[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / macintosh / therm_windtunnel.c

/* 
 *   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
 *	temperatur 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/slab.h>
#include <linux/init.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/sections.h>
#include <asm/of_device.h>
#include <asm/macio.h>

#define LOG_TEMP		0			/* continously log temperature */

#define I2C_DRIVERID_G4FAN	0x9001			/* fixme */

static int 			do_probe( struct i2c_adapter *adapter, int addr, int kind);

/* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
static unsigned short		normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
						 0x4c, 0x4d, 0x4e, 0x4f,
						 0x2c, 0x2d, 0x2e, 0x2f,
						 I2C_CLIENT_END };

I2C_CLIENT_INSMOD;

static struct {
	volatile int		running;
	struct completion	completion;
	pid_t			poll_task;
	
	struct semaphore 	lock;
	struct of_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
print_temp( const char *s, int temp )
{
	printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
}

static ssize_t
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
show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf )
{
	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 );
static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );


/************************************************************************/
/*	controller thread						*/
/************************************************************************/

static int
write_reg( struct i2c_client *cl, int reg, int data, int len )
{
	u8 tmp[3];

	if( len < 1 || len > 2 || data < 0 )
		return -EINVAL;

	tmp[0] = reg;
	tmp[1] = (len == 1) ? data : (data >> 8);
	tmp[2] = data;
	len++;
	
	if( i2c_master_send(cl, tmp, len) != len )
		return -ENODEV;
	return 0;
}

static int
read_reg( struct i2c_client *cl, int reg, int len )
{
	u8 buf[2];

	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 )
		return -ENODEV;
	return (len == 2)? ((unsigned int)buf[0] << 8) | buf[1] : buf[0];
}

static void
tune_fan( int fan_setting )
{
	int val = (fan_setting << 3) | 7;

	/* write_reg( x.fan, 0x24, val, 1 ); */
	write_reg( x.fan, 0x25, val, 1 );
	write_reg( x.fan, 0x20, 0, 1 );
	print_temp("CPU-temp: ", x.temp );
	if( x.casetemp )
		print_temp(", Case: ", x.casetemp );
	printk(",  Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting );

	x.fan_level = fan_setting;
}

static void
poll_temp( void )
{
	int temp, i, level, casetemp;

	temp = read_reg( x.thermostat, 0, 2 );

	/* this actually occurs when the computer is loaded */
	if( temp < 0 )
		return;

	casetemp = read_reg(x.fan, 0x0b, 1) << 8;
	casetemp |= (read_reg(x.fan, 0x06, 1) & 0x7) << 5;

	if( LOG_TEMP && x.temp != temp ) {
		print_temp("CPU-temp: ", temp );
		print_temp(", Case: ", casetemp );
		printk(",  Fan: %d\n", 11-x.fan_level );
	}
	x.temp = temp;
	x.casetemp = casetemp;

	level = -1;
	for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ )
		;
	if( i < x.downind )
		level = fan_table[i].fan_down_setting;
	x.downind = i;

	for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ )
		;
	if( x.upind < i )
		level = fan_table[i].fan_up_setting;
	x.upind = i;

	if( level >= 0 )
		tune_fan( level );
}


static void
setup_hardware( void )
{
	int val;

	/* save registers (if we unload the module) */
	x.r0 = read_reg( x.fan, 0x00, 1 );
	x.r1 = read_reg( x.fan, 0x01, 1 );
	x.r20 = read_reg( x.fan, 0x20, 1 );
	x.r23 = read_reg( x.fan, 0x23, 1 );
	x.r25 = read_reg( x.fan, 0x25, 1 );

	/* improve measurement resolution (convergence time 1.5s) */
	if( (val=read_reg(x.thermostat, 1, 1)) >= 0 ) {
		val |= 0x60;
		if( write_reg( x.thermostat, 1, val, 1 ) )
			printk("Failed writing config register\n");
	}
	/* disable interrupts and TAC input */
	write_reg( x.fan, 0x01, 0x01, 1 );
	/* enable filter */
	write_reg( x.fan, 0x23, 0x91, 1 );
	/* remote temp. controls fan */
	write_reg( x.fan, 0x00, 0x95, 1 );

	/* The thermostat (which besides measureing temperature controls
	 * has a THERM output which puts the fan on 100%) is usually
	 * set to kick in at 80 C (chip default). We reduce this a bit
	 * to be on the safe side (OSX doesn't)...
	 */
	if( x.overheat_temp == (80 << 8) ) {
		x.overheat_temp = 65 << 8;
		x.overheat_hyst = 60 << 8;
		write_reg( x.thermostat, 2, x.overheat_hyst, 2 );
		write_reg( x.thermostat, 3, x.overheat_temp, 2 );

		print_temp("Reducing overheating limit to ", x.overheat_temp );
		print_temp(" (Hyst: ", x.overheat_hyst );
		printk(")\n");
	}

	/* set an initial fan setting */
	x.downind = 0xffff;
	x.upind = -1;
	/* tune_fan( fan_up_table[x.upind].fan_setting ); */

	device_create_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
	device_create_file( &x.of_dev->dev, &dev_attr_case_temperature );
}

static void
restore_regs( void )
{
	device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
	device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature );

	write_reg( x.fan, 0x01, x.r1, 1 );
	write_reg( x.fan, 0x20, x.r20, 1 );
	write_reg( x.fan, 0x23, x.r23, 1 );
	write_reg( x.fan, 0x25, x.r25, 1 );
	write_reg( x.fan, 0x00, x.r0, 1 );
}

static int
control_loop( void *dummy )
{
	daemonize("g4fand");

	down( &x.lock );
	setup_hardware();

	while( x.running ) {
		up( &x.lock );

		msleep_interruptible(8000);
		
		down( &x.lock );
		poll_temp();
	}

	restore_regs();
	up( &x.lock );

	complete_and_exit( &x.completion, 0 );
}


/************************************************************************/
/*	i2c probing and setup						*/
/************************************************************************/

static int
do_attach( struct i2c_adapter *adapter )
{
	int ret = 0;

	if( strncmp(adapter->name, "uni-n", 5) )
		return 0;

	if( !x.running ) {
		ret = i2c_probe( adapter, &addr_data, &do_probe );
		if( x.thermostat && x.fan ) {
			x.running = 1;
			init_completion( &x.completion );
			x.poll_task = kernel_thread( control_loop, NULL, SIGCHLD | CLONE_KERNEL );
		}
	}
	return ret;
}

static int
do_detach( struct i2c_client *client )
{
	int err;

	if( (err=i2c_detach_client(client)) )
		printk(KERN_ERR "failed to detach thermostat client\n");
	else {
		if( x.running ) {
			x.running = 0;
			wait_for_completion( &x.completion );
		}
		if( client == x.thermostat )
			x.thermostat = NULL;
		else if( client == x.fan )
			x.fan = NULL;
		else {
			printk(KERN_ERR "g4fan: bad client\n");
		}
		kfree( client );
	}
	return err;
}

static struct i2c_driver g4fan_driver = {  
	.driver = {
		.name	= "therm_windtunnel",
	},
	.id		= I2C_DRIVERID_G4FAN,
	.attach_adapter = do_attach,
	.detach_client	= do_detach,
};

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 );

	strlcpy( cl->name, "ADM1030 fan controller", sizeof(cl->name) );

	if( !i2c_attach_client(cl) )
		x.fan = cl;
 out:
	if( cl != x.fan )
		kfree( cl );
	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;
	
	strlcpy( cl->name, "DS1775 thermostat", sizeof(cl->name) );

	if( !i2c_attach_client(cl) )
		x.thermostat = cl;
out:
	if( cl != x.thermostat )
		kfree( cl );
	return 0;
}

static int
do_probe( struct i2c_adapter *adapter, int addr, int kind )
{
	struct i2c_client *cl;

	if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA
				     | I2C_FUNC_SMBUS_WRITE_BYTE) )
		return 0;

	if( !(cl=kmalloc(sizeof(*cl), GFP_KERNEL)) )
		return -ENOMEM;
	memset( cl, 0, sizeof(struct i2c_client) );

	cl->addr = addr;
	cl->adapter = adapter;
	cl->driver = &g4fan_driver;
	cl->flags = 0;

	if( addr < 0x48 )
		return attach_fan( cl );
	return attach_thermostat( cl );
}


/************************************************************************/
/*	initialization / cleanup					*/
/************************************************************************/

static int
therm_of_probe( struct of_device *dev, const struct of_device_id *match )
{
	return i2c_add_driver( &g4fan_driver );
}

static int
therm_of_remove( struct of_device *dev )
{
	return i2c_del_driver( &g4fan_driver );
}

static struct of_device_id therm_of_match[] = {{
	.name		= "fan",
	.compatible	= "adm1030"
    }, {}
};

static struct of_platform_driver therm_of_driver = {
	.name		= "temperature",
	.match_table	= therm_of_match,
	.probe		= therm_of_probe,
	.remove		= therm_of_remove,
};

struct apple_thermal_info {
	u8		id;			/* implementation ID */
	u8		fan_count;		/* number of fans */
	u8		thermostat_count;	/* number of thermostats */
	u8		unused;
};

static int __init
g4fan_init( void )
{
	const struct apple_thermal_info *info;
	struct device_node *np;

	init_MUTEX( &x.lock );

	if( !(np=of_find_node_by_name(NULL, "power-mgt")) )
		return -ENODEV;
	info = get_property(np, "thermal-info", NULL);
	of_node_put(np);

	if( !info || !machine_is_compatible("PowerMac3,6") )
		return -ENODEV;

	if( info->id != 3 ) {
		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;
	}

	of_register_driver( &therm_of_driver );
	return 0;
}

static void __exit
g4fan_exit( void )
{
	of_unregister_driver( &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");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Creation Date: <2003/03/14 20:54:13 samuel>
	3	* Time-stamp: <2004/03/20 14:20:59 samuel>
	4	*
	5	* <therm_windtunnel.c>
	6	*
	7	* The G4 "windtunnel" has a single fan controlled by an
	8	* ADM1030 fan controller and a DS1775 thermostat.
	9	*
	10	* The fan controller is equipped with a temperature sensor
	11	* which measures the case temperature. The DS1775 sensor
	12	* measures the CPU temperature. This driver tunes the
	13	* behavior of the fan. It is based upon empirical observations
	14	* of the 'AppleFan' driver under Mac OS X.
	15	*
	16	* WARNING: This driver has only been testen on Apple's
	17	* 1.25 MHz Dual G4 (March 03). It is tuned for a CPU
	18	* temperatur around 57 C.
	19	*
	20	* Copyright (C) 2003, 2004 Samuel Rydh (samuel@ibrium.se)
	21	*
	22	* Loosely based upon 'thermostat.c' written by Benjamin Herrenschmidt
	23	*
	24	* This program is free software; you can redistribute it and/or
	25	* modify it under the terms of the GNU General Public License
	26	* as published by the Free Software Foundation
	27	*
	28	*/
	29
1da177e4 LT	30	#include <linux/types.h>
	31	#include <linux/module.h>
	32	#include <linux/errno.h>
	33	#include <linux/kernel.h>
	34	#include <linux/delay.h>
	35	#include <linux/sched.h>
	36	#include <linux/i2c.h>
	37	#include <linux/slab.h>
	38	#include <linux/init.h>
	39	#include <asm/prom.h>
	40	#include <asm/machdep.h>
	41	#include <asm/io.h>
	42	#include <asm/system.h>
	43	#include <asm/sections.h>
	44	#include <asm/of_device.h>
5e655772	45	#include <asm/macio.h>
1da177e4 LT	46
	47	#define LOG_TEMP 0 /* continously log temperature */
	48
	49	#define I2C_DRIVERID_G4FAN 0x9001 /* fixme */
	50
	51	static int do_probe( struct i2c_adapter *adapter, int addr, int kind);
	52
	53	/* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
b3d5496e JD	54	static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
	55	0x4c, 0x4d, 0x4e, 0x4f,
	56	0x2c, 0x2d, 0x2e, 0x2f,
	57	I2C_CLIENT_END };
1da177e4 LT	58
	59	I2C_CLIENT_INSMOD;
	60
	61	static struct {
	62	volatile int running;
	63	struct completion completion;
	64	pid_t poll_task;
	65
	66	struct semaphore lock;
	67	struct of_device *of_dev;
	68
	69	struct i2c_client *thermostat;
	70	struct i2c_client *fan;
	71
	72	int overheat_temp; /* 100% fan at this temp */
	73	int overheat_hyst;
	74	int temp;
	75	int casetemp;
	76	int fan_level; /* active fan_table setting */
	77
	78	int downind;
	79	int upind;
	80
	81	int r0, r1, r20, r23, r25; /* saved register */
	82	} x;
	83
	84	#define T(x,y) (((x)<<8) \| (y)*0x100/10 )
	85
	86	static struct {
	87	int fan_down_setting;
	88	int temp;
	89	int fan_up_setting;
	90	} fan_table[] = {
	91	{ 11, T(0,0), 11 }, /* min fan */
	92	{ 11, T(55,0), 11 },
	93	{ 6, T(55,3), 11 },
	94	{ 7, T(56,0), 11 },
	95	{ 8, T(57,0), 8 },
	96	{ 7, T(58,3), 7 },
	97	{ 6, T(58,8), 6 },
	98	{ 5, T(59,2), 5 },
	99	{ 4, T(59,6), 4 },
	100	{ 3, T(59,9), 3 },
	101	{ 2, T(60,1), 2 },
	102	{ 1, 0xfffff, 1 } /* on fire */
	103	};
	104
	105	static void
	106	print_temp( const char *s, int temp )
	107	{
	108	printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
	109	}
	110
	111	static ssize_t
e404e274	112	show_cpu_temperature( struct device dev, struct device_attribute attr, char *buf )
1da177e4 LT	113	{
	114	return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 );
	115	}
	116
	117	static ssize_t
e404e274	118	show_case_temperature( struct device dev, struct device_attribute attr, char *buf )
1da177e4 LT	119	{
	120	return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 );
	121	}
	122
	123	static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL );
	124	static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );
	125
	126
	127
	128	/************************************************************************/
	129	/* controller thread */
	130	/************************************************************************/
	131
	132	static int
	133	write_reg( struct i2c_client *cl, int reg, int data, int len )
	134	{
	135	u8 tmp[3];
	136
	137	if( len < 1 \|\| len > 2 \|\| data < 0 )
	138	return -EINVAL;
	139
	140	tmp[0] = reg;
	141	tmp[1] = (len == 1) ? data : (data >> 8);
	142	tmp[2] = data;
	143	len++;
	144
	145	if( i2c_master_send(cl, tmp, len) != len )
	146	return -ENODEV;
	147	return 0;
	148	}
	149
	150	static int
	151	read_reg( struct i2c_client *cl, int reg, int len )
	152	{
	153	u8 buf[2];
	154
	155	if( len != 1 && len != 2 )
	156	return -EINVAL;
	157	buf[0] = reg;
	158	if( i2c_master_send(cl, buf, 1) != 1 )
	159	return -ENODEV;
	160	if( i2c_master_recv(cl, buf, len) != len )
	161	return -ENODEV;
	162	return (len == 2)? ((unsigned int)buf[0] << 8) \| buf[1] : buf[0];
	163	}
	164
	165	static void
	166	tune_fan( int fan_setting )
	167	{
	168	int val = (fan_setting << 3) \| 7;
	169
	170	/* write_reg( x.fan, 0x24, val, 1 ); */
	171	write_reg( x.fan, 0x25, val, 1 );
	172	write_reg( x.fan, 0x20, 0, 1 );
	173	print_temp("CPU-temp: ", x.temp );
	174	if( x.casetemp )
	175	print_temp(", Case: ", x.casetemp );
	176	printk(", Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting );
	177
	178	x.fan_level = fan_setting;
	179	}
	180
	181	static void
	182	poll_temp( void )
183	{
184	int temp, i, level, casetemp;
185
186	temp = read_reg( x.thermostat, 0, 2 );
187
188	/* this actually occurs when the computer is loaded */
189	if( temp < 0 )
190	return;
191
192	casetemp = read_reg(x.fan, 0x0b, 1) << 8;
193	casetemp \|= (read_reg(x.fan, 0x06, 1) & 0x7) << 5;
194
195	if( LOG_TEMP && x.temp != temp ) {
196	print_temp("CPU-temp: ", temp );
197	print_temp(", Case: ", casetemp );
198	printk(", Fan: %d\n", 11-x.fan_level );
199	}
200	x.temp = temp;
201	x.casetemp = casetemp;
202
203	level = -1;
204	for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ )
205	;
206	if( i < x.downind )
207	level = fan_table[i].fan_down_setting;
208	x.downind = i;
209
210	for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ )
211	;
212	if( x.upind < i )
213	level = fan_table[i].fan_up_setting;
214	x.upind = i;
215
216	if( level >= 0 )
217	tune_fan( level );
218	}
219
220
221	static void
222	setup_hardware( void )
223	{
224	int val;
225
226	/* save registers (if we unload the module) */
227	x.r0 = read_reg( x.fan, 0x00, 1 );
228	x.r1 = read_reg( x.fan, 0x01, 1 );
229	x.r20 = read_reg( x.fan, 0x20, 1 );
230	x.r23 = read_reg( x.fan, 0x23, 1 );
231	x.r25 = read_reg( x.fan, 0x25, 1 );
232
233	/* improve measurement resolution (convergence time 1.5s) */
234	if( (val=read_reg(x.thermostat, 1, 1)) >= 0 ) {
235	val \|= 0x60;
236	if( write_reg( x.thermostat, 1, val, 1 ) )
237	printk("Failed writing config register\n");
238	}
239	/* disable interrupts and TAC input */
240	write_reg( x.fan, 0x01, 0x01, 1 );
241	/* enable filter */
242	write_reg( x.fan, 0x23, 0x91, 1 );
243	/* remote temp. controls fan */
244	write_reg( x.fan, 0x00, 0x95, 1 );
245
246	/* The thermostat (which besides measureing temperature controls
247	* has a THERM output which puts the fan on 100%) is usually
248	* set to kick in at 80 C (chip default). We reduce this a bit
249	* to be on the safe side (OSX doesn't)...
250	*/
251	if( x.overheat_temp == (80 << 8) ) {
252	x.overheat_temp = 65 << 8;
253	x.overheat_hyst = 60 << 8;
254	write_reg( x.thermostat, 2, x.overheat_hyst, 2 );
255	write_reg( x.thermostat, 3, x.overheat_temp, 2 );
256
257	print_temp("Reducing overheating limit to ", x.overheat_temp );
258	print_temp(" (Hyst: ", x.overheat_hyst );
259	printk(")\n");
260	}
261
262	/* set an initial fan setting */
263	x.downind = 0xffff;
264	x.upind = -1;
265	/* tune_fan( fan_up_table[x.upind].fan_setting ); */
266
267	device_create_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
268	device_create_file( &x.of_dev->dev, &dev_attr_case_temperature );
269	}
270
271	static void
272	restore_regs( void )
273	{
274	device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
275	device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature );
276
277	write_reg( x.fan, 0x01, x.r1, 1 );
278	write_reg( x.fan, 0x20, x.r20, 1 );
279	write_reg( x.fan, 0x23, x.r23, 1 );
280	write_reg( x.fan, 0x25, x.r25, 1 );
281	write_reg( x.fan, 0x00, x.r0, 1 );
282	}
283
284	static int
285	control_loop( void *dummy )
286	{
287	daemonize("g4fand");
288
289	down( &x.lock );
290	setup_hardware();
291
292	while( x.running ) {
293	up( &x.lock );
294
295	msleep_interruptible(8000);
296
297	down( &x.lock );
298	poll_temp();
299	}
300
301	restore_regs();
302	up( &x.lock );
303
304	complete_and_exit( &x.completion, 0 );
305	}
306
307
308	/************************************************************************/
309	/* i2c probing and setup */
310	/************************************************************************/
311
312	static int
313	do_attach( struct i2c_adapter *adapter )
314	{
315	int ret = 0;
316
317	if( strncmp(adapter->name, "uni-n", 5) )
318	return 0;
319
320	if( !x.running ) {
321	ret = i2c_probe( adapter, &addr_data, &do_probe );
322	if( x.thermostat && x.fan ) {
323	x.running = 1;
324	init_completion( &x.completion );
325	x.poll_task = kernel_thread( control_loop, NULL, SIGCHLD \| CLONE_KERNEL );
326	}
327	}
328	return ret;
329	}
330
331	static int
332	do_detach( struct i2c_client *client )
333	{
334	int err;
335
336	if( (err=i2c_detach_client(client)) )
337	printk(KERN_ERR "failed to detach thermostat client\n");
338	else {
339	if( x.running ) {
340	x.running = 0;
341	wait_for_completion( &x.completion );
342	}
343	if( client == x.thermostat )
344	x.thermostat = NULL;
345	else if( client == x.fan )
346	x.fan = NULL;
347	else {
348	printk(KERN_ERR "g4fan: bad client\n");
349	}
350	kfree( client );
351	}
352	return err;
353	}
354
355	static struct i2c_driver g4fan_driver = {
a33ca232	356	.driver = {
a33ca232 LR	357	.name = "therm_windtunnel",
a33ca232 LR	358	},
1da177e4	359	.id = I2C_DRIVERID_G4FAN,
1da177e4 LT	360	.attach_adapter = do_attach,
	361	.detach_client = do_detach,
	362	};
	363
	364	static int
	365	attach_fan( struct i2c_client *cl )
	366	{
	367	if( x.fan )
	368	goto out;
	369
	370	/* check that this is an ADM1030 */
	371	if( read_reg(cl, 0x3d, 1) != 0x30 \|\| read_reg(cl, 0x3e, 1) != 0x41 )
	372	goto out;
	373	printk("ADM1030 fan controller [@%02x]\n", cl->addr );
	374
	375	strlcpy( cl->name, "ADM1030 fan controller", sizeof(cl->name) );
	376
	377	if( !i2c_attach_client(cl) )
	378	x.fan = cl;
	379	out:
	380	if( cl != x.fan )
	381	kfree( cl );
	382	return 0;
	383	}
	384
	385	static int
	386	attach_thermostat( struct i2c_client *cl )
	387	{
	388	int hyst_temp, os_temp, temp;
	389
	390	if( x.thermostat )
	391	goto out;
	392
	393	if( (temp=read_reg(cl, 0, 2)) < 0 )
	394	goto out;
	395
	396	/* temperature sanity check */
	397	if( temp < 0x1600 \|\| temp > 0x3c00 )
	398	goto out;
	399	hyst_temp = read_reg(cl, 2, 2);
	400	os_temp = read_reg(cl, 3, 2);
	401	if( hyst_temp < 0 \|\| os_temp < 0 )
	402	goto out;
	403
	404	printk("DS1775 digital thermometer [@%02x]\n", cl->addr );
	405	print_temp("Temp: ", temp );
	406	print_temp(" Hyst: ", hyst_temp );
	407	print_temp(" OS: ", os_temp );
	408	printk("\n");
	409
	410	x.temp = temp;
	411	x.overheat_temp = os_temp;
	412	x.overheat_hyst = hyst_temp;
	413
	414	strlcpy( cl->name, "DS1775 thermostat", sizeof(cl->name) );
	415
	416	if( !i2c_attach_client(cl) )
	417	x.thermostat = cl;
	418	out:
	419	if( cl != x.thermostat )
	420	kfree( cl );
	421	return 0;
	422	}
	423
424	static int
425	do_probe( struct i2c_adapter *adapter, int addr, int kind )
426	{
427	struct i2c_client *cl;
428
429	if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA
430	\| I2C_FUNC_SMBUS_WRITE_BYTE) )
431	return 0;
432
433	if( !(cl=kmalloc(sizeof(*cl), GFP_KERNEL)) )
434	return -ENOMEM;
435	memset( cl, 0, sizeof(struct i2c_client) );
436
437	cl->addr = addr;
438	cl->adapter = adapter;
439	cl->driver = &g4fan_driver;
440	cl->flags = 0;
441
442	if( addr < 0x48 )
443	return attach_fan( cl );
444	return attach_thermostat( cl );
445	}
446
447
448	/************************************************************************/
449	/* initialization / cleanup */
450	/************************************************************************/
451
452	static int
5e655772	453	therm_of_probe( struct of_device dev, const struct of_device_id match )
1da177e4 LT	454	{
	455	return i2c_add_driver( &g4fan_driver );
	456	}
	457
	458	static int
	459	therm_of_remove( struct of_device *dev )
	460	{
	461	return i2c_del_driver( &g4fan_driver );
	462	}
	463
5e655772	464	static struct of_device_id therm_of_match[] = {{
1da177e4	465	.name = "fan",
1da177e4 LT	466	.compatible = "adm1030"
	467	}, {}
	468	};
	469
	470	static struct of_platform_driver therm_of_driver = {
	471	.name = "temperature",
	472	.match_table = therm_of_match,
	473	.probe = therm_of_probe,
	474	.remove = therm_of_remove,
	475	};
	476
	477	struct apple_thermal_info {
	478	u8 id; /* implementation ID */
	479	u8 fan_count; /* number of fans */
	480	u8 thermostat_count; /* number of thermostats */
	481	u8 unused;
	482	};
	483
	484	static int __init
	485	g4fan_init( void )
	486	{
018a3d1d	487	const struct apple_thermal_info *info;
1da177e4 LT	488	struct device_node *np;
	489
	490	init_MUTEX( &x.lock );
	491
	492	if( !(np=of_find_node_by_name(NULL, "power-mgt")) )
	493	return -ENODEV;
018a3d1d	494	info = get_property(np, "thermal-info", NULL);
1da177e4 LT	495	of_node_put(np);
	496
	497	if( !info \|\| !machine_is_compatible("PowerMac3,6") )
	498	return -ENODEV;
	499
	500	if( info->id != 3 ) {
	501	printk(KERN_ERR "therm_windtunnel: unsupported thermal design %d\n", info->id );
	502	return -ENODEV;
	503	}
	504	if( !(np=of_find_node_by_name(NULL, "fan")) )
	505	return -ENODEV;
0365ba7f	506	x.of_dev = of_platform_device_create(np, "temperature", NULL);
1da177e4 LT	507	of_node_put( np );
	508
	509	if( !x.of_dev ) {
	510	printk(KERN_ERR "Can't register fan controller!\n");
	511	return -ENODEV;
	512	}
	513
	514	of_register_driver( &therm_of_driver );
	515	return 0;
	516	}
	517
	518	static void __exit
	519	g4fan_exit( void )
	520	{
	521	of_unregister_driver( &therm_of_driver );
	522
	523	if( x.of_dev )
	524	of_device_unregister( x.of_dev );
	525	}
	526
	527	module_init(g4fan_init);
	528	module_exit(g4fan_exit);
	529
	530	MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>");
	531	MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller");
	532	MODULE_LICENSE("GPL");