diff options
| author | Edward Shao <laface.tw@gmail.com> | 2010-02-11 03:37:30 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-03-15 08:50:07 -0700 |
| commit | bbb4ae3e0220f07cc88eb7398d7742add03542f1 (patch) | |
| tree | 8abcd0a6b906377b28e19a377752f167e1c4655d | |
| parent | 75bf39e2123146df574e7c1b7ce9ae7c45a44ded (diff) | |
USB: xhci: Fix finding extended capabilities registers
commit 05197921ff3dad52d99fd1647974c57d9c28d40e upstream.
According "5.3.6 Capability Parameters (HCCPARAMS)" of xHCI rev0.96 spec,
value of xECP register indicates a relative offset, in 32-bit words,
from Base to the beginning of the first extended capability.
The wrong calculation will cause BIOS handoff fail (not handoff from BIOS)
in some platform with BIOS USB legacy sup support.
Signed-off-by: Edward Shao <laface.tw@gmail.com>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | drivers/usb/host/xhci-ext-caps.h | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/drivers/usb/host/xhci-ext-caps.h b/drivers/usb/host/xhci-ext-caps.h index ecc131c3fe3..78c4edac1db 100644 --- a/drivers/usb/host/xhci-ext-caps.h +++ b/drivers/usb/host/xhci-ext-caps.h @@ -101,12 +101,15 @@ static inline int xhci_find_next_cap_offset(void __iomem *base, int ext_offset) next = readl(base + ext_offset); - if (ext_offset == XHCI_HCC_PARAMS_OFFSET) + if (ext_offset == XHCI_HCC_PARAMS_OFFSET) { /* Find the first extended capability */ next = XHCI_HCC_EXT_CAPS(next); - else + ext_offset = 0; + } else { /* Find the next extended capability */ next = XHCI_EXT_CAPS_NEXT(next); + } + if (!next) return 0; /* |