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hwmon: (max6650) Add support for alarms
[GitHub/exynos8895/android_kernel_samsung_universal8895.git] / drivers / hwmon / max6650.c
CommitLineData
d20620de
HJK		 1/*
2 * max6650.c - Part of lm_sensors, Linux kernel modules for hardware
3 * monitoring.
4 *
5 * (C) 2007 by Hans J. Koch <hjk@linutronix.de>
6 *
7 * based on code written by John Morris <john.morris@spirentcom.com>
8 * Copyright (c) 2003 Spirent Communications
9 * and Claus Gindhart <claus.gindhart@kontron.com>
10 *
11 * This module has only been tested with the MAX6650 chip. It should
12 * also work with the MAX6651. It does not distinguish max6650 and max6651
13 * chips.
14 *
52b5226f 15 * The datasheet was last seen at:
d20620de
HJK		 16 *
17 * http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
18 *
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation; either version 2 of the License, or
22 * (at your option) any later version.
23 *
24 * This program is distributed in the hope that it will be useful,
25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 * GNU General Public License for more details.
28 *
29 * You should have received a copy of the GNU General Public License
30 * along with this program; if not, write to the Free Software
31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
32 */
33
34#include <linux/module.h>
35#include <linux/init.h>
36#include <linux/slab.h>
37#include <linux/jiffies.h>
38#include <linux/i2c.h>
39#include <linux/hwmon.h>
40#include <linux/hwmon-sysfs.h>
41#include <linux/err.h>
42
43/*
44 * Addresses to scan. There are four disjoint possibilities, by pin config.
45 */
46
25e9c86d
MH		 47static const unsigned short normal_i2c[] = {0x1b, 0x1f, 0x48, 0x4b,
48 I2C_CLIENT_END};
d20620de
HJK		 49
50/*
51 * Insmod parameters
52 */
53
54/* fan_voltage: 5=5V fan, 12=12V fan, 0=don't change */
55static int fan_voltage;
56/* prescaler: Possible values are 1, 2, 4, 8, 16 or 0 for don't change */
57static int prescaler;
58/* clock: The clock frequency of the chip the driver should assume */
59static int clock = 254000;
60
61module_param(fan_voltage, int, S_IRUGO);
62module_param(prescaler, int, S_IRUGO);
63module_param(clock, int, S_IRUGO);
64
65I2C_CLIENT_INSMOD_1(max6650);
66
67/*
68 * MAX 6650/6651 registers
69 */
70
71#define MAX6650_REG_SPEED 0x00
72#define MAX6650_REG_CONFIG 0x02
73#define MAX6650_REG_GPIO_DEF 0x04
74#define MAX6650_REG_DAC 0x06
75#define MAX6650_REG_ALARM_EN 0x08
76#define MAX6650_REG_ALARM 0x0A
77#define MAX6650_REG_TACH0 0x0C
78#define MAX6650_REG_TACH1 0x0E
79#define MAX6650_REG_TACH2 0x10
80#define MAX6650_REG_TACH3 0x12
81#define MAX6650_REG_GPIO_STAT 0x14
82#define MAX6650_REG_COUNT 0x16
83
84/*
85 * Config register bits
86 */
87
88#define MAX6650_CFG_V12 0x08
89#define MAX6650_CFG_PRESCALER_MASK 0x07
90#define MAX6650_CFG_PRESCALER_2 0x01
91#define MAX6650_CFG_PRESCALER_4 0x02
92#define MAX6650_CFG_PRESCALER_8 0x03
93#define MAX6650_CFG_PRESCALER_16 0x04
94#define MAX6650_CFG_MODE_MASK 0x30
95#define MAX6650_CFG_MODE_ON 0x00
96#define MAX6650_CFG_MODE_OFF 0x10
97#define MAX6650_CFG_MODE_CLOSED_LOOP 0x20
98#define MAX6650_CFG_MODE_OPEN_LOOP 0x30
99#define MAX6650_COUNT_MASK 0x03
100
52b5226f
CE		 101/*
102 * Alarm status register bits
103 */
104
105#define MAX6650_ALRM_MAX 0x01
106#define MAX6650_ALRM_MIN 0x02
107#define MAX6650_ALRM_TACH 0x04
108#define MAX6650_ALRM_GPIO1 0x08
109#define MAX6650_ALRM_GPIO2 0x10
110
d20620de
HJK		 111/* Minimum and maximum values of the FAN-RPM */
112#define FAN_RPM_MIN 240
113#define FAN_RPM_MAX 30000
114
115#define DIV_FROM_REG(reg) (1 << (reg & 7))
116
0d57abd5
JD		 117static int max6650_probe(struct i2c_client *client,
118 const struct i2c_device_id *id);
119static int max6650_detect(struct i2c_client *client, int kind,
120 struct i2c_board_info *info);
d20620de 121static int max6650_init_client(struct i2c_client *client);
0d57abd5 122static int max6650_remove(struct i2c_client *client);
d20620de
HJK		 123static struct max6650_data *max6650_update_device(struct device *dev);
124
125/*
126 * Driver data (common to all clients)
127 */
128
0d57abd5
JD		 129static const struct i2c_device_id max6650_id[] = {
130 { "max6650", max6650 },
131 { }
132};
133MODULE_DEVICE_TABLE(i2c, max6650_id);
134
d20620de 135static struct i2c_driver max6650_driver = {
0d57abd5 136 .class = I2C_CLASS_HWMON,
d20620de
HJK		 137 .driver = {
138 .name = "max6650",
139 },
0d57abd5
JD		 140 .probe = max6650_probe,
141 .remove = max6650_remove,
142 .id_table = max6650_id,
143 .detect = max6650_detect,
144 .address_data = &addr_data,
d20620de
HJK		 145};
146
147/*
148 * Client data (each client gets its own)
149 */
150
151struct max6650_data
152{
1beeffe4 153 struct device *hwmon_dev;
d20620de
HJK		 154 struct mutex update_lock;
155 char valid; /* zero until following fields are valid */
156 unsigned long last_updated; /* in jiffies */
157
158 /* register values */
159 u8 speed;
160 u8 config;
161 u8 tach[4];
162 u8 count;
163 u8 dac;
52b5226f 164 u8 alarm;
d20620de
HJK		 165};
166
167static ssize_t get_fan(struct device *dev, struct device_attribute *devattr,
168 char *buf)
169{
170 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
171 struct max6650_data *data = max6650_update_device(dev);
172 int rpm;
173
174 /*
175 * Calculation details:
176 *
177 * Each tachometer counts over an interval given by the "count"
178 * register (0.25, 0.5, 1 or 2 seconds). This module assumes
179 * that the fans produce two pulses per revolution (this seems
180 * to be the most common).
181 */
182
183 rpm = ((data->tach[attr->index] * 120) / DIV_FROM_REG(data->count));
184 return sprintf(buf, "%d\n", rpm);
185}
186
187/*
188 * Set the fan speed to the specified RPM (or read back the RPM setting).
189 * This works in closed loop mode only. Use pwm1 for open loop speed setting.
190 *
191 * The MAX6650/1 will automatically control fan speed when in closed loop
192 * mode.
193 *
194 * Assumptions:
195 *
196 * 1) The MAX6650/1 internal 254kHz clock frequency is set correctly. Use
197 * the clock module parameter if you need to fine tune this.
198 *
199 * 2) The prescaler (low three bits of the config register) has already
200 * been set to an appropriate value. Use the prescaler module parameter
201 * if your BIOS doesn't initialize the chip properly.
202 *
203 * The relevant equations are given on pages 21 and 22 of the datasheet.
204 *
205 * From the datasheet, the relevant equation when in regulation is:
206 *
207 * [fCLK / (128 x (KTACH + 1))] = 2 x FanSpeed / KSCALE
208 *
209 * where:
210 *
211 * fCLK is the oscillator frequency (either the 254kHz internal
212 * oscillator or the externally applied clock)
213 *
214 * KTACH is the value in the speed register
215 *
216 * FanSpeed is the speed of the fan in rps
217 *
218 * KSCALE is the prescaler value (1, 2, 4, 8, or 16)
219 *
220 * When reading, we need to solve for FanSpeed. When writing, we need to
221 * solve for KTACH.
222 *
223 * Note: this tachometer is completely separate from the tachometers
224 * used to measure the fan speeds. Only one fan's speed (fan1) is
225 * controlled.
226 */
227
228static ssize_t get_target(struct device *dev, struct device_attribute *devattr,
229 char *buf)
230{
231 struct max6650_data *data = max6650_update_device(dev);
232 int kscale, ktach, rpm;
233
234 /*
235 * Use the datasheet equation:
236 *
237 * FanSpeed = KSCALE x fCLK / [256 x (KTACH + 1)]
238 *
239 * then multiply by 60 to give rpm.
240 */
241
242 kscale = DIV_FROM_REG(data->config);
243 ktach = data->speed;
244 rpm = 60 * kscale * clock / (256 * (ktach + 1));
245 return sprintf(buf, "%d\n", rpm);
246}
247
248static ssize_t set_target(struct device *dev, struct device_attribute *devattr,
249 const char *buf, size_t count)
250{
251 struct i2c_client *client = to_i2c_client(dev);
252 struct max6650_data *data = i2c_get_clientdata(client);
253 int rpm = simple_strtoul(buf, NULL, 10);
254 int kscale, ktach;
255
256 rpm = SENSORS_LIMIT(rpm, FAN_RPM_MIN, FAN_RPM_MAX);
257
258 /*
259 * Divide the required speed by 60 to get from rpm to rps, then
260 * use the datasheet equation:
261 *
262 * KTACH = [(fCLK x KSCALE) / (256 x FanSpeed)] - 1
263 */
264
265 mutex_lock(&data->update_lock);
266
267 kscale = DIV_FROM_REG(data->config);
268 ktach = ((clock * kscale) / (256 * rpm / 60)) - 1;
269 if (ktach < 0)
270 ktach = 0;
271 if (ktach > 255)
272 ktach = 255;
273 data->speed = ktach;
274
275 i2c_smbus_write_byte_data(client, MAX6650_REG_SPEED, data->speed);
276
277 mutex_unlock(&data->update_lock);
278
279 return count;
280}
281
282/*
283 * Get/set the fan speed in open loop mode using pwm1 sysfs file.
284 * Speed is given as a relative value from 0 to 255, where 255 is maximum
285 * speed. Note that this is done by writing directly to the chip's DAC,
286 * it won't change the closed loop speed set by fan1_target.
287 * Also note that due to rounding errors it is possible that you don't read
288 * back exactly the value you have set.
289 */
290
291static ssize_t get_pwm(struct device *dev, struct device_attribute *devattr,
292 char *buf)
293{
294 int pwm;
295 struct max6650_data *data = max6650_update_device(dev);
296
297 /* Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans.
298 Lower DAC values mean higher speeds. */
299 if (data->config & MAX6650_CFG_V12)
300 pwm = 255 - (255 * (int)data->dac)/180;
301 else
302 pwm = 255 - (255 * (int)data->dac)/76;
303
304 if (pwm < 0)
305 pwm = 0;
306
307 return sprintf(buf, "%d\n", pwm);
308}
309
310static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
311 const char *buf, size_t count)
312{
313 struct i2c_client *client = to_i2c_client(dev);
314 struct max6650_data *data = i2c_get_clientdata(client);
315 int pwm = simple_strtoul(buf, NULL, 10);
316
317 pwm = SENSORS_LIMIT(pwm, 0, 255);
318
319 mutex_lock(&data->update_lock);
320
321 if (data->config & MAX6650_CFG_V12)
322 data->dac = 180 - (180 * pwm)/255;
323 else
324 data->dac = 76 - (76 * pwm)/255;
325
326 i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
327
328 mutex_unlock(&data->update_lock);
329
330 return count;
331}
332
333/*
334 * Get/Set controller mode:
335 * Possible values:
336 * 0 = Fan always on
337 * 1 = Open loop, Voltage is set according to speed, not regulated.
338 * 2 = Closed loop, RPM for all fans regulated by fan1 tachometer
339 */
340
341static ssize_t get_enable(struct device *dev, struct device_attribute *devattr,
342 char *buf)
343{
344 struct max6650_data *data = max6650_update_device(dev);
345 int mode = (data->config & MAX6650_CFG_MODE_MASK) >> 4;
346 int sysfs_modes[4] = {0, 1, 2, 1};
347
348 return sprintf(buf, "%d\n", sysfs_modes[mode]);
349}
350
351static ssize_t set_enable(struct device *dev, struct device_attribute *devattr,
352 const char *buf, size_t count)
353{
354 struct i2c_client *client = to_i2c_client(dev);
355 struct max6650_data *data = i2c_get_clientdata(client);
356 int mode = simple_strtoul(buf, NULL, 10);
357 int max6650_modes[3] = {0, 3, 2};
358
359 if ((mode < 0)||(mode > 2)) {
360 dev_err(&client->dev,
361 "illegal value for pwm1_enable (%d)\n", mode);
362 return -EINVAL;
363 }
364
365 mutex_lock(&data->update_lock);
366
367 data->config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
368 data->config = (data->config & ~MAX6650_CFG_MODE_MASK)
369 | (max6650_modes[mode] << 4);
370
371 i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, data->config);
372
373 mutex_unlock(&data->update_lock);
374
375 return count;
376}
377
378/*
379 * Read/write functions for fan1_div sysfs file. The MAX6650 has no such
380 * divider. We handle this by converting between divider and counttime:
381 *
382 * (counttime == k) <==> (divider == 2^k), k = 0, 1, 2, or 3
383 *
384 * Lower values of k allow to connect a faster fan without the risk of
385 * counter overflow. The price is lower resolution. You can also set counttime
386 * using the module parameter. Note that the module parameter "prescaler" also
387 * influences the behaviour. Unfortunately, there's no sysfs attribute
388 * defined for that. See the data sheet for details.
389 */
390
391static ssize_t get_div(struct device *dev, struct device_attribute *devattr,
392 char *buf)
393{
394 struct max6650_data *data = max6650_update_device(dev);
395
396 return sprintf(buf, "%d\n", DIV_FROM_REG(data->count));
397}
398
399static ssize_t set_div(struct device *dev, struct device_attribute *devattr,
400 const char *buf, size_t count)
401{
402 struct i2c_client *client = to_i2c_client(dev);
403 struct max6650_data *data = i2c_get_clientdata(client);
404 int div = simple_strtoul(buf, NULL, 10);
405
406 mutex_lock(&data->update_lock);
407 switch (div) {
408 case 1:
409 data->count = 0;
410 break;
411 case 2:
412 data->count = 1;
413 break;
414 case 4:
415 data->count = 2;
416 break;
417 case 8:
418 data->count = 3;
419 break;
420 default:
421 dev_err(&client->dev,
422 "illegal value for fan divider (%d)\n", div);
423 return -EINVAL;
424 }
425
426 i2c_smbus_write_byte_data(client, MAX6650_REG_COUNT, data->count);
427 mutex_unlock(&data->update_lock);
428
429 return count;
430}
431
52b5226f
CE		 432/*
433 * Get alarm stati:
434 * Possible values:
435 * 0 = no alarm
436 * 1 = alarm
437 */
438
439static ssize_t get_alarm(struct device *dev, struct device_attribute *devattr,
440 char *buf)
441{
442 struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
443 struct max6650_data *data = max6650_update_device(dev);
444 struct i2c_client *client = to_i2c_client(dev);
445 int alarm = 0;
446
447 if (data->alarm & attr->index) {
448 mutex_lock(&data->update_lock);
449 alarm = 1;
450 data->alarm &= ~attr->index;
451 data->alarm |= i2c_smbus_read_byte_data(client,
452 MAX6650_REG_ALARM);
453 mutex_unlock(&data->update_lock);
454 }
455
456 return sprintf(buf, "%d\n", alarm);
457}
458
d20620de
HJK		 459static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, get_fan, NULL, 0);
460static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, get_fan, NULL, 1);
461static SENSOR_DEVICE_ATTR(fan3_input, S_IRUGO, get_fan, NULL, 2);
462static SENSOR_DEVICE_ATTR(fan4_input, S_IRUGO, get_fan, NULL, 3);
463static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO, get_target, set_target);
464static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_div, set_div);
465static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, get_enable, set_enable);
466static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm);
52b5226f
CE		 467static SENSOR_DEVICE_ATTR(fan1_max_alarm, S_IRUGO, get_alarm, NULL,
468 MAX6650_ALRM_MAX);
469static SENSOR_DEVICE_ATTR(fan1_min_alarm, S_IRUGO, get_alarm, NULL,
470 MAX6650_ALRM_MIN);
471static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, get_alarm, NULL,
472 MAX6650_ALRM_TACH);
473static SENSOR_DEVICE_ATTR(gpio1_alarm, S_IRUGO, get_alarm, NULL,
474 MAX6650_ALRM_GPIO1);
475static SENSOR_DEVICE_ATTR(gpio2_alarm, S_IRUGO, get_alarm, NULL,
476 MAX6650_ALRM_GPIO2);
477
478static mode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a,
479 int n)
480{
481 struct device *dev = container_of(kobj, struct device, kobj);
482 struct i2c_client *client = to_i2c_client(dev);
483 u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN);
484 struct device_attribute *devattr;
d20620de 485
52b5226f
CE		 486 /*
487 * Hide the alarms that have not been enabled by the firmware
488 */
489
490 devattr = container_of(a, struct device_attribute, attr);
491 if (devattr == &sensor_dev_attr_fan1_max_alarm.dev_attr
492 || devattr == &sensor_dev_attr_fan1_min_alarm.dev_attr
493 || devattr == &sensor_dev_attr_fan1_fault.dev_attr
494 || devattr == &sensor_dev_attr_gpio1_alarm.dev_attr
495 || devattr == &sensor_dev_attr_gpio2_alarm.dev_attr) {
496 if (!(alarm_en & to_sensor_dev_attr(devattr)->index))
497 return 0;
498 }
499
500 return a->mode;
501}
d20620de
HJK		 502
503static struct attribute *max6650_attrs[] = {
504 &sensor_dev_attr_fan1_input.dev_attr.attr,
505 &sensor_dev_attr_fan2_input.dev_attr.attr,
506 &sensor_dev_attr_fan3_input.dev_attr.attr,
507 &sensor_dev_attr_fan4_input.dev_attr.attr,
508 &dev_attr_fan1_target.attr,
509 &dev_attr_fan1_div.attr,
510 &dev_attr_pwm1_enable.attr,
511 &dev_attr_pwm1.attr,
52b5226f
CE		 512 &sensor_dev_attr_fan1_max_alarm.dev_attr.attr,
513 &sensor_dev_attr_fan1_min_alarm.dev_attr.attr,
514 &sensor_dev_attr_fan1_fault.dev_attr.attr,
515 &sensor_dev_attr_gpio1_alarm.dev_attr.attr,
516 &sensor_dev_attr_gpio2_alarm.dev_attr.attr,
d20620de
HJK		 517 NULL
518};
519
520static struct attribute_group max6650_attr_grp = {
521 .attrs = max6650_attrs,
52b5226f 522 .is_visible = max6650_attrs_visible,
d20620de
HJK		 523};
524
525/*
526 * Real code
527 */
528
0d57abd5
JD		 529/* Return 0 if detection is successful, -ENODEV otherwise */
530static int max6650_detect(struct i2c_client *client, int kind,
531 struct i2c_board_info *info)
d20620de 532{
0d57abd5
JD		 533 struct i2c_adapter *adapter = client->adapter;
534 int address = client->addr;
d20620de
HJK		 535
536 dev_dbg(&adapter->dev, "max6650_detect called, kind = %d\n", kind);
537
538 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
539 dev_dbg(&adapter->dev, "max6650: I2C bus doesn't support "
540 "byte read mode, skipping.\n");
0d57abd5 541 return -ENODEV;
d20620de
HJK		 542 }
543
d20620de
HJK		 544 /*
545 * Now we do the remaining detection. A negative kind means that
546 * the driver was loaded with no force parameter (default), so we
547 * must both detect and identify the chip (actually there is only
548 * one possible kind of chip for now, max6650). A zero kind means that
549 * the driver was loaded with the force parameter, the detection
550 * step shall be skipped. A positive kind means that the driver
551 * was loaded with the force parameter and a given kind of chip is
552 * requested, so both the detection and the identification steps
553 * are skipped.
554 *
555 * Currently I can find no way to distinguish between a MAX6650 and
556 * a MAX6651. This driver has only been tried on the former.
557 */
558
559 if ((kind < 0) &&
560 ( (i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG) & 0xC0)
561 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_GPIO_STAT) & 0xE0)
562 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN) & 0xE0)
563 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM) & 0xE0)
564 ||(i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT) & 0xFC))) {
565 dev_dbg(&adapter->dev,
566 "max6650: detection failed at 0x%02x.\n", address);
0d57abd5 567 return -ENODEV;
d20620de
HJK		 568 }
569
570 dev_info(&adapter->dev, "max6650: chip found at 0x%02x.\n", address);
571
0d57abd5 572 strlcpy(info->type, "max6650", I2C_NAME_SIZE);
d20620de 573
0d57abd5
JD		 574 return 0;
575}
576
577static int max6650_probe(struct i2c_client *client,
578 const struct i2c_device_id *id)
579{
580 struct max6650_data *data;
581 int err;
582
583 if (!(data = kzalloc(sizeof(struct max6650_data), GFP_KERNEL))) {
584 dev_err(&client->dev, "out of memory.\n");
585 return -ENOMEM;
d20620de
HJK		 586 }
587
0d57abd5
JD		 588 i2c_set_clientdata(client, data);
589 mutex_init(&data->update_lock);
590
d20620de
HJK		 591 /*
592 * Initialize the max6650 chip
593 */
0d57abd5
JD		 594 err = max6650_init_client(client);
595 if (err)
596 goto err_free;
d20620de
HJK		 597
598 err = sysfs_create_group(&client->dev.kobj, &max6650_attr_grp);
599 if (err)
0d57abd5 600 goto err_free;
d20620de 601
1beeffe4
TJ		 602 data->hwmon_dev = hwmon_device_register(&client->dev);
603 if (!IS_ERR(data->hwmon_dev))
d20620de
HJK		 604 return 0;
605
1beeffe4 606 err = PTR_ERR(data->hwmon_dev);
d20620de
HJK		 607 dev_err(&client->dev, "error registering hwmon device.\n");
608 sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp);
d20620de
HJK		 609err_free:
610 kfree(data);
611 return err;
612}
613
0d57abd5 614static int max6650_remove(struct i2c_client *client)
d20620de
HJK		 615{
616 struct max6650_data *data = i2c_get_clientdata(client);
d20620de
HJK		 617
618 sysfs_remove_group(&client->dev.kobj, &max6650_attr_grp);
1beeffe4 619 hwmon_device_unregister(data->hwmon_dev);
0d57abd5
JD		 620 kfree(data);
621 return 0;
d20620de
HJK		 622}
623
624static int max6650_init_client(struct i2c_client *client)
625{
626 struct max6650_data *data = i2c_get_clientdata(client);
627 int config;
628 int err = -EIO;
629
630 config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG);
631
632 if (config < 0) {
633 dev_err(&client->dev, "Error reading config, aborting.\n");
634 return err;
635 }
636
637 switch (fan_voltage) {
638 case 0:
639 break;
640 case 5:
641 config &= ~MAX6650_CFG_V12;
642 break;
643 case 12:
644 config |= MAX6650_CFG_V12;
645 break;
646 default:
647 dev_err(&client->dev,
648 "illegal value for fan_voltage (%d)\n",
649 fan_voltage);
650 }
651
652 dev_info(&client->dev, "Fan voltage is set to %dV.\n",
653 (config & MAX6650_CFG_V12) ? 12 : 5);
654
655 switch (prescaler) {
656 case 0:
657 break;
658 case 1:
659 config &= ~MAX6650_CFG_PRESCALER_MASK;
660 break;
661 case 2:
662 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
663 | MAX6650_CFG_PRESCALER_2;
664 break;
665 case 4:
666 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
667 | MAX6650_CFG_PRESCALER_4;
668 break;
669 case 8:
670 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
671 | MAX6650_CFG_PRESCALER_8;
672 break;
673 case 16:
674 config = (config & ~MAX6650_CFG_PRESCALER_MASK)
675 | MAX6650_CFG_PRESCALER_16;
676 break;
677 default:
678 dev_err(&client->dev,
679 "illegal value for prescaler (%d)\n",
680 prescaler);
681 }
682
683 dev_info(&client->dev, "Prescaler is set to %d.\n",
684 1 << (config & MAX6650_CFG_PRESCALER_MASK));
685
686 /* If mode is set to "full off", we change it to "open loop" and
687 * set DAC to 255, which has the same effect. We do this because
688 * there's no "full off" mode defined in hwmon specifcations.
689 */
690
691 if ((config & MAX6650_CFG_MODE_MASK) == MAX6650_CFG_MODE_OFF) {
692 dev_dbg(&client->dev, "Change mode to open loop, full off.\n");
693 config = (config & ~MAX6650_CFG_MODE_MASK)
694 | MAX6650_CFG_MODE_OPEN_LOOP;
695 if (i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, 255)) {
696 dev_err(&client->dev, "DAC write error, aborting.\n");
697 return err;
698 }
699 }
700
701 if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) {
702 dev_err(&client->dev, "Config write error, aborting.\n");
703 return err;
704 }
705
706 data->config = config;
707 data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT);
708
709 return 0;
710}
711
712static const u8 tach_reg[] = {
713 MAX6650_REG_TACH0,
714 MAX6650_REG_TACH1,
715 MAX6650_REG_TACH2,
716 MAX6650_REG_TACH3,
717};
718
719static struct max6650_data *max6650_update_device(struct device *dev)
720{
721 int i;
722 struct i2c_client *client = to_i2c_client(dev);
723 struct max6650_data *data = i2c_get_clientdata(client);
724
725 mutex_lock(&data->update_lock);
726
727 if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
728 data->speed = i2c_smbus_read_byte_data(client,
729 MAX6650_REG_SPEED);
730 data->config = i2c_smbus_read_byte_data(client,
731 MAX6650_REG_CONFIG);
732 for (i = 0; i < 4; i++) {
733 data->tach[i] = i2c_smbus_read_byte_data(client,
734 tach_reg[i]);
735 }
736 data->count = i2c_smbus_read_byte_data(client,
737 MAX6650_REG_COUNT);
738 data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC);
739
52b5226f
CE		 740 /* Alarms are cleared on read in case the condition that
741 * caused the alarm is removed. Keep the value latched here
742 * for providing the register through different alarm files. */
743 data->alarm |= i2c_smbus_read_byte_data(client,
744 MAX6650_REG_ALARM);
745
d20620de
HJK		 746 data->last_updated = jiffies;
747 data->valid = 1;
748 }
749
750 mutex_unlock(&data->update_lock);
751
752 return data;
753}
754
755static int __init sensors_max6650_init(void)
756{
757 return i2c_add_driver(&max6650_driver);
758}
759
760static void __exit sensors_max6650_exit(void)
761{
762 i2c_del_driver(&max6650_driver);
763}
764
765MODULE_AUTHOR("Hans J. Koch");
766MODULE_DESCRIPTION("MAX6650 sensor driver");
767MODULE_LICENSE("GPL");
768
769module_init(sensors_max6650_init);
770module_exit(sensors_max6650_exit);