Enumerating USB devices in the Bootloader

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Hi,

We are using the USB mass storage gadget driver in Linux and
everything is working fairly well but sometimes we are finding that we
are exceeding the 100mA limit (which I think is the default the host
will provide) before Linux has had a change to enumerate the USB
device at which point we ask for 500mA.  We have tried to reduce the
power by ensuring all clocks are turned off, devices not used disabled
etc but can't seem to satisfy the 100mA limit.  We were thinking that
maybe we could enumerate the USB device during U-Boot at which point
we know we are under the 100mA limit.  Does anyone know a reason why
this would not work? would at some point from U-Boot enumerating a new
bMaxPower would the connection be reset and drop back to 100mA during
the kernel startup? Are there any considerations that we would need to
take care of in the kernel for this to work?

Many Thanks,
Martin.



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