I' m trying to get a rs485 bus working on a custom imx28 design. The problem that I' m facing is where to release the rs-485 bus in the linux code. How do I know that the uart is done sending its data? Is there a specific functions that gets called?
I don't find any function in mxs-auart.c which gets called after the device is done writing when using the 'screen' command in usermode.
Is there a possibility to set the irq, to trigger when the tx-buffer is empty?