[PATCH 1/2] dt-bindings: pinctrl: renesas,r9a09g077: Document pin configuration properties

Prabhakar
2025-10-14T19:11:38Z

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Document the pin configuration properties supported by the RZ/T2H pinctrl
driver. The RZ/T2H SoC supports configuring various electrical properties
through the DRCTLm (I/O Buffer Function Switching) registers.

Add documentation for the following standard properties:
- bias-disable, bias-pull-up, bias-pull-down: Control internal
pull-up/pull-down resistors (3 options: no pull, pull-up, pull-down)
- input-schmitt-enable, input-schmitt-disable: Control Schmitt trigger
input
- slew-rate: Control output slew rate (2 options: slow/fast)

Add documentation for the custom property:
- renesas,drive-strength: Control output drive strength using discrete
levels (0-3) representing low, medium, high, and ultra high strength.
This custom property is needed because the hardware uses fixed discrete
levels rather than configurable milliamp values.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
.../bindings/pinctrl/renesas,r9a09g077-pinctrl.yaml | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/Documentation/devicetree/bindings/pinctrl/renesas,r9a09g077-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/renesas,r9a09g077-pinctrl.yaml
index 36d665971484..9085d5cfb1c8 100644
--- a/Documentation/devicetree/bindings/pinctrl/renesas,r9a09g077-pinctrl.yaml
+++ b/Documentation/devicetree/bindings/pinctrl/renesas,r9a09g077-pinctrl.yaml
@@ -72,6 +72,19 @@ definitions:
input: true
input-enable: true
output-enable: true
+ bias-disable: true
+ bias-pull-down: true
+ bias-pull-up: true
+ input-schmitt-enable: true
+ input-schmitt-disable: true
+ slew-rate:
+ enum: [0, 1]
+ renesas,drive-strength:
+ description:
+ Drive strength configuration value. Valid values are 0 to 3, representing
+ increasing drive strength from low, medium, high and ultra high.
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [0, 1, 2, 3]
oneOf:
- required: [pinmux]
- required: [pins]
--
2.43.0