The Fairphone 2 has an USB expansion port behind the back cover, near the battery (found very few info, pinout here ).
It is not supported yet in the kernel (nothing is detected when I plug a peripheral).

What I tried

I have tried to modify the device tree, recompile the kernel and flash it but I cannot get it to work.
My fork is available here. I went from the branch qcom-msm8974-6.11.y and created a branch qcom-msm8974-6.11-wip where I added two tags (v6.11.5-msm8974 and v6.11.6-msm8974) to test my changes.
I then updated the APKBUILD of linux-postmarketos-qcom-msm8974 to retrieve the tar from my fork with my tag, then used pmbootstrap build --force linux-postmarketos-qcom-msm8974, then install & flash.
My modifications are correctly applied to the kernel, but the USB still doesn't work, so I suppose my modifications are wrong :

In /arch/arm/boot/dts/qcom/qcom-msm8974pro-fairphone-fp2.dts

&usb {
	status = "okay";

	phys = <&usb_hs1_phy>, <&usb_hs2_phy>;
	phy-select = <&tcsr 0xb000 0>;
	extcon = <&smbb>, <&usb_id>;
	vbus-supply = <&chg_otg>;

	hnp-disable;
	srp-disable;
	adp-disable;
};

&usb_hs1_phy {
	status = "okay";

	v1p8-supply = <&pm8941_l6>;
	v3p3-supply = <&pm8941_l24>;

	extcon = <&smbb>;
	qcom,init-seq = /bits/ 8 <0x1 0x64>;
};

&usb_hs2_phy {
	status = "okay";

	v1p8-supply = <&pm8941_l6>;
	v3p3-supply = <&pm8941_l24>;

	extcon = <&smbb>;
	qcom,init-seq = /bits/ 8 <0x1 0x64>;
};

Have you already tried to modify this, or do you have any insight about what I am doing wrong ?