Introduction

How do you understand this line of code?

gpiod_direction_output(p->reset_gpio, 1);

If document is not read, it might be understood as driving the reset_gpio to high which, however, is not the case.

The active-low property

Please refer to document Documentation/gpio/consumer.txt, The active-low property section explains that 1 means logic active, while 0 means logic de-active. What turns our on the physical GPIO depends on the DTS setting:

If the GPIO is set as GPIO_ACTIVE_LOW, then 1 will drive to GPIO to low. If the GPIO is set as GPIO_ACTIVE_HIGH, then 1 will drive to GPIO to HIGH.

Suggestions

It is not obvious for the reader to understand the code and it is very confusing. Why does not the author define an macro?

GPIO_ACTIVE GPIO_DE_ACTIVE