i2c: Fix the i2c_smbus_read_i2c_block_data() prototype
[linux-2.6.git] / 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 <asm/semaphore.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 semaphore        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         len = i2c_smbus_read_word_data(&sat->i2c, 9);
91         if (len < 0) {
92                 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
93                 return NULL;
94         }
95         if (len == 0) {
96                 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
97                 return NULL;
98         }
99
100         len = le16_to_cpu(len);
101         len = (len + 3) & ~3;
102         buf = kmalloc(len, GFP_KERNEL);
103         if (buf == NULL)
104                 return NULL;
105
106         for (i = 0; i < len; i += 4) {
107                 err = i2c_smbus_read_i2c_block_data(&sat->i2c, 0xa, 4, data);
108                 if (err < 0) {
109                         printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
110                                err);
111                         goto fail;
112                 }
113                 buf[i] = data[1];
114                 buf[i+1] = data[0];
115                 buf[i+2] = data[3];
116                 buf[i+3] = data[2];
117         }
118 #ifdef DEBUG
119         DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id);
120         for (i = 0; i < len; ++i)
121                 DBG(" %x", buf[i]);
122         DBG("\n");
123 #endif
124
125         if (size)
126                 *size = len;
127         return (struct smu_sdbp_header *) buf;
128
129  fail:
130         kfree(buf);
131         return NULL;
132 }
133 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);
134
135 /* refresh the cache */
136 static int wf_sat_read_cache(struct wf_sat *sat)
137 {
138         int err;
139
140         err = i2c_smbus_read_i2c_block_data(&sat->i2c, 0x3f, 16, sat->cache);
141         if (err < 0)
142                 return err;
143         sat->last_read = jiffies;
144 #ifdef LOTSA_DEBUG
145         {
146                 int i;
147                 DBG(KERN_DEBUG "wf_sat_get: data is");
148                 for (i = 0; i < 16; ++i)
149                         DBG(" %.2x", sat->cache[i]);
150                 DBG("\n");
151         }
152 #endif
153         return 0;
154 }
155
156 static int wf_sat_get(struct wf_sensor *sr, s32 *value)
157 {
158         struct wf_sat_sensor *sens = wf_to_sat(sr);
159         struct wf_sat *sat = sens->sat;
160         int i, err;
161         s32 val;
162
163         if (sat->i2c.adapter == NULL)
164                 return -ENODEV;
165
166         down(&sat->mutex);
167         if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
168                 err = wf_sat_read_cache(sat);
169                 if (err)
170                         goto fail;
171         }
172
173         i = sens->index * 2;
174         val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
175         if (sens->index2 >= 0) {
176                 i = sens->index2 * 2;
177                 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
178                 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
179         }
180
181         *value = val;
182         err = 0;
183
184  fail:
185         up(&sat->mutex);
186         return err;
187 }
188
189 static void wf_sat_release(struct wf_sensor *sr)
190 {
191         struct wf_sat_sensor *sens = wf_to_sat(sr);
192         struct wf_sat *sat = sens->sat;
193
194         if (atomic_dec_and_test(&sat->refcnt)) {
195                 if (sat->i2c.adapter) {
196                         i2c_detach_client(&sat->i2c);
197                         sat->i2c.adapter = NULL;
198                 }
199                 if (sat->nr >= 0)
200                         sats[sat->nr] = NULL;
201                 kfree(sat);
202         }
203         kfree(sens);
204 }
205
206 static struct wf_sensor_ops wf_sat_ops = {
207         .get_value      = wf_sat_get,
208         .release        = wf_sat_release,
209         .owner          = THIS_MODULE,
210 };
211
212 static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev)
213 {
214         struct wf_sat *sat;
215         struct wf_sat_sensor *sens;
216         const u32 *reg;
217         const char *loc, *type;
218         u8 addr, chip, core;
219         struct device_node *child;
220         int shift, cpu, index;
221         char *name;
222         int vsens[2], isens[2];
223
224         reg = of_get_property(dev, "reg", NULL);
225         if (reg == NULL)
226                 return;
227         addr = *reg;
228         DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr);
229
230         sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
231         if (sat == NULL)
232                 return;
233         sat->nr = -1;
234         sat->node = of_node_get(dev);
235         atomic_set(&sat->refcnt, 0);
236         init_MUTEX(&sat->mutex);
237         sat->i2c.addr = (addr >> 1) & 0x7f;
238         sat->i2c.adapter = adapter;
239         sat->i2c.driver = &wf_sat_driver;
240         strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1);
241
242         if (i2c_attach_client(&sat->i2c)) {
243                 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n");
244                 goto fail;
245         }
246
247         vsens[0] = vsens[1] = -1;
248         isens[0] = isens[1] = -1;
249         child = NULL;
250         while ((child = of_get_next_child(dev, child)) != NULL) {
251                 reg = of_get_property(child, "reg", NULL);
252                 type = of_get_property(child, "device_type", NULL);
253                 loc = of_get_property(child, "location", NULL);
254                 if (reg == NULL || loc == NULL)
255                         continue;
256
257                 /* the cooked sensors are between 0x30 and 0x37 */
258                 if (*reg < 0x30 || *reg > 0x37)
259                         continue;
260                 index = *reg - 0x30;
261
262                 /* expect location to be CPU [AB][01] ... */
263                 if (strncmp(loc, "CPU ", 4) != 0)
264                         continue;
265                 chip = loc[4] - 'A';
266                 core = loc[5] - '0';
267                 if (chip > 1 || core > 1) {
268                         printk(KERN_ERR "wf_sat_create: don't understand "
269                                "location %s for %s\n", loc, child->full_name);
270                         continue;
271                 }
272                 cpu = 2 * chip + core;
273                 if (sat->nr < 0)
274                         sat->nr = chip;
275                 else if (sat->nr != chip) {
276                         printk(KERN_ERR "wf_sat_create: can't cope with "
277                                "multiple CPU chips on one SAT (%s)\n", loc);
278                         continue;
279                 }
280
281                 if (strcmp(type, "voltage-sensor") == 0) {
282                         name = "cpu-voltage";
283                         shift = 4;
284                         vsens[core] = index;
285                 } else if (strcmp(type, "current-sensor") == 0) {
286                         name = "cpu-current";
287                         shift = 8;
288                         isens[core] = index;
289                 } else if (strcmp(type, "temp-sensor") == 0) {
290                         name = "cpu-temp";
291                         shift = 10;
292                 } else
293                         continue;       /* hmmm shouldn't happen */
294
295                 /* the +16 is enough for "cpu-voltage-n" */
296                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
297                 if (sens == NULL) {
298                         printk(KERN_ERR "wf_sat_create: couldn't create "
299                                "%s sensor %d (no memory)\n", name, cpu);
300                         continue;
301                 }
302                 sens->index = index;
303                 sens->index2 = -1;
304                 sens->shift = shift;
305                 sens->sat = sat;
306                 atomic_inc(&sat->refcnt);
307                 sens->sens.ops = &wf_sat_ops;
308                 sens->sens.name = (char *) (sens + 1);
309                 snprintf(sens->sens.name, 16, "%s-%d", name, cpu);
310
311                 if (wf_register_sensor(&sens->sens)) {
312                         atomic_dec(&sat->refcnt);
313                         kfree(sens);
314                 }
315         }
316
317         /* make the power sensors */
318         for (core = 0; core < 2; ++core) {
319                 if (vsens[core] < 0 || isens[core] < 0)
320                         continue;
321                 cpu = 2 * sat->nr + core;
322                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
323                 if (sens == NULL) {
324                         printk(KERN_ERR "wf_sat_create: couldn't create power "
325                                "sensor %d (no memory)\n", cpu);
326                         continue;
327                 }
328                 sens->index = vsens[core];
329                 sens->index2 = isens[core];
330                 sens->shift = 0;
331                 sens->sat = sat;
332                 atomic_inc(&sat->refcnt);
333                 sens->sens.ops = &wf_sat_ops;
334                 sens->sens.name = (char *) (sens + 1);
335                 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu);
336
337                 if (wf_register_sensor(&sens->sens)) {
338                         atomic_dec(&sat->refcnt);
339                         kfree(sens);
340                 }
341         }
342
343         if (sat->nr >= 0)
344                 sats[sat->nr] = sat;
345
346         return;
347
348  fail:
349         kfree(sat);
350 }
351
352 static int wf_sat_attach(struct i2c_adapter *adapter)
353 {
354         struct device_node *busnode, *dev = NULL;
355         struct pmac_i2c_bus *bus;
356
357         bus = pmac_i2c_adapter_to_bus(adapter);
358         if (bus == NULL)
359                 return -ENODEV;
360         busnode = pmac_i2c_get_bus_node(bus);
361
362         while ((dev = of_get_next_child(busnode, dev)) != NULL)
363                 if (of_device_is_compatible(dev, "smu-sat"))
364                         wf_sat_create(adapter, dev);
365         return 0;
366 }
367
368 static int wf_sat_detach(struct i2c_client *client)
369 {
370         struct wf_sat *sat = i2c_to_sat(client);
371
372         /* XXX TODO */
373
374         sat->i2c.adapter = NULL;
375         return 0;
376 }
377
378 static int __init sat_sensors_init(void)
379 {
380         return i2c_add_driver(&wf_sat_driver);
381 }
382
383 static void __exit sat_sensors_exit(void)
384 {
385         i2c_del_driver(&wf_sat_driver);
386 }
387
388 module_init(sat_sensors_init);
389 /*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */
390
391 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
392 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
393 MODULE_LICENSE("GPL");