From: Edward Shao <laface.tw@xxxxxxxxx>
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@xxxxxxxxx>
Cc: Sarah Sharp <sarah.a.sharp@xxxxxxxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
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 ecc131c..78c4eda 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;
/*
--
1.7.0.1
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
