Re: Power Management and USB

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For the USB Host Controller Driver, it does not much for the power management.
No POWER IOCTL is supported and for PowerUp/Down handler it just simplify stop/reinitialize the BUS or Suspend/Resume the HCD if HCD_SUSPEND_RESUEME capability is supported.
For power control, you may implement your own PowerUp/Down handler in your PDD layer (HcdPdd_PowerXXX).

For USB Function and OTG as they did consider more about the Power IOCTL and implmented (USBOTG), rely on Power IOCTL to control the power could be a better idea.

"TechNick" <nickmachielse@xxxxxxxxx> wrote in message news:6e9cd169-7c9f-4f8d-b1b1-2b3372d6779d@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
On 27 feb, 11:39, Fabrice MOUSSET <fabrice.mous...@xxxxxxxxxxx> wrote:
Hi all,
I am building a WinCE 6.00 BSP for a custom board.
For this BSP I need to cut USBs, UARTs, Ethernet and some GPIO under
some circumstances.

To do that, I have create my own Power Manager based on the PM public
driver, I create a new Power State.
For the GPIOs, UARTs and the Ethernet there is no problem, I found all
the help I need in MSDN to add Power Management support for does drivers.

But now my problem is with the USB drivers, how does Windows CE 6.00
Power management with:
* USB host drivers ?
* USB devices drivers ?
* USB OTG drivers ?

Can someone gives me hints or pointers to the documentation?
I think it is only a question of registry keys but I don't really
know/understand which keys I have to step and/or modify.

Thanks in advance for any help

Best regards

Fabrice Mousset

Hi,

When you only need to shut down and power up your driver before
shutting down / powering up your system it is enough to use the
XXX_PowerUp and XXX_PowerDown functions in your USB driver.
If you need to use specific power states ( D0 - D4 ) in your USB
drivers you need to register your USB driver to the Power Manager
using an IClass value in the registry. ( try to find some examples in
your reginit.reg file ).
After this you should add the IOCTL_POWER_CAPABILITIES to your
XXX_IOControl interface.

See also:
http://groups.google.com/group/microsoft.public.windowsce.platbuilder/browse_thread/thread/b77885b3ade38ace/bf9d16fadd492c98?hl=en&lnk=gst&q=IOCTL_POWER_SET#bf9d16fadd492c98

.

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