drivers/macintosh/windfarm_smu_sat.c

   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 /* If the cache is older than 800ms we'll refetch it */
  26 #define MAX_AGE         msecs_to_jiffies(800)
  27
  28 struct wf_sat {
  29         struct kref             ref;
  30         int                     nr;
  31         struct mutex            mutex;
  32         unsigned long           last_read; /* jiffies when cache last updated */
  33         u8                      cache[16];
  34         struct list_head        sensors;
  35         struct i2c_client       *i2c;
  36         struct device_node      *node;
  37 };
  38
  39 static struct wf_sat *sats[2];
  40
  41 struct wf_sat_sensor {
  42         struct list_head        link;
  43         int                     index;
  44         int                     index2;         /* used for power sensors */
  45         int                     shift;
  46         struct wf_sat           *sat;
  47         struct wf_sensor        sens;
  48 };
  49
  50 #define wf_to_sat(c)    container_of(c, struct wf_sat_sensor, sens)
  51
  52 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
  53                                                   unsigned int *size)
  54 {
  55         struct wf_sat *sat;
  56         int err;
  57         unsigned int i, len;
  58         u8 *buf;
  59         u8 data[4];
  60
  61         /* TODO: Add the resulting partition to the device-tree */
  62
  63         if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
  64                 return NULL;
  65
  66         err = i2c_smbus_write_word_data(sat->i2c, 8, id << 8);
  67         if (err) {
  68                 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
  69                 return NULL;
  70         }
  71
  72         err = i2c_smbus_read_word_data(sat->i2c, 9);
  73         if (err < 0) {
  74                 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
  75                 return NULL;
  76         }
  77         len = err;
  78         if (len == 0) {
  79                 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
  80                 return NULL;
  81         }
  82
  83         len = le16_to_cpu(len);
  84         len = (len + 3) & ~3;
  85         buf = kmalloc(len, GFP_KERNEL);
  86         if (buf == NULL)
  87                 return NULL;
  88
  89         for (i = 0; i < len; i += 4) {
  90                 err = i2c_smbus_read_i2c_block_data(sat->i2c, 0xa, 4, data);
  91                 if (err < 0) {
  92                         printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
  93                                err);
  94                         goto fail;
  95                 }
  96                 buf[i] = data[1];
  97                 buf[i+1] = data[0];
  98                 buf[i+2] = data[3];
  99                 buf[i+3] = data[2];
 100         }
 101
 102         printk(KERN_DEBUG "sat %d partition %x:", sat_id, id);
 103         print_hex_dump(KERN_DEBUG, "  ", DUMP_PREFIX_OFFSET,
 104                        16, 1, buf, len, false);
 105         if (size)
 106                 *size = len;
 107         return (struct smu_sdbp_header *) buf;
 108
 109  fail:
 110         kfree(buf);
 111         return NULL;
 112 }
 113 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);
 114
 115 /* refresh the cache */
 116 static int wf_sat_read_cache(struct wf_sat *sat)
 117 {
 118         int err;
 119
 120         err = i2c_smbus_read_i2c_block_data(sat->i2c, 0x3f, 16, sat->cache);
 121         if (err < 0)
 122                 return err;
 123         sat->last_read = jiffies;
 124
 125 #ifdef LOTSA_DEBUG
 126         {
 127                 int i;
 128                 printk(KERN_DEBUG "wf_sat_get: data is");
 129                 print_hex_dump(KERN_DEBUG, "  ", DUMP_PREFIX_OFFSET,
 130                                16, 1, sat->cache, 16, false);
 131         }
 132 #endif
 133         return 0;
 134 }
 135
 136 static int wf_sat_sensor_get(struct wf_sensor *sr, s32 *value)
 137 {
 138         struct wf_sat_sensor *sens = wf_to_sat(sr);
 139         struct wf_sat *sat = sens->sat;
 140         int i, err;
 141         s32 val;
 142
 143         if (sat->i2c == NULL)
 144                 return -ENODEV;
 145
 146         mutex_lock(&sat->mutex);
 147         if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
 148                 err = wf_sat_read_cache(sat);
 149                 if (err)
 150                         goto fail;
 151         }
 152
 153         i = sens->index * 2;
 154         val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
 155         if (sens->index2 >= 0) {
 156                 i = sens->index2 * 2;
 157                 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
 158                 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
 159         }
 160
 161         *value = val;
 162         err = 0;
 163
 164  fail:
 165         mutex_unlock(&sat->mutex);
 166         return err;
 167 }
 168
 169 static void wf_sat_release(struct kref *ref)
 170 {
 171         struct wf_sat *sat = container_of(ref, struct wf_sat, ref);
 172
 173         if (sat->nr >= 0)
 174                 sats[sat->nr] = NULL;
 175         kfree(sat);
 176 }
 177
 178 static void wf_sat_sensor_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         kfree(sens);
 184         kref_put(&sat->ref, wf_sat_release);
 185 }
 186
 187 static const struct wf_sensor_ops wf_sat_ops = {
 188         .get_value      = wf_sat_sensor_get,
 189         .release        = wf_sat_sensor_release,
 190         .owner          = THIS_MODULE,
 191 };
 192
 193 static int wf_sat_probe(struct i2c_client *client,
 194                         const struct i2c_device_id *id)
 195 {
 196         struct device_node *dev = client->dev.of_node;
 197         struct wf_sat *sat;
 198         struct wf_sat_sensor *sens;
 199         const u32 *reg;
 200         const char *loc, *type;
 201         u8 chip, core;
 202         struct device_node *child;
 203         int shift, cpu, index;
 204         char *name;
 205         int vsens[2], isens[2];
 206
 207         sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
 208         if (sat == NULL)
 209                 return -ENOMEM;
 210         sat->nr = -1;
 211         sat->node = of_node_get(dev);
 212         kref_init(&sat->ref);
 213         mutex_init(&sat->mutex);
 214         sat->i2c = client;
 215         INIT_LIST_HEAD(&sat->sensors);
 216         i2c_set_clientdata(client, sat);
 217
 218         vsens[0] = vsens[1] = -1;
 219         isens[0] = isens[1] = -1;
 220         child = NULL;
 221         while ((child = of_get_next_child(dev, child)) != NULL) {
 222                 reg = of_get_property(child, "reg", NULL);
 223                 type = of_get_property(child, "device_type", NULL);
 224                 loc = of_get_property(child, "location", NULL);
 225                 if (reg == NULL || loc == NULL)
 226                         continue;
 227
 228                 /* the cooked sensors are between 0x30 and 0x37 */
 229                 if (*reg < 0x30 || *reg > 0x37)
 230                         continue;
 231                 index = *reg - 0x30;
 232
 233                 /* expect location to be CPU [AB][01] ... */
 234                 if (strncmp(loc, "CPU ", 4) != 0)
 235                         continue;
 236                 chip = loc[4] - 'A';
 237                 core = loc[5] - '0';
 238                 if (chip > 1 || core > 1) {
 239                         printk(KERN_ERR "wf_sat_create: don't understand "
 240                                "location %s for %pOF\n", loc, child);
 241                         continue;
 242                 }
 243                 cpu = 2 * chip + core;
 244                 if (sat->nr < 0)
 245                         sat->nr = chip;
 246                 else if (sat->nr != chip) {
 247                         printk(KERN_ERR "wf_sat_create: can't cope with "
 248                                "multiple CPU chips on one SAT (%s)\n", loc);
 249                         continue;
 250                 }
 251
 252                 if (strcmp(type, "voltage-sensor") == 0) {
 253                         name = "cpu-voltage";
 254                         shift = 4;
 255                         vsens[core] = index;
 256                 } else if (strcmp(type, "current-sensor") == 0) {
 257                         name = "cpu-current";
 258                         shift = 8;
 259                         isens[core] = index;
 260                 } else if (strcmp(type, "temp-sensor") == 0) {
 261                         name = "cpu-temp";
 262                         shift = 10;
 263                 } else
 264                         continue;       /* hmmm shouldn't happen */
 265
 266                 /* the +16 is enough for "cpu-voltage-n" */
 267                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
 268                 if (sens == NULL) {
 269                         printk(KERN_ERR "wf_sat_create: couldn't create "
 270                                "%s sensor %d (no memory)\n", name, cpu);
 271                         continue;
 272                 }
 273                 sens->index = index;
 274                 sens->index2 = -1;
 275                 sens->shift = shift;
 276                 sens->sat = sat;
 277                 sens->sens.ops = &wf_sat_ops;
 278                 sens->sens.name = (char *) (sens + 1);
 279                 snprintf((char *)sens->sens.name, 16, "%s-%d", name, cpu);
 280
 281                 if (wf_register_sensor(&sens->sens))
 282                         kfree(sens);
 283                 else {
 284                         list_add(&sens->link, &sat->sensors);
 285                         kref_get(&sat->ref);
 286                 }
 287         }
 288
 289         /* make the power sensors */
 290         for (core = 0; core < 2; ++core) {
 291                 if (vsens[core] < 0 || isens[core] < 0)
 292                         continue;
 293                 cpu = 2 * sat->nr + core;
 294                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
 295                 if (sens == NULL) {
 296                         printk(KERN_ERR "wf_sat_create: couldn't create power "
 297                                "sensor %d (no memory)\n", cpu);
 298                         continue;
 299                 }
 300                 sens->index = vsens[core];
 301                 sens->index2 = isens[core];
 302                 sens->shift = 0;
 303                 sens->sat = sat;
 304                 sens->sens.ops = &wf_sat_ops;
 305                 sens->sens.name = (char *) (sens + 1);
 306                 snprintf((char *)sens->sens.name, 16, "cpu-power-%d", cpu);
 307
 308                 if (wf_register_sensor(&sens->sens))
 309                         kfree(sens);
 310                 else {
 311                         list_add(&sens->link, &sat->sensors);
 312                         kref_get(&sat->ref);
 313                 }
 314         }
 315
 316         if (sat->nr >= 0)
 317                 sats[sat->nr] = sat;
 318
 319         return 0;
 320 }
 321
 322 static int wf_sat_remove(struct i2c_client *client)
 323 {
 324         struct wf_sat *sat = i2c_get_clientdata(client);
 325         struct wf_sat_sensor *sens;
 326
 327         /* release sensors */
 328         while(!list_empty(&sat->sensors)) {
 329                 sens = list_first_entry(&sat->sensors,
 330                                         struct wf_sat_sensor, link);
 331                 list_del(&sens->link);
 332                 wf_unregister_sensor(&sens->sens);
 333         }
 334         sat->i2c = NULL;
 335         kref_put(&sat->ref, wf_sat_release);
 336
 337         return 0;
 338 }
 339
 340 static const struct i2c_device_id wf_sat_id[] = {
 341         { "MAC,smu-sat", 0 },
 342         { }
 343 };
 344 MODULE_DEVICE_TABLE(i2c, wf_sat_id);
 345
 346 static struct i2c_driver wf_sat_driver = {
 347         .driver = {
 348                 .name           = "wf_smu_sat",
 349         },
 350         .probe          = wf_sat_probe,
 351         .remove         = wf_sat_remove,
 352         .id_table       = wf_sat_id,
 353 };
 354
 355 module_i2c_driver(wf_sat_driver);
 356
 357 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
 358 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
 359 MODULE_LICENSE("GPL");