xref: /openbmc/linux/drivers/hwmon/via686a.c (revision a325f174)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * via686a.c - Part of lm_sensors, Linux kernel modules
4  *	       for hardware monitoring
5  *
6  * Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
7  *			      Kyösti Mälkki <kmalkki@cc.hut.fi>,
8  *			      Mark Studebaker <mdsxyz123@yahoo.com>,
9  *			      and Bob Dougherty <bobd@stanford.edu>
10  *
11  * (Some conversion-factor data were contributed by Jonathan Teh Soon Yew
12  * <j.teh@iname.com> and Alex van Kaam <darkside@chello.nl>.)
13  */
14 
15 /*
16  * Supports the Via VT82C686A, VT82C686B south bridges.
17  * Reports all as a 686A.
18  * Warning - only supports a single device.
19  */
20 
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 
23 #include <linux/module.h>
24 #include <linux/slab.h>
25 #include <linux/pci.h>
26 #include <linux/jiffies.h>
27 #include <linux/platform_device.h>
28 #include <linux/hwmon.h>
29 #include <linux/hwmon-sysfs.h>
30 #include <linux/err.h>
31 #include <linux/init.h>
32 #include <linux/mutex.h>
33 #include <linux/sysfs.h>
34 #include <linux/acpi.h>
35 #include <linux/io.h>
36 
37 #define DRIVER_NAME "via686a"
38 
39 /*
40  * If force_addr is set to anything different from 0, we forcibly enable
41  * the device at the given address.
42  */
43 static unsigned short force_addr;
44 module_param(force_addr, ushort, 0);
45 MODULE_PARM_DESC(force_addr,
46 		 "Initialize the base address of the sensors");
47 
48 static struct platform_device *pdev;
49 
50 /*
51  * The Via 686a southbridge has a LM78-like chip integrated on the same IC.
52  * This driver is a customized copy of lm78.c
53  */
54 
55 /* Many VIA686A constants specified below */
56 
57 /* Length of ISA address segment */
58 #define VIA686A_EXTENT		0x80
59 #define VIA686A_BASE_REG	0x70
60 #define VIA686A_ENABLE_REG	0x74
61 
62 /* The VIA686A registers */
63 /* ins numbered 0-4 */
64 #define VIA686A_REG_IN_MAX(nr)	(0x2b + ((nr) * 2))
65 #define VIA686A_REG_IN_MIN(nr)	(0x2c + ((nr) * 2))
66 #define VIA686A_REG_IN(nr)	(0x22 + (nr))
67 
68 /* fans numbered 1-2 */
69 #define VIA686A_REG_FAN_MIN(nr)	(0x3a + (nr))
70 #define VIA686A_REG_FAN(nr)	(0x28 + (nr))
71 
72 /* temps numbered 1-3 */
73 static const u8 VIA686A_REG_TEMP[]	= { 0x20, 0x21, 0x1f };
74 static const u8 VIA686A_REG_TEMP_OVER[]	= { 0x39, 0x3d, 0x1d };
75 static const u8 VIA686A_REG_TEMP_HYST[]	= { 0x3a, 0x3e, 0x1e };
76 /* bits 7-6 */
77 #define VIA686A_REG_TEMP_LOW1	0x4b
78 /* 2 = bits 5-4, 3 = bits 7-6 */
79 #define VIA686A_REG_TEMP_LOW23	0x49
80 
81 #define VIA686A_REG_ALARM1	0x41
82 #define VIA686A_REG_ALARM2	0x42
83 #define VIA686A_REG_FANDIV	0x47
84 #define VIA686A_REG_CONFIG	0x40
85 /*
86  * The following register sets temp interrupt mode (bits 1-0 for temp1,
87  * 3-2 for temp2, 5-4 for temp3).  Modes are:
88  * 00 interrupt stays as long as value is out-of-range
89  * 01 interrupt is cleared once register is read (default)
90  * 10 comparator mode- like 00, but ignores hysteresis
91  * 11 same as 00
92  */
93 #define VIA686A_REG_TEMP_MODE		0x4b
94 /* We'll just assume that you want to set all 3 simultaneously: */
95 #define VIA686A_TEMP_MODE_MASK		0x3F
96 #define VIA686A_TEMP_MODE_CONTINUOUS	0x00
97 
98 /*
99  * Conversions. Limit checking is only done on the TO_REG
100  * variants.
101  *
102  ******** VOLTAGE CONVERSIONS (Bob Dougherty) ********
103  * From HWMon.cpp (Copyright 1998-2000 Jonathan Teh Soon Yew):
104  * voltagefactor[0]=1.25/2628; (2628/1.25=2102.4)   // Vccp
105  * voltagefactor[1]=1.25/2628; (2628/1.25=2102.4)   // +2.5V
106  * voltagefactor[2]=1.67/2628; (2628/1.67=1573.7)   // +3.3V
107  * voltagefactor[3]=2.6/2628;  (2628/2.60=1010.8)   // +5V
108  * voltagefactor[4]=6.3/2628;  (2628/6.30=417.14)   // +12V
109  * in[i]=(data[i+2]*25.0+133)*voltagefactor[i];
110  * That is:
111  * volts = (25*regVal+133)*factor
112  * regVal = (volts/factor-133)/25
113  * (These conversions were contributed by Jonathan Teh Soon Yew
114  * <j.teh@iname.com>)
115  */
116 static inline u8 IN_TO_REG(long val, int in_num)
117 {
118 	/*
119 	 * To avoid floating point, we multiply constants by 10 (100 for +12V).
120 	 * Rounding is done (120500 is actually 133000 - 12500).
121 	 * Remember that val is expressed in 0.001V/bit, which is why we divide
122 	 * by an additional 10000 (100000 for +12V): 1000 for val and 10 (100)
123 	 * for the constants.
124 	 */
125 	if (in_num <= 1)
126 		return (u8) clamp_val((val * 21024 - 1205000) / 250000, 0, 255);
127 	else if (in_num == 2)
128 		return (u8) clamp_val((val * 15737 - 1205000) / 250000, 0, 255);
129 	else if (in_num == 3)
130 		return (u8) clamp_val((val * 10108 - 1205000) / 250000, 0, 255);
131 	else
132 		return (u8) clamp_val((val * 41714 - 12050000) / 2500000, 0,
133 				      255);
134 }
135 
136 static inline long IN_FROM_REG(u8 val, int in_num)
137 {
138 	/*
139 	 * To avoid floating point, we multiply constants by 10 (100 for +12V).
140 	 * We also multiply them by 1000 because we want 0.001V/bit for the
141 	 * output value. Rounding is done.
142 	 */
143 	if (in_num <= 1)
144 		return (long) ((250000 * val + 1330000 + 21024 / 2) / 21024);
145 	else if (in_num == 2)
146 		return (long) ((250000 * val + 1330000 + 15737 / 2) / 15737);
147 	else if (in_num == 3)
148 		return (long) ((250000 * val + 1330000 + 10108 / 2) / 10108);
149 	else
150 		return (long) ((2500000 * val + 13300000 + 41714 / 2) / 41714);
151 }
152 
153 /********* FAN RPM CONVERSIONS ********/
154 /*
155  * Higher register values = slower fans (the fan's strobe gates a counter).
156  * But this chip saturates back at 0, not at 255 like all the other chips.
157  * So, 0 means 0 RPM
158  */
159 static inline u8 FAN_TO_REG(long rpm, int div)
160 {
161 	if (rpm == 0)
162 		return 0;
163 	rpm = clamp_val(rpm, 1, 1000000);
164 	return clamp_val((1350000 + rpm * div / 2) / (rpm * div), 1, 255);
165 }
166 
167 #define FAN_FROM_REG(val, div) ((val) == 0 ? 0 : (val) == 255 ? 0 : 1350000 / \
168 				((val) * (div)))
169 
170 /******** TEMP CONVERSIONS (Bob Dougherty) *********/
171 /*
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, temp_lut
202  * is the temp at via register values 0-255:
203  */
204 static const s16 temp_lut[] = {
205 	-709, -688, -667, -646, -627, -607, -589, -570, -553, -536, -519,
206 	-503, -487, -471, -456, -442, -428, -414, -400, -387, -375,
207 	-362, -350, -339, -327, -316, -305, -295, -285, -275, -265,
208 	-255, -246, -237, -229, -220, -212, -204, -196, -188, -180,
209 	-173, -166, -159, -152, -145, -139, -132, -126, -120, -114,
210 	-108, -102, -96, -91, -85, -80, -74, -69, -64, -59, -54, -49,
211 	-44, -39, -34, -29, -25, -20, -15, -11, -6, -2, 3, 7, 12, 16,
212 	20, 25, 29, 33, 37, 42, 46, 50, 54, 59, 63, 67, 71, 75, 79, 84,
213 	88, 92, 96, 100, 104, 109, 113, 117, 121, 125, 130, 134, 138,
214 	142, 146, 151, 155, 159, 163, 168, 172, 176, 181, 185, 189,
215 	193, 198, 202, 206, 211, 215, 219, 224, 228, 232, 237, 241,
216 	245, 250, 254, 259, 263, 267, 272, 276, 281, 285, 290, 294,
217 	299, 303, 307, 312, 316, 321, 325, 330, 334, 339, 344, 348,
218 	353, 357, 362, 366, 371, 376, 380, 385, 390, 395, 399, 404,
219 	409, 414, 419, 423, 428, 433, 438, 443, 449, 454, 459, 464,
220 	469, 475, 480, 486, 491, 497, 502, 508, 514, 520, 526, 532,
221 	538, 544, 551, 557, 564, 571, 578, 584, 592, 599, 606, 614,
222 	621, 629, 637, 645, 654, 662, 671, 680, 689, 698, 708, 718,
223 	728, 738, 749, 759, 770, 782, 793, 805, 818, 830, 843, 856,
224 	870, 883, 898, 912, 927, 943, 958, 975, 991, 1008, 1026, 1044,
225 	1062, 1081, 1101, 1121, 1141, 1162, 1184, 1206, 1229, 1252,
226 	1276, 1301, 1326, 1352, 1378, 1406, 1434, 1462
227 };
228 
229 /*
230  * the original LUT values from Alex van Kaam <darkside@chello.nl>
231  * (for via register values 12-240):
232  * {-50,-49,-47,-45,-43,-41,-39,-38,-37,-35,-34,-33,-32,-31,
233  * -30,-29,-28,-27,-26,-25,-24,-24,-23,-22,-21,-20,-20,-19,-18,-17,-17,-16,-15,
234  * -15,-14,-14,-13,-12,-12,-11,-11,-10,-9,-9,-8,-8,-7,-7,-6,-6,-5,-5,-4,-4,-3,
235  * -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,
236  * 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,
237  * 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,
238  * 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,
239  * 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,
240  * 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,
241  * 85,86,88,89,91,92,94,96,97,99,101,103,105,107,109,110};
242  *
243  *
244  * Here's the reverse LUT.  I got it by doing a 6-th order poly fit (needed
245  * an extra term for a good fit to these inverse data!) and then
246  * solving for each temp value from -50 to 110 (the useable range for
247  * this chip).  Here's the fit:
248  * viaRegVal = -1.160370e-10*val^6 +3.193693e-08*val^5 - 1.464447e-06*val^4
249  * - 2.525453e-04*val^3 + 1.424593e-02*val^2 + 2.148941e+00*val +7.275808e+01)
250  * Note that n=161:
251  */
252 static const u8 via_lut[] = {
253 	12, 12, 13, 14, 14, 15, 16, 16, 17, 18, 18, 19, 20, 20, 21, 22, 23,
254 	23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 35, 36, 37, 39, 40,
255 	41, 43, 45, 46, 48, 49, 51, 53, 55, 57, 59, 60, 62, 64, 66,
256 	69, 71, 73, 75, 77, 79, 82, 84, 86, 88, 91, 93, 95, 98, 100,
257 	103, 105, 107, 110, 112, 115, 117, 119, 122, 124, 126, 129,
258 	131, 134, 136, 138, 140, 143, 145, 147, 150, 152, 154, 156,
259 	158, 160, 162, 164, 166, 168, 170, 172, 174, 176, 178, 180,
260 	182, 183, 185, 187, 188, 190, 192, 193, 195, 196, 198, 199,
261 	200, 202, 203, 205, 206, 207, 208, 209, 210, 211, 212, 213,
262 	214, 215, 216, 217, 218, 219, 220, 221, 222, 222, 223, 224,
263 	225, 226, 226, 227, 228, 228, 229, 230, 230, 231, 232, 232,
264 	233, 233, 234, 235, 235, 236, 236, 237, 237, 238, 238, 239,
265 	239, 240
266 };
267 
268 /*
269  * Converting temps to (8-bit) hyst and over registers
270  * No interpolation here.
271  * The +50 is because the temps start at -50
272  */
273 static inline u8 TEMP_TO_REG(long val)
274 {
275 	return via_lut[val <= -50000 ? 0 : val >= 110000 ? 160 :
276 		      (val < 0 ? val - 500 : val + 500) / 1000 + 50];
277 }
278 
279 /* for 8-bit temperature hyst and over registers */
280 #define TEMP_FROM_REG(val)	((long)temp_lut[val] * 100)
281 
282 /* for 10-bit temperature readings */
283 static inline long TEMP_FROM_REG10(u16 val)
284 {
285 	u16 eight_bits = val >> 2;
286 	u16 two_bits = val & 3;
287 
288 	/* no interpolation for these */
289 	if (two_bits == 0 || eight_bits == 255)
290 		return TEMP_FROM_REG(eight_bits);
291 
292 	/* do some linear interpolation */
293 	return (temp_lut[eight_bits] * (4 - two_bits) +
294 		temp_lut[eight_bits + 1] * two_bits) * 25;
295 }
296 
297 #define DIV_FROM_REG(val) (1 << (val))
298 #define DIV_TO_REG(val) ((val) == 8 ? 3 : (val) == 4 ? 2 : (val) == 1 ? 0 : 1)
299 
300 /*
301  * For each registered chip, we need to keep some data in memory.
302  * The structure is dynamically allocated.
303  */
304 struct via686a_data {
305 	unsigned short addr;
306 	const char *name;
307 	struct device *hwmon_dev;
308 	struct mutex update_lock;
309 	bool valid;		/* true if following fields are valid */
310 	unsigned long last_updated;	/* In jiffies */
311 
312 	u8 in[5];		/* Register value */
313 	u8 in_max[5];		/* Register value */
314 	u8 in_min[5];		/* Register value */
315 	u8 fan[2];		/* Register value */
316 	u8 fan_min[2];		/* Register value */
317 	u16 temp[3];		/* Register value 10 bit */
318 	u8 temp_over[3];	/* Register value */
319 	u8 temp_hyst[3];	/* Register value */
320 	u8 fan_div[2];		/* Register encoding, shifted right */
321 	u16 alarms;		/* Register encoding, combined */
322 };
323 
324 static struct pci_dev *s_bridge;	/* pointer to the (only) via686a */
325 
326 static inline int via686a_read_value(struct via686a_data *data, u8 reg)
327 {
328 	return inb_p(data->addr + reg);
329 }
330 
331 static inline void via686a_write_value(struct via686a_data *data, u8 reg,
332 				       u8 value)
333 {
334 	outb_p(value, data->addr + reg);
335 }
336 
337 static void via686a_update_fan_div(struct via686a_data *data)
338 {
339 	int reg = via686a_read_value(data, VIA686A_REG_FANDIV);
340 	data->fan_div[0] = (reg >> 4) & 0x03;
341 	data->fan_div[1] = reg >> 6;
342 }
343 
344 static struct via686a_data *via686a_update_device(struct device *dev)
345 {
346 	struct via686a_data *data = dev_get_drvdata(dev);
347 	int i;
348 
349 	mutex_lock(&data->update_lock);
350 
351 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
352 	    || !data->valid) {
353 		for (i = 0; i <= 4; i++) {
354 			data->in[i] =
355 			    via686a_read_value(data, VIA686A_REG_IN(i));
356 			data->in_min[i] = via686a_read_value(data,
357 							     VIA686A_REG_IN_MIN
358 							     (i));
359 			data->in_max[i] =
360 			    via686a_read_value(data, VIA686A_REG_IN_MAX(i));
361 		}
362 		for (i = 1; i <= 2; i++) {
363 			data->fan[i - 1] =
364 			    via686a_read_value(data, VIA686A_REG_FAN(i));
365 			data->fan_min[i - 1] = via686a_read_value(data,
366 						     VIA686A_REG_FAN_MIN(i));
367 		}
368 		for (i = 0; i <= 2; i++) {
369 			data->temp[i] = via686a_read_value(data,
370 						 VIA686A_REG_TEMP[i]) << 2;
371 			data->temp_over[i] =
372 			    via686a_read_value(data,
373 					       VIA686A_REG_TEMP_OVER[i]);
374 			data->temp_hyst[i] =
375 			    via686a_read_value(data,
376 					       VIA686A_REG_TEMP_HYST[i]);
377 		}
378 		/*
379 		 * add in lower 2 bits
380 		 * temp1 uses bits 7-6 of VIA686A_REG_TEMP_LOW1
381 		 * temp2 uses bits 5-4 of VIA686A_REG_TEMP_LOW23
382 		 * temp3 uses bits 7-6 of VIA686A_REG_TEMP_LOW23
383 		 */
384 		data->temp[0] |= (via686a_read_value(data,
385 						     VIA686A_REG_TEMP_LOW1)
386 				  & 0xc0) >> 6;
387 		data->temp[1] |=
388 		    (via686a_read_value(data, VIA686A_REG_TEMP_LOW23) &
389 		     0x30) >> 4;
390 		data->temp[2] |=
391 		    (via686a_read_value(data, VIA686A_REG_TEMP_LOW23) &
392 		     0xc0) >> 6;
393 
394 		via686a_update_fan_div(data);
395 		data->alarms =
396 		    via686a_read_value(data,
397 				       VIA686A_REG_ALARM1) |
398 		    (via686a_read_value(data, VIA686A_REG_ALARM2) << 8);
399 		data->last_updated = jiffies;
400 		data->valid = true;
401 	}
402 
403 	mutex_unlock(&data->update_lock);
404 
405 	return data;
406 }
407 
408 /* following are the sysfs callback functions */
409 
410 /* 7 voltage sensors */
411 static ssize_t in_show(struct device *dev, struct device_attribute *da,
412 		       char *buf) {
413 	struct via686a_data *data = via686a_update_device(dev);
414 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
415 	int nr = attr->index;
416 	return sprintf(buf, "%ld\n", IN_FROM_REG(data->in[nr], nr));
417 }
418 
419 static ssize_t in_min_show(struct device *dev, struct device_attribute *da,
420 			   char *buf) {
421 	struct via686a_data *data = via686a_update_device(dev);
422 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
423 	int nr = attr->index;
424 	return sprintf(buf, "%ld\n", IN_FROM_REG(data->in_min[nr], nr));
425 }
426 
427 static ssize_t in_max_show(struct device *dev, struct device_attribute *da,
428 			   char *buf) {
429 	struct via686a_data *data = via686a_update_device(dev);
430 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
431 	int nr = attr->index;
432 	return sprintf(buf, "%ld\n", IN_FROM_REG(data->in_max[nr], nr));
433 }
434 
435 static ssize_t in_min_store(struct device *dev, struct device_attribute *da,
436 			    const char *buf, size_t count) {
437 	struct via686a_data *data = dev_get_drvdata(dev);
438 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
439 	int nr = attr->index;
440 	unsigned long val;
441 	int err;
442 
443 	err = kstrtoul(buf, 10, &val);
444 	if (err)
445 		return err;
446 
447 	mutex_lock(&data->update_lock);
448 	data->in_min[nr] = IN_TO_REG(val, nr);
449 	via686a_write_value(data, VIA686A_REG_IN_MIN(nr),
450 			data->in_min[nr]);
451 	mutex_unlock(&data->update_lock);
452 	return count;
453 }
454 static ssize_t in_max_store(struct device *dev, struct device_attribute *da,
455 			    const char *buf, size_t count) {
456 	struct via686a_data *data = dev_get_drvdata(dev);
457 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
458 	int nr = attr->index;
459 	unsigned long val;
460 	int err;
461 
462 	err = kstrtoul(buf, 10, &val);
463 	if (err)
464 		return err;
465 
466 	mutex_lock(&data->update_lock);
467 	data->in_max[nr] = IN_TO_REG(val, nr);
468 	via686a_write_value(data, VIA686A_REG_IN_MAX(nr),
469 			data->in_max[nr]);
470 	mutex_unlock(&data->update_lock);
471 	return count;
472 }
473 
474 static SENSOR_DEVICE_ATTR_RO(in0_input, in, 0);
475 static SENSOR_DEVICE_ATTR_RW(in0_min, in_min, 0);
476 static SENSOR_DEVICE_ATTR_RW(in0_max, in_max, 0);
477 static SENSOR_DEVICE_ATTR_RO(in1_input, in, 1);
478 static SENSOR_DEVICE_ATTR_RW(in1_min, in_min, 1);
479 static SENSOR_DEVICE_ATTR_RW(in1_max, in_max, 1);
480 static SENSOR_DEVICE_ATTR_RO(in2_input, in, 2);
481 static SENSOR_DEVICE_ATTR_RW(in2_min, in_min, 2);
482 static SENSOR_DEVICE_ATTR_RW(in2_max, in_max, 2);
483 static SENSOR_DEVICE_ATTR_RO(in3_input, in, 3);
484 static SENSOR_DEVICE_ATTR_RW(in3_min, in_min, 3);
485 static SENSOR_DEVICE_ATTR_RW(in3_max, in_max, 3);
486 static SENSOR_DEVICE_ATTR_RO(in4_input, in, 4);
487 static SENSOR_DEVICE_ATTR_RW(in4_min, in_min, 4);
488 static SENSOR_DEVICE_ATTR_RW(in4_max, in_max, 4);
489 
490 /* 3 temperatures */
491 static ssize_t temp_show(struct device *dev, struct device_attribute *da,
492 			 char *buf) {
493 	struct via686a_data *data = via686a_update_device(dev);
494 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
495 	int nr = attr->index;
496 	return sprintf(buf, "%ld\n", TEMP_FROM_REG10(data->temp[nr]));
497 }
498 static ssize_t temp_over_show(struct device *dev, struct device_attribute *da,
499 			      char *buf) {
500 	struct via686a_data *data = via686a_update_device(dev);
501 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
502 	int nr = attr->index;
503 	return sprintf(buf, "%ld\n", TEMP_FROM_REG(data->temp_over[nr]));
504 }
505 static ssize_t temp_hyst_show(struct device *dev, struct device_attribute *da,
506 			      char *buf) {
507 	struct via686a_data *data = via686a_update_device(dev);
508 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
509 	int nr = attr->index;
510 	return sprintf(buf, "%ld\n", TEMP_FROM_REG(data->temp_hyst[nr]));
511 }
512 static ssize_t temp_over_store(struct device *dev,
513 			       struct device_attribute *da, const char *buf,
514 			       size_t count) {
515 	struct via686a_data *data = dev_get_drvdata(dev);
516 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
517 	int nr = attr->index;
518 	long val;
519 	int err;
520 
521 	err = kstrtol(buf, 10, &val);
522 	if (err)
523 		return err;
524 
525 	mutex_lock(&data->update_lock);
526 	data->temp_over[nr] = TEMP_TO_REG(val);
527 	via686a_write_value(data, VIA686A_REG_TEMP_OVER[nr],
528 			    data->temp_over[nr]);
529 	mutex_unlock(&data->update_lock);
530 	return count;
531 }
532 static ssize_t temp_hyst_store(struct device *dev,
533 			       struct device_attribute *da, const char *buf,
534 			       size_t count) {
535 	struct via686a_data *data = dev_get_drvdata(dev);
536 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
537 	int nr = attr->index;
538 	long val;
539 	int err;
540 
541 	err = kstrtol(buf, 10, &val);
542 	if (err)
543 		return err;
544 
545 	mutex_lock(&data->update_lock);
546 	data->temp_hyst[nr] = TEMP_TO_REG(val);
547 	via686a_write_value(data, VIA686A_REG_TEMP_HYST[nr],
548 			    data->temp_hyst[nr]);
549 	mutex_unlock(&data->update_lock);
550 	return count;
551 }
552 
553 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
554 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_over, 0);
555 static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, temp_hyst, 0);
556 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp, 1);
557 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_over, 1);
558 static SENSOR_DEVICE_ATTR_RW(temp2_max_hyst, temp_hyst, 1);
559 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp, 2);
560 static SENSOR_DEVICE_ATTR_RW(temp3_max, temp_over, 2);
561 static SENSOR_DEVICE_ATTR_RW(temp3_max_hyst, temp_hyst, 2);
562 
563 /* 2 Fans */
564 static ssize_t fan_show(struct device *dev, struct device_attribute *da,
565 			char *buf) {
566 	struct via686a_data *data = via686a_update_device(dev);
567 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
568 	int nr = attr->index;
569 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
570 				DIV_FROM_REG(data->fan_div[nr])));
571 }
572 static ssize_t fan_min_show(struct device *dev, struct device_attribute *da,
573 			    char *buf) {
574 	struct via686a_data *data = via686a_update_device(dev);
575 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
576 	int nr = attr->index;
577 	return sprintf(buf, "%d\n",
578 		FAN_FROM_REG(data->fan_min[nr],
579 			     DIV_FROM_REG(data->fan_div[nr])));
580 }
581 static ssize_t fan_div_show(struct device *dev, struct device_attribute *da,
582 			    char *buf) {
583 	struct via686a_data *data = via686a_update_device(dev);
584 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
585 	int nr = attr->index;
586 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
587 }
588 static ssize_t fan_min_store(struct device *dev, struct device_attribute *da,
589 			     const char *buf, size_t count) {
590 	struct via686a_data *data = dev_get_drvdata(dev);
591 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
592 	int nr = attr->index;
593 	unsigned long val;
594 	int err;
595 
596 	err = kstrtoul(buf, 10, &val);
597 	if (err)
598 		return err;
599 
600 	mutex_lock(&data->update_lock);
601 	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
602 	via686a_write_value(data, VIA686A_REG_FAN_MIN(nr+1), data->fan_min[nr]);
603 	mutex_unlock(&data->update_lock);
604 	return count;
605 }
606 static ssize_t fan_div_store(struct device *dev, struct device_attribute *da,
607 			     const char *buf, size_t count) {
608 	struct via686a_data *data = dev_get_drvdata(dev);
609 	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
610 	int nr = attr->index;
611 	int old;
612 	unsigned long val;
613 	int err;
614 
615 	err = kstrtoul(buf, 10, &val);
616 	if (err)
617 		return err;
618 
619 	mutex_lock(&data->update_lock);
620 	old = via686a_read_value(data, VIA686A_REG_FANDIV);
621 	data->fan_div[nr] = DIV_TO_REG(val);
622 	old = (old & 0x0f) | (data->fan_div[1] << 6) | (data->fan_div[0] << 4);
623 	via686a_write_value(data, VIA686A_REG_FANDIV, old);
624 	mutex_unlock(&data->update_lock);
625 	return count;
626 }
627 
628 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0);
629 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
630 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
631 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1);
632 static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
633 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
634 
635 /* Alarms */
636 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
637 			   char *buf)
638 {
639 	struct via686a_data *data = via686a_update_device(dev);
640 	return sprintf(buf, "%u\n", data->alarms);
641 }
642 
643 static DEVICE_ATTR_RO(alarms);
644 
645 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
646 			  char *buf)
647 {
648 	int bitnr = to_sensor_dev_attr(attr)->index;
649 	struct via686a_data *data = via686a_update_device(dev);
650 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
651 }
652 static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0);
653 static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 1);
654 static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 2);
655 static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 3);
656 static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 8);
657 static SENSOR_DEVICE_ATTR_RO(temp1_alarm, alarm, 4);
658 static SENSOR_DEVICE_ATTR_RO(temp2_alarm, alarm, 11);
659 static SENSOR_DEVICE_ATTR_RO(temp3_alarm, alarm, 15);
660 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, alarm, 6);
661 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, alarm, 7);
662 
663 static ssize_t name_show(struct device *dev, struct device_attribute
664 			 *devattr, char *buf)
665 {
666 	struct via686a_data *data = dev_get_drvdata(dev);
667 	return sprintf(buf, "%s\n", data->name);
668 }
669 static DEVICE_ATTR_RO(name);
670 
671 static struct attribute *via686a_attributes[] = {
672 	&sensor_dev_attr_in0_input.dev_attr.attr,
673 	&sensor_dev_attr_in1_input.dev_attr.attr,
674 	&sensor_dev_attr_in2_input.dev_attr.attr,
675 	&sensor_dev_attr_in3_input.dev_attr.attr,
676 	&sensor_dev_attr_in4_input.dev_attr.attr,
677 	&sensor_dev_attr_in0_min.dev_attr.attr,
678 	&sensor_dev_attr_in1_min.dev_attr.attr,
679 	&sensor_dev_attr_in2_min.dev_attr.attr,
680 	&sensor_dev_attr_in3_min.dev_attr.attr,
681 	&sensor_dev_attr_in4_min.dev_attr.attr,
682 	&sensor_dev_attr_in0_max.dev_attr.attr,
683 	&sensor_dev_attr_in1_max.dev_attr.attr,
684 	&sensor_dev_attr_in2_max.dev_attr.attr,
685 	&sensor_dev_attr_in3_max.dev_attr.attr,
686 	&sensor_dev_attr_in4_max.dev_attr.attr,
687 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
688 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
689 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
690 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
691 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
692 
693 	&sensor_dev_attr_temp1_input.dev_attr.attr,
694 	&sensor_dev_attr_temp2_input.dev_attr.attr,
695 	&sensor_dev_attr_temp3_input.dev_attr.attr,
696 	&sensor_dev_attr_temp1_max.dev_attr.attr,
697 	&sensor_dev_attr_temp2_max.dev_attr.attr,
698 	&sensor_dev_attr_temp3_max.dev_attr.attr,
699 	&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
700 	&sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
701 	&sensor_dev_attr_temp3_max_hyst.dev_attr.attr,
702 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
703 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
704 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
705 
706 	&sensor_dev_attr_fan1_input.dev_attr.attr,
707 	&sensor_dev_attr_fan2_input.dev_attr.attr,
708 	&sensor_dev_attr_fan1_min.dev_attr.attr,
709 	&sensor_dev_attr_fan2_min.dev_attr.attr,
710 	&sensor_dev_attr_fan1_div.dev_attr.attr,
711 	&sensor_dev_attr_fan2_div.dev_attr.attr,
712 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
713 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
714 
715 	&dev_attr_alarms.attr,
716 	&dev_attr_name.attr,
717 	NULL
718 };
719 
720 static const struct attribute_group via686a_group = {
721 	.attrs = via686a_attributes,
722 };
723 
724 static void via686a_init_device(struct via686a_data *data)
725 {
726 	u8 reg;
727 
728 	/* Start monitoring */
729 	reg = via686a_read_value(data, VIA686A_REG_CONFIG);
730 	via686a_write_value(data, VIA686A_REG_CONFIG, (reg | 0x01) & 0x7F);
731 
732 	/* Configure temp interrupt mode for continuous-interrupt operation */
733 	reg = via686a_read_value(data, VIA686A_REG_TEMP_MODE);
734 	via686a_write_value(data, VIA686A_REG_TEMP_MODE,
735 			    (reg & ~VIA686A_TEMP_MODE_MASK)
736 			    | VIA686A_TEMP_MODE_CONTINUOUS);
737 
738 	/* Pre-read fan clock divisor values */
739 	via686a_update_fan_div(data);
740 }
741 
742 /* This is called when the module is loaded */
743 static int via686a_probe(struct platform_device *pdev)
744 {
745 	struct via686a_data *data;
746 	struct resource *res;
747 	int err;
748 
749 	/* Reserve the ISA region */
750 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
751 	if (!devm_request_region(&pdev->dev, res->start, VIA686A_EXTENT,
752 				 DRIVER_NAME)) {
753 		dev_err(&pdev->dev, "Region 0x%lx-0x%lx already in use!\n",
754 			(unsigned long)res->start, (unsigned long)res->end);
755 		return -ENODEV;
756 	}
757 
758 	data = devm_kzalloc(&pdev->dev, sizeof(struct via686a_data),
759 			    GFP_KERNEL);
760 	if (!data)
761 		return -ENOMEM;
762 
763 	platform_set_drvdata(pdev, data);
764 	data->addr = res->start;
765 	data->name = DRIVER_NAME;
766 	mutex_init(&data->update_lock);
767 
768 	/* Initialize the VIA686A chip */
769 	via686a_init_device(data);
770 
771 	/* Register sysfs hooks */
772 	err = sysfs_create_group(&pdev->dev.kobj, &via686a_group);
773 	if (err)
774 		return err;
775 
776 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
777 	if (IS_ERR(data->hwmon_dev)) {
778 		err = PTR_ERR(data->hwmon_dev);
779 		goto exit_remove_files;
780 	}
781 
782 	return 0;
783 
784 exit_remove_files:
785 	sysfs_remove_group(&pdev->dev.kobj, &via686a_group);
786 	return err;
787 }
788 
789 static int via686a_remove(struct platform_device *pdev)
790 {
791 	struct via686a_data *data = platform_get_drvdata(pdev);
792 
793 	hwmon_device_unregister(data->hwmon_dev);
794 	sysfs_remove_group(&pdev->dev.kobj, &via686a_group);
795 
796 	return 0;
797 }
798 
799 static struct platform_driver via686a_driver = {
800 	.driver = {
801 		.name	= DRIVER_NAME,
802 	},
803 	.probe		= via686a_probe,
804 	.remove		= via686a_remove,
805 };
806 
807 static const struct pci_device_id via686a_pci_ids[] = {
808 	{ PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686_4) },
809 	{ }
810 };
811 MODULE_DEVICE_TABLE(pci, via686a_pci_ids);
812 
813 static int via686a_device_add(unsigned short address)
814 {
815 	struct resource res = {
816 		.start	= address,
817 		.end	= address + VIA686A_EXTENT - 1,
818 		.name	= DRIVER_NAME,
819 		.flags	= IORESOURCE_IO,
820 	};
821 	int err;
822 
823 	err = acpi_check_resource_conflict(&res);
824 	if (err)
825 		goto exit;
826 
827 	pdev = platform_device_alloc(DRIVER_NAME, address);
828 	if (!pdev) {
829 		err = -ENOMEM;
830 		pr_err("Device allocation failed\n");
831 		goto exit;
832 	}
833 
834 	err = platform_device_add_resources(pdev, &res, 1);
835 	if (err) {
836 		pr_err("Device resource addition failed (%d)\n", err);
837 		goto exit_device_put;
838 	}
839 
840 	err = platform_device_add(pdev);
841 	if (err) {
842 		pr_err("Device addition failed (%d)\n", err);
843 		goto exit_device_put;
844 	}
845 
846 	return 0;
847 
848 exit_device_put:
849 	platform_device_put(pdev);
850 exit:
851 	return err;
852 }
853 
854 static int via686a_pci_probe(struct pci_dev *dev,
855 				       const struct pci_device_id *id)
856 {
857 	u16 address, val;
858 	int ret;
859 
860 	if (force_addr) {
861 		address = force_addr & ~(VIA686A_EXTENT - 1);
862 		dev_warn(&dev->dev, "Forcing ISA address 0x%x\n", address);
863 		ret = pci_write_config_word(dev, VIA686A_BASE_REG, address | 1);
864 		if (ret != PCIBIOS_SUCCESSFUL)
865 			return -ENODEV;
866 	}
867 	ret = pci_read_config_word(dev, VIA686A_BASE_REG, &val);
868 	if (ret != PCIBIOS_SUCCESSFUL)
869 		return -ENODEV;
870 
871 	address = val & ~(VIA686A_EXTENT - 1);
872 	if (address == 0) {
873 		dev_err(&dev->dev,
874 			"base address not set - upgrade BIOS or use force_addr=0xaddr\n");
875 		return -ENODEV;
876 	}
877 
878 	ret = pci_read_config_word(dev, VIA686A_ENABLE_REG, &val);
879 	if (ret != PCIBIOS_SUCCESSFUL)
880 		return -ENODEV;
881 	if (!(val & 0x0001)) {
882 		if (!force_addr) {
883 			dev_warn(&dev->dev,
884 				 "Sensors disabled, enable with force_addr=0x%x\n",
885 				 address);
886 			return -ENODEV;
887 		}
888 
889 		dev_warn(&dev->dev, "Enabling sensors\n");
890 		ret = pci_write_config_word(dev, VIA686A_ENABLE_REG, val | 0x1);
891 		if (ret != PCIBIOS_SUCCESSFUL)
892 			return -ENODEV;
893 	}
894 
895 	if (platform_driver_register(&via686a_driver))
896 		goto exit;
897 
898 	/* Sets global pdev as a side effect */
899 	if (via686a_device_add(address))
900 		goto exit_unregister;
901 
902 	/*
903 	 * Always return failure here.  This is to allow other drivers to bind
904 	 * to this pci device.  We don't really want to have control over the
905 	 * pci device, we only wanted to read as few register values from it.
906 	 */
907 	s_bridge = pci_dev_get(dev);
908 	return -ENODEV;
909 
910 exit_unregister:
911 	platform_driver_unregister(&via686a_driver);
912 exit:
913 	return -ENODEV;
914 }
915 
916 static struct pci_driver via686a_pci_driver = {
917 	.name		= DRIVER_NAME,
918 	.id_table	= via686a_pci_ids,
919 	.probe		= via686a_pci_probe,
920 };
921 
922 static int __init sm_via686a_init(void)
923 {
924 	return pci_register_driver(&via686a_pci_driver);
925 }
926 
927 static void __exit sm_via686a_exit(void)
928 {
929 	pci_unregister_driver(&via686a_pci_driver);
930 	if (s_bridge != NULL) {
931 		platform_device_unregister(pdev);
932 		platform_driver_unregister(&via686a_driver);
933 		pci_dev_put(s_bridge);
934 		s_bridge = NULL;
935 	}
936 }
937 
938 MODULE_AUTHOR("Kyösti Mälkki <kmalkki@cc.hut.fi>, "
939 	      "Mark Studebaker <mdsxyz123@yahoo.com> "
940 	      "and Bob Dougherty <bobd@stanford.edu>");
941 MODULE_DESCRIPTION("VIA 686A Sensor device");
942 MODULE_LICENSE("GPL");
943 
944 module_init(sm_via686a_init);
945 module_exit(sm_via686a_exit);
946