On Mon, 2009-06-22 at 15:30 -0400, Duane Ellis wrote:
> All - I believe - I am not sure - that the primary benefit of 
> "libft2xxx" is as follows:
> 
> (a)   It is measurably faster.
> 
>     That just requires "work" to make it faster.
> 
> (b)   It works on more platforms, ie: Win7, WinVista, because drivers 
> exist for those platforms.
> 
>     This is tough/hard, nobody on this list is a "windows driver developer".
>     Grrr. Such is life.
> 
> (c)   Nobody was offering a universal "libusb" - type "INF" files for 
> windows.
> 
>     Looks like Freddie Chopin is working on that :-)  Perhaps - we could 
> have a "contrib" folder with a *binary* libusb0.sys file
>     and associated "INF" files that references *ALL* ftdi based dongles 
> - (The VID/PID list is in the source file...)
>     That *INF* file and matching SYS file should be deliverable with 
> OpenOCD.
> 
> (d) There is another choice -  "WinUSB"
> 
>     http://msdn.microsoft.com/en-us/library/aa476426.aspx
> 
> As I understand, it is a a multi-(windoze)-platform solution that 
> exposes the USB device, functionally in the same manor and style as 
> "libusb" does, ie: the ablity (1) to rd/wr endpoints, (2) send control 
> commands.
> 
> I believe there is the only open question that needs to be asked and 
> answered.
> 
> The MS-WinUSB driver - did not  *ship* with WinXP, but is available as a 
> "co-install" for WinXP.
> 
> As I understand (I have not confirmed, and I do not know all the details 
> of it), the driver and associated OS-libraries/headers are *PRESENT* on 
> Vista, and I presume Win7 (with appropriate dev tools installed), 
> therefore it functionally *SHIPS* with the operating system, and as such 
> it sould fall under the standard operating system component exception to 
> the GPL.
> 
> This solution is - by design - something that can be added to WinXP (the 
> co-install solution).  I think of it sort of like this: "The old system 
> only supplied a CDROM (read-only) driver" - later - new systems come 
> with CD-WRITER (and today, we have CD-RW) - the *new* os does not 
> require an upgrade, the *old* os has an upgrade path to make the 
> CD-WRITER (and now CD-RW) work.
> 
> I should - as a user of that old system - install the OS update - and be 
> able to make use of that GPL software.
> 
> All is not rosy and perfect, "WinUSB" would require an INF file that 
> *points* to the driver - much like the work that Freddy is working 
> towards with a universal libusb inf file
> 
> Agree?
> 
> -Duane.

This is a VERY interesting suggestion.

WunUSB *is* a system library, as it comes from the OS vendor and
provides general services for many devices, not just one subset of
devices. It is a General USB interface.

This should also have the advantage of being signed by microsoft so it
will install on all (current) versions of the windows operating systems.

The question I have is...

If we have an INF file pointing to a signed driver, does the INF/Driver
pair need to be signed, or is the signing just the authenticate the
driver CODE as being trusted?

If it is just the driver code, then I think this is the most stable long
term solution above all.

Now assuming libftdi interfaces to a USB library that could mean that
the 32/64 bit issues can be handled in winusb, since USB is just a frame
based communications pipe (byte stream)

Tom

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