diff options
| author | Geoff Levand <geoff@infradead.org> | 2011-11-08 16:01:18 -0800 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2012-06-19 23:18:27 +0100 |
| commit | 5f081af6cbb83e72194ad3a82623ca42eeb0e662 (patch) | |
| tree | 9f15f8452856bf80f45eab0df08b0d00e1687308 | |
| parent | 29623c3e8dd0a0b94f2f3ee6ccb08345acff2b1e (diff) | |
| download | lwn-5f081af6cbb83e72194ad3a82623ca42eeb0e662.tar.gz lwn-5f081af6cbb83e72194ad3a82623ca42eeb0e662.zip | |
usb: PS3 EHCI QH read work-around
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>
| -rw-r--r-- | 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 da2f7118a81c..64c0d7b5a903 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -620,6 +620,7 @@ 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; |