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 "1.0" 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 struct kref ref; 38 int nr; 39 struct mutex mutex; 40 unsigned long last_read; /* jiffies when cache last updated */ 41 u8 cache[16]; 42 struct list_head sensors; 43 struct i2c_client *i2c; 44 struct device_node *node; 45 }; 46 47 static struct wf_sat *sats[2]; 48 49 struct wf_sat_sensor { 50 struct list_head link; 51 int index; 52 int index2; /* used for power sensors */ 53 int shift; 54 struct wf_sat *sat; 55 struct wf_sensor sens; 56 }; 57 58 #define wf_to_sat(c) container_of(c, struct wf_sat_sensor, sens) 59 60 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id, 61 unsigned int *size) 62 { 63 struct wf_sat *sat; 64 int err; 65 unsigned int i, len; 66 u8 *buf; 67 u8 data[4]; 68 69 /* TODO: Add the resulting partition to the device-tree */ 70 71 if (sat_id > 1 || (sat = sats[sat_id]) == NULL) 72 return NULL; 73 74 err = i2c_smbus_write_word_data(sat->i2c, 8, id << 8); 75 if (err) { 76 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err); 77 return NULL; 78 } 79 80 err = i2c_smbus_read_word_data(sat->i2c, 9); 81 if (err < 0) { 82 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n"); 83 return NULL; 84 } 85 len = err; 86 if (len == 0) { 87 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id); 88 return NULL; 89 } 90 91 len = le16_to_cpu(len); 92 len = (len + 3) & ~3; 93 buf = kmalloc(len, GFP_KERNEL); 94 if (buf == NULL) 95 return NULL; 96 97 for (i = 0; i < len; i += 4) { 98 err = i2c_smbus_read_i2c_block_data(sat->i2c, 0xa, 4, data); 99 if (err < 0) { 100 printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n", 101 err); 102 goto fail; 103 } 104 buf[i] = data[1]; 105 buf[i+1] = data[0]; 106 buf[i+2] = data[3]; 107 buf[i+3] = data[2]; 108 } 109 #ifdef DEBUG 110 DBG(KERN_DEBUG "sat %d partition %x:", sat_id, id); 111 for (i = 0; i < len; ++i) 112 DBG(" %x", buf[i]); 113 DBG("\n"); 114 #endif 115 116 if (size) 117 *size = len; 118 return (struct smu_sdbp_header *) buf; 119 120 fail: 121 kfree(buf); 122 return NULL; 123 } 124 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition); 125 126 /* refresh the cache */ 127 static int wf_sat_read_cache(struct wf_sat *sat) 128 { 129 int err; 130 131 err = i2c_smbus_read_i2c_block_data(sat->i2c, 0x3f, 16, sat->cache); 132 if (err < 0) 133 return err; 134 sat->last_read = jiffies; 135 #ifdef LOTSA_DEBUG 136 { 137 int i; 138 DBG(KERN_DEBUG "wf_sat_get: data is"); 139 for (i = 0; i < 16; ++i) 140 DBG(" %.2x", sat->cache[i]); 141 DBG("\n"); 142 } 143 #endif 144 return 0; 145 } 146 147 static int wf_sat_sensor_get(struct wf_sensor *sr, s32 *value) 148 { 149 struct wf_sat_sensor *sens = wf_to_sat(sr); 150 struct wf_sat *sat = sens->sat; 151 int i, err; 152 s32 val; 153 154 if (sat->i2c == NULL) 155 return -ENODEV; 156 157 mutex_lock(&sat->mutex); 158 if (time_after(jiffies, (sat->last_read + MAX_AGE))) { 159 err = wf_sat_read_cache(sat); 160 if (err) 161 goto fail; 162 } 163 164 i = sens->index * 2; 165 val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift; 166 if (sens->index2 >= 0) { 167 i = sens->index2 * 2; 168 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */ 169 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4; 170 } 171 172 *value = val; 173 err = 0; 174 175 fail: 176 mutex_unlock(&sat->mutex); 177 return err; 178 } 179 180 static void wf_sat_release(struct kref *ref) 181 { 182 struct wf_sat *sat = container_of(ref, struct wf_sat, ref); 183 184 if (sat->nr >= 0) 185 sats[sat->nr] = NULL; 186 kfree(sat); 187 } 188 189 static void wf_sat_sensor_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 kfree(sens); 195 kref_put(&sat->ref, wf_sat_release); 196 } 197 198 static struct wf_sensor_ops wf_sat_ops = { 199 .get_value = wf_sat_sensor_get, 200 .release = wf_sat_sensor_release, 201 .owner = THIS_MODULE, 202 }; 203 204 static int wf_sat_probe(struct i2c_client *client, 205 const struct i2c_device_id *id) 206 { 207 struct device_node *dev = client->dev.of_node; 208 struct wf_sat *sat; 209 struct wf_sat_sensor *sens; 210 const u32 *reg; 211 const char *loc, *type; 212 u8 chip, core; 213 struct device_node *child; 214 int shift, cpu, index; 215 char *name; 216 int vsens[2], isens[2]; 217 218 sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL); 219 if (sat == NULL) 220 return -ENOMEM; 221 sat->nr = -1; 222 sat->node = of_node_get(dev); 223 kref_init(&sat->ref); 224 mutex_init(&sat->mutex); 225 sat->i2c = client; 226 INIT_LIST_HEAD(&sat->sensors); 227 i2c_set_clientdata(client, sat); 228 229 vsens[0] = vsens[1] = -1; 230 isens[0] = isens[1] = -1; 231 child = NULL; 232 while ((child = of_get_next_child(dev, child)) != NULL) { 233 reg = of_get_property(child, "reg", NULL); 234 type = of_get_property(child, "device_type", NULL); 235 loc = of_get_property(child, "location", NULL); 236 if (reg == NULL || loc == NULL) 237 continue; 238 239 /* the cooked sensors are between 0x30 and 0x37 */ 240 if (*reg < 0x30 || *reg > 0x37) 241 continue; 242 index = *reg - 0x30; 243 244 /* expect location to be CPU [AB][01] ... */ 245 if (strncmp(loc, "CPU ", 4) != 0) 246 continue; 247 chip = loc[4] - 'A'; 248 core = loc[5] - '0'; 249 if (chip > 1 || core > 1) { 250 printk(KERN_ERR "wf_sat_create: don't understand " 251 "location %s for %s\n", loc, child->full_name); 252 continue; 253 } 254 cpu = 2 * chip + core; 255 if (sat->nr < 0) 256 sat->nr = chip; 257 else if (sat->nr != chip) { 258 printk(KERN_ERR "wf_sat_create: can't cope with " 259 "multiple CPU chips on one SAT (%s)\n", loc); 260 continue; 261 } 262 263 if (strcmp(type, "voltage-sensor") == 0) { 264 name = "cpu-voltage"; 265 shift = 4; 266 vsens[core] = index; 267 } else if (strcmp(type, "current-sensor") == 0) { 268 name = "cpu-current"; 269 shift = 8; 270 isens[core] = index; 271 } else if (strcmp(type, "temp-sensor") == 0) { 272 name = "cpu-temp"; 273 shift = 10; 274 } else 275 continue; /* hmmm shouldn't happen */ 276 277 /* the +16 is enough for "cpu-voltage-n" */ 278 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 279 if (sens == NULL) { 280 printk(KERN_ERR "wf_sat_create: couldn't create " 281 "%s sensor %d (no memory)\n", name, cpu); 282 continue; 283 } 284 sens->index = index; 285 sens->index2 = -1; 286 sens->shift = shift; 287 sens->sat = sat; 288 sens->sens.ops = &wf_sat_ops; 289 sens->sens.name = (char *) (sens + 1); 290 snprintf((char *)sens->sens.name, 16, "%s-%d", name, cpu); 291 292 if (wf_register_sensor(&sens->sens)) 293 kfree(sens); 294 else { 295 list_add(&sens->link, &sat->sensors); 296 kref_get(&sat->ref); 297 } 298 } 299 300 /* make the power sensors */ 301 for (core = 0; core < 2; ++core) { 302 if (vsens[core] < 0 || isens[core] < 0) 303 continue; 304 cpu = 2 * sat->nr + core; 305 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL); 306 if (sens == NULL) { 307 printk(KERN_ERR "wf_sat_create: couldn't create power " 308 "sensor %d (no memory)\n", cpu); 309 continue; 310 } 311 sens->index = vsens[core]; 312 sens->index2 = isens[core]; 313 sens->shift = 0; 314 sens->sat = sat; 315 sens->sens.ops = &wf_sat_ops; 316 sens->sens.name = (char *) (sens + 1); 317 snprintf((char *)sens->sens.name, 16, "cpu-power-%d", cpu); 318 319 if (wf_register_sensor(&sens->sens)) 320 kfree(sens); 321 else { 322 list_add(&sens->link, &sat->sensors); 323 kref_get(&sat->ref); 324 } 325 } 326 327 if (sat->nr >= 0) 328 sats[sat->nr] = sat; 329 330 return 0; 331 } 332 333 static int wf_sat_remove(struct i2c_client *client) 334 { 335 struct wf_sat *sat = i2c_get_clientdata(client); 336 struct wf_sat_sensor *sens; 337 338 /* release sensors */ 339 while(!list_empty(&sat->sensors)) { 340 sens = list_first_entry(&sat->sensors, 341 struct wf_sat_sensor, link); 342 list_del(&sens->link); 343 wf_unregister_sensor(&sens->sens); 344 } 345 sat->i2c = NULL; 346 kref_put(&sat->ref, wf_sat_release); 347 348 return 0; 349 } 350 351 static const struct i2c_device_id wf_sat_id[] = { 352 { "MAC,smu-sat", 0 }, 353 { } 354 }; 355 MODULE_DEVICE_TABLE(i2c, wf_sat_id); 356 357 static struct i2c_driver wf_sat_driver = { 358 .driver = { 359 .name = "wf_smu_sat", 360 }, 361 .probe = wf_sat_probe, 362 .remove = wf_sat_remove, 363 .id_table = wf_sat_id, 364 }; 365 366 module_i2c_driver(wf_sat_driver); 367 368 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>"); 369 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control"); 370 MODULE_LICENSE("GPL"); 371