RS-485 in half-duplex mode

Oliver Graute oliver.graute at
Tue Nov 21 02:10:35 EST 2017

Hello list,

I try to use a RS-485 Interface with two wires on a imx28 CPU. Using the
driver in mxs-auart.c. I already modified my device tree to use
AUART4_RX and AUART4_TX for sending and receiving. This is working so
far. But since it is half-duplex the question arises how the switching
between sending and receiving is done. I have AUART4_RTS (GPIO2_26) for
this purpose. Is this something the driver can handle? do I have to
adjust my device tree or the driver for this setup? It is necessary to
handle this via IOCTL(TIOCSRS485) from user space?

Best Regards,


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