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| author | Alan Stern <stern@rowland.harvard.edu> | 2007-01-16 19:59:45 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2007-02-08 02:44:37 +0300 |
| commit | 57e06c11372eccf5acebdd4664eb025fee76c561 (patch) | |
| tree | a792559056735005ce7037196509fb151d3c3bc5 /drivers/acpi/system.c | |
| parent | 625b5c9a0069ef1b61feb3ce599b39f1b04b5666 (diff) | |
| download | linux-57e06c11372eccf5acebdd4664eb025fee76c561.tar.xz | |
EHCI: force high-speed devices to run at full speed
This patch (as710) adds a sysfs class-device attribute file named
"companion" for EHCI controllers. The file contains a list of port
numbers that are dedicated to the companion controller; by writing a
port number to the file the user can force a high-speed device
attached directly to the computer to run at full speed. (As far as I
know it is not possible to do this for a device attached to an
external hub.) A port is removed from the file by writing the
negative of its port number.
Several users have asked for this facility and it seems like a useful
thing to have. Every now and then one runs across a device which
behaves much better at full speed than at high speed.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/acpi/system.c')
0 files changed, 0 insertions, 0 deletions