| Message ID | 1554181578-13362-2-git-send-email-shubhrajyoti.datta@gmail.com |
|---|---|
| State | Changes Requested, archived |
| Headers | show |
| Series | serial: uartps: Make flowcontrol configurable | expand |
| Context | Check | Description |
|---|---|---|
| robh/checkpatch | success |
On Tue, Apr 02, 2019 at 10:36:17AM +0530, shubhrajyoti.datta@gmail.com wrote: > From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> > > 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@xilinx.com> > --- > 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. > + > Example: > uart@e0000000 { > compatible = "cdns,uart-r1p8"; > -- > 2.1.1 >
Hi Rob, Thanks for the review. On Sat, Apr 6, 2019 at 11:36 AM Rob Herring <robh@kernel.org> wrote: > > On Tue, Apr 02, 2019 at 10:36:17AM +0530, shubhrajyoti.datta@gmail.com wrote: > > From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> > > > > 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@xilinx.com> > > --- > > 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. > > > + > > Example: > > uart@e0000000 { > > compatible = "cdns,uart-r1p8"; > > -- > > 2.1.1 > > >
On Sun, Apr 7, 2019 at 10:26 PM Shubhrajyoti Datta <shubhrajyoti.datta@gmail.com> wrote: > > Hi Rob, > Thanks for the review. > > On Sat, Apr 6, 2019 at 11:36 AM Rob Herring <robh@kernel.org> wrote: > > > > On Tue, Apr 02, 2019 at 10:36:17AM +0530, shubhrajyoti.datta@gmail.com wrote: > > > From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> > > > > > > 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@xilinx.com> > > > --- > > > 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
Hi Rob, Thanks for the review. On Sat, Apr 6, 2019 at 11:36 AM Rob Herring <robh@kernel.org> wrote: > > On Tue, Apr 02, 2019 at 10:36:17AM +0530, shubhrajyoti.datta@gmail.com wrote: > > From: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> > > > > 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@xilinx.com> > > --- > > 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. > Current behavior is it is with 'uart-has-rtscts . However to keep backward compatibility. I added nortscts . Let me know if we can tackle that or can we change the default behavior? > > + > > Example: > > uart@e0000000 { > > compatible = "cdns,uart-r1p8"; > > -- > > 2.1.1 > > >
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. + Example: uart@e0000000 { compatible = "cdns,uart-r1p8";