This access causes hang on Freescale P2020DS board (that has OHCI
provided by ULI 1533 chip).

Since preserving OHCI_FMINTERVAL was originally done only for NVIDIA
hardware and only later (in c6187597) was turned unconditional, and
c6187597 commit message again mentions only NVIDIA, I think it should be
safe to disable preserving OHCI_FMINTERVAL if device vendor is ULI.

Signed-off-by: Nikita Yushchenko <nyushche...@dev.rtsoft.ru>
---
 drivers/usb/host/pci-quirks.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 00661d3..5acbd5b 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -571,7 +571,7 @@ static void quirk_usb_handoff_ohci(struct pci_dev *pdev)
 {
        void __iomem *base;
        u32 control;
-       u32 fminterval;
+       u32 uninitialized_var(fminterval);
        int cnt;
 
        if (!mmio_resource_enabled(pdev, 0))
@@ -619,7 +619,8 @@ static void quirk_usb_handoff_ohci(struct pci_dev *pdev)
        }
 
        /* software reset of the controller, preserving HcFmInterval */
-       fminterval = readl(base + OHCI_FMINTERVAL);
+       if (pdev->vendor != PCI_VENDOR_ID_AL)
+               fminterval = readl(base + OHCI_FMINTERVAL);
        writel(OHCI_HCR, base + OHCI_CMDSTATUS);
 
        /* reset requires max 10 us delay */
@@ -628,7 +629,8 @@ static void quirk_usb_handoff_ohci(struct pci_dev *pdev)
                        break;
                udelay(1);
        }
-       writel(fminterval, base + OHCI_FMINTERVAL);
+       if (pdev->vendor != PCI_VENDOR_ID_AL)
+               writel(fminterval, base + OHCI_FMINTERVAL);
 
        /* Now the controller is safely in SUSPEND and nothing can wake it up */
        iounmap(base);
-- 
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to