xref: /linux/drivers/hwmon/via686a.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
1 /*
2     via686a.c - Part of lm_sensors, Linux kernel modules
3 		for hardware monitoring
4 
5     Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
6 			Kyösti Mälkki <kmalkki@cc.hut.fi>,
7 			Mark Studebaker <mdsxyz123@yahoo.com>,
8 			and Bob Dougherty <bobd@stanford.edu>
9     (Some conversion-factor data were contributed by Jonathan Teh Soon Yew
10     <j.teh@iname.com> and Alex van Kaam <darkside@chello.nl>.)
11 
12     This program is free software; you can redistribute it and/or modify
13     it under the terms of the GNU General Public License as published by
14     the Free Software Foundation; either version 2 of the License, or
15     (at your option) any later version.
16 
17     This program is distributed in the hope that it will be useful,
18     but WITHOUT ANY WARRANTY; without even the implied warranty of
19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20     GNU General Public License for more details.
21 
22     You should have received a copy of the GNU General Public License
23     along with this program; if not, write to the Free Software
24     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 */
26 
27 /*
28     Supports the Via VT82C686A, VT82C686B south bridges.
29     Reports all as a 686A.
30     Warning - only supports a single device.
31 */
32 
33 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34 
35 #include <linux/module.h>
36 #include <linux/slab.h>
37 #include <linux/pci.h>
38 #include <linux/jiffies.h>
39 #include <linux/platform_device.h>
40 #include <linux/hwmon.h>
41 #include <linux/hwmon-sysfs.h>
42 #include <linux/err.h>
43 #include <linux/init.h>
44 #include <linux/mutex.h>
45 #include <linux/sysfs.h>
46 #include <linux/acpi.h>
47 #include <linux/io.h>
48 
49 
50 /* If force_addr is set to anything different from 0, we forcibly enable
51    the device at the given address. */
52 static unsigned short force_addr;
53 module_param(force_addr, ushort, 0);
54 MODULE_PARM_DESC(force_addr,
55 		 "Initialize the base address of the sensors");
56 
57 static struct platform_device *pdev;
58 
59 /*
60    The Via 686a southbridge has a LM78-like chip integrated on the same IC.
61    This driver is a customized copy of lm78.c
62 */
63 
64 /* Many VIA686A constants specified below */
65 
66 /* Length of ISA address segment */
67 #define VIA686A_EXTENT		0x80
68 #define VIA686A_BASE_REG	0x70
69 #define VIA686A_ENABLE_REG	0x74
70 
71 /* The VIA686A registers */
72 /* ins numbered 0-4 */
73 #define VIA686A_REG_IN_MAX(nr)	(0x2b + ((nr) * 2))
74 #define VIA686A_REG_IN_MIN(nr)	(0x2c + ((nr) * 2))
75 #define VIA686A_REG_IN(nr)	(0x22 + (nr))
76 
77 /* fans numbered 1-2 */
78 #define VIA686A_REG_FAN_MIN(nr)	(0x3a + (nr))
79 #define VIA686A_REG_FAN(nr)	(0x28 + (nr))
80 
81 /* temps numbered 1-3 */
82 static const u8 VIA686A_REG_TEMP[]	= { 0x20, 0x21, 0x1f };
83 static const u8 VIA686A_REG_TEMP_OVER[]	= { 0x39, 0x3d, 0x1d };
84 static const u8 VIA686A_REG_TEMP_HYST[]	= { 0x3a, 0x3e, 0x1e };
85 /* bits 7-6 */
86 #define VIA686A_REG_TEMP_LOW1	0x4b
87 /* 2 = bits 5-4, 3 = bits 7-6 */
88 #define VIA686A_REG_TEMP_LOW23	0x49
89 
90 #define VIA686A_REG_ALARM1	0x41
91 #define VIA686A_REG_ALARM2	0x42
92 #define VIA686A_REG_FANDIV	0x47
93 #define VIA686A_REG_CONFIG	0x40
94 /* The following register sets temp interrupt mode (bits 1-0 for temp1,
95  3-2 for temp2, 5-4 for temp3).  Modes are:
96     00 interrupt stays as long as value is out-of-range
97     01 interrupt is cleared once register is read (default)
98     10 comparator mode- like 00, but ignores hysteresis
99     11 same as 00 */
100 #define VIA686A_REG_TEMP_MODE		0x4b
101 /* We'll just assume that you want to set all 3 simultaneously: */
102 #define VIA686A_TEMP_MODE_MASK		0x3F
103 #define VIA686A_TEMP_MODE_CONTINUOUS	0x00
104 
105 /* Conversions. Limit checking is only done on the TO_REG
106    variants.
107 
108 ********* VOLTAGE CONVERSIONS (Bob Dougherty) ********
109  From HWMon.cpp (Copyright 1998-2000 Jonathan Teh Soon Yew):
110  voltagefactor[0]=1.25/2628; (2628/1.25=2102.4)   // Vccp
111  voltagefactor[1]=1.25/2628; (2628/1.25=2102.4)   // +2.5V
112  voltagefactor[2]=1.67/2628; (2628/1.67=1573.7)   // +3.3V
113  voltagefactor[3]=2.6/2628;  (2628/2.60=1010.8)   // +5V
114  voltagefactor[4]=6.3/2628;  (2628/6.30=417.14)   // +12V
115  in[i]=(data[i+2]*25.0+133)*voltagefactor[i];
116  That is:
117  volts = (25*regVal+133)*factor
118  regVal = (volts/factor-133)/25
119  (These conversions were contributed by Jonathan Teh Soon Yew
120  <j.teh@iname.com>) */
121 static inline u8 IN_TO_REG(long val, int inNum)
122 {
123 	/* To avoid floating point, we multiply constants by 10 (100 for +12V).
124 	   Rounding is done (120500 is actually 133000 - 12500).
125 	   Remember that val is expressed in 0.001V/bit, which is why we divide
126 	   by an additional 10000 (100000 for +12V): 1000 for val and 10 (100)
127 	   for the constants. */
128 	if (inNum <= 1)
129 		return (u8)
130 		    SENSORS_LIMIT((val * 21024 - 1205000) / 250000, 0, 255);
131 	else if (inNum == 2)
132 		return (u8)
133 		    SENSORS_LIMIT((val * 15737 - 1205000) / 250000, 0, 255);
134 	else if (inNum == 3)
135 		return (u8)
136 		    SENSORS_LIMIT((val * 10108 - 1205000) / 250000, 0, 255);
137 	else
138 		return (u8)
139 		    SENSORS_LIMIT((val * 41714 - 12050000) / 2500000, 0, 255);
140 }
141 
142 static inline long IN_FROM_REG(u8 val, int inNum)
143 {
144 	/* To avoid floating point, we multiply constants by 10 (100 for +12V).
145 	   We also multiply them by 1000 because we want 0.001V/bit for the
146 	   output value. Rounding is done. */
147 	if (inNum <= 1)
148 		return (long) ((250000 * val + 1330000 + 21024 / 2) / 21024);
149 	else if (inNum == 2)
150 		return (long) ((250000 * val + 1330000 + 15737 / 2) / 15737);
151 	else if (inNum == 3)
152 		return (long) ((250000 * val + 1330000 + 10108 / 2) / 10108);
153 	else
154 		return (long) ((2500000 * val + 13300000 + 41714 / 2) / 41714);
155 }
156 
157 /********* FAN RPM CONVERSIONS ********/
158 /* Higher register values = slower fans (the fan's strobe gates a counter).
159  But this chip saturates back at 0, not at 255 like all the other chips.
160  So, 0 means 0 RPM */
161 static inline u8 FAN_TO_REG(long rpm, int div)
162 {
163 	if (rpm == 0)
164 		return 0;
165 	rpm = SENSORS_LIMIT(rpm, 1, 1000000);
166 	return SENSORS_LIMIT((1350000 + rpm * div / 2) / (rpm * div), 1, 255);
167 }
168 
169 #define FAN_FROM_REG(val,div) ((val)==0?0:(val)==255?0:1350000/((val)*(div)))
170 
171 /******** TEMP CONVERSIONS (Bob Dougherty) *********/
172 /* linear fits from HWMon.cpp (Copyright 1998-2000 Jonathan Teh Soon Yew)
173       if(temp<169)
174 	      return double(temp)*0.427-32.08;
175       else if(temp>=169 && temp<=202)
176 	      return double(temp)*0.582-58.16;
177       else
178 	      return double(temp)*0.924-127.33;
179 
180  A fifth-order polynomial fits the unofficial data (provided by Alex van
181  Kaam <darkside@chello.nl>) a bit better.  It also give more reasonable
182  numbers on my machine (ie. they agree with what my BIOS tells me).
183  Here's the fifth-order fit to the 8-bit data:
184  temp = 1.625093e-10*val^5 - 1.001632e-07*val^4 + 2.457653e-05*val^3 -
185 	2.967619e-03*val^2 + 2.175144e-01*val - 7.090067e+0.
186 
187  (2000-10-25- RFD: thanks to Uwe Andersen <uandersen@mayah.com> for
188  finding my typos in this formula!)
189 
190  Alas, none of the elegant function-fit solutions will work because we
191  aren't allowed to use floating point in the kernel and doing it with
192  integers doesn't provide enough precision.  So we'll do boring old
193  look-up table stuff.  The unofficial data (see below) have effectively
194  7-bit resolution (they are rounded to the nearest degree).  I'm assuming
195  that the transfer function of the device is monotonic and smooth, so a
196  smooth function fit to the data will allow us to get better precision.
197  I used the 5th-order poly fit described above and solved for
198  VIA register values 0-255.  I *10 before rounding, so we get tenth-degree
199  precision.  (I could have done all 1024 values for our 10-bit readings,
200  but the function is very linear in the useful range (0-80 deg C), so
201  we'll just use linear interpolation for 10-bit readings.)  So, tempLUT
202  is the temp at via register values 0-255: */
203 static const s16 tempLUT[] =
204 { -709, -688, -667, -646, -627, -607, -589, -570, -553, -536, -519,
205 	-503, -487, -471, -456, -442, -428, -414, -400, -387, -375,
206 	-362, -350, -339, -327, -316, -305, -295, -285, -275, -265,
207 	-255, -246, -237, -229, -220, -212, -204, -196, -188, -180,
208 	-173, -166, -159, -152, -145, -139, -132, -126, -120, -114,
209 	-108, -102, -96, -91, -85, -80, -74, -69, -64, -59, -54, -49,
210 	-44, -39, -34, -29, -25, -20, -15, -11, -6, -2, 3, 7, 12, 16,
211 	20, 25, 29, 33, 37, 42, 46, 50, 54, 59, 63, 67, 71, 75, 79, 84,
212 	88, 92, 96, 100, 104, 109, 113, 117, 121, 125, 130, 134, 138,
213 	142, 146, 151, 155, 159, 163, 168, 172, 176, 181, 185, 189,
214 	193, 198, 202, 206, 211, 215, 219, 224, 228, 232, 237, 241,
215 	245, 250, 254, 259, 263, 267, 272, 276, 281, 285, 290, 294,
216 	299, 303, 307, 312, 316, 321, 325, 330, 334, 339, 344, 348,
217 	353, 357, 362, 366, 371, 376, 380, 385, 390, 395, 399, 404,
218 	409, 414, 419, 423, 428, 433, 438, 443, 449, 454, 459, 464,
219 	469, 475, 480, 486, 491, 497, 502, 508, 514, 520, 526, 532,
220 	538, 544, 551, 557, 564, 571, 578, 584, 592, 599, 606, 614,
221 	621, 629, 637, 645, 654, 662, 671, 680, 689, 698, 708, 718,
222 	728, 738, 749, 759, 770, 782, 793, 805, 818, 830, 843, 856,
223 	870, 883, 898, 912, 927, 943, 958, 975, 991, 1008, 1026, 1044,
224 	1062, 1081, 1101, 1121, 1141, 1162, 1184, 1206, 1229, 1252,
225 	1276, 1301, 1326, 1352, 1378, 1406, 1434, 1462
226 };
227 
228 /* the original LUT values from Alex van Kaam <darkside@chello.nl>
229    (for via register values 12-240):
230 {-50,-49,-47,-45,-43,-41,-39,-38,-37,-35,-34,-33,-32,-31,
231 -30,-29,-28,-27,-26,-25,-24,-24,-23,-22,-21,-20,-20,-19,-18,-17,-17,-16,-15,
232 -15,-14,-14,-13,-12,-12,-11,-11,-10,-9,-9,-8,-8,-7,-7,-6,-6,-5,-5,-4,-4,-3,
233 -3,-2,-2,-1,-1,0,0,1,1,1,3,3,3,4,4,4,5,5,5,6,6,7,7,8,8,9,9,9,10,10,11,11,12,
234 12,12,13,13,13,14,14,15,15,16,16,16,17,17,18,18,19,19,20,20,21,21,21,22,22,
235 22,23,23,24,24,25,25,26,26,26,27,27,27,28,28,29,29,30,30,30,31,31,32,32,33,
236 33,34,34,35,35,35,36,36,37,37,38,38,39,39,40,40,41,41,42,42,43,43,44,44,45,
237 45,46,46,47,48,48,49,49,50,51,51,52,52,53,53,54,55,55,56,57,57,58,59,59,60,
238 61,62,62,63,64,65,66,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,83,84,
239 85,86,88,89,91,92,94,96,97,99,101,103,105,107,109,110};
240 
241 
242  Here's the reverse LUT.  I got it by doing a 6-th order poly fit (needed
243  an extra term for a good fit to these inverse data!) and then
244  solving for each temp value from -50 to 110 (the useable range for
245  this chip).  Here's the fit:
246  viaRegVal = -1.160370e-10*val^6 +3.193693e-08*val^5 - 1.464447e-06*val^4
247  - 2.525453e-04*val^3 + 1.424593e-02*val^2 + 2.148941e+00*val +7.275808e+01)
248  Note that n=161: */
249 static const u8 viaLUT[] =
250 { 12, 12, 13, 14, 14, 15, 16, 16, 17, 18, 18, 19, 20, 20, 21, 22, 23,
251 	23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 35, 36, 37, 39, 40,
252 	41, 43, 45, 46, 48, 49, 51, 53, 55, 57, 59, 60, 62, 64, 66,
253 	69, 71, 73, 75, 77, 79, 82, 84, 86, 88, 91, 93, 95, 98, 100,
254 	103, 105, 107, 110, 112, 115, 117, 119, 122, 124, 126, 129,
255 	131, 134, 136, 138, 140, 143, 145, 147, 150, 152, 154, 156,
256 	158, 160, 162, 164, 166, 168, 170, 172, 174, 176, 178, 180,
257 	182, 183, 185, 187, 188, 190, 192, 193, 195, 196, 198, 199,
258 	200, 202, 203, 205, 206, 207, 208, 209, 210, 211, 212, 213,
259 	214, 215, 216, 217, 218, 219, 220, 221, 222, 222, 223, 224,
260 	225, 226, 226, 227, 228, 228, 229, 230, 230, 231, 232, 232,
261 	233, 233, 234, 235, 235, 236, 236, 237, 237, 238, 238, 239,
262 	239, 240
263 };
264 
265 /* Converting temps to (8-bit) hyst and over registers
266    No interpolation here.
267    The +50 is because the temps start at -50 */
268 static inline u8 TEMP_TO_REG(long val)
269 {
270 	return viaLUT[val <= -50000 ? 0 : val >= 110000 ? 160 :
271 		      (val < 0 ? val - 500 : val + 500) / 1000 + 50];
272 }
273 
274 /* for 8-bit temperature hyst and over registers */
275 #define TEMP_FROM_REG(val)	((long)tempLUT[val] * 100)
276 
277 /* for 10-bit temperature readings */
278 static inline long TEMP_FROM_REG10(u16 val)
279 {
280 	u16 eightBits = val >> 2;
281 	u16 twoBits = val & 3;
282 
283 	/* no interpolation for these */
284 	if (twoBits == 0 || eightBits == 255)
285 		return TEMP_FROM_REG(eightBits);
286 
287 	/* do some linear interpolation */
288 	return (tempLUT[eightBits] * (4 - twoBits) +
289 		tempLUT[eightBits + 1] * twoBits) * 25;
290 }
291 
292 #define DIV_FROM_REG(val) (1 << (val))
293 #define DIV_TO_REG(val) ((val)==8?3:(val)==4?2:(val)==1?0:1)
294 
295 /* For each registered chip, we need to keep some data in memory.
296    The structure is dynamically allocated. */
297 struct via686a_data {
298 	unsigned short addr;
299 	const char *name;
300 	struct device *hwmon_dev;
301 	struct mutex update_lock;
302 	char valid;		/* !=0 if following fields are valid */
303 	unsigned long last_updated;	/* In jiffies */
304 
305 	u8 in[5];		/* Register value */
306 	u8 in_max[5];		/* Register value */
307 	u8 in_min[5];		/* Register value */
308 	u8 fan[2];		/* Register value */
309 	u8 fan_min[2];		/* Register value */
310 	u16 temp[3];		/* Register value 10 bit */
311 	u8 temp_over[3];	/* Register value */
312 	u8 temp_hyst[3];	/* Register value */
313 	u8 fan_div[2];		/* Register encoding, shifted right */
314 	u16 alarms;		/* Register encoding, combined */
315 };
316 
317 static struct pci_dev *s_bridge;	/* pointer to the (only) via686a */
318 
319 static int via686a_probe(struct platform_device *pdev);
320 static int __devexit via686a_remove(struct platform_device *pdev);
321 
322 static inline int via686a_read_value(struct via686a_data *data, u8 reg)
323 {
324 	return inb_p(data->addr + reg);
325 }
326 
327 static inline void via686a_write_value(struct via686a_data *data, u8 reg,
328 				       u8 value)
329 {
330 	outb_p(value, data->addr + reg);
331 }
332 
333 static struct via686a_data *via686a_update_device(struct device *dev);
334 static void via686a_init_device(struct via686a_data *data);
335 
336 /* following are the sysfs callback functions */
337 
338 /* 7 voltage sensors */
339 static ssize_t show_in(struct device *dev, struct device_attribute *da,
340 		char *buf) {
341 	struct via686a_data *data = via686a_update_device(dev);
342 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
343 	int nr = attr->index;
344 	return sprintf(buf, "%ld\n", IN_FROM_REG(data->in[nr], nr));
345 }
346 
347 static ssize_t show_in_min(struct device *dev, struct device_attribute *da,
348 		char *buf) {
349 	struct via686a_data *data = via686a_update_device(dev);
350 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
351 	int nr = attr->index;
352 	return sprintf(buf, "%ld\n", IN_FROM_REG(data->in_min[nr], nr));
353 }
354 
355 static ssize_t show_in_max(struct device *dev, struct device_attribute *da,
356 		char *buf) {
357 	struct via686a_data *data = via686a_update_device(dev);
358 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
359 	int nr = attr->index;
360 	return sprintf(buf, "%ld\n", IN_FROM_REG(data->in_max[nr], nr));
361 }
362 
363 static ssize_t set_in_min(struct device *dev, struct device_attribute *da,
364 		const char *buf, size_t count) {
365 	struct via686a_data *data = dev_get_drvdata(dev);
366 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
367 	int nr = attr->index;
368 	unsigned long val = simple_strtoul(buf, NULL, 10);
369 
370 	mutex_lock(&data->update_lock);
371 	data->in_min[nr] = IN_TO_REG(val, nr);
372 	via686a_write_value(data, VIA686A_REG_IN_MIN(nr),
373 			data->in_min[nr]);
374 	mutex_unlock(&data->update_lock);
375 	return count;
376 }
377 static ssize_t set_in_max(struct device *dev, struct device_attribute *da,
378 		const char *buf, size_t count) {
379 	struct via686a_data *data = dev_get_drvdata(dev);
380 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
381 	int nr = attr->index;
382 	unsigned long val = simple_strtoul(buf, NULL, 10);
383 
384 	mutex_lock(&data->update_lock);
385 	data->in_max[nr] = IN_TO_REG(val, nr);
386 	via686a_write_value(data, VIA686A_REG_IN_MAX(nr),
387 			data->in_max[nr]);
388 	mutex_unlock(&data->update_lock);
389 	return count;
390 }
391 #define show_in_offset(offset)					\
392 static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
393 		show_in, NULL, offset);				\
394 static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
395 		show_in_min, set_in_min, offset);		\
396 static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
397 		show_in_max, set_in_max, offset);
398 
399 show_in_offset(0);
400 show_in_offset(1);
401 show_in_offset(2);
402 show_in_offset(3);
403 show_in_offset(4);
404 
405 /* 3 temperatures */
406 static ssize_t show_temp(struct device *dev, struct device_attribute *da,
407 		char *buf) {
408 	struct via686a_data *data = via686a_update_device(dev);
409 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
410 	int nr = attr->index;
411 	return sprintf(buf, "%ld\n", TEMP_FROM_REG10(data->temp[nr]));
412 }
413 static ssize_t show_temp_over(struct device *dev, struct device_attribute *da,
414 		char *buf) {
415 	struct via686a_data *data = via686a_update_device(dev);
416 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
417 	int nr = attr->index;
418 	return sprintf(buf, "%ld\n", TEMP_FROM_REG(data->temp_over[nr]));
419 }
420 static ssize_t show_temp_hyst(struct device *dev, struct device_attribute *da,
421 		char *buf) {
422 	struct via686a_data *data = via686a_update_device(dev);
423 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
424 	int nr = attr->index;
425 	return sprintf(buf, "%ld\n", TEMP_FROM_REG(data->temp_hyst[nr]));
426 }
427 static ssize_t set_temp_over(struct device *dev, struct device_attribute *da,
428 		const char *buf, size_t count) {
429 	struct via686a_data *data = dev_get_drvdata(dev);
430 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
431 	int nr = attr->index;
432 	int val = simple_strtol(buf, NULL, 10);
433 
434 	mutex_lock(&data->update_lock);
435 	data->temp_over[nr] = TEMP_TO_REG(val);
436 	via686a_write_value(data, VIA686A_REG_TEMP_OVER[nr],
437 			    data->temp_over[nr]);
438 	mutex_unlock(&data->update_lock);
439 	return count;
440 }
441 static ssize_t set_temp_hyst(struct device *dev, struct device_attribute *da,
442 		const char *buf, size_t count) {
443 	struct via686a_data *data = dev_get_drvdata(dev);
444 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
445 	int nr = attr->index;
446 	int val = simple_strtol(buf, NULL, 10);
447 
448 	mutex_lock(&data->update_lock);
449 	data->temp_hyst[nr] = TEMP_TO_REG(val);
450 	via686a_write_value(data, VIA686A_REG_TEMP_HYST[nr],
451 			    data->temp_hyst[nr]);
452 	mutex_unlock(&data->update_lock);
453 	return count;
454 }
455 #define show_temp_offset(offset)					\
456 static SENSOR_DEVICE_ATTR(temp##offset##_input, S_IRUGO,		\
457 		show_temp, NULL, offset - 1);				\
458 static SENSOR_DEVICE_ATTR(temp##offset##_max, S_IRUGO | S_IWUSR,	\
459 		show_temp_over, set_temp_over, offset - 1);		\
460 static SENSOR_DEVICE_ATTR(temp##offset##_max_hyst, S_IRUGO | S_IWUSR,	\
461 		show_temp_hyst, set_temp_hyst, offset - 1);
462 
463 show_temp_offset(1);
464 show_temp_offset(2);
465 show_temp_offset(3);
466 
467 /* 2 Fans */
468 static ssize_t show_fan(struct device *dev, struct device_attribute *da,
469 		char *buf) {
470 	struct via686a_data *data = via686a_update_device(dev);
471 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
472 	int nr = attr->index;
473 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
474 				DIV_FROM_REG(data->fan_div[nr])) );
475 }
476 static ssize_t show_fan_min(struct device *dev, struct device_attribute *da,
477 		char *buf) {
478 	struct via686a_data *data = via686a_update_device(dev);
479 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
480 	int nr = attr->index;
481 	return sprintf(buf, "%d\n",
482 		FAN_FROM_REG(data->fan_min[nr], DIV_FROM_REG(data->fan_div[nr])) );
483 }
484 static ssize_t show_fan_div(struct device *dev, struct device_attribute *da,
485 		char *buf) {
486 	struct via686a_data *data = via686a_update_device(dev);
487 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
488 	int nr = attr->index;
489 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]) );
490 }
491 static ssize_t set_fan_min(struct device *dev, struct device_attribute *da,
492 		const char *buf, size_t count) {
493 	struct via686a_data *data = dev_get_drvdata(dev);
494 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
495 	int nr = attr->index;
496 	int val = simple_strtol(buf, NULL, 10);
497 
498 	mutex_lock(&data->update_lock);
499 	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
500 	via686a_write_value(data, VIA686A_REG_FAN_MIN(nr+1), data->fan_min[nr]);
501 	mutex_unlock(&data->update_lock);
502 	return count;
503 }
504 static ssize_t set_fan_div(struct device *dev, struct device_attribute *da,
505 		const char *buf, size_t count) {
506 	struct via686a_data *data = dev_get_drvdata(dev);
507 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
508 	int nr = attr->index;
509 	int val = simple_strtol(buf, NULL, 10);
510 	int old;
511 
512 	mutex_lock(&data->update_lock);
513 	old = via686a_read_value(data, VIA686A_REG_FANDIV);
514 	data->fan_div[nr] = DIV_TO_REG(val);
515 	old = (old & 0x0f) | (data->fan_div[1] << 6) | (data->fan_div[0] << 4);
516 	via686a_write_value(data, VIA686A_REG_FANDIV, old);
517 	mutex_unlock(&data->update_lock);
518 	return count;
519 }
520 
521 #define show_fan_offset(offset)						\
522 static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO,			\
523 		show_fan, NULL, offset - 1);				\
524 static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
525 		show_fan_min, set_fan_min, offset - 1);			\
526 static SENSOR_DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
527 		show_fan_div, set_fan_div, offset - 1);
528 
529 show_fan_offset(1);
530 show_fan_offset(2);
531 
532 /* Alarms */
533 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf) {
534 	struct via686a_data *data = via686a_update_device(dev);
535 	return sprintf(buf, "%u\n", data->alarms);
536 }
537 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
538 
539 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
540 			  char *buf)
541 {
542 	int bitnr = to_sensor_dev_attr(attr)->index;
543 	struct via686a_data *data = via686a_update_device(dev);
544 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
545 }
546 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0);
547 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 1);
548 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 2);
549 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
550 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 8);
551 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
552 static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 11);
553 static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 15);
554 static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL, 6);
555 static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);
556 
557 static ssize_t show_name(struct device *dev, struct device_attribute
558 			 *devattr, char *buf)
559 {
560 	struct via686a_data *data = dev_get_drvdata(dev);
561 	return sprintf(buf, "%s\n", data->name);
562 }
563 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
564 
565 static struct attribute *via686a_attributes[] = {
566 	&sensor_dev_attr_in0_input.dev_attr.attr,
567 	&sensor_dev_attr_in1_input.dev_attr.attr,
568 	&sensor_dev_attr_in2_input.dev_attr.attr,
569 	&sensor_dev_attr_in3_input.dev_attr.attr,
570 	&sensor_dev_attr_in4_input.dev_attr.attr,
571 	&sensor_dev_attr_in0_min.dev_attr.attr,
572 	&sensor_dev_attr_in1_min.dev_attr.attr,
573 	&sensor_dev_attr_in2_min.dev_attr.attr,
574 	&sensor_dev_attr_in3_min.dev_attr.attr,
575 	&sensor_dev_attr_in4_min.dev_attr.attr,
576 	&sensor_dev_attr_in0_max.dev_attr.attr,
577 	&sensor_dev_attr_in1_max.dev_attr.attr,
578 	&sensor_dev_attr_in2_max.dev_attr.attr,
579 	&sensor_dev_attr_in3_max.dev_attr.attr,
580 	&sensor_dev_attr_in4_max.dev_attr.attr,
581 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
582 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
583 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
584 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
585 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
586 
587 	&sensor_dev_attr_temp1_input.dev_attr.attr,
588 	&sensor_dev_attr_temp2_input.dev_attr.attr,
589 	&sensor_dev_attr_temp3_input.dev_attr.attr,
590 	&sensor_dev_attr_temp1_max.dev_attr.attr,
591 	&sensor_dev_attr_temp2_max.dev_attr.attr,
592 	&sensor_dev_attr_temp3_max.dev_attr.attr,
593 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
594 	&sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
595 	&sensor_dev_attr_temp3_max_hyst.dev_attr.attr,
596 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
597 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
598 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
599 
600 	&sensor_dev_attr_fan1_input.dev_attr.attr,
601 	&sensor_dev_attr_fan2_input.dev_attr.attr,
602 	&sensor_dev_attr_fan1_min.dev_attr.attr,
603 	&sensor_dev_attr_fan2_min.dev_attr.attr,
604 	&sensor_dev_attr_fan1_div.dev_attr.attr,
605 	&sensor_dev_attr_fan2_div.dev_attr.attr,
606 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
607 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
608 
609 	&dev_attr_alarms.attr,
610 	&dev_attr_name.attr,
611 	NULL
612 };
613 
614 static const struct attribute_group via686a_group = {
615 	.attrs = via686a_attributes,
616 };
617 
618 static struct platform_driver via686a_driver = {
619 	.driver = {
620 		.owner	= THIS_MODULE,
621 		.name	= "via686a",
622 	},
623 	.probe		= via686a_probe,
624 	.remove		= __devexit_p(via686a_remove),
625 };
626 
627 
628 /* This is called when the module is loaded */
629 static int __devinit via686a_probe(struct platform_device *pdev)
630 {
631 	struct via686a_data *data;
632 	struct resource *res;
633 	int err;
634 
635 	/* Reserve the ISA region */
636 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
637 	if (!request_region(res->start, VIA686A_EXTENT,
638 			    via686a_driver.driver.name)) {
639 		dev_err(&pdev->dev, "Region 0x%lx-0x%lx already in use!\n",
640 			(unsigned long)res->start, (unsigned long)res->end);
641 		return -ENODEV;
642 	}
643 
644 	if (!(data = kzalloc(sizeof(struct via686a_data), GFP_KERNEL))) {
645 		err = -ENOMEM;
646 		goto exit_release;
647 	}
648 
649 	platform_set_drvdata(pdev, data);
650 	data->addr = res->start;
651 	data->name = "via686a";
652 	mutex_init(&data->update_lock);
653 
654 	/* Initialize the VIA686A chip */
655 	via686a_init_device(data);
656 
657 	/* Register sysfs hooks */
658 	if ((err = sysfs_create_group(&pdev->dev.kobj, &via686a_group)))
659 		goto exit_free;
660 
661 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
662 	if (IS_ERR(data->hwmon_dev)) {
663 		err = PTR_ERR(data->hwmon_dev);
664 		goto exit_remove_files;
665 	}
666 
667 	return 0;
668 
669 exit_remove_files:
670 	sysfs_remove_group(&pdev->dev.kobj, &via686a_group);
671 exit_free:
672 	kfree(data);
673 exit_release:
674 	release_region(res->start, VIA686A_EXTENT);
675 	return err;
676 }
677 
678 static int __devexit via686a_remove(struct platform_device *pdev)
679 {
680 	struct via686a_data *data = platform_get_drvdata(pdev);
681 
682 	hwmon_device_unregister(data->hwmon_dev);
683 	sysfs_remove_group(&pdev->dev.kobj, &via686a_group);
684 
685 	release_region(data->addr, VIA686A_EXTENT);
686 	platform_set_drvdata(pdev, NULL);
687 	kfree(data);
688 
689 	return 0;
690 }
691 
692 static void via686a_update_fan_div(struct via686a_data *data)
693 {
694 	int reg = via686a_read_value(data, VIA686A_REG_FANDIV);
695 	data->fan_div[0] = (reg >> 4) & 0x03;
696 	data->fan_div[1] = reg >> 6;
697 }
698 
699 static void __devinit via686a_init_device(struct via686a_data *data)
700 {
701 	u8 reg;
702 
703 	/* Start monitoring */
704 	reg = via686a_read_value(data, VIA686A_REG_CONFIG);
705 	via686a_write_value(data, VIA686A_REG_CONFIG, (reg | 0x01) & 0x7F);
706 
707 	/* Configure temp interrupt mode for continuous-interrupt operation */
708 	reg = via686a_read_value(data, VIA686A_REG_TEMP_MODE);
709 	via686a_write_value(data, VIA686A_REG_TEMP_MODE,
710 			    (reg & ~VIA686A_TEMP_MODE_MASK)
711 			    | VIA686A_TEMP_MODE_CONTINUOUS);
712 
713 	/* Pre-read fan clock divisor values */
714 	via686a_update_fan_div(data);
715 }
716 
717 static struct via686a_data *via686a_update_device(struct device *dev)
718 {
719 	struct via686a_data *data = dev_get_drvdata(dev);
720 	int i;
721 
722 	mutex_lock(&data->update_lock);
723 
724 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
725 	    || !data->valid) {
726 		for (i = 0; i <= 4; i++) {
727 			data->in[i] =
728 			    via686a_read_value(data, VIA686A_REG_IN(i));
729 			data->in_min[i] = via686a_read_value(data,
730 							     VIA686A_REG_IN_MIN
731 							     (i));
732 			data->in_max[i] =
733 			    via686a_read_value(data, VIA686A_REG_IN_MAX(i));
734 		}
735 		for (i = 1; i <= 2; i++) {
736 			data->fan[i - 1] =
737 			    via686a_read_value(data, VIA686A_REG_FAN(i));
738 			data->fan_min[i - 1] = via686a_read_value(data,
739 						     VIA686A_REG_FAN_MIN(i));
740 		}
741 		for (i = 0; i <= 2; i++) {
742 			data->temp[i] = via686a_read_value(data,
743 						 VIA686A_REG_TEMP[i]) << 2;
744 			data->temp_over[i] =
745 			    via686a_read_value(data,
746 					       VIA686A_REG_TEMP_OVER[i]);
747 			data->temp_hyst[i] =
748 			    via686a_read_value(data,
749 					       VIA686A_REG_TEMP_HYST[i]);
750 		}
751 		/* add in lower 2 bits
752 		   temp1 uses bits 7-6 of VIA686A_REG_TEMP_LOW1
753 		   temp2 uses bits 5-4 of VIA686A_REG_TEMP_LOW23
754 		   temp3 uses bits 7-6 of VIA686A_REG_TEMP_LOW23
755 		 */
756 		data->temp[0] |= (via686a_read_value(data,
757 						     VIA686A_REG_TEMP_LOW1)
758 				  & 0xc0) >> 6;
759 		data->temp[1] |=
760 		    (via686a_read_value(data, VIA686A_REG_TEMP_LOW23) &
761 		     0x30) >> 4;
762 		data->temp[2] |=
763 		    (via686a_read_value(data, VIA686A_REG_TEMP_LOW23) &
764 		     0xc0) >> 6;
765 
766 		via686a_update_fan_div(data);
767 		data->alarms =
768 		    via686a_read_value(data,
769 				       VIA686A_REG_ALARM1) |
770 		    (via686a_read_value(data, VIA686A_REG_ALARM2) << 8);
771 		data->last_updated = jiffies;
772 		data->valid = 1;
773 	}
774 
775 	mutex_unlock(&data->update_lock);
776 
777 	return data;
778 }
779 
780 static const struct pci_device_id via686a_pci_ids[] = {
781 	{ PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686_4) },
782 	{ 0, }
783 };
784 
785 MODULE_DEVICE_TABLE(pci, via686a_pci_ids);
786 
787 static int __devinit via686a_device_add(unsigned short address)
788 {
789 	struct resource res = {
790 		.start	= address,
791 		.end	= address + VIA686A_EXTENT - 1,
792 		.name	= "via686a",
793 		.flags	= IORESOURCE_IO,
794 	};
795 	int err;
796 
797 	err = acpi_check_resource_conflict(&res);
798 	if (err)
799 		goto exit;
800 
801 	pdev = platform_device_alloc("via686a", address);
802 	if (!pdev) {
803 		err = -ENOMEM;
804 		pr_err("Device allocation failed\n");
805 		goto exit;
806 	}
807 
808 	err = platform_device_add_resources(pdev, &res, 1);
809 	if (err) {
810 		pr_err("Device resource addition failed (%d)\n", err);
811 		goto exit_device_put;
812 	}
813 
814 	err = platform_device_add(pdev);
815 	if (err) {
816 		pr_err("Device addition failed (%d)\n", err);
817 		goto exit_device_put;
818 	}
819 
820 	return 0;
821 
822 exit_device_put:
823 	platform_device_put(pdev);
824 exit:
825 	return err;
826 }
827 
828 static int __devinit via686a_pci_probe(struct pci_dev *dev,
829 				       const struct pci_device_id *id)
830 {
831 	u16 address, val;
832 
833 	if (force_addr) {
834 		address = force_addr & ~(VIA686A_EXTENT - 1);
835 		dev_warn(&dev->dev, "Forcing ISA address 0x%x\n", address);
836 		if (PCIBIOS_SUCCESSFUL !=
837 		    pci_write_config_word(dev, VIA686A_BASE_REG, address | 1))
838 			return -ENODEV;
839 	}
840 	if (PCIBIOS_SUCCESSFUL !=
841 	    pci_read_config_word(dev, VIA686A_BASE_REG, &val))
842 		return -ENODEV;
843 
844 	address = val & ~(VIA686A_EXTENT - 1);
845 	if (address == 0) {
846 		dev_err(&dev->dev, "base address not set - upgrade BIOS "
847 			"or use force_addr=0xaddr\n");
848 		return -ENODEV;
849 	}
850 
851 	if (PCIBIOS_SUCCESSFUL !=
852 	    pci_read_config_word(dev, VIA686A_ENABLE_REG, &val))
853 		return -ENODEV;
854 	if (!(val & 0x0001)) {
855 		if (!force_addr) {
856 			dev_warn(&dev->dev, "Sensors disabled, enable "
857 				 "with force_addr=0x%x\n", address);
858 			return -ENODEV;
859 		}
860 
861 		dev_warn(&dev->dev, "Enabling sensors\n");
862 		if (PCIBIOS_SUCCESSFUL !=
863 		    pci_write_config_word(dev, VIA686A_ENABLE_REG,
864 					  val | 0x0001))
865 			return -ENODEV;
866 	}
867 
868 	if (platform_driver_register(&via686a_driver))
869 		goto exit;
870 
871 	/* Sets global pdev as a side effect */
872 	if (via686a_device_add(address))
873 		goto exit_unregister;
874 
875 	/* Always return failure here.  This is to allow other drivers to bind
876 	 * to this pci device.  We don't really want to have control over the
877 	 * pci device, we only wanted to read as few register values from it.
878 	 */
879 	s_bridge = pci_dev_get(dev);
880 	return -ENODEV;
881 
882 exit_unregister:
883 	platform_driver_unregister(&via686a_driver);
884 exit:
885 	return -ENODEV;
886 }
887 
888 static struct pci_driver via686a_pci_driver = {
889 	.name		= "via686a",
890 	.id_table	= via686a_pci_ids,
891 	.probe		= via686a_pci_probe,
892 };
893 
894 static int __init sm_via686a_init(void)
895 {
896 	return pci_register_driver(&via686a_pci_driver);
897 }
898 
899 static void __exit sm_via686a_exit(void)
900 {
901 	pci_unregister_driver(&via686a_pci_driver);
902 	if (s_bridge != NULL) {
903 		platform_device_unregister(pdev);
904 		platform_driver_unregister(&via686a_driver);
905 		pci_dev_put(s_bridge);
906 		s_bridge = NULL;
907 	}
908 }
909 
910 MODULE_AUTHOR("Kyösti Mälkki <kmalkki@cc.hut.fi>, "
911 	      "Mark Studebaker <mdsxyz123@yahoo.com> "
912 	      "and Bob Dougherty <bobd@stanford.edu>");
913 MODULE_DESCRIPTION("VIA 686A Sensor device");
914 MODULE_LICENSE("GPL");
915 
916 module_init(sm_via686a_init);
917 module_exit(sm_via686a_exit);
918