aboutsummaryrefslogtreecommitdiff
path: root/drivers/ata/libata-acpi.c
blob: 446b4e761af04658abde838561fe11715601f561 (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
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
/*
 * libata-acpi.c
 * Provides ACPI support for PATA/SATA.
 *
 * Copyright (C) 2006 Intel Corp.
 * Copyright (C) 2006 Randy Dunlap
 */

#include <linux/module.h>
#include <linux/ata.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/acpi.h>
#include <linux/libata.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <scsi/scsi_device.h>
#include "libata.h"

#include <acpi/acpi_bus.h>

unsigned int ata_acpi_gtf_filter = ATA_ACPI_FILTER_DEFAULT;
module_param_named(acpi_gtf_filter, ata_acpi_gtf_filter, int, 0644);
MODULE_PARM_DESC(acpi_gtf_filter, "filter mask for ACPI _GTF commands, set to filter out (0x1=set xfermode, 0x2=lock/freeze lock, 0x4=DIPM, 0x8=FPDMA non-zero offset, 0x10=FPDMA DMA Setup FIS auto-activate)");

#define NO_PORT_MULT		0xffff
#define SATA_ADR(root, pmp)	(((root) << 16) | (pmp))

#define REGS_PER_GTF		7
struct ata_acpi_gtf {
	u8	tf[REGS_PER_GTF];	/* regs. 0x1f1 - 0x1f7 */
} __packed;

/*
 *	Helper - belongs in the PCI layer somewhere eventually
 */
static int is_pci_dev(struct device *dev)
{
	return (dev->bus == &pci_bus_type);
}

static void ata_acpi_clear_gtf(struct ata_device *dev)
{
	kfree(dev->gtf_cache);
	dev->gtf_cache = NULL;
}

/**
 * ata_ap_acpi_handle - provide the acpi_handle for an ata_port
 * @ap: the acpi_handle returned will correspond to this port
 *
 * Returns the acpi_handle for the ACPI namespace object corresponding to
 * the ata_port passed into the function, or NULL if no such object exists
 */
acpi_handle ata_ap_acpi_handle(struct ata_port *ap)
{
	if (ap->flags & ATA_FLAG_ACPI_SATA)
		return NULL;

	return acpi_get_child(DEVICE_ACPI_HANDLE(ap->host->dev), ap->port_no);
}
EXPORT_SYMBOL(ata_ap_acpi_handle);

/**
 * ata_dev_acpi_handle - provide the acpi_handle for an ata_device
 * @dev: the acpi_device returned will correspond to this port
 *
 * Returns the acpi_handle for the ACPI namespace object corresponding to
 * the ata_device passed into the function, or NULL if no such object exists
 */
acpi_handle ata_dev_acpi_handle(struct ata_device *dev)
{
	acpi_integer adr;
	struct ata_port *ap = dev->link->ap;

	if (dev->flags & ATA_DFLAG_ACPI_DISABLED)
		return NULL;

	if (ap->flags & ATA_FLAG_ACPI_SATA) {
		if (!sata_pmp_attached(ap))
			adr = SATA_ADR(ap->port_no, NO_PORT_MULT);
		else
			adr = SATA_ADR(ap->port_no, dev->link->pmp);
		return acpi_get_child(DEVICE_ACPI_HANDLE(ap->host->dev), adr);
	} else
		return acpi_get_child(ata_ap_acpi_handle(ap), dev->devno);
}
EXPORT_SYMBOL(ata_dev_acpi_handle);

/* @ap and @dev are the same as ata_acpi_handle_hotplug() */
static void ata_acpi_detach_device(struct ata_port *ap, struct ata_device *dev)
{
	if (dev)
		dev->flags |= ATA_DFLAG_DETACH;
	else {
		struct ata_link *tlink;
		struct ata_device *tdev;

		ata_for_each_link(tlink, ap, EDGE)
			ata_for_each_dev(tdev, tlink, ALL)
				tdev->flags |= ATA_DFLAG_DETACH;
	}

	ata_port_schedule_eh(ap);
}

/**
 * ata_acpi_handle_hotplug - ACPI event handler backend
 * @ap: ATA port ACPI event occurred
 * @dev: ATA device ACPI event occurred (can be NULL)
 * @event: ACPI event which occurred
 *
 * All ACPI bay / device realted events end up in this function.  If
 * the event is port-wide @dev is NULL.  If the event is specific to a
 * device, @dev points to it.
 *
 * Hotplug (as opposed to unplug) notification is always handled as
 * port-wide while unplug only kills the target device on device-wide
 * event.
 *
 * LOCKING:
 * ACPI notify handler context.  May sleep.
 */
static void ata_acpi_handle_hotplug(struct ata_port *ap, struct ata_device *dev,
				    u32 event)
{
	struct ata_eh_info *ehi = &ap->link.eh_info;
	int wait = 0;
	unsigned long flags;

	spin_lock_irqsave(ap->lock, flags);
	/*
	 * When dock driver calls into the routine, it will always use
	 * ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
	 * ACPI_NOTIFY_EJECT_REQUEST for remove
	 */
	switch (event) {
	case ACPI_NOTIFY_BUS_CHECK:
	case ACPI_NOTIFY_DEVICE_CHECK:
		ata_ehi_push_desc(ehi, "ACPI event");

		ata_ehi_hotplugged(ehi);
		ata_port_freeze(ap);
		break;
	case ACPI_NOTIFY_EJECT_REQUEST:
		ata_ehi_push_desc(ehi, "ACPI event");

		ata_acpi_detach_device(ap, dev);
		wait = 1;
		break;
	}

	spin_unlock_irqrestore(ap->lock, flags);

	if (wait)
		ata_port_wait_eh(ap);
}

static void ata_acpi_dev_notify_dock(acpi_handle handle, u32 event, void *data)
{
	struct ata_device *dev = data;

	ata_acpi_handle_hotplug(dev->link->ap, dev, event);
}

static void ata_acpi_ap_notify_dock(acpi_handle handle, u32 event, void *data)
{
	struct ata_port *ap = data;

	ata_acpi_handle_hotplug(ap, NULL, event);
}

static void ata_acpi_uevent(struct ata_port *ap, struct ata_device *dev,
	u32 event)
{
	struct kobject *kobj = NULL;
	char event_string[20];
	char *envp[] = { event_string, NULL };

	if (dev) {
		if (dev->sdev)
			kobj = &dev->sdev->sdev_gendev.kobj;
	} else
		kobj = &ap->dev->kobj;

	if (kobj) {
		snprintf(event_string, 20, "BAY_EVENT=%d", event);
		kobject_uevent_env(kobj, KOBJ_CHANGE, envp);
	}
}

static void ata_acpi_ap_uevent(acpi_handle handle, u32 event, void *data)
{
	ata_acpi_uevent(data, NULL, event);
}

static void ata_acpi_dev_uevent(acpi_handle handle, u32 event, void *data)
{
	struct ata_device *dev = data;
	ata_acpi_uevent(dev->link->ap, dev, event);
}

static const struct acpi_dock_ops ata_acpi_dev_dock_ops = {
	.handler = ata_acpi_dev_notify_dock,
	.uevent = ata_acpi_dev_uevent,
};

static const struct acpi_dock_ops ata_acpi_ap_dock_ops = {
	.handler = ata_acpi_ap_notify_dock,
	.uevent = ata_acpi_ap_uevent,
};

/**
 * ata_acpi_dissociate - dissociate ATA host from ACPI objects
 * @host: target ATA host
 *
 * This function is called during driver detach after the whole host
 * is shut down.
 *
 * LOCKING:
 * EH context.
 */
void ata_acpi_dissociate(struct ata_host *host)
{
	int i;

	/* Restore initial _GTM values so that driver which attaches
	 * afterward can use them too.
	 */
	for (i = 0; i < host->n_ports; i++) {
		struct ata_port *ap = host->ports[i];
		const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);

		if (ata_ap_acpi_handle(ap) && gtm)
			ata_acpi_stm(ap, gtm);
	}
}

/**
 * ata_acpi_gtm - execute _GTM
 * @ap: target ATA port
 * @gtm: out parameter for _GTM result
 *
 * Evaluate _GTM and store the result in @gtm.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * 0 on success, -ENOENT if _GTM doesn't exist, -errno on failure.
 */
int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *gtm)
{
	struct acpi_buffer output = { .length = ACPI_ALLOCATE_BUFFER };
	union acpi_object *out_obj;
	acpi_status status;
	int rc = 0;

	status = acpi_evaluate_object(ata_ap_acpi_handle(ap), "_GTM", NULL,
				      &output);

	rc = -ENOENT;
	if (status == AE_NOT_FOUND)
		goto out_free;

	rc = -EINVAL;
	if (ACPI_FAILURE(status)) {
		ata_port_err(ap, "ACPI get timing mode failed (AE 0x%x)\n",
			     status);
		goto out_free;
	}

	out_obj = output.pointer;
	if (out_obj->type != ACPI_TYPE_BUFFER) {
		ata_port_warn(ap, "_GTM returned unexpected object type 0x%x\n",
			      out_obj->type);

		goto out_free;
	}

	if (out_obj->buffer.length != sizeof(struct ata_acpi_gtm)) {
		ata_port_err(ap, "_GTM returned invalid length %d\n",
			     out_obj->buffer.length);
		goto out_free;
	}

	memcpy(gtm, out_obj->buffer.pointer, sizeof(struct ata_acpi_gtm));
	rc = 0;
 out_free:
	kfree(output.pointer);
	return rc;
}

EXPORT_SYMBOL_GPL(ata_acpi_gtm);

/**
 * ata_acpi_stm - execute _STM
 * @ap: target ATA port
 * @stm: timing parameter to _STM
 *
 * Evaluate _STM with timing parameter @stm.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * 0 on success, -ENOENT if _STM doesn't exist, -errno on failure.
 */
int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm)
{
	acpi_status status;
	struct ata_acpi_gtm		stm_buf = *stm;
	struct acpi_object_list         input;
	union acpi_object               in_params[3];

	in_params[0].type = ACPI_TYPE_BUFFER;
	in_params[0].buffer.length = sizeof(struct ata_acpi_gtm);
	in_params[0].buffer.pointer = (u8 *)&stm_buf;
	/* Buffers for id may need byteswapping ? */
	in_params[1].type = ACPI_TYPE_BUFFER;
	in_params[1].buffer.length = 512;
	in_params[1].buffer.pointer = (u8 *)ap->link.device[0].id;
	in_params[2].type = ACPI_TYPE_BUFFER;
	in_params[2].buffer.length = 512;
	in_params[2].buffer.pointer = (u8 *)ap->link.device[1].id;

	input.count = 3;
	input.pointer = in_params;

	status = acpi_evaluate_object(ata_ap_acpi_handle(ap), "_STM", &input,
				      NULL);

	if (status == AE_NOT_FOUND)
		return -ENOENT;
	if (ACPI_FAILURE(status)) {
		ata_port_err(ap, "ACPI set timing mode failed (status=0x%x)\n",
			     status);
		return -EINVAL;
	}
	return 0;
}

EXPORT_SYMBOL_GPL(ata_acpi_stm);

/**
 * ata_dev_get_GTF - get the drive bootup default taskfile settings
 * @dev: target ATA device
 * @gtf: output parameter for buffer containing _GTF taskfile arrays
 *
 * This applies to both PATA and SATA drives.
 *
 * The _GTF method has no input parameters.
 * It returns a variable number of register set values (registers
 * hex 1F1..1F7, taskfiles).
 * The <variable number> is not known in advance, so have ACPI-CA
 * allocate the buffer as needed and return it, then free it later.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * Number of taskfiles on success, 0 if _GTF doesn't exist.  -EINVAL
 * if _GTF is invalid.
 */
static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf)
{
	struct ata_port *ap = dev->link->ap;
	acpi_status status;
	struct acpi_buffer output;
	union acpi_object *out_obj;
	int rc = 0;

	/* if _GTF is cached, use the cached value */
	if (dev->gtf_cache) {
		out_obj = dev->gtf_cache;
		goto done;
	}

	/* set up output buffer */
	output.length = ACPI_ALLOCATE_BUFFER;
	output.pointer = NULL;	/* ACPI-CA sets this; save/free it later */

	if (ata_msg_probe(ap))
		ata_dev_dbg(dev, "%s: ENTER: port#: %d\n",
			    __func__, ap->port_no);

	/* _GTF has no input parameters */
	status = acpi_evaluate_object(ata_dev_acpi_handle(dev), "_GTF", NULL,
				      &output);
	out_obj = dev->gtf_cache = output.pointer;

	if (ACPI_FAILURE(status)) {
		if (status != AE_NOT_FOUND) {
			ata_dev_warn(dev, "_GTF evaluation failed (AE 0x%x)\n",
				     status);
			rc = -EINVAL;
		}
		goto out_free;
	}

	if (!output.length || !output.pointer) {
		if (ata_msg_probe(ap))
			ata_dev_dbg(dev, "%s: Run _GTF: length or ptr is NULL (0x%llx, 0x%p)\n",
				    __func__,
				    (unsigned long long)output.length,
				    output.pointer);
		rc = -EINVAL;
		goto out_free;
	}

	if (out_obj->type != ACPI_TYPE_BUFFER) {
		ata_dev_warn(dev, "_GTF unexpected object type 0x%x\n",
			     out_obj->type);
		rc = -EINVAL;
		goto out_free;
	}

	if (out_obj->buffer.length % REGS_PER_GTF) {
		ata_dev_warn(dev, "unexpected _GTF length (%d)\n",
			     out_obj->buffer.length);
		rc = -EINVAL;
		goto out_free;
	}

 done:
	rc = out_obj->buffer.length / REGS_PER_GTF;
	if (gtf) {
		*gtf = (void *)out_obj->buffer.pointer;
		if (ata_msg_probe(ap))
			ata_dev_dbg(dev, "%s: returning gtf=%p, gtf_count=%d\n",
				    __func__, *gtf, rc);
	}
	return rc;

 out_free:
	ata_acpi_clear_gtf(dev);
	return rc;
}

/**
 * ata_acpi_gtm_xfermode - determine xfermode from GTM parameter
 * @dev: target device
 * @gtm: GTM parameter to use
 *
 * Determine xfermask for @dev from @gtm.
 *
 * LOCKING:
 * None.
 *
 * RETURNS:
 * Determined xfermask.
 */
unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
				    const struct ata_acpi_gtm *gtm)
{
	unsigned long xfer_mask = 0;
	unsigned int type;
	int unit;
	u8 mode;

	/* we always use the 0 slot for crap hardware */
	unit = dev->devno;
	if (!(gtm->flags & 0x10))
		unit = 0;

	/* PIO */
	mode = ata_timing_cycle2mode(ATA_SHIFT_PIO, gtm->drive[unit].pio);
	xfer_mask |= ata_xfer_mode2mask(mode);

	/* See if we have MWDMA or UDMA data. We don't bother with
	 * MWDMA if UDMA is available as this means the BIOS set UDMA
	 * and our error changedown if it works is UDMA to PIO anyway.
	 */
	if (!(gtm->flags & (1 << (2 * unit))))
		type = ATA_SHIFT_MWDMA;
	else
		type = ATA_SHIFT_UDMA;

	mode = ata_timing_cycle2mode(type, gtm->drive[unit].dma);
	xfer_mask |= ata_xfer_mode2mask(mode);

	return xfer_mask;
}
EXPORT_SYMBOL_GPL(ata_acpi_gtm_xfermask);

/**
 * ata_acpi_cbl_80wire		-	Check for 80 wire cable
 * @ap: Port to check
 * @gtm: GTM data to use
 *
 * Return 1 if the @gtm indicates the BIOS selected an 80wire mode.
 */
int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm)
{
	struct ata_device *dev;

	ata_for_each_dev(dev, &ap->link, ENABLED) {
		unsigned long xfer_mask, udma_mask;

		xfer_mask = ata_acpi_gtm_xfermask(dev, gtm);
		ata_unpack_xfermask(xfer_mask, NULL, NULL, &udma_mask);

		if (udma_mask & ~ATA_UDMA_MASK_40C)
			return 1;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(ata_acpi_cbl_80wire);

static void ata_acpi_gtf_to_tf(struct ata_device *dev,
			       const struct ata_acpi_gtf *gtf,
			       struct ata_taskfile *tf)
{
	ata_tf_init(dev, tf);

	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
	tf->protocol = ATA_PROT_NODATA;
	tf->feature = gtf->tf[0];	/* 0x1f1 */
	tf->nsect   = gtf->tf[1];	/* 0x1f2 */
	tf->lbal    = gtf->tf[2];	/* 0x1f3 */
	tf->lbam    = gtf->tf[3];	/* 0x1f4 */
	tf->lbah    = gtf->tf[4];	/* 0x1f5 */
	tf->device  = gtf->tf[5];	/* 0x1f6 */
	tf->command = gtf->tf[6];	/* 0x1f7 */
}

static int ata_acpi_filter_tf(struct ata_device *dev,
			      const struct ata_taskfile *tf,
			      const struct ata_taskfile *ptf)
{
	if (dev->gtf_filter & ATA_ACPI_FILTER_SETXFER) {
		/* libata doesn't use ACPI to configure transfer mode.
		 * It will only confuse device configuration.  Skip.
		 */
		if (tf->command == ATA_CMD_SET_FEATURES &&
		    tf->feature == SETFEATURES_XFER)
			return 1;
	}

	if (dev->gtf_filter & ATA_ACPI_FILTER_LOCK) {
		/* BIOS writers, sorry but we don't wanna lock
		 * features unless the user explicitly said so.
		 */

		/* DEVICE CONFIGURATION FREEZE LOCK */
		if (tf->command == ATA_CMD_CONF_OVERLAY &&
		    tf->feature == ATA_DCO_FREEZE_LOCK)
			return 1;

		/* SECURITY FREEZE LOCK */
		if (tf->command == ATA_CMD_SEC_FREEZE_LOCK)
			return 1;

		/* SET MAX LOCK and SET MAX FREEZE LOCK */
		if ((!ptf || ptf->command != ATA_CMD_READ_NATIVE_MAX) &&
		    tf->command == ATA_CMD_SET_MAX &&
		    (tf->feature == ATA_SET_MAX_LOCK ||
		     tf->feature == ATA_SET_MAX_FREEZE_LOCK))
			return 1;
	}

	if (tf->command == ATA_CMD_SET_FEATURES &&
	    tf->feature == SETFEATURES_SATA_ENABLE) {
		/* inhibit enabling DIPM */
		if (dev->gtf_filter & ATA_ACPI_FILTER_DIPM &&
		    tf->nsect == SATA_DIPM)
			return 1;

		/* inhibit FPDMA non-zero offset */
		if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_OFFSET &&
		    (tf->nsect == SATA_FPDMA_OFFSET ||
		     tf->nsect == SATA_FPDMA_IN_ORDER))
			return 1;

		/* inhibit FPDMA auto activation */
		if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_AA &&
		    tf->nsect == SATA_FPDMA_AA)
			return 1;
	}

	return 0;
}

/**
 * ata_acpi_run_tf - send taskfile registers to host controller
 * @dev: target ATA device
 * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
 *
 * Outputs ATA taskfile to standard ATA host controller.
 * Writes the control, feature, nsect, lbal, lbam, and lbah registers.
 * Optionally (ATA_TFLAG_LBA48) writes hob_feature, hob_nsect,
 * hob_lbal, hob_lbam, and hob_lbah.
 *
 * This function waits for idle (!BUSY and !DRQ) after writing
 * registers.  If the control register has a new value, this
 * function also waits for idle after writing control and before
 * writing the remaining registers.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * 1 if command is executed successfully.  0 if ignored, rejected or
 * filtered out, -errno on other errors.
 */
static int ata_acpi_run_tf(struct ata_device *dev,
			   const struct ata_acpi_gtf *gtf,
			   const struct ata_acpi_gtf *prev_gtf)
{
	struct ata_taskfile *pptf = NULL;
	struct ata_taskfile tf, ptf, rtf;
	unsigned int err_mask;
	const char *level;
	const char *descr;
	char msg[60];
	int rc;

	if ((gtf->tf[0] == 0) && (gtf->tf[1] == 0) && (gtf->tf[2] == 0)
	    && (gtf->tf[3] == 0) && (gtf->tf[4] == 0) && (gtf->tf[5] == 0)
	    && (gtf->tf[6] == 0))
		return 0;

	ata_acpi_gtf_to_tf(dev, gtf, &tf);
	if (prev_gtf) {
		ata_acpi_gtf_to_tf(dev, prev_gtf, &ptf);
		pptf = &ptf;
	}

	if (!ata_acpi_filter_tf(dev, &tf, pptf)) {
		rtf = tf;
		err_mask = ata_exec_internal(dev, &rtf, NULL,
					     DMA_NONE, NULL, 0, 0);

		switch (err_mask) {
		case 0:
			level = KERN_DEBUG;
			snprintf(msg, sizeof(msg), "succeeded");
			rc = 1;
			break;

		case AC_ERR_DEV:
			level = KERN_INFO;
			snprintf(msg, sizeof(msg),
				 "rejected by device (Stat=0x%02x Err=0x%02x)",
				 rtf.command, rtf.feature);
			rc = 0;
			break;

		default:
			level = KERN_ERR;
			snprintf(msg, sizeof(msg),
				 "failed (Emask=0x%x Stat=0x%02x Err=0x%02x)",
				 err_mask, rtf.command, rtf.feature);
			rc = -EIO;
			break;
		}
	} else {
		level = KERN_INFO;
		snprintf(msg, sizeof(msg), "filtered out");
		rc = 0;
	}
	descr = ata_get_cmd_descript(tf.command);

	ata_dev_printk(dev, level,
		       "ACPI cmd %02x/%02x:%02x:%02x:%02x:%02x:%02x (%s) %s\n",
		       tf.command, tf.feature, tf.nsect, tf.lbal,
		       tf.lbam, tf.lbah, tf.device,
		       (descr ? descr : "unknown"), msg);

	return rc;
}

/**
 * ata_acpi_exec_tfs - get then write drive taskfile settings
 * @dev: target ATA device
 * @nr_executed: out parameter for the number of executed commands
 *
 * Evaluate _GTF and execute returned taskfiles.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * Number of executed taskfiles on success, 0 if _GTF doesn't exist.
 * -errno on other errors.
 */
static int ata_acpi_exec_tfs(struct ata_device *dev, int *nr_executed)
{
	struct ata_acpi_gtf *gtf = NULL, *pgtf = NULL;
	int gtf_count, i, rc;

	/* get taskfiles */
	rc = ata_dev_get_GTF(dev, &gtf);
	if (rc < 0)
		return rc;
	gtf_count = rc;

	/* execute them */
	for (i = 0; i < gtf_count; i++, gtf++) {
		rc = ata_acpi_run_tf(dev, gtf, pgtf);
		if (rc < 0)
			break;
		if (rc) {
			(*nr_executed)++;
			pgtf = gtf;
		}
	}

	ata_acpi_clear_gtf(dev);

	if (rc < 0)
		return rc;
	return 0;
}

/**
 * ata_acpi_push_id - send Identify data to drive
 * @dev: target ATA device
 *
 * _SDD ACPI object: for SATA mode only
 * Must be after Identify (Packet) Device -- uses its data
 * ATM this function never returns a failure.  It is an optional
 * method and if it fails for whatever reason, we should still
 * just keep going.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * 0 on success, -ENOENT if _SDD doesn't exist, -errno on failure.
 */
static int ata_acpi_push_id(struct ata_device *dev)
{
	struct ata_port *ap = dev->link->ap;
	acpi_status status;
	struct acpi_object_list input;
	union acpi_object in_params[1];

	if (ata_msg_probe(ap))
		ata_dev_dbg(dev, "%s: ix = %d, port#: %d\n",
			    __func__, dev->devno, ap->port_no);

	/* Give the drive Identify data to the drive via the _SDD method */
	/* _SDD: set up input parameters */
	input.count = 1;
	input.pointer = in_params;
	in_params[0].type = ACPI_TYPE_BUFFER;
	in_params[0].buffer.length = sizeof(dev->id[0]) * ATA_ID_WORDS;
	in_params[0].buffer.pointer = (u8 *)dev->id;
	/* Output buffer: _SDD has no output */

	/* It's OK for _SDD to be missing too. */
	swap_buf_le16(dev->id, ATA_ID_WORDS);
	status = acpi_evaluate_object(ata_dev_acpi_handle(dev), "_SDD", &input,
				      NULL);
	swap_buf_le16(dev->id, ATA_ID_WORDS);

	if (status == AE_NOT_FOUND)
		return -ENOENT;

	if (ACPI_FAILURE(status)) {
		ata_dev_warn(dev, "ACPI _SDD failed (AE 0x%x)\n", status);
		return -EIO;
	}

	return 0;
}

/**
 * ata_acpi_on_suspend - ATA ACPI hook called on suspend
 * @ap: target ATA port
 *
 * This function is called when @ap is about to be suspended.  All
 * devices are already put to sleep but the port_suspend() callback
 * hasn't been executed yet.  Error return from this function aborts
 * suspend.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * 0 on success, -errno on failure.
 */
int ata_acpi_on_suspend(struct ata_port *ap)
{
	/* nada */
	return 0;
}

/**
 * ata_acpi_on_resume - ATA ACPI hook called on resume
 * @ap: target ATA port
 *
 * This function is called when @ap is resumed - right after port
 * itself is resumed but before any EH action is taken.
 *
 * LOCKING:
 * EH context.
 */
void ata_acpi_on_resume(struct ata_port *ap)
{
	const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
	struct ata_device *dev;

	if (ata_ap_acpi_handle(ap) && gtm) {
		/* _GTM valid */

		/* restore timing parameters */
		ata_acpi_stm(ap, gtm);

		/* _GTF should immediately follow _STM so that it can
		 * use values set by _STM.  Cache _GTF result and
		 * schedule _GTF.
		 */
		ata_for_each_dev(dev, &ap->link, ALL) {
			ata_acpi_clear_gtf(dev);
			if (ata_dev_enabled(dev) &&
			    ata_dev_get_GTF(dev, NULL) >= 0)
				dev->flags |= ATA_DFLAG_ACPI_PENDING;
		}
	} else {
		/* SATA _GTF needs to be evaulated after _SDD and
		 * there's no reason to evaluate IDE _GTF early
		 * without _STM.  Clear cache and schedule _GTF.
		 */
		ata_for_each_dev(dev, &ap->link, ALL) {
			ata_acpi_clear_gtf(dev);
			if (ata_dev_enabled(dev))
				dev->flags |= ATA_DFLAG_ACPI_PENDING;
		}
	}
}

/**
 * ata_acpi_set_state - set the port power state
 * @ap: target ATA port
 * @state: state, on/off
 *
 * This function executes the _PS0/_PS3 ACPI method to set the power state.
 * ACPI spec requires _PS0 when IDE power on and _PS3 when power off
 */
void ata_acpi_set_state(struct ata_port *ap, pm_message_t state)
{
	struct ata_device *dev;
	acpi_handle handle;
	int acpi_state;

	/* channel first and then drives for power on and vica versa
	   for power off */
	handle = ata_ap_acpi_handle(ap);
	if (handle && state.event == PM_EVENT_ON)
		acpi_bus_set_power(handle, ACPI_STATE_D0);

	ata_for_each_dev(dev, &ap->link, ENABLED) {
		handle = ata_dev_acpi_handle(dev);
		if (!handle)
			continue;

		if (state.event != PM_EVENT_ON) {
			acpi_state = acpi_pm_device_sleep_state(
				&dev->sdev->sdev_gendev, NULL, ACPI_STATE_D3);
			if (acpi_state > 0)
				acpi_bus_set_power(handle, acpi_state);
			/* TBD: need to check if it's runtime pm request */
			acpi_pm_device_run_wake(
				&dev->sdev->sdev_gendev, true);
		} else {
			/* Ditto */
			acpi_pm_device_run_wake(
				&dev->sdev->sdev_gendev, false);
			acpi_bus_set_power(handle, ACPI_STATE_D0);
		}
	}

	handle = ata_ap_acpi_handle(ap);
	if (handle && state.event != PM_EVENT_ON)
		acpi_bus_set_power(handle, ACPI_STATE_D3);
}

/**
 * ata_acpi_on_devcfg - ATA ACPI hook called on device donfiguration
 * @dev: target ATA device
 *
 * This function is called when @dev is about to be configured.
 * IDENTIFY data might have been modified after this hook is run.
 *
 * LOCKING:
 * EH context.
 *
 * RETURNS:
 * Positive number if IDENTIFY data needs to be refreshed, 0 if not,
 * -errno on failure.
 */
int ata_acpi_on_devcfg(struct ata_device *dev)
{
	struct ata_port *ap = dev->link->ap;
	struct ata_eh_context *ehc = &ap->link.eh_context;
	int acpi_sata = ap->flags & ATA_FLAG_ACPI_SATA;
	int nr_executed = 0;
	int rc;

	if (!ata_dev_acpi_handle(dev))
		return 0;

	/* do we need to do _GTF? */
	if (!(dev->flags & ATA_DFLAG_ACPI_PENDING) &&
	    !(acpi_sata && (ehc->i.flags & ATA_EHI_DID_HARDRESET)))
		return 0;

	/* do _SDD if SATA */
	if (acpi_sata) {
		rc = ata_acpi_push_id(dev);
		if (rc && rc != -ENOENT)
			goto acpi_err;
	}

	/* do _GTF */
	rc = ata_acpi_exec_tfs(dev, &nr_executed);
	if (rc)
		goto acpi_err;

	dev->flags &= ~ATA_DFLAG_ACPI_PENDING;

	/* refresh IDENTIFY page if any _GTF command has been executed */
	if (nr_executed) {
		rc = ata_dev_reread_id(dev, 0);
		if (rc < 0) {
			ata_dev_err(dev,
				    "failed to IDENTIFY after ACPI commands\n");
			return rc;
		}
	}

	return 0;

 acpi_err:
	/* ignore evaluation failure if we can continue safely */
	if (rc == -EINVAL && !nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
		return 0;

	/* fail and let EH retry once more for unknown IO errors */
	if (!(dev->flags & ATA_DFLAG_ACPI_FAILED)) {
		dev->flags |= ATA_DFLAG_ACPI_FAILED;
		return rc;
	}

	dev->flags |= ATA_DFLAG_ACPI_DISABLED;
	ata_dev_warn(dev, "ACPI: failed the second time, disabled\n");

	/* We can safely continue if no _GTF command has been executed
	 * and port is not frozen.
	 */
	if (!nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
		return 0;

	return rc;
}

/**
 * ata_acpi_on_disable - ATA ACPI hook called when a device is disabled
 * @dev: target ATA device
 *
 * This function is called when @dev is about to be disabled.
 *
 * LOCKING:
 * EH context.
 */
void ata_acpi_on_disable(struct ata_device *dev)
{
	ata_acpi_clear_gtf(dev);
}

static void ata_acpi_register_power_resource(struct ata_device *dev)
{
	struct scsi_device *sdev = dev->sdev;
	acpi_handle handle;
	struct device *device;

	handle = ata_dev_acpi_handle(dev);
	if (!handle)
		return;

	device = &sdev->sdev_gendev;

	acpi_power_resource_register_device(device, handle);
}

static void ata_acpi_unregister_power_resource(struct ata_device *dev)
{
	struct scsi_device *sdev = dev->sdev;
	acpi_handle handle;
	struct device *device;

	handle = ata_dev_acpi_handle(dev);
	if (!handle)
		return;

	device = &sdev->sdev_gendev;

	acpi_power_resource_unregister_device(device, handle);
}

void ata_acpi_bind(struct ata_device *dev)
{
	ata_acpi_register_power_resource(dev);
}

void ata_acpi_unbind(struct ata_device *dev)
{
	ata_acpi_unregister_power_resource(dev);
}

static int compat_pci_ata(struct ata_port *ap)
{
	struct device *dev = ap->tdev.parent;
	struct pci_dev *pdev;

	if (!is_pci_dev(dev))
		return 0;

	pdev = to_pci_dev(dev);

	if ((pdev->class >> 8) != PCI_CLASS_STORAGE_SATA &&
	    (pdev->class >> 8) != PCI_CLASS_STORAGE_IDE)
		return 0;

	return 1;
}

static int ata_acpi_bind_host(struct ata_port *ap, acpi_handle *handle)
{
	if (ap->flags & ATA_FLAG_ACPI_SATA)
		return -ENODEV;

	*handle = acpi_get_child(DEVICE_ACPI_HANDLE(ap->tdev.parent),
			ap->port_no);

	if (!*handle)
		return -ENODEV;

	if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
		ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;

	return 0;
}

static int ata_acpi_bind_device(struct ata_port *ap, struct scsi_device *sdev,
				acpi_handle *handle)
{
	struct ata_device *ata_dev;

	if (ap->flags & ATA_FLAG_ACPI_SATA) {
		if (!sata_pmp_attached(ap))
			ata_dev = &ap->link.device[sdev->id];
		else
			ata_dev = &ap->pmp_link[sdev->channel].device[sdev->id];
	}
	else {
		ata_dev = &ap->link.device[sdev->id];
	}

	*handle = ata_dev_acpi_handle(ata_dev);

	if (!*handle)
		return -ENODEV;

	return 0;
}

static int is_ata_port(const struct device *dev)
{
	return dev->type == &ata_port_type;
}

static struct ata_port *dev_to_ata_port(struct device *dev)
{
	while (!is_ata_port(dev)) {
		if (!dev->parent)
			return NULL;
		dev = dev->parent;
	}
	return to_ata_port(dev);
}

static int ata_acpi_find_device(struct device *dev, acpi_handle *handle)
{
	struct ata_port *ap = dev_to_ata_port(dev);

	if (!ap)
		return -ENODEV;

	if (!compat_pci_ata(ap))
		return -ENODEV;

	if (scsi_is_host_device(dev))
		return ata_acpi_bind_host(ap, handle);
	else if (scsi_is_sdev_device(dev)) {
		struct scsi_device *sdev = to_scsi_device(dev);

		return ata_acpi_bind_device(ap, sdev, handle);
	} else
		return -ENODEV;
}

static int ata_acpi_find_dummy(struct device *dev, acpi_handle *handle)
{
	return -ENODEV;
}

static struct acpi_bus_type ata_acpi_bus = {
	.find_bridge = ata_acpi_find_dummy,
	.find_device = ata_acpi_find_device,
};

int ata_acpi_register(void)
{
	return scsi_register_acpi_bus_type(&ata_acpi_bus);
}

void ata_acpi_unregister(void)
{
	scsi_unregister_acpi_bus_type(&ata_acpi_bus);
}