aboutsummaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-i801.c
blob: 455e909bc768637a1a7f6d793f626baef082f46d (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
/*
    Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
    Philip Edelbrock <phil@netroedge.com>, and Mark D. Studebaker
    <mdsxyz123@yahoo.com>
    Copyright (C) 2007, 2008   Jean Delvare <khali@linux-fr.org>
    Copyright (C) 2010         Intel Corporation,
                               David Woodhouse <dwmw2@infradead.org>

    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 of the License, 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; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

/*
  Supports the following Intel I/O Controller Hubs (ICH):

                                  I/O                     Block   I2C
                                  region  SMBus   Block   proc.   block
  Chip name             PCI ID    size    PEC     buffer  call    read
  ----------------------------------------------------------------------
  82801AA  (ICH)        0x2413     16      no      no      no      no
  82801AB  (ICH0)       0x2423     16      no      no      no      no
  82801BA  (ICH2)       0x2443     16      no      no      no      no
  82801CA  (ICH3)       0x2483     32     soft     no      no      no
  82801DB  (ICH4)       0x24c3     32     hard     yes     no      no
  82801E   (ICH5)       0x24d3     32     hard     yes     yes     yes
  6300ESB               0x25a4     32     hard     yes     yes     yes
  82801F   (ICH6)       0x266a     32     hard     yes     yes     yes
  6310ESB/6320ESB       0x269b     32     hard     yes     yes     yes
  82801G   (ICH7)       0x27da     32     hard     yes     yes     yes
  82801H   (ICH8)       0x283e     32     hard     yes     yes     yes
  82801I   (ICH9)       0x2930     32     hard     yes     yes     yes
  EP80579 (Tolapai)     0x5032     32     hard     yes     yes     yes
  ICH10                 0x3a30     32     hard     yes     yes     yes
  ICH10                 0x3a60     32     hard     yes     yes     yes
  5/3400 Series (PCH)   0x3b30     32     hard     yes     yes     yes
  6 Series (PCH)        0x1c22     32     hard     yes     yes     yes
  Patsburg (PCH)        0x1d22     32     hard     yes     yes     yes
  Patsburg (PCH) IDF    0x1d70     32     hard     yes     yes     yes
  Patsburg (PCH) IDF    0x1d71     32     hard     yes     yes     yes
  Patsburg (PCH) IDF    0x1d72     32     hard     yes     yes     yes
  DH89xxCC (PCH)        0x2330     32     hard     yes     yes     yes

  Features supported by this driver:
  Software PEC                     no
  Hardware PEC                     yes
  Block buffer                     yes
  Block process call transaction   no
  I2C block read transaction       yes  (doesn't use the block buffer)
  Slave mode                       no

  See the file Documentation/i2c/busses/i2c-i801 for details.
*/

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/dmi.h>
#include <linux/slab.h>

/* I801 SMBus address offsets */
#define SMBHSTSTS(p)	(0 + (p)->smba)
#define SMBHSTCNT(p)	(2 + (p)->smba)
#define SMBHSTCMD(p)	(3 + (p)->smba)
#define SMBHSTADD(p)	(4 + (p)->smba)
#define SMBHSTDAT0(p)	(5 + (p)->smba)
#define SMBHSTDAT1(p)	(6 + (p)->smba)
#define SMBBLKDAT(p)	(7 + (p)->smba)
#define SMBPEC(p)	(8 + (p)->smba)		/* ICH3 and later */
#define SMBAUXSTS(p)	(12 + (p)->smba)	/* ICH4 and later */
#define SMBAUXCTL(p)	(13 + (p)->smba)	/* ICH4 and later */

/* PCI Address Constants */
#define SMBBAR		4
#define SMBHSTCFG	0x040

/* Host configuration bits for SMBHSTCFG */
#define SMBHSTCFG_HST_EN	1
#define SMBHSTCFG_SMB_SMI_EN	2
#define SMBHSTCFG_I2C_EN	4

/* Auxiliary control register bits, ICH4+ only */
#define SMBAUXCTL_CRC		1
#define SMBAUXCTL_E32B		2

/* kill bit for SMBHSTCNT */
#define SMBHSTCNT_KILL		2

/* Other settings */
#define MAX_TIMEOUT		100
#define ENABLE_INT9		0	/* set to 0x01 to enable - untested */

/* I801 command constants */
#define I801_QUICK		0x00
#define I801_BYTE		0x04
#define I801_BYTE_DATA		0x08
#define I801_WORD_DATA		0x0C
#define I801_PROC_CALL		0x10	/* unimplemented */
#define I801_BLOCK_DATA		0x14
#define I801_I2C_BLOCK_DATA	0x18	/* ICH5 and later */
#define I801_BLOCK_LAST		0x34
#define I801_I2C_BLOCK_LAST	0x38	/* ICH5 and later */
#define I801_START		0x40
#define I801_PEC_EN		0x80	/* ICH3 and later */

/* I801 Hosts Status register bits */
#define SMBHSTSTS_BYTE_DONE	0x80
#define SMBHSTSTS_INUSE_STS	0x40
#define SMBHSTSTS_SMBALERT_STS	0x20
#define SMBHSTSTS_FAILED	0x10
#define SMBHSTSTS_BUS_ERR	0x08
#define SMBHSTSTS_DEV_ERR	0x04
#define SMBHSTSTS_INTR		0x02
#define SMBHSTSTS_HOST_BUSY	0x01

#define STATUS_FLAGS		(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_FAILED | \
				 SMBHSTSTS_BUS_ERR | SMBHSTSTS_DEV_ERR | \
				 SMBHSTSTS_INTR)

/* Older devices have their ID defined in <linux/pci_ids.h> */
#define PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS	0x1c22
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS	0x1d22
/* Patsburg also has three 'Integrated Device Function' SMBus controllers */
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0	0x1d70
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1	0x1d71
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2	0x1d72
#define PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS	0x2330
#define PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS	0x3b30

struct i801_priv {
	struct i2c_adapter adapter;
	unsigned long smba;
	unsigned char original_hstcfg;
	struct pci_dev *pci_dev;
	unsigned int features;
};

static struct pci_driver i801_driver;

#define FEATURE_SMBUS_PEC	(1 << 0)
#define FEATURE_BLOCK_BUFFER	(1 << 1)
#define FEATURE_BLOCK_PROC	(1 << 2)
#define FEATURE_I2C_BLOCK_READ	(1 << 3)

static const char *i801_feature_names[] = {
	"SMBus PEC",
	"Block buffer",
	"Block process call",
	"I2C block read",
};

static unsigned int disable_features;
module_param(disable_features, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(disable_features, "Disable selected driver features");

/* Make sure the SMBus host is ready to start transmitting.
   Return 0 if it is, -EBUSY if it is not. */
static int i801_check_pre(struct i801_priv *priv)
{
	int status;

	status = inb_p(SMBHSTSTS(priv));
	if (status & SMBHSTSTS_HOST_BUSY) {
		dev_err(&priv->pci_dev->dev, "SMBus is busy, can't use it!\n");
		return -EBUSY;
	}

	status &= STATUS_FLAGS;
	if (status) {
		dev_dbg(&priv->pci_dev->dev, "Clearing status flags (%02x)\n",
			status);
		outb_p(status, SMBHSTSTS(priv));
		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
		if (status) {
			dev_err(&priv->pci_dev->dev,
				"Failed clearing status flags (%02x)\n",
				status);
			return -EBUSY;
		}
	}

	return 0;
}

/* Convert the status register to an error code, and clear it. */
static int i801_check_post(struct i801_priv *priv, int status, int timeout)
{
	int result = 0;

	/* If the SMBus is still busy, we give up */
	if (timeout) {
		dev_err(&priv->pci_dev->dev, "Transaction timeout\n");
		/* try to stop the current command */
		dev_dbg(&priv->pci_dev->dev, "Terminating the current operation\n");
		outb_p(inb_p(SMBHSTCNT(priv)) | SMBHSTCNT_KILL,
		       SMBHSTCNT(priv));
		msleep(1);
		outb_p(inb_p(SMBHSTCNT(priv)) & (~SMBHSTCNT_KILL),
		       SMBHSTCNT(priv));

		/* Check if it worked */
		status = inb_p(SMBHSTSTS(priv));
		if ((status & SMBHSTSTS_HOST_BUSY) ||
		    !(status & SMBHSTSTS_FAILED))
			dev_err(&priv->pci_dev->dev,
				"Failed terminating the transaction\n");
		outb_p(STATUS_FLAGS, SMBHSTSTS(priv));
		return -ETIMEDOUT;
	}

	if (status & SMBHSTSTS_FAILED) {
		result = -EIO;
		dev_err(&priv->pci_dev->dev, "Transaction failed\n");
	}
	if (status & SMBHSTSTS_DEV_ERR) {
		result = -ENXIO;
		dev_dbg(&priv->pci_dev->dev, "No response\n");
	}
	if (status & SMBHSTSTS_BUS_ERR) {
		result = -EAGAIN;
		dev_dbg(&priv->pci_dev->dev, "Lost arbitration\n");
	}

	if (result) {
		/* Clear error flags */
		outb_p(status & STATUS_FLAGS, SMBHSTSTS(priv));
		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
		if (status) {
			dev_warn(&priv->pci_dev->dev, "Failed clearing status "
				 "flags at end of transaction (%02x)\n",
				 status);
		}
	}

	return result;
}

static int i801_transaction(struct i801_priv *priv, int xact)
{
	int status;
	int result;
	int timeout = 0;

	result = i801_check_pre(priv);
	if (result < 0)
		return result;

	/* the current contents of SMBHSTCNT can be overwritten, since PEC,
	 * INTREN, SMBSCMD are passed in xact */
	outb_p(xact | I801_START, SMBHSTCNT(priv));

	/* We will always wait for a fraction of a second! */
	do {
		msleep(1);
		status = inb_p(SMBHSTSTS(priv));
	} while ((status & SMBHSTSTS_HOST_BUSY) && (timeout++ < MAX_TIMEOUT));

	result = i801_check_post(priv, status, timeout > MAX_TIMEOUT);
	if (result < 0)
		return result;

	outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
	return 0;
}

/* wait for INTR bit as advised by Intel */
static void i801_wait_hwpec(struct i801_priv *priv)
{
	int timeout = 0;
	int status;

	do {
		msleep(1);
		status = inb_p(SMBHSTSTS(priv));
	} while ((!(status & SMBHSTSTS_INTR))
		 && (timeout++ < MAX_TIMEOUT));

	if (timeout > MAX_TIMEOUT)
		dev_dbg(&priv->pci_dev->dev, "PEC Timeout!\n");

	outb_p(status, SMBHSTSTS(priv));
}

static int i801_block_transaction_by_block(struct i801_priv *priv,
					   union i2c_smbus_data *data,
					   char read_write, int hwpec)
{
	int i, len;
	int status;

	inb_p(SMBHSTCNT(priv)); /* reset the data buffer index */

	/* Use 32-byte buffer to process this transaction */
	if (read_write == I2C_SMBUS_WRITE) {
		len = data->block[0];
		outb_p(len, SMBHSTDAT0(priv));
		for (i = 0; i < len; i++)
			outb_p(data->block[i+1], SMBBLKDAT(priv));
	}

	status = i801_transaction(priv, I801_BLOCK_DATA | ENABLE_INT9 |
				  I801_PEC_EN * hwpec);
	if (status)
		return status;

	if (read_write == I2C_SMBUS_READ) {
		len = inb_p(SMBHSTDAT0(priv));
		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
			return -EPROTO;

		data->block[0] = len;
		for (i = 0; i < len; i++)
			data->block[i + 1] = inb_p(SMBBLKDAT(priv));
	}
	return 0;
}

static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
					       union i2c_smbus_data *data,
					       char read_write, int command,
					       int hwpec)
{
	int i, len;
	int smbcmd;
	int status;
	int result;
	int timeout;

	result = i801_check_pre(priv);
	if (result < 0)
		return result;

	len = data->block[0];

	if (read_write == I2C_SMBUS_WRITE) {
		outb_p(len, SMBHSTDAT0(priv));
		outb_p(data->block[1], SMBBLKDAT(priv));
	}

	for (i = 1; i <= len; i++) {
		if (i == len && read_write == I2C_SMBUS_READ) {
			if (command == I2C_SMBUS_I2C_BLOCK_DATA)
				smbcmd = I801_I2C_BLOCK_LAST;
			else
				smbcmd = I801_BLOCK_LAST;
		} else {
			if (command == I2C_SMBUS_I2C_BLOCK_DATA
			 && read_write == I2C_SMBUS_READ)
				smbcmd = I801_I2C_BLOCK_DATA;
			else
				smbcmd = I801_BLOCK_DATA;
		}
		outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT(priv));

		if (i == 1)
			outb_p(inb(SMBHSTCNT(priv)) | I801_START,
			       SMBHSTCNT(priv));

		/* We will always wait for a fraction of a second! */
		timeout = 0;
		do {
			msleep(1);
			status = inb_p(SMBHSTSTS(priv));
		} while ((!(status & SMBHSTSTS_BYTE_DONE))
			 && (timeout++ < MAX_TIMEOUT));

		result = i801_check_post(priv, status, timeout > MAX_TIMEOUT);
		if (result < 0)
			return result;

		if (i == 1 && read_write == I2C_SMBUS_READ
		 && command != I2C_SMBUS_I2C_BLOCK_DATA) {
			len = inb_p(SMBHSTDAT0(priv));
			if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
				dev_err(&priv->pci_dev->dev,
					"Illegal SMBus block read size %d\n",
					len);
				/* Recover */
				while (inb_p(SMBHSTSTS(priv)) &
				       SMBHSTSTS_HOST_BUSY)
					outb_p(SMBHSTSTS_BYTE_DONE,
					       SMBHSTSTS(priv));
				outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
				return -EPROTO;
			}
			data->block[0] = len;
		}

		/* Retrieve/store value in SMBBLKDAT */
		if (read_write == I2C_SMBUS_READ)
			data->block[i] = inb_p(SMBBLKDAT(priv));
		if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
			outb_p(data->block[i+1], SMBBLKDAT(priv));

		/* signals SMBBLKDAT ready */
		outb_p(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR, SMBHSTSTS(priv));
	}

	return 0;
}

static int i801_set_block_buffer_mode(struct i801_priv *priv)
{
	outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_E32B, SMBAUXCTL(priv));
	if ((inb_p(SMBAUXCTL(priv)) & SMBAUXCTL_E32B) == 0)
		return -EIO;
	return 0;
}

/* Block transaction function */
static int i801_block_transaction(struct i801_priv *priv,
				  union i2c_smbus_data *data, char read_write,
				  int command, int hwpec)
{
	int result = 0;
	unsigned char hostc;

	if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
		if (read_write == I2C_SMBUS_WRITE) {
			/* set I2C_EN bit in configuration register */
			pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &hostc);
			pci_write_config_byte(priv->pci_dev, SMBHSTCFG,
					      hostc | SMBHSTCFG_I2C_EN);
		} else if (!(priv->features & FEATURE_I2C_BLOCK_READ)) {
			dev_err(&priv->pci_dev->dev,
				"I2C block read is unsupported!\n");
			return -EOPNOTSUPP;
		}
	}

	if (read_write == I2C_SMBUS_WRITE
	 || command == I2C_SMBUS_I2C_BLOCK_DATA) {
		if (data->block[0] < 1)
			data->block[0] = 1;
		if (data->block[0] > I2C_SMBUS_BLOCK_MAX)
			data->block[0] = I2C_SMBUS_BLOCK_MAX;
	} else {
		data->block[0] = 32;	/* max for SMBus block reads */
	}

	/* Experience has shown that the block buffer can only be used for
	   SMBus (not I2C) block transactions, even though the datasheet
	   doesn't mention this limitation. */
	if ((priv->features & FEATURE_BLOCK_BUFFER)
	 && command != I2C_SMBUS_I2C_BLOCK_DATA
	 && i801_set_block_buffer_mode(priv) == 0)
		result = i801_block_transaction_by_block(priv, data,
							 read_write, hwpec);
	else
		result = i801_block_transaction_byte_by_byte(priv, data,
							     read_write,
							     command, hwpec);

	if (result == 0 && hwpec)
		i801_wait_hwpec(priv);

	if (command == I2C_SMBUS_I2C_BLOCK_DATA
	 && read_write == I2C_SMBUS_WRITE) {
		/* restore saved configuration register value */
		pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hostc);
	}
	return result;
}

/* Return negative errno on error. */
static s32 i801_access(struct i2c_adapter *adap, u16 addr,
		       unsigned short flags, char read_write, u8 command,
		       int size, union i2c_smbus_data *data)
{
	int hwpec;
	int block = 0;
	int ret, xact = 0;
	struct i801_priv *priv = i2c_get_adapdata(adap);

	hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
		&& size != I2C_SMBUS_QUICK
		&& size != I2C_SMBUS_I2C_BLOCK_DATA;

	switch (size) {
	case I2C_SMBUS_QUICK:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD(priv));
		xact = I801_QUICK;
		break;
	case I2C_SMBUS_BYTE:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD(priv));
		if (read_write == I2C_SMBUS_WRITE)
			outb_p(command, SMBHSTCMD(priv));
		xact = I801_BYTE;
		break;
	case I2C_SMBUS_BYTE_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD(priv));
		outb_p(command, SMBHSTCMD(priv));
		if (read_write == I2C_SMBUS_WRITE)
			outb_p(data->byte, SMBHSTDAT0(priv));
		xact = I801_BYTE_DATA;
		break;
	case I2C_SMBUS_WORD_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD(priv));
		outb_p(command, SMBHSTCMD(priv));
		if (read_write == I2C_SMBUS_WRITE) {
			outb_p(data->word & 0xff, SMBHSTDAT0(priv));
			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv));
		}
		xact = I801_WORD_DATA;
		break;
	case I2C_SMBUS_BLOCK_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD(priv));
		outb_p(command, SMBHSTCMD(priv));
		block = 1;
		break;
	case I2C_SMBUS_I2C_BLOCK_DATA:
		/* NB: page 240 of ICH5 datasheet shows that the R/#W
		 * bit should be cleared here, even when reading */
		outb_p((addr & 0x7f) << 1, SMBHSTADD(priv));
		if (read_write == I2C_SMBUS_READ) {
			/* NB: page 240 of ICH5 datasheet also shows
			 * that DATA1 is the cmd field when reading */
			outb_p(command, SMBHSTDAT1(priv));
		} else
			outb_p(command, SMBHSTCMD(priv));
		block = 1;
		break;
	default:
		dev_err(&priv->pci_dev->dev, "Unsupported transaction %d\n",
			size);
		return -EOPNOTSUPP;
	}

	if (hwpec)	/* enable/disable hardware PEC */
		outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_CRC, SMBAUXCTL(priv));
	else
		outb_p(inb_p(SMBAUXCTL(priv)) & (~SMBAUXCTL_CRC),
		       SMBAUXCTL(priv));

	if (block)
		ret = i801_block_transaction(priv, data, read_write, size,
					     hwpec);
	else
		ret = i801_transaction(priv, xact | ENABLE_INT9);

	/* Some BIOSes don't like it when PEC is enabled at reboot or resume
	   time, so we forcibly disable it after every transaction. Turn off
	   E32B for the same reason. */
	if (hwpec || block)
		outb_p(inb_p(SMBAUXCTL(priv)) &
		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));

	if (block)
		return ret;
	if (ret)
		return ret;
	if ((read_write == I2C_SMBUS_WRITE) || (xact == I801_QUICK))
		return 0;

	switch (xact & 0x7f) {
	case I801_BYTE:	/* Result put in SMBHSTDAT0 */
	case I801_BYTE_DATA:
		data->byte = inb_p(SMBHSTDAT0(priv));
		break;
	case I801_WORD_DATA:
		data->word = inb_p(SMBHSTDAT0(priv)) +
			     (inb_p(SMBHSTDAT1(priv)) << 8);
		break;
	}
	return 0;
}


static u32 i801_func(struct i2c_adapter *adapter)
{
	struct i801_priv *priv = i2c_get_adapdata(adapter);

	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
	       I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
	       I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK |
	       ((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
	       ((priv->features & FEATURE_I2C_BLOCK_READ) ?
		I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0);
}

static const struct i2c_algorithm smbus_algorithm = {
	.smbus_xfer	= i801_access,
	.functionality	= i801_func,
};

static const struct pci_device_id i801_ids[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_3) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_3) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_2) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_3) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_3) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_3) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_4) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_16) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_17) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_17) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH8_5) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH9_6) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EP80579_1) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_4) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2) },
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS) },
	{ 0, }
};

MODULE_DEVICE_TABLE(pci, i801_ids);

#if defined CONFIG_INPUT_APANEL || defined CONFIG_INPUT_APANEL_MODULE
static unsigned char apanel_addr;

/* Scan the system ROM for the signature "FJKEYINF" */
static __init const void __iomem *bios_signature(const void __iomem *bios)
{
	ssize_t offset;
	const unsigned char signature[] = "FJKEYINF";

	for (offset = 0; offset < 0x10000; offset += 0x10) {
		if (check_signature(bios + offset, signature,
				    sizeof(signature)-1))
			return bios + offset;
	}
	return NULL;
}

static void __init input_apanel_init(void)
{
	void __iomem *bios;
	const void __iomem *p;

	bios = ioremap(0xF0000, 0x10000); /* Can't fail */
	p = bios_signature(bios);
	if (p) {
		/* just use the first address */
		apanel_addr = readb(p + 8 + 3) >> 1;
	}
	iounmap(bios);
}
#else
static void __init input_apanel_init(void) {}
#endif

#if defined CONFIG_SENSORS_FSCHMD || defined CONFIG_SENSORS_FSCHMD_MODULE
struct dmi_onboard_device_info {
	const char *name;
	u8 type;
	unsigned short i2c_addr;
	const char *i2c_type;
};

static struct dmi_onboard_device_info __devinitdata dmi_devices[] = {
	{ "Syleus", DMI_DEV_TYPE_OTHER, 0x73, "fscsyl" },
	{ "Hermes", DMI_DEV_TYPE_OTHER, 0x73, "fscher" },
	{ "Hades",  DMI_DEV_TYPE_OTHER, 0x73, "fschds" },
};

static void __devinit dmi_check_onboard_device(u8 type, const char *name,
					       struct i2c_adapter *adap)
{
	int i;
	struct i2c_board_info info;

	for (i = 0; i < ARRAY_SIZE(dmi_devices); i++) {
		/* & ~0x80, ignore enabled/disabled bit */
		if ((type & ~0x80) != dmi_devices[i].type)
			continue;
		if (strcasecmp(name, dmi_devices[i].name))
			continue;

		memset(&info, 0, sizeof(struct i2c_board_info));
		info.addr = dmi_devices[i].i2c_addr;
		strlcpy(info.type, dmi_devices[i].i2c_type, I2C_NAME_SIZE);
		i2c_new_device(adap, &info);
		break;
	}
}

/* We use our own function to check for onboard devices instead of
   dmi_find_device() as some buggy BIOS's have the devices we are interested
   in marked as disabled */
static void __devinit dmi_check_onboard_devices(const struct dmi_header *dm,
						void *adap)
{
	int i, count;

	if (dm->type != 10)
		return;

	count = (dm->length - sizeof(struct dmi_header)) / 2;
	for (i = 0; i < count; i++) {
		const u8 *d = (char *)(dm + 1) + (i * 2);
		const char *name = ((char *) dm) + dm->length;
		u8 type = d[0];
		u8 s = d[1];

		if (!s)
			continue;
		s--;
		while (s > 0 && name[0]) {
			name += strlen(name) + 1;
			s--;
		}
		if (name[0] == 0) /* Bogus string reference */
			continue;

		dmi_check_onboard_device(type, name, adap);
	}
}
#endif

static int __devinit i801_probe(struct pci_dev *dev,
				const struct pci_device_id *id)
{
	unsigned char temp;
	int err, i;
	struct i801_priv *priv;

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	i2c_set_adapdata(&priv->adapter, priv);
	priv->adapter.owner = THIS_MODULE;
	priv->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
	priv->adapter.algo = &smbus_algorithm;

	priv->pci_dev = dev;
	switch (dev->device) {
	default:
		priv->features |= FEATURE_I2C_BLOCK_READ;
		/* fall through */
	case PCI_DEVICE_ID_INTEL_82801DB_3:
		priv->features |= FEATURE_SMBUS_PEC;
		priv->features |= FEATURE_BLOCK_BUFFER;
		/* fall through */
	case PCI_DEVICE_ID_INTEL_82801CA_3:
	case PCI_DEVICE_ID_INTEL_82801BA_2:
	case PCI_DEVICE_ID_INTEL_82801AB_3:
	case PCI_DEVICE_ID_INTEL_82801AA_3:
		break;
	}

	/* Disable features on user request */
	for (i = 0; i < ARRAY_SIZE(i801_feature_names); i++) {
		if (priv->features & disable_features & (1 << i))
			dev_notice(&dev->dev, "%s disabled by user\n",
				   i801_feature_names[i]);
	}
	priv->features &= ~disable_features;

	err = pci_enable_device(dev);
	if (err) {
		dev_err(&dev->dev, "Failed to enable SMBus PCI device (%d)\n",
			err);
		goto exit;
	}

	/* Determine the address of the SMBus area */
	priv->smba = pci_resource_start(dev, SMBBAR);
	if (!priv->smba) {
		dev_err(&dev->dev, "SMBus base address uninitialized, "
			"upgrade BIOS\n");
		err = -ENODEV;
		goto exit;
	}

	err = acpi_check_resource_conflict(&dev->resource[SMBBAR]);
	if (err) {
		err = -ENODEV;
		goto exit;
	}

	err = pci_request_region(dev, SMBBAR, i801_driver.name);
	if (err) {
		dev_err(&dev->dev, "Failed to request SMBus region "
			"0x%lx-0x%Lx\n", priv->smba,
			(unsigned long long)pci_resource_end(dev, SMBBAR));
		goto exit;
	}

	pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &temp);
	priv->original_hstcfg = temp;
	temp &= ~SMBHSTCFG_I2C_EN;	/* SMBus timing */
	if (!(temp & SMBHSTCFG_HST_EN)) {
		dev_info(&dev->dev, "Enabling SMBus device\n");
		temp |= SMBHSTCFG_HST_EN;
	}
	pci_write_config_byte(priv->pci_dev, SMBHSTCFG, temp);

	if (temp & SMBHSTCFG_SMB_SMI_EN)
		dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
	else
		dev_dbg(&dev->dev, "SMBus using PCI Interrupt\n");

	/* Clear special mode bits */
	if (priv->features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
		outb_p(inb_p(SMBAUXCTL(priv)) &
		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));

	/* set up the sysfs linkage to our parent device */
	priv->adapter.dev.parent = &dev->dev;

	/* Retry up to 3 times on lost arbitration */
	priv->adapter.retries = 3;

	snprintf(priv->adapter.name, sizeof(priv->adapter.name),
		"SMBus I801 adapter at %04lx", priv->smba);
	err = i2c_add_adapter(&priv->adapter);
	if (err) {
		dev_err(&dev->dev, "Failed to add SMBus adapter\n");
		goto exit_release;
	}

	/* Register optional slaves */
#if defined CONFIG_INPUT_APANEL || defined CONFIG_INPUT_APANEL_MODULE
	if (apanel_addr) {
		struct i2c_board_info info;

		memset(&info, 0, sizeof(struct i2c_board_info));
		info.addr = apanel_addr;
		strlcpy(info.type, "fujitsu_apanel", I2C_NAME_SIZE);
		i2c_new_device(&priv->adapter, &info);
	}
#endif
#if defined CONFIG_SENSORS_FSCHMD || defined CONFIG_SENSORS_FSCHMD_MODULE
	if (dmi_name_in_vendors("FUJITSU"))
		dmi_walk(dmi_check_onboard_devices, &priv->adapter);
#endif

	pci_set_drvdata(dev, priv);
	return 0;

exit_release:
	pci_release_region(dev, SMBBAR);
exit:
	kfree(priv);
	return err;
}

static void __devexit i801_remove(struct pci_dev *dev)
{
	struct i801_priv *priv = pci_get_drvdata(dev);

	i2c_del_adapter(&priv->adapter);
	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
	pci_release_region(dev, SMBBAR);
	pci_set_drvdata(dev, NULL);
	kfree(priv);
	/*
	 * do not call pci_disable_device(dev) since it can cause hard hangs on
	 * some systems during power-off (eg. Fujitsu-Siemens Lifebook E8010)
	 */
}

#ifdef CONFIG_PM
static int i801_suspend(struct pci_dev *dev, pm_message_t mesg)
{
	struct i801_priv *priv = pci_get_drvdata(dev);

	pci_save_state(dev);
	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
	pci_set_power_state(dev, pci_choose_state(dev, mesg));
	return 0;
}

static int i801_resume(struct pci_dev *dev)
{
	pci_set_power_state(dev, PCI_D0);
	pci_restore_state(dev);
	return pci_enable_device(dev);
}
#else
#define i801_suspend NULL
#define i801_resume NULL
#endif

static struct pci_driver i801_driver = {
	.name		= "i801_smbus",
	.id_table	= i801_ids,
	.probe		= i801_probe,
	.remove		= __devexit_p(i801_remove),
	.suspend	= i801_suspend,
	.resume		= i801_resume,
};

static int __init i2c_i801_init(void)
{
	input_apanel_init();
	return pci_register_driver(&i801_driver);
}

static void __exit i2c_i801_exit(void)
{
	pci_unregister_driver(&i801_driver);
}

MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>, "
	      "Jean Delvare <khali@linux-fr.org>");
MODULE_DESCRIPTION("I801 SMBus driver");
MODULE_LICENSE("GPL");

module_init(i2c_i801_init);
module_exit(i2c_i801_exit);