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. Let's print out the range of
 147                          * cpu ids corresponding to the hardware
 148                          * threads of the core.
 149                          */
 150                         n += snprintf(sdata->label + n,
 151                                       sizeof(sdata->label) - n, " %d-%d",
 152                                       cpuid, cpuid + threads_per_core - 1);
 153                 else
 154                         n += snprintf(sdata->label + n,
 155                                       sizeof(sdata->label) - n, " phy%d", id);
 156         }
 157
 158         /*
 159          * Membuffer pretty print
 160          */
 161         if (!of_property_read_u32(np, "ibm,chip-id", &id))
 162                 n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
 163                               " %d", id & 0xffff);
 164 }
 165
 166 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
 167 {
 168         char *hash_pos = strchr(name, '#');
 169         char buf[8] = { 0 };
 170         char *dash_pos;
 171         u32 copy_len;
 172         int err;
 173
 174         if (!hash_pos)
 175                 return -EINVAL;
 176
 177         dash_pos = strchr(hash_pos, '-');
 178         if (!dash_pos)
 179                 return -EINVAL;
 180
 181         copy_len = dash_pos - hash_pos - 1;
 182         if (copy_len >= sizeof(buf))
 183                 return -EINVAL;
 184
 185         strncpy(buf, hash_pos + 1, copy_len);
 186
 187         err = kstrtou32(buf, 10, index);
 188         if (err)
 189                 return err;
 190
 191         strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
 192
 193         return 0;
 194 }
 195
 196 static const char *convert_opal_attr_name(enum sensors type,
 197                                           const char *opal_attr)
 198 {
 199         const char *attr_name = NULL;
 200
 201         if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
 202                 attr_name = "fault";
 203         } else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
 204                 attr_name = "input";
 205         } else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
 206                 if (type == TEMP)
 207                         attr_name = "max";
 208                 else if (type == FAN)
 209                         attr_name = "min";
 210         }
 211
 212         return attr_name;
 213 }
 214
 215 /*
 216  * This function translates the DT node name into the 'hwmon' attribute name.
 217  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
 218  * which need to be mapped as fan2_input, temp1_max respectively before
 219  * populating them inside hwmon device class.
 220  */
 221 static const char *parse_opal_node_name(const char *node_name,
 222                                         enum sensors type, u32 *index)
 223 {
 224         char attr_suffix[MAX_ATTR_LEN];
 225         const char *attr_name;
 226         int err;
 227
 228         err = get_sensor_index_attr(node_name, index, attr_suffix);
 229         if (err)
 230                 return ERR_PTR(err);
 231
 232         attr_name = convert_opal_attr_name(type, attr_suffix);
 233         if (!attr_name)
 234                 return ERR_PTR(-ENOENT);
 235
 236         return attr_name;
 237 }
 238
 239 static int get_sensor_type(struct device_node *np)
 240 {
 241         enum sensors type;
 242         const char *str;
 243
 244         for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 245                 if (of_device_is_compatible(np, sensor_groups[type].compatible))
 246                         return type;
 247         }
 248
 249         /*
 250          * Let's check if we have a newer device tree
 251          */
 252         if (!of_device_is_compatible(np, "ibm,opal-sensor"))
 253                 return MAX_SENSOR_TYPE;
 254
 255         if (of_property_read_string(np, "sensor-type", &str))
 256                 return MAX_SENSOR_TYPE;
 257
 258         for (type = 0; type < MAX_SENSOR_TYPE; type++)
 259                 if (!strcmp(str, sensor_groups[type].name))
 260                         return type;
 261
 262         return MAX_SENSOR_TYPE;
 263 }
 264
 265 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
 266                                   struct sensor_data *sdata_table, int count)
 267 {
 268         int i;
 269
 270         /*
 271          * We don't use the OPAL index on newer device trees
 272          */
 273         if (sdata->opal_index != INVALID_INDEX) {
 274                 for (i = 0; i < count; i++)
 275                         if (sdata_table[i].opal_index == sdata->opal_index &&
 276                             sdata_table[i].type == sdata->type)
 277                                 return sdata_table[i].hwmon_index;
 278         }
 279         return ++sensor_groups[sdata->type].hwmon_index;
 280 }
 281
 282 static int populate_attr_groups(struct platform_device *pdev)
 283 {
 284         struct platform_data *pdata = platform_get_drvdata(pdev);
 285         const struct attribute_group **pgroups = pdata->attr_groups;
 286         struct device_node *opal, *np;
 287         enum sensors type;
 288
 289         opal = of_find_node_by_path("/ibm,opal/sensors");
 290         for_each_child_of_node(opal, np) {
 291                 const char *label;
 292
 293                 if (np->name == NULL)
 294                         continue;
 295
 296                 type = get_sensor_type(np);
 297                 if (type == MAX_SENSOR_TYPE)
 298                         continue;
 299
 300                 sensor_groups[type].attr_count++;
 301
 302                 /*
 303                  * add a new attribute for labels
 304                  */
 305                 if (!of_property_read_string(np, "label", &label))
 306                         sensor_groups[type].attr_count++;
 307         }
 308
 309         of_node_put(opal);
 310
 311         for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 312                 sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
 313                                         sizeof(struct attribute *) *
 314                                         (sensor_groups[type].attr_count + 1),
 315                                         GFP_KERNEL);
 316                 if (!sensor_groups[type].group.attrs)
 317                         return -ENOMEM;
 318
 319                 pgroups[type] = &sensor_groups[type].group;
 320                 pdata->sensors_count += sensor_groups[type].attr_count;
 321                 sensor_groups[type].attr_count = 0;
 322         }
 323
 324         return 0;
 325 }
 326
 327 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
 328                               ssize_t (*show)(struct device *dev,
 329                                               struct device_attribute *attr,
 330                                               char *buf))
 331 {
 332         snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
 333                  sensor_groups[sdata->type].name, sdata->hwmon_index,
 334                  attr_name);
 335
 336         sysfs_attr_init(&sdata->dev_attr.attr);
 337         sdata->dev_attr.attr.name = sdata->name;
 338         sdata->dev_attr.attr.mode = S_IRUGO;
 339         sdata->dev_attr.show = show;
 340 }
 341
 342 /*
 343  * Iterate through the device tree for each child of 'sensors' node, create
 344  * a sysfs attribute file, the file is named by translating the DT node name
 345  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
 346  * etc..
 347  */
 348 static int create_device_attrs(struct platform_device *pdev)
 349 {
 350         struct platform_data *pdata = platform_get_drvdata(pdev);
 351         const struct attribute_group **pgroups = pdata->attr_groups;
 352         struct device_node *opal, *np;
 353         struct sensor_data *sdata;
 354         u32 sensor_id;
 355         enum sensors type;
 356         u32 count = 0;
 357         int err = 0;
 358
 359         opal = of_find_node_by_path("/ibm,opal/sensors");
 360         sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
 361                              GFP_KERNEL);
 362         if (!sdata) {
 363                 err = -ENOMEM;
 364                 goto exit_put_node;
 365         }
 366
 367         for_each_child_of_node(opal, np) {
 368                 const char *attr_name;
 369                 u32 opal_index;
 370                 const char *label;
 371
 372                 if (np->name == NULL)
 373                         continue;
 374
 375                 type = get_sensor_type(np);
 376                 if (type == MAX_SENSOR_TYPE)
 377                         continue;
 378
 379                 /*
 380                  * Newer device trees use a "sensor-data" property
 381                  * name for input.
 382                  */
 383                 if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
 384                     of_property_read_u32(np, "sensor-data", &sensor_id)) {
 385                         dev_info(&pdev->dev,
 386                                  "'sensor-id' missing in the node '%s'\n",
 387                                  np->name);
 388                         continue;
 389                 }
 390
 391                 sdata[count].id = sensor_id;
 392                 sdata[count].type = type;
 393
 394                 /*
 395                  * If we can not parse the node name, it means we are
 396                  * running on a newer device tree. We can just forget
 397                  * about the OPAL index and use a defaut value for the
 398                  * hwmon attribute name
 399                  */
 400                 attr_name = parse_opal_node_name(np->name, type, &opal_index);
 401                 if (IS_ERR(attr_name)) {
 402                         attr_name = "input";
 403                         opal_index = INVALID_INDEX;
 404                 }
 405
 406                 sdata[count].opal_index = opal_index;
 407                 sdata[count].hwmon_index =
 408                         get_sensor_hwmon_index(&sdata[count], sdata, count);
 409
 410                 create_hwmon_attr(&sdata[count], attr_name, show_sensor);
 411
 412                 pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 413                                 &sdata[count++].dev_attr.attr;
 414
 415                 if (!of_property_read_string(np, "label", &label)) {
 416                         /*
 417                          * For the label attribute, we can reuse the
 418                          * "properties" of the previous "input"
 419                          * attribute. They are related to the same
 420                          * sensor.
 421                          */
 422                         sdata[count].type = type;
 423                         sdata[count].opal_index = sdata[count - 1].opal_index;
 424                         sdata[count].hwmon_index = sdata[count - 1].hwmon_index;
 425
 426                         make_sensor_label(np, &sdata[count], label);
 427
 428                         create_hwmon_attr(&sdata[count], "label", show_label);
 429
 430                         pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 431                                 &sdata[count++].dev_attr.attr;
 432                 }
 433         }
 434
 435 exit_put_node:
 436         of_node_put(opal);
 437         return err;
 438 }
 439
 440 static int ibmpowernv_probe(struct platform_device *pdev)
 441 {
 442         struct platform_data *pdata;
 443         struct device *hwmon_dev;
 444         int err;
 445
 446         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 447         if (!pdata)
 448                 return -ENOMEM;
 449
 450         platform_set_drvdata(pdev, pdata);
 451         pdata->sensors_count = 0;
 452         err = populate_attr_groups(pdev);
 453         if (err)
 454                 return err;
 455
 456         /* Create sysfs attribute data for each sensor found in the DT */
 457         err = create_device_attrs(pdev);
 458         if (err)
 459                 return err;
 460
 461         /* Finally, register with hwmon */
 462         hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
 463                                                            pdata,
 464                                                            pdata->attr_groups);
 465
 466         return PTR_ERR_OR_ZERO(hwmon_dev);
 467 }
 468
 469 static const struct platform_device_id opal_sensor_driver_ids[] = {
 470         {
 471                 .name = "opal-sensor",
 472         },
 473         { }
 474 };
 475 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
 476
 477 static const struct of_device_id opal_sensor_match[] = {
 478         { .compatible   = "ibm,opal-sensor" },
 479         { },
 480 };
 481 MODULE_DEVICE_TABLE(of, opal_sensor_match);
 482
 483 static struct platform_driver ibmpowernv_driver = {
 484         .probe          = ibmpowernv_probe,
 485         .id_table       = opal_sensor_driver_ids,
 486         .driver         = {
 487                 .name   = DRVNAME,
 488                 .of_match_table = opal_sensor_match,
 489         },
 490 };
 491
 492 module_platform_driver(ibmpowernv_driver);
 493
 494 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
 495 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
 496 MODULE_LICENSE("GPL");