summaryrefslogtreecommitdiff
path: root/drivers/char/ftape/lowlevel/ftape-io.c
blob: 259015aeff5592150dfdd16e7e96da7e2d8e6e8e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
/*
 *      Copyright (C) 1993-1996 Bas Laarhoven,
 *                (C) 1996      Kai Harrekilde-Petersen,
 *                (C) 1997      Claus-Justus Heine.

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2, or (at your option)
 any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; see the file COPYING.  If not, write to
 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

 *
 * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-io.c,v $
 * $Revision: 1.4 $
 * $Date: 1997/11/11 14:02:36 $
 *
 *      This file contains the general control functions for the
 *      QIC-40/80/3010/3020 floppy-tape driver "ftape" for Linux.
 */

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <asm/system.h>
#include <linux/ioctl.h>
#include <linux/mtio.h>
#include <linux/delay.h>

#include <linux/ftape.h>
#include <linux/qic117.h>
#include "../lowlevel/ftape-tracing.h"
#include "../lowlevel/fdc-io.h"
#include "../lowlevel/ftape-io.h"
#include "../lowlevel/ftape-ctl.h"
#include "../lowlevel/ftape-rw.h"
#include "../lowlevel/ftape-write.h"
#include "../lowlevel/ftape-read.h"
#include "../lowlevel/ftape-init.h"
#include "../lowlevel/ftape-calibr.h"

/*      Global vars.
 */
/* NOTE: sectors start numbering at 1, all others at 0 ! */
ft_timeout_table ftape_timeout;
unsigned int ftape_tape_len;
volatile qic117_cmd_t ftape_current_command;
const struct qic117_command_table qic117_cmds[] = QIC117_COMMANDS;
int ftape_might_be_off_track;

/*      Local vars.
 */
static int diagnostic_mode;
static unsigned int ftape_udelay_count;
static unsigned int ftape_udelay_time;

void ftape_udelay(unsigned int usecs)
{
	volatile int count = (ftape_udelay_count * usecs +
                              ftape_udelay_count - 1) / ftape_udelay_time;
	volatile int i;

	while (count-- > 0) {
		for (i = 0; i < 20; ++i);
	}
}

void ftape_udelay_calibrate(void)
{
	ftape_calibrate("ftape_udelay",
			ftape_udelay, &ftape_udelay_count, &ftape_udelay_time);
}

/*      Delay (msec) routine.
 */
void ftape_sleep(unsigned int time)
{
	TRACE_FUN(ft_t_any);

	time *= 1000;   /* msecs -> usecs */
	if (time < FT_USPT) {
		/*  Time too small for scheduler, do a busy wait ! */
		ftape_udelay(time);
	} else {
		long timeout;
		unsigned long flags;
		unsigned int ticks = (time + FT_USPT - 1) / FT_USPT;

		TRACE(ft_t_any, "%d msec, %d ticks", time/1000, ticks);
		timeout = ticks;
		save_flags(flags);
		sti();
		msleep_interruptible(jiffies_to_msecs(timeout));
		/*  Mmm. Isn't current->blocked == 0xffffffff ?
		 */
		if (signal_pending(current)) {
			TRACE(ft_t_err, "awoken by non-blocked signal :-(");
		}
		restore_flags(flags);
	}
	TRACE_EXIT;
}

/*  send a command or parameter to the drive
 *  Generates # of step pulses.
 */
static inline int ft_send_to_drive(int arg)
{
	/*  Always wait for a command_timeout period to separate
	 *  individuals commands and/or parameters.
	 */
	ftape_sleep(3 * FT_MILLISECOND);
	/*  Keep cylinder nr within range, step towards home if possible.
	 */
	if (ftape_current_cylinder >= arg) {
		return fdc_seek(ftape_current_cylinder - arg);
	} else {
		return fdc_seek(ftape_current_cylinder + arg);
	}
}

/* forward */ int ftape_report_raw_drive_status(int *status);

static int ft_check_cmd_restrictions(qic117_cmd_t command)
{
	int status = -1;
	TRACE_FUN(ft_t_any);
	
	TRACE(ft_t_flow, "%s", qic117_cmds[command].name);
	/* A new motion command during an uninterruptible (motion)
	 *  command requires a ready status before the new command can
	 *  be issued. Otherwise a new motion command needs to be
	 *  checked against required status.
	 */
	if (qic117_cmds[command].cmd_type == motion &&
	    qic117_cmds[ftape_current_command].non_intr) {
		ftape_report_raw_drive_status(&status);
		if ((status & QIC_STATUS_READY) == 0) {
			TRACE(ft_t_noise,
			      "motion cmd (%d) during non-intr cmd (%d)",
			      command, ftape_current_command);
			TRACE(ft_t_noise, "waiting until drive gets ready");
			ftape_ready_wait(ftape_timeout.seek,
					 &status);
		}
	}
	if (qic117_cmds[command].mask != 0) {
		__u8 difference;
		/*  Some commands do require a certain status:
		 */
		if (status == -1) {	/* not yet set */
			ftape_report_raw_drive_status(&status);
		}
		difference = ((status ^ qic117_cmds[command].state) &
			      qic117_cmds[command].mask);
		/*  Wait until the drive gets
		 *  ready. This may last forever if
		 *  the drive never gets ready... 
		 */
		while ((difference & QIC_STATUS_READY) != 0) {
			TRACE(ft_t_noise, "command %d issued while not ready",
			      command);
			TRACE(ft_t_noise, "waiting until drive gets ready");
			if (ftape_ready_wait(ftape_timeout.seek,
					     &status) == -EINTR) {
				/*  Bail out on signal !
				 */
				TRACE_ABORT(-EINTR, ft_t_warn,
				      "interrupted by non-blockable signal");
			}
			difference = ((status ^ qic117_cmds[command].state) &
				      qic117_cmds[command].mask);
		}
		while ((difference & QIC_STATUS_ERROR) != 0) {
			int err;
			qic117_cmd_t cmd;

			TRACE(ft_t_noise,
			      "command %d issued while error pending",
			      command);
			TRACE(ft_t_noise, "clearing error status");
			ftape_report_error(&err, &cmd, 1);
			ftape_report_raw_drive_status(&status);
			difference = ((status ^ qic117_cmds[command].state) &
				      qic117_cmds[command].mask);
			if ((difference & QIC_STATUS_ERROR) != 0) {
				/*  Bail out on fatal signal !
				 */
				FT_SIGNAL_EXIT(_NEVER_BLOCK);
			}
		}
		if (difference) {
			/*  Any remaining difference can't be solved
			 *  here.  
			 */
			if (difference & (QIC_STATUS_CARTRIDGE_PRESENT |
					  QIC_STATUS_NEW_CARTRIDGE |
					  QIC_STATUS_REFERENCED)) {
				TRACE(ft_t_warn,
				      "Fatal: tape removed or reinserted !");
				ft_failure = 1;
			} else {
				TRACE(ft_t_err, "wrong state: 0x%02x should be: 0x%02x",
				      status & qic117_cmds[command].mask,
				      qic117_cmds[command].state);
			}
			TRACE_EXIT -EIO;
		}
		if (~status & QIC_STATUS_READY & qic117_cmds[command].mask) {
			TRACE_ABORT(-EBUSY, ft_t_err, "Bad: still busy!");
		}
	}
	TRACE_EXIT 0;
}

/*      Issue a tape command:
 */
int ftape_command(qic117_cmd_t command)
{
	int result = 0;
	static int level;
	TRACE_FUN(ft_t_any);

	if ((unsigned int)command > NR_ITEMS(qic117_cmds)) {
		/*  This is a bug we'll want to know about too.
		 */
		TRACE_ABORT(-EIO, ft_t_bug, "bug - bad command: %d", command);
	}
	if (++level > 5) { /*  This is a bug we'll want to know about. */
		--level;
		TRACE_ABORT(-EIO, ft_t_bug, "bug - recursion for command: %d",
			    command);
	}
	/*  disable logging and restriction check for some commands,
	 *  check all other commands that have a prescribed starting
	 *  status.
	 */
	if (diagnostic_mode) {
		TRACE(ft_t_flow, "diagnostic command %d", command);
	} else if (command == QIC_REPORT_DRIVE_STATUS ||
		   command == QIC_REPORT_NEXT_BIT) {
		TRACE(ft_t_any, "%s", qic117_cmds[command].name);
	} else {
		TRACE_CATCH(ft_check_cmd_restrictions(command), --level);
	}
	/*  Now all conditions are met or result was < 0.
	 */
	result = ft_send_to_drive((unsigned int)command);
	if (qic117_cmds[command].cmd_type == motion &&
	    command != QIC_LOGICAL_FORWARD && command != QIC_STOP_TAPE) {
		ft_location.known = 0;
	}
	ftape_current_command = command;
	--level;
	TRACE_EXIT result;
}

/*      Send a tape command parameter:
 *      Generates command # of step pulses.
 *      Skips tape-status call !
 */
int ftape_parameter(unsigned int parameter)
{
	TRACE_FUN(ft_t_any);

	TRACE(ft_t_flow, "called with parameter = %d", parameter);
	TRACE_EXIT ft_send_to_drive(parameter + 2);
}

/*      Wait for the drive to get ready.
 *      timeout time in milli-seconds
 *      Returned status is valid if result != -EIO
 *
 *      Should we allow to be killed by SIGINT?  (^C)
 *      Would be nice at least for large timeouts.
 */
int ftape_ready_wait(unsigned int timeout, int *status)
{
	unsigned long t0;
	unsigned int poll_delay;
	int signal_retries;
	TRACE_FUN(ft_t_any);

	/*  the following ** REALLY ** reduces the system load when
	 *  e.g. one simply rewinds or retensions. The tape is slow 
	 *  anyway. It is really not necessary to detect error 
	 *  conditions with 1/10 seconds granularity
	 *
	 *  On my AMD 133MHZ 486: 100 ms: 23% system load
	 *                        1  sec:  5%
	 *                        5  sec:  0.6%, yeah
	 */
	if (timeout <= FT_SECOND) {
		poll_delay = 100 * FT_MILLISECOND;
		signal_retries = 20; /* two seconds */
	} else if (timeout < 20 * FT_SECOND) {
		TRACE(ft_t_flow, "setting poll delay to 1 second");
		poll_delay = FT_SECOND;
		signal_retries = 2; /* two seconds */
	} else {
		TRACE(ft_t_flow, "setting poll delay to 5 seconds");
		poll_delay = 5 * FT_SECOND;
		signal_retries = 1; /* five seconds */
	}
	for (;;) {
		t0 = jiffies;
		TRACE_CATCH(ftape_report_raw_drive_status(status),);
		if (*status & QIC_STATUS_READY) {
			TRACE_EXIT 0;
		}
		if (!signal_retries--) {
			FT_SIGNAL_EXIT(_NEVER_BLOCK);
		}
		if ((int)timeout >= 0) {
			/* this will fail when jiffies wraps around about
			 * once every year :-)
			 */
			timeout -= ((jiffies - t0) * FT_SECOND) / HZ;
			if (timeout <= 0) {
				TRACE_ABORT(-ETIME, ft_t_err, "timeout");
			}
			ftape_sleep(poll_delay);
			timeout -= poll_delay;
		} else {
			ftape_sleep(poll_delay);
		}
	}
	TRACE_EXIT -ETIME;
}

/*      Issue command and wait up to timeout milli seconds for drive ready
 */
int ftape_command_wait(qic117_cmd_t command, unsigned int timeout, int *status)
{
	int result;

	/* Drive should be ready, issue command
	 */
	result = ftape_command(command);
	if (result >= 0) {
		result = ftape_ready_wait(timeout, status);
	}
	return result;
}

static int ftape_parameter_wait(unsigned int parm, unsigned int timeout, int *status)
{
	int result;

	/* Drive should be ready, issue command
	 */
	result = ftape_parameter(parm);
	if (result >= 0) {
		result = ftape_ready_wait(timeout, status);
	}
	return result;
}

/*--------------------------------------------------------------------------
 *      Report operations
 */

/* Query the drive about its status.  The command is sent and
   result_length bits of status are returned (2 extra bits are read
   for start and stop). */

int ftape_report_operation(int *status,
			   qic117_cmd_t command,
			   int result_length)
{
	int i, st3;
	unsigned int t0;
	unsigned int dt;
	TRACE_FUN(ft_t_any);

	TRACE_CATCH(ftape_command(command),);
	t0 = ftape_timestamp();
	i = 0;
	do {
		++i;
		ftape_sleep(3 * FT_MILLISECOND);	/* see remark below */
		TRACE_CATCH(fdc_sense_drive_status(&st3),);
		dt = ftape_timediff(t0, ftape_timestamp());
		/*  Ack should be asserted within Ttimout + Tack = 6 msec.
		 *  Looks like some drives fail to do this so extend this
		 *  period to 300 msec.
		 */
	} while (!(st3 & ST3_TRACK_0) && dt < 300000);
	if (!(st3 & ST3_TRACK_0)) {
		TRACE(ft_t_err,
		      "No acknowledge after %u msec. (%i iter)", dt / 1000, i);
		TRACE_ABORT(-EIO, ft_t_err, "timeout on Acknowledge");
	}
	/*  dt may be larger than expected because of other tasks
	 *  scheduled while we were sleeping.
	 */
	if (i > 1 && dt > 6000) {
		TRACE(ft_t_err, "Acknowledge after %u msec. (%i iter)",
		      dt / 1000, i);
	}
	*status = 0;
	for (i = 0; i < result_length + 1; i++) {
		TRACE_CATCH(ftape_command(QIC_REPORT_NEXT_BIT),);
		TRACE_CATCH(fdc_sense_drive_status(&st3),);
		if (i < result_length) {
			*status |= ((st3 & ST3_TRACK_0) ? 1 : 0) << i;
		} else if ((st3 & ST3_TRACK_0) == 0) {
			TRACE_ABORT(-EIO, ft_t_err, "missing status stop bit");
		}
	}
	/* this command will put track zero and index back into normal state */
	(void)ftape_command(QIC_REPORT_NEXT_BIT);
	TRACE_EXIT 0;
}

/* Report the current drive status. */

int ftape_report_raw_drive_status(int *status)
{
	int result;
	int count = 0;
	TRACE_FUN(ft_t_any);

	do {
		result = ftape_report_operation(status,
						QIC_REPORT_DRIVE_STATUS, 8);
	} while (result < 0 && ++count <= 3);
	if (result < 0) {
		TRACE_ABORT(-EIO, ft_t_err,
			    "report_operation failed after %d trials", count);
	}
	if ((*status & 0xff) == 0xff) {
		TRACE_ABORT(-EIO, ft_t_err,
			    "impossible drive status 0xff");
	}
	if (*status & QIC_STATUS_READY) {
		ftape_current_command = QIC_NO_COMMAND; /* completed */
	}
	ft_last_status.status.drive_status = (__u8)(*status & 0xff);
	TRACE_EXIT 0;
}

int ftape_report_drive_status(int *status)
{
	TRACE_FUN(ft_t_any);

	TRACE_CATCH(ftape_report_raw_drive_status(status),);
	if (*status & QIC_STATUS_NEW_CARTRIDGE ||
	    !(*status & QIC_STATUS_CARTRIDGE_PRESENT)) {
		ft_failure = 1;	/* will inhibit further operations */
		TRACE_EXIT -EIO;
	}
	if (*status & QIC_STATUS_READY && *status & QIC_STATUS_ERROR) {
		/*  Let caller handle all errors */
		TRACE_ABORT(1, ft_t_warn, "warning: error status set!");
	}
	TRACE_EXIT 0;
}

int ftape_report_error(unsigned int *error,
		       qic117_cmd_t *command, int report)
{
	static const ftape_error ftape_errors[] = QIC117_ERRORS;
	int code;
	TRACE_FUN(ft_t_any);

	TRACE_CATCH(ftape_report_operation(&code, QIC_REPORT_ERROR_CODE, 16),);
	*error   = (unsigned int)(code & 0xff);
	*command = (qic117_cmd_t)((code>>8)&0xff);
	/*  remember hardware status, maybe useful for status ioctls
	 */
	ft_last_error.error.command = (__u8)*command;
	ft_last_error.error.error   = (__u8)*error;
	if (!report) {
		TRACE_EXIT 0;
	}
	if (*error == 0) {
		TRACE_ABORT(0, ft_t_info, "No error");
	}
	TRACE(ft_t_info, "errorcode: %d", *error);
	if (*error < NR_ITEMS(ftape_errors)) {
		TRACE(ft_t_noise, "%sFatal ERROR:",
		      (ftape_errors[*error].fatal ? "" : "Non-"));
		TRACE(ft_t_noise, "%s ...", ftape_errors[*error].message);
	} else {
		TRACE(ft_t_noise, "Unknown ERROR !");
	}
	if ((unsigned int)*command < NR_ITEMS(qic117_cmds) &&
	    qic117_cmds[*command].name != NULL) {
		TRACE(ft_t_noise, "... caused by command \'%s\'",
		      qic117_cmds[*command].name);
	} else {
		TRACE(ft_t_noise, "... caused by unknown command %d",
		      *command);
	}
	TRACE_EXIT 0;
}

int ftape_report_configuration(qic_model *model,
			       unsigned int *rate,
			       int *qic_std,
			       int *tape_len)
{
	int result;
	int config;
	int status;
	static const unsigned int qic_rates[ 4] = { 250, 2000, 500, 1000 };
	TRACE_FUN(ft_t_any);

	result = ftape_report_operation(&config,
					QIC_REPORT_DRIVE_CONFIGURATION, 8);
	if (result < 0) {
		ft_last_status.status.drive_config = (__u8)0x00;
		*model = prehistoric;
		*rate = 500;
		*qic_std = QIC_TAPE_QIC40;
		*tape_len = 205;
		TRACE_EXIT 0;
	} else {
		ft_last_status.status.drive_config = (__u8)(config & 0xff);
	}
	*rate = qic_rates[(config & QIC_CONFIG_RATE_MASK) >> QIC_CONFIG_RATE_SHIFT];
	result = ftape_report_operation(&status, QIC_REPORT_TAPE_STATUS, 8);
	if (result < 0) {
		ft_last_status.status.tape_status = (__u8)0x00;
		/* pre- QIC117 rev C spec. drive, QIC_CONFIG_80 bit is valid.
		 */
		*qic_std = (config & QIC_CONFIG_80) ?
			QIC_TAPE_QIC80 : QIC_TAPE_QIC40;
		/* ?? how's about 425ft tapes? */
		*tape_len = (config & QIC_CONFIG_LONG) ? 307 : 0;
		*model = pre_qic117c;
		result = 0;
	} else {
		ft_last_status.status.tape_status = (__u8)(status & 0xff);
		*model = post_qic117b;
		TRACE(ft_t_any, "report tape status result = %02x", status);
		/* post- QIC117 rev C spec. drive, QIC_CONFIG_80 bit is
		 * invalid. 
		 */
		switch (status & QIC_TAPE_STD_MASK) {
		case QIC_TAPE_QIC40:
		case QIC_TAPE_QIC80:
		case QIC_TAPE_QIC3020:
		case QIC_TAPE_QIC3010:
			*qic_std = status & QIC_TAPE_STD_MASK;
			break;
		default:
			*qic_std = -1;
			break;
		}
		switch (status & QIC_TAPE_LEN_MASK) {
		case QIC_TAPE_205FT:
			/* 205 or 425+ ft 550 Oe tape */
			*tape_len = 0;
			break;
		case QIC_TAPE_307FT:
			/* 307.5 ft 550 Oe Extended Length (XL) tape */
			*tape_len = 307;
			break;
		case QIC_TAPE_VARIABLE:
			/* Variable length 550 Oe tape */
			*tape_len = 0;
			break;
		case QIC_TAPE_1100FT:
			/* 1100 ft 550 Oe tape */
			*tape_len = 1100;
			break;
		case QIC_TAPE_FLEX:
			/* Variable length 900 Oe tape */
			*tape_len = 0;
			break;
		default:
			*tape_len = -1;
			break;
		}
		if (*qic_std == -1 || *tape_len == -1) {
			TRACE(ft_t_any,
			      "post qic-117b spec drive with unknown tape");
		}
		result = *tape_len == -1 ? -EIO : 0;
		if (status & QIC_TAPE_WIDE) {
			switch (*qic_std) {
			case QIC_TAPE_QIC80:
				TRACE(ft_t_info, "TR-1 tape detected");
				break;
			case QIC_TAPE_QIC3010:
				TRACE(ft_t_info, "TR-2 tape detected");
				break;
			case QIC_TAPE_QIC3020:
				TRACE(ft_t_info, "TR-3 tape detected");
				break;
			default:
				TRACE(ft_t_warn,
				      "Unknown Travan tape type detected");
				break;
			}
		}
	}
	TRACE_EXIT (result < 0) ? -EIO : 0;
}

static int ftape_report_rom_version(int *version)
{

	if (ftape_report_operation(version, QIC_REPORT_ROM_VERSION, 8) < 0) {
		return -EIO;
	} else {
		return 0;
	}
}

void ftape_report_vendor_id(unsigned int *id)
{
	int result;
	TRACE_FUN(ft_t_any);

	/* We'll try to get a vendor id from the drive.  First
	 * according to the QIC-117 spec, a 16-bit id is requested.
	 * If that fails we'll try an 8-bit version, otherwise we'll
	 * try an undocumented query.
	 */
	result = ftape_report_operation((int *) id, QIC_REPORT_VENDOR_ID, 16);
	if (result < 0) {
		result = ftape_report_operation((int *) id,
						QIC_REPORT_VENDOR_ID, 8);
		if (result < 0) {
			/* The following is an undocumented call found
			 * in the CMS code.
			 */
			result = ftape_report_operation((int *) id, 24, 8);
			if (result < 0) {
				*id = UNKNOWN_VENDOR;
			} else {
				TRACE(ft_t_noise, "got old 8 bit id: %04x",
				      *id);
				*id |= 0x20000;
			}
		} else {
			TRACE(ft_t_noise, "got 8 bit id: %04x", *id);
			*id |= 0x10000;
		}
	} else {
		TRACE(ft_t_noise, "got 16 bit id: %04x", *id);
	}
	if (*id == 0x0047) {
		int version;
		int sign;

		if (ftape_report_rom_version(&version) < 0) {
			TRACE(ft_t_bug, "report rom version failed");
			TRACE_EXIT;
		}
		TRACE(ft_t_noise, "CMS rom version: %d", version);
		ftape_command(QIC_ENTER_DIAGNOSTIC_1);
		ftape_command(QIC_ENTER_DIAGNOSTIC_1);
		diagnostic_mode = 1;
		if (ftape_report_operation(&sign, 9, 8) < 0) {
			unsigned int error;
			qic117_cmd_t command;

			ftape_report_error(&error, &command, 1);
			ftape_command(QIC_ENTER_PRIMARY_MODE);
			diagnostic_mode = 0;
			TRACE_EXIT;	/* failure ! */
		} else {
			TRACE(ft_t_noise, "CMS signature: %02x", sign);
		}
		if (sign == 0xa5) {
			result = ftape_report_operation(&sign, 37, 8);
			if (result < 0) {
				if (version >= 63) {
					*id = 0x8880;
					TRACE(ft_t_noise,
					      "This is an Iomega drive !");
				} else {
					*id = 0x0047;
					TRACE(ft_t_noise,
					      "This is a real CMS drive !");
				}
			} else {
				*id = 0x0047;
				TRACE(ft_t_noise, "CMS status: %d", sign);
			}
		} else {
			*id = UNKNOWN_VENDOR;
		}
		ftape_command(QIC_ENTER_PRIMARY_MODE);
		diagnostic_mode = 0;
	}
	TRACE_EXIT;
}

static int qic_rate_code(unsigned int rate)
{
	switch (rate) {
	case 250:
		return QIC_CONFIG_RATE_250;
	case 500:
		return QIC_CONFIG_RATE_500;
	case 1000:
		return QIC_CONFIG_RATE_1000;
	case 2000:
		return QIC_CONFIG_RATE_2000;
	default:
		return QIC_CONFIG_RATE_500;
	}
}

static int ftape_set_rate_test(unsigned int *max_rate)
{
	unsigned int error;
	qic117_cmd_t command;
	int status;
	int supported = 0;
	TRACE_FUN(ft_t_any);

	/*  Check if the drive does support the select rate command
	 *  by testing all different settings. If any one is accepted
	 *  we assume the command is supported, else not.
	 */
	for (*max_rate = 2000; *max_rate >= 250; *max_rate /= 2) {
		if (ftape_command(QIC_SELECT_RATE) < 0) {
			continue;
		}		
		if (ftape_parameter_wait(qic_rate_code(*max_rate),
					 1 * FT_SECOND, &status) < 0) {
			continue;
		}
		if (status & QIC_STATUS_ERROR) {
			ftape_report_error(&error, &command, 0);
			continue;
		}
		supported = 1; /* did accept a request */
		break;
	}
	TRACE(ft_t_noise, "Select Rate command is%s supported", 
	      supported ? "" : " not");
	TRACE_EXIT supported;
}

int ftape_set_data_rate(unsigned int new_rate /* Kbps */, unsigned int qic_std)
{
	int status;
	int result = 0;
	unsigned int data_rate = new_rate;
	static int supported;
	int rate_changed = 0;
	qic_model dummy_model;
	unsigned int dummy_qic_std, dummy_tape_len;
	TRACE_FUN(ft_t_any);

	if (ft_drive_max_rate == 0) { /* first time */
		supported = ftape_set_rate_test(&ft_drive_max_rate);
	}
	if (supported) {
		ftape_command(QIC_SELECT_RATE);
		result = ftape_parameter_wait(qic_rate_code(new_rate),
					      1 * FT_SECOND, &status);
		if (result >= 0 && !(status & QIC_STATUS_ERROR)) {
			rate_changed = 1;
		}
	}
	TRACE_CATCH(result = ftape_report_configuration(&dummy_model,
							&data_rate, 
							&dummy_qic_std,
							&dummy_tape_len),);
	if (data_rate != new_rate) {
		if (!supported) {
			TRACE(ft_t_warn, "Rate change not supported!");
		} else if (rate_changed) {
			TRACE(ft_t_warn, "Requested: %d, got %d",
			      new_rate, data_rate);
		} else {
			TRACE(ft_t_warn, "Rate change failed!");
		}
		result = -EINVAL;
	}
	/*
	 *  Set data rate and write precompensation as specified:
	 *
	 *            |  QIC-40/80  | QIC-3010/3020
	 *   rate     |   precomp   |    precomp
	 *  ----------+-------------+--------------
	 *  250 Kbps. |   250 ns.   |     0 ns.
	 *  500 Kbps. |   125 ns.   |     0 ns.
	 *    1 Mbps. |    42 ns.   |     0 ns.
	 *    2 Mbps  |      N/A    |     0 ns.
	 */
	if ((qic_std == QIC_TAPE_QIC40 && data_rate > 500) || 
	    (qic_std == QIC_TAPE_QIC80 && data_rate > 1000)) {
		TRACE_ABORT(-EINVAL,
			    ft_t_warn, "Datarate too high for QIC-mode");
	}
	TRACE_CATCH(fdc_set_data_rate(data_rate),_res = -EINVAL);
	ft_data_rate = data_rate;
	if (qic_std == QIC_TAPE_QIC40 || qic_std == QIC_TAPE_QIC80) {
		switch (data_rate) {
		case 250:
			fdc_set_write_precomp(250);
			break;
		default:
		case 500:
			fdc_set_write_precomp(125);
			break;
		case 1000:
			fdc_set_write_precomp(42);
			break;
		}
	} else {
		fdc_set_write_precomp(0);
	}
	TRACE_EXIT result;
}

/*  The next two functions are used to cope with excessive overrun errors
 */
int ftape_increase_threshold(void)
{
	TRACE_FUN(ft_t_flow);

	if (fdc.type < i82077 || ft_fdc_threshold >= 12) {
		TRACE_ABORT(-EIO, ft_t_err, "cannot increase fifo threshold");
	}
	if (fdc_fifo_threshold(++ft_fdc_threshold, NULL, NULL, NULL) < 0) {
		TRACE(ft_t_err, "cannot increase fifo threshold");
		ft_fdc_threshold --;
		fdc_reset();
	}
	TRACE(ft_t_info, "New FIFO threshold: %d", ft_fdc_threshold);
	TRACE_EXIT 0;
}

int ftape_half_data_rate(void)
{
	if (ft_data_rate < 500) {
		return -1;
	}
	if (ftape_set_data_rate(ft_data_rate / 2, ft_qic_std) < 0) {
		return -EIO;
	}
	ftape_calc_timeouts(ft_qic_std, ft_data_rate, ftape_tape_len);
	return 0;
}

/*      Seek the head to the specified track.
 */
int ftape_seek_head_to_track(unsigned int track)
{
	int status;
	TRACE_FUN(ft_t_any);

	ft_location.track = -1; /* remains set in case of error */
	if (track >= ft_tracks_per_tape) {
		TRACE_ABORT(-EINVAL, ft_t_bug, "track out of bounds");
	}
	TRACE(ft_t_flow, "seeking track %d", track);
	TRACE_CATCH(ftape_command(QIC_SEEK_HEAD_TO_TRACK),);
	TRACE_CATCH(ftape_parameter_wait(track, ftape_timeout.head_seek,
					 &status),);
	ft_location.track = track;
	ftape_might_be_off_track = 0;
	TRACE_EXIT 0;
}

int ftape_wakeup_drive(wake_up_types method)
{
	int status;
	int motor_on = 0;
	TRACE_FUN(ft_t_any);

	switch (method) {
	case wake_up_colorado:
		TRACE_CATCH(ftape_command(QIC_PHANTOM_SELECT),);
		TRACE_CATCH(ftape_parameter(0 /* ft_drive_sel ?? */),);
		break;
	case wake_up_mountain:
		TRACE_CATCH(ftape_command(QIC_SOFT_SELECT),);
		ftape_sleep(FT_MILLISECOND);	/* NEEDED */
		TRACE_CATCH(ftape_parameter(18),);
		break;
	case wake_up_insight:
		ftape_sleep(100 * FT_MILLISECOND);
		motor_on = 1;
		fdc_motor(motor_on);	/* enable is done by motor-on */
	case no_wake_up:
		break;
	default:
		TRACE_EXIT -ENODEV;	/* unknown wakeup method */
		break;
	}
	/*  If wakeup succeeded we shouldn't get an error here..
	 */
	TRACE_CATCH(ftape_report_raw_drive_status(&status),
		    if (motor_on) {
			    fdc_motor(0);
		    });
	TRACE_EXIT 0;
}

int ftape_put_drive_to_sleep(wake_up_types method)
{
	TRACE_FUN(ft_t_any);

	switch (method) {
	case wake_up_colorado:
		TRACE_CATCH(ftape_command(QIC_PHANTOM_DESELECT),);
		break;
	case wake_up_mountain:
		TRACE_CATCH(ftape_command(QIC_SOFT_DESELECT),);
		break;
	case wake_up_insight:
		fdc_motor(0);	/* enable is done by motor-on */
	case no_wake_up:	/* no wakeup / no sleep ! */
		break;
	default:
		TRACE_EXIT -ENODEV;	/* unknown wakeup method */
	}
	TRACE_EXIT 0;
}

int ftape_reset_drive(void)
{
	int result = 0;
	int status;
	unsigned int err_code;
	qic117_cmd_t err_command;
	int i;
	TRACE_FUN(ft_t_any);

	/*  We want to re-establish contact with our drive.  Fire a
	 *  number of reset commands (single step pulses) and pray for
	 *  success.
	 */
	for (i = 0; i < 2; ++i) {
		TRACE(ft_t_flow, "Resetting fdc");
		fdc_reset();
		ftape_sleep(10 * FT_MILLISECOND);
		TRACE(ft_t_flow, "Reset command to drive");
		result = ftape_command(QIC_RESET);
		if (result == 0) {
			ftape_sleep(1 * FT_SECOND); /*  drive not
						     *  accessible
						     *  during 1 second
						     */
			TRACE(ft_t_flow, "Re-selecting drive");

			/* Strange, the QIC-117 specs don't mention
			 * this but the drive gets deselected after a
			 * soft reset !  So we need to enable it
			 * again.
			 */
			if (ftape_wakeup_drive(ft_drive_type.wake_up) < 0) {
				TRACE(ft_t_err, "Wakeup failed !");
			}
			TRACE(ft_t_flow, "Waiting until drive gets ready");
			result= ftape_ready_wait(ftape_timeout.reset, &status);
			if (result == 0 && (status & QIC_STATUS_ERROR)) {
				result = ftape_report_error(&err_code,
							    &err_command, 1);
				if (result == 0 && err_code == 27) {
					/*  Okay, drive saw reset
					 *  command and responded as it
					 *  should
					 */
					break;
				} else {
					result = -EIO;
				}
			} else {
				result = -EIO;
			}
		}
		FT_SIGNAL_EXIT(_DONT_BLOCK);
	}
	if (result != 0) {
		TRACE(ft_t_err, "General failure to reset tape drive");
	} else {
		/*  Restore correct settings: keep original rate 
		 */
		ftape_set_data_rate(ft_data_rate, ft_qic_std);
	}
	ftape_init_drive_needed = 1;
	TRACE_EXIT result;
}