Merge branch 'simplify_PRT' into release
[linux-2.6] / drivers / macintosh / windfarm_smu_sat.c
1 /*
2  * Windfarm PowerMac thermal control.  SMU "satellite" controller sensors.
3  *
4  * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
5  *
6  * Released under the terms of the GNU GPL v2.
7  */
8
9 #include <linux/types.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/init.h>
14 #include <linux/wait.h>
15 #include <linux/i2c.h>
16 #include <linux/mutex.h>
17 #include <asm/prom.h>
18 #include <asm/smu.h>
19 #include <asm/pmac_low_i2c.h>
20
21 #include "windfarm.h"
22
23 #define VERSION "0.2"
24
25 #define DEBUG
26
27 #ifdef DEBUG
28 #define DBG(args...)    printk(args)
29 #else
30 #define DBG(args...)    do { } while(0)
31 #endif
32
33 /* If the cache is older than 800ms we'll refetch it */
34 #define MAX_AGE         msecs_to_jiffies(800)
35
36 struct wf_sat {
37         int                     nr;
38         atomic_t                refcnt;
39         struct mutex            mutex;
40         unsigned long           last_read; /* jiffies when cache last updated */
41         u8                      cache[16];
42         struct i2c_client       i2c;
43         struct device_node      *node;
44 };
45
46 static struct wf_sat *sats[2];
47
48 struct wf_sat_sensor {
49         int             index;
50         int             index2;         /* used for power sensors */
51         int             shift;
52         struct wf_sat   *sat;
53         struct wf_sensor sens;
54 };
55
56 #define wf_to_sat(c)    container_of(c, struct wf_sat_sensor, sens)
57 #define i2c_to_sat(c)   container_of(c, struct wf_sat, i2c)
58
59 static int wf_sat_attach(struct i2c_adapter *adapter);
60 static int wf_sat_detach(struct i2c_client *client);
61
62 static struct i2c_driver wf_sat_driver = {
63         .driver = {
64                 .name           = "wf_smu_sat",
65         },
66         .attach_adapter = wf_sat_attach,
67         .detach_client  = wf_sat_detach,
68 };
69
70 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
71                                                   unsigned int *size)
72 {
73         struct wf_sat *sat;
74         int err;
75         unsigned int i, len;
76         u8 *buf;
77         u8 data[4];
78
79         /* TODO: Add the resulting partition to the device-tree */
80
81         if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
82                 return NULL;
83
84         err = i2c_smbus_write_word_data(&sat->i2c, 8, id << 8);
85         if (err) {
86                 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
87                 return NULL;
88         }
89
90         err = i2c_smbus_read_word_data(&sat->i2c, 9);
91         if (err < 0) {
92                 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
93                 return NULL;
94         }
95         len = err;
96         if (len == 0) {
97                 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
98                 return NULL;
99         }
100
101         len = le16_to_cpu(len);
102         len = (len + 3) & ~3;
103         buf = kmalloc(len, GFP_KERNEL);
104         if (buf == NULL)
105                 return NULL;
106
107         for (i = 0; i < len; i += 4) {
108                 err = i2c_smbus_read_i2c_block_data(&sat->i2c, 0xa, 4, data);
109                 if (err < 0) {
110                         printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
111                                err);
112                         goto fail;
113                 }
114                 buf[i] = data[1];
115                 buf[i+1] = data[0];
116                 buf[i+2] = data[3];
117                 buf[i+3] = data[2];
118         }
119 #ifdef DEBUG
120         DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id);
121         for (i = 0; i < len; ++i)
122                 DBG(" %x", buf[i]);
123         DBG("\n");
124 #endif
125
126         if (size)
127                 *size = len;
128         return (struct smu_sdbp_header *) buf;
129
130  fail:
131         kfree(buf);
132         return NULL;
133 }
134 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);
135
136 /* refresh the cache */
137 static int wf_sat_read_cache(struct wf_sat *sat)
138 {
139         int err;
140
141         err = i2c_smbus_read_i2c_block_data(&sat->i2c, 0x3f, 16, sat->cache);
142         if (err < 0)
143                 return err;
144         sat->last_read = jiffies;
145 #ifdef LOTSA_DEBUG
146         {
147                 int i;
148                 DBG(KERN_DEBUG "wf_sat_get: data is");
149                 for (i = 0; i < 16; ++i)
150                         DBG(" %.2x", sat->cache[i]);
151                 DBG("\n");
152         }
153 #endif
154         return 0;
155 }
156
157 static int wf_sat_get(struct wf_sensor *sr, s32 *value)
158 {
159         struct wf_sat_sensor *sens = wf_to_sat(sr);
160         struct wf_sat *sat = sens->sat;
161         int i, err;
162         s32 val;
163
164         if (sat->i2c.adapter == NULL)
165                 return -ENODEV;
166
167         mutex_lock(&sat->mutex);
168         if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
169                 err = wf_sat_read_cache(sat);
170                 if (err)
171                         goto fail;
172         }
173
174         i = sens->index * 2;
175         val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
176         if (sens->index2 >= 0) {
177                 i = sens->index2 * 2;
178                 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
179                 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
180         }
181
182         *value = val;
183         err = 0;
184
185  fail:
186         mutex_unlock(&sat->mutex);
187         return err;
188 }
189
190 static void wf_sat_release(struct wf_sensor *sr)
191 {
192         struct wf_sat_sensor *sens = wf_to_sat(sr);
193         struct wf_sat *sat = sens->sat;
194
195         if (atomic_dec_and_test(&sat->refcnt)) {
196                 if (sat->i2c.adapter) {
197                         i2c_detach_client(&sat->i2c);
198                         sat->i2c.adapter = NULL;
199                 }
200                 if (sat->nr >= 0)
201                         sats[sat->nr] = NULL;
202                 kfree(sat);
203         }
204         kfree(sens);
205 }
206
207 static struct wf_sensor_ops wf_sat_ops = {
208         .get_value      = wf_sat_get,
209         .release        = wf_sat_release,
210         .owner          = THIS_MODULE,
211 };
212
213 static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev)
214 {
215         struct wf_sat *sat;
216         struct wf_sat_sensor *sens;
217         const u32 *reg;
218         const char *loc, *type;
219         u8 addr, chip, core;
220         struct device_node *child;
221         int shift, cpu, index;
222         char *name;
223         int vsens[2], isens[2];
224
225         reg = of_get_property(dev, "reg", NULL);
226         if (reg == NULL)
227                 return;
228         addr = *reg;
229         DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr);
230
231         sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
232         if (sat == NULL)
233                 return;
234         sat->nr = -1;
235         sat->node = of_node_get(dev);
236         atomic_set(&sat->refcnt, 0);
237         mutex_init(&sat->mutex);
238         sat->i2c.addr = (addr >> 1) & 0x7f;
239         sat->i2c.adapter = adapter;
240         sat->i2c.driver = &wf_sat_driver;
241         strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1);
242
243         if (i2c_attach_client(&sat->i2c)) {
244                 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n");
245                 goto fail;
246         }
247
248         vsens[0] = vsens[1] = -1;
249         isens[0] = isens[1] = -1;
250         child = NULL;
251         while ((child = of_get_next_child(dev, child)) != NULL) {
252                 reg = of_get_property(child, "reg", NULL);
253                 type = of_get_property(child, "device_type", NULL);
254                 loc = of_get_property(child, "location", NULL);
255                 if (reg == NULL || loc == NULL)
256                         continue;
257
258                 /* the cooked sensors are between 0x30 and 0x37 */
259                 if (*reg < 0x30 || *reg > 0x37)
260                         continue;
261                 index = *reg - 0x30;
262
263                 /* expect location to be CPU [AB][01] ... */
264                 if (strncmp(loc, "CPU ", 4) != 0)
265                         continue;
266                 chip = loc[4] - 'A';
267                 core = loc[5] - '0';
268                 if (chip > 1 || core > 1) {
269                         printk(KERN_ERR "wf_sat_create: don't understand "
270                                "location %s for %s\n", loc, child->full_name);
271                         continue;
272                 }
273                 cpu = 2 * chip + core;
274                 if (sat->nr < 0)
275                         sat->nr = chip;
276                 else if (sat->nr != chip) {
277                         printk(KERN_ERR "wf_sat_create: can't cope with "
278                                "multiple CPU chips on one SAT (%s)\n", loc);
279                         continue;
280                 }
281
282                 if (strcmp(type, "voltage-sensor") == 0) {
283                         name = "cpu-voltage";
284                         shift = 4;
285                         vsens[core] = index;
286                 } else if (strcmp(type, "current-sensor") == 0) {
287                         name = "cpu-current";
288                         shift = 8;
289                         isens[core] = index;
290                 } else if (strcmp(type, "temp-sensor") == 0) {
291                         name = "cpu-temp";
292                         shift = 10;
293                 } else
294                         continue;       /* hmmm shouldn't happen */
295
296                 /* the +16 is enough for "cpu-voltage-n" */
297                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
298                 if (sens == NULL) {
299                         printk(KERN_ERR "wf_sat_create: couldn't create "
300                                "%s sensor %d (no memory)\n", name, cpu);
301                         continue;
302                 }
303                 sens->index = index;
304                 sens->index2 = -1;
305                 sens->shift = shift;
306                 sens->sat = sat;
307                 atomic_inc(&sat->refcnt);
308                 sens->sens.ops = &wf_sat_ops;
309                 sens->sens.name = (char *) (sens + 1);
310                 snprintf(sens->sens.name, 16, "%s-%d", name, cpu);
311
312                 if (wf_register_sensor(&sens->sens)) {
313                         atomic_dec(&sat->refcnt);
314                         kfree(sens);
315                 }
316         }
317
318         /* make the power sensors */
319         for (core = 0; core < 2; ++core) {
320                 if (vsens[core] < 0 || isens[core] < 0)
321                         continue;
322                 cpu = 2 * sat->nr + core;
323                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
324                 if (sens == NULL) {
325                         printk(KERN_ERR "wf_sat_create: couldn't create power "
326                                "sensor %d (no memory)\n", cpu);
327                         continue;
328                 }
329                 sens->index = vsens[core];
330                 sens->index2 = isens[core];
331                 sens->shift = 0;
332                 sens->sat = sat;
333                 atomic_inc(&sat->refcnt);
334                 sens->sens.ops = &wf_sat_ops;
335                 sens->sens.name = (char *) (sens + 1);
336                 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu);
337
338                 if (wf_register_sensor(&sens->sens)) {
339                         atomic_dec(&sat->refcnt);
340                         kfree(sens);
341                 }
342         }
343
344         if (sat->nr >= 0)
345                 sats[sat->nr] = sat;
346
347         return;
348
349  fail:
350         kfree(sat);
351 }
352
353 static int wf_sat_attach(struct i2c_adapter *adapter)
354 {
355         struct device_node *busnode, *dev = NULL;
356         struct pmac_i2c_bus *bus;
357
358         bus = pmac_i2c_adapter_to_bus(adapter);
359         if (bus == NULL)
360                 return -ENODEV;
361         busnode = pmac_i2c_get_bus_node(bus);
362
363         while ((dev = of_get_next_child(busnode, dev)) != NULL)
364                 if (of_device_is_compatible(dev, "smu-sat"))
365                         wf_sat_create(adapter, dev);
366         return 0;
367 }
368
369 static int wf_sat_detach(struct i2c_client *client)
370 {
371         struct wf_sat *sat = i2c_to_sat(client);
372
373         /* XXX TODO */
374
375         sat->i2c.adapter = NULL;
376         return 0;
377 }
378
379 static int __init sat_sensors_init(void)
380 {
381         return i2c_add_driver(&wf_sat_driver);
382 }
383
384 #if 0   /* uncomment when module_exit() below is uncommented */
385 static void __exit sat_sensors_exit(void)
386 {
387         i2c_del_driver(&wf_sat_driver);
388 }
389 #endif
390
391 module_init(sat_sensors_init);
392 /*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */
393
394 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
395 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
396 MODULE_LICENSE("GPL");