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