drivers/hwmon/pmbus/ibm-cffps.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright 2017 IBM Corp.
   4  */
   5
   6 #include <linux/bitfield.h>
   7 #include <linux/bitops.h>
   8 #include <linux/debugfs.h>
   9 #include <linux/device.h>
  10 #include <linux/fs.h>
  11 #include <linux/i2c.h>
  12 #include <linux/jiffies.h>
  13 #include <linux/leds.h>
  14 #include <linux/module.h>
  15 #include <linux/mutex.h>
  16 #include <linux/of_device.h>
  17 #include <linux/pmbus.h>
  18
  19 #include "pmbus.h"
  20
  21 #define CFFPS_FRU_CMD                           0x9A
  22 #define CFFPS_PN_CMD                            0x9B
  23 #define CFFPS_SN_CMD                            0x9E
  24 #define CFFPS_CCIN_CMD                          0xBD
  25 #define CFFPS_FW_CMD                            0xFA
  26 #define CFFPS1_FW_NUM_BYTES                     4
  27 #define CFFPS2_FW_NUM_WORDS                     3
  28 #define CFFPS_SYS_CONFIG_CMD                    0xDA
  29
  30 #define CFFPS_INPUT_HISTORY_CMD                 0xD6
  31 #define CFFPS_INPUT_HISTORY_SIZE                100
  32
  33 #define CFFPS_CCIN_VERSION                      GENMASK(15, 8)
  34 #define CFFPS_CCIN_VERSION_1                     0x2b
  35 #define CFFPS_CCIN_VERSION_2                     0x2e
  36
  37 /* STATUS_MFR_SPECIFIC bits */
  38 #define CFFPS_MFR_FAN_FAULT                     BIT(0)
  39 #define CFFPS_MFR_THERMAL_FAULT                 BIT(1)
  40 #define CFFPS_MFR_OV_FAULT                      BIT(2)
  41 #define CFFPS_MFR_UV_FAULT                      BIT(3)
  42 #define CFFPS_MFR_PS_KILL                       BIT(4)
  43 #define CFFPS_MFR_OC_FAULT                      BIT(5)
  44 #define CFFPS_MFR_VAUX_FAULT                    BIT(6)
  45 #define CFFPS_MFR_CURRENT_SHARE_WARNING         BIT(7)
  46
  47 /*
  48  * LED off state actually relinquishes LED control to PSU firmware, so it can
  49  * turn on the LED for faults.
  50  */
  51 #define CFFPS_LED_OFF                           0
  52 #define CFFPS_LED_BLINK                         BIT(0)
  53 #define CFFPS_LED_ON                            BIT(1)
  54 #define CFFPS_BLINK_RATE_MS                     250
  55
  56 enum {
  57         CFFPS_DEBUGFS_INPUT_HISTORY = 0,
  58         CFFPS_DEBUGFS_FRU,
  59         CFFPS_DEBUGFS_PN,
  60         CFFPS_DEBUGFS_SN,
  61         CFFPS_DEBUGFS_CCIN,
  62         CFFPS_DEBUGFS_FW,
  63         CFFPS_DEBUGFS_NUM_ENTRIES
  64 };
  65
  66 enum versions { cffps1, cffps2, cffps_unknown };
  67
  68 struct ibm_cffps_input_history {
  69         struct mutex update_lock;
  70         unsigned long last_update;
  71
  72         u8 byte_count;
  73         u8 data[CFFPS_INPUT_HISTORY_SIZE];
  74 };
  75
  76 struct ibm_cffps {
  77         enum versions version;
  78         struct i2c_client *client;
  79
  80         struct ibm_cffps_input_history input_history;
  81
  82         int debugfs_entries[CFFPS_DEBUGFS_NUM_ENTRIES];
  83
  84         char led_name[32];
  85         u8 led_state;
  86         struct led_classdev led;
  87 };
  88
  89 #define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])
  90
  91 static ssize_t ibm_cffps_read_input_history(struct ibm_cffps *psu,
  92                                             char __user *buf, size_t count,
  93                                             loff_t *ppos)
  94 {
  95         int rc;
  96         u8 msgbuf0[1] = { CFFPS_INPUT_HISTORY_CMD };
  97         u8 msgbuf1[CFFPS_INPUT_HISTORY_SIZE + 1] = { 0 };
  98         struct i2c_msg msg[2] = {
  99                 {
 100                         .addr = psu->client->addr,
 101                         .flags = psu->client->flags,
 102                         .len = 1,
 103                         .buf = msgbuf0,
 104                 }, {
 105                         .addr = psu->client->addr,
 106                         .flags = psu->client->flags | I2C_M_RD,
 107                         .len = CFFPS_INPUT_HISTORY_SIZE + 1,
 108                         .buf = msgbuf1,
 109                 },
 110         };
 111
 112         if (!*ppos) {
 113                 mutex_lock(&psu->input_history.update_lock);
 114                 if (time_after(jiffies, psu->input_history.last_update + HZ)) {
 115                         /*
 116                          * Use a raw i2c transfer, since we need more bytes
 117                          * than Linux I2C supports through smbus xfr (only 32).
 118                          */
 119                         rc = i2c_transfer(psu->client->adapter, msg, 2);
 120                         if (rc < 0) {
 121                                 mutex_unlock(&psu->input_history.update_lock);
 122                                 return rc;
 123                         }
 124
 125                         psu->input_history.byte_count = msgbuf1[0];
 126                         memcpy(psu->input_history.data, &msgbuf1[1],
 127                                CFFPS_INPUT_HISTORY_SIZE);
 128                         psu->input_history.last_update = jiffies;
 129                 }
 130
 131                 mutex_unlock(&psu->input_history.update_lock);
 132         }
 133
 134         return simple_read_from_buffer(buf, count, ppos,
 135                                        psu->input_history.data,
 136                                        psu->input_history.byte_count);
 137 }
 138
 139 static ssize_t ibm_cffps_debugfs_op(struct file *file, char __user *buf,
 140                                     size_t count, loff_t *ppos)
 141 {
 142         u8 cmd;
 143         int i, rc;
 144         int *idxp = file->private_data;
 145         int idx = *idxp;
 146         struct ibm_cffps *psu = to_psu(idxp, idx);
 147         char data[I2C_SMBUS_BLOCK_MAX] = { 0 };
 148
 149         pmbus_set_page(psu->client, 0);
 150
 151         switch (idx) {
 152         case CFFPS_DEBUGFS_INPUT_HISTORY:
 153                 return ibm_cffps_read_input_history(psu, buf, count, ppos);
 154         case CFFPS_DEBUGFS_FRU:
 155                 cmd = CFFPS_FRU_CMD;
 156                 break;
 157         case CFFPS_DEBUGFS_PN:
 158                 cmd = CFFPS_PN_CMD;
 159                 break;
 160         case CFFPS_DEBUGFS_SN:
 161                 cmd = CFFPS_SN_CMD;
 162                 break;
 163         case CFFPS_DEBUGFS_CCIN:
 164                 rc = i2c_smbus_read_word_swapped(psu->client, CFFPS_CCIN_CMD);
 165                 if (rc < 0)
 166                         return rc;
 167
 168                 rc = snprintf(data, 5, "%04X", rc);
 169                 goto done;
 170         case CFFPS_DEBUGFS_FW:
 171                 switch (psu->version) {
 172                 case cffps1:
 173                         for (i = 0; i < CFFPS1_FW_NUM_BYTES; ++i) {
 174                                 rc = i2c_smbus_read_byte_data(psu->client,
 175                                                               CFFPS_FW_CMD +
 176                                                                 i);
 177                                 if (rc < 0)
 178                                         return rc;
 179
 180                                 snprintf(&data[i * 2], 3, "%02X", rc);
 181                         }
 182
 183                         rc = i * 2;
 184                         break;
 185                 case cffps2:
 186                         for (i = 0; i < CFFPS2_FW_NUM_WORDS; ++i) {
 187                                 rc = i2c_smbus_read_word_data(psu->client,
 188                                                               CFFPS_FW_CMD +
 189                                                                 i);
 190                                 if (rc < 0)
 191                                         return rc;
 192
 193                                 snprintf(&data[i * 4], 5, "%04X", rc);
 194                         }
 195
 196                         rc = i * 4;
 197                         break;
 198                 default:
 199                         return -EOPNOTSUPP;
 200                 }
 201                 goto done;
 202         default:
 203                 return -EINVAL;
 204         }
 205
 206         rc = i2c_smbus_read_block_data(psu->client, cmd, data);
 207         if (rc < 0)
 208                 return rc;
 209
 210 done:
 211         data[rc] = '\n';
 212         rc += 2;
 213
 214         return simple_read_from_buffer(buf, count, ppos, data, rc);
 215 }
 216
 217 static const struct file_operations ibm_cffps_fops = {
 218         .llseek = noop_llseek,
 219         .read = ibm_cffps_debugfs_op,
 220         .open = simple_open,
 221 };
 222
 223 static int ibm_cffps_read_byte_data(struct i2c_client *client, int page,
 224                                     int reg)
 225 {
 226         int rc, mfr;
 227
 228         switch (reg) {
 229         case PMBUS_STATUS_VOUT:
 230         case PMBUS_STATUS_IOUT:
 231         case PMBUS_STATUS_TEMPERATURE:
 232         case PMBUS_STATUS_FAN_12:
 233                 rc = pmbus_read_byte_data(client, page, reg);
 234                 if (rc < 0)
 235                         return rc;
 236
 237                 mfr = pmbus_read_byte_data(client, page,
 238                                            PMBUS_STATUS_MFR_SPECIFIC);
 239                 if (mfr < 0)
 240                         /*
 241                          * Return the status register instead of an error,
 242                          * since we successfully read status.
 243                          */
 244                         return rc;
 245
 246                 /* Add MFR_SPECIFIC bits to the standard pmbus status regs. */
 247                 if (reg == PMBUS_STATUS_FAN_12) {
 248                         if (mfr & CFFPS_MFR_FAN_FAULT)
 249                                 rc |= PB_FAN_FAN1_FAULT;
 250                 } else if (reg == PMBUS_STATUS_TEMPERATURE) {
 251                         if (mfr & CFFPS_MFR_THERMAL_FAULT)
 252                                 rc |= PB_TEMP_OT_FAULT;
 253                 } else if (reg == PMBUS_STATUS_VOUT) {
 254                         if (mfr & (CFFPS_MFR_OV_FAULT | CFFPS_MFR_VAUX_FAULT))
 255                                 rc |= PB_VOLTAGE_OV_FAULT;
 256                         if (mfr & CFFPS_MFR_UV_FAULT)
 257                                 rc |= PB_VOLTAGE_UV_FAULT;
 258                 } else if (reg == PMBUS_STATUS_IOUT) {
 259                         if (mfr & CFFPS_MFR_OC_FAULT)
 260                                 rc |= PB_IOUT_OC_FAULT;
 261                         if (mfr & CFFPS_MFR_CURRENT_SHARE_WARNING)
 262                                 rc |= PB_CURRENT_SHARE_FAULT;
 263                 }
 264                 break;
 265         default:
 266                 rc = -ENODATA;
 267                 break;
 268         }
 269
 270         return rc;
 271 }
 272
 273 static int ibm_cffps_read_word_data(struct i2c_client *client, int page,
 274                                     int reg)
 275 {
 276         int rc, mfr;
 277
 278         switch (reg) {
 279         case PMBUS_STATUS_WORD:
 280                 rc = pmbus_read_word_data(client, page, reg);
 281                 if (rc < 0)
 282                         return rc;
 283
 284                 mfr = pmbus_read_byte_data(client, page,
 285                                            PMBUS_STATUS_MFR_SPECIFIC);
 286                 if (mfr < 0)
 287                         /*
 288                          * Return the status register instead of an error,
 289                          * since we successfully read status.
 290                          */
 291                         return rc;
 292
 293                 if (mfr & CFFPS_MFR_PS_KILL)
 294                         rc |= PB_STATUS_OFF;
 295                 break;
 296         default:
 297                 rc = -ENODATA;
 298                 break;
 299         }
 300
 301         return rc;
 302 }
 303
 304 static int ibm_cffps_led_brightness_set(struct led_classdev *led_cdev,
 305                                         enum led_brightness brightness)
 306 {
 307         int rc;
 308         u8 next_led_state;
 309         struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);
 310
 311         if (brightness == LED_OFF) {
 312                 next_led_state = CFFPS_LED_OFF;
 313         } else {
 314                 brightness = LED_FULL;
 315
 316                 if (psu->led_state != CFFPS_LED_BLINK)
 317                         next_led_state = CFFPS_LED_ON;
 318                 else
 319                         next_led_state = CFFPS_LED_BLINK;
 320         }
 321
 322         dev_dbg(&psu->client->dev, "LED brightness set: %d. Command: %d.\n",
 323                 brightness, next_led_state);
 324
 325         pmbus_set_page(psu->client, 0);
 326
 327         rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
 328                                        next_led_state);
 329         if (rc < 0)
 330                 return rc;
 331
 332         psu->led_state = next_led_state;
 333         led_cdev->brightness = brightness;
 334
 335         return 0;
 336 }
 337
 338 static int ibm_cffps_led_blink_set(struct led_classdev *led_cdev,
 339                                    unsigned long *delay_on,
 340                                    unsigned long *delay_off)
 341 {
 342         int rc;
 343         struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);
 344
 345         dev_dbg(&psu->client->dev, "LED blink set.\n");
 346
 347         pmbus_set_page(psu->client, 0);
 348
 349         rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
 350                                        CFFPS_LED_BLINK);
 351         if (rc < 0)
 352                 return rc;
 353
 354         psu->led_state = CFFPS_LED_BLINK;
 355         led_cdev->brightness = LED_FULL;
 356         *delay_on = CFFPS_BLINK_RATE_MS;
 357         *delay_off = CFFPS_BLINK_RATE_MS;
 358
 359         return 0;
 360 }
 361
 362 static void ibm_cffps_create_led_class(struct ibm_cffps *psu)
 363 {
 364         int rc;
 365         struct i2c_client *client = psu->client;
 366         struct device *dev = &client->dev;
 367
 368         snprintf(psu->led_name, sizeof(psu->led_name), "%s-%02x", client->name,
 369                  client->addr);
 370         psu->led.name = psu->led_name;
 371         psu->led.max_brightness = LED_FULL;
 372         psu->led.brightness_set_blocking = ibm_cffps_led_brightness_set;
 373         psu->led.blink_set = ibm_cffps_led_blink_set;
 374
 375         rc = devm_led_classdev_register(dev, &psu->led);
 376         if (rc)
 377                 dev_warn(dev, "failed to register led class: %d\n", rc);
 378 }
 379
 380 static struct pmbus_driver_info ibm_cffps_info[] = {
 381         [cffps1] = {
 382                 .pages = 1,
 383                 .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
 384                         PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_TEMP |
 385                         PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
 386                         PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
 387                         PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP |
 388                         PMBUS_HAVE_STATUS_FAN12,
 389                 .read_byte_data = ibm_cffps_read_byte_data,
 390                 .read_word_data = ibm_cffps_read_word_data,
 391         },
 392         [cffps2] = {
 393                 .pages = 2,
 394                 .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
 395                         PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_TEMP |
 396                         PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
 397                         PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
 398                         PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP |
 399                         PMBUS_HAVE_STATUS_FAN12,
 400                 .func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
 401                         PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
 402                         PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT,
 403                 .read_byte_data = ibm_cffps_read_byte_data,
 404                 .read_word_data = ibm_cffps_read_word_data,
 405         },
 406 };
 407
 408 static struct pmbus_platform_data ibm_cffps_pdata = {
 409         .flags = PMBUS_SKIP_STATUS_CHECK,
 410 };
 411
 412 static int ibm_cffps_probe(struct i2c_client *client,
 413                            const struct i2c_device_id *id)
 414 {
 415         int i, rc;
 416         enum versions vs = cffps_unknown;
 417         struct dentry *debugfs;
 418         struct dentry *ibm_cffps_dir;
 419         struct ibm_cffps *psu;
 420         const void *md = of_device_get_match_data(&client->dev);
 421
 422         if (md)
 423                 vs = (enum versions)md;
 424         else if (id)
 425                 vs = (enum versions)id->driver_data;
 426
 427         if (vs == cffps_unknown) {
 428                 u16 ccin_version = CFFPS_CCIN_VERSION_1;
 429                 int ccin = i2c_smbus_read_word_swapped(client, CFFPS_CCIN_CMD);
 430
 431                 if (ccin > 0)
 432                         ccin_version = FIELD_GET(CFFPS_CCIN_VERSION, ccin);
 433
 434                 switch (ccin_version) {
 435                 default:
 436                 case CFFPS_CCIN_VERSION_1:
 437                         vs = cffps1;
 438                         break;
 439                 case CFFPS_CCIN_VERSION_2:
 440                         vs = cffps2;
 441                         break;
 442                 }
 443
 444                 /* Set the client name to include the version number. */
 445                 snprintf(client->name, I2C_NAME_SIZE, "cffps%d", vs + 1);
 446         }
 447
 448         client->dev.platform_data = &ibm_cffps_pdata;
 449         rc = pmbus_do_probe(client, id, &ibm_cffps_info[vs]);
 450         if (rc)
 451                 return rc;
 452
 453         /*
 454          * Don't fail the probe if there isn't enough memory for leds and
 455          * debugfs.
 456          */
 457         psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
 458         if (!psu)
 459                 return 0;
 460
 461         psu->version = vs;
 462         psu->client = client;
 463         mutex_init(&psu->input_history.update_lock);
 464         psu->input_history.last_update = jiffies - HZ;
 465
 466         ibm_cffps_create_led_class(psu);
 467
 468         /* Don't fail the probe if we can't create debugfs */
 469         debugfs = pmbus_get_debugfs_dir(client);
 470         if (!debugfs)
 471                 return 0;
 472
 473         ibm_cffps_dir = debugfs_create_dir(client->name, debugfs);
 474         if (!ibm_cffps_dir)
 475                 return 0;
 476
 477         for (i = 0; i < CFFPS_DEBUGFS_NUM_ENTRIES; ++i)
 478                 psu->debugfs_entries[i] = i;
 479
 480         debugfs_create_file("input_history", 0444, ibm_cffps_dir,
 481                             &psu->debugfs_entries[CFFPS_DEBUGFS_INPUT_HISTORY],
 482                             &ibm_cffps_fops);
 483         debugfs_create_file("fru", 0444, ibm_cffps_dir,
 484                             &psu->debugfs_entries[CFFPS_DEBUGFS_FRU],
 485                             &ibm_cffps_fops);
 486         debugfs_create_file("part_number", 0444, ibm_cffps_dir,
 487                             &psu->debugfs_entries[CFFPS_DEBUGFS_PN],
 488                             &ibm_cffps_fops);
 489         debugfs_create_file("serial_number", 0444, ibm_cffps_dir,
 490                             &psu->debugfs_entries[CFFPS_DEBUGFS_SN],
 491                             &ibm_cffps_fops);
 492         debugfs_create_file("ccin", 0444, ibm_cffps_dir,
 493                             &psu->debugfs_entries[CFFPS_DEBUGFS_CCIN],
 494                             &ibm_cffps_fops);
 495         debugfs_create_file("fw_version", 0444, ibm_cffps_dir,
 496                             &psu->debugfs_entries[CFFPS_DEBUGFS_FW],
 497                             &ibm_cffps_fops);
 498
 499         return 0;
 500 }
 501
 502 static const struct i2c_device_id ibm_cffps_id[] = {
 503         { "ibm_cffps1", cffps1 },
 504         { "ibm_cffps2", cffps2 },
 505         { "ibm_cffps", cffps_unknown },
 506         {}
 507 };
 508 MODULE_DEVICE_TABLE(i2c, ibm_cffps_id);
 509
 510 static const struct of_device_id ibm_cffps_of_match[] = {
 511         {
 512                 .compatible = "ibm,cffps1",
 513                 .data = (void *)cffps1
 514         },
 515         {
 516                 .compatible = "ibm,cffps2",
 517                 .data = (void *)cffps2
 518         },
 519         {
 520                 .compatible = "ibm,cffps",
 521                 .data = (void *)cffps_unknown
 522         },
 523         {}
 524 };
 525 MODULE_DEVICE_TABLE(of, ibm_cffps_of_match);
 526
 527 static struct i2c_driver ibm_cffps_driver = {
 528         .driver = {
 529                 .name = "ibm-cffps",
 530                 .of_match_table = ibm_cffps_of_match,
 531         },
 532         .probe = ibm_cffps_probe,
 533         .remove = pmbus_do_remove,
 534         .id_table = ibm_cffps_id,
 535 };
 536
 537 module_i2c_driver(ibm_cffps_driver);
 538
 539 MODULE_AUTHOR("Eddie James");
 540 MODULE_DESCRIPTION("PMBus driver for IBM Common Form Factor power supplies");
 541 MODULE_LICENSE("GPL");