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/** * gpiod_get_direction - return the current direction of a GPIO * @desc: GPIO to get the direction of * * Return GPIOF_DIR_IN or GPIOF_DIR_OUT, or an error code in case of error. * * This function may sleep if gpiod_cansleep() is true. */int gpiod_get_direction(struct gpio_desc *desc){ struct gpio_chip *chip; unsigned  offset; int   status = -EINVAL;  chip = gpiod_to_chip(desc); offset = gpio_chip_hwgpio(desc);  if (!chip->get_direction)  return status;  status = chip->get_direction(chip, offset); if (status > 0) {  /* GPIOF_DIR_IN, or other positive */  status = 1;  clear_bit(FLAG_IS_OUT, &desc->flags); } if (status == 0) {  /* GPIOF_DIR_OUT */  set_bit(FLAG_IS_OUT, &desc->flags); } return status;}

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