I think I understand what you are trying to say so far. I did not have too much
experience related to gpio. I will set pull_up register in .set_config
However, I did not understand where its parameters come from.
set_config(struct gpio_chip *chip, unsigned int offset,
unsigned long config)
It might be trivial question, but Where does config come from?
At the end, I should rewrite the code using regmap_gpio, right? So if I rewrite
code using regmap_gpio, how can I replace set_config(...)?