Re: USB Host Controller's Lower Power mode in Suspend State Sequence

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From: David Liao \(MS\) (davli_at_online.microsoft.com)
Date: 10/06/04 

Date: Wed, 6 Oct 2004 14:32:40 -0700

I don't think this is going to work because after removing Clock from USB
HC, you need reset USB HC after reableing clock. THis mean you need reset
USB HC driver (ohci2.dll).
You may want to try this to save the power.
[HKEY_LOCAL_MACHINE\Drivers\BuiltIn\OHCI]
    "InterfaceType"=dword:0 ; Internal
    "Prefix"="HCD"
    "Dll"="ohci2.dll"
    "Index"=dword:1
    "Order"=dword:1
    "Irq"=dword:3
    "SysIntr"=dword:11 ; (SYSINTR_FIRMWARE+1)
    "MemBase"=dword:4C000000
    "MemLen"=dword:1000
    "UseExistingSettings"=dword:0
;;<----- add following line make HC suspend when there is no device
attached.
   "HcdCapability"=dword:4 ;HCD_SUSPEND_ON_REQUEST

David Liao

"bird" <msnews.microsoft.com> wrote in message
news:uZBVpItqEHA.3896@TK2MSFTNGP15.phx.gbl...
> Dear All:
> I implement the function that forUSB Host Controller enter Lower Power
> mode
> in Suspend State when the CPU is entered Sleep,I following the sequence
> descript in the PXA27X spec.(20.7.4.2)
> But how can I return to active that issued when the CPU wakeup from Sleep
> ?!
> When I start the clock the HC always stay in reset state,the Spec only
> said S/W wait the usbportresume interrupt but there is no any interrupt
> will
> be issued...
>
>
>

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