hi alan

2015-01-19 1:06 GMT+08:00 Alan Stern <[email protected]>:
> On Sun, 18 Jan 2015, Chechun Kuo wrote:
>
>> for some platform ehci controller, it is possible there is no port power 
>> control capability in the root hub.
>> And we add port power control determination when getting root hub port 
>> status.
>
> Why do you need to do this?  Doesn't the current code always give the
> right result?

My host controller doesn't support PPC, and the PORT_POWER bit will
not be one even when device is powered up.
After I checking the ehci spec, it should be HW's issue, since spec
say PP should be one even when PPC is zero.
Sorry to make you confuse ^^
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