I'm trying to debug a kernel panic on an embedded device with no access to serial output. The device has a small notification LED which is supported by a driver in the Linux kernel.
So, I thought of porting
kernel/morse.c to Linux's LED subsystem (the original used something related to virtual terminal).
However, I've quickly ran into an issue. See, there is a
led_brightness_set() function which can be used to turn on/off the LED. It takes two arguments -
led_cdev (the LED device struct) and
brightness_value (brightness value).
I know how to set the
brightness_value but I don't know how to create/get
led_cdev. Is there a function for this?