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 void wf_sat_create(struct i2c_adapter *adapter, struct device_node *dev) 198 { 199 struct i2c_board_info info; 200 struct i2c_client *client; 201 const u32 *reg; 202 u8 addr; 203 204 reg = of_get_property(dev, "reg", NULL); 205 if (reg == NULL) 206 return; 207 addr = *reg; 208 DBG(KERN_DEBUG "wf_sat: creating sat at address %x\n", addr); 209 210 memset(&info, 0, sizeof(struct i2c_board_info)); 211 info.addr = (addr >> 1) & 0x7f; 212 info.platform_data = dev; 213 strlcpy(info.type, "wf_sat", I2C_NAME_SIZE); 214 215 client = i2c_new_device(adapter, &info); 216 if (client == NULL) { 217 printk(KERN_ERR "windfarm: failed to attach smu-sat to i2c\n"); 218 return; 219 } 220 221 /* 222 * Let i2c-core delete that device on driver removal. 223 * This is safe because i2c-core holds the core_lock mutex for us. 224 */ 225 list_add_tail(&client->detected, &client->driver->clients); 226 } 227 228 static int wf_sat_probe(struct i2c_client *client, 229 const struct i2c_device_id *id) 230 { 231 struct device_node *dev = client->dev.platform_data; 232 struct wf_sat *sat; 233 struct wf_sat_sensor *sens; 234 const u32 *reg; 235 const char *loc, *type; 236 u8 chip, core; 237 struct device_node *child; 238 int shift, cpu, index; 239 char *name; 240 int vsens[2], isens[2]; 241 242 sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL); 243 if (sat == NULL) 244 return -ENOMEM; 245 sat->nr = -1; 246 sat->node = of_node_get(dev); 247 atomic_set(&sat->refcnt, 0); 248 mutex_init(&sat->mutex); 249 sat->i2c = client; 250 i2c_set_clientdata(client, sat); 251 252 vsens[0] = vsens[1] = -1; 253 isens[0] = isens[1] = -1; 254 child = NULL; 255 while ((child = of_get_next_child(dev, child)) != NULL) { 256 reg = of_get_property(child, "reg", NULL); 257 type = of_get_property(child, "device_type", NULL); 258 loc = of_get_property(child, "location", NULL); 259 if (reg == NULL || loc == NULL) 260 continue; 261 262 /* the cooked sensors are between 0x30 and 0x37 */ 263 if (*reg < 0x30 || *reg > 0x37) 264 continue; 265 index = *reg - 0x30; 266 267 /* expect location to be CPU [AB][01] ... */ 268 if (strncmp(loc, "CPU ", 4) != 0) 269 continue; 270 chip = loc[4] - 'A'; 271 core = loc[5] - '0'; 272 if (chip > 1 || core > 1) { 273 printk(KERN_ERR "wf_sat_create: don't understand " 274 "location %s for %s\n", loc, child->full_name); 275 continue; 276 } 277 cpu = 2 * chip + core; 278 if (sat->nr < 0) 279 sat->nr = chip; 280 else if (sat->nr != chip) { 281 printk(KERN_ERR "wf_sat_create: can't cope with " 282 "multiple CPU chips on one SAT (%s)\n", loc); 283 continue; 284 } 285 286 if (strcmp(type, "voltage-sensor") == 0) { 287 name = "cpu-voltage"; 288 shift = 4; 289 vsens[core] = index; 290 } else if (strcmp(type, "current-sensor") == 0) { 291 name = "cpu-current"; 292 shift = 8; 293 isens[core] = index; 294 } else if (strcmp(type, "temp-sensor") == 0) { 295 name = "cpu-temp"; 296 shift = 10; 297 } else 298 continue; /* hmmm shouldn't happen */ 299 300 /* the +16 is enough for "cpu-voltage-n" */ 301 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 302 if (sens == NULL) { 303 printk(KERN_ERR "wf_sat_create: couldn't create " 304 "%s sensor %d (no memory)\n", name, cpu); 305 continue; 306 } 307 sens->index = index; 308 sens->index2 = -1; 309 sens->shift = shift; 310 sens->sat = sat; 311 atomic_inc(&sat->refcnt); 312 sens->sens.ops = &wf_sat_ops; 313 sens->sens.name = (char *) (sens + 1); 314 snprintf(sens->sens.name, 16, "%s-%d", name, cpu); 315 316 if (wf_register_sensor(&sens->sens)) { 317 atomic_dec(&sat->refcnt); 318 kfree(sens); 319 } 320 } 321 322 /* make the power sensors */ 323 for (core = 0; core < 2; ++core) { 324 if (vsens[core] < 0 || isens[core] < 0) 325 continue; 326 cpu = 2 * sat->nr + core; 327 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 328 if (sens == NULL) { 329 printk(KERN_ERR "wf_sat_create: couldn't create power " 330 "sensor %d (no memory)\n", cpu); 331 continue; 332 } 333 sens->index = vsens[core]; 334 sens->index2 = isens[core]; 335 sens->shift = 0; 336 sens->sat = sat; 337 atomic_inc(&sat->refcnt); 338 sens->sens.ops = &wf_sat_ops; 339 sens->sens.name = (char *) (sens + 1); 340 snprintf(sens->sens.name, 16, "cpu-power-%d", cpu); 341 342 if (wf_register_sensor(&sens->sens)) { 343 atomic_dec(&sat->refcnt); 344 kfree(sens); 345 } 346 } 347 348 if (sat->nr >= 0) 349 sats[sat->nr] = sat; 350 351 return 0; 352 } 353 354 static int wf_sat_attach(struct i2c_adapter *adapter) 355 { 356 struct device_node *busnode, *dev = NULL; 357 struct pmac_i2c_bus *bus; 358 359 bus = pmac_i2c_adapter_to_bus(adapter); 360 if (bus == NULL) 361 return -ENODEV; 362 busnode = pmac_i2c_get_bus_node(bus); 363 364 while ((dev = of_get_next_child(busnode, dev)) != NULL) 365 if (of_device_is_compatible(dev, "smu-sat")) 366 wf_sat_create(adapter, dev); 367 return 0; 368 } 369 370 static int wf_sat_remove(struct i2c_client *client) 371 { 372 struct wf_sat *sat = i2c_get_clientdata(client); 373 374 /* XXX TODO */ 375 376 sat->i2c = NULL; 377 i2c_set_clientdata(client, NULL); 378 return 0; 379 } 380 381 static const struct i2c_device_id wf_sat_id[] = { 382 { "wf_sat", 0 }, 383 { } 384 }; 385 386 static 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 }; 395 396 static int __init sat_sensors_init(void) 397 { 398 return i2c_add_driver(&wf_sat_driver); 399 } 400 401 #if 0 /* uncomment when module_exit() below is uncommented */ 402 static void __exit sat_sensors_exit(void) 403 { 404 i2c_del_driver(&wf_sat_driver); 405 } 406 #endif 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"); 414