OHCI: add a quirk for ULi M5237 blocking on reset

commit 56abcab833fafcfaeb2f5b25e0364c1dec45f53e upstream.

Commit 8dccddbc2368 ("OHCI: final fix for NVIDIA problems (I hope)")
introduced into 3.1.9 broke boot on e.g. Freescale P2020DS development
board. The code path that was previously specific to NVIDIA controllers
had then become taken for all chips.

However, the M5237 installed on the board wedges solid when accessing
its base+OHCI_FMINTERVAL register, making it impossible to boot any
kernel newer than 3.1.8 on this particular and apparently other similar
machines.

Don't readl() and writel() base+OHCI_FMINTERVAL on PCI ID 10b9:5237.

The patch is suitable for the -next tree as well as all maintained
kernels up to 3.2 inclusive.

Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zefan Li <lizefan@huawei.com>

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index 90dcf54cd7e8864c3f1c2273aa6f8b7d089cab69..1f230edfedf9824f5f0f852fe7af3a2814669c56 100644 (file)
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -470,7 +470,8 @@ static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
 {
        void __iomem *base;
        u32 control;
-       u32 fminterval;
+       u32 fminterval = 0;
+       bool no_fminterval = false;
        int cnt;
 
        if (!mmio_resource_enabled(pdev, 0))
@@ -480,6 +481,13 @@ static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
        if (base == NULL)
                return;
 
+       /*
+        * ULi M5237 OHCI controller locks the whole system when accessing
+        * the OHCI_FMINTERVAL offset.
+        */
+       if (pdev->vendor == PCI_VENDOR_ID_AL && pdev->device == 0x5237)
+               no_fminterval = true;
+
        control = readl(base + OHCI_CONTROL);
 
 /* On PA-RISC, PDC can leave IR set incorrectly; ignore it there. */
@@ -518,7 +526,9 @@ static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
        }
 
        /* software reset of the controller, preserving HcFmInterval */
-       fminterval = readl(base + OHCI_FMINTERVAL);
+       if (!no_fminterval)
+               fminterval = readl(base + OHCI_FMINTERVAL);
+
        writel(OHCI_HCR, base + OHCI_CMDSTATUS);
 
        /* reset requires max 10 us delay */
@@ -527,7 +537,9 @@ static void __devinit quirk_usb_handoff_ohci(struct pci_dev *pdev)
                        break;
                udelay(1);
        }
-       writel(fminterval, base + OHCI_FMINTERVAL);
+
+       if (!no_fminterval)
+               writel(fminterval, base + OHCI_FMINTERVAL);
 
        /* Now the controller is safely in SUSPEND and nothing can wake it up */
        iounmap(base);