xref: /openbmc/linux/drivers/hwmon/vt8231.c (revision 293d5b43)
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 show_in5(struct device *dev, struct device_attribute *attr,
267 		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 show_in5_min(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 show_in5_max(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 set_in5_min(struct device *dev, struct device_attribute *attr,
294 		const char *buf, size_t count)
295 {
296 	struct vt8231_data *data = dev_get_drvdata(dev);
297 	unsigned long val;
298 	int err;
299 
300 	err = kstrtoul(buf, 10, &val);
301 	if (err)
302 		return err;
303 
304 	mutex_lock(&data->update_lock);
305 	data->in_min[5] = clamp_val(((val * 958 * 34) / (10000 * 54)) + 3,
306 				    0, 255);
307 	vt8231_write_value(data, regvoltmin[5], data->in_min[5]);
308 	mutex_unlock(&data->update_lock);
309 	return count;
310 }
311 
312 static ssize_t set_in5_max(struct device *dev, struct device_attribute *attr,
313 		const char *buf, size_t count)
314 {
315 	struct vt8231_data *data = dev_get_drvdata(dev);
316 	unsigned long val;
317 	int err;
318 
319 	err = kstrtoul(buf, 10, &val);
320 	if (err)
321 		return err;
322 
323 	mutex_lock(&data->update_lock);
324 	data->in_max[5] = clamp_val(((val * 958 * 34) / (10000 * 54)) + 3,
325 				    0, 255);
326 	vt8231_write_value(data, regvoltmax[5], data->in_max[5]);
327 	mutex_unlock(&data->update_lock);
328 	return count;
329 }
330 
331 #define define_voltage_sysfs(offset)				\
332 static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO,		\
333 		show_in, NULL, offset);				\
334 static SENSOR_DEVICE_ATTR(in##offset##_min, S_IRUGO | S_IWUSR,	\
335 		show_in_min, set_in_min, offset);		\
336 static SENSOR_DEVICE_ATTR(in##offset##_max, S_IRUGO | S_IWUSR,	\
337 		show_in_max, set_in_max, offset)
338 
339 define_voltage_sysfs(0);
340 define_voltage_sysfs(1);
341 define_voltage_sysfs(2);
342 define_voltage_sysfs(3);
343 define_voltage_sysfs(4);
344 
345 static DEVICE_ATTR(in5_input, S_IRUGO, show_in5, NULL);
346 static DEVICE_ATTR(in5_min, S_IRUGO | S_IWUSR, show_in5_min, set_in5_min);
347 static DEVICE_ATTR(in5_max, S_IRUGO | S_IWUSR, show_in5_max, set_in5_max);
348 
349 /* Temperatures */
350 static ssize_t show_temp0(struct device *dev, struct device_attribute *attr,
351 		char *buf)
352 {
353 	struct vt8231_data *data = vt8231_update_device(dev);
354 	return sprintf(buf, "%d\n", data->temp[0] * 250);
355 }
356 
357 static ssize_t show_temp0_max(struct device *dev, struct device_attribute *attr,
358 		char *buf)
359 {
360 	struct vt8231_data *data = vt8231_update_device(dev);
361 	return sprintf(buf, "%d\n", data->temp_max[0] * 1000);
362 }
363 
364 static ssize_t show_temp0_min(struct device *dev, struct device_attribute *attr,
365 		char *buf)
366 {
367 	struct vt8231_data *data = vt8231_update_device(dev);
368 	return sprintf(buf, "%d\n", data->temp_min[0] * 1000);
369 }
370 
371 static ssize_t set_temp0_max(struct device *dev, struct device_attribute *attr,
372 		const char *buf, size_t count)
373 {
374 	struct vt8231_data *data = dev_get_drvdata(dev);
375 	long val;
376 	int err;
377 
378 	err = kstrtol(buf, 10, &val);
379 	if (err)
380 		return err;
381 
382 	mutex_lock(&data->update_lock);
383 	data->temp_max[0] = clamp_val((val + 500) / 1000, 0, 255);
384 	vt8231_write_value(data, regtempmax[0], data->temp_max[0]);
385 	mutex_unlock(&data->update_lock);
386 	return count;
387 }
388 static ssize_t set_temp0_min(struct device *dev, struct device_attribute *attr,
389 		const char *buf, size_t count)
390 {
391 	struct vt8231_data *data = dev_get_drvdata(dev);
392 	long val;
393 	int err;
394 
395 	err = kstrtol(buf, 10, &val);
396 	if (err)
397 		return err;
398 
399 	mutex_lock(&data->update_lock);
400 	data->temp_min[0] = clamp_val((val + 500) / 1000, 0, 255);
401 	vt8231_write_value(data, regtempmin[0], data->temp_min[0]);
402 	mutex_unlock(&data->update_lock);
403 	return count;
404 }
405 
406 static ssize_t show_temp(struct device *dev, struct device_attribute *attr,
407 		char *buf)
408 {
409 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
410 	int nr = sensor_attr->index;
411 	struct vt8231_data *data = vt8231_update_device(dev);
412 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
413 }
414 
415 static ssize_t show_temp_max(struct device *dev, struct device_attribute *attr,
416 		char *buf)
417 {
418 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
419 	int nr = sensor_attr->index;
420 	struct vt8231_data *data = vt8231_update_device(dev);
421 	return sprintf(buf, "%d\n", TEMP_MAXMIN_FROM_REG(data->temp_max[nr]));
422 }
423 
424 static ssize_t show_temp_min(struct device *dev, struct device_attribute *attr,
425 		char *buf)
426 {
427 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
428 	int nr = sensor_attr->index;
429 	struct vt8231_data *data = vt8231_update_device(dev);
430 	return sprintf(buf, "%d\n", TEMP_MAXMIN_FROM_REG(data->temp_min[nr]));
431 }
432 
433 static ssize_t set_temp_max(struct device *dev, struct device_attribute *attr,
434 		const char *buf, size_t count)
435 {
436 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
437 	int nr = sensor_attr->index;
438 	struct vt8231_data *data = dev_get_drvdata(dev);
439 	long val;
440 	int err;
441 
442 	err = kstrtol(buf, 10, &val);
443 	if (err)
444 		return err;
445 
446 	mutex_lock(&data->update_lock);
447 	data->temp_max[nr] = clamp_val(TEMP_MAXMIN_TO_REG(val), 0, 255);
448 	vt8231_write_value(data, regtempmax[nr], data->temp_max[nr]);
449 	mutex_unlock(&data->update_lock);
450 	return count;
451 }
452 static ssize_t set_temp_min(struct device *dev, struct device_attribute *attr,
453 		const char *buf, size_t count)
454 {
455 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
456 	int nr = sensor_attr->index;
457 	struct vt8231_data *data = dev_get_drvdata(dev);
458 	long val;
459 	int err;
460 
461 	err = kstrtol(buf, 10, &val);
462 	if (err)
463 		return err;
464 
465 	mutex_lock(&data->update_lock);
466 	data->temp_min[nr] = clamp_val(TEMP_MAXMIN_TO_REG(val), 0, 255);
467 	vt8231_write_value(data, regtempmin[nr], data->temp_min[nr]);
468 	mutex_unlock(&data->update_lock);
469 	return count;
470 }
471 
472 /*
473  * Note that these map the Linux temperature sensor numbering (1-6) to the VIA
474  * temperature sensor numbering (0-5)
475  */
476 #define define_temperature_sysfs(offset)				\
477 static SENSOR_DEVICE_ATTR(temp##offset##_input, S_IRUGO,		\
478 		show_temp, NULL, offset - 1);				\
479 static SENSOR_DEVICE_ATTR(temp##offset##_max, S_IRUGO | S_IWUSR,	\
480 		show_temp_max, set_temp_max, offset - 1);		\
481 static SENSOR_DEVICE_ATTR(temp##offset##_max_hyst, S_IRUGO | S_IWUSR,	\
482 		show_temp_min, set_temp_min, offset - 1)
483 
484 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp0, NULL);
485 static DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, show_temp0_max, set_temp0_max);
486 static DEVICE_ATTR(temp1_max_hyst, S_IRUGO | S_IWUSR, show_temp0_min,
487 		   set_temp0_min);
488 
489 define_temperature_sysfs(2);
490 define_temperature_sysfs(3);
491 define_temperature_sysfs(4);
492 define_temperature_sysfs(5);
493 define_temperature_sysfs(6);
494 
495 /* Fans */
496 static ssize_t show_fan(struct device *dev, struct device_attribute *attr,
497 		char *buf)
498 {
499 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
500 	int nr = sensor_attr->index;
501 	struct vt8231_data *data = vt8231_update_device(dev);
502 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
503 				DIV_FROM_REG(data->fan_div[nr])));
504 }
505 
506 static ssize_t show_fan_min(struct device *dev, struct device_attribute *attr,
507 		char *buf)
508 {
509 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
510 	int nr = sensor_attr->index;
511 	struct vt8231_data *data = vt8231_update_device(dev);
512 	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
513 			DIV_FROM_REG(data->fan_div[nr])));
514 }
515 
516 static ssize_t show_fan_div(struct device *dev, struct device_attribute *attr,
517 		char *buf)
518 {
519 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
520 	int nr = sensor_attr->index;
521 	struct vt8231_data *data = vt8231_update_device(dev);
522 	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[nr]));
523 }
524 
525 static ssize_t set_fan_min(struct device *dev, struct device_attribute *attr,
526 		const char *buf, size_t count)
527 {
528 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
529 	int nr = sensor_attr->index;
530 	struct vt8231_data *data = dev_get_drvdata(dev);
531 	unsigned long val;
532 	int err;
533 
534 	err = kstrtoul(buf, 10, &val);
535 	if (err)
536 		return err;
537 
538 	mutex_lock(&data->update_lock);
539 	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
540 	vt8231_write_value(data, VT8231_REG_FAN_MIN(nr), data->fan_min[nr]);
541 	mutex_unlock(&data->update_lock);
542 	return count;
543 }
544 
545 static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr,
546 		const char *buf, size_t count)
547 {
548 	struct vt8231_data *data = dev_get_drvdata(dev);
549 	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
550 	unsigned long val;
551 	int nr = sensor_attr->index;
552 	int old = vt8231_read_value(data, VT8231_REG_FANDIV);
553 	long min = FAN_FROM_REG(data->fan_min[nr],
554 				 DIV_FROM_REG(data->fan_div[nr]));
555 	int err;
556 
557 	err = kstrtoul(buf, 10, &val);
558 	if (err)
559 		return err;
560 
561 	mutex_lock(&data->update_lock);
562 	switch (val) {
563 	case 1:
564 		data->fan_div[nr] = 0;
565 		break;
566 	case 2:
567 		data->fan_div[nr] = 1;
568 		break;
569 	case 4:
570 		data->fan_div[nr] = 2;
571 		break;
572 	case 8:
573 		data->fan_div[nr] = 3;
574 		break;
575 	default:
576 		dev_err(dev,
577 			"fan_div value %ld not supported. Choose one of 1, 2, 4 or 8!\n",
578 			val);
579 		mutex_unlock(&data->update_lock);
580 		return -EINVAL;
581 	}
582 
583 	/* Correct the fan minimum speed */
584 	data->fan_min[nr] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
585 	vt8231_write_value(data, VT8231_REG_FAN_MIN(nr), data->fan_min[nr]);
586 
587 	old = (old & 0x0f) | (data->fan_div[1] << 6) | (data->fan_div[0] << 4);
588 	vt8231_write_value(data, VT8231_REG_FANDIV, old);
589 	mutex_unlock(&data->update_lock);
590 	return count;
591 }
592 
593 
594 #define define_fan_sysfs(offset)					\
595 static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO,			\
596 		show_fan, NULL, offset - 1);				\
597 static SENSOR_DEVICE_ATTR(fan##offset##_div, S_IRUGO | S_IWUSR,		\
598 		show_fan_div, set_fan_div, offset - 1);			\
599 static SENSOR_DEVICE_ATTR(fan##offset##_min, S_IRUGO | S_IWUSR,		\
600 		show_fan_min, set_fan_min, offset - 1)
601 
602 define_fan_sysfs(1);
603 define_fan_sysfs(2);
604 
605 /* Alarms */
606 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr,
607 			   char *buf)
608 {
609 	struct vt8231_data *data = vt8231_update_device(dev);
610 	return sprintf(buf, "%d\n", data->alarms);
611 }
612 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
613 
614 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
615 			  char *buf)
616 {
617 	int bitnr = to_sensor_dev_attr(attr)->index;
618 	struct vt8231_data *data = vt8231_update_device(dev);
619 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
620 }
621 static SENSOR_DEVICE_ATTR(temp1_alarm, S_IRUGO, show_alarm, NULL, 4);
622 static SENSOR_DEVICE_ATTR(temp2_alarm, S_IRUGO, show_alarm, NULL, 11);
623 static SENSOR_DEVICE_ATTR(temp3_alarm, S_IRUGO, show_alarm, NULL, 0);
624 static SENSOR_DEVICE_ATTR(temp4_alarm, S_IRUGO, show_alarm, NULL, 1);
625 static SENSOR_DEVICE_ATTR(temp5_alarm, S_IRUGO, show_alarm, NULL, 3);
626 static SENSOR_DEVICE_ATTR(temp6_alarm, S_IRUGO, show_alarm, NULL, 8);
627 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 11);
628 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 0);
629 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 1);
630 static SENSOR_DEVICE_ATTR(in3_alarm, S_IRUGO, show_alarm, NULL, 3);
631 static SENSOR_DEVICE_ATTR(in4_alarm, S_IRUGO, show_alarm, NULL, 8);
632 static SENSOR_DEVICE_ATTR(in5_alarm, S_IRUGO, show_alarm, NULL, 2);
633 static SENSOR_DEVICE_ATTR(fan1_alarm, S_IRUGO, show_alarm, NULL, 6);
634 static SENSOR_DEVICE_ATTR(fan2_alarm, S_IRUGO, show_alarm, NULL, 7);
635 
636 static ssize_t show_name(struct device *dev, struct device_attribute
637 			 *devattr, char *buf)
638 {
639 	struct vt8231_data *data = dev_get_drvdata(dev);
640 	return sprintf(buf, "%s\n", data->name);
641 }
642 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
643 
644 static struct attribute *vt8231_attributes_temps[6][5] = {
645 	{
646 		&dev_attr_temp1_input.attr,
647 		&dev_attr_temp1_max_hyst.attr,
648 		&dev_attr_temp1_max.attr,
649 		&sensor_dev_attr_temp1_alarm.dev_attr.attr,
650 		NULL
651 	}, {
652 		&sensor_dev_attr_temp2_input.dev_attr.attr,
653 		&sensor_dev_attr_temp2_max_hyst.dev_attr.attr,
654 		&sensor_dev_attr_temp2_max.dev_attr.attr,
655 		&sensor_dev_attr_temp2_alarm.dev_attr.attr,
656 		NULL
657 	}, {
658 		&sensor_dev_attr_temp3_input.dev_attr.attr,
659 		&sensor_dev_attr_temp3_max_hyst.dev_attr.attr,
660 		&sensor_dev_attr_temp3_max.dev_attr.attr,
661 		&sensor_dev_attr_temp3_alarm.dev_attr.attr,
662 		NULL
663 	}, {
664 		&sensor_dev_attr_temp4_input.dev_attr.attr,
665 		&sensor_dev_attr_temp4_max_hyst.dev_attr.attr,
666 		&sensor_dev_attr_temp4_max.dev_attr.attr,
667 		&sensor_dev_attr_temp4_alarm.dev_attr.attr,
668 		NULL
669 	}, {
670 		&sensor_dev_attr_temp5_input.dev_attr.attr,
671 		&sensor_dev_attr_temp5_max_hyst.dev_attr.attr,
672 		&sensor_dev_attr_temp5_max.dev_attr.attr,
673 		&sensor_dev_attr_temp5_alarm.dev_attr.attr,
674 		NULL
675 	}, {
676 		&sensor_dev_attr_temp6_input.dev_attr.attr,
677 		&sensor_dev_attr_temp6_max_hyst.dev_attr.attr,
678 		&sensor_dev_attr_temp6_max.dev_attr.attr,
679 		&sensor_dev_attr_temp6_alarm.dev_attr.attr,
680 		NULL
681 	}
682 };
683 
684 static const struct attribute_group vt8231_group_temps[6] = {
685 	{ .attrs = vt8231_attributes_temps[0] },
686 	{ .attrs = vt8231_attributes_temps[1] },
687 	{ .attrs = vt8231_attributes_temps[2] },
688 	{ .attrs = vt8231_attributes_temps[3] },
689 	{ .attrs = vt8231_attributes_temps[4] },
690 	{ .attrs = vt8231_attributes_temps[5] },
691 };
692 
693 static struct attribute *vt8231_attributes_volts[6][5] = {
694 	{
695 		&sensor_dev_attr_in0_input.dev_attr.attr,
696 		&sensor_dev_attr_in0_min.dev_attr.attr,
697 		&sensor_dev_attr_in0_max.dev_attr.attr,
698 		&sensor_dev_attr_in0_alarm.dev_attr.attr,
699 		NULL
700 	}, {
701 		&sensor_dev_attr_in1_input.dev_attr.attr,
702 		&sensor_dev_attr_in1_min.dev_attr.attr,
703 		&sensor_dev_attr_in1_max.dev_attr.attr,
704 		&sensor_dev_attr_in1_alarm.dev_attr.attr,
705 		NULL
706 	}, {
707 		&sensor_dev_attr_in2_input.dev_attr.attr,
708 		&sensor_dev_attr_in2_min.dev_attr.attr,
709 		&sensor_dev_attr_in2_max.dev_attr.attr,
710 		&sensor_dev_attr_in2_alarm.dev_attr.attr,
711 		NULL
712 	}, {
713 		&sensor_dev_attr_in3_input.dev_attr.attr,
714 		&sensor_dev_attr_in3_min.dev_attr.attr,
715 		&sensor_dev_attr_in3_max.dev_attr.attr,
716 		&sensor_dev_attr_in3_alarm.dev_attr.attr,
717 		NULL
718 	}, {
719 		&sensor_dev_attr_in4_input.dev_attr.attr,
720 		&sensor_dev_attr_in4_min.dev_attr.attr,
721 		&sensor_dev_attr_in4_max.dev_attr.attr,
722 		&sensor_dev_attr_in4_alarm.dev_attr.attr,
723 		NULL
724 	}, {
725 		&dev_attr_in5_input.attr,
726 		&dev_attr_in5_min.attr,
727 		&dev_attr_in5_max.attr,
728 		&sensor_dev_attr_in5_alarm.dev_attr.attr,
729 		NULL
730 	}
731 };
732 
733 static const struct attribute_group vt8231_group_volts[6] = {
734 	{ .attrs = vt8231_attributes_volts[0] },
735 	{ .attrs = vt8231_attributes_volts[1] },
736 	{ .attrs = vt8231_attributes_volts[2] },
737 	{ .attrs = vt8231_attributes_volts[3] },
738 	{ .attrs = vt8231_attributes_volts[4] },
739 	{ .attrs = vt8231_attributes_volts[5] },
740 };
741 
742 static struct attribute *vt8231_attributes[] = {
743 	&sensor_dev_attr_fan1_input.dev_attr.attr,
744 	&sensor_dev_attr_fan2_input.dev_attr.attr,
745 	&sensor_dev_attr_fan1_min.dev_attr.attr,
746 	&sensor_dev_attr_fan2_min.dev_attr.attr,
747 	&sensor_dev_attr_fan1_div.dev_attr.attr,
748 	&sensor_dev_attr_fan2_div.dev_attr.attr,
749 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
750 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
751 	&dev_attr_alarms.attr,
752 	&dev_attr_name.attr,
753 	NULL
754 };
755 
756 static const struct attribute_group vt8231_group = {
757 	.attrs = vt8231_attributes,
758 };
759 
760 static struct platform_driver vt8231_driver = {
761 	.driver = {
762 		.name	= "vt8231",
763 	},
764 	.probe	= vt8231_probe,
765 	.remove	= vt8231_remove,
766 };
767 
768 static const struct pci_device_id vt8231_pci_ids[] = {
769 	{ PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231_4) },
770 	{ 0, }
771 };
772 
773 MODULE_DEVICE_TABLE(pci, vt8231_pci_ids);
774 
775 static int vt8231_pci_probe(struct pci_dev *dev,
776 				      const struct pci_device_id *id);
777 
778 static struct pci_driver vt8231_pci_driver = {
779 	.name		= "vt8231",
780 	.id_table	= vt8231_pci_ids,
781 	.probe		= vt8231_pci_probe,
782 };
783 
784 static int vt8231_probe(struct platform_device *pdev)
785 {
786 	struct resource *res;
787 	struct vt8231_data *data;
788 	int err = 0, i;
789 
790 	/* Reserve the ISA region */
791 	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
792 	if (!devm_request_region(&pdev->dev, res->start, VT8231_EXTENT,
793 				 vt8231_driver.driver.name)) {
794 		dev_err(&pdev->dev, "Region 0x%lx-0x%lx already in use!\n",
795 			(unsigned long)res->start, (unsigned long)res->end);
796 		return -ENODEV;
797 	}
798 
799 	data = devm_kzalloc(&pdev->dev, sizeof(struct vt8231_data), GFP_KERNEL);
800 	if (!data)
801 		return -ENOMEM;
802 
803 	platform_set_drvdata(pdev, data);
804 	data->addr = res->start;
805 	data->name = "vt8231";
806 
807 	mutex_init(&data->update_lock);
808 	vt8231_init_device(data);
809 
810 	/* Register sysfs hooks */
811 	err = sysfs_create_group(&pdev->dev.kobj, &vt8231_group);
812 	if (err)
813 		return err;
814 
815 	/* Must update device information to find out the config field */
816 	data->uch_config = vt8231_read_value(data, VT8231_REG_UCH_CONFIG);
817 
818 	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++) {
819 		if (ISTEMP(i, data->uch_config)) {
820 			err = sysfs_create_group(&pdev->dev.kobj,
821 						 &vt8231_group_temps[i]);
822 			if (err)
823 				goto exit_remove_files;
824 		}
825 	}
826 
827 	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++) {
828 		if (ISVOLT(i, data->uch_config)) {
829 			err = sysfs_create_group(&pdev->dev.kobj,
830 						 &vt8231_group_volts[i]);
831 			if (err)
832 				goto exit_remove_files;
833 		}
834 	}
835 
836 	data->hwmon_dev = hwmon_device_register(&pdev->dev);
837 	if (IS_ERR(data->hwmon_dev)) {
838 		err = PTR_ERR(data->hwmon_dev);
839 		goto exit_remove_files;
840 	}
841 	return 0;
842 
843 exit_remove_files:
844 	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++)
845 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_volts[i]);
846 
847 	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++)
848 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_temps[i]);
849 
850 	sysfs_remove_group(&pdev->dev.kobj, &vt8231_group);
851 	return err;
852 }
853 
854 static int vt8231_remove(struct platform_device *pdev)
855 {
856 	struct vt8231_data *data = platform_get_drvdata(pdev);
857 	int i;
858 
859 	hwmon_device_unregister(data->hwmon_dev);
860 
861 	for (i = 0; i < ARRAY_SIZE(vt8231_group_volts); i++)
862 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_volts[i]);
863 
864 	for (i = 0; i < ARRAY_SIZE(vt8231_group_temps); i++)
865 		sysfs_remove_group(&pdev->dev.kobj, &vt8231_group_temps[i]);
866 
867 	sysfs_remove_group(&pdev->dev.kobj, &vt8231_group);
868 
869 	return 0;
870 }
871 
872 static void vt8231_init_device(struct vt8231_data *data)
873 {
874 	vt8231_write_value(data, VT8231_REG_TEMP1_CONFIG, 0);
875 	vt8231_write_value(data, VT8231_REG_TEMP2_CONFIG, 0);
876 }
877 
878 static struct vt8231_data *vt8231_update_device(struct device *dev)
879 {
880 	struct vt8231_data *data = dev_get_drvdata(dev);
881 	int i;
882 	u16 low;
883 
884 	mutex_lock(&data->update_lock);
885 
886 	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
887 	    || !data->valid) {
888 		for (i = 0; i < 6; i++) {
889 			if (ISVOLT(i, data->uch_config)) {
890 				data->in[i] = vt8231_read_value(data,
891 						regvolt[i]);
892 				data->in_min[i] = vt8231_read_value(data,
893 						regvoltmin[i]);
894 				data->in_max[i] = vt8231_read_value(data,
895 						regvoltmax[i]);
896 			}
897 		}
898 		for (i = 0; i < 2; i++) {
899 			data->fan[i] = vt8231_read_value(data,
900 						VT8231_REG_FAN(i));
901 			data->fan_min[i] = vt8231_read_value(data,
902 						VT8231_REG_FAN_MIN(i));
903 		}
904 
905 		low = vt8231_read_value(data, VT8231_REG_TEMP_LOW01);
906 		low = (low >> 6) | ((low & 0x30) >> 2)
907 		    | (vt8231_read_value(data, VT8231_REG_TEMP_LOW25) << 4);
908 		for (i = 0; i < 6; i++) {
909 			if (ISTEMP(i, data->uch_config)) {
910 				data->temp[i] = (vt8231_read_value(data,
911 						       regtemp[i]) << 2)
912 						| ((low >> (2 * i)) & 0x03);
913 				data->temp_max[i] = vt8231_read_value(data,
914 						      regtempmax[i]);
915 				data->temp_min[i] = vt8231_read_value(data,
916 						      regtempmin[i]);
917 			}
918 		}
919 
920 		i = vt8231_read_value(data, VT8231_REG_FANDIV);
921 		data->fan_div[0] = (i >> 4) & 0x03;
922 		data->fan_div[1] = i >> 6;
923 		data->alarms = vt8231_read_value(data, VT8231_REG_ALARM1) |
924 			(vt8231_read_value(data, VT8231_REG_ALARM2) << 8);
925 
926 		/* Set alarm flags correctly */
927 		if (!data->fan[0] && data->fan_min[0])
928 			data->alarms |= 0x40;
929 		else if (data->fan[0] && !data->fan_min[0])
930 			data->alarms &= ~0x40;
931 
932 		if (!data->fan[1] && data->fan_min[1])
933 			data->alarms |= 0x80;
934 		else if (data->fan[1] && !data->fan_min[1])
935 			data->alarms &= ~0x80;
936 
937 		data->last_updated = jiffies;
938 		data->valid = 1;
939 	}
940 
941 	mutex_unlock(&data->update_lock);
942 
943 	return data;
944 }
945 
946 static int vt8231_device_add(unsigned short address)
947 {
948 	struct resource res = {
949 		.start	= address,
950 		.end	= address + VT8231_EXTENT - 1,
951 		.name	= "vt8231",
952 		.flags	= IORESOURCE_IO,
953 	};
954 	int err;
955 
956 	err = acpi_check_resource_conflict(&res);
957 	if (err)
958 		goto exit;
959 
960 	pdev = platform_device_alloc("vt8231", address);
961 	if (!pdev) {
962 		err = -ENOMEM;
963 		pr_err("Device allocation failed\n");
964 		goto exit;
965 	}
966 
967 	err = platform_device_add_resources(pdev, &res, 1);
968 	if (err) {
969 		pr_err("Device resource addition failed (%d)\n", err);
970 		goto exit_device_put;
971 	}
972 
973 	err = platform_device_add(pdev);
974 	if (err) {
975 		pr_err("Device addition failed (%d)\n", err);
976 		goto exit_device_put;
977 	}
978 
979 	return 0;
980 
981 exit_device_put:
982 	platform_device_put(pdev);
983 exit:
984 	return err;
985 }
986 
987 static int vt8231_pci_probe(struct pci_dev *dev,
988 				const struct pci_device_id *id)
989 {
990 	u16 address, val;
991 	if (force_addr) {
992 		address = force_addr & 0xff00;
993 		dev_warn(&dev->dev, "Forcing ISA address 0x%x\n",
994 			 address);
995 
996 		if (PCIBIOS_SUCCESSFUL !=
997 		    pci_write_config_word(dev, VT8231_BASE_REG, address | 1))
998 			return -ENODEV;
999 	}
1000 
1001 	if (PCIBIOS_SUCCESSFUL != pci_read_config_word(dev, VT8231_BASE_REG,
1002 							&val))
1003 		return -ENODEV;
1004 
1005 	address = val & ~(VT8231_EXTENT - 1);
1006 	if (address == 0) {
1007 		dev_err(&dev->dev, "base address not set - upgrade BIOS or use force_addr=0xaddr\n");
1008 		return -ENODEV;
1009 	}
1010 
1011 	if (PCIBIOS_SUCCESSFUL != pci_read_config_word(dev, VT8231_ENABLE_REG,
1012 							&val))
1013 		return -ENODEV;
1014 
1015 	if (!(val & 0x0001)) {
1016 		dev_warn(&dev->dev, "enabling sensors\n");
1017 		if (PCIBIOS_SUCCESSFUL !=
1018 			pci_write_config_word(dev, VT8231_ENABLE_REG,
1019 							val | 0x0001))
1020 			return -ENODEV;
1021 	}
1022 
1023 	if (platform_driver_register(&vt8231_driver))
1024 		goto exit;
1025 
1026 	/* Sets global pdev as a side effect */
1027 	if (vt8231_device_add(address))
1028 		goto exit_unregister;
1029 
1030 	/*
1031 	 * Always return failure here.  This is to allow other drivers to bind
1032 	 * to this pci device.  We don't really want to have control over the
1033 	 * pci device, we only wanted to read as few register values from it.
1034 	 */
1035 
1036 	/*
1037 	 * We do, however, mark ourselves as using the PCI device to stop it
1038 	 * getting unloaded.
1039 	 */
1040 	s_bridge = pci_dev_get(dev);
1041 	return -ENODEV;
1042 
1043 exit_unregister:
1044 	platform_driver_unregister(&vt8231_driver);
1045 exit:
1046 	return -ENODEV;
1047 }
1048 
1049 static int __init sm_vt8231_init(void)
1050 {
1051 	return pci_register_driver(&vt8231_pci_driver);
1052 }
1053 
1054 static void __exit sm_vt8231_exit(void)
1055 {
1056 	pci_unregister_driver(&vt8231_pci_driver);
1057 	if (s_bridge != NULL) {
1058 		platform_device_unregister(pdev);
1059 		platform_driver_unregister(&vt8231_driver);
1060 		pci_dev_put(s_bridge);
1061 		s_bridge = NULL;
1062 	}
1063 }
1064 
1065 MODULE_AUTHOR("Roger Lucas <vt8231@hiddenengine.co.uk>");
1066 MODULE_DESCRIPTION("VT8231 sensors");
1067 MODULE_LICENSE("GPL");
1068 
1069 module_init(sm_vt8231_init);
1070 module_exit(sm_vt8231_exit);
1071