Seeedstudio ReComputer RK3576 - MiniPCIE

[boobypi]

Hello,

I just received my SeedStudio Recomputer RK3576 and I have a well working machine thanks to the armbian team using the debian Forky image.
I try to understand why i cannot connect a (usb) minipcie modem (already testing 1 year use with Radxa zero 3 W), all usb ports not working anymore!

There is a strange note on schematic pdf : 

If the PCIe1 or SATA1 function of Combo PHY1 is
selected, the USB3 OTG1 function cannot be used,
and even the USB2 PHY1 function cannot be used

But they also notice the support of usb link on this minipcie : 
 

LTE LoRa Module: Module:EC20/EC25
WM1302 SPI/USB Version
Zigbee: USB Version

  

 

The miniPCIe is connected on USBHUB_HOST3 <- USB HUB external chip -> USB2_HOST1 (RK3576 soc).
All USB phy fail, even USB PHY not related to this usb hub.
lsusb didn't show my usb modem, even if there no usb devices connected.

I bought this nice machine as my home router with internal 4G modem quectel EC200A-EU but at this time ,my plan fail.
The idle powerdraw with nvme onboard is under 2W and wifi sta active, Nice dietpi hardware!

Thanks for your input (how to make this minipcie working, disable usb port is a possible tradeoff for me)
Seb

[boobypi]

Maybe it's just relative to reset pin on the LTE modem, locking down all the shared USB BUS.

On the dts, we can activate LTE_RESET : 

&i2c4 {
	status = "okay";
	pinctrl-0 = <&i2c4m3_xfer>;

	gpio_xten: gpio_xten@21 {
		compatible = "nxp,pca9535";
		reg = <0x21>;
		gpio-controller;
		#gpio-cells = <2>;
		
		interrupt-controller;
		gpio-line-names =
		"MIPI_DPHY_CSI0_IO1"	,"USB_USB30_PWREN_H",
		"USB_HOST_PWREN_H"	,"BRD_ID_WP",
		"LTE_RESET"	,"P05",
		"P06"	,"LoRaWan_sx1262_CS",
		"USER_LED_R"	,"USER_LED_B",
		"USER_LED_G"	,"P13",
		"P14"	,"P15",
		"P16"	,"P17";
		
		gpio-line-offsets = <0>, <1>, <2>, <3>, <4>, <5>, <6>, <7>, <8>, <9>, <10>, <11>, <12>, <13>, <14>, <15>;
	};

 

On the LTE modem manual, reset is active when LTE_RESET is low, and pullup to vcc in normal operation.

If LTE_RESET stay low with onboard modem connected, LTE modem may lock all USB ports.
How can I define LTE_RESET to 1 at the boot?