summaryrefslogblamecommitdiff
path: root/drivers/ide/ide-probe.c
blob: c1128ae5cd2f98319ee889b74fefd7e69916edd4 (plain) (tree)
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
















































                                                                               
                                  








































































































































































































































































































































































































































































































































































































































































                                                                                                                                  
                                            




                                                          
                                            






















































































































































































































                                                                                            
                                                                
























































                                                                             
 
                                                                               



































































                                                                           

                             















































                                                                            
                                                                         
                                                                            























































































































































































                                                                                            






















                                                             



                                                                    

















                                                






















                                                                              








































































































                                                                                        
                                                                                    





                                 
/*
 *  linux/drivers/ide/ide-probe.c	Version 1.11	Mar 05, 2003
 *
 *  Copyright (C) 1994-1998  Linus Torvalds & authors (see below)
 */

/*
 *  Mostly written by Mark Lord <mlord@pobox.com>
 *                and Gadi Oxman <gadio@netvision.net.il>
 *                and Andre Hedrick <andre@linux-ide.org>
 *
 *  See linux/MAINTAINERS for address of current maintainer.
 *
 * This is the IDE probe module, as evolved from hd.c and ide.c.
 *
 * Version 1.00		move drive probing code from ide.c to ide-probe.c
 * Version 1.01		fix compilation problem for m68k
 * Version 1.02		increase WAIT_PIDENTIFY to avoid CD-ROM locking at boot
 *			 by Andrea Arcangeli
 * Version 1.03		fix for (hwif->chipset == ide_4drives)
 * Version 1.04		fixed buggy treatments of known flash memory cards
 *
 * Version 1.05		fix for (hwif->chipset == ide_pdc4030)
 *			added ide6/7/8/9
 *			allowed for secondary flash card to be detectable
 *			 with new flag : drive->ata_flash : 1;
 * Version 1.06		stream line request queue and prep for cascade project.
 * Version 1.07		max_sect <= 255; slower disks would get behind and
 * 			then fall over when they get to 256.	Paul G.
 * Version 1.10		Update set for new IDE. drive->id is now always
 *			valid after probe time even with noprobe
 */

#undef REALLY_SLOW_IO		/* most systems can safely undef this */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/errno.h>
#include <linux/genhd.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/spinlock.h>
#include <linux/kmod.h>
#include <linux/pci.h>

#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/io.h>

/**
 *	generic_id		-	add a generic drive id
 *	@drive:	drive to make an ID block for
 *	
 *	Add a fake id field to the drive we are passed. This allows
 *	use to skip a ton of NULL checks (which people always miss) 
 *	and make drive properties unconditional outside of this file
 */
 
static void generic_id(ide_drive_t *drive)
{
	drive->id->cyls = drive->cyl;
	drive->id->heads = drive->head;
	drive->id->sectors = drive->sect;
	drive->id->cur_cyls = drive->cyl;
	drive->id->cur_heads = drive->head;
	drive->id->cur_sectors = drive->sect;
}

static void ide_disk_init_chs(ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;

	/* Extract geometry if we did not already have one for the drive */
	if (!drive->cyl || !drive->head || !drive->sect) {
		drive->cyl  = drive->bios_cyl  = id->cyls;
		drive->head = drive->bios_head = id->heads;
		drive->sect = drive->bios_sect = id->sectors;
	}

	/* Handle logical geometry translation by the drive */
	if ((id->field_valid & 1) && id->cur_cyls &&
	    id->cur_heads && (id->cur_heads <= 16) && id->cur_sectors) {
		drive->cyl  = id->cur_cyls;
		drive->head = id->cur_heads;
		drive->sect = id->cur_sectors;
	}

	/* Use physical geometry if what we have still makes no sense */
	if (drive->head > 16 && id->heads && id->heads <= 16) {
		drive->cyl  = id->cyls;
		drive->head = id->heads;
		drive->sect = id->sectors;
	}
}

static void ide_disk_init_mult_count(ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;

	drive->mult_count = 0;
	if (id->max_multsect) {
#ifdef CONFIG_IDEDISK_MULTI_MODE
		id->multsect = ((id->max_multsect/2) > 1) ? id->max_multsect : 0;
		id->multsect_valid = id->multsect ? 1 : 0;
		drive->mult_req = id->multsect_valid ? id->max_multsect : INITIAL_MULT_COUNT;
		drive->special.b.set_multmode = drive->mult_req ? 1 : 0;
#else	/* original, pre IDE-NFG, per request of AC */
		drive->mult_req = INITIAL_MULT_COUNT;
		if (drive->mult_req > id->max_multsect)
			drive->mult_req = id->max_multsect;
		if (drive->mult_req || ((id->multsect_valid & 1) && id->multsect))
			drive->special.b.set_multmode = 1;
#endif
	}
}

/**
 *	drive_is_flashcard	-	check for compact flash
 *	@drive: drive to check
 *
 *	CompactFlash cards and their brethern pretend to be removable
 *	hard disks, except:
 * 		(1) they never have a slave unit, and
 *		(2) they don't have doorlock mechanisms.
 *	This test catches them, and is invoked elsewhere when setting
 *	appropriate config bits.
 *
 *	FIXME: This treatment is probably applicable for *all* PCMCIA (PC CARD)
 *	devices, so in linux 2.3.x we should change this to just treat all
 *	PCMCIA  drives this way, and get rid of the model-name tests below
 *	(too big of an interface change for 2.4.x).
 *	At that time, we might also consider parameterizing the timeouts and
 *	retries, since these are MUCH faster than mechanical drives. -M.Lord
 */
 
static inline int drive_is_flashcard (ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;

	if (drive->removable) {
		if (id->config == 0x848a) return 1;	/* CompactFlash */
		if (!strncmp(id->model, "KODAK ATA_FLASH", 15)	/* Kodak */
		 || !strncmp(id->model, "Hitachi CV", 10)	/* Hitachi */
		 || !strncmp(id->model, "SunDisk SDCFB", 13)	/* old SanDisk */
		 || !strncmp(id->model, "SanDisk SDCFB", 13)	/* SanDisk */
		 || !strncmp(id->model, "HAGIWARA HPC", 12)	/* Hagiwara */
		 || !strncmp(id->model, "LEXAR ATA_FLASH", 15)	/* Lexar */
		 || !strncmp(id->model, "ATA_FLASH", 9))	/* Simple Tech */
		{
			return 1;	/* yes, it is a flash memory card */
		}
	}
	return 0;	/* no, it is not a flash memory card */
}

/**
 *	do_identify	-	identify a drive
 *	@drive: drive to identify 
 *	@cmd: command used
 *
 *	Called when we have issued a drive identify command to
 *	read and parse the results. This function is run with
 *	interrupts disabled. 
 */
 
static inline void do_identify (ide_drive_t *drive, u8 cmd)
{
	ide_hwif_t *hwif = HWIF(drive);
	int bswap = 1;
	struct hd_driveid *id;

	id = drive->id;
	/* read 512 bytes of id info */
	hwif->ata_input_data(drive, id, SECTOR_WORDS);

	drive->id_read = 1;
	local_irq_enable();
	ide_fix_driveid(id);

#if defined (CONFIG_SCSI_EATA_DMA) || defined (CONFIG_SCSI_EATA_PIO) || defined (CONFIG_SCSI_EATA)
	/*
	 * EATA SCSI controllers do a hardware ATA emulation:
	 * Ignore them if there is a driver for them available.
	 */
	if ((id->model[0] == 'P' && id->model[1] == 'M') ||
	    (id->model[0] == 'S' && id->model[1] == 'K')) {
		printk("%s: EATA SCSI HBA %.10s\n", drive->name, id->model);
		goto err_misc;
	}
#endif /* CONFIG_SCSI_EATA_DMA || CONFIG_SCSI_EATA_PIO */

	/*
	 *  WIN_IDENTIFY returns little-endian info,
	 *  WIN_PIDENTIFY *usually* returns little-endian info.
	 */
	if (cmd == WIN_PIDENTIFY) {
		if ((id->model[0] == 'N' && id->model[1] == 'E') /* NEC */
		 || (id->model[0] == 'F' && id->model[1] == 'X') /* Mitsumi */
		 || (id->model[0] == 'P' && id->model[1] == 'i'))/* Pioneer */
			/* Vertos drives may still be weird */
			bswap ^= 1;	
	}
	ide_fixstring(id->model,     sizeof(id->model),     bswap);
	ide_fixstring(id->fw_rev,    sizeof(id->fw_rev),    bswap);
	ide_fixstring(id->serial_no, sizeof(id->serial_no), bswap);

	if (strstr(id->model, "E X A B Y T E N E S T"))
		goto err_misc;

	/* we depend on this a lot! */
	id->model[sizeof(id->model)-1] = '\0';
	printk("%s: %s, ", drive->name, id->model);
	drive->present = 1;
	drive->dead = 0;

	/*
	 * Check for an ATAPI device
	 */
	if (cmd == WIN_PIDENTIFY) {
		u8 type = (id->config >> 8) & 0x1f;
		printk("ATAPI ");
		switch (type) {
			case ide_floppy:
				if (!strstr(id->model, "CD-ROM")) {
					if (!strstr(id->model, "oppy") &&
					    !strstr(id->model, "poyp") &&
					    !strstr(id->model, "ZIP"))
						printk("cdrom or floppy?, assuming ");
					if (drive->media != ide_cdrom) {
						printk ("FLOPPY");
						drive->removable = 1;
						break;
					}
				}
				/* Early cdrom models used zero */
				type = ide_cdrom;
			case ide_cdrom:
				drive->removable = 1;
#ifdef CONFIG_PPC
				/* kludge for Apple PowerBook internal zip */
				if (!strstr(id->model, "CD-ROM") &&
				    strstr(id->model, "ZIP")) {
					printk ("FLOPPY");
					type = ide_floppy;
					break;
				}
#endif
				printk ("CD/DVD-ROM");
				break;
			case ide_tape:
				printk ("TAPE");
				break;
			case ide_optical:
				printk ("OPTICAL");
				drive->removable = 1;
				break;
			default:
				printk("UNKNOWN (type %d)", type);
				break;
		}
		printk (" drive\n");
		drive->media = type;
		/* an ATAPI device ignores DRDY */
		drive->ready_stat = 0;
		return;
	}

	/*
	 * Not an ATAPI device: looks like a "regular" hard disk
	 */
	if (id->config & (1<<7))
		drive->removable = 1;

	if (drive_is_flashcard(drive))
		drive->is_flash = 1;
	drive->media = ide_disk;
	printk("%s DISK drive\n", (drive->is_flash) ? "CFA" : "ATA" );
	QUIRK_LIST(drive);
	return;

err_misc:
	kfree(id);
	drive->present = 0;
	return;
}

/**
 *	actual_try_to_identify	-	send ata/atapi identify
 *	@drive: drive to identify
 *	@cmd: command to use
 *
 *	try_to_identify() sends an ATA(PI) IDENTIFY request to a drive
 *	and waits for a response.  It also monitors irqs while this is
 *	happening, in hope of automatically determining which one is
 *	being used by the interface.
 *
 *	Returns:	0  device was identified
 *			1  device timed-out (no response to identify request)
 *			2  device aborted the command (refused to identify itself)
 */

static int actual_try_to_identify (ide_drive_t *drive, u8 cmd)
{
	ide_hwif_t *hwif = HWIF(drive);
	int rc;
	unsigned long hd_status;
	unsigned long timeout;
	u8 s = 0, a = 0;

	/* take a deep breath */
	msleep(50);

	if (IDE_CONTROL_REG) {
		a = hwif->INB(IDE_ALTSTATUS_REG);
		s = hwif->INB(IDE_STATUS_REG);
		if ((a ^ s) & ~INDEX_STAT) {
			printk(KERN_INFO "%s: probing with STATUS(0x%02x) instead of "
				"ALTSTATUS(0x%02x)\n", drive->name, s, a);
			/* ancient Seagate drives, broken interfaces */
			hd_status = IDE_STATUS_REG;
		} else {
			/* use non-intrusive polling */
			hd_status = IDE_ALTSTATUS_REG;
		}
	} else
		hd_status = IDE_STATUS_REG;

	/* set features register for atapi
	 * identify command to be sure of reply
	 */
	if ((cmd == WIN_PIDENTIFY))
		/* disable dma & overlap */
		hwif->OUTB(0, IDE_FEATURE_REG);

	/* ask drive for ID */
	hwif->OUTB(cmd, IDE_COMMAND_REG);

	timeout = ((cmd == WIN_IDENTIFY) ? WAIT_WORSTCASE : WAIT_PIDENTIFY) / 2;
	timeout += jiffies;
	do {
		if (time_after(jiffies, timeout)) {
			/* drive timed-out */
			return 1;
		}
		/* give drive a breather */
		msleep(50);
	} while ((hwif->INB(hd_status)) & BUSY_STAT);

	/* wait for IRQ and DRQ_STAT */
	msleep(50);
	if (OK_STAT((hwif->INB(IDE_STATUS_REG)), DRQ_STAT, BAD_R_STAT)) {
		unsigned long flags;

		/* local CPU only; some systems need this */
		local_irq_save(flags);
		/* drive returned ID */
		do_identify(drive, cmd);
		/* drive responded with ID */
		rc = 0;
		/* clear drive IRQ */
		(void) hwif->INB(IDE_STATUS_REG);
		local_irq_restore(flags);
	} else {
		/* drive refused ID */
		rc = 2;
	}
	return rc;
}

/**
 *	try_to_identify	-	try to identify a drive
 *	@drive: drive to probe
 *	@cmd: command to use
 *
 *	Issue the identify command and then do IRQ probing to
 *	complete the identification when needed by finding the
 *	IRQ the drive is attached to
 */
 
static int try_to_identify (ide_drive_t *drive, u8 cmd)
{
	ide_hwif_t *hwif = HWIF(drive);
	int retval;
	int autoprobe = 0;
	unsigned long cookie = 0;

	/*
	 * Disable device irq unless we need to
	 * probe for it. Otherwise we'll get spurious
	 * interrupts during the identify-phase that
	 * the irq handler isn't expecting.
	 */
	if (IDE_CONTROL_REG) {
		u8 ctl = drive->ctl | 2;
		if (!hwif->irq) {
			autoprobe = 1;
			cookie = probe_irq_on();
			/* enable device irq */
			ctl &= ~2;
		}
		hwif->OUTB(ctl, IDE_CONTROL_REG);
	}

	retval = actual_try_to_identify(drive, cmd);

	if (autoprobe) {
		int irq;
		/* mask device irq */
		hwif->OUTB(drive->ctl|2, IDE_CONTROL_REG);
		/* clear drive IRQ */
		(void) hwif->INB(IDE_STATUS_REG);
		udelay(5);
		irq = probe_irq_off(cookie);
		if (!hwif->irq) {
			if (irq > 0) {
				hwif->irq = irq;
			} else {
				/* Mmmm.. multiple IRQs..
				 * don't know which was ours
				 */
				printk("%s: IRQ probe failed (0x%lx)\n",
					drive->name, cookie);
			}
		}
	}
	return retval;
}


/**
 *	do_probe		-	probe an IDE device
 *	@drive: drive to probe
 *	@cmd: command to use
 *
 *	do_probe() has the difficult job of finding a drive if it exists,
 *	without getting hung up if it doesn't exist, without trampling on
 *	ethernet cards, and without leaving any IRQs dangling to haunt us later.
 *
 *	If a drive is "known" to exist (from CMOS or kernel parameters),
 *	but does not respond right away, the probe will "hang in there"
 *	for the maximum wait time (about 30 seconds), otherwise it will
 *	exit much more quickly.
 *
 * Returns:	0  device was identified
 *		1  device timed-out (no response to identify request)
 *		2  device aborted the command (refused to identify itself)
 *		3  bad status from device (possible for ATAPI drives)
 *		4  probe was not attempted because failure was obvious
 */

static int do_probe (ide_drive_t *drive, u8 cmd)
{
	int rc;
	ide_hwif_t *hwif = HWIF(drive);

	if (drive->present) {
		/* avoid waiting for inappropriate probes */
		if ((drive->media != ide_disk) && (cmd == WIN_IDENTIFY))
			return 4;
	}
#ifdef DEBUG
	printk("probing for %s: present=%d, media=%d, probetype=%s\n",
		drive->name, drive->present, drive->media,
		(cmd == WIN_IDENTIFY) ? "ATA" : "ATAPI");
#endif

	/* needed for some systems
	 * (e.g. crw9624 as drive0 with disk as slave)
	 */
	msleep(50);
	SELECT_DRIVE(drive);
	msleep(50);
	if (hwif->INB(IDE_SELECT_REG) != drive->select.all && !drive->present) {
		if (drive->select.b.unit != 0) {
			/* exit with drive0 selected */
			SELECT_DRIVE(&hwif->drives[0]);
			/* allow BUSY_STAT to assert & clear */
			msleep(50);
		}
		/* no i/f present: mmm.. this should be a 4 -ml */
		return 3;
	}

	if (OK_STAT((hwif->INB(IDE_STATUS_REG)), READY_STAT, BUSY_STAT) ||
	    drive->present || cmd == WIN_PIDENTIFY) {
		/* send cmd and wait */
		if ((rc = try_to_identify(drive, cmd))) {
			/* failed: try again */
			rc = try_to_identify(drive,cmd);
		}
		if (hwif->INB(IDE_STATUS_REG) == (BUSY_STAT|READY_STAT))
			return 4;

		if ((rc == 1 && cmd == WIN_PIDENTIFY) &&
			((drive->autotune == IDE_TUNE_DEFAULT) ||
			(drive->autotune == IDE_TUNE_AUTO))) {
			unsigned long timeout;
			printk("%s: no response (status = 0x%02x), "
				"resetting drive\n", drive->name,
				hwif->INB(IDE_STATUS_REG));
			msleep(50);
			hwif->OUTB(drive->select.all, IDE_SELECT_REG);
			msleep(50);
			hwif->OUTB(WIN_SRST, IDE_COMMAND_REG);
			timeout = jiffies;
			while (((hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) &&
			       time_before(jiffies, timeout + WAIT_WORSTCASE))
				msleep(50);
			rc = try_to_identify(drive, cmd);
		}
		if (rc == 1)
			printk("%s: no response (status = 0x%02x)\n",
				drive->name, hwif->INB(IDE_STATUS_REG));
		/* ensure drive irq is clear */
		(void) hwif->INB(IDE_STATUS_REG);
	} else {
		/* not present or maybe ATAPI */
		rc = 3;
	}
	if (drive->select.b.unit != 0) {
		/* exit with drive0 selected */
		SELECT_DRIVE(&hwif->drives[0]);
		msleep(50);
		/* ensure drive irq is clear */
		(void) hwif->INB(IDE_STATUS_REG);
	}
	return rc;
}

/*
 *
 */
static void enable_nest (ide_drive_t *drive)
{
	ide_hwif_t *hwif = HWIF(drive);
	unsigned long timeout;

	printk("%s: enabling %s -- ", hwif->name, drive->id->model);
	SELECT_DRIVE(drive);
	msleep(50);
	hwif->OUTB(EXABYTE_ENABLE_NEST, IDE_COMMAND_REG);
	timeout = jiffies + WAIT_WORSTCASE;
	do {
		if (time_after(jiffies, timeout)) {
			printk("failed (timeout)\n");
			return;
		}
		msleep(50);
	} while ((hwif->INB(IDE_STATUS_REG)) & BUSY_STAT);

	msleep(50);

	if (!OK_STAT((hwif->INB(IDE_STATUS_REG)), 0, BAD_STAT)) {
		printk("failed (status = 0x%02x)\n", hwif->INB(IDE_STATUS_REG));
	} else {
		printk("success\n");
	}

	/* if !(success||timed-out) */
	if (do_probe(drive, WIN_IDENTIFY) >= 2) {
		/* look for ATAPI device */
		(void) do_probe(drive, WIN_PIDENTIFY);
	}
}

/**
 *	probe_for_drives	-	upper level drive probe
 *	@drive: drive to probe for
 *
 *	probe_for_drive() tests for existence of a given drive using do_probe()
 *	and presents things to the user as needed.
 *
 *	Returns:	0  no device was found
 *			1  device was found (note: drive->present might
 *			   still be 0)
 */
 
static inline u8 probe_for_drive (ide_drive_t *drive)
{
	/*
	 *	In order to keep things simple we have an id
	 *	block for all drives at all times. If the device
	 *	is pre ATA or refuses ATA/ATAPI identify we
	 *	will add faked data to this.
	 *
	 *	Also note that 0 everywhere means "can't do X"
	 */
 
	drive->id = kmalloc(SECTOR_WORDS *4, GFP_KERNEL);
	drive->id_read = 0;
	if(drive->id == NULL)
	{
		printk(KERN_ERR "ide: out of memory for id data.\n");
		return 0;
	}
	memset(drive->id, 0, SECTOR_WORDS * 4);
	strcpy(drive->id->model, "UNKNOWN");
	
	/* skip probing? */
	if (!drive->noprobe)
	{
		/* if !(success||timed-out) */
		if (do_probe(drive, WIN_IDENTIFY) >= 2) {
			/* look for ATAPI device */
			(void) do_probe(drive, WIN_PIDENTIFY);
		}
		if (strstr(drive->id->model, "E X A B Y T E N E S T"))
			enable_nest(drive);
		if (!drive->present)
			/* drive not found */
			return 0;
	
		/* identification failed? */
		if (!drive->id_read) {
			if (drive->media == ide_disk) {
				printk(KERN_INFO "%s: non-IDE drive, CHS=%d/%d/%d\n",
					drive->name, drive->cyl,
					drive->head, drive->sect);
			} else if (drive->media == ide_cdrom) {
				printk(KERN_INFO "%s: ATAPI cdrom (?)\n", drive->name);
			} else {
				/* nuke it */
				printk(KERN_WARNING "%s: Unknown device on bus refused identification. Ignoring.\n", drive->name);
				drive->present = 0;
			}
		}
		/* drive was found */
	}
	if(!drive->present)
		return 0;
	/* The drive wasn't being helpful. Add generic info only */
	if (drive->id_read == 0) {
		generic_id(drive);
		return 1;
	}

	if (drive->media == ide_disk) {
		ide_disk_init_chs(drive);
		ide_disk_init_mult_count(drive);
	}

	return drive->present;
}

static void hwif_release_dev (struct device *dev)
{
	ide_hwif_t *hwif = container_of(dev, ide_hwif_t, gendev);

	up(&hwif->gendev_rel_sem);
}

static void hwif_register (ide_hwif_t *hwif)
{
	/* register with global device tree */
	strlcpy(hwif->gendev.bus_id,hwif->name,BUS_ID_SIZE);
	hwif->gendev.driver_data = hwif;
	if (hwif->gendev.parent == NULL) {
		if (hwif->pci_dev)
			hwif->gendev.parent = &hwif->pci_dev->dev;
		else
			/* Would like to do = &device_legacy */
			hwif->gendev.parent = NULL;
	}
	hwif->gendev.release = hwif_release_dev;
	device_register(&hwif->gendev);
}

static int wait_hwif_ready(ide_hwif_t *hwif)
{
	int rc;

	printk(KERN_DEBUG "Probing IDE interface %s...\n", hwif->name);

	/* Let HW settle down a bit from whatever init state we
	 * come from */
	mdelay(2);

	/* Wait for BSY bit to go away, spec timeout is 30 seconds,
	 * I know of at least one disk who takes 31 seconds, I use 35
	 * here to be safe
	 */
	rc = ide_wait_not_busy(hwif, 35000);
	if (rc)
		return rc;

	/* Now make sure both master & slave are ready */
	SELECT_DRIVE(&hwif->drives[0]);
	hwif->OUTB(8, hwif->io_ports[IDE_CONTROL_OFFSET]);
	mdelay(2);
	rc = ide_wait_not_busy(hwif, 35000);
	if (rc)
		return rc;
	SELECT_DRIVE(&hwif->drives[1]);
	hwif->OUTB(8, hwif->io_ports[IDE_CONTROL_OFFSET]);
	mdelay(2);
	rc = ide_wait_not_busy(hwif, 35000);

	/* Exit function with master reselected (let's be sane) */
	SELECT_DRIVE(&hwif->drives[0]);
	
	return rc;
}

/**
 *	ide_undecoded_slave	-	look for bad CF adapters
 *	@hwif: interface
 *
 *	Analyse the drives on the interface and attempt to decide if we
 *	have the same drive viewed twice. This occurs with crap CF adapters
 *	and PCMCIA sometimes.
 */

void ide_undecoded_slave(ide_hwif_t *hwif)
{
	ide_drive_t *drive0 = &hwif->drives[0];
	ide_drive_t *drive1 = &hwif->drives[1];

	if (drive0->present == 0 || drive1->present == 0)
		return;

	/* If the models don't match they are not the same product */
	if (strcmp(drive0->id->model, drive1->id->model))
		return;

	/* Serial numbers do not match */
	if (strncmp(drive0->id->serial_no, drive1->id->serial_no, 20))
		return;

	/* No serial number, thankfully very rare for CF */
	if (drive0->id->serial_no[0] == 0)
		return;

	/* Appears to be an IDE flash adapter with decode bugs */
	printk(KERN_WARNING "ide-probe: ignoring undecoded slave\n");

	drive1->present = 0;
}

EXPORT_SYMBOL_GPL(ide_undecoded_slave);

/*
 * This routine only knows how to look for drive units 0 and 1
 * on an interface, so any setting of MAX_DRIVES > 2 won't work here.
 */
static void probe_hwif(ide_hwif_t *hwif)
{
	unsigned int unit;
	unsigned long flags;
	unsigned int irqd;

	if (hwif->noprobe)
		return;

	if ((hwif->chipset != ide_4drives || !hwif->mate || !hwif->mate->present) &&
	    (ide_hwif_request_regions(hwif))) {
		u16 msgout = 0;
		for (unit = 0; unit < MAX_DRIVES; ++unit) {
			ide_drive_t *drive = &hwif->drives[unit];
			if (drive->present) {
				drive->present = 0;
				printk(KERN_ERR "%s: ERROR, PORTS ALREADY IN USE\n",
					drive->name);
				msgout = 1;
			}
		}
		if (!msgout)
			printk(KERN_ERR "%s: ports already in use, skipping probe\n",
				hwif->name);
		return;	
	}

	/*
	 * We must always disable IRQ, as probe_for_drive will assert IRQ, but
	 * we'll install our IRQ driver much later...
	 */
	irqd = hwif->irq;
	if (irqd)
		disable_irq(hwif->irq);

	local_irq_set(flags);

	/* This is needed on some PPCs and a bunch of BIOS-less embedded
	 * platforms. Typical cases are:
	 * 
	 *  - The firmware hard reset the disk before booting the kernel,
	 *    the drive is still doing it's poweron-reset sequence, that
	 *    can take up to 30 seconds
	 *  - The firmware does nothing (or no firmware), the device is
	 *    still in POST state (same as above actually).
	 *  - Some CD/DVD/Writer combo drives tend to drive the bus during
	 *    their reset sequence even when they are non-selected slave
	 *    devices, thus preventing discovery of the main HD
	 *    
	 *  Doing this wait-for-busy should not harm any existing configuration
	 *  (at least things won't be worse than what current code does, that
	 *  is blindly go & talk to the drive) and fix some issues like the
	 *  above.
	 *  
	 *  BenH.
	 */
	if (wait_hwif_ready(hwif) == -EBUSY)
		printk(KERN_DEBUG "%s: Wait for ready failed before probe !\n", hwif->name);

	/*
	 * Second drive should only exist if first drive was found,
	 * but a lot of cdrom drives are configured as single slaves.
	 */
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];
		drive->dn = (hwif->channel ? 2 : 0) + unit;
		(void) probe_for_drive(drive);
		if (drive->present && !hwif->present) {
			hwif->present = 1;
			if (hwif->chipset != ide_4drives ||
			    !hwif->mate || 
			    !hwif->mate->present) {
				hwif_register(hwif);
			}
		}
	}
	if (hwif->io_ports[IDE_CONTROL_OFFSET] && hwif->reset) {
		unsigned long timeout = jiffies + WAIT_WORSTCASE;
		u8 stat;

		printk(KERN_WARNING "%s: reset\n", hwif->name);
		hwif->OUTB(12, hwif->io_ports[IDE_CONTROL_OFFSET]);
		udelay(10);
		hwif->OUTB(8, hwif->io_ports[IDE_CONTROL_OFFSET]);
		do {
			msleep(50);
			stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
		} while ((stat & BUSY_STAT) && time_after(timeout, jiffies));

	}
	local_irq_restore(flags);
	/*
	 * Use cached IRQ number. It might be (and is...) changed by probe
	 * code above
	 */
	if (irqd)
		enable_irq(irqd);

	if (!hwif->present) {
		ide_hwif_release_regions(hwif);
		return;
	}

	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];

		if (drive->present) {
			if (hwif->tuneproc != NULL && 
				drive->autotune == IDE_TUNE_AUTO)
				/* auto-tune PIO mode */
				hwif->tuneproc(drive, 255);

			if (drive->autotune != IDE_TUNE_DEFAULT &&
			    drive->autotune != IDE_TUNE_AUTO)
				continue;

			drive->nice1 = 1;

			/*
			 * MAJOR HACK BARF :-/
			 *
			 * FIXME: chipsets own this cruft!
			 */
			/*
			 * Move here to prevent module loading clashing.
			 */
	//		drive->autodma = hwif->autodma;
			if (hwif->ide_dma_check) {
				/*
				 * Force DMAing for the beginning of the check.
				 * Some chipsets appear to do interesting
				 * things, if not checked and cleared.
				 *   PARANOIA!!!
				 */
				hwif->ide_dma_off_quietly(drive);
#ifdef CONFIG_IDEDMA_ONLYDISK
				if (drive->media == ide_disk)
#endif
					hwif->ide_dma_check(drive);
			}
		}
	}
}

static int hwif_init(ide_hwif_t *hwif);

int probe_hwif_init_with_fixup(ide_hwif_t *hwif, void (*fixup)(ide_hwif_t *hwif))
{
	probe_hwif(hwif);

	if (fixup)
		fixup(hwif);

	if (!hwif_init(hwif)) {
		printk(KERN_INFO "%s: failed to initialize IDE interface\n",
				 hwif->name);
		return -1;
	}

	if (hwif->present) {
		u16 unit = 0;
		for (unit = 0; unit < MAX_DRIVES; ++unit) {
			ide_drive_t *drive = &hwif->drives[unit];
			/* For now don't attach absent drives, we may
			   want them on default or a new "empty" class
			   for hotplug reprobing ? */
			if (drive->present) {
				device_register(&drive->gendev);
			}
		}
	}
	return 0;
}

int probe_hwif_init(ide_hwif_t *hwif)
{
	return probe_hwif_init_with_fixup(hwif, NULL);
}

EXPORT_SYMBOL(probe_hwif_init);

#if MAX_HWIFS > 1
/*
 * save_match() is used to simplify logic in init_irq() below.
 *
 * A loophole here is that we may not know about a particular
 * hwif's irq until after that hwif is actually probed/initialized..
 * This could be a problem for the case where an hwif is on a
 * dual interface that requires serialization (eg. cmd640) and another
 * hwif using one of the same irqs is initialized beforehand.
 *
 * This routine detects and reports such situations, but does not fix them.
 */
static void save_match(ide_hwif_t *hwif, ide_hwif_t *new, ide_hwif_t **match)
{
	ide_hwif_t *m = *match;

	if (m && m->hwgroup && m->hwgroup != new->hwgroup) {
		if (!new->hwgroup)
			return;
		printk("%s: potential irq problem with %s and %s\n",
			hwif->name, new->name, m->name);
	}
	if (!m || m->irq != hwif->irq) /* don't undo a prior perfect match */
		*match = new;
}
#endif /* MAX_HWIFS > 1 */

/*
 * init request queue
 */
static int ide_init_queue(ide_drive_t *drive)
{
	request_queue_t *q;
	ide_hwif_t *hwif = HWIF(drive);
	int max_sectors = 256;
	int max_sg_entries = PRD_ENTRIES;

	/*
	 *	Our default set up assumes the normal IDE case,
	 *	that is 64K segmenting, standard PRD setup
	 *	and LBA28. Some drivers then impose their own
	 *	limits and LBA48 we could raise it but as yet
	 *	do not.
	 */

	q = blk_init_queue_node(do_ide_request, &ide_lock, hwif_to_node(hwif));
	if (!q)
		return 1;

	q->queuedata = drive;
	blk_queue_segment_boundary(q, 0xffff);

	if (!hwif->rqsize) {
		if (hwif->no_lba48 || hwif->no_lba48_dma)
			hwif->rqsize = 256;
		else
			hwif->rqsize = 65536;
	}
	if (hwif->rqsize < max_sectors)
		max_sectors = hwif->rqsize;
	blk_queue_max_sectors(q, max_sectors);

#ifdef CONFIG_PCI
	/* When we have an IOMMU, we may have a problem where pci_map_sg()
	 * creates segments that don't completely match our boundary
	 * requirements and thus need to be broken up again. Because it
	 * doesn't align properly either, we may actually have to break up
	 * to more segments than what was we got in the first place, a max
	 * worst case is twice as many.
	 * This will be fixed once we teach pci_map_sg() about our boundary
	 * requirements, hopefully soon. *FIXME*
	 */
	if (!PCI_DMA_BUS_IS_PHYS)
		max_sg_entries >>= 1;
#endif /* CONFIG_PCI */

	blk_queue_max_hw_segments(q, max_sg_entries);
	blk_queue_max_phys_segments(q, max_sg_entries);

	/* assign drive queue */
	drive->queue = q;

	/* needs drive->queue to be set */
	ide_toggle_bounce(drive, 1);

	/* enable led activity for disk drives only */
	if (drive->media == ide_disk && hwif->led_act)
		blk_queue_activity_fn(q, hwif->led_act, drive);

	return 0;
}

/*
 * This routine sets up the irq for an ide interface, and creates a new
 * hwgroup for the irq/hwif if none was previously assigned.
 *
 * Much of the code is for correctly detecting/handling irq sharing
 * and irq serialization situations.  This is somewhat complex because
 * it handles static as well as dynamic (PCMCIA) IDE interfaces.
 *
 * The SA_INTERRUPT in sa_flags means ide_intr() is always entered with
 * interrupts completely disabled.  This can be bad for interrupt latency,
 * but anything else has led to problems on some machines.  We re-enable
 * interrupts as much as we can safely do in most places.
 */
static int init_irq (ide_hwif_t *hwif)
{
	unsigned int index;
	ide_hwgroup_t *hwgroup;
	ide_hwif_t *match = NULL;


	BUG_ON(in_interrupt());
	BUG_ON(irqs_disabled());	
	BUG_ON(hwif == NULL);

	down(&ide_cfg_sem);
	hwif->hwgroup = NULL;
#if MAX_HWIFS > 1
	/*
	 * Group up with any other hwifs that share our irq(s).
	 */
	for (index = 0; index < MAX_HWIFS; index++) {
		ide_hwif_t *h = &ide_hwifs[index];
		if (h->hwgroup) {  /* scan only initialized hwif's */
			if (hwif->irq == h->irq) {
				hwif->sharing_irq = h->sharing_irq = 1;
				if (hwif->chipset != ide_pci ||
				    h->chipset != ide_pci) {
					save_match(hwif, h, &match);
				}
			}
			if (hwif->serialized) {
				if (hwif->mate && hwif->mate->irq == h->irq)
					save_match(hwif, h, &match);
			}
			if (h->serialized) {
				if (h->mate && hwif->irq == h->mate->irq)
					save_match(hwif, h, &match);
			}
		}
	}
#endif /* MAX_HWIFS > 1 */
	/*
	 * If we are still without a hwgroup, then form a new one
	 */
	if (match) {
		hwgroup = match->hwgroup;
		hwif->hwgroup = hwgroup;
		/*
		 * Link us into the hwgroup.
		 * This must be done early, do ensure that unexpected_intr
		 * can find the hwif and prevent irq storms.
		 * No drives are attached to the new hwif, choose_drive
		 * can't do anything stupid (yet).
		 * Add ourself as the 2nd entry to the hwgroup->hwif
		 * linked list, the first entry is the hwif that owns
		 * hwgroup->handler - do not change that.
		 */
		spin_lock_irq(&ide_lock);
		hwif->next = hwgroup->hwif->next;
		hwgroup->hwif->next = hwif;
		spin_unlock_irq(&ide_lock);
	} else {
		hwgroup = kmalloc_node(sizeof(ide_hwgroup_t), GFP_KERNEL,
					hwif_to_node(hwif->drives[0].hwif));
		if (!hwgroup)
	       		goto out_up;

		hwif->hwgroup = hwgroup;

		memset(hwgroup, 0, sizeof(ide_hwgroup_t));
		hwgroup->hwif     = hwif->next = hwif;
		hwgroup->rq       = NULL;
		hwgroup->handler  = NULL;
		hwgroup->drive    = NULL;
		hwgroup->busy     = 0;
		init_timer(&hwgroup->timer);
		hwgroup->timer.function = &ide_timer_expiry;
		hwgroup->timer.data = (unsigned long) hwgroup;
	}

	/*
	 * Allocate the irq, if not already obtained for another hwif
	 */
	if (!match || match->irq != hwif->irq) {
		int sa = SA_INTERRUPT;
#if defined(__mc68000__) || defined(CONFIG_APUS)
		sa = SA_SHIRQ;
#endif /* __mc68000__ || CONFIG_APUS */

		if (IDE_CHIPSET_IS_PCI(hwif->chipset)) {
			sa = SA_SHIRQ;
#ifndef CONFIG_IDEPCI_SHARE_IRQ
			sa |= SA_INTERRUPT;
#endif /* CONFIG_IDEPCI_SHARE_IRQ */
		}

		if (hwif->io_ports[IDE_CONTROL_OFFSET])
			/* clear nIEN */
			hwif->OUTB(0x08, hwif->io_ports[IDE_CONTROL_OFFSET]);

		if (request_irq(hwif->irq,&ide_intr,sa,hwif->name,hwgroup))
	       		goto out_unlink;
	}

	/*
	 * For any present drive:
	 * - allocate the block device queue
	 * - link drive into the hwgroup
	 */
	for (index = 0; index < MAX_DRIVES; ++index) {
		ide_drive_t *drive = &hwif->drives[index];
		if (!drive->present)
			continue;
		if (ide_init_queue(drive)) {
			printk(KERN_ERR "ide: failed to init %s\n",drive->name);
			continue;
		}
		spin_lock_irq(&ide_lock);
		if (!hwgroup->drive) {
			/* first drive for hwgroup. */
			drive->next = drive;
			hwgroup->drive = drive;
			hwgroup->hwif = HWIF(hwgroup->drive);
		} else {
			drive->next = hwgroup->drive->next;
			hwgroup->drive->next = drive;
		}
		spin_unlock_irq(&ide_lock);
	}

#if !defined(__mc68000__) && !defined(CONFIG_APUS) && !defined(__sparc__)
	printk("%s at 0x%03lx-0x%03lx,0x%03lx on irq %d", hwif->name,
		hwif->io_ports[IDE_DATA_OFFSET],
		hwif->io_ports[IDE_DATA_OFFSET]+7,
		hwif->io_ports[IDE_CONTROL_OFFSET], hwif->irq);
#elif defined(__sparc__)
	printk("%s at 0x%03lx-0x%03lx,0x%03lx on irq %s", hwif->name,
		hwif->io_ports[IDE_DATA_OFFSET],
		hwif->io_ports[IDE_DATA_OFFSET]+7,
		hwif->io_ports[IDE_CONTROL_OFFSET], __irq_itoa(hwif->irq));
#else
	printk("%s at 0x%08lx on irq %d", hwif->name,
		hwif->io_ports[IDE_DATA_OFFSET], hwif->irq);
#endif /* __mc68000__ && CONFIG_APUS */
	if (match)
		printk(" (%sed with %s)",
			hwif->sharing_irq ? "shar" : "serializ", match->name);
	printk("\n");
	up(&ide_cfg_sem);
	return 0;
out_unlink:
	spin_lock_irq(&ide_lock);
	if (hwif->next == hwif) {
		BUG_ON(match);
		BUG_ON(hwgroup->hwif != hwif);
		kfree(hwgroup);
	} else {
		ide_hwif_t *g;
		g = hwgroup->hwif;
		while (g->next != hwif)
			g = g->next;
		g->next = hwif->next;
		if (hwgroup->hwif == hwif) {
			/* Impossible. */
			printk(KERN_ERR "Duh. Uninitialized hwif listed as active hwif.\n");
			hwgroup->hwif = g;
		}
		BUG_ON(hwgroup->hwif == hwif);
	}
	spin_unlock_irq(&ide_lock);
out_up:
	up(&ide_cfg_sem);
	return 1;
}

static int ata_lock(dev_t dev, void *data)
{
	/* FIXME: we want to pin hwif down */
	return 0;
}

static struct kobject *ata_probe(dev_t dev, int *part, void *data)
{
	ide_hwif_t *hwif = data;
	int unit = *part >> PARTN_BITS;
	ide_drive_t *drive = &hwif->drives[unit];
	if (!drive->present)
		return NULL;

	if (drive->media == ide_disk)
		request_module("ide-disk");
	if (drive->scsi)
		request_module("ide-scsi");
	if (drive->media == ide_cdrom || drive->media == ide_optical)
		request_module("ide-cd");
	if (drive->media == ide_tape)
		request_module("ide-tape");
	if (drive->media == ide_floppy)
		request_module("ide-floppy");

	return NULL;
}

static struct kobject *exact_match(dev_t dev, int *part, void *data)
{
	struct gendisk *p = data;
	*part &= (1 << PARTN_BITS) - 1;
	return &p->kobj;
}

static int exact_lock(dev_t dev, void *data)
{
	struct gendisk *p = data;

	if (!get_disk(p))
		return -1;
	return 0;
}

void ide_register_region(struct gendisk *disk)
{
	blk_register_region(MKDEV(disk->major, disk->first_minor),
			    disk->minors, NULL, exact_match, exact_lock, disk);
}

EXPORT_SYMBOL_GPL(ide_register_region);

void ide_unregister_region(struct gendisk *disk)
{
	blk_unregister_region(MKDEV(disk->major, disk->first_minor),
			      disk->minors);
}

EXPORT_SYMBOL_GPL(ide_unregister_region);

void ide_init_disk(struct gendisk *disk, ide_drive_t *drive)
{
	ide_hwif_t *hwif = drive->hwif;
	unsigned int unit = (drive->select.all >> 4) & 1;

	disk->major = hwif->major;
	disk->first_minor = unit << PARTN_BITS;
	sprintf(disk->disk_name, "hd%c", 'a' + hwif->index * MAX_DRIVES + unit);
	disk->queue = drive->queue;
}

EXPORT_SYMBOL_GPL(ide_init_disk);

static void ide_remove_drive_from_hwgroup(ide_drive_t *drive)
{
	ide_hwgroup_t *hwgroup = drive->hwif->hwgroup;

	if (drive == drive->next) {
		/* special case: last drive from hwgroup. */
		BUG_ON(hwgroup->drive != drive);
		hwgroup->drive = NULL;
	} else {
		ide_drive_t *walk;

		walk = hwgroup->drive;
		while (walk->next != drive)
			walk = walk->next;
		walk->next = drive->next;
		if (hwgroup->drive == drive) {
			hwgroup->drive = drive->next;
			hwgroup->hwif = hwgroup->drive->hwif;
		}
	}
	BUG_ON(hwgroup->drive == drive);
}

static void drive_release_dev (struct device *dev)
{
	ide_drive_t *drive = container_of(dev, ide_drive_t, gendev);

	spin_lock_irq(&ide_lock);
	if (drive->devfs_name[0] != '\0') {
		devfs_remove(drive->devfs_name);
		drive->devfs_name[0] = '\0';
	}
	ide_remove_drive_from_hwgroup(drive);
	if (drive->id != NULL) {
		kfree(drive->id);
		drive->id = NULL;
	}
	drive->present = 0;
	/* Messed up locking ... */
	spin_unlock_irq(&ide_lock);
	blk_cleanup_queue(drive->queue);
	spin_lock_irq(&ide_lock);
	drive->queue = NULL;
	spin_unlock_irq(&ide_lock);

	up(&drive->gendev_rel_sem);
}

/*
 * init_gendisk() (as opposed to ide_geninit) is called for each major device,
 * after probing for drives, to allocate partition tables and other data
 * structures needed for the routines in genhd.c.  ide_geninit() gets called
 * somewhat later, during the partition check.
 */
static void init_gendisk (ide_hwif_t *hwif)
{
	unsigned int unit;

	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t * drive = &hwif->drives[unit];
		ide_add_generic_settings(drive);
		snprintf(drive->gendev.bus_id,BUS_ID_SIZE,"%u.%u",
			 hwif->index,unit);
		drive->gendev.parent = &hwif->gendev;
		drive->gendev.bus = &ide_bus_type;
		drive->gendev.driver_data = drive;
		drive->gendev.release = drive_release_dev;
		if (drive->present) {
			sprintf(drive->devfs_name, "ide/host%d/bus%d/target%d/lun%d",
				(hwif->channel && hwif->mate) ?
				hwif->mate->index : hwif->index,
				hwif->channel, unit, drive->lun);
		}
	}
	blk_register_region(MKDEV(hwif->major, 0), MAX_DRIVES << PARTN_BITS,
			THIS_MODULE, ata_probe, ata_lock, hwif);
}

static int hwif_init(ide_hwif_t *hwif)
{
	int old_irq;

	/* Return success if no device is connected */
	if (!hwif->present)
		return 1;

	if (!hwif->irq) {
		if (!(hwif->irq = ide_default_irq(hwif->io_ports[IDE_DATA_OFFSET])))
		{
			printk("%s: DISABLED, NO IRQ\n", hwif->name);
			return (hwif->present = 0);
		}
	}
#ifdef CONFIG_BLK_DEV_HD
	if (hwif->irq == HD_IRQ && hwif->io_ports[IDE_DATA_OFFSET] != HD_DATA) {
		printk("%s: CANNOT SHARE IRQ WITH OLD "
			"HARDDISK DRIVER (hd.c)\n", hwif->name);
		return (hwif->present = 0);
	}
#endif /* CONFIG_BLK_DEV_HD */

	/* we set it back to 1 if all is ok below */	
	hwif->present = 0;

	if (register_blkdev(hwif->major, hwif->name))
		return 0;

	if (!hwif->sg_max_nents)
		hwif->sg_max_nents = PRD_ENTRIES;

	hwif->sg_table = kmalloc(sizeof(struct scatterlist)*hwif->sg_max_nents,
				 GFP_KERNEL);
	if (!hwif->sg_table) {
		printk(KERN_ERR "%s: unable to allocate SG table.\n", hwif->name);
		goto out;
	}
	
	if (init_irq(hwif) == 0)
		goto done;

	old_irq = hwif->irq;
	/*
	 *	It failed to initialise. Find the default IRQ for 
	 *	this port and try that.
	 */
	if (!(hwif->irq = ide_default_irq(hwif->io_ports[IDE_DATA_OFFSET]))) {
		printk("%s: Disabled unable to get IRQ %d.\n",
			hwif->name, old_irq);
		goto out;
	}
	if (init_irq(hwif)) {
		printk("%s: probed IRQ %d and default IRQ %d failed.\n",
			hwif->name, old_irq, hwif->irq);
		goto out;
	}
	printk("%s: probed IRQ %d failed, using default.\n",
		hwif->name, hwif->irq);

done:
	init_gendisk(hwif);
	hwif->present = 1;	/* success */
	return 1;

out:
	unregister_blkdev(hwif->major, hwif->name);
	return 0;
}

int ideprobe_init (void)
{
	unsigned int index;
	int probe[MAX_HWIFS];

	memset(probe, 0, MAX_HWIFS * sizeof(int));
	for (index = 0; index < MAX_HWIFS; ++index)
		probe[index] = !ide_hwifs[index].present;

	for (index = 0; index < MAX_HWIFS; ++index)
		if (probe[index])
			probe_hwif(&ide_hwifs[index]);
	for (index = 0; index < MAX_HWIFS; ++index)
		if (probe[index])
			hwif_init(&ide_hwifs[index]);
	for (index = 0; index < MAX_HWIFS; ++index) {
		if (probe[index]) {
			ide_hwif_t *hwif = &ide_hwifs[index];
			int unit;
			if (!hwif->present)
				continue;
			if (hwif->chipset == ide_unknown || hwif->chipset == ide_forced)
				hwif->chipset = ide_generic;
			for (unit = 0; unit < MAX_DRIVES; ++unit)
				if (hwif->drives[unit].present)
					device_register(&hwif->drives[unit].gendev);
		}
	}
	return 0;
}

EXPORT_SYMBOL_GPL(ideprobe_init);