2023-10-23 21:08:04

by Brenda Streiff

Subject: [PATCH v6 tty-next 1/2] dt-bindings: serial: ni,ni16650: add bindings

Add bindings for the NI 16550 UART.

Signed-off-by: Brenda Streiff <[email protected]>
Cc: Gratian Crisan <[email protected]>
Cc: Jason Smith <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
---
.../bindings/serial/ni,ni16550.yaml | 51 +++++++++++++++++++
1 file changed, 51 insertions(+)
create mode 100644 Documentation/devicetree/bindings/serial/ni,ni16550.yaml

diff --git a/Documentation/devicetree/bindings/serial/ni,ni16550.yaml b/Documentation/devicetree/bindings/serial/ni,ni16550.yaml
new file mode 100644
index 000000000000..72ab125dd892
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/ni,ni16550.yaml
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/serial/ni,ni16550.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NI 16550 asynchronous serial interface (UART)
+
+maintainers:
+ - Brenda Streiff <[email protected]>
+
+allOf:
+ - $ref: serial.yaml#
+
+properties:
+ compatible:
+ const: ni,ni16550
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ ni,serial-port-mode:
+ description: Indicates whether this is an RS-232 or RS-485 serial port.
+ $ref: /schemas/types.yaml#/definitions/string
+ enum: [ RS-232, RS-485 ]
+ default: RS-485
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+ serial@80000000 {
+ compatible = "ni,ni16550";
+ reg = <0x80000000 0x8>;
+ interrupts = <0 30 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&clk_uart>;
+ ni,serial-port-mode = "RS-232";
+ };
+...
--
2.30.2

2023-10-24 13:33:52

by Rob Herring (Arm)

Subject: Re: [PATCH v6 tty-next 1/2] dt-bindings: serial: ni,ni16650: add bindings

On Mon, Oct 23, 2023 at 04:04:56PM -0500, Brenda Streiff wrote:
> Add bindings for the NI 16550 UART.
>
> Signed-off-by: Brenda Streiff <[email protected]>
> Cc: Gratian Crisan <[email protected]>
> Cc: Jason Smith <[email protected]>
> Reviewed-by: Krzysztof Kozlowski <[email protected]>
> ---
> .../bindings/serial/ni,ni16550.yaml | 51 +++++++++++++++++++
> 1 file changed, 51 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/serial/ni,ni16550.yaml
>
> diff --git a/Documentation/devicetree/bindings/serial/ni,ni16550.yaml b/Documentation/devicetree/bindings/serial/ni,ni16550.yaml
> new file mode 100644
> index 000000000000..72ab125dd892
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/serial/ni,ni16550.yaml
> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/serial/ni,ni16550.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NI 16550 asynchronous serial interface (UART)

Is this significantly different than all the other 8250 compatible UARTs
in 8250.yaml?

> +
> +maintainers:
> + - Brenda Streiff <[email protected]>
> +
> +allOf:
> + - $ref: serial.yaml#
> +
> +properties:
> + compatible:
> + const: ni,ni16550
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + clocks:
> + maxItems: 1
> +
> + ni,serial-port-mode:
> + description: Indicates whether this is an RS-232 or RS-485 serial port.
> + $ref: /schemas/types.yaml#/definitions/string
> + enum: [ RS-232, RS-485 ]
> + default: RS-485

We already have 'linux,rs485-enabled-at-boot-time' which seems similar
purpose. It also tells me this is not a fixed in hardware setting. If
that property doesn't work for you, come up with something common and
explain why. Or explain why this is completely unique to this UART.

Rob