PCI: Avoid broken MSI on SB600 USB devices

Some ATI SB600 USB adapters advertise MSI, but if INTx is disabled by
setting PCI_COMMAND_INTX_DISABLE, MSI doesn't work either.  The PCI/PCIe
specs do not require software to set PCI_COMMAND_INTX_DISABLE when enabling
MSI, but Linux has done that for many years.

Mick reported that 306c54d ("usb: hcd: Try MSI interrupts on PCI
devices") broke these devices.  Prior to 306c54d, they used INTx.
Starting with 306c54d, they use MSI, and and the fact that Linux sets
PCI_COMMAND_INTX_DISABLE means both INTx and MSI are disabled on these
devices.

Avoid this SB600 defect by disabling MSI so we use INTx as before.

Fixes: 306c54d ("usb: hcd: Try MSI interrupts on PCI devices")
Link: https://lore.kernel.org/r/[email protected]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215690
Link: https://lore.kernel.org/all/PxIByDyBRcsbpcmVhGSNDFAoUcMmb78ctXCkw6fbpx25TGlCHvA6SJjjFkNr1FfQZMntYPTNyvEnblxzAZ8a6jP9ddLpKeCN6Chi_2FuexU=@protonmail.com/
Link: https://lore.kernel.org/r/[email protected]
BugLink: https://lore.kernel.org/all/[email protected]/
Reported-by: Mick Lorain <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>

drivers/pci/quirks.c

@@ -1811,6 +1811,18 @@ static void quirk_alder_ioapic(struct pci_dev *pdev)
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL,	PCI_DEVICE_ID_INTEL_EESSC,	quirk_alder_ioapic);
 #endif
 
+static void quirk_no_msi(struct pci_dev *dev)
+{
+	pci_info(dev, "avoiding MSI to work around a hardware defect\n");
+	dev->no_msi = 1;
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x4386, quirk_no_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x4387, quirk_no_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x4388, quirk_no_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x4389, quirk_no_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x438a, quirk_no_msi);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x438b, quirk_no_msi);
+
 static void quirk_pcie_mch(struct pci_dev *pdev)
 {
 	pdev->no_msi = 1;