On 8/19/25 21:50, Rob Herring wrote:

On Tue, Aug 19, 2025 at 12:58:59PM +0200, Maud Spierings wrote:

quoted

The Maxim MAX25014 is a 4-channel automotive grade backlight driver IC
with intgrated boost controller.

Signed-off-by: Maud Spierings <maudspierings@gocontroll.com>
---
  .../bindings/leds/backlight/maxim,max25014.yaml    | 79 ++++++++++++++++++++++
  MAINTAINERS                                        |  5 ++
  2 files changed, 84 insertions(+)

diff --git a/Documentation/devicetree/bindings/leds/backlight/maxim,max25014.yaml b/Documentation/devicetree/bindings/leds/backlight/maxim,max25014.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..30b591152fa31d5e43243cac44c72028b05b5f8a
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/maxim,max25014.yaml

@@ -0,0 +1,79 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/backlight/maxim,max25014.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Maxim max25014 backlight controller
+
+maintainers:
+  - Maud Spierings <maudspierings@gocontroll.com>
+
+allOf:
+  - $ref: common.yaml#
+
+properties:
+  compatible:
+    enum:
+      - maxim,max25014
+
+  reg:
+    maxItems: 1
+
+  enable-gpios:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  power-supply:
+    description: Regulator which controls the boost converter input rail.
+
+  pwms:
+    maxItems: 1
+
+  maxim,iset:
+    $ref: /schemas/types.yaml#/definitions/uint32

        maximum: 15

done

quoted

+    default: 11
+    description:
+      Value of the ISET register field (0-15).

Perhaps a little on what this controls?

done, for now, it controls the current scale of the backlight, higher 
number = more current. But I will put it in the description in v3

quoted

+
+  maxim,strings:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    description:
+      A 4-bit bitfield that describes which led strings to turn on.
+    minItems: 4
+    maxItems: 4

        items:
          maximum: 1

But why not just an 8-bit value 0x0-0xF?

That is possible too, the logic is inverted in the actual chip, a bit 
set means the string is turned off, but that can be solved with a 
bitwise not. This just felt like a natural way to read/edit it, an 8-bit 
value you have to first translate the bits into a hex value which isn't 
very clear about what it is actually doing.

Is it possible to to 0b0111 notation in a devicetree? That would make it 
better at least.

quoted

+
+required:
+  - compatible
+  - reg
+  - maxim,strings
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        backlight: backlight@6f {

Drop unused labels.

oops dropped

quoted

+            reg = <0x6f>;
+            compatible = "maxim,max25014";

compatible is always first.

Messed that up in the dtsos too, fixed everywhere in v3

quoted

+            default-brightness = <50>;
+            enable-gpios = <&gpio1 4 GPIO_ACTIVE_HIGH>;
+            interrupt-parent = <&gpio1>;
+            interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
+            pinctrl-names = "default";
+            pinctrl-0 = <&pinctrl_backlight>;

Generally we don't put pinctrl properties in examples as they are always
allowed.

dropped

quoted

+            power-supply = <&reg_backlight>;
+            pwms = <&pwm1>;
+            maxim,iset = <7>;
+            maxim,strings = <1 1 1 1>;
+        };
+    };
+

diff --git a/MAINTAINERS b/MAINTAINERS
index e81d5f9fbd16cc384356804390d65652bbb9e3f6..11c73d2e37fac22aea852152746236c1472f41b8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS

@@ -14972,6 +14972,11 @@ F:	Documentation/userspace-api/media/drivers/max2175.rst
  F:	drivers/media/i2c/max2175*
  F:	include/uapi/linux/max2175.h
  
+MAX25014 BACKLIGHT DRIVER
+M:	Maud Spierings <maudspierings@gocontroll.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/leds/backlight/maxim,max25014.yaml
+
  MAX31335 RTC DRIVER
  M:	Antoniu Miclaus <antoniu.miclaus@analog.com>
  L:	linux-rtc@vger.kernel.org

-- 
2.50.1

Thanks for your review!
Kind regards,
Maud