RE: USB Driver uhci.c legacy mode

[D, Eshwar (Eshwar)]

> -----Original Message-----
> From: address@hidden 
> [mailto: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...

Regards
Eshwar
> >   
> >> -----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
> >
> >   
> 
> 
> --
> Regards
> Vladimir 'φ-coder/phcoder' Serbinenko
> 
> 
>