[PATCH] usb: xhci-mtk: fixup mouse wakeup failure during system suspend
From: Felipe Balbi <hidden>
Date: 2016-05-03 09:35:44
Also in:
linux-mediatek, lkml
Hi, chunfeng yun [off-list ref] writes:
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chunfeng yun [off-list ref] writes:quoted
On Thu, 2016-04-21 at 10:04 +0800, Chunfeng Yun wrote:quoted
Click mouse after xhci suspend completion but before system suspend completion, system will not be waken up by mouse if the duration of them is larger than 20ms which is the device UFP's resume signalingwhat is "them" here ? The duration of what is longer than 20ms ?They are "xhci suspend completion" and "system suspend completion"; It's time duration
okay. So if xhci suspend takes longer than 20ms your SPM doesn't see a wakeup ?
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lasted. Another reason is that the SPM is not enabled before systemwhat's SPM ?It is System Power Management which is powered off when system is running in normal mode, and is powered on when system enters suspend mode. It is used to wakeup system when some wakeup sources, such as bluetooth or powerkey etc, tigger wakeup event.
okay, thanks
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suspend compeltion, this causes SPM also not notice the resume signal.^^^^^^^^^^ completionquoted
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So in order to reduce the duration less than 20ms, make use of syscore's suspend/resume interface.no, this is the wrong approachBut it seems only one workable approach from software side
I wouldn't say that. It seems to me SPM should be enabled earlier.
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Because the syscore runs on irq disabled context, and xhci's suspend/resume calls some sleeping functions, enable local irq and then disable it during suspend/resume. This may be not a problem, since only boot CPU is runing.another problem :) calling local_irq_{enable,disable}() is an indication that something's wrong.Oh! BTW: There will be warning logs if they are not called.
yeah, I got that :-) But it's still wrong to use
local_irq_{enable,disable}() the way you're using them :-)
--
balbi
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