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STM32 as bus-powered USB device: how to negotiate more power?

Question asked by CaCO3.CaCO3 on Jan 8, 2016
Latest reply on Jan 10, 2016 by markt
According to, a vbus powered USB device (slave) can only pull more than 100 mA after it negotiated with the host (e.g. PC):
"High power bus powered functions will draw all its power from the bus and cannot draw more than one unit load until it has been configured, after which it can then drain 5 unit loads (500mA Max) provided it asked for this in its descriptor."

How does the STM32Cube USB device library do this? I can not find any parameter in the Configuration descriptor.
Above page states this:
"A USB device specifies its power consumption expressed in 2mA units in the configuration descriptor".

The UM1734 - User Manual - STM32Cube USB device library does not state anything about this.