1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * lm78.c - Part of lm_sensors, Linux kernel modules for hardware
4 * monitoring
5 * Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl>
6 * Copyright (c) 2007, 2011 Jean Delvare <jdelvare@suse.de>
7 */
8
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/slab.h>
14 #include <linux/jiffies.h>
15 #include <linux/i2c.h>
16 #include <linux/hwmon.h>
17 #include <linux/hwmon-vid.h>
18 #include <linux/hwmon-sysfs.h>
19 #include <linux/err.h>
20 #include <linux/mutex.h>
21
22 #ifdef CONFIG_ISA
23 #include <linux/platform_device.h>
24 #include <linux/ioport.h>
25 #include <linux/io.h>
26 #endif
27
28 /* Addresses to scan */
29 static const unsigned short normal_i2c[] = { 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
30 0x2e, 0x2f, I2C_CLIENT_END };
31 enum chips { lm78, lm79 };
32
33 /* Many LM78 constants specified below */
34
35 /* Length of ISA address segment */
36 #define LM78_EXTENT 8
37
38 /* Where are the ISA address/data registers relative to the base address */
39 #define LM78_ADDR_REG_OFFSET 5
40 #define LM78_DATA_REG_OFFSET 6
41
42 /* The LM78 registers */
43 #define LM78_REG_IN_MAX(nr) (0x2b + (nr) * 2)
44 #define LM78_REG_IN_MIN(nr) (0x2c + (nr) * 2)
45 #define LM78_REG_IN(nr) (0x20 + (nr))
46
47 #define LM78_REG_FAN_MIN(nr) (0x3b + (nr))
48 #define LM78_REG_FAN(nr) (0x28 + (nr))
49
50 #define LM78_REG_TEMP 0x27
51 #define LM78_REG_TEMP_OVER 0x39
52 #define LM78_REG_TEMP_HYST 0x3a
53
54 #define LM78_REG_ALARM1 0x41
55 #define LM78_REG_ALARM2 0x42
56
57 #define LM78_REG_VID_FANDIV 0x47
58
59 #define LM78_REG_CONFIG 0x40
60 #define LM78_REG_CHIPID 0x49
61 #define LM78_REG_I2C_ADDR 0x48
62
63 /*
64 * Conversions. Rounding and limit checking is only done on the TO_REG
65 * variants.
66 */
67
68 /*
69 * IN: mV (0V to 4.08V)
70 * REG: 16mV/bit
71 */
IN_TO_REG(unsigned long val)72 static inline u8 IN_TO_REG(unsigned long val)
73 {
74 unsigned long nval = clamp_val(val, 0, 4080);
75 return (nval + 8) / 16;
76 }
77 #define IN_FROM_REG(val) ((val) * 16)
78
FAN_TO_REG(long rpm,int div)79 static inline u8 FAN_TO_REG(long rpm, int div)
80 {
81 if (rpm <= 0)
82 return 255;
83 if (rpm > 1350000)
84 return 1;
85 return clamp_val((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
86 }
87
FAN_FROM_REG(u8 val,int div)88 static inline int FAN_FROM_REG(u8 val, int div)
89 {
90 return val == 0 ? -1 : val == 255 ? 0 : 1350000 / (val * div);
91 }
92
93 /*
94 * TEMP: mC (-128C to +127C)
95 * REG: 1C/bit, two's complement
96 */
TEMP_TO_REG(long val)97 static inline s8 TEMP_TO_REG(long val)
98 {
99 int nval = clamp_val(val, -128000, 127000) ;
100 return nval < 0 ? (nval - 500) / 1000 : (nval + 500) / 1000;
101 }
102
TEMP_FROM_REG(s8 val)103 static inline int TEMP_FROM_REG(s8 val)
104 {
105 return val * 1000;
106 }
107
108 #define DIV_FROM_REG(val) (1 << (val))
109
110 struct lm78_data {
111 struct i2c_client *client;
112 struct mutex lock;
113 enum chips type;
114
115 /* For ISA device only */
116 const char *name;
117 int isa_addr;
118
119 struct mutex update_lock;
120 bool valid; /* true if following fields are valid */
121 unsigned long last_updated; /* In jiffies */
122
123 u8 in[7]; /* Register value */
124 u8 in_max[7]; /* Register value */
125 u8 in_min[7]; /* Register value */
126 u8 fan[3]; /* Register value */
127 u8 fan_min[3]; /* Register value */
128 s8 temp; /* Register value */
129 s8 temp_over; /* Register value */
130 s8 temp_hyst; /* Register value */
131 u8 fan_div[3]; /* Register encoding, shifted right */
132 u8 vid; /* Register encoding, combined */
133 u16 alarms; /* Register encoding, combined */
134 };
135
136 static int lm78_read_value(struct lm78_data *data, u8 reg);
137 static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value);
138 static struct lm78_data *lm78_update_device(struct device *dev);
139 static void lm78_init_device(struct lm78_data *data);
140
141 /* 7 Voltages */
in_show(struct device * dev,struct device_attribute * da,char * buf)142 static ssize_t in_show(struct device *dev, struct device_attribute *da,
143 char *buf)
144 {
145 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
146 struct lm78_data *data = lm78_update_device(dev);
147 return sprintf(buf, "%d\n", IN_FROM_REG(data->in[attr->index]));
148 }
149
in_min_show(struct device * dev,struct device_attribute * da,char * buf)150 static ssize_t in_min_show(struct device *dev, struct device_attribute *da,
151 char *buf)
152 {
153 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
154 struct lm78_data *data = lm78_update_device(dev);
155 return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[attr->index]));
156 }
157
in_max_show(struct device * dev,struct device_attribute * da,char * buf)158 static ssize_t in_max_show(struct device *dev, struct device_attribute *da,
159 char *buf)
160 {
161 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
162 struct lm78_data *data = lm78_update_device(dev);
163 return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[attr->index]));
164 }
165
in_min_store(struct device * dev,struct device_attribute * da,const char * buf,size_t count)166 static ssize_t in_min_store(struct device *dev, struct device_attribute *da,
167 const char *buf, size_t count)
168 {
169 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
170 struct lm78_data *data = dev_get_drvdata(dev);
171 int nr = attr->index;
172 unsigned long val;
173 int err;
174
175 err = kstrtoul(buf, 10, &val);
176 if (err)
177 return err;
178
179 mutex_lock(&data->update_lock);
180 data->in_min[nr] = IN_TO_REG(val);
181 lm78_write_value(data, LM78_REG_IN_MIN(nr), data->in_min[nr]);
182 mutex_unlock(&data->update_lock);
183 return count;
184 }
185
in_max_store(struct device * dev,struct device_attribute * da,const char * buf,size_t count)186 static ssize_t in_max_store(struct device *dev, struct device_attribute *da,
187 const char *buf, size_t count)
188 {
189 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
190 struct lm78_data *data = dev_get_drvdata(dev);
191 int nr = attr->index;
192 unsigned long val;
193 int err;
194
195 err = kstrtoul(buf, 10, &val);
196 if (err)
197 return err;
198
199 mutex_lock(&data->update_lock);
200 data->in_max[nr] = IN_TO_REG(val);
201 lm78_write_value(data, LM78_REG_IN_MAX(nr), data->in_max[nr]);
202 mutex_unlock(&data->update_lock);
203 return count;
204 }
205
206 static SENSOR_DEVICE_ATTR_RO(in0_input, in, 0);
207 static SENSOR_DEVICE_ATTR_RW(in0_min, in_min, 0);
208 static SENSOR_DEVICE_ATTR_RW(in0_max, in_max, 0);
209 static SENSOR_DEVICE_ATTR_RO(in1_input, in, 1);
210 static SENSOR_DEVICE_ATTR_RW(in1_min, in_min, 1);
211 static SENSOR_DEVICE_ATTR_RW(in1_max, in_max, 1);
212 static SENSOR_DEVICE_ATTR_RO(in2_input, in, 2);
213 static SENSOR_DEVICE_ATTR_RW(in2_min, in_min, 2);
214 static SENSOR_DEVICE_ATTR_RW(in2_max, in_max, 2);
215 static SENSOR_DEVICE_ATTR_RO(in3_input, in, 3);
216 static SENSOR_DEVICE_ATTR_RW(in3_min, in_min, 3);
217 static SENSOR_DEVICE_ATTR_RW(in3_max, in_max, 3);
218 static SENSOR_DEVICE_ATTR_RO(in4_input, in, 4);
219 static SENSOR_DEVICE_ATTR_RW(in4_min, in_min, 4);
220 static SENSOR_DEVICE_ATTR_RW(in4_max, in_max, 4);
221 static SENSOR_DEVICE_ATTR_RO(in5_input, in, 5);
222 static SENSOR_DEVICE_ATTR_RW(in5_min, in_min, 5);
223 static SENSOR_DEVICE_ATTR_RW(in5_max, in_max, 5);
224 static SENSOR_DEVICE_ATTR_RO(in6_input, in, 6);
225 static SENSOR_DEVICE_ATTR_RW(in6_min, in_min, 6);
226 static SENSOR_DEVICE_ATTR_RW(in6_max, in_max, 6);
227
228 /* Temperature */
temp1_input_show(struct device * dev,struct device_attribute * da,char * buf)229 static ssize_t temp1_input_show(struct device *dev,
230 struct device_attribute *da, char *buf)
231 {
232 struct lm78_data *data = lm78_update_device(dev);
233 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp));
234 }
235
temp1_max_show(struct device * dev,struct device_attribute * da,char * buf)236 static ssize_t temp1_max_show(struct device *dev, struct device_attribute *da,
237 char *buf)
238 {
239 struct lm78_data *data = lm78_update_device(dev);
240 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_over));
241 }
242
temp1_max_store(struct device * dev,struct device_attribute * da,const char * buf,size_t count)243 static ssize_t temp1_max_store(struct device *dev,
244 struct device_attribute *da, const char *buf,
245 size_t count)
246 {
247 struct lm78_data *data = dev_get_drvdata(dev);
248 long val;
249 int err;
250
251 err = kstrtol(buf, 10, &val);
252 if (err)
253 return err;
254
255 mutex_lock(&data->update_lock);
256 data->temp_over = TEMP_TO_REG(val);
257 lm78_write_value(data, LM78_REG_TEMP_OVER, data->temp_over);
258 mutex_unlock(&data->update_lock);
259 return count;
260 }
261
temp1_max_hyst_show(struct device * dev,struct device_attribute * da,char * buf)262 static ssize_t temp1_max_hyst_show(struct device *dev,
263 struct device_attribute *da, char *buf)
264 {
265 struct lm78_data *data = lm78_update_device(dev);
266 return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_hyst));
267 }
268
temp1_max_hyst_store(struct device * dev,struct device_attribute * da,const char * buf,size_t count)269 static ssize_t temp1_max_hyst_store(struct device *dev,
270 struct device_attribute *da,
271 const char *buf, size_t count)
272 {
273 struct lm78_data *data = dev_get_drvdata(dev);
274 long val;
275 int err;
276
277 err = kstrtol(buf, 10, &val);
278 if (err)
279 return err;
280
281 mutex_lock(&data->update_lock);
282 data->temp_hyst = TEMP_TO_REG(val);
283 lm78_write_value(data, LM78_REG_TEMP_HYST, data->temp_hyst);
284 mutex_unlock(&data->update_lock);
285 return count;
286 }
287
288 static DEVICE_ATTR_RO(temp1_input);
289 static DEVICE_ATTR_RW(temp1_max);
290 static DEVICE_ATTR_RW(temp1_max_hyst);
291
292 /* 3 Fans */
fan_show(struct device * dev,struct device_attribute * da,char * buf)293 static ssize_t fan_show(struct device *dev, struct device_attribute *da,
294 char *buf)
295 {
296 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
297 struct lm78_data *data = lm78_update_device(dev);
298 int nr = attr->index;
299 return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
300 DIV_FROM_REG(data->fan_div[nr])));
301 }
302
fan_min_show(struct device * dev,struct device_attribute * da,char * buf)303 static ssize_t fan_min_show(struct device *dev, struct device_attribute *da,
304 char *buf)
305 {
306 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
307 struct lm78_data *data = lm78_update_device(dev);
308 int nr = attr->index;
309 return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
310 DIV_FROM_REG(data->fan_div[nr])));
311 }
312
fan_min_store(struct device * dev,struct device_attribute * da,const char * buf,size_t count)313 static ssize_t fan_min_store(struct device *dev, struct device_attribute *da,
314 const char *buf, size_t count)
315 {
316 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
317 struct lm78_data *data = dev_get_drvdata(dev);
318 int nr = attr->index;
319 unsigned long val;
320 int err;
321
322 err = kstrtoul(buf, 10, &val);
323 if (err)
324 return err;
325
326 mutex_lock(&data->update_lock);
327 data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
328 lm78_write_value(data, LM78_REG_FAN_MIN(nr), data->fan_min[nr]);
329 mutex_unlock(&data->update_lock);
330 return count;
331 }
332
fan_div_show(struct device * dev,struct device_attribute * da,char * buf)333 static ssize_t fan_div_show(struct device *dev, struct device_attribute *da,
334 char *buf)
335 {
336 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
337 struct lm78_data *data = lm78_update_device(dev);
338 return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[attr->index]));
339 }
340
341 /*
342 * Note: we save and restore the fan minimum here, because its value is
343 * determined in part by the fan divisor. This follows the principle of
344 * least surprise; the user doesn't expect the fan minimum to change just
345 * because the divisor changed.
346 */
fan_div_store(struct device * dev,struct device_attribute * da,const char * buf,size_t count)347 static ssize_t fan_div_store(struct device *dev, struct device_attribute *da,
348 const char *buf, size_t count)
349 {
350 struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
351 struct lm78_data *data = dev_get_drvdata(dev);
352 int nr = attr->index;
353 unsigned long min;
354 u8 reg;
355 unsigned long val;
356 int err;
357
358 err = kstrtoul(buf, 10, &val);
359 if (err)
360 return err;
361
362 mutex_lock(&data->update_lock);
363 min = FAN_FROM_REG(data->fan_min[nr],
364 DIV_FROM_REG(data->fan_div[nr]));
365
366 switch (val) {
367 case 1:
368 data->fan_div[nr] = 0;
369 break;
370 case 2:
371 data->fan_div[nr] = 1;
372 break;
373 case 4:
374 data->fan_div[nr] = 2;
375 break;
376 case 8:
377 data->fan_div[nr] = 3;
378 break;
379 default:
380 dev_err(dev,
381 "fan_div value %ld not supported. Choose one of 1, 2, 4 or 8!\n",
382 val);
383 mutex_unlock(&data->update_lock);
384 return -EINVAL;
385 }
386
387 reg = lm78_read_value(data, LM78_REG_VID_FANDIV);
388 switch (nr) {
389 case 0:
390 reg = (reg & 0xcf) | (data->fan_div[nr] << 4);
391 break;
392 case 1:
393 reg = (reg & 0x3f) | (data->fan_div[nr] << 6);
394 break;
395 }
396 lm78_write_value(data, LM78_REG_VID_FANDIV, reg);
397
398 data->fan_min[nr] =
399 FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
400 lm78_write_value(data, LM78_REG_FAN_MIN(nr), data->fan_min[nr]);
401 mutex_unlock(&data->update_lock);
402
403 return count;
404 }
405
406 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0);
407 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
408 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1);
409 static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
410 static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 2);
411 static SENSOR_DEVICE_ATTR_RW(fan3_min, fan_min, 2);
412
413 /* Fan 3 divisor is locked in H/W */
414 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
415 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
416 static SENSOR_DEVICE_ATTR_RO(fan3_div, fan_div, 2);
417
418 /* VID */
cpu0_vid_show(struct device * dev,struct device_attribute * da,char * buf)419 static ssize_t cpu0_vid_show(struct device *dev, struct device_attribute *da,
420 char *buf)
421 {
422 struct lm78_data *data = lm78_update_device(dev);
423 return sprintf(buf, "%d\n", vid_from_reg(data->vid, 82));
424 }
425 static DEVICE_ATTR_RO(cpu0_vid);
426
427 /* Alarms */
alarms_show(struct device * dev,struct device_attribute * da,char * buf)428 static ssize_t alarms_show(struct device *dev, struct device_attribute *da,
429 char *buf)
430 {
431 struct lm78_data *data = lm78_update_device(dev);
432 return sprintf(buf, "%u\n", data->alarms);
433 }
434 static DEVICE_ATTR_RO(alarms);
435
alarm_show(struct device * dev,struct device_attribute * da,char * buf)436 static ssize_t alarm_show(struct device *dev, struct device_attribute *da,
437 char *buf)
438 {
439 struct lm78_data *data = lm78_update_device(dev);
440 int nr = to_sensor_dev_attr(da)->index;
441 return sprintf(buf, "%u\n", (data->alarms >> nr) & 1);
442 }
443 static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0);
444 static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 1);
445 static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 2);
446 static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 3);
447 static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 8);
448 static SENSOR_DEVICE_ATTR_RO(in5_alarm, alarm, 9);
449 static SENSOR_DEVICE_ATTR_RO(in6_alarm, alarm, 10);
450 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, alarm, 6);
451 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, alarm, 7);
452 static SENSOR_DEVICE_ATTR_RO(fan3_alarm, alarm, 11);
453 static SENSOR_DEVICE_ATTR_RO(temp1_alarm, alarm, 4);
454
455 static struct attribute *lm78_attrs[] = {
456 &sensor_dev_attr_in0_input.dev_attr.attr,
457 &sensor_dev_attr_in0_min.dev_attr.attr,
458 &sensor_dev_attr_in0_max.dev_attr.attr,
459 &sensor_dev_attr_in0_alarm.dev_attr.attr,
460 &sensor_dev_attr_in1_input.dev_attr.attr,
461 &sensor_dev_attr_in1_min.dev_attr.attr,
462 &sensor_dev_attr_in1_max.dev_attr.attr,
463 &sensor_dev_attr_in1_alarm.dev_attr.attr,
464 &sensor_dev_attr_in2_input.dev_attr.attr,
465 &sensor_dev_attr_in2_min.dev_attr.attr,
466 &sensor_dev_attr_in2_max.dev_attr.attr,
467 &sensor_dev_attr_in2_alarm.dev_attr.attr,
468 &sensor_dev_attr_in3_input.dev_attr.attr,
469 &sensor_dev_attr_in3_min.dev_attr.attr,
470 &sensor_dev_attr_in3_max.dev_attr.attr,
471 &sensor_dev_attr_in3_alarm.dev_attr.attr,
472 &sensor_dev_attr_in4_input.dev_attr.attr,
473 &sensor_dev_attr_in4_min.dev_attr.attr,
474 &sensor_dev_attr_in4_max.dev_attr.attr,
475 &sensor_dev_attr_in4_alarm.dev_attr.attr,
476 &sensor_dev_attr_in5_input.dev_attr.attr,
477 &sensor_dev_attr_in5_min.dev_attr.attr,
478 &sensor_dev_attr_in5_max.dev_attr.attr,
479 &sensor_dev_attr_in5_alarm.dev_attr.attr,
480 &sensor_dev_attr_in6_input.dev_attr.attr,
481 &sensor_dev_attr_in6_min.dev_attr.attr,
482 &sensor_dev_attr_in6_max.dev_attr.attr,
483 &sensor_dev_attr_in6_alarm.dev_attr.attr,
484 &dev_attr_temp1_input.attr,
485 &dev_attr_temp1_max.attr,
486 &dev_attr_temp1_max_hyst.attr,
487 &sensor_dev_attr_temp1_alarm.dev_attr.attr,
488 &sensor_dev_attr_fan1_input.dev_attr.attr,
489 &sensor_dev_attr_fan1_min.dev_attr.attr,
490 &sensor_dev_attr_fan1_div.dev_attr.attr,
491 &sensor_dev_attr_fan1_alarm.dev_attr.attr,
492 &sensor_dev_attr_fan2_input.dev_attr.attr,
493 &sensor_dev_attr_fan2_min.dev_attr.attr,
494 &sensor_dev_attr_fan2_div.dev_attr.attr,
495 &sensor_dev_attr_fan2_alarm.dev_attr.attr,
496 &sensor_dev_attr_fan3_input.dev_attr.attr,
497 &sensor_dev_attr_fan3_min.dev_attr.attr,
498 &sensor_dev_attr_fan3_div.dev_attr.attr,
499 &sensor_dev_attr_fan3_alarm.dev_attr.attr,
500 &dev_attr_alarms.attr,
501 &dev_attr_cpu0_vid.attr,
502
503 NULL
504 };
505
506 ATTRIBUTE_GROUPS(lm78);
507
508 /*
509 * ISA related code
510 */
511 #ifdef CONFIG_ISA
512
513 /* ISA device, if found */
514 static struct platform_device *pdev;
515
516 static unsigned short isa_address = 0x290;
517
lm78_data_if_isa(void)518 static struct lm78_data *lm78_data_if_isa(void)
519 {
520 return pdev ? platform_get_drvdata(pdev) : NULL;
521 }
522
523 /* Returns 1 if the I2C chip appears to be an alias of the ISA chip */
lm78_alias_detect(struct i2c_client * client,u8 chipid)524 static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
525 {
526 struct lm78_data *isa;
527 int i;
528
529 if (!pdev) /* No ISA chip */
530 return 0;
531 isa = platform_get_drvdata(pdev);
532
533 if (lm78_read_value(isa, LM78_REG_I2C_ADDR) != client->addr)
534 return 0; /* Address doesn't match */
535 if ((lm78_read_value(isa, LM78_REG_CHIPID) & 0xfe) != (chipid & 0xfe))
536 return 0; /* Chip type doesn't match */
537
538 /*
539 * We compare all the limit registers, the config register and the
540 * interrupt mask registers
541 */
542 for (i = 0x2b; i <= 0x3d; i++) {
543 if (lm78_read_value(isa, i) !=
544 i2c_smbus_read_byte_data(client, i))
545 return 0;
546 }
547 if (lm78_read_value(isa, LM78_REG_CONFIG) !=
548 i2c_smbus_read_byte_data(client, LM78_REG_CONFIG))
549 return 0;
550 for (i = 0x43; i <= 0x46; i++) {
551 if (lm78_read_value(isa, i) !=
552 i2c_smbus_read_byte_data(client, i))
553 return 0;
554 }
555
556 return 1;
557 }
558 #else /* !CONFIG_ISA */
559
lm78_alias_detect(struct i2c_client * client,u8 chipid)560 static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
561 {
562 return 0;
563 }
564
lm78_data_if_isa(void)565 static struct lm78_data *lm78_data_if_isa(void)
566 {
567 return NULL;
568 }
569 #endif /* CONFIG_ISA */
570
lm78_i2c_detect(struct i2c_client * client,struct i2c_board_info * info)571 static int lm78_i2c_detect(struct i2c_client *client,
572 struct i2c_board_info *info)
573 {
574 int i;
575 struct lm78_data *isa = lm78_data_if_isa();
576 const char *client_name;
577 struct i2c_adapter *adapter = client->adapter;
578 int address = client->addr;
579
580 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
581 return -ENODEV;
582
583 /*
584 * We block updates of the ISA device to minimize the risk of
585 * concurrent access to the same LM78 chip through different
586 * interfaces.
587 */
588 if (isa)
589 mutex_lock(&isa->update_lock);
590
591 if ((i2c_smbus_read_byte_data(client, LM78_REG_CONFIG) & 0x80)
592 || i2c_smbus_read_byte_data(client, LM78_REG_I2C_ADDR) != address)
593 goto err_nodev;
594
595 /* Explicitly prevent the misdetection of Winbond chips */
596 i = i2c_smbus_read_byte_data(client, 0x4f);
597 if (i == 0xa3 || i == 0x5c)
598 goto err_nodev;
599
600 /* Determine the chip type. */
601 i = i2c_smbus_read_byte_data(client, LM78_REG_CHIPID);
602 if (i == 0x00 || i == 0x20 /* LM78 */
603 || i == 0x40) /* LM78-J */
604 client_name = "lm78";
605 else if ((i & 0xfe) == 0xc0)
606 client_name = "lm79";
607 else
608 goto err_nodev;
609
610 if (lm78_alias_detect(client, i)) {
611 dev_dbg(&adapter->dev,
612 "Device at 0x%02x appears to be the same as ISA device\n",
613 address);
614 goto err_nodev;
615 }
616
617 if (isa)
618 mutex_unlock(&isa->update_lock);
619
620 strscpy(info->type, client_name, I2C_NAME_SIZE);
621
622 return 0;
623
624 err_nodev:
625 if (isa)
626 mutex_unlock(&isa->update_lock);
627 return -ENODEV;
628 }
629
lm78_i2c_probe(struct i2c_client * client)630 static int lm78_i2c_probe(struct i2c_client *client)
631 {
632 struct device *dev = &client->dev;
633 struct device *hwmon_dev;
634 struct lm78_data *data;
635
636 data = devm_kzalloc(dev, sizeof(struct lm78_data), GFP_KERNEL);
637 if (!data)
638 return -ENOMEM;
639
640 data->client = client;
641 data->type = (uintptr_t)i2c_get_match_data(client);
642
643 /* Initialize the LM78 chip */
644 lm78_init_device(data);
645
646 hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
647 data, lm78_groups);
648 return PTR_ERR_OR_ZERO(hwmon_dev);
649 }
650
651 static const struct i2c_device_id lm78_i2c_id[] = {
652 { "lm78", lm78 },
653 { "lm79", lm79 },
654 { }
655 };
656 MODULE_DEVICE_TABLE(i2c, lm78_i2c_id);
657
658 static struct i2c_driver lm78_driver = {
659 .class = I2C_CLASS_HWMON,
660 .driver = {
661 .name = "lm78",
662 },
663 .probe = lm78_i2c_probe,
664 .id_table = lm78_i2c_id,
665 .detect = lm78_i2c_detect,
666 .address_list = normal_i2c,
667 };
668
669 /*
670 * The SMBus locks itself, but ISA access must be locked explicitly!
671 * We don't want to lock the whole ISA bus, so we lock each client
672 * separately.
673 * We ignore the LM78 BUSY flag at this moment - it could lead to deadlocks,
674 * would slow down the LM78 access and should not be necessary.
675 */
lm78_read_value(struct lm78_data * data,u8 reg)676 static int lm78_read_value(struct lm78_data *data, u8 reg)
677 {
678 struct i2c_client *client = data->client;
679
680 #ifdef CONFIG_ISA
681 if (!client) { /* ISA device */
682 int res;
683 mutex_lock(&data->lock);
684 outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
685 res = inb_p(data->isa_addr + LM78_DATA_REG_OFFSET);
686 mutex_unlock(&data->lock);
687 return res;
688 } else
689 #endif
690 return i2c_smbus_read_byte_data(client, reg);
691 }
692
lm78_write_value(struct lm78_data * data,u8 reg,u8 value)693 static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value)
694 {
695 struct i2c_client *client = data->client;
696
697 #ifdef CONFIG_ISA
698 if (!client) { /* ISA device */
699 mutex_lock(&data->lock);
700 outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
701 outb_p(value, data->isa_addr + LM78_DATA_REG_OFFSET);
702 mutex_unlock(&data->lock);
703 return 0;
704 } else
705 #endif
706 return i2c_smbus_write_byte_data(client, reg, value);
707 }
708
lm78_init_device(struct lm78_data * data)709 static void lm78_init_device(struct lm78_data *data)
710 {
711 u8 config;
712 int i;
713
714 /* Start monitoring */
715 config = lm78_read_value(data, LM78_REG_CONFIG);
716 if ((config & 0x09) != 0x01)
717 lm78_write_value(data, LM78_REG_CONFIG,
718 (config & 0xf7) | 0x01);
719
720 /* A few vars need to be filled upon startup */
721 for (i = 0; i < 3; i++) {
722 data->fan_min[i] = lm78_read_value(data,
723 LM78_REG_FAN_MIN(i));
724 }
725
726 mutex_init(&data->update_lock);
727 }
728
lm78_update_device(struct device * dev)729 static struct lm78_data *lm78_update_device(struct device *dev)
730 {
731 struct lm78_data *data = dev_get_drvdata(dev);
732 int i;
733
734 mutex_lock(&data->update_lock);
735
736 if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
737 || !data->valid) {
738
739 dev_dbg(dev, "Starting lm78 update\n");
740
741 for (i = 0; i <= 6; i++) {
742 data->in[i] =
743 lm78_read_value(data, LM78_REG_IN(i));
744 data->in_min[i] =
745 lm78_read_value(data, LM78_REG_IN_MIN(i));
746 data->in_max[i] =
747 lm78_read_value(data, LM78_REG_IN_MAX(i));
748 }
749 for (i = 0; i < 3; i++) {
750 data->fan[i] =
751 lm78_read_value(data, LM78_REG_FAN(i));
752 data->fan_min[i] =
753 lm78_read_value(data, LM78_REG_FAN_MIN(i));
754 }
755 data->temp = lm78_read_value(data, LM78_REG_TEMP);
756 data->temp_over =
757 lm78_read_value(data, LM78_REG_TEMP_OVER);
758 data->temp_hyst =
759 lm78_read_value(data, LM78_REG_TEMP_HYST);
760 i = lm78_read_value(data, LM78_REG_VID_FANDIV);
761 data->vid = i & 0x0f;
762 if (data->type == lm79)
763 data->vid |=
764 (lm78_read_value(data, LM78_REG_CHIPID) &
765 0x01) << 4;
766 else
767 data->vid |= 0x10;
768 data->fan_div[0] = (i >> 4) & 0x03;
769 data->fan_div[1] = i >> 6;
770 data->alarms = lm78_read_value(data, LM78_REG_ALARM1) +
771 (lm78_read_value(data, LM78_REG_ALARM2) << 8);
772 data->last_updated = jiffies;
773 data->valid = true;
774
775 data->fan_div[2] = 1;
776 }
777
778 mutex_unlock(&data->update_lock);
779
780 return data;
781 }
782
783 #ifdef CONFIG_ISA
lm78_isa_probe(struct platform_device * pdev)784 static int lm78_isa_probe(struct platform_device *pdev)
785 {
786 struct device *dev = &pdev->dev;
787 struct device *hwmon_dev;
788 struct lm78_data *data;
789 struct resource *res;
790
791 /* Reserve the ISA region */
792 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
793 if (!devm_request_region(dev, res->start + LM78_ADDR_REG_OFFSET,
794 2, "lm78"))
795 return -EBUSY;
796
797 data = devm_kzalloc(dev, sizeof(struct lm78_data), GFP_KERNEL);
798 if (!data)
799 return -ENOMEM;
800
801 mutex_init(&data->lock);
802 data->isa_addr = res->start;
803 platform_set_drvdata(pdev, data);
804
805 if (lm78_read_value(data, LM78_REG_CHIPID) & 0x80) {
806 data->type = lm79;
807 data->name = "lm79";
808 } else {
809 data->type = lm78;
810 data->name = "lm78";
811 }
812
813 /* Initialize the LM78 chip */
814 lm78_init_device(data);
815
816 hwmon_dev = devm_hwmon_device_register_with_groups(dev, data->name,
817 data, lm78_groups);
818 return PTR_ERR_OR_ZERO(hwmon_dev);
819 }
820
821 static struct platform_driver lm78_isa_driver = {
822 .driver = {
823 .name = "lm78",
824 },
825 .probe = lm78_isa_probe,
826 };
827
828 /* return 1 if a supported chip is found, 0 otherwise */
lm78_isa_found(unsigned short address)829 static int __init lm78_isa_found(unsigned short address)
830 {
831 int val, save, found = 0;
832 int port;
833
834 /*
835 * Some boards declare base+0 to base+7 as a PNP device, some base+4
836 * to base+7 and some base+5 to base+6. So we better request each port
837 * individually for the probing phase.
838 */
839 for (port = address; port < address + LM78_EXTENT; port++) {
840 if (!request_region(port, 1, "lm78")) {
841 pr_debug("Failed to request port 0x%x\n", port);
842 goto release;
843 }
844 }
845
846 #define REALLY_SLOW_IO
847 /*
848 * We need the timeouts for at least some LM78-like
849 * chips. But only if we read 'undefined' registers.
850 */
851 val = inb_p(address + 1);
852 if (inb_p(address + 2) != val
853 || inb_p(address + 3) != val
854 || inb_p(address + 7) != val)
855 goto release;
856 #undef REALLY_SLOW_IO
857
858 /*
859 * We should be able to change the 7 LSB of the address port. The
860 * MSB (busy flag) should be clear initially, set after the write.
861 */
862 save = inb_p(address + LM78_ADDR_REG_OFFSET);
863 if (save & 0x80)
864 goto release;
865 val = ~save & 0x7f;
866 outb_p(val, address + LM78_ADDR_REG_OFFSET);
867 if (inb_p(address + LM78_ADDR_REG_OFFSET) != (val | 0x80)) {
868 outb_p(save, address + LM78_ADDR_REG_OFFSET);
869 goto release;
870 }
871
872 /* We found a device, now see if it could be an LM78 */
873 outb_p(LM78_REG_CONFIG, address + LM78_ADDR_REG_OFFSET);
874 val = inb_p(address + LM78_DATA_REG_OFFSET);
875 if (val & 0x80)
876 goto release;
877 outb_p(LM78_REG_I2C_ADDR, address + LM78_ADDR_REG_OFFSET);
878 val = inb_p(address + LM78_DATA_REG_OFFSET);
879 if (val < 0x03 || val > 0x77) /* Not a valid I2C address */
880 goto release;
881
882 /* The busy flag should be clear again */
883 if (inb_p(address + LM78_ADDR_REG_OFFSET) & 0x80)
884 goto release;
885
886 /* Explicitly prevent the misdetection of Winbond chips */
887 outb_p(0x4f, address + LM78_ADDR_REG_OFFSET);
888 val = inb_p(address + LM78_DATA_REG_OFFSET);
889 if (val == 0xa3 || val == 0x5c)
890 goto release;
891
892 /* Explicitly prevent the misdetection of ITE chips */
893 outb_p(0x58, address + LM78_ADDR_REG_OFFSET);
894 val = inb_p(address + LM78_DATA_REG_OFFSET);
895 if (val == 0x90)
896 goto release;
897
898 /* Determine the chip type */
899 outb_p(LM78_REG_CHIPID, address + LM78_ADDR_REG_OFFSET);
900 val = inb_p(address + LM78_DATA_REG_OFFSET);
901 if (val == 0x00 || val == 0x20 /* LM78 */
902 || val == 0x40 /* LM78-J */
903 || (val & 0xfe) == 0xc0) /* LM79 */
904 found = 1;
905
906 if (found)
907 pr_info("Found an %s chip at %#x\n",
908 val & 0x80 ? "LM79" : "LM78", (int)address);
909
910 release:
911 for (port--; port >= address; port--)
912 release_region(port, 1);
913 return found;
914 }
915
lm78_isa_device_add(unsigned short address)916 static int __init lm78_isa_device_add(unsigned short address)
917 {
918 struct resource res = {
919 .start = address,
920 .end = address + LM78_EXTENT - 1,
921 .name = "lm78",
922 .flags = IORESOURCE_IO,
923 };
924 int err;
925
926 pdev = platform_device_alloc("lm78", address);
927 if (!pdev) {
928 err = -ENOMEM;
929 pr_err("Device allocation failed\n");
930 goto exit;
931 }
932
933 err = platform_device_add_resources(pdev, &res, 1);
934 if (err) {
935 pr_err("Device resource addition failed (%d)\n", err);
936 goto exit_device_put;
937 }
938
939 err = platform_device_add(pdev);
940 if (err) {
941 pr_err("Device addition failed (%d)\n", err);
942 goto exit_device_put;
943 }
944
945 return 0;
946
947 exit_device_put:
948 platform_device_put(pdev);
949 exit:
950 pdev = NULL;
951 return err;
952 }
953
lm78_isa_register(void)954 static int __init lm78_isa_register(void)
955 {
956 int res;
957
958 if (lm78_isa_found(isa_address)) {
959 res = platform_driver_register(&lm78_isa_driver);
960 if (res)
961 goto exit;
962
963 /* Sets global pdev as a side effect */
964 res = lm78_isa_device_add(isa_address);
965 if (res)
966 goto exit_unreg_isa_driver;
967 }
968
969 return 0;
970
971 exit_unreg_isa_driver:
972 platform_driver_unregister(&lm78_isa_driver);
973 exit:
974 return res;
975 }
976
lm78_isa_unregister(void)977 static void lm78_isa_unregister(void)
978 {
979 if (pdev) {
980 platform_device_unregister(pdev);
981 platform_driver_unregister(&lm78_isa_driver);
982 }
983 }
984 #else /* !CONFIG_ISA */
985
lm78_isa_register(void)986 static int __init lm78_isa_register(void)
987 {
988 return 0;
989 }
990
lm78_isa_unregister(void)991 static void lm78_isa_unregister(void)
992 {
993 }
994 #endif /* CONFIG_ISA */
995
sm_lm78_init(void)996 static int __init sm_lm78_init(void)
997 {
998 int res;
999
1000 /*
1001 * We register the ISA device first, so that we can skip the
1002 * registration of an I2C interface to the same device.
1003 */
1004 res = lm78_isa_register();
1005 if (res)
1006 goto exit;
1007
1008 res = i2c_add_driver(&lm78_driver);
1009 if (res)
1010 goto exit_unreg_isa_device;
1011
1012 return 0;
1013
1014 exit_unreg_isa_device:
1015 lm78_isa_unregister();
1016 exit:
1017 return res;
1018 }
1019
sm_lm78_exit(void)1020 static void __exit sm_lm78_exit(void)
1021 {
1022 lm78_isa_unregister();
1023 i2c_del_driver(&lm78_driver);
1024 }
1025
1026 MODULE_AUTHOR("Frodo Looijaard, Jean Delvare <jdelvare@suse.de>");
1027 MODULE_DESCRIPTION("LM78/LM79 driver");
1028 MODULE_LICENSE("GPL");
1029
1030 module_init(sm_lm78_init);
1031 module_exit(sm_lm78_exit);
1032