Messages in this thread |  | | | From | Oliver Neukum <> | | Subject | Re: ehci-hcd affects hda speed | | Date | Wed, 16 Apr 2008 07:38:12 +0200 |
Am Dienstag, 15. April 2008 22:41:19 schrieb Lev A. Melnikovsky:
>
> On Wed, 16 Apr 2008 at 12:02am, Oliver Neukum wrote:
>
> ON> Am Dienstag, 15. April 2008 21:56:24 schrieb Lev A. Melnikovsky:
> ON> > The oddest peculiarity for me is the hysteretic difference between #1 and
> ON> > #3 states. I mean experimental data (hda throughput) depends not on the
> ON> > state (hardware/loaded modules), but on the path we followed.
> ON>
> ON> Did you compile with CONFIG_USB_SUSPEND?
>
> # CONFIG_USB_SUSPEND is not set
>
> Does this explain something?
EHCI should not scan an empty async. However this manufacturer
has shown a liberal attitude about conforming with specifications.
If the root hub is suspended, it can't do DMA. So it might help.
Regards
Oliver
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