On an AMD Carrizo laptop, when EHCI runtime PM is enabled, EHCI ports do not respond to any device plugging event. As Alan Stern points out [1], the PME signal is not enabled when controller is in D3, therefore it's not being woken up when new deivces get plugged in. Testing shows PME signal works when the EHCI power state is D2. Bjorn Helgaas suggests to flip bits PCI_PM_CAP_PME_D3 and PCI_PM_CAP_PME_D3cold in PCI fixup. Link: https://bugzilla.kernel.org/show_bug.cgi?id=196091 Link: https://support.amd.com/TechDocs/46837.pdf (Section 23) Link: https://support.amd.com/TechDocs/42413.pdf (Appendix A2) Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> --- arch/x86/pci/fixup.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c index 6d52b94f4bb9..0f71a908e262 100644 --- a/arch/x86/pci/fixup.c +++ b/arch/x86/pci/fixup.c @@ -571,3 +571,18 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2fc0, pci_invalid_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6f60, pci_invalid_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fa0, pci_invalid_bar); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fc0, pci_invalid_bar); + +/* + * Device [1022:7808] + * 23. USB Wake on Connect/Disconnect with Low Speed Devices + * https://support.amd.com/TechDocs/46837.pdf + * Appendix A2 + * https://support.amd.com/TechDocs/42413.pdf + */ +static void pci_fixup_amd_ehci_pme(struct pci_dev *dev) +{ + dev_info(&dev->dev, "PME# does not work under D3, disabling it\n"); + dev->pme_support &= ~(PCI_PM_CAP_PME_D3 | PCI_PM_CAP_PME_D3cold) + >> PCI_PM_CAP_PME_SHIFT; +} +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, 0x7808, pci_fixup_amd_ehci_pme); -- 2.13.1
