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wdfdevicestopidle

frog981frog981 Member Posts: 2

I understand from the documentation that this call can't be made if the driver is not a power policy owner. What (technique) is the equivalent of this call for a rawpdo to prevent
the parent device from entering idle while its processing an ioctl? The parent device is also not a power policy owner

Comments

  • Doron_HolanDoron_Holan Member - All Emails Posts: 10,584

    You left out a little bit of relevant information related to roles and state. What type of driver are you writing? From your description, it is a filter driver that enumerates a raw PDO. Is that correct? What is the device class that the filter is installed in? Usually the pattern enumerating a raw PDO from a filter is due to the inability to open the filter directly, where the keyboard and mouse class are the usual classes where a filter does this.

    d
  • frog981frog981 Member Posts: 2

    Hi Doron, yes, fd and its a usb device.

  • Doron_HolanDoron_Holan Member - All Emails Posts: 10,584

    "it is a usb device" is not an answer to the "what device class is the filter driver installed in?" What device class is your filter installed in? To help you out, what does the Class= line look like in the [Version] section of your filter's INF?

    d
  • Muthu_KumarMuthu_Kumar Member Posts: 31

    It is a custom sensor device and we don't own the function driver but have access to device spec etc.

  • Doron_HolanDoron_Holan Member - All Emails Posts: 10,584

    Is it a custom function driver or inbox? Regardless, you need to poke the function driver to power up the device/keep it from idling. Typically this means sending io to the function driver to perform the operation you want to execute. The function driver will then power up (if idle) to process the IO request.

    d
  • Muthu_KumarMuthu_Kumar Member Posts: 31

    Makes sense. Will give it a try. Thx

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