2022-02-16 06:19:51

by Danilo Krummrich

Subject: [PATCH v3 2/3] dt-bindings: ps2-gpio: document bus signals open drain

The PS/2 bus defines data and clock line to be open drain, this should
be reflected in the gpio flags set in the binding.

Especially, this is important since the clock line sometimes is driven
by the host while being used as interrupt source.

Reviewed-by: Krzysztof Kozlowski <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
---
.../devicetree/bindings/serio/ps2-gpio.yaml | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/serio/ps2-gpio.yaml b/Documentation/devicetree/bindings/serio/ps2-gpio.yaml
index 304132fd30c5..a63d9172346f 100644
--- a/Documentation/devicetree/bindings/serio/ps2-gpio.yaml
+++ b/Documentation/devicetree/bindings/serio/ps2-gpio.yaml
@@ -15,12 +15,18 @@ properties:

data-gpios:
description:
- the gpio used for the data signal
+ the gpio used for the data signal - this should be flagged as
+ active high using open drain with (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)
+ from <dt-bindings/gpio/gpio.h> since the signal is open drain by
+ definition
maxItems: 1

clk-gpios:
description:
- the gpio used for the clock signal
+ the gpio used for the clock signal - this should be flagged as
+ active high using open drain with (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)
+ from <dt-bindings/gpio/gpio.h> since the signal is open drain by
+ definition
maxItems: 1

interrupts:
@@ -52,7 +58,7 @@ examples:
compatible = "ps2-gpio";
interrupt-parent = <&gpio>;
interrupts = <23 IRQ_TYPE_EDGE_FALLING>;
- data-gpios = <&gpio 24 GPIO_ACTIVE_HIGH>;
- clk-gpios = <&gpio 23 GPIO_ACTIVE_HIGH>;
+ data-gpios = <&gpio 24 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+ clk-gpios = <&gpio 23 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
write-enable;
};
--
2.35.1

2022-02-16 07:53:07

by Krzysztof Kozlowski

Subject: Re: [PATCH v3 2/3] dt-bindings: ps2-gpio: document bus signals open drain

On 15/02/2022 19:08, Danilo Krummrich wrote:
> The PS/2 bus defines data and clock line to be open drain, this should
> be reflected in the gpio flags set in the binding.
>
> Especially, this is important since the clock line sometimes is driven
> by the host while being used as interrupt source.
>
> Reviewed-by: Krzysztof Kozlowski <[email protected]>
> Signed-off-by: Danilo Krummrich <[email protected]>
> ---
> .../devicetree/bindings/serio/ps2-gpio.yaml | 14 ++++++++++----
> 1 file changed, 10 insertions(+), 4 deletions(-)
>


Reviewed-by: Krzysztof Kozlowski <[email protected]>


Best regards,
Krzysztof