cx231xx_gpio_i2c_read
dev->cx231xx_gpio_i2c_read = cx231xx_gpio_i2c_read;
dev->cx231xx_gpio_i2c_read(dev, msg->addr,
dev->cx231xx_gpio_i2c_read(dev, msg2->addr,
int (*cx231xx_gpio_i2c_read) (struct cx231xx *dev, u8 dev_addr,
int cx231xx_gpio_i2c_read(struct cx231xx *dev, u8 dev_addr, u8 *buf, u8 len);