Hi @Mani, at the moment, I think that modify the device tree it's a little hard task for me. I only have a few weeks with Linux embedded. I'm reading the Embedded Linux Primer, so may, in some weeks more I will be capable.
At the moment, I read the GPIO, then I write the value to notify the salve, and finally I do a "dummy" read, so the slave can put the line down again. Thank you for the tip