Re: [PATCH 1/2] dt-bindings: thermal: qcom: add pm8901-temp-alarm

[Dmitry Baryshkov]

On Sat, May 30, 2026 at 04:00:39PM +0200, Herman van Hazendonk wrote:
> Add the binding for the temperature-alarm block inside the Qualcomm
> PM8901 PMIC (companion to the PM8058 on MSM8x60). The driver exposes
> the PM8901 die-temperature trip stages (105 / 125 / 145 C) to the
> thermal framework via a thermal-zone, with stage 3 wired as a
> critical trip so the kernel issues orderly_poweroff() when the part
> overheats.
> 
> The binding describes the SSBI sub-node address, the GIC interrupt
> the alarm raises on a stage transition, and the parent PMIC
> reference.
> 
> Signed-off-by: Herman van Hazendonk <github.com@xxxxxxxxxx>
> ---
>  .../thermal/qcom,pm8901-temp-alarm.yaml       | 79 +++++++++++++++++++
>  1 file changed, 79 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/thermal/qcom,pm8901-temp-alarm.yaml
> 
> diff --git a/Documentation/devicetree/bindings/thermal/qcom,pm8901-temp-alarm.yaml b/Documentation/devicetree/bindings/thermal/qcom,pm8901-temp-alarm.yaml
> new file mode 100644
> index 000000000000..569943b4aedc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/qcom,pm8901-temp-alarm.yaml
> @@ -0,0 +1,79 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/thermal/qcom,pm8901-temp-alarm.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm PM8901 PMIC Temperature Alarm
> +
> +maintainers:
> +  - Herman van Hazendonk <github.com@xxxxxxxxxx>
> +
> +description: |
> +  PM8901 is a secondary PMIC paired with PM8058 on MSM8x60 family
> +  (MSM8260/MSM8660/APQ8060) platforms. It exposes an over-temperature
> +  alarm block at SSBI offset
> +  0x23 (CTRL) / 0x24 (PWM) with four selectable thresholds and three
> +  escalating stages. Unlike PM8058, there is no raw die-temperature
> +  ADC channel — the driver decodes the stage + threshold pair into a
> +  representative millicelsius value.

Don't describe the driver in the bindings.

> +
> +  Two PMIC-internal interrupts are exposed: a stage-transition alarm
> +  (TEMP_ALARM, PM8901 IRQ block 6 bit 4 == 52) and a hi-temp alarm
> +  (TEMP_HI_ALARM, block 6 bit 5 == 53).

I think, register definitions are too verbose for the bindings.

> +
> +  The driver registers a thermal-of sensor; board DTs declare trip
> +  points and a critical-trip action against it.

The same.

> +
> +properties:
> +  compatible:
> +    const: qcom,pm8901-temp-alarm
> +
> +  reg:
> +    description: SSBI offset of the temp-alarm CTRL register.
> +    maxItems: 1
> +
> +  interrupts:
> +    items:
> +      - description: Stage-transition alarm interrupt (TEMP_ALARM).
> +      - description: Hi-temperature alarm interrupt (TEMP_HI_ALARM).
> +
> +  interrupt-names:
> +    items:
> +      - const: alarm
> +      - const: hi-alarm
> +
> +  "#thermal-sensor-cells":
> +    const: 0
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - interrupt-names
> +  - "#thermal-sensor-cells"
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    ssbi {
> +      pmic {
> +        compatible = "qcom,pm8901";
> +        #interrupt-cells = <2>;
> +        interrupt-controller;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        pm8901_temp: temp-alarm@23 {
> +          compatible = "qcom,pm8901-temp-alarm";
> +          reg = <0x23>;
> +          interrupts = <52 IRQ_TYPE_EDGE_RISING>,
> +                       <53 IRQ_TYPE_EDGE_RISING>;
> +          interrupt-names = "alarm", "hi-alarm";
> +          #thermal-sensor-cells = <0>;
> +        };
> +      };
> +    };
> -- 
> 2.43.0
> 

-- 
With best wishes
Dmitry