[REPOST PATCH 3/3] USB: dwc2: Don't turn off the usbphy in suspend if wakeup is enabled

Julius Werner jwerner at chromium.org
Tue Jul 7 17:06:29 PDT 2015

> Doug, how would you feel about reworking the patch that exports
> usb_wakeup_enabled_descendants()?  Instead of doing it that way, create
> and export a new subroutine in hcd.c called
> usb_hcd_wakeup_not_needed(), or something similar.

We have a use case with another host controller (Tegra, which I think
is still in the process of being upstreamed) where we are able to
power down PHYs (and thus reduce power consumption) per port. I think
we should prefer the more flexible 'number of wake devices in subtree'
interface to be able to support cases like that. (And for the simple
case, 'if (usb_hcd_wakeup_not_needed(hcd))' and 'if
(!usb_wakeup_enabled_descendants(hcd->self.root_hub))' look pretty
similar anyway.)

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