2 * Windfarm PowerMac thermal control. SMU "satellite" controller sensors.
4 * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
6 * Released under the terms of the GNU GPL v2.
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/i2c-dev.h>
17 #include <asm/semaphore.h>
20 #include <asm/pmac_low_i2c.h>
29 #define DBG(args...) printk(args)
31 #define DBG(args...) do { } while(0)
34 /* If the cache is older than 800ms we'll refetch it */
35 #define MAX_AGE msecs_to_jiffies(800)
40 struct semaphore mutex;
41 unsigned long last_read; /* jiffies when cache last updated */
43 struct i2c_client i2c;
44 struct device_node *node;
47 static struct wf_sat *sats[2];
49 struct wf_sat_sensor {
51 int index2; /* used for power sensors */
54 struct wf_sensor sens;
57 #define wf_to_sat(c) container_of(c, struct wf_sat_sensor, sens)
58 #define i2c_to_sat(c) container_of(c, struct wf_sat, i2c)
60 static int wf_sat_attach(struct i2c_adapter *adapter);
61 static int wf_sat_detach(struct i2c_client *client);
63 static struct i2c_driver wf_sat_driver = {
67 .attach_adapter = wf_sat_attach,
68 .detach_client = wf_sat_detach,
72 * XXX i2c_smbus_read_i2c_block_data doesn't pass the requested
73 * length down to the low-level driver, so we use this, which
74 * works well enough with the SMU i2c driver code...
76 static int sat_read_block(struct i2c_client *client, u8 command,
79 union i2c_smbus_data data;
83 err = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
84 I2C_SMBUS_READ, command, I2C_SMBUS_I2C_BLOCK_DATA,
87 memcpy(values, data.block, len);
91 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
100 /* TODO: Add the resulting partition to the device-tree */
102 if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
105 err = i2c_smbus_write_word_data(&sat->i2c, 8, id << 8);
107 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
111 len = i2c_smbus_read_word_data(&sat->i2c, 9);
113 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
117 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
121 len = le16_to_cpu(len);
122 len = (len + 3) & ~3;
123 buf = kmalloc(len, GFP_KERNEL);
127 for (i = 0; i < len; i += 4) {
128 err = sat_read_block(&sat->i2c, 0xa, data, 4);
130 printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
140 DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id);
141 for (i = 0; i < len; ++i)
148 return (struct smu_sdbp_header *) buf;
154 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);
156 /* refresh the cache */
157 static int wf_sat_read_cache(struct wf_sat *sat)
161 err = sat_read_block(&sat->i2c, 0x3f, sat->cache, 16);
164 sat->last_read = jiffies;
168 DBG(KERN_DEBUG "wf_sat_get: data is");
169 for (i = 0; i < 16; ++i)
170 DBG(" %.2x", sat->cache[i]);
177 static int wf_sat_get(struct wf_sensor *sr, s32 *value)
179 struct wf_sat_sensor *sens = wf_to_sat(sr);
180 struct wf_sat *sat = sens->sat;
184 if (sat->i2c.adapter == NULL)
188 if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
189 err = wf_sat_read_cache(sat);
195 val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
196 if (sens->index2 >= 0) {
197 i = sens->index2 * 2;
198 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
199 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
210 static void wf_sat_release(struct wf_sensor *sr)
212 struct wf_sat_sensor *sens = wf_to_sat(sr);
213 struct wf_sat *sat = sens->sat;
215 if (atomic_dec_and_test(&sat->refcnt)) {
216 if (sat->i2c.adapter) {
217 i2c_detach_client(&sat->i2c);
218 sat->i2c.adapter = NULL;
221 sats[sat->nr] = NULL;
227 static struct wf_sensor_ops wf_sat_ops = {
228 .get_value = wf_sat_get,
229 .release = wf_sat_release,
230 .owner = THIS_MODULE,
233 static void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev)
236 struct wf_sat_sensor *sens;
240 struct device_node *child;
241 int shift, cpu, index;
243 int vsens[2], isens[2];
245 reg = (u32 *) get_property(dev, "reg", NULL);
249 DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr);
251 sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
255 sat->node = of_node_get(dev);
256 atomic_set(&sat->refcnt, 0);
257 init_MUTEX(&sat->mutex);
258 sat->i2c.addr = (addr >> 1) & 0x7f;
259 sat->i2c.adapter = adapter;
260 sat->i2c.driver = &wf_sat_driver;
261 strncpy(sat->i2c.name, "smu-sat", I2C_NAME_SIZE-1);
263 if (i2c_attach_client(&sat->i2c)) {
264 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n");
268 vsens[0] = vsens[1] = -1;
269 isens[0] = isens[1] = -1;
271 while ((child = of_get_next_child(dev, child)) != NULL) {
272 reg = (u32 *) get_property(child, "reg", NULL);
273 type = get_property(child, "device_type", NULL);
274 loc = get_property(child, "location", NULL);
275 if (reg == NULL || loc == NULL)
278 /* the cooked sensors are between 0x30 and 0x37 */
279 if (*reg < 0x30 || *reg > 0x37)
283 /* expect location to be CPU [AB][01] ... */
284 if (strncmp(loc, "CPU ", 4) != 0)
288 if (chip > 1 || core > 1) {
289 printk(KERN_ERR "wf_sat_create: don't understand "
290 "location %s for %s\n", loc, child->full_name);
293 cpu = 2 * chip + core;
296 else if (sat->nr != chip) {
297 printk(KERN_ERR "wf_sat_create: can't cope with "
298 "multiple CPU chips on one SAT (%s)\n", loc);
302 if (strcmp(type, "voltage-sensor") == 0) {
303 name = "cpu-voltage";
306 } else if (strcmp(type, "current-sensor") == 0) {
307 name = "cpu-current";
310 } else if (strcmp(type, "temp-sensor") == 0) {
314 continue; /* hmmm shouldn't happen */
316 /* the +16 is enough for "cpu-voltage-n" */
317 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
319 printk(KERN_ERR "wf_sat_create: couldn't create "
320 "%s sensor %d (no memory)\n", name, cpu);
327 atomic_inc(&sat->refcnt);
328 sens->sens.ops = &wf_sat_ops;
329 sens->sens.name = (char *) (sens + 1);
330 snprintf(sens->sens.name, 16, "%s-%d", name, cpu);
332 if (wf_register_sensor(&sens->sens)) {
333 atomic_dec(&sat->refcnt);
338 /* make the power sensors */
339 for (core = 0; core < 2; ++core) {
340 if (vsens[core] < 0 || isens[core] < 0)
342 cpu = 2 * sat->nr + core;
343 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
345 printk(KERN_ERR "wf_sat_create: couldn't create power "
346 "sensor %d (no memory)\n", cpu);
349 sens->index = vsens[core];
350 sens->index2 = isens[core];
353 atomic_inc(&sat->refcnt);
354 sens->sens.ops = &wf_sat_ops;
355 sens->sens.name = (char *) (sens + 1);
356 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu);
358 if (wf_register_sensor(&sens->sens)) {
359 atomic_dec(&sat->refcnt);
373 static int wf_sat_attach(struct i2c_adapter *adapter)
375 struct device_node *busnode, *dev = NULL;
376 struct pmac_i2c_bus *bus;
378 bus = pmac_i2c_adapter_to_bus(adapter);
381 busnode = pmac_i2c_get_bus_node(bus);
383 while ((dev = of_get_next_child(busnode, dev)) != NULL)
384 if (device_is_compatible(dev, "smu-sat"))
385 wf_sat_create(adapter, dev);
389 static int wf_sat_detach(struct i2c_client *client)
391 struct wf_sat *sat = i2c_to_sat(client);
395 sat->i2c.adapter = NULL;
399 static int __init sat_sensors_init(void)
403 err = i2c_add_driver(&wf_sat_driver);
409 static void __exit sat_sensors_exit(void)
411 i2c_del_driver(&wf_sat_driver);
414 module_init(sat_sensors_init);
415 /*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */
417 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
418 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
419 MODULE_LICENSE("GPL");