some kmalloc/memset ->kzalloc (tree wide)
[linux-2.6.git] / drivers / macintosh / therm_windtunnel.c
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
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
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_platform.h>
46 #include <asm/macio.h>
47
48 #define LOG_TEMP                0                       /* continously log temperature */
49
50 #define I2C_DRIVERID_G4FAN      0x9001                  /* fixme */
51
52 static int                      do_probe( struct i2c_adapter *adapter, int addr, int kind);
53
54 /* scan 0x48-0x4f (DS1775) and 0x2c-2x2f (ADM1030) */
55 static unsigned short           normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
56                                                  0x4c, 0x4d, 0x4e, 0x4f,
57                                                  0x2c, 0x2d, 0x2e, 0x2f,
58                                                  I2C_CLIENT_END };
59
60 I2C_CLIENT_INSMOD;
61
62 static 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
87 static 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
106 static void
107 print_temp( const char *s, int temp )
108 {
109         printk("%s%d.%d C", s ? s : "", temp>>8, (temp & 255)*10/256 );
110 }
111
112 static ssize_t
113 show_cpu_temperature( struct device *dev, struct device_attribute *attr, char *buf )
114 {
115         return sprintf(buf, "%d.%d\n", x.temp>>8, (x.temp & 255)*10/256 );
116 }
117
118 static ssize_t
119 show_case_temperature( struct device *dev, struct device_attribute *attr, char *buf )
120 {
121         return sprintf(buf, "%d.%d\n", x.casetemp>>8, (x.casetemp & 255)*10/256 );
122 }
123
124 static DEVICE_ATTR(cpu_temperature, S_IRUGO, show_cpu_temperature, NULL );
125 static DEVICE_ATTR(case_temperature, S_IRUGO, show_case_temperature, NULL );
126
127
128
129 /************************************************************************/
130 /*      controller thread                                               */
131 /************************************************************************/
132
133 static int
134 write_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
151 static int
152 read_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
166 static void
167 tune_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
182 static void
183 poll_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
222 static void
223 setup_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
272 static void
273 restore_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
285 static int
286 control_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
313 static int
314 do_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
332 static int
333 do_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
356 static struct i2c_driver g4fan_driver = {  
357         .driver = {
358                 .name   = "therm_windtunnel",
359         },
360         .id             = I2C_DRIVERID_G4FAN,
361         .attach_adapter = do_attach,
362         .detach_client  = do_detach,
363 };
364
365 static int
366 attach_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
386 static int
387 attach_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;
419 out:
420         if( cl != x.thermostat )
421                 kfree( cl );
422         return 0;
423 }
424
425 static int
426 do_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=kzalloc(sizeof(*cl), GFP_KERNEL)) )
435                 return -ENOMEM;
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
453 therm_of_probe( struct of_device *dev, const struct of_device_id *match )
454 {
455         return i2c_add_driver( &g4fan_driver );
456 }
457
458 static int
459 therm_of_remove( struct of_device *dev )
460 {
461         i2c_del_driver( &g4fan_driver );
462         return 0;
463 }
464
465 static struct of_device_id therm_of_match[] = {{
466         .name           = "fan",
467         .compatible     = "adm1030"
468     }, {}
469 };
470
471 static 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
478 struct 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
485 static int __init
486 g4fan_init( void )
487 {
488         const 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 = of_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;
507         x.of_dev = of_platform_device_create(np, "temperature", NULL);
508         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_platform_driver( &therm_of_driver );
516         return 0;
517 }
518
519 static void __exit
520 g4fan_exit( void )
521 {
522         of_unregister_platform_driver( &therm_of_driver );
523
524         if( x.of_dev )
525                 of_device_unregister( x.of_dev );
526 }
527
528 module_init(g4fan_init);
529 module_exit(g4fan_exit);
530
531 MODULE_AUTHOR("Samuel Rydh <samuel@ibrium.se>");
532 MODULE_DESCRIPTION("Apple G4 (windtunnel) fan controller");
533 MODULE_LICENSE("GPL");