linux-imx

/*

 * Copyright (C) 2008, 2010 Davide Rizzo <elpa.rizzo@gmail.com>

 *

 * The LM95241 is a sensor chip made by National Semiconductors.

 * It reports up to three temperatures (its own plus up to two external ones).

 * Complete datasheet can be obtained from National's website at:

 *   http://www.national.com/ds.cgi/LM/LM95241.pdf

 *

 * 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.

 */

​

#include <linux/bitops.h>

#include <linux/err.h>

#include <linux/i2c.h>

#include <linux/init.h>

#include <linux/jiffies.h>

#include <linux/hwmon.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/slab.h>

​

#define DEVNAME "lm95241"

​

static const unsigned short normal_i2c[] = {

    0x19, 0x2a, 0x2b, I2C_CLIENT_END };

​

/* LM95241 registers */

#define LM95241_REG_R_MAN_ID        0xFE

#define LM95241_REG_R_CHIP_ID       0xFF

#define LM95241_REG_R_STATUS        0x02

#define LM95241_REG_RW_CONFIG       0x03

#define LM95241_REG_RW_REM_FILTER   0x06

#define LM95241_REG_RW_TRUTHERM     0x07

#define LM95241_REG_W_ONE_SHOT      0x0F

#define LM95241_REG_R_LOCAL_TEMPH   0x10

#define LM95241_REG_R_REMOTE1_TEMPH 0x11

#define LM95241_REG_R_REMOTE2_TEMPH 0x12

#define LM95241_REG_R_LOCAL_TEMPL   0x20

#define LM95241_REG_R_REMOTE1_TEMPL 0x21

#define LM95241_REG_R_REMOTE2_TEMPL 0x22

#define LM95241_REG_RW_REMOTE_MODEL 0x30

​

/* LM95241 specific bitfields */

#define CFG_STOP    BIT(6)

#define CFG_CR0076  0x00

#define CFG_CR0182  BIT(4)

#define CFG_CR1000  BIT(5)

#define CFG_CR2700  (BIT(4) | BIT(5))

#define CFG_CRMASK  (BIT(4) | BIT(5))

#define R1MS_MASK   BIT(0)

#define R2MS_MASK   BIT(2)

#define R1DF_MASK   BIT(1)

#define R2DF_MASK   BIT(2)

#define R1FE_MASK   BIT(0)

#define R2FE_MASK   BIT(2)

#define R1DM        BIT(0)

#define R2DM        BIT(1)

#define TT1_SHIFT   0

#define TT2_SHIFT   4

#define TT_OFF      0

#define TT_ON       1

#define TT_MASK     7

#define NATSEMI_MAN_ID  0x01

#define LM95231_CHIP_ID 0xA1

#define LM95241_CHIP_ID 0xA4

​

static const u8 lm95241_reg_address[] = {

    LM95241_REG_R_LOCAL_TEMPH,

    LM95241_REG_R_LOCAL_TEMPL,

    LM95241_REG_R_REMOTE1_TEMPH,

    LM95241_REG_R_REMOTE1_TEMPL,

    LM95241_REG_R_REMOTE2_TEMPH,

    LM95241_REG_R_REMOTE2_TEMPL

};

​

/* Client data (each client gets its own) */

struct lm95241_data {

    struct i2c_client *client;

    struct mutex update_lock;

    unsigned long last_updated; /* in jiffies */

    unsigned long interval;     /* in milli-seconds */

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

    /* registers values */

    u8 temp[ARRAY_SIZE(lm95241_reg_address)];