drivers/hwmon/pmbus/max20730.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Driver for MAX20710, MAX20730, MAX20734, and MAX20743 Integrated,
   4  * Step-Down Switching Regulators
   5  *
   6  * Copyright 2019 Google LLC.
   7  * Copyright 2020 Maxim Integrated
   8  */
   9
  10 #include <linux/bits.h>
  11 #include <linux/debugfs.h>
  12 #include <linux/err.h>
  13 #include <linux/i2c.h>
  14 #include <linux/init.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/mutex.h>
  18 #include <linux/of.h>
  19 #include <linux/pmbus.h>
  20 #include <linux/util_macros.h>
  21 #include "pmbus.h"
  22
  23 enum chips {
  24         max20710,
  25         max20730,
  26         max20734,
  27         max20743
  28 };
  29
  30 enum {
  31         MAX20730_DEBUGFS_VOUT_MIN = 0,
  32         MAX20730_DEBUGFS_FREQUENCY,
  33         MAX20730_DEBUGFS_PG_DELAY,
  34         MAX20730_DEBUGFS_INTERNAL_GAIN,
  35         MAX20730_DEBUGFS_BOOT_VOLTAGE,
  36         MAX20730_DEBUGFS_OUT_V_RAMP_RATE,
  37         MAX20730_DEBUGFS_OC_PROTECT_MODE,
  38         MAX20730_DEBUGFS_SS_TIMING,
  39         MAX20730_DEBUGFS_IMAX,
  40         MAX20730_DEBUGFS_OPERATION,
  41         MAX20730_DEBUGFS_ON_OFF_CONFIG,
  42         MAX20730_DEBUGFS_SMBALERT_MASK,
  43         MAX20730_DEBUGFS_VOUT_MODE,
  44         MAX20730_DEBUGFS_VOUT_COMMAND,
  45         MAX20730_DEBUGFS_VOUT_MAX,
  46         MAX20730_DEBUGFS_NUM_ENTRIES
  47 };
  48
  49 struct max20730_data {
  50         enum chips id;
  51         struct pmbus_driver_info info;
  52         struct mutex lock;      /* Used to protect against parallel writes */
  53         u16 mfr_devset1;
  54         u16 mfr_devset2;
  55         u16 mfr_voutmin;
  56         u32 vout_voltage_divider[2];
  57 };
  58
  59 #define to_max20730_data(x)  container_of(x, struct max20730_data, info)
  60
  61 #define VOLT_FROM_REG(val)      DIV_ROUND_CLOSEST((val), 1 << 9)
  62
  63 #define PMBUS_SMB_ALERT_MASK    0x1B
  64
  65 #define MAX20730_MFR_VOUT_MIN   0xd1
  66 #define MAX20730_MFR_DEVSET1    0xd2
  67 #define MAX20730_MFR_DEVSET2    0xd3
  68
  69 #define MAX20730_MFR_VOUT_MIN_MASK              GENMASK(9, 0)
  70 #define MAX20730_MFR_VOUT_MIN_BIT_POS           0
  71
  72 #define MAX20730_MFR_DEVSET1_RGAIN_MASK         (BIT(13) | BIT(14))
  73 #define MAX20730_MFR_DEVSET1_OTP_MASK           (BIT(11) | BIT(12))
  74 #define MAX20730_MFR_DEVSET1_VBOOT_MASK         (BIT(8) | BIT(9))
  75 #define MAX20730_MFR_DEVSET1_OCP_MASK           (BIT(5) | BIT(6))
  76 #define MAX20730_MFR_DEVSET1_FSW_MASK           GENMASK(4, 2)
  77 #define MAX20730_MFR_DEVSET1_TSTAT_MASK         (BIT(0) | BIT(1))
  78
  79 #define MAX20730_MFR_DEVSET1_RGAIN_BIT_POS      13
  80 #define MAX20730_MFR_DEVSET1_OTP_BIT_POS        11
  81 #define MAX20730_MFR_DEVSET1_VBOOT_BIT_POS      8
  82 #define MAX20730_MFR_DEVSET1_OCP_BIT_POS        5
  83 #define MAX20730_MFR_DEVSET1_FSW_BIT_POS        2
  84 #define MAX20730_MFR_DEVSET1_TSTAT_BIT_POS      0
  85
  86 #define MAX20730_MFR_DEVSET2_IMAX_MASK          GENMASK(10, 8)
  87 #define MAX20730_MFR_DEVSET2_VRATE              (BIT(6) | BIT(7))
  88 #define MAX20730_MFR_DEVSET2_OCPM_MASK          BIT(5)
  89 #define MAX20730_MFR_DEVSET2_SS_MASK            (BIT(0) | BIT(1))
  90
  91 #define MAX20730_MFR_DEVSET2_IMAX_BIT_POS       8
  92 #define MAX20730_MFR_DEVSET2_VRATE_BIT_POS      6
  93 #define MAX20730_MFR_DEVSET2_OCPM_BIT_POS       5
  94 #define MAX20730_MFR_DEVSET2_SS_BIT_POS         0
  95
  96 #define DEBUG_FS_DATA_MAX                       16
  97
  98 struct max20730_debugfs_data {
  99         struct i2c_client *client;
 100         int debugfs_entries[MAX20730_DEBUGFS_NUM_ENTRIES];
 101 };
 102
 103 #define to_psu(x, y) container_of((x), \
 104                         struct max20730_debugfs_data, debugfs_entries[(y)])
 105
 106 #ifdef CONFIG_DEBUG_FS
 107 static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
 108                                      size_t count, loff_t *ppos)
 109 {
 110         int ret, len;
 111         int *idxp = file->private_data;
 112         int idx = *idxp;
 113         struct max20730_debugfs_data *psu = to_psu(idxp, idx);
 114         const struct pmbus_driver_info *info;
 115         const struct max20730_data *data;
 116         char tbuf[DEBUG_FS_DATA_MAX] = { 0 };
 117         char *result = tbuf;
 118         u16 val;
 119
 120         info = pmbus_get_driver_info(psu->client);
 121         data = to_max20730_data(info);
 122
 123         switch (idx) {
 124         case MAX20730_DEBUGFS_VOUT_MIN:
 125                 ret = VOLT_FROM_REG(data->mfr_voutmin * 10000);
 126                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d.%d\n",
 127                                 ret / 10000, ret % 10000);
 128                 break;
 129         case MAX20730_DEBUGFS_FREQUENCY:
 130                 val = (data->mfr_devset1 & MAX20730_MFR_DEVSET1_FSW_MASK)
 131                         >> MAX20730_MFR_DEVSET1_FSW_BIT_POS;
 132
 133                 if (val == 0)
 134                         ret = 400;
 135                 else if (val == 1)
 136                         ret = 500;
 137                 else if (val == 2 || val == 3)
 138                         ret = 600;
 139                 else if (val == 4)
 140                         ret = 700;
 141                 else if (val == 5)
 142                         ret = 800;
 143                 else
 144                         ret = 900;
 145                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
 146                 break;
 147         case MAX20730_DEBUGFS_PG_DELAY:
 148                 val = (data->mfr_devset1 & MAX20730_MFR_DEVSET1_TSTAT_MASK)
 149                         >> MAX20730_MFR_DEVSET1_TSTAT_BIT_POS;
 150
 151                 if (val == 0)
 152                         result = "2000\n";
 153                 else if (val == 1)
 154                         result = "125\n";
 155                 else if (val == 2)
 156                         result = "62.5\n";
 157                 else
 158                         result = "32\n";
 159                 break;
 160         case MAX20730_DEBUGFS_INTERNAL_GAIN:
 161                 val = (data->mfr_devset1 & MAX20730_MFR_DEVSET1_RGAIN_MASK)
 162                         >> MAX20730_MFR_DEVSET1_RGAIN_BIT_POS;
 163
 164                 if (data->id == max20734) {
 165                         /* AN6209 */
 166                         if (val == 0)
 167                                 result = "0.8\n";
 168                         else if (val == 1)
 169                                 result = "3.2\n";
 170                         else if (val == 2)
 171                                 result = "1.6\n";
 172                         else
 173                                 result = "6.4\n";
 174                 } else if (data->id == max20730 || data->id == max20710) {
 175                         /* AN6042 or AN6140 */
 176                         if (val == 0)
 177                                 result = "0.9\n";
 178                         else if (val == 1)
 179                                 result = "3.6\n";
 180                         else if (val == 2)
 181                                 result = "1.8\n";
 182                         else
 183                                 result = "7.2\n";
 184                 } else if (data->id == max20743) {
 185                         /* AN6042 */
 186                         if (val == 0)
 187                                 result = "0.45\n";
 188                         else if (val == 1)
 189                                 result = "1.8\n";
 190                         else if (val == 2)
 191                                 result = "0.9\n";
 192                         else
 193                                 result = "3.6\n";
 194                 } else {
 195                         result = "Not supported\n";
 196                 }
 197                 break;
 198         case MAX20730_DEBUGFS_BOOT_VOLTAGE:
 199                 val = (data->mfr_devset1 & MAX20730_MFR_DEVSET1_VBOOT_MASK)
 200                         >> MAX20730_MFR_DEVSET1_VBOOT_BIT_POS;
 201
 202                 if (val == 0)
 203                         result = "0.6484\n";
 204                 else if (val == 1)
 205                         result = "0.8984\n";
 206                 else if (val == 2)
 207                         result = "1.0\n";
 208                 else
 209                         result = "Invalid\n";
 210                 break;
 211         case MAX20730_DEBUGFS_OUT_V_RAMP_RATE:
 212                 val = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_VRATE)
 213                         >> MAX20730_MFR_DEVSET2_VRATE_BIT_POS;
 214
 215                 if (val == 0)
 216                         result = "4\n";
 217                 else if (val == 1)
 218                         result = "2\n";
 219                 else if (val == 2)
 220                         result = "1\n";
 221                 else
 222                         result = "Invalid\n";
 223                 break;
 224         case MAX20730_DEBUGFS_OC_PROTECT_MODE:
 225                 ret = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_OCPM_MASK)
 226                         >> MAX20730_MFR_DEVSET2_OCPM_BIT_POS;
 227                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
 228                 break;
 229         case MAX20730_DEBUGFS_SS_TIMING:
 230                 val = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_SS_MASK)
 231                         >> MAX20730_MFR_DEVSET2_SS_BIT_POS;
 232
 233                 if (val == 0)
 234                         result = "0.75\n";
 235                 else if (val == 1)
 236                         result = "1.5\n";
 237                 else if (val == 2)
 238                         result = "3\n";
 239                 else
 240                         result = "6\n";
 241                 break;
 242         case MAX20730_DEBUGFS_IMAX:
 243                 ret = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_IMAX_MASK)
 244                         >> MAX20730_MFR_DEVSET2_IMAX_BIT_POS;
 245                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
 246                 break;
 247         case MAX20730_DEBUGFS_OPERATION:
 248                 ret = i2c_smbus_read_byte_data(psu->client, PMBUS_OPERATION);
 249                 if (ret < 0)
 250                         return ret;
 251                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
 252                 break;
 253         case MAX20730_DEBUGFS_ON_OFF_CONFIG:
 254                 ret = i2c_smbus_read_byte_data(psu->client, PMBUS_ON_OFF_CONFIG);
 255                 if (ret < 0)
 256                         return ret;
 257                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
 258                 break;
 259         case MAX20730_DEBUGFS_SMBALERT_MASK:
 260                 ret = i2c_smbus_read_word_data(psu->client,
 261                                                PMBUS_SMB_ALERT_MASK);
 262                 if (ret < 0)
 263                         return ret;
 264                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
 265                 break;
 266         case MAX20730_DEBUGFS_VOUT_MODE:
 267                 ret = i2c_smbus_read_byte_data(psu->client, PMBUS_VOUT_MODE);
 268                 if (ret < 0)
 269                         return ret;
 270                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
 271                 break;
 272         case MAX20730_DEBUGFS_VOUT_COMMAND:
 273                 ret = i2c_smbus_read_word_data(psu->client, PMBUS_VOUT_COMMAND);
 274                 if (ret < 0)
 275                         return ret;
 276
 277                 ret = VOLT_FROM_REG(ret * 10000);
 278                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX,
 279                                 "%d.%d\n", ret / 10000, ret % 10000);
 280                 break;
 281         case MAX20730_DEBUGFS_VOUT_MAX:
 282                 ret = i2c_smbus_read_word_data(psu->client, PMBUS_VOUT_MAX);
 283                 if (ret < 0)
 284                         return ret;
 285
 286                 ret = VOLT_FROM_REG(ret * 10000);
 287                 len = scnprintf(tbuf, DEBUG_FS_DATA_MAX,
 288                                 "%d.%d\n", ret / 10000, ret % 10000);
 289                 break;
 290         default:
 291                 result = "Invalid\n";
 292         }
 293
 294         len = strlen(result);
 295         return simple_read_from_buffer(buf, count, ppos, result, len);
 296 }
 297
 298 static const struct file_operations max20730_fops = {
 299         .llseek = noop_llseek,
 300         .read = max20730_debugfs_read,
 301         .write = NULL,
 302         .open = simple_open,
 303 };
 304
 305 static int max20730_init_debugfs(struct i2c_client *client,
 306                                  struct max20730_data *data)
 307 {
 308         int ret, i;
 309         struct dentry *debugfs;
 310         struct dentry *max20730_dir;
 311         struct max20730_debugfs_data *psu;
 312
 313         ret = i2c_smbus_read_word_data(client, MAX20730_MFR_DEVSET2);
 314         if (ret < 0)
 315                 return ret;
 316         data->mfr_devset2 = ret;
 317
 318         ret = i2c_smbus_read_word_data(client, MAX20730_MFR_VOUT_MIN);
 319         if (ret < 0)
 320                 return ret;
 321         data->mfr_voutmin = ret;
 322
 323         psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
 324         if (!psu)
 325                 return -ENOMEM;
 326         psu->client = client;
 327
 328         debugfs = pmbus_get_debugfs_dir(client);
 329         if (!debugfs)
 330                 return -ENOENT;
 331
 332         max20730_dir = debugfs_create_dir(client->name, debugfs);
 333
 334         for (i = 0; i < MAX20730_DEBUGFS_NUM_ENTRIES; ++i)
 335                 psu->debugfs_entries[i] = i;
 336
 337         debugfs_create_file("vout_min", 0444, max20730_dir,
 338                             &psu->debugfs_entries[MAX20730_DEBUGFS_VOUT_MIN],
 339                             &max20730_fops);
 340         debugfs_create_file("frequency", 0444, max20730_dir,
 341                             &psu->debugfs_entries[MAX20730_DEBUGFS_FREQUENCY],
 342                             &max20730_fops);
 343         debugfs_create_file("power_good_delay", 0444, max20730_dir,
 344                             &psu->debugfs_entries[MAX20730_DEBUGFS_PG_DELAY],
 345                             &max20730_fops);
 346         debugfs_create_file("internal_gain", 0444, max20730_dir,
 347                             &psu->debugfs_entries[MAX20730_DEBUGFS_INTERNAL_GAIN],
 348                             &max20730_fops);
 349         debugfs_create_file("boot_voltage", 0444, max20730_dir,
 350                             &psu->debugfs_entries[MAX20730_DEBUGFS_BOOT_VOLTAGE],
 351                             &max20730_fops);
 352         debugfs_create_file("out_voltage_ramp_rate", 0444, max20730_dir,
 353                             &psu->debugfs_entries[MAX20730_DEBUGFS_OUT_V_RAMP_RATE],
 354                             &max20730_fops);
 355         debugfs_create_file("oc_protection_mode", 0444, max20730_dir,
 356                             &psu->debugfs_entries[MAX20730_DEBUGFS_OC_PROTECT_MODE],
 357                             &max20730_fops);
 358         debugfs_create_file("soft_start_timing", 0444, max20730_dir,
 359                             &psu->debugfs_entries[MAX20730_DEBUGFS_SS_TIMING],
 360                             &max20730_fops);
 361         debugfs_create_file("imax", 0444, max20730_dir,
 362                             &psu->debugfs_entries[MAX20730_DEBUGFS_IMAX],
 363                             &max20730_fops);
 364         debugfs_create_file("operation", 0444, max20730_dir,
 365                             &psu->debugfs_entries[MAX20730_DEBUGFS_OPERATION],
 366                             &max20730_fops);
 367         debugfs_create_file("on_off_config", 0444, max20730_dir,
 368                             &psu->debugfs_entries[MAX20730_DEBUGFS_ON_OFF_CONFIG],
 369                             &max20730_fops);
 370         debugfs_create_file("smbalert_mask", 0444, max20730_dir,
 371                             &psu->debugfs_entries[MAX20730_DEBUGFS_SMBALERT_MASK],
 372                             &max20730_fops);
 373         debugfs_create_file("vout_mode", 0444, max20730_dir,
 374                             &psu->debugfs_entries[MAX20730_DEBUGFS_VOUT_MODE],
 375                             &max20730_fops);
 376         debugfs_create_file("vout_command", 0444, max20730_dir,
 377                             &psu->debugfs_entries[MAX20730_DEBUGFS_VOUT_COMMAND],
 378                             &max20730_fops);
 379         debugfs_create_file("vout_max", 0444, max20730_dir,
 380                             &psu->debugfs_entries[MAX20730_DEBUGFS_VOUT_MAX],
 381                             &max20730_fops);
 382
 383         return 0;
 384 }
 385 #else
 386 static int max20730_init_debugfs(struct i2c_client *client,
 387                                  struct max20730_data *data)
 388 {
 389         return 0;
 390 }
 391 #endif /* CONFIG_DEBUG_FS */
 392
 393 static const struct i2c_device_id max20730_id[];
 394
 395 /*
 396  * Convert discreet value to direct data format. Strictly speaking, all passed
 397  * values are constants, so we could do that calculation manually. On the
 398  * downside, that would make the driver more difficult to maintain, so lets
 399  * use this approach.
 400  */
 401 static u16 val_to_direct(int v, enum pmbus_sensor_classes class,
 402                          const struct pmbus_driver_info *info)
 403 {
 404         int R = info->R[class] - 3;     /* take milli-units into account */
 405         int b = info->b[class] * 1000;
 406         long d;
 407
 408         d = v * info->m[class] + b;
 409         /*
 410          * R < 0 is true for all callers, so we don't need to bother
 411          * about the R > 0 case.
 412          */
 413         while (R < 0) {
 414                 d = DIV_ROUND_CLOSEST(d, 10);
 415                 R++;
 416         }
 417         return (u16)d;
 418 }
 419
 420 static long direct_to_val(u16 w, enum pmbus_sensor_classes class,
 421                           const struct pmbus_driver_info *info)
 422 {
 423         int R = info->R[class] - 3;
 424         int b = info->b[class] * 1000;
 425         int m = info->m[class];
 426         long d = (s16)w;
 427
 428         if (m == 0)
 429                 return 0;
 430
 431         while (R < 0) {
 432                 d *= 10;
 433                 R++;
 434         }
 435         d = (d - b) / m;
 436         return d;
 437 }
 438
 439 static u32 max_current[][5] = {
 440         [max20710] = { 6200, 8000, 9700, 11600 },
 441         [max20730] = { 13000, 16600, 20100, 23600 },
 442         [max20734] = { 21000, 27000, 32000, 38000 },
 443         [max20743] = { 18900, 24100, 29200, 34100 },
 444 };
 445
 446 static int max20730_read_word_data(struct i2c_client *client, int page,
 447                                    int phase, int reg)
 448 {
 449         const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
 450         const struct max20730_data *data = to_max20730_data(info);
 451         int ret = 0;
 452         u32 max_c;
 453
 454         switch (reg) {
 455         case PMBUS_OT_FAULT_LIMIT:
 456                 switch ((data->mfr_devset1 >> 11) & 0x3) {
 457                 case 0x0:
 458                         ret = val_to_direct(150000, PSC_TEMPERATURE, info);
 459                         break;
 460                 case 0x1:
 461                         ret = val_to_direct(130000, PSC_TEMPERATURE, info);
 462                         break;
 463                 default:
 464                         ret = -ENODATA;
 465                         break;
 466                 }
 467                 break;
 468         case PMBUS_IOUT_OC_FAULT_LIMIT:
 469                 max_c = max_current[data->id][(data->mfr_devset1 >> 5) & 0x3];
 470                 ret = val_to_direct(max_c, PSC_CURRENT_OUT, info);
 471                 break;
 472         case PMBUS_READ_VOUT:
 473                 ret = pmbus_read_word_data(client, page, phase, reg);
 474                 if (ret > 0 && data->vout_voltage_divider[0] && data->vout_voltage_divider[1]) {
 475                         u64 temp = DIV_ROUND_CLOSEST_ULL((u64)ret * data->vout_voltage_divider[1],
 476                                                          data->vout_voltage_divider[0]);
 477                         ret = clamp_val(temp, 0, 0xffff);
 478                 }
 479                 break;
 480         default:
 481                 ret = -ENODATA;
 482                 break;
 483         }
 484         return ret;
 485 }
 486
 487 static int max20730_write_word_data(struct i2c_client *client, int page,
 488                                     int reg, u16 word)
 489 {
 490         struct pmbus_driver_info *info;
 491         struct max20730_data *data;
 492         u16 devset1;
 493         int ret = 0;
 494         int idx;
 495
 496         info = (struct pmbus_driver_info *)pmbus_get_driver_info(client);
 497         data = to_max20730_data(info);
 498
 499         mutex_lock(&data->lock);
 500         devset1 = data->mfr_devset1;
 501
 502         switch (reg) {
 503         case PMBUS_OT_FAULT_LIMIT:
 504                 devset1 &= ~(BIT(11) | BIT(12));
 505                 if (direct_to_val(word, PSC_TEMPERATURE, info) < 140000)
 506                         devset1 |= BIT(11);
 507                 break;
 508         case PMBUS_IOUT_OC_FAULT_LIMIT:
 509                 devset1 &= ~(BIT(5) | BIT(6));
 510
 511                 idx = find_closest(direct_to_val(word, PSC_CURRENT_OUT, info),
 512                                    max_current[data->id], 4);
 513                 devset1 |= (idx << 5);
 514                 break;
 515         default:
 516                 ret = -ENODATA;
 517                 break;
 518         }
 519
 520         if (!ret && devset1 != data->mfr_devset1) {
 521                 ret = i2c_smbus_write_word_data(client, MAX20730_MFR_DEVSET1,
 522                                                 devset1);
 523                 if (!ret) {
 524                         data->mfr_devset1 = devset1;
 525                         pmbus_clear_cache(client);
 526                 }
 527         }
 528         mutex_unlock(&data->lock);
 529         return ret;
 530 }
 531
 532 static const struct pmbus_driver_info max20730_info[] = {
 533         [max20710] = {
 534                 .pages = 1,
 535                 .read_word_data = max20730_read_word_data,
 536                 .write_word_data = max20730_write_word_data,
 537
 538                 /* Source : Maxim AN6140 and AN6042 */
 539                 .format[PSC_TEMPERATURE] = direct,
 540                 .m[PSC_TEMPERATURE] = 21,
 541                 .b[PSC_TEMPERATURE] = 5887,
 542                 .R[PSC_TEMPERATURE] = -1,
 543
 544                 .format[PSC_VOLTAGE_IN] = direct,
 545                 .m[PSC_VOLTAGE_IN] = 3609,
 546                 .b[PSC_VOLTAGE_IN] = 0,
 547                 .R[PSC_VOLTAGE_IN] = -2,
 548
 549                 .format[PSC_CURRENT_OUT] = direct,
 550                 .m[PSC_CURRENT_OUT] = 153,
 551                 .b[PSC_CURRENT_OUT] = 4976,
 552                 .R[PSC_CURRENT_OUT] = -1,
 553
 554                 .format[PSC_VOLTAGE_OUT] = linear,
 555
 556                 .func[0] = PMBUS_HAVE_VIN |
 557                         PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
 558                         PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
 559                         PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
 560                         PMBUS_HAVE_STATUS_INPUT,
 561         },
 562         [max20730] = {
 563                 .pages = 1,
 564                 .read_word_data = max20730_read_word_data,
 565                 .write_word_data = max20730_write_word_data,
 566
 567                 /* Source : Maxim AN6042 */
 568                 .format[PSC_TEMPERATURE] = direct,
 569                 .m[PSC_TEMPERATURE] = 21,
 570                 .b[PSC_TEMPERATURE] = 5887,
 571                 .R[PSC_TEMPERATURE] = -1,
 572
 573                 .format[PSC_VOLTAGE_IN] = direct,
 574                 .m[PSC_VOLTAGE_IN] = 3609,
 575                 .b[PSC_VOLTAGE_IN] = 0,
 576                 .R[PSC_VOLTAGE_IN] = -2,
 577
 578                 /*
 579                  * Values in the datasheet are adjusted for temperature and
 580                  * for the relationship between Vin and Vout.
 581                  * Unfortunately, the data sheet suggests that Vout measurement
 582                  * may be scaled with a resistor array. This is indeed the case
 583                  * at least on the evaulation boards. As a result, any in-driver
 584                  * adjustments would either be wrong or require elaborate means
 585                  * to configure the scaling. Instead of doing that, just report
 586                  * raw values and let userspace handle adjustments.
 587                  */
 588                 .format[PSC_CURRENT_OUT] = direct,
 589                 .m[PSC_CURRENT_OUT] = 153,
 590                 .b[PSC_CURRENT_OUT] = 4976,
 591                 .R[PSC_CURRENT_OUT] = -1,
 592
 593                 .format[PSC_VOLTAGE_OUT] = linear,
 594
 595                 .func[0] = PMBUS_HAVE_VIN |
 596                         PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
 597                         PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
 598                         PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
 599                         PMBUS_HAVE_STATUS_INPUT,
 600         },
 601         [max20734] = {
 602                 .pages = 1,
 603                 .read_word_data = max20730_read_word_data,
 604                 .write_word_data = max20730_write_word_data,
 605
 606                 /* Source : Maxim AN6209 */
 607                 .format[PSC_TEMPERATURE] = direct,
 608                 .m[PSC_TEMPERATURE] = 21,
 609                 .b[PSC_TEMPERATURE] = 5887,
 610                 .R[PSC_TEMPERATURE] = -1,
 611
 612                 .format[PSC_VOLTAGE_IN] = direct,
 613                 .m[PSC_VOLTAGE_IN] = 3592,
 614                 .b[PSC_VOLTAGE_IN] = 0,
 615                 .R[PSC_VOLTAGE_IN] = -2,
 616
 617                 .format[PSC_CURRENT_OUT] = direct,
 618                 .m[PSC_CURRENT_OUT] = 111,
 619                 .b[PSC_CURRENT_OUT] = 3461,
 620                 .R[PSC_CURRENT_OUT] = -1,
 621
 622                 .format[PSC_VOLTAGE_OUT] = linear,
 623
 624                 .func[0] = PMBUS_HAVE_VIN |
 625                         PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
 626                         PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
 627                         PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
 628                         PMBUS_HAVE_STATUS_INPUT,
 629         },
 630         [max20743] = {
 631                 .pages = 1,
 632                 .read_word_data = max20730_read_word_data,
 633                 .write_word_data = max20730_write_word_data,
 634
 635                 /* Source : Maxim AN6042 */
 636                 .format[PSC_TEMPERATURE] = direct,
 637                 .m[PSC_TEMPERATURE] = 21,
 638                 .b[PSC_TEMPERATURE] = 5887,
 639                 .R[PSC_TEMPERATURE] = -1,
 640
 641                 .format[PSC_VOLTAGE_IN] = direct,
 642                 .m[PSC_VOLTAGE_IN] = 3597,
 643                 .b[PSC_VOLTAGE_IN] = 0,
 644                 .R[PSC_VOLTAGE_IN] = -2,
 645
 646                 .format[PSC_CURRENT_OUT] = direct,
 647                 .m[PSC_CURRENT_OUT] = 95,
 648                 .b[PSC_CURRENT_OUT] = 5014,
 649                 .R[PSC_CURRENT_OUT] = -1,
 650
 651                 .format[PSC_VOLTAGE_OUT] = linear,
 652
 653                 .func[0] = PMBUS_HAVE_VIN |
 654                         PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
 655                         PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
 656                         PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
 657                         PMBUS_HAVE_STATUS_INPUT,
 658         },
 659 };
 660
 661 static int max20730_probe(struct i2c_client *client)
 662 {
 663         struct device *dev = &client->dev;
 664         u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
 665         struct max20730_data *data;
 666         enum chips chip_id;
 667         int ret;
 668
 669         if (!i2c_check_functionality(client->adapter,
 670                                      I2C_FUNC_SMBUS_READ_BYTE_DATA |
 671                                      I2C_FUNC_SMBUS_READ_WORD_DATA |
 672                                      I2C_FUNC_SMBUS_BLOCK_DATA))
 673                 return -ENODEV;
 674
 675         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
 676         if (ret < 0) {
 677                 dev_err(&client->dev, "Failed to read Manufacturer ID\n");
 678                 return ret;
 679         }
 680         if (ret != 5 || strncmp(buf, "MAXIM", 5)) {
 681                 buf[ret] = '\0';
 682                 dev_err(dev, "Unsupported Manufacturer ID '%s'\n", buf);
 683                 return -ENODEV;
 684         }
 685
 686         /*
 687          * The chips support reading PMBUS_MFR_MODEL. On both MAX20730
 688          * and MAX20734, reading it returns M20743. Presumably that is
 689          * the reason why the command is not documented. Unfortunately,
 690          * that means that there is no reliable means to detect the chip.
 691          * However, we can at least detect the chip series. Compare
 692          * the returned value against 'M20743' and bail out if there is
 693          * a mismatch. If that doesn't work for all chips, we may have
 694          * to remove this check.
 695          */
 696         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
 697         if (ret < 0) {
 698                 dev_err(dev, "Failed to read Manufacturer Model\n");
 699                 return ret;
 700         }
 701         if (ret != 6 || strncmp(buf, "M20743", 6)) {
 702                 buf[ret] = '\0';
 703                 dev_err(dev, "Unsupported Manufacturer Model '%s'\n", buf);
 704                 return -ENODEV;
 705         }
 706
 707         ret = i2c_smbus_read_block_data(client, PMBUS_MFR_REVISION, buf);
 708         if (ret < 0) {
 709                 dev_err(dev, "Failed to read Manufacturer Revision\n");
 710                 return ret;
 711         }
 712         if (ret != 1 || buf[0] != 'F') {
 713                 buf[ret] = '\0';
 714                 dev_err(dev, "Unsupported Manufacturer Revision '%s'\n", buf);
 715                 return -ENODEV;
 716         }
 717
 718         if (client->dev.of_node)
 719                 chip_id = (uintptr_t)of_device_get_match_data(dev);
 720         else
 721                 chip_id = i2c_match_id(max20730_id, client)->driver_data;
 722
 723         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 724         if (!data)
 725                 return -ENOMEM;
 726         data->id = chip_id;
 727         mutex_init(&data->lock);
 728         memcpy(&data->info, &max20730_info[chip_id], sizeof(data->info));
 729         if (of_property_read_u32_array(client->dev.of_node, "vout-voltage-divider",
 730                                        data->vout_voltage_divider,
 731                                        ARRAY_SIZE(data->vout_voltage_divider)) != 0)
 732                 memset(data->vout_voltage_divider, 0, sizeof(data->vout_voltage_divider));
 733         if (data->vout_voltage_divider[1] < data->vout_voltage_divider[0]) {
 734                 dev_err(dev,
 735                         "The total resistance of voltage divider is less than output resistance\n");
 736                 return -EINVAL;
 737         }
 738
 739         ret = i2c_smbus_read_word_data(client, MAX20730_MFR_DEVSET1);
 740         if (ret < 0)
 741                 return ret;
 742         data->mfr_devset1 = ret;
 743
 744         ret = pmbus_do_probe(client, &data->info);
 745         if (ret < 0)
 746                 return ret;
 747
 748         ret = max20730_init_debugfs(client, data);
 749         if (ret)
 750                 dev_warn(dev, "Failed to register debugfs: %d\n",
 751                          ret);
 752
 753         return 0;
 754 }
 755
 756 static const struct i2c_device_id max20730_id[] = {
 757         { "max20710", max20710 },
 758         { "max20730", max20730 },
 759         { "max20734", max20734 },
 760         { "max20743", max20743 },
 761         { },
 762 };
 763
 764 MODULE_DEVICE_TABLE(i2c, max20730_id);
 765
 766 static const struct of_device_id max20730_of_match[] = {
 767         { .compatible = "maxim,max20710", .data = (void *)max20710 },
 768         { .compatible = "maxim,max20730", .data = (void *)max20730 },
 769         { .compatible = "maxim,max20734", .data = (void *)max20734 },
 770         { .compatible = "maxim,max20743", .data = (void *)max20743 },
 771         { },
 772 };
 773
 774 MODULE_DEVICE_TABLE(of, max20730_of_match);
 775
 776 static struct i2c_driver max20730_driver = {
 777         .driver = {
 778                 .name = "max20730",
 779                 .of_match_table = max20730_of_match,
 780         },
 781         .probe = max20730_probe,
 782         .id_table = max20730_id,
 783 };
 784
 785 module_i2c_driver(max20730_driver);
 786
 787 MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
 788 MODULE_DESCRIPTION("PMBus driver for Maxim MAX20710 / MAX20730 / MAX20734 / MAX20743");
 789 MODULE_LICENSE("GPL");
 790 MODULE_IMPORT_NS("PMBUS");