Re: [PATCH v3 2/4] dt-bindings: arm: mediatek: Add new bindings of MediaTek frequency hopping

From: AngeloGioacchino Del Regno
Date: Thu Sep 29 2022 - 09:08:01 EST


Il 29/09/22 13:46, Johnson Wang ha scritto:
Add the new binding documentation for MediaTek frequency hopping
and spread spectrum clocking control.

Co-developed-by: Edward-JW Yang <edward-jw.yang@xxxxxxxxxxxx>
Signed-off-by: Edward-JW Yang <edward-jw.yang@xxxxxxxxxxxx>
Signed-off-by: Johnson Wang <johnson.wang@xxxxxxxxxxxx>
---
.../arm/mediatek/mediatek,mt8186-fhctl.yaml | 53 +++++++++++++++++++
1 file changed, 53 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml

diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml
new file mode 100644
index 000000000000..258dff7ce6bc
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/mediatek/mediatek,mt8186-fhctl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek frequency hopping and spread spectrum clocking control
+
+maintainers:
+ - Edward-JW Yang <edward-jw.yang@xxxxxxxxxxxx>
+
+description: |
+ Frequency hopping control (FHCTL) is a piece of hardware that control
+ some PLLs to adopt "hopping" mechanism to adjust their frequency.
+ Spread spectrum clocking (SSC) is another function provided by this hardware.
+
+properties:
+ compatible:
+ const: mediatek,mt8186-fhctl
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ description: Phandles of the PLL with FHCTL hardware capability.
+ minItems: 1
+ maxItems: 30
+
+ mediatek,hopping-ssc-percent:
+ description: The percentage of spread spectrum clocking for one PLL.
+ minItems: 1
+ maxItems: 30
+ items:
+ default: 0
+ minimum: 0
+ maximum: 8
+
+required:
+ - compatible
+ - reg
+ - clocks
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/mt8186-clk.h>
+ fhctl: fhctl@1000ce00 {
+ compatible = "mediatek,mt8186-fhctl";
+ reg = <0x1000c000 0xe00>;
+ clocks = <&apmixedsys CLK_APMIXED_MSDCPLL>;
+ mediatek,hopping-ssc-percent = <3>;
+ };


.... a more realistic example:

#include <dt-bindings/clock/mt8186-clk.h>

soc {
#address-cells = <2>;
#size-cells = <2>;

fhctl: fhctl@1000ce00 {
compatible = "mediatek,mt8186-fhctl";
reg = <0 0x1000c000 0 0xe00>;
clocks = <&apmixedsys CLK_APMIXED_MSDCPLL>;
mediatek,hopping-ssc-percent = <3>;
};
};

After which...

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>