backlight: Separate backlight properties from backlight ops pointers
[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 /*
71  * XXX i2c_smbus_read_i2c_block_data doesn't pass the requested
72  * length down to the low-level driver, so we use this, which
73  * works well enough with the SMU i2c driver code...
74  */
75 static int sat_read_block(struct i2c_client *client, u8 command,
76                           u8 *values, int len)
77 {
78         union i2c_smbus_data data;
79         int err;
80
81         data.block[0] = len;
82         err = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
83                              I2C_SMBUS_READ, command, I2C_SMBUS_I2C_BLOCK_DATA,
84                              &data);
85         if (!err)
86                 memcpy(values, data.block, len);
87         return err;
88 }
89
90 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
91                                                   unsigned int *size)
92 {
93         struct wf_sat *sat;
94         int err;
95         unsigned int i, len;
96         u8 *buf;
97         u8 data[4];
98
99         /* TODO: Add the resulting partition to the device-tree */
100
101         if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
102                 return NULL;
103
104         err = i2c_smbus_write_word_data(&sat->i2c, 8, id << 8);
105         if (err) {
106                 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
107                 return NULL;
108         }
109
110         len = i2c_smbus_read_word_data(&sat->i2c, 9);
111         if (len < 0) {
112                 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
113                 return NULL;
114         }
115         if (len == 0) {
116                 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
117                 return NULL;
118         }
119
120         len = le16_to_cpu(len);
121         len = (len + 3) & ~3;
122         buf = kmalloc(len, GFP_KERNEL);
123         if (buf == NULL)
124                 return NULL;
125
126         for (i = 0; i < len; i += 4) {
127                 err = sat_read_block(&sat->i2c, 0xa, data, 4);
128                 if (err) {
129                         printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
130                                err);
131                         goto fail;
132                 }
133                 buf[i] = data[1];
134                 buf[i+1] = data[0];
135                 buf[i+2] = data[3];
136                 buf[i+3] = data[2];
137         }
138 #ifdef DEBUG
139         DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id);
140         for (i = 0; i < len; ++i)
141                 DBG(" %x", buf[i]);
142         DBG("\n");
143 #endif
144
145         if (size)
146                 *size = len;
147         return (struct smu_sdbp_header *) buf;
148
149  fail:
150         kfree(buf);
151         return NULL;
152 }
153 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);
154
155 /* refresh the cache */
156 static int wf_sat_read_cache(struct wf_sat *sat)
157 {
158         int err;
159
160         err = sat_read_block(&sat->i2c, 0x3f, sat->cache, 16);
161         if (err)
162                 return err;
163         sat->last_read = jiffies;
164 #ifdef LOTSA_DEBUG
165         {
166                 int i;
167                 DBG(KERN_DEBUG "wf_sat_get: data is");
168                 for (i = 0; i < 16; ++i)
169                         DBG(" %.2x", sat->cache[i]);
170                 DBG("\n");
171         }
172 #endif
173         return 0;
174 }
175
176 static int wf_sat_get(struct wf_sensor *sr, s32 *value)
177 {
178         struct wf_sat_sensor *sens = wf_to_sat(sr);
179         struct wf_sat *sat = sens->sat;
180         int i, err;
181         s32 val;
182
183         if (sat->i2c.adapter == NULL)
184                 return -ENODEV;
185
186         down(&sat->mutex);
187         if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
188                 err = wf_sat_read_cache(sat);
189                 if (err)
190                         goto fail;
191         }
192
193         i = sens->index * 2;
194         val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
195         if (sens->index2 >= 0) {
196                 i = sens->index2 * 2;
197                 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
198                 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
199         }
200
201         *value = val;
202         err = 0;
203
204  fail:
205         up(&sat->mutex);
206         return err;
207 }
208
209 static void wf_sat_release(struct wf_sensor *sr)
210 {
211         struct wf_sat_sensor *sens = wf_to_sat(sr);
212         struct wf_sat *sat = sens->sat;
213
214         if (atomic_dec_and_test(&sat->refcnt)) {
215                 if (sat->i2c.adapter) {
216                         i2c_detach_client(&sat->i2c);
217                         sat->i2c.adapter = NULL;
218                 }
219                 if (sat->nr >= 0)
220                         sats[sat->nr] = NULL;
221                 kfree(sat);
222         }
223         kfree(sens);
224 }
225
226 static struct wf_sensor_ops wf_sat_ops = {
227         .get_value      = wf_sat_get,
228         .release        = wf_sat_release,
229         .owner          = THIS_MODULE,
230 };
231
232 static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev)
233 {
234         struct wf_sat *sat;
235         struct wf_sat_sensor *sens;
236         const u32 *reg;
237         const char *loc, *type;
238         u8 addr, chip, core;
239         struct device_node *child;
240         int shift, cpu, index;
241         char *name;
242         int vsens[2], isens[2];
243
244         reg = get_property(dev, "reg", NULL);
245         if (reg == NULL)
246                 return;
247         addr = *reg;
248         DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr);
249
250         sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
251         if (sat == NULL)
252                 return;
253         sat->nr = -1;
254         sat->node = of_node_get(dev);
255         atomic_set(&sat->refcnt, 0);
256         init_MUTEX(&sat->mutex);
257         sat->i2c.addr = (addr >> 1) & 0x7f;
258         sat->i2c.adapter = adapter;
259         sat->i2c.driver = &wf_sat_driver;
260         strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1);
261
262         if (i2c_attach_client(&sat->i2c)) {
263                 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n");
264                 goto fail;
265         }
266
267         vsens[0] = vsens[1] = -1;
268         isens[0] = isens[1] = -1;
269         child = NULL;
270         while ((child = of_get_next_child(dev, child)) != NULL) {
271                 reg = get_property(child, "reg", NULL);
272                 type = get_property(child, "device_type", NULL);
273                 loc = get_property(child, "location", NULL);
274                 if (reg == NULL || loc == NULL)
275                         continue;
276
277                 /* the cooked sensors are between 0x30 and 0x37 */
278                 if (*reg < 0x30 || *reg > 0x37)
279                         continue;
280                 index = *reg - 0x30;
281
282                 /* expect location to be CPU [AB][01] ... */
283                 if (strncmp(loc, "CPU ", 4) != 0)
284                         continue;
285                 chip = loc[4] - 'A';
286                 core = loc[5] - '0';
287                 if (chip > 1 || core > 1) {
288                         printk(KERN_ERR "wf_sat_create: don't understand "
289                                "location %s for %s\n", loc, child->full_name);
290                         continue;
291                 }
292                 cpu = 2 * chip + core;
293                 if (sat->nr < 0)
294                         sat->nr = chip;
295                 else if (sat->nr != chip) {
296                         printk(KERN_ERR "wf_sat_create: can't cope with "
297                                "multiple CPU chips on one SAT (%s)\n", loc);
298                         continue;
299                 }
300
301                 if (strcmp(type, "voltage-sensor") == 0) {
302                         name = "cpu-voltage";
303                         shift = 4;
304                         vsens[core] = index;
305                 } else if (strcmp(type, "current-sensor") == 0) {
306                         name = "cpu-current";
307                         shift = 8;
308                         isens[core] = index;
309                 } else if (strcmp(type, "temp-sensor") == 0) {
310                         name = "cpu-temp";
311                         shift = 10;
312                 } else
313                         continue;       /* hmmm shouldn't happen */
314
315                 /* the +16 is enough for "cpu-voltage-n" */
316                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
317                 if (sens == NULL) {
318                         printk(KERN_ERR "wf_sat_create: couldn't create "
319                                "%s sensor %d (no memory)\n", name, cpu);
320                         continue;
321                 }
322                 sens->index = index;
323                 sens->index2 = -1;
324                 sens->shift = shift;
325                 sens->sat = sat;
326                 atomic_inc(&sat->refcnt);
327                 sens->sens.ops = &wf_sat_ops;
328                 sens->sens.name = (char *) (sens + 1);
329                 snprintf(sens->sens.name, 16, "%s-%d", name, cpu);
330
331                 if (wf_register_sensor(&sens->sens)) {
332                         atomic_dec(&sat->refcnt);
333                         kfree(sens);
334                 }
335         }
336
337         /* make the power sensors */
338         for (core = 0; core < 2; ++core) {
339                 if (vsens[core] < 0 || isens[core] < 0)
340                         continue;
341                 cpu = 2 * sat->nr + core;
342                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
343                 if (sens == NULL) {
344                         printk(KERN_ERR "wf_sat_create: couldn't create power "
345                                "sensor %d (no memory)\n", cpu);
346                         continue;
347                 }
348                 sens->index = vsens[core];
349                 sens->index2 = isens[core];
350                 sens->shift = 0;
351                 sens->sat = sat;
352                 atomic_inc(&sat->refcnt);
353                 sens->sens.ops = &wf_sat_ops;
354                 sens->sens.name = (char *) (sens + 1);
355                 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu);
356
357                 if (wf_register_sensor(&sens->sens)) {
358                         atomic_dec(&sat->refcnt);
359                         kfree(sens);
360                 }
361         }
362
363         if (sat->nr >= 0)
364                 sats[sat->nr] = sat;
365
366         return;
367
368  fail:
369         kfree(sat);
370 }
371
372 static int wf_sat_attach(struct i2c_adapter *adapter)
373 {
374         struct device_node *busnode, *dev = NULL;
375         struct pmac_i2c_bus *bus;
376
377         bus = pmac_i2c_adapter_to_bus(adapter);
378         if (bus == NULL)
379                 return -ENODEV;
380         busnode = pmac_i2c_get_bus_node(bus);
381
382         while ((dev = of_get_next_child(busnode, dev)) != NULL)
383                 if (device_is_compatible(dev, "smu-sat"))
384                         wf_sat_create(adapter, dev);
385         return 0;
386 }
387
388 static int wf_sat_detach(struct i2c_client *client)
389 {
390         struct wf_sat *sat = i2c_to_sat(client);
391
392         /* XXX TODO */
393
394         sat->i2c.adapter = NULL;
395         return 0;
396 }
397
398 static int __init sat_sensors_init(void)
399 {
400         return i2c_add_driver(&wf_sat_driver);
401 }
402
403 static void __exit sat_sensors_exit(void)
404 {
405         i2c_del_driver(&wf_sat_driver);
406 }
407
408 module_init(sat_sensors_init);
409 /*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */
410
411 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
412 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
413 MODULE_LICENSE("GPL");