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         CURRENT,
  54         MAX_SENSOR_TYPE,
  55 };
  56
  57 #define INVALID_INDEX (-1U)
  58
  59 /*
  60  * 'compatible' string properties for sensor types as defined in old
  61  * PowerNV firmware (skiboot). These are ordered as 'enum sensors'.
  62  */
  63 static const char * const legacy_compatibles[] = {
  64         "ibm,opal-sensor-cooling-fan",
  65         "ibm,opal-sensor-amb-temp",
  66         "ibm,opal-sensor-power-supply",
  67         "ibm,opal-sensor-power"
  68 };
  69
  70 static struct sensor_group {
  71         const char *name; /* matches property 'sensor-type' */
  72         struct attribute_group group;
  73         u32 attr_count;
  74         u32 hwmon_index;
  75 } sensor_groups[] = {
  76         { "fan"   },
  77         { "temp"  },
  78         { "in"    },
  79         { "power" },
  80         { "curr"  },
  81 };
  82
  83 struct sensor_data {
  84         u32 id; /* An opaque id of the firmware for each sensor */
  85         u32 hwmon_index;
  86         u32 opal_index;
  87         enum sensors type;
  88         char label[MAX_LABEL_LEN];
  89         char name[MAX_ATTR_LEN];
  90         struct device_attribute dev_attr;
  91 };
  92
  93 struct platform_data {
  94         const struct attribute_group *attr_groups[MAX_SENSOR_TYPE + 1];
  95         u32 sensors_count; /* Total count of sensors from each group */
  96 };
  97
  98 static ssize_t show_sensor(struct device *dev, struct device_attribute *devattr,
  99                            char *buf)
 100 {
 101         struct sensor_data *sdata = container_of(devattr, struct sensor_data,
 102                                                  dev_attr);
 103         ssize_t ret;
 104         u32 x;
 105
 106         ret = opal_get_sensor_data(sdata->id, &x);
 107         if (ret)
 108                 return ret;
 109
 110         /* Convert temperature to milli-degrees */
 111         if (sdata->type == TEMP)
 112                 x *= 1000;
 113         /* Convert power to micro-watts */
 114         else if (sdata->type == POWER_INPUT)
 115                 x *= 1000000;
 116
 117         return sprintf(buf, "%u\n", x);
 118 }
 119
 120 static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
 121                           char *buf)
 122 {
 123         struct sensor_data *sdata = container_of(devattr, struct sensor_data,
 124                                                  dev_attr);
 125
 126         return sprintf(buf, "%s\n", sdata->label);
 127 }
 128
 129 static int __init get_logical_cpu(int hwcpu)
 130 {
 131         int cpu;
 132
 133         for_each_possible_cpu(cpu)
 134                 if (get_hard_smp_processor_id(cpu) == hwcpu)
 135                         return cpu;
 136
 137         return -ENOENT;
 138 }
 139
 140 static void __init make_sensor_label(struct device_node *np,
 141                                      struct sensor_data *sdata,
 142                                      const char *label)
 143 {
 144         u32 id;
 145         size_t n;
 146
 147         n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
 148
 149         /*
 150          * Core temp pretty print
 151          */
 152         if (!of_property_read_u32(np, "ibm,pir", &id)) {
 153                 int cpuid = get_logical_cpu(id);
 154
 155                 if (cpuid >= 0)
 156                         /*
 157                          * The digital thermal sensors are associated
 158                          * with a core.
 159                          */
 160                         n += snprintf(sdata->label + n,
 161                                       sizeof(sdata->label) - n, " %d",
 162                                       cpuid);
 163                 else
 164                         n += snprintf(sdata->label + n,
 165                                       sizeof(sdata->label) - n, " phy%d", id);
 166         }
 167
 168         /*
 169          * Membuffer pretty print
 170          */
 171         if (!of_property_read_u32(np, "ibm,chip-id", &id))
 172                 n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
 173                               " %d", id & 0xffff);
 174 }
 175
 176 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
 177 {
 178         char *hash_pos = strchr(name, '#');
 179         char buf[8] = { 0 };
 180         char *dash_pos;
 181         u32 copy_len;
 182         int err;
 183
 184         if (!hash_pos)
 185                 return -EINVAL;
 186
 187         dash_pos = strchr(hash_pos, '-');
 188         if (!dash_pos)
 189                 return -EINVAL;
 190
 191         copy_len = dash_pos - hash_pos - 1;
 192         if (copy_len >= sizeof(buf))
 193                 return -EINVAL;
 194
 195         strncpy(buf, hash_pos + 1, copy_len);
 196
 197         err = kstrtou32(buf, 10, index);
 198         if (err)
 199                 return err;
 200
 201         strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
 202
 203         return 0;
 204 }
 205
 206 static const char *convert_opal_attr_name(enum sensors type,
 207                                           const char *opal_attr)
 208 {
 209         const char *attr_name = NULL;
 210
 211         if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
 212                 attr_name = "fault";
 213         } else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
 214                 attr_name = "input";
 215         } else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
 216                 if (type == TEMP)
 217                         attr_name = "max";
 218                 else if (type == FAN)
 219                         attr_name = "min";
 220         }
 221
 222         return attr_name;
 223 }
 224
 225 /*
 226  * This function translates the DT node name into the 'hwmon' attribute name.
 227  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
 228  * which need to be mapped as fan2_input, temp1_max respectively before
 229  * populating them inside hwmon device class.
 230  */
 231 static const char *parse_opal_node_name(const char *node_name,
 232                                         enum sensors type, u32 *index)
 233 {
 234         char attr_suffix[MAX_ATTR_LEN];
 235         const char *attr_name;
 236         int err;
 237
 238         err = get_sensor_index_attr(node_name, index, attr_suffix);
 239         if (err)
 240                 return ERR_PTR(err);
 241
 242         attr_name = convert_opal_attr_name(type, attr_suffix);
 243         if (!attr_name)
 244                 return ERR_PTR(-ENOENT);
 245
 246         return attr_name;
 247 }
 248
 249 static int get_sensor_type(struct device_node *np)
 250 {
 251         enum sensors type;
 252         const char *str;
 253
 254         for (type = 0; type < ARRAY_SIZE(legacy_compatibles); type++) {
 255                 if (of_device_is_compatible(np, legacy_compatibles[type]))
 256                         return type;
 257         }
 258
 259         /*
 260          * Let's check if we have a newer device tree
 261          */
 262         if (!of_device_is_compatible(np, "ibm,opal-sensor"))
 263                 return MAX_SENSOR_TYPE;
 264
 265         if (of_property_read_string(np, "sensor-type", &str))
 266                 return MAX_SENSOR_TYPE;
 267
 268         for (type = 0; type < MAX_SENSOR_TYPE; type++)
 269                 if (!strcmp(str, sensor_groups[type].name))
 270                         return type;
 271
 272         return MAX_SENSOR_TYPE;
 273 }
 274
 275 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
 276                                   struct sensor_data *sdata_table, int count)
 277 {
 278         int i;
 279
 280         /*
 281          * We don't use the OPAL index on newer device trees
 282          */
 283         if (sdata->opal_index != INVALID_INDEX) {
 284                 for (i = 0; i < count; i++)
 285                         if (sdata_table[i].opal_index == sdata->opal_index &&
 286                             sdata_table[i].type == sdata->type)
 287                                 return sdata_table[i].hwmon_index;
 288         }
 289         return ++sensor_groups[sdata->type].hwmon_index;
 290 }
 291
 292 static int populate_attr_groups(struct platform_device *pdev)
 293 {
 294         struct platform_data *pdata = platform_get_drvdata(pdev);
 295         const struct attribute_group **pgroups = pdata->attr_groups;
 296         struct device_node *opal, *np;
 297         enum sensors type;
 298
 299         opal = of_find_node_by_path("/ibm,opal/sensors");
 300         for_each_child_of_node(opal, np) {
 301                 const char *label;
 302
 303                 if (np->name == NULL)
 304                         continue;
 305
 306                 type = get_sensor_type(np);
 307                 if (type == MAX_SENSOR_TYPE)
 308                         continue;
 309
 310                 sensor_groups[type].attr_count++;
 311
 312                 /*
 313                  * add attributes for labels, min and max
 314                  */
 315                 if (!of_property_read_string(np, "label", &label))
 316                         sensor_groups[type].attr_count++;
 317                 if (of_find_property(np, "sensor-data-min", NULL))
 318                         sensor_groups[type].attr_count++;
 319                 if (of_find_property(np, "sensor-data-max", NULL))
 320                         sensor_groups[type].attr_count++;
 321         }
 322
 323         of_node_put(opal);
 324
 325         for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 326                 sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
 327                                         sizeof(struct attribute *) *
 328                                         (sensor_groups[type].attr_count + 1),
 329                                         GFP_KERNEL);
 330                 if (!sensor_groups[type].group.attrs)
 331                         return -ENOMEM;
 332
 333                 pgroups[type] = &sensor_groups[type].group;
 334                 pdata->sensors_count += sensor_groups[type].attr_count;
 335                 sensor_groups[type].attr_count = 0;
 336         }
 337
 338         return 0;
 339 }
 340
 341 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
 342                               ssize_t (*show)(struct device *dev,
 343                                               struct device_attribute *attr,
 344                                               char *buf))
 345 {
 346         snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
 347                  sensor_groups[sdata->type].name, sdata->hwmon_index,
 348                  attr_name);
 349
 350         sysfs_attr_init(&sdata->dev_attr.attr);
 351         sdata->dev_attr.attr.name = sdata->name;
 352         sdata->dev_attr.attr.mode = S_IRUGO;
 353         sdata->dev_attr.show = show;
 354 }
 355
 356 static void populate_sensor(struct sensor_data *sdata, int od, int hd, int sid,
 357                             const char *attr_name, enum sensors type,
 358                             const struct attribute_group *pgroup,
 359                             ssize_t (*show)(struct device *dev,
 360                                             struct device_attribute *attr,
 361                                             char *buf))
 362 {
 363         sdata->id = sid;
 364         sdata->type = type;
 365         sdata->opal_index = od;
 366         sdata->hwmon_index = hd;
 367         create_hwmon_attr(sdata, attr_name, show);
 368         pgroup->attrs[sensor_groups[type].attr_count++] = &sdata->dev_attr.attr;
 369 }
 370
 371 static char *get_max_attr(enum sensors type)
 372 {
 373         switch (type) {
 374         case POWER_INPUT:
 375                 return "input_highest";
 376         default:
 377                 return "highest";
 378         }
 379 }
 380
 381 static char *get_min_attr(enum sensors type)
 382 {
 383         switch (type) {
 384         case POWER_INPUT:
 385                 return "input_lowest";
 386         default:
 387                 return "lowest";
 388         }
 389 }
 390
 391 /*
 392  * Iterate through the device tree for each child of 'sensors' node, create
 393  * a sysfs attribute file, the file is named by translating the DT node name
 394  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
 395  * etc..
 396  */
 397 static int create_device_attrs(struct platform_device *pdev)
 398 {
 399         struct platform_data *pdata = platform_get_drvdata(pdev);
 400         const struct attribute_group **pgroups = pdata->attr_groups;
 401         struct device_node *opal, *np;
 402         struct sensor_data *sdata;
 403         u32 sensor_id;
 404         enum sensors type;
 405         u32 count = 0;
 406         int err = 0;
 407
 408         opal = of_find_node_by_path("/ibm,opal/sensors");
 409         sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
 410                              GFP_KERNEL);
 411         if (!sdata) {
 412                 err = -ENOMEM;
 413                 goto exit_put_node;
 414         }
 415
 416         for_each_child_of_node(opal, np) {
 417                 const char *attr_name;
 418                 u32 opal_index;
 419                 const char *label;
 420
 421                 if (np->name == NULL)
 422                         continue;
 423
 424                 type = get_sensor_type(np);
 425                 if (type == MAX_SENSOR_TYPE)
 426                         continue;
 427
 428                 /*
 429                  * Newer device trees use a "sensor-data" property
 430                  * name for input.
 431                  */
 432                 if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
 433                     of_property_read_u32(np, "sensor-data", &sensor_id)) {
 434                         dev_info(&pdev->dev,
 435                                  "'sensor-id' missing in the node '%s'\n",
 436                                  np->name);
 437                         continue;
 438                 }
 439
 440                 sdata[count].id = sensor_id;
 441                 sdata[count].type = type;
 442
 443                 /*
 444                  * If we can not parse the node name, it means we are
 445                  * running on a newer device tree. We can just forget
 446                  * about the OPAL index and use a defaut value for the
 447                  * hwmon attribute name
 448                  */
 449                 attr_name = parse_opal_node_name(np->name, type, &opal_index);
 450                 if (IS_ERR(attr_name)) {
 451                         attr_name = "input";
 452                         opal_index = INVALID_INDEX;
 453                 }
 454
 455                 sdata[count].opal_index = opal_index;
 456                 sdata[count].hwmon_index =
 457                         get_sensor_hwmon_index(&sdata[count], sdata, count);
 458
 459                 create_hwmon_attr(&sdata[count], attr_name, show_sensor);
 460
 461                 pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 462                                 &sdata[count++].dev_attr.attr;
 463
 464                 if (!of_property_read_string(np, "label", &label)) {
 465                         /*
 466                          * For the label attribute, we can reuse the
 467                          * "properties" of the previous "input"
 468                          * attribute. They are related to the same
 469                          * sensor.
 470                          */
 471
 472                         make_sensor_label(np, &sdata[count], label);
 473                         populate_sensor(&sdata[count], opal_index,
 474                                         sdata[count - 1].hwmon_index,
 475                                         sensor_id, "label", type, pgroups[type],
 476                                         show_label);
 477                         count++;
 478                 }
 479
 480                 if (!of_property_read_u32(np, "sensor-data-max", &sensor_id)) {
 481                         attr_name = get_max_attr(type);
 482                         populate_sensor(&sdata[count], opal_index,
 483                                         sdata[count - 1].hwmon_index,
 484                                         sensor_id, attr_name, type,
 485                                         pgroups[type], show_sensor);
 486                         count++;
 487                 }
 488
 489                 if (!of_property_read_u32(np, "sensor-data-min", &sensor_id)) {
 490                         attr_name = get_min_attr(type);
 491                         populate_sensor(&sdata[count], opal_index,
 492                                         sdata[count - 1].hwmon_index,
 493                                         sensor_id, attr_name, type,
 494                                         pgroups[type], show_sensor);
 495                         count++;
 496                 }
 497         }
 498
 499 exit_put_node:
 500         of_node_put(opal);
 501         return err;
 502 }
 503
 504 static int ibmpowernv_probe(struct platform_device *pdev)
 505 {
 506         struct platform_data *pdata;
 507         struct device *hwmon_dev;
 508         int err;
 509
 510         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 511         if (!pdata)
 512                 return -ENOMEM;
 513
 514         platform_set_drvdata(pdev, pdata);
 515         pdata->sensors_count = 0;
 516         err = populate_attr_groups(pdev);
 517         if (err)
 518                 return err;
 519
 520         /* Create sysfs attribute data for each sensor found in the DT */
 521         err = create_device_attrs(pdev);
 522         if (err)
 523                 return err;
 524
 525         /* Finally, register with hwmon */
 526         hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
 527                                                            pdata,
 528                                                            pdata->attr_groups);
 529
 530         return PTR_ERR_OR_ZERO(hwmon_dev);
 531 }
 532
 533 static const struct platform_device_id opal_sensor_driver_ids[] = {
 534         {
 535                 .name = "opal-sensor",
 536         },
 537         { }
 538 };
 539 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
 540
 541 static const struct of_device_id opal_sensor_match[] = {
 542         { .compatible   = "ibm,opal-sensor" },
 543         { },
 544 };
 545 MODULE_DEVICE_TABLE(of, opal_sensor_match);
 546
 547 static struct platform_driver ibmpowernv_driver = {
 548         .probe          = ibmpowernv_probe,
 549         .id_table       = opal_sensor_driver_ids,
 550         .driver         = {
 551                 .name   = DRVNAME,
 552                 .of_match_table = opal_sensor_match,
 553         },
 554 };
 555
 556 module_platform_driver(ibmpowernv_driver);
 557
 558 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
 559 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
 560 MODULE_LICENSE("GPL");