6.12-stable review patch. If anyone has any objections, please let me know.
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From: Huacai Chen chenhuacai@loongson.cn
commit bcb60d438547355b8f9ad48645909139b64d3482 upstream.
The OHCI controller (rev 0x02) under LS7A PCI host has a hardware flaw. MMIO register with offset 0x60/0x64 is treated as legacy PS2-compatible keyboard/mouse interface, which confuse the OHCI controller. Since OHCI only use a 4KB BAR resource indeed, the LS7A OHCI controller's 32KB BAR is wrapped around (the second 4KB BAR space is the same as the first 4KB internally). So we can add an 4KB offset (0x1000) to the OHCI registers (from the PCI BAR resource) as a quirk.
Cc: stable stable@kernel.org Suggested-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Alan Stern stern@rowland.harvard.edu Tested-by: Mingcong Bai baimingcong@loongson.cn Signed-off-by: Huacai Chen chenhuacai@loongson.cn Link: https://lore.kernel.org/r/20250328040059.3672979-1-chenhuacai@loongson.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/host/ohci-pci.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)
--- a/drivers/usb/host/ohci-pci.c +++ b/drivers/usb/host/ohci-pci.c @@ -165,6 +165,25 @@ static int ohci_quirk_amd700(struct usb_ return 0; }
+static int ohci_quirk_loongson(struct usb_hcd *hcd) +{ + struct pci_dev *pdev = to_pci_dev(hcd->self.controller); + + /* + * Loongson's LS7A OHCI controller (rev 0x02) has a + * flaw. MMIO register with offset 0x60/64 is treated + * as legacy PS2-compatible keyboard/mouse interface. + * Since OHCI only use 4KB BAR resource, LS7A OHCI's + * 32KB BAR is wrapped around (the 2nd 4KB BAR space + * is the same as the 1st 4KB internally). So add 4KB + * offset (0x1000) to the OHCI registers as a quirk. + */ + if (pdev->revision == 0x2) + hcd->regs += SZ_4K; /* SZ_4K = 0x1000 */ + + return 0; +} + static int ohci_quirk_qemu(struct usb_hcd *hcd) { struct ohci_hcd *ohci = hcd_to_ohci(hcd); @@ -225,6 +244,10 @@ static const struct pci_device_id ohci_p .driver_data = (unsigned long)ohci_quirk_amd700, }, { + PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a24), + .driver_data = (unsigned long)ohci_quirk_loongson, + }, + { .vendor = PCI_VENDOR_ID_APPLE, .device = 0x003f, .subvendor = PCI_SUBVENDOR_ID_REDHAT_QUMRANET,