Re: [PATCH v7 2/6] dt-bindings: thermal: Add binding document for LVTS thermal controllers

AngeloGioacchino Del Regno
2022-05-26T12:58:19Z

Il 24/05/22 17:25, Alexandre Bailon ha scritto:
> This patch adds binding document for mt8192 and mt8195 thermal
> controllers.
>
> Signed-off-by: Alexandre Bailon <abailon@baylibre.com>
> ---
> .../thermal/mediatek,mt8192-lvts.yaml | 81 +++++++++++++++++++
> 1 file changed, 81 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/thermal/mediatek,mt8192-lvts.yaml
>
> diff --git a/Documentation/devicetree/bindings/thermal/mediatek,mt8192-lvts.yaml b/Documentation/devicetree/bindings/thermal/mediatek,mt8192-lvts.yaml
> new file mode 100644
> index 000000000000..914c877d1f2f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/mediatek,mt8192-lvts.yaml
> @@ -0,0 +1,81 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/thermal/mediatek,mt8192-lvts.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: MediaTek SoC LVTS thermal controller
> +
> +maintainers:
> + - Yu-Chia Chang <ethan.chang@mediatek.com>
> + - Ben Tseng <ben.tseng@mediatek.com>
> +
> +allOf:
> + - $ref: thermal-sensor.yaml#
> + - $ref: /nvmem/nvmem-consumer.yaml#
> +
> +properties:
> + compatible:
> + enum:
> + - mediatek,mt8192-lvts
> + - mediatek,mt8195-lvts
> +
> + reg:
> + minItems: 2
> + maxItems: 4
> +
> + interrupts:
> + maxItems: 2
> +
> + clocks:
> + maxItems: 1
> +
> + "#thermal-sensor-cells":
> + const: 1
> +
> + nvmem-cells:
> + maxItems: 2
> + description: Calibration data for thermal sensors
> +
> + nvmem-cell-names:
> + items:
> + - const: e_data1
> + - const: e_data2

From what I understand, each nvmem cell has calibration data for each thermal
sensor, so let's use some more descriptive names...
some ideas: "lvts1-calib" "lvts1-cal" "calib1".

Also, I think that the best option is to register one driver instance for each
hardware instance, meaning that you should have only one reg, only one nvmem-cell,
only one reset, only one interrupt. This makes it possible to have as many
LVTS instances as possible without any code adjustments in the future.

An example for MT8195:

thermal-sensor@1100b000 {
compatible = "mediatek,mt8195-lvts";
reg = <0 0x1100b000 0 0x1000>;
interrupts = <GIC_SPI 169 IRQ_TYPE_LEVEL_HIGH 0>;
#thermal-sensor-cells = <1>;
clocks = <&infracfg_ao CLK_INFRA_AO_THERM>;
nvmem-cells = <&lvts_e_data1>;
nvmem-cell-names = "calibration";

/* is this a reset for lvts1? */
resets = <&infracfg_ao MT8195_INFRA_RST0_THERM_CTRL_SWRST>;
};

thermal-sensor@11278000 {
compatible = "mediatek,mt8195-lvts";
reg = <0 0x11278000 0 0x1000>;
interrupts = <GIC_SPI 170 IRQ_TYPE_LEVEL_HIGH 0>;
#thermal-sensor-cells = <1>;
clocks = <&infracfg_ao CLK_INFRA_AO_THERM>;
nvmem-cells = <&lvts_e_data2>;
nvmem-cell-names = "calibration";

/* is this a reset for lvts2? */
resets = <&infracfg_ao MT8195_INFRA_RST4_THERM_CTRL_MCU_SWRST>;
};

In the future, a new MediaTek SoC may simply define more nodes..... :-)

> +
> + resets:
> + $ref: /schemas/types.yaml#/definitions/phandle-array
> +
> +
> +required:
> + - '#thermal-sensor-cells'
> + - compatible
> + - reg
> + - interrupts
> + - clocks
> + - nvmem-cells
> + - nvmem-cell-names
> + - resets
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/thermal/thermal.h>
> + #include <dt-bindings/interrupt-controller/arm-gic.h>
> + #include <dt-bindings/clock/mt8195-clk.h>
> + #include <dt-bindings/reset/mt8195-resets.h>
> +
> + lvts: lvts@1100b000 {

Please use generic names: this should be thermal-sensor@1100b000

> + compatible = "mediatek,mt8195-lvts";
> + #thermal-sensor-cells = <1>;
> + reg = <0 0x1100b000 0 0x1000>,
> + <0 0x11278000 0 0x1000>;
> + interrupts = <GIC_SPI 169 IRQ_TYPE_LEVEL_HIGH 0>,
> + <GIC_SPI 170 IRQ_TYPE_LEVEL_HIGH 0>;
> + clocks = <&infracfg_ao CLK_INFRA_AO_THERM>;
> + resets = <&infracfg_ao MT8195_INFRA_RST0_THERM_CTRL_SWRST>,
> + <&infracfg_ao MT8195_INFRA_RST4_THERM_CTRL_MCU_SWRST>;
> + nvmem-cells = <&lvts_e_data1 &lvts_e_data2>;
> + nvmem-cell-names = "e_data1","e_data2";
> + };
> +...