Re: [PATCHv4 2/3] tty/serial: at91: fix hardware handshake with GPIOs

From: Alexandre Belloni
Date: Fri Sep 30 2016 - 07:54:50 EST


On 30/09/2016 at 13:45:47 +0200, Richard Genoud wrote :
> 2016-09-30 13:16 GMT+02:00 Alexandre Belloni
> <alexandre.belloni@xxxxxxxxxxxxxxxxxx>:
> > On 30/09/2016 at 13:04:28 +0200, Richard Genoud wrote :
> >> Anyway, the problematics setups are all the setups with USMODE_HWHS
> >> enabled on platform without Fifos or PDC,
> >> i.e. all platforms but sama5d2 (Cyrille, correct me if I'm wrong).
> >>
> >
> > This is a wrong assumption, at91rm9200 to at91sam9g45 all have a pdc.
> > Please, don't break those platforms.
> >
> > The only affected platforms are sam9x5, sama5d3 and sama5d4.
> Have you tested them ?
>
> And why are you saying that rm9200 and g45 will be broken with this patch ?
> If they have a pdc, they will fall in the case:
> (atmel_use_pdc_rx(port) || atmel_use_fifo(port))
> and thus use:
> mode |= ATMEL_US_USMODE_HWHS;
>
> won't they ?

Well, this patch wouldn't have my ack if it was breaking them. However,
I'm still not sure about 3/3.

--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com