1 // SPDX-License-Identifier: GPL-2.0-only
3 * Device driver for the i2c thermostat found on the iBook G4, Albook G4
5 * Copyright (C) 2003, 2004 Colin Leroy, Rasmus Rohde, Benjamin Herrenschmidt
7 * Documentation from 115254175ADT7467_pra.pdf and 3686221171167ADT7460_b.pdf
8 * https://www.onsemi.com/PowerSolutions/product.do?id=ADT7467
9 * https://www.onsemi.com/PowerSolutions/product.do?id=ADT7460
13 #include <linux/types.h>
14 #include <linux/module.h>
15 #include <linux/errno.h>
16 #include <linux/kernel.h>
17 #include <linux/delay.h>
18 #include <linux/sched.h>
19 #include <linux/i2c.h>
20 #include <linux/slab.h>
21 #include <linux/init.h>
22 #include <linux/spinlock.h>
23 #include <linux/wait.h>
24 #include <linux/suspend.h>
25 #include <linux/kthread.h>
26 #include <linux/moduleparam.h>
27 #include <linux/freezer.h>
28 #include <linux/of_platform.h>
31 #include <asm/machdep.h>
33 #include <asm/sections.h>
37 #define CONFIG_REG 0x40
38 #define MANUAL_MASK 0xe0
39 #define AUTO_MASK 0x20
40 #define INVERT_MASK 0x10
42 static u8 TEMP_REG
[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
43 static u8 LIMIT_REG
[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
44 static u8 MANUAL_MODE
[2] = {0x5c, 0x5d};
45 static u8 REM_CONTROL
[2] = {0x00, 0x40};
46 static u8 FAN_SPEED
[2] = {0x28, 0x2a};
47 static u8 FAN_SPD_SET
[2] = {0x30, 0x31};
49 static u8 default_limits_local
[3] = {70, 50, 70}; /* local, sensor1, sensor2 */
50 static u8 default_limits_chip
[3] = {80, 65, 80}; /* local, sensor1, sensor2 */
51 static const char *sensor_location
[3] = { "?", "?", "?" };
53 static int limit_adjust
;
54 static int fan_speed
= -1;
57 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
58 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
60 MODULE_LICENSE("GPL");
62 module_param(limit_adjust
, int, 0644);
63 MODULE_PARM_DESC(limit_adjust
,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
66 module_param(fan_speed
, int, 0644);
67 MODULE_PARM_DESC(fan_speed
,"Specify starting fan speed (0-255) "
70 module_param(verbose
, bool, 0);
71 MODULE_PARM_DESC(verbose
,"Verbose log operations "
75 struct i2c_client
*clt
;
83 struct task_struct
*thread
;
84 struct platform_device
*pdev
;
91 static void write_both_fan_speed(struct thermostat
*th
, int speed
);
92 static void write_fan_speed(struct thermostat
*th
, int speed
, int fan
);
95 write_reg(struct thermostat
* th
, int reg
, u8 data
)
102 rc
= i2c_master_send(th
->clt
, (const char *)tmp
, 2);
111 read_reg(struct thermostat
* th
, int reg
)
117 rc
= i2c_master_send(th
->clt
, ®_addr
, 1);
122 rc
= i2c_master_recv(th
->clt
, (char *)&data
, 1);
128 static int read_fan_speed(struct thermostat
*th
, u8 addr
)
133 /* should start with low byte */
134 tmp
[1] = read_reg(th
, addr
);
135 tmp
[0] = read_reg(th
, addr
+ 1);
137 res
= tmp
[1] + (tmp
[0] << 8);
138 /* "a value of 0xffff means that the fan has stopped" */
139 return (res
== 0xffff ? 0 : (90000*60)/res
);
142 static void write_both_fan_speed(struct thermostat
*th
, int speed
)
144 write_fan_speed(th
, speed
, 0);
145 if (th
->type
== ADT7460
)
146 write_fan_speed(th
, speed
, 1);
149 static void write_fan_speed(struct thermostat
*th
, int speed
, int fan
)
158 if (th
->type
== ADT7467
&& fan
== 1)
161 if (th
->last_speed
[fan
] != speed
) {
164 printk(KERN_DEBUG
"adt746x: Setting speed to automatic "
165 "for %s fan.\n", sensor_location
[fan
+1]);
167 printk(KERN_DEBUG
"adt746x: Setting speed to %d "
168 "for %s fan.\n", speed
, sensor_location
[fan
+1]);
174 manual
= read_reg(th
, MANUAL_MODE
[fan
]);
175 manual
&= ~INVERT_MASK
;
176 write_reg(th
, MANUAL_MODE
[fan
],
177 manual
| MANUAL_MASK
| th
->pwm_inv
[fan
]);
178 write_reg(th
, FAN_SPD_SET
[fan
], speed
);
180 /* back to automatic */
181 if(th
->type
== ADT7460
) {
182 manual
= read_reg(th
,
183 MANUAL_MODE
[fan
]) & (~MANUAL_MASK
);
184 manual
&= ~INVERT_MASK
;
185 manual
|= th
->pwm_inv
[fan
];
187 MANUAL_MODE
[fan
], manual
|REM_CONTROL
[fan
]);
189 manual
= read_reg(th
, MANUAL_MODE
[fan
]);
190 manual
&= ~INVERT_MASK
;
191 manual
|= th
->pwm_inv
[fan
];
192 write_reg(th
, MANUAL_MODE
[fan
], manual
&(~AUTO_MASK
));
196 th
->last_speed
[fan
] = speed
;
199 static void read_sensors(struct thermostat
*th
)
203 for (i
= 0; i
< 3; i
++)
204 th
->temps
[i
] = read_reg(th
, TEMP_REG
[i
]);
208 static void display_stats(struct thermostat
*th
)
210 if (th
->temps
[0] != th
->cached_temp
[0]
211 || th
->temps
[1] != th
->cached_temp
[1]
212 || th
->temps
[2] != th
->cached_temp
[2]) {
213 printk(KERN_INFO
"adt746x: Temperature infos:"
214 " thermostats: %d,%d,%d;"
216 " fan speed: %d RPM\n",
217 th
->temps
[0], th
->temps
[1], th
->temps
[2],
218 th
->limits
[0], th
->limits
[1], th
->limits
[2],
219 read_fan_speed(th
, FAN_SPEED
[0]));
221 th
->cached_temp
[0] = th
->temps
[0];
222 th
->cached_temp
[1] = th
->temps
[1];
223 th
->cached_temp
[2] = th
->temps
[2];
227 static void update_fans_speed (struct thermostat
*th
)
229 int lastvar
= 0; /* last variation, for iBook */
232 /* we don't care about local sensor, so we start at sensor 1 */
233 for (i
= 1; i
< 3; i
++) {
234 bool started
= false;
235 int fan_number
= (th
->type
== ADT7460
&& i
== 2);
236 int var
= th
->temps
[i
] - th
->limits
[i
];
239 int step
= (255 - fan_speed
) / 7;
242 /* hysteresis : change fan speed only if variation is
243 * more than two degrees */
244 if (abs(var
- th
->last_var
[fan_number
]) < 2)
248 new_speed
= fan_speed
+ ((var
-1)*step
);
250 if (new_speed
< fan_speed
)
251 new_speed
= fan_speed
;
256 printk(KERN_DEBUG
"adt746x: Setting fans speed to %d "
257 "(limit exceeded by %d on %s)\n",
259 sensor_location
[fan_number
+1]);
260 write_both_fan_speed(th
, new_speed
);
261 th
->last_var
[fan_number
] = var
;
262 } else if (var
< -2) {
263 /* don't stop fan if sensor2 is cold and sensor1 is not
264 * so cold (lastvar >= -1) */
265 if (i
== 2 && lastvar
< -1) {
266 if (th
->last_speed
[fan_number
] != 0)
268 printk(KERN_DEBUG
"adt746x: Stopping "
270 write_both_fan_speed(th
, 0);
277 return; /* we don't want to re-stop the fan
278 * if sensor1 is heating and sensor2 is not */
282 static int monitor_task(void *arg
)
284 struct thermostat
* th
= arg
;
287 while(!kthread_should_stop()) {
289 msleep_interruptible(2000);
299 update_fans_speed(th
);
310 static void set_limit(struct thermostat
*th
, int i
)
312 /* Set sensor1 limit higher to avoid powerdowns */
313 th
->limits
[i
] = default_limits_chip
[i
] + limit_adjust
;
314 write_reg(th
, LIMIT_REG
[i
], th
->limits
[i
]);
316 /* set our limits to normal */
317 th
->limits
[i
] = default_limits_local
[i
] + limit_adjust
;
320 #define BUILD_SHOW_FUNC_INT(name, data) \
321 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
323 struct thermostat *th = dev_get_drvdata(dev); \
324 return sprintf(buf, "%d\n", data); \
327 #define BUILD_SHOW_FUNC_INT_LITE(name, data) \
328 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
330 return sprintf(buf, "%d\n", data); \
333 #define BUILD_SHOW_FUNC_STR(name, data) \
334 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
336 return sprintf(buf, "%s\n", data); \
339 #define BUILD_SHOW_FUNC_FAN(name, data) \
340 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
342 struct thermostat *th = dev_get_drvdata(dev); \
343 return sprintf(buf, "%d (%d rpm)\n", \
344 th->last_speed[data], \
345 read_fan_speed(th, FAN_SPEED[data]) \
349 #define BUILD_STORE_FUNC_DEG(name, data) \
350 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
352 struct thermostat *th = dev_get_drvdata(dev); \
355 val = simple_strtol(buf, NULL, 10); \
356 printk(KERN_INFO "Adjusting limits by %d degrees\n", val); \
357 limit_adjust = val; \
358 for (i=0; i < 3; i++) \
363 #define BUILD_STORE_FUNC_INT(name, data) \
364 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
367 val = simple_strtol(buf, NULL, 10); \
368 if (val < 0 || val > 255) \
370 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
375 BUILD_SHOW_FUNC_INT(sensor1_temperature
, (read_reg(th
, TEMP_REG
[1])))
376 BUILD_SHOW_FUNC_INT(sensor2_temperature
, (read_reg(th
, TEMP_REG
[2])))
377 BUILD_SHOW_FUNC_INT(sensor1_limit
, th
->limits
[1])
378 BUILD_SHOW_FUNC_INT(sensor2_limit
, th
->limits
[2])
379 BUILD_SHOW_FUNC_STR(sensor1_location
, sensor_location
[1])
380 BUILD_SHOW_FUNC_STR(sensor2_location
, sensor_location
[2])
382 BUILD_SHOW_FUNC_INT_LITE(specified_fan_speed
, fan_speed
)
383 BUILD_STORE_FUNC_INT(specified_fan_speed
,fan_speed
)
385 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed
, 0)
386 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed
, 1)
388 BUILD_SHOW_FUNC_INT_LITE(limit_adjust
, limit_adjust
)
389 BUILD_STORE_FUNC_DEG(limit_adjust
, th
)
391 static DEVICE_ATTR(sensor1_temperature
, S_IRUGO
,
392 show_sensor1_temperature
,NULL
);
393 static DEVICE_ATTR(sensor2_temperature
, S_IRUGO
,
394 show_sensor2_temperature
,NULL
);
395 static DEVICE_ATTR(sensor1_limit
, S_IRUGO
,
396 show_sensor1_limit
, NULL
);
397 static DEVICE_ATTR(sensor2_limit
, S_IRUGO
,
398 show_sensor2_limit
, NULL
);
399 static DEVICE_ATTR(sensor1_location
, S_IRUGO
,
400 show_sensor1_location
, NULL
);
401 static DEVICE_ATTR(sensor2_location
, S_IRUGO
,
402 show_sensor2_location
, NULL
);
404 static DEVICE_ATTR(specified_fan_speed
, S_IRUSR
|S_IWUSR
|S_IRGRP
|S_IROTH
,
405 show_specified_fan_speed
,store_specified_fan_speed
);
407 static DEVICE_ATTR(sensor1_fan_speed
, S_IRUGO
,
408 show_sensor1_fan_speed
, NULL
);
409 static DEVICE_ATTR(sensor2_fan_speed
, S_IRUGO
,
410 show_sensor2_fan_speed
, NULL
);
412 static DEVICE_ATTR(limit_adjust
, S_IRUSR
|S_IWUSR
|S_IRGRP
|S_IROTH
,
413 show_limit_adjust
, store_limit_adjust
);
415 static void thermostat_create_files(struct thermostat
*th
)
417 struct device_node
*np
= th
->clt
->dev
.of_node
;
421 /* To maintain ABI compatibility with userspace, create
422 * the old style platform driver and attach the attributes
425 th
->pdev
= of_platform_device_create(np
, "temperatures", NULL
);
428 dev
= &th
->pdev
->dev
;
429 dev_set_drvdata(dev
, th
);
430 err
= device_create_file(dev
, &dev_attr_sensor1_temperature
);
431 err
|= device_create_file(dev
, &dev_attr_sensor2_temperature
);
432 err
|= device_create_file(dev
, &dev_attr_sensor1_limit
);
433 err
|= device_create_file(dev
, &dev_attr_sensor2_limit
);
434 err
|= device_create_file(dev
, &dev_attr_sensor1_location
);
435 err
|= device_create_file(dev
, &dev_attr_sensor2_location
);
436 err
|= device_create_file(dev
, &dev_attr_limit_adjust
);
437 err
|= device_create_file(dev
, &dev_attr_specified_fan_speed
);
438 err
|= device_create_file(dev
, &dev_attr_sensor1_fan_speed
);
439 if(th
->type
== ADT7460
)
440 err
|= device_create_file(dev
, &dev_attr_sensor2_fan_speed
);
443 "Failed to create temperature attribute file(s).\n");
446 static void thermostat_remove_files(struct thermostat
*th
)
452 dev
= &th
->pdev
->dev
;
453 device_remove_file(dev
, &dev_attr_sensor1_temperature
);
454 device_remove_file(dev
, &dev_attr_sensor2_temperature
);
455 device_remove_file(dev
, &dev_attr_sensor1_limit
);
456 device_remove_file(dev
, &dev_attr_sensor2_limit
);
457 device_remove_file(dev
, &dev_attr_sensor1_location
);
458 device_remove_file(dev
, &dev_attr_sensor2_location
);
459 device_remove_file(dev
, &dev_attr_limit_adjust
);
460 device_remove_file(dev
, &dev_attr_specified_fan_speed
);
461 device_remove_file(dev
, &dev_attr_sensor1_fan_speed
);
462 if (th
->type
== ADT7460
)
463 device_remove_file(dev
, &dev_attr_sensor2_fan_speed
);
464 of_device_unregister(th
->pdev
);
468 static int probe_thermostat(struct i2c_client
*client
,
469 const struct i2c_device_id
*id
)
471 struct device_node
*np
= client
->dev
.of_node
;
472 struct thermostat
* th
;
474 int i
, rc
, vers
, offset
= 0;
478 prop
= of_get_property(np
, "hwsensor-params-version", NULL
);
481 vers
= be32_to_cpup(prop
);
482 printk(KERN_INFO
"adt746x: version %d (%ssupported)\n",
483 vers
, vers
== 1 ? "" : "un");
487 if (of_get_property(np
, "hwsensor-location", NULL
)) {
488 for (i
= 0; i
< 3; i
++) {
489 sensor_location
[i
] = of_get_property(np
,
490 "hwsensor-location", NULL
) + offset
;
492 if (sensor_location
[i
] == NULL
)
493 sensor_location
[i
] = "";
495 printk(KERN_INFO
"sensor %d: %s\n", i
, sensor_location
[i
]);
496 offset
+= strlen(sensor_location
[i
]) + 1;
500 th
= kzalloc(sizeof(struct thermostat
), GFP_KERNEL
);
504 i2c_set_clientdata(client
, th
);
506 th
->type
= id
->driver_data
;
508 rc
= read_reg(th
, CONFIG_REG
);
510 dev_err(&client
->dev
, "Thermostat failed to read config!\n");
515 /* force manual control to start the fan quieter */
519 if (th
->type
== ADT7460
) {
520 printk(KERN_INFO
"adt746x: ADT7460 initializing\n");
521 /* The 7460 needs to be started explicitly */
522 write_reg(th
, CONFIG_REG
, 1);
524 printk(KERN_INFO
"adt746x: ADT7467 initializing\n");
526 for (i
= 0; i
< 3; i
++) {
527 th
->initial_limits
[i
] = read_reg(th
, LIMIT_REG
[i
]);
531 printk(KERN_INFO
"adt746x: Lowering max temperatures from %d, %d, %d"
533 th
->initial_limits
[0], th
->initial_limits
[1],
534 th
->initial_limits
[2], th
->limits
[0], th
->limits
[1],
537 /* record invert bit status because fw can corrupt it after suspend */
538 th
->pwm_inv
[0] = read_reg(th
, MANUAL_MODE
[0]) & INVERT_MASK
;
539 th
->pwm_inv
[1] = read_reg(th
, MANUAL_MODE
[1]) & INVERT_MASK
;
541 /* be sure to really write fan speed the first time */
542 th
->last_speed
[0] = -2;
543 th
->last_speed
[1] = -2;
544 th
->last_var
[0] = -80;
545 th
->last_var
[1] = -80;
547 if (fan_speed
!= -1) {
548 /* manual mode, stop fans */
549 write_both_fan_speed(th
, 0);
552 write_both_fan_speed(th
, -1);
555 th
->thread
= kthread_run(monitor_task
, th
, "kfand");
556 if (th
->thread
== ERR_PTR(-ENOMEM
)) {
557 printk(KERN_INFO
"adt746x: Kthread creation failed\n");
562 thermostat_create_files(th
);
567 static int remove_thermostat(struct i2c_client
*client
)
569 struct thermostat
*th
= i2c_get_clientdata(client
);
572 thermostat_remove_files(th
);
574 if (th
->thread
!= NULL
)
575 kthread_stop(th
->thread
);
577 printk(KERN_INFO
"adt746x: Putting max temperatures back from "
578 "%d, %d, %d to %d, %d, %d\n",
579 th
->limits
[0], th
->limits
[1], th
->limits
[2],
580 th
->initial_limits
[0], th
->initial_limits
[1],
581 th
->initial_limits
[2]);
583 for (i
= 0; i
< 3; i
++)
584 write_reg(th
, LIMIT_REG
[i
], th
->initial_limits
[i
]);
586 write_both_fan_speed(th
, -1);
593 static const struct i2c_device_id therm_adt746x_id
[] = {
594 { "MAC,adt7460", ADT7460
},
595 { "MAC,adt7467", ADT7467
},
598 MODULE_DEVICE_TABLE(i2c
, therm_adt746x_id
);
600 static struct i2c_driver thermostat_driver
= {
602 .name
= "therm_adt746x",
604 .probe
= probe_thermostat
,
605 .remove
= remove_thermostat
,
606 .id_table
= therm_adt746x_id
,
609 static int __init
thermostat_init(void)
611 #ifndef CONFIG_I2C_POWERMAC
612 request_module("i2c-powermac");
615 return i2c_add_driver(&thermostat_driver
);
618 static void __exit
thermostat_exit(void)
620 i2c_del_driver(&thermostat_driver
);
623 module_init(thermostat_init
);
624 module_exit(thermostat_exit
);