Re: [avrdude-dev] Build error with SVN trunk

[Joerg Wunsch]

As Hannes Weisbach wrote:

> > (I can take over the
> > testing part for that if you want, I've got an FT2232D board and an
> > FT232H sample module to try with.)

> Thanks for the offer. Does it include libusb-1.0 with libusb-compat
> and libftdi-0.x too? ;)

Depends on how you'd recognize FreeBSD's implementation: it's an
OS-supplied libusb that provides three different APIs: 0.1
compatibility, 1.0 compatibility, and native FreeBSD's v2 API.

Yes, the offer to test libftdi-0.20 is meant to work an that platform.

I can also test Solaris/sparc64, which only has libusb-0.1 (to the
best of my knowledge).  I haven't tried compiling libftdi there
though.

> libusb-1.0 is considered finished and stable.

Except see above, Solaris doesn't have it.

Also, I'm not sure whether anyone so far tested all this on Win32
against libusb-1.0.  All I've done so far was against the old
libusb-win32 0.1, but a 1.x version is available now (unlike a couple
of years ago).

> To use libusb-1.0 one has to use libftdi-1.x.

No, one can use libusb-1.0 completely without libftdi. ;-)

I think you meant it the other way: libftdi 1.x requires libusb 1.x.

> lib{usb,ftdi}-1.0 also feature asynchronous I/O and it is my
> understanding that with this feature the ftdi_syncbb programmer will
> be able to work without threading, so we loose one dependency
> (pthreads) with "just" an update.

That's a point, though the only constellation right now that would
really benefit from it is MinGW32 builds.  They are currently the only
platform not offering pthreads.

I'm not opposed to have the code for lib{usb,ftdi}-1.x in, I'd just
like to not see the ability to also work with older versions go away
that quickly (within their limitations, of course).  Sometimes people
simply use older, not very well equipped machines for these tasks,
where they have troubles updating everything to the latest and
greatest bits.  I think it's a nice feature of AVRDUDE of being able
to use whatever "is just there".

> Last but not least, FreeBSD has a libusb-1.0 compatible
> implementation. I don't know why they are not providing libftdi-1.x.

libusb is OS-supplied code there.  libftdi is 3rd-party software which
is simply much less frequently maintained sometimes.  The overall rule
for FreeBSD is often to better be stable rather than bleeding edge.

Before FreeBSD 8.x, they had a completely different USB
implementation.  For this one, they were just using the public
libusb-0.1 implementation, with no chance for a libusb-1.0.  I still
have one old machine where I can test this constellation, too.  Of
course, it's not expected that all the recent FTDI stuff will work
there, but at least proven bits like support for JTAGICEmkII and
AVRISPmkII over libusb-0.1 are supposed to work even in those ancient
environments.
-- 
cheers, Joerg               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/
Never trust an operating system you don't have sources for. ;-)