On Sun, Apr 7, 2019 at 10:26 PM Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxx> wrote: > > Hi Rob, > Thanks for the review. > > On Sat, Apr 6, 2019 at 11:36 AM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > On Tue, Apr 02, 2019 at 10:36:17AM +0530, shubhrajyoti.datta@xxxxxxxxx wrote: > > > From: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxxx> > > > > > > Vivado has a configurationo for selecting the flow control. > > > > Vivado is ? > > > > > Add a dt binding to check for the same. > > > > > > Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxxx> > > > --- > > > Documentation/devicetree/bindings/serial/cdns,uart.txt | 4 ++++ > > > 1 file changed, 4 insertions(+) > > > > > > diff --git a/Documentation/devicetree/bindings/serial/cdns,uart.txt b/Documentation/devicetree/bindings/serial/cdns,uart.txt > > > index 227bb77..5161a05 100644 > > > --- a/Documentation/devicetree/bindings/serial/cdns,uart.txt > > > +++ b/Documentation/devicetree/bindings/serial/cdns,uart.txt > > > @@ -12,6 +12,10 @@ Required properties: > > > See ../clocks/clock-bindings.txt for details. > > > > > > > > > +Optional properties: > > > +- xlnx,nortscts: The presence of this property indicates that the > > > + UART does not support modem lines for RTS/CTS hardware flow control. > > > > We already have 'uart-has-rtscts'. Please use that. Maybe you need a new > > compatible as I'd guess current users assume RTS/CTS is present. > > the setting in vivado (tool helps configure the board) which says no > flowcontrol. > this just keeps the lines in a unknown state. > > this issue with 'uart-has-rtscts' is backward compatibility > current code assumes rts / cts is > present. If not preset then it will return false. So I thought of > having a property with the inverse. Searching more, we also have 'cts-override' (in snps-dw-apb-uart.txt). How about using that? You don't really need to care about RTS as setting it will just have no effect. Rob
