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From: Christer Weinigel <christer@weinigel.se>
To: grub-devel@gnu.org
Subject: EHCI driver
Date: Tue, 29 May 2012 11:07:56 +0200	[thread overview]
Message-ID: <4FC491EC.8010808@weinigel.se> (raw)

Hi list,

the EHCI driver in GRUB has some known problems with low-speed transfers
and split transactions [1].  On older machines this is not a big problem
since it's possible to connect low speed devices such a USB keyboard
directly to a port and use the UHCI driver instead.  But modern Intel
chipsets do not have a UHCI companion controller any more, they only
have a EHCI controller with a normal USB 2.0 rate matching hub
permanently connected to the EHCI port inside the chipset.

Has anybody had time to look any more at the EHCI driver?  Any ideas for
how to fix this?

  /Christer

[1] http://lists.gnu.org/archive/html/grub-devel/2011-10/msg00007.html


-- 
Have laptop, will travel.  I'm a consultant looking for interesting
jobs anywhere in the world.  I'm an experienced software engineer with
a solid understanding of hardware.  Specialties: Linux, device
drivers and embedded systems in general.  Find me at www.weinigel.se.


             reply	other threads:[~2012-05-29 16:19 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-29  9:07 Christer Weinigel [this message]
2012-05-29 22:46 ` EHCI driver Aleš Nesrsta
2012-05-30  9:28   ` Christer Weinigel
2012-05-30 12:12     ` Christer Weinigel
2012-05-30 12:35       ` Vladimir 'φ-coder/phcoder' Serbinenko
2012-05-31  8:40         ` Christer Weinigel
2012-05-31 12:08       ` Vladimir 'φ-coder/phcoder' Serbinenko
2012-05-30 12:24   ` Vladimir 'φ-coder/phcoder' Serbinenko
2012-05-30 17:28     ` Aleš Nesrsta
2012-05-30 17:40       ` Vladimir 'φ-coder/phcoder' Serbinenko
2012-07-09  8:48 yanxiang fang
2012-07-16 22:16 ` Aleš Nesrsta
2012-07-17 18:20   ` Aleš Nesrsta
2012-07-17 23:18 yanxiang fang
2012-07-18 15:32 ` Aleš Nesrsta
2012-07-22 16:58   ` Vladimir 'φ-coder/phcoder' Serbinenko
2012-07-22 19:24     ` Aleš Nesrsta
2012-07-19  0:31 yanxiang fang

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