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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Device driver for the i2c thermostat found on the iBook G4, Albook G44 *5 * Copyright (C) 2003, 2004 Colin Leroy, Rasmus Rohde, Benjamin Herrenschmidt6 *7 * Documentation from 115254175ADT7467_pra.pdf and 3686221171167ADT7460_b.pdf8 * https://www.onsemi.com/PowerSolutions/product.do?id=ADT74679 * https://www.onsemi.com/PowerSolutions/product.do?id=ADT746010 *11 */12 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.h>29#include <linux/of_platform.h>30#include <linux/platform_device.h>31 32#include <asm/machdep.h>33#include <asm/io.h>34#include <asm/sections.h>35 36#undef DEBUG37 38#define CONFIG_REG 0x4039#define MANUAL_MASK 0xe040#define AUTO_MASK 0x2041#define INVERT_MASK 0x1042 43static u8 TEMP_REG[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */44static u8 LIMIT_REG[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */45static u8 MANUAL_MODE[2] = {0x5c, 0x5d}; 46static u8 REM_CONTROL[2] = {0x00, 0x40};47static u8 FAN_SPEED[2] = {0x28, 0x2a};48static u8 FAN_SPD_SET[2] = {0x30, 0x31};49 50static u8 default_limits_local[3] = {70, 50, 70}; /* local, sensor1, sensor2 */51static u8 default_limits_chip[3] = {80, 65, 80}; /* local, sensor1, sensor2 */52static const char *sensor_location[3] = { "?", "?", "?" };53 54static int limit_adjust;55static int fan_speed = -1;56static bool verbose;57 58MODULE_AUTHOR("Colin Leroy <colin@colino.net>");59MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "60 "Powerbook G4 Alu");61MODULE_LICENSE("GPL");62 63module_param(limit_adjust, int, 0644);64MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "65 "by N degrees.");66 67module_param(fan_speed, int, 0644);68MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "69 "(default 64)");70 71module_param(verbose, bool, 0);72MODULE_PARM_DESC(verbose,"Verbose log operations "73 "(default 0)");74 75struct thermostat {76 struct i2c_client *clt;77 u8 temps[3];78 u8 cached_temp[3];79 u8 initial_limits[3];80 u8 limits[3];81 int last_speed[2];82 int last_var[2];83 int pwm_inv[2];84 struct task_struct *thread;85 struct platform_device *pdev;86 enum {87 ADT7460,88 ADT746789 } type;90};91 92static void write_both_fan_speed(struct thermostat *th, int speed);93static void write_fan_speed(struct thermostat *th, int speed, int fan);94 95static int96write_reg(struct thermostat* th, int reg, u8 data)97{98 u8 tmp[2];99 int rc;100 101 tmp[0] = reg;102 tmp[1] = data;103 rc = i2c_master_send(th->clt, (const char *)tmp, 2);104 if (rc < 0)105 return rc;106 if (rc != 2)107 return -ENODEV;108 return 0;109}110 111static int112read_reg(struct thermostat* th, int reg)113{114 u8 reg_addr, data;115 int rc;116 117 reg_addr = (u8)reg;118 rc = i2c_master_send(th->clt, ®_addr, 1);119 if (rc < 0)120 return rc;121 if (rc != 1)122 return -ENODEV;123 rc = i2c_master_recv(th->clt, (char *)&data, 1);124 if (rc < 0)125 return rc;126 return data;127}128 129static int read_fan_speed(struct thermostat *th, u8 addr)130{131 u8 tmp[2];132 u16 res;133 134 /* should start with low byte */135 tmp[1] = read_reg(th, addr);136 tmp[0] = read_reg(th, addr + 1);137 138 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);141}142 143static void write_both_fan_speed(struct thermostat *th, int speed)144{145 write_fan_speed(th, speed, 0);146 if (th->type == ADT7460)147 write_fan_speed(th, speed, 1);148}149 150static void write_fan_speed(struct thermostat *th, int speed, int fan)151{152 u8 manual;153 154 if (speed > 0xff) 155 speed = 0xff;156 else if (speed < -1) 157 speed = 0;158 159 if (th->type == ADT7467 && fan == 1)160 return;161 162 if (th->last_speed[fan] != speed) {163 if (verbose) {164 if (speed == -1)165 printk(KERN_DEBUG "adt746x: Setting speed to automatic "166 "for %s fan.\n", sensor_location[fan+1]);167 else168 printk(KERN_DEBUG "adt746x: Setting speed to %d "169 "for %s fan.\n", speed, sensor_location[fan+1]);170 }171 } else172 return;173 174 if (speed >= 0) {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);180 } else {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];187 write_reg(th,188 MANUAL_MODE[fan], manual|REM_CONTROL[fan]);189 } else {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));194 }195 }196 197 th->last_speed[fan] = speed; 198}199 200static void read_sensors(struct thermostat *th)201{202 int i = 0;203 204 for (i = 0; i < 3; i++)205 th->temps[i] = read_reg(th, TEMP_REG[i]);206}207 208#ifdef DEBUG209static void display_stats(struct thermostat *th)210{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;"216 " limits: %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]));221 }222 th->cached_temp[0] = th->temps[0];223 th->cached_temp[1] = th->temps[1];224 th->cached_temp[2] = th->temps[2];225}226#endif227 228static void update_fans_speed (struct thermostat *th)229{230 int lastvar = 0; /* last variation, for iBook */231 int i = 0;232 233 /* 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];238 239 if (var > -1) {240 int step = (255 - fan_speed) / 7;241 int new_speed = 0;242 243 /* hysteresis : change fan speed only if variation is244 * more than two degrees */245 if (abs(var - th->last_var[fan_number]) < 2)246 continue;247 248 started = true;249 new_speed = fan_speed + ((var-1)*step);250 251 if (new_speed < fan_speed)252 new_speed = fan_speed;253 if (new_speed > 255)254 new_speed = 255;255 256 if (verbose)257 printk(KERN_DEBUG "adt746x: Setting fans speed to %d "258 "(limit exceeded by %d on %s)\n",259 new_speed, var,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 not265 * so cold (lastvar >= -1) */266 if (i == 2 && lastvar < -1) {267 if (th->last_speed[fan_number] != 0)268 if (verbose)269 printk(KERN_DEBUG "adt746x: Stopping "270 "fans.\n");271 write_both_fan_speed(th, 0);272 }273 }274 275 lastvar = var;276 277 if (started)278 return; /* we don't want to re-stop the fan279 * if sensor1 is heating and sensor2 is not */280 }281}282 283static int monitor_task(void *arg)284{285 struct thermostat* th = arg;286 287 set_freezable();288 while(!kthread_should_stop()) {289 try_to_freeze();290 msleep_interruptible(2000);291 292#ifndef DEBUG293 if (fan_speed != -1)294 read_sensors(th);295#else296 read_sensors(th);297#endif 298 299 if (fan_speed != -1)300 update_fans_speed(th);301 302#ifdef DEBUG303 display_stats(th);304#endif305 306 }307 308 return 0;309}310 311static void set_limit(struct thermostat *th, int i)312{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]);316 317 /* set our limits to normal */318 th->limits[i] = default_limits_local[i] + limit_adjust;319}320 321#define BUILD_SHOW_FUNC_INT(name, data) \322static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \323{ \324 struct thermostat *th = dev_get_drvdata(dev); \325 return sprintf(buf, "%d\n", data); \326}327 328#define BUILD_SHOW_FUNC_INT_LITE(name, data) \329static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \330{ \331 return sprintf(buf, "%d\n", data); \332}333 334#define BUILD_SHOW_FUNC_STR(name, data) \335static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \336{ \337 return sprintf(buf, "%s\n", data); \338}339 340#define BUILD_SHOW_FUNC_FAN(name, data) \341static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \342{ \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]) \347 ); \348}349 350#define BUILD_STORE_FUNC_DEG(name, data) \351static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \352{ \353 struct thermostat *th = dev_get_drvdata(dev); \354 int val; \355 int i; \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++) \360 set_limit(th, i); \361 return n; \362}363 364#define BUILD_STORE_FUNC_INT(name, data) \365static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \366{ \367 int val; \368 val = simple_strtol(buf, NULL, 10); \369 if (val < 0 || val > 255) \370 return -EINVAL; \371 printk(KERN_INFO "Setting specified fan speed to %d\n", val); \372 data = val; \373 return n; \374}375 376BUILD_SHOW_FUNC_INT(sensor1_temperature, (read_reg(th, TEMP_REG[1])))377BUILD_SHOW_FUNC_INT(sensor2_temperature, (read_reg(th, TEMP_REG[2])))378BUILD_SHOW_FUNC_INT(sensor1_limit, th->limits[1])379BUILD_SHOW_FUNC_INT(sensor2_limit, th->limits[2])380BUILD_SHOW_FUNC_STR(sensor1_location, sensor_location[1])381BUILD_SHOW_FUNC_STR(sensor2_location, sensor_location[2])382 383BUILD_SHOW_FUNC_INT_LITE(specified_fan_speed, fan_speed)384BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)385 386BUILD_SHOW_FUNC_FAN(sensor1_fan_speed, 0)387BUILD_SHOW_FUNC_FAN(sensor2_fan_speed, 1)388 389BUILD_SHOW_FUNC_INT_LITE(limit_adjust, limit_adjust)390BUILD_STORE_FUNC_DEG(limit_adjust, th)391 392static DEVICE_ATTR(sensor1_temperature, S_IRUGO,393 show_sensor1_temperature,NULL);394static DEVICE_ATTR(sensor2_temperature, S_IRUGO,395 show_sensor2_temperature,NULL);396static DEVICE_ATTR(sensor1_limit, S_IRUGO,397 show_sensor1_limit, NULL);398static DEVICE_ATTR(sensor2_limit, S_IRUGO,399 show_sensor2_limit, NULL);400static DEVICE_ATTR(sensor1_location, S_IRUGO,401 show_sensor1_location, NULL);402static DEVICE_ATTR(sensor2_location, S_IRUGO,403 show_sensor2_location, NULL);404 405static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,406 show_specified_fan_speed,store_specified_fan_speed);407 408static DEVICE_ATTR(sensor1_fan_speed, S_IRUGO,409 show_sensor1_fan_speed, NULL);410static DEVICE_ATTR(sensor2_fan_speed, S_IRUGO,411 show_sensor2_fan_speed, NULL);412 413static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,414 show_limit_adjust, store_limit_adjust);415 416static void thermostat_create_files(struct thermostat *th)417{418 struct device_node *np = th->clt->dev.of_node;419 struct device *dev;420 int err;421 422 /* To maintain ABI compatibility with userspace, create423 * the old style platform driver and attach the attributes424 * to it here425 */426 th->pdev = of_platform_device_create(np, "temperatures", NULL);427 if (!th->pdev)428 return;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);442 if (err)443 printk(KERN_WARNING444 "Failed to create temperature attribute file(s).\n");445}446 447static void thermostat_remove_files(struct thermostat *th)448{449 struct device *dev;450 451 if (!th->pdev)452 return;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);466 467}468 469static int probe_thermostat(struct i2c_client *client)470{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;474 const __be32 *prop;475 int i, rc, vers, offset = 0;476 477 if (!np)478 return -ENXIO;479 prop = of_get_property(np, "hwsensor-params-version", NULL);480 if (!prop)481 return -ENXIO;482 vers = be32_to_cpup(prop);483 printk(KERN_INFO "adt746x: version %d (%ssupported)\n",484 vers, vers == 1 ? "" : "un");485 if (vers != 1)486 return -ENXIO;487 488 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;492 493 if (sensor_location[i] == NULL)494 sensor_location[i] = "";495 496 printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);497 offset += strlen(sensor_location[i]) + 1;498 }499 }500 501 th = kzalloc(sizeof(struct thermostat), GFP_KERNEL);502 if (!th)503 return -ENOMEM;504 505 i2c_set_clientdata(client, th);506 th->clt = client;507 th->type = id->driver_data;508 509 rc = read_reg(th, CONFIG_REG);510 if (rc < 0) {511 dev_err(&client->dev, "Thermostat failed to read config!\n");512 kfree(th);513 return -ENODEV;514 }515 516 /* force manual control to start the fan quieter */517 if (fan_speed == -1)518 fan_speed = 64;519 520 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);524 } else525 printk(KERN_INFO "adt746x: ADT7467 initializing\n");526 527 for (i = 0; i < 3; i++) {528 th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);529 set_limit(th, i);530 }531 532 printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"533 " to %d, %d, %d\n",534 th->initial_limits[0], th->initial_limits[1],535 th->initial_limits[2], th->limits[0], th->limits[1],536 th->limits[2]);537 538 /* 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;541 542 /* 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;547 548 if (fan_speed != -1) {549 /* manual mode, stop fans */550 write_both_fan_speed(th, 0);551 } else {552 /* automatic mode */553 write_both_fan_speed(th, -1);554 }555 556 th->thread = kthread_run(monitor_task, th, "kfand");557 if (th->thread == ERR_PTR(-ENOMEM)) {558 printk(KERN_INFO "adt746x: Kthread creation failed\n");559 th->thread = NULL;560 return -ENOMEM;561 }562 563 thermostat_create_files(th);564 565 return 0;566}567 568static void remove_thermostat(struct i2c_client *client)569{570 struct thermostat *th = i2c_get_clientdata(client);571 int i;572 573 thermostat_remove_files(th);574 575 if (th->thread != NULL)576 kthread_stop(th->thread);577 578 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]);583 584 for (i = 0; i < 3; i++)585 write_reg(th, LIMIT_REG[i], th->initial_limits[i]);586 587 write_both_fan_speed(th, -1);588 589 kfree(th);590}591 592static const struct i2c_device_id therm_adt746x_id[] = {593 { "MAC,adt7460", ADT7460 },594 { "MAC,adt7467", ADT7467 },595 { }596};597MODULE_DEVICE_TABLE(i2c, therm_adt746x_id);598 599static struct i2c_driver thermostat_driver = {600 .driver = {601 .name = "therm_adt746x",602 },603 .probe = probe_thermostat,604 .remove = remove_thermostat,605 .id_table = therm_adt746x_id,606};607 608static int __init thermostat_init(void)609{610#ifndef CONFIG_I2C_POWERMAC611 request_module("i2c-powermac");612#endif613 614 return i2c_add_driver(&thermostat_driver);615}616 617static void __exit thermostat_exit(void)618{619 i2c_del_driver(&thermostat_driver);620}621 622module_init(thermostat_init);623module_exit(thermostat_exit);624