2022-07-21 09:32:53

by Marcus Folkesson

Subject: [PATCH 2/2] dt-bindings: gpio: fairchild,74hc595: add strobe-gpios property

Some shift registers (74hc4094 for example) has a strobe signal to latch
data from the serial input to the parallel output.

Add an optional strobe-gpios property to support those chips.

Signed-off-by: Marcus Folkesson <[email protected]>
---
.../devicetree/bindings/gpio/fairchild,74hc595.yaml | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml b/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml
index a99e7842ca17..9893df9ae22c 100644
--- a/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml
+++ b/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml
@@ -14,6 +14,8 @@ properties:
enum:
- fairchild,74hc595
- nxp,74lvc594
+ - ti,cd54hc4094
+ - ti,cd74hc4094

reg:
maxItems: 1
@@ -33,6 +35,10 @@ properties:
description: GPIO connected to the OE (Output Enable) pin.
maxItems: 1

+ strobe-gpios:
+ description: GPIO connected to the STROBE pin
+ maxItems: 1
+
spi-max-frequency: true

patternProperties:
--
2.36.1

2022-07-21 10:21:41

by Krzysztof Kozlowski

Subject: Re: [PATCH 2/2] dt-bindings: gpio: fairchild,74hc595: add strobe-gpios property

On 21/07/2022 11:34, Marcus Folkesson wrote:
> Some shift registers (74hc4094 for example) has a strobe signal to latch
> data from the serial input to the parallel output.
>
> Add an optional strobe-gpios property to support those chips.
>
> Signed-off-by: Marcus Folkesson <[email protected]>
> ---
> .../devicetree/bindings/gpio/fairchild,74hc595.yaml | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml b/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml
> index a99e7842ca17..9893df9ae22c 100644
> --- a/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml
> +++ b/Documentation/devicetree/bindings/gpio/fairchild,74hc595.yaml
> @@ -14,6 +14,8 @@ properties:
> enum:
> - fairchild,74hc595
> - nxp,74lvc594
> + - ti,cd54hc4094
> + - ti,cd74hc4094
>
> reg:
> maxItems: 1
> @@ -33,6 +35,10 @@ properties:
> description: GPIO connected to the OE (Output Enable) pin.
> maxItems: 1
>
> + strobe-gpios:
> + description: GPIO connected to the STROBE pin
> + maxItems: 1

This should be disallowed (in allOf:if:then) for variants which do not
support it (or do not have even STROBE pin).


Best regards,
Krzysztof

2022-07-26 08:29:15

by Linus Walleij

Subject: Re: [PATCH 2/2] dt-bindings: gpio: fairchild,74hc595: add strobe-gpios property

On Thu, Jul 21, 2022 at 11:30 AM Marcus Folkesson
<[email protected]> wrote:

> Some shift registers (74hc4094 for example) has a strobe signal to latch
> data from the serial input to the parallel output.
>
> Add an optional strobe-gpios property to support those chips.
>
> Signed-off-by: Marcus Folkesson <[email protected]>

As pointed out in discussion with Andy, let's drop this and just
use cs-gpios as-is.

Yours,
Linus Walleij