handle);
157 static void plip_wakeup(void *handle);
158
159 enum plip_connection_state {
160 PLIP_CN_NONE=0,
161 PLIP_CN_RECEIVE,
162 PLIP_CN_SEND,
163 PLIP_CN_CLOSING,
164 PLIP_CN_ERROR
165 };
166
167 enum plip_packet_state {
168 PLIP_PK_DONE=0,
169 PLIP_PK_TRIGGER,
170 PLIP_PK_LENGTH_LSB,
171 PLIP_PK_LENGTH_MSB,
172 PLIP_PK_DATA,
173 PLIP_PK_CHECKSUM
174 };
175
176 enum plip_nibble_state {
177 PLIP_NB_BEGIN,
178 PLIP_NB_1,
179 PLIP_NB_2,
180 };
181
182 struct plip_local {
183 enum plip_packet_state state;
184 enum plip_nibble_state nibble;
185 union {
186 struct {
187 #if defined(__LITTLE_ENDIAN)
188 unsigned char lsb;
189 unsigned char msb;
190 #elif defined(__BIG_ENDIAN)
191 unsigned char msb;
192 unsigned char lsb;
193 #else
194 #error "Please fix the endianness defines in <asm/byteorder.h>"
195 #endif
196 } b;
197 unsigned short h;
198 } length;
199 unsigned short byte;
200 unsigned char checksum;
201 unsigned char data;
202 struct sk_buff *skb;
203 };
204
205 struct net_local {
206 struct net_device *dev;
207 struct work_struct immediate;
208 struct delayed_work deferred;
209 struct delayed_work timer;
210 struct plip_local snd_data;
211 struct plip_local rcv_data;
212 struct pardevice *pardev;
213 unsigned long trigger;
214 unsigned long nibble;
215 enum plip_connection_state connection;
216 unsigned short timeout_count;
217 int is_deferred;
218 int port_owner;
219 int should_relinquish;
220 spinlock_t lock;
221 atomic_t kill_timer;
222 struct completion killed_timer_cmp;
223 };
224
enable_parport_interrupts(struct net_device * dev)225 static inline void enable_parport_interrupts (struct net_device *dev)
226 {
227 if (dev->irq != -1)
228 {
229 struct parport *port =
230 ((struct net_local *)netdev_priv(dev))->pardev->port;
231 port->ops->enable_irq (port);
232 }
233 }
234
disable_parport_interrupts(struct net_device * dev)235 static inline void disable_parport_interrupts (struct net_device *dev)
236 {
237 if (dev->irq != -1)
238 {
239 struct parport *port =
240 ((struct net_local *)netdev_priv(dev))->pardev->port;
241 port->ops->disable_irq (port);
242 }
243 }
244
write_data(struct net_device * dev,unsigned char data)245 static inline void write_data (struct net_device *dev, unsigned char data)
246 {
247 struct parport *port =
248 ((struct net_local *)netdev_priv(dev))->pardev->port;
249
250 port->ops->write_data (port, data);
251 }
252
read_status(struct net_device * dev)253 static inline unsigned char read_status (struct net_device *dev)
254 {
255 struct parport *port =
256 ((struct net_local *)netdev_priv(dev))->pardev->port;
257
258 return port->ops->read_status (port);
259 }
260
261 static const struct header_ops plip_header_ops = {
262 .create = plip_hard_header,
263 .cache = plip_hard_header_cache,
264 };
265
266 static const struct net_device_ops plip_netdev_ops = {
267 .ndo_open = plip_open,
268 .ndo_stop = plip_close,
269 .ndo_start_xmit = plip_tx_packet,
270 .ndo_siocdevprivate = plip_siocdevprivate,
271 .ndo_set_mac_address = eth_mac_addr,
272 .ndo_validate_addr = eth_validate_addr,
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
plip_init_netdev(struct net_device * dev)285 plip_init_netdev(struct net_device *dev)
286 {
287 static const u8 addr_init[ETH_ALEN] = {
288 0xfc, 0xfc, 0xfc,
289 0xfc, 0xfc, 0xfc,
290 };
291 struct net_local *nl = netdev_priv(dev);
292
293 /* Then, override parts of it */
294 dev->tx_queue_len = 10;
295 dev->flags = IFF_POINTOPOINT|IFF_NOARP;
296 eth_hw_addr_set(dev, addr_init);
297
298 dev->netdev_ops = &plip_netdev_ops;
299 dev->header_ops = &plip_header_ops;
300
301
302 nl->port_owner = 0;
303
304 /* Initialize constants */
305 nl->trigger = PLIP_TRIGGER_WAIT;
306 nl->nibble = PLIP_NIBBLE_WAIT;
307
308 /* Initialize task queue structures */
309 INIT_WORK(&nl->immediate, plip_bh);
310 INIT_DELAYED_WORK(&nl->deferred, plip_kick_bh);
311
312 if (dev->irq == -1)
313 INIT_DELAYED_WORK(&nl->timer, plip_timer_bh);
314
315 spin_lock_init(&nl->lock);
316 }
317
318 /* Bottom half handler for the delayed request.
319 This routine is kicked by do_timer().
320 Request `plip_bh' to be invoked. */
321 static void
plip_kick_bh(struct work_struct * work)322 plip_kick_bh(struct work_struct *work)
323 {
324 struct net_local *nl =
325 container_of(work, struct net_local, deferred.work);
326
327 if (nl->is_deferred)
328 schedule_work(&nl->immediate);
329 }
330
331 /* Forward declarations of internal routines */
332 static int plip_none(struct net_device *, struct net_local *,
333 struct plip_local *, struct plip_local *);
334 static int plip_receive_packet(struct net_device *, struct net_local *,
335 struct plip_local *, struct plip_local *);
336 static int plip_send_packet(struct net_device *, struct net_local *,
337 struct plip_local *, struct plip_local *);
338 static int plip_connection_close(struct net_device *, struct net_local *,
339 struct plip_local *, struct plip_local *);
340 static int plip_error(struct net_device *, struct net_local *,
341 struct plip_local *, struct plip_local *);
342 static int plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
343 struct plip_local *snd,
344 struct plip_local *rcv,
345 int error);
346
347 #define OK 0
348 #define TIMEOUT 1
349 #define ERROR 2
350 #define HS_TIMEOUT 3
351
352 typedef int (*plip_func)(struct net_device *dev, struct net_local *nl,
353 struct plip_local *snd, struct plip_local *rcv);
354
355 static const plip_func connection_state_table[] =
356 {
357 plip_none,
358 plip_receive_packet,
359 plip_send_packet,
360 plip_connection_close,
361 plip_error
362 };
363
364 /* Bottom half handler of PLIP. */
365 static void
plip_bh(struct work_struct * work)366 plip_bh(struct work_struct *work)
367 {
368 struct net_local *nl = container_of(work, struct net_local, immediate);
369 struct plip_local *snd = &nl->snd_data;
370 struct plip_local *rcv = &nl->rcv_data;
371 plip_func f;
372 int r;
373
374 nl->is_deferred = 0;
375 f = connection_state_table[nl->connection];
376 if ((r = (*f)(nl->dev, nl, snd, rcv)) != OK &&
377 (r = plip_bh_timeout_error(nl->dev, nl, snd, rcv, r)) != OK) {
378 nl->is_deferred = 1;
379 schedule_delayed_work(&nl->deferred, 1);
380 }
381 }
382
383 static void
plip_timer_bh(struct work_struct * work)384 plip_timer_bh(struct work_struct *work)
385 {
386 struct net_local *nl =
387 container_of(work, struct net_local, timer.work);
388
389 if (!(atomic_read (&nl->kill_timer))) {
390 plip_interrupt (nl->dev);
391
392 schedule_delayed_work(&nl->timer, 1);
393 }
394 else {
395 complete(&nl->killed_timer_cmp);
396 }
397 }
398
399 static int
plip_bh_timeout_error(struct net_device * dev,struct net_local * nl,struct plip_local * snd,struct plip_local * rcv,int error)400 plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
401 struct plip_local *snd, struct plip_local *rcv,
402 int error)
403 {
404 unsigned char c0;
405 /*
406 * This is tricky. If we got here from the beginning of send (either
407 * with ERROR or HS_TIMEOUT) we have IRQ enabled. Otherwise it's
408 * already disabled. With the old variant of {enable,disable}_irq()
409 * extra disable_irq() was a no-op. Now it became mortal - it's
410 * unbalanced and thus we'll never re-enable IRQ (until rmmod plip,
411 * that is). So we have to treat HS_TIMEOUT and ERROR from send
412 * in a special way.
413 */
414
415 spin_lock_irq(&nl->lock);
416 if (nl->connection == PLIP_CN_SEND) {
417
418 if (error != ERROR) { /* Timeout */
419 nl->timeout_count++;
420 if ((error == HS_TIMEOUT && nl->timeout_count <= 10) ||
421 nl->timeout_count <= 3) {
422 spin_unlock_irq(&nl->lock);
423 /* Try again later */
424 return TIMEOUT;
425 }
426 c0 = read_status(dev);
427 printk(KERN_WARNING "%s: transmit timeout(%d,%02x)\n",
428 dev->name, snd->state, c0);
429 } else
430 error = HS_TIMEOUT;
431 dev->stats.tx_errors++;
432 dev->stats.tx_aborted_errors++;
433 } else if (nl->connection == PLIP_CN_RECEIVE) {
434 if (rcv->state == PLIP_PK_TRIGGER) {
435 /* Transmission was interrupted. */
436 spin_unlock_irq(&nl->lock);
437 return OK;
438 }
439 if (error != ERROR) { /* Timeout */
440 if (++nl->timeout_count <= 3) {
441 spin_unlock_irq(&nl->lock);
442 /* Try again later */
443 return TIMEOUT;
444 }
445 c0 = read_status(dev);
446 printk(KERN_WARNING "%s: receive timeout(%d,%02x)\n",
447 dev->name, rcv->state, c0);
448 }
449 dev->stats.rx_dropped++;
450 }
451 rcv->state = PLIP_PK_DONE;
452 if (rcv->skb) {
453 dev_kfree_skb_irq(rcv->skb);
454 rcv->skb = NULL;
455 }
456 snd->state = PLIP_PK_DONE;
457 if (snd->skb) {
458 dev_consume_skb_irq(snd->skb);
459 snd->skb = NULL;
460 }
461 spin_unlock_irq(&nl->lock);
462 if (error == HS_TIMEOUT) {
463 DISABLE(dev->irq);
464 synchronize_irq(dev->irq);
465 }
466 disable_parport_interrupts (dev);
467 netif_stop_queue (dev);
468 nl->connection = PLIP_CN_ERROR;
469 write_data (dev, 0x00);
470
471 return TIMEOUT;
472 }
473
474 static int
plip_none(struct net_device * dev,struct net_local * nl,struct plip_local * snd,struct plip_local * rcv)475 plip_none(struct net_device *dev, struct net_local *nl,
476 struct plip_local *snd, struct plip_local *rcv)
477 {
478 return OK;
479 }
480
481 /* PLIP_RECEIVE --- receive a byte(two nibbles)
482 Returns OK on success, TIMEOUT on timeout */
483 static inline int
plip_receive(unsigned short nibble_timeout,struct net_device * dev,enum plip_nibble_state * ns_p,unsigned char * data_p)484 plip_receive(unsigned short nibble_timeout, struct net_device *dev,
485 enum plip_nibble_state *ns_p, unsigned char *data_p)
486 {
487 unsigned char c0, c1;
488 unsigned int cx;
489
490 switch (*ns_p) {
491 case PLIP_NB_BEGIN:
492 cx = nibble_timeout;
493 while (1) {
494 c0 = read_status(dev);
495 udelay(PLIP_DELAY_UNIT);
496 if ((c0 & 0x80) == 0) {
497 c1 = read_status(dev);
498 if (c0 == c1)
499 break;
500 }
501 if (--cx == 0)
502 return TIMEOUT;
503 }
504 *data_p = (c0 >> 3) & 0x0f;
505 write_data (dev, 0x10); /* send ACK */
506 *ns_p = PLIP_NB_1;
507 fallthrough;
508
509 case PLIP_NB_1:
510 cx = nibble_timeout;
511 while (1) {
512 c0 = read_status(dev);
513 udelay(PLIP_DELAY_UNIT);
514 if (c0 & 0x80) {
515 c1 = read_status(dev);
516 if (c0 == c1)
517 break;
518 }
519 if (--cx == 0)
520 return TIMEOUT;
521 }
522 *data_p |= (c0 << 1) & 0xf0;
523 write_data (dev, 0x00); /* send ACK */
524 *ns_p = PLIP_NB_BEGIN;
525 break;
526 case PLIP_NB_2:
527 break;
528 }
529 return OK;
530 }
531
532 /*
533 * Determine the packet's protocol ID. The rule here is that we
534 * assume 802.3 if the type field is short enough to be a length.
535 * This is normal practice and works for any 'now in use' protocol.
536 *
537 * PLIP is ethernet ish but the daddr might not be valid if unicast.
538 * PLIP fortunately has no bus architecture (its Point-to-point).
539 *
540 * We can't fix the daddr thing as that quirk (more bug) is embedded
541 * in far too many old systems not all even running Linux.
542 */
543
plip_type_trans(struct sk_buff * skb,struct net_device * dev)544 static __be16 plip_type_trans(struct sk_buff *skb, struct net_device *dev)
545 {
546 struct ethhdr *eth;
547 unsigned char *rawp;
548
549 skb_reset_mac_header(skb);
550 skb_pull(skb,dev->hard_header_len);
551 eth = eth_hdr(skb);
552
553 if(is_multicast_ether_addr(eth->h_dest))
554 {
555 if(ether_addr_equal_64bits(eth->h_dest, dev->broadcast))
556 skb->pkt_type=PACKET_BROADCAST;
557 else
558 skb->pkt_type=PACKET_MULTICAST;
559 }
560
561 /*
562 * This ALLMULTI check should be redundant by 1.4
563 * so don't forget to remove it.
564 */
565
566 if (ntohs(eth->h_proto) >= ETH_P_802_3_MIN)
567 return eth->h_proto;
568
569 rawp = skb->data;
570
571 /*
572 * This is a magic hack to spot IPX packets. Older Novell breaks
573 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
574 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
575 * won't work for fault tolerant netware but does for the rest.
576 */
577 if (*(unsigned short *)rawp == 0xFFFF)
578 return htons(ETH_P_802_3);
579
580 /*
581 * Real 802.2 LLC
582 */
583 return htons(ETH_P_802_2);
584 }
585
586 /* PLIP_RECEIVE_PACKET --- receive a packet */
587 static int
plip_receive_packet(struct net_device * dev,struct net_local * nl,struct plip_local * snd,struct plip_local * rcv)588 plip_receive_packet(struct net_device *dev, struct net_local *nl,
589 struct plip_local *snd, struct plip_local *rcv)
590 {
591 unsigned short nibble_timeout = nl->nibble;
592 unsigned char *lbuf;
593
594 switch (rcv->state) {
595 case PLIP_PK_TRIGGER:
596 DISABLE(dev->irq);
597 /* Don't need to synchronize irq, as we can safely ignore it */
598 disable_parport_interrupts (dev);
599 write_data (dev, 0x01); /* send ACK */
600 if (net_debug > 2)
601 printk(KERN_DEBUG "%s: receive start\n", dev->name);
602 rcv->state = PLIP_PK_LENGTH_LSB;
603 rcv->nibble = PLIP_NB_BEGIN;
604 fallthrough;
605
606 case PLIP_PK_LENGTH_LSB:
607 if (snd->state != PLIP_PK_DONE) {
608 if (plip_receive(nl->trigger, dev,
609 &rcv->nibble, &rcv->length.b.lsb)) {
610 /* collision, here dev->tbusy == 1 */
611 rcv->state = PLIP_PK_DONE;
612 nl->is_deferred = 1;
613 nl->connection = PLIP_CN_SEND;
614 schedule_delayed_work(&nl->deferred, 1);
615 enable_parport_interrupts (dev);
616 ENABLE(dev->irq);
617 return OK;
618 }
619 } else {
620 if (plip_receive(nibble_timeout, dev,
621 &rcv->nibble, &rcv->length.b.lsb))
622 return TIMEOUT;
623 }
624 rcv->state = PLIP_PK_LENGTH_MSB;
625 fallthrough;
626
627 case PLIP_PK_LENGTH_MSB:
628 if (plip_receive(nibble_timeout, dev,
629 &rcv->nibble, &rcv->length.b.msb))
630 return TIMEOUT;
631 if (rcv->length.h > dev->mtu + dev->hard_header_len ||
632 rcv->length.h < 8) {
633 printk(KERN_WARNING "%s: bogus packet size %d.\n", dev->name, rcv->length.h);
634 return ERROR;
635 }
636 /* Malloc up new buffer. */
637 rcv->skb = dev_alloc_skb(rcv->length.h + 2);
638 if (rcv->skb == NULL) {
639 printk(KERN_ERR "%s: Memory squeeze.\n", dev->name);
640 return ERROR;
641 }
642 skb_reserve(rcv->skb, 2); /* Align IP on 16 byte boundaries */
643 skb_put(rcv->skb,rcv->length.h);
644 rcv->skb->dev = dev;
645 rcv->state = PLIP_PK_DATA;
646 rcv->byte = 0;
647 rcv->checksum = 0;
648 fallthrough;
649
650 case PLIP_PK_DATA:
651 lbuf = rcv->skb->data;
652 do {
653 if (plip_receive(nibble_timeout, dev,
654 &rcv->nibble, &lbuf[rcv->byte]))
655 return TIMEOUT;
656 } while (++rcv->byte < rcv->length.h);
657 do {
658 rcv->checksum += lbuf[--rcv->byte];
659 } while (rcv->byte);
660 rcv->state = PLIP_PK_CHECKSUM;
661 fallthrough;
662
663 case PLIP_PK_CHECKSUM:
664 if (plip_receive(nibble_timeout, dev,
665 &rcv->nibble, &rcv->data))
666 return TIMEOUT;
667 if (rcv->data != rcv->checksum) {
668 dev->stats.rx_crc_errors++;
669 if (net_debug)
670 printk(KERN_DEBUG "%s: checksum error\n", dev->name);
671 return ERROR;
672 }
673 rcv->state = PLIP_PK_DONE;
674 fallthrough;
675
676 case PLIP_PK_DONE:
677 /* Inform the upper layer for the arrival of a packet. */
678 rcv->skb->protocol=plip_type_trans(rcv->skb, dev);
679 netif_rx(rcv->skb);
680 dev->stats.rx_bytes += rcv->length.h;
681 dev->stats.rx_packets++;
682 rcv->skb = NULL;
683 if (net_debug > 2)
684 printk(KERN_DEBUG "%s: receive end\n", dev->name);
685
686 /* Close the connection. */
687 write_data (dev, 0x00);
688 spin_lock_irq(&nl->lock);
689 if (snd->state != PLIP_PK_DONE) {
690 nl->connection = PLIP_CN_SEND;
691 spin_unlock_irq(&nl->lock);
692 schedule_work(&nl->immediate);
693 enable_parport_interrupts (dev);
694 ENABLE(dev->irq);
695 return OK;
696 } else {
697 nl->connection = PLIP_CN_NONE;
698 spin_unlock_irq(&nl->lock);
699 enable_parport_interrupts (dev);
700 ENABLE(dev->irq);
701 return OK;
702 }
703 }
704 return OK;
705 }
706
707 /* PLIP_SEND --- send a byte (two nibbles)
708 Returns OK on success, TIMEOUT when timeout */
709 static inline int
plip_send(unsigned short nibble_timeout,struct net_device * dev,enum plip_nibble_state * ns_p,unsigned char data)710 plip_send(unsigned short nibble_timeout, struct net_device *dev,
711 enum plip_nibble_state *ns_p, unsigned char data)
712 {
713 unsigned char c0;
714 unsigned int cx;
715
716 switch (*ns_p) {
717 case PLIP_NB_BEGIN:
718 write_data (dev, data & 0x0f);
719 *ns_p = PLIP_NB_1;
720 fallthrough;
721
722 case PLIP_NB_1:
723 write_data (dev, 0x10 | (data & 0x0f));
724 cx = nibble_timeout;
725 while (1) {
726 c0 = read_status(dev);
727 if ((c0 & 0x80) == 0)
728 break;
729 if (--cx == 0)
730 return TIMEOUT;
731 udelay(PLIP_DELAY_UNIT);
732 }
733 write_data (dev, 0x10 | (data >> 4));
734 *ns_p = PLIP_NB_2;
735 fallthrough;
736
737 case PLIP_NB_2:
738 write_data (dev, (data >> 4));
739 cx = nibble_timeout;
740 while (1) {
741 c0 = read_status(dev);
742 if (c0 & 0x80)
743 break;
744 if (--cx == 0)
745 return TIMEOUT;
746 udelay(PLIP_DELAY_UNIT);
747 }
748 *ns_p = PLIP_NB_BEGIN;
749 return OK;
750 }
751 return OK;
752 }
753
754 /* PLIP_SEND_PACKET --- send a packet */
755 static int
plip_send_packet(struct net_device * dev,struct net_local * nl,struct plip_local * snd,struct plip_local * rcv)756 plip_send_packet(struct net_device *dev, struct net_local *nl,
757 struct plip_local *snd, struct plip_local *rcv)
758 {
759 unsigned short nibble_timeout = nl->nibble;
760 unsigned char *lbuf;
761 unsigned char c0;
762 unsigned int cx;
763
764 if (snd->skb == NULL || (lbuf = snd->skb->data) == NULL) {
765 printk(KERN_DEBUG "%s: send skb lost\n", dev->name);
766 snd->state = PLIP_PK_DONE;
767 snd->skb = NULL;
768 return ERROR;
769 }
770
771 switch (snd->state) {
772 case PLIP_PK_TRIGGER:
773 if ((read_status(dev) & 0xf8) != 0x80)
774 return HS_TIMEOUT;
775
776 /* Trigger remote rx interrupt. */
777 write_data (dev, 0x08);
778 cx = nl->trigger;
779 while (1) {
780 udelay(PLIP_DELAY_UNIT);
781 spin_lock_irq(&nl->lock);
782 if (nl->connection == PLIP_CN_RECEIVE) {
783 spin_unlock_irq(&nl->lock);
784 /* Interrupted. */
785 dev->stats.collisions++;
786 return OK;
787 }
788 c0 = read_status(dev);
789 if (c0 & 0x08) {
790 spin_unlock_irq(&nl->lock);
791 DISABLE(dev->irq);
792 synchronize_irq(dev->irq);
793 if (nl->connection == PLIP_CN_RECEIVE) {
794 /* Interrupted.
795 We don't need to enable irq,
796 as it is soon disabled. */
797 /* Yes, we do. New variant of
798 {enable,disable}_irq *counts*
799 them. -- AV */
800 ENABLE(dev->irq);
801 dev->stats.collisions++;
802 return OK;
803 }
804 disable_parport_interrupts (dev);
805 if (net_debug > 2)
806 printk(KERN_DEBUG "%s: send start\n", dev->name);
807 snd->state = PLIP_PK_LENGTH_LSB;
808 snd->nibble = PLIP_NB_BEGIN;
809 nl->timeout_count = 0;
810 break;
811 }
812 spin_unlock_irq(&nl->lock);
813 if (--cx == 0) {
814 write_data (dev, 0x00);
815 return HS_TIMEOUT;
816 }
817 }
818 fallthrough;
819
820 case PLIP_PK_LENGTH_LSB:
821 if (plip_send(nibble_timeout, dev,
822 &snd->nibble, snd->length.b.lsb))
823 return TIMEOUT;
824 snd->state = PLIP_PK_LENGTH_MSB;
825 fallthrough;
826
827 case PLIP_PK_LENGTH_MSB:
828 if (plip_send(nibble_timeout, dev,
829 &snd->nibble, snd->length.b.msb))
830 return TIMEOUT;
831 snd->state = PLIP_PK_DATA;
832 snd->byte = 0;
833 snd->checksum = 0;
834 fallthrough;
835
836 case PLIP_PK_DATA:
837 do {
838 if (plip_send(nibble_timeout, dev,
839 &snd->nibble, lbuf[snd->byte]))
840 return TIMEOUT;
841 } while (++snd->byte < snd->length.h);
842 do {
843 snd->checksum += lbuf[--snd->byte];
844 } while (snd->byte);
845 snd->state = PLIP_PK_CHECKSUM;
846 fallthrough;
847
848 case PLIP_PK_CHECKSUM:
849 if (plip_send(nibble_timeout, dev,
850 &snd->nibble, snd->checksum))
851 return TIMEOUT;
852
853 dev->stats.tx_bytes += snd->skb->len;
854 dev_kfree_skb(snd->skb);
855 dev->stats.tx_packets++;
856 snd->state = PLIP_PK_DONE;
857 fallthrough;
858
859 case PLIP_PK_DONE:
860 /* Close the connection */
861 write_data (dev, 0x00);
862 snd->skb = NULL;
863 if (net_debug > 2)
864 printk(KERN_DEBUG "%s: send end\n", dev->name);
865 nl->connection = PLIP_CN_CLOSING;
866 nl->is_deferred = 1;
867 schedule_delayed_work(&nl->deferred, 1);
868 enable_parport_interrupts (dev);
869 ENABLE(dev->irq);
870 return OK;
871 }
872 return OK;
873 }
874
875 static int
plip_connection_close(struct net_device * dev,struct net_local * nl,struct plip_local * snd,struct plip_local * rcv)876 plip_connection_close(struct net_device *dev, struct net_local *nl,
877 struct plip_local *snd, struct plip_local *rcv)
878 {
879 spin_lock_irq(&nl->lock);
880 if (nl->connection == PLIP_CN_CLOSING) {
881 nl->connection = PLIP_CN_NONE;
882 netif_wake_queue (dev);
883 }
884 spin_unlock_irq(&nl->lock);
885 if (nl->should_relinquish) {
886 nl->should_relinquish = nl->port_owner = 0;
887 parport_release(nl->pardev);
888 }
889 return OK;
890 }
891
892 /* PLIP_ERROR --- wait till other end settled */
893 static int
plip_error(struct net_device * dev,struct net_local * nl,struct plip_local * snd,struct plip_local * rcv)894 plip_error(struct net_device *dev, struct net_local *nl,
895 struct plip_local *snd, struct plip_local *rcv)
896 {
897 unsigned char status;
898
899 status = read_status(dev);
900 if ((status & 0xf8) == 0x80) {
901 if (net_debug > 2)
902 printk(KERN_DEBUG "%s: reset interface.\n", dev->name);
903 nl->connection = PLIP_CN_NONE;
904 nl->should_relinquish = 0;
905 netif_start_queue (dev);
906 enable_parport_interrupts (dev);
907 ENABLE(dev->irq);
908 netif_wake_queue (dev);
909 } else {
910 nl->is_deferred = 1;
911 schedule_delayed_work(&nl->deferred, 1);
912 }
913
914 return OK;
915 }
916
917 /* Handle the parallel port interrupts. */
918 static void
plip_interrupt(void * dev_id)919 plip_interrupt(void *dev_id)
920 {
921 struct net_device *dev = dev_id;
922 struct net_local *nl;
923 struct plip_local *rcv;
924 unsigned char c0;
925 unsigned long flags;
926
927 nl = netdev_priv(dev);
928 rcv = &nl->rcv_data;
929
930 spin_lock_irqsave (&nl->lock, flags);
931
932 c0 = read_status(dev);
933 if ((c0 & 0xf8) != 0xc0) {
934 if ((dev->irq != -1) && (net_debug > 1))
935 printk(KERN_DEBUG "%s: spurious interrupt\n", dev->name);
936 spin_unlock_irqrestore (&nl->lock, flags);
937 return;
938 }
939
940 if (net_debug > 3)
941 printk(KERN_DEBUG "%s: interrupt.\n", dev->name);
942
943 switch (nl->connection) {
944 case PLIP_CN_CLOSING:
945 netif_wake_queue (dev);
946 fallthrough;
947 case PLIP_CN_NONE:
948 case PLIP_CN_SEND:
949 rcv->state = PLIP_PK_TRIGGER;
950 nl->connection = PLIP_CN_RECEIVE;
951 nl->timeout_count = 0;
952 schedule_work(&nl->immediate);
953 break;
954
955 case PLIP_CN_RECEIVE:
956 /* May occur because there is race condition
957 around test and set of dev->interrupt.
958 Ignore this interrupt. */
959 break;
960
961 case PLIP_CN_ERROR:
962 printk(KERN_ERR "%s: receive interrupt in error state\n", dev->name);
963 break;
964 }
965
966 spin_unlock_irqrestore(&nl->lock, flags);
967 }
968
969 static netdev_tx_t
plip_tx_packet(struct sk_buff * skb,struct net_device * dev)970 plip_tx_packet(struct sk_buff *skb, struct net_device *dev)
971 {
972 struct net_local *nl = netdev_priv(dev);
973 struct plip_local *snd = &nl->snd_data;
974
975 if (netif_queue_stopped(dev))
976 return NETDEV_TX_BUSY;
977
978 /* We may need to grab the bus */
979 if (!nl->port_owner) {
980 if (parport_claim(nl->pardev))
981 return NETDEV_TX_BUSY;
982 nl->port_owner = 1;
983 }
984
985 netif_stop_queue (dev);
986
987 if (skb->len > dev->mtu + dev->hard_header_len) {
988 printk(KERN_WARNING "%s: packet too big, %d.\n", dev->name, (int)skb->len);
989 netif_start_queue (dev);
990 return NETDEV_TX_BUSY;
991 }
992
993 if (net_debug > 2)
994 printk(KERN_DEBUG "%s: send request\n", dev->name);
995
996 spin_lock_irq(&nl->lock);
997 snd->skb = skb;
998 snd->length.h = skb->len;
999 snd->state = PLIP_PK_TRIGGER;
1000 if (nl->connection == PLIP_CN_NONE) {
1001 nl->connection = PLIP_CN_SEND;
1002 nl->timeout_count = 0;
1003 }
1004 schedule_work(&nl->immediate);
1005 spin_unlock_irq(&nl->lock);
1006
1007 return NETDEV_TX_OK;
1008 }
1009
1010 static void
plip_rewrite_address(const struct net_device * dev,struct ethhdr * eth)1011 plip_rewrite_address(const struct net_device *dev, struct ethhdr *eth)
1012 {
1013 const struct in_device *in_dev;
1014
1015 rcu_read_lock();
1016 in_dev = __in_dev_get_rcu(dev);
1017 if (in_dev) {
1018 /* Any address will do - we take the first */
1019 const struct in_ifaddr *ifa = rcu_dereference(in_dev->ifa_list);
1020 if (ifa) {
1021 memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
1022 memset(eth->h_dest, 0xfc, 2);
1023 memcpy(eth->h_dest+2, &ifa->ifa_address, 4);
1024 }
1025 }
1026 rcu_read_unlock();
1027 }
1028
1029 static int
plip_hard_header(struct sk_buff * skb,struct net_device * dev,unsigned short type,const void * daddr,const void * saddr,unsigned len)1030 plip_hard_header(struct sk_buff *skb, struct net_device *dev,
1031 unsigned short type, const void *daddr,
1032 const void *saddr, unsigned len)
1033 {
1034 int ret;
1035
1036 ret = eth_header(skb, dev, type, daddr, saddr, len);
1037 if (ret >= 0)
1038 plip_rewrite_address (dev, (struct ethhdr *)skb->data);
1039
1040 return ret;
1041 }
1042
plip_hard_header_cache(const struct neighbour * neigh,struct hh_cache * hh,__be16 type)1043 static int plip_hard_header_cache(const struct neighbour *neigh,
1044 struct hh_cache *hh, __be16 type)
1045 {
1046 int ret;
1047
1048 ret = eth_header_cache(neigh, hh, type);
1049 if (ret == 0) {
1050 struct ethhdr *eth;
1051
1052 eth = (struct ethhdr*)(((u8*)hh->hh_data) +
1053 HH_DATA_OFF(sizeof(*eth)));
1054 plip_rewrite_address (neigh->dev, eth);
1055 }
1056
1057 return ret;
1058 }
1059
1060 /* Open/initialize the board. This is called (in the current kernel)
1061 sometime after booting when the 'ifconfig' program is run.
1062
1063 This routine gets exclusive access to the parallel port by allocating
1064 its IRQ line.
1065 */
1066 static int
plip_open(struct net_device * dev)1067 plip_open(struct net_device *dev)
1068 {
1069 struct net_local *nl = netdev_priv(dev);
1070 struct in_device *in_dev;
1071
1072 /* Grab the port */
1073 if (!nl->port_owner) {
1074 if (parport_claim(nl->pardev)) return -EAGAIN;
1075 nl->port_owner = 1;
1076 }
1077
1078 nl->should_relinquish = 0;
1079
1080 /* Clear the data port. */
1081 write_data (dev, 0x00);
1082
1083 /* Enable rx interrupt. */
1084 enable_parport_interrupts (dev);
1085 if (dev->irq == -1)
1086 {
1087 atomic_set (&nl->kill_timer, 0);
1088 schedule_delayed_work(&nl->timer, 1);
1089 }
1090
1091 /* Initialize the state machine. */
1092 nl->rcv_data.state = nl->snd_data.state = PLIP_PK_DONE;
1093 nl->rcv_data.skb = nl->snd_data.skb = NULL;
1094 nl->connection = PLIP_CN_NONE;
1095 nl->is_deferred = 0;
1096
1097 /* Fill in the MAC-level header.
1098 We used to abuse dev->broadcast to store the point-to-point
1099 MAC address, but we no longer do it. Instead, we fetch the
1100 interface address whenever it is needed, which is cheap enough
1101 because we use the hh_cache. Actually, abusing dev->broadcast
1102 didn't work, because when using plip_open the point-to-point
1103 address isn't yet known.
1104 PLIP doesn't have a real MAC address, but we need it to be
1105 DOS compatible, and to properly support taps (otherwise,
1106 when the device address isn't identical to the address of a
1107 received frame, the kernel incorrectly drops it). */
1108
1109 in_dev=__in_dev_get_rtnl(dev);
1110 if (in_dev) {
1111 /* Any address will do - we take the first. We already
1112 have the first two bytes filled with 0xfc, from
1113 plip_init_dev(). */
1114 const struct in_ifaddr *ifa = rtnl_dereference(in_dev->ifa_list);
1115 if (ifa != NULL) {
1116 dev_addr_mod(dev, 2, &ifa->ifa_local, 4);
1117 }
1118 }
1119
1120 netif_start_queue (dev);
1121
1122 return 0;
1123 }
1124
1125 /* The inverse routine to plip_open (). */
1126 static int
plip_close(struct net_device * dev)1127 plip_close(struct net_device *dev)
1128 {
1129 struct net_local *nl = netdev_priv(dev);
1130 struct plip_local *snd = &nl->snd_data;
1131 struct plip_local *rcv = &nl->rcv_data;
1132
1133 netif_stop_queue (dev);
1134 DISABLE(dev->irq);
1135 synchronize_irq(dev->irq);
1136
1137 if (dev->irq == -1)
1138 {
1139 init_completion(&nl->killed_timer_cmp);
1140 atomic_set (&nl->kill_timer, 1);
1141 wait_for_completion(&nl->killed_timer_cmp);
1142 }
1143
1144 #ifdef NOTDEF
1145 outb(0x00, PAR_DATA(dev));
1146 #endif
1147 nl->is_deferred = 0;
1148 nl->connection = PLIP_CN_NONE;
1149 if (nl->port_owner) {
1150 parport_release(nl->pardev);
1151 nl->port_owner = 0;
1152 }
1153
1154 snd->state = PLIP_PK_DONE;
1155 if (snd->skb) {
1156 dev_kfree_skb(snd->skb);
1157 snd->skb = NULL;
1158 }
1159 rcv->state = PLIP_PK_DONE;
1160 if (rcv->skb) {
1161 kfree_skb(rcv->skb);
1162 rcv->skb = NULL;
1163 }
1164
1165 #ifdef NOTDEF
1166 /* Reset. */
1167 outb(0x00, PAR_CONTROL(dev));
1168 #endif
1169 return 0;
1170 }
1171
1172 static int
plip_preempt(void * handle)1173 plip_preempt(void *handle)
1174 {
1175 struct net_device *dev = (struct net_device *)handle;
1176 struct net_local *nl = netdev_priv(dev);
1177
1178 /* Stand our ground if a datagram is on the wire */
1179 if (nl->connection != PLIP_CN_NONE) {
1180 nl->should_relinquish = 1;
1181 return 1;
1182 }
1183
1184 nl->port_owner = 0; /* Remember that we released the bus */
1185 return 0;
1186 }
1187
1188 static void
plip_wakeup(void * handle)1189 plip_wakeup(void *handle)
1190 {
1191 struct net_device *dev = (struct net_device *)handle;
1192 struct net_local *nl = netdev_priv(dev);
1193
1194 if (nl->port_owner) {
1195 /* Why are we being woken up? */
1196 printk(KERN_DEBUG "%s: why am I being woken up?\n", dev->name);
1197 if (!parport_claim(nl->pardev))
1198 /* bus_owner is already set (but why?) */
1199 printk(KERN_DEBUG "%s: I'm broken.\n", dev->name);
1200 else
1201 return;
1202 }
1203
1204 if (!(dev->flags & IFF_UP))
1205 /* Don't need the port when the interface is down */
1206 return;
1207
1208 if (!parport_claim(nl->pardev)) {
1209 nl->port_owner = 1;
1210 /* Clear the data port. */
1211 write_data (dev, 0x00);
1212 }
1213 }
1214
1215 static int
plip_siocdevprivate(struct net_device * dev,struct ifreq * rq,void __user * data,int cmd)1216 plip_siocdevprivate(struct net_device *dev, struct ifreq *rq,
1217 void __user *data, int cmd)
1218 {
1219 struct net_local *nl = netdev_priv(dev);
1220 struct plipconf *pc = (struct plipconf *) &rq->ifr_ifru;
1221
1222 if (cmd != SIOCDEVPLIP)
1223 return -EOPNOTSUPP;
1224
1225 if (in_compat_syscall())
1226 return -EOPNOTSUPP;
1227
1228 switch(pc->pcmd) {
1229 case PLIP_GET_TIMEOUT:
1230 pc->trigger = nl->trigger;
1231 pc->nibble = nl->nibble;
1232 break;
1233 case PLIP_SET_TIMEOUT:
1234 if(!capable(CAP_NET_ADMIN))
1235 return -EPERM;
1236 nl->trigger = pc->trigger;
1237 nl->nibble = pc->nibble;
1238 break;
1239 default:
1240 return -EOPNOTSUPP;
1241 }
1242 return 0;
1243 }
1244
1245 static int parport[PLIP_MAX] = { [0 ... PLIP_MAX-1] = -1 };
1246 static int timid;
1247
1248 module_param_array(parport, int, NULL, 0);
1249 module_param(timid, int, 0);
1250 MODULE_PARM_DESC(parport, "List of parport device numbers to use by plip");
1251
1252 static struct net_device *dev_plip[PLIP_MAX] = { NULL, };
1253
1254 static inline int
plip_searchfor(int list[],int a)1255 plip_searchfor(int list[], int a)
1256 {
1257 int i;
1258 for (i = 0; i < PLIP_MAX && list[i] != -1; i++) {
1259 if (list[i] == a) return 1;
1260 }
1261 return 0;
1262 }
1263
1264 /* plip_attach() is called (by the parport code) when a port is
1265 * available to use. */
plip_attach(struct parport * port)1266 static void plip_attach (struct parport *port)
1267 {
1268 static int unit;
1269 struct net_device *dev;
1270 struct net_local *nl;
1271 char name[IFNAMSIZ];
1272 struct pardev_cb plip_cb;
1273
1274 if ((parport[0] == -1 && (!timid || !port->devices)) ||
1275 plip_searchfor(parport, port->number)) {
1276 if (unit == PLIP_MAX) {
1277 printk(KERN_ERR "plip: too many devices\n");
1278 return;
1279 }
1280
1281 sprintf(name, "plip%d", unit);
1282 dev = alloc_etherdev(sizeof(struct net_local));
1283 if (!dev)
1284 return;
1285
1286 strcpy(dev->name, name);
1287
1288 dev->irq = port->irq;
1289 dev->base_addr = port->base;
1290 if (port->irq == -1) {
1291 printk(KERN_INFO "plip: %s has no IRQ. Using IRQ-less mode,"
1292 "which is fairly inefficient!\n", port->name);
1293 }
1294
1295 nl = netdev_priv(dev);
1296 nl->dev = dev;
1297
1298 memset(&plip_cb, 0, sizeof(plip_cb));
1299 plip_cb.private = dev;
1300 plip_cb.preempt = plip_preempt;
1301 plip_cb.wakeup = plip_wakeup;
1302 plip_cb.irq_func = plip_interrupt;
1303
1304 nl->pardev = parport_register_dev_model(port, dev->name,
1305 &plip_cb, unit);
1306
1307 if (!nl->pardev) {
1308 printk(KERN_ERR "%s: parport_register failed\n", name);
1309 goto err_free_dev;
1310 }
1311
1312 plip_init_netdev(dev);
1313
1314 if (register_netdev(dev)) {
1315 printk(KERN_ERR "%s: network register failed\n", name);
1316 goto err_parport_unregister;
1317 }
1318
1319 printk(KERN_INFO "%s", version);
1320 if (dev->irq != -1)
1321 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1322 "using IRQ %d.\n",
1323 dev->name, dev->base_addr, dev->irq);
1324 else
1325 printk(KERN_INFO "%s: Parallel port at %#3lx, "
1326 "not using IRQ.\n",
1327 dev->name, dev->base_addr);
1328 dev_plip[unit++] = dev;
1329 }
1330 return;
1331
1332 err_parport_unregister:
1333 parport_unregister_device(nl->pardev);
1334 err_free_dev:
1335 free_netdev(dev);
1336 }
1337
1338 /* plip_detach() is called (by the parport code) when a port is
1339 * no longer available to use. */
plip_detach(struct parport * port)1340 static void plip_detach (struct parport *port)
1341 {
1342 /* Nothing to do */
1343 }
1344
plip_probe(struct pardevice * par_dev)1345 static int plip_probe(struct pardevice *par_dev)
1346 {
1347 struct device_driver *drv = par_dev->dev.driver;
1348 int len = strlen(drv->name);
1349
1350 if (strncmp(par_dev->name, drv->name, len))
1351 return -ENODEV;
1352
1353 return 0;
1354 }
1355
1356 static struct parport_driver plip_driver = {
1357 .name = "plip",
1358 .probe = plip_probe,
1359 .match_port = plip_attach,
1360 .detach = plip_detach,
1361 };
1362
plip_cleanup_module(void)1363 static void __exit plip_cleanup_module (void)
1364 {
1365 struct net_device *dev;
1366 int i;
1367
1368 for (i=0; i < PLIP_MAX; i++) {
1369 if ((dev = dev_plip[i])) {
1370 struct net_local *nl = netdev_priv(dev);
1371 unregister_netdev(dev);
1372 if (nl->port_owner)
1373 parport_release(nl->pardev);
1374 parport_unregister_device(nl->pardev);
1375 free_netdev(dev);
1376 dev_plip[i] = NULL;
1377 }
1378 }
1379
1380 parport_unregister_driver(&plip_driver);
1381 }
1382
1383 #ifndef MODULE
1384
1385 static int parport_ptr;
1386
plip_setup(char * str)1387 static int __init plip_setup(char *str)
1388 {
1389 int ints[4];
1390
1391 str = get_options(str, ARRAY_SIZE(ints), ints);
1392
1393 /* Ugh. */
1394 if (!strncmp(str, "parport", 7)) {
1395 int n = simple_strtoul(str+7, NULL, 10);
1396 if (parport_ptr < PLIP_MAX)
1397 parport[parport_ptr++] = n;
1398 else
1399 printk(KERN_INFO "plip: too many ports, %s ignored.\n",
1400 str);
1401 } else if (!strcmp(str, "timid")) {
1402 timid = 1;
1403 } else {
1404 if (ints[0] == 0 || ints[1] == 0) {
1405 /* disable driver on "plip=" or "plip=0" */
1406 parport[0] = -2;
1407 } else {
1408 printk(KERN_WARNING "warning: 'plip=0x%x' ignored\n",
1409 ints[1]);
1410 }
1411 }
1412 return 1;
1413 }
1414
1415 __setup("plip=", plip_setup);
1416
1417 #endif /* !MODULE */
1418
plip_init(void)1419 static int __init plip_init (void)
1420 {
1421 if (parport[0] == -2)
1422 return 0;
1423
1424 if (parport[0] != -1 && timid) {
1425 printk(KERN_WARNING "plip: warning, ignoring `timid' since specific ports given.\n");
1426 timid = 0;
1427 }
1428
1429 if (parport_register_driver (&plip_driver)) {
1430 printk (KERN_WARNING "plip: couldn't register driver\n");
1431 return 1;
1432 }
1433
1434 return 0;
1435 }
1436
1437 module_init(plip_init);
1438 module_exit(plip_cleanup_module);
1439 MODULE_DESCRIPTION("PLIP (parallel port) network module");
1440 MODULE_LICENSE("GPL");
1441