summaryrefslogtreecommitdiffstats
path: root/drivers/hwmon/vt8231.c
blob: 5bc57275cae8e6e8a700373d1670510e442403e9 (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
/*
	vt8231.c - Part of lm_sensors, Linux kernel modules
				for hardware monitoring

	Copyright (c) 2005 Roger Lucas <vt8231@hiddenengine.co.uk>
	Copyright (c) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
			   Aaron M. Marsh <amarsh@sdf.lonestar.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 VIA VT8231 South Bridge embedded sensors
*/

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/jiffies.h>
#include <linux/platform_device.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/hwmon-vid.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <asm/io.h>

static int force_addr;
module_param(force_addr, int, 0);
MODULE_PARM_DESC(force_addr, "Initialize the base address of the sensors");

static struct platform_device *pdev;

#define VT8231_EXTENT 0x80
#define VT8231_BASE_REG 0x70
#define VT8231_ENABLE_REG 0x74

/* The VT8231 registers

   The reset value for the input channel configuration is used (Reg 0x4A=0x07)
   which sets the selected inputs marked with '*' below if multiple options are
   possible:

	            Voltage Mode	  Temperature Mode
	Sensor	      Linux Id	      Linux Id        VIA Id
	--------      --------	      --------        ------
	CPU Diode	N/A		temp1		0
	UIC1		in0		temp2 *		1
	UIC2		in1 *		temp3   	2
	UIC3		in2 *		temp4		3
	UIC4		in3 *		temp5		4
	UIC5		in4 *		temp6		5
	3.3V		in5		N/A

   Note that the BIOS may set the configuration register to a different value
   to match the motherboard configuration.
*/

/* fans numbered 0-1 */
#define VT8231_REG_FAN_MIN(nr)	(0x3b + (nr))
#define VT8231_REG_FAN(nr)	(0x29 + (nr))

/* Voltage inputs numbered 0-5 */

static const u8 regvolt[]    = { 0x21, 0x22, 0x23, 0x24, 0x25, 0x26 };
static const u8 regvoltmax[] = { 0x3d, 0x2b, 0x2d, 0x2f, 0x31, 0x33 };
static const u8 regvoltmin[] = { 0x3e, 0x2c, 0x2e, 0x30, 0x32, 0x34 };

/* Temperatures are numbered 1-6 according to the Linux kernel specification.
**
** In the VIA datasheet, however, the temperatures are numbered from zero.
** Since it is important that this driver can easily be compared to the VIA
** datasheet, we will use the VIA numbering within this driver and map the
** kernel sysfs device name to the VIA number in the sysfs callback.
*/

#define VT8231_REG_TEMP_LOW01	0x49
#define VT8231_REG_TEMP_LOW25	0x4d

static const u8 regtemp[]    = { 0x1f, 0x21, 0x22, 0x23, 0x24, 0x25 };
static const u8 regtempmax[] = { 0x39, 0x3d, 0x2b, 0x2d, 0x2f, 0x31 };
static const u8 regtempmin[] = { 0x3a, 0x3e, 0x2c, 0x2e, 0x30, 0x32 };

#define TEMP_FROM_REG(reg)		(((253 * 4 - (reg)) * 550 + 105) / 210)
#define TEMP_MAXMIN_FROM_REG(reg)	(((253 - (reg)) * 2200 + 105) / 210)
#define TEMP_MAXMIN_TO_REG(val)		(253 - ((val) * 210 + 1100) / 2200)

#define VT8231_REG_CONFIG 0x40
#define VT8231_REG_ALARM1 0x41
#define VT8231_REG_ALARM2 0x42
#define VT8231_REG_FANDIV 0x47
#define VT8231_REG_UCH_CONFIG 0x4a
#define VT8231_REG_TEMP1_CONFIG 0x4b
#define VT8231_REG_TEMP2_CONFIG 0x4c

/* temps 0-5 as numbered in VIA datasheet - see later for mapping to Linux
** numbering
*/
#define ISTEMP(i, ch_config) ((i) == 0 ? 1 : \
			      ((ch_config) >> ((i)+1)) & 0x01)
/* voltages 0-5 */
#define ISVOLT(i, ch_config) ((i) == 5 ? 1 : \
			      !(((ch_config) >> ((i)+2)) & 0x01))

#define DIV_FROM_REG(val) (1 << (val))

/* NB  The values returned here are NOT temperatures.  The calibration curves
**     for the thermistor curves are board-specific and must go in the
**     sensors.conf file.  Temperature sensors are actually ten bits, but the
**     VIA datasheet only considers the 8 MSBs obtained from the regtemp[]
**     register.  The temperature value returned should have a magnitude of 3,
**     so we use the VIA scaling as the "true" scaling and use the remaining 2
**     LSBs as fractional precision.
**
**     All the on-chip hardware temperature comparisons for the alarms are only
**     8-bits wide, and compare against the 8 MSBs of the temperature.  The bits
**     in the registers VT8231_REG_TEMP_LOW01 and VT8231_REG_TEMP_LOW25 are
**     ignored.
*/

/******** FAN RPM CONVERSIONS ********
** This chip saturates back at 0, not at 255 like many the other chips.
** So, 0 means 0 RPM
*/
static inline u8 FAN_TO_REG(long rpm, int div)
{
	if (rpm == 0)
		return 0;
	return SENSORS_LIMIT(1310720 / (rpm * div), 1, 255);
}

#define FAN_FROM_REG(val, div) ((val) == 0 ? 0 : 1310720 / ((val) * (div)))

struct vt8231_data {
	unsigned short addr;
	const char *name;

	struct mutex update_lock;
	struct device *hwmon_dev;
	char valid;		/* !=0 if following fields are valid */
	unsigned long last_updated;	/* In jiffies */

	u8 in[6];		/* Register value */
	u8 in_max[6];		/* Register value */
	u8 in_min[6];		/* Register value */
	u16 temp[6];		/* Register value 10 bit, right aligned */
	u8 temp_max[6];		/* Register value */
	u8 temp_min[6];		/* Register value */
	u8 fan[2];		/* Register value */
	u8 fan_min[2];		/* Register value */
	u8 fan_div[2];		/* Register encoding, shifted right */
	u16 alarms;		/* Register encoding */
	u8 uch_config;
};

static struct pci_dev *s_bridge;
static int vt8231_probe(struct platform_device *pdev);
static int __devexit vt8231_remove(struct platform_device *pdev);
static struct vt8231_data *vt8231_update_device(struct device *dev);
static void vt8231_init_device(struct vt8231_data *data);

static inline int vt8231_read_value(struct vt8231_data *data, u8 reg)
{
	return inb_p(data->addr + reg);
}

static inline void vt8231_write_value(struct vt8231_data *data, u8 reg,
					u8 value)
{
	outb_p(value, data->addr + reg);
}

/* following are the sysfs callback functions */
static ssize_t show_in(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);

	return sprintf(buf, "%d\n", ((data->in[nr] - 3) * 10000) / 958);
}

static ssize_t show_in_min(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);

	return sprintf(buf, "%d\n", ((data->in_min[nr] - 3) * 10000) / 958);
}

static ssize_t show_in_max(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);

	return sprintf(buf, "%d\n", (((data->in_max[nr] - 3) * 10000) / 958));
}

static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = dev_get_drvdata(dev);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->in_min[nr] = SENSORS_LIMIT(((val * 958) / 10000) + 3, 0, 255);
	vt8231_write_value(data, regvoltmin[nr], data->in_min[nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = dev_get_drvdata(dev);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->in_max[nr] = SENSORS_LIMIT(((val * 958) / 10000) + 3, 0, 255);
	vt8231_write_value(data, regvoltmax[nr], data->in_max[nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

/* Special case for input 5 as this has 3.3V scaling built into the chip */
static ssize_t show_in5(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct vt8231_data *data = vt8231_update_device(dev);

	return sprintf(buf, "%d\n",
		(((data->in[5] - 3) * 10000 * 54) / (958 * 34)));
}

static ssize_t show_in5_min(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct vt8231_data *data = vt8231_update_device(dev);

	return sprintf(buf, "%d\n",
		(((data->in_min[5] - 3) * 10000 * 54) / (958 * 34)));
}

static ssize_t show_in5_max(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct vt8231_data *data = vt8231_update_device(dev);

	return sprintf(buf, "%d\n",
		(((data->in_max[5] - 3) * 10000 * 54) / (958 * 34)));
}

static ssize_t set_in5_min(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct vt8231_data *data = dev_get_drvdata(dev);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->in_min[5] = SENSORS_LIMIT(((val * 958 * 34) / (10000 * 54)) + 3,
					0, 255);
	vt8231_write_value(data, regvoltmin[5], data->in_min[5]);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t set_in5_max(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct vt8231_data *data = dev_get_drvdata(dev);
	unsigned long val = simple_strtoul(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->in_max[5] = SENSORS_LIMIT(((val * 958 * 34) / (10000 * 54)) + 3,
					0, 255);
	vt8231_write_value(data, regvoltmax[5], data->in_max[5]);
	mutex_unlock(&data->update_lock);
	return count;
}

#define define_voltage_sysfs(offset)				\
static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
		show_in, NULL, offset);				\
static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
		show_in_min, set_in_min, offset);		\
static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
		show_in_max, set_in_max, offset)

define_voltage_sysfs(0);
define_voltage_sysfs(1);
define_voltage_sysfs(2);
define_voltage_sysfs(3);
define_voltage_sysfs(4);

static DEVICE_ATTR(in5_input, S_IRUGO, show_in5, NULL);
static DEVICE_ATTR(in5_min, S_IRUGO | S_IWUSR, show_in5_min, set_in5_min);
static DEVICE_ATTR(in5_max, S_IRUGO | S_IWUSR, show_in5_max, set_in5_max);

/* Temperatures */
static ssize_t show_temp0(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", data->temp[0] * 250);
}

static ssize_t show_temp0_max(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", data->temp_max[0] * 1000);
}

static ssize_t show_temp0_min(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", data->temp_min[0] * 1000);
}

static ssize_t set_temp0_max(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct vt8231_data *data = dev_get_drvdata(dev);
	int val = simple_strtol(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->temp_max[0] = SENSORS_LIMIT((val + 500) / 1000, 0, 255);
	vt8231_write_value(data, regtempmax[0], data->temp_max[0]);
	mutex_unlock(&data->update_lock);
	return count;
}
static ssize_t set_temp0_min(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct vt8231_data *data = dev_get_drvdata(dev);
	int val = simple_strtol(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->temp_min[0] = SENSORS_LIMIT((val + 500) / 1000, 0, 255);
	vt8231_write_value(data, regtempmin[0], data->temp_min[0]);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
}

static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_MAXMIN_FROM_REG(data->temp_max[nr]));
}

static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", TEMP_MAXMIN_FROM_REG(data->temp_min[nr]));
}

static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = dev_get_drvdata(dev);
	int val = simple_strtol(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->temp_max[nr] = SENSORS_LIMIT(TEMP_MAXMIN_TO_REG(val), 0, 255);
	vt8231_write_value(data, regtempmax[nr], data->temp_max[nr]);
	mutex_unlock(&data->update_lock);
	return count;
}
static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = dev_get_drvdata(dev);
	int val = simple_strtol(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->temp_min[nr] = SENSORS_LIMIT(TEMP_MAXMIN_TO_REG(val), 0, 255);
	vt8231_write_value(data, regtempmin[nr], data->temp_min[nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

/* Note that these map the Linux temperature sensor numbering (1-6) to the VIA
** temperature sensor numbering (0-5)
*/
#define define_temperature_sysfs(offset)				\
static SENSOR_DEVICE_ATTR(temp##offset##_input, S_IRUGO,		\
		show_temp, NULL, offset - 1);				\
static SENSOR_DEVICE_ATTR(temp##offset##_max, S_IRUGO | S_IWUSR,	\
		show_temp_max, set_temp_max, offset - 1);		\
static SENSOR_DEVICE_ATTR(temp##offset##_max_hyst, S_IRUGO | S_IWUSR,	\
		show_temp_min, set_temp_min, offset - 1)

static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp0, NULL);
static DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, show_temp0_max, set_temp0_max);
static DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR, show_temp0_min, set_temp0_min);

define_temperature_sysfs(2);
define_temperature_sysfs(3);
define_temperature_sysfs(4);
define_temperature_sysfs(5);
define_temperature_sysfs(6);

/* Fans */
static ssize_t show_fan(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
				DIV_FROM_REG(data->fan_div[nr])));
}

static ssize_t show_fan_min(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
			DIV_FROM_REG(data->fan_div[nr])));
}

static ssize_t show_fan_div(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
}

static ssize_t set_fan_min(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	int nr = sensor_attr->index;
	struct vt8231_data *data = dev_get_drvdata(dev);
	int val = simple_strtoul(buf, NULL, 10);

	mutex_lock(&data->update_lock);
	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
	vt8231_write_value(data, VT8231_REG_FAN_MIN(nr), data->fan_min[nr]);
	mutex_unlock(&data->update_lock);
	return count;
}

static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr,
		const char *buf, size_t count)
{
	struct vt8231_data *data = dev_get_drvdata(dev);
	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
	unsigned long val = simple_strtoul(buf, NULL, 10);
	int nr = sensor_attr->index;
	int old = vt8231_read_value(data, VT8231_REG_FANDIV);
	long min = FAN_FROM_REG(data->fan_min[nr],
				 DIV_FROM_REG(data->fan_div[nr]));

	mutex_lock(&data->update_lock);
	switch (val) {
	case 1: data->fan_div[nr] = 0; break;
	case 2: data->fan_div[nr] = 1; break;
	case 4: data->fan_div[nr] = 2; break;
	case 8: data->fan_div[nr] = 3; break;
	default:
		dev_err(dev, "fan_div value %ld not supported. "
		        "Choose one of 1, 2, 4 or 8!\n", val);
		mutex_unlock(&data->update_lock);
		return -EINVAL;
	}

	/* Correct the fan minimum speed */
	data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
	vt8231_write_value(data, VT8231_REG_FAN_MIN(nr), data->fan_min[nr]);

	old = (old & 0x0f) | (data->fan_div[1] << 6) | (data->fan_div[0] << 4);
	vt8231_write_value(data, VT8231_REG_FANDIV, old);
	mutex_unlock(&data->update_lock);
	return count;
}


#define define_fan_sysfs(offset)					\
static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO,			\
		show_fan, NULL, offset - 1);				\
static SENSOR_DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
		show_fan_div, set_fan_div, offset - 1);			\
static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
		show_fan_min, set_fan_min, offset - 1)

define_fan_sysfs(1);
define_fan_sysfs(2);

/* Alarms */
static ssize_t show_alarms(struct device *dev, struct device_attribute *attr,
			   char *buf)
{
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%d\n", data->alarms);
}
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);

static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	int bitnr = to_sensor_dev_attr(attr)->index;
	struct vt8231_data *data = vt8231_update_device(dev);
	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
}
static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 11);
static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 0);
static SENSOR_DEVICE_ATTR(temp4_alarm, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(temp5_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(temp6_alarm, S_IRUGO, show_alarm, NULL, 8);
static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 11);
static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 0);
static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 1);
static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 8);
static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 2);
static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL, 6);
static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);

static ssize_t show_name(struct device *dev, struct device_attribute
			 *devattr, char *buf)
{
	struct vt8231_data *data = dev_get_drvdata(dev);
	return sprintf(buf, "%s\n", data->name);
}
static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);

static struct attribute *vt8231_attributes_temps[6][5] = {
	{
		&dev_attr_temp1_input.attr,
		&dev_attr_temp1_max_hyst.attr,
		&dev_attr_temp1_max.attr,
		&sensor_dev_attr_temp1_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_temp2_input.dev_attr.attr,
		&sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
		&sensor_dev_attr_temp2_max.dev_attr.attr,
		&sensor_dev_attr_temp2_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_temp3_input.dev_attr.attr,
		&sensor_dev_attr_temp3_max_hyst.dev_attr.attr,
		&sensor_dev_attr_temp3_max.dev_attr.attr,
		&sensor_dev_attr_temp3_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_temp4_input.dev_attr.attr,
		&sensor_dev_attr_temp4_max_hyst.dev_attr.attr,
		&sensor_dev_attr_temp4_max.dev_attr.attr,
		&sensor_dev_attr_temp4_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_temp5_input.dev_attr.attr,
		&sensor_dev_attr_temp5_max_hyst.dev_attr.attr,
		&sensor_dev_attr_temp5_max.dev_attr.attr,
		&sensor_dev_attr_temp5_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_temp6_input.dev_attr.attr,
		&sensor_dev_attr_temp6_max_hyst.dev_attr.attr,
		&sensor_dev_attr_temp6_max.dev_attr.attr,
		&sensor_dev_attr_temp6_alarm.dev_attr.attr,
		NULL
	}
};

static const struct attribute_group vt8231_group_temps[6] = {
	{ .attrs = vt8231_attributes_temps[0] },
	{ .attrs = vt8231_attributes_temps[1] },
	{ .attrs = vt8231_attributes_temps[2] },
	{ .attrs = vt8231_attributes_temps[3] },
	{ .attrs = vt8231_attributes_temps[4] },
	{ .attrs = vt8231_attributes_temps[5] },
};

static struct attribute *vt8231_attributes_volts[6][5] = {
	{
		&sensor_dev_attr_in0_input.dev_attr.attr,
		&sensor_dev_attr_in0_min.dev_attr.attr,
		&sensor_dev_attr_in0_max.dev_attr.attr,
		&sensor_dev_attr_in0_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_in1_input.dev_attr.attr,
		&sensor_dev_attr_in1_min.dev_attr.attr,
		&sensor_dev_attr_in1_max.dev_attr.attr,
		&sensor_dev_attr_in1_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_in2_input.dev_attr.attr,
		&sensor_dev_attr_in2_min.dev_attr.attr,
		&sensor_dev_attr_in2_max.dev_attr.attr,
		&sensor_dev_attr_in2_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_in3_input.dev_attr.attr,
		&sensor_dev_attr_in3_min.dev_attr.attr,
		&sensor_dev_attr_in3_max.dev_attr.attr,
		&sensor_dev_attr_in3_alarm.dev_attr.attr,
		NULL
	}, {
		&sensor_dev_attr_in4_input.dev_attr.attr,
		&sensor_dev_attr_in4_min.dev_attr.attr,
		&sensor_dev_attr_in4_max.dev_attr.attr,
		&sensor_dev_attr_in4_alarm.dev_attr.attr,
		NULL
	}, {
		&dev_attr_in5_input.attr,
		&dev_attr_in5_min.attr,
		&dev_attr_in5_max.attr,
		&sensor_dev_attr_in5_alarm.dev_attr.attr,
		NULL
	}
};

static const struct attribute_group vt8231_group_volts[6] = {
	{ .attrs = vt8231_attributes_volts[0] },
	{ .attrs = vt8231_attributes_volts[1] },
	{ .attrs = vt8231_attributes_volts[2] },
	{ .attrs = vt8231_attributes_volts[3] },
	{ .attrs = vt8231_attributes_volts[4] },
	{ .attrs = vt8231_attributes_volts[5] },
};

static struct attribute *vt8231_attributes[] = {
	&sensor_dev_attr_fan1_input.dev_attr.attr,
	&sensor_dev_attr_fan2_input.dev_attr.attr,
	&sensor_dev_attr_fan1_min.dev_attr.attr,
	&sensor_dev_attr_fan2_min.dev_attr.attr,
	&sensor_dev_attr_fan1_div.dev_attr.attr,
	&sensor_dev_attr_fan2_div.dev_attr.attr,
	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
	&dev_attr_alarms.attr,
	&dev_attr_name.attr,
	NULL
};

static const struct attribute_group vt8231_group = {
	.attrs = vt8231_attributes,
};

static struct platform_driver vt8231_driver = {
	.driver = {
		.owner	= THIS_MODULE,
		.name	= "vt8231",
	},
	.probe	= vt8231_probe,
	.remove	= __devexit_p(vt8231_remove),
};

static struct pci_device_id vt8231_pci_ids[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231_4) },
	{ 0, }
};

MODULE_DEVICE_TABLE(pci, vt8231_pci_ids);

static int __devinit vt8231_pci_probe(struct pci_dev *dev,
			 	      const struct pci_device_id *id);

static struct pci_driver vt8231_pci_driver = {
	.name		= "vt8231",
	.id_table	= vt8231_pci_ids,
	.probe		= vt8231_pci_probe,
};

static int vt8231_probe(struct platform_device *pdev)
{
	struct resource *res;
	struct vt8231_data *data;
	int err = 0, i;

	/* Reserve the ISA region */
	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
	if (!request_region(res->start, VT8231_EXTENT,
			    vt8231_driver.driver.name)) {
		dev_err(&pdev->dev, "Region 0x%lx-0x%lx already in use!\n",
			(unsigned long)res->start, (unsigned long)res->end);
		return -ENODEV;
	}

	if (!(data = kzalloc(sizeof(struct vt8231_data), GFP_KERNEL))) {
		err = -ENOMEM;
		goto exit_release;
	}

	platform_set_drvdata(pdev, data);
	data->addr = res->start;
	data->name = "vt8231";

	mutex_init(&data->update_lock);
	vt8231_init_device(data);

	/* Register sysfs hooks */
	if ((err = sysfs_create_group(&pdev->dev.kobj, &vt8231_group)))
		goto exit_free;

	/* Must update device information to find out the config field */
	data->uch_config = vt8231_read_value(data, VT8231_REG_UCH_CONFIG);

	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++) {
		if (ISTEMP(i, data->uch_config)) {
			if ((err = sysfs_create_group(&pdev->dev.kobj,
					&vt8231_group_temps[i])))
				goto exit_remove_files;
		}
	}

	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++) {
		if (ISVOLT(i, data->uch_config)) {
			if ((err = sysfs_create_group(&pdev->dev.kobj,
					&vt8231_group_volts[i])))
				goto exit_remove_files;
		}
	}

	data->hwmon_dev = hwmon_device_register(&pdev->dev);
	if (IS_ERR(data->hwmon_dev)) {
		err = PTR_ERR(data->hwmon_dev);
		goto exit_remove_files;
	}
	return 0;

exit_remove_files:
	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++)
		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_volts[i]);

	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++)
		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_temps[i]);

	sysfs_remove_group(&pdev->dev.kobj, &vt8231_group);

exit_free:
	platform_set_drvdata(pdev, NULL);
	kfree(data);

exit_release:
	release_region(res->start, VT8231_EXTENT);
	return err;
}

static int __devexit vt8231_remove(struct platform_device *pdev)
{
	struct vt8231_data *data = platform_get_drvdata(pdev);
	int i;

	hwmon_device_unregister(data->hwmon_dev);

	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++)
		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_volts[i]);

	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++)
		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_temps[i]);

	sysfs_remove_group(&pdev->dev.kobj, &vt8231_group);

	release_region(data->addr, VT8231_EXTENT);
	platform_set_drvdata(pdev, NULL);
	kfree(data);
	return 0;
}

static void vt8231_init_device(struct vt8231_data *data)
{
	vt8231_write_value(data, VT8231_REG_TEMP1_CONFIG, 0);
	vt8231_write_value(data, VT8231_REG_TEMP2_CONFIG, 0);
}

static struct vt8231_data *vt8231_update_device(struct device *dev)
{
	struct vt8231_data *data = dev_get_drvdata(dev);
	int i;
	u16 low;

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
	    || !data->valid) {
		for (i = 0; i < 6; i++) {
			if (ISVOLT(i, data->uch_config)) {
				data->in[i] = vt8231_read_value(data,
						regvolt[i]);
				data->in_min[i] = vt8231_read_value(data,
						regvoltmin[i]);
				data->in_max[i] = vt8231_read_value(data,
						regvoltmax[i]);
			}
		}
		for (i = 0; i < 2; i++) {
			data->fan[i] = vt8231_read_value(data,
						VT8231_REG_FAN(i));
			data->fan_min[i] = vt8231_read_value(data,
						VT8231_REG_FAN_MIN(i));
		}

		low = vt8231_read_value(data, VT8231_REG_TEMP_LOW01);
		low = (low >> 6) | ((low & 0x30) >> 2)
		    | (vt8231_read_value(data, VT8231_REG_TEMP_LOW25) << 4);
		for (i = 0; i < 6; i++) {
			if (ISTEMP(i, data->uch_config)) {
				data->temp[i] = (vt8231_read_value(data,
						       regtemp[i]) << 2)
						| ((low >> (2 * i)) & 0x03);
				data->temp_max[i] = vt8231_read_value(data,
						      regtempmax[i]);
				data->temp_min[i] = vt8231_read_value(data,
						      regtempmin[i]);
			}
		}

		i = vt8231_read_value(data, VT8231_REG_FANDIV);
		data->fan_div[0] = (i >> 4) & 0x03;
		data->fan_div[1] = i >> 6;
		data->alarms = vt8231_read_value(data, VT8231_REG_ALARM1) |
			(vt8231_read_value(data, VT8231_REG_ALARM2) << 8);

		/* Set alarm flags correctly */
		if (!data->fan[0] && data->fan_min[0]) {
			data->alarms |= 0x40;
		} else if (data->fan[0] && !data->fan_min[0]) {
			data->alarms &= ~0x40;
		}

		if (!data->fan[1] && data->fan_min[1]) {
			data->alarms |= 0x80;
		} else if (data->fan[1] && !data->fan_min[1]) {
			data->alarms &= ~0x80;
		}

		data->last_updated = jiffies;
		data->valid = 1;
	}

	mutex_unlock(&data->update_lock);

	return data;
}

static int __devinit vt8231_device_add(unsigned short address)
{
	struct resource res = {
		.start	= address,
		.end	= address + VT8231_EXTENT - 1,
		.name	= "vt8231",
		.flags	= IORESOURCE_IO,
	};
	int err;

	pdev = platform_device_alloc("vt8231", address);
	if (!pdev) {
		err = -ENOMEM;
		printk(KERN_ERR "vt8231: Device allocation failed\n");
		goto exit;
	}

	err = platform_device_add_resources(pdev, &res, 1);
	if (err) {
		printk(KERN_ERR "vt8231: Device resource addition failed "
		       "(%d)\n", err);
		goto exit_device_put;
	}

	err = platform_device_add(pdev);
	if (err) {
		printk(KERN_ERR "vt8231: Device addition failed (%d)\n",
		       err);
		goto exit_device_put;
	}

	return 0;

exit_device_put:
	platform_device_put(pdev);
exit:
	return err;
}

static int __devinit vt8231_pci_probe(struct pci_dev *dev,
				const struct pci_device_id *id)
{
	u16 address, val;
	if (force_addr) {
		address = force_addr & 0xff00;
		dev_warn(&dev->dev, "Forcing ISA address 0x%x\n",
			 address);

		if (PCIBIOS_SUCCESSFUL !=
		    pci_write_config_word(dev, VT8231_BASE_REG, address | 1))
			return -ENODEV;
	}

	if (PCIBIOS_SUCCESSFUL != pci_read_config_word(dev, VT8231_BASE_REG,
							&val))
		return -ENODEV;

	address = val & ~(VT8231_EXTENT - 1);
	if (address == 0) {
		dev_err(&dev->dev, "base address not set -\
				 upgrade BIOS or use force_addr=0xaddr\n");
		return -ENODEV;
	}

	if (PCIBIOS_SUCCESSFUL != pci_read_config_word(dev, VT8231_ENABLE_REG,
							&val))
		return -ENODEV;

	if (!(val & 0x0001)) {
		dev_warn(&dev->dev, "enabling sensors\n");
		if (PCIBIOS_SUCCESSFUL !=
			pci_write_config_word(dev, VT8231_ENABLE_REG,
							val | 0x0001))
			return -ENODEV;
	}

	if (platform_driver_register(&vt8231_driver))
		goto exit;

	/* Sets global pdev as a side effect */
	if (vt8231_device_add(address))
		goto exit_unregister;

	/* Always return failure here.  This is to allow other drivers to bind
	 * to this pci device.  We don't really want to have control over the
	 * pci device, we only wanted to read as few register values from it.
	 */

	/* We do, however, mark ourselves as using the PCI device to stop it
	   getting unloaded. */
	s_bridge = pci_dev_get(dev);
	return -ENODEV;

exit_unregister:
	platform_driver_unregister(&vt8231_driver);
exit:
	return -ENODEV;
}

static int __init sm_vt8231_init(void)
{
	return pci_register_driver(&vt8231_pci_driver);
}

static void __exit sm_vt8231_exit(void)
{
	pci_unregister_driver(&vt8231_pci_driver);
	if (s_bridge != NULL) {
		platform_device_unregister(pdev);
		platform_driver_unregister(&vt8231_driver);
		pci_dev_put(s_bridge);
		s_bridge = NULL;
	}
}

MODULE_AUTHOR("Roger Lucas <vt8231@hiddenengine.co.uk>");
MODULE_DESCRIPTION("VT8231 sensors");
MODULE_LICENSE("GPL");

module_init(sm_vt8231_init);
module_exit(sm_vt8231_exit);