From cc56867d3226c1b5f142c77af8de149c0d5f774c Mon Sep 17 00:00:00 2001 From: "Guilherme G. Piccoli" Date: Mon, 20 Nov 2023 13:04:36 -0300 Subject: [PATCH] PCI: Only override AMD USB controller if required [ Upstream commit e585a37e5061f6d5060517aed1ca4ccb2e56a34c ] By running a Van Gogh device (Steam Deck), the following message was noticed in the kernel log: pci 0000:04:00.3: PCI class overridden (0x0c03fe -> 0x0c03fe) so dwc3 driver can claim this instead of xhci Effectively this means the quirk executed but changed nothing, since the class of this device was already the proper one (likely adjusted by newer firmware versions). Check and perform the override only if necessary. Link: https://lore.kernel.org/r/20231120160531.361552-1-gpiccoli@igalia.com Signed-off-by: Guilherme G. Piccoli Signed-off-by: Bjorn Helgaas Cc: Huang Rui Cc: Vicki Pfau Signed-off-by: Sasha Levin --- drivers/pci/quirks.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 8f3b91e0d2644..b5b96d2a9f4ba 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -702,10 +702,13 @@ static void quirk_amd_dwc_class(struct pci_dev *pdev) { u32 class = pdev->class; - /* Use "USB Device (not host controller)" class */ - pdev->class = PCI_CLASS_SERIAL_USB_DEVICE; - pci_info(pdev, "PCI class overridden (%#08x -> %#08x) so dwc3 driver can claim this instead of xhci\n", - class, pdev->class); + if (class != PCI_CLASS_SERIAL_USB_DEVICE) { + /* Use "USB Device (not host controller)" class */ + pdev->class = PCI_CLASS_SERIAL_USB_DEVICE; + pci_info(pdev, + "PCI class overridden (%#08x -> %#08x) so dwc3 driver can claim this instead of xhci\n", + class, pdev->class); + } } DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_NL_USB, quirk_amd_dwc_class);