[PATCH v3 1/3] dt-bindings: leds: rt8515: Support single-GPIO flash ICs with vin supply

Rudraksha Gupta via B4 Relay
2026-03-26T07:57:33Z

Some flash ICs use the same one-wire pulse-count protocol as the RT8515
but have only a single enable line for both flash and torch modes, plus
an optional input voltage supply (e.g. a GPIO-controlled fixed
regulator) that gates power to the chip.

Make ent-gpios optional and add a vin-supply property to support these
variants. Add a oneOf constraint requiring exactly one of ent-gpios or
vin-supply. Add a binding example showing the single-GPIO configuration
with an input supply.

Assisted-by: Claude:claude-opus-4.6
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Linus Walleij <linusw@kernel.org>
Signed-off-by: Rudraksha Gupta <guptarud@gmail.com>
---
.../devicetree/bindings/leds/richtek,rt8515.yaml | 34 +++++++++++++++++++++-
1 file changed, 33 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml
index 0356371a6b01..ab3c5139132c 100644
--- a/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml
+++ b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml
@@ -15,6 +15,10 @@ description: |
current for each mode is defined in hardware using two resistors
RFS and RTS.

+ Some flash ICs use the same one-wire pulse-count protocol but have
+ only a single enable line for both flash and torch modes. For these
+ single-channel variants, only enf-gpios is needed.
+
properties:
compatible:
const: richtek,rt8515
@@ -26,6 +30,11 @@ properties:
ent-gpios:
maxItems: 1
description: A connection to the 'ENT' (enable torch) pin.
+ Not present on single-channel flash ICs that use only one enable
+ line for both flash and torch modes.
+
+ vin-supply:
+ description: Optional input supply for the flash IC.

richtek,rfs-ohms:
minimum: 7680
@@ -81,10 +90,15 @@ properties:

required:
- compatible
- - ent-gpios
- enf-gpios
- led

+oneOf:
+ - required:
+ - ent-gpios
+ - required:
+ - vin-supply
+
additionalProperties: false

examples:
@@ -108,4 +122,22 @@ examples:
};
};

+ - |
+ /* Single-channel flash IC with input supply */
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/leds/common.h>
+
+ led-controller {
+ compatible = "richtek,rt8515";
+ enf-gpios = <&tlmm 3 GPIO_ACTIVE_HIGH>;
+ vin-supply = <&flash_reg>;
+ richtek,rfs-ohms = <16000>;
+
+ led {
+ function = LED_FUNCTION_FLASH;
+ color = <LED_COLOR_ID_WHITE>;
+ flash-max-timeout-us = <250000>;
+ };
+ };
+
...

--
2.53.0