Re: [PATCH v1 1/2] dt-bindings: backlight: gpio-backlight: allow multiple GPIOs

On 14-01-2026 21:23, Daniel Thompson wrote:

On Tue, Jan 13, 2026 at 10:15:53AM +0530, tessolveupstream@gmail.com wrote:

quoted

On 05-01-2026 15:25, Daniel Thompson wrote:

quoted

On Mon, Jan 05, 2026 at 02:21:19PM +0530, Sudarshan Shetty wrote:

quoted

Update the gpio-backlight binding to support configurations that require
more than one GPIO for enabling/disabling the backlight.

Signed-off-by: Sudarshan Shetty <redacted>
---
 .../bindings/leds/backlight/gpio-backlight.yaml      | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml
index 584030b6b0b9..1483ce4a3480 100644
--- a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml
+++ b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml

@@ -17,7 +17,8 @@ properties:

   gpios:
     description: The gpio that is used for enabling/disabling the backlight.
-    maxItems: 1
+    minItems: 1
+    maxItems: 2

Why 2?

In the current design, the LVDS panel has a single backlight that
is controlled by two GPIOs. Initially, It described as two separate
backlight devices using the same gpio-backlight driver, since the
existing driver supports only one GPIO per instance.

So the maintainer suggested to extend the gpio-backlight driver
and bindings to support multiple GPIOs.
https://lore.kernel.org/all/q63bdon55app4gb2il5e7skyc6z2amcnaiqbqlhen7arkxphtb@3jejbelji2ti/ (local)

Right. So, once we support multiple GPIOs then why limit it to 2?

Okay, got the point. I'm removing the maxItems constraint entirely 
to allow any number of GPIOs as below:

diff --git a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml
index 1483ce4a3480..82698519daff 100644
--- a/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml
+++ b/Documentation/devicetree/bindings/leds/backlight/gpio-backlight.yaml

@@ -16,9 +16,11 @@ properties:
     const: gpio-backlight

   gpios:
-    description: The gpio that is used for enabling/disabling the backlight.
+    description: |
+      The gpio that is used for enabling/disabling the backlight.
+      Multiple GPIOs can be specified for panels that require several
+      enable signals.
     minItems: 1
-    maxItems: 2

   default-on:
     description: enable the backlight at boot.

Does this approach work for you?

Daniel.