drivers/hwmon/ibmpex.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * A hwmon driver for the IBM PowerExecutive temperature/power sensors
   4  * Copyright (C) 2007 IBM
   5  *
   6  * Author: Darrick J. Wong <darrick.wong@oracle.com>
   7  */
   8
   9 #include <linux/ipmi.h>
  10 #include <linux/module.h>
  11 #include <linux/hwmon.h>
  12 #include <linux/hwmon-sysfs.h>
  13 #include <linux/jiffies.h>
  14 #include <linux/mutex.h>
  15 #include <linux/slab.h>
  16 #include <linux/err.h>
  17
  18 #define REFRESH_INTERVAL        (2 * HZ)
  19 #define DRVNAME                 "ibmpex"
  20
  21 #define PEX_GET_VERSION         1
  22 #define PEX_GET_SENSOR_COUNT    2
  23 #define PEX_GET_SENSOR_NAME     3
  24 #define PEX_RESET_HIGH_LOW      4
  25 #define PEX_GET_SENSOR_DATA     6
  26
  27 #define PEX_NET_FUNCTION        0x3A
  28 #define PEX_COMMAND             0x3C
  29
  30 static inline u16 extract_value(const char *data, int offset)
  31 {
  32         return be16_to_cpup((__be16 *)&data[offset]);
  33 }
  34
  35 #define TEMP_SENSOR             1
  36 #define POWER_SENSOR            2
  37
  38 #define PEX_SENSOR_TYPE_LEN     3
  39 static u8 const power_sensor_sig[] = {0x70, 0x77, 0x72};
  40 static u8 const temp_sensor_sig[]  = {0x74, 0x65, 0x6D};
  41
  42 #define PEX_MULT_LEN            2
  43 static u8 const watt_sensor_sig[]  = {0x41, 0x43};
  44
  45 #define PEX_NUM_SENSOR_FUNCS    3
  46 static const char * const sensor_name_suffixes[] = {
  47         "",
  48         "_lowest",
  49         "_highest"
  50 };
  51
  52 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
  53 static void ibmpex_register_bmc(int iface, struct device *dev);
  54 static void ibmpex_bmc_gone(int iface);
  55
  56 struct ibmpex_sensor_data {
  57         int                     in_use;
  58         s16                     values[PEX_NUM_SENSOR_FUNCS];
  59         int                     multiplier;
  60
  61         struct sensor_device_attribute_2        attr[PEX_NUM_SENSOR_FUNCS];
  62 };
  63
  64 struct ibmpex_bmc_data {
  65         struct list_head        list;
  66         struct device           *hwmon_dev;
  67         struct device           *bmc_device;
  68         struct mutex            lock;
  69         bool                    valid;
  70         unsigned long           last_updated;   /* In jiffies */
  71
  72         struct ipmi_addr        address;
  73         struct completion       read_complete;
  74         struct ipmi_user        *user;
  75         int                     interface;
  76
  77         struct kernel_ipmi_msg  tx_message;
  78         unsigned char           tx_msg_data[IPMI_MAX_MSG_LENGTH];
  79         long                    tx_msgid;
  80
  81         unsigned char           rx_msg_data[IPMI_MAX_MSG_LENGTH];
  82         unsigned long           rx_msg_len;
  83         unsigned char           rx_result;
  84         int                     rx_recv_type;
  85
  86         unsigned char           sensor_major;
  87         unsigned char           sensor_minor;
  88
  89         unsigned char           num_sensors;
  90         struct ibmpex_sensor_data       *sensors;
  91 };
  92
  93 struct ibmpex_driver_data {
  94         struct list_head        bmc_data;
  95         struct ipmi_smi_watcher bmc_events;
  96         struct ipmi_user_hndl   ipmi_hndlrs;
  97 };
  98
  99 static struct ibmpex_driver_data driver_data = {
 100         .bmc_data = LIST_HEAD_INIT(driver_data.bmc_data),
 101         .bmc_events = {
 102                 .owner = THIS_MODULE,
 103                 .new_smi = ibmpex_register_bmc,
 104                 .smi_gone = ibmpex_bmc_gone,
 105         },
 106         .ipmi_hndlrs = {
 107                 .ipmi_recv_hndl = ibmpex_msg_handler,
 108         },
 109 };
 110
 111 static int ibmpex_send_message(struct ibmpex_bmc_data *data)
 112 {
 113         int err;
 114
 115         err = ipmi_validate_addr(&data->address, sizeof(data->address));
 116         if (err)
 117                 goto out;
 118
 119         data->tx_msgid++;
 120         err = ipmi_request_settime(data->user, &data->address, data->tx_msgid,
 121                                    &data->tx_message, data, 0, 0, 0);
 122         if (err)
 123                 goto out1;
 124
 125         return 0;
 126 out1:
 127         dev_err(data->bmc_device, "request_settime=%x\n", err);
 128         return err;
 129 out:
 130         dev_err(data->bmc_device, "validate_addr=%x\n", err);
 131         return err;
 132 }
 133
 134 static int ibmpex_ver_check(struct ibmpex_bmc_data *data)
 135 {
 136         data->tx_msg_data[0] = PEX_GET_VERSION;
 137         data->tx_message.data_len = 1;
 138         ibmpex_send_message(data);
 139
 140         wait_for_completion(&data->read_complete);
 141
 142         if (data->rx_result || data->rx_msg_len != 6)
 143                 return -ENOENT;
 144
 145         data->sensor_major = data->rx_msg_data[0];
 146         data->sensor_minor = data->rx_msg_data[1];
 147
 148         dev_info(data->bmc_device,
 149                  "Found BMC with sensor interface v%d.%d %d-%02d-%02d on interface %d\n",
 150                  data->sensor_major,
 151                  data->sensor_minor,
 152                  extract_value(data->rx_msg_data, 2),
 153                  data->rx_msg_data[4],
 154                  data->rx_msg_data[5],
 155                  data->interface);
 156
 157         return 0;
 158 }
 159
 160 static int ibmpex_query_sensor_count(struct ibmpex_bmc_data *data)
 161 {
 162         data->tx_msg_data[0] = PEX_GET_SENSOR_COUNT;
 163         data->tx_message.data_len = 1;
 164         ibmpex_send_message(data);
 165
 166         wait_for_completion(&data->read_complete);
 167
 168         if (data->rx_result || data->rx_msg_len != 1)
 169                 return -ENOENT;
 170
 171         return data->rx_msg_data[0];
 172 }
 173
 174 static int ibmpex_query_sensor_name(struct ibmpex_bmc_data *data, int sensor)
 175 {
 176         data->tx_msg_data[0] = PEX_GET_SENSOR_NAME;
 177         data->tx_msg_data[1] = sensor;
 178         data->tx_message.data_len = 2;
 179         ibmpex_send_message(data);
 180
 181         wait_for_completion(&data->read_complete);
 182
 183         if (data->rx_result || data->rx_msg_len < 1)
 184                 return -ENOENT;
 185
 186         return 0;
 187 }
 188
 189 static int ibmpex_query_sensor_data(struct ibmpex_bmc_data *data, int sensor)
 190 {
 191         data->tx_msg_data[0] = PEX_GET_SENSOR_DATA;
 192         data->tx_msg_data[1] = sensor;
 193         data->tx_message.data_len = 2;
 194         ibmpex_send_message(data);
 195
 196         wait_for_completion(&data->read_complete);
 197
 198         if (data->rx_result || data->rx_msg_len < 26) {
 199                 dev_err(data->bmc_device, "Error reading sensor %d.\n",
 200                         sensor);
 201                 return -ENOENT;
 202         }
 203
 204         return 0;
 205 }
 206
 207 static int ibmpex_reset_high_low_data(struct ibmpex_bmc_data *data)
 208 {
 209         data->tx_msg_data[0] = PEX_RESET_HIGH_LOW;
 210         data->tx_message.data_len = 1;
 211         ibmpex_send_message(data);
 212
 213         wait_for_completion(&data->read_complete);
 214
 215         return 0;
 216 }
 217
 218 static void ibmpex_update_device(struct ibmpex_bmc_data *data)
 219 {
 220         int i, err;
 221
 222         mutex_lock(&data->lock);
 223         if (time_before(jiffies, data->last_updated + REFRESH_INTERVAL) &&
 224             data->valid)
 225                 goto out;
 226
 227         for (i = 0; i < data->num_sensors; i++) {
 228                 if (!data->sensors[i].in_use)
 229                         continue;
 230                 err = ibmpex_query_sensor_data(data, i);
 231                 if (err)
 232                         continue;
 233                 data->sensors[i].values[0] =
 234                         extract_value(data->rx_msg_data, 16);
 235                 data->sensors[i].values[1] =
 236                         extract_value(data->rx_msg_data, 18);
 237                 data->sensors[i].values[2] =
 238                         extract_value(data->rx_msg_data, 20);
 239         }
 240
 241         data->last_updated = jiffies;
 242         data->valid = true;
 243
 244 out:
 245         mutex_unlock(&data->lock);
 246 }
 247
 248 static struct ibmpex_bmc_data *get_bmc_data(int iface)
 249 {
 250         struct ibmpex_bmc_data *p, *next;
 251
 252         list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
 253                 if (p->interface == iface)
 254                         return p;
 255
 256         return NULL;
 257 }
 258
 259 static DEVICE_STRING_ATTR_RO(name, 0444, DRVNAME);
 260
 261 static ssize_t ibmpex_show_sensor(struct device *dev,
 262                                   struct device_attribute *devattr,
 263                                   char *buf)
 264 {
 265         struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(devattr);
 266         struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
 267         int mult = data->sensors[attr->index].multiplier;
 268         ibmpex_update_device(data);
 269
 270         return sprintf(buf, "%d\n",
 271                        data->sensors[attr->index].values[attr->nr] * mult);
 272 }
 273
 274 static ssize_t ibmpex_high_low_store(struct device *dev,
 275                                      struct device_attribute *devattr,
 276                                      const char *buf, size_t count)
 277 {
 278         struct ibmpex_bmc_data *data = dev_get_drvdata(dev);
 279
 280         ibmpex_reset_high_low_data(data);
 281
 282         return count;
 283 }
 284
 285 static SENSOR_DEVICE_ATTR_WO(reset_high_low, ibmpex_high_low, 0);
 286
 287 static int is_power_sensor(const char *sensor_id, int len)
 288 {
 289         if (len < PEX_SENSOR_TYPE_LEN)
 290                 return 0;
 291
 292         if (!memcmp(sensor_id, power_sensor_sig, PEX_SENSOR_TYPE_LEN))
 293                 return 1;
 294         return 0;
 295 }
 296
 297 static int is_temp_sensor(const char *sensor_id, int len)
 298 {
 299         if (len < PEX_SENSOR_TYPE_LEN)
 300                 return 0;
 301
 302         if (!memcmp(sensor_id, temp_sensor_sig, PEX_SENSOR_TYPE_LEN))
 303                 return 1;
 304         return 0;
 305 }
 306
 307 static int power_sensor_multiplier(struct ibmpex_bmc_data *data,
 308                                    const char *sensor_id, int len)
 309 {
 310         int i;
 311
 312         if (data->sensor_major == 2)
 313                 return 1000000;
 314
 315         for (i = PEX_SENSOR_TYPE_LEN; i < len - 1; i++)
 316                 if (!memcmp(&sensor_id[i], watt_sensor_sig, PEX_MULT_LEN))
 317                         return 1000000;
 318
 319         return 100000;
 320 }
 321
 322 static int create_sensor(struct ibmpex_bmc_data *data, int type,
 323                          int counter, int sensor, int func)
 324 {
 325         int err;
 326         char *n;
 327
 328         n = kmalloc(32, GFP_KERNEL);
 329         if (!n)
 330                 return -ENOMEM;
 331
 332         if (type == TEMP_SENSOR)
 333                 sprintf(n, "temp%d_input%s",
 334                         counter, sensor_name_suffixes[func]);
 335         else if (type == POWER_SENSOR)
 336                 sprintf(n, "power%d_average%s",
 337                         counter, sensor_name_suffixes[func]);
 338
 339         sysfs_attr_init(&data->sensors[sensor].attr[func].dev_attr.attr);
 340         data->sensors[sensor].attr[func].dev_attr.attr.name = n;
 341         data->sensors[sensor].attr[func].dev_attr.attr.mode = 0444;
 342         data->sensors[sensor].attr[func].dev_attr.show = ibmpex_show_sensor;
 343         data->sensors[sensor].attr[func].index = sensor;
 344         data->sensors[sensor].attr[func].nr = func;
 345
 346         err = device_create_file(data->bmc_device,
 347                                  &data->sensors[sensor].attr[func].dev_attr);
 348         if (err) {
 349                 data->sensors[sensor].attr[func].dev_attr.attr.name = NULL;
 350                 kfree(n);
 351                 return err;
 352         }
 353
 354         return 0;
 355 }
 356
 357 static int ibmpex_find_sensors(struct ibmpex_bmc_data *data)
 358 {
 359         int i, j, err;
 360         int sensor_type;
 361         int sensor_counter;
 362         int num_power = 0;
 363         int num_temp = 0;
 364
 365         err = ibmpex_query_sensor_count(data);
 366         if (err <= 0)
 367                 return -ENOENT;
 368         data->num_sensors = err;
 369
 370         data->sensors = kcalloc(data->num_sensors, sizeof(*data->sensors),
 371                                 GFP_KERNEL);
 372         if (!data->sensors)
 373                 return -ENOMEM;
 374
 375         for (i = 0; i < data->num_sensors; i++) {
 376                 err = ibmpex_query_sensor_name(data, i);
 377                 if (err)
 378                         continue;
 379
 380                 if (is_power_sensor(data->rx_msg_data, data->rx_msg_len)) {
 381                         sensor_type = POWER_SENSOR;
 382                         num_power++;
 383                         sensor_counter = num_power;
 384                         data->sensors[i].multiplier =
 385                                 power_sensor_multiplier(data,
 386                                                         data->rx_msg_data,
 387                                                         data->rx_msg_len);
 388                 } else if (is_temp_sensor(data->rx_msg_data,
 389                                           data->rx_msg_len)) {
 390                         sensor_type = TEMP_SENSOR;
 391                         num_temp++;
 392                         sensor_counter = num_temp;
 393                         data->sensors[i].multiplier = 1000;
 394                 } else
 395                         continue;
 396
 397                 data->sensors[i].in_use = 1;
 398
 399                 /* Create attributes */
 400                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 401                         err = create_sensor(data, sensor_type, sensor_counter,
 402                                             i, j);
 403                         if (err)
 404                                 goto exit_remove;
 405                 }
 406         }
 407
 408         err = device_create_file(data->bmc_device,
 409                         &sensor_dev_attr_reset_high_low.dev_attr);
 410         if (err)
 411                 goto exit_remove;
 412
 413         err = device_create_file(data->bmc_device, &dev_attr_name.attr);
 414         if (err)
 415                 goto exit_remove;
 416
 417         return 0;
 418
 419 exit_remove:
 420         device_remove_file(data->bmc_device,
 421                            &sensor_dev_attr_reset_high_low.dev_attr);
 422         device_remove_file(data->bmc_device, &dev_attr_name.attr);
 423         for (i = 0; i < data->num_sensors; i++)
 424                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 425                         if (!data->sensors[i].attr[j].dev_attr.attr.name)
 426                                 continue;
 427                         device_remove_file(data->bmc_device,
 428                                 &data->sensors[i].attr[j].dev_attr);
 429                         kfree(data->sensors[i].attr[j].dev_attr.attr.name);
 430                 }
 431
 432         kfree(data->sensors);
 433         return err;
 434 }
 435
 436 static void ibmpex_register_bmc(int iface, struct device *dev)
 437 {
 438         struct ibmpex_bmc_data *data;
 439         int err;
 440
 441         data = kzalloc(sizeof(*data), GFP_KERNEL);
 442         if (!data)
 443                 return;
 444
 445         data->address.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
 446         data->address.channel = IPMI_BMC_CHANNEL;
 447         data->address.data[0] = 0;
 448         data->interface = iface;
 449         data->bmc_device = dev;
 450
 451         /* Create IPMI messaging interface user */
 452         err = ipmi_create_user(data->interface, &driver_data.ipmi_hndlrs,
 453                                data, &data->user);
 454         if (err < 0) {
 455                 dev_err(dev,
 456                         "Unable to register user with IPMI interface %d\n",
 457                         data->interface);
 458                 goto out;
 459         }
 460
 461         mutex_init(&data->lock);
 462
 463         /* Initialize message */
 464         data->tx_msgid = 0;
 465         init_completion(&data->read_complete);
 466         data->tx_message.netfn = PEX_NET_FUNCTION;
 467         data->tx_message.cmd = PEX_COMMAND;
 468         data->tx_message.data = data->tx_msg_data;
 469
 470         /* Does this BMC support PowerExecutive? */
 471         err = ibmpex_ver_check(data);
 472         if (err)
 473                 goto out_user;
 474
 475         /* Register the BMC as a HWMON class device */
 476         data->hwmon_dev = hwmon_device_register(data->bmc_device);
 477
 478         if (IS_ERR(data->hwmon_dev)) {
 479                 dev_err(data->bmc_device,
 480                         "Unable to register hwmon device for IPMI interface %d\n",
 481                         data->interface);
 482                 goto out_user;
 483         }
 484
 485         /* finally add the new bmc data to the bmc data list */
 486         dev_set_drvdata(dev, data);
 487         list_add_tail(&data->list, &driver_data.bmc_data);
 488
 489         /* Now go find all the sensors */
 490         err = ibmpex_find_sensors(data);
 491         if (err) {
 492                 dev_err(data->bmc_device, "Error %d finding sensors\n", err);
 493                 goto out_register;
 494         }
 495
 496         return;
 497
 498 out_register:
 499         list_del(&data->list);
 500         hwmon_device_unregister(data->hwmon_dev);
 501 out_user:
 502         ipmi_destroy_user(data->user);
 503 out:
 504         kfree(data);
 505 }
 506
 507 static void ibmpex_bmc_delete(struct ibmpex_bmc_data *data)
 508 {
 509         int i, j;
 510
 511         device_remove_file(data->bmc_device,
 512                            &sensor_dev_attr_reset_high_low.dev_attr);
 513         device_remove_file(data->bmc_device, &dev_attr_name.attr);
 514         for (i = 0; i < data->num_sensors; i++)
 515                 for (j = 0; j < PEX_NUM_SENSOR_FUNCS; j++) {
 516                         if (!data->sensors[i].attr[j].dev_attr.attr.name)
 517                                 continue;
 518                         device_remove_file(data->bmc_device,
 519                                 &data->sensors[i].attr[j].dev_attr);
 520                         kfree(data->sensors[i].attr[j].dev_attr.attr.name);
 521                 }
 522
 523         list_del(&data->list);
 524         dev_set_drvdata(data->bmc_device, NULL);
 525         hwmon_device_unregister(data->hwmon_dev);
 526         ipmi_destroy_user(data->user);
 527         kfree(data->sensors);
 528         kfree(data);
 529 }
 530
 531 static void ibmpex_bmc_gone(int iface)
 532 {
 533         struct ibmpex_bmc_data *data = get_bmc_data(iface);
 534
 535         if (!data)
 536                 return;
 537
 538         ibmpex_bmc_delete(data);
 539 }
 540
 541 static void ibmpex_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
 542 {
 543         struct ibmpex_bmc_data *data = user_msg_data;
 544
 545         if (msg->msgid != data->tx_msgid) {
 546                 dev_err(data->bmc_device,
 547                         "Mismatch between received msgid (%02x) and transmitted msgid (%02x)!\n",
 548                         (int)msg->msgid,
 549                         (int)data->tx_msgid);
 550                 ipmi_free_recv_msg(msg);
 551                 return;
 552         }
 553
 554         data->rx_recv_type = msg->recv_type;
 555         if (msg->msg.data_len > 0)
 556                 data->rx_result = msg->msg.data[0];
 557         else
 558                 data->rx_result = IPMI_UNKNOWN_ERR_COMPLETION_CODE;
 559
 560         if (msg->msg.data_len > 1) {
 561                 data->rx_msg_len = msg->msg.data_len - 1;
 562                 memcpy(data->rx_msg_data, msg->msg.data + 1, data->rx_msg_len);
 563         } else
 564                 data->rx_msg_len = 0;
 565
 566         ipmi_free_recv_msg(msg);
 567         complete(&data->read_complete);
 568 }
 569
 570 static int __init ibmpex_init(void)
 571 {
 572         return ipmi_smi_watcher_register(&driver_data.bmc_events);
 573 }
 574
 575 static void __exit ibmpex_exit(void)
 576 {
 577         struct ibmpex_bmc_data *p, *next;
 578
 579         ipmi_smi_watcher_unregister(&driver_data.bmc_events);
 580         list_for_each_entry_safe(p, next, &driver_data.bmc_data, list)
 581                 ibmpex_bmc_delete(p);
 582 }
 583
 584 MODULE_AUTHOR("Darrick J. Wong <darrick.wong@oracle.com>");
 585 MODULE_DESCRIPTION("IBM PowerExecutive power/temperature sensor driver");
 586 MODULE_LICENSE("GPL");
 587
 588 module_init(ibmpex_init);
 589 module_exit(ibmpex_exit);
 590
 591 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3350-*");
 592 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550-*");
 593 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650-*");
 594 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3655-*");
 595 MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3755-*");