[PATCH 4.19 199/267] PCI: Avoid Pericom USB controller OHCI/EHCI PME# defect

Greg Kroah-Hartman
2020-06-19T15:02:20Z

From: Kai-Heng Feng <kai.heng.feng@canonical.com>

[ Upstream commit 68f5fc4ea9ddf9f77720d568144219c4e6452cde ]

Both Pericom OHCI and EHCI devices advertise PME# support from all power
states:

06:00.0 USB controller [0c03]: Pericom Semiconductor PI7C9X442SL USB OHCI Controller [12d8:400e] (rev 01) (prog-if 10 [OHCI])
Subsystem: Pericom Semiconductor PI7C9X442SL USB OHCI Controller [12d8:400e]
Capabilities: [80] Power Management version 3
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+)

06:00.2 USB controller [0c03]: Pericom Semiconductor PI7C9X442SL USB EHCI Controller [12d8:400f] (rev 01) (prog-if 20 [EHCI])
Subsystem: Pericom Semiconductor PI7C9X442SL USB EHCI Controller [12d8:400f]
Capabilities: [80] Power Management version 3
Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+)

But testing shows that it's unreliable: there is a 20% chance PME# won't be
asserted when a USB device is plugged.

Remove PME support for both devices to make USB plugging work reliably.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=205981
Link: https://lore.kernel.org/r/20200508065343.32751-2-kai.heng.feng@canonical.com
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/quirks.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index ca41cff2e68c..fb061e1bc084 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -5294,6 +5294,19 @@ static void pci_fixup_no_d0_pme(struct pci_dev *dev)
}
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ASMEDIA, 0x2142, pci_fixup_no_d0_pme);

+/*
+ * Device [12d8:0x400e] and [12d8:0x400f]
+ * These devices advertise PME# support in all power states but don't
+ * reliably assert it.
+ */
+static void pci_fixup_no_pme(struct pci_dev *dev)
+{
+ pci_info(dev, "PME# is unreliable, disabling it\n");
+ dev->pme_support = 0;
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400e, pci_fixup_no_pme);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400f, pci_fixup_no_pme);
+
static void apex_pci_fixup_class(struct pci_dev *pdev)
{
pdev->class = (PCI_CLASS_SYSTEM_OTHER << 8) | pdev->class;
--
2.25.1