linux-imx

/*

 * nct7802 - Driver for Nuvoton NCT7802Y

 *

 * Copyright (C) 2014  Guenter Roeck <linux@roeck-us.net>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/err.h>

#include <linux/i2c.h>

#include <linux/init.h>

#include <linux/hwmon.h>

#include <linux/hwmon-sysfs.h>

#include <linux/jiffies.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/regmap.h>

#include <linux/slab.h>

​

#define DRVNAME "nct7802"

​

static const u8 REG_VOLTAGE[5] = { 0x09, 0x0a, 0x0c, 0x0d, 0x0e };

​

static const u8 REG_VOLTAGE_LIMIT_LSB[2][5] = {

    { 0x40, 0x00, 0x42, 0x44, 0x46 },

    { 0x3f, 0x00, 0x41, 0x43, 0x45 },

};

​

static const u8 REG_VOLTAGE_LIMIT_MSB[5] = { 0x48, 0x00, 0x47, 0x47, 0x48 };

​

static const u8 REG_VOLTAGE_LIMIT_MSB_SHIFT[2][5] = {

    { 0, 0, 4, 0, 4 },

    { 2, 0, 6, 2, 6 },

};

​

#define REG_BANK        0x00

#define REG_TEMP_LSB        0x05

#define REG_TEMP_PECI_LSB   0x08

#define REG_VOLTAGE_LOW     0x0f

#define REG_FANCOUNT_LOW    0x13

#define REG_START       0x21

#define REG_MODE        0x22 /* 7.2.32 Mode Selection Register */

#define REG_PECI_ENABLE     0x23

#define REG_FAN_ENABLE      0x24

#define REG_VMON_ENABLE     0x25

#define REG_PWM(x)      (0x60 + (x))

#define REG_SMARTFAN_EN(x)      (0x64 + (x) / 2)

#define SMARTFAN_EN_SHIFT(x)    ((x) % 2 * 4)

#define REG_VENDOR_ID       0xfd

#define REG_CHIP_ID     0xfe

#define REG_VERSION_ID      0xff

​

/*

 * Data structures and manipulation thereof

 */

​

struct nct7802_data {

    struct regmap *regmap;

    struct mutex access_lock; /* for multi-byte read and write operations */

};

​

static ssize_t temp_type_show(struct device *dev,

                  struct device_attribute *attr, char *buf)

{

    struct nct7802_data *data = dev_get_drvdata(dev);

    struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);

    unsigned int mode;

    int ret;

​

    ret = regmap_read(data->regmap, REG_MODE, &mode);

    if (ret < 0)

        return ret;

​

    return sprintf(buf, "%u\n", (mode >> (2 * sattr->index) & 3) + 2);

}

​

static ssize_t temp_type_store(struct device *dev,

                   struct device_attribute *attr, const char *buf,

                   size_t count)

{

    struct nct7802_data *data = dev_get_drvdata(dev);

    struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);