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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 <tim@cyberelk.demon.co.uk>
12 * Fixed AUTOFD polarity in ecp_forward_to_reverse(). Fred Barnes, 1999
13 * Software emulated EPP fixes, Fred Barnes, 04/2001.
14 */
15
16
17#include <linux/module.h>
18#include <linux/parport.h>
19#include <linux/delay.h>
20#include <linux/sched.h>
21#include <asm/uaccess.h>
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;
62 long wait = msecs_to_jiffies(10);
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);
99 schedule_timeout_interruptible(wait);
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)) {
167 goto end_of_data;
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
217 if (i == len) {
218 /* Read the last nibble without checking data avail. */
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 }
231 else
232 port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
233 }
234
235 return i/2;
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) {
255 goto end_of_data;
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. */
307 if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
308 end_of_data:
309 DPRINTK (KERN_DEBUG
310 "%s: No more byte data (%Zd bytes)\n",
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 }
319 else
320 port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
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);
539 schedule_timeout_interruptible(msecs_to_jiffies(40));
540 parport_claim_or_block (dev);
541 }
542 else
543 /* We must have the device claimed here. */
544 parport_wait_event (port, msecs_to_jiffies(40));
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,
891 0);
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);
1// SPDX-License-Identifier: GPL-2.0
2/* IEEE-1284 operations for parport.
3 *
4 * This file is for generic IEEE 1284 operations. The idea is that
5 * they are used by the low-level drivers. If they have a special way
6 * of doing something, they can provide their own routines (and put
7 * the function pointers in port->ops); if not, they can just use these
8 * as a fallback.
9 *
10 * Note: Make no assumptions about hardware or architecture in this file!
11 *
12 * Author: Tim Waugh <tim@cyberelk.demon.co.uk>
13 * Fixed AUTOFD polarity in ecp_forward_to_reverse(). Fred Barnes, 1999
14 * Software emulated EPP fixes, Fred Barnes, 04/2001.
15 */
16
17
18#include <linux/module.h>
19#include <linux/parport.h>
20#include <linux/delay.h>
21#include <linux/sched/signal.h>
22#include <linux/uaccess.h>
23
24#undef DEBUG /* undef me for production */
25
26#ifdef CONFIG_LP_CONSOLE
27#undef DEBUG /* Don't want a garbled console */
28#endif
29
30/*** *
31 * One-way data transfer functions. *
32 * ***/
33
34/* Compatibility mode. */
35size_t parport_ieee1284_write_compat (struct parport *port,
36 const void *buffer, size_t len,
37 int flags)
38{
39 int no_irq = 1;
40 ssize_t count = 0;
41 const unsigned char *addr = buffer;
42 unsigned char byte;
43 struct pardevice *dev = port->physport->cad;
44 unsigned char ctl = (PARPORT_CONTROL_SELECT
45 | PARPORT_CONTROL_INIT);
46
47 if (port->irq != PARPORT_IRQ_NONE) {
48 parport_enable_irq (port);
49 no_irq = 0;
50 }
51
52 port->physport->ieee1284.phase = IEEE1284_PH_FWD_DATA;
53 parport_write_control (port, ctl);
54 parport_data_forward (port);
55 while (count < len) {
56 unsigned long expire = jiffies + dev->timeout;
57 long wait = msecs_to_jiffies(10);
58 unsigned char mask = (PARPORT_STATUS_ERROR
59 | PARPORT_STATUS_BUSY);
60 unsigned char val = (PARPORT_STATUS_ERROR
61 | PARPORT_STATUS_BUSY);
62
63 /* Wait until the peripheral's ready */
64 do {
65 /* Is the peripheral ready yet? */
66 if (!parport_wait_peripheral (port, mask, val))
67 /* Skip the loop */
68 goto ready;
69
70 /* Is the peripheral upset? */
71 if ((parport_read_status (port) &
72 (PARPORT_STATUS_PAPEROUT |
73 PARPORT_STATUS_SELECT |
74 PARPORT_STATUS_ERROR))
75 != (PARPORT_STATUS_SELECT |
76 PARPORT_STATUS_ERROR))
77 /* If nFault is asserted (i.e. no
78 * error) and PAPEROUT and SELECT are
79 * just red herrings, give the driver
80 * a chance to check it's happy with
81 * that before continuing. */
82 goto stop;
83
84 /* Have we run out of time? */
85 if (!time_before (jiffies, expire))
86 break;
87
88 /* Yield the port for a while. If this is the
89 first time around the loop, don't let go of
90 the port. This way, we find out if we have
91 our interrupt handler called. */
92 if (count && no_irq) {
93 parport_release (dev);
94 schedule_timeout_interruptible(wait);
95 parport_claim_or_block (dev);
96 }
97 else
98 /* We must have the device claimed here */
99 parport_wait_event (port, wait);
100
101 /* Is there a signal pending? */
102 if (signal_pending (current))
103 break;
104
105 /* Wait longer next time. */
106 wait *= 2;
107 } while (time_before (jiffies, expire));
108
109 if (signal_pending (current))
110 break;
111
112 pr_debug("%s: Timed out\n", port->name);
113 break;
114
115 ready:
116 /* Write the character to the data lines. */
117 byte = *addr++;
118 parport_write_data (port, byte);
119 udelay (1);
120
121 /* Pulse strobe. */
122 parport_write_control (port, ctl | PARPORT_CONTROL_STROBE);
123 udelay (1); /* strobe */
124
125 parport_write_control (port, ctl);
126 udelay (1); /* hold */
127
128 /* Assume the peripheral received it. */
129 count++;
130
131 /* Let another process run if it needs to. */
132 if (time_before (jiffies, expire))
133 if (!parport_yield_blocking (dev)
134 && need_resched())
135 schedule ();
136 }
137 stop:
138 port->physport->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
139
140 return count;
141}
142
143/* Nibble mode. */
144size_t parport_ieee1284_read_nibble (struct parport *port,
145 void *buffer, size_t len,
146 int flags)
147{
148#ifndef CONFIG_PARPORT_1284
149 return 0;
150#else
151 unsigned char *buf = buffer;
152 int i;
153 unsigned char byte = 0;
154
155 len *= 2; /* in nibbles */
156 for (i=0; i < len; i++) {
157 unsigned char nibble;
158
159 /* Does the error line indicate end of data? */
160 if (((i & 1) == 0) &&
161 (parport_read_status(port) & PARPORT_STATUS_ERROR)) {
162 goto end_of_data;
163 }
164
165 /* Event 7: Set nAutoFd low. */
166 parport_frob_control (port,
167 PARPORT_CONTROL_AUTOFD,
168 PARPORT_CONTROL_AUTOFD);
169
170 /* Event 9: nAck goes low. */
171 port->ieee1284.phase = IEEE1284_PH_REV_DATA;
172 if (parport_wait_peripheral (port,
173 PARPORT_STATUS_ACK, 0)) {
174 /* Timeout -- no more data? */
175 pr_debug("%s: Nibble timeout at event 9 (%d bytes)\n",
176 port->name, i / 2);
177 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
178 break;
179 }
180
181
182 /* Read a nibble. */
183 nibble = parport_read_status (port) >> 3;
184 nibble &= ~8;
185 if ((nibble & 0x10) == 0)
186 nibble |= 8;
187 nibble &= 0xf;
188
189 /* Event 10: Set nAutoFd high. */
190 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
191
192 /* Event 11: nAck goes high. */
193 if (parport_wait_peripheral (port,
194 PARPORT_STATUS_ACK,
195 PARPORT_STATUS_ACK)) {
196 /* Timeout -- no more data? */
197 pr_debug("%s: Nibble timeout at event 11\n",
198 port->name);
199 break;
200 }
201
202 if (i & 1) {
203 /* Second nibble */
204 byte |= nibble << 4;
205 *buf++ = byte;
206 } else
207 byte = nibble;
208 }
209
210 if (i == len) {
211 /* Read the last nibble without checking data avail. */
212 if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
213 end_of_data:
214 pr_debug("%s: No more nibble data (%d bytes)\n",
215 port->name, i / 2);
216
217 /* Go to reverse idle phase. */
218 parport_frob_control (port,
219 PARPORT_CONTROL_AUTOFD,
220 PARPORT_CONTROL_AUTOFD);
221 port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
222 }
223 else
224 port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
225 }
226
227 return i/2;
228#endif /* IEEE1284 support */
229}
230
231/* Byte mode. */
232size_t parport_ieee1284_read_byte (struct parport *port,
233 void *buffer, size_t len,
234 int flags)
235{
236#ifndef CONFIG_PARPORT_1284
237 return 0;
238#else
239 unsigned char *buf = buffer;
240 ssize_t count = 0;
241
242 for (count = 0; count < len; count++) {
243 unsigned char byte;
244
245 /* Data available? */
246 if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
247 goto end_of_data;
248 }
249
250 /* Event 14: Place data bus in high impedance state. */
251 parport_data_reverse (port);
252
253 /* Event 7: Set nAutoFd low. */
254 parport_frob_control (port,
255 PARPORT_CONTROL_AUTOFD,
256 PARPORT_CONTROL_AUTOFD);
257
258 /* Event 9: nAck goes low. */
259 port->physport->ieee1284.phase = IEEE1284_PH_REV_DATA;
260 if (parport_wait_peripheral (port,
261 PARPORT_STATUS_ACK,
262 0)) {
263 /* Timeout -- no more data? */
264 parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
265 0);
266 pr_debug("%s: Byte timeout at event 9\n", port->name);
267 break;
268 }
269
270 byte = parport_read_data (port);
271 *buf++ = byte;
272
273 /* Event 10: Set nAutoFd high */
274 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
275
276 /* Event 11: nAck goes high. */
277 if (parport_wait_peripheral (port,
278 PARPORT_STATUS_ACK,
279 PARPORT_STATUS_ACK)) {
280 /* Timeout -- no more data? */
281 pr_debug("%s: Byte timeout at event 11\n", port->name);
282 break;
283 }
284
285 /* Event 16: Set nStrobe low. */
286 parport_frob_control (port,
287 PARPORT_CONTROL_STROBE,
288 PARPORT_CONTROL_STROBE);
289 udelay (5);
290
291 /* Event 17: Set nStrobe high. */
292 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
293 }
294
295 if (count == len) {
296 /* Read the last byte without checking data avail. */
297 if (parport_read_status (port) & PARPORT_STATUS_ERROR) {
298 end_of_data:
299 pr_debug("%s: No more byte data (%zd bytes)\n",
300 port->name, count);
301
302 /* Go to reverse idle phase. */
303 parport_frob_control (port,
304 PARPORT_CONTROL_AUTOFD,
305 PARPORT_CONTROL_AUTOFD);
306 port->physport->ieee1284.phase = IEEE1284_PH_REV_IDLE;
307 }
308 else
309 port->physport->ieee1284.phase = IEEE1284_PH_HBUSY_DAVAIL;
310 }
311
312 return count;
313#endif /* IEEE1284 support */
314}
315
316/*** *
317 * ECP Functions. *
318 * ***/
319
320#ifdef CONFIG_PARPORT_1284
321
322static inline
323int ecp_forward_to_reverse (struct parport *port)
324{
325 int retval;
326
327 /* Event 38: Set nAutoFd low */
328 parport_frob_control (port,
329 PARPORT_CONTROL_AUTOFD,
330 PARPORT_CONTROL_AUTOFD);
331 parport_data_reverse (port);
332 udelay (5);
333
334 /* Event 39: Set nInit low to initiate bus reversal */
335 parport_frob_control (port,
336 PARPORT_CONTROL_INIT,
337 0);
338
339 /* Event 40: PError goes low */
340 retval = parport_wait_peripheral (port,
341 PARPORT_STATUS_PAPEROUT, 0);
342
343 if (!retval) {
344 pr_debug("%s: ECP direction: reverse\n", port->name);
345 port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
346 } else {
347 pr_debug("%s: ECP direction: failed to reverse\n", port->name);
348 port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
349 }
350
351 return retval;
352}
353
354static inline
355int ecp_reverse_to_forward (struct parport *port)
356{
357 int retval;
358
359 /* Event 47: Set nInit high */
360 parport_frob_control (port,
361 PARPORT_CONTROL_INIT
362 | PARPORT_CONTROL_AUTOFD,
363 PARPORT_CONTROL_INIT
364 | PARPORT_CONTROL_AUTOFD);
365
366 /* Event 49: PError goes high */
367 retval = parport_wait_peripheral (port,
368 PARPORT_STATUS_PAPEROUT,
369 PARPORT_STATUS_PAPEROUT);
370
371 if (!retval) {
372 parport_data_forward (port);
373 pr_debug("%s: ECP direction: forward\n", port->name);
374 port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
375 } else {
376 pr_debug("%s: ECP direction: failed to switch forward\n",
377 port->name);
378 port->ieee1284.phase = IEEE1284_PH_ECP_DIR_UNKNOWN;
379 }
380
381
382 return retval;
383}
384
385#endif /* IEEE1284 support */
386
387/* ECP mode, forward channel, data. */
388size_t parport_ieee1284_ecp_write_data (struct parport *port,
389 const void *buffer, size_t len,
390 int flags)
391{
392#ifndef CONFIG_PARPORT_1284
393 return 0;
394#else
395 const unsigned char *buf = buffer;
396 size_t written;
397 int retry;
398
399 port = port->physport;
400
401 if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
402 if (ecp_reverse_to_forward (port))
403 return 0;
404
405 port->ieee1284.phase = IEEE1284_PH_FWD_DATA;
406
407 /* HostAck high (data, not command) */
408 parport_frob_control (port,
409 PARPORT_CONTROL_AUTOFD
410 | PARPORT_CONTROL_STROBE
411 | PARPORT_CONTROL_INIT,
412 PARPORT_CONTROL_INIT);
413 for (written = 0; written < len; written++, buf++) {
414 unsigned long expire = jiffies + port->cad->timeout;
415 unsigned char byte;
416
417 byte = *buf;
418 try_again:
419 parport_write_data (port, byte);
420 parport_frob_control (port, PARPORT_CONTROL_STROBE,
421 PARPORT_CONTROL_STROBE);
422 udelay (5);
423 for (retry = 0; retry < 100; retry++) {
424 if (!parport_wait_peripheral (port,
425 PARPORT_STATUS_BUSY, 0))
426 goto success;
427
428 if (signal_pending (current)) {
429 parport_frob_control (port,
430 PARPORT_CONTROL_STROBE,
431 0);
432 break;
433 }
434 }
435
436 /* Time for Host Transfer Recovery (page 41 of IEEE1284) */
437 pr_debug("%s: ECP transfer stalled!\n", port->name);
438
439 parport_frob_control (port, PARPORT_CONTROL_INIT,
440 PARPORT_CONTROL_INIT);
441 udelay (50);
442 if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
443 /* It's buggered. */
444 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
445 break;
446 }
447
448 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
449 udelay (50);
450 if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
451 break;
452
453 pr_debug("%s: Host transfer recovered\n", port->name);
454
455 if (time_after_eq (jiffies, expire)) break;
456 goto try_again;
457 success:
458 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
459 udelay (5);
460 if (parport_wait_peripheral (port,
461 PARPORT_STATUS_BUSY,
462 PARPORT_STATUS_BUSY))
463 /* Peripheral hasn't accepted the data. */
464 break;
465 }
466
467 port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
468
469 return written;
470#endif /* IEEE1284 support */
471}
472
473/* ECP mode, reverse channel, data. */
474size_t parport_ieee1284_ecp_read_data (struct parport *port,
475 void *buffer, size_t len, int flags)
476{
477#ifndef CONFIG_PARPORT_1284
478 return 0;
479#else
480 struct pardevice *dev = port->cad;
481 unsigned char *buf = buffer;
482 int rle_count = 0; /* shut gcc up */
483 unsigned char ctl;
484 int rle = 0;
485 ssize_t count = 0;
486
487 port = port->physport;
488
489 if (port->ieee1284.phase != IEEE1284_PH_REV_IDLE)
490 if (ecp_forward_to_reverse (port))
491 return 0;
492
493 port->ieee1284.phase = IEEE1284_PH_REV_DATA;
494
495 /* Set HostAck low to start accepting data. */
496 ctl = parport_read_control (port);
497 ctl &= ~(PARPORT_CONTROL_STROBE | PARPORT_CONTROL_INIT |
498 PARPORT_CONTROL_AUTOFD);
499 parport_write_control (port,
500 ctl | PARPORT_CONTROL_AUTOFD);
501 while (count < len) {
502 unsigned long expire = jiffies + dev->timeout;
503 unsigned char byte;
504 int command;
505
506 /* Event 43: Peripheral sets nAck low. It can take as
507 long as it wants. */
508 while (parport_wait_peripheral (port, PARPORT_STATUS_ACK, 0)) {
509 /* The peripheral hasn't given us data in
510 35ms. If we have data to give back to the
511 caller, do it now. */
512 if (count)
513 goto out;
514
515 /* If we've used up all the time we were allowed,
516 give up altogether. */
517 if (!time_before (jiffies, expire))
518 goto out;
519
520 /* Yield the port for a while. */
521 if (dev->port->irq != PARPORT_IRQ_NONE) {
522 parport_release (dev);
523 schedule_timeout_interruptible(msecs_to_jiffies(40));
524 parport_claim_or_block (dev);
525 }
526 else
527 /* We must have the device claimed here. */
528 parport_wait_event (port, msecs_to_jiffies(40));
529
530 /* Is there a signal pending? */
531 if (signal_pending (current))
532 goto out;
533 }
534
535 /* Is this a command? */
536 if (rle)
537 /* The last byte was a run-length count, so
538 this can't be as well. */
539 command = 0;
540 else
541 command = (parport_read_status (port) &
542 PARPORT_STATUS_BUSY) ? 1 : 0;
543
544 /* Read the data. */
545 byte = parport_read_data (port);
546
547 /* If this is a channel command, rather than an RLE
548 command or a normal data byte, don't accept it. */
549 if (command) {
550 if (byte & 0x80) {
551 pr_debug("%s: stopping short at channel command (%02x)\n",
552 port->name, byte);
553 goto out;
554 }
555 else if (port->ieee1284.mode != IEEE1284_MODE_ECPRLE)
556 pr_debug("%s: device illegally using RLE; accepting anyway\n",
557 port->name);
558
559 rle_count = byte + 1;
560
561 /* Are we allowed to read that many bytes? */
562 if (rle_count > (len - count)) {
563 pr_debug("%s: leaving %d RLE bytes for next time\n",
564 port->name, rle_count);
565 break;
566 }
567
568 rle = 1;
569 }
570
571 /* Event 44: Set HostAck high, acknowledging handshake. */
572 parport_write_control (port, ctl);
573
574 /* Event 45: The peripheral has 35ms to set nAck high. */
575 if (parport_wait_peripheral (port, PARPORT_STATUS_ACK,
576 PARPORT_STATUS_ACK)) {
577 /* It's gone wrong. Return what data we have
578 to the caller. */
579 pr_debug("ECP read timed out at 45\n");
580
581 if (command)
582 pr_warn("%s: command ignored (%02x)\n",
583 port->name, byte);
584
585 break;
586 }
587
588 /* Event 46: Set HostAck low and accept the data. */
589 parport_write_control (port,
590 ctl | PARPORT_CONTROL_AUTOFD);
591
592 /* If we just read a run-length count, fetch the data. */
593 if (command)
594 continue;
595
596 /* If this is the byte after a run-length count, decompress. */
597 if (rle) {
598 rle = 0;
599 memset (buf, byte, rle_count);
600 buf += rle_count;
601 count += rle_count;
602 pr_debug("%s: decompressed to %d bytes\n",
603 port->name, rle_count);
604 } else {
605 /* Normal data byte. */
606 *buf = byte;
607 buf++, count++;
608 }
609 }
610
611 out:
612 port->ieee1284.phase = IEEE1284_PH_REV_IDLE;
613 return count;
614#endif /* IEEE1284 support */
615}
616
617/* ECP mode, forward channel, commands. */
618size_t parport_ieee1284_ecp_write_addr (struct parport *port,
619 const void *buffer, size_t len,
620 int flags)
621{
622#ifndef CONFIG_PARPORT_1284
623 return 0;
624#else
625 const unsigned char *buf = buffer;
626 size_t written;
627 int retry;
628
629 port = port->physport;
630
631 if (port->ieee1284.phase != IEEE1284_PH_FWD_IDLE)
632 if (ecp_reverse_to_forward (port))
633 return 0;
634
635 port->ieee1284.phase = IEEE1284_PH_FWD_DATA;
636
637 /* HostAck low (command, not data) */
638 parport_frob_control (port,
639 PARPORT_CONTROL_AUTOFD
640 | PARPORT_CONTROL_STROBE
641 | PARPORT_CONTROL_INIT,
642 PARPORT_CONTROL_AUTOFD
643 | PARPORT_CONTROL_INIT);
644 for (written = 0; written < len; written++, buf++) {
645 unsigned long expire = jiffies + port->cad->timeout;
646 unsigned char byte;
647
648 byte = *buf;
649 try_again:
650 parport_write_data (port, byte);
651 parport_frob_control (port, PARPORT_CONTROL_STROBE,
652 PARPORT_CONTROL_STROBE);
653 udelay (5);
654 for (retry = 0; retry < 100; retry++) {
655 if (!parport_wait_peripheral (port,
656 PARPORT_STATUS_BUSY, 0))
657 goto success;
658
659 if (signal_pending (current)) {
660 parport_frob_control (port,
661 PARPORT_CONTROL_STROBE,
662 0);
663 break;
664 }
665 }
666
667 /* Time for Host Transfer Recovery (page 41 of IEEE1284) */
668 pr_debug("%s: ECP transfer stalled!\n", port->name);
669
670 parport_frob_control (port, PARPORT_CONTROL_INIT,
671 PARPORT_CONTROL_INIT);
672 udelay (50);
673 if (parport_read_status (port) & PARPORT_STATUS_PAPEROUT) {
674 /* It's buggered. */
675 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
676 break;
677 }
678
679 parport_frob_control (port, PARPORT_CONTROL_INIT, 0);
680 udelay (50);
681 if (!(parport_read_status (port) & PARPORT_STATUS_PAPEROUT))
682 break;
683
684 pr_debug("%s: Host transfer recovered\n", port->name);
685
686 if (time_after_eq (jiffies, expire)) break;
687 goto try_again;
688 success:
689 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
690 udelay (5);
691 if (parport_wait_peripheral (port,
692 PARPORT_STATUS_BUSY,
693 PARPORT_STATUS_BUSY))
694 /* Peripheral hasn't accepted the data. */
695 break;
696 }
697
698 port->ieee1284.phase = IEEE1284_PH_FWD_IDLE;
699
700 return written;
701#endif /* IEEE1284 support */
702}
703
704/*** *
705 * EPP functions. *
706 * ***/
707
708/* EPP mode, forward channel, data. */
709size_t parport_ieee1284_epp_write_data (struct parport *port,
710 const void *buffer, size_t len,
711 int flags)
712{
713 unsigned char *bp = (unsigned char *) buffer;
714 size_t ret = 0;
715
716 /* set EPP idle state (just to make sure) with strobe low */
717 parport_frob_control (port,
718 PARPORT_CONTROL_STROBE |
719 PARPORT_CONTROL_AUTOFD |
720 PARPORT_CONTROL_SELECT |
721 PARPORT_CONTROL_INIT,
722 PARPORT_CONTROL_STROBE |
723 PARPORT_CONTROL_INIT);
724 port->ops->data_forward (port);
725 for (; len > 0; len--, bp++) {
726 /* Event 62: Write data and set autofd low */
727 parport_write_data (port, *bp);
728 parport_frob_control (port, PARPORT_CONTROL_AUTOFD,
729 PARPORT_CONTROL_AUTOFD);
730
731 /* Event 58: wait for busy (nWait) to go high */
732 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
733 break;
734
735 /* Event 63: set nAutoFd (nDStrb) high */
736 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
737
738 /* Event 60: wait for busy (nWait) to go low */
739 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
740 PARPORT_STATUS_BUSY, 5))
741 break;
742
743 ret++;
744 }
745
746 /* Event 61: set strobe (nWrite) high */
747 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
748
749 return ret;
750}
751
752/* EPP mode, reverse channel, data. */
753size_t parport_ieee1284_epp_read_data (struct parport *port,
754 void *buffer, size_t len,
755 int flags)
756{
757 unsigned char *bp = (unsigned char *) buffer;
758 unsigned ret = 0;
759
760 /* set EPP idle state (just to make sure) with strobe high */
761 parport_frob_control (port,
762 PARPORT_CONTROL_STROBE |
763 PARPORT_CONTROL_AUTOFD |
764 PARPORT_CONTROL_SELECT |
765 PARPORT_CONTROL_INIT,
766 PARPORT_CONTROL_INIT);
767 port->ops->data_reverse (port);
768 for (; len > 0; len--, bp++) {
769 /* Event 67: set nAutoFd (nDStrb) low */
770 parport_frob_control (port,
771 PARPORT_CONTROL_AUTOFD,
772 PARPORT_CONTROL_AUTOFD);
773 /* Event 58: wait for Busy to go high */
774 if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
775 break;
776 }
777
778 *bp = parport_read_data (port);
779
780 /* Event 63: set nAutoFd (nDStrb) high */
781 parport_frob_control (port, PARPORT_CONTROL_AUTOFD, 0);
782
783 /* Event 60: wait for Busy to go low */
784 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
785 PARPORT_STATUS_BUSY, 5)) {
786 break;
787 }
788
789 ret++;
790 }
791 port->ops->data_forward (port);
792
793 return ret;
794}
795
796/* EPP mode, forward channel, addresses. */
797size_t parport_ieee1284_epp_write_addr (struct parport *port,
798 const void *buffer, size_t len,
799 int flags)
800{
801 unsigned char *bp = (unsigned char *) buffer;
802 size_t ret = 0;
803
804 /* set EPP idle state (just to make sure) with strobe low */
805 parport_frob_control (port,
806 PARPORT_CONTROL_STROBE |
807 PARPORT_CONTROL_AUTOFD |
808 PARPORT_CONTROL_SELECT |
809 PARPORT_CONTROL_INIT,
810 PARPORT_CONTROL_STROBE |
811 PARPORT_CONTROL_INIT);
812 port->ops->data_forward (port);
813 for (; len > 0; len--, bp++) {
814 /* Event 56: Write data and set nAStrb low. */
815 parport_write_data (port, *bp);
816 parport_frob_control (port, PARPORT_CONTROL_SELECT,
817 PARPORT_CONTROL_SELECT);
818
819 /* Event 58: wait for busy (nWait) to go high */
820 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY, 0, 10))
821 break;
822
823 /* Event 59: set nAStrb high */
824 parport_frob_control (port, PARPORT_CONTROL_SELECT, 0);
825
826 /* Event 60: wait for busy (nWait) to go low */
827 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
828 PARPORT_STATUS_BUSY, 5))
829 break;
830
831 ret++;
832 }
833
834 /* Event 61: set strobe (nWrite) high */
835 parport_frob_control (port, PARPORT_CONTROL_STROBE, 0);
836
837 return ret;
838}
839
840/* EPP mode, reverse channel, addresses. */
841size_t parport_ieee1284_epp_read_addr (struct parport *port,
842 void *buffer, size_t len,
843 int flags)
844{
845 unsigned char *bp = (unsigned char *) buffer;
846 unsigned ret = 0;
847
848 /* Set EPP idle state (just to make sure) with strobe high */
849 parport_frob_control (port,
850 PARPORT_CONTROL_STROBE |
851 PARPORT_CONTROL_AUTOFD |
852 PARPORT_CONTROL_SELECT |
853 PARPORT_CONTROL_INIT,
854 PARPORT_CONTROL_INIT);
855 port->ops->data_reverse (port);
856 for (; len > 0; len--, bp++) {
857 /* Event 64: set nSelectIn (nAStrb) low */
858 parport_frob_control (port, PARPORT_CONTROL_SELECT,
859 PARPORT_CONTROL_SELECT);
860
861 /* Event 58: wait for Busy to go high */
862 if (parport_wait_peripheral (port, PARPORT_STATUS_BUSY, 0)) {
863 break;
864 }
865
866 *bp = parport_read_data (port);
867
868 /* Event 59: set nSelectIn (nAStrb) high */
869 parport_frob_control (port, PARPORT_CONTROL_SELECT,
870 0);
871
872 /* Event 60: wait for Busy to go low */
873 if (parport_poll_peripheral (port, PARPORT_STATUS_BUSY,
874 PARPORT_STATUS_BUSY, 5))
875 break;
876
877 ret++;
878 }
879 port->ops->data_forward (port);
880
881 return ret;
882}
883
884EXPORT_SYMBOL(parport_ieee1284_ecp_write_data);
885EXPORT_SYMBOL(parport_ieee1284_ecp_read_data);
886EXPORT_SYMBOL(parport_ieee1284_ecp_write_addr);
887EXPORT_SYMBOL(parport_ieee1284_write_compat);
888EXPORT_SYMBOL(parport_ieee1284_read_nibble);
889EXPORT_SYMBOL(parport_ieee1284_read_byte);
890EXPORT_SYMBOL(parport_ieee1284_epp_write_data);
891EXPORT_SYMBOL(parport_ieee1284_epp_read_data);
892EXPORT_SYMBOL(parport_ieee1284_epp_write_addr);
893EXPORT_SYMBOL(parport_ieee1284_epp_read_addr);