[34-longterm 156/179] USB: xhci: fix OS want to own HC

From: Paul Gortmaker
Date: Mon May 14 2012 - 22:30:41 EST

From: JiSheng Zhang <jszhang3@xxxxxxxxx>

This is a commit scheduled for the next v2.6.34 longterm release.
If you see a problem with using this for longterm, please comment.

commit 6768458b17f9bf48a4c3a34e49b20344091b5f7e upstream.

Software should set XHCI_HC_OS_OWNED bit to request ownership of xHC.

This patch should be backported to kernels as far back as 2.6.31.

Signed-off-by: JiSheng Zhang <jszhang3@xxxxxxxxx>
Signed-off-by: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
drivers/usb/host/pci-quirks.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index bcf7a88..eae8b18 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -444,7 +444,7 @@ static void __devinit quirk_usb_handoff_xhci(struct pci_dev *pdev)

/* If the BIOS owns the HC, signal that the OS wants it, and wait */
if (val & XHCI_HC_BIOS_OWNED) {
- writel(val & XHCI_HC_OS_OWNED, base + ext_cap_offset);
+ writel(val | XHCI_HC_OS_OWNED, base + ext_cap_offset);

/* Wait for 5 seconds with 10 microsecond polling interval */
timeout = handshake(base + ext_cap_offset, XHCI_HC_BIOS_OWNED,

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