2 * Creation Date: <2003/03/14 20:54:13 samuel>
3 * Time-stamp: <2004/03/20 14:20:59 samuel>
7 * The G4 "windtunnel" has a single fan controlled by an
8 * ADM1030 fan controller and a DS1775 thermostat.
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.
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.
20 * Copyright (C) 2003, 2004 Samuel Rydh (samuel@ibrium.se)
22 * Loosely based upon 'thermostat.c' written by Benjamin Herrenschmidt
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
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 <linux/kthread.h>
40 #include <linux/of_platform.h>
43 #include <asm/machdep.h>
45 #include <asm/system.h>
46 #include <asm/sections.h>
47 #include <asm/macio.h>
49 #define LOG_TEMP 0 /* continously log temperature */
53 struct task_struct *poll_task;
56 struct of_device *of_dev;
58 struct i2c_client *thermostat;
59 struct i2c_client *fan;
61 int overheat_temp; /* 100% fan at this temp */
65 int fan_level; /* active fan_table setting */
70 int r0, r1, r20, r23, r25; /* saved register */
73 #define T(x,y) (((x)<<8) | (y)*0x100/10 )
80 { 11, T(0,0), 11 }, /* min fan */
91 { 1, 0xfffff, 1 } /* on fire */
95 print_temp( const char *s, int temp )
97 printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
101 show_cpu_temperature( struct device *dev, struct device_attribute *attr, char *buf )
103 return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 );
107 show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf )
109 return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 );
112 static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL );
113 static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );
117 /************************************************************************/
118 /* controller thread */
119 /************************************************************************/
122 write_reg( struct i2c_client *cl, int reg, int data, int len )
126 if( len < 1 || len > 2 || data < 0 )
130 tmp[1] = (len == 1) ? data : (data >> 8);
134 if( i2c_master_send(cl, tmp, len) != len )
140 read_reg( struct i2c_client *cl, int reg, int len )
144 if( len != 1 && len != 2 )
147 if( i2c_master_send(cl, buf, 1) != 1 )
149 if( i2c_master_recv(cl, buf, len) != len )
151 return (len == 2)? ((unsigned int)buf[0] << 8) | buf[1] : buf[0];
155 tune_fan( int fan_setting )
157 int val = (fan_setting << 3) | 7;
159 /* write_reg( x.fan, 0x24, val, 1 ); */
160 write_reg( x.fan, 0x25, val, 1 );
161 write_reg( x.fan, 0x20, 0, 1 );
162 print_temp("CPU-temp: ", x.temp );
164 print_temp(", Case: ", x.casetemp );
165 printk(", Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting );
167 x.fan_level = fan_setting;
173 int temp, i, level, casetemp;
175 temp = read_reg( x.thermostat, 0, 2 );
177 /* this actually occurs when the computer is loaded */
181 casetemp = read_reg(x.fan, 0x0b, 1) << 8;
182 casetemp |= (read_reg(x.fan, 0x06, 1) & 0x7) << 5;
184 if( LOG_TEMP && x.temp != temp ) {
185 print_temp("CPU-temp: ", temp );
186 print_temp(", Case: ", casetemp );
187 printk(", Fan: %d\n", 11-x.fan_level );
190 x.casetemp = casetemp;
193 for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ )
196 level = fan_table[i].fan_down_setting;
199 for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ )
202 level = fan_table[i].fan_up_setting;
211 setup_hardware( void )
216 /* save registers (if we unload the module) */
217 x.r0 = read_reg( x.fan, 0x00, 1 );
218 x.r1 = read_reg( x.fan, 0x01, 1 );
219 x.r20 = read_reg( x.fan, 0x20, 1 );
220 x.r23 = read_reg( x.fan, 0x23, 1 );
221 x.r25 = read_reg( x.fan, 0x25, 1 );
223 /* improve measurement resolution (convergence time 1.5s) */
224 if( (val=read_reg(x.thermostat, 1, 1)) >= 0 ) {
226 if( write_reg( x.thermostat, 1, val, 1 ) )
227 printk("Failed writing config register\n");
229 /* disable interrupts and TAC input */
230 write_reg( x.fan, 0x01, 0x01, 1 );
232 write_reg( x.fan, 0x23, 0x91, 1 );
233 /* remote temp. controls fan */
234 write_reg( x.fan, 0x00, 0x95, 1 );
236 /* The thermostat (which besides measureing temperature controls
237 * has a THERM output which puts the fan on 100%) is usually
238 * set to kick in at 80 C (chip default). We reduce this a bit
239 * to be on the safe side (OSX doesn't)...
241 if( x.overheat_temp == (80 << 8) ) {
242 x.overheat_temp = 65 << 8;
243 x.overheat_hyst = 60 << 8;
244 write_reg( x.thermostat, 2, x.overheat_hyst, 2 );
245 write_reg( x.thermostat, 3, x.overheat_temp, 2 );
247 print_temp("Reducing overheating limit to ", x.overheat_temp );
248 print_temp(" (Hyst: ", x.overheat_hyst );
252 /* set an initial fan setting */
255 /* tune_fan( fan_up_table[x.upind].fan_setting ); */
257 err = device_create_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
258 err |= device_create_file( &x.of_dev->dev, &dev_attr_case_temperature );
261 "Failed to create temperature attribute file(s).\n");
267 device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
268 device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature );
270 write_reg( x.fan, 0x01, x.r1, 1 );
271 write_reg( x.fan, 0x20, x.r20, 1 );
272 write_reg( x.fan, 0x23, x.r23, 1 );
273 write_reg( x.fan, 0x25, x.r25, 1 );
274 write_reg( x.fan, 0x00, x.r0, 1 );
277 static int control_loop(void *dummy)
281 mutex_unlock(&x.lock);
284 msleep_interruptible(8000);
285 if (kthread_should_stop())
290 mutex_unlock(&x.lock);
295 mutex_unlock(&x.lock);
301 /************************************************************************/
302 /* i2c probing and setup */
303 /************************************************************************/
306 do_attach( struct i2c_adapter *adapter )
308 /* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
309 static const unsigned short scan_ds1775[] = {
310 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
313 static const unsigned short scan_adm1030[] = {
314 0x2c, 0x2d, 0x2e, 0x2f,
318 if( strncmp(adapter->name, "uni-n", 5) )
322 struct i2c_board_info info;
324 memset(&info, 0, sizeof(struct i2c_board_info));
325 strlcpy(info.type, "therm_ds1775", I2C_NAME_SIZE);
326 i2c_new_probed_device(adapter, &info, scan_ds1775);
328 strlcpy(info.type, "therm_adm1030", I2C_NAME_SIZE);
329 i2c_new_probed_device(adapter, &info, scan_adm1030);
331 if( x.thermostat && x.fan ) {
333 x.poll_task = kthread_run(control_loop, NULL, "g4fand");
340 do_remove(struct i2c_client *client)
344 kthread_stop(x.poll_task);
347 if (client == x.thermostat)
349 else if (client == x.fan)
352 printk(KERN_ERR "g4fan: bad client\n");
358 attach_fan( struct i2c_client *cl )
363 /* check that this is an ADM1030 */
364 if( read_reg(cl, 0x3d, 1) != 0x30 || read_reg(cl, 0x3e, 1) != 0x41 )
366 printk("ADM1030 fan controller [@%02x]\n", cl->addr );
374 attach_thermostat( struct i2c_client *cl )
376 int hyst_temp, os_temp, temp;
381 if( (temp=read_reg(cl, 0, 2)) < 0 )
384 /* temperature sanity check */
385 if( temp < 0x1600 || temp > 0x3c00 )
387 hyst_temp = read_reg(cl, 2, 2);
388 os_temp = read_reg(cl, 3, 2);
389 if( hyst_temp < 0 || os_temp < 0 )
392 printk("DS1775 digital thermometer [@%02x]\n", cl->addr );
393 print_temp("Temp: ", temp );
394 print_temp(" Hyst: ", hyst_temp );
395 print_temp(" OS: ", os_temp );
399 x.overheat_temp = os_temp;
400 x.overheat_hyst = hyst_temp;
406 enum chip { ds1775, adm1030 };
408 static const struct i2c_device_id therm_windtunnel_id[] = {
409 { "therm_ds1775", ds1775 },
410 { "therm_adm1030", adm1030 },
415 do_probe(struct i2c_client *cl, const struct i2c_device_id *id)
417 struct i2c_adapter *adapter = cl->adapter;
419 if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA
420 | I2C_FUNC_SMBUS_WRITE_BYTE) )
423 switch (id->driver_data) {
425 return attach_fan( cl );
427 return attach_thermostat(cl);
432 static struct i2c_driver g4fan_driver = {
434 .name = "therm_windtunnel",
436 .attach_adapter = do_attach,
439 .id_table = therm_windtunnel_id,
443 /************************************************************************/
444 /* initialization / cleanup */
445 /************************************************************************/
448 therm_of_probe( struct of_device *dev, const struct of_device_id *match )
450 return i2c_add_driver( &g4fan_driver );
454 therm_of_remove( struct of_device *dev )
456 i2c_del_driver( &g4fan_driver );
460 static struct of_device_id therm_of_match[] = {{
462 .compatible = "adm1030"
466 static struct of_platform_driver therm_of_driver = {
467 .name = "temperature",
468 .match_table = therm_of_match,
469 .probe = therm_of_probe,
470 .remove = therm_of_remove,
473 struct apple_thermal_info {
474 u8 id; /* implementation ID */
475 u8 fan_count; /* number of fans */
476 u8 thermostat_count; /* number of thermostats */
483 const struct apple_thermal_info *info;
484 struct device_node *np;
488 if( !(np=of_find_node_by_name(NULL, "power-mgt")) )
490 info = of_get_property(np, "thermal-info", NULL);
493 if( !info || !machine_is_compatible("PowerMac3,6") )
496 if( info->id != 3 ) {
497 printk(KERN_ERR "therm_windtunnel: unsupported thermal design %d\n", info->id );
500 if( !(np=of_find_node_by_name(NULL, "fan")) )
502 x.of_dev = of_platform_device_create(np, "temperature", NULL);
506 printk(KERN_ERR "Can't register fan controller!\n");
510 of_register_platform_driver( &therm_of_driver );
517 of_unregister_platform_driver( &therm_of_driver );
520 of_device_unregister( x.of_dev );
523 module_init(g4fan_init);
524 module_exit(g4fan_exit);
526 MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>");
527 MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller");
528 MODULE_LICENSE("GPL");