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