[Cbe-oss-dev] [PATCH 4/4] usb: PS3 EHCI QH read work-around

[Geoff Levand]

PS3 EHCI HC errata fix 244.  The SCC EHCI HC will not correctly perform QH
reads that occur near or span a micro-frame boundry.  This is due to a problem
in the Nak Count Reload Control logic (EHCI Specification 1.0 Section 4.9.1).

The work-around for this problem is for the HC driver to set I=1 (inactive) for
QHs with H=1 (list head).

Signed-off-by: Geoff Levand <geoff at infradead.org>
Acked-by: Alan Stern <stern at rowland.harvard.edu>
---
 drivers/usb/host/ehci-hcd.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index e0ca995..9496b7d 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -670,6 +670,7 @@ static int ehci_init(struct usb_hcd *hcd)
 	hw = ehci->async->hw;
 	hw->hw_next = QH_NEXT(ehci, ehci->async->qh_dma);
 	hw->hw_info1 = cpu_to_hc32(ehci, QH_HEAD);
+	hw->hw_info1 |= cpu_to_hc32(ehci, (1 << 7));	/* I = 1 */
 	hw->hw_token = cpu_to_hc32(ehci, QTD_STS_HALT);
 	hw->hw_qtd_next = EHCI_LIST_END(ehci);
 	ehci->async->qh_state = QH_STATE_LINKED;
-- 
1.7.0.4