blob: 8b9364434aa0bbd21995c9b299c021075fabfb30 [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 struct {
52 volatile int running;
Paul Mackerras98f67402007-12-13 15:57:45 +110053 struct task_struct *poll_task;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
Daniel Walker1baaeea2008-06-10 09:26:08 +100055 struct mutex lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -070056 struct of_device *of_dev;
57
58 struct i2c_client *thermostat;
59 struct i2c_client *fan;
60
61 int overheat_temp; /* 100% fan at this temp */
62 int overheat_hyst;
63 int temp;
64 int casetemp;
65 int fan_level; /* active fan_table setting */
66
67 int downind;
68 int upind;
69
70 int r0, r1, r20, r23, r25; /* saved register */
71} x;
72
73#define T(x,y) (((x)<<8) | (y)*0x100/10 )
74
75static struct {
76 int fan_down_setting;
77 int temp;
78 int fan_up_setting;
79} fan_table[] = {
80 { 11, T(0,0), 11 }, /* min fan */
81 { 11, T(55,0), 11 },
82 { 6, T(55,3), 11 },
83 { 7, T(56,0), 11 },
84 { 8, T(57,0), 8 },
85 { 7, T(58,3), 7 },
86 { 6, T(58,8), 6 },
87 { 5, T(59,2), 5 },
88 { 4, T(59,6), 4 },
89 { 3, T(59,9), 3 },
90 { 2, T(60,1), 2 },
91 { 1, 0xfffff, 1 } /* on fire */
92};
93
94static void
95print_temp( const char *s, int temp )
96{
97 printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
98}
99
100static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400101show_cpu_temperature( struct device *dev, struct device_attribute *attr, char *buf )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102{
103 return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 );
104}
105
106static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400107show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108{
109 return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 );
110}
111
112static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL );
113static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );
114
115
116
117/************************************************************************/
118/* controller thread */
119/************************************************************************/
120
121static int
122write_reg( struct i2c_client *cl, int reg, int data, int len )
123{
124 u8 tmp[3];
125
126 if( len < 1 || len > 2 || data < 0 )
127 return -EINVAL;
128
129 tmp[0] = reg;
130 tmp[1] = (len == 1) ? data : (data >> 8);
131 tmp[2] = data;
132 len++;
133
134 if( i2c_master_send(cl, tmp, len) != len )
135 return -ENODEV;
136 return 0;
137}
138
139static int
140read_reg( struct i2c_client *cl, int reg, int len )
141{
142 u8 buf[2];
143
144 if( len != 1 && len != 2 )
145 return -EINVAL;
146 buf[0] = reg;
147 if( i2c_master_send(cl, buf, 1) != 1 )
148 return -ENODEV;
149 if( i2c_master_recv(cl, buf, len) != len )
150 return -ENODEV;
151 return (len == 2)? ((unsigned int)buf[0] << 8) | buf[1] : buf[0];
152}
153
154static void
155tune_fan( int fan_setting )
156{
157 int val = (fan_setting << 3) | 7;
158
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 );
163 if( x.casetemp )
164 print_temp(", Case: ", x.casetemp );
165 printk(", Fan: %d (tuned %+d)\n", 11-fan_setting, x.fan_level-fan_setting );
166
167 x.fan_level = fan_setting;
168}
169
170static void
171poll_temp( void )
172{
173 int temp, i, level, casetemp;
174
175 temp = read_reg( x.thermostat, 0, 2 );
176
177 /* this actually occurs when the computer is loaded */
178 if( temp < 0 )
179 return;
180
181 casetemp = read_reg(x.fan, 0x0b, 1) << 8;
182 casetemp |= (read_reg(x.fan, 0x06, 1) & 0x7) << 5;
183
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 );
188 }
189 x.temp = temp;
190 x.casetemp = casetemp;
191
192 level = -1;
193 for( i=0; (temp & 0xffff) > fan_table[i].temp ; i++ )
194 ;
195 if( i < x.downind )
196 level = fan_table[i].fan_down_setting;
197 x.downind = i;
198
199 for( i=0; (temp & 0xffff) >= fan_table[i+1].temp ; i++ )
200 ;
201 if( x.upind < i )
202 level = fan_table[i].fan_up_setting;
203 x.upind = i;
204
205 if( level >= 0 )
206 tune_fan( level );
207}
208
209
210static void
211setup_hardware( void )
212{
213 int val;
Stephen Rothwell98894df2008-01-03 15:15:28 +1100214 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215
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 );
222
223 /* improve measurement resolution (convergence time 1.5s) */
224 if( (val=read_reg(x.thermostat, 1, 1)) >= 0 ) {
225 val |= 0x60;
226 if( write_reg( x.thermostat, 1, val, 1 ) )
227 printk("Failed writing config register\n");
228 }
229 /* disable interrupts and TAC input */
230 write_reg( x.fan, 0x01, 0x01, 1 );
231 /* enable filter */
232 write_reg( x.fan, 0x23, 0x91, 1 );
233 /* remote temp. controls fan */
234 write_reg( x.fan, 0x00, 0x95, 1 );
235
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)...
240 */
241 if( x.overheat_temp == (80 << 8) ) {
Lyonel Vincentb8e4a7d2009-08-30 08:54:20 +0000242 x.overheat_temp = 75 << 8;
243 x.overheat_hyst = 70 << 8;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 write_reg( x.thermostat, 2, x.overheat_hyst, 2 );
245 write_reg( x.thermostat, 3, x.overheat_temp, 2 );
246
247 print_temp("Reducing overheating limit to ", x.overheat_temp );
248 print_temp(" (Hyst: ", x.overheat_hyst );
249 printk(")\n");
250 }
251
252 /* set an initial fan setting */
253 x.downind = 0xffff;
254 x.upind = -1;
255 /* tune_fan( fan_up_table[x.upind].fan_setting ); */
256
Stephen Rothwell98894df2008-01-03 15:15:28 +1100257 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 );
259 if (err)
260 printk(KERN_WARNING
261 "Failed to create temperature attribute file(s).\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262}
263
264static void
265restore_regs( void )
266{
267 device_remove_file( &x.of_dev->dev, &dev_attr_cpu_temperature );
268 device_remove_file( &x.of_dev->dev, &dev_attr_case_temperature );
269
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 );
275}
276
Paul Mackerras98f67402007-12-13 15:57:45 +1100277static int control_loop(void *dummy)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278{
Daniel Walker1baaeea2008-06-10 09:26:08 +1000279 mutex_lock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 setup_hardware();
Daniel Walker1baaeea2008-06-10 09:26:08 +1000281 mutex_unlock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282
Paul Mackerras98f67402007-12-13 15:57:45 +1100283 for (;;) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 msleep_interruptible(8000);
Paul Mackerras98f67402007-12-13 15:57:45 +1100285 if (kthread_should_stop())
286 break;
287
Daniel Walker1baaeea2008-06-10 09:26:08 +1000288 mutex_lock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 poll_temp();
Daniel Walker1baaeea2008-06-10 09:26:08 +1000290 mutex_unlock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 }
292
Daniel Walker1baaeea2008-06-10 09:26:08 +1000293 mutex_lock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 restore_regs();
Daniel Walker1baaeea2008-06-10 09:26:08 +1000295 mutex_unlock(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296
Paul Mackerras98f67402007-12-13 15:57:45 +1100297 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298}
299
300
301/************************************************************************/
302/* i2c probing and setup */
303/************************************************************************/
304
305static int
306do_attach( struct i2c_adapter *adapter )
307{
Jean Delvare036533e2009-06-15 18:01:52 +0200308 /* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
309 static const unsigned short scan_ds1775[] = {
310 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
311 I2C_CLIENT_END
312 };
313 static const unsigned short scan_adm1030[] = {
314 0x2c, 0x2d, 0x2e, 0x2f,
315 I2C_CLIENT_END
316 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317
318 if( strncmp(adapter->name, "uni-n", 5) )
319 return 0;
320
321 if( !x.running ) {
Jean Delvare036533e2009-06-15 18:01:52 +0200322 struct i2c_board_info info;
323
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);
327
328 strlcpy(info.type, "therm_adm1030", I2C_NAME_SIZE);
329 i2c_new_probed_device(adapter, &info, scan_adm1030);
330
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331 if( x.thermostat && x.fan ) {
332 x.running = 1;
Paul Mackerras98f67402007-12-13 15:57:45 +1100333 x.poll_task = kthread_run(control_loop, NULL, "g4fand");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 }
335 }
Jean Delvare036533e2009-06-15 18:01:52 +0200336 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337}
338
339static int
Jean Delvare036533e2009-06-15 18:01:52 +0200340do_remove(struct i2c_client *client)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341{
Jean Delvare036533e2009-06-15 18:01:52 +0200342 if (x.running) {
343 x.running = 0;
344 kthread_stop(x.poll_task);
345 x.poll_task = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 }
Jean Delvare036533e2009-06-15 18:01:52 +0200347 if (client == x.thermostat)
348 x.thermostat = NULL;
349 else if (client == x.fan)
350 x.fan = NULL;
351 else
352 printk(KERN_ERR "g4fan: bad client\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353
Jean Delvare036533e2009-06-15 18:01:52 +0200354 return 0;
355}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
357static int
358attach_fan( struct i2c_client *cl )
359{
360 if( x.fan )
361 goto out;
362
363 /* check that this is an ADM1030 */
364 if( read_reg(cl, 0x3d, 1) != 0x30 || read_reg(cl, 0x3e, 1) != 0x41 )
365 goto out;
366 printk("ADM1030 fan controller [@%02x]\n", cl->addr );
367
Jean Delvare036533e2009-06-15 18:01:52 +0200368 x.fan = cl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 return 0;
371}
372
373static int
374attach_thermostat( struct i2c_client *cl )
375{
376 int hyst_temp, os_temp, temp;
377
378 if( x.thermostat )
379 goto out;
380
381 if( (temp=read_reg(cl, 0, 2)) < 0 )
382 goto out;
383
384 /* temperature sanity check */
385 if( temp < 0x1600 || temp > 0x3c00 )
386 goto out;
387 hyst_temp = read_reg(cl, 2, 2);
388 os_temp = read_reg(cl, 3, 2);
389 if( hyst_temp < 0 || os_temp < 0 )
390 goto out;
391
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 );
396 printk("\n");
397
398 x.temp = temp;
399 x.overheat_temp = os_temp;
400 x.overheat_hyst = hyst_temp;
Jean Delvare036533e2009-06-15 18:01:52 +0200401 x.thermostat = cl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 return 0;
404}
405
Jean Delvare036533e2009-06-15 18:01:52 +0200406enum chip { ds1775, adm1030 };
407
408static const struct i2c_device_id therm_windtunnel_id[] = {
409 { "therm_ds1775", ds1775 },
410 { "therm_adm1030", adm1030 },
411 { }
412};
413
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414static int
Jean Delvare036533e2009-06-15 18:01:52 +0200415do_probe(struct i2c_client *cl, const struct i2c_device_id *id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416{
Jean Delvare036533e2009-06-15 18:01:52 +0200417 struct i2c_adapter *adapter = cl->adapter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418
419 if( !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA
420 | I2C_FUNC_SMBUS_WRITE_BYTE) )
421 return 0;
422
Jean Delvare036533e2009-06-15 18:01:52 +0200423 switch (id->driver_data) {
424 case adm1030:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700425 return attach_fan( cl );
Jean Delvare036533e2009-06-15 18:01:52 +0200426 case ds1775:
427 return attach_thermostat(cl);
428 }
429 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430}
431
Jean Delvare036533e2009-06-15 18:01:52 +0200432static struct i2c_driver g4fan_driver = {
433 .driver = {
434 .name = "therm_windtunnel",
435 },
436 .attach_adapter = do_attach,
437 .probe = do_probe,
438 .remove = do_remove,
439 .id_table = therm_windtunnel_id,
440};
441
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442
443/************************************************************************/
444/* initialization / cleanup */
445/************************************************************************/
446
447static int
Jeff Mahoney5e655772005-07-06 15:44:41 -0400448therm_of_probe( struct of_device *dev, const struct of_device_id *match )
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449{
450 return i2c_add_driver( &g4fan_driver );
451}
452
453static int
454therm_of_remove( struct of_device *dev )
455{
Jean Delvareb3e82092007-05-01 23:26:32 +0200456 i2c_del_driver( &g4fan_driver );
457 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458}
459
Jeff Mahoney5e655772005-07-06 15:44:41 -0400460static struct of_device_id therm_of_match[] = {{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461 .name = "fan",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 .compatible = "adm1030"
463 }, {}
464};
465
466static 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,
471};
472
473struct apple_thermal_info {
474 u8 id; /* implementation ID */
475 u8 fan_count; /* number of fans */
476 u8 thermostat_count; /* number of thermostats */
477 u8 unused;
478};
479
480static int __init
481g4fan_init( void )
482{
Jeremy Kerr018a3d12006-07-12 15:40:29 +1000483 const struct apple_thermal_info *info;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 struct device_node *np;
485
Daniel Walker1baaeea2008-06-10 09:26:08 +1000486 mutex_init(&x.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487
488 if( !(np=of_find_node_by_name(NULL, "power-mgt")) )
489 return -ENODEV;
Stephen Rothwell01b27262007-04-27 13:41:15 +1000490 info = of_get_property(np, "thermal-info", NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 of_node_put(np);
492
493 if( !info || !machine_is_compatible("PowerMac3,6") )
494 return -ENODEV;
495
496 if( info->id != 3 ) {
497 printk(KERN_ERR "therm_windtunnel: unsupported thermal design %d\n", info->id );
498 return -ENODEV;
499 }
500 if( !(np=of_find_node_by_name(NULL, "fan")) )
501 return -ENODEV;
Benjamin Herrenschmidt0365ba72005-09-22 21:44:06 -0700502 x.of_dev = of_platform_device_create(np, "temperature", NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503 of_node_put( np );
504
505 if( !x.of_dev ) {
506 printk(KERN_ERR "Can't register fan controller!\n");
507 return -ENODEV;
508 }
509
Benjamin Herrenschmidt7eebde72006-11-11 17:24:59 +1100510 of_register_platform_driver( &therm_of_driver );
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 return 0;
512}
513
514static void __exit
515g4fan_exit( void )
516{
Benjamin Herrenschmidt7eebde72006-11-11 17:24:59 +1100517 of_unregister_platform_driver( &therm_of_driver );
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518
519 if( x.of_dev )
520 of_device_unregister( x.of_dev );
521}
522
523module_init(g4fan_init);
524module_exit(g4fan_exit);
525
526MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>");
527MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller");
528MODULE_LICENSE("GPL");