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