[BUG] gpio: gpio-adp5588: A possible sleep-in-atomic-context bug in adp5588_gpio_direction_input()

[Jia-Ju Bai]

The driver may sleep with holding a spinlock.

The function call paths (from bottom to top) in Linux-4.16 are:

[FUNC] mutex_lock_nested
drivers/gpio/gpio-adp5588.c, 113: mutex_lock_nested in 
adp5588_gpio_direction_input
drivers/gpio/gpio-adp5588.c, 224: adp5588_gpio_direction_input in 
adp5588_irq_set_type
kernel/irq/manage.c, 686: [FUNC_PTR]adp5588_irq_set_type in 
__irq_set_trigger
kernel/irq/manage.c, 1350: __irq_set_trigger in __setup_irq
kernel/irq/manage.c, 1238: _raw_spin_lock_irqsave in __setup_irq

Note that [FUNC_PTR] means a function pointer call is used.

I do not find a good way to fix, so I only report.
This is found by my static analysis tool (DSAC).


Best wishes,
Jia-Ju Bai