i'm kind of strapped for time this week so i'm going to shamelessly
ask if someone can point me at the simplest variant of a loadable
module that will let me turn on/off one of the four LEDs on a BBB from
*kernel* space. user space is easy -- that's explained in a number of
places like this:
http://elinux.org/EBC_Exercise_10_Flashing_an_LED
based on my perusal of the code under drivers/leds, i can already
see the global list of leds in the variable "leds_list", and how one
can loop through the list of LEDs in led-triggers.c with:
down_read(&leds_list_lock);
list_for_each_entry(led_cdev, &leds_list, node) {
down_write(&led_cdev->trigger_lock);
if (!led_cdev->trigger && led_cdev->default_trigger &&
!strcmp(led_cdev->default_trigger, trig->name))
led_trigger_set(led_cdev, trig);
up_write(&led_cdev->trigger_lock);
}
up_read(&leds_list_lock);
so i'm sure i could eventually tease out what i need, but if someone
else already has something like that, that would be just ducky.
rday