[PATCH 1/1] PCI: Disable MSI for Pericom PCIe-USB adapter

Kai-Heng Feng kai.heng.feng at canonical.com
Fri Dec 4 14:21:55 UTC 2020


From: Andy Shevchenko <andriy.shevchenko at linux.intel.com>

BugLink: https://bugs.launchpad.net/bugs/1906839

Pericom PCIe-USB adapter advertises MSI, but documentation says "The MSI
Function is not implemented on this device" in chapters 7.3.27,
7.3.29-7.3.31, and Alberto found that MSI in fact does not work.

Disable MSI for these devices.

Datasheet: https://www.diodes.com/assets/Datasheets/PI7C9X440SL.pdf
Fixes: 306c54d0edb6 ("usb: hcd: Try MSI interrupts on PCI devices")
Link: https://lore.kernel.org/linux-usb/20201030134826.GP4077@smile.fi.intel.com/
Link: https://lore.kernel.org/r/20201106100526.17726-1-andriy.shevchenko@linux.intel.com
Reported-by: alberto.vignani at fastwebnet.it
Signed-off-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas at google.com>
(cherry picked from commit f83c37941e881224885f2e694e0626bea358e96b linux-next)
Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
---
 drivers/pci/quirks.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 2396055bdef2..818128b75e29 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -5604,17 +5604,26 @@ 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]
+ * Device 12d8:0x400e [OHCI] and 12d8:0x400f [EHCI]
+ *
  * These devices advertise PME# support in all power states but don't
  * reliably assert it.
+ *
+ * These devices also advertise MSI, but documentation (PI7C9X440SL.pdf)
+ * says "The MSI Function is not implemented on this device" in chapters
+ * 7.3.27, 7.3.29-7.3.31.
  */
-static void pci_fixup_no_pme(struct pci_dev *dev)
+static void pci_fixup_no_msi_no_pme(struct pci_dev *dev)
 {
+#ifdef CONFIG_PCI_MSI
+	pci_info(dev, "MSI is not implemented on this device, disabling it\n");
+	dev->no_msi = 1;
+#endif
 	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);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400e, pci_fixup_no_msi_no_pme);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_PERICOM, 0x400f, pci_fixup_no_msi_no_pme);
 
 static void apex_pci_fixup_class(struct pci_dev *pdev)
 {
-- 
2.29.2




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