linux-imx

/*

 * smsc47m192.c - Support for hardware monitoring block of

 *        SMSC LPC47M192 and compatible Super I/O chips

 *

 * Copyright (C) 2006  Hartmut Rick <linux@rick.claranet.de>

 *

 * Derived from lm78.c and other chip drivers.

 *

 * 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.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 */

​

#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/hwmon-vid.h>

#include <linux/err.h>

#include <linux/sysfs.h>

#include <linux/mutex.h>

​

/* Addresses to scan */

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

​

/* SMSC47M192 registers */

#define SMSC47M192_REG_IN(nr)       ((nr) < 6 ? (0x20 + (nr)) : \

                    (0x50 + (nr) - 6))

#define SMSC47M192_REG_IN_MAX(nr)   ((nr) < 6 ? (0x2b + (nr) * 2) : \

                    (0x54 + (((nr) - 6) * 2)))

#define SMSC47M192_REG_IN_MIN(nr)   ((nr) < 6 ? (0x2c + (nr) * 2) : \

                    (0x55 + (((nr) - 6) * 2)))

static u8 SMSC47M192_REG_TEMP[3] =  { 0x27, 0x26, 0x52 };

static u8 SMSC47M192_REG_TEMP_MAX[3] =  { 0x39, 0x37, 0x58 };

static u8 SMSC47M192_REG_TEMP_MIN[3] =  { 0x3A, 0x38, 0x59 };

#define SMSC47M192_REG_TEMP_OFFSET(nr)  ((nr) == 2 ? 0x1e : 0x1f)

#define SMSC47M192_REG_ALARM1       0x41

#define SMSC47M192_REG_ALARM2       0x42

#define SMSC47M192_REG_VID      0x47

#define SMSC47M192_REG_VID4     0x49

#define SMSC47M192_REG_CONFIG       0x40

#define SMSC47M192_REG_SFR      0x4f

#define SMSC47M192_REG_COMPANY_ID   0x3e

#define SMSC47M192_REG_VERSION      0x3f

​

/* generalised scaling with integer rounding */

static inline int SCALE(long val, int mul, int div)

{

    if (val < 0)

        return (val * mul - div / 2) / div;

    else

        return (val * mul + div / 2) / div;

}

​

/* Conversions */

​

/* smsc47m192 internally scales voltage measurements */

static const u16 nom_mv[] = { 2500, 2250, 3300, 5000, 12000, 3300, 1500, 1800 };

​

static inline unsigned int IN_FROM_REG(u8 reg, int n)

{

    return SCALE(reg, nom_mv[n], 192);

}

​

static inline u8 IN_TO_REG(unsigned long val, int n)

{

    val = clamp_val(val, 0, nom_mv[n] * 255 / 192);

    return SCALE(val, 192, nom_mv[n]);

}

​

/*

 * TEMP: 0.001 degC units (-128C to +127C)

 * REG: 1C/bit, two's complement

 */

static inline s8 TEMP_TO_REG(long val)

{

    return SCALE(clamp_val(val, -128000, 127000), 1, 1000);

}

​