xref: /openbmc/linux/drivers/hwmon/vt8231.c (revision e3b9f1e8)
1 /*
2  * vt8231.c - Part of lm_sensors, Linux kernel modules
3  *	      for hardware monitoring
4  *
5  * Copyright (c) 2005 Roger Lucas <vt8231@hiddenengine.co.uk>
6  * Copyright (c) 2002 Mark D. Studebaker <mdsxyz123@yahoo.com>
7  *		      Aaron M. Marsh <amarsh@sdf.lonestar.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23 
24 /*
25  * Supports VIA VT8231 South Bridge embedded sensors
26  */
27 
28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
29 
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/slab.h>
33 #include <linux/pci.h>
34 #include <linux/jiffies.h>
35 #include <linux/platform_device.h>
36 #include <linux/hwmon.h>
37 #include <linux/hwmon-sysfs.h>
38 #include <linux/hwmon-vid.h>
39 #include <linux/err.h>
40 #include <linux/mutex.h>
41 #include <linux/acpi.h>
42 #include <linux/io.h>
43 
44 static int force_addr;
45 module_param(force_addr, int, 0);
46 MODULE_PARM_DESC(force_addr, "Initialize the base address of the sensors");
47 
48 static struct platform_device *pdev;
49 
50 #define VT8231_EXTENT 0x80
51 #define VT8231_BASE_REG 0x70
52 #define VT8231_ENABLE_REG 0x74
53 
54 /*
55  * The VT8231 registers
56  *
57  * The reset value for the input channel configuration is used (Reg 0x4A=0x07)
58  * which sets the selected inputs marked with '*' below if multiple options are
59  * possible:
60  *
61  *		    Voltage Mode	  Temperature Mode
62  *	Sensor	      Linux Id	      Linux Id	      VIA Id
63  *	--------      --------	      --------	      ------
64  *	CPU Diode	N/A		temp1		0
65  *	UIC1		in0		temp2 *		1
66  *	UIC2		in1 *		temp3		2
67  *	UIC3		in2 *		temp4		3
68  *	UIC4		in3 *		temp5		4
69  *	UIC5		in4 *		temp6		5
70  *	3.3V		in5		N/A
71  *
72  * Note that the BIOS may set the configuration register to a different value
73  * to match the motherboard configuration.
74  */
75 
76 /* fans numbered 0-1 */
77 #define VT8231_REG_FAN_MIN(nr)	(0x3b + (nr))
78 #define VT8231_REG_FAN(nr)	(0x29 + (nr))
79 
80 /* Voltage inputs numbered 0-5 */
81 
82 static const u8 regvolt[]    = { 0x21, 0x22, 0x23, 0x24, 0x25, 0x26 };
83 static const u8 regvoltmax[] = { 0x3d, 0x2b, 0x2d, 0x2f, 0x31, 0x33 };
84 static const u8 regvoltmin[] = { 0x3e, 0x2c, 0x2e, 0x30, 0x32, 0x34 };
85 
86 /*
87  * Temperatures are numbered 1-6 according to the Linux kernel specification.
88  *
89  * In the VIA datasheet, however, the temperatures are numbered from zero.
90  * Since it is important that this driver can easily be compared to the VIA
91  * datasheet, we will use the VIA numbering within this driver and map the
92  * kernel sysfs device name to the VIA number in the sysfs callback.
93  */
94 
95 #define VT8231_REG_TEMP_LOW01	0x49
96 #define VT8231_REG_TEMP_LOW25	0x4d
97 
98 static const u8 regtemp[]    = { 0x1f, 0x21, 0x22, 0x23, 0x24, 0x25 };
99 static const u8 regtempmax[] = { 0x39, 0x3d, 0x2b, 0x2d, 0x2f, 0x31 };
100 static const u8 regtempmin[] = { 0x3a, 0x3e, 0x2c, 0x2e, 0x30, 0x32 };
101 
102 #define TEMP_FROM_REG(reg)		(((253 * 4 - (reg)) * 550 + 105) / 210)
103 #define TEMP_MAXMIN_FROM_REG(reg)	(((253 - (reg)) * 2200 + 105) / 210)
104 #define TEMP_MAXMIN_TO_REG(val)		(253 - ((val) * 210 + 1100) / 2200)
105 
106 #define VT8231_REG_CONFIG 0x40
107 #define VT8231_REG_ALARM1 0x41
108 #define VT8231_REG_ALARM2 0x42
109 #define VT8231_REG_FANDIV 0x47
110 #define VT8231_REG_UCH_CONFIG 0x4a
111 #define VT8231_REG_TEMP1_CONFIG 0x4b
112 #define VT8231_REG_TEMP2_CONFIG 0x4c
113 
114 /*
115  * temps 0-5 as numbered in VIA datasheet - see later for mapping to Linux
116  * numbering
117  */
118 #define ISTEMP(i, ch_config) ((i) == 0 ? 1 : \
119 			      ((ch_config) >> ((i)+1)) & 0x01)
120 /* voltages 0-5 */
121 #define ISVOLT(i, ch_config) ((i) == 5 ? 1 : \
122 			      !(((ch_config) >> ((i)+2)) & 0x01))
123 
124 #define DIV_FROM_REG(val) (1 << (val))
125 
126 /*
127  * NB  The values returned here are NOT temperatures.  The calibration curves
128  *     for the thermistor curves are board-specific and must go in the
129  *     sensors.conf file.  Temperature sensors are actually ten bits, but the
130  *     VIA datasheet only considers the 8 MSBs obtained from the regtemp[]
131  *     register.  The temperature value returned should have a magnitude of 3,
132  *     so we use the VIA scaling as the "true" scaling and use the remaining 2
133  *     LSBs as fractional precision.
134  *
135  *     All the on-chip hardware temperature comparisons for the alarms are only
136  *     8-bits wide, and compare against the 8 MSBs of the temperature.  The bits
137  *     in the registers VT8231_REG_TEMP_LOW01 and VT8231_REG_TEMP_LOW25 are
138  *     ignored.
139  */
140 
141 /*
142  ****** FAN RPM CONVERSIONS ********
143  * This chip saturates back at 0, not at 255 like many the other chips.
144  * So, 0 means 0 RPM
145  */
146 static inline u8 FAN_TO_REG(long rpm, int div)
147 {
148 	if (rpm <= 0 || rpm > 1310720)
149 		return 0;
150 	return clamp_val(1310720 / (rpm * div), 1, 255);
151 }
152 
153 #define FAN_FROM_REG(val, div) ((val) == 0 ? 0 : 1310720 / ((val) * (div)))
154 
155 struct vt8231_data {
156 	unsigned short addr;
157 	const char *name;
158 
159 	struct mutex update_lock;
160 	struct device *hwmon_dev;
161 	char valid;		/* !=0 if following fields are valid */
162 	unsigned long last_updated;	/* In jiffies */
163 
164 	u8 in[6];		/* Register value */
165 	u8 in_max[6];		/* Register value */
166 	u8 in_min[6];		/* Register value */
167 	u16 temp[6];		/* Register value 10 bit, right aligned */
168 	u8 temp_max[6];		/* Register value */
169 	u8 temp_min[6];		/* Register value */
170 	u8 fan[2];		/* Register value */
171 	u8 fan_min[2];		/* Register value */
172 	u8 fan_div[2];		/* Register encoding, shifted right */
173 	u16 alarms;		/* Register encoding */
174 	u8 uch_config;
175 };
176 
177 static struct pci_dev *s_bridge;
178 static int vt8231_probe(struct platform_device *pdev);
179 static int vt8231_remove(struct platform_device *pdev);
180 static struct vt8231_data *vt8231_update_device(struct device *dev);
181 static void vt8231_init_device(struct vt8231_data *data);
182 
183 static inline int vt8231_read_value(struct vt8231_data *data, u8 reg)
184 {
185 	return inb_p(data->addr + reg);
186 }
187 
188 static inline void vt8231_write_value(struct vt8231_data *data, u8 reg,
189 					u8 value)
190 {
191 	outb_p(value, data->addr + reg);
192 }
193 
194 /* following are the sysfs callback functions */
195 static ssize_t show_in(struct device *dev, struct device_attribute *attr,
196 		char *buf)
197 {
198 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
199 	int nr = sensor_attr->index;
200 	struct vt8231_data *data = vt8231_update_device(dev);
201 
202 	return sprintf(buf, "%d\n", ((data->in[nr] - 3) * 10000) / 958);
203 }
204 
205 static ssize_t show_in_min(struct device *dev, struct device_attribute *attr,
206 		char *buf)
207 {
208 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
209 	int nr = sensor_attr->index;
210 	struct vt8231_data *data = vt8231_update_device(dev);
211 
212 	return sprintf(buf, "%d\n", ((data->in_min[nr] - 3) * 10000) / 958);
213 }
214 
215 static ssize_t show_in_max(struct device *dev, struct device_attribute *attr,
216 		char *buf)
217 {
218 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
219 	int nr = sensor_attr->index;
220 	struct vt8231_data *data = vt8231_update_device(dev);
221 
222 	return sprintf(buf, "%d\n", (((data->in_max[nr] - 3) * 10000) / 958));
223 }
224 
225 static ssize_t set_in_min(struct device *dev, struct device_attribute *attr,
226 		const char *buf, size_t count)
227 {
228 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
229 	int nr = sensor_attr->index;
230 	struct vt8231_data *data = dev_get_drvdata(dev);
231 	unsigned long val;
232 	int err;
233 
234 	err = kstrtoul(buf, 10, &val);
235 	if (err)
236 		return err;
237 
238 	mutex_lock(&data->update_lock);
239 	data->in_min[nr] = clamp_val(((val * 958) / 10000) + 3, 0, 255);
240 	vt8231_write_value(data, regvoltmin[nr], data->in_min[nr]);
241 	mutex_unlock(&data->update_lock);
242 	return count;
243 }
244 
245 static ssize_t set_in_max(struct device *dev, struct device_attribute *attr,
246 		const char *buf, size_t count)
247 {
248 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
249 	int nr = sensor_attr->index;
250 	struct vt8231_data *data = dev_get_drvdata(dev);
251 	unsigned long val;
252 	int err;
253 
254 	err = kstrtoul(buf, 10, &val);
255 	if (err)
256 		return err;
257 
258 	mutex_lock(&data->update_lock);
259 	data->in_max[nr] = clamp_val(((val * 958) / 10000) + 3, 0, 255);
260 	vt8231_write_value(data, regvoltmax[nr], data->in_max[nr]);
261 	mutex_unlock(&data->update_lock);
262 	return count;
263 }
264 
265 /* Special case for input 5 as this has 3.3V scaling built into the chip */
266 static ssize_t in5_input_show(struct device *dev,
267 			      struct device_attribute *attr, char *buf)
268 {
269 	struct vt8231_data *data = vt8231_update_device(dev);
270 
271 	return sprintf(buf, "%d\n",
272 		(((data->in[5] - 3) * 10000 * 54) / (958 * 34)));
273 }
274 
275 static ssize_t in5_min_show(struct device *dev, struct device_attribute *attr,
276 		char *buf)
277 {
278 	struct vt8231_data *data = vt8231_update_device(dev);
279 
280 	return sprintf(buf, "%d\n",
281 		(((data->in_min[5] - 3) * 10000 * 54) / (958 * 34)));
282 }
283 
284 static ssize_t in5_max_show(struct device *dev, struct device_attribute *attr,
285 		char *buf)
286 {
287 	struct vt8231_data *data = vt8231_update_device(dev);
288 
289 	return sprintf(buf, "%d\n",
290 		(((data->in_max[5] - 3) * 10000 * 54) / (958 * 34)));
291 }
292 
293 static ssize_t in5_min_store(struct device *dev,
294 			     struct device_attribute *attr, const char *buf,
295 			     size_t count)
296 {
297 	struct vt8231_data *data = dev_get_drvdata(dev);
298 	unsigned long val;
299 	int err;
300 
301 	err = kstrtoul(buf, 10, &val);
302 	if (err)
303 		return err;
304 
305 	mutex_lock(&data->update_lock);
306 	data->in_min[5] = clamp_val(((val * 958 * 34) / (10000 * 54)) + 3,
307 				    0, 255);
308 	vt8231_write_value(data, regvoltmin[5], data->in_min[5]);
309 	mutex_unlock(&data->update_lock);
310 	return count;
311 }
312 
313 static ssize_t in5_max_store(struct device *dev,
314 			     struct device_attribute *attr, const char *buf,
315 			     size_t count)
316 {
317 	struct vt8231_data *data = dev_get_drvdata(dev);
318 	unsigned long val;
319 	int err;
320 
321 	err = kstrtoul(buf, 10, &val);
322 	if (err)
323 		return err;
324 
325 	mutex_lock(&data->update_lock);
326 	data->in_max[5] = clamp_val(((val * 958 * 34) / (10000 * 54)) + 3,
327 				    0, 255);
328 	vt8231_write_value(data, regvoltmax[5], data->in_max[5]);
329 	mutex_unlock(&data->update_lock);
330 	return count;
331 }
332 
333 #define define_voltage_sysfs(offset)				\
334 static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
335 		show_in, NULL, offset);				\
336 static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
337 		show_in_min, set_in_min, offset);		\
338 static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
339 		show_in_max, set_in_max, offset)
340 
341 define_voltage_sysfs(0);
342 define_voltage_sysfs(1);
343 define_voltage_sysfs(2);
344 define_voltage_sysfs(3);
345 define_voltage_sysfs(4);
346 
347 static DEVICE_ATTR_RO(in5_input);
348 static DEVICE_ATTR_RW(in5_min);
349 static DEVICE_ATTR_RW(in5_max);
350 
351 /* Temperatures */
352 static ssize_t temp1_input_show(struct device *dev,
353 				struct device_attribute *attr, char *buf)
354 {
355 	struct vt8231_data *data = vt8231_update_device(dev);
356 	return sprintf(buf, "%d\n", data->temp[0] * 250);
357 }
358 
359 static ssize_t temp1_max_show(struct device *dev, struct device_attribute *attr,
360 		char *buf)
361 {
362 	struct vt8231_data *data = vt8231_update_device(dev);
363 	return sprintf(buf, "%d\n", data->temp_max[0] * 1000);
364 }
365 
366 static ssize_t temp1_max_hyst_show(struct device *dev,
367 				   struct device_attribute *attr, char *buf)
368 {
369 	struct vt8231_data *data = vt8231_update_device(dev);
370 	return sprintf(buf, "%d\n", data->temp_min[0] * 1000);
371 }
372 
373 static ssize_t temp1_max_store(struct device *dev,
374 			       struct device_attribute *attr, const char *buf,
375 			       size_t count)
376 {
377 	struct vt8231_data *data = dev_get_drvdata(dev);
378 	long val;
379 	int err;
380 
381 	err = kstrtol(buf, 10, &val);
382 	if (err)
383 		return err;
384 
385 	mutex_lock(&data->update_lock);
386 	data->temp_max[0] = clamp_val((val + 500) / 1000, 0, 255);
387 	vt8231_write_value(data, regtempmax[0], data->temp_max[0]);
388 	mutex_unlock(&data->update_lock);
389 	return count;
390 }
391 static ssize_t temp1_max_hyst_store(struct device *dev,
392 				    struct device_attribute *attr,
393 				    const char *buf, size_t count)
394 {
395 	struct vt8231_data *data = dev_get_drvdata(dev);
396 	long val;
397 	int err;
398 
399 	err = kstrtol(buf, 10, &val);
400 	if (err)
401 		return err;
402 
403 	mutex_lock(&data->update_lock);
404 	data->temp_min[0] = clamp_val((val + 500) / 1000, 0, 255);
405 	vt8231_write_value(data, regtempmin[0], data->temp_min[0]);
406 	mutex_unlock(&data->update_lock);
407 	return count;
408 }
409 
410 static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
411 		char *buf)
412 {
413 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
414 	int nr = sensor_attr->index;
415 	struct vt8231_data *data = vt8231_update_device(dev);
416 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
417 }
418 
419 static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr,
420 		char *buf)
421 {
422 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
423 	int nr = sensor_attr->index;
424 	struct vt8231_data *data = vt8231_update_device(dev);
425 	return sprintf(buf, "%d\n", TEMP_MAXMIN_FROM_REG(data->temp_max[nr]));
426 }
427 
428 static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
429 		char *buf)
430 {
431 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
432 	int nr = sensor_attr->index;
433 	struct vt8231_data *data = vt8231_update_device(dev);
434 	return sprintf(buf, "%d\n", TEMP_MAXMIN_FROM_REG(data->temp_min[nr]));
435 }
436 
437 static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
438 		const char *buf, size_t count)
439 {
440 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
441 	int nr = sensor_attr->index;
442 	struct vt8231_data *data = dev_get_drvdata(dev);
443 	long val;
444 	int err;
445 
446 	err = kstrtol(buf, 10, &val);
447 	if (err)
448 		return err;
449 
450 	mutex_lock(&data->update_lock);
451 	data->temp_max[nr] = clamp_val(TEMP_MAXMIN_TO_REG(val), 0, 255);
452 	vt8231_write_value(data, regtempmax[nr], data->temp_max[nr]);
453 	mutex_unlock(&data->update_lock);
454 	return count;
455 }
456 static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
457 		const char *buf, size_t count)
458 {
459 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
460 	int nr = sensor_attr->index;
461 	struct vt8231_data *data = dev_get_drvdata(dev);
462 	long val;
463 	int err;
464 
465 	err = kstrtol(buf, 10, &val);
466 	if (err)
467 		return err;
468 
469 	mutex_lock(&data->update_lock);
470 	data->temp_min[nr] = clamp_val(TEMP_MAXMIN_TO_REG(val), 0, 255);
471 	vt8231_write_value(data, regtempmin[nr], data->temp_min[nr]);
472 	mutex_unlock(&data->update_lock);
473 	return count;
474 }
475 
476 /*
477  * Note that these map the Linux temperature sensor numbering (1-6) to the VIA
478  * temperature sensor numbering (0-5)
479  */
480 #define define_temperature_sysfs(offset)				\
481 static SENSOR_DEVICE_ATTR(temp##offset##_input, S_IRUGO,		\
482 		show_temp, NULL, offset - 1);				\
483 static SENSOR_DEVICE_ATTR(temp##offset##_max, S_IRUGO | S_IWUSR,	\
484 		show_temp_max, set_temp_max, offset - 1);		\
485 static SENSOR_DEVICE_ATTR(temp##offset##_max_hyst, S_IRUGO | S_IWUSR,	\
486 		show_temp_min, set_temp_min, offset - 1)
487 
488 static DEVICE_ATTR_RO(temp1_input);
489 static DEVICE_ATTR_RW(temp1_max);
490 static DEVICE_ATTR_RW(temp1_max_hyst);
491 
492 define_temperature_sysfs(2);
493 define_temperature_sysfs(3);
494 define_temperature_sysfs(4);
495 define_temperature_sysfs(5);
496 define_temperature_sysfs(6);
497 
498 /* Fans */
499 static ssize_t show_fan(struct device *dev, struct device_attribute *attr,
500 		char *buf)
501 {
502 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
503 	int nr = sensor_attr->index;
504 	struct vt8231_data *data = vt8231_update_device(dev);
505 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
506 				DIV_FROM_REG(data->fan_div[nr])));
507 }
508 
509 static ssize_t show_fan_min(struct device *dev, struct device_attribute *attr,
510 		char *buf)
511 {
512 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
513 	int nr = sensor_attr->index;
514 	struct vt8231_data *data = vt8231_update_device(dev);
515 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
516 			DIV_FROM_REG(data->fan_div[nr])));
517 }
518 
519 static ssize_t show_fan_div(struct device *dev, struct device_attribute *attr,
520 		char *buf)
521 {
522 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
523 	int nr = sensor_attr->index;
524 	struct vt8231_data *data = vt8231_update_device(dev);
525 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
526 }
527 
528 static ssize_t set_fan_min(struct device *dev, struct device_attribute *attr,
529 		const char *buf, size_t count)
530 {
531 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
532 	int nr = sensor_attr->index;
533 	struct vt8231_data *data = dev_get_drvdata(dev);
534 	unsigned long val;
535 	int err;
536 
537 	err = kstrtoul(buf, 10, &val);
538 	if (err)
539 		return err;
540 
541 	mutex_lock(&data->update_lock);
542 	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
543 	vt8231_write_value(data, VT8231_REG_FAN_MIN(nr), data->fan_min[nr]);
544 	mutex_unlock(&data->update_lock);
545 	return count;
546 }
547 
548 static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr,
549 		const char *buf, size_t count)
550 {
551 	struct vt8231_data *data = dev_get_drvdata(dev);
552 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
553 	unsigned long val;
554 	int nr = sensor_attr->index;
555 	int old = vt8231_read_value(data, VT8231_REG_FANDIV);
556 	long min = FAN_FROM_REG(data->fan_min[nr],
557 				 DIV_FROM_REG(data->fan_div[nr]));
558 	int err;
559 
560 	err = kstrtoul(buf, 10, &val);
561 	if (err)
562 		return err;
563 
564 	mutex_lock(&data->update_lock);
565 	switch (val) {
566 	case 1:
567 		data->fan_div[nr] = 0;
568 		break;
569 	case 2:
570 		data->fan_div[nr] = 1;
571 		break;
572 	case 4:
573 		data->fan_div[nr] = 2;
574 		break;
575 	case 8:
576 		data->fan_div[nr] = 3;
577 		break;
578 	default:
579 		dev_err(dev,
580 			"fan_div value %ld not supported. Choose one of 1, 2, 4 or 8!\n",
581 			val);
582 		mutex_unlock(&data->update_lock);
583 		return -EINVAL;
584 	}
585 
586 	/* Correct the fan minimum speed */
587 	data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
588 	vt8231_write_value(data, VT8231_REG_FAN_MIN(nr), data->fan_min[nr]);
589 
590 	old = (old & 0x0f) | (data->fan_div[1] << 6) | (data->fan_div[0] << 4);
591 	vt8231_write_value(data, VT8231_REG_FANDIV, old);
592 	mutex_unlock(&data->update_lock);
593 	return count;
594 }
595 
596 
597 #define define_fan_sysfs(offset)					\
598 static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO,			\
599 		show_fan, NULL, offset - 1);				\
600 static SENSOR_DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
601 		show_fan_div, set_fan_div, offset - 1);			\
602 static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
603 		show_fan_min, set_fan_min, offset - 1)
604 
605 define_fan_sysfs(1);
606 define_fan_sysfs(2);
607 
608 /* Alarms */
609 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
610 			   char *buf)
611 {
612 	struct vt8231_data *data = vt8231_update_device(dev);
613 	return sprintf(buf, "%d\n", data->alarms);
614 }
615 static DEVICE_ATTR_RO(alarms);
616 
617 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
618 			  char *buf)
619 {
620 	int bitnr = to_sensor_dev_attr(attr)->index;
621 	struct vt8231_data *data = vt8231_update_device(dev);
622 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
623 }
624 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
625 static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 11);
626 static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 0);
627 static SENSOR_DEVICE_ATTR(temp4_alarm, S_IRUGO, show_alarm, NULL, 1);
628 static SENSOR_DEVICE_ATTR(temp5_alarm, S_IRUGO, show_alarm, NULL, 3);
629 static SENSOR_DEVICE_ATTR(temp6_alarm, S_IRUGO, show_alarm, NULL, 8);
630 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 11);
631 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 0);
632 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 1);
633 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
634 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 8);
635 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 2);
636 static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL, 6);
637 static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);
638 
639 static ssize_t name_show(struct device *dev, struct device_attribute
640 			 *devattr, char *buf)
641 {
642 	struct vt8231_data *data = dev_get_drvdata(dev);
643 	return sprintf(buf, "%s\n", data->name);
644 }
645 static DEVICE_ATTR_RO(name);
646 
647 static struct attribute *vt8231_attributes_temps[6][5] = {
648 	{
649 		&dev_attr_temp1_input.attr,
650 		&dev_attr_temp1_max_hyst.attr,
651 		&dev_attr_temp1_max.attr,
652 		&sensor_dev_attr_temp1_alarm.dev_attr.attr,
653 		NULL
654 	}, {
655 		&sensor_dev_attr_temp2_input.dev_attr.attr,
656 		&sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
657 		&sensor_dev_attr_temp2_max.dev_attr.attr,
658 		&sensor_dev_attr_temp2_alarm.dev_attr.attr,
659 		NULL
660 	}, {
661 		&sensor_dev_attr_temp3_input.dev_attr.attr,
662 		&sensor_dev_attr_temp3_max_hyst.dev_attr.attr,
663 		&sensor_dev_attr_temp3_max.dev_attr.attr,
664 		&sensor_dev_attr_temp3_alarm.dev_attr.attr,
665 		NULL
666 	}, {
667 		&sensor_dev_attr_temp4_input.dev_attr.attr,
668 		&sensor_dev_attr_temp4_max_hyst.dev_attr.attr,
669 		&sensor_dev_attr_temp4_max.dev_attr.attr,
670 		&sensor_dev_attr_temp4_alarm.dev_attr.attr,
671 		NULL
672 	}, {
673 		&sensor_dev_attr_temp5_input.dev_attr.attr,
674 		&sensor_dev_attr_temp5_max_hyst.dev_attr.attr,
675 		&sensor_dev_attr_temp5_max.dev_attr.attr,
676 		&sensor_dev_attr_temp5_alarm.dev_attr.attr,
677 		NULL
678 	}, {
679 		&sensor_dev_attr_temp6_input.dev_attr.attr,
680 		&sensor_dev_attr_temp6_max_hyst.dev_attr.attr,
681 		&sensor_dev_attr_temp6_max.dev_attr.attr,
682 		&sensor_dev_attr_temp6_alarm.dev_attr.attr,
683 		NULL
684 	}
685 };
686 
687 static const struct attribute_group vt8231_group_temps[6] = {
688 	{ .attrs = vt8231_attributes_temps[0] },
689 	{ .attrs = vt8231_attributes_temps[1] },
690 	{ .attrs = vt8231_attributes_temps[2] },
691 	{ .attrs = vt8231_attributes_temps[3] },
692 	{ .attrs = vt8231_attributes_temps[4] },
693 	{ .attrs = vt8231_attributes_temps[5] },
694 };
695 
696 static struct attribute *vt8231_attributes_volts[6][5] = {
697 	{
698 		&sensor_dev_attr_in0_input.dev_attr.attr,
699 		&sensor_dev_attr_in0_min.dev_attr.attr,
700 		&sensor_dev_attr_in0_max.dev_attr.attr,
701 		&sensor_dev_attr_in0_alarm.dev_attr.attr,
702 		NULL
703 	}, {
704 		&sensor_dev_attr_in1_input.dev_attr.attr,
705 		&sensor_dev_attr_in1_min.dev_attr.attr,
706 		&sensor_dev_attr_in1_max.dev_attr.attr,
707 		&sensor_dev_attr_in1_alarm.dev_attr.attr,
708 		NULL
709 	}, {
710 		&sensor_dev_attr_in2_input.dev_attr.attr,
711 		&sensor_dev_attr_in2_min.dev_attr.attr,
712 		&sensor_dev_attr_in2_max.dev_attr.attr,
713 		&sensor_dev_attr_in2_alarm.dev_attr.attr,
714 		NULL
715 	}, {
716 		&sensor_dev_attr_in3_input.dev_attr.attr,
717 		&sensor_dev_attr_in3_min.dev_attr.attr,
718 		&sensor_dev_attr_in3_max.dev_attr.attr,
719 		&sensor_dev_attr_in3_alarm.dev_attr.attr,
720 		NULL
721 	}, {
722 		&sensor_dev_attr_in4_input.dev_attr.attr,
723 		&sensor_dev_attr_in4_min.dev_attr.attr,
724 		&sensor_dev_attr_in4_max.dev_attr.attr,
725 		&sensor_dev_attr_in4_alarm.dev_attr.attr,
726 		NULL
727 	}, {
728 		&dev_attr_in5_input.attr,
729 		&dev_attr_in5_min.attr,
730 		&dev_attr_in5_max.attr,
731 		&sensor_dev_attr_in5_alarm.dev_attr.attr,
732 		NULL
733 	}
734 };
735 
736 static const struct attribute_group vt8231_group_volts[6] = {
737 	{ .attrs = vt8231_attributes_volts[0] },
738 	{ .attrs = vt8231_attributes_volts[1] },
739 	{ .attrs = vt8231_attributes_volts[2] },
740 	{ .attrs = vt8231_attributes_volts[3] },
741 	{ .attrs = vt8231_attributes_volts[4] },
742 	{ .attrs = vt8231_attributes_volts[5] },
743 };
744 
745 static struct attribute *vt8231_attributes[] = {
746 	&sensor_dev_attr_fan1_input.dev_attr.attr,
747 	&sensor_dev_attr_fan2_input.dev_attr.attr,
748 	&sensor_dev_attr_fan1_min.dev_attr.attr,
749 	&sensor_dev_attr_fan2_min.dev_attr.attr,
750 	&sensor_dev_attr_fan1_div.dev_attr.attr,
751 	&sensor_dev_attr_fan2_div.dev_attr.attr,
752 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
753 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
754 	&dev_attr_alarms.attr,
755 	&dev_attr_name.attr,
756 	NULL
757 };
758 
759 static const struct attribute_group vt8231_group = {
760 	.attrs = vt8231_attributes,
761 };
762 
763 static struct platform_driver vt8231_driver = {
764 	.driver = {
765 		.name	= "vt8231",
766 	},
767 	.probe	= vt8231_probe,
768 	.remove	= vt8231_remove,
769 };
770 
771 static const struct pci_device_id vt8231_pci_ids[] = {
772 	{ PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231_4) },
773 	{ 0, }
774 };
775 
776 MODULE_DEVICE_TABLE(pci, vt8231_pci_ids);
777 
778 static int vt8231_pci_probe(struct pci_dev *dev,
779 				      const struct pci_device_id *id);
780 
781 static struct pci_driver vt8231_pci_driver = {
782 	.name		= "vt8231",
783 	.id_table	= vt8231_pci_ids,
784 	.probe		= vt8231_pci_probe,
785 };
786 
787 static int vt8231_probe(struct platform_device *pdev)
788 {
789 	struct resource *res;
790 	struct vt8231_data *data;
791 	int err = 0, i;
792 
793 	/* Reserve the ISA region */
794 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
795 	if (!devm_request_region(&pdev->dev, res->start, VT8231_EXTENT,
796 				 vt8231_driver.driver.name)) {
797 		dev_err(&pdev->dev, "Region 0x%lx-0x%lx already in use!\n",
798 			(unsigned long)res->start, (unsigned long)res->end);
799 		return -ENODEV;
800 	}
801 
802 	data = devm_kzalloc(&pdev->dev, sizeof(struct vt8231_data), GFP_KERNEL);
803 	if (!data)
804 		return -ENOMEM;
805 
806 	platform_set_drvdata(pdev, data);
807 	data->addr = res->start;
808 	data->name = "vt8231";
809 
810 	mutex_init(&data->update_lock);
811 	vt8231_init_device(data);
812 
813 	/* Register sysfs hooks */
814 	err = sysfs_create_group(&pdev->dev.kobj, &vt8231_group);
815 	if (err)
816 		return err;
817 
818 	/* Must update device information to find out the config field */
819 	data->uch_config = vt8231_read_value(data, VT8231_REG_UCH_CONFIG);
820 
821 	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++) {
822 		if (ISTEMP(i, data->uch_config)) {
823 			err = sysfs_create_group(&pdev->dev.kobj,
824 						 &vt8231_group_temps[i]);
825 			if (err)
826 				goto exit_remove_files;
827 		}
828 	}
829 
830 	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++) {
831 		if (ISVOLT(i, data->uch_config)) {
832 			err = sysfs_create_group(&pdev->dev.kobj,
833 						 &vt8231_group_volts[i]);
834 			if (err)
835 				goto exit_remove_files;
836 		}
837 	}
838 
839 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
840 	if (IS_ERR(data->hwmon_dev)) {
841 		err = PTR_ERR(data->hwmon_dev);
842 		goto exit_remove_files;
843 	}
844 	return 0;
845 
846 exit_remove_files:
847 	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++)
848 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_volts[i]);
849 
850 	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++)
851 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_temps[i]);
852 
853 	sysfs_remove_group(&pdev->dev.kobj, &vt8231_group);
854 	return err;
855 }
856 
857 static int vt8231_remove(struct platform_device *pdev)
858 {
859 	struct vt8231_data *data = platform_get_drvdata(pdev);
860 	int i;
861 
862 	hwmon_device_unregister(data->hwmon_dev);
863 
864 	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++)
865 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_volts[i]);
866 
867 	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++)
868 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_temps[i]);
869 
870 	sysfs_remove_group(&pdev->dev.kobj, &vt8231_group);
871 
872 	return 0;
873 }
874 
875 static void vt8231_init_device(struct vt8231_data *data)
876 {
877 	vt8231_write_value(data, VT8231_REG_TEMP1_CONFIG, 0);
878 	vt8231_write_value(data, VT8231_REG_TEMP2_CONFIG, 0);
879 }
880 
881 static struct vt8231_data *vt8231_update_device(struct device *dev)
882 {
883 	struct vt8231_data *data = dev_get_drvdata(dev);
884 	int i;
885 	u16 low;
886 
887 	mutex_lock(&data->update_lock);
888 
889 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
890 	    || !data->valid) {
891 		for (i = 0; i < 6; i++) {
892 			if (ISVOLT(i, data->uch_config)) {
893 				data->in[i] = vt8231_read_value(data,
894 						regvolt[i]);
895 				data->in_min[i] = vt8231_read_value(data,
896 						regvoltmin[i]);
897 				data->in_max[i] = vt8231_read_value(data,
898 						regvoltmax[i]);
899 			}
900 		}
901 		for (i = 0; i < 2; i++) {
902 			data->fan[i] = vt8231_read_value(data,
903 						VT8231_REG_FAN(i));
904 			data->fan_min[i] = vt8231_read_value(data,
905 						VT8231_REG_FAN_MIN(i));
906 		}
907 
908 		low = vt8231_read_value(data, VT8231_REG_TEMP_LOW01);
909 		low = (low >> 6) | ((low & 0x30) >> 2)
910 		    | (vt8231_read_value(data, VT8231_REG_TEMP_LOW25) << 4);
911 		for (i = 0; i < 6; i++) {
912 			if (ISTEMP(i, data->uch_config)) {
913 				data->temp[i] = (vt8231_read_value(data,
914 						       regtemp[i]) << 2)
915 						| ((low >> (2 * i)) & 0x03);
916 				data->temp_max[i] = vt8231_read_value(data,
917 						      regtempmax[i]);
918 				data->temp_min[i] = vt8231_read_value(data,
919 						      regtempmin[i]);
920 			}
921 		}
922 
923 		i = vt8231_read_value(data, VT8231_REG_FANDIV);
924 		data->fan_div[0] = (i >> 4) & 0x03;
925 		data->fan_div[1] = i >> 6;
926 		data->alarms = vt8231_read_value(data, VT8231_REG_ALARM1) |
927 			(vt8231_read_value(data, VT8231_REG_ALARM2) << 8);
928 
929 		/* Set alarm flags correctly */
930 		if (!data->fan[0] && data->fan_min[0])
931 			data->alarms |= 0x40;
932 		else if (data->fan[0] && !data->fan_min[0])
933 			data->alarms &= ~0x40;
934 
935 		if (!data->fan[1] && data->fan_min[1])
936 			data->alarms |= 0x80;
937 		else if (data->fan[1] && !data->fan_min[1])
938 			data->alarms &= ~0x80;
939 
940 		data->last_updated = jiffies;
941 		data->valid = 1;
942 	}
943 
944 	mutex_unlock(&data->update_lock);
945 
946 	return data;
947 }
948 
949 static int vt8231_device_add(unsigned short address)
950 {
951 	struct resource res = {
952 		.start	= address,
953 		.end	= address + VT8231_EXTENT - 1,
954 		.name	= "vt8231",
955 		.flags	= IORESOURCE_IO,
956 	};
957 	int err;
958 
959 	err = acpi_check_resource_conflict(&res);
960 	if (err)
961 		goto exit;
962 
963 	pdev = platform_device_alloc("vt8231", address);
964 	if (!pdev) {
965 		err = -ENOMEM;
966 		pr_err("Device allocation failed\n");
967 		goto exit;
968 	}
969 
970 	err = platform_device_add_resources(pdev, &res, 1);
971 	if (err) {
972 		pr_err("Device resource addition failed (%d)\n", err);
973 		goto exit_device_put;
974 	}
975 
976 	err = platform_device_add(pdev);
977 	if (err) {
978 		pr_err("Device addition failed (%d)\n", err);
979 		goto exit_device_put;
980 	}
981 
982 	return 0;
983 
984 exit_device_put:
985 	platform_device_put(pdev);
986 exit:
987 	return err;
988 }
989 
990 static int vt8231_pci_probe(struct pci_dev *dev,
991 				const struct pci_device_id *id)
992 {
993 	u16 address, val;
994 	if (force_addr) {
995 		address = force_addr & 0xff00;
996 		dev_warn(&dev->dev, "Forcing ISA address 0x%x\n",
997 			 address);
998 
999 		if (PCIBIOS_SUCCESSFUL !=
1000 		    pci_write_config_word(dev, VT8231_BASE_REG, address | 1))
1001 			return -ENODEV;
1002 	}
1003 
1004 	if (PCIBIOS_SUCCESSFUL != pci_read_config_word(dev, VT8231_BASE_REG,
1005 							&val))
1006 		return -ENODEV;
1007 
1008 	address = val & ~(VT8231_EXTENT - 1);
1009 	if (address == 0) {
1010 		dev_err(&dev->dev, "base address not set - upgrade BIOS or use force_addr=0xaddr\n");
1011 		return -ENODEV;
1012 	}
1013 
1014 	if (PCIBIOS_SUCCESSFUL != pci_read_config_word(dev, VT8231_ENABLE_REG,
1015 							&val))
1016 		return -ENODEV;
1017 
1018 	if (!(val & 0x0001)) {
1019 		dev_warn(&dev->dev, "enabling sensors\n");
1020 		if (PCIBIOS_SUCCESSFUL !=
1021 			pci_write_config_word(dev, VT8231_ENABLE_REG,
1022 							val | 0x0001))
1023 			return -ENODEV;
1024 	}
1025 
1026 	if (platform_driver_register(&vt8231_driver))
1027 		goto exit;
1028 
1029 	/* Sets global pdev as a side effect */
1030 	if (vt8231_device_add(address))
1031 		goto exit_unregister;
1032 
1033 	/*
1034 	 * Always return failure here.  This is to allow other drivers to bind
1035 	 * to this pci device.  We don't really want to have control over the
1036 	 * pci device, we only wanted to read as few register values from it.
1037 	 */
1038 
1039 	/*
1040 	 * We do, however, mark ourselves as using the PCI device to stop it
1041 	 * getting unloaded.
1042 	 */
1043 	s_bridge = pci_dev_get(dev);
1044 	return -ENODEV;
1045 
1046 exit_unregister:
1047 	platform_driver_unregister(&vt8231_driver);
1048 exit:
1049 	return -ENODEV;
1050 }
1051 
1052 static int __init sm_vt8231_init(void)
1053 {
1054 	return pci_register_driver(&vt8231_pci_driver);
1055 }
1056 
1057 static void __exit sm_vt8231_exit(void)
1058 {
1059 	pci_unregister_driver(&vt8231_pci_driver);
1060 	if (s_bridge != NULL) {
1061 		platform_device_unregister(pdev);
1062 		platform_driver_unregister(&vt8231_driver);
1063 		pci_dev_put(s_bridge);
1064 		s_bridge = NULL;
1065 	}
1066 }
1067 
1068 MODULE_AUTHOR("Roger Lucas <vt8231@hiddenengine.co.uk>");
1069 MODULE_DESCRIPTION("VT8231 sensors");
1070 MODULE_LICENSE("GPL");
1071 
1072 module_init(sm_vt8231_init);
1073 module_exit(sm_vt8231_exit);
1074