linux-imx

/* 

 *   Creation Date: <2003/03/14 20:54:13 samuel>

 *   Time-stamp: <2004/03/20 14:20:59 samuel>

 *   

 *  <therm_windtunnel.c>

 *  

 *  The G4 "windtunnel" has a single fan controlled by an

 *  ADM1030 fan controller and a DS1775 thermostat.

 *

 *  The fan controller is equipped with a temperature sensor

 *  which measures the case temperature. The DS1775 sensor

 *  measures the CPU temperature. This driver tunes the

 *  behavior of the fan. It is based upon empirical observations

 *  of the 'AppleFan' driver under Mac OS X.

 *

 *  WARNING: This driver has only been testen on Apple's

 *  1.25 MHz Dual G4 (March 03). It is tuned for a CPU

 *  temperature around 57 C.

 *

 *   Copyright (C) 2003, 2004 Samuel Rydh (samuel@ibrium.se)

 *

 *   Loosely based upon 'thermostat.c' written by Benjamin Herrenschmidt

 *   

 *   This program is free software; you can redistribute it and/or

 *   modify it under the terms of the GNU General Public License

 *   as published by the Free Software Foundation

 *   

 */

​

#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/init.h>

#include <linux/kthread.h>

#include <linux/of_platform.h>

​

#include <asm/prom.h>

#include <asm/machdep.h>

#include <asm/io.h>

#include <asm/sections.h>

#include <asm/macio.h>

​

#define LOG_TEMP        0           /* continuously log temperature */

​

static struct {

    volatile int        running;

    struct task_struct  *poll_task;

    struct mutex        lock;

    struct platform_device  *of_dev;

    struct i2c_client   *thermostat;

    struct i2c_client   *fan;

​

    int         overheat_temp;      /* 100% fan at this temp */

    int         overheat_hyst;

    int         temp;

    int         casetemp;

    int         fan_level;      /* active fan_table setting */

​

    int         downind;

    int         upind;

​

    int         r0, r1, r20, r23, r25;  /* saved register */

} x;

​

#define T(x,y)          (((x)<<8) | (y)*0x100/10 )

​

static struct {

    int         fan_down_setting;

    int         temp;

    int         fan_up_setting;

} fan_table[] = {

    { 11, T(0,0),  11 },    /* min fan */

    { 11, T(55,0), 11 },

    {  6, T(55,3), 11 },

    {  7, T(56,0), 11 },

    {  8, T(57,0), 8 },

    {  7, T(58,3), 7 },

    {  6, T(58,8), 6 },

    {  5, T(59,2), 5 },

    {  4, T(59,6), 4 },

    {  3, T(59,9), 3 },

    {  2, T(60,1), 2 },

    {  1, 0xfffff, 1 }  /* on fire */

};

​

static void