Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[pandora-kernel.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 <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
58 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
59                                                   unsigned int *size)
60 {
61         struct wf_sat *sat;
62         int err;
63         unsigned int i, len;
64         u8 *buf;
65         u8 data[4];
66
67         /* TODO: Add the resulting partition to the device-tree */
68
69         if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
70                 return NULL;
71
72         err = i2c_smbus_write_word_data(sat->i2c, 8, id << 8);
73         if (err) {
74                 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
75                 return NULL;
76         }
77
78         err = i2c_smbus_read_word_data(sat->i2c, 9);
79         if (err < 0) {
80                 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
81                 return NULL;
82         }
83         len = err;
84         if (len == 0) {
85                 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
86                 return NULL;
87         }
88
89         len = le16_to_cpu(len);
90         len = (len + 3) & ~3;
91         buf = kmalloc(len, GFP_KERNEL);
92         if (buf == NULL)
93                 return NULL;
94
95         for (i = 0; i < len; i += 4) {
96                 err = i2c_smbus_read_i2c_block_data(sat->i2c, 0xa, 4, data);
97                 if (err < 0) {
98                         printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
99                                err);
100                         goto fail;
101                 }
102                 buf[i] = data[1];
103                 buf[i+1] = data[0];
104                 buf[i+2] = data[3];
105                 buf[i+3] = data[2];
106         }
107 #ifdef DEBUG
108         DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id);
109         for (i = 0; i < len; ++i)
110                 DBG(" %x", buf[i]);
111         DBG("\n");
112 #endif
113
114         if (size)
115                 *size = len;
116         return (struct smu_sdbp_header *) buf;
117
118  fail:
119         kfree(buf);
120         return NULL;
121 }
122 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);
123
124 /* refresh the cache */
125 static int wf_sat_read_cache(struct wf_sat *sat)
126 {
127         int err;
128
129         err = i2c_smbus_read_i2c_block_data(sat->i2c, 0x3f, 16, sat->cache);
130         if (err < 0)
131                 return err;
132         sat->last_read = jiffies;
133 #ifdef LOTSA_DEBUG
134         {
135                 int i;
136                 DBG(KERN_DEBUG "wf_sat_get: data is");
137                 for (i = 0; i < 16; ++i)
138                         DBG(" %.2x", sat->cache[i]);
139                 DBG("\n");
140         }
141 #endif
142         return 0;
143 }
144
145 static int wf_sat_get(struct wf_sensor *sr, s32 *value)
146 {
147         struct wf_sat_sensor *sens = wf_to_sat(sr);
148         struct wf_sat *sat = sens->sat;
149         int i, err;
150         s32 val;
151
152         if (sat->i2c == NULL)
153                 return -ENODEV;
154
155         mutex_lock(&sat->mutex);
156         if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
157                 err = wf_sat_read_cache(sat);
158                 if (err)
159                         goto fail;
160         }
161
162         i = sens->index * 2;
163         val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
164         if (sens->index2 >= 0) {
165                 i = sens->index2 * 2;
166                 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
167                 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
168         }
169
170         *value = val;
171         err = 0;
172
173  fail:
174         mutex_unlock(&sat->mutex);
175         return err;
176 }
177
178 static void wf_sat_release(struct wf_sensor *sr)
179 {
180         struct wf_sat_sensor *sens = wf_to_sat(sr);
181         struct wf_sat *sat = sens->sat;
182
183         if (atomic_dec_and_test(&sat->refcnt)) {
184                 if (sat->nr >= 0)
185                         sats[sat->nr] = NULL;
186                 kfree(sat);
187         }
188         kfree(sens);
189 }
190
191 static struct wf_sensor_ops wf_sat_ops = {
192         .get_value      = wf_sat_get,
193         .release        = wf_sat_release,
194         .owner          = THIS_MODULE,
195 };
196
197 static struct i2c_driver wf_sat_driver;
198
199 static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev)
200 {
201         struct i2c_board_info info;
202         struct i2c_client *client;
203         const u32 *reg;
204         u8 addr;
205
206         reg = of_get_property(dev, "reg", NULL);
207         if (reg == NULL)
208                 return;
209         addr = *reg;
210         DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr);
211
212         memset(&info, 0, sizeof(struct i2c_board_info));
213         info.addr = (addr >> 1) & 0x7f;
214         info.platform_data = dev;
215         strlcpy(info.type, "wf_sat", I2C_NAME_SIZE);
216
217         client = i2c_new_device(adapter, &info);
218         if (client == NULL) {
219                 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n");
220                 return;
221         }
222
223         /*
224          * Let i2c-core delete that device on driver removal.
225          * This is safe because i2c-core holds the core_lock mutex for us.
226          */
227         list_add_tail(&client->detected, &wf_sat_driver.clients);
228 }
229
230 static int wf_sat_probe(struct i2c_client *client,
231                         const struct i2c_device_id *id)
232 {
233         struct device_node *dev = client->dev.platform_data;
234         struct wf_sat *sat;
235         struct wf_sat_sensor *sens;
236         const u32 *reg;
237         const char *loc, *type;
238         u8 chip, core;
239         struct device_node *child;
240         int shift, cpu, index;
241         char *name;
242         int vsens[2], isens[2];
243
244         sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
245         if (sat == NULL)
246                 return -ENOMEM;
247         sat->nr = -1;
248         sat->node = of_node_get(dev);
249         atomic_set(&sat->refcnt, 0);
250         mutex_init(&sat->mutex);
251         sat->i2c = client;
252         i2c_set_clientdata(client, sat);
253
254         vsens[0] = vsens[1] = -1;
255         isens[0] = isens[1] = -1;
256         child = NULL;
257         while ((child = of_get_next_child(dev, child)) != NULL) {
258                 reg = of_get_property(child, "reg", NULL);
259                 type = of_get_property(child, "device_type", NULL);
260                 loc = of_get_property(child, "location", NULL);
261                 if (reg == NULL || loc == NULL)
262                         continue;
263
264                 /* the cooked sensors are between 0x30 and 0x37 */
265                 if (*reg < 0x30 || *reg > 0x37)
266                         continue;
267                 index = *reg - 0x30;
268
269                 /* expect location to be CPU [AB][01] ... */
270                 if (strncmp(loc, "CPU ", 4) != 0)
271                         continue;
272                 chip = loc[4] - 'A';
273                 core = loc[5] - '0';
274                 if (chip > 1 || core > 1) {
275                         printk(KERN_ERR "wf_sat_create: don't understand "
276                                "location %s for %s\n", loc, child->full_name);
277                         continue;
278                 }
279                 cpu = 2 * chip + core;
280                 if (sat->nr < 0)
281                         sat->nr = chip;
282                 else if (sat->nr != chip) {
283                         printk(KERN_ERR "wf_sat_create: can't cope with "
284                                "multiple CPU chips on one SAT (%s)\n", loc);
285                         continue;
286                 }
287
288                 if (strcmp(type, "voltage-sensor") == 0) {
289                         name = "cpu-voltage";
290                         shift = 4;
291                         vsens[core] = index;
292                 } else if (strcmp(type, "current-sensor") == 0) {
293                         name = "cpu-current";
294                         shift = 8;
295                         isens[core] = index;
296                 } else if (strcmp(type, "temp-sensor") == 0) {
297                         name = "cpu-temp";
298                         shift = 10;
299                 } else
300                         continue;       /* hmmm shouldn't happen */
301
302                 /* the +16 is enough for "cpu-voltage-n" */
303                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
304                 if (sens == NULL) {
305                         printk(KERN_ERR "wf_sat_create: couldn't create "
306                                "%s sensor %d (no memory)\n", name, cpu);
307                         continue;
308                 }
309                 sens->index = index;
310                 sens->index2 = -1;
311                 sens->shift = shift;
312                 sens->sat = sat;
313                 atomic_inc(&sat->refcnt);
314                 sens->sens.ops = &wf_sat_ops;
315                 sens->sens.name = (char *) (sens + 1);
316                 snprintf(sens->sens.name, 16, "%s-%d", name, cpu);
317
318                 if (wf_register_sensor(&sens->sens)) {
319                         atomic_dec(&sat->refcnt);
320                         kfree(sens);
321                 }
322         }
323
324         /* make the power sensors */
325         for (core = 0; core < 2; ++core) {
326                 if (vsens[core] < 0 || isens[core] < 0)
327                         continue;
328                 cpu = 2 * sat->nr + core;
329                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
330                 if (sens == NULL) {
331                         printk(KERN_ERR "wf_sat_create: couldn't create power "
332                                "sensor %d (no memory)\n", cpu);
333                         continue;
334                 }
335                 sens->index = vsens[core];
336                 sens->index2 = isens[core];
337                 sens->shift = 0;
338                 sens->sat = sat;
339                 atomic_inc(&sat->refcnt);
340                 sens->sens.ops = &wf_sat_ops;
341                 sens->sens.name = (char *) (sens + 1);
342                 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu);
343
344                 if (wf_register_sensor(&sens->sens)) {
345                         atomic_dec(&sat->refcnt);
346                         kfree(sens);
347                 }
348         }
349
350         if (sat->nr >= 0)
351                 sats[sat->nr] = sat;
352
353         return 0;
354 }
355
356 static int wf_sat_attach(struct i2c_adapter *adapter)
357 {
358         struct device_node *busnode, *dev = NULL;
359         struct pmac_i2c_bus *bus;
360
361         bus = pmac_i2c_adapter_to_bus(adapter);
362         if (bus == NULL)
363                 return -ENODEV;
364         busnode = pmac_i2c_get_bus_node(bus);
365
366         while ((dev = of_get_next_child(busnode, dev)) != NULL)
367                 if (of_device_is_compatible(dev, "smu-sat"))
368                         wf_sat_create(adapter, dev);
369         return 0;
370 }
371
372 static int wf_sat_remove(struct i2c_client *client)
373 {
374         struct wf_sat *sat = i2c_get_clientdata(client);
375
376         /* XXX TODO */
377
378         sat->i2c = NULL;
379         return 0;
380 }
381
382 static const struct i2c_device_id wf_sat_id[] = {
383         { "wf_sat", 0 },
384         { }
385 };
386
387 static struct i2c_driver wf_sat_driver = {
388         .driver = {
389                 .name           = "wf_smu_sat",
390         },
391         .attach_adapter = wf_sat_attach,
392         .probe          = wf_sat_probe,
393         .remove         = wf_sat_remove,
394         .id_table       = wf_sat_id,
395 };
396
397 static int __init sat_sensors_init(void)
398 {
399         return i2c_add_driver(&wf_sat_driver);
400 }
401
402 #if 0   /* uncomment when module_exit() below is uncommented */
403 static void __exit sat_sensors_exit(void)
404 {
405         i2c_del_driver(&wf_sat_driver);
406 }
407 #endif
408
409 module_init(sat_sensors_init);
410 /*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */
411
412 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
413 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
414 MODULE_LICENSE("GPL");