drivers/hwmon/ibmpowernv.c

   1 /*
   2  * IBM PowerNV platform sensors for temperature/fan/voltage/power
   3  * Copyright (C) 2014 IBM
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.
  17  */
  18
  19 #define DRVNAME         "ibmpowernv"
  20 #define pr_fmt(fmt)     DRVNAME ": " fmt
  21
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24 #include <linux/kernel.h>
  25 #include <linux/hwmon.h>
  26 #include <linux/hwmon-sysfs.h>
  27 #include <linux/of.h>
  28 #include <linux/slab.h>
  29
  30 #include <linux/platform_device.h>
  31 #include <asm/opal.h>
  32 #include <linux/err.h>
  33 #include <asm/cputhreads.h>
  34 #include <asm/smp.h>
  35
  36 #define MAX_ATTR_LEN    32
  37 #define MAX_LABEL_LEN   64
  38
  39 /* Sensor suffix name from DT */
  40 #define DT_FAULT_ATTR_SUFFIX            "faulted"
  41 #define DT_DATA_ATTR_SUFFIX             "data"
  42 #define DT_THRESHOLD_ATTR_SUFFIX        "thrs"
  43
  44 /*
  45  * Enumerates all the types of sensors in the POWERNV platform and does index
  46  * into 'struct sensor_group'
  47  */
  48 enum sensors {
  49         FAN,
  50         TEMP,
  51         POWER_SUPPLY,
  52         POWER_INPUT,
  53         MAX_SENSOR_TYPE,
  54 };
  55
  56 #define INVALID_INDEX (-1U)
  57
  58 static struct sensor_group {
  59         const char *name;
  60         const char *compatible;
  61         struct attribute_group group;
  62         u32 attr_count;
  63         u32 hwmon_index;
  64 } sensor_groups[] = {
  65         {"fan", "ibm,opal-sensor-cooling-fan"},
  66         {"temp", "ibm,opal-sensor-amb-temp"},
  67         {"in", "ibm,opal-sensor-power-supply"},
  68         {"power", "ibm,opal-sensor-power"}
  69 };
  70
  71 struct sensor_data {
  72         u32 id; /* An opaque id of the firmware for each sensor */
  73         u32 hwmon_index;
  74         u32 opal_index;
  75         enum sensors type;
  76         char label[MAX_LABEL_LEN];
  77         char name[MAX_ATTR_LEN];
  78         struct device_attribute dev_attr;
  79 };
  80
  81 struct platform_data {
  82         const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
  83         u32 sensors_count; /* Total count of sensors from each group */
  84 };
  85
  86 static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
  87                            char *buf)
  88 {
  89         struct sensor_data *sdata = container_of(devattr, struct sensor_data,
  90                                                  dev_attr);
  91         ssize_t ret;
  92         u32 x;
  93
  94         ret = opal_get_sensor_data(sdata->id, &x);
  95         if (ret)
  96                 return ret;
  97
  98         /* Convert temperature to milli-degrees */
  99         if (sdata->type == TEMP)
 100                 x *= 1000;
 101         /* Convert power to micro-watts */
 102         else if (sdata->type == POWER_INPUT)
 103                 x *= 1000000;
 104
 105         return sprintf(buf, "%u\n", x);
 106 }
 107
 108 static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
 109                           char *buf)
 110 {
 111         struct sensor_data *sdata = container_of(devattr, struct sensor_data,
 112                                                  dev_attr);
 113
 114         return sprintf(buf, "%s\n", sdata->label);
 115 }
 116
 117 static int __init get_logical_cpu(int hwcpu)
 118 {
 119         int cpu;
 120
 121         for_each_possible_cpu(cpu)
 122                 if (get_hard_smp_processor_id(cpu) == hwcpu)
 123                         return cpu;
 124
 125         return -ENOENT;
 126 }
 127
 128 static void __init make_sensor_label(struct device_node *np,
 129                                      struct sensor_data *sdata,
 130                                      const char *label)
 131 {
 132         u32 id;
 133         size_t n;
 134
 135         n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
 136
 137         /*
 138          * Core temp pretty print
 139          */
 140         if (!of_property_read_u32(np, "ibm,pir", &id)) {
 141                 int cpuid = get_logical_cpu(id);
 142
 143                 if (cpuid >= 0)
 144                         /*
 145                          * The digital thermal sensors are associated
 146                          * with a core.
 147                          */
 148                         n += snprintf(sdata->label + n,
 149                                       sizeof(sdata->label) - n, " %d",
 150                                       cpuid);
 151                 else
 152                         n += snprintf(sdata->label + n,
 153                                       sizeof(sdata->label) - n, " phy%d", id);
 154         }
 155
 156         /*
 157          * Membuffer pretty print
 158          */
 159         if (!of_property_read_u32(np, "ibm,chip-id", &id))
 160                 n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
 161                               " %d", id & 0xffff);
 162 }
 163
 164 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
 165 {
 166         char *hash_pos = strchr(name, '#');
 167         char buf[8] = { 0 };
 168         char *dash_pos;
 169         u32 copy_len;
 170         int err;
 171
 172         if (!hash_pos)
 173                 return -EINVAL;
 174
 175         dash_pos = strchr(hash_pos, '-');
 176         if (!dash_pos)
 177                 return -EINVAL;
 178
 179         copy_len = dash_pos - hash_pos - 1;
 180         if (copy_len >= sizeof(buf))
 181                 return -EINVAL;
 182
 183         strncpy(buf, hash_pos + 1, copy_len);
 184
 185         err = kstrtou32(buf, 10, index);
 186         if (err)
 187                 return err;
 188
 189         strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
 190
 191         return 0;
 192 }
 193
 194 static const char *convert_opal_attr_name(enum sensors type,
 195                                           const char *opal_attr)
 196 {
 197         const char *attr_name = NULL;
 198
 199         if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
 200                 attr_name = "fault";
 201         } else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
 202                 attr_name = "input";
 203         } else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
 204                 if (type == TEMP)
 205                         attr_name = "max";
 206                 else if (type == FAN)
 207                         attr_name = "min";
 208         }
 209
 210         return attr_name;
 211 }
 212
 213 /*
 214  * This function translates the DT node name into the 'hwmon' attribute name.
 215  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
 216  * which need to be mapped as fan2_input, temp1_max respectively before
 217  * populating them inside hwmon device class.
 218  */
 219 static const char *parse_opal_node_name(const char *node_name,
 220                                         enum sensors type, u32 *index)
 221 {
 222         char attr_suffix[MAX_ATTR_LEN];
 223         const char *attr_name;
 224         int err;
 225
 226         err = get_sensor_index_attr(node_name, index, attr_suffix);
 227         if (err)
 228                 return ERR_PTR(err);
 229
 230         attr_name = convert_opal_attr_name(type, attr_suffix);
 231         if (!attr_name)
 232                 return ERR_PTR(-ENOENT);
 233
 234         return attr_name;
 235 }
 236
 237 static int get_sensor_type(struct device_node *np)
 238 {
 239         enum sensors type;
 240         const char *str;
 241
 242         for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 243                 if (of_device_is_compatible(np, sensor_groups[type].compatible))
 244                         return type;
 245         }
 246
 247         /*
 248          * Let's check if we have a newer device tree
 249          */
 250         if (!of_device_is_compatible(np, "ibm,opal-sensor"))
 251                 return MAX_SENSOR_TYPE;
 252
 253         if (of_property_read_string(np, "sensor-type", &str))
 254                 return MAX_SENSOR_TYPE;
 255
 256         for (type = 0; type < MAX_SENSOR_TYPE; type++)
 257                 if (!strcmp(str, sensor_groups[type].name))
 258                         return type;
 259
 260         return MAX_SENSOR_TYPE;
 261 }
 262
 263 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
 264                                   struct sensor_data *sdata_table, int count)
 265 {
 266         int i;
 267
 268         /*
 269          * We don't use the OPAL index on newer device trees
 270          */
 271         if (sdata->opal_index != INVALID_INDEX) {
 272                 for (i = 0; i < count; i++)
 273                         if (sdata_table[i].opal_index == sdata->opal_index &&
 274                             sdata_table[i].type == sdata->type)
 275                                 return sdata_table[i].hwmon_index;
 276         }
 277         return ++sensor_groups[sdata->type].hwmon_index;
 278 }
 279
 280 static int populate_attr_groups(struct platform_device *pdev)
 281 {
 282         struct platform_data *pdata = platform_get_drvdata(pdev);
 283         const struct attribute_group **pgroups = pdata->attr_groups;
 284         struct device_node *opal, *np;
 285         enum sensors type;
 286
 287         opal = of_find_node_by_path("/ibm,opal/sensors");
 288         for_each_child_of_node(opal, np) {
 289                 const char *label;
 290
 291                 if (np->name == NULL)
 292                         continue;
 293
 294                 type = get_sensor_type(np);
 295                 if (type == MAX_SENSOR_TYPE)
 296                         continue;
 297
 298                 sensor_groups[type].attr_count++;
 299
 300                 /*
 301                  * add a new attribute for labels
 302                  */
 303                 if (!of_property_read_string(np, "label", &label))
 304                         sensor_groups[type].attr_count++;
 305         }
 306
 307         of_node_put(opal);
 308
 309         for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 310                 sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
 311                                         sizeof(struct attribute *) *
 312                                         (sensor_groups[type].attr_count + 1),
 313                                         GFP_KERNEL);
 314                 if (!sensor_groups[type].group.attrs)
 315                         return -ENOMEM;
 316
 317                 pgroups[type] = &sensor_groups[type].group;
 318                 pdata->sensors_count += sensor_groups[type].attr_count;
 319                 sensor_groups[type].attr_count = 0;
 320         }
 321
 322         return 0;
 323 }
 324
 325 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
 326                               ssize_t (*show)(struct device *dev,
 327                                               struct device_attribute *attr,
 328                                               char *buf))
 329 {
 330         snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
 331                  sensor_groups[sdata->type].name, sdata->hwmon_index,
 332                  attr_name);
 333
 334         sysfs_attr_init(&sdata->dev_attr.attr);
 335         sdata->dev_attr.attr.name = sdata->name;
 336         sdata->dev_attr.attr.mode = S_IRUGO;
 337         sdata->dev_attr.show = show;
 338 }
 339
 340 /*
 341  * Iterate through the device tree for each child of 'sensors' node, create
 342  * a sysfs attribute file, the file is named by translating the DT node name
 343  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
 344  * etc..
 345  */
 346 static int create_device_attrs(struct platform_device *pdev)
 347 {
 348         struct platform_data *pdata = platform_get_drvdata(pdev);
 349         const struct attribute_group **pgroups = pdata->attr_groups;
 350         struct device_node *opal, *np;
 351         struct sensor_data *sdata;
 352         u32 sensor_id;
 353         enum sensors type;
 354         u32 count = 0;
 355         int err = 0;
 356
 357         opal = of_find_node_by_path("/ibm,opal/sensors");
 358         sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
 359                              GFP_KERNEL);
 360         if (!sdata) {
 361                 err = -ENOMEM;
 362                 goto exit_put_node;
 363         }
 364
 365         for_each_child_of_node(opal, np) {
 366                 const char *attr_name;
 367                 u32 opal_index;
 368                 const char *label;
 369
 370                 if (np->name == NULL)
 371                         continue;
 372
 373                 type = get_sensor_type(np);
 374                 if (type == MAX_SENSOR_TYPE)
 375                         continue;
 376
 377                 /*
 378                  * Newer device trees use a "sensor-data" property
 379                  * name for input.
 380                  */
 381                 if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
 382                     of_property_read_u32(np, "sensor-data", &sensor_id)) {
 383                         dev_info(&pdev->dev,
 384                                  "'sensor-id' missing in the node '%s'\n",
 385                                  np->name);
 386                         continue;
 387                 }
 388
 389                 sdata[count].id = sensor_id;
 390                 sdata[count].type = type;
 391
 392                 /*
 393                  * If we can not parse the node name, it means we are
 394                  * running on a newer device tree. We can just forget
 395                  * about the OPAL index and use a defaut value for the
 396                  * hwmon attribute name
 397                  */
 398                 attr_name = parse_opal_node_name(np->name, type, &opal_index);
 399                 if (IS_ERR(attr_name)) {
 400                         attr_name = "input";
 401                         opal_index = INVALID_INDEX;
 402                 }
 403
 404                 sdata[count].opal_index = opal_index;
 405                 sdata[count].hwmon_index =
 406                         get_sensor_hwmon_index(&sdata[count], sdata, count);
 407
 408                 create_hwmon_attr(&sdata[count], attr_name, show_sensor);
 409
 410                 pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 411                                 &sdata[count++].dev_attr.attr;
 412
 413                 if (!of_property_read_string(np, "label", &label)) {
 414                         /*
 415                          * For the label attribute, we can reuse the
 416                          * "properties" of the previous "input"
 417                          * attribute. They are related to the same
 418                          * sensor.
 419                          */
 420                         sdata[count].type = type;
 421                         sdata[count].opal_index = sdata[count - 1].opal_index;
 422                         sdata[count].hwmon_index = sdata[count - 1].hwmon_index;
 423
 424                         make_sensor_label(np, &sdata[count], label);
 425
 426                         create_hwmon_attr(&sdata[count], "label", show_label);
 427
 428                         pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 429                                 &sdata[count++].dev_attr.attr;
 430                 }
 431         }
 432
 433 exit_put_node:
 434         of_node_put(opal);
 435         return err;
 436 }
 437
 438 static int ibmpowernv_probe(struct platform_device *pdev)
 439 {
 440         struct platform_data *pdata;
 441         struct device *hwmon_dev;
 442         int err;
 443
 444         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 445         if (!pdata)
 446                 return -ENOMEM;
 447
 448         platform_set_drvdata(pdev, pdata);
 449         pdata->sensors_count = 0;
 450         err = populate_attr_groups(pdev);
 451         if (err)
 452                 return err;
 453
 454         /* Create sysfs attribute data for each sensor found in the DT */
 455         err = create_device_attrs(pdev);
 456         if (err)
 457                 return err;
 458
 459         /* Finally, register with hwmon */
 460         hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
 461                                                            pdata,
 462                                                            pdata->attr_groups);
 463
 464         return PTR_ERR_OR_ZERO(hwmon_dev);
 465 }
 466
 467 static const struct platform_device_id opal_sensor_driver_ids[] = {
 468         {
 469                 .name = "opal-sensor",
 470         },
 471         { }
 472 };
 473 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
 474
 475 static const struct of_device_id opal_sensor_match[] = {
 476         { .compatible   = "ibm,opal-sensor" },
 477         { },
 478 };
 479 MODULE_DEVICE_TABLE(of, opal_sensor_match);
 480
 481 static struct platform_driver ibmpowernv_driver = {
 482         .probe          = ibmpowernv_probe,
 483         .id_table       = opal_sensor_driver_ids,
 484         .driver         = {
 485                 .name   = DRVNAME,
 486                 .of_match_table = opal_sensor_match,
 487         },
 488 };
 489
 490 module_platform_driver(ibmpowernv_driver);
 491
 492 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
 493 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
 494 MODULE_LICENSE("GPL");