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arm64: dts: qcom: sa8775p-ride: move the reset-gpios property of the PHY

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Device-tree bindings for MDIO define per-PHY reset-gpios as well as a
global reset-gpios property at the MDIO node level which controls all
devices on the bus. The latter is most likely a workaround for the
chicken-and-egg problem where we cannot read the ID of the PHY before
bringing it out of reset but we cannot bring it out of reset until we've
read its ID.

I have proposed a comprehensive solution for this problem in 2020 but it
never got upstream. We do however have workaround in place which allows
us to hard-code the PHY id in the compatible property, thus skipping the
ID scanning.

Let's make the device-tree for sa8775p-ride slightly more correct by
moving the reset-gpios property to the PHY node with its ID put into the
PHY node's compatible.

Link: https://lore.kernel.org/all/20200622093744.13685-1-brgl@bgdev.pl/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Tested-by: Andrew Halaney <ahalaney@redhat.com>
Link: https://lore.kernel.org/r/20230810080909.6259-5-brgl@bgdev.pl
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
This commit is contained in:
Bartosz Golaszewski
2023-08-10 10:09:04 +02:00
committed by Bjorn Andersson
parent 6ca89cc680
commit 5255901fb2
1 changed files with 4 additions and 4 deletions
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8
arch/arm64/boot/dts/qcom/sa8775p-ride.dts
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@@ -279,13 +279,13 @@ mdio {
#address-cells = <1>;
#size-cells = <0>;
reset-gpios = <&pmm8654au_2_gpios 8 GPIO_ACTIVE_LOW>;
reset-delay-us = <11000>;
reset-post-delay-us = <70000>;
sgmii_phy: phy@8 {
compatible = "ethernet-phy-id0141.0dd4";
reg = <0x8>;
device_type = "ethernet-phy";
reset-gpios = <&pmm8654au_2_gpios 8 GPIO_ACTIVE_LOW>;
reset-assert-us = <11000>;
reset-deassert-us = <70000>;
};
};