Bug 196091

Summary: Runtime PM enabled AMD EHCI controller cannot be woken up when devices get plugged in.
Product: Drivers Reporter: Kai-Heng Feng (kai.heng.feng)
Component: PCIAssignee: drivers_pci (drivers_pci)
Status: RESOLVED CODE_FIX    
Severity: normal    
Priority: P1    
Hardware: x86-64   
OS: Linux   
Kernel Version: 4.12-rc5 Subsystem:
Regression: No Bisected commit-id:
Attachments: lspci -vv

Description Kai-Heng Feng 2017-06-16 09:10:00 UTC 
Created attachment 257017 [details]
lspci -vv

The laptop is an AMD Carrizo laptop.
The two right USB ports are connected to EHCI controller, which does not respond to any device plugging event.

There's no PME signal at device plugging, so it's a hardware bug [1].
After some testing, we found that the PME signal can work under D2 but not D3 [2].

So we can write a quirk to workaround this issue.

[1] https://www.spinics.net/lists/linux-usb/msg157462.html
[2] http://www.spinics.net/lists/linux-pci/msg62137.html
Comment 1 Kai-Heng Feng 2019-04-04 08:55:17 UTC 
Fixed by commit 0bf3730bbc41f155543fa63becb4ff436d6a00a9 ("x86/PCI: Avoid AMD SB7xx EHCI USB wakeup defect")