Greetings, my friends. As you may have memorized by now, I have a
Powerbook G3 Wallstreet series, which comes with no USB. My local SF
Bay Area Macintosh dealer, www.computerware.com, has two USB adapters
for me.
One is at http://www.macally.com/new/usb/newuh276.html. The second
one is from Orange Micro, to which I can't find a URL so far.
Do you guys have any idea how feasible it would be to support either
one under LinuxPPC?
I realize that there is a lot of unstable work right now integrating
pcmcia support into the standard kernel tree. Hopefully Linus's laptop
usage will propel that as it did with USB ;) But I don't know how
well the two peripheral protocols have converged, considering that I'm
hearing from people on this list whose machines halt when they simply
insert a card of an arbitrary type.
Shall I buy one now, and cheer you guys on until it works?
I've said it before, and I'll say it again. I want my Powerbook to
rock, and that requires Linux support. So, if any of you want to take
on support for any given item, just let me know what would motivate
you, and I'll see what I can do. I'm not an employer; just a highly
motivated and motivatable non-programming citizen. I could send
someone one of these USB cards, if they like. For free!
But I'm working on that non-programming part. I just spent $200 on
Apple literature, from corporate tales to Apple // hacking. I read
"Inside the Apple //gs" cover to cover in one evening, and understood
most of it except some specific device driver (usually assembly)
techniques. But, back then, almost everything was a device driver.
Anyhow, lemme know.
=====
"Don't expect your own messiah; this neverworld which you desire is
only in your mind." -- http://www.dreamtheater.net/songb4.htm#IV5
** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/
At 12:15 AM -0800 2/20/00, Dan Bethe wrote:
Greetings, my friends. As you may have memorized by now, I have a
Powerbook G3 Wallstreet series, which comes with no USB. My local SF
Bay Area Macintosh dealer, www.computerware.com, has two USB adapters
for me.
One is at http://www.macally.com/new/usb/newuh276.html. The second
one is from Orange Micro, to which I can't find a URL so far.
Do you guys have any idea how feasible it would be to support either
one under LinuxPPC?
Very feasible.
I realize that there is a lot of unstable work right now integrating
pcmcia support into the standard kernel tree. Hopefully Linus's laptop
usage will propel that as it did with USB ;) But I don't know how
well the two peripheral protocols have converged, considering that I'm
hearing from people on this list whose machines halt when they simply
insert a card of an arbitrary type.
PCMCIA USB adapters are CardBus devices. CardBus is repackaged
hot-swap PCI. So what's actually in the card is a standard PCI USB
OHCI controller.
The USB drivers already support OHCI PCI USB controllers. There are
only two types anyways, UHCI and OHCI (these are standards for how
the registers work so that the same drivers work across multiple
vendor's USB chips). For various reasons Apple supports only OHCI
under MacOS, so all USB interfaces sold for Macs are OHCI by
definition. This has trickled down to Linux, as last I heard nobody
had even bothered making the Linux UHCI driver work on PPC. (You
wouldn't want it anyways -- it's my belief, based on reading the USB
development list, that UHCI is inferior. They're having a lot more
problems getting UHCI to work right, and there is this evil thing
called "bandwidth reclamation" which they have to do to get good
performance, at the cost of undesirable PCI bus hogging.)
Anyways, the only conceivable difficulty is that when you plug in the
card, the OHCI driver won't get a crack at owning it. This is
probably what would happen on 2.2.x + PCMCIA-CS 3.0.x, because in the
old scheme of things the PCMCIA package has its own drivers for
CardBus and PC Cards.
In 2.3.x, Linus has moved a lot of the PCMCIA stuff into the kernel,
and CardBus cards are now treated as a class of hot swap PCI devices
handled by the standard kernel PCI code. This means that under 2.3.x
it should "just work", barring bugs, of which there are many.
Tim Seufert
** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/