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>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/usb/host/ohci-ppc-soc.c b/drivers/usb/host/ohci-ppc-soc.c
index 1a2e1777ca61..f95be1896b0d 100644
--- a/drivers/usb/host/ohci-ppc-soc.c
+++ b/drivers/usb/host/ohci-ppc-soc.c
@@ -73,6 +73,11 @@ static int usb_hcd_ppc_soc_probe(const struct hc_driver *driver,
 
         ohci = hcd_to_ohci(hcd);
         ohci->flags |= OHCI_QUIRK_BE_MMIO | OHCI_QUIRK_BE_DESC;
+
+#ifdef CONFIG_PPC_MPC52xx
+        /* MPC52xx doesn't need frame_no shift */
+        ohci->flags |= OHCI_QUIRK_FRAME_NO;
+#endif
         ohci_hcd_init(ohci);
 
         retval = usb_add_hcd(hcd, irq, IRQF_DISABLED);