linux-imx

// SPDX-License-Identifier: GPL-2.0-or-later

/*

 * emc6w201.c - Hardware monitoring driver for the SMSC EMC6W201

 * Copyright (C) 2011  Jean Delvare <jdelvare@suse.de>

 */

​

#include <linux/module.h>

#include <linux/init.h>

#include <linux/slab.h>

#include <linux/jiffies.h>

#include <linux/i2c.h>

#include <linux/hwmon.h>

#include <linux/hwmon-sysfs.h>

#include <linux/err.h>

#include <linux/mutex.h>

​

/*

 * Addresses to scan

 */

​

static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };

​

/*

 * The EMC6W201 registers

 */

​

#define EMC6W201_REG_IN(nr)     (0x20 + (nr))

#define EMC6W201_REG_TEMP(nr)       (0x26 + (nr))

#define EMC6W201_REG_FAN(nr)        (0x2C + (nr) * 2)

#define EMC6W201_REG_COMPANY        0x3E

#define EMC6W201_REG_VERSTEP        0x3F

#define EMC6W201_REG_CONFIG     0x40

#define EMC6W201_REG_IN_LOW(nr)     (0x4A + (nr) * 2)

#define EMC6W201_REG_IN_HIGH(nr)    (0x4B + (nr) * 2)

#define EMC6W201_REG_TEMP_LOW(nr)   (0x56 + (nr) * 2)

#define EMC6W201_REG_TEMP_HIGH(nr)  (0x57 + (nr) * 2)

#define EMC6W201_REG_FAN_MIN(nr)    (0x62 + (nr) * 2)

​

enum subfeature { input, min, max };

​

/*

 * Per-device data

 */

​

struct emc6w201_data {

    struct i2c_client *client;

    struct mutex update_lock;

    char valid; /* zero until following fields are valid */

    unsigned long last_updated; /* in jiffies */

​

    /* registers values */

    u8 in[3][6];

    s8 temp[3][6];

    u16 fan[2][5];

};

​

/*

 * Combine LSB and MSB registers in a single value

 * Locking: must be called with data->update_lock held

 */

static u16 emc6w201_read16(struct i2c_client *client, u8 reg)

{

    int lsb, msb;

​

    lsb = i2c_smbus_read_byte_data(client, reg);

    msb = i2c_smbus_read_byte_data(client, reg + 1);

    if (unlikely(lsb < 0 || msb < 0)) {

        dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",

            16, "read", reg);

        return 0xFFFF;  /* Arbitrary value */

    }

​

    return (msb << 8) | lsb;

}

​

/*

 * Write 16-bit value to LSB and MSB registers

 * Locking: must be called with data->update_lock held

 */

static int emc6w201_write16(struct i2c_client *client, u8 reg, u16 val)

{

    int err;

​

    err = i2c_smbus_write_byte_data(client, reg, val & 0xff);

    if (likely(!err))

        err = i2c_smbus_write_byte_data(client, reg + 1, val >> 8);

    if (unlikely(err < 0))

        dev_err(&client->dev, "%d-bit %s failed at 0x%02x\n",

            16, "write", reg);

​

    return err;

}