Add bindings for a generic 7-segment LED display using GPIOs.
Signed-off-by: Chris Packham <[email protected]>
---
Notes:
Changes in v4:
- Add ASCII art diagram showing arrangement of segments
Changes in v3:
- Set maxItems: 7
- Expand description of segment-gpios property.
- Use compatible = "gpio-7-segment" as suggested by Rob
Changes in v2:
- Use compatible = "generic-gpio-7seg" to keep checkpatch.pl happy
.../bindings/auxdisplay/gpio-7-segment.yaml | 54 +++++++++++++++++++
1 file changed, 54 insertions(+)
create mode 100644 Documentation/devicetree/bindings/auxdisplay/gpio-7-segment.yaml
diff --git a/Documentation/devicetree/bindings/auxdisplay/gpio-7-segment.yaml b/Documentation/devicetree/bindings/auxdisplay/gpio-7-segment.yaml
new file mode 100644
index 000000000000..172548dfb142
--- /dev/null
+++ b/Documentation/devicetree/bindings/auxdisplay/gpio-7-segment.yaml
@@ -0,0 +1,54 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/auxdisplay/gpio-7-segment.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: GPIO based LED segment display
+
+maintainers:
+ - Chris Packham <[email protected]>
+
+properties:
+ compatible:
+ const: gpio-7-segment
+
+ segment-gpios:
+ description:
+ An array of GPIOs one per segment. The first GPIO corresponds to the A
+ segment the last GPIO corresponds to the G segment. Some LED blocks also
+ have a decimal point (currently ignored).
+
+ -a-
+ | |
+ f b
+ | |
+ -g-
+ | |
+ e c
+ | |
+ -d- dp
+
+ minItems: 7
+ maxItems: 7
+
+required:
+ - segment-gpios
+
+additionalProperties: false
+
+examples:
+ - |
+
+ #include <dt-bindings/gpio/gpio.h>
+
+ led-7seg {
+ compatible = "gpio-7-segment";
+ segment-gpios = <&gpio 0 GPIO_ACTIVE_LOW
+ &gpio 1 GPIO_ACTIVE_LOW
+ &gpio 2 GPIO_ACTIVE_LOW
+ &gpio 3 GPIO_ACTIVE_LOW
+ &gpio 4 GPIO_ACTIVE_LOW
+ &gpio 5 GPIO_ACTIVE_LOW
+ &gpio 6 GPIO_ACTIVE_LOW>;
+ };
--
2.43.2
Hi Chris,
On Tue, Mar 5, 2024 at 4:59 AM Chris Packham
<[email protected]> wrote:
> Add bindings for a generic 7-segment LED display using GPIOs.
>
> Signed-off-by: Chris Packham <[email protected]>
> ---
>
> Notes:
> Changes in v4:
> - Add ASCII art diagram showing arrangement of segments
Thanks for the update!
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/auxdisplay/gpio-7-segment.yaml
> @@ -0,0 +1,54 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/auxdisplay/gpio-7-segment.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: GPIO based LED segment display
> +
> +maintainers:
> + - Chris Packham <[email protected]>
> +
> +properties:
> + compatible:
> + const: gpio-7-segment
> +
> + segment-gpios:
> + description:
Please add "|", as you want to preserve the formatting of the diagram.
> + An array of GPIOs one per segment. The first GPIO corresponds to the A
> + segment the last GPIO corresponds to the G segment. Some LED blocks also
.. segment, the ...
> + have a decimal point (currently ignored).
> +
> + -a-
> + | |
> + f b
> + | |
> + -g-
> + | |
> + e c
> + | |
> + -d- dp
> +
> + minItems: 7
> + maxItems: 7
I guess it doesn't hurt to have "maxItems: 8", so people don't have
to update their DTS later when support for the DP is added?
That would need an update to the description above, as the last segment
would then be either G or DP.
> +
> +required:
> + - segment-gpios
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> +
> + #include <dt-bindings/gpio/gpio.h>
> +
> + led-7seg {
> + compatible = "gpio-7-segment";
> + segment-gpios = <&gpio 0 GPIO_ACTIVE_LOW
> + &gpio 1 GPIO_ACTIVE_LOW
> + &gpio 2 GPIO_ACTIVE_LOW
> + &gpio 3 GPIO_ACTIVE_LOW
> + &gpio 4 GPIO_ACTIVE_LOW
> + &gpio 5 GPIO_ACTIVE_LOW
> + &gpio 6 GPIO_ACTIVE_LOW>;
Please group GPIO specifiers using angular brackets:
segment-gpios = <&gpio 0 GPIO_ACTIVE_LOW>,
<&gpio 1 GPIO_ACTIVE_LOW>,
...
> + };
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68korg
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds