blob: 3d9dd2e166aab2562d2f85dafc165459156afbf7 [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
30#include <linux/config.h>
31#include <linux/types.h>
32#include <linux/module.h>
33#include <linux/errno.h>
34#include <linux/kernel.h>
35#include <linux/delay.h>
36#include <linux/sched.h>
37#include <linux/i2c.h>
38#include <linux/slab.h>
39#include <linux/init.h>
40#include <asm/prom.h>
41#include <asm/machdep.h>
42#include <asm/io.h>
43#include <asm/system.h>
44#include <asm/sections.h>
45#include <asm/of_device.h>
Jeff Mahoney5e655772005-07-06 15:44:41 -040046#include <asm/macio.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070047
48#define LOG_TEMP 0 /* continously log temperature */
49
50#define I2C_DRIVERID_G4FAN 0x9001 /* fixme */
51
52static int do_probe( struct i2c_adapter *adapter, int addr, int kind);
53
54/* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
Jean Delvareb3d5496e2005-04-02 20:31:02 +020055static unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
56 0x4c, 0x4d, 0x4e, 0x4f,
57 0x2c, 0x2d, 0x2e, 0x2f,
58 I2C_CLIENT_END };
Linus Torvalds1da177e2005-04-16 15:20:36 -070059
60I2C_CLIENT_INSMOD;
61
62static struct {
63 volatile int running;
64 struct completion completion;
65 pid_t poll_task;
66
67 struct semaphore lock;
68 struct of_device *of_dev;
69
70 struct i2c_client *thermostat;
71 struct i2c_client *fan;
72
73 int overheat_temp; /* 100% fan at this temp */
74 int overheat_hyst;
75 int temp;
76 int casetemp;
77 int fan_level; /* active fan_table setting */
78
79 int downind;
80 int upind;
81
82 int r0, r1, r20, r23, r25; /* saved register */
83} x;
84
85#define T(x,y) (((x)<<8) | (y)*0x100/10 )
86
87static struct {
88 int fan_down_setting;
89 int temp;
90 int fan_up_setting;
91} fan_table[] = {
92 { 11, T(0,0), 11 }, /* min fan */
93 { 11, T(55,0), 11 },
94 { 6, T(55,3), 11 },
95 { 7, T(56,0), 11 },
96 { 8, T(57,0), 8 },
97 { 7, T(58,3), 7 },
98 { 6, T(58,8), 6 },
99 { 5, T(59,2), 5 },
100 { 4, T(59,6), 4 },
101 { 3, T(59,9), 3 },
102 { 2, T(60,1), 2 },
103 { 1, 0xfffff, 1 } /* on fire */
104};
105
106static void
107print_temp( const char *s, int temp )
108{
109 printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
110}
111
112static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400113show_cpu_temperature( struct device *dev, struct device_attribute *attr, char *buf )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114{
115 return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 );
116}
117
118static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400119show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120{
121 return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 );
122}
123
124static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL );
125static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );
126
127
128
129/************************************************************************/
130/* controller thread */
131/************************************************************************/
132
133static int
134write_reg( struct i2c_client *cl, int reg, int data, int len )
135{
136 u8 tmp[3];
137
138 if( len < 1 || len > 2 || data < 0 )
139 return -EINVAL;
140
141 tmp[0] = reg;
142 tmp[1] = (len == 1) ? data : (data >> 8);
143 tmp[2] = data;
144 len++;
145
146 if( i2c_master_send(cl, tmp, len) != len )
147 return -ENODEV;
148 return 0;
149}
150
151static int
152read_reg( struct i2c_client *cl, int reg, int len )
153{
154 u8 buf[2];
155
156 if( len != 1 && len != 2 )
157 return -EINVAL;
158 buf[0] = reg;
159 if( i2c_master_send(cl, buf, 1) != 1 )
160 return -ENODEV;
161 if( i2c_master_recv(cl, buf, len) != len )
162 return -ENODEV;
163 return (len == 2)? ((unsigned int)buf[0] << 8) | buf[1] : buf[0];
164}
165
166static void
167tune_fan( int fan_setting )
168{
169 int val = (fan_setting << 3) | 7;
170
171 /* write_reg( x.fan, 0x24, val, 1 ); */
172 write_reg( x.fan, 0x25, val, 1 );
173 write_reg( x.fan, 0x20, 0, 1 );
174 print_temp("CPU-temp: ", x.temp );
175 if( x.casetemp )
176 print_temp(", Case: ", x.casetemp );
177 printk(", Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting );
178
179 x.fan_level = fan_setting;
180}
181
182static void
183poll_temp( void )
184{
185 int temp, i, level, casetemp;
186
187 temp = read_reg( x.thermostat, 0, 2 );
188
189 /* this actually occurs when the computer is loaded */
190 if( temp < 0 )
191 return;
192
193 casetemp = read_reg(x.fan, 0x0b, 1) << 8;
194 casetemp |= (read_reg(x.fan, 0x06, 1) & 0x7) << 5;
195
196 if( LOG_TEMP && x.temp != temp ) {
197 print_temp("CPU-temp: ", temp );
198 print_temp(", Case: ", casetemp );
199 printk(", Fan: %d\n", 11-x.fan_level );
200 }
201 x.temp = temp;
202 x.casetemp = casetemp;
203
204 level = -1;
205 for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ )
206 ;
207 if( i < x.downind )
208 level = fan_table[i].fan_down_setting;
209 x.downind = i;
210
211 for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ )
212 ;
213 if( x.upind < i )
214 level = fan_table[i].fan_up_setting;
215 x.upind = i;
216
217 if( level >= 0 )
218 tune_fan( level );
219}
220
221
222static void
223setup_hardware( void )
224{
225 int val;
226
227 /* save registers (if we unload the module) */
228 x.r0 = read_reg( x.fan, 0x00, 1 );
229 x.r1 = read_reg( x.fan, 0x01, 1 );
230 x.r20 = read_reg( x.fan, 0x20, 1 );
231 x.r23 = read_reg( x.fan, 0x23, 1 );
232 x.r25 = read_reg( x.fan, 0x25, 1 );
233
234 /* improve measurement resolution (convergence time 1.5s) */
235 if( (val=read_reg(x.thermostat, 1, 1)) >= 0 ) {
236 val |= 0x60;
237 if( write_reg( x.thermostat, 1, val, 1 ) )
238 printk("Failed writing config register\n");
239 }
240 /* disable interrupts and TAC input */
241 write_reg( x.fan, 0x01, 0x01, 1 );
242 /* enable filter */
243 write_reg( x.fan, 0x23, 0x91, 1 );
244 /* remote temp. controls fan */
245 write_reg( x.fan, 0x00, 0x95, 1 );
246
247 /* The thermostat (which besides measureing temperature controls
248 * has a THERM output which puts the fan on 100%) is usually
249 * set to kick in at 80 C (chip default). We reduce this a bit
250 * to be on the safe side (OSX doesn't)...
251 */
252 if( x.overheat_temp == (80 << 8) ) {
253 x.overheat_temp = 65 << 8;
254 x.overheat_hyst = 60 << 8;
255 write_reg( x.thermostat, 2, x.overheat_hyst, 2 );
256 write_reg( x.thermostat, 3, x.overheat_temp, 2 );
257
258 print_temp("Reducing overheating limit to ", x.overheat_temp );
259 print_temp(" (Hyst: ", x.overheat_hyst );
260 printk(")\n");
261 }
262
263 /* set an initial fan setting */
264 x.downind = 0xffff;
265 x.upind = -1;
266 /* tune_fan( fan_up_table[x.upind].fan_setting ); */
267
268 device_create_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
269 device_create_file( &x.of_dev->dev, &dev_attr_case_temperature );
270}
271
272static void
273restore_regs( void )
274{
275 device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
276 device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature );
277
278 write_reg( x.fan, 0x01, x.r1, 1 );
279 write_reg( x.fan, 0x20, x.r20, 1 );
280 write_reg( x.fan, 0x23, x.r23, 1 );
281 write_reg( x.fan, 0x25, x.r25, 1 );
282 write_reg( x.fan, 0x00, x.r0, 1 );
283}
284
285static int
286control_loop( void *dummy )
287{
288 daemonize("g4fand");
289
290 down( &x.lock );
291 setup_hardware();
292
293 while( x.running ) {
294 up( &x.lock );
295
296 msleep_interruptible(8000);
297
298 down( &x.lock );
299 poll_temp();
300 }
301
302 restore_regs();
303 up( &x.lock );
304
305 complete_and_exit( &x.completion, 0 );
306}
307
308
309/************************************************************************/
310/* i2c probing and setup */
311/************************************************************************/
312
313static int
314do_attach( struct i2c_adapter *adapter )
315{
316 int ret = 0;
317
318 if( strncmp(adapter->name, "uni-n", 5) )
319 return 0;
320
321 if( !x.running ) {
322 ret = i2c_probe( adapter, &addr_data, &do_probe );
323 if( x.thermostat && x.fan ) {
324 x.running = 1;
325 init_completion( &x.completion );
326 x.poll_task = kernel_thread( control_loop, NULL, SIGCHLD | CLONE_KERNEL );
327 }
328 }
329 return ret;
330}
331
332static int
333do_detach( struct i2c_client *client )
334{
335 int err;
336
337 if( (err=i2c_detach_client(client)) )
338 printk(KERN_ERR "failed to detach thermostat client\n");
339 else {
340 if( x.running ) {
341 x.running = 0;
342 wait_for_completion( &x.completion );
343 }
344 if( client == x.thermostat )
345 x.thermostat = NULL;
346 else if( client == x.fan )
347 x.fan = NULL;
348 else {
349 printk(KERN_ERR "g4fan: bad client\n");
350 }
351 kfree( client );
352 }
353 return err;
354}
355
356static struct i2c_driver g4fan_driver = {
Laurent Riffarda33ca232005-11-26 20:40:34 +0100357 .driver = {
Laurent Riffarda33ca232005-11-26 20:40:34 +0100358 .name = "therm_windtunnel",
359 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 .id = I2C_DRIVERID_G4FAN,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 .attach_adapter = do_attach,
362 .detach_client = do_detach,
363};
364
365static int
366attach_fan( struct i2c_client *cl )
367{
368 if( x.fan )
369 goto out;
370
371 /* check that this is an ADM1030 */
372 if( read_reg(cl, 0x3d, 1) != 0x30 || read_reg(cl, 0x3e, 1) != 0x41 )
373 goto out;
374 printk("ADM1030 fan controller [@%02x]\n", cl->addr );
375
376 strlcpy( cl->name, "ADM1030 fan controller", sizeof(cl->name) );
377
378 if( !i2c_attach_client(cl) )
379 x.fan = cl;
380 out:
381 if( cl != x.fan )
382 kfree( cl );
383 return 0;
384}
385
386static int
387attach_thermostat( struct i2c_client *cl )
388{
389 int hyst_temp, os_temp, temp;
390
391 if( x.thermostat )
392 goto out;
393
394 if( (temp=read_reg(cl, 0, 2)) < 0 )
395 goto out;
396
397 /* temperature sanity check */
398 if( temp < 0x1600 || temp > 0x3c00 )
399 goto out;
400 hyst_temp = read_reg(cl, 2, 2);
401 os_temp = read_reg(cl, 3, 2);
402 if( hyst_temp < 0 || os_temp < 0 )
403 goto out;
404
405 printk("DS1775 digital thermometer [@%02x]\n", cl->addr );
406 print_temp("Temp: ", temp );
407 print_temp(" Hyst: ", hyst_temp );
408 print_temp(" OS: ", os_temp );
409 printk("\n");
410
411 x.temp = temp;
412 x.overheat_temp = os_temp;
413 x.overheat_hyst = hyst_temp;
414
415 strlcpy( cl->name, "DS1775 thermostat", sizeof(cl->name) );
416
417 if( !i2c_attach_client(cl) )
418 x.thermostat = cl;
419out:
420 if( cl != x.thermostat )
421 kfree( cl );
422 return 0;
423}
424
425static int
426do_probe( struct i2c_adapter *adapter, int addr, int kind )
427{
428 struct i2c_client *cl;
429
430 if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA
431 | I2C_FUNC_SMBUS_WRITE_BYTE) )
432 return 0;
433
434 if( !(cl=kmalloc(sizeof(*cl), GFP_KERNEL)) )
435 return -ENOMEM;
436 memset( cl, 0, sizeof(struct i2c_client) );
437
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{
462 return i2c_del_driver( &g4fan_driver );
463}
464
Jeff Mahoney5e655772005-07-06 15:44:41 -0400465static struct of_device_id therm_of_match[] = {{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 .name = "fan",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 .compatible = "adm1030"
468 }, {}
469};
470
471static struct of_platform_driver therm_of_driver = {
472 .name = "temperature",
473 .match_table = therm_of_match,
474 .probe = therm_of_probe,
475 .remove = therm_of_remove,
476};
477
478struct apple_thermal_info {
479 u8 id; /* implementation ID */
480 u8 fan_count; /* number of fans */
481 u8 thermostat_count; /* number of thermostats */
482 u8 unused;
483};
484
485static int __init
486g4fan_init( void )
487{
488 struct apple_thermal_info *info;
489 struct device_node *np;
490
491 init_MUTEX( &x.lock );
492
493 if( !(np=of_find_node_by_name(NULL, "power-mgt")) )
494 return -ENODEV;
495 info = (struct apple_thermal_info*)get_property(np, "thermal-info", NULL);
496 of_node_put(np);
497
498 if( !info || !machine_is_compatible("PowerMac3,6") )
499 return -ENODEV;
500
501 if( info->id != 3 ) {
502 printk(KERN_ERR "therm_windtunnel: unsupported thermal design %d\n", info->id );
503 return -ENODEV;
504 }
505 if( !(np=of_find_node_by_name(NULL, "fan")) )
506 return -ENODEV;
Benjamin Herrenschmidt0365ba72005-09-22 21:44:06 -0700507 x.of_dev = of_platform_device_create(np, "temperature", NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 of_node_put( np );
509
510 if( !x.of_dev ) {
511 printk(KERN_ERR "Can't register fan controller!\n");
512 return -ENODEV;
513 }
514
515 of_register_driver( &therm_of_driver );
516 return 0;
517}
518
519static void __exit
520g4fan_exit( void )
521{
522 of_unregister_driver( &therm_of_driver );
523
524 if( x.of_dev )
525 of_device_unregister( x.of_dev );
526}
527
528module_init(g4fan_init);
529module_exit(g4fan_exit);
530
531MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>");
532MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller");
533MODULE_LICENSE("GPL");