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
| |