KMDF Usb Multiple Configuration

siddu

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Mar 26, 2008, 8:36:03 AM3/26/08

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hi all,

I am writing a driver for USB to Serial device in KMDF, which has 2
configurations. After selecting 1 configuration and downloading the firmware,
i am not able to switch to 2 configuration. I want to know whether KMDF
supports multiple configurations and how to select the required configuration.

thank you,
siddu.

Doron Holan [MSFT]

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Mar 26, 2008, 4:36:04 PM3/26/08

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no, WDFUSBDEVICE does not supoprt multiple configurations. you can do this
yourself with WDFIOTARGETs if you want. why not expose the firmware updater
as an interface on a single configuration and just consume this interface
internally in the driver to update the device?

d

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"siddu" <siddu...@gmail.com> wrote in message
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chris.a...@gmail.com

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Mar 27, 2008, 10:25:36 AM3/27/08

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I would just use a separate PID (and USB configuration #0) for the
"firmware loaded" configuration.

siddu

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Mar 28, 2008, 7:59:01 AM3/28/08

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Hi Doron,
Thanks for the reply.Can u plz explain how to do this using WDFIOTARGET.
As the device has 2 configurations, after getting 1st configuration we
download the firmware and the firmware will activate the 2nd configuration.
The firmware cannot be modified so plz tell some other way.

thank you,
siddu.

chris.a...@gmail.com

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Mar 29, 2008, 10:57:29 AM3/29/08

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On Mar 28, 6:59 am, siddu <siddu.k...@gmail.com> wrote:

> Thanks for the reply.Can u plz explain how to do this using WDFIOTARGET.
> As the device has 2 configurations, after getting 1st configuration we
> download the firmware and the firmware will activate the 2nd configuration.
> The firmware cannot be modified so plz tell some other way.

The KMDF USB DDI's are quite handy, especially the continuous reader.
As such, I don't think you want to lose access to them this easily.
I'll offer a different solution: create a lower filter to your KMDF
function driver that masks/handles the second configuration of your
device.

The upper edge of the filter will present the device in configuration
#0, whether it is in configuration #0 or not. The lower edge will
handle selecting the alternate configuration using manually created
URBs.

Tim Roberts

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Mar 29, 2008, 7:37:19 PM3/29/08

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siddu <siddu...@gmail.com> wrote:
>
>Hi Doron,
> Thanks for the reply.Can u plz explain how to do this using WDFIOTARGET.
>As the device has 2 configurations, after getting 1st configuration we
>download the firmware and the firmware will activate the 2nd configuration.
>The firmware cannot be modified so plz tell some other way.

The firmware can always be modified. In this case, your hardware designers
have made a very poor implementation choice, without first considering the
operating environment they would be selling into. The proper fix is to
correct the design so that it works cooperatively in their target market.
--
Tim Roberts, ti...@probo.com
Providenza & Boekelheide, Inc.

chris.a...@gmail.com

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Mar 30, 2008, 9:32:14 PM3/30/08

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On Mar 29, 6:37 pm, Tim Roberts <t...@probo.com> wrote:

> The firmware can always be modified. In this case, your hardware designers
> have made a very poor implementation choice, without first considering the
> operating environment they would be selling into. The proper fix is to
> correct the design so that it works cooperatively in their target market.

You can't be serious.

Tim Roberts

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Mar 31, 2008, 10:54:50 PM3/31/08

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chris.a...@gmail.com wrote:

Why not? If you expect to sell a device into the Windows market, you
better make darned sure that your device plays nicely with Windows, even if
you do something that is valid by the spec.

chris.a...@gmail.com

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Apr 1, 2008, 8:03:15 AM4/1/08

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On Mar 31, 9:54 pm, Tim Roberts <t...@probo.com> wrote:

> Why not? If you expect to sell a device into the Windows market, you
> better make darned sure that your device plays nicely with Windows, even if
> you do something that is valid by the spec.

Well, I'm just saying, I have a feeling you've been around long enough
to know that no, the firmware can't "always" be changed (what if this
device is in the field already?) and that driver writers are often
asked to work around hardware problems..