drivers/macintosh/windfarm_smu_sat.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Windfarm PowerMac thermal control.  SMU "satellite" controller sensors.
   4  *
   5  * Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
   6  */
   7
   8 #include <linux/types.h>
   9 #include <linux/errno.h>
  10 #include <linux/kernel.h>
  11 #include <linux/slab.h>
  12 #include <linux/init.h>
  13 #include <linux/wait.h>
  14 #include <linux/i2c.h>
  15 #include <linux/mutex.h>
  16
  17 #include <asm/smu.h>
  18 #include <asm/pmac_low_i2c.h>
  19
  20 #include "windfarm.h"
  21
  22 #define VERSION "1.0"
  23
  24 /* If the cache is older than 800ms we'll refetch it */
  25 #define MAX_AGE         msecs_to_jiffies(800)
  26
  27 struct wf_sat {
  28         struct kref             ref;
  29         int                     nr;
  30         struct mutex            mutex;
  31         unsigned long           last_read; /* jiffies when cache last updated */
  32         u8                      cache[16];
  33         struct list_head        sensors;
  34         struct i2c_client       *i2c;
  35         struct device_node      *node;
  36 };
  37
  38 static struct wf_sat *sats[2];
  39
  40 struct wf_sat_sensor {
  41         struct list_head        link;
  42         int                     index;
  43         int                     index2;         /* used for power sensors */
  44         int                     shift;
  45         struct wf_sat           *sat;
  46         struct wf_sensor        sens;
  47 };
  48
  49 #define wf_to_sat(c)    container_of(c, struct wf_sat_sensor, sens)
  50
  51 struct smu_sdbp_header *smu_sat_get_sdb_partition(unsigned int sat_id, int id,
  52                                                   unsigned int *size)
  53 {
  54         struct wf_sat *sat;
  55         int err;
  56         unsigned int i, len;
  57         u8 *buf;
  58         u8 data[4];
  59
  60         /* TODO: Add the resulting partition to the device-tree */
  61
  62         if (sat_id > 1 || (sat = sats[sat_id]) == NULL)
  63                 return NULL;
  64
  65         err = i2c_smbus_write_word_data(sat->i2c, 8, id << 8);
  66         if (err) {
  67                 printk(KERN_ERR "smu_sat_get_sdb_part wr error %d\n", err);
  68                 return NULL;
  69         }
  70
  71         err = i2c_smbus_read_word_data(sat->i2c, 9);
  72         if (err < 0) {
  73                 printk(KERN_ERR "smu_sat_get_sdb_part rd len error\n");
  74                 return NULL;
  75         }
  76         len = err;
  77         if (len == 0) {
  78                 printk(KERN_ERR "smu_sat_get_sdb_part no partition %x\n", id);
  79                 return NULL;
  80         }
  81
  82         len = le16_to_cpu(len);
  83         len = (len + 3) & ~3;
  84         buf = kmalloc(len, GFP_KERNEL);
  85         if (buf == NULL)
  86                 return NULL;
  87
  88         for (i = 0; i < len; i += 4) {
  89                 err = i2c_smbus_read_i2c_block_data(sat->i2c, 0xa, 4, data);
  90                 if (err < 0) {
  91                         printk(KERN_ERR "smu_sat_get_sdb_part rd err %d\n",
  92                                err);
  93                         goto fail;
  94                 }
  95                 buf[i] = data[1];
  96                 buf[i+1] = data[0];
  97                 buf[i+2] = data[3];
  98                 buf[i+3] = data[2];
  99         }
 100
 101         printk(KERN_DEBUG "sat %d partition %x:", sat_id, id);
 102         print_hex_dump(KERN_DEBUG, "  ", DUMP_PREFIX_OFFSET,
 103                        16, 1, buf, len, false);
 104         if (size)
 105                 *size = len;
 106         return (struct smu_sdbp_header *) buf;
 107
 108  fail:
 109         kfree(buf);
 110         return NULL;
 111 }
 112 EXPORT_SYMBOL_GPL(smu_sat_get_sdb_partition);
 113
 114 /* refresh the cache */
 115 static int wf_sat_read_cache(struct wf_sat *sat)
 116 {
 117         int err;
 118
 119         err = i2c_smbus_read_i2c_block_data(sat->i2c, 0x3f, 16, sat->cache);
 120         if (err < 0)
 121                 return err;
 122         sat->last_read = jiffies;
 123
 124 #ifdef LOTSA_DEBUG
 125         {
 126                 int i;
 127                 printk(KERN_DEBUG "wf_sat_get: data is");
 128                 print_hex_dump(KERN_DEBUG, "  ", DUMP_PREFIX_OFFSET,
 129                                16, 1, sat->cache, 16, false);
 130         }
 131 #endif
 132         return 0;
 133 }
 134
 135 static int wf_sat_sensor_get(struct wf_sensor *sr, s32 *value)
 136 {
 137         struct wf_sat_sensor *sens = wf_to_sat(sr);
 138         struct wf_sat *sat = sens->sat;
 139         int i, err;
 140         s32 val;
 141
 142         if (sat->i2c == NULL)
 143                 return -ENODEV;
 144
 145         mutex_lock(&sat->mutex);
 146         if (time_after(jiffies, (sat->last_read + MAX_AGE))) {
 147                 err = wf_sat_read_cache(sat);
 148                 if (err)
 149                         goto fail;
 150         }
 151
 152         i = sens->index * 2;
 153         val = ((sat->cache[i] << 8) + sat->cache[i+1]) << sens->shift;
 154         if (sens->index2 >= 0) {
 155                 i = sens->index2 * 2;
 156                 /* 4.12 * 8.8 -> 12.20; shift right 4 to get 16.16 */
 157                 val = (val * ((sat->cache[i] << 8) + sat->cache[i+1])) >> 4;
 158         }
 159
 160         *value = val;
 161         err = 0;
 162
 163  fail:
 164         mutex_unlock(&sat->mutex);
 165         return err;
 166 }
 167
 168 static void wf_sat_release(struct kref *ref)
 169 {
 170         struct wf_sat *sat = container_of(ref, struct wf_sat, ref);
 171
 172         if (sat->nr >= 0)
 173                 sats[sat->nr] = NULL;
 174         of_node_put(sat->node);
 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 {
 195         struct device_node *dev = client->dev.of_node;
 196         struct wf_sat *sat;
 197         struct wf_sat_sensor *sens;
 198         const u32 *reg;
 199         const char *loc;
 200         u8 chip, core;
 201         struct device_node *child;
 202         int shift, cpu, index;
 203         char *name;
 204         int vsens[2], isens[2];
 205
 206         sat = kzalloc(sizeof(struct wf_sat), GFP_KERNEL);
 207         if (sat == NULL)
 208                 return -ENOMEM;
 209         sat->nr = -1;
 210         sat->node = of_node_get(dev);
 211         kref_init(&sat->ref);
 212         mutex_init(&sat->mutex);
 213         sat->i2c = client;
 214         INIT_LIST_HEAD(&sat->sensors);
 215         i2c_set_clientdata(client, sat);
 216
 217         vsens[0] = vsens[1] = -1;
 218         isens[0] = isens[1] = -1;
 219         for_each_child_of_node(dev, child) {
 220                 reg = of_get_property(child, "reg", NULL);
 221                 loc = of_get_property(child, "location", NULL);
 222                 if (reg == NULL || loc == NULL)
 223                         continue;
 224
 225                 /* the cooked sensors are between 0x30 and 0x37 */
 226                 if (*reg < 0x30 || *reg > 0x37)
 227                         continue;
 228                 index = *reg - 0x30;
 229
 230                 /* expect location to be CPU [AB][01] ... */
 231                 if (strncmp(loc, "CPU ", 4) != 0)
 232                         continue;
 233                 chip = loc[4] - 'A';
 234                 core = loc[5] - '0';
 235                 if (chip > 1 || core > 1) {
 236                         printk(KERN_ERR "wf_sat_create: don't understand "
 237                                "location %s for %pOF\n", loc, child);
 238                         continue;
 239                 }
 240                 cpu = 2 * chip + core;
 241                 if (sat->nr < 0)
 242                         sat->nr = chip;
 243                 else if (sat->nr != chip) {
 244                         printk(KERN_ERR "wf_sat_create: can't cope with "
 245                                "multiple CPU chips on one SAT (%s)\n", loc);
 246                         continue;
 247                 }
 248
 249                 if (of_node_is_type(child, "voltage-sensor")) {
 250                         name = "cpu-voltage";
 251                         shift = 4;
 252                         vsens[core] = index;
 253                 } else if (of_node_is_type(child, "current-sensor")) {
 254                         name = "cpu-current";
 255                         shift = 8;
 256                         isens[core] = index;
 257                 } else if (of_node_is_type(child, "temp-sensor")) {
 258                         name = "cpu-temp";
 259                         shift = 10;
 260                 } else
 261                         continue;       /* hmmm shouldn't happen */
 262
 263                 /* the +16 is enough for "cpu-voltage-n" */
 264                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
 265                 if (sens == NULL) {
 266                         printk(KERN_ERR "wf_sat_create: couldn't create "
 267                                "%s sensor %d (no memory)\n", name, cpu);
 268                         continue;
 269                 }
 270                 sens->index = index;
 271                 sens->index2 = -1;
 272                 sens->shift = shift;
 273                 sens->sat = sat;
 274                 sens->sens.ops = &wf_sat_ops;
 275                 sens->sens.name = (char *) (sens + 1);
 276                 snprintf((char *)sens->sens.name, 16, "%s-%d", name, cpu);
 277
 278                 if (wf_register_sensor(&sens->sens))
 279                         kfree(sens);
 280                 else {
 281                         list_add(&sens->link, &sat->sensors);
 282                         kref_get(&sat->ref);
 283                 }
 284         }
 285
 286         /* make the power sensors */
 287         for (core = 0; core < 2; ++core) {
 288                 if (vsens[core] < 0 || isens[core] < 0)
 289                         continue;
 290                 cpu = 2 * sat->nr + core;
 291                 sens = kzalloc(sizeof(struct wf_sat_sensor) + 16, GFP_KERNEL);
 292                 if (sens == NULL) {
 293                         printk(KERN_ERR "wf_sat_create: couldn't create power "
 294                                "sensor %d (no memory)\n", cpu);
 295                         continue;
 296                 }
 297                 sens->index = vsens[core];
 298                 sens->index2 = isens[core];
 299                 sens->shift = 0;
 300                 sens->sat = sat;
 301                 sens->sens.ops = &wf_sat_ops;
 302                 sens->sens.name = (char *) (sens + 1);
 303                 snprintf((char *)sens->sens.name, 16, "cpu-power-%d", cpu);
 304
 305                 if (wf_register_sensor(&sens->sens))
 306                         kfree(sens);
 307                 else {
 308                         list_add(&sens->link, &sat->sensors);
 309                         kref_get(&sat->ref);
 310                 }
 311         }
 312
 313         if (sat->nr >= 0)
 314                 sats[sat->nr] = sat;
 315
 316         return 0;
 317 }
 318
 319 static void wf_sat_remove(struct i2c_client *client)
 320 {
 321         struct wf_sat *sat = i2c_get_clientdata(client);
 322         struct wf_sat_sensor *sens;
 323
 324         /* release sensors */
 325         while(!list_empty(&sat->sensors)) {
 326                 sens = list_first_entry(&sat->sensors,
 327                                         struct wf_sat_sensor, link);
 328                 list_del(&sens->link);
 329                 wf_unregister_sensor(&sens->sens);
 330         }
 331         sat->i2c = NULL;
 332         kref_put(&sat->ref, wf_sat_release);
 333 }
 334
 335 static const struct i2c_device_id wf_sat_id[] = {
 336         { "MAC,smu-sat", 0 },
 337         { }
 338 };
 339 MODULE_DEVICE_TABLE(i2c, wf_sat_id);
 340
 341 static const struct of_device_id wf_sat_of_id[] = {
 342         { .compatible = "smu-sat", },
 343         { }
 344 };
 345 MODULE_DEVICE_TABLE(of, wf_sat_of_id);
 346
 347 static struct i2c_driver wf_sat_driver = {
 348         .driver = {
 349                 .name           = "wf_smu_sat",
 350                 .of_match_table = wf_sat_of_id,
 351         },
 352         .probe          = wf_sat_probe,
 353         .remove         = wf_sat_remove,
 354         .id_table       = wf_sat_id,
 355 };
 356
 357 module_i2c_driver(wf_sat_driver);
 358
 359 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
 360 MODULE_DESCRIPTION("SMU satellite sensors for PowerMac thermal control");
 361 MODULE_LICENSE("GPL");