[PATCH] openfirmware: generate device table for userspace
[linux-2.6.git] / drivers / macintosh / therm_pm72.c
1 /*
2  * Device driver for the thermostats & fan controller of  the
3  * Apple G5 "PowerMac7,2" desktop machines.
4  *
5  * (c) Copyright IBM Corp. 2003-2004
6  *
7  * Maintained by: Benjamin Herrenschmidt
8  *                <benh@kernel.crashing.org>
9  * 
10  *
11  * The algorithm used is the PID control algorithm, used the same
12  * way the published Darwin code does, using the same values that
13  * are present in the Darwin 7.0 snapshot property lists.
14  *
15  * As far as the CPUs control loops are concerned, I use the
16  * calibration & PID constants provided by the EEPROM,
17  * I do _not_ embed any value from the property lists, as the ones
18  * provided by Darwin 7.0 seem to always have an older version that
19  * what I've seen on the actual computers.
20  * It would be interesting to verify that though. Darwin has a
21  * version code of 1.0.0d11 for all control loops it seems, while
22  * so far, the machines EEPROMs contain a dataset versioned 1.0.0f
23  *
24  * Darwin doesn't provide source to all parts, some missing
25  * bits like the AppleFCU driver or the actual scale of some
26  * of the values returned by sensors had to be "guessed" some
27  * way... or based on what Open Firmware does.
28  *
29  * I didn't yet figure out how to get the slots power consumption
30  * out of the FCU, so that part has not been implemented yet and
31  * the slots fan is set to a fixed 50% PWM, hoping this value is
32  * safe enough ...
33  *
34  * Note: I have observed strange oscillations of the CPU control
35  * loop on a dual G5 here. When idle, the CPU exhaust fan tend to
36  * oscillates slowly (over several minutes) between the minimum
37  * of 300RPMs and approx. 1000 RPMs. I don't know what is causing
38  * this, it could be some incorrect constant or an error in the
39  * way I ported the algorithm, or it could be just normal. I
40  * don't have full understanding on the way Apple tweaked the PID
41  * algorithm for the CPU control, it is definitely not a standard
42  * implementation...
43  *
44  * TODO:  - Check MPU structure version/signature
45  *        - Add things like /sbin/overtemp for non-critical
46  *          overtemp conditions so userland can take some policy
47  *          decisions, like slewing down CPUs
48  *        - Deal with fan and i2c failures in a better way
49  *        - Maybe do a generic PID based on params used for
50  *          U3 and Drives ? Definitely need to factor code a bit
51  *          bettter... also make sensor detection more robust using
52  *          the device-tree to probe for them
53  *        - Figure out how to get the slots consumption and set the
54  *          slots fan accordingly
55  *
56  * History:
57  *
58  *  Nov. 13, 2003 : 0.5
59  *      - First release
60  *
61  *  Nov. 14, 2003 : 0.6
62  *      - Read fan speed from FCU, low level fan routines now deal
63  *        with errors & check fan status, though higher level don't
64  *        do much.
65  *      - Move a bunch of definitions to .h file
66  *
67  *  Nov. 18, 2003 : 0.7
68  *      - Fix build on ppc64 kernel
69  *      - Move back statics definitions to .c file
70  *      - Avoid calling schedule_timeout with a negative number
71  *
72  *  Dec. 18, 2003 : 0.8
73  *      - Fix typo when reading back fan speed on 2 CPU machines
74  *
75  *  Mar. 11, 2004 : 0.9
76  *      - Rework code accessing the ADC chips, make it more robust and
77  *        closer to the chip spec. Also make sure it is configured properly,
78  *        I've seen yet unexplained cases where on startup, I would have stale
79  *        values in the configuration register
80  *      - Switch back to use of target fan speed for PID, thus lowering
81  *        pressure on i2c
82  *
83  *  Oct. 20, 2004 : 1.1
84  *      - Add device-tree lookup for fan IDs, should detect liquid cooling
85  *        pumps when present
86  *      - Enable driver for PowerMac7,3 machines
87  *      - Split the U3/Backside cooling on U3 & U3H versions as Darwin does
88  *      - Add new CPU cooling algorithm for machines with liquid cooling
89  *      - Workaround for some PowerMac7,3 with empty "fan" node in the devtree
90  *      - Fix a signed/unsigned compare issue in some PID loops
91  *
92  *  Mar. 10, 2005 : 1.2
93  *      - Add basic support for Xserve G5
94  *      - Retreive pumps min/max from EEPROM image in device-tree (broken)
95  *      - Use min/max macros here or there
96  *      - Latest darwin updated U3H min fan speed to 20% PWM
97  *
98  */
99
100 #include <linux/config.h>
101 #include <linux/types.h>
102 #include <linux/module.h>
103 #include <linux/errno.h>
104 #include <linux/kernel.h>
105 #include <linux/delay.h>
106 #include <linux/sched.h>
107 #include <linux/i2c.h>
108 #include <linux/slab.h>
109 #include <linux/init.h>
110 #include <linux/spinlock.h>
111 #include <linux/smp_lock.h>
112 #include <linux/wait.h>
113 #include <linux/reboot.h>
114 #include <linux/kmod.h>
115 #include <linux/i2c.h>
116 #include <linux/i2c-dev.h>
117 #include <asm/prom.h>
118 #include <asm/machdep.h>
119 #include <asm/io.h>
120 #include <asm/system.h>
121 #include <asm/sections.h>
122 #include <asm/of_device.h>
123 #include <asm/macio.h>
124
125 #include "therm_pm72.h"
126
127 #define VERSION "1.2b2"
128
129 #undef DEBUG
130
131 #ifdef DEBUG
132 #define DBG(args...)    printk(args)
133 #else
134 #define DBG(args...)    do { } while(0)
135 #endif
136
137
138 /*
139  * Driver statics
140  */
141
142 static struct of_device *               of_dev;
143 static struct i2c_adapter *             u3_0;
144 static struct i2c_adapter *             u3_1;
145 static struct i2c_adapter *             k2;
146 static struct i2c_client *              fcu;
147 static struct cpu_pid_state             cpu_state[2];
148 static struct basckside_pid_params      backside_params;
149 static struct backside_pid_state        backside_state;
150 static struct drives_pid_state          drives_state;
151 static struct dimm_pid_state            dimms_state;
152 static int                              state;
153 static int                              cpu_count;
154 static int                              cpu_pid_type;
155 static pid_t                            ctrl_task;
156 static struct completion                ctrl_complete;
157 static int                              critical_state;
158 static int                              rackmac;
159 static s32                              dimm_output_clamp;
160
161 static DECLARE_MUTEX(driver_lock);
162
163 /*
164  * We have 3 types of CPU PID control. One is "split" old style control
165  * for intake & exhaust fans, the other is "combined" control for both
166  * CPUs that also deals with the pumps when present. To be "compatible"
167  * with OS X at this point, we only use "COMBINED" on the machines that
168  * are identified as having the pumps (though that identification is at
169  * least dodgy). Ultimately, we could probably switch completely to this
170  * algorithm provided we hack it to deal with the UP case
171  */
172 #define CPU_PID_TYPE_SPLIT      0
173 #define CPU_PID_TYPE_COMBINED   1
174 #define CPU_PID_TYPE_RACKMAC    2
175
176 /*
177  * This table describes all fans in the FCU. The "id" and "type" values
178  * are defaults valid for all earlier machines. Newer machines will
179  * eventually override the table content based on the device-tree
180  */
181 struct fcu_fan_table
182 {
183         char*   loc;    /* location code */
184         int     type;   /* 0 = rpm, 1 = pwm, 2 = pump */
185         int     id;     /* id or -1 */
186 };
187
188 #define FCU_FAN_RPM             0
189 #define FCU_FAN_PWM             1
190
191 #define FCU_FAN_ABSENT_ID       -1
192
193 #define FCU_FAN_COUNT           ARRAY_SIZE(fcu_fans)
194
195 struct fcu_fan_table    fcu_fans[] = {
196         [BACKSIDE_FAN_PWM_INDEX] = {
197                 .loc    = "BACKSIDE,SYS CTRLR FAN",
198                 .type   = FCU_FAN_PWM,
199                 .id     = BACKSIDE_FAN_PWM_DEFAULT_ID,
200         },
201         [DRIVES_FAN_RPM_INDEX] = {
202                 .loc    = "DRIVE BAY",
203                 .type   = FCU_FAN_RPM,
204                 .id     = DRIVES_FAN_RPM_DEFAULT_ID,
205         },
206         [SLOTS_FAN_PWM_INDEX] = {
207                 .loc    = "SLOT,PCI FAN",
208                 .type   = FCU_FAN_PWM,
209                 .id     = SLOTS_FAN_PWM_DEFAULT_ID,
210         },
211         [CPUA_INTAKE_FAN_RPM_INDEX] = {
212                 .loc    = "CPU A INTAKE",
213                 .type   = FCU_FAN_RPM,
214                 .id     = CPUA_INTAKE_FAN_RPM_DEFAULT_ID,
215         },
216         [CPUA_EXHAUST_FAN_RPM_INDEX] = {
217                 .loc    = "CPU A EXHAUST",
218                 .type   = FCU_FAN_RPM,
219                 .id     = CPUA_EXHAUST_FAN_RPM_DEFAULT_ID,
220         },
221         [CPUB_INTAKE_FAN_RPM_INDEX] = {
222                 .loc    = "CPU B INTAKE",
223                 .type   = FCU_FAN_RPM,
224                 .id     = CPUB_INTAKE_FAN_RPM_DEFAULT_ID,
225         },
226         [CPUB_EXHAUST_FAN_RPM_INDEX] = {
227                 .loc    = "CPU B EXHAUST",
228                 .type   = FCU_FAN_RPM,
229                 .id     = CPUB_EXHAUST_FAN_RPM_DEFAULT_ID,
230         },
231         /* pumps aren't present by default, have to be looked up in the
232          * device-tree
233          */
234         [CPUA_PUMP_RPM_INDEX] = {
235                 .loc    = "CPU A PUMP",
236                 .type   = FCU_FAN_RPM,          
237                 .id     = FCU_FAN_ABSENT_ID,
238         },
239         [CPUB_PUMP_RPM_INDEX] = {
240                 .loc    = "CPU B PUMP",
241                 .type   = FCU_FAN_RPM,
242                 .id     = FCU_FAN_ABSENT_ID,
243         },
244         /* Xserve fans */
245         [CPU_A1_FAN_RPM_INDEX] = {
246                 .loc    = "CPU A 1",
247                 .type   = FCU_FAN_RPM,
248                 .id     = FCU_FAN_ABSENT_ID,
249         },
250         [CPU_A2_FAN_RPM_INDEX] = {
251                 .loc    = "CPU A 2",
252                 .type   = FCU_FAN_RPM,
253                 .id     = FCU_FAN_ABSENT_ID,
254         },
255         [CPU_A3_FAN_RPM_INDEX] = {
256                 .loc    = "CPU A 3",
257                 .type   = FCU_FAN_RPM,
258                 .id     = FCU_FAN_ABSENT_ID,
259         },
260         [CPU_B1_FAN_RPM_INDEX] = {
261                 .loc    = "CPU B 1",
262                 .type   = FCU_FAN_RPM,
263                 .id     = FCU_FAN_ABSENT_ID,
264         },
265         [CPU_B2_FAN_RPM_INDEX] = {
266                 .loc    = "CPU B 2",
267                 .type   = FCU_FAN_RPM,
268                 .id     = FCU_FAN_ABSENT_ID,
269         },
270         [CPU_B3_FAN_RPM_INDEX] = {
271                 .loc    = "CPU B 3",
272                 .type   = FCU_FAN_RPM,
273                 .id     = FCU_FAN_ABSENT_ID,
274         },
275 };
276
277 /*
278  * i2c_driver structure to attach to the host i2c controller
279  */
280
281 static int therm_pm72_attach(struct i2c_adapter *adapter);
282 static int therm_pm72_detach(struct i2c_adapter *adapter);
283
284 static struct i2c_driver therm_pm72_driver =
285 {
286         .owner          = THIS_MODULE,
287         .name           = "therm_pm72",
288         .flags          = I2C_DF_NOTIFY,
289         .attach_adapter = therm_pm72_attach,
290         .detach_adapter = therm_pm72_detach,
291 };
292
293 /*
294  * Utility function to create an i2c_client structure and
295  * attach it to one of u3 adapters
296  */
297 static struct i2c_client *attach_i2c_chip(int id, const char *name)
298 {
299         struct i2c_client *clt;
300         struct i2c_adapter *adap;
301
302         if (id & 0x200)
303                 adap = k2;
304         else if (id & 0x100)
305                 adap = u3_1;
306         else
307                 adap = u3_0;
308         if (adap == NULL)
309                 return NULL;
310
311         clt = kmalloc(sizeof(struct i2c_client), GFP_KERNEL);
312         if (clt == NULL)
313                 return NULL;
314         memset(clt, 0, sizeof(struct i2c_client));
315
316         clt->addr = (id >> 1) & 0x7f;
317         clt->adapter = adap;
318         clt->driver = &therm_pm72_driver;
319         strncpy(clt->name, name, I2C_NAME_SIZE-1);
320
321         if (i2c_attach_client(clt)) {
322                 printk(KERN_ERR "therm_pm72: Failed to attach to i2c ID 0x%x\n", id);
323                 kfree(clt);
324                 return NULL;
325         }
326         return clt;
327 }
328
329 /*
330  * Utility function to get rid of the i2c_client structure
331  * (will also detach from the adapter hopepfully)
332  */
333 static void detach_i2c_chip(struct i2c_client *clt)
334 {
335         i2c_detach_client(clt);
336         kfree(clt);
337 }
338
339 /*
340  * Here are the i2c chip access wrappers
341  */
342
343 static void initialize_adc(struct cpu_pid_state *state)
344 {
345         int rc;
346         u8 buf[2];
347
348         /* Read ADC the configuration register and cache it. We
349          * also make sure Config2 contains proper values, I've seen
350          * cases where we got stale grabage in there, thus preventing
351          * proper reading of conv. values
352          */
353
354         /* Clear Config2 */
355         buf[0] = 5;
356         buf[1] = 0;
357         i2c_master_send(state->monitor, buf, 2);
358
359         /* Read & cache Config1 */
360         buf[0] = 1;
361         rc = i2c_master_send(state->monitor, buf, 1);
362         if (rc > 0) {
363                 rc = i2c_master_recv(state->monitor, buf, 1);
364                 if (rc > 0) {
365                         state->adc_config = buf[0];
366                         DBG("ADC config reg: %02x\n", state->adc_config);
367                         /* Disable shutdown mode */
368                         state->adc_config &= 0xfe;
369                         buf[0] = 1;
370                         buf[1] = state->adc_config;
371                         rc = i2c_master_send(state->monitor, buf, 2);
372                 }
373         }
374         if (rc <= 0)
375                 printk(KERN_ERR "therm_pm72: Error reading ADC config"
376                        " register !\n");
377 }
378
379 static int read_smon_adc(struct cpu_pid_state *state, int chan)
380 {
381         int rc, data, tries = 0;
382         u8 buf[2];
383
384         for (;;) {
385                 /* Set channel */
386                 buf[0] = 1;
387                 buf[1] = (state->adc_config & 0x1f) | (chan << 5);
388                 rc = i2c_master_send(state->monitor, buf, 2);
389                 if (rc <= 0)
390                         goto error;
391                 /* Wait for convertion */
392                 msleep(1);
393                 /* Switch to data register */
394                 buf[0] = 4;
395                 rc = i2c_master_send(state->monitor, buf, 1);
396                 if (rc <= 0)
397                         goto error;
398                 /* Read result */
399                 rc = i2c_master_recv(state->monitor, buf, 2);
400                 if (rc < 0)
401                         goto error;
402                 data = ((u16)buf[0]) << 8 | (u16)buf[1];
403                 return data >> 6;
404         error:
405                 DBG("Error reading ADC, retrying...\n");
406                 if (++tries > 10) {
407                         printk(KERN_ERR "therm_pm72: Error reading ADC !\n");
408                         return -1;
409                 }
410                 msleep(10);
411         }
412 }
413
414 static int read_lm87_reg(struct i2c_client * chip, int reg)
415 {
416         int rc, tries = 0;
417         u8 buf;
418
419         for (;;) {
420                 /* Set address */
421                 buf = (u8)reg;
422                 rc = i2c_master_send(chip, &buf, 1);
423                 if (rc <= 0)
424                         goto error;
425                 rc = i2c_master_recv(chip, &buf, 1);
426                 if (rc <= 0)
427                         goto error;
428                 return (int)buf;
429         error:
430                 DBG("Error reading LM87, retrying...\n");
431                 if (++tries > 10) {
432                         printk(KERN_ERR "therm_pm72: Error reading LM87 !\n");
433                         return -1;
434                 }
435                 msleep(10);
436         }
437 }
438
439 static int fan_read_reg(int reg, unsigned char *buf, int nb)
440 {
441         int tries, nr, nw;
442
443         buf[0] = reg;
444         tries = 0;
445         for (;;) {
446                 nw = i2c_master_send(fcu, buf, 1);
447                 if (nw > 0 || (nw < 0 && nw != -EIO) || tries >= 100)
448                         break;
449                 msleep(10);
450                 ++tries;
451         }
452         if (nw <= 0) {
453                 printk(KERN_ERR "Failure writing address to FCU: %d", nw);
454                 return -EIO;
455         }
456         tries = 0;
457         for (;;) {
458                 nr = i2c_master_recv(fcu, buf, nb);
459                 if (nr > 0 || (nr < 0 && nr != ENODEV) || tries >= 100)
460                         break;
461                 msleep(10);
462                 ++tries;
463         }
464         if (nr <= 0)
465                 printk(KERN_ERR "Failure reading data from FCU: %d", nw);
466         return nr;
467 }
468
469 static int fan_write_reg(int reg, const unsigned char *ptr, int nb)
470 {
471         int tries, nw;
472         unsigned char buf[16];
473
474         buf[0] = reg;
475         memcpy(buf+1, ptr, nb);
476         ++nb;
477         tries = 0;
478         for (;;) {
479                 nw = i2c_master_send(fcu, buf, nb);
480                 if (nw > 0 || (nw < 0 && nw != EIO) || tries >= 100)
481                         break;
482                 msleep(10);
483                 ++tries;
484         }
485         if (nw < 0)
486                 printk(KERN_ERR "Failure writing to FCU: %d", nw);
487         return nw;
488 }
489
490 static int start_fcu(void)
491 {
492         unsigned char buf = 0xff;
493         int rc;
494
495         rc = fan_write_reg(0xe, &buf, 1);
496         if (rc < 0)
497                 return -EIO;
498         rc = fan_write_reg(0x2e, &buf, 1);
499         if (rc < 0)
500                 return -EIO;
501         return 0;
502 }
503
504 static int set_rpm_fan(int fan_index, int rpm)
505 {
506         unsigned char buf[2];
507         int rc, id;
508
509         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
510                 return -EINVAL;
511         id = fcu_fans[fan_index].id; 
512         if (id == FCU_FAN_ABSENT_ID)
513                 return -EINVAL;
514
515         if (rpm < 300)
516                 rpm = 300;
517         else if (rpm > 8191)
518                 rpm = 8191;
519         buf[0] = rpm >> 5;
520         buf[1] = rpm << 3;
521         rc = fan_write_reg(0x10 + (id * 2), buf, 2);
522         if (rc < 0)
523                 return -EIO;
524         return 0;
525 }
526
527 static int get_rpm_fan(int fan_index, int programmed)
528 {
529         unsigned char failure;
530         unsigned char active;
531         unsigned char buf[2];
532         int rc, id, reg_base;
533
534         if (fcu_fans[fan_index].type != FCU_FAN_RPM)
535                 return -EINVAL;
536         id = fcu_fans[fan_index].id; 
537         if (id == FCU_FAN_ABSENT_ID)
538                 return -EINVAL;
539
540         rc = fan_read_reg(0xb, &failure, 1);
541         if (rc != 1)
542                 return -EIO;
543         if ((failure & (1 << id)) != 0)
544                 return -EFAULT;
545         rc = fan_read_reg(0xd, &active, 1);
546         if (rc != 1)
547                 return -EIO;
548         if ((active & (1 << id)) == 0)
549                 return -ENXIO;
550
551         /* Programmed value or real current speed */
552         reg_base = programmed ? 0x10 : 0x11;
553         rc = fan_read_reg(reg_base + (id * 2), buf, 2);
554         if (rc != 2)
555                 return -EIO;
556
557         return (buf[0] << 5) | buf[1] >> 3;
558 }
559
560 static int set_pwm_fan(int fan_index, int pwm)
561 {
562         unsigned char buf[2];
563         int rc, id;
564
565         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
566                 return -EINVAL;
567         id = fcu_fans[fan_index].id; 
568         if (id == FCU_FAN_ABSENT_ID)
569                 return -EINVAL;
570
571         if (pwm < 10)
572                 pwm = 10;
573         else if (pwm > 100)
574                 pwm = 100;
575         pwm = (pwm * 2559) / 1000;
576         buf[0] = pwm;
577         rc = fan_write_reg(0x30 + (id * 2), buf, 1);
578         if (rc < 0)
579                 return rc;
580         return 0;
581 }
582
583 static int get_pwm_fan(int fan_index)
584 {
585         unsigned char failure;
586         unsigned char active;
587         unsigned char buf[2];
588         int rc, id;
589
590         if (fcu_fans[fan_index].type != FCU_FAN_PWM)
591                 return -EINVAL;
592         id = fcu_fans[fan_index].id; 
593         if (id == FCU_FAN_ABSENT_ID)
594                 return -EINVAL;
595
596         rc = fan_read_reg(0x2b, &failure, 1);
597         if (rc != 1)
598                 return -EIO;
599         if ((failure & (1 << id)) != 0)
600                 return -EFAULT;
601         rc = fan_read_reg(0x2d, &active, 1);
602         if (rc != 1)
603                 return -EIO;
604         if ((active & (1 << id)) == 0)
605                 return -ENXIO;
606
607         /* Programmed value or real current speed */
608         rc = fan_read_reg(0x30 + (id * 2), buf, 1);
609         if (rc != 1)
610                 return -EIO;
611
612         return (buf[0] * 1000) / 2559;
613 }
614
615 /*
616  * Utility routine to read the CPU calibration EEPROM data
617  * from the device-tree
618  */
619 static int read_eeprom(int cpu, struct mpu_data *out)
620 {
621         struct device_node *np;
622         char nodename[64];
623         u8 *data;
624         int len;
625
626         /* prom.c routine for finding a node by path is a bit brain dead
627          * and requires exact @xxx unit numbers. This is a bit ugly but
628          * will work for these machines
629          */
630         sprintf(nodename, "/u3@0,f8000000/i2c@f8001000/cpuid@a%d", cpu ? 2 : 0);
631         np = of_find_node_by_path(nodename);
632         if (np == NULL) {
633                 printk(KERN_ERR "therm_pm72: Failed to retreive cpuid node from device-tree\n");
634                 return -ENODEV;
635         }
636         data = (u8 *)get_property(np, "cpuid", &len);
637         if (data == NULL) {
638                 printk(KERN_ERR "therm_pm72: Failed to retreive cpuid property from device-tree\n");
639                 of_node_put(np);
640                 return -ENODEV;
641         }
642         memcpy(out, data, sizeof(struct mpu_data));
643         of_node_put(np);
644         
645         return 0;
646 }
647
648 static void fetch_cpu_pumps_minmax(void)
649 {
650         struct cpu_pid_state *state0 = &cpu_state[0];
651         struct cpu_pid_state *state1 = &cpu_state[1];
652         u16 pump_min = 0, pump_max = 0xffff;
653         u16 tmp[4];
654
655         /* Try to fetch pumps min/max infos from eeprom */
656
657         memcpy(&tmp, &state0->mpu.processor_part_num, 8);
658         if (tmp[0] != 0xffff && tmp[1] != 0xffff) {
659                 pump_min = max(pump_min, tmp[0]);
660                 pump_max = min(pump_max, tmp[1]);
661         }
662         if (tmp[2] != 0xffff && tmp[3] != 0xffff) {
663                 pump_min = max(pump_min, tmp[2]);
664                 pump_max = min(pump_max, tmp[3]);
665         }
666
667         /* Double check the values, this _IS_ needed as the EEPROM on
668          * some dual 2.5Ghz G5s seem, at least, to have both min & max
669          * same to the same value ... (grrrr)
670          */
671         if (pump_min == pump_max || pump_min == 0 || pump_max == 0xffff) {
672                 pump_min = CPU_PUMP_OUTPUT_MIN;
673                 pump_max = CPU_PUMP_OUTPUT_MAX;
674         }
675
676         state0->pump_min = state1->pump_min = pump_min;
677         state0->pump_max = state1->pump_max = pump_max;
678 }
679
680 /* 
681  * Now, unfortunately, sysfs doesn't give us a nice void * we could
682  * pass around to the attribute functions, so we don't really have
683  * choice but implement a bunch of them...
684  *
685  * That sucks a bit, we take the lock because FIX32TOPRINT evaluates
686  * the input twice... I accept patches :)
687  */
688 #define BUILD_SHOW_FUNC_FIX(name, data)                         \
689 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
690 {                                                               \
691         ssize_t r;                                              \
692         down(&driver_lock);                                     \
693         r = sprintf(buf, "%d.%03d", FIX32TOPRINT(data));        \
694         up(&driver_lock);                                       \
695         return r;                                               \
696 }
697 #define BUILD_SHOW_FUNC_INT(name, data)                         \
698 static ssize_t show_##name(struct device *dev, struct device_attribute *attr, char *buf)        \
699 {                                                               \
700         return sprintf(buf, "%d", data);                        \
701 }
702
703 BUILD_SHOW_FUNC_FIX(cpu0_temperature, cpu_state[0].last_temp)
704 BUILD_SHOW_FUNC_FIX(cpu0_voltage, cpu_state[0].voltage)
705 BUILD_SHOW_FUNC_FIX(cpu0_current, cpu_state[0].current_a)
706 BUILD_SHOW_FUNC_INT(cpu0_exhaust_fan_rpm, cpu_state[0].rpm)
707 BUILD_SHOW_FUNC_INT(cpu0_intake_fan_rpm, cpu_state[0].intake_rpm)
708
709 BUILD_SHOW_FUNC_FIX(cpu1_temperature, cpu_state[1].last_temp)
710 BUILD_SHOW_FUNC_FIX(cpu1_voltage, cpu_state[1].voltage)
711 BUILD_SHOW_FUNC_FIX(cpu1_current, cpu_state[1].current_a)
712 BUILD_SHOW_FUNC_INT(cpu1_exhaust_fan_rpm, cpu_state[1].rpm)
713 BUILD_SHOW_FUNC_INT(cpu1_intake_fan_rpm, cpu_state[1].intake_rpm)
714
715 BUILD_SHOW_FUNC_FIX(backside_temperature, backside_state.last_temp)
716 BUILD_SHOW_FUNC_INT(backside_fan_pwm, backside_state.pwm)
717
718 BUILD_SHOW_FUNC_FIX(drives_temperature, drives_state.last_temp)
719 BUILD_SHOW_FUNC_INT(drives_fan_rpm, drives_state.rpm)
720
721 BUILD_SHOW_FUNC_FIX(dimms_temperature, dimms_state.last_temp)
722
723 static DEVICE_ATTR(cpu0_temperature,S_IRUGO,show_cpu0_temperature,NULL);
724 static DEVICE_ATTR(cpu0_voltage,S_IRUGO,show_cpu0_voltage,NULL);
725 static DEVICE_ATTR(cpu0_current,S_IRUGO,show_cpu0_current,NULL);
726 static DEVICE_ATTR(cpu0_exhaust_fan_rpm,S_IRUGO,show_cpu0_exhaust_fan_rpm,NULL);
727 static DEVICE_ATTR(cpu0_intake_fan_rpm,S_IRUGO,show_cpu0_intake_fan_rpm,NULL);
728
729 static DEVICE_ATTR(cpu1_temperature,S_IRUGO,show_cpu1_temperature,NULL);
730 static DEVICE_ATTR(cpu1_voltage,S_IRUGO,show_cpu1_voltage,NULL);
731 static DEVICE_ATTR(cpu1_current,S_IRUGO,show_cpu1_current,NULL);
732 static DEVICE_ATTR(cpu1_exhaust_fan_rpm,S_IRUGO,show_cpu1_exhaust_fan_rpm,NULL);
733 static DEVICE_ATTR(cpu1_intake_fan_rpm,S_IRUGO,show_cpu1_intake_fan_rpm,NULL);
734
735 static DEVICE_ATTR(backside_temperature,S_IRUGO,show_backside_temperature,NULL);
736 static DEVICE_ATTR(backside_fan_pwm,S_IRUGO,show_backside_fan_pwm,NULL);
737
738 static DEVICE_ATTR(drives_temperature,S_IRUGO,show_drives_temperature,NULL);
739 static DEVICE_ATTR(drives_fan_rpm,S_IRUGO,show_drives_fan_rpm,NULL);
740
741 static DEVICE_ATTR(dimms_temperature,S_IRUGO,show_dimms_temperature,NULL);
742
743 /*
744  * CPUs fans control loop
745  */
746
747 static int do_read_one_cpu_values(struct cpu_pid_state *state, s32 *temp, s32 *power)
748 {
749         s32 ltemp, volts, amps;
750         int index, rc = 0;
751
752         /* Default (in case of error) */
753         *temp = state->cur_temp;
754         *power = state->cur_power;
755
756         if (cpu_pid_type == CPU_PID_TYPE_RACKMAC)
757                 index = (state->index == 0) ?
758                         CPU_A1_FAN_RPM_INDEX : CPU_B1_FAN_RPM_INDEX;
759         else
760                 index = (state->index == 0) ?
761                         CPUA_EXHAUST_FAN_RPM_INDEX : CPUB_EXHAUST_FAN_RPM_INDEX;
762
763         /* Read current fan status */
764         rc = get_rpm_fan(index, !RPM_PID_USE_ACTUAL_SPEED);
765         if (rc < 0) {
766                 /* XXX What do we do now ? Nothing for now, keep old value, but
767                  * return error upstream
768                  */
769                 DBG("  cpu %d, fan reading error !\n", state->index);
770         } else {
771                 state->rpm = rc;
772                 DBG("  cpu %d, exhaust RPM: %d\n", state->index, state->rpm);
773         }
774
775         /* Get some sensor readings and scale it */
776         ltemp = read_smon_adc(state, 1);
777         if (ltemp == -1) {
778                 /* XXX What do we do now ? */
779                 state->overtemp++;
780                 if (rc == 0)
781                         rc = -EIO;
782                 DBG("  cpu %d, temp reading error !\n", state->index);
783         } else {
784                 /* Fixup temperature according to diode calibration
785                  */
786                 DBG("  cpu %d, temp raw: %04x, m_diode: %04x, b_diode: %04x\n",
787                     state->index,
788                     ltemp, state->mpu.mdiode, state->mpu.bdiode);
789                 *temp = ((s32)ltemp * (s32)state->mpu.mdiode + ((s32)state->mpu.bdiode << 12)) >> 2;
790                 state->last_temp = *temp;
791                 DBG("  temp: %d.%03d\n", FIX32TOPRINT((*temp)));
792         }
793
794         /*
795          * Read voltage & current and calculate power
796          */
797         volts = read_smon_adc(state, 3);
798         amps = read_smon_adc(state, 4);
799
800         /* Scale voltage and current raw sensor values according to fixed scales
801          * obtained in Darwin and calculate power from I and V
802          */
803         volts *= ADC_CPU_VOLTAGE_SCALE;
804         amps *= ADC_CPU_CURRENT_SCALE;
805         *power = (((u64)volts) * ((u64)amps)) >> 16;
806         state->voltage = volts;
807         state->current_a = amps;
808         state->last_power = *power;
809
810         DBG("  cpu %d, current: %d.%03d, voltage: %d.%03d, power: %d.%03d W\n",
811             state->index, FIX32TOPRINT(state->current_a),
812             FIX32TOPRINT(state->voltage), FIX32TOPRINT(*power));
813
814         return 0;
815 }
816
817 static void do_cpu_pid(struct cpu_pid_state *state, s32 temp, s32 power)
818 {
819         s32 power_target, integral, derivative, proportional, adj_in_target, sval;
820         s64 integ_p, deriv_p, prop_p, sum; 
821         int i;
822
823         /* Calculate power target value (could be done once for all)
824          * and convert to a 16.16 fp number
825          */
826         power_target = ((u32)(state->mpu.pmaxh - state->mpu.padjmax)) << 16;
827         DBG("  power target: %d.%03d, error: %d.%03d\n",
828             FIX32TOPRINT(power_target), FIX32TOPRINT(power_target - power));
829
830         /* Store temperature and power in history array */
831         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
832         state->temp_history[state->cur_temp] = temp;
833         state->cur_power = (state->cur_power + 1) % state->count_power;
834         state->power_history[state->cur_power] = power;
835         state->error_history[state->cur_power] = power_target - power;
836         
837         /* If first loop, fill the history table */
838         if (state->first) {
839                 for (i = 0; i < (state->count_power - 1); i++) {
840                         state->cur_power = (state->cur_power + 1) % state->count_power;
841                         state->power_history[state->cur_power] = power;
842                         state->error_history[state->cur_power] = power_target - power;
843                 }
844                 for (i = 0; i < (CPU_TEMP_HISTORY_SIZE - 1); i++) {
845                         state->cur_temp = (state->cur_temp + 1) % CPU_TEMP_HISTORY_SIZE;
846                         state->temp_history[state->cur_temp] = temp;                    
847                 }
848                 state->first = 0;
849         }
850
851         /* Calculate the integral term normally based on the "power" values */
852         sum = 0;
853         integral = 0;
854         for (i = 0; i < state->count_power; i++)
855                 integral += state->error_history[i];
856         integral *= CPU_PID_INTERVAL;
857         DBG("  integral: %08x\n", integral);
858
859         /* Calculate the adjusted input (sense value).
860          *   G_r is 12.20
861          *   integ is 16.16
862          *   so the result is 28.36
863          *
864          * input target is mpu.ttarget, input max is mpu.tmax
865          */
866         integ_p = ((s64)state->mpu.pid_gr) * (s64)integral;
867         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
868         sval = (state->mpu.tmax << 16) - ((integ_p >> 20) & 0xffffffff);
869         adj_in_target = (state->mpu.ttarget << 16);
870         if (adj_in_target > sval)
871                 adj_in_target = sval;
872         DBG("   adj_in_target: %d.%03d, ttarget: %d\n", FIX32TOPRINT(adj_in_target),
873             state->mpu.ttarget);
874
875         /* Calculate the derivative term */
876         derivative = state->temp_history[state->cur_temp] -
877                 state->temp_history[(state->cur_temp + CPU_TEMP_HISTORY_SIZE - 1)
878                                     % CPU_TEMP_HISTORY_SIZE];
879         derivative /= CPU_PID_INTERVAL;
880         deriv_p = ((s64)state->mpu.pid_gd) * (s64)derivative;
881         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
882         sum += deriv_p;
883
884         /* Calculate the proportional term */
885         proportional = temp - adj_in_target;
886         prop_p = ((s64)state->mpu.pid_gp) * (s64)proportional;
887         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
888         sum += prop_p;
889
890         /* Scale sum */
891         sum >>= 36;
892
893         DBG("   sum: %d\n", (int)sum);
894         state->rpm += (s32)sum;
895 }
896
897 static void do_monitor_cpu_combined(void)
898 {
899         struct cpu_pid_state *state0 = &cpu_state[0];
900         struct cpu_pid_state *state1 = &cpu_state[1];
901         s32 temp0, power0, temp1, power1;
902         s32 temp_combi, power_combi;
903         int rc, intake, pump;
904
905         rc = do_read_one_cpu_values(state0, &temp0, &power0);
906         if (rc < 0) {
907                 /* XXX What do we do now ? */
908         }
909         state1->overtemp = 0;
910         rc = do_read_one_cpu_values(state1, &temp1, &power1);
911         if (rc < 0) {
912                 /* XXX What do we do now ? */
913         }
914         if (state1->overtemp)
915                 state0->overtemp++;
916
917         temp_combi = max(temp0, temp1);
918         power_combi = max(power0, power1);
919
920         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
921          * full blown immediately and try to trigger a shutdown
922          */
923         if (temp_combi >= ((state0->mpu.tmax + 8) << 16)) {
924                 printk(KERN_WARNING "Warning ! Temperature way above maximum (%d) !\n",
925                        temp_combi >> 16);
926                 state0->overtemp = CPU_MAX_OVERTEMP;
927         } else if (temp_combi > (state0->mpu.tmax << 16))
928                 state0->overtemp++;
929         else
930                 state0->overtemp = 0;
931         if (state0->overtemp >= CPU_MAX_OVERTEMP)
932                 critical_state = 1;
933         if (state0->overtemp > 0) {
934                 state0->rpm = state0->mpu.rmaxn_exhaust_fan;
935                 state0->intake_rpm = intake = state0->mpu.rmaxn_intake_fan;
936                 pump = state0->pump_min;
937                 goto do_set_fans;
938         }
939
940         /* Do the PID */
941         do_cpu_pid(state0, temp_combi, power_combi);
942
943         /* Range check */
944         state0->rpm = max(state0->rpm, (int)state0->mpu.rminn_exhaust_fan);
945         state0->rpm = min(state0->rpm, (int)state0->mpu.rmaxn_exhaust_fan);
946
947         /* Calculate intake fan speed */
948         intake = (state0->rpm * CPU_INTAKE_SCALE) >> 16;
949         intake = max(intake, (int)state0->mpu.rminn_intake_fan);
950         intake = min(intake, (int)state0->mpu.rmaxn_intake_fan);
951         state0->intake_rpm = intake;
952
953         /* Calculate pump speed */
954         pump = (state0->rpm * state0->pump_max) /
955                 state0->mpu.rmaxn_exhaust_fan;
956         pump = min(pump, state0->pump_max);
957         pump = max(pump, state0->pump_min);
958         
959  do_set_fans:
960         /* We copy values from state 0 to state 1 for /sysfs */
961         state1->rpm = state0->rpm;
962         state1->intake_rpm = state0->intake_rpm;
963
964         DBG("** CPU %d RPM: %d Ex, %d, Pump: %d, In, overtemp: %d\n",
965             state1->index, (int)state1->rpm, intake, pump, state1->overtemp);
966
967         /* We should check for errors, shouldn't we ? But then, what
968          * do we do once the error occurs ? For FCU notified fan
969          * failures (-EFAULT) we probably want to notify userland
970          * some way...
971          */
972         set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
973         set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state0->rpm);
974         set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
975         set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state0->rpm);
976
977         if (fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
978                 set_rpm_fan(CPUA_PUMP_RPM_INDEX, pump);
979         if (fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID)
980                 set_rpm_fan(CPUB_PUMP_RPM_INDEX, pump);
981 }
982
983 static void do_monitor_cpu_split(struct cpu_pid_state *state)
984 {
985         s32 temp, power;
986         int rc, intake;
987
988         /* Read current fan status */
989         rc = do_read_one_cpu_values(state, &temp, &power);
990         if (rc < 0) {
991                 /* XXX What do we do now ? */
992         }
993
994         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
995          * full blown immediately and try to trigger a shutdown
996          */
997         if (temp >= ((state->mpu.tmax + 8) << 16)) {
998                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
999                        " (%d) !\n",
1000                        state->index, temp >> 16);
1001                 state->overtemp = CPU_MAX_OVERTEMP;
1002         } else if (temp > (state->mpu.tmax << 16))
1003                 state->overtemp++;
1004         else
1005                 state->overtemp = 0;
1006         if (state->overtemp >= CPU_MAX_OVERTEMP)
1007                 critical_state = 1;
1008         if (state->overtemp > 0) {
1009                 state->rpm = state->mpu.rmaxn_exhaust_fan;
1010                 state->intake_rpm = intake = state->mpu.rmaxn_intake_fan;
1011                 goto do_set_fans;
1012         }
1013
1014         /* Do the PID */
1015         do_cpu_pid(state, temp, power);
1016
1017         /* Range check */
1018         state->rpm = max(state->rpm, (int)state->mpu.rminn_exhaust_fan);
1019         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_exhaust_fan);
1020
1021         /* Calculate intake fan */
1022         intake = (state->rpm * CPU_INTAKE_SCALE) >> 16;
1023         intake = max(intake, (int)state->mpu.rminn_intake_fan);
1024         intake = min(intake, (int)state->mpu.rmaxn_intake_fan);
1025         state->intake_rpm = intake;
1026
1027  do_set_fans:
1028         DBG("** CPU %d RPM: %d Ex, %d In, overtemp: %d\n",
1029             state->index, (int)state->rpm, intake, state->overtemp);
1030
1031         /* We should check for errors, shouldn't we ? But then, what
1032          * do we do once the error occurs ? For FCU notified fan
1033          * failures (-EFAULT) we probably want to notify userland
1034          * some way...
1035          */
1036         if (state->index == 0) {
1037                 set_rpm_fan(CPUA_INTAKE_FAN_RPM_INDEX, intake);
1038                 set_rpm_fan(CPUA_EXHAUST_FAN_RPM_INDEX, state->rpm);
1039         } else {
1040                 set_rpm_fan(CPUB_INTAKE_FAN_RPM_INDEX, intake);
1041                 set_rpm_fan(CPUB_EXHAUST_FAN_RPM_INDEX, state->rpm);
1042         }
1043 }
1044
1045 static void do_monitor_cpu_rack(struct cpu_pid_state *state)
1046 {
1047         s32 temp, power, fan_min;
1048         int rc;
1049
1050         /* Read current fan status */
1051         rc = do_read_one_cpu_values(state, &temp, &power);
1052         if (rc < 0) {
1053                 /* XXX What do we do now ? */
1054         }
1055
1056         /* Check tmax, increment overtemp if we are there. At tmax+8, we go
1057          * full blown immediately and try to trigger a shutdown
1058          */
1059         if (temp >= ((state->mpu.tmax + 8) << 16)) {
1060                 printk(KERN_WARNING "Warning ! CPU %d temperature way above maximum"
1061                        " (%d) !\n",
1062                        state->index, temp >> 16);
1063                 state->overtemp = CPU_MAX_OVERTEMP;
1064         } else if (temp > (state->mpu.tmax << 16))
1065                 state->overtemp++;
1066         else
1067                 state->overtemp = 0;
1068         if (state->overtemp >= CPU_MAX_OVERTEMP)
1069                 critical_state = 1;
1070         if (state->overtemp > 0) {
1071                 state->rpm = state->intake_rpm = state->mpu.rmaxn_intake_fan;
1072                 goto do_set_fans;
1073         }
1074
1075         /* Do the PID */
1076         do_cpu_pid(state, temp, power);
1077
1078         /* Check clamp from dimms */
1079         fan_min = dimm_output_clamp;
1080         fan_min = max(fan_min, (int)state->mpu.rminn_intake_fan);
1081
1082         state->rpm = max(state->rpm, (int)fan_min);
1083         state->rpm = min(state->rpm, (int)state->mpu.rmaxn_intake_fan);
1084         state->intake_rpm = state->rpm;
1085
1086  do_set_fans:
1087         DBG("** CPU %d RPM: %d overtemp: %d\n",
1088             state->index, (int)state->rpm, state->overtemp);
1089
1090         /* We should check for errors, shouldn't we ? But then, what
1091          * do we do once the error occurs ? For FCU notified fan
1092          * failures (-EFAULT) we probably want to notify userland
1093          * some way...
1094          */
1095         if (state->index == 0) {
1096                 set_rpm_fan(CPU_A1_FAN_RPM_INDEX, state->rpm);
1097                 set_rpm_fan(CPU_A2_FAN_RPM_INDEX, state->rpm);
1098                 set_rpm_fan(CPU_A3_FAN_RPM_INDEX, state->rpm);
1099         } else {
1100                 set_rpm_fan(CPU_B1_FAN_RPM_INDEX, state->rpm);
1101                 set_rpm_fan(CPU_B2_FAN_RPM_INDEX, state->rpm);
1102                 set_rpm_fan(CPU_B3_FAN_RPM_INDEX, state->rpm);
1103         }
1104 }
1105
1106 /*
1107  * Initialize the state structure for one CPU control loop
1108  */
1109 static int init_cpu_state(struct cpu_pid_state *state, int index)
1110 {
1111         state->index = index;
1112         state->first = 1;
1113         state->rpm = (cpu_pid_type == CPU_PID_TYPE_RACKMAC) ? 4000 : 1000;
1114         state->overtemp = 0;
1115         state->adc_config = 0x00;
1116
1117
1118         if (index == 0)
1119                 state->monitor = attach_i2c_chip(SUPPLY_MONITOR_ID, "CPU0_monitor");
1120         else if (index == 1)
1121                 state->monitor = attach_i2c_chip(SUPPLY_MONITORB_ID, "CPU1_monitor");
1122         if (state->monitor == NULL)
1123                 goto fail;
1124
1125         if (read_eeprom(index, &state->mpu))
1126                 goto fail;
1127
1128         state->count_power = state->mpu.tguardband;
1129         if (state->count_power > CPU_POWER_HISTORY_SIZE) {
1130                 printk(KERN_WARNING "Warning ! too many power history slots\n");
1131                 state->count_power = CPU_POWER_HISTORY_SIZE;
1132         }
1133         DBG("CPU %d Using %d power history entries\n", index, state->count_power);
1134
1135         if (index == 0) {
1136                 device_create_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1137                 device_create_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1138                 device_create_file(&of_dev->dev, &dev_attr_cpu0_current);
1139                 device_create_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1140                 device_create_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1141         } else {
1142                 device_create_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1143                 device_create_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1144                 device_create_file(&of_dev->dev, &dev_attr_cpu1_current);
1145                 device_create_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1146                 device_create_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1147         }
1148
1149         return 0;
1150  fail:
1151         if (state->monitor)
1152                 detach_i2c_chip(state->monitor);
1153         state->monitor = NULL;
1154         
1155         return -ENODEV;
1156 }
1157
1158 /*
1159  * Dispose of the state data for one CPU control loop
1160  */
1161 static void dispose_cpu_state(struct cpu_pid_state *state)
1162 {
1163         if (state->monitor == NULL)
1164                 return;
1165
1166         if (state->index == 0) {
1167                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_temperature);
1168                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_voltage);
1169                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_current);
1170                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_exhaust_fan_rpm);
1171                 device_remove_file(&of_dev->dev, &dev_attr_cpu0_intake_fan_rpm);
1172         } else {
1173                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_temperature);
1174                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_voltage);
1175                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_current);
1176                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_exhaust_fan_rpm);
1177                 device_remove_file(&of_dev->dev, &dev_attr_cpu1_intake_fan_rpm);
1178         }
1179
1180         detach_i2c_chip(state->monitor);
1181         state->monitor = NULL;
1182 }
1183
1184 /*
1185  * Motherboard backside & U3 heatsink fan control loop
1186  */
1187 static void do_monitor_backside(struct backside_pid_state *state)
1188 {
1189         s32 temp, integral, derivative, fan_min;
1190         s64 integ_p, deriv_p, prop_p, sum; 
1191         int i, rc;
1192
1193         if (--state->ticks != 0)
1194                 return;
1195         state->ticks = backside_params.interval;
1196
1197         DBG("backside:\n");
1198
1199         /* Check fan status */
1200         rc = get_pwm_fan(BACKSIDE_FAN_PWM_INDEX);
1201         if (rc < 0) {
1202                 printk(KERN_WARNING "Error %d reading backside fan !\n", rc);
1203                 /* XXX What do we do now ? */
1204         } else
1205                 state->pwm = rc;
1206         DBG("  current pwm: %d\n", state->pwm);
1207
1208         /* Get some sensor readings */
1209         temp = i2c_smbus_read_byte_data(state->monitor, MAX6690_EXT_TEMP) << 16;
1210         state->last_temp = temp;
1211         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1212             FIX32TOPRINT(backside_params.input_target));
1213
1214         /* Store temperature and error in history array */
1215         state->cur_sample = (state->cur_sample + 1) % BACKSIDE_PID_HISTORY_SIZE;
1216         state->sample_history[state->cur_sample] = temp;
1217         state->error_history[state->cur_sample] = temp - backside_params.input_target;
1218         
1219         /* If first loop, fill the history table */
1220         if (state->first) {
1221                 for (i = 0; i < (BACKSIDE_PID_HISTORY_SIZE - 1); i++) {
1222                         state->cur_sample = (state->cur_sample + 1) %
1223                                 BACKSIDE_PID_HISTORY_SIZE;
1224                         state->sample_history[state->cur_sample] = temp;
1225                         state->error_history[state->cur_sample] =
1226                                 temp - backside_params.input_target;
1227                 }
1228                 state->first = 0;
1229         }
1230
1231         /* Calculate the integral term */
1232         sum = 0;
1233         integral = 0;
1234         for (i = 0; i < BACKSIDE_PID_HISTORY_SIZE; i++)
1235                 integral += state->error_history[i];
1236         integral *= backside_params.interval;
1237         DBG("  integral: %08x\n", integral);
1238         integ_p = ((s64)backside_params.G_r) * (s64)integral;
1239         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1240         sum += integ_p;
1241
1242         /* Calculate the derivative term */
1243         derivative = state->error_history[state->cur_sample] -
1244                 state->error_history[(state->cur_sample + BACKSIDE_PID_HISTORY_SIZE - 1)
1245                                     % BACKSIDE_PID_HISTORY_SIZE];
1246         derivative /= backside_params.interval;
1247         deriv_p = ((s64)backside_params.G_d) * (s64)derivative;
1248         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1249         sum += deriv_p;
1250
1251         /* Calculate the proportional term */
1252         prop_p = ((s64)backside_params.G_p) * (s64)(state->error_history[state->cur_sample]);
1253         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1254         sum += prop_p;
1255
1256         /* Scale sum */
1257         sum >>= 36;
1258
1259         DBG("   sum: %d\n", (int)sum);
1260         if (backside_params.additive)
1261                 state->pwm += (s32)sum;
1262         else
1263                 state->pwm = sum;
1264
1265         /* Check for clamp */
1266         fan_min = (dimm_output_clamp * 100) / 14000;
1267         fan_min = max(fan_min, backside_params.output_min);
1268
1269         state->pwm = max(state->pwm, fan_min);
1270         state->pwm = min(state->pwm, backside_params.output_max);
1271
1272         DBG("** BACKSIDE PWM: %d\n", (int)state->pwm);
1273         set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, state->pwm);
1274 }
1275
1276 /*
1277  * Initialize the state structure for the backside fan control loop
1278  */
1279 static int init_backside_state(struct backside_pid_state *state)
1280 {
1281         struct device_node *u3;
1282         int u3h = 1; /* conservative by default */
1283
1284         /*
1285          * There are different PID params for machines with U3 and machines
1286          * with U3H, pick the right ones now
1287          */
1288         u3 = of_find_node_by_path("/u3@0,f8000000");
1289         if (u3 != NULL) {
1290                 u32 *vers = (u32 *)get_property(u3, "device-rev", NULL);
1291                 if (vers)
1292                         if (((*vers) & 0x3f) < 0x34)
1293                                 u3h = 0;
1294                 of_node_put(u3);
1295         }
1296
1297         if (rackmac) {
1298                 backside_params.G_d = BACKSIDE_PID_RACK_G_d;
1299                 backside_params.input_target = BACKSIDE_PID_RACK_INPUT_TARGET;
1300                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1301                 backside_params.interval = BACKSIDE_PID_RACK_INTERVAL;
1302                 backside_params.G_p = BACKSIDE_PID_RACK_G_p;
1303                 backside_params.G_r = BACKSIDE_PID_G_r;
1304                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1305                 backside_params.additive = 0;
1306         } else if (u3h) {
1307                 backside_params.G_d = BACKSIDE_PID_U3H_G_d;
1308                 backside_params.input_target = BACKSIDE_PID_U3H_INPUT_TARGET;
1309                 backside_params.output_min = BACKSIDE_PID_U3H_OUTPUT_MIN;
1310                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1311                 backside_params.G_p = BACKSIDE_PID_G_p;
1312                 backside_params.G_r = BACKSIDE_PID_G_r;
1313                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1314                 backside_params.additive = 1;
1315         } else {
1316                 backside_params.G_d = BACKSIDE_PID_U3_G_d;
1317                 backside_params.input_target = BACKSIDE_PID_U3_INPUT_TARGET;
1318                 backside_params.output_min = BACKSIDE_PID_U3_OUTPUT_MIN;
1319                 backside_params.interval = BACKSIDE_PID_INTERVAL;
1320                 backside_params.G_p = BACKSIDE_PID_G_p;
1321                 backside_params.G_r = BACKSIDE_PID_G_r;
1322                 backside_params.output_max = BACKSIDE_PID_OUTPUT_MAX;
1323                 backside_params.additive = 1;
1324         }
1325
1326         state->ticks = 1;
1327         state->first = 1;
1328         state->pwm = 50;
1329
1330         state->monitor = attach_i2c_chip(BACKSIDE_MAX_ID, "backside_temp");
1331         if (state->monitor == NULL)
1332                 return -ENODEV;
1333
1334         device_create_file(&of_dev->dev, &dev_attr_backside_temperature);
1335         device_create_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1336
1337         return 0;
1338 }
1339
1340 /*
1341  * Dispose of the state data for the backside control loop
1342  */
1343 static void dispose_backside_state(struct backside_pid_state *state)
1344 {
1345         if (state->monitor == NULL)
1346                 return;
1347
1348         device_remove_file(&of_dev->dev, &dev_attr_backside_temperature);
1349         device_remove_file(&of_dev->dev, &dev_attr_backside_fan_pwm);
1350
1351         detach_i2c_chip(state->monitor);
1352         state->monitor = NULL;
1353 }
1354  
1355 /*
1356  * Drives bay fan control loop
1357  */
1358 static void do_monitor_drives(struct drives_pid_state *state)
1359 {
1360         s32 temp, integral, derivative;
1361         s64 integ_p, deriv_p, prop_p, sum; 
1362         int i, rc;
1363
1364         if (--state->ticks != 0)
1365                 return;
1366         state->ticks = DRIVES_PID_INTERVAL;
1367
1368         DBG("drives:\n");
1369
1370         /* Check fan status */
1371         rc = get_rpm_fan(DRIVES_FAN_RPM_INDEX, !RPM_PID_USE_ACTUAL_SPEED);
1372         if (rc < 0) {
1373                 printk(KERN_WARNING "Error %d reading drives fan !\n", rc);
1374                 /* XXX What do we do now ? */
1375         } else
1376                 state->rpm = rc;
1377         DBG("  current rpm: %d\n", state->rpm);
1378
1379         /* Get some sensor readings */
1380         temp = le16_to_cpu(i2c_smbus_read_word_data(state->monitor, DS1775_TEMP)) << 8;
1381         state->last_temp = temp;
1382         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1383             FIX32TOPRINT(DRIVES_PID_INPUT_TARGET));
1384
1385         /* Store temperature and error in history array */
1386         state->cur_sample = (state->cur_sample + 1) % DRIVES_PID_HISTORY_SIZE;
1387         state->sample_history[state->cur_sample] = temp;
1388         state->error_history[state->cur_sample] = temp - DRIVES_PID_INPUT_TARGET;
1389         
1390         /* If first loop, fill the history table */
1391         if (state->first) {
1392                 for (i = 0; i < (DRIVES_PID_HISTORY_SIZE - 1); i++) {
1393                         state->cur_sample = (state->cur_sample + 1) %
1394                                 DRIVES_PID_HISTORY_SIZE;
1395                         state->sample_history[state->cur_sample] = temp;
1396                         state->error_history[state->cur_sample] =
1397                                 temp - DRIVES_PID_INPUT_TARGET;
1398                 }
1399                 state->first = 0;
1400         }
1401
1402         /* Calculate the integral term */
1403         sum = 0;
1404         integral = 0;
1405         for (i = 0; i < DRIVES_PID_HISTORY_SIZE; i++)
1406                 integral += state->error_history[i];
1407         integral *= DRIVES_PID_INTERVAL;
1408         DBG("  integral: %08x\n", integral);
1409         integ_p = ((s64)DRIVES_PID_G_r) * (s64)integral;
1410         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1411         sum += integ_p;
1412
1413         /* Calculate the derivative term */
1414         derivative = state->error_history[state->cur_sample] -
1415                 state->error_history[(state->cur_sample + DRIVES_PID_HISTORY_SIZE - 1)
1416                                     % DRIVES_PID_HISTORY_SIZE];
1417         derivative /= DRIVES_PID_INTERVAL;
1418         deriv_p = ((s64)DRIVES_PID_G_d) * (s64)derivative;
1419         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1420         sum += deriv_p;
1421
1422         /* Calculate the proportional term */
1423         prop_p = ((s64)DRIVES_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1424         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1425         sum += prop_p;
1426
1427         /* Scale sum */
1428         sum >>= 36;
1429
1430         DBG("   sum: %d\n", (int)sum);
1431         state->rpm += (s32)sum;
1432
1433         state->rpm = max(state->rpm, DRIVES_PID_OUTPUT_MIN);
1434         state->rpm = min(state->rpm, DRIVES_PID_OUTPUT_MAX);
1435
1436         DBG("** DRIVES RPM: %d\n", (int)state->rpm);
1437         set_rpm_fan(DRIVES_FAN_RPM_INDEX, state->rpm);
1438 }
1439
1440 /*
1441  * Initialize the state structure for the drives bay fan control loop
1442  */
1443 static int init_drives_state(struct drives_pid_state *state)
1444 {
1445         state->ticks = 1;
1446         state->first = 1;
1447         state->rpm = 1000;
1448
1449         state->monitor = attach_i2c_chip(DRIVES_DALLAS_ID, "drives_temp");
1450         if (state->monitor == NULL)
1451                 return -ENODEV;
1452
1453         device_create_file(&of_dev->dev, &dev_attr_drives_temperature);
1454         device_create_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1455
1456         return 0;
1457 }
1458
1459 /*
1460  * Dispose of the state data for the drives control loop
1461  */
1462 static void dispose_drives_state(struct drives_pid_state *state)
1463 {
1464         if (state->monitor == NULL)
1465                 return;
1466
1467         device_remove_file(&of_dev->dev, &dev_attr_drives_temperature);
1468         device_remove_file(&of_dev->dev, &dev_attr_drives_fan_rpm);
1469
1470         detach_i2c_chip(state->monitor);
1471         state->monitor = NULL;
1472 }
1473
1474 /*
1475  * DIMMs temp control loop
1476  */
1477 static void do_monitor_dimms(struct dimm_pid_state *state)
1478 {
1479         s32 temp, integral, derivative, fan_min;
1480         s64 integ_p, deriv_p, prop_p, sum;
1481         int i;
1482
1483         if (--state->ticks != 0)
1484                 return;
1485         state->ticks = DIMM_PID_INTERVAL;
1486
1487         DBG("DIMM:\n");
1488
1489         DBG("  current value: %d\n", state->output);
1490
1491         temp = read_lm87_reg(state->monitor, LM87_INT_TEMP);
1492         if (temp < 0)
1493                 return;
1494         temp <<= 16;
1495         state->last_temp = temp;
1496         DBG("  temp: %d.%03d, target: %d.%03d\n", FIX32TOPRINT(temp),
1497             FIX32TOPRINT(DIMM_PID_INPUT_TARGET));
1498
1499         /* Store temperature and error in history array */
1500         state->cur_sample = (state->cur_sample + 1) % DIMM_PID_HISTORY_SIZE;
1501         state->sample_history[state->cur_sample] = temp;
1502         state->error_history[state->cur_sample] = temp - DIMM_PID_INPUT_TARGET;
1503
1504         /* If first loop, fill the history table */
1505         if (state->first) {
1506                 for (i = 0; i < (DIMM_PID_HISTORY_SIZE - 1); i++) {
1507                         state->cur_sample = (state->cur_sample + 1) %
1508                                 DIMM_PID_HISTORY_SIZE;
1509                         state->sample_history[state->cur_sample] = temp;
1510                         state->error_history[state->cur_sample] =
1511                                 temp - DIMM_PID_INPUT_TARGET;
1512                 }
1513                 state->first = 0;
1514         }
1515
1516         /* Calculate the integral term */
1517         sum = 0;
1518         integral = 0;
1519         for (i = 0; i < DIMM_PID_HISTORY_SIZE; i++)
1520                 integral += state->error_history[i];
1521         integral *= DIMM_PID_INTERVAL;
1522         DBG("  integral: %08x\n", integral);
1523         integ_p = ((s64)DIMM_PID_G_r) * (s64)integral;
1524         DBG("   integ_p: %d\n", (int)(integ_p >> 36));
1525         sum += integ_p;
1526
1527         /* Calculate the derivative term */
1528         derivative = state->error_history[state->cur_sample] -
1529                 state->error_history[(state->cur_sample + DIMM_PID_HISTORY_SIZE - 1)
1530                                     % DIMM_PID_HISTORY_SIZE];
1531         derivative /= DIMM_PID_INTERVAL;
1532         deriv_p = ((s64)DIMM_PID_G_d) * (s64)derivative;
1533         DBG("   deriv_p: %d\n", (int)(deriv_p >> 36));
1534         sum += deriv_p;
1535
1536         /* Calculate the proportional term */
1537         prop_p = ((s64)DIMM_PID_G_p) * (s64)(state->error_history[state->cur_sample]);
1538         DBG("   prop_p: %d\n", (int)(prop_p >> 36));
1539         sum += prop_p;
1540
1541         /* Scale sum */
1542         sum >>= 36;
1543
1544         DBG("   sum: %d\n", (int)sum);
1545         state->output = (s32)sum;
1546         state->output = max(state->output, DIMM_PID_OUTPUT_MIN);
1547         state->output = min(state->output, DIMM_PID_OUTPUT_MAX);
1548         dimm_output_clamp = state->output;
1549
1550         DBG("** DIMM clamp value: %d\n", (int)state->output);
1551
1552         /* Backside PID is only every 5 seconds, force backside fan clamping now */
1553         fan_min = (dimm_output_clamp * 100) / 14000;
1554         fan_min = max(fan_min, backside_params.output_min);
1555         if (backside_state.pwm < fan_min) {
1556                 backside_state.pwm = fan_min;
1557                 DBG(" -> applying clamp to backside fan now: %d  !\n", fan_min);
1558                 set_pwm_fan(BACKSIDE_FAN_PWM_INDEX, fan_min);
1559         }
1560 }
1561
1562 /*
1563  * Initialize the state structure for the DIMM temp control loop
1564  */
1565 static int init_dimms_state(struct dimm_pid_state *state)
1566 {
1567         state->ticks = 1;
1568         state->first = 1;
1569         state->output = 4000;
1570
1571         state->monitor = attach_i2c_chip(XSERVE_DIMMS_LM87, "dimms_temp");
1572         if (state->monitor == NULL)
1573                 return -ENODEV;
1574
1575         device_create_file(&of_dev->dev, &dev_attr_dimms_temperature);
1576
1577         return 0;
1578 }
1579
1580 /*
1581  * Dispose of the state data for the drives control loop
1582  */
1583 static void dispose_dimms_state(struct dimm_pid_state *state)
1584 {
1585         if (state->monitor == NULL)
1586                 return;
1587
1588         device_remove_file(&of_dev->dev, &dev_attr_dimms_temperature);
1589
1590         detach_i2c_chip(state->monitor);
1591         state->monitor = NULL;
1592 }
1593
1594 static int call_critical_overtemp(void)
1595 {
1596         char *argv[] = { critical_overtemp_path, NULL };
1597         static char *envp[] = { "HOME=/",
1598                                 "TERM=linux",
1599                                 "PATH=/sbin:/usr/sbin:/bin:/usr/bin",
1600                                 NULL };
1601
1602         return call_usermodehelper(critical_overtemp_path, argv, envp, 0);
1603 }
1604
1605
1606 /*
1607  * Here's the kernel thread that calls the various control loops
1608  */
1609 static int main_control_loop(void *x)
1610 {
1611         daemonize("kfand");
1612
1613         DBG("main_control_loop started\n");
1614
1615         down(&driver_lock);
1616
1617         if (start_fcu() < 0) {
1618                 printk(KERN_ERR "kfand: failed to start FCU\n");
1619                 up(&driver_lock);
1620                 goto out;
1621         }
1622
1623         /* Set the PCI fan once for now */
1624         set_pwm_fan(SLOTS_FAN_PWM_INDEX, SLOTS_FAN_DEFAULT_PWM);
1625
1626         /* Initialize ADCs */
1627         initialize_adc(&cpu_state[0]);
1628         if (cpu_state[1].monitor != NULL)
1629                 initialize_adc(&cpu_state[1]);
1630
1631         up(&driver_lock);
1632
1633         while (state == state_attached) {
1634                 unsigned long elapsed, start;
1635
1636                 start = jiffies;
1637
1638                 down(&driver_lock);
1639
1640                 /* First, we always calculate the new DIMMs state on an Xserve */
1641                 if (rackmac)
1642                         do_monitor_dimms(&dimms_state);
1643
1644                 /* Then, the CPUs */
1645                 if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1646                         do_monitor_cpu_combined();
1647                 else if (cpu_pid_type == CPU_PID_TYPE_RACKMAC) {
1648                         do_monitor_cpu_rack(&cpu_state[0]);
1649                         if (cpu_state[1].monitor != NULL)
1650                                 do_monitor_cpu_rack(&cpu_state[1]);
1651                         // better deal with UP
1652                 } else {
1653                         do_monitor_cpu_split(&cpu_state[0]);
1654                         if (cpu_state[1].monitor != NULL)
1655                                 do_monitor_cpu_split(&cpu_state[1]);
1656                         // better deal with UP
1657                 }
1658                 /* Then, the rest */
1659                 do_monitor_backside(&backside_state);
1660                 if (!rackmac)
1661                         do_monitor_drives(&drives_state);
1662                 up(&driver_lock);
1663
1664                 if (critical_state == 1) {
1665                         printk(KERN_WARNING "Temperature control detected a critical condition\n");
1666                         printk(KERN_WARNING "Attempting to shut down...\n");
1667                         if (call_critical_overtemp()) {
1668                                 printk(KERN_WARNING "Can't call %s, power off now!\n",
1669                                        critical_overtemp_path);
1670                                 machine_power_off();
1671                         }
1672                 }
1673                 if (critical_state > 0)
1674                         critical_state++;
1675                 if (critical_state > MAX_CRITICAL_STATE) {
1676                         printk(KERN_WARNING "Shutdown timed out, power off now !\n");
1677                         machine_power_off();
1678                 }
1679
1680                 // FIXME: Deal with signals
1681                 set_current_state(TASK_INTERRUPTIBLE);
1682                 elapsed = jiffies - start;
1683                 if (elapsed < HZ)
1684                         schedule_timeout(HZ - elapsed);
1685         }
1686
1687  out:
1688         DBG("main_control_loop ended\n");
1689
1690         ctrl_task = 0;
1691         complete_and_exit(&ctrl_complete, 0);
1692 }
1693
1694 /*
1695  * Dispose the control loops when tearing down
1696  */
1697 static void dispose_control_loops(void)
1698 {
1699         dispose_cpu_state(&cpu_state[0]);
1700         dispose_cpu_state(&cpu_state[1]);
1701         dispose_backside_state(&backside_state);
1702         dispose_drives_state(&drives_state);
1703         dispose_dimms_state(&dimms_state);
1704 }
1705
1706 /*
1707  * Create the control loops. U3-0 i2c bus is up, so we can now
1708  * get to the various sensors
1709  */
1710 static int create_control_loops(void)
1711 {
1712         struct device_node *np;
1713
1714         /* Count CPUs from the device-tree, we don't care how many are
1715          * actually used by Linux
1716          */
1717         cpu_count = 0;
1718         for (np = NULL; NULL != (np = of_find_node_by_type(np, "cpu"));)
1719                 cpu_count++;
1720
1721         DBG("counted %d CPUs in the device-tree\n", cpu_count);
1722
1723         /* Decide the type of PID algorithm to use based on the presence of
1724          * the pumps, though that may not be the best way, that is good enough
1725          * for now
1726          */
1727         if (rackmac)
1728                 cpu_pid_type = CPU_PID_TYPE_RACKMAC;
1729         else if (machine_is_compatible("PowerMac7,3")
1730             && (cpu_count > 1)
1731             && fcu_fans[CPUA_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID
1732             && fcu_fans[CPUB_PUMP_RPM_INDEX].id != FCU_FAN_ABSENT_ID) {
1733                 printk(KERN_INFO "Liquid cooling pumps detected, using new algorithm !\n");
1734                 cpu_pid_type = CPU_PID_TYPE_COMBINED;
1735         } else
1736                 cpu_pid_type = CPU_PID_TYPE_SPLIT;
1737
1738         /* Create control loops for everything. If any fail, everything
1739          * fails
1740          */
1741         if (init_cpu_state(&cpu_state[0], 0))
1742                 goto fail;
1743         if (cpu_pid_type == CPU_PID_TYPE_COMBINED)
1744                 fetch_cpu_pumps_minmax();
1745
1746         if (cpu_count > 1 && init_cpu_state(&cpu_state[1], 1))
1747                 goto fail;
1748         if (init_backside_state(&backside_state))
1749                 goto fail;
1750         if (rackmac && init_dimms_state(&dimms_state))
1751                 goto fail;
1752         if (!rackmac && init_drives_state(&drives_state))
1753                 goto fail;
1754
1755         DBG("all control loops up !\n");
1756
1757         return 0;
1758         
1759  fail:
1760         DBG("failure creating control loops, disposing\n");
1761
1762         dispose_control_loops();
1763
1764         return -ENODEV;
1765 }
1766
1767 /*
1768  * Start the control loops after everything is up, that is create
1769  * the thread that will make them run
1770  */
1771 static void start_control_loops(void)
1772 {
1773         init_completion(&ctrl_complete);
1774
1775         ctrl_task = kernel_thread(main_control_loop, NULL, SIGCHLD | CLONE_KERNEL);
1776 }
1777
1778 /*
1779  * Stop the control loops when tearing down
1780  */
1781 static void stop_control_loops(void)
1782 {
1783         if (ctrl_task != 0)
1784                 wait_for_completion(&ctrl_complete);
1785 }
1786
1787 /*
1788  * Attach to the i2c FCU after detecting U3-1 bus
1789  */
1790 static int attach_fcu(void)
1791 {
1792         fcu = attach_i2c_chip(FAN_CTRLER_ID, "fcu");
1793         if (fcu == NULL)
1794                 return -ENODEV;
1795
1796         DBG("FCU attached\n");
1797
1798         return 0;
1799 }
1800
1801 /*
1802  * Detach from the i2c FCU when tearing down
1803  */
1804 static void detach_fcu(void)
1805 {
1806         if (fcu)
1807                 detach_i2c_chip(fcu);
1808         fcu = NULL;
1809 }
1810
1811 /*
1812  * Attach to the i2c controller. We probe the various chips based
1813  * on the device-tree nodes and build everything for the driver to
1814  * run, we then kick the driver monitoring thread
1815  */
1816 static int therm_pm72_attach(struct i2c_adapter *adapter)
1817 {
1818         down(&driver_lock);
1819
1820         /* Check state */
1821         if (state == state_detached)
1822                 state = state_attaching;
1823         if (state != state_attaching) {
1824                 up(&driver_lock);
1825                 return 0;
1826         }
1827
1828         /* Check if we are looking for one of these */
1829         if (u3_0 == NULL && !strcmp(adapter->name, "u3 0")) {
1830                 u3_0 = adapter;
1831                 DBG("found U3-0\n");
1832                 if (k2 || !rackmac)
1833                         if (create_control_loops())
1834                                 u3_0 = NULL;
1835         } else if (u3_1 == NULL && !strcmp(adapter->name, "u3 1")) {
1836                 u3_1 = adapter;
1837                 DBG("found U3-1, attaching FCU\n");
1838                 if (attach_fcu())
1839                         u3_1 = NULL;
1840         } else if (k2 == NULL && !strcmp(adapter->name, "mac-io 0")) {
1841                 k2 = adapter;
1842                 DBG("Found K2\n");
1843                 if (u3_0 && rackmac)
1844                         if (create_control_loops())
1845                                 k2 = NULL;
1846         }
1847         /* We got all we need, start control loops */
1848         if (u3_0 != NULL && u3_1 != NULL && (k2 || !rackmac)) {
1849                 DBG("everything up, starting control loops\n");
1850                 state = state_attached;
1851                 start_control_loops();
1852         }
1853         up(&driver_lock);
1854
1855         return 0;
1856 }
1857
1858 /*
1859  * Called on every adapter when the driver or the i2c controller
1860  * is going away.
1861  */
1862 static int therm_pm72_detach(struct i2c_adapter *adapter)
1863 {
1864         down(&driver_lock);
1865
1866         if (state != state_detached)
1867                 state = state_detaching;
1868
1869         /* Stop control loops if any */
1870         DBG("stopping control loops\n");
1871         up(&driver_lock);
1872         stop_control_loops();
1873         down(&driver_lock);
1874
1875         if (u3_0 != NULL && !strcmp(adapter->name, "u3 0")) {
1876                 DBG("lost U3-0, disposing control loops\n");
1877                 dispose_control_loops();
1878                 u3_0 = NULL;
1879         }
1880         
1881         if (u3_1 != NULL && !strcmp(adapter->name, "u3 1")) {
1882                 DBG("lost U3-1, detaching FCU\n");
1883                 detach_fcu();
1884                 u3_1 = NULL;
1885         }
1886         if (u3_0 == NULL && u3_1 == NULL)
1887                 state = state_detached;
1888
1889         up(&driver_lock);
1890
1891         return 0;
1892 }
1893
1894 static int fan_check_loc_match(const char *loc, int fan)
1895 {
1896         char    tmp[64];
1897         char    *c, *e;
1898
1899         strlcpy(tmp, fcu_fans[fan].loc, 64);
1900
1901         c = tmp;
1902         for (;;) {
1903                 e = strchr(c, ',');
1904                 if (e)
1905                         *e = 0;
1906                 if (strcmp(loc, c) == 0)
1907                         return 1;
1908                 if (e == NULL)
1909                         break;
1910                 c = e + 1;
1911         }
1912         return 0;
1913 }
1914
1915 static void fcu_lookup_fans(struct device_node *fcu_node)
1916 {
1917         struct device_node *np = NULL;
1918         int i;
1919
1920         /* The table is filled by default with values that are suitable
1921          * for the old machines without device-tree informations. We scan
1922          * the device-tree and override those values with whatever is
1923          * there
1924          */
1925
1926         DBG("Looking up FCU controls in device-tree...\n");
1927
1928         while ((np = of_get_next_child(fcu_node, np)) != NULL) {
1929                 int type = -1;
1930                 char *loc;
1931                 u32 *reg;
1932
1933                 DBG(" control: %s, type: %s\n", np->name, np->type);
1934
1935                 /* Detect control type */
1936                 if (!strcmp(np->type, "fan-rpm-control") ||
1937                     !strcmp(np->type, "fan-rpm"))
1938                         type = FCU_FAN_RPM;
1939                 if (!strcmp(np->type, "fan-pwm-control") ||
1940                     !strcmp(np->type, "fan-pwm"))
1941                         type = FCU_FAN_PWM;
1942                 /* Only care about fans for now */
1943                 if (type == -1)
1944                         continue;
1945
1946                 /* Lookup for a matching location */
1947                 loc = (char *)get_property(np, "location", NULL);
1948                 reg = (u32 *)get_property(np, "reg", NULL);
1949                 if (loc == NULL || reg == NULL)
1950                         continue;
1951                 DBG(" matching location: %s, reg: 0x%08x\n", loc, *reg);
1952
1953                 for (i = 0; i < FCU_FAN_COUNT; i++) {
1954                         int fan_id;
1955
1956                         if (!fan_check_loc_match(loc, i))
1957                                 continue;
1958                         DBG(" location match, index: %d\n", i);
1959                         fcu_fans[i].id = FCU_FAN_ABSENT_ID;
1960                         if (type != fcu_fans[i].type) {
1961                                 printk(KERN_WARNING "therm_pm72: Fan type mismatch "
1962                                        "in device-tree for %s\n", np->full_name);
1963                                 break;
1964                         }
1965                         if (type == FCU_FAN_RPM)
1966                                 fan_id = ((*reg) - 0x10) / 2;
1967                         else
1968                                 fan_id = ((*reg) - 0x30) / 2;
1969                         if (fan_id > 7) {
1970                                 printk(KERN_WARNING "therm_pm72: Can't parse "
1971                                        "fan ID in device-tree for %s\n", np->full_name);
1972                                 break;
1973                         }
1974                         DBG(" fan id -> %d, type -> %d\n", fan_id, type);
1975                         fcu_fans[i].id = fan_id;
1976                 }
1977         }
1978
1979         /* Now dump the array */
1980         printk(KERN_INFO "Detected fan controls:\n");
1981         for (i = 0; i < FCU_FAN_COUNT; i++) {
1982                 if (fcu_fans[i].id == FCU_FAN_ABSENT_ID)
1983                         continue;
1984                 printk(KERN_INFO "  %d: %s fan, id %d, location: %s\n", i,
1985                        fcu_fans[i].type == FCU_FAN_RPM ? "RPM" : "PWM",
1986                        fcu_fans[i].id, fcu_fans[i].loc);
1987         }
1988 }
1989
1990 static int fcu_of_probe(struct of_device* dev, const struct of_device_id *match)
1991 {
1992         int rc;
1993
1994         state = state_detached;
1995
1996         /* Lookup the fans in the device tree */
1997         fcu_lookup_fans(dev->node);
1998
1999         /* Add the driver */
2000         rc = i2c_add_driver(&therm_pm72_driver);
2001         if (rc < 0)
2002                 return rc;
2003         return 0;
2004 }
2005
2006 static int fcu_of_remove(struct of_device* dev)
2007 {
2008         i2c_del_driver(&therm_pm72_driver);
2009
2010         return 0;
2011 }
2012
2013 static struct of_device_id fcu_match[] = 
2014 {
2015         {
2016         .type           = "fcu",
2017         },
2018         {},
2019 };
2020
2021 static struct of_platform_driver fcu_of_platform_driver = 
2022 {
2023         .name           = "temperature",
2024         .match_table    = fcu_match,
2025         .probe          = fcu_of_probe,
2026         .remove         = fcu_of_remove
2027 };
2028
2029 /*
2030  * Check machine type, attach to i2c controller
2031  */
2032 static int __init therm_pm72_init(void)
2033 {
2034         struct device_node *np;
2035
2036         rackmac = machine_is_compatible("RackMac3,1");
2037
2038         if (!machine_is_compatible("PowerMac7,2") &&
2039             !machine_is_compatible("PowerMac7,3") &&
2040             !rackmac)
2041                 return -ENODEV;
2042
2043         printk(KERN_INFO "PowerMac G5 Thermal control driver %s\n", VERSION);
2044
2045         np = of_find_node_by_type(NULL, "fcu");
2046         if (np == NULL) {
2047                 /* Some machines have strangely broken device-tree */
2048                 np = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/fan@15e");
2049                 if (np == NULL) {
2050                             printk(KERN_ERR "Can't find FCU in device-tree !\n");
2051                             return -ENODEV;
2052                 }
2053         }
2054         of_dev = of_platform_device_create(np, "temperature");
2055         if (of_dev == NULL) {
2056                 printk(KERN_ERR "Can't register FCU platform device !\n");
2057                 return -ENODEV;
2058         }
2059
2060         of_register_driver(&fcu_of_platform_driver);
2061         
2062         return 0;
2063 }
2064
2065 static void __exit therm_pm72_exit(void)
2066 {
2067         of_unregister_driver(&fcu_of_platform_driver);
2068
2069         if (of_dev)
2070                 of_device_unregister(of_dev);
2071 }
2072
2073 module_init(therm_pm72_init);
2074 module_exit(therm_pm72_exit);
2075
2076 MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
2077 MODULE_DESCRIPTION("Driver for Apple's PowerMac G5 thermal control");
2078 MODULE_LICENSE("GPL");
2079