Messages in this thread | | | Date | Tue, 8 Apr 2014 23:12:06 -0500 | Subject | USB: OMAP: questions on patch "Implement runtime idling and remote wakeup for OMAP EHCI controller" | From | Chao Xu <> |
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Hi,
I have two questions about this patch series. Any help is appreciated. 1. in the cover letter(https://lkml.org/lkml/2013/7/10/355), it states "the series implements suspend/resume for the OMAP EHCI host controller during runtime idle". I don't understand when is the EHCI host controller "runtime idle"? Does "runtime idle" refers to when all attached USB devices are suspended? or does it refer to whenever there is no tx/rx ongoing in the EHCI host controller?
2. I think the purpose of the patch is to allow the USB power domain (namely, L3INIT power domain) to enter low power state. So assuming the power domain is now in RETENTION state, will the EHCI host be able to detect remote wakeup in this case? i.e. will the ULPI DATA0, DATA1 and DATA3 reflect the Linestate and Interrupt when the L3INIT power domain is in RETENTION? Put it in another way, when the power domain in is a low power state defined in OMAP spec, is the USB host and PHY in "low power mode" defined in USB spec?
Thank you!
Regards, Chao Xu
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