board/freescale/p2020ds/linux-fix-c6187597-breakage.patch

   1 From: Nikita Yushchenko <nyushchenko@dev.rtsoft.ru>
   2 Subject: [PATCH] usb: pci-quirks: do not access OHCI_FMINTERVAL register on ULI hw
   3
   4 This access causes hang on Freescale P2020DS board (that has OHCI
   5 provided by ULI 1533 chip).
   6
   7 Since preserving OHCI_FMINTERVAL was originally done only for NVIDIA
   8 hardware and only later (in c6187597) was turned unconditional, and
   9 c6187597 commit message again mentions only NVIDIA, I think it should be
  10 safe to disable preserving OHCI_FMINTERVAL if device vendor is ULI.
  11
  12 Signed-off-by: Nikita Yushchenko <nyushchenko@dev.rtsoft.ru>
  13 ---
  14  drivers/usb/host/pci-quirks.c |    8 +++++---
  15  1 file changed, 5 insertions(+), 3 deletions(-)
  16
  17 diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
  18 index 00661d3..5acbd5b 100644
  19 --- a/drivers/usb/host/pci-quirks.c
  20 +++ b/drivers/usb/host/pci-quirks.c
  21 @@ -571,7 +571,7 @@ static void quirk_usb_handoff_ohci(struct pci_dev *pdev)
  22  {
  23         void __iomem *base;
  24         u32 control;
  25 -       u32 fminterval;
  26 +       u32 uninitialized_var(fminterval);
  27         int cnt;
  28
  29         if (!mmio_resource_enabled(pdev, 0))
  30 @@ -619,7 +619,8 @@ static void quirk_usb_handoff_ohci(struct pci_dev *pdev)
  31         }
  32
  33         /* software reset of the controller, preserving HcFmInterval */
  34 -       fminterval = readl(base + OHCI_FMINTERVAL);
  35 +       if (pdev->vendor != PCI_VENDOR_ID_AL)
  36 +               fminterval = readl(base + OHCI_FMINTERVAL);
  37         writel(OHCI_HCR, base + OHCI_CMDSTATUS);
  38
  39         /* reset requires max 10 us delay */
  40 @@ -628,7 +629,8 @@ static void quirk_usb_handoff_ohci(struct pci_dev *pdev)
  41                         break;
  42                 udelay(1);
  43         }
  44 -       writel(fminterval, base + OHCI_FMINTERVAL);
  45 +       if (pdev->vendor != PCI_VENDOR_ID_AL)
  46 +               writel(fminterval, base + OHCI_FMINTERVAL);
  47
  48         /* Now the controller is safely in SUSPEND and nothing can wake it up */
  49         iounmap(base);
  50 --
  51 1.7.10.4