drivers/hwmon/amc6821.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * amc6821.c - Part of lm_sensors, Linux kernel modules for hardware
   4  *             monitoring
   5  * Copyright (C) 2009 T. Mertelj <tomaz.mertelj@guest.arnes.si>
   6  *
   7  * Based on max6650.c:
   8  * Copyright (C) 2007 Hans J. Koch <hjk@hansjkoch.de>
   9  *
  10  * Conversion to regmap and with_info API:
  11  * Copyright (C) 2024 Guenter Roeck <linux@roeck-us.net>
  12  */
  13
  14 #include <linux/bitfield.h>
  15 #include <linux/bitops.h>
  16 #include <linux/bits.h>
  17 #include <linux/err.h>
  18 #include <linux/hwmon.h>
  19 #include <linux/hwmon-sysfs.h>
  20 #include <linux/i2c.h>
  21 #include <linux/init.h>
  22 #include <linux/minmax.h>
  23 #include <linux/module.h>
  24 #include <linux/mutex.h>
  25 #include <linux/of_platform.h>
  26 #include <linux/regmap.h>
  27 #include <linux/slab.h>
  28
  29 /*
  30  * Addresses to scan.
  31  */
  32
  33 static const unsigned short normal_i2c[] = {0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e,
  34         0x4c, 0x4d, 0x4e, I2C_CLIENT_END};
  35
  36 /*
  37  * Insmod parameters
  38  */
  39
  40 static int pwminv;      /*Inverted PWM output. */
  41 module_param(pwminv, int, 0444);
  42
  43 static int init = 1; /*Power-on initialization.*/
  44 module_param(init, int, 0444);
  45
  46 #define AMC6821_REG_DEV_ID              0x3D
  47 #define AMC6821_REG_COMP_ID             0x3E
  48 #define AMC6821_REG_CONF1               0x00
  49 #define AMC6821_REG_CONF2               0x01
  50 #define AMC6821_REG_CONF3               0x3F
  51 #define AMC6821_REG_CONF4               0x04
  52 #define AMC6821_REG_STAT1               0x02
  53 #define AMC6821_REG_STAT2               0x03
  54 #define AMC6821_REG_TEMP_LO             0x06
  55 #define AMC6821_REG_TDATA_LOW           0x08
  56 #define AMC6821_REG_TDATA_HI            0x09
  57 #define AMC6821_REG_LTEMP_HI            0x0A
  58 #define AMC6821_REG_RTEMP_HI            0x0B
  59 #define AMC6821_REG_LTEMP_LIMIT_MIN     0x15
  60 #define AMC6821_REG_LTEMP_LIMIT_MAX     0x14
  61 #define AMC6821_REG_RTEMP_LIMIT_MIN     0x19
  62 #define AMC6821_REG_RTEMP_LIMIT_MAX     0x18
  63 #define AMC6821_REG_LTEMP_CRIT          0x1B
  64 #define AMC6821_REG_RTEMP_CRIT          0x1D
  65 #define AMC6821_REG_PSV_TEMP            0x1C
  66 #define AMC6821_REG_DCY                 0x22
  67 #define AMC6821_REG_LTEMP_FAN_CTRL      0x24
  68 #define AMC6821_REG_RTEMP_FAN_CTRL      0x25
  69 #define AMC6821_REG_DCY_LOW_TEMP        0x21
  70
  71 #define AMC6821_REG_TACH_LLIMITL        0x10
  72 #define AMC6821_REG_TACH_HLIMITL        0x12
  73 #define AMC6821_REG_TACH_SETTINGL       0x1e
  74
  75 #define AMC6821_CONF1_START             BIT(0)
  76 #define AMC6821_CONF1_FAN_INT_EN        BIT(1)
  77 #define AMC6821_CONF1_FANIE             BIT(2)
  78 #define AMC6821_CONF1_PWMINV            BIT(3)
  79 #define AMC6821_CONF1_FAN_FAULT_EN      BIT(4)
  80 #define AMC6821_CONF1_FDRC0             BIT(5)
  81 #define AMC6821_CONF1_FDRC1             BIT(6)
  82 #define AMC6821_CONF1_THERMOVIE         BIT(7)
  83
  84 #define AMC6821_CONF2_PWM_EN            BIT(0)
  85 #define AMC6821_CONF2_TACH_MODE         BIT(1)
  86 #define AMC6821_CONF2_TACH_EN           BIT(2)
  87 #define AMC6821_CONF2_RTFIE             BIT(3)
  88 #define AMC6821_CONF2_LTOIE             BIT(4)
  89 #define AMC6821_CONF2_RTOIE             BIT(5)
  90 #define AMC6821_CONF2_PSVIE             BIT(6)
  91 #define AMC6821_CONF2_RST               BIT(7)
  92
  93 #define AMC6821_CONF3_THERM_FAN_EN      BIT(7)
  94 #define AMC6821_CONF3_REV_MASK          GENMASK(3, 0)
  95
  96 #define AMC6821_CONF4_OVREN             BIT(4)
  97 #define AMC6821_CONF4_TACH_FAST         BIT(5)
  98 #define AMC6821_CONF4_PSPR              BIT(6)
  99 #define AMC6821_CONF4_MODE              BIT(7)
 100
 101 #define AMC6821_STAT1_RPM_ALARM         BIT(0)
 102 #define AMC6821_STAT1_FANS              BIT(1)
 103 #define AMC6821_STAT1_RTH               BIT(2)
 104 #define AMC6821_STAT1_RTL               BIT(3)
 105 #define AMC6821_STAT1_R_THERM           BIT(4)
 106 #define AMC6821_STAT1_RTF               BIT(5)
 107 #define AMC6821_STAT1_LTH               BIT(6)
 108 #define AMC6821_STAT1_LTL               BIT(7)
 109
 110 #define AMC6821_STAT2_RTC               BIT(3)
 111 #define AMC6821_STAT2_LTC               BIT(4)
 112 #define AMC6821_STAT2_LPSV              BIT(5)
 113 #define AMC6821_STAT2_L_THERM           BIT(6)
 114 #define AMC6821_STAT2_THERM_IN          BIT(7)
 115
 116 #define AMC6821_TEMP_SLOPE_MASK         GENMASK(2, 0)
 117 #define AMC6821_TEMP_LIMIT_MASK         GENMASK(7, 3)
 118
 119 /*
 120  * Client data (each client gets its own)
 121  */
 122
 123 struct amc6821_data {
 124         struct regmap *regmap;
 125         struct mutex update_lock;
 126 };
 127
 128 /*
 129  * Return 0 on success or negative error code.
 130  *
 131  * temps returns set of three temperatures, in °C:
 132  * temps[0]: Passive cooling temperature, applies to both channels
 133  * temps[1]: Low temperature, start slope calculations
 134  * temps[2]: High temperature
 135  *
 136  * Channel 0: local, channel 1: remote.
 137  */
 138 static int amc6821_get_auto_point_temps(struct regmap *regmap, int channel, u8 *temps)
 139 {
 140         u32 regs[] = {
 141                 AMC6821_REG_DCY_LOW_TEMP,
 142                 AMC6821_REG_PSV_TEMP,
 143                 channel ? AMC6821_REG_RTEMP_FAN_CTRL : AMC6821_REG_LTEMP_FAN_CTRL
 144         };
 145         u8 regvals[3];
 146         int slope;
 147         int err;
 148
 149         err = regmap_multi_reg_read(regmap, regs, regvals, 3);
 150         if (err)
 151                 return err;
 152         temps[0] = regvals[1];
 153         temps[1] = FIELD_GET(AMC6821_TEMP_LIMIT_MASK, regvals[2]) * 4;
 154
 155         /* slope is 32 >> <slope bits> in °C */
 156         slope = 32 >> FIELD_GET(AMC6821_TEMP_SLOPE_MASK, regvals[2]);
 157         if (slope)
 158                 temps[2] = temps[1] + DIV_ROUND_CLOSEST(255 - regvals[0], slope);
 159         else
 160                 temps[2] = 255;
 161
 162         return 0;
 163 }
 164
 165 static int amc6821_temp_read_values(struct regmap *regmap, u32 attr, int channel, long *val)
 166 {
 167         int reg, err;
 168         u32 regval;
 169
 170         switch (attr) {
 171         case hwmon_temp_input:
 172                 reg = channel ? AMC6821_REG_RTEMP_HI : AMC6821_REG_LTEMP_HI;
 173                 break;
 174         case hwmon_temp_min:
 175                 reg = channel ? AMC6821_REG_RTEMP_LIMIT_MIN : AMC6821_REG_LTEMP_LIMIT_MIN;
 176                 break;
 177         case hwmon_temp_max:
 178                 reg = channel ? AMC6821_REG_RTEMP_LIMIT_MAX : AMC6821_REG_LTEMP_LIMIT_MAX;
 179                 break;
 180         case hwmon_temp_crit:
 181                 reg = channel ? AMC6821_REG_RTEMP_CRIT : AMC6821_REG_LTEMP_CRIT;
 182                 break;
 183         default:
 184                 return -EOPNOTSUPP;
 185         }
 186         err = regmap_read(regmap, reg, &regval);
 187         if (err)
 188                 return err;
 189         *val = sign_extend32(regval, 7) * 1000;
 190         return 0;
 191 }
 192
 193 static int amc6821_read_alarms(struct regmap *regmap, enum hwmon_sensor_types type,
 194                                u32 attr, int channel, long *val)
 195 {
 196         int reg, mask, err;
 197         u32 regval;
 198
 199         switch (type) {
 200         case hwmon_temp:
 201                 switch (attr) {
 202                 case hwmon_temp_min_alarm:
 203                         reg = AMC6821_REG_STAT1;
 204                         mask = channel ? AMC6821_STAT1_RTL : AMC6821_STAT1_LTL;
 205                         break;
 206                 case hwmon_temp_max_alarm:
 207                         reg = AMC6821_REG_STAT1;
 208                         mask = channel ? AMC6821_STAT1_RTH : AMC6821_STAT1_LTH;
 209                         break;
 210                 case hwmon_temp_crit_alarm:
 211                         reg = AMC6821_REG_STAT2;
 212                         mask = channel ? AMC6821_STAT2_RTC : AMC6821_STAT2_LTC;
 213                         break;
 214                 case hwmon_temp_fault:
 215                         reg = AMC6821_REG_STAT1;
 216                         mask = AMC6821_STAT1_RTF;
 217                         break;
 218                 default:
 219                         return -EOPNOTSUPP;
 220                 }
 221                 break;
 222         case hwmon_fan:
 223                 switch (attr) {
 224                 case hwmon_fan_fault:
 225                         reg = AMC6821_REG_STAT1;
 226                         mask = AMC6821_STAT1_FANS;
 227                         break;
 228                 default:
 229                         return -EOPNOTSUPP;
 230                 }
 231                 break;
 232         default:
 233                 return -EOPNOTSUPP;
 234         }
 235         err = regmap_read(regmap, reg, &regval);
 236         if (err)
 237                 return err;
 238         *val = !!(regval & mask);
 239         return 0;
 240 }
 241
 242 static int amc6821_temp_read(struct device *dev, u32 attr, int channel, long *val)
 243 {
 244         struct amc6821_data *data = dev_get_drvdata(dev);
 245
 246         switch (attr) {
 247         case hwmon_temp_input:
 248         case hwmon_temp_min:
 249         case hwmon_temp_max:
 250         case hwmon_temp_crit:
 251                 return amc6821_temp_read_values(data->regmap, attr, channel, val);
 252         case hwmon_temp_min_alarm:
 253         case hwmon_temp_max_alarm:
 254         case hwmon_temp_crit_alarm:
 255         case hwmon_temp_fault:
 256                 return amc6821_read_alarms(data->regmap, hwmon_temp, attr, channel, val);
 257         default:
 258                 return -EOPNOTSUPP;
 259         }
 260 }
 261
 262 static int amc6821_temp_write(struct device *dev, u32 attr, int channel, long val)
 263 {
 264         struct amc6821_data *data = dev_get_drvdata(dev);
 265         int reg;
 266
 267         val = DIV_ROUND_CLOSEST(clamp_val(val, -128000, 127000), 1000);
 268
 269         switch (attr) {
 270         case hwmon_temp_min:
 271                 reg = channel ? AMC6821_REG_RTEMP_LIMIT_MIN : AMC6821_REG_LTEMP_LIMIT_MIN;
 272                 break;
 273         case hwmon_temp_max:
 274                 reg = channel ? AMC6821_REG_RTEMP_LIMIT_MAX : AMC6821_REG_LTEMP_LIMIT_MAX;
 275                 break;
 276         case hwmon_temp_crit:
 277                 reg = channel ? AMC6821_REG_RTEMP_CRIT : AMC6821_REG_LTEMP_CRIT;
 278                 break;
 279         default:
 280                 return -EOPNOTSUPP;
 281         }
 282         return regmap_write(data->regmap, reg, val);
 283 }
 284
 285 static int amc6821_pwm_read(struct device *dev, u32 attr, long *val)
 286 {
 287         struct amc6821_data *data = dev_get_drvdata(dev);
 288         struct regmap *regmap = data->regmap;
 289         u32 regval;
 290         int err;
 291
 292         switch (attr) {
 293         case hwmon_pwm_enable:
 294                 err = regmap_read(regmap, AMC6821_REG_CONF1, &regval);
 295                 if (err)
 296                         return err;
 297                 switch (regval & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
 298                 case 0:
 299                         *val = 1;       /* manual */
 300                         break;
 301                 case AMC6821_CONF1_FDRC0:
 302                         *val = 4;       /* target rpm (fan1_target) controlled */
 303                         break;
 304                 case AMC6821_CONF1_FDRC1:
 305                         *val = 2;       /* remote temp controlled */
 306                         break;
 307                 default:
 308                         *val = 3;       /* max(local, remote) temp controlled */
 309                         break;
 310                 }
 311                 return 0;
 312         case hwmon_pwm_mode:
 313                 err = regmap_read(regmap, AMC6821_REG_CONF2, &regval);
 314                 if (err)
 315                         return err;
 316                 *val = !!(regval & AMC6821_CONF2_TACH_MODE);
 317                 return 0;
 318         case hwmon_pwm_auto_channels_temp:
 319                 err = regmap_read(regmap, AMC6821_REG_CONF1, &regval);
 320                 if (err)
 321                         return err;
 322                 switch (regval & (AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1)) {
 323                 case 0:
 324                 case AMC6821_CONF1_FDRC0:
 325                         *val = 0;       /* manual or target rpm controlled */
 326                         break;
 327                 case AMC6821_CONF1_FDRC1:
 328                         *val = 2;       /* remote temp controlled */
 329                         break;
 330                 default:
 331                         *val = 3;       /* max(local, remote) temp controlled */
 332                         break;
 333                 }
 334                 return 0;
 335         case hwmon_pwm_input:
 336                 err = regmap_read(regmap, AMC6821_REG_DCY, &regval);
 337                 if (err)
 338                         return err;
 339                 *val = regval;
 340                 return 0;
 341         default:
 342                 return -EOPNOTSUPP;
 343         }
 344 }
 345
 346 static int amc6821_pwm_write(struct device *dev, u32 attr, long val)
 347 {
 348         struct amc6821_data *data = dev_get_drvdata(dev);
 349         struct regmap *regmap = data->regmap;
 350         u32 mode;
 351
 352         switch (attr) {
 353         case hwmon_pwm_enable:
 354                 switch (val) {
 355                 case 1:
 356                         mode = 0;
 357                         break;
 358                 case 2:
 359                         mode = AMC6821_CONF1_FDRC1;
 360                         break;
 361                 case 3:
 362                         mode = AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1;
 363                         break;
 364                 case 4:
 365                         mode = AMC6821_CONF1_FDRC0;
 366                         break;
 367                 default:
 368                         return -EINVAL;
 369                 }
 370                 return regmap_update_bits(regmap, AMC6821_REG_CONF1,
 371                                           AMC6821_CONF1_FDRC0 | AMC6821_CONF1_FDRC1,
 372                                           mode);
 373         case hwmon_pwm_mode:
 374                 if (val < 0 || val > 1)
 375                         return -EINVAL;
 376                 return regmap_update_bits(regmap, AMC6821_REG_CONF2,
 377                                           AMC6821_CONF2_TACH_MODE,
 378                                           val ? AMC6821_CONF2_TACH_MODE : 0);
 379                 break;
 380         case hwmon_pwm_input:
 381                 if (val < 0 || val > 255)
 382                         return -EINVAL;
 383                 return regmap_write(regmap, AMC6821_REG_DCY, val);
 384         default:
 385                 return -EOPNOTSUPP;
 386         }
 387 }
 388
 389 static int amc6821_fan_read_rpm(struct regmap *regmap, u32 attr, long *val)
 390 {
 391         int reg, err;
 392         u8 regs[2];
 393         u32 regval;
 394
 395         switch (attr) {
 396         case hwmon_fan_input:
 397                 reg = AMC6821_REG_TDATA_LOW;
 398                 break;
 399         case hwmon_fan_min:
 400                 reg = AMC6821_REG_TACH_LLIMITL;
 401                 break;
 402         case hwmon_fan_max:
 403                 reg = AMC6821_REG_TACH_HLIMITL;
 404                 break;
 405         case hwmon_fan_target:
 406                 reg = AMC6821_REG_TACH_SETTINGL;
 407                 break;
 408         default:
 409                 return -EOPNOTSUPP;
 410         }
 411
 412         err = regmap_bulk_read(regmap, reg, regs, 2);
 413         if (err)
 414                 return err;
 415
 416         regval = (regs[1] << 8) | regs[0];
 417         *val = regval ? 6000000 / regval : 0;
 418
 419         return 0;
 420 }
 421
 422 static int amc6821_fan_read(struct device *dev, u32 attr, long *val)
 423 {
 424         struct amc6821_data *data = dev_get_drvdata(dev);
 425         struct regmap *regmap = data->regmap;
 426         u32 regval;
 427         int err;
 428
 429         switch (attr) {
 430         case hwmon_fan_input:
 431         case hwmon_fan_min:
 432         case hwmon_fan_max:
 433         case hwmon_fan_target:
 434                 return amc6821_fan_read_rpm(regmap, attr, val);
 435         case hwmon_fan_fault:
 436                 return amc6821_read_alarms(regmap, hwmon_fan, attr, 0, val);
 437         case hwmon_fan_pulses:
 438                 err = regmap_read(regmap, AMC6821_REG_CONF4, &regval);
 439                 if (err)
 440                         return err;
 441                 *val = (regval & AMC6821_CONF4_PSPR) ? 4 : 2;
 442                 return 0;
 443         default:
 444                 return -EOPNOTSUPP;
 445         }
 446 }
 447
 448 static int amc6821_fan_write(struct device *dev, u32 attr, long val)
 449 {
 450         struct amc6821_data *data = dev_get_drvdata(dev);
 451         struct regmap *regmap = data->regmap;
 452         u8 regs[2];
 453         int reg;
 454
 455         if (attr == hwmon_fan_pulses) {
 456                 if (val != 2 && val != 4)
 457                         return -EINVAL;
 458                 return regmap_update_bits(regmap, AMC6821_REG_CONF4,
 459                                          AMC6821_CONF4_PSPR,
 460                                          val == 4 ? AMC6821_CONF4_PSPR : 0);
 461         }
 462
 463         if (val < 0)
 464                 return -EINVAL;
 465
 466         switch (attr) {
 467         case hwmon_fan_min:
 468                 if (!val)       /* no unlimited minimum speed */
 469                         return -EINVAL;
 470                 reg = AMC6821_REG_TACH_LLIMITL;
 471                 break;
 472         case hwmon_fan_max:
 473                 reg = AMC6821_REG_TACH_HLIMITL;
 474                 break;
 475         case hwmon_fan_target:
 476                 if (!val)       /* no unlimited target speed */
 477                         return -EINVAL;
 478                 reg = AMC6821_REG_TACH_SETTINGL;
 479                 break;
 480         default:
 481                 return -EOPNOTSUPP;
 482         }
 483
 484         val = val ? 6000000 / clamp_val(val, 1, 6000000) : 0;
 485         val = clamp_val(val, 0, 0xffff);
 486
 487         regs[0] = val & 0xff;
 488         regs[1] = val >> 8;
 489
 490         return regmap_bulk_write(data->regmap, reg, regs, 2);
 491 }
 492
 493 static ssize_t temp_auto_point_temp_show(struct device *dev,
 494                                          struct device_attribute *devattr,
 495                                          char *buf)
 496 {
 497         struct amc6821_data *data = dev_get_drvdata(dev);
 498         int ix = to_sensor_dev_attr_2(devattr)->index;
 499         int nr = to_sensor_dev_attr_2(devattr)->nr;
 500         u8 temps[3];
 501         int err;
 502
 503         mutex_lock(&data->update_lock);
 504         err = amc6821_get_auto_point_temps(data->regmap, nr, temps);
 505         mutex_unlock(&data->update_lock);
 506         if (err)
 507                 return err;
 508
 509         return sysfs_emit(buf, "%d\n", temps[ix] * 1000);
 510 }
 511
 512 static ssize_t pwm1_auto_point_pwm_show(struct device *dev,
 513                                         struct device_attribute *devattr,
 514                                         char *buf)
 515 {
 516         struct amc6821_data *data = dev_get_drvdata(dev);
 517         int ix = to_sensor_dev_attr(devattr)->index;
 518         u32 val;
 519         int err;
 520
 521         switch (ix) {
 522         case 0:
 523                 val = 0;
 524                 break;
 525         case 1:
 526                 err = regmap_read(data->regmap, AMC6821_REG_DCY_LOW_TEMP, &val);
 527                 if (err)
 528                         return err;
 529                 break;
 530         default:
 531                 val = 255;
 532                 break;
 533         }
 534         return sysfs_emit(buf, "%d\n", val);
 535 }
 536
 537 /*
 538  * Set TEMP[0-4] (low temperature) and SLP[0-2] (slope) of local or remote
 539  * TEMP-FAN control register.
 540  *
 541  * Return 0 on success or negative error code.
 542  *
 543  * Channel 0: local, channel 1: remote
 544  */
 545 static inline int set_slope_register(struct regmap *regmap, int channel, u8 *temps)
 546 {
 547         u8 regval = FIELD_PREP(AMC6821_TEMP_LIMIT_MASK, temps[1] / 4);
 548         u8 tmp, dpwm;
 549         int err, dt;
 550         u32 pwm;
 551
 552         err = regmap_read(regmap, AMC6821_REG_DCY_LOW_TEMP, &pwm);
 553         if (err)
 554                 return err;
 555
 556         dpwm = 255 - pwm;
 557
 558         dt = temps[2] - temps[1];
 559         for (tmp = 4; tmp > 0; tmp--) {
 560                 if (dt * (32 >> tmp) >= dpwm)
 561                         break;
 562         }
 563         regval |= FIELD_PREP(AMC6821_TEMP_SLOPE_MASK, tmp);
 564
 565         return regmap_write(regmap,
 566                             channel ? AMC6821_REG_RTEMP_FAN_CTRL : AMC6821_REG_LTEMP_FAN_CTRL,
 567                             regval);
 568 }
 569
 570 static ssize_t temp_auto_point_temp_store(struct device *dev,
 571                                           struct device_attribute *attr,
 572                                           const char *buf, size_t count)
 573 {
 574         struct amc6821_data *data = dev_get_drvdata(dev);
 575         int ix = to_sensor_dev_attr_2(attr)->index;
 576         int nr = to_sensor_dev_attr_2(attr)->nr;
 577         struct regmap *regmap = data->regmap;
 578         u8 temps[3], otemps[3];
 579         long val;
 580         int ret;
 581
 582         ret = kstrtol(buf, 10, &val);
 583         if (ret)
 584                 return ret;
 585
 586         mutex_lock(&data->update_lock);
 587
 588         ret = amc6821_get_auto_point_temps(data->regmap, nr, temps);
 589         if (ret)
 590                 goto unlock;
 591
 592         switch (ix) {
 593         case 0:
 594                 /*
 595                  * Passive cooling temperature. Range limit against low limit
 596                  * of both channels.
 597                  */
 598                 ret = amc6821_get_auto_point_temps(data->regmap, 1 - nr, otemps);
 599                 if (ret)
 600                         goto unlock;
 601                 val = DIV_ROUND_CLOSEST(clamp_val(val, 0, 63000), 1000);
 602                 val = clamp_val(val, 0, min(temps[1], otemps[1]));
 603                 ret = regmap_write(regmap, AMC6821_REG_PSV_TEMP, val);
 604                 break;
 605         case 1:
 606                 /*
 607                  * Low limit; must be between passive and high limit,
 608                  * and not exceed 124. Step size is 4 degrees C.
 609                  */
 610                 val = clamp_val(val, DIV_ROUND_UP(temps[0], 4) * 4000, 124000);
 611                 temps[1] = DIV_ROUND_CLOSEST(val, 4000) * 4;
 612                 val = temps[1] / 4;
 613                 /* Auto-adjust high limit if necessary */
 614                 temps[2] = clamp_val(temps[2], temps[1] + 1, 255);
 615                 ret = set_slope_register(regmap, nr, temps);
 616                 break;
 617         case 2:
 618                 /* high limit, must be higher than low limit */
 619                 val = clamp_val(val, (temps[1] + 1) * 1000, 255000);
 620                 temps[2] = DIV_ROUND_CLOSEST(val, 1000);
 621                 ret = set_slope_register(regmap, nr, temps);
 622                 break;
 623         default:
 624                 ret = -EINVAL;
 625                 break;
 626         }
 627 unlock:
 628         mutex_unlock(&data->update_lock);
 629         return ret ? : count;
 630 }
 631
 632 static ssize_t pwm1_auto_point_pwm_store(struct device *dev,
 633                                          struct device_attribute *attr,
 634                                          const char *buf, size_t count)
 635 {
 636         struct amc6821_data *data = dev_get_drvdata(dev);
 637         struct regmap *regmap = data->regmap;
 638         int i, ret;
 639         u8 val;
 640
 641         ret = kstrtou8(buf, 10, &val);
 642         if (ret)
 643                 return ret;
 644
 645         mutex_lock(&data->update_lock);
 646         ret = regmap_write(regmap, AMC6821_REG_DCY_LOW_TEMP, val);
 647         if (ret)
 648                 goto unlock;
 649
 650         for (i = 0; i < 2; i++) {
 651                 u8 temps[3];
 652
 653                 ret = amc6821_get_auto_point_temps(regmap, i, temps);
 654                 if (ret)
 655                         break;
 656                 ret = set_slope_register(regmap, i, temps);
 657                 if (ret)
 658                         break;
 659         }
 660 unlock:
 661         mutex_unlock(&data->update_lock);
 662         return ret ? : count;
 663 }
 664
 665 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point1_pwm, pwm1_auto_point_pwm, 0);
 666 static SENSOR_DEVICE_ATTR_RW(pwm1_auto_point2_pwm, pwm1_auto_point_pwm, 1);
 667 static SENSOR_DEVICE_ATTR_RO(pwm1_auto_point3_pwm, pwm1_auto_point_pwm, 2);
 668 static SENSOR_DEVICE_ATTR_2_RO(temp1_auto_point1_temp, temp_auto_point_temp,
 669                                0, 0);
 670 static SENSOR_DEVICE_ATTR_2_RW(temp1_auto_point2_temp, temp_auto_point_temp,
 671                                0, 1);
 672 static SENSOR_DEVICE_ATTR_2_RW(temp1_auto_point3_temp, temp_auto_point_temp,
 673                                0, 2);
 674
 675 static SENSOR_DEVICE_ATTR_2_RW(temp2_auto_point1_temp, temp_auto_point_temp,
 676                                1, 0);
 677 static SENSOR_DEVICE_ATTR_2_RW(temp2_auto_point2_temp, temp_auto_point_temp,
 678                                1, 1);
 679 static SENSOR_DEVICE_ATTR_2_RW(temp2_auto_point3_temp, temp_auto_point_temp,
 680                                1, 2);
 681
 682 static struct attribute *amc6821_attrs[] = {
 683         &sensor_dev_attr_pwm1_auto_point1_pwm.dev_attr.attr,
 684         &sensor_dev_attr_pwm1_auto_point2_pwm.dev_attr.attr,
 685         &sensor_dev_attr_pwm1_auto_point3_pwm.dev_attr.attr,
 686         &sensor_dev_attr_temp1_auto_point1_temp.dev_attr.attr,
 687         &sensor_dev_attr_temp1_auto_point2_temp.dev_attr.attr,
 688         &sensor_dev_attr_temp1_auto_point3_temp.dev_attr.attr,
 689         &sensor_dev_attr_temp2_auto_point1_temp.dev_attr.attr,
 690         &sensor_dev_attr_temp2_auto_point2_temp.dev_attr.attr,
 691         &sensor_dev_attr_temp2_auto_point3_temp.dev_attr.attr,
 692         NULL
 693 };
 694 ATTRIBUTE_GROUPS(amc6821);
 695
 696 static int amc6821_read(struct device *dev, enum hwmon_sensor_types type,
 697                         u32 attr, int channel, long *val)
 698 {
 699         switch (type) {
 700         case hwmon_temp:
 701                 return amc6821_temp_read(dev, attr, channel, val);
 702         case hwmon_fan:
 703                 return amc6821_fan_read(dev, attr, val);
 704         case hwmon_pwm:
 705                 return amc6821_pwm_read(dev, attr, val);
 706         default:
 707                 return -EOPNOTSUPP;
 708         }
 709 }
 710
 711 static int amc6821_write(struct device *dev, enum hwmon_sensor_types type,
 712                          u32 attr, int channel, long val)
 713 {
 714         switch (type) {
 715         case hwmon_temp:
 716                 return amc6821_temp_write(dev, attr, channel, val);
 717         case hwmon_fan:
 718                 return amc6821_fan_write(dev, attr, val);
 719         case hwmon_pwm:
 720                 return amc6821_pwm_write(dev, attr, val);
 721         default:
 722                 return -EOPNOTSUPP;
 723         }
 724 }
 725
 726 static umode_t amc6821_is_visible(const void *data,
 727                                   enum hwmon_sensor_types type,
 728                                   u32 attr, int channel)
 729 {
 730         switch (type) {
 731         case hwmon_temp:
 732                 switch (attr) {
 733                 case hwmon_temp_input:
 734                 case hwmon_temp_min_alarm:
 735                 case hwmon_temp_max_alarm:
 736                 case hwmon_temp_crit_alarm:
 737                 case hwmon_temp_fault:
 738                         return 0444;
 739                 case hwmon_temp_min:
 740                 case hwmon_temp_max:
 741                 case hwmon_temp_crit:
 742                         return 0644;
 743                 default:
 744                         return 0;
 745                 }
 746         case hwmon_fan:
 747                 switch (attr) {
 748                 case hwmon_fan_input:
 749                 case hwmon_fan_fault:
 750                         return 0444;
 751                 case hwmon_fan_pulses:
 752                 case hwmon_fan_min:
 753                 case hwmon_fan_max:
 754                 case hwmon_fan_target:
 755                         return 0644;
 756                 default:
 757                         return 0;
 758                 }
 759         case hwmon_pwm:
 760                 switch (attr) {
 761                 case hwmon_pwm_mode:
 762                 case hwmon_pwm_enable:
 763                 case hwmon_pwm_input:
 764                         return 0644;
 765                 case hwmon_pwm_auto_channels_temp:
 766                         return 0444;
 767                 default:
 768                         return 0;
 769                 }
 770         default:
 771                 return 0;
 772         }
 773 }
 774
 775 static const struct hwmon_channel_info * const amc6821_info[] = {
 776         HWMON_CHANNEL_INFO(temp,
 777                            HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
 778                            HWMON_T_CRIT | HWMON_T_MIN_ALARM |
 779                            HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM,
 780                            HWMON_T_INPUT | HWMON_T_MIN | HWMON_T_MAX |
 781                            HWMON_T_CRIT | HWMON_T_MIN_ALARM |
 782                            HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
 783                            HWMON_T_FAULT),
 784         HWMON_CHANNEL_INFO(fan,
 785                            HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_MAX |
 786                            HWMON_F_TARGET | HWMON_F_PULSES | HWMON_F_FAULT),
 787         HWMON_CHANNEL_INFO(pwm,
 788                            HWMON_PWM_INPUT | HWMON_PWM_ENABLE | HWMON_PWM_MODE |
 789                            HWMON_PWM_AUTO_CHANNELS_TEMP),
 790         NULL
 791 };
 792
 793 static const struct hwmon_ops amc6821_hwmon_ops = {
 794         .is_visible = amc6821_is_visible,
 795         .read = amc6821_read,
 796         .write = amc6821_write,
 797 };
 798
 799 static const struct hwmon_chip_info amc6821_chip_info = {
 800         .ops = &amc6821_hwmon_ops,
 801         .info = amc6821_info,
 802 };
 803
 804 /* Return 0 if detection is successful, -ENODEV otherwise */
 805 static int amc6821_detect(struct i2c_client *client, struct i2c_board_info *info)
 806 {
 807         struct i2c_adapter *adapter = client->adapter;
 808         int address = client->addr;
 809         int dev_id, comp_id;
 810
 811         dev_dbg(&adapter->dev, "amc6821_detect called.\n");
 812
 813         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
 814                 dev_dbg(&adapter->dev,
 815                         "amc6821: I2C bus doesn't support byte mode, "
 816                         "skipping.\n");
 817                 return -ENODEV;
 818         }
 819
 820         dev_id = i2c_smbus_read_byte_data(client, AMC6821_REG_DEV_ID);
 821         comp_id = i2c_smbus_read_byte_data(client, AMC6821_REG_COMP_ID);
 822         if (dev_id != 0x21 || comp_id != 0x49) {
 823                 dev_dbg(&adapter->dev,
 824                         "amc6821: detection failed at 0x%02x.\n",
 825                         address);
 826                 return -ENODEV;
 827         }
 828
 829         /*
 830          * Bit 7 of the address register is ignored, so we can check the
 831          * ID registers again
 832          */
 833         dev_id = i2c_smbus_read_byte_data(client, 0x80 | AMC6821_REG_DEV_ID);
 834         comp_id = i2c_smbus_read_byte_data(client, 0x80 | AMC6821_REG_COMP_ID);
 835         if (dev_id != 0x21 || comp_id != 0x49) {
 836                 dev_dbg(&adapter->dev,
 837                         "amc6821: detection failed at 0x%02x.\n",
 838                         address);
 839                 return -ENODEV;
 840         }
 841
 842         dev_info(&adapter->dev, "amc6821: chip found at 0x%02x.\n", address);
 843         strscpy(info->type, "amc6821", I2C_NAME_SIZE);
 844
 845         return 0;
 846 }
 847
 848 static int amc6821_init_client(struct amc6821_data *data)
 849 {
 850         struct regmap *regmap = data->regmap;
 851         int err;
 852
 853         if (init) {
 854                 err = regmap_set_bits(regmap, AMC6821_REG_CONF4, AMC6821_CONF4_MODE);
 855                 if (err)
 856                         return err;
 857                 err = regmap_clear_bits(regmap, AMC6821_REG_CONF3, AMC6821_CONF3_THERM_FAN_EN);
 858                 if (err)
 859                         return err;
 860                 err = regmap_clear_bits(regmap, AMC6821_REG_CONF2,
 861                                         AMC6821_CONF2_RTFIE |
 862                                         AMC6821_CONF2_LTOIE |
 863                                         AMC6821_CONF2_RTOIE);
 864                 if (err)
 865                         return err;
 866
 867                 err = regmap_update_bits(regmap, AMC6821_REG_CONF1,
 868                                          AMC6821_CONF1_THERMOVIE | AMC6821_CONF1_FANIE |
 869                                          AMC6821_CONF1_START | AMC6821_CONF1_PWMINV,
 870                                          AMC6821_CONF1_START |
 871                                          (pwminv ? AMC6821_CONF1_PWMINV : 0));
 872                 if (err)
 873                         return err;
 874         }
 875         return 0;
 876 }
 877
 878 static bool amc6821_volatile_reg(struct device *dev, unsigned int reg)
 879 {
 880         switch (reg) {
 881         case AMC6821_REG_STAT1:
 882         case AMC6821_REG_STAT2:
 883         case AMC6821_REG_TEMP_LO:
 884         case AMC6821_REG_TDATA_LOW:
 885         case AMC6821_REG_LTEMP_HI:
 886         case AMC6821_REG_RTEMP_HI:
 887         case AMC6821_REG_TDATA_HI:
 888                 return true;
 889         default:
 890                 return false;
 891         }
 892 }
 893
 894 static const struct regmap_config amc6821_regmap_config = {
 895         .reg_bits = 8,
 896         .val_bits = 8,
 897         .volatile_reg = amc6821_volatile_reg,
 898         .cache_type = REGCACHE_MAPLE,
 899 };
 900
 901 static int amc6821_probe(struct i2c_client *client)
 902 {
 903         struct device *dev = &client->dev;
 904         struct amc6821_data *data;
 905         struct device *hwmon_dev;
 906         struct regmap *regmap;
 907         int err;
 908
 909         data = devm_kzalloc(dev, sizeof(struct amc6821_data), GFP_KERNEL);
 910         if (!data)
 911                 return -ENOMEM;
 912
 913         regmap = devm_regmap_init_i2c(client, &amc6821_regmap_config);
 914         if (IS_ERR(regmap))
 915                 return dev_err_probe(dev, PTR_ERR(regmap),
 916                                      "Failed to initialize regmap\n");
 917         data->regmap = regmap;
 918
 919         err = amc6821_init_client(data);
 920         if (err)
 921                 return err;
 922
 923         if (of_device_is_compatible(dev->of_node, "tsd,mule")) {
 924                 err = devm_of_platform_populate(dev);
 925                 if (err)
 926                         return dev_err_probe(dev, err,
 927                                      "Failed to create sub-devices\n");
 928         }
 929
 930         hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 931                                                          data, &amc6821_chip_info,
 932                                                          amc6821_groups);
 933         return PTR_ERR_OR_ZERO(hwmon_dev);
 934 }
 935
 936 static const struct i2c_device_id amc6821_id[] = {
 937         { "amc6821" },
 938         { }
 939 };
 940
 941 MODULE_DEVICE_TABLE(i2c, amc6821_id);
 942
 943 static const struct of_device_id __maybe_unused amc6821_of_match[] = {
 944         {
 945                 .compatible = "ti,amc6821",
 946         },
 947         {
 948                 .compatible = "tsd,mule",
 949         },
 950         { }
 951 };
 952
 953 MODULE_DEVICE_TABLE(of, amc6821_of_match);
 954
 955 static struct i2c_driver amc6821_driver = {
 956         .class = I2C_CLASS_HWMON,
 957         .driver = {
 958                 .name   = "amc6821",
 959                 .of_match_table = of_match_ptr(amc6821_of_match),
 960         },
 961         .probe = amc6821_probe,
 962         .id_table = amc6821_id,
 963         .detect = amc6821_detect,
 964         .address_list = normal_i2c,
 965 };
 966
 967 module_i2c_driver(amc6821_driver);
 968
 969 MODULE_LICENSE("GPL");
 970 MODULE_AUTHOR("T. Mertelj <tomaz.mertelj@guest.arnes.si>");
 971 MODULE_DESCRIPTION("Texas Instruments amc6821 hwmon driver");