drivers/hwmon/ibmpex.c

   1 /*
   2  * A hwmon driver for the IBM PowerExecutive temperature/power sensors
   3  * Copyright (C) 2007 IBM
   4  *
   5  * Author: Darrick J. Wong <djwong@us.ibm.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22 #include <linux/ipmi.h>
  23 #include <linux/module.h>
  24 #include <linux/hwmon.h>
  25 #include <linux/hwmon-sysfs.h>
  26 #include <linux/jiffies.h>
  27 #include <linux/mutex.h>
  28
  29 #define REFRESH_INTERVAL        (2 * HZ)
  30 #define DRVNAME                 "ibmpex"
  31
  32 #define PEX_GET_VERSION         1
  33 #define PEX_GET_SENSOR_COUNT    2
  34 #define PEX_GET_SENSOR_NAME     3
  35 #define PEX_RESET_HIGH_LOW      4
  36 #define PEX_GET_SENSOR_DATA     6
  37
  38 #define PEX_NET_FUNCTION        0x3A
  39 #define PEX_COMMAND             0x3C
  40
  41 static inline u16 extract_value(const char *data, int offset)
  42 {
  43         return be16_to_cpup((u16 *)&data[offset]);
  44 }
  45
  46 #define TEMP_SENSOR             1
  47 #define POWER_SENSOR            2
  48
  49 #define PEX_SENSOR_TYPE_LEN     3
  50 static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
  51 static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
  52
  53 #define PEX_MULT_LEN            2
  54 static u8 const watt_sensor_sig[]  = {0x41, 0x43};
  55
  56 #define PEX_NUM_SENSOR_FUNCS    3
  57 static char const * const power_sensor_name_templates[] = {
  58         "%s%d_average",
  59         "%s%d_average_lowest",
  60         "%s%d_average_highest"
  61 };
  62 static char const * const temp_sensor_name_templates[] = {
  63         "%s%d_input",
  64         "%s%d_input_lowest",
  65         "%s%d_input_highest"
  66 };
  67
  68 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
  69 static void ibmpex_register_bmc(int iface, struct device *dev);
  70 static void ibmpex_bmc_gone(int iface);
  71
  72 struct ibmpex_sensor_data {
  73         int                     in_use;
  74         s16                     values[PEX_NUM_SENSOR_FUNCS];
  75         int                     multiplier;
  76
  77         struct sensor_device_attribute_2        attr[PEX_NUM_SENSOR_FUNCS];
  78 };
  79
  80 struct ibmpex_bmc_data {
  81         struct list_head        list;
  82         struct device           *hwmon_dev;
  83         struct device           *bmc_device;
  84         struct mutex            lock;
  85         char                    valid;
  86         unsigned long           last_updated;   /* In jiffies */
  87
  88         struct ipmi_addr        address;
  89         struct completion       read_complete;
  90         ipmi_user_t             user;
  91         int                     interface;
  92
  93         struct kernel_ipmi_msg  tx_message;
  94         unsigned char           tx_msg_data[IPMI_MAX_MSG_LENGTH];
  95         long                    tx_msgid;
  96
  97         unsigned char           rx_msg_data[IPMI_MAX_MSG_LENGTH];
  98         unsigned long           rx_msg_len;
  99         unsigned char           rx_result;
 100         int                     rx_recv_type;
 101
 102         unsigned char           sensor_major;
 103         unsigned char           sensor_minor;
 104
 105         unsigned char           num_sensors;
 106         struct ibmpex_sensor_data       *sensors;
 107 };
 108
 109 struct ibmpex_driver_data {
 110         struct list_head        bmc_data;
 111         struct ipmi_smi_watcher bmc_events;
 112         struct ipmi_user_hndl   ipmi_hndlrs;
 113 };
 114
 115 static struct ibmpex_driver_data driver_data = {
 116         .bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
 117         .bmc_events = {
 118                 .owner = THIS_MODULE,
 119                 .new_smi = ibmpex_register_bmc,
 120                 .smi_gone = ibmpex_bmc_gone,
 121         },
 122         .ipmi_hndlrs = {
 123                 .ipmi_recv_hndl = ibmpex_msg_handler,
 124         },
 125 };
 126
 127 static int ibmpex_send_message(struct ibmpex_bmc_data *data)
 128 {
 129         int err;
 130
 131         err = ipmi_validate_addr(&data->address, sizeof(data->address));
 132         if (err)
 133                 goto out;
 134
 135         data->tx_msgid++;
 136         err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
 137                                    &data->tx_message, data, 0, 0, 0);
 138         if (err)
 139                 goto out1;
 140
 141         return 0;
 142 out1:
 143         dev_err(data->bmc_device, "request_settime=%x\n", err);
 144         return err;
 145 out:
 146         dev_err(data->bmc_device, "validate_addr=%x\n", err);
 147         return err;
 148 }
 149
 150 static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
 151 {
 152         data->tx_msg_data[0] = PEX_GET_VERSION;
 153         data->tx_message.data_len = 1;
 154         ibmpex_send_message(data);
 155
 156         wait_for_completion(&data->read_complete);
 157
 158         if (data->rx_result || data->rx_msg_len != 6)
 159                 return -ENOENT;
 160
 161         data->sensor_major = data->rx_msg_data[0];
 162         data->sensor_minor = data->rx_msg_data[1];
 163
 164         dev_info(data->bmc_device, "Found BMC with sensor interface "
 165                  "v%d.%d %d-%02d-%02d on interface %d\n",
 166                  data->sensor_major,
 167                  data->sensor_minor,
 168                  extract_value(data->rx_msg_data, 2),
 169                  data->rx_msg_data[4],
 170                  data->rx_msg_data[5],
 171                  data->interface);
 172
 173         return 0;
 174 }
 175
 176 static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
 177 {
 178         data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
 179         data->tx_message.data_len = 1;
 180         ibmpex_send_message(data);
 181
 182         wait_for_completion(&data->read_complete);
 183
 184         if (data->rx_result || data->rx_msg_len != 1)
 185                 return -ENOENT;
 186
 187         return data->rx_msg_data[0];
 188 }
 189
 190 static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
 191 {
 192         data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
 193         data->tx_msg_data[1] = sensor;
 194         data->tx_message.data_len = 2;
 195         ibmpex_send_message(data);
 196
 197         wait_for_completion(&data->read_complete);
 198
 199         if (data->rx_result || data->rx_msg_len < 1)
 200                 return -ENOENT;
 201
 202         return 0;
 203 }
 204
 205 static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
 206 {
 207         data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
 208         data->tx_msg_data[1] = sensor;
 209         data->tx_message.data_len = 2;
 210         ibmpex_send_message(data);
 211
 212         wait_for_completion(&data->read_complete);
 213
 214         if (data->rx_result || data->rx_msg_len < 26) {
 215                 dev_err(data->bmc_device, "Error reading sensor %d.\n",
 216                         sensor);
 217                 return -ENOENT;
 218         }
 219
 220         return 0;
 221 }
 222
 223 static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
 224 {
 225         data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
 226         data->tx_message.data_len = 1;
 227         ibmpex_send_message(data);
 228
 229         wait_for_completion(&data->read_complete);
 230
 231         return 0;
 232 }
 233
 234 static void ibmpex_update_device(struct ibmpex_bmc_data *data)
 235 {
 236         int i, err;
 237
 238         mutex_lock(&data->lock);
 239         if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
 240             data->valid)
 241                 goto out;
 242
 243         for (i = 0; i < data->num_sensors; i++) {
 244                 if (!data->sensors[i].in_use)
 245                         continue;
 246                 err = ibmpex_query_sensor_data(data, i);
 247                 if (err)
 248                         continue;
 249                 data->sensors[i].values[0] =
 250                         extract_value(data->rx_msg_data, 16);
 251                 data->sensors[i].values[1] =
 252                         extract_value(data->rx_msg_data, 18);
 253                 data->sensors[i].values[2] =
 254                         extract_value(data->rx_msg_data, 20);
 255         }
 256
 257         data->last_updated = jiffies;
 258         data->valid = 1;
 259
 260 out:
 261         mutex_unlock(&data->lock);
 262 }
 263
 264 static struct ibmpex_bmc_data *get_bmc_data(int iface)
 265 {
 266         struct ibmpex_bmc_data *p, *next;
 267
 268         list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
 269                 if (p->interface == iface)
 270                         return p;
 271
 272         return NULL;
 273 }
 274
 275 static ssize_t show_name(struct device *dev, struct device_attribute *devattr,
 276                          char *buf)
 277 {
 278         return sprintf(buf, "%s\n", DRVNAME);
 279 }
 280 static SENSOR_DEVICE_ATTR(name, S_IRUGO, show_name, NULL, 0);
 281
 282 static ssize_t ibmpex_show_sensor(struct device *dev,
 283                                   struct device_attribute *devattr,
 284                                   char *buf)
 285 {
 286         struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
 287         struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
 288         int mult = data->sensors[attr->index].multiplier;
 289         ibmpex_update_device(data);
 290
 291         return sprintf(buf, "%d\n",
 292                        data->sensors[attr->index].values[attr->nr] * mult);
 293 }
 294
 295 static ssize_t ibmpex_reset_high_low(struct device *dev,
 296                                      struct device_attribute *devattr,
 297                                      const char *buf,
 298                                      size_t count)
 299 {
 300         struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
 301
 302         ibmpex_reset_high_low_data(data);
 303
 304         return count;
 305 }
 306
 307 static SENSOR_DEVICE_ATTR(reset_high_low, S_IWUSR, NULL,
 308                           ibmpex_reset_high_low, 0);
 309
 310 static int is_power_sensor(const char *sensor_id, int len)
 311 {
 312         if (len < PEX_SENSOR_TYPE_LEN)
 313                 return 0;
 314
 315         if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
 316                 return 1;
 317         return 0;
 318 }
 319
 320 static int is_temp_sensor(const char *sensor_id, int len)
 321 {
 322         if (len < PEX_SENSOR_TYPE_LEN)
 323                 return 0;
 324
 325         if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
 326                 return 1;
 327         return 0;
 328 }
 329
 330 static int power_sensor_multiplier(const char *sensor_id, int len)
 331 {
 332         int i;
 333
 334         for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
 335                 if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
 336                         return 1000000;
 337
 338         return 100000;
 339 }
 340
 341 static int create_sensor(struct ibmpex_bmc_data *data, int type,
 342                          int counter, int sensor, int func)
 343 {
 344         int err;
 345         char *n;
 346
 347         n = kmalloc(32, GFP_KERNEL);
 348         if (!n)
 349                 return -ENOMEM;
 350
 351         if (type == TEMP_SENSOR)
 352                 sprintf(n, temp_sensor_name_templates[func], "temp", counter);
 353         else if (type == POWER_SENSOR)
 354                 sprintf(n, power_sensor_name_templates[func], "power", counter);
 355
 356         data->sensors[sensor].attr[func].dev_attr.attr.name = n;
 357         data->sensors[sensor].attr[func].dev_attr.attr.mode = S_IRUGO;
 358         data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
 359         data->sensors[sensor].attr[func].index = sensor;
 360         data->sensors[sensor].attr[func].nr = func;
 361
 362         err = device_create_file(data->bmc_device,
 363                                  &data->sensors[sensor].attr[func].dev_attr);
 364         if (err) {
 365                 data->sensors[sensor].attr[func].dev_attr.attr.name = NULL;
 366                 kfree(n);
 367                 return err;
 368         }
 369
 370         return 0;
 371 }
 372
 373 static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
 374 {
 375         int i, j, err;
 376         int sensor_type;
 377         int sensor_counter;
 378         int num_power = 0;
 379         int num_temp = 0;
 380
 381         err = ibmpex_query_sensor_count(data);
 382         if (err <= 0)
 383                 return -ENOENT;
 384         data->num_sensors = err;
 385
 386         data->sensors = kzalloc(data->num_sensors * sizeof(*data->sensors),
 387                                 GFP_KERNEL);
 388         if (!data->sensors)
 389                 return -ENOMEM;
 390
 391         for (i = 0; i < data->num_sensors; i++) {
 392                 err = ibmpex_query_sensor_name(data, i);
 393                 if (err)
 394                         continue;
 395
 396                 if (is_power_sensor(data->rx_msg_data, data->rx_msg_len)) {
 397                         sensor_type = POWER_SENSOR;
 398                         num_power++;
 399                         sensor_counter = num_power;
 400                         data->sensors[i].multiplier =
 401                                 power_sensor_multiplier(data->rx_msg_data,
 402                                                      data->rx_msg_len);
 403                 } else if (is_temp_sensor(data->rx_msg_data,
 404                                           data->rx_msg_len)) {
 405                         sensor_type = TEMP_SENSOR;
 406                         num_temp++;
 407                         sensor_counter = num_temp;
 408                         data->sensors[i].multiplier = 1;
 409                 } else
 410                         continue;
 411
 412                 data->sensors[i].in_use = 1;
 413
 414                 /* Create attributes */
 415                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 416                         err = create_sensor(data, sensor_type, sensor_counter,
 417                                             i, j);
 418                         if (err)
 419                                 goto exit_remove;
 420                 }
 421         }
 422
 423         err = device_create_file(data->bmc_device,
 424                         &sensor_dev_attr_reset_high_low.dev_attr);
 425         if (err)
 426                 goto exit_remove;
 427
 428         err = device_create_file(data->bmc_device,
 429                         &sensor_dev_attr_name.dev_attr);
 430         if (err)
 431                 goto exit_remove;
 432
 433         return 0;
 434
 435 exit_remove:
 436         device_remove_file(data->bmc_device,
 437                            &sensor_dev_attr_reset_high_low.dev_attr);
 438         device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
 439         for (i = 0; i < data->num_sensors; i++)
 440                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 441                         if (!data->sensors[i].attr[j].dev_attr.attr.name)
 442                                 continue;
 443                         device_remove_file(data->bmc_device,
 444                                 &data->sensors[i].attr[j].dev_attr);
 445                         kfree(data->sensors[i].attr[j].dev_attr.attr.name);
 446                 }
 447
 448         kfree(data->sensors);
 449         return err;
 450 }
 451
 452 static void ibmpex_register_bmc(int iface, struct device *dev)
 453 {
 454         struct ibmpex_bmc_data *data;
 455         int err;
 456
 457         data = kzalloc(sizeof(*data), GFP_KERNEL);
 458         if (!data) {
 459                 dev_err(dev, "Insufficient memory for BMC interface.\n");
 460                 return;
 461         }
 462
 463         data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
 464         data->address.channel = IPMI_BMC_CHANNEL;
 465         data->address.data[0] = 0;
 466         data->interface = iface;
 467         data->bmc_device = dev;
 468
 469         /* Create IPMI messaging interface user */
 470         err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
 471                                data, &data->user);
 472         if (err < 0) {
 473                 dev_err(dev, "Unable to register user with IPMI "
 474                         "interface %d\n", data->interface);
 475                 goto out;
 476         }
 477
 478         mutex_init(&data->lock);
 479
 480         /* Initialize message */
 481         data->tx_msgid = 0;
 482         init_completion(&data->read_complete);
 483         data->tx_message.netfn = PEX_NET_FUNCTION;
 484         data->tx_message.cmd = PEX_COMMAND;
 485         data->tx_message.data = data->tx_msg_data;
 486
 487         /* Does this BMC support PowerExecutive? */
 488         err = ibmpex_ver_check(data);
 489         if (err)
 490                 goto out_user;
 491
 492         /* Register the BMC as a HWMON class device */
 493         data->hwmon_dev = hwmon_device_register(data->bmc_device);
 494
 495         if (IS_ERR(data->hwmon_dev)) {
 496                 dev_err(data->bmc_device, "Unable to register hwmon "
 497                         "device for IPMI interface %d\n",
 498                         data->interface);
 499                 goto out_user;
 500         }
 501
 502         /* finally add the new bmc data to the bmc data list */
 503         dev_set_drvdata(dev, data);
 504         list_add_tail(&data->list, &driver_data.bmc_data);
 505
 506         /* Now go find all the sensors */
 507         err = ibmpex_find_sensors(data);
 508         if (err) {
 509                 dev_err(data->bmc_device, "Error %d finding sensors\n", err);
 510                 goto out_register;
 511         }
 512
 513         return;
 514
 515 out_register:
 516         hwmon_device_unregister(data->hwmon_dev);
 517 out_user:
 518         ipmi_destroy_user(data->user);
 519 out:
 520         kfree(data);
 521 }
 522
 523 static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
 524 {
 525         int i, j;
 526
 527         device_remove_file(data->bmc_device,
 528                            &sensor_dev_attr_reset_high_low.dev_attr);
 529         device_remove_file(data->bmc_device, &sensor_dev_attr_name.dev_attr);
 530         for (i = 0; i < data->num_sensors; i++)
 531                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 532                         if (!data->sensors[i].attr[j].dev_attr.attr.name)
 533                                 continue;
 534                         device_remove_file(data->bmc_device,
 535                                 &data->sensors[i].attr[j].dev_attr);
 536                         kfree(data->sensors[i].attr[j].dev_attr.attr.name);
 537                 }
 538
 539         list_del(&data->list);
 540         dev_set_drvdata(data->bmc_device, NULL);
 541         hwmon_device_unregister(data->hwmon_dev);
 542         ipmi_destroy_user(data->user);
 543         kfree(data->sensors);
 544         kfree(data);
 545 }
 546
 547 static void ibmpex_bmc_gone(int iface)
 548 {
 549         struct ibmpex_bmc_data *data = get_bmc_data(iface);
 550
 551         if (!data)
 552                 return;
 553
 554         ibmpex_bmc_delete(data);
 555 }
 556
 557 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
 558 {
 559         struct ibmpex_bmc_data *data = (struct ibmpex_bmc_data *)user_msg_data;
 560
 561         if (msg->msgid != data->tx_msgid) {
 562                 dev_err(data->bmc_device, "Mismatch between received msgid "
 563                         "(%02x) and transmitted msgid (%02x)!\n",
 564                         (int)msg->msgid,
 565                         (int)data->tx_msgid);
 566                 ipmi_free_recv_msg(msg);
 567                 return;
 568         }
 569
 570         data->rx_recv_type = msg->recv_type;
 571         if (msg->msg.data_len > 0)
 572                 data->rx_result = msg->msg.data[0];
 573         else
 574                 data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
 575
 576         if (msg->msg.data_len > 1) {
 577                 data->rx_msg_len = msg->msg.data_len - 1;
 578                 memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
 579         } else
 580                 data->rx_msg_len = 0;
 581
 582         ipmi_free_recv_msg(msg);
 583         complete(&data->read_complete);
 584 }
 585
 586 static int __init ibmpex_init(void)
 587 {
 588         return ipmi_smi_watcher_register(&driver_data.bmc_events);
 589 }
 590
 591 static void __exit ibmpex_exit(void)
 592 {
 593         struct ibmpex_bmc_data *p, *next;
 594
 595         ipmi_smi_watcher_unregister(&driver_data.bmc_events);
 596         list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
 597                 ibmpex_bmc_delete(p);
 598 }
 599
 600 MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
 601 MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
 602 MODULE_LICENSE("GPL");
 603
 604 module_init(ibmpex_init);
 605 module_exit(ibmpex_exit);