Re: [PATCH 1/4] regulator: dt-bindings: Add Linear Technology LTM8054 regulator

David Lechner
2025-09-16T19:24:44Z

On 9/16/25 5:24 AM, Romain Gantois wrote:
> The Linear Technology LTM8054 is a Buck-Boost voltage regulator with an
> input range of 5V to 36V and an output range of 1.2V to 36V.
>
> The LTM8054's output voltage level is typically set using a voltage divider
> between the Vout and FB pins, the FB pin being constantly regulated to
> 1.2V.
>
> The output current limit of the LTM8054 may be statically set by placing a
> sense resistor on a dedicated pin. This limit can then be lowered by
> controlling the voltage level on the CTL pin.
>
> Describe the LTM8054 voltage regulator.
>
> Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
> ---
> .../bindings/regulator/lltc,ltm8054.yaml | 77 ++++++++++++++++++++++
> MAINTAINERS | 5 ++
> 2 files changed, 82 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/regulator/lltc,ltm8054.yaml b/Documentation/devicetree/bindings/regulator/lltc,ltm8054.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..4db11be178b0e662ec51f3d3d73202f8c32625d3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/regulator/lltc,ltm8054.yaml
> @@ -0,0 +1,77 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/regulator/lltc,ltm8054.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Linear Technology LTM8054 buck-boost regulator
> +
> +maintainers:
> + - Romain Gantois <romain.gantois@bootlin.com>
> +
> +description:
> + This regulator operates over an input voltage range of 5V to 36V, and can
> + output from 1.2V to 36V. The output voltage level is typically set with a
> + voltage divider between the Vout pin and the FB pin which is internally
> + regulated to 1.2V.
> +
> + The output current of the LTM8054 can be limited by tying the Iout pin to a
> + current sense resistor. This limit can be further lowered by applying a
> + voltage below 1.2V to the CTL pin.
> +
> +allOf:
> + - $ref: /schemas/regulator/regulator.yaml#
> +
> +properties:
> + compatible:
> + const: lltc,ltm8054

Looks like they got bought by Analog Devices Inc., so adi,ltm8054.

> +
> + enable-gpios:
> + description: GPIO connected to the RUN pin.
> + maxItems: 1
> +
> + lltc,fb-voltage-divider:
> + description:
> + An array of two integers containing the resistor values
> + R1 and R2 of the feedback voltage divider in Ohms.
> + $ref: /schemas/types.yaml#/definitions/uint32-array
> + minItems: 2
> + maxItems: 2
> +
> + lltc,iout-rsense-micro-ohms:
> + description:
> + Value of the output current sense resistor, in micro Ohms.
> +
> + io-channels:
> + items:
> + - description: DAC controlling the voltage level of the CTL pin.
> +
> + io-channel-names:
> + items:
> + - const: ctl
> +
> +required:
> + - compatible
> + - lltc,fb-voltage-divider
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/gpio/gpio.h>
> +
> + / {

Examples usually don't have a root node. Probably explains
the bot errors. (but you should have seen the same errors
locally with make dt_binding_check.)

> +
> + regulator {
> + compatible = "lltc,ltm8054";
> +
> + enable-gpios = <&gpio0 1 GPIO_ACTIVE_HIGH>;
> +
> + lltc,fb-voltage-divider = <1000000 68000>;
> +
> + lltc,iout-rsense-micro-ohms = <20000>;
> +
> + io-channels = <&dac 1>;
> + io-channel-names = "ctl";
> + };
> + };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index fe168477caa45799dfe07de2f54de6d6a1ce0615..7160179e6bf9d45a241582c1b6df8c0ebf6c3641 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -14517,6 +14517,11 @@ W: https://ez.analog.com/linux-software-drivers
> F: Documentation/devicetree/bindings/i2c/i2c-mux-ltc4306.txt
> F: drivers/i2c/muxes/i2c-mux-ltc4306.c
>
> +LTM8054 REGULATOR DRIVER
> +M: Romain Gantois <romain.gantois@bootlin.com>
> +S: Maintained
> +F: Documentation/devicetree/bindings/regulator/lltc,ltm8054.yaml
> +
> LTP (Linux Test Project)
> M: Andrea Cervesato <andrea.cervesato@suse.com>
> M: Cyril Hrubis <chrubis@suse.cz>
>