imx: RS-485 problems during TX, maybe DMA related

[Clemens Gruber]

On Sat, Jan 07, 2017 at 02:48:03PM -0200, Fabio Estevam wrote:
> On Sat, Jan 7, 2017 at 1:34 PM, Clemens Gruber
> <clemens.gruber at pqgruber.com> wrote:
> > Hi Fabio,
> >
> > On Sat, Jan 07, 2017 at 12:57:10PM -0200, Fabio Estevam wrote:
> >> The MX6QDL_PAD_CSI0_DAT16__UART4_CTS_B option is only valid in dte mode.
> >
> > Ah, the input select is limited in that way, I see.
> >
> > You wrote that you tried rts-gpios.
> > What about setting cts-gpios to gpio6 2 in the DT?
> >
> > Or can you remux RX and TX to be switched to work in dte mode?
> 
> I managed to get RS485 in half-duplex working with rts-gios. Will send
> a patch shortly.

Great!

Did you observe the same effect I described, with the doubling of
characters in the front and the leftovers from previous transmissions at
the end?

Thanks,
Clemens