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>
29 #include <linux/of_platform.h>
30 #include <linux/platform_device.h>
32 #include <asm/machdep.h>
34 #include <asm/sections.h>
38 #define CONFIG_REG 0x40
39 #define MANUAL_MASK 0xe0
40 #define AUTO_MASK 0x20
41 #define INVERT_MASK 0x10
43 static u8 TEMP_REG
[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
44 static u8 LIMIT_REG
[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
45 static u8 MANUAL_MODE
[2] = {0x5c, 0x5d};
46 static u8 REM_CONTROL
[2] = {0x00, 0x40};
47 static u8 FAN_SPEED
[2] = {0x28, 0x2a};
48 static u8 FAN_SPD_SET
[2] = {0x30, 0x31};
50 static u8 default_limits_local
[3] = {70, 50, 70}; /* local, sensor1, sensor2 */
51 static u8 default_limits_chip
[3] = {80, 65, 80}; /* local, sensor1, sensor2 */
52 static const char *sensor_location
[3] = { "?", "?", "?" };
54 static int limit_adjust
;
55 static int fan_speed
= -1;
58 MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
59 MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
61 MODULE_LICENSE("GPL");
63 module_param(limit_adjust
, int, 0644);
64 MODULE_PARM_DESC(limit_adjust
,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
67 module_param(fan_speed
, int, 0644);
68 MODULE_PARM_DESC(fan_speed
,"Specify starting fan speed (0-255) "
71 module_param(verbose
, bool, 0);
72 MODULE_PARM_DESC(verbose
,"Verbose log operations "
76 struct i2c_client
*clt
;
84 struct task_struct
*thread
;
85 struct platform_device
*pdev
;
92 static void write_both_fan_speed(struct thermostat
*th
, int speed
);
93 static void write_fan_speed(struct thermostat
*th
, int speed
, int fan
);
96 write_reg(struct thermostat
* th
, int reg
, u8 data
)
103 rc
= i2c_master_send(th
->clt
, (const char *)tmp
, 2);
112 read_reg(struct thermostat
* th
, int reg
)
118 rc
= i2c_master_send(th
->clt
, ®_addr
, 1);
123 rc
= i2c_master_recv(th
->clt
, (char *)&data
, 1);
129 static int read_fan_speed(struct thermostat
*th
, u8 addr
)
134 /* should start with low byte */
135 tmp
[1] = read_reg(th
, addr
);
136 tmp
[0] = read_reg(th
, addr
+ 1);
138 res
= tmp
[1] + (tmp
[0] << 8);
139 /* "a value of 0xffff means that the fan has stopped" */
140 return (res
== 0xffff ? 0 : (90000*60)/res
);
143 static void write_both_fan_speed(struct thermostat
*th
, int speed
)
145 write_fan_speed(th
, speed
, 0);
146 if (th
->type
== ADT7460
)
147 write_fan_speed(th
, speed
, 1);
150 static void write_fan_speed(struct thermostat
*th
, int speed
, int fan
)
159 if (th
->type
== ADT7467
&& fan
== 1)
162 if (th
->last_speed
[fan
] != speed
) {
165 printk(KERN_DEBUG
"adt746x: Setting speed to automatic "
166 "for %s fan.\n", sensor_location
[fan
+1]);
168 printk(KERN_DEBUG
"adt746x: Setting speed to %d "
169 "for %s fan.\n", speed
, sensor_location
[fan
+1]);
175 manual
= read_reg(th
, MANUAL_MODE
[fan
]);
176 manual
&= ~INVERT_MASK
;
177 write_reg(th
, MANUAL_MODE
[fan
],
178 manual
| MANUAL_MASK
| th
->pwm_inv
[fan
]);
179 write_reg(th
, FAN_SPD_SET
[fan
], speed
);
181 /* back to automatic */
182 if(th
->type
== ADT7460
) {
183 manual
= read_reg(th
,
184 MANUAL_MODE
[fan
]) & (~MANUAL_MASK
);
185 manual
&= ~INVERT_MASK
;
186 manual
|= th
->pwm_inv
[fan
];
188 MANUAL_MODE
[fan
], manual
|REM_CONTROL
[fan
]);
190 manual
= read_reg(th
, MANUAL_MODE
[fan
]);
191 manual
&= ~INVERT_MASK
;
192 manual
|= th
->pwm_inv
[fan
];
193 write_reg(th
, MANUAL_MODE
[fan
], manual
&(~AUTO_MASK
));
197 th
->last_speed
[fan
] = speed
;
200 static void read_sensors(struct thermostat
*th
)
204 for (i
= 0; i
< 3; i
++)
205 th
->temps
[i
] = read_reg(th
, TEMP_REG
[i
]);
209 static void display_stats(struct thermostat
*th
)
211 if (th
->temps
[0] != th
->cached_temp
[0]
212 || th
->temps
[1] != th
->cached_temp
[1]
213 || th
->temps
[2] != th
->cached_temp
[2]) {
214 printk(KERN_INFO
"adt746x: Temperature infos:"
215 " thermostats: %d,%d,%d;"
217 " fan speed: %d RPM\n",
218 th
->temps
[0], th
->temps
[1], th
->temps
[2],
219 th
->limits
[0], th
->limits
[1], th
->limits
[2],
220 read_fan_speed(th
, FAN_SPEED
[0]));
222 th
->cached_temp
[0] = th
->temps
[0];
223 th
->cached_temp
[1] = th
->temps
[1];
224 th
->cached_temp
[2] = th
->temps
[2];
228 static void update_fans_speed (struct thermostat
*th
)
230 int lastvar
= 0; /* last variation, for iBook */
233 /* we don't care about local sensor, so we start at sensor 1 */
234 for (i
= 1; i
< 3; i
++) {
235 bool started
= false;
236 int fan_number
= (th
->type
== ADT7460
&& i
== 2);
237 int var
= th
->temps
[i
] - th
->limits
[i
];
240 int step
= (255 - fan_speed
) / 7;
243 /* hysteresis : change fan speed only if variation is
244 * more than two degrees */
245 if (abs(var
- th
->last_var
[fan_number
]) < 2)
249 new_speed
= fan_speed
+ ((var
-1)*step
);
251 if (new_speed
< fan_speed
)
252 new_speed
= fan_speed
;
257 printk(KERN_DEBUG
"adt746x: Setting fans speed to %d "
258 "(limit exceeded by %d on %s)\n",
260 sensor_location
[fan_number
+1]);
261 write_both_fan_speed(th
, new_speed
);
262 th
->last_var
[fan_number
] = var
;
263 } else if (var
< -2) {
264 /* don't stop fan if sensor2 is cold and sensor1 is not
265 * so cold (lastvar >= -1) */
266 if (i
== 2 && lastvar
< -1) {
267 if (th
->last_speed
[fan_number
] != 0)
269 printk(KERN_DEBUG
"adt746x: Stopping "
271 write_both_fan_speed(th
, 0);
278 return; /* we don't want to re-stop the fan
279 * if sensor1 is heating and sensor2 is not */
283 static int monitor_task(void *arg
)
285 struct thermostat
* th
= arg
;
288 while(!kthread_should_stop()) {
290 msleep_interruptible(2000);
300 update_fans_speed(th
);
311 static void set_limit(struct thermostat
*th
, int i
)
313 /* Set sensor1 limit higher to avoid powerdowns */
314 th
->limits
[i
] = default_limits_chip
[i
] + limit_adjust
;
315 write_reg(th
, LIMIT_REG
[i
], th
->limits
[i
]);
317 /* set our limits to normal */
318 th
->limits
[i
] = default_limits_local
[i
] + limit_adjust
;
321 #define BUILD_SHOW_FUNC_INT(name, data) \
322 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
324 struct thermostat *th = dev_get_drvdata(dev); \
325 return sprintf(buf, "%d\n", data); \
328 #define BUILD_SHOW_FUNC_INT_LITE(name, data) \
329 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
331 return sprintf(buf, "%d\n", data); \
334 #define BUILD_SHOW_FUNC_STR(name, data) \
335 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
337 return sprintf(buf, "%s\n", data); \
340 #define BUILD_SHOW_FUNC_FAN(name, data) \
341 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
343 struct thermostat *th = dev_get_drvdata(dev); \
344 return sprintf(buf, "%d (%d rpm)\n", \
345 th->last_speed[data], \
346 read_fan_speed(th, FAN_SPEED[data]) \
350 #define BUILD_STORE_FUNC_DEG(name, data) \
351 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
353 struct thermostat *th = dev_get_drvdata(dev); \
356 val = simple_strtol(buf, NULL, 10); \
357 printk(KERN_INFO "Adjusting limits by %d degrees\n", val); \
358 limit_adjust = val; \
359 for (i=0; i < 3; i++) \
364 #define BUILD_STORE_FUNC_INT(name, data) \
365 static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
368 val = simple_strtol(buf, NULL, 10); \
369 if (val < 0 || val > 255) \
371 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
376 BUILD_SHOW_FUNC_INT(sensor1_temperature
, (read_reg(th
, TEMP_REG
[1])))
377 BUILD_SHOW_FUNC_INT(sensor2_temperature
, (read_reg(th
, TEMP_REG
[2])))
378 BUILD_SHOW_FUNC_INT(sensor1_limit
, th
->limits
[1])
379 BUILD_SHOW_FUNC_INT(sensor2_limit
, th
->limits
[2])
380 BUILD_SHOW_FUNC_STR(sensor1_location
, sensor_location
[1])
381 BUILD_SHOW_FUNC_STR(sensor2_location
, sensor_location
[2])
383 BUILD_SHOW_FUNC_INT_LITE(specified_fan_speed
, fan_speed
)
384 BUILD_STORE_FUNC_INT(specified_fan_speed
,fan_speed
)
386 BUILD_SHOW_FUNC_FAN(sensor1_fan_speed
, 0)
387 BUILD_SHOW_FUNC_FAN(sensor2_fan_speed
, 1)
389 BUILD_SHOW_FUNC_INT_LITE(limit_adjust
, limit_adjust
)
390 BUILD_STORE_FUNC_DEG(limit_adjust
, th
)
392 static DEVICE_ATTR(sensor1_temperature
, S_IRUGO
,
393 show_sensor1_temperature
,NULL
);
394 static DEVICE_ATTR(sensor2_temperature
, S_IRUGO
,
395 show_sensor2_temperature
,NULL
);
396 static DEVICE_ATTR(sensor1_limit
, S_IRUGO
,
397 show_sensor1_limit
, NULL
);
398 static DEVICE_ATTR(sensor2_limit
, S_IRUGO
,
399 show_sensor2_limit
, NULL
);
400 static DEVICE_ATTR(sensor1_location
, S_IRUGO
,
401 show_sensor1_location
, NULL
);
402 static DEVICE_ATTR(sensor2_location
, S_IRUGO
,
403 show_sensor2_location
, NULL
);
405 static DEVICE_ATTR(specified_fan_speed
, S_IRUSR
|S_IWUSR
|S_IRGRP
|S_IROTH
,
406 show_specified_fan_speed
,store_specified_fan_speed
);
408 static DEVICE_ATTR(sensor1_fan_speed
, S_IRUGO
,
409 show_sensor1_fan_speed
, NULL
);
410 static DEVICE_ATTR(sensor2_fan_speed
, S_IRUGO
,
411 show_sensor2_fan_speed
, NULL
);
413 static DEVICE_ATTR(limit_adjust
, S_IRUSR
|S_IWUSR
|S_IRGRP
|S_IROTH
,
414 show_limit_adjust
, store_limit_adjust
);
416 static void thermostat_create_files(struct thermostat
*th
)
418 struct device_node
*np
= th
->clt
->dev
.of_node
;
422 /* To maintain ABI compatibility with userspace, create
423 * the old style platform driver and attach the attributes
426 th
->pdev
= of_platform_device_create(np
, "temperatures", NULL
);
429 dev
= &th
->pdev
->dev
;
430 dev_set_drvdata(dev
, th
);
431 err
= device_create_file(dev
, &dev_attr_sensor1_temperature
);
432 err
|= device_create_file(dev
, &dev_attr_sensor2_temperature
);
433 err
|= device_create_file(dev
, &dev_attr_sensor1_limit
);
434 err
|= device_create_file(dev
, &dev_attr_sensor2_limit
);
435 err
|= device_create_file(dev
, &dev_attr_sensor1_location
);
436 err
|= device_create_file(dev
, &dev_attr_sensor2_location
);
437 err
|= device_create_file(dev
, &dev_attr_limit_adjust
);
438 err
|= device_create_file(dev
, &dev_attr_specified_fan_speed
);
439 err
|= device_create_file(dev
, &dev_attr_sensor1_fan_speed
);
440 if(th
->type
== ADT7460
)
441 err
|= device_create_file(dev
, &dev_attr_sensor2_fan_speed
);
444 "Failed to create temperature attribute file(s).\n");
447 static void thermostat_remove_files(struct thermostat
*th
)
453 dev
= &th
->pdev
->dev
;
454 device_remove_file(dev
, &dev_attr_sensor1_temperature
);
455 device_remove_file(dev
, &dev_attr_sensor2_temperature
);
456 device_remove_file(dev
, &dev_attr_sensor1_limit
);
457 device_remove_file(dev
, &dev_attr_sensor2_limit
);
458 device_remove_file(dev
, &dev_attr_sensor1_location
);
459 device_remove_file(dev
, &dev_attr_sensor2_location
);
460 device_remove_file(dev
, &dev_attr_limit_adjust
);
461 device_remove_file(dev
, &dev_attr_specified_fan_speed
);
462 device_remove_file(dev
, &dev_attr_sensor1_fan_speed
);
463 if (th
->type
== ADT7460
)
464 device_remove_file(dev
, &dev_attr_sensor2_fan_speed
);
465 of_device_unregister(th
->pdev
);
469 static int probe_thermostat(struct i2c_client
*client
)
471 const struct i2c_device_id
*id
= i2c_client_get_device_id(client
);
472 struct device_node
*np
= client
->dev
.of_node
;
473 struct thermostat
* th
;
475 int i
, rc
, vers
, offset
= 0;
479 prop
= of_get_property(np
, "hwsensor-params-version", NULL
);
482 vers
= be32_to_cpup(prop
);
483 printk(KERN_INFO
"adt746x: version %d (%ssupported)\n",
484 vers
, vers
== 1 ? "" : "un");
488 if (of_property_present(np
, "hwsensor-location")) {
489 for (i
= 0; i
< 3; i
++) {
490 sensor_location
[i
] = of_get_property(np
,
491 "hwsensor-location", NULL
) + offset
;
493 if (sensor_location
[i
] == NULL
)
494 sensor_location
[i
] = "";
496 printk(KERN_INFO
"sensor %d: %s\n", i
, sensor_location
[i
]);
497 offset
+= strlen(sensor_location
[i
]) + 1;
501 th
= kzalloc(sizeof(struct thermostat
), GFP_KERNEL
);
505 i2c_set_clientdata(client
, th
);
507 th
->type
= id
->driver_data
;
509 rc
= read_reg(th
, CONFIG_REG
);
511 dev_err(&client
->dev
, "Thermostat failed to read config!\n");
516 /* force manual control to start the fan quieter */
520 if (th
->type
== ADT7460
) {
521 printk(KERN_INFO
"adt746x: ADT7460 initializing\n");
522 /* The 7460 needs to be started explicitly */
523 write_reg(th
, CONFIG_REG
, 1);
525 printk(KERN_INFO
"adt746x: ADT7467 initializing\n");
527 for (i
= 0; i
< 3; i
++) {
528 th
->initial_limits
[i
] = read_reg(th
, LIMIT_REG
[i
]);
532 printk(KERN_INFO
"adt746x: Lowering max temperatures from %d, %d, %d"
534 th
->initial_limits
[0], th
->initial_limits
[1],
535 th
->initial_limits
[2], th
->limits
[0], th
->limits
[1],
538 /* record invert bit status because fw can corrupt it after suspend */
539 th
->pwm_inv
[0] = read_reg(th
, MANUAL_MODE
[0]) & INVERT_MASK
;
540 th
->pwm_inv
[1] = read_reg(th
, MANUAL_MODE
[1]) & INVERT_MASK
;
542 /* be sure to really write fan speed the first time */
543 th
->last_speed
[0] = -2;
544 th
->last_speed
[1] = -2;
545 th
->last_var
[0] = -80;
546 th
->last_var
[1] = -80;
548 if (fan_speed
!= -1) {
549 /* manual mode, stop fans */
550 write_both_fan_speed(th
, 0);
553 write_both_fan_speed(th
, -1);
556 th
->thread
= kthread_run(monitor_task
, th
, "kfand");
557 if (th
->thread
== ERR_PTR(-ENOMEM
)) {
558 printk(KERN_INFO
"adt746x: Kthread creation failed\n");
563 thermostat_create_files(th
);
568 static void remove_thermostat(struct i2c_client
*client
)
570 struct thermostat
*th
= i2c_get_clientdata(client
);
573 thermostat_remove_files(th
);
575 if (th
->thread
!= NULL
)
576 kthread_stop(th
->thread
);
578 printk(KERN_INFO
"adt746x: Putting max temperatures back from "
579 "%d, %d, %d to %d, %d, %d\n",
580 th
->limits
[0], th
->limits
[1], th
->limits
[2],
581 th
->initial_limits
[0], th
->initial_limits
[1],
582 th
->initial_limits
[2]);
584 for (i
= 0; i
< 3; i
++)
585 write_reg(th
, LIMIT_REG
[i
], th
->initial_limits
[i
]);
587 write_both_fan_speed(th
, -1);
592 static const struct i2c_device_id therm_adt746x_id
[] = {
593 { "MAC,adt7460", ADT7460
},
594 { "MAC,adt7467", ADT7467
},
597 MODULE_DEVICE_TABLE(i2c
, therm_adt746x_id
);
599 static struct i2c_driver thermostat_driver
= {
601 .name
= "therm_adt746x",
603 .probe
= probe_thermostat
,
604 .remove
= remove_thermostat
,
605 .id_table
= therm_adt746x_id
,
608 static int __init
thermostat_init(void)
610 #ifndef CONFIG_I2C_POWERMAC
611 request_module("i2c-powermac");
614 return i2c_add_driver(&thermostat_driver
);
617 static void __exit
thermostat_exit(void)
619 i2c_del_driver(&thermostat_driver
);
622 module_init(thermostat_init
);
623 module_exit(thermostat_exit
);