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RE: USB Driver uhci.c legacy mode
D, Eshwar (Eshwar)
RE: USB Driver uhci.c legacy mode
Tue, 3 Aug 2010 10:56:47 +0530
> -----Original Message-----
> From: address@hidden
] On Behalf Of Vladimir 'f-coder/phcoder' Serbinenko
> Sent: Sunday, August 01, 2010 9:11 PM
> To: address@hidden
> Subject: Re: USB Driver uhci.c legacy mode
> On 07/27/2010 06:54 AM, D, Eshwar (Eshwar) wrote:
> > HI,
> > I would like to contribute for EHCI driver.. Let me know
> if any space is available for me... By the way I already
> spoke to Ales & Vladimir...
> AFAIK nobody else is working on EHCI even if it's important.
> Unfortunately I can't give you write access to offical bzr
> both because of legal and technical reasons. I recommend
> creating an account at launchpad. Also I recommend sending
> early patches to ML even if they don't work so nobody gets an
> impression that you've just disappeared and so we can comment
> early on your code. Some mistakes may go unnoticed on some
> hardware but be fatal on some other hardware.
Thank you very much.... I will start working from today onwards...
> >> -----Original Message-----
> >> From: address@hidden
> >> [mailto:address@hidden
> >> ] On Behalf Of Aleš Nesrsta
> >> Sent: Saturday, July 24, 2010 11:45 PM
> >> To: The development of GNU GRUB
> >> Subject: Re: USB Driver uhci.c legacy mode
> >> Hi, I am sorry to be late with answer, unfortunately, I
> have few time
> >> during our school holidays...
> >> To Your questions, chronologically:
> >>> how would i surely know that grub usb driver would not
> work on this
> >>> platform?
> >> None of current USB drivers will work if Your PC is
> EHCI-only PC. One
> >> way how to find it I described before (via lspci).
> >> But You have to be sure You have properly set USB part in BIOS (or
> >> You should try all possible USB BIOS configurations etc. ...).
> >> Another way is for example to find detailed specification of Your
> >> laptop HW. I tried shortly to find something on Internet but there
> >> are specifications like "USB 2.0 compatible" etc.
> >> and the same specifications are often used also for
> controllers which
> >> includes OHCI/UHCI USB 1.0 too - so, I am not sure.
> >> Definitely You can find it by check of HCSPARAMS register of EHCI.
> >> According EHCI specification, this 32-bit register should be at
> >> USBBASE
> >> + 08h (USBBASE pointer should be in PCI configuration registers at
> >> + PCI
> >> base + 10h).
> >> Bits 15:12 of HCSPARAMS should be nonzero. If You find zero there,
> >> You have EHCI-only controller (without OHCI/UHCI companion
> >> controllers) in Your PC, i.e., Your USB controller is
> currently not
> >> directly supported by GRUB :-(
> >>> jonatan perry wrote:
> >>> i have another question regarding grub usb ehci support - is such
> >>> support under development? is such support are planned to
> >> be? what is
> >>> the current status?
> >> Hm, I am not the right person to answer these questions
> properly, I
> >> am not coordinator... Maybe Vladimir Serbinenko will answer it
> >> better.
> >> >From my point of view:
> >> - Development of EHCI is planned.
> >> - Current status of EHCI driver development - probably 0%.
> >> AFAIK, nobody is currently working on EHCI support. But I could be
> >> wrong and it can change at any time.
> >> I was asked some months ago by Vladimir, if I am
> interesting also in
> >> EHCI. I answered "no" originally - because I thought that all EHCI
> >> controllers have also companion OHCI/EHCI controllers and speed of
> >> USB
> >> 1.0/1.1 devices is not critical for GRUB (because it is "only"
> >> bootloader...).
> >> I changed point of view from some reasons short time ago.
> I wanted,
> >> at least, find why some devices are not working on my
> EHCI/UHCI port
> >> - it looks like problem is on powering of ports (but UHCI has no
> >> power control of its ports - or, at least, it is not
> written in UHCI
> >> specification...). I think that this problem is maybe somewhere in
> >> EHCI, so I want to start some experiments with EHCI.
> >> But:
> >> - GRUB USB development is currently focused on enhancement and
> >> debugging of current USB drivers and related code - for example
> >> hot-plugging and hub support. I want to help with these
> things first
> >> before doing something new (and generate new bugs...).
> >> - EHCI is different and more complex than OHCI/UHCI
> >> - it looks like I will too busy in next weeks/months. So, if EHCI
> >> support will depend only on me, it will take very long
> time... Maybe
> >> somebody else will start development of EHCI driver sooner
> (or maybe
> >> it is started?)...?
> >> With regards
> >> Ales
> >> _______________________________________________
> >> Grub-devel mailing list
> >> address@hidden
> >> http://lists.gnu.org/mailman/listinfo/grub-devel
> > _______________________________________________
> > Grub-devel mailing list
> > address@hidden
> > http://lists.gnu.org/mailman/listinfo/grub-devel
> Vladimir 'φ-coder/phcoder' Serbinenko