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 36struct 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 46static struct wf_sat *sats[2]; 47 48struct 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 58struct 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} 122EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition); 123 124/* refresh the cache */ 125static 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 145static 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 178static 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 191static struct wf_sensor_ops wf_sat_ops = { 192 .get_value = wf_sat_get, 193 .release = wf_sat_release, 194 .owner = THIS_MODULE, 195}; 196 197static struct i2c_driver wf_sat_driver; 198 199static 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 230static 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 356static 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 372static int wf_sat_remove(struct i2c_client *client) 373{ 374 struct wf_sat *sat = i2c_get_clientdata(client); 375 376 377 sat->i2c = NULL; 378 return 0; 379} 380 381static const struct i2c_device_id wf_sat_id[] = { 382 { "wf_sat", 0 }, 383 { } 384}; 385 386static struct i2c_driver wf_sat_driver = { 387 .driver = { 388 .name = "wf_smu_sat", 389 }, 390 .attach_adapter = wf_sat_attach, 391 .probe = wf_sat_probe, 392 .remove = wf_sat_remove, 393 .id_table = wf_sat_id, 394}; 395 396static int __init sat_sensors_init(void) 397{ 398 return i2c_add_driver(&wf_sat_driver); 399} 400 401 402module_init(sat_sensors_init); 403/*module_exit(sat_sensors_exit); Uncomment when cleanup is implemented */ 404 405MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); 406MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control"); 407MODULE_LICENSE("GPL"); 408