GPIO-driven RTS on TI hardware with 8250_omap driver

Ильяс Гасанов torso.nafi at
Sun Dec 27 05:43:07 PST 2015

Hi Matwey,

2015-12-27 16:14 GMT+03:00 Matwey V. Kornilov <matwey at>:
> The half of what is described here are implemented in my patches.
> But I cannot understand the other half. Each of six AM335x UARTs has
> RTS/CTS pins which are controlled by pinmux in device tree, no magic
> required here.

The problem here is, the appliance schematics are already designed in
such way that pins which can be configured as "native" RTS are not
used for RS485 control - the ones that are though may only be used as
GPIO flipped by software on transmission start/end for that purpose.
We simply cannot change the schematics on production because of this
issue alone.

Ilyas G.

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