drivers/hwmon/nct7904.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * nct7904.c - driver for Nuvoton NCT7904D.
   4  *
   5  * Copyright (c) 2015 Kontron
   6  * Author: Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/device.h>
  11 #include <linux/init.h>
  12 #include <linux/i2c.h>
  13 #include <linux/mutex.h>
  14 #include <linux/hwmon.h>
  15
  16 #define VENDOR_ID_REG           0x7A    /* Any bank */
  17 #define NUVOTON_ID              0x50
  18 #define CHIP_ID_REG             0x7B    /* Any bank */
  19 #define NCT7904_ID              0xC5
  20 #define DEVICE_ID_REG           0x7C    /* Any bank */
  21
  22 #define BANK_SEL_REG            0xFF
  23 #define BANK_0                  0x00
  24 #define BANK_1                  0x01
  25 #define BANK_2                  0x02
  26 #define BANK_3                  0x03
  27 #define BANK_4                  0x04
  28 #define BANK_MAX                0x04
  29
  30 #define FANIN_MAX               12      /* Counted from 1 */
  31 #define VSEN_MAX                21      /* VSEN1..14, 3VDD, VBAT, V3VSB,
  32                                            LTD (not a voltage), VSEN17..19 */
  33 #define FANCTL_MAX              4       /* Counted from 1 */
  34 #define TCPU_MAX                8       /* Counted from 1 */
  35 #define TEMP_MAX                4       /* Counted from 1 */
  36
  37 #define VT_ADC_CTRL0_REG        0x20    /* Bank 0 */
  38 #define VT_ADC_CTRL1_REG        0x21    /* Bank 0 */
  39 #define VT_ADC_CTRL2_REG        0x22    /* Bank 0 */
  40 #define FANIN_CTRL0_REG         0x24
  41 #define FANIN_CTRL1_REG         0x25
  42 #define DTS_T_CTRL0_REG         0x26
  43 #define DTS_T_CTRL1_REG         0x27
  44 #define VT_ADC_MD_REG           0x2E
  45
  46 #define VSEN1_HV_REG            0x40    /* Bank 0; 2 regs (HV/LV) per sensor */
  47 #define TEMP_CH1_HV_REG         0x42    /* Bank 0; same as VSEN2_HV */
  48 #define LTD_HV_REG              0x62    /* Bank 0; 2 regs in VSEN range */
  49 #define FANIN1_HV_REG           0x80    /* Bank 0; 2 regs (HV/LV) per sensor */
  50 #define T_CPU1_HV_REG           0xA0    /* Bank 0; 2 regs (HV/LV) per sensor */
  51
  52 #define PRTS_REG                0x03    /* Bank 2 */
  53 #define FANCTL1_FMR_REG         0x00    /* Bank 3; 1 reg per channel */
  54 #define FANCTL1_OUT_REG         0x10    /* Bank 3; 1 reg per channel */
  55
  56 static const unsigned short normal_i2c[] = {
  57         0x2d, 0x2e, I2C_CLIENT_END
  58 };
  59
  60 struct nct7904_data {
  61         struct i2c_client *client;
  62         struct mutex bank_lock;
  63         int bank_sel;
  64         u32 fanin_mask;
  65         u32 vsen_mask;
  66         u32 tcpu_mask;
  67         u8 fan_mode[FANCTL_MAX];
  68 };
  69
  70 /* Access functions */
  71 static int nct7904_bank_lock(struct nct7904_data *data, unsigned int bank)
  72 {
  73         int ret;
  74
  75         mutex_lock(&data->bank_lock);
  76         if (data->bank_sel == bank)
  77                 return 0;
  78         ret = i2c_smbus_write_byte_data(data->client, BANK_SEL_REG, bank);
  79         if (ret == 0)
  80                 data->bank_sel = bank;
  81         else
  82                 data->bank_sel = -1;
  83         return ret;
  84 }
  85
  86 static inline void nct7904_bank_release(struct nct7904_data *data)
  87 {
  88         mutex_unlock(&data->bank_lock);
  89 }
  90
  91 /* Read 1-byte register. Returns unsigned reg or -ERRNO on error. */
  92 static int nct7904_read_reg(struct nct7904_data *data,
  93                             unsigned int bank, unsigned int reg)
  94 {
  95         struct i2c_client *client = data->client;
  96         int ret;
  97
  98         ret = nct7904_bank_lock(data, bank);
  99         if (ret == 0)
 100                 ret = i2c_smbus_read_byte_data(client, reg);
 101
 102         nct7904_bank_release(data);
 103         return ret;
 104 }
 105
 106 /*
 107  * Read 2-byte register. Returns register in big-endian format or
 108  * -ERRNO on error.
 109  */
 110 static int nct7904_read_reg16(struct nct7904_data *data,
 111                               unsigned int bank, unsigned int reg)
 112 {
 113         struct i2c_client *client = data->client;
 114         int ret, hi;
 115
 116         ret = nct7904_bank_lock(data, bank);
 117         if (ret == 0) {
 118                 ret = i2c_smbus_read_byte_data(client, reg);
 119                 if (ret >= 0) {
 120                         hi = ret;
 121                         ret = i2c_smbus_read_byte_data(client, reg + 1);
 122                         if (ret >= 0)
 123                                 ret |= hi << 8;
 124                 }
 125         }
 126
 127         nct7904_bank_release(data);
 128         return ret;
 129 }
 130
 131 /* Write 1-byte register. Returns 0 or -ERRNO on error. */
 132 static int nct7904_write_reg(struct nct7904_data *data,
 133                              unsigned int bank, unsigned int reg, u8 val)
 134 {
 135         struct i2c_client *client = data->client;
 136         int ret;
 137
 138         ret = nct7904_bank_lock(data, bank);
 139         if (ret == 0)
 140                 ret = i2c_smbus_write_byte_data(client, reg, val);
 141
 142         nct7904_bank_release(data);
 143         return ret;
 144 }
 145
 146 static int nct7904_read_fan(struct device *dev, u32 attr, int channel,
 147                             long *val)
 148 {
 149         struct nct7904_data *data = dev_get_drvdata(dev);
 150         unsigned int cnt, rpm;
 151         int ret;
 152
 153         switch (attr) {
 154         case hwmon_fan_input:
 155                 ret = nct7904_read_reg16(data, BANK_0,
 156                                          FANIN1_HV_REG + channel * 2);
 157                 if (ret < 0)
 158                         return ret;
 159                 cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
 160                 if (cnt == 0x1fff)
 161                         rpm = 0;
 162                 else
 163                         rpm = 1350000 / cnt;
 164                 *val = rpm;
 165                 return 0;
 166         default:
 167                 return -EOPNOTSUPP;
 168         }
 169 }
 170
 171 static umode_t nct7904_fan_is_visible(const void *_data, u32 attr, int channel)
 172 {
 173         const struct nct7904_data *data = _data;
 174
 175         if (attr == hwmon_fan_input && data->fanin_mask & (1 << channel))
 176                 return 0444;
 177         return 0;
 178 }
 179
 180 static u8 nct7904_chan_to_index[] = {
 181         0,      /* Not used */
 182         0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
 183         18, 19, 20, 16
 184 };
 185
 186 static int nct7904_read_in(struct device *dev, u32 attr, int channel,
 187                            long *val)
 188 {
 189         struct nct7904_data *data = dev_get_drvdata(dev);
 190         int ret, volt, index;
 191
 192         index = nct7904_chan_to_index[channel];
 193
 194         switch (attr) {
 195         case hwmon_in_input:
 196                 ret = nct7904_read_reg16(data, BANK_0,
 197                                          VSEN1_HV_REG + index * 2);
 198                 if (ret < 0)
 199                         return ret;
 200                 volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
 201                 if (index < 14)
 202                         volt *= 2; /* 0.002V scale */
 203                 else
 204                         volt *= 6; /* 0.006V scale */
 205                 *val = volt;
 206                 return 0;
 207         default:
 208                 return -EOPNOTSUPP;
 209         }
 210 }
 211
 212 static umode_t nct7904_in_is_visible(const void *_data, u32 attr, int channel)
 213 {
 214         const struct nct7904_data *data = _data;
 215         int index = nct7904_chan_to_index[channel];
 216
 217         if (channel > 0 && attr == hwmon_in_input &&
 218             (data->vsen_mask & BIT(index)))
 219                 return 0444;
 220
 221         return 0;
 222 }
 223
 224 static int nct7904_read_temp(struct device *dev, u32 attr, int channel,
 225                              long *val)
 226 {
 227         struct nct7904_data *data = dev_get_drvdata(dev);
 228         int ret, temp;
 229
 230         switch (attr) {
 231         case hwmon_temp_input:
 232                 if (channel == 0)
 233                         ret = nct7904_read_reg16(data, BANK_0, LTD_HV_REG);
 234                 else
 235                         ret = nct7904_read_reg16(data, BANK_0,
 236                                         T_CPU1_HV_REG + (channel - 1) * 2);
 237                 if (ret < 0)
 238                         return ret;
 239                 temp = ((ret & 0xff00) >> 5) | (ret & 0x7);
 240                 *val = sign_extend32(temp, 10) * 125;
 241                 return 0;
 242         default:
 243                 return -EOPNOTSUPP;
 244         }
 245 }
 246
 247 static umode_t nct7904_temp_is_visible(const void *_data, u32 attr, int channel)
 248 {
 249         const struct nct7904_data *data = _data;
 250
 251         if (attr == hwmon_temp_input) {
 252                 if (channel == 0) {
 253                         if (data->vsen_mask & BIT(17))
 254                                 return 0444;
 255                 } else {
 256                         if (data->tcpu_mask & BIT(channel - 1))
 257                                 return 0444;
 258                 }
 259         }
 260
 261         return 0;
 262 }
 263
 264 static int nct7904_read_pwm(struct device *dev, u32 attr, int channel,
 265                             long *val)
 266 {
 267         struct nct7904_data *data = dev_get_drvdata(dev);
 268         int ret;
 269
 270         switch (attr) {
 271         case hwmon_pwm_input:
 272                 ret = nct7904_read_reg(data, BANK_3, FANCTL1_OUT_REG + channel);
 273                 if (ret < 0)
 274                         return ret;
 275                 *val = ret;
 276                 return 0;
 277         case hwmon_pwm_enable:
 278                 ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + channel);
 279                 if (ret < 0)
 280                         return ret;
 281
 282                 *val = ret ? 2 : 1;
 283                 return 0;
 284         default:
 285                 return -EOPNOTSUPP;
 286         }
 287 }
 288
 289 static int nct7904_write_pwm(struct device *dev, u32 attr, int channel,
 290                              long val)
 291 {
 292         struct nct7904_data *data = dev_get_drvdata(dev);
 293         int ret;
 294
 295         switch (attr) {
 296         case hwmon_pwm_input:
 297                 if (val < 0 || val > 255)
 298                         return -EINVAL;
 299                 ret = nct7904_write_reg(data, BANK_3, FANCTL1_OUT_REG + channel,
 300                                         val);
 301                 return ret;
 302         case hwmon_pwm_enable:
 303                 if (val < 1 || val > 2 ||
 304                     (val == 2 && !data->fan_mode[channel]))
 305                         return -EINVAL;
 306                 ret = nct7904_write_reg(data, BANK_3, FANCTL1_FMR_REG + channel,
 307                                         val == 2 ? data->fan_mode[channel] : 0);
 308                 return ret;
 309         default:
 310                 return -EOPNOTSUPP;
 311         }
 312 }
 313
 314 static umode_t nct7904_pwm_is_visible(const void *_data, u32 attr, int channel)
 315 {
 316         switch (attr) {
 317         case hwmon_pwm_input:
 318         case hwmon_pwm_enable:
 319                 return 0644;
 320         default:
 321                 return 0;
 322         }
 323 }
 324
 325 static int nct7904_read(struct device *dev, enum hwmon_sensor_types type,
 326                         u32 attr, int channel, long *val)
 327 {
 328         switch (type) {
 329         case hwmon_in:
 330                 return nct7904_read_in(dev, attr, channel, val);
 331         case hwmon_fan:
 332                 return nct7904_read_fan(dev, attr, channel, val);
 333         case hwmon_pwm:
 334                 return nct7904_read_pwm(dev, attr, channel, val);
 335         case hwmon_temp:
 336                 return nct7904_read_temp(dev, attr, channel, val);
 337         default:
 338                 return -EOPNOTSUPP;
 339         }
 340 }
 341
 342 static int nct7904_write(struct device *dev, enum hwmon_sensor_types type,
 343                          u32 attr, int channel, long val)
 344 {
 345         switch (type) {
 346         case hwmon_pwm:
 347                 return nct7904_write_pwm(dev, attr, channel, val);
 348         default:
 349                 return -EOPNOTSUPP;
 350         }
 351 }
 352
 353 static umode_t nct7904_is_visible(const void *data,
 354                                   enum hwmon_sensor_types type,
 355                                   u32 attr, int channel)
 356 {
 357         switch (type) {
 358         case hwmon_in:
 359                 return nct7904_in_is_visible(data, attr, channel);
 360         case hwmon_fan:
 361                 return nct7904_fan_is_visible(data, attr, channel);
 362         case hwmon_pwm:
 363                 return nct7904_pwm_is_visible(data, attr, channel);
 364         case hwmon_temp:
 365                 return nct7904_temp_is_visible(data, attr, channel);
 366         default:
 367                 return 0;
 368         }
 369 }
 370
 371 /* Return 0 if detection is successful, -ENODEV otherwise */
 372 static int nct7904_detect(struct i2c_client *client,
 373                           struct i2c_board_info *info)
 374 {
 375         struct i2c_adapter *adapter = client->adapter;
 376
 377         if (!i2c_check_functionality(adapter,
 378                                      I2C_FUNC_SMBUS_READ_BYTE |
 379                                      I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
 380                 return -ENODEV;
 381
 382         /* Determine the chip type. */
 383         if (i2c_smbus_read_byte_data(client, VENDOR_ID_REG) != NUVOTON_ID ||
 384             i2c_smbus_read_byte_data(client, CHIP_ID_REG) != NCT7904_ID ||
 385             (i2c_smbus_read_byte_data(client, DEVICE_ID_REG) & 0xf0) != 0x50 ||
 386             (i2c_smbus_read_byte_data(client, BANK_SEL_REG) & 0xf8) != 0x00)
 387                 return -ENODEV;
 388
 389         strlcpy(info->type, "nct7904", I2C_NAME_SIZE);
 390
 391         return 0;
 392 }
 393
 394 static const struct hwmon_channel_info *nct7904_info[] = {
 395         HWMON_CHANNEL_INFO(in,
 396                            HWMON_I_INPUT, /* dummy, skipped in is_visible */
 397                            HWMON_I_INPUT,
 398                            HWMON_I_INPUT,
 399                            HWMON_I_INPUT,
 400                            HWMON_I_INPUT,
 401                            HWMON_I_INPUT,
 402                            HWMON_I_INPUT,
 403                            HWMON_I_INPUT,
 404                            HWMON_I_INPUT,
 405                            HWMON_I_INPUT,
 406                            HWMON_I_INPUT,
 407                            HWMON_I_INPUT,
 408                            HWMON_I_INPUT,
 409                            HWMON_I_INPUT,
 410                            HWMON_I_INPUT,
 411                            HWMON_I_INPUT,
 412                            HWMON_I_INPUT,
 413                            HWMON_I_INPUT,
 414                            HWMON_I_INPUT,
 415                            HWMON_I_INPUT,
 416                            HWMON_I_INPUT),
 417         HWMON_CHANNEL_INFO(fan,
 418                            HWMON_F_INPUT,
 419                            HWMON_F_INPUT,
 420                            HWMON_F_INPUT,
 421                            HWMON_F_INPUT,
 422                            HWMON_F_INPUT,
 423                            HWMON_F_INPUT,
 424                            HWMON_F_INPUT,
 425                            HWMON_F_INPUT),
 426         HWMON_CHANNEL_INFO(pwm,
 427                            HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
 428                            HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
 429                            HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
 430                            HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
 431         HWMON_CHANNEL_INFO(temp,
 432                            HWMON_T_INPUT,
 433                            HWMON_T_INPUT,
 434                            HWMON_T_INPUT,
 435                            HWMON_T_INPUT,
 436                            HWMON_T_INPUT,
 437                            HWMON_T_INPUT,
 438                            HWMON_T_INPUT,
 439                            HWMON_T_INPUT,
 440                            HWMON_T_INPUT),
 441         NULL
 442 };
 443
 444 static const struct hwmon_ops nct7904_hwmon_ops = {
 445         .is_visible = nct7904_is_visible,
 446         .read = nct7904_read,
 447         .write = nct7904_write,
 448 };
 449
 450 static const struct hwmon_chip_info nct7904_chip_info = {
 451         .ops = &nct7904_hwmon_ops,
 452         .info = nct7904_info,
 453 };
 454
 455 static int nct7904_probe(struct i2c_client *client,
 456                          const struct i2c_device_id *id)
 457 {
 458         struct nct7904_data *data;
 459         struct device *hwmon_dev;
 460         struct device *dev = &client->dev;
 461         int ret, i;
 462         u32 mask;
 463
 464         data = devm_kzalloc(dev, sizeof(struct nct7904_data), GFP_KERNEL);
 465         if (!data)
 466                 return -ENOMEM;
 467
 468         data->client = client;
 469         mutex_init(&data->bank_lock);
 470         data->bank_sel = -1;
 471
 472         /* Setup sensor groups. */
 473         /* FANIN attributes */
 474         ret = nct7904_read_reg16(data, BANK_0, FANIN_CTRL0_REG);
 475         if (ret < 0)
 476                 return ret;
 477         data->fanin_mask = (ret >> 8) | ((ret & 0xff) << 8);
 478
 479         /*
 480          * VSEN attributes
 481          *
 482          * Note: voltage sensors overlap with external temperature
 483          * sensors. So, if we ever decide to support the latter
 484          * we will have to adjust 'vsen_mask' accordingly.
 485          */
 486         mask = 0;
 487         ret = nct7904_read_reg16(data, BANK_0, VT_ADC_CTRL0_REG);
 488         if (ret >= 0)
 489                 mask = (ret >> 8) | ((ret & 0xff) << 8);
 490         ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
 491         if (ret >= 0)
 492                 mask |= (ret << 16);
 493         data->vsen_mask = mask;
 494
 495         /* CPU_TEMP attributes */
 496         ret = nct7904_read_reg16(data, BANK_0, DTS_T_CTRL0_REG);
 497         if (ret < 0)
 498                 return ret;
 499         data->tcpu_mask = ((ret >> 8) & 0xf) | ((ret & 0xf) << 4);
 500
 501         for (i = 0; i < FANCTL_MAX; i++) {
 502                 ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + i);
 503                 if (ret < 0)
 504                         return ret;
 505                 data->fan_mode[i] = ret;
 506         }
 507
 508         hwmon_dev =
 509                 devm_hwmon_device_register_with_info(dev, client->name, data,
 510                                                      &nct7904_chip_info, NULL);
 511         return PTR_ERR_OR_ZERO(hwmon_dev);
 512 }
 513
 514 static const struct i2c_device_id nct7904_id[] = {
 515         {"nct7904", 0},
 516         {}
 517 };
 518 MODULE_DEVICE_TABLE(i2c, nct7904_id);
 519
 520 static struct i2c_driver nct7904_driver = {
 521         .class = I2C_CLASS_HWMON,
 522         .driver = {
 523                 .name = "nct7904",
 524         },
 525         .probe = nct7904_probe,
 526         .id_table = nct7904_id,
 527         .detect = nct7904_detect,
 528         .address_list = normal_i2c,
 529 };
 530
 531 module_i2c_driver(nct7904_driver);
 532
 533 MODULE_AUTHOR("Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>");
 534 MODULE_DESCRIPTION("Hwmon driver for NUVOTON NCT7904");
 535 MODULE_LICENSE("GPL");