blob: 3da0a02efd7668f6088dd28eb05f88b7c1d0b768 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Linus Torvalds1da177e2005-04-16 15:20:36 -070030#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>
Paul Mackerras98f67402007-12-13 15:57:45 +110039#include <linux/kthread.h>
Stephen Rothwellad9e05a2008-05-23 16:27:02 +100040#include <linux/of_platform.h>
Benjamin Herrenschmidt7eebde72006-11-11 17:24:59 +110041
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <asm/prom.h>
43#include <asm/machdep.h>
44#include <asm/io.h>
45#include <asm/system.h>
46#include <asm/sections.h>
Jeff Mahoney5e655772005-07-06 15:44:41 -040047#include <asm/macio.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
49#define LOG_TEMP 0 /* continously log temperature */
50
Linus Torvalds1da177e2005-04-16 15:20:36 -070051static int do_probe( struct i2c_adapter *adapter, int addr, int kind);
52
53/* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
Jean Delvare2cdddeb2008-01-27 18:14:47 +010054static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
Jean Delvareb3d54962005-04-02 20:31:02 +020055 0x4c, 0x4d, 0x4e, 0x4f,
56 0x2c, 0x2d, 0x2e, 0x2f,
57 I2C_CLIENT_END };
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
59I2C_CLIENT_INSMOD;
60
61static struct {
62 volatile int running;
Paul Mackerras98f67402007-12-13 15:57:45 +110063 struct task_struct *poll_task;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
Daniel Walker1baaeea2008-06-10 09:26:08 +100065 struct mutex lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -070066 struct of_device *of_dev;
67
68 struct i2c_client *thermostat;
69 struct i2c_client *fan;
70
71 int overheat_temp; /* 100% fan at this temp */
72 int overheat_hyst;
73 int temp;
74 int casetemp;
75 int fan_level; /* active fan_table setting */
76
77 int downind;
78 int upind;
79
80 int r0, r1, r20, r23, r25; /* saved register */
81} x;
82
83#define T(x,y) (((x)<<8) | (y)*0x100/10 )
84
85static struct {
86 int fan_down_setting;
87 int temp;
88 int fan_up_setting;
89} fan_table[] = {
90 { 11, T(0,0), 11 }, /* min fan */
91 { 11, T(55,0), 11 },
92 { 6, T(55,3), 11 },
93 { 7, T(56,0), 11 },
94 { 8, T(57,0), 8 },
95 { 7, T(58,3), 7 },
96 { 6, T(58,8), 6 },
97 { 5, T(59,2), 5 },
98 { 4, T(59,6), 4 },
99 { 3, T(59,9), 3 },
100 { 2, T(60,1), 2 },
101 { 1, 0xfffff, 1 } /* on fire */
102};
103
104static void
105print_temp( const char *s, int temp )
106{
107 printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
108}
109
110static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400111show_cpu_temperature( struct device *dev, struct device_attribute *attr, char *buf )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112{
113 return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 );
114}
115
116static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400117show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118{
119 return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 );
120}
121
122static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL );
123static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );
124
125
126
127/************************************************************************/
128/* controller thread */
129/************************************************************************/
130
131static int
132write_reg( struct i2c_client *cl, int reg, int data, int len )
133{
134 u8 tmp[3];
135
136 if( len < 1 || len > 2 || data < 0 )
137 return -EINVAL;
138
139 tmp[0] = reg;
140 tmp[1] = (len == 1) ? data : (data >> 8);
141 tmp[2] = data;
142 len++;
143
144 if( i2c_master_send(cl, tmp, len) != len )
145 return -ENODEV;
146 return 0;
147}
148
149static int
150read_reg( struct i2c_client *cl, int reg, int len )
151{
152 u8 buf[2];
153
154 if( len != 1 && len != 2 )
155 return -EINVAL;
156 buf[0] = reg;
157 if( i2c_master_send(cl, buf, 1) != 1 )
158 return -ENODEV;
159 if( i2c_master_recv(cl, buf, len) != len )
160 return -ENODEV;
161 return (len == 2)? ((unsigned int)buf[0] << 8) | buf[1] : buf[0];
162}
163
164static void
165tune_fan( int fan_setting )
166{
167 int val = (fan_setting << 3) | 7;
168
169 /* write_reg( x.fan, 0x24, val, 1 ); */
170 write_reg( x.fan, 0x25, val, 1 );
171 write_reg( x.fan, 0x20, 0, 1 );
172 print_temp("CPU-temp: ", x.temp );
173 if( x.casetemp )
174 print_temp(", Case: ", x.casetemp );
175 printk(", Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting );
176
177 x.fan_level = fan_setting;
178}
179
180static void
181poll_temp( void )
182{
183 int temp, i, level, casetemp;
184
185 temp = read_reg( x.thermostat, 0, 2 );
186
187 /* this actually occurs when the computer is loaded */
188 if( temp < 0 )
189 return;
190
191 casetemp = read_reg(x.fan, 0x0b, 1) << 8;
192 casetemp |= (read_reg(x.fan, 0x06, 1) & 0x7) << 5;
193
194 if( LOG_TEMP && x.temp != temp ) {
195 print_temp("CPU-temp: ", temp );
196 print_temp(", Case: ", casetemp );
197 printk(", Fan: %d\n", 11-x.fan_level );
198 }
199 x.temp = temp;
200 x.casetemp = casetemp;
201
202 level = -1;
203 for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ )
204 ;
205 if( i < x.downind )
206 level = fan_table[i].fan_down_setting;
207 x.downind = i;
208
209 for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ )
210 ;
211 if( x.upind < i )
212 level = fan_table[i].fan_up_setting;
213 x.upind = i;
214
215 if( level >= 0 )
216 tune_fan( level );
217}
218
219
220static void
221setup_hardware( void )
222{
223 int val;
Stephen Rothwell98894df2008-01-03 15:15:28 +1100224 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225
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
Stephen Rothwell98894df2008-01-03 15:15:28 +1100267 err = device_create_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
268 err |= device_create_file( &x.of_dev->dev, &dev_attr_case_temperature );
269 if (err)
270 printk(KERN_WARNING
271 "Failed to create temperature attribute file(s).\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272}
273
274static void
275restore_regs( void )
276{
277 device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
278 device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature );
279
280 write_reg( x.fan, 0x01, x.r1, 1 );
281 write_reg( x.fan, 0x20, x.r20, 1 );
282 write_reg( x.fan, 0x23, x.r23, 1 );
283 write_reg( x.fan, 0x25, x.r25, 1 );
284 write_reg( x.fan, 0x00, x.r0, 1 );
285}
286
Paul Mackerras98f67402007-12-13 15:57:45 +1100287static int control_loop(void *dummy)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288{
Daniel Walker1baaeea2008-06-10 09:26:08 +1000289 mutex_lock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 setup_hardware();
Daniel Walker1baaeea2008-06-10 09:26:08 +1000291 mutex_unlock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
Paul Mackerras98f67402007-12-13 15:57:45 +1100293 for (;;) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 msleep_interruptible(8000);
Paul Mackerras98f67402007-12-13 15:57:45 +1100295 if (kthread_should_stop())
296 break;
297
Daniel Walker1baaeea2008-06-10 09:26:08 +1000298 mutex_lock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299 poll_temp();
Daniel Walker1baaeea2008-06-10 09:26:08 +1000300 mutex_unlock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 }
302
Daniel Walker1baaeea2008-06-10 09:26:08 +1000303 mutex_lock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 restore_regs();
Daniel Walker1baaeea2008-06-10 09:26:08 +1000305 mutex_unlock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306
Paul Mackerras98f67402007-12-13 15:57:45 +1100307 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308}
309
310
311/************************************************************************/
312/* i2c probing and setup */
313/************************************************************************/
314
315static int
316do_attach( struct i2c_adapter *adapter )
317{
318 int ret = 0;
319
320 if( strncmp(adapter->name, "uni-n", 5) )
321 return 0;
322
323 if( !x.running ) {
324 ret = i2c_probe( adapter, &addr_data, &do_probe );
325 if( x.thermostat && x.fan ) {
326 x.running = 1;
Paul Mackerras98f67402007-12-13 15:57:45 +1100327 x.poll_task = kthread_run(control_loop, NULL, "g4fand");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 }
329 }
330 return ret;
331}
332
333static int
334do_detach( struct i2c_client *client )
335{
336 int err;
337
338 if( (err=i2c_detach_client(client)) )
339 printk(KERN_ERR "failed to detach thermostat client\n");
340 else {
341 if( x.running ) {
342 x.running = 0;
Paul Mackerras98f67402007-12-13 15:57:45 +1100343 kthread_stop(x.poll_task);
344 x.poll_task = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 }
346 if( client == x.thermostat )
347 x.thermostat = NULL;
348 else if( client == x.fan )
349 x.fan = NULL;
350 else {
351 printk(KERN_ERR "g4fan: bad client\n");
352 }
353 kfree( client );
354 }
355 return err;
356}
357
358static struct i2c_driver g4fan_driver = {
Laurent Riffarda33ca232005-11-26 20:40:34 +0100359 .driver = {
Laurent Riffarda33ca232005-11-26 20:40:34 +0100360 .name = "therm_windtunnel",
361 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 .attach_adapter = do_attach,
363 .detach_client = do_detach,
364};
365
366static int
367attach_fan( struct i2c_client *cl )
368{
369 if( x.fan )
370 goto out;
371
372 /* check that this is an ADM1030 */
373 if( read_reg(cl, 0x3d, 1) != 0x30 || read_reg(cl, 0x3e, 1) != 0x41 )
374 goto out;
375 printk("ADM1030 fan controller [@%02x]\n", cl->addr );
376
377 strlcpy( cl->name, "ADM1030 fan controller", sizeof(cl->name) );
378
379 if( !i2c_attach_client(cl) )
380 x.fan = cl;
381 out:
382 if( cl != x.fan )
383 kfree( cl );
384 return 0;
385}
386
387static int
388attach_thermostat( struct i2c_client *cl )
389{
390 int hyst_temp, os_temp, temp;
391
392 if( x.thermostat )
393 goto out;
394
395 if( (temp=read_reg(cl, 0, 2)) < 0 )
396 goto out;
397
398 /* temperature sanity check */
399 if( temp < 0x1600 || temp > 0x3c00 )
400 goto out;
401 hyst_temp = read_reg(cl, 2, 2);
402 os_temp = read_reg(cl, 3, 2);
403 if( hyst_temp < 0 || os_temp < 0 )
404 goto out;
405
406 printk("DS1775 digital thermometer [@%02x]\n", cl->addr );
407 print_temp("Temp: ", temp );
408 print_temp(" Hyst: ", hyst_temp );
409 print_temp(" OS: ", os_temp );
410 printk("\n");
411
412 x.temp = temp;
413 x.overheat_temp = os_temp;
414 x.overheat_hyst = hyst_temp;
415
416 strlcpy( cl->name, "DS1775 thermostat", sizeof(cl->name) );
417
418 if( !i2c_attach_client(cl) )
419 x.thermostat = cl;
420out:
421 if( cl != x.thermostat )
422 kfree( cl );
423 return 0;
424}
425
426static int
427do_probe( struct i2c_adapter *adapter, int addr, int kind )
428{
429 struct i2c_client *cl;
430
431 if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA
432 | I2C_FUNC_SMBUS_WRITE_BYTE) )
433 return 0;
434
Yoann Padioleaudd00cc42007-07-19 01:49:03 -0700435 if( !(cl=kzalloc(sizeof(*cl), GFP_KERNEL)) )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437
438 cl->addr = addr;
439 cl->adapter = adapter;
440 cl->driver = &g4fan_driver;
441 cl->flags = 0;
442
443 if( addr < 0x48 )
444 return attach_fan( cl );
445 return attach_thermostat( cl );
446}
447
448
449/************************************************************************/
450/* initialization / cleanup */
451/************************************************************************/
452
453static int
Jeff Mahoney5e655772005-07-06 15:44:41 -0400454therm_of_probe( struct of_device *dev, const struct of_device_id *match )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455{
456 return i2c_add_driver( &g4fan_driver );
457}
458
459static int
460therm_of_remove( struct of_device *dev )
461{
Jean Delvareb3e82092007-05-01 23:26:32 +0200462 i2c_del_driver( &g4fan_driver );
463 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464}
465
Jeff Mahoney5e655772005-07-06 15:44:41 -0400466static struct of_device_id therm_of_match[] = {{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 .name = "fan",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 .compatible = "adm1030"
469 }, {}
470};
471
472static struct of_platform_driver therm_of_driver = {
473 .name = "temperature",
474 .match_table = therm_of_match,
475 .probe = therm_of_probe,
476 .remove = therm_of_remove,
477};
478
479struct apple_thermal_info {
480 u8 id; /* implementation ID */
481 u8 fan_count; /* number of fans */
482 u8 thermostat_count; /* number of thermostats */
483 u8 unused;
484};
485
486static int __init
487g4fan_init( void )
488{
Jeremy Kerr018a3d12006-07-12 15:40:29 +1000489 const struct apple_thermal_info *info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 struct device_node *np;
491
Daniel Walker1baaeea2008-06-10 09:26:08 +1000492 mutex_init(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493
494 if( !(np=of_find_node_by_name(NULL, "power-mgt")) )
495 return -ENODEV;
Stephen Rothwell01b27262007-04-27 13:41:15 +1000496 info = of_get_property(np, "thermal-info", NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 of_node_put(np);
498
499 if( !info || !machine_is_compatible("PowerMac3,6") )
500 return -ENODEV;
501
502 if( info->id != 3 ) {
503 printk(KERN_ERR "therm_windtunnel: unsupported thermal design %d\n", info->id );
504 return -ENODEV;
505 }
506 if( !(np=of_find_node_by_name(NULL, "fan")) )
507 return -ENODEV;
Benjamin Herrenschmidt0365ba72005-09-22 21:44:06 -0700508 x.of_dev = of_platform_device_create(np, "temperature", NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509 of_node_put( np );
510
511 if( !x.of_dev ) {
512 printk(KERN_ERR "Can't register fan controller!\n");
513 return -ENODEV;
514 }
515
Benjamin Herrenschmidt7eebde72006-11-11 17:24:59 +1100516 of_register_platform_driver( &therm_of_driver );
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 return 0;
518}
519
520static void __exit
521g4fan_exit( void )
522{
Benjamin Herrenschmidt7eebde72006-11-11 17:24:59 +1100523 of_unregister_platform_driver( &therm_of_driver );
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524
525 if( x.of_dev )
526 of_device_unregister( x.of_dev );
527}
528
529module_init(g4fan_init);
530module_exit(g4fan_exit);
531
532MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>");
533MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller");
534MODULE_LICENSE("GPL");