I have looked into regmap-irq, it appears that using the default irq
thread_fn(regmap_irq_thread) is required. However, due to hardware limitation,
we need to inspect the IRQ_TYPE to determine whether to manage the irq within
the irq handler. I think our irq portion does not perfectly fit the regmap-irq.
Moreover, it seems that the gpio-regmap.c file needs to be modified if the GPIO driver
requires debounce settings. I think the gpio-regmap may not be appropriate for our driver.
Do you have any suggestions?