/* chip initialize */
 static int __devinit lm3642_chip_init(struct lm3642_chip_data *chip)
 {
-       unsigned int reg_val;
        int ret;
        struct lm3642_platform_data *pdata = chip->pdata;
 
        /* set enable register */
-       ret = regmap_read(chip->regmap, REG_ENABLE, ®_val);
+       ret = regmap_update_bits(chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
+                                pdata->tx_pin);
        if (ret < 0)
-               goto out;
-
-       reg_val &= (~EX_PIN_ENABLE_MASK);
-       reg_val |= pdata->tx_pin;
-       ret = regmap_write(chip->regmap, REG_ENABLE, reg_val);
-       if (ret < 0)
-               goto out;
-
-out:
-       dev_err(chip->dev, "Failed to read REG_ENABLE Register\n");
+               dev_err(chip->dev, "Failed to update REG_ENABLE Register\n");
        return ret;
 }