adt7410.c

[詳解]

/** @file
    @brief      ADT7410 ドライバ(I2C I/F)

    @date       2014.12.14
    @author     Takashi SHUDO
*/

#include "sysconfig.h"
#include "device.h"
#include "interrupt.h"
#include "tkprintf.h"
#include "str.h"
#include "device/i2c_ioctl.h"
#include "device/envsnsr_ioctl.h"

//#define DEBUGKBITS 0x03
#include "dkprintf.h"


#define REG_TEMP_MSB    0x00
#define REG_TEMP_LSB    0x01
#define REG_STATUS      0x02
#define REG_CONFIG      0x03

#define DEV_ADDR        0x48

static struct st_device *i2c_dev;
static char dev_name[MAX_DEVNAMELRN];

static int adt7410_register(struct st_device *dev, char *param)
{
        strncopy((uchar *)dev_name, (uchar *)param, MAX_DEVNAMELRN);

        i2c_dev = open_device(dev_name);
        if(i2c_dev == 0) {
                SYSERR_PRINT("Cannot open device \"%s\"\n", dev_name);
                return -1;
        }

        close_device(i2c_dev);

        return 0;
}

static int get_temp(void)
{
        unsigned short val = 0;
        unsigned char data[2];
        int temp;
        int th, tl;

        lock_device(i2c_dev, 0);

        ioctl_device(i2c_dev, IOCMD_I2C_SLAVE_ADDR7, DEV_ADDR, 0);
        ioctl_device(i2c_dev, IOCMD_I2C_MEMADDRSIZE, I2C_MEM_ADDR_SIZE_8BIT, 0);
        seek_device(i2c_dev, 0, SEEK_SET);
        read_device(i2c_dev, data, 2);

        unlock_device(i2c_dev);

        val = ((((unsigned short)data[0] << 8) + data[1]) >> 3);

        temp = (int)val;
        if(val & (0x8000 >> 3)) {       // 符号判定
                temp = temp - 8192;     // 負数のとき
        }

        th = temp/16;
        tl = (val & 15) * 10 / 16;

        return (th * 100) + (tl * 10);
}

static int adt7410_ioctl(struct st_device *dev, unsigned int com, unsigned int arg, void *param)
{
        switch(com) {
        case IOCMD_ENVSNSR_GET_TEMP:
                {
                        int rtn = get_temp();
                        DKPRINTF(0x01, "ENVSNSR_GET_TEMP %d\n", rtn);
                        return rtn;
                }

        case IOCMD_ENVSNSR_GET_THP:
                {
                        int *thp = param;
                        thp[0] = get_temp();
                        thp[1] = 0;
                        thp[2] = 0;
                        DKPRINTF(0x01, "ENVSNSR_GET_THP T:%d H:%d P:%d\n", thp[0], thp[1], thp[2]);
                        return 0;
                }

        default:
                SYSERR_PRINT("Unknown ioctl(%08X)\n", com);
                return -1;
        }

        return 0;
}

const struct st_device adt7410_device = {
        .name           = DEF_DEV_NAME_ENVSNSR,
        .explan         = "ATD7410 I2C Temperature Sensor",
        .register_dev   = adt7410_register,
        .ioctl          = adt7410_ioctl,
};