linux/drivers/hwmon/emc2103.c
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   1/*
   2 * emc2103.c - Support for SMSC EMC2103
   3 * Copyright (c) 2010 SMSC
   4 *
   5 * This program is free software; you can redistribute it and/or modify
   6 * it under the terms of the GNU General Public License as published by
   7 * the Free Software Foundation; either version 2 of the License, or
   8 * (at your option) any later version.
   9 *
  10 * This program is distributed in the hope that it will be useful,
  11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 * GNU General Public License for more details.
  14 *
  15 * You should have received a copy of the GNU General Public License
  16 * along with this program; if not, write to the Free Software
  17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 */
  19
  20#include <linux/module.h>
  21#include <linux/init.h>
  22#include <linux/slab.h>
  23#include <linux/jiffies.h>
  24#include <linux/i2c.h>
  25#include <linux/hwmon.h>
  26#include <linux/hwmon-sysfs.h>
  27#include <linux/err.h>
  28#include <linux/mutex.h>
  29
  30/* Addresses scanned */
  31static const unsigned short normal_i2c[] = { 0x2E, I2C_CLIENT_END };
  32
  33static const u8 REG_TEMP[4] = { 0x00, 0x02, 0x04, 0x06 };
  34static const u8 REG_TEMP_MIN[4] = { 0x3c, 0x38, 0x39, 0x3a };
  35static const u8 REG_TEMP_MAX[4] = { 0x34, 0x30, 0x31, 0x32 };
  36
  37#define REG_CONF1               0x20
  38#define REG_TEMP_MAX_ALARM      0x24
  39#define REG_TEMP_MIN_ALARM      0x25
  40#define REG_FAN_CONF1           0x42
  41#define REG_FAN_TARGET_LO       0x4c
  42#define REG_FAN_TARGET_HI       0x4d
  43#define REG_FAN_TACH_HI         0x4e
  44#define REG_FAN_TACH_LO         0x4f
  45#define REG_PRODUCT_ID          0xfd
  46#define REG_MFG_ID              0xfe
  47
  48/* equation 4 from datasheet: rpm = (3932160 * multipler) / count */
  49#define FAN_RPM_FACTOR          3932160
  50
  51/*
  52 * 2103-2 and 2103-4's 3rd temperature sensor can be connected to two diodes
  53 * in anti-parallel mode, and in this configuration both can be read
  54 * independently (so we have 4 temperature inputs).  The device can't
  55 * detect if it's connected in this mode, so we have to manually enable
  56 * it.  Default is to leave the device in the state it's already in (-1).
  57 * This parameter allows APD mode to be optionally forced on or off
  58 */
  59static int apd = -1;
  60module_param(apd, bint, 0);
  61MODULE_PARM_DESC(apd, "Set to zero to disable anti-parallel diode mode");
  62
  63struct temperature {
  64        s8      degrees;
  65        u8      fraction;       /* 0-7 multiples of 0.125 */
  66};
  67
  68struct emc2103_data {
  69        struct i2c_client       *client;
  70        const struct            attribute_group *groups[4];
  71        struct mutex            update_lock;
  72        bool                    valid;          /* registers are valid */
  73        bool                    fan_rpm_control;
  74        int                     temp_count;     /* num of temp sensors */
  75        unsigned long           last_updated;   /* in jiffies */
  76        struct temperature      temp[4];        /* internal + 3 external */
  77        s8                      temp_min[4];    /* no fractional part */
  78        s8                      temp_max[4];    /* no fractional part */
  79        u8                      temp_min_alarm;
  80        u8                      temp_max_alarm;
  81        u8                      fan_multiplier;
  82        u16                     fan_tach;
  83        u16                     fan_target;
  84};
  85
  86static int read_u8_from_i2c(struct i2c_client *client, u8 i2c_reg, u8 *output)
  87{
  88        int status = i2c_smbus_read_byte_data(client, i2c_reg);
  89        if (status < 0) {
  90                dev_warn(&client->dev, "reg 0x%02x, err %d\n",
  91                        i2c_reg, status);
  92        } else {
  93                *output = status;
  94        }
  95        return status;
  96}
  97
  98static void read_temp_from_i2c(struct i2c_client *client, u8 i2c_reg,
  99                               struct temperature *temp)
 100{
 101        u8 degrees, fractional;
 102
 103        if (read_u8_from_i2c(client, i2c_reg, &degrees) < 0)
 104                return;
 105
 106        if (read_u8_from_i2c(client, i2c_reg + 1, &fractional) < 0)
 107                return;
 108
 109        temp->degrees = degrees;
 110        temp->fraction = (fractional & 0xe0) >> 5;
 111}
 112
 113static void read_fan_from_i2c(struct i2c_client *client, u16 *output,
 114                              u8 hi_addr, u8 lo_addr)
 115{
 116        u8 high_byte, lo_byte;
 117
 118        if (read_u8_from_i2c(client, hi_addr, &high_byte) < 0)
 119                return;
 120
 121        if (read_u8_from_i2c(client, lo_addr, &lo_byte) < 0)
 122                return;
 123
 124        *output = ((u16)high_byte << 5) | (lo_byte >> 3);
 125}
 126
 127static void write_fan_target_to_i2c(struct i2c_client *client, u16 new_target)
 128{
 129        u8 high_byte = (new_target & 0x1fe0) >> 5;
 130        u8 low_byte = (new_target & 0x001f) << 3;
 131        i2c_smbus_write_byte_data(client, REG_FAN_TARGET_LO, low_byte);
 132        i2c_smbus_write_byte_data(client, REG_FAN_TARGET_HI, high_byte);
 133}
 134
 135static void read_fan_config_from_i2c(struct i2c_client *client)
 136
 137{
 138        struct emc2103_data *data = i2c_get_clientdata(client);
 139        u8 conf1;
 140
 141        if (read_u8_from_i2c(client, REG_FAN_CONF1, &conf1) < 0)
 142                return;
 143
 144        data->fan_multiplier = 1 << ((conf1 & 0x60) >> 5);
 145        data->fan_rpm_control = (conf1 & 0x80) != 0;
 146}
 147
 148static struct emc2103_data *emc2103_update_device(struct device *dev)
 149{
 150        struct emc2103_data *data = dev_get_drvdata(dev);
 151        struct i2c_client *client = data->client;
 152
 153        mutex_lock(&data->update_lock);
 154
 155        if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
 156            || !data->valid) {
 157                int i;
 158
 159                for (i = 0; i < data->temp_count; i++) {
 160                        read_temp_from_i2c(client, REG_TEMP[i], &data->temp[i]);
 161                        read_u8_from_i2c(client, REG_TEMP_MIN[i],
 162                                &data->temp_min[i]);
 163                        read_u8_from_i2c(client, REG_TEMP_MAX[i],
 164                                &data->temp_max[i]);
 165                }
 166
 167                read_u8_from_i2c(client, REG_TEMP_MIN_ALARM,
 168                        &data->temp_min_alarm);
 169                read_u8_from_i2c(client, REG_TEMP_MAX_ALARM,
 170                        &data->temp_max_alarm);
 171
 172                read_fan_from_i2c(client, &data->fan_tach,
 173                        REG_FAN_TACH_HI, REG_FAN_TACH_LO);
 174                read_fan_from_i2c(client, &data->fan_target,
 175                        REG_FAN_TARGET_HI, REG_FAN_TARGET_LO);
 176                read_fan_config_from_i2c(client);
 177
 178                data->last_updated = jiffies;
 179                data->valid = true;
 180        }
 181
 182        mutex_unlock(&data->update_lock);
 183
 184        return data;
 185}
 186
 187static ssize_t
 188show_temp(struct device *dev, struct device_attribute *da, char *buf)
 189{
 190        int nr = to_sensor_dev_attr(da)->index;
 191        struct emc2103_data *data = emc2103_update_device(dev);
 192        int millidegrees = data->temp[nr].degrees * 1000
 193                + data->temp[nr].fraction * 125;
 194        return sprintf(buf, "%d\n", millidegrees);
 195}
 196
 197static ssize_t
 198show_temp_min(struct device *dev, struct device_attribute *da, char *buf)
 199{
 200        int nr = to_sensor_dev_attr(da)->index;
 201        struct emc2103_data *data = emc2103_update_device(dev);
 202        int millidegrees = data->temp_min[nr] * 1000;
 203        return sprintf(buf, "%d\n", millidegrees);
 204}
 205
 206static ssize_t
 207show_temp_max(struct device *dev, struct device_attribute *da, char *buf)
 208{
 209        int nr = to_sensor_dev_attr(da)->index;
 210        struct emc2103_data *data = emc2103_update_device(dev);
 211        int millidegrees = data->temp_max[nr] * 1000;
 212        return sprintf(buf, "%d\n", millidegrees);
 213}
 214
 215static ssize_t
 216show_temp_fault(struct device *dev, struct device_attribute *da, char *buf)
 217{
 218        int nr = to_sensor_dev_attr(da)->index;
 219        struct emc2103_data *data = emc2103_update_device(dev);
 220        bool fault = (data->temp[nr].degrees == -128);
 221        return sprintf(buf, "%d\n", fault ? 1 : 0);
 222}
 223
 224static ssize_t
 225show_temp_min_alarm(struct device *dev, struct device_attribute *da, char *buf)
 226{
 227        int nr = to_sensor_dev_attr(da)->index;
 228        struct emc2103_data *data = emc2103_update_device(dev);
 229        bool alarm = data->temp_min_alarm & (1 << nr);
 230        return sprintf(buf, "%d\n", alarm ? 1 : 0);
 231}
 232
 233static ssize_t
 234show_temp_max_alarm(struct device *dev, struct device_attribute *da, char *buf)
 235{
 236        int nr = to_sensor_dev_attr(da)->index;
 237        struct emc2103_data *data = emc2103_update_device(dev);
 238        bool alarm = data->temp_max_alarm & (1 << nr);
 239        return sprintf(buf, "%d\n", alarm ? 1 : 0);
 240}
 241
 242static ssize_t set_temp_min(struct device *dev, struct device_attribute *da,
 243                            const char *buf, size_t count)
 244{
 245        int nr = to_sensor_dev_attr(da)->index;
 246        struct emc2103_data *data = dev_get_drvdata(dev);
 247        struct i2c_client *client = data->client;
 248        long val;
 249
 250        int result = kstrtol(buf, 10, &val);
 251        if (result < 0)
 252                return result;
 253
 254        val = DIV_ROUND_CLOSEST(clamp_val(val, -63000, 127000), 1000);
 255
 256        mutex_lock(&data->update_lock);
 257        data->temp_min[nr] = val;
 258        i2c_smbus_write_byte_data(client, REG_TEMP_MIN[nr], val);
 259        mutex_unlock(&data->update_lock);
 260
 261        return count;
 262}
 263
 264static ssize_t set_temp_max(struct device *dev, struct device_attribute *da,
 265                            const char *buf, size_t count)
 266{
 267        int nr = to_sensor_dev_attr(da)->index;
 268        struct emc2103_data *data = dev_get_drvdata(dev);
 269        struct i2c_client *client = data->client;
 270        long val;
 271
 272        int result = kstrtol(buf, 10, &val);
 273        if (result < 0)
 274                return result;
 275
 276        val = DIV_ROUND_CLOSEST(clamp_val(val, -63000, 127000), 1000);
 277
 278        mutex_lock(&data->update_lock);
 279        data->temp_max[nr] = val;
 280        i2c_smbus_write_byte_data(client, REG_TEMP_MAX[nr], val);
 281        mutex_unlock(&data->update_lock);
 282
 283        return count;
 284}
 285
 286static ssize_t
 287fan1_input_show(struct device *dev, struct device_attribute *da, char *buf)
 288{
 289        struct emc2103_data *data = emc2103_update_device(dev);
 290        int rpm = 0;
 291        if (data->fan_tach != 0)
 292                rpm = (FAN_RPM_FACTOR * data->fan_multiplier) / data->fan_tach;
 293        return sprintf(buf, "%d\n", rpm);
 294}
 295
 296static ssize_t
 297fan1_div_show(struct device *dev, struct device_attribute *da, char *buf)
 298{
 299        struct emc2103_data *data = emc2103_update_device(dev);
 300        int fan_div = 8 / data->fan_multiplier;
 301        return sprintf(buf, "%d\n", fan_div);
 302}
 303
 304/*
 305 * Note: we also update the fan target here, because its value is
 306 * determined in part by the fan clock divider.  This follows the principle
 307 * of least surprise; the user doesn't expect the fan target to change just
 308 * because the divider changed.
 309 */
 310static ssize_t fan1_div_store(struct device *dev, struct device_attribute *da,
 311                              const char *buf, size_t count)
 312{
 313        struct emc2103_data *data = emc2103_update_device(dev);
 314        struct i2c_client *client = data->client;
 315        int new_range_bits, old_div = 8 / data->fan_multiplier;
 316        long new_div;
 317
 318        int status = kstrtol(buf, 10, &new_div);
 319        if (status < 0)
 320                return status;
 321
 322        if (new_div == old_div) /* No change */
 323                return count;
 324
 325        switch (new_div) {
 326        case 1:
 327                new_range_bits = 3;
 328                break;
 329        case 2:
 330                new_range_bits = 2;
 331                break;
 332        case 4:
 333                new_range_bits = 1;
 334                break;
 335        case 8:
 336                new_range_bits = 0;
 337                break;
 338        default:
 339                return -EINVAL;
 340        }
 341
 342        mutex_lock(&data->update_lock);
 343
 344        status = i2c_smbus_read_byte_data(client, REG_FAN_CONF1);
 345        if (status < 0) {
 346                dev_dbg(&client->dev, "reg 0x%02x, err %d\n",
 347                        REG_FAN_CONF1, status);
 348                mutex_unlock(&data->update_lock);
 349                return status;
 350        }
 351        status &= 0x9F;
 352        status |= (new_range_bits << 5);
 353        i2c_smbus_write_byte_data(client, REG_FAN_CONF1, status);
 354
 355        data->fan_multiplier = 8 / new_div;
 356
 357        /* update fan target if high byte is not disabled */
 358        if ((data->fan_target & 0x1fe0) != 0x1fe0) {
 359                u16 new_target = (data->fan_target * old_div) / new_div;
 360                data->fan_target = min(new_target, (u16)0x1fff);
 361                write_fan_target_to_i2c(client, data->fan_target);
 362        }
 363
 364        /* invalidate data to force re-read from hardware */
 365        data->valid = false;
 366
 367        mutex_unlock(&data->update_lock);
 368        return count;
 369}
 370
 371static ssize_t
 372fan1_target_show(struct device *dev, struct device_attribute *da, char *buf)
 373{
 374        struct emc2103_data *data = emc2103_update_device(dev);
 375        int rpm = 0;
 376
 377        /* high byte of 0xff indicates disabled so return 0 */
 378        if ((data->fan_target != 0) && ((data->fan_target & 0x1fe0) != 0x1fe0))
 379                rpm = (FAN_RPM_FACTOR * data->fan_multiplier)
 380                        / data->fan_target;
 381
 382        return sprintf(buf, "%d\n", rpm);
 383}
 384
 385static ssize_t fan1_target_store(struct device *dev,
 386                                 struct device_attribute *da, const char *buf,
 387                                 size_t count)
 388{
 389        struct emc2103_data *data = emc2103_update_device(dev);
 390        struct i2c_client *client = data->client;
 391        unsigned long rpm_target;
 392
 393        int result = kstrtoul(buf, 10, &rpm_target);
 394        if (result < 0)
 395                return result;
 396
 397        /* Datasheet states 16384 as maximum RPM target (table 3.2) */
 398        rpm_target = clamp_val(rpm_target, 0, 16384);
 399
 400        mutex_lock(&data->update_lock);
 401
 402        if (rpm_target == 0)
 403                data->fan_target = 0x1fff;
 404        else
 405                data->fan_target = clamp_val(
 406                        (FAN_RPM_FACTOR * data->fan_multiplier) / rpm_target,
 407                        0, 0x1fff);
 408
 409        write_fan_target_to_i2c(client, data->fan_target);
 410
 411        mutex_unlock(&data->update_lock);
 412        return count;
 413}
 414
 415static ssize_t
 416fan1_fault_show(struct device *dev, struct device_attribute *da, char *buf)
 417{
 418        struct emc2103_data *data = emc2103_update_device(dev);
 419        bool fault = ((data->fan_tach & 0x1fe0) == 0x1fe0);
 420        return sprintf(buf, "%d\n", fault ? 1 : 0);
 421}
 422
 423static ssize_t
 424pwm1_enable_show(struct device *dev, struct device_attribute *da, char *buf)
 425{
 426        struct emc2103_data *data = emc2103_update_device(dev);
 427        return sprintf(buf, "%d\n", data->fan_rpm_control ? 3 : 0);
 428}
 429
 430static ssize_t pwm1_enable_store(struct device *dev,
 431                                 struct device_attribute *da, const char *buf,
 432                                 size_t count)
 433{
 434        struct emc2103_data *data = dev_get_drvdata(dev);
 435        struct i2c_client *client = data->client;
 436        long new_value;
 437        u8 conf_reg;
 438
 439        int result = kstrtol(buf, 10, &new_value);
 440        if (result < 0)
 441                return result;
 442
 443        mutex_lock(&data->update_lock);
 444        switch (new_value) {
 445        case 0:
 446                data->fan_rpm_control = false;
 447                break;
 448        case 3:
 449                data->fan_rpm_control = true;
 450                break;
 451        default:
 452                count = -EINVAL;
 453                goto err;
 454        }
 455
 456        result = read_u8_from_i2c(client, REG_FAN_CONF1, &conf_reg);
 457        if (result) {
 458                count = result;
 459                goto err;
 460        }
 461
 462        if (data->fan_rpm_control)
 463                conf_reg |= 0x80;
 464        else
 465                conf_reg &= ~0x80;
 466
 467        i2c_smbus_write_byte_data(client, REG_FAN_CONF1, conf_reg);
 468err:
 469        mutex_unlock(&data->update_lock);
 470        return count;
 471}
 472
 473static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL, 0);
 474static SENSOR_DEVICE_ATTR(temp1_min, S_IRUGO | S_IWUSR, show_temp_min,
 475        set_temp_min, 0);
 476static SENSOR_DEVICE_ATTR(temp1_max, S_IRUGO | S_IWUSR, show_temp_max,
 477        set_temp_max, 0);
 478static SENSOR_DEVICE_ATTR(temp1_fault, S_IRUGO, show_temp_fault, NULL, 0);
 479static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, show_temp_min_alarm,
 480        NULL, 0);
 481static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, show_temp_max_alarm,
 482        NULL, 0);
 483
 484static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_temp, NULL, 1);
 485static SENSOR_DEVICE_ATTR(temp2_min, S_IRUGO | S_IWUSR, show_temp_min,
 486        set_temp_min, 1);
 487static SENSOR_DEVICE_ATTR(temp2_max, S_IRUGO | S_IWUSR, show_temp_max,
 488        set_temp_max, 1);
 489static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_temp_fault, NULL, 1);
 490static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_temp_min_alarm,
 491        NULL, 1);
 492static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_temp_max_alarm,
 493        NULL, 1);
 494
 495static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, show_temp, NULL, 2);
 496static SENSOR_DEVICE_ATTR(temp3_min, S_IRUGO | S_IWUSR, show_temp_min,
 497        set_temp_min, 2);
 498static SENSOR_DEVICE_ATTR(temp3_max, S_IRUGO | S_IWUSR, show_temp_max,
 499        set_temp_max, 2);
 500static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_temp_fault, NULL, 2);
 501static SENSOR_DEVICE_ATTR(temp3_min_alarm, S_IRUGO, show_temp_min_alarm,
 502        NULL, 2);
 503static SENSOR_DEVICE_ATTR(temp3_max_alarm, S_IRUGO, show_temp_max_alarm,
 504        NULL, 2);
 505
 506static SENSOR_DEVICE_ATTR(temp4_input, S_IRUGO, show_temp, NULL, 3);
 507static SENSOR_DEVICE_ATTR(temp4_min, S_IRUGO | S_IWUSR, show_temp_min,
 508        set_temp_min, 3);
 509static SENSOR_DEVICE_ATTR(temp4_max, S_IRUGO | S_IWUSR, show_temp_max,
 510        set_temp_max, 3);
 511static SENSOR_DEVICE_ATTR(temp4_fault, S_IRUGO, show_temp_fault, NULL, 3);
 512static SENSOR_DEVICE_ATTR(temp4_min_alarm, S_IRUGO, show_temp_min_alarm,
 513        NULL, 3);
 514static SENSOR_DEVICE_ATTR(temp4_max_alarm, S_IRUGO, show_temp_max_alarm,
 515        NULL, 3);
 516
 517static DEVICE_ATTR_RO(fan1_input);
 518static DEVICE_ATTR_RW(fan1_div);
 519static DEVICE_ATTR_RW(fan1_target);
 520static DEVICE_ATTR_RO(fan1_fault);
 521
 522static DEVICE_ATTR_RW(pwm1_enable);
 523
 524/* sensors present on all models */
 525static struct attribute *emc2103_attributes[] = {
 526        &sensor_dev_attr_temp1_input.dev_attr.attr,
 527        &sensor_dev_attr_temp1_min.dev_attr.attr,
 528        &sensor_dev_attr_temp1_max.dev_attr.attr,
 529        &sensor_dev_attr_temp1_fault.dev_attr.attr,
 530        &sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
 531        &sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
 532        &sensor_dev_attr_temp2_input.dev_attr.attr,
 533        &sensor_dev_attr_temp2_min.dev_attr.attr,
 534        &sensor_dev_attr_temp2_max.dev_attr.attr,
 535        &sensor_dev_attr_temp2_fault.dev_attr.attr,
 536        &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 537        &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 538        &dev_attr_fan1_input.attr,
 539        &dev_attr_fan1_div.attr,
 540        &dev_attr_fan1_target.attr,
 541        &dev_attr_fan1_fault.attr,
 542        &dev_attr_pwm1_enable.attr,
 543        NULL
 544};
 545
 546/* extra temperature sensors only present on 2103-2 and 2103-4 */
 547static struct attribute *emc2103_attributes_temp3[] = {
 548        &sensor_dev_attr_temp3_input.dev_attr.attr,
 549        &sensor_dev_attr_temp3_min.dev_attr.attr,
 550        &sensor_dev_attr_temp3_max.dev_attr.attr,
 551        &sensor_dev_attr_temp3_fault.dev_attr.attr,
 552        &sensor_dev_attr_temp3_min_alarm.dev_attr.attr,
 553        &sensor_dev_attr_temp3_max_alarm.dev_attr.attr,
 554        NULL
 555};
 556
 557/* extra temperature sensors only present on 2103-2 and 2103-4 in APD mode */
 558static struct attribute *emc2103_attributes_temp4[] = {
 559        &sensor_dev_attr_temp4_input.dev_attr.attr,
 560        &sensor_dev_attr_temp4_min.dev_attr.attr,
 561        &sensor_dev_attr_temp4_max.dev_attr.attr,
 562        &sensor_dev_attr_temp4_fault.dev_attr.attr,
 563        &sensor_dev_attr_temp4_min_alarm.dev_attr.attr,
 564        &sensor_dev_attr_temp4_max_alarm.dev_attr.attr,
 565        NULL
 566};
 567
 568static const struct attribute_group emc2103_group = {
 569        .attrs = emc2103_attributes,
 570};
 571
 572static const struct attribute_group emc2103_temp3_group = {
 573        .attrs = emc2103_attributes_temp3,
 574};
 575
 576static const struct attribute_group emc2103_temp4_group = {
 577        .attrs = emc2103_attributes_temp4,
 578};
 579
 580static int
 581emc2103_probe(struct i2c_client *client, const struct i2c_device_id *id)
 582{
 583        struct emc2103_data *data;
 584        struct device *hwmon_dev;
 585        int status, idx = 0;
 586
 587        if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 588                return -EIO;
 589
 590        data = devm_kzalloc(&client->dev, sizeof(struct emc2103_data),
 591                            GFP_KERNEL);
 592        if (!data)
 593                return -ENOMEM;
 594
 595        i2c_set_clientdata(client, data);
 596        data->client = client;
 597        mutex_init(&data->update_lock);
 598
 599        /* 2103-2 and 2103-4 have 3 external diodes, 2103-1 has 1 */
 600        status = i2c_smbus_read_byte_data(client, REG_PRODUCT_ID);
 601        if (status == 0x24) {
 602                /* 2103-1 only has 1 external diode */
 603                data->temp_count = 2;
 604        } else {
 605                /* 2103-2 and 2103-4 have 3 or 4 external diodes */
 606                status = i2c_smbus_read_byte_data(client, REG_CONF1);
 607                if (status < 0) {
 608                        dev_dbg(&client->dev, "reg 0x%02x, err %d\n", REG_CONF1,
 609                                status);
 610                        return status;
 611                }
 612
 613                /* detect current state of hardware */
 614                data->temp_count = (status & 0x01) ? 4 : 3;
 615
 616                /* force APD state if module parameter is set */
 617                if (apd == 0) {
 618                        /* force APD mode off */
 619                        data->temp_count = 3;
 620                        status &= ~(0x01);
 621                        i2c_smbus_write_byte_data(client, REG_CONF1, status);
 622                } else if (apd == 1) {
 623                        /* force APD mode on */
 624                        data->temp_count = 4;
 625                        status |= 0x01;
 626                        i2c_smbus_write_byte_data(client, REG_CONF1, status);
 627                }
 628        }
 629
 630        /* sysfs hooks */
 631        data->groups[idx++] = &emc2103_group;
 632        if (data->temp_count >= 3)
 633                data->groups[idx++] = &emc2103_temp3_group;
 634        if (data->temp_count == 4)
 635                data->groups[idx++] = &emc2103_temp4_group;
 636
 637        hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
 638                                                           client->name, data,
 639                                                           data->groups);
 640        if (IS_ERR(hwmon_dev))
 641                return PTR_ERR(hwmon_dev);
 642
 643        dev_info(&client->dev, "%s: sensor '%s'\n",
 644                 dev_name(hwmon_dev), client->name);
 645
 646        return 0;
 647}
 648
 649static const struct i2c_device_id emc2103_ids[] = {
 650        { "emc2103", 0, },
 651        { /* LIST END */ }
 652};
 653MODULE_DEVICE_TABLE(i2c, emc2103_ids);
 654
 655/* Return 0 if detection is successful, -ENODEV otherwise */
 656static int
 657emc2103_detect(struct i2c_client *new_client, struct i2c_board_info *info)
 658{
 659        struct i2c_adapter *adapter = new_client->adapter;
 660        int manufacturer, product;
 661
 662        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 663                return -ENODEV;
 664
 665        manufacturer = i2c_smbus_read_byte_data(new_client, REG_MFG_ID);
 666        if (manufacturer != 0x5D)
 667                return -ENODEV;
 668
 669        product = i2c_smbus_read_byte_data(new_client, REG_PRODUCT_ID);
 670        if ((product != 0x24) && (product != 0x26))
 671                return -ENODEV;
 672
 673        strlcpy(info->type, "emc2103", I2C_NAME_SIZE);
 674
 675        return 0;
 676}
 677
 678static struct i2c_driver emc2103_driver = {
 679        .class          = I2C_CLASS_HWMON,
 680        .driver = {
 681                .name   = "emc2103",
 682        },
 683        .probe          = emc2103_probe,
 684        .id_table       = emc2103_ids,
 685        .detect         = emc2103_detect,
 686        .address_list   = normal_i2c,
 687};
 688
 689module_i2c_driver(emc2103_driver);
 690
 691MODULE_AUTHOR("Steve Glendinning <steve.glendinning@shawell.net>");
 692MODULE_DESCRIPTION("SMSC EMC2103 hwmon driver");
 693MODULE_LICENSE("GPL");
 694