Théo Lebrun [off-list ref] writes:

[...]

Some TI platforms cannot tell, before going to suspend, if their USB
controller will reset. Suspend behavior is defined by (at least) two
features:

 - Power domains. See arch/arm64/boot/dts/ti/k3-j7200-main.dtsi:

   usbss0: cdns-usb@4104000 {
      compatible = "ti,j7200-usb", "ti,j721e-usb";
      // ...
      power-domains = <&k3_pds 288 TI_SCI_PD_EXCLUSIVE>;
      // ...
   };

   This `power-domains` property implies that even s2idle will reset
   the controller.

minor but important clarification: not *will* reset, but *might* reset the controller.

Kevin