On 11/7/25 19:16, Conor Dooley wrote:
On Fri, Nov 07, 2025 at 01:49:58PM +0100, Maud Spierings via B4 Relay wrote:
From: Maud Spierings <[email protected]>
The Maxim MAX25014 is a 4-channel automotive grade backlight driver IC
with integrated boost controller.
Signed-off-by: Maud Spierings <[email protected]>
---
In the current implementation the control registers for channel 1,
control all channels. So only one led subnode with led-sources is
supported right now. If at some point the driver functionality is
expanded the bindings can be easily extended with it.
I'm sorry if I asked this before and forgot or w/e, but how backwards
compatible is this? If they control all channels and it gets changed to
only control channel one, how will a changed kernel understand the
difference between a new devicetree that only wants to control channel 1
and an old devicetree that is trying to use channel 1 to control all
channels?
The idea is that an implementation like that will add multiple led@
subnodes without the led-sources property.
So devicetrees controlled by one channel will still have only one led
with multiple sources in the devicetree.
Kind regards,
Maud
---
.../bindings/leds/backlight/maxim,max25014.yaml | 107 +++++++++++++++++++++
MAINTAINERS | 5 +
2 files changed, 112 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 000000000000..e83723224b07
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/maxim,max25014.yaml
@@ -0,0 +1,107 @@
+# 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 <[email protected]>
+
+properties:
+ compatible:
+ enum:
+ - maxim,max25014
+
+ reg:
+ maxItems: 1
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+ 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
+ default: 11
+ description:
+ Value of the ISET field in the ISET register. This controls the current
+ scale of the outputs, a higher number means more current.
+
+ led@0:
+ type: object
+ description: Properties for a string of connected LEDs.
+ $ref: common.yaml#
+
+ properties:
+ reg:
+ const: 0
+
+ led-sources:
+ allOf:
+ - minItems: 1
+ maxItems: 4
+ items:
+ minimum: 0
+ maximum: 3
+ default: [0, 1, 2, 3]
+
+ default-brightness:
+ minimum: 0
+ maximum: 100
+ default: 50
+
+ required:
+ - reg
+
+ additionalProperties: false
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ backlight@6f {
+ compatible = "maxim,max25014";
+ reg = <0x6f>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ enable-gpios = <&gpio1 4 GPIO_ACTIVE_HIGH>;
+ interrupt-parent = <&gpio1>;
+ interrupts = <2 IRQ_TYPE_EDGE_FALLING>;
+ power-supply = <®_backlight>;
+ pwms = <&pwm1>;
+ maxim,iset = <7>;
+
+ led@0 {
+ reg = <0>;
+ led-sources = <0 1 2 3>;
+ default-brightness = <50>;
+ };
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 58c7e3f678d8..606ce086f758 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15261,6 +15261,11 @@ 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 <[email protected]>
+S: Maintained
+F: Documentation/devicetree/bindings/leds/backlight/maxim,max25014.yaml
+
MAX31335 RTC DRIVER
M: Antoniu Miclaus <[email protected]>
L: [email protected]
--
2.51.2
