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Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[linux.git] / drivers / parport / ieee1284_ops.c
CommitLineData
1da177e4
LT		 1/* IEEE-1284 operations for parport.
2 *
3 * This file is for generic IEEE 1284 operations. The idea is that
4 * they are used by the low-level drivers. If they have a special way
5 * of doing something, they can provide their own routines (and put
6 * the function pointers in port->ops); if not, they can just use these
7 * as a fallback.
8 *
9 * Note: Make no assumptions about hardware or architecture in this file!
10 *
11 * Author: Tim Waugh <[email protected]>
12 * Fixed AUTOFD polarity in ecp_forward_to_reverse(). Fred Barnes, 1999
13 * Software emulated EPP fixes, Fred Barnes, 04/2001.
14 */
15
16
1da177e4
LT		 17#include <linux/module.h>
18#include <linux/parport.h>
19#include <linux/delay.h>
174cd4b1 20#include <linux/sched/signal.h>
7c0f6ba6 21#include <linux/uaccess.h>
1da177e4
LT		 22
23#undef DEBUG /* undef me for production */
24
25#ifdef CONFIG_LP_CONSOLE
26#undef DEBUG /* Don't want a garbled console */
27#endif
28
29#ifdef DEBUG
30#define DPRINTK(stuff...) printk (stuff)
31#else
32#define DPRINTK(stuff...)
33#endif
34
35/*** *
36 * One-way data transfer functions. *
37 * ***/
38
39/* Compatibility mode. */
40size_t parport_ieee1284_write_compat (struct parport *port,
41 const void *buffer, size_t len,
42 int flags)
43{
44 int no_irq = 1;
45 ssize_t count = 0;
46 const unsigned char *addr = buffer;
47 unsigned char byte;
48 struct pardevice *dev = port->physport->cad;
49 unsigned char ctl = (PARPORT_CONTROL_SELECT
50 | PARPORT_CONTROL_INIT);
51
52 if (port->irq != PARPORT_IRQ_NONE) {
53 parport_enable_irq (port);
54 no_irq = 0;
55 }
56
57 port->physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
58 parport_write_control (port, ctl);
59 parport_data_forward (port);
60 while (count < len) {
61 unsigned long expire = jiffies + dev->timeout;
7b4ccf8d 62 long wait = msecs_to_jiffies(10);
1da177e4
LT		 63 unsigned char mask = (PARPORT_STATUS_ERROR
64 | PARPORT_STATUS_BUSY);
65 unsigned char val = (PARPORT_STATUS_ERROR
66 | PARPORT_STATUS_BUSY);
67
68 /* Wait until the peripheral's ready */
69 do {
70 /* Is the peripheral ready yet? */
71 if (!parport_wait_peripheral (port, mask, val))
72 /* Skip the loop */
73 goto ready;
74
75 /* Is the peripheral upset? */
76 if ((parport_read_status (port) &
77 (PARPORT_STATUS_PAPEROUT |
78 PARPORT_STATUS_SELECT |
79 PARPORT_STATUS_ERROR))
80 != (PARPORT_STATUS_SELECT |
81 PARPORT_STATUS_ERROR))
82 /* If nFault is asserted (i.e. no
83 * error) and PAPEROUT and SELECT are
84 * just red herrings, give the driver
85 * a chance to check it's happy with
86 * that before continuing. */
87 goto stop;
88
89 /* Have we run out of time? */
90 if (!time_before (jiffies, expire))
91 break;
92
93 /* Yield the port for a while. If this is the
94 first time around the loop, don't let go of
95 the port. This way, we find out if we have
96 our interrupt handler called. */
97 if (count && no_irq) {
98 parport_release (dev);
7b4ccf8d 99 schedule_timeout_interruptible(wait);
1da177e4
LT		 100 parport_claim_or_block (dev);
101 }
102 else
103 /* We must have the device claimed here */
104 parport_wait_event (port, wait);
105
106 /* Is there a signal pending? */
107 if (signal_pending (current))
108 break;
109
110 /* Wait longer next time. */
111 wait *= 2;
112 } while (time_before (jiffies, expire));
113
114 if (signal_pending (current))
115 break;
116
117 DPRINTK (KERN_DEBUG "%s: Timed out\n", port->name);
118 break;
119
120 ready:
121 /* Write the character to the data lines. */
122 byte = *addr++;
123 parport_write_data (port, byte);
124 udelay (1);
125
126 /* Pulse strobe. */
127 parport_write_control (port, ctl | PARPORT_CONTROL_STROBE);
128 udelay (1); /* strobe */
129
130 parport_write_control (port, ctl);
131 udelay (1); /* hold */
132
133 /* Assume the peripheral received it. */
134 count++;
135
136 /* Let another process run if it needs to. */
137 if (time_before (jiffies, expire))
138 if (!parport_yield_blocking (dev)
139 && need_resched())
140 schedule ();
141 }
142 stop:
143 port->physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
144
145 return count;
146}
147
148/* Nibble mode. */
149size_t parport_ieee1284_read_nibble (struct parport *port,
150 void *buffer, size_t len,
151 int flags)
152{
153#ifndef CONFIG_PARPORT_1284
154 return 0;
155#else
156 unsigned char *buf = buffer;
157 int i;
158 unsigned char byte = 0;
159
160 len *= 2; /* in nibbles */
161 for (i=0; i < len; i++) {
162 unsigned char nibble;
163
164 /* Does the error line indicate end of data? */
165 if (((i & 1) == 0) &&
166 (parport_read_status(port) & PARPORT_STATUS_ERROR)) {
742ec650 167 goto end_of_data;
1da177e4
LT		 168 }
169
170 /* Event 7: Set nAutoFd low. */
171 parport_frob_control (port,
172 PARPORT_CONTROL_AUTOFD,
173 PARPORT_CONTROL_AUTOFD);
174
175 /* Event 9: nAck goes low. */
176 port->ieee1284.phase = IEEE1284_PH_REV_DATA;
177 if (parport_wait_peripheral (port,
178 PARPORT_STATUS_ACK, 0)) {
179 /* Timeout -- no more data? */
180 DPRINTK (KERN_DEBUG
181 "%s: Nibble timeout at event 9 (%d bytes)\n",
182 port->name, i/2);
183 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
184 break;
185 }
186
187
188 /* Read a nibble. */
189 nibble = parport_read_status (port) >> 3;
190 nibble &= ~8;
191 if ((nibble & 0x10) == 0)
192 nibble |= 8;
193 nibble &= 0xf;
194
195 /* Event 10: Set nAutoFd high. */
196 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
197
198 /* Event 11: nAck goes high. */
199 if (parport_wait_peripheral (port,
200 PARPORT_STATUS_ACK,
201 PARPORT_STATUS_ACK)) {
202 /* Timeout -- no more data? */
203 DPRINTK (KERN_DEBUG
204 "%s: Nibble timeout at event 11\n",
205 port->name);
206 break;
207 }
208
209 if (i & 1) {
210 /* Second nibble */
211 byte |= nibble << 4;
212 *buf++ = byte;
213 } else
214 byte = nibble;
215 }
216
1da177e4
LT		 217 if (i == len) {
218 /* Read the last nibble without checking data avail. */
742ec650
MK		 219 if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
220 end_of_data:
221 DPRINTK (KERN_DEBUG
222 "%s: No more nibble data (%d bytes)\n",
223 port->name, i/2);
224
225 /* Go to reverse idle phase. */
226 parport_frob_control (port,
227 PARPORT_CONTROL_AUTOFD,
228 PARPORT_CONTROL_AUTOFD);
229 port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
230 }
1da177e4 231 else
742ec650 232 port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
1da177e4
LT		 233 }
234
742ec650 235 return i/2;
1da177e4
LT		 236#endif /* IEEE1284 support */
237}
238
239/* Byte mode. */
240size_t parport_ieee1284_read_byte (struct parport *port,
241 void *buffer, size_t len,
242 int flags)
243{
244#ifndef CONFIG_PARPORT_1284
245 return 0;
246#else
247 unsigned char *buf = buffer;
248 ssize_t count = 0;
249
250 for (count = 0; count < len; count++) {
251 unsigned char byte;
252
253 /* Data available? */
254 if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
742ec650 255 goto end_of_data;
1da177e4
LT		 256 }
257
258 /* Event 14: Place data bus in high impedance state. */
259 parport_data_reverse (port);
260
261 /* Event 7: Set nAutoFd low. */
262 parport_frob_control (port,
263 PARPORT_CONTROL_AUTOFD,
264 PARPORT_CONTROL_AUTOFD);
265
266 /* Event 9: nAck goes low. */
267 port->physport->ieee1284.phase = IEEE1284_PH_REV_DATA;
268 if (parport_wait_peripheral (port,
269 PARPORT_STATUS_ACK,
270 0)) {
271 /* Timeout -- no more data? */
272 parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
273 0);
274 DPRINTK (KERN_DEBUG "%s: Byte timeout at event 9\n",
275 port->name);
276 break;
277 }
278
279 byte = parport_read_data (port);
280 *buf++ = byte;
281
282 /* Event 10: Set nAutoFd high */
283 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
284
285 /* Event 11: nAck goes high. */
286 if (parport_wait_peripheral (port,
287 PARPORT_STATUS_ACK,
288 PARPORT_STATUS_ACK)) {
289 /* Timeout -- no more data? */
290 DPRINTK (KERN_DEBUG "%s: Byte timeout at event 11\n",
291 port->name);
292 break;
293 }
294
295 /* Event 16: Set nStrobe low. */
296 parport_frob_control (port,
297 PARPORT_CONTROL_STROBE,
298 PARPORT_CONTROL_STROBE);
299 udelay (5);
300
301 /* Event 17: Set nStrobe high. */
302 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
303 }
304
305 if (count == len) {
306 /* Read the last byte without checking data avail. */
742ec650
MK		 307 if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
308 end_of_data:
309 DPRINTK (KERN_DEBUG
5b5e0928 310 "%s: No more byte data (%zd bytes)\n",
742ec650
MK		 311 port->name, count);
312
313 /* Go to reverse idle phase. */
314 parport_frob_control (port,
315 PARPORT_CONTROL_AUTOFD,
316 PARPORT_CONTROL_AUTOFD);
317 port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
318 }
1da177e4 319 else
742ec650 320 port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
1da177e4
LT		 321 }
322
323 return count;
324#endif /* IEEE1284 support */
325}
326
327/*** *
328 * ECP Functions. *
329 * ***/
330
331#ifdef CONFIG_PARPORT_1284
332
333static inline
334int ecp_forward_to_reverse (struct parport *port)
335{
336 int retval;
337
338 /* Event 38: Set nAutoFd low */
339 parport_frob_control (port,
340 PARPORT_CONTROL_AUTOFD,
341 PARPORT_CONTROL_AUTOFD);
342 parport_data_reverse (port);
343 udelay (5);
344
345 /* Event 39: Set nInit low to initiate bus reversal */
346 parport_frob_control (port,
347 PARPORT_CONTROL_INIT,
348 0);
349
350 /* Event 40: PError goes low */
351 retval = parport_wait_peripheral (port,
352 PARPORT_STATUS_PAPEROUT, 0);
353
354 if (!retval) {
355 DPRINTK (KERN_DEBUG "%s: ECP direction: reverse\n",
356 port->name);
357 port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
358 } else {
359 DPRINTK (KERN_DEBUG "%s: ECP direction: failed to reverse\n",
360 port->name);
361 port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
362 }
363
364 return retval;
365}
366
367static inline
368int ecp_reverse_to_forward (struct parport *port)
369{
370 int retval;
371
372 /* Event 47: Set nInit high */
373 parport_frob_control (port,
374 PARPORT_CONTROL_INIT
375 | PARPORT_CONTROL_AUTOFD,
376 PARPORT_CONTROL_INIT
377 | PARPORT_CONTROL_AUTOFD);
378
379 /* Event 49: PError goes high */
380 retval = parport_wait_peripheral (port,
381 PARPORT_STATUS_PAPEROUT,
382 PARPORT_STATUS_PAPEROUT);
383
384 if (!retval) {
385 parport_data_forward (port);
386 DPRINTK (KERN_DEBUG "%s: ECP direction: forward\n",
387 port->name);
388 port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
389 } else {
390 DPRINTK (KERN_DEBUG
391 "%s: ECP direction: failed to switch forward\n",
392 port->name);
393 port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
394 }
395
396
397 return retval;
398}
399
400#endif /* IEEE1284 support */
401
402/* ECP mode, forward channel, data. */
403size_t parport_ieee1284_ecp_write_data (struct parport *port,
404 const void *buffer, size_t len,
405 int flags)
406{
407#ifndef CONFIG_PARPORT_1284
408 return 0;
409#else
410 const unsigned char *buf = buffer;
411 size_t written;
412 int retry;
413
414 port = port->physport;
415
416 if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
417 if (ecp_reverse_to_forward (port))
418 return 0;
419
420 port->ieee1284.phase = IEEE1284_PH_FWD_DATA;
421
422 /* HostAck high (data, not command) */
423 parport_frob_control (port,
424 PARPORT_CONTROL_AUTOFD
425 | PARPORT_CONTROL_STROBE
426 | PARPORT_CONTROL_INIT,
427 PARPORT_CONTROL_INIT);
428 for (written = 0; written < len; written++, buf++) {
429 unsigned long expire = jiffies + port->cad->timeout;
430 unsigned char byte;
431
432 byte = *buf;
433 try_again:
434 parport_write_data (port, byte);
435 parport_frob_control (port, PARPORT_CONTROL_STROBE,
436 PARPORT_CONTROL_STROBE);
437 udelay (5);
438 for (retry = 0; retry < 100; retry++) {
439 if (!parport_wait_peripheral (port,
440 PARPORT_STATUS_BUSY, 0))
441 goto success;
442
443 if (signal_pending (current)) {
444 parport_frob_control (port,
445 PARPORT_CONTROL_STROBE,
446 0);
447 break;
448 }
449 }
450
451 /* Time for Host Transfer Recovery (page 41 of IEEE1284) */
452 DPRINTK (KERN_DEBUG "%s: ECP transfer stalled!\n", port->name);
453
454 parport_frob_control (port, PARPORT_CONTROL_INIT,
455 PARPORT_CONTROL_INIT);
456 udelay (50);
457 if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
458 /* It's buggered. */
459 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
460 break;
461 }
462
463 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
464 udelay (50);
465 if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
466 break;
467
468 DPRINTK (KERN_DEBUG "%s: Host transfer recovered\n",
469 port->name);
470
471 if (time_after_eq (jiffies, expire)) break;
472 goto try_again;
473 success:
474 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
475 udelay (5);
476 if (parport_wait_peripheral (port,
477 PARPORT_STATUS_BUSY,
478 PARPORT_STATUS_BUSY))
479 /* Peripheral hasn't accepted the data. */
480 break;
481 }
482
483 port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
484
485 return written;
486#endif /* IEEE1284 support */
487}
488
489/* ECP mode, reverse channel, data. */
490size_t parport_ieee1284_ecp_read_data (struct parport *port,
491 void *buffer, size_t len, int flags)
492{
493#ifndef CONFIG_PARPORT_1284
494 return 0;
495#else
496 struct pardevice *dev = port->cad;
497 unsigned char *buf = buffer;
498 int rle_count = 0; /* shut gcc up */
499 unsigned char ctl;
500 int rle = 0;
501 ssize_t count = 0;
502
503 port = port->physport;
504
505 if (port->ieee1284.phase != IEEE1284_PH_REV_IDLE)
506 if (ecp_forward_to_reverse (port))
507 return 0;
508
509 port->ieee1284.phase = IEEE1284_PH_REV_DATA;
510
511 /* Set HostAck low to start accepting data. */
512 ctl = parport_read_control (port);
513 ctl &= ~(PARPORT_CONTROL_STROBE | PARPORT_CONTROL_INIT |
514 PARPORT_CONTROL_AUTOFD);
515 parport_write_control (port,
516 ctl | PARPORT_CONTROL_AUTOFD);
517 while (count < len) {
518 unsigned long expire = jiffies + dev->timeout;
519 unsigned char byte;
520 int command;
521
522 /* Event 43: Peripheral sets nAck low. It can take as
523 long as it wants. */
524 while (parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0)) {
525 /* The peripheral hasn't given us data in
526 35ms. If we have data to give back to the
527 caller, do it now. */
528 if (count)
529 goto out;
530
531 /* If we've used up all the time we were allowed,
532 give up altogether. */
533 if (!time_before (jiffies, expire))
534 goto out;
535
536 /* Yield the port for a while. */
537 if (count && dev->port->irq != PARPORT_IRQ_NONE) {
538 parport_release (dev);
7b4ccf8d 539 schedule_timeout_interruptible(msecs_to_jiffies(40));
1da177e4
LT		 540 parport_claim_or_block (dev);
541 }
542 else
543 /* We must have the device claimed here. */
7b4ccf8d 544 parport_wait_event (port, msecs_to_jiffies(40));
1da177e4
LT		 545
546 /* Is there a signal pending? */
547 if (signal_pending (current))
548 goto out;
549 }
550
551 /* Is this a command? */
552 if (rle)
553 /* The last byte was a run-length count, so
554 this can't be as well. */
555 command = 0;
556 else
557 command = (parport_read_status (port) &
558 PARPORT_STATUS_BUSY) ? 1 : 0;
559
560 /* Read the data. */
561 byte = parport_read_data (port);
562
563 /* If this is a channel command, rather than an RLE
564 command or a normal data byte, don't accept it. */
565 if (command) {
566 if (byte & 0x80) {
567 DPRINTK (KERN_DEBUG "%s: stopping short at "
568 "channel command (%02x)\n",
569 port->name, byte);
570 goto out;
571 }
572 else if (port->ieee1284.mode != IEEE1284_MODE_ECPRLE)
573 DPRINTK (KERN_DEBUG "%s: device illegally "
574 "using RLE; accepting anyway\n",
575 port->name);
576
577 rle_count = byte + 1;
578
579 /* Are we allowed to read that many bytes? */
580 if (rle_count > (len - count)) {
581 DPRINTK (KERN_DEBUG "%s: leaving %d RLE bytes "
582 "for next time\n", port->name,
583 rle_count);
584 break;
585 }
586
587 rle = 1;
588 }
589
590 /* Event 44: Set HostAck high, acknowledging handshake. */
591 parport_write_control (port, ctl);
592
593 /* Event 45: The peripheral has 35ms to set nAck high. */
594 if (parport_wait_peripheral (port, PARPORT_STATUS_ACK,
595 PARPORT_STATUS_ACK)) {
596 /* It's gone wrong. Return what data we have
597 to the caller. */
598 DPRINTK (KERN_DEBUG "ECP read timed out at 45\n");
599
600 if (command)
601 printk (KERN_WARNING
602 "%s: command ignored (%02x)\n",
603 port->name, byte);
604
605 break;
606 }
607
608 /* Event 46: Set HostAck low and accept the data. */
609 parport_write_control (port,
610 ctl | PARPORT_CONTROL_AUTOFD);
611
612 /* If we just read a run-length count, fetch the data. */
613 if (command)
614 continue;
615
616 /* If this is the byte after a run-length count, decompress. */
617 if (rle) {
618 rle = 0;
619 memset (buf, byte, rle_count);
620 buf += rle_count;
621 count += rle_count;
622 DPRINTK (KERN_DEBUG "%s: decompressed to %d bytes\n",
623 port->name, rle_count);
624 } else {
625 /* Normal data byte. */
626 *buf = byte;
627 buf++, count++;
628 }
629 }
630
631 out:
632 port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
633 return count;
634#endif /* IEEE1284 support */
635}
636
637/* ECP mode, forward channel, commands. */
638size_t parport_ieee1284_ecp_write_addr (struct parport *port,
639 const void *buffer, size_t len,
640 int flags)
641{
642#ifndef CONFIG_PARPORT_1284
643 return 0;
644#else
645 const unsigned char *buf = buffer;
646 size_t written;
647 int retry;
648
649 port = port->physport;
650
651 if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
652 if (ecp_reverse_to_forward (port))
653 return 0;
654
655 port->ieee1284.phase = IEEE1284_PH_FWD_DATA;
656
657 /* HostAck low (command, not data) */
658 parport_frob_control (port,
659 PARPORT_CONTROL_AUTOFD
660 | PARPORT_CONTROL_STROBE
661 | PARPORT_CONTROL_INIT,
662 PARPORT_CONTROL_AUTOFD
663 | PARPORT_CONTROL_INIT);
664 for (written = 0; written < len; written++, buf++) {
665 unsigned long expire = jiffies + port->cad->timeout;
666 unsigned char byte;
667
668 byte = *buf;
669 try_again:
670 parport_write_data (port, byte);
671 parport_frob_control (port, PARPORT_CONTROL_STROBE,
672 PARPORT_CONTROL_STROBE);
673 udelay (5);
674 for (retry = 0; retry < 100; retry++) {
675 if (!parport_wait_peripheral (port,
676 PARPORT_STATUS_BUSY, 0))
677 goto success;
678
679 if (signal_pending (current)) {
680 parport_frob_control (port,
681 PARPORT_CONTROL_STROBE,
682 0);
683 break;
684 }
685 }
686
687 /* Time for Host Transfer Recovery (page 41 of IEEE1284) */
688 DPRINTK (KERN_DEBUG "%s: ECP transfer stalled!\n", port->name);
689
690 parport_frob_control (port, PARPORT_CONTROL_INIT,
691 PARPORT_CONTROL_INIT);
692 udelay (50);
693 if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
694 /* It's buggered. */
695 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
696 break;
697 }
698
699 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
700 udelay (50);
701 if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
702 break;
703
704 DPRINTK (KERN_DEBUG "%s: Host transfer recovered\n",
705 port->name);
706
707 if (time_after_eq (jiffies, expire)) break;
708 goto try_again;
709 success:
710 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
711 udelay (5);
712 if (parport_wait_peripheral (port,
713 PARPORT_STATUS_BUSY,
714 PARPORT_STATUS_BUSY))
715 /* Peripheral hasn't accepted the data. */
716 break;
717 }
718
719 port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
720
721 return written;
722#endif /* IEEE1284 support */
723}
724
725/*** *
726 * EPP functions. *
727 * ***/
728
729/* EPP mode, forward channel, data. */
730size_t parport_ieee1284_epp_write_data (struct parport *port,
731 const void *buffer, size_t len,
732 int flags)
733{
734 unsigned char *bp = (unsigned char *) buffer;
735 size_t ret = 0;
736
737 /* set EPP idle state (just to make sure) with strobe low */
738 parport_frob_control (port,
739 PARPORT_CONTROL_STROBE |
740 PARPORT_CONTROL_AUTOFD |
741 PARPORT_CONTROL_SELECT |
742 PARPORT_CONTROL_INIT,
743 PARPORT_CONTROL_STROBE |
744 PARPORT_CONTROL_INIT);
745 port->ops->data_forward (port);
746 for (; len > 0; len--, bp++) {
747 /* Event 62: Write data and set autofd low */
748 parport_write_data (port, *bp);
749 parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
750 PARPORT_CONTROL_AUTOFD);
751
752 /* Event 58: wait for busy (nWait) to go high */
753 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
754 break;
755
756 /* Event 63: set nAutoFd (nDStrb) high */
757 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
758
759 /* Event 60: wait for busy (nWait) to go low */
760 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
761 PARPORT_STATUS_BUSY, 5))
762 break;
763
764 ret++;
765 }
766
767 /* Event 61: set strobe (nWrite) high */
768 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
769
770 return ret;
771}
772
773/* EPP mode, reverse channel, data. */
774size_t parport_ieee1284_epp_read_data (struct parport *port,
775 void *buffer, size_t len,
776 int flags)
777{
778 unsigned char *bp = (unsigned char *) buffer;
779 unsigned ret = 0;
780
781 /* set EPP idle state (just to make sure) with strobe high */
782 parport_frob_control (port,
783 PARPORT_CONTROL_STROBE |
784 PARPORT_CONTROL_AUTOFD |
785 PARPORT_CONTROL_SELECT |
786 PARPORT_CONTROL_INIT,
787 PARPORT_CONTROL_INIT);
788 port->ops->data_reverse (port);
789 for (; len > 0; len--, bp++) {
790 /* Event 67: set nAutoFd (nDStrb) low */
791 parport_frob_control (port,
792 PARPORT_CONTROL_AUTOFD,
793 PARPORT_CONTROL_AUTOFD);
794 /* Event 58: wait for Busy to go high */
795 if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
796 break;
797 }
798
799 *bp = parport_read_data (port);
800
801 /* Event 63: set nAutoFd (nDStrb) high */
802 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
803
804 /* Event 60: wait for Busy to go low */
805 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
806 PARPORT_STATUS_BUSY, 5)) {
807 break;
808 }
809
810 ret++;
811 }
812 port->ops->data_forward (port);
813
814 return ret;
815}
816
817/* EPP mode, forward channel, addresses. */
818size_t parport_ieee1284_epp_write_addr (struct parport *port,
819 const void *buffer, size_t len,
820 int flags)
821{
822 unsigned char *bp = (unsigned char *) buffer;
823 size_t ret = 0;
824
825 /* set EPP idle state (just to make sure) with strobe low */
826 parport_frob_control (port,
827 PARPORT_CONTROL_STROBE |
828 PARPORT_CONTROL_AUTOFD |
829 PARPORT_CONTROL_SELECT |
830 PARPORT_CONTROL_INIT,
831 PARPORT_CONTROL_STROBE |
832 PARPORT_CONTROL_INIT);
833 port->ops->data_forward (port);
834 for (; len > 0; len--, bp++) {
835 /* Event 56: Write data and set nAStrb low. */
836 parport_write_data (port, *bp);
837 parport_frob_control (port, PARPORT_CONTROL_SELECT,
838 PARPORT_CONTROL_SELECT);
839
840 /* Event 58: wait for busy (nWait) to go high */
841 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
842 break;
843
844 /* Event 59: set nAStrb high */
845 parport_frob_control (port, PARPORT_CONTROL_SELECT, 0);
846
847 /* Event 60: wait for busy (nWait) to go low */
848 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
849 PARPORT_STATUS_BUSY, 5))
850 break;
851
852 ret++;
853 }
854
855 /* Event 61: set strobe (nWrite) high */
856 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
857
858 return ret;
859}
860
861/* EPP mode, reverse channel, addresses. */
862size_t parport_ieee1284_epp_read_addr (struct parport *port,
863 void *buffer, size_t len,
864 int flags)
865{
866 unsigned char *bp = (unsigned char *) buffer;
867 unsigned ret = 0;
868
869 /* Set EPP idle state (just to make sure) with strobe high */
870 parport_frob_control (port,
871 PARPORT_CONTROL_STROBE |
872 PARPORT_CONTROL_AUTOFD |
873 PARPORT_CONTROL_SELECT |
874 PARPORT_CONTROL_INIT,
875 PARPORT_CONTROL_INIT);
876 port->ops->data_reverse (port);
877 for (; len > 0; len--, bp++) {
878 /* Event 64: set nSelectIn (nAStrb) low */
879 parport_frob_control (port, PARPORT_CONTROL_SELECT,
880 PARPORT_CONTROL_SELECT);
881
882 /* Event 58: wait for Busy to go high */
883 if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
884 break;
885 }
886
887 *bp = parport_read_data (port);
888
889 /* Event 59: set nSelectIn (nAStrb) high */
890 parport_frob_control (port, PARPORT_CONTROL_SELECT,
13050d89 891 0);
1da177e4
LT		 892
893 /* Event 60: wait for Busy to go low */
894 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
895 PARPORT_STATUS_BUSY, 5))
896 break;
897
898 ret++;
899 }
900 port->ops->data_forward (port);
901
902 return ret;
903}
904
905EXPORT_SYMBOL(parport_ieee1284_ecp_write_data);
906EXPORT_SYMBOL(parport_ieee1284_ecp_read_data);
907EXPORT_SYMBOL(parport_ieee1284_ecp_write_addr);
908EXPORT_SYMBOL(parport_ieee1284_write_compat);
909EXPORT_SYMBOL(parport_ieee1284_read_nibble);
910EXPORT_SYMBOL(parport_ieee1284_read_byte);
911EXPORT_SYMBOL(parport_ieee1284_epp_write_data);
912EXPORT_SYMBOL(parport_ieee1284_epp_read_data);
913EXPORT_SYMBOL(parport_ieee1284_epp_write_addr);
914EXPORT_SYMBOL(parport_ieee1284_epp_read_addr);
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