On Wed, 18 Apr 2012, Stephen Warren wrote: > I looked at our downstream ehci-tegra.c, and there's a lot more code > there for suspend/resume, wakeup, and a bunch of other stuff. Given > that, I'm not too surprised that the upstream driver isn't resuming from > suspend as expected. > > I think we can still apply your patch if you want, It's important. Recent changes in usbcore will cause ehci_hub_status_data() to be called after the root hub is suspended. (See commit 879d38e6bc36d73b0ac40ec9b0d839fda9fa8b1a in Greg's USB tree.) If the controller is already powered down, you'll run into trouble. Besides, ehci-tegra might as well use the runtime PM framework for managing the controller's power state. That's what it's for. > but we additionally > need to make CONFIG_USB_EHCI_TEGRA depend on !CONFIG_USB_SUSPEND, which > will ensure nobody gets surprised by this fails-to-resume issue. Does > that seem reasonable? I don't think this will have any user-impact, > since (a) the controllers weren't suspending before this patch, and (b) > neither CONFIG_USB_SUSPEND nor CONFIG_PM_RUNTIME were enabled in > tegra_defconfig (although in 3.5 we'll enable CONFIG_PM_RUNTIME). Are you sure the controllers aren't getting suspending under the current driver? It seems like they ought to be -- otherwise there would be no point in defining power_down_on_bus_suspend. > Those responsible for ehci-tegra.c in our downstream kernels are > supposed to be working on a plan to upstream the missing parts. When > that comes to fruition, we should be able to remove that Kconfig > restriction. I'm afraid I don't have an ETA for when that will be though. Is this patch compatible with the downstream driver? It would be a shame to mess up a bunch of other work. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
