therm_adt746x.c
/*
* Device driver for the i2c thermostat found on the iBook G4, Albook G4
*
* Copyright (C) 2003, 2004 Colin Leroy, Rasmus Rohde, Benjamin Herrenschmidt
*
* Documentation from
* http://www.analog.com/UploadedFiles/Data_Sheets/115254175ADT7467_pra.pdf
* http://www.analog.com/UploadedFiles/Data_Sheets/3686221171167ADT7460_b.pdf
*
*/
#include <linux/types.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/suspend.h>
#include <linux/kthread.h>
#include <linux/moduleparam.h>
#include <linux/freezer.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/sections.h>
#include <asm/of_platform.h>
#undef DEBUG
#define CONFIG_REG 0x40
#define MANUAL_MASK 0xe0
#define AUTO_MASK 0x20
static u8 TEMP_REG[3] = {0x26, 0x25, 0x27}; /* local, sensor1, sensor2 */
static u8 LIMIT_REG[3] = {0x6b, 0x6a, 0x6c}; /* local, sensor1, sensor2 */
static u8 MANUAL_MODE[2] = {0x5c, 0x5d};
static u8 REM_CONTROL[2] = {0x00, 0x40};
static u8 FAN_SPEED[2] = {0x28, 0x2a};
static u8 FAN_SPD_SET[2] = {0x30, 0x31};
static u8 default_limits_local[3] = {70, 50, 70}; /* local, sensor1, sensor2 */
static u8 default_limits_chip[3] = {80, 65, 80}; /* local, sensor1, sensor2 */
static const char *sensor_location[3];
static int limit_adjust;
static int fan_speed = -1;
static int verbose;
MODULE_AUTHOR("Colin Leroy <colin@colino.net>");
MODULE_DESCRIPTION("Driver for ADT746x thermostat in iBook G4 and "
"Powerbook G4 Alu");
MODULE_LICENSE("GPL");
module_param(limit_adjust, int, 0644);
MODULE_PARM_DESC(limit_adjust,"Adjust maximum temperatures (50 sensor1, 70 sensor2) "
"by N degrees.");
module_param(fan_speed, int, 0644);
MODULE_PARM_DESC(fan_speed,"Specify starting fan speed (0-255) "
"(default 64)");
module_param(verbose, bool, 0);
MODULE_PARM_DESC(verbose,"Verbose log operations "
"(default 0)");
struct thermostat {
struct i2c_client clt;
u8 temps[3];
u8 cached_temp[3];
u8 initial_limits[3];
u8 limits[3];
int last_speed[2];
int last_var[2];
};
static enum {ADT7460, ADT7467} therm_type;
static int therm_bus, therm_address;
static struct of_device * of_dev;
static struct thermostat* thermostat;
static struct task_struct *thread_therm = NULL;
static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
int busno);
static void write_both_fan_speed(struct thermostat *th, int speed);
static void write_fan_speed(struct thermostat *th, int speed, int fan);
static int
write_reg(struct thermostat* th, int reg, u8 data)
{
u8 tmp[2];
int rc;
tmp[0] = reg;
tmp[1] = data;
rc = i2c_master_send(&th->clt, (const char *)tmp, 2);
if (rc < 0)
return rc;
if (rc != 2)
return -ENODEV;
return 0;
}
static int
read_reg(struct thermostat* th, int reg)
{
u8 reg_addr, data;
int rc;
reg_addr = (u8)reg;
rc = i2c_master_send(&th->clt, ®_addr, 1);
if (rc < 0)
return rc;
if (rc != 1)
return -ENODEV;
rc = i2c_master_recv(&th->clt, (char *)&data, 1);
if (rc < 0)
return rc;
return data;
}
static int
attach_thermostat(struct i2c_adapter *adapter)
{
unsigned long bus_no;
if (strncmp(adapter->name, "uni-n", 5))
return -ENODEV;
bus_no = simple_strtoul(adapter->name + 6, NULL, 10);
if (bus_no != therm_bus)
return -ENODEV;
return attach_one_thermostat(adapter, therm_address, bus_no);
}
static int
detach_thermostat(struct i2c_adapter *adapter)
{
struct thermostat* th;
int i;
if (thermostat == NULL)
return 0;
th = thermostat;
if (thread_therm != NULL) {
kthread_stop(thread_therm);
}
printk(KERN_INFO "adt746x: Putting max temperatures back from "
"%d, %d, %d to %d, %d, %d\n",
th->limits[0], th->limits[1], th->limits[2],
th->initial_limits[0], th->initial_limits[1],
th->initial_limits[2]);
for (i = 0; i < 3; i++)
write_reg(th, LIMIT_REG[i], th->initial_limits[i]);
write_both_fan_speed(th, -1);
i2c_detach_client(&th->clt);
thermostat = NULL;
kfree(th);
return 0;
}
static struct i2c_driver thermostat_driver = {
.driver = {
.name = "therm_adt746x",
},
.attach_adapter = attach_thermostat,
.detach_adapter = detach_thermostat,
};
static int read_fan_speed(struct thermostat *th, u8 addr)
{
u8 tmp[2];
u16 res;
/* should start with low byte */
tmp[1] = read_reg(th, addr);
tmp[0] = read_reg(th, addr + 1);
res = tmp[1] + (tmp[0] << 8);
/* "a value of 0xffff means that the fan has stopped" */
return (res == 0xffff ? 0 : (90000*60)/res);
}
static void write_both_fan_speed(struct thermostat *th, int speed)
{
write_fan_speed(th, speed, 0);
if (therm_type == ADT7460)
write_fan_speed(th, speed, 1);
}
static void write_fan_speed(struct thermostat *th, int speed, int fan)
{
u8 manual;
if (speed > 0xff)
speed = 0xff;
else if (speed < -1)
speed = 0;
if (therm_type == ADT7467 && fan == 1)
return;
if (th->last_speed[fan] != speed) {
if (verbose) {
if (speed == -1)
printk(KERN_DEBUG "adt746x: Setting speed to automatic "
"for %s fan.\n", sensor_location[fan+1]);
else
printk(KERN_DEBUG "adt746x: Setting speed to %d "
"for %s fan.\n", speed, sensor_location[fan+1]);
}
} else
return;
if (speed >= 0) {
manual = read_reg(th, MANUAL_MODE[fan]);
write_reg(th, MANUAL_MODE[fan], manual|MANUAL_MASK);
write_reg(th, FAN_SPD_SET[fan], speed);
} else {
/* back to automatic */
if(therm_type == ADT7460) {
manual = read_reg(th,
MANUAL_MODE[fan]) & (~MANUAL_MASK);
write_reg(th,
MANUAL_MODE[fan], manual|REM_CONTROL[fan]);
} else {
manual = read_reg(th, MANUAL_MODE[fan]);
write_reg(th, MANUAL_MODE[fan], manual&(~AUTO_MASK));
}
}
th->last_speed[fan] = speed;
}
static void read_sensors(struct thermostat *th)
{
int i = 0;
for (i = 0; i < 3; i++)
th->temps[i] = read_reg(th, TEMP_REG[i]);
}
#ifdef DEBUG
static void display_stats(struct thermostat *th)
{
if (th->temps[0] != th->cached_temp[0]
|| th->temps[1] != th->cached_temp[1]
|| th->temps[2] != th->cached_temp[2]) {
printk(KERN_INFO "adt746x: Temperature infos:"
" thermostats: %d,%d,%d;"
" limits: %d,%d,%d;"
" fan speed: %d RPM\n",
th->temps[0], th->temps[1], th->temps[2],
th->limits[0], th->limits[1], th->limits[2],
read_fan_speed(th, FAN_SPEED[0]));
}
th->cached_temp[0] = th->temps[0];
th->cached_temp[1] = th->temps[1];
th->cached_temp[2] = th->temps[2];
}
#endif
static void update_fans_speed (struct thermostat *th)
{
int lastvar = 0; /* last variation, for iBook */
int i = 0;
/* we don't care about local sensor, so we start at sensor 1 */
for (i = 1; i < 3; i++) {
int started = 0;
int fan_number = (therm_type == ADT7460 && i == 2);
int var = th->temps[i] - th->limits[i];
if (var > -1) {
int step = (255 - fan_speed) / 7;
int new_speed = 0;
/* hysteresis : change fan speed only if variation is
* more than two degrees */
if (abs(var - th->last_var[fan_number]) < 2)
continue;
started = 1;
new_speed = fan_speed + ((var-1)*step);
if (new_speed < fan_speed)
new_speed = fan_speed;
if (new_speed > 255)
new_speed = 255;
if (verbose)
printk(KERN_DEBUG "adt746x: Setting fans speed to %d "
"(limit exceeded by %d on %s) \n",
new_speed, var,
sensor_location[fan_number+1]);
write_both_fan_speed(th, new_speed);
th->last_var[fan_number] = var;
} else if (var < -2) {
/* don't stop fan if sensor2 is cold and sensor1 is not
* so cold (lastvar >= -1) */
if (i == 2 && lastvar < -1) {
if (th->last_speed[fan_number] != 0)
if (verbose)
printk(KERN_DEBUG "adt746x: Stopping "
"fans.\n");
write_both_fan_speed(th, 0);
}
}
lastvar = var;
if (started)
return; /* we don't want to re-stop the fan
* if sensor1 is heating and sensor2 is not */
}
}
static int monitor_task(void *arg)
{
struct thermostat* th = arg;
set_freezable();
while(!kthread_should_stop()) {
try_to_freeze();
msleep_interruptible(2000);
#ifndef DEBUG
if (fan_speed != -1)
read_sensors(th);
#else
read_sensors(th);
#endif
if (fan_speed != -1)
update_fans_speed(th);
#ifdef DEBUG
display_stats(th);
#endif
}
return 0;
}
static void set_limit(struct thermostat *th, int i)
{
/* Set sensor1 limit higher to avoid powerdowns */
th->limits[i] = default_limits_chip[i] + limit_adjust;
write_reg(th, LIMIT_REG[i], th->limits[i]);
/* set our limits to normal */
th->limits[i] = default_limits_local[i] + limit_adjust;
}
static int attach_one_thermostat(struct i2c_adapter *adapter, int addr,
int busno)
{
struct thermostat* th;
int rc;
int i;
if (thermostat)
return 0;
th = kzalloc(sizeof(struct thermostat), GFP_KERNEL);
if (!th)
return -ENOMEM;
th->clt.addr = addr;
th->clt.adapter = adapter;
th->clt.driver = &thermostat_driver;
strcpy(th->clt.name, "thermostat");
rc = read_reg(th, 0);
if (rc < 0) {
printk(KERN_ERR "adt746x: Thermostat failed to read config "
"from bus %d !\n",
busno);
kfree(th);
return -ENODEV;
}
/* force manual control to start the fan quieter */
if (fan_speed == -1)
fan_speed = 64;
if(therm_type == ADT7460) {
printk(KERN_INFO "adt746x: ADT7460 initializing\n");
/* The 7460 needs to be started explicitly */
write_reg(th, CONFIG_REG, 1);
} else
printk(KERN_INFO "adt746x: ADT7467 initializing\n");
for (i = 0; i < 3; i++) {
th->initial_limits[i] = read_reg(th, LIMIT_REG[i]);
set_limit(th, i);
}
printk(KERN_INFO "adt746x: Lowering max temperatures from %d, %d, %d"
" to %d, %d, %d\n",
th->initial_limits[0], th->initial_limits[1],
th->initial_limits[2], th->limits[0], th->limits[1],
th->limits[2]);
thermostat = th;
if (i2c_attach_client(&th->clt)) {
printk(KERN_INFO "adt746x: Thermostat failed to attach "
"client !\n");
thermostat = NULL;
kfree(th);
return -ENODEV;
}
/* be sure to really write fan speed the first time */
th->last_speed[0] = -2;
th->last_speed[1] = -2;
th->last_var[0] = -80;
th->last_var[1] = -80;
if (fan_speed != -1) {
/* manual mode, stop fans */
write_both_fan_speed(th, 0);
} else {
/* automatic mode */
write_both_fan_speed(th, -1);
}
thread_therm = kthread_run(monitor_task, th, "kfand");
if (thread_therm == ERR_PTR(-ENOMEM)) {
printk(KERN_INFO "adt746x: Kthread creation failed\n");
thread_therm = NULL;
return -ENOMEM;
}
return 0;
}
/*
* Now, unfortunately, sysfs doesn't give us a nice void * we could
* pass around to the attribute functions, so we don't really have
* choice but implement a bunch of them...
*
* FIXME, it does now...
*/
#define BUILD_SHOW_FUNC_INT(name, data) \
static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%d\n", data); \
}
#define BUILD_SHOW_FUNC_STR(name, data) \
static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%s\n", data); \
}
#define BUILD_SHOW_FUNC_FAN(name, data) \
static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
return sprintf(buf, "%d (%d rpm)\n", \
thermostat->last_speed[data], \
read_fan_speed(thermostat, FAN_SPEED[data]) \
); \
}
#define BUILD_STORE_FUNC_DEG(name, data) \
static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
{ \
int val; \
int i; \
val = simple_strtol(buf, NULL, 10); \
printk(KERN_INFO "Adjusting limits by %d degrees\n", val); \
limit_adjust = val; \
for (i=0; i < 3; i++) \
set_limit(thermostat, i); \
return n; \
}
#define BUILD_STORE_FUNC_INT(name, data) \
static ssize_t store_##name(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) \
{ \
u32 val; \
val = simple_strtoul(buf, NULL, 10); \
if (val < 0 || val > 255) \
return -EINVAL; \
printk(KERN_INFO "Setting specified fan speed to %d\n", val); \
data = val; \
return n; \
}
BUILD_SHOW_FUNC_INT(sensor1_temperature, (read_reg(thermostat, TEMP_REG[1])))
BUILD_SHOW_FUNC_INT(sensor2_temperature, (read_reg(thermostat, TEMP_REG[2])))
BUILD_SHOW_FUNC_INT(sensor1_limit, thermostat->limits[1])
BUILD_SHOW_FUNC_INT(sensor2_limit, thermostat->limits[2])
BUILD_SHOW_FUNC_STR(sensor1_location, sensor_location[1])
BUILD_SHOW_FUNC_STR(sensor2_location, sensor_location[2])
BUILD_SHOW_FUNC_INT(specified_fan_speed, fan_speed)
BUILD_SHOW_FUNC_FAN(sensor1_fan_speed, 0)
BUILD_SHOW_FUNC_FAN(sensor2_fan_speed, 1)
BUILD_STORE_FUNC_INT(specified_fan_speed,fan_speed)
BUILD_SHOW_FUNC_INT(limit_adjust, limit_adjust)
BUILD_STORE_FUNC_DEG(limit_adjust, thermostat)
static DEVICE_ATTR(sensor1_temperature, S_IRUGO,
show_sensor1_temperature,NULL);
static DEVICE_ATTR(sensor2_temperature, S_IRUGO,
show_sensor2_temperature,NULL);
static DEVICE_ATTR(sensor1_limit, S_IRUGO,
show_sensor1_limit, NULL);
static DEVICE_ATTR(sensor2_limit, S_IRUGO,
show_sensor2_limit, NULL);
static DEVICE_ATTR(sensor1_location, S_IRUGO,
show_sensor1_location, NULL);
static DEVICE_ATTR(sensor2_location, S_IRUGO,
show_sensor2_location, NULL);
static DEVICE_ATTR(specified_fan_speed, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
show_specified_fan_speed,store_specified_fan_speed);
static DEVICE_ATTR(sensor1_fan_speed, S_IRUGO,
show_sensor1_fan_speed, NULL);
static DEVICE_ATTR(sensor2_fan_speed, S_IRUGO,
show_sensor2_fan_speed, NULL);
static DEVICE_ATTR(limit_adjust, S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH,
show_limit_adjust, store_limit_adjust);
static int __init
thermostat_init(void)
{
struct device_node* np;
const u32 *prop;
int i = 0, offset = 0;
int err;
np = of_find_node_by_name(NULL, "fan");
if (!np)
return -ENODEV;
if (of_device_is_compatible(np, "adt7460"))
therm_type = ADT7460;
else if (of_device_is_compatible(np, "adt7467"))
therm_type = ADT7467;
else {
of_node_put(np);
return -ENODEV;
}
prop = of_get_property(np, "hwsensor-params-version", NULL);
printk(KERN_INFO "adt746x: version %d (%ssupported)\n", *prop,
(*prop == 1)?"":"un");
if (*prop != 1) {
of_node_put(np);
return -ENODEV;
}
prop = of_get_property(np, "reg", NULL);
if (!prop) {
of_node_put(np);
return -ENODEV;
}
/* look for bus either by path or using "reg" */
if (strstr(np->full_name, "/i2c-bus@") != NULL) {
const char *tmp_bus = (strstr(np->full_name, "/i2c-bus@") + 9);
therm_bus = tmp_bus[0]-'0';
} else {
therm_bus = ((*prop) >> 8) & 0x0f;
}
therm_address = ((*prop) & 0xff) >> 1;
printk(KERN_INFO "adt746x: Thermostat bus: %d, address: 0x%02x, "
"limit_adjust: %d, fan_speed: %d\n",
therm_bus, therm_address, limit_adjust, fan_speed);
if (of_get_property(np, "hwsensor-location", NULL)) {
for (i = 0; i < 3; i++) {
sensor_location[i] = of_get_property(np,
"hwsensor-location", NULL) + offset;
if (sensor_location[i] == NULL)
sensor_location[i] = "";
printk(KERN_INFO "sensor %d: %s\n", i, sensor_location[i]);
offset += strlen(sensor_location[i]) + 1;
}
} else {
sensor_location[0] = "?";
sensor_location[1] = "?";
sensor_location[2] = "?";
}
of_dev = of_platform_device_create(np, "temperatures", NULL);
if (of_dev == NULL) {
printk(KERN_ERR "Can't register temperatures device !\n");
of_node_put(np);
return -ENODEV;
}
err = device_create_file(&of_dev->dev, &dev_attr_sensor1_temperature);
err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_temperature);
err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_limit);
err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_limit);
err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_location);
err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_location);
err |= device_create_file(&of_dev->dev, &dev_attr_limit_adjust);
err |= device_create_file(&of_dev->dev, &dev_attr_specified_fan_speed);
err |= device_create_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
if(therm_type == ADT7460)
err |= device_create_file(&of_dev->dev, &dev_attr_sensor2_fan_speed);
if (err)
printk(KERN_WARNING
"Failed to create tempertaure attribute file(s).\n");
#ifndef CONFIG_I2C_POWERMAC
request_module("i2c-powermac");
#endif
return i2c_add_driver(&thermostat_driver);
}
static void __exit
thermostat_exit(void)
{
if (of_dev) {
device_remove_file(&of_dev->dev, &dev_attr_sensor1_temperature);
device_remove_file(&of_dev->dev, &dev_attr_sensor2_temperature);
device_remove_file(&of_dev->dev, &dev_attr_sensor1_limit);
device_remove_file(&of_dev->dev, &dev_attr_sensor2_limit);
device_remove_file(&of_dev->dev, &dev_attr_sensor1_location);
device_remove_file(&of_dev->dev, &dev_attr_sensor2_location);
device_remove_file(&of_dev->dev, &dev_attr_limit_adjust);
device_remove_file(&of_dev->dev, &dev_attr_specified_fan_speed);
device_remove_file(&of_dev->dev, &dev_attr_sensor1_fan_speed);
if(therm_type == ADT7460)
device_remove_file(&of_dev->dev,
&dev_attr_sensor2_fan_speed);
of_device_unregister(of_dev);
}
i2c_del_driver(&thermostat_driver);
}
module_init(thermostat_init);
module_exit(thermostat_exit);