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 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 make_sensor_label(struct device_node *np,
 129                               struct sensor_data *sdata, const char *label)
 130 {
 131         u32 id;
 132         size_t n;
 133
 134         n = snprintf(sdata->label, sizeof(sdata->label), "%s", label);
 135
 136         /*
 137          * Core temp pretty print
 138          */
 139         if (!of_property_read_u32(np, "ibm,pir", &id)) {
 140                 int cpuid = get_logical_cpu(id);
 141
 142                 if (cpuid >= 0)
 143                         /*
 144                          * The digital thermal sensors are associated
 145                          * with a core.
 146                          */
 147                         n += snprintf(sdata->label + n,
 148                                       sizeof(sdata->label) - n, " %d",
 149                                       cpuid);
 150                 else
 151                         n += snprintf(sdata->label + n,
 152                                       sizeof(sdata->label) - n, " phy%d", id);
 153         }
 154
 155         /*
 156          * Membuffer pretty print
 157          */
 158         if (!of_property_read_u32(np, "ibm,chip-id", &id))
 159                 n += snprintf(sdata->label + n, sizeof(sdata->label) - n,
 160                               " %d", id & 0xffff);
 161 }
 162
 163 static int get_sensor_index_attr(const char *name, u32 *index, char *attr)
 164 {
 165         char *hash_pos = strchr(name, '#');
 166         char buf[8] = { 0 };
 167         char *dash_pos;
 168         u32 copy_len;
 169         int err;
 170
 171         if (!hash_pos)
 172                 return -EINVAL;
 173
 174         dash_pos = strchr(hash_pos, '-');
 175         if (!dash_pos)
 176                 return -EINVAL;
 177
 178         copy_len = dash_pos - hash_pos - 1;
 179         if (copy_len >= sizeof(buf))
 180                 return -EINVAL;
 181
 182         strncpy(buf, hash_pos + 1, copy_len);
 183
 184         err = kstrtou32(buf, 10, index);
 185         if (err)
 186                 return err;
 187
 188         strncpy(attr, dash_pos + 1, MAX_ATTR_LEN);
 189
 190         return 0;
 191 }
 192
 193 static const char *convert_opal_attr_name(enum sensors type,
 194                                           const char *opal_attr)
 195 {
 196         const char *attr_name = NULL;
 197
 198         if (!strcmp(opal_attr, DT_FAULT_ATTR_SUFFIX)) {
 199                 attr_name = "fault";
 200         } else if (!strcmp(opal_attr, DT_DATA_ATTR_SUFFIX)) {
 201                 attr_name = "input";
 202         } else if (!strcmp(opal_attr, DT_THRESHOLD_ATTR_SUFFIX)) {
 203                 if (type == TEMP)
 204                         attr_name = "max";
 205                 else if (type == FAN)
 206                         attr_name = "min";
 207         }
 208
 209         return attr_name;
 210 }
 211
 212 /*
 213  * This function translates the DT node name into the 'hwmon' attribute name.
 214  * IBMPOWERNV device node appear like cooling-fan#2-data, amb-temp#1-thrs etc.
 215  * which need to be mapped as fan2_input, temp1_max respectively before
 216  * populating them inside hwmon device class.
 217  */
 218 static const char *parse_opal_node_name(const char *node_name,
 219                                         enum sensors type, u32 *index)
 220 {
 221         char attr_suffix[MAX_ATTR_LEN];
 222         const char *attr_name;
 223         int err;
 224
 225         err = get_sensor_index_attr(node_name, index, attr_suffix);
 226         if (err)
 227                 return ERR_PTR(err);
 228
 229         attr_name = convert_opal_attr_name(type, attr_suffix);
 230         if (!attr_name)
 231                 return ERR_PTR(-ENOENT);
 232
 233         return attr_name;
 234 }
 235
 236 static int get_sensor_type(struct device_node *np)
 237 {
 238         enum sensors type;
 239         const char *str;
 240
 241         for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 242                 if (of_device_is_compatible(np, sensor_groups[type].compatible))
 243                         return type;
 244         }
 245
 246         /*
 247          * Let's check if we have a newer device tree
 248          */
 249         if (!of_device_is_compatible(np, "ibm,opal-sensor"))
 250                 return MAX_SENSOR_TYPE;
 251
 252         if (of_property_read_string(np, "sensor-type", &str))
 253                 return MAX_SENSOR_TYPE;
 254
 255         for (type = 0; type < MAX_SENSOR_TYPE; type++)
 256                 if (!strcmp(str, sensor_groups[type].name))
 257                         return type;
 258
 259         return MAX_SENSOR_TYPE;
 260 }
 261
 262 static u32 get_sensor_hwmon_index(struct sensor_data *sdata,
 263                                   struct sensor_data *sdata_table, int count)
 264 {
 265         int i;
 266
 267         /*
 268          * We don't use the OPAL index on newer device trees
 269          */
 270         if (sdata->opal_index != INVALID_INDEX) {
 271                 for (i = 0; i < count; i++)
 272                         if (sdata_table[i].opal_index == sdata->opal_index &&
 273                             sdata_table[i].type == sdata->type)
 274                                 return sdata_table[i].hwmon_index;
 275         }
 276         return ++sensor_groups[sdata->type].hwmon_index;
 277 }
 278
 279 static int populate_attr_groups(struct platform_device *pdev)
 280 {
 281         struct platform_data *pdata = platform_get_drvdata(pdev);
 282         const struct attribute_group **pgroups = pdata->attr_groups;
 283         struct device_node *opal, *np;
 284         enum sensors type;
 285
 286         opal = of_find_node_by_path("/ibm,opal/sensors");
 287         for_each_child_of_node(opal, np) {
 288                 const char *label;
 289
 290                 if (np->name == NULL)
 291                         continue;
 292
 293                 type = get_sensor_type(np);
 294                 if (type == MAX_SENSOR_TYPE)
 295                         continue;
 296
 297                 sensor_groups[type].attr_count++;
 298
 299                 /*
 300                  * add a new attribute for labels
 301                  */
 302                 if (!of_property_read_string(np, "label", &label))
 303                         sensor_groups[type].attr_count++;
 304         }
 305
 306         of_node_put(opal);
 307
 308         for (type = 0; type < MAX_SENSOR_TYPE; type++) {
 309                 sensor_groups[type].group.attrs = devm_kzalloc(&pdev->dev,
 310                                         sizeof(struct attribute *) *
 311                                         (sensor_groups[type].attr_count + 1),
 312                                         GFP_KERNEL);
 313                 if (!sensor_groups[type].group.attrs)
 314                         return -ENOMEM;
 315
 316                 pgroups[type] = &sensor_groups[type].group;
 317                 pdata->sensors_count += sensor_groups[type].attr_count;
 318                 sensor_groups[type].attr_count = 0;
 319         }
 320
 321         return 0;
 322 }
 323
 324 static void create_hwmon_attr(struct sensor_data *sdata, const char *attr_name,
 325                               ssize_t (*show)(struct device *dev,
 326                                               struct device_attribute *attr,
 327                                               char *buf))
 328 {
 329         snprintf(sdata->name, MAX_ATTR_LEN, "%s%d_%s",
 330                  sensor_groups[sdata->type].name, sdata->hwmon_index,
 331                  attr_name);
 332
 333         sysfs_attr_init(&sdata->dev_attr.attr);
 334         sdata->dev_attr.attr.name = sdata->name;
 335         sdata->dev_attr.attr.mode = S_IRUGO;
 336         sdata->dev_attr.show = show;
 337 }
 338
 339 /*
 340  * Iterate through the device tree for each child of 'sensors' node, create
 341  * a sysfs attribute file, the file is named by translating the DT node name
 342  * to the name required by the higher 'hwmon' driver like fan1_input, temp1_max
 343  * etc..
 344  */
 345 static int create_device_attrs(struct platform_device *pdev)
 346 {
 347         struct platform_data *pdata = platform_get_drvdata(pdev);
 348         const struct attribute_group **pgroups = pdata->attr_groups;
 349         struct device_node *opal, *np;
 350         struct sensor_data *sdata;
 351         u32 sensor_id;
 352         enum sensors type;
 353         u32 count = 0;
 354         int err = 0;
 355
 356         opal = of_find_node_by_path("/ibm,opal/sensors");
 357         sdata = devm_kzalloc(&pdev->dev, pdata->sensors_count * sizeof(*sdata),
 358                              GFP_KERNEL);
 359         if (!sdata) {
 360                 err = -ENOMEM;
 361                 goto exit_put_node;
 362         }
 363
 364         for_each_child_of_node(opal, np) {
 365                 const char *attr_name;
 366                 u32 opal_index;
 367                 const char *label;
 368
 369                 if (np->name == NULL)
 370                         continue;
 371
 372                 type = get_sensor_type(np);
 373                 if (type == MAX_SENSOR_TYPE)
 374                         continue;
 375
 376                 /*
 377                  * Newer device trees use a "sensor-data" property
 378                  * name for input.
 379                  */
 380                 if (of_property_read_u32(np, "sensor-id", &sensor_id) &&
 381                     of_property_read_u32(np, "sensor-data", &sensor_id)) {
 382                         dev_info(&pdev->dev,
 383                                  "'sensor-id' missing in the node '%s'\n",
 384                                  np->name);
 385                         continue;
 386                 }
 387
 388                 sdata[count].id = sensor_id;
 389                 sdata[count].type = type;
 390
 391                 /*
 392                  * If we can not parse the node name, it means we are
 393                  * running on a newer device tree. We can just forget
 394                  * about the OPAL index and use a defaut value for the
 395                  * hwmon attribute name
 396                  */
 397                 attr_name = parse_opal_node_name(np->name, type, &opal_index);
 398                 if (IS_ERR(attr_name)) {
 399                         attr_name = "input";
 400                         opal_index = INVALID_INDEX;
 401                 }
 402
 403                 sdata[count].opal_index = opal_index;
 404                 sdata[count].hwmon_index =
 405                         get_sensor_hwmon_index(&sdata[count], sdata, count);
 406
 407                 create_hwmon_attr(&sdata[count], attr_name, show_sensor);
 408
 409                 pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 410                                 &sdata[count++].dev_attr.attr;
 411
 412                 if (!of_property_read_string(np, "label", &label)) {
 413                         /*
 414                          * For the label attribute, we can reuse the
 415                          * "properties" of the previous "input"
 416                          * attribute. They are related to the same
 417                          * sensor.
 418                          */
 419                         sdata[count].type = type;
 420                         sdata[count].opal_index = sdata[count - 1].opal_index;
 421                         sdata[count].hwmon_index = sdata[count - 1].hwmon_index;
 422
 423                         make_sensor_label(np, &sdata[count], label);
 424
 425                         create_hwmon_attr(&sdata[count], "label", show_label);
 426
 427                         pgroups[type]->attrs[sensor_groups[type].attr_count++] =
 428                                 &sdata[count++].dev_attr.attr;
 429                 }
 430         }
 431
 432 exit_put_node:
 433         of_node_put(opal);
 434         return err;
 435 }
 436
 437 static int ibmpowernv_probe(struct platform_device *pdev)
 438 {
 439         struct platform_data *pdata;
 440         struct device *hwmon_dev;
 441         int err;
 442
 443         pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
 444         if (!pdata)
 445                 return -ENOMEM;
 446
 447         platform_set_drvdata(pdev, pdata);
 448         pdata->sensors_count = 0;
 449         err = populate_attr_groups(pdev);
 450         if (err)
 451                 return err;
 452
 453         /* Create sysfs attribute data for each sensor found in the DT */
 454         err = create_device_attrs(pdev);
 455         if (err)
 456                 return err;
 457
 458         /* Finally, register with hwmon */
 459         hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, DRVNAME,
 460                                                            pdata,
 461                                                            pdata->attr_groups);
 462
 463         return PTR_ERR_OR_ZERO(hwmon_dev);
 464 }
 465
 466 static const struct platform_device_id opal_sensor_driver_ids[] = {
 467         {
 468                 .name = "opal-sensor",
 469         },
 470         { }
 471 };
 472 MODULE_DEVICE_TABLE(platform, opal_sensor_driver_ids);
 473
 474 static const struct of_device_id opal_sensor_match[] = {
 475         { .compatible   = "ibm,opal-sensor" },
 476         { },
 477 };
 478 MODULE_DEVICE_TABLE(of, opal_sensor_match);
 479
 480 static struct platform_driver ibmpowernv_driver = {
 481         .probe          = ibmpowernv_probe,
 482         .id_table       = opal_sensor_driver_ids,
 483         .driver         = {
 484                 .name   = DRVNAME,
 485                 .of_match_table = opal_sensor_match,
 486         },
 487 };
 488
 489 module_platform_driver(ibmpowernv_driver);
 490
 491 MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
 492 MODULE_DESCRIPTION("IBM POWERNV platform sensors");
 493 MODULE_LICENSE("GPL");