filter driver

NTDEV
1

i wrote a nothingdo filter driver above usb hub. (GUID_DEVINTERFACE_USB_HUB)
used addfilter sample to install it as upper filter driver on \device\usbpdo-3

it gets called - with lot of pnp irps.

when i insert a usb device, it comes under this hub only but filter driver doesnt show any activity??

2

xxxxx@gmail.com wrote:

i wrote a nothingdo filter driver above usb hub. (GUID_DEVINTERFACE_USB_HUB)
used addfilter sample to install it as upper filter driver on \device\usbpdo-3

it gets called - with lot of pnp irps.

when i insert a usb device, it comes under this hub only but filter driver doesnt show any activity??

What kind of device was it? Was there a driver for it already? Did you
see PnP IRPs when you plugged in the new device?

–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.

3

Each usb device is going to be a child device of the hub it is connected to,
so unless you are also filtering the child devices you won’t see any
activity for those devices on the hub device.

windbg !devnode might help clarify this situation for you.

Mark Roddy

On Tue, Jun 1, 2010 at 10:04 AM, wrote:

> i wrote a nothingdo filter driver above usb hub.
> (GUID_DEVINTERFACE_USB_HUB)
> used addfilter sample to install it as upper filter driver on
> \device\usbpdo-3
>
> it gets called - with lot of pnp irps.
>
>
> when i insert a usb device, it comes under this hub only but filter driver
> doesnt show any activity??
>
> —
> NTDEV is sponsored by OSR
>
> For our schedule of WDF, WDM, debugging and other seminars visit:
> http://www.osr.com/seminars
>
> To unsubscribe, visit the List Server section of OSR Online at
> http://www.osronline.com/page.cfm?name=ListServer
>

4

“What kind of device was it? Was there a driver for it already? Did you
see PnP IRPs when you plugged in the new device?”

– it was a pen drive.

– yes driver was there and it works also.

– but when i plug it - no pnp irps??

“Each usb device is going to be a child device of the hub it is connected to,
so unless you are also filtering the child devices you won’t see any
activity for those devices on the hub device.” - yes- but i guess for creating a child device, hub should get some PnP Irps.