USB: add runtime frame_no quirk for big-endian OHCI
Add OHCI big endian frame_no quirk. The frame_no value stored in the
HCCA is a 16 bit field at a specific offset, but since not all CPUs can
do 16-bit memory accesses it's used as a 32 bit field. And that's why
big-endian OHCI must shift 16 bits ... unless the spec is not followed.
Currently there's one MPC52xx platform that doesn't need the shift. This
patch adds a new "big endian frame_no" quirk to control that at runtime.
Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
Acked-by: Dale Farnsworth <dale@farnsworth.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/ohci-ppc-of.c b/drivers/usb/host/ohci-ppc-of.c
index c43b66a..0a74269 100644
--- a/drivers/usb/host/ohci-ppc-of.c
+++ b/drivers/usb/host/ohci-ppc-of.c
@@ -134,8 +134,11 @@
}
ohci = hcd_to_ohci(hcd);
- if (is_bigendian)
+ if (is_bigendian) {
ohci->flags |= OHCI_QUIRK_BE_MMIO | OHCI_QUIRK_BE_DESC;
+ if (of_device_is_compatible(dn, "mpc5200-ohci"))
+ ohci->flags |= OHCI_QUIRK_FRAME_NO;
+ }
ohci_hcd_init(ohci);