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Subject[ 64/69] usb: PS3 EHCI QH read work-around
3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Geoff Levand <geoff@infradead.org>

commit aaa0ef289afe9186f81e2340114ea413eef0492a upstream.

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@infradead.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/host/ehci-hcd.c | 1 +
1 file changed, 1 insertion(+)

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;



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