On Fri, 5 Sep 2008, Vitaly Bordug wrote: > I've started looking this way. Sorry, but this approach is a little bit > fragile, and unreliable. > > First, it just did not work out in case of usb2 hub with memory stick > and keybord plugged - OHCI did not suspend, ehci is hosed and we're > happily using hi-speed device on full-speed:
> Secondly, we may *not* rely on the fact, that OHCI will always have the > same suspend policy. Even kicking the code up to the shape when it will > automagically suspend in proper timing to get the HW issue around, we > cannot be sure that it will persist along kernel lifecycle, and won't > require concerned people to kick suspend timings back to the working > state subsequently each rc release. > > Thirdly, PM is disabled by Kconfig explicitly in case of 44x. Reasoning > is not clear at the moment, but I believe that isn't there just in case. I assume that's the reason the suggested approach failed. > > What to do when CONFIG_PM is off is a separate matter. Let's not > > worry about it for now -- especially since, as Matthias suggested, > > you can use a USB 2.0 hub. > > Not every hub will work (none of available did so far), and it is often > not an option for embedded device without rewiring. It's odd that your hubs don't work. What's wrong with them? > As this touches powerpc stuff only, are there any objections to let > powerpc peolple consider if approach suggested earlier is applicable or > not? I don't mind doing that, provided the changes are cleaned up so that they don't affect people who aren't building kernels for 44x systems. Alan Stern _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev