forked from mirrors/linux
		
	 3e7bed5271
			
		
	
	
		3e7bed5271
		
	
	
	
	
		
			
			As we now have deferred probing, we can use a custom mechanism and finally get rid of the legacy interface from the i2c core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au>
		
			
				
	
	
		
			550 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			550 lines
		
	
	
	
		
			12 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* 
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|  *   Creation Date: <2003/03/14 20:54:13 samuel>
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|  *   Time-stamp: <2004/03/20 14:20:59 samuel>
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|  *   
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|  *	<therm_windtunnel.c>
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|  *	
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|  *	The G4 "windtunnel" has a single fan controlled by an
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|  *	ADM1030 fan controller and a DS1775 thermostat.
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|  *
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|  *	The fan controller is equipped with a temperature sensor
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|  *	which measures the case temperature. The DS1775 sensor
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|  *	measures the CPU temperature. This driver tunes the
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|  *	behavior of the fan. It is based upon empirical observations
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|  *	of the 'AppleFan' driver under Mac OS X.
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|  *
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|  *	WARNING: This driver has only been testen on Apple's
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|  *	1.25 MHz Dual G4 (March 03). It is tuned for a CPU
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|  *	temperature around 57 C.
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|  *
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|  *   Copyright (C) 2003, 2004 Samuel Rydh (samuel@ibrium.se)
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|  *
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|  *   Loosely based upon 'thermostat.c' written by Benjamin Herrenschmidt
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|  *   
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|  *   This program is free software; you can redistribute it and/or
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|  *   modify it under the terms of the GNU General Public License
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|  *   as published by the Free Software Foundation
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|  *   
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|  */
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| 
 | |
| #include <linux/types.h>
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| #include <linux/module.h>
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| #include <linux/errno.h>
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| #include <linux/kernel.h>
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| #include <linux/delay.h>
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| #include <linux/sched.h>
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| #include <linux/i2c.h>
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| #include <linux/init.h>
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| #include <linux/kthread.h>
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| #include <linux/of_platform.h>
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| 
 | |
| #include <asm/prom.h>
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| #include <asm/machdep.h>
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| #include <asm/io.h>
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| #include <asm/sections.h>
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| #include <asm/macio.h>
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| 
 | |
| #define LOG_TEMP		0			/* continuously log temperature */
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| 
 | |
| static struct {
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| 	volatile int		running;
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| 	struct task_struct	*poll_task;
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| 	
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| 	struct mutex	 	lock;
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| 	struct platform_device	*of_dev;
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| 	
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| 	struct i2c_client	*thermostat;
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| 	struct i2c_client	*fan;
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| 
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| 	int			overheat_temp;		/* 100% fan at this temp */
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| 	int			overheat_hyst;
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| 	int			temp;
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| 	int			casetemp;
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| 	int			fan_level;		/* active fan_table setting */
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| 
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| 	int			downind;
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| 	int			upind;
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| 
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| 	int			r0, r1, r20, r23, r25;	/* saved register */
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| } x;
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| 
 | |
| #define T(x,y)			(((x)<<8) | (y)*0x100/10 )
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| 
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| static struct {
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| 	int			fan_down_setting;
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| 	int			temp;
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| 	int			fan_up_setting;
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| } fan_table[] = {
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| 	{ 11, T(0,0),  11 },	/* min fan */
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| 	{ 11, T(55,0), 11 },
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| 	{  6, T(55,3), 11 },
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| 	{  7, T(56,0), 11 },
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| 	{  8, T(57,0), 8 },
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| 	{  7, T(58,3), 7 },
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| 	{  6, T(58,8), 6 },
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| 	{  5, T(59,2), 5 },
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| 	{  4, T(59,6), 4 },
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| 	{  3, T(59,9), 3 },
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| 	{  2, T(60,1), 2 },
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| 	{  1, 0xfffff, 1 }	/* on fire */
 | |
| };
 | |
| 
 | |
| static void
 | |
| print_temp( const char *s, int temp )
 | |
| {
 | |
| 	printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
 | |
| }
 | |
| 
 | |
| static ssize_t
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| show_cpu_temperature( struct device *dev, struct device_attribute *attr, char *buf )
 | |
| {
 | |
| 	return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 );
 | |
| }
 | |
| 
 | |
| static ssize_t
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| show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf )
 | |
| {
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| 	return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 );
 | |
| }
 | |
| 
 | |
| static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL );
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| static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );
 | |
| 
 | |
| 
 | |
| 
 | |
| /************************************************************************/
 | |
| /*	controller thread						*/
 | |
| /************************************************************************/
 | |
| 
 | |
| static int
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| write_reg( struct i2c_client *cl, int reg, int data, int len )
 | |
| {
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| 	u8 tmp[3];
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| 
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| 	if( len < 1 || len > 2 || data < 0 )
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| 		return -EINVAL;
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| 
 | |
| 	tmp[0] = reg;
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| 	tmp[1] = (len == 1) ? data : (data >> 8);
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| 	tmp[2] = data;
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| 	len++;
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| 	
 | |
| 	if( i2c_master_send(cl, tmp, len) != len )
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| 		return -ENODEV;
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int
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| read_reg( struct i2c_client *cl, int reg, int len )
 | |
| {
 | |
| 	u8 buf[2];
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| 
 | |
| 	if( len != 1 && len != 2 )
 | |
| 		return -EINVAL;
 | |
| 	buf[0] = reg;
 | |
| 	if( i2c_master_send(cl, buf, 1) != 1 )
 | |
| 		return -ENODEV;
 | |
| 	if( i2c_master_recv(cl, buf, len) != len )
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| 		return -ENODEV;
 | |
| 	return (len == 2)? ((unsigned int)buf[0] << 8) | buf[1] : buf[0];
 | |
| }
 | |
| 
 | |
| static void
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| tune_fan( int fan_setting )
 | |
| {
 | |
| 	int val = (fan_setting << 3) | 7;
 | |
| 
 | |
| 	/* write_reg( x.fan, 0x24, val, 1 ); */
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| 	write_reg( x.fan, 0x25, val, 1 );
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| 	write_reg( x.fan, 0x20, 0, 1 );
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| 	print_temp("CPU-temp: ", x.temp );
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| 	if( x.casetemp )
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| 		print_temp(", Case: ", x.casetemp );
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| 	printk(",  Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting );
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| 
 | |
| 	x.fan_level = fan_setting;
 | |
| }
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| 
 | |
| static void
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| poll_temp( void )
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| {
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| 	int temp, i, level, casetemp;
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| 
 | |
| 	temp = read_reg( x.thermostat, 0, 2 );
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| 
 | |
| 	/* this actually occurs when the computer is loaded */
 | |
| 	if( temp < 0 )
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| 		return;
 | |
| 
 | |
| 	casetemp = read_reg(x.fan, 0x0b, 1) << 8;
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| 	casetemp |= (read_reg(x.fan, 0x06, 1) & 0x7) << 5;
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| 
 | |
| 	if( LOG_TEMP && x.temp != temp ) {
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| 		print_temp("CPU-temp: ", temp );
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| 		print_temp(", Case: ", casetemp );
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| 		printk(",  Fan: %d\n", 11-x.fan_level );
 | |
| 	}
 | |
| 	x.temp = temp;
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| 	x.casetemp = casetemp;
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| 
 | |
| 	level = -1;
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| 	for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ )
 | |
| 		;
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| 	if( i < x.downind )
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| 		level = fan_table[i].fan_down_setting;
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| 	x.downind = i;
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| 
 | |
| 	for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ )
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| 		;
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| 	if( x.upind < i )
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| 		level = fan_table[i].fan_up_setting;
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| 	x.upind = i;
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| 
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| 	if( level >= 0 )
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| 		tune_fan( level );
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| }
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| 
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| 
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| static void
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| setup_hardware( void )
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| {
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| 	int val;
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| 	int err;
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| 
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| 	/* save registers (if we unload the module) */
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| 	x.r0 = read_reg( x.fan, 0x00, 1 );
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| 	x.r1 = read_reg( x.fan, 0x01, 1 );
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| 	x.r20 = read_reg( x.fan, 0x20, 1 );
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| 	x.r23 = read_reg( x.fan, 0x23, 1 );
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| 	x.r25 = read_reg( x.fan, 0x25, 1 );
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| 
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| 	/* improve measurement resolution (convergence time 1.5s) */
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| 	if( (val=read_reg(x.thermostat, 1, 1)) >= 0 ) {
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| 		val |= 0x60;
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| 		if( write_reg( x.thermostat, 1, val, 1 ) )
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| 			printk("Failed writing config register\n");
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| 	}
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| 	/* disable interrupts and TAC input */
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| 	write_reg( x.fan, 0x01, 0x01, 1 );
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| 	/* enable filter */
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| 	write_reg( x.fan, 0x23, 0x91, 1 );
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| 	/* remote temp. controls fan */
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| 	write_reg( x.fan, 0x00, 0x95, 1 );
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| 
 | |
| 	/* The thermostat (which besides measureing temperature controls
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| 	 * has a THERM output which puts the fan on 100%) is usually
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| 	 * set to kick in at 80 C (chip default). We reduce this a bit
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| 	 * to be on the safe side (OSX doesn't)...
 | |
| 	 */
 | |
| 	if( x.overheat_temp == (80 << 8) ) {
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| 		x.overheat_temp = 75 << 8;
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| 		x.overheat_hyst = 70 << 8;
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| 		write_reg( x.thermostat, 2, x.overheat_hyst, 2 );
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| 		write_reg( x.thermostat, 3, x.overheat_temp, 2 );
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| 
 | |
| 		print_temp("Reducing overheating limit to ", x.overheat_temp );
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| 		print_temp(" (Hyst: ", x.overheat_hyst );
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| 		printk(")\n");
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| 	}
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| 
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| 	/* set an initial fan setting */
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| 	x.downind = 0xffff;
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| 	x.upind = -1;
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| 	/* tune_fan( fan_up_table[x.upind].fan_setting ); */
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| 
 | |
| 	err = device_create_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
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| 	err |= device_create_file( &x.of_dev->dev, &dev_attr_case_temperature );
 | |
| 	if (err)
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| 		printk(KERN_WARNING
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| 			"Failed to create temperature attribute file(s).\n");
 | |
| }
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| 
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| static void
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| restore_regs( void )
 | |
| {
 | |
| 	device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
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| 	device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature );
 | |
| 
 | |
| 	write_reg( x.fan, 0x01, x.r1, 1 );
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| 	write_reg( x.fan, 0x20, x.r20, 1 );
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| 	write_reg( x.fan, 0x23, x.r23, 1 );
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| 	write_reg( x.fan, 0x25, x.r25, 1 );
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| 	write_reg( x.fan, 0x00, x.r0, 1 );
 | |
| }
 | |
| 
 | |
| static int control_loop(void *dummy)
 | |
| {
 | |
| 	mutex_lock(&x.lock);
 | |
| 	setup_hardware();
 | |
| 	mutex_unlock(&x.lock);
 | |
| 
 | |
| 	for (;;) {
 | |
| 		msleep_interruptible(8000);
 | |
| 		if (kthread_should_stop())
 | |
| 			break;
 | |
| 
 | |
| 		mutex_lock(&x.lock);
 | |
| 		poll_temp();
 | |
| 		mutex_unlock(&x.lock);
 | |
| 	}
 | |
| 
 | |
| 	mutex_lock(&x.lock);
 | |
| 	restore_regs();
 | |
| 	mutex_unlock(&x.lock);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| 
 | |
| /************************************************************************/
 | |
| /*	i2c probing and setup						*/
 | |
| /************************************************************************/
 | |
| 
 | |
| static int
 | |
| do_attach( struct i2c_adapter *adapter )
 | |
| {
 | |
| 	/* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
 | |
| 	static const unsigned short scan_ds1775[] = {
 | |
| 		0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
 | |
| 		I2C_CLIENT_END
 | |
| 	};
 | |
| 	static const unsigned short scan_adm1030[] = {
 | |
| 		0x2c, 0x2d, 0x2e, 0x2f,
 | |
| 		I2C_CLIENT_END
 | |
| 	};
 | |
| 
 | |
| 	if( strncmp(adapter->name, "uni-n", 5) )
 | |
| 		return 0;
 | |
| 
 | |
| 	if( !x.running ) {
 | |
| 		struct i2c_board_info info;
 | |
| 
 | |
| 		memset(&info, 0, sizeof(struct i2c_board_info));
 | |
| 		strlcpy(info.type, "therm_ds1775", I2C_NAME_SIZE);
 | |
| 		i2c_new_probed_device(adapter, &info, scan_ds1775, NULL);
 | |
| 
 | |
| 		strlcpy(info.type, "therm_adm1030", I2C_NAME_SIZE);
 | |
| 		i2c_new_probed_device(adapter, &info, scan_adm1030, NULL);
 | |
| 
 | |
| 		if( x.thermostat && x.fan ) {
 | |
| 			x.running = 1;
 | |
| 			x.poll_task = kthread_run(control_loop, NULL, "g4fand");
 | |
| 		}
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int
 | |
| do_remove(struct i2c_client *client)
 | |
| {
 | |
| 	if (x.running) {
 | |
| 		x.running = 0;
 | |
| 		kthread_stop(x.poll_task);
 | |
| 		x.poll_task = NULL;
 | |
| 	}
 | |
| 	if (client == x.thermostat)
 | |
| 		x.thermostat = NULL;
 | |
| 	else if (client == x.fan)
 | |
| 		x.fan = NULL;
 | |
| 	else
 | |
| 		printk(KERN_ERR "g4fan: bad client\n");
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int
 | |
| attach_fan( struct i2c_client *cl )
 | |
| {
 | |
| 	if( x.fan )
 | |
| 		goto out;
 | |
| 
 | |
| 	/* check that this is an ADM1030 */
 | |
| 	if( read_reg(cl, 0x3d, 1) != 0x30 || read_reg(cl, 0x3e, 1) != 0x41 )
 | |
| 		goto out;
 | |
| 	printk("ADM1030 fan controller [@%02x]\n", cl->addr );
 | |
| 
 | |
| 	x.fan = cl;
 | |
|  out:
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int
 | |
| attach_thermostat( struct i2c_client *cl ) 
 | |
| {
 | |
| 	int hyst_temp, os_temp, temp;
 | |
| 
 | |
| 	if( x.thermostat )
 | |
| 		goto out;
 | |
| 
 | |
| 	if( (temp=read_reg(cl, 0, 2)) < 0 )
 | |
| 		goto out;
 | |
| 	
 | |
| 	/* temperature sanity check */
 | |
| 	if( temp < 0x1600 || temp > 0x3c00 )
 | |
| 		goto out;
 | |
| 	hyst_temp = read_reg(cl, 2, 2);
 | |
| 	os_temp = read_reg(cl, 3, 2);
 | |
| 	if( hyst_temp < 0 || os_temp < 0 )
 | |
| 		goto out;
 | |
| 
 | |
| 	printk("DS1775 digital thermometer [@%02x]\n", cl->addr );
 | |
| 	print_temp("Temp: ", temp );
 | |
| 	print_temp("  Hyst: ", hyst_temp );
 | |
| 	print_temp("  OS: ", os_temp );
 | |
| 	printk("\n");
 | |
| 
 | |
| 	x.temp = temp;
 | |
| 	x.overheat_temp = os_temp;
 | |
| 	x.overheat_hyst = hyst_temp;
 | |
| 	x.thermostat = cl;
 | |
| out:
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| enum chip { ds1775, adm1030 };
 | |
| 
 | |
| static const struct i2c_device_id therm_windtunnel_id[] = {
 | |
| 	{ "therm_ds1775", ds1775 },
 | |
| 	{ "therm_adm1030", adm1030 },
 | |
| 	{ }
 | |
| };
 | |
| MODULE_DEVICE_TABLE(i2c, therm_windtunnel_id);
 | |
| 
 | |
| static int
 | |
| do_probe(struct i2c_client *cl, const struct i2c_device_id *id)
 | |
| {
 | |
| 	struct i2c_adapter *adapter = cl->adapter;
 | |
| 
 | |
| 	if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA
 | |
| 				     | I2C_FUNC_SMBUS_WRITE_BYTE) )
 | |
| 		return 0;
 | |
| 
 | |
| 	switch (id->driver_data) {
 | |
| 	case adm1030:
 | |
| 		return attach_fan( cl );
 | |
| 	case ds1775:
 | |
| 		return attach_thermostat(cl);
 | |
| 	}
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static struct i2c_driver g4fan_driver = {
 | |
| 	.driver = {
 | |
| 		.name	= "therm_windtunnel",
 | |
| 	},
 | |
| 	.probe		= do_probe,
 | |
| 	.remove		= do_remove,
 | |
| 	.id_table	= therm_windtunnel_id,
 | |
| };
 | |
| 
 | |
| 
 | |
| /************************************************************************/
 | |
| /*	initialization / cleanup					*/
 | |
| /************************************************************************/
 | |
| 
 | |
| static int therm_of_probe(struct platform_device *dev)
 | |
| {
 | |
| 	struct i2c_adapter *adap;
 | |
| 	int ret, i = 0;
 | |
| 
 | |
| 	adap = i2c_get_adapter(0);
 | |
| 	if (!adap)
 | |
| 		return -EPROBE_DEFER;
 | |
| 
 | |
| 	ret = i2c_add_driver(&g4fan_driver);
 | |
| 	if (ret) {
 | |
| 		i2c_put_adapter(adap);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	/* We assume Macs have consecutive I2C bus numbers starting at 0 */
 | |
| 	while (adap) {
 | |
| 		do_attach(adap);
 | |
| 		if (x.running)
 | |
| 			return 0;
 | |
| 		i2c_put_adapter(adap);
 | |
| 		adap = i2c_get_adapter(++i);
 | |
| 	}
 | |
| 
 | |
| 	return -ENODEV;
 | |
| }
 | |
| 
 | |
| static int
 | |
| therm_of_remove( struct platform_device *dev )
 | |
| {
 | |
| 	i2c_del_driver( &g4fan_driver );
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static const struct of_device_id therm_of_match[] = {{
 | |
| 	.name		= "fan",
 | |
| 	.compatible	= "adm1030"
 | |
|     }, {}
 | |
| };
 | |
| MODULE_DEVICE_TABLE(of, therm_of_match);
 | |
| 
 | |
| static struct platform_driver therm_of_driver = {
 | |
| 	.driver = {
 | |
| 		.name = "temperature",
 | |
| 		.of_match_table = therm_of_match,
 | |
| 	},
 | |
| 	.probe		= therm_of_probe,
 | |
| 	.remove		= therm_of_remove,
 | |
| };
 | |
| 
 | |
| struct apple_thermal_info {
 | |
| 	u8		id;			/* implementation ID */
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| 	u8		fan_count;		/* number of fans */
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| 	u8		thermostat_count;	/* number of thermostats */
 | |
| 	u8		unused;
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| };
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| 
 | |
| static int __init
 | |
| g4fan_init( void )
 | |
| {
 | |
| 	const struct apple_thermal_info *info;
 | |
| 	struct device_node *np;
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| 
 | |
| 	mutex_init(&x.lock);
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| 
 | |
| 	if( !(np=of_find_node_by_name(NULL, "power-mgt")) )
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| 		return -ENODEV;
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| 	info = of_get_property(np, "thermal-info", NULL);
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| 	of_node_put(np);
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| 
 | |
| 	if( !info || !of_machine_is_compatible("PowerMac3,6") )
 | |
| 		return -ENODEV;
 | |
| 
 | |
| 	if( info->id != 3 ) {
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| 		printk(KERN_ERR "therm_windtunnel: unsupported thermal design %d\n", info->id );
 | |
| 		return -ENODEV;
 | |
| 	}
 | |
| 	if( !(np=of_find_node_by_name(NULL, "fan")) )
 | |
| 		return -ENODEV;
 | |
| 	x.of_dev = of_platform_device_create(np, "temperature", NULL);
 | |
| 	of_node_put( np );
 | |
| 
 | |
| 	if( !x.of_dev ) {
 | |
| 		printk(KERN_ERR "Can't register fan controller!\n");
 | |
| 		return -ENODEV;
 | |
| 	}
 | |
| 
 | |
| 	platform_driver_register( &therm_of_driver );
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static void __exit
 | |
| g4fan_exit( void )
 | |
| {
 | |
| 	platform_driver_unregister( &therm_of_driver );
 | |
| 
 | |
| 	if( x.of_dev )
 | |
| 		of_device_unregister( x.of_dev );
 | |
| }
 | |
| 
 | |
| module_init(g4fan_init);
 | |
| module_exit(g4fan_exit);
 | |
| 
 | |
| MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>");
 | |
| MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller");
 | |
| MODULE_LICENSE("GPL");
 |