target/linux/apm821xx/patches-4.4/901-hwmon-add-driver-for-Microchip-TC654-TC655-PWM-fan-c.patch

   1 From 5ea2e152d846bf60901107fefd81a58f792f3bc2 Mon Sep 17 00:00:00 2001
   2 From: Christian Lamparter <chunkeey@gmail.com>
   3 Date: Fri, 10 Jun 2016 03:00:46 +0200
   4 Subject: [PATCH] hwmon: add driver for Microchip TC654/TC655 PWM fan
   5  controllers
   6
   7 This patch adds a hwmon driver for the Microchip TC654 and TC655
   8 Dual SMBus PWM Fan Speed Controllers with Fan Fault detection.
   9
  10 The chip is described in the DS2001734C Spec Document from Microchip.
  11 It supports:
  12         - Shared PWM Fan Drive for two fans
  13         - Provides RPM
  14         - automatic PWM controller (needs additional
  15           NTC/PTC Thermistors.)
  16         - Overtemperature alarm (when using NTC/PTC
  17           Thermistors)
  18
  19 Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
  20 ---
  21  drivers/hwmon/Kconfig  |  10 +
  22  drivers/hwmon/Makefile |   1 +
  23  drivers/hwmon/tc654.c  | 969 +++++++++++++++++++++++++++++++++++++++++++++++++
  24  3 files changed, 980 insertions(+)
  25  create mode 100644 drivers/hwmon/tc654.c
  26
  27 --- a/drivers/hwmon/Kconfig
  28 +++ b/drivers/hwmon/Kconfig
  29 @@ -1493,6 +1493,16 @@ config SENSORS_INA2XX
  30           This driver can also be built as a module.  If so, the module
  31           will be called ina2xx.
  32
  33 +config SENSORS_TC654
  34 +       tristate "Microchip TC654 and TC655"
  35 +       depends on I2C
  36 +       help
  37 +         If you say yes here you get support for Microchip TC655 and TC654
  38 +         Dual PWM Fan Speed Controllers and sensor chips.
  39 +
  40 +         This driver can also be built as a module.  If so, the module
  41 +         will be called tc654.
  42 +
  43  config SENSORS_TC74
  44         tristate "Microchip TC74"
  45         depends on I2C
  46 --- a/drivers/hwmon/Makefile
  47 +++ b/drivers/hwmon/Makefile
  48 @@ -143,6 +143,7 @@ obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc4
  49  obj-$(CONFIG_SENSORS_SMSC47M1) += smsc47m1.o
  50  obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
  51  obj-$(CONFIG_SENSORS_AMC6821)  += amc6821.o
  52 +obj-$(CONFIG_SENSORS_TC654)    += tc654.o
  53  obj-$(CONFIG_SENSORS_TC74)     += tc74.o
  54  obj-$(CONFIG_SENSORS_THMC50)   += thmc50.o
  55  obj-$(CONFIG_SENSORS_TMP102)   += tmp102.o
  56 --- /dev/null
  57 +++ b/drivers/hwmon/tc654.c
  58 @@ -0,0 +1,969 @@
  59 +/*
  60 + * tc654.c - Support for Microchip TC654/TC655
  61 + * "A Dual SMBus PWM FAN Speed Controllers with Fan Fault Detection"
  62 + *
  63 + * Copyright (c) 2016 Christian Lamparter <chunkeey@gmail.com>
  64 + *
  65 + * This program is free software; you can redistribute it and/or modify
  66 + * it under the terms of the GNU General Public License as published by
  67 + * the Free Software Foundation version 2 of the License.
  68 + *
  69 + * This program is distributed in the hope that it will be useful,
  70 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  71 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  72 + * GNU General Public License for more details.
  73 + *
  74 + * The chip is described in the DS2001734C Spec Document from Microchip.
  75 + */
  76 +
  77 +#include <linux/module.h>
  78 +#include <linux/init.h>
  79 +#include <linux/slab.h>
  80 +#include <linux/jiffies.h>
  81 +#include <linux/i2c.h>
  82 +#include <linux/hwmon.h>
  83 +#include <linux/hwmon-sysfs.h>
  84 +#include <linux/err.h>
  85 +#include <linux/mutex.h>
  86 +#include <linux/thermal.h>
  87 +
  88 +/* Hardware definitions */
  89 +/* 5.1.4 Address Byte stats that TC654/TC655 are fixed at 0x1b */
  90 +static const unsigned short normal_i2c[] = { 0x1b, I2C_CLIENT_END };
  91 +
  92 +enum TC654_REGS {
  93 +       TC654_REG_RPM1 = 0x00,
  94 +       TC654_REG_RPM2,
  95 +       TC654_REG_FAN1_FAULT_THRESH,
  96 +       TC654_REG_FAN2_FAULT_THRESH,
  97 +       TC654_REG_CONFIG,
  98 +       TC654_REG_STATUS,
  99 +       TC654_REG_DUTY_CYCLE,
 100 +       TC654_REG_MFR_ID,
 101 +       TC654_REG_VER_ID,
 102 +
 103 +       /* keep last */
 104 +       __TC654_REG_NUM,
 105 +};
 106 +
 107 +#define TC654_MFR_ID_MICROCHIP         0x84
 108 +#define TC654_VER_ID                   0x00
 109 +#define TC655_VER_ID                   0x01
 110 +
 111 +enum TC654_CONTROL_BITS {
 112 +       TC654_CTRL_SDM          = BIT(0),
 113 +       TC654_CTRL_F1PPR_S      = 1,
 114 +       TC654_CTRL_F1PPR_M      = (BIT(1) | BIT(2)),
 115 +       TC654_CTRL_F2PPR_S      = 3,
 116 +       TC654_CTRL_F2PPR_M      = (BIT(3) | BIT(4)),
 117 +       TC654_CTRL_DUTYC        = BIT(5),
 118 +       TC654_CTRL_RES          = BIT(6),
 119 +       TC654_CTRL_FFCLR        = BIT(7),
 120 +};
 121 +
 122 +enum TC654_STATUS_BITS {
 123 +       TC654_STATUS_F1F        = BIT(0),
 124 +       TC654_STATUS_F2F        = BIT(1),
 125 +       TC654_STATUS_VSTAT      = BIT(2),
 126 +       TC654_STATUS_R1CO       = BIT(3),
 127 +       TC654_STATUS_R2CO       = BIT(4),
 128 +       TC654_STATUS_OTF        = BIT(5),
 129 +};
 130 +
 131 +enum TC654_FAN {
 132 +       TC654_FAN1 = 0,
 133 +       TC654_FAN2,
 134 +
 135 +       /* keep last */
 136 +       __NUM_TC654_FAN,
 137 +};
 138 +
 139 +enum TC654_FAN_MODE {
 140 +       TC654_PWM_OFF,  /* Shutdown Mode - switch of both fans */
 141 +       TC654_PWM_VIN,  /* Fans will be controlled via V_in analog input pin */
 142 +       TC654_PWM_3000, /* sets fans to 30% duty cycle */
 143 +       TC654_PWM_3467,
 144 +       TC654_PWM_3933, /* default case - if V_in pin is open */
 145 +       TC654_PWM_4400,
 146 +       TC654_PWM_4867,
 147 +       TC654_PWM_5333,
 148 +       TC654_PWM_5800,
 149 +       TC654_PWM_6267,
 150 +       TC654_PWM_6733,
 151 +       TC654_PWM_7200,
 152 +       TC654_PWM_7667,
 153 +       TC654_PWM_8133,
 154 +       TC654_PWM_8600,
 155 +       TC654_PWM_9067,
 156 +       TC654_PWM_9533,
 157 +       TC654_PWM_10000, /* sets fans to 100% duty cycle */
 158 +};
 159 +
 160 +enum TC654_ALARMS {
 161 +       TC654_ALARM_FAN1_FAULT,
 162 +       TC654_ALARM_FAN2_FAULT,
 163 +       TC654_ALARM_FAN1_COUNTER_OVERFLOW,
 164 +       TC654_ALARM_FAN2_COUNTER_OVERFLOW,
 165 +       TC654_ALARM_OVER_TEMPERATURE,
 166 +
 167 +       /* KEEP LAST */
 168 +       __NUM_TC654_ALARMS,
 169 +};
 170 +
 171 +static const struct pwm_table_entry {
 172 +       u8 min;
 173 +       enum TC654_FAN_MODE mode;
 174 +} pwm_table[] = {
 175 +       {  0, TC654_PWM_OFF  },
 176 +       {  1, TC654_PWM_3000 },
 177 +       { 88, TC654_PWM_3467 },
 178 +       {101, TC654_PWM_3933 },
 179 +       {113, TC654_PWM_4400 },
 180 +       {125, TC654_PWM_4867 },
 181 +       {137, TC654_PWM_5333 },
 182 +       {148, TC654_PWM_5800 },
 183 +       {160, TC654_PWM_6267 },
 184 +       {172, TC654_PWM_6733 },
 185 +       {184, TC654_PWM_7200 },
 186 +       {196, TC654_PWM_7667 },
 187 +       {208, TC654_PWM_8133 },
 188 +       {220, TC654_PWM_8600 },
 189 +       {232, TC654_PWM_9067 },
 190 +       {244, TC654_PWM_9533 },
 191 +       {255, TC654_PWM_10000 },
 192 +};
 193 +
 194 +/* driver context */
 195 +struct tc654 {
 196 +       struct i2c_client       *client;
 197 +
 198 +       struct mutex            update_lock;
 199 +
 200 +       unsigned long           last_updated;   /* in jiffies */
 201 +       u8                      cached_regs[__TC654_REG_NUM];
 202 +
 203 +       bool                    valid;  /* monitored registers are valid */
 204 +       u16                     fan_input[__NUM_TC654_FAN];
 205 +       bool                    alarms[__NUM_TC654_ALARMS];
 206 +       bool                    vin_status;
 207 +       bool                    pwm_manual;
 208 +
 209 +       /* optional cooling device */
 210 +       struct thermal_cooling_device *cdev;
 211 +};
 212 +
 213 +/* hardware accessors and functions */
 214 +static int read_tc(struct tc654 *tc, u8 reg)
 215 +{
 216 +       s32 status;
 217 +
 218 +       if (reg <= TC654_REG_VER_ID) {
 219 +               /* Table 6.1 states that all registers are readable */
 220 +               status = i2c_smbus_read_byte_data(tc->client, reg);
 221 +       } else
 222 +               status = -EINVAL;
 223 +
 224 +       if (status < 0) {
 225 +               dev_warn(&tc->client->dev, "can't read register 0x%02x due to error (%d)",
 226 +                        reg, status);
 227 +       } else {
 228 +               tc->cached_regs[reg] = status;
 229 +       }
 230 +
 231 +       return status;
 232 +}
 233 +
 234 +static int write_tc(struct tc654 *tc, u8 i2c_reg, u8 val)
 235 +{
 236 +       s32 status;
 237 +
 238 +       /*
 239 +        * Table 6.1 states that both fan threshold registers,
 240 +        * the Config and Duty Cycle are writeable.
 241 +        */
 242 +       switch (i2c_reg) {
 243 +       case TC654_REG_FAN1_FAULT_THRESH:
 244 +       case TC654_REG_FAN2_FAULT_THRESH:
 245 +       case TC654_REG_DUTY_CYCLE:
 246 +       case TC654_REG_CONFIG:
 247 +               status = i2c_smbus_write_byte_data(tc->client, i2c_reg, val);
 248 +               break;
 249 +
 250 +       default:
 251 +               return -EINVAL;
 252 +       }
 253 +
 254 +       if (status < 0) {
 255 +               dev_warn(&tc->client->dev, "can't write register 0x%02x with value 0x%02x due to error (%d)",
 256 +                        i2c_reg, val, status);
 257 +       } else {
 258 +               tc->cached_regs[i2c_reg] = val;
 259 +       }
 260 +
 261 +       return status;
 262 +}
 263 +
 264 +static int mod_config(struct tc654 *tc, u8 set, u8 clear)
 265 +{
 266 +       u8 val = 0;
 267 +
 268 +       /* a bit can't be set and cleared on the same time. */
 269 +       if (set & clear)
 270 +               return -EINVAL;
 271 +
 272 +       /* invalidate data to force re-read from hardware */
 273 +       tc->valid = false;
 274 +       val = (tc->cached_regs[TC654_REG_CONFIG] | set) & (~clear);
 275 +       return write_tc(tc, TC654_REG_CONFIG, val);
 276 +}
 277 +
 278 +static int read_fan_rpm(struct tc654 *tc, enum TC654_FAN fan)
 279 +{
 280 +       int ret;
 281 +
 282 +       /* 6.1 RPM-OUTPUT1 and RPM-OUTPUT2 registers */
 283 +       ret = read_tc(tc, fan == TC654_FAN1 ? TC654_REG_RPM1 : TC654_REG_RPM2);
 284 +       if (ret < 0)
 285 +               return ret;
 286 +
 287 +       /*
 288 +        * The Resolution Selection Bit in 6.3 CONFIGURATION REGISTER
 289 +        * is needed to convert the raw value to the RPM.
 290 +        * 0 = RPM1 and RPM2 use (8-Bit) resolution => * 50 RPM
 291 +        * 1 = RPM1 and RPM2 use (9-Bit) resolution => * 25 RPM
 292 +        */
 293 +       return ret * (25 <<
 294 +               !(tc->cached_regs[TC654_REG_CONFIG] & TC654_CTRL_RES));
 295 +}
 296 +
 297 +static int write_fan_fault_thresh(struct tc654 *tc, enum TC654_FAN fan,
 298 +                                 u16 rpm)
 299 +{
 300 +       u8 converted_rpm;
 301 +
 302 +       if (rpm > 12750)
 303 +               return -EINVAL;
 304 +
 305 +       /*
 306 +        * 6.2 FAN_FAULT1 and FAN_FAULT2 Threshold registers
 307 +        *
 308 +        * Both registers operate in 50 RPM mode exclusively.
 309 +        */
 310 +       converted_rpm = rpm / 50;
 311 +
 312 +       /* invalidate data to force re-read from hardware */
 313 +       tc->valid = false;
 314 +       return write_tc(tc, fan == TC654_FAN1 ? TC654_REG_FAN1_FAULT_THRESH :
 315 +               TC654_REG_FAN2_FAULT_THRESH, converted_rpm);
 316 +}
 317 +
 318 +
 319 +static int read_fan_fault_thresh(struct tc654 *tc, enum TC654_FAN fan)
 320 +{
 321 +       /*
 322 +        * 6.2 FAN_FAULT1 and FAN_FAULT2 Threshold registers
 323 +        *
 324 +        * Both registers operate in 50 RPM mode exclusively.
 325 +        */
 326 +       return read_tc(tc, fan == TC654_FAN1 ? TC654_REG_FAN1_FAULT_THRESH :
 327 +               TC654_REG_FAN2_FAULT_THRESH) * 50;
 328 +}
 329 +
 330 +static enum TC654_FAN_MODE get_fan_mode(struct tc654 *tc)
 331 +{
 332 +       if (tc->cached_regs[TC654_REG_CONFIG] & TC654_CTRL_SDM) {
 333 +               return TC654_PWM_OFF;
 334 +       } else if (tc->cached_regs[TC654_REG_CONFIG] & TC654_CTRL_DUTYC) {
 335 +               return TC654_PWM_3000 + tc->cached_regs[TC654_REG_DUTY_CYCLE];
 336 +       } else if (tc->vin_status == 0)
 337 +               return TC654_PWM_VIN;
 338 +
 339 +       return -EINVAL;
 340 +}
 341 +
 342 +static int write_fan_mode(struct tc654 *tc, enum TC654_FAN_MODE mode)
 343 +{
 344 +       int err;
 345 +       u8 pwm_mode;
 346 +       bool in_sdm;
 347 +
 348 +       in_sdm = !!(tc->cached_regs[TC654_REG_CONFIG] &
 349 +               TC654_CTRL_SDM);
 350 +
 351 +       switch (mode) {
 352 +       case TC654_PWM_OFF:
 353 +               if (in_sdm)
 354 +                       return 0;
 355 +
 356 +               /* Enter Shutdown Mode - Switches off all fans */
 357 +               err = mod_config(tc, TC654_CTRL_SDM, TC654_CTRL_DUTYC);
 358 +               if (err)
 359 +                       return err;
 360 +
 361 +               return 0;
 362 +
 363 +       case TC654_PWM_VIN:
 364 +               if (tc->vin_status) {
 365 +                       dev_err(&tc->client->dev,
 366 +                               "V_in pin is open, can't enable automatic mode.");
 367 +                       return -EINVAL;
 368 +               }
 369 +
 370 +               err = mod_config(tc, 0, TC654_CTRL_SDM | TC654_CTRL_DUTYC);
 371 +               if (err)
 372 +                       return err;
 373 +
 374 +               tc->pwm_manual = false;
 375 +               return 0;
 376 +
 377 +       case TC654_PWM_3000:
 378 +       case TC654_PWM_3467:
 379 +       case TC654_PWM_3933:
 380 +       case TC654_PWM_4400:
 381 +       case TC654_PWM_4867:
 382 +       case TC654_PWM_5333:
 383 +       case TC654_PWM_5800:
 384 +       case TC654_PWM_6267:
 385 +       case TC654_PWM_6733:
 386 +       case TC654_PWM_7200:
 387 +       case TC654_PWM_7667:
 388 +       case TC654_PWM_8133:
 389 +       case TC654_PWM_8600:
 390 +       case TC654_PWM_9067:
 391 +       case TC654_PWM_9533:
 392 +       case TC654_PWM_10000:
 393 +               pwm_mode = mode - TC654_PWM_3000;
 394 +               if (!in_sdm) {
 395 +                       err = write_tc(tc, TC654_REG_DUTY_CYCLE, pwm_mode);
 396 +                       if (err)
 397 +                               return err;
 398 +               }
 399 +
 400 +               err = mod_config(tc, TC654_CTRL_DUTYC, TC654_CTRL_SDM);
 401 +               if (err)
 402 +                       return err;
 403 +
 404 +               tc->pwm_manual = true;
 405 +
 406 +               if (in_sdm) {
 407 +                       /*
 408 +                        * In case the TC654/TC655 was in SDM mode, the write
 409 +                        * above into the TC654_REG_DUTY_CYCLE register will
 410 +                        * have no effect because the chip was switched off.
 411 +                        *
 412 +                        * Note: The TC654/TC655 have a special "power-on"
 413 +                        * feature where the PWM will be forced to 100% for
 414 +                        * one full second in order to spin-up a resting fan.
 415 +                        */
 416 +                       err = write_tc(tc, TC654_REG_DUTY_CYCLE, pwm_mode);
 417 +                       if (err)
 418 +                               return err;
 419 +               }
 420 +
 421 +               return 0;
 422 +
 423 +       default:
 424 +               return -EINVAL;
 425 +       }
 426 +}
 427 +
 428 +static struct tc654 *tc654_update_device(struct device *dev)
 429 +{
 430 +       struct tc654 *tc = dev_get_drvdata(dev);
 431 +
 432 +       mutex_lock(&tc->update_lock);
 433 +
 434 +       /*
 435 +        * In Chapter "1.0 Electrical Characteristics",
 436 +        * the "Fault Output Response Time" is specified as 2.4 seconds.
 437 +        */
 438 +       if (time_after(jiffies, tc->last_updated + 2 * HZ + (HZ * 2) / 5)
 439 +           || !tc->valid) {
 440 +               size_t i;
 441 +               int ret;
 442 +               bool alarm_triggered;
 443 +
 444 +               tc->valid = false;
 445 +
 446 +               for (i = 0; i < __NUM_TC654_FAN; i++) {
 447 +                       ret = read_fan_rpm(tc, i);
 448 +                       if (ret < 0)
 449 +                               goto out;
 450 +
 451 +                       tc->fan_input[i] = ret;
 452 +               }
 453 +
 454 +               ret = read_tc(tc, TC654_REG_STATUS);
 455 +               if (ret < 0)
 456 +                       goto out;
 457 +
 458 +               alarm_triggered = !!(ret & (TC654_STATUS_F1F |
 459 +                       TC654_STATUS_F2F | TC654_STATUS_R1CO |
 460 +                       TC654_STATUS_R2CO | TC654_STATUS_OTF));
 461 +
 462 +               tc->alarms[TC654_ALARM_FAN1_FAULT] = !!(ret & TC654_STATUS_F1F);
 463 +               tc->alarms[TC654_ALARM_FAN2_FAULT] = !!(ret & TC654_STATUS_F2F);
 464 +               tc->alarms[TC654_ALARM_FAN1_COUNTER_OVERFLOW] =
 465 +                       !!(ret & TC654_STATUS_R1CO);
 466 +               tc->alarms[TC654_ALARM_FAN2_COUNTER_OVERFLOW] =
 467 +                       !!(ret & TC654_STATUS_R2CO);
 468 +               tc->alarms[TC654_ALARM_OVER_TEMPERATURE] =
 469 +                       !!(ret & TC654_STATUS_OTF);
 470 +               tc->vin_status = !!(ret & TC654_STATUS_VSTAT);
 471 +
 472 +               /*
 473 +                * From 4.5 and 6.3
 474 +                *
 475 +                * ... "If the V_in pin is open when TC654_CTRL_DUTYC is not
 476 +                * selected, then V_out duty cycle will default to 39.33%.".
 477 +                *
 478 +                * and most importantly 6.5:
 479 +                * ... "V_in pin is open, the duty cycle will go to the default
 480 +                * setting of this register, which is 0010 (39.33%)."
 481 +                */
 482 +               tc->pwm_manual |= tc->vin_status &&
 483 +                       (tc->cached_regs[TC654_REG_CONFIG] &
 484 +                        TC654_CTRL_DUTYC);
 485 +
 486 +               if (alarm_triggered) {
 487 +                       /*
 488 +                        * as the name implies, this FLAG needs to be
 489 +                        * set in order to clear the FAN Fault error.
 490 +                        */
 491 +                       ret = mod_config(tc, TC654_CTRL_FFCLR, 0);
 492 +                       if (ret < 0)
 493 +                               goto out;
 494 +               }
 495 +
 496 +               tc->last_updated = jiffies;
 497 +               tc->valid = true;
 498 +       }
 499 +
 500 +out:
 501 +       mutex_unlock(&tc->update_lock);
 502 +       return tc;
 503 +}
 504 +
 505 +static u8 get_fan_pulse(struct tc654 *tc, enum TC654_FAN fan)
 506 +{
 507 +       u8 fan_pulse_mask = fan == TC654_FAN1 ?
 508 +               TC654_CTRL_F1PPR_M : TC654_CTRL_F2PPR_M;
 509 +       u8 fan_pulse_shift = fan  == TC654_FAN1 ?
 510 +               TC654_CTRL_F1PPR_S : TC654_CTRL_F2PPR_S;
 511 +
 512 +       return 1 << ((tc->cached_regs[TC654_REG_CONFIG] & fan_pulse_mask) >>
 513 +                    fan_pulse_shift);
 514 +}
 515 +
 516 +static int
 517 +set_fan_pulse(struct tc654 *tc, enum TC654_FAN fan, int pulses)
 518 +{
 519 +       int old_pulses;
 520 +       int err;
 521 +       u8 new_pulse_per_rotation;
 522 +       u8 fan_pulse_mask = fan == TC654_FAN1 ?
 523 +               TC654_CTRL_F1PPR_M : TC654_CTRL_F2PPR_M;
 524 +       u8 fan_pulse_shift = fan  == TC654_FAN1 ?
 525 +               TC654_CTRL_F1PPR_S : TC654_CTRL_F2PPR_S;
 526 +
 527 +       switch (pulses) {
 528 +       case 1:
 529 +               new_pulse_per_rotation = 0;
 530 +               break;
 531 +       case 2:
 532 +               new_pulse_per_rotation = 1;
 533 +               break;
 534 +       case 4:
 535 +               new_pulse_per_rotation = 2;
 536 +               break;
 537 +       case 8:
 538 +               new_pulse_per_rotation = 3;
 539 +               break;
 540 +       default:
 541 +               return -EINVAL;
 542 +       }
 543 +
 544 +       new_pulse_per_rotation <<= fan_pulse_shift;
 545 +       new_pulse_per_rotation &= fan_pulse_mask;
 546 +
 547 +       old_pulses = tc->cached_regs[TC654_REG_CONFIG];
 548 +       old_pulses &= fan_pulse_mask;
 549 +
 550 +       if (new_pulse_per_rotation == old_pulses)
 551 +               return 0;
 552 +
 553 +       mutex_lock(&tc->update_lock);
 554 +       err = mod_config(tc, new_pulse_per_rotation,
 555 +                           old_pulses & (~new_pulse_per_rotation));
 556 +       mutex_unlock(&tc->update_lock);
 557 +
 558 +       /* invalidate RPM data to force re-read from hardware */
 559 +       tc->valid = false;
 560 +
 561 +       return err;
 562 +}
 563 +
 564 +static int get_fan_speed(struct tc654 *tc)
 565 +{
 566 +       enum TC654_FAN_MODE mode;
 567 +       size_t i;
 568 +
 569 +       mode = get_fan_mode(tc);
 570 +       for (i = 0; i < ARRAY_SIZE(pwm_table); i++) {
 571 +               if (mode == pwm_table[i].mode)
 572 +                       return pwm_table[i].min;
 573 +       }
 574 +
 575 +       return -EINVAL;
 576 +}
 577 +
 578 +static int set_fan_speed(struct tc654 *tc, int new_value)
 579 +{
 580 +       int result;
 581 +       size_t i;
 582 +
 583 +       if (new_value > pwm_table[ARRAY_SIZE(pwm_table) - 1].min ||
 584 +           new_value < pwm_table[0].min)
 585 +               return -EINVAL;
 586 +
 587 +       for (i = 0; i < ARRAY_SIZE(pwm_table); i++) {
 588 +               /* exact match */
 589 +               if (pwm_table[i].min == new_value)
 590 +                       break;
 591 +
 592 +               /* a little bit too big - go with the previous entry */
 593 +               if (pwm_table[i].min > new_value) {
 594 +                       --i;
 595 +                       break;
 596 +               }
 597 +       }
 598 +
 599 +       mutex_lock(&tc->update_lock);
 600 +       result = write_fan_mode(tc, pwm_table[i].mode);
 601 +       mutex_unlock(&tc->update_lock);
 602 +       if (result < 0)
 603 +               return result;
 604 +
 605 +       return 0;
 606 +}
 607 +
 608 +/* sysfs */
 609 +
 610 +static ssize_t
 611 +show_fan_input(struct device *dev, struct device_attribute *da, char *buf)
 612 +{
 613 +       struct tc654 *tc = tc654_update_device(dev);
 614 +       int nr = to_sensor_dev_attr(da)->index;
 615 +
 616 +       return sprintf(buf, "%d\n", tc->fan_input[nr]);
 617 +}
 618 +
 619 +static ssize_t
 620 +show_fan_min(struct device *dev, struct device_attribute *da, char *buf)
 621 +{
 622 +       struct tc654 *tc = dev_get_drvdata(dev);
 623 +       int nr = to_sensor_dev_attr(da)->index;
 624 +
 625 +       return sprintf(buf, "%d\n", read_fan_fault_thresh(tc, nr));
 626 +}
 627 +
 628 +static ssize_t
 629 +show_fan_min_alarm(struct device *dev, struct device_attribute *da, char *buf)
 630 +{
 631 +       struct tc654 *tc = tc654_update_device(dev);
 632 +       int nr = to_sensor_dev_attr(da)->index;
 633 +
 634 +       return sprintf(buf, "%d\n", nr == TC654_FAN1 ?
 635 +                      tc->alarms[TC654_ALARM_FAN1_FAULT] :
 636 +                      tc->alarms[TC654_ALARM_FAN2_FAULT]);
 637 +}
 638 +
 639 +static ssize_t
 640 +show_fan_max_alarm(struct device *dev, struct device_attribute *da, char *buf)
 641 +{
 642 +       struct tc654 *tc = tc654_update_device(dev);
 643 +       int nr = to_sensor_dev_attr(da)->index;
 644 +
 645 +       return sprintf(buf, "%d\n", nr == TC654_FAN1 ?
 646 +                      tc->alarms[TC654_ALARM_FAN1_COUNTER_OVERFLOW] :
 647 +                      tc->alarms[TC654_ALARM_FAN2_COUNTER_OVERFLOW]);
 648 +}
 649 +
 650 +static ssize_t
 651 +set_fan_min(struct device *dev, struct device_attribute *da,
 652 +           const char *buf, size_t count)
 653 +{
 654 +       struct tc654 *tc = dev_get_drvdata(dev);
 655 +       long new_min;
 656 +       int nr = to_sensor_dev_attr(da)->index;
 657 +       int old_min = read_fan_fault_thresh(tc, nr);
 658 +       int status = kstrtol(buf, 10, &new_min);
 659 +
 660 +       if (status < 0)
 661 +               return status;
 662 +
 663 +       new_min = (new_min / 50) * 50;
 664 +       if (new_min == old_min) /* No change */
 665 +               return count;
 666 +
 667 +       if (new_min < 0 || new_min > 12750)
 668 +               return -EINVAL;
 669 +
 670 +       mutex_lock(&tc->update_lock);
 671 +       status = write_fan_fault_thresh(tc, nr, new_min);
 672 +       mutex_unlock(&tc->update_lock);
 673 +       return count;
 674 +}
 675 +
 676 +static ssize_t
 677 +show_fan_max(struct device *dev, struct device_attribute *da, char *buf)
 678 +{
 679 +       struct tc654 *tc = dev_get_drvdata(dev);
 680 +       int max_rpm = tc->cached_regs[TC654_REG_CONFIG] & TC654_CTRL_RES ?
 681 +               (((1 << 9) - 1) * 25) /* ((2**9) - 1) * 25 RPM */:
 682 +               (((1 << 8) - 1) * 50) /* ((2**8) - 1) * 50 RPM */;
 683 +
 684 +       return sprintf(buf, "%d\n", max_rpm);
 685 +}
 686 +
 687 +static ssize_t
 688 +show_fan_fault(struct device *dev, struct device_attribute *da, char *buf)
 689 +{
 690 +       struct tc654 *tc = tc654_update_device(dev);
 691 +       int nr = to_sensor_dev_attr(da)->index;
 692 +       u8 fan_fault_mask = nr == TC654_FAN1 ?
 693 +               TC654_STATUS_F1F : TC654_STATUS_F2F;
 694 +
 695 +       return sprintf(buf, "%d\n",
 696 +               !!(tc->cached_regs[TC654_REG_STATUS] & fan_fault_mask));
 697 +}
 698 +
 699 +static ssize_t
 700 +show_fan_pulses(struct device *dev, struct device_attribute *da, char *buf)
 701 +{
 702 +       struct tc654 *tc = dev_get_drvdata(dev);
 703 +       int nr = to_sensor_dev_attr(da)->index;
 704 +
 705 +       return sprintf(buf, "%d\n", get_fan_pulse(tc, nr));
 706 +}
 707 +
 708 +static ssize_t
 709 +set_fan_pulses(struct device *dev, struct device_attribute *da,
 710 +             const char *buf, size_t count)
 711 +{
 712 +       struct tc654 *tc = dev_get_drvdata(dev);
 713 +       long new_pulse;
 714 +       int nr = to_sensor_dev_attr(da)->index;
 715 +       int status = kstrtol(buf, 10, &new_pulse);
 716 +
 717 +       if (status < 0)
 718 +               return status;
 719 +
 720 +       status = set_fan_pulse(tc, nr, new_pulse);
 721 +       if (status < 0)
 722 +               return status;
 723 +
 724 +       return count;
 725 +}
 726 +
 727 +static ssize_t
 728 +show_pwm_enable(struct device *dev, struct device_attribute *da, char *buf)
 729 +{
 730 +       struct tc654 *tc = tc654_update_device(dev);
 731 +       int pwm_enabled;
 732 +
 733 +       if ((tc->cached_regs[TC654_REG_CONFIG] & TC654_CTRL_SDM) &&
 734 +           !tc->pwm_manual) {
 735 +               pwm_enabled = 0; /* full off */
 736 +       } else {
 737 +               if (tc->valid && tc->vin_status == 0)
 738 +                       pwm_enabled = 2; /* automatic fan speed control */
 739 +
 740 +               pwm_enabled = 1; /* PWM Mode */
 741 +       }
 742 +
 743 +       return sprintf(buf, "%d\n", pwm_enabled);
 744 +}
 745 +
 746 +static ssize_t
 747 +set_pwm_enable(struct device *dev, struct device_attribute *da,
 748 +              const char *buf, size_t count)
 749 +{
 750 +       struct tc654 *tc = dev_get_drvdata(dev);
 751 +       long new_value;
 752 +
 753 +       int result = kstrtol(buf, 10, &new_value);
 754 +
 755 +       if (result < 0)
 756 +               return result;
 757 +
 758 +       mutex_lock(&tc->update_lock);
 759 +       switch (new_value) {
 760 +       case 0: /* no fan control (i.e. is OFF) */
 761 +               result = write_fan_mode(tc, TC654_PWM_OFF);
 762 +               tc->pwm_manual = false;
 763 +               break;
 764 +
 765 +       case 1: /* manual fan control enabled (using pwm) */
 766 +               result = write_fan_mode(tc, TC654_PWM_10000);
 767 +               break;
 768 +
 769 +       case 2: /* automatic fan speed control enabled */
 770 +               result = write_fan_mode(tc, TC654_PWM_VIN);
 771 +               break;
 772 +
 773 +       default:
 774 +               result = -EINVAL;
 775 +       }
 776 +
 777 +       mutex_unlock(&tc->update_lock);
 778 +       return result < 0 ? result : count;
 779 +}
 780 +
 781 +static ssize_t
 782 +show_pwm(struct device *dev, struct device_attribute *da, char *buf)
 783 +{
 784 +       struct tc654 *tc = tc654_update_device(dev);
 785 +       int ret;
 786 +
 787 +       ret = get_fan_speed(tc);
 788 +       if (ret < 0)
 789 +               return ret;
 790 +
 791 +       return sprintf(buf, "%d\n", ret);
 792 +}
 793 +
 794 +static ssize_t
 795 +set_pwm(struct device *dev, struct device_attribute *da,
 796 +       const char *buf, size_t count)
 797 +{
 798 +       struct tc654 *tc = dev_get_drvdata(dev);
 799 +       long new_value = -1;
 800 +       int result = kstrtol(buf, 10, &new_value);
 801 +
 802 +       if (result < 0)
 803 +               return result;
 804 +
 805 +       if (new_value < 0 || new_value > INT_MAX)
 806 +               return -EINVAL;
 807 +
 808 +       if (!tc->pwm_manual)
 809 +               return -EINVAL;
 810 +
 811 +       result = set_fan_speed(tc, new_value);
 812 +       if (result < 0)
 813 +               return result;
 814 +
 815 +       return count;
 816 +}
 817 +
 818 +static ssize_t
 819 +show_temp_alarm_otf(struct device *dev, struct device_attribute *da, char *buf)
 820 +{
 821 +       struct tc654 *tc = tc654_update_device(dev);
 822 +
 823 +       return sprintf(buf, "%d\n", tc->alarms[TC654_ALARM_OVER_TEMPERATURE]);
 824 +}
 825 +
 826 +static SENSOR_DEVICE_ATTR(fan1_input, S_IRUGO, show_fan_input,
 827 +                         NULL, TC654_FAN1);
 828 +static SENSOR_DEVICE_ATTR(fan1_min, S_IRUGO | S_IWUSR, show_fan_min,
 829 +                         set_fan_min, TC654_FAN1);
 830 +static SENSOR_DEVICE_ATTR(fan1_min_alarm, S_IRUGO, show_fan_min_alarm,
 831 +                         NULL, TC654_FAN1);
 832 +static SENSOR_DEVICE_ATTR(fan1_max_alarm, S_IRUGO, show_fan_max_alarm,
 833 +                         NULL, TC654_FAN1);
 834 +static SENSOR_DEVICE_ATTR(fan1_max, S_IRUGO, show_fan_max, NULL, TC654_FAN1);
 835 +static SENSOR_DEVICE_ATTR(fan1_fault, S_IRUGO, show_fan_fault,
 836 +                         NULL, TC654_FAN1);
 837 +static SENSOR_DEVICE_ATTR(fan1_pulses, S_IRUGO | S_IWUSR, show_fan_pulses,
 838 +                         set_fan_pulses, TC654_FAN1);
 839 +static SENSOR_DEVICE_ATTR(fan2_input, S_IRUGO, show_fan_input,
 840 +                         NULL, TC654_FAN2);
 841 +static SENSOR_DEVICE_ATTR(fan2_min, S_IRUGO | S_IWUSR, show_fan_min,
 842 +                         set_fan_min, TC654_FAN2);
 843 +static SENSOR_DEVICE_ATTR(fan2_max, S_IRUGO, show_fan_max,
 844 +                         NULL, TC654_FAN2);
 845 +static SENSOR_DEVICE_ATTR(fan2_min_alarm, S_IRUGO, show_fan_min_alarm,
 846 +                         NULL, TC654_FAN2);
 847 +static SENSOR_DEVICE_ATTR(fan2_max_alarm, S_IRUGO, show_fan_max_alarm,
 848 +                         NULL, TC654_FAN2);
 849 +static SENSOR_DEVICE_ATTR(fan2_fault, S_IRUGO, show_fan_fault,
 850 +                         NULL, TC654_FAN2);
 851 +static SENSOR_DEVICE_ATTR(fan2_pulses, S_IRUGO | S_IWUSR, show_fan_pulses,
 852 +                         set_fan_pulses, TC654_FAN2);
 853 +
 854 +static DEVICE_ATTR(pwm1_enable, S_IRUGO | S_IWUSR, show_pwm_enable,
 855 +       set_pwm_enable);
 856 +static DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, show_pwm, set_pwm);
 857 +
 858 +static DEVICE_ATTR(temp1_emergency_alarm, S_IRUGO, show_temp_alarm_otf, NULL);
 859 +
 860 +/* sensors present on all models */
 861 +static struct attribute *tc654_attrs[] = {
 862 +       &sensor_dev_attr_fan1_input.dev_attr.attr,
 863 +       &sensor_dev_attr_fan1_min.dev_attr.attr,
 864 +       &sensor_dev_attr_fan1_max.dev_attr.attr,
 865 +       &sensor_dev_attr_fan1_min_alarm.dev_attr.attr,
 866 +       &sensor_dev_attr_fan1_max_alarm.dev_attr.attr,
 867 +       &sensor_dev_attr_fan1_fault.dev_attr.attr,
 868 +       &sensor_dev_attr_fan1_pulses.dev_attr.attr,
 869 +       &sensor_dev_attr_fan2_input.dev_attr.attr,
 870 +       &sensor_dev_attr_fan2_min.dev_attr.attr,
 871 +       &sensor_dev_attr_fan2_max.dev_attr.attr,
 872 +       &sensor_dev_attr_fan2_min_alarm.dev_attr.attr,
 873 +       &sensor_dev_attr_fan2_max_alarm.dev_attr.attr,
 874 +       &sensor_dev_attr_fan2_fault.dev_attr.attr,
 875 +       &sensor_dev_attr_fan2_pulses.dev_attr.attr,
 876 +
 877 +       &dev_attr_pwm1_enable.attr,
 878 +       &dev_attr_pwm1.attr,
 879 +
 880 +       &dev_attr_temp1_emergency_alarm.attr,
 881 +       NULL
 882 +};
 883 +
 884 +ATTRIBUTE_GROUPS(tc654);
 885 +
 886 +/* cooling device */
 887 +
 888 +static int tc654_get_max_state(struct thermal_cooling_device *cdev,
 889 +                              unsigned long *state)
 890 +{
 891 +       *state = 255;
 892 +       return 0;
 893 +}
 894 +
 895 +static int tc654_get_cur_state(struct thermal_cooling_device *cdev,
 896 +                              unsigned long *state)
 897 +{
 898 +       struct tc654 *tc = cdev->devdata;
 899 +       int ret;
 900 +
 901 +       if (!tc)
 902 +               return -EINVAL;
 903 +
 904 +       ret = get_fan_speed(tc);
 905 +       if (ret < 0)
 906 +               return ret;
 907 +
 908 +       *state = ret;
 909 +       return 0;
 910 +}
 911 +
 912 +static int tc654_set_cur_state(struct thermal_cooling_device *cdev,
 913 +                              unsigned long state)
 914 +{
 915 +       struct tc654 *tc = cdev->devdata;
 916 +
 917 +       if (!tc)
 918 +               return -EINVAL;
 919 +
 920 +       if (state > INT_MAX)
 921 +               return -EINVAL;
 922 +
 923 +       return set_fan_speed(tc, state);
 924 +}
 925 +
 926 +static const struct thermal_cooling_device_ops tc654_fan_cool_ops = {
 927 +       .get_max_state = tc654_get_max_state,
 928 +       .get_cur_state = tc654_get_cur_state,
 929 +       .set_cur_state = tc654_set_cur_state,
 930 +};
 931 +
 932 +
 933 +/* hardware probe and detection */
 934 +
 935 +static int
 936 +tc654_probe(struct i2c_client *client, const struct i2c_device_id *id)
 937 +{
 938 +       struct tc654 *tc;
 939 +       struct device *hwmon_dev;
 940 +       int ret, i;
 941 +
 942 +       if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 943 +               return -EIO;
 944 +
 945 +       tc = devm_kzalloc(&client->dev, sizeof(*tc), GFP_KERNEL);
 946 +       if (!tc)
 947 +               return -ENOMEM;
 948 +
 949 +       i2c_set_clientdata(client, tc);
 950 +       tc->client = client;
 951 +       mutex_init(&tc->update_lock);
 952 +
 953 +       /* cache all 8 registers */
 954 +       for (i = 0; i < __TC654_REG_NUM; i++) {
 955 +               ret = read_tc(tc, i);
 956 +               if (ret < 0)
 957 +                       return ret;
 958 +       }
 959 +
 960 +       /* sysfs hooks */
 961 +       hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
 962 +                                                          client->name, tc,
 963 +                                                          tc654_groups);
 964 +       if (IS_ERR(hwmon_dev))
 965 +               return PTR_ERR(hwmon_dev);
 966 +
 967 +#if IS_ENABLED(CONFIG_OF)
 968 +       /* Optional cooling device register for Device tree platforms */
 969 +       tc->cdev = thermal_of_cooling_device_register(client->dev.of_node,
 970 +                                                     "tc654", tc,
 971 +                                                     &tc654_fan_cool_ops);
 972 +#else /* CONFIG_OF */
 973 +       /* Optional cooling device register for non Device tree platforms */
 974 +       tc->cdev = thermal_cooling_device_register("tc654", tc,
 975 +                                                  &tc654_fan_cool_ops);
 976 +#endif /* CONFIG_OF */
 977 +
 978 +       dev_info(&client->dev, "%s: sensor '%s'\n",
 979 +                dev_name(hwmon_dev), client->name);
 980 +
 981 +       return 0;
 982 +}
 983 +
 984 +static const struct i2c_device_id tc654_ids[] = {
 985 +       { "tc654", 0, },
 986 +       { }
 987 +};
 988 +MODULE_DEVICE_TABLE(i2c, tc654_ids);
 989 +
 990 +/* Return 0 if detection is successful, -ENODEV otherwise */
 991 +static int
 992 +tc654_detect(struct i2c_client *new_client, struct i2c_board_info *info)
 993 +{
 994 +       struct i2c_adapter *adapter = new_client->adapter;
 995 +       int manufacturer, product;
 996 +
 997 +       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 998 +               return -ENODEV;
 999 +
1000 +       manufacturer = i2c_smbus_read_byte_data(new_client, TC654_REG_MFR_ID);
1001 +       if (manufacturer != TC654_MFR_ID_MICROCHIP)
1002 +               return -ENODEV;
1003 +
1004 +       product = i2c_smbus_read_byte_data(new_client, TC654_REG_VER_ID);
1005 +       if (!((product == TC654_VER_ID) || (product == TC655_VER_ID)))
1006 +               return -ENODEV;
1007 +
1008 +       strlcpy(info->type, "tc654", I2C_NAME_SIZE);
1009 +       return 0;
1010 +}
1011 +
1012 +static struct i2c_driver tc654_driver = {
1013 +       .class          = I2C_CLASS_HWMON,
1014 +       .driver = {
1015 +               .name   = "tc654",
1016 +       },
1017 +       .probe          = tc654_probe,
1018 +       .id_table       = tc654_ids,
1019 +       .detect         = tc654_detect,
1020 +       .address_list   = normal_i2c,
1021 +};
1022 +
1023 +module_i2c_driver(tc654_driver);
1024 +
1025 +MODULE_AUTHOR("Christian Lamparter <chunkeey@gmail.com>");
1026 +MODULE_DESCRIPTION("Microchip TC654/TC655 hwmon driver");
1027 +MODULE_LICENSE("GPL");