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authorAlan Stern <stern@rowland.harvard.edu>2009-06-29 10:47:30 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2009-07-12 15:16:39 -0700
commit914b701280a76f96890ad63eb0fa99bf204b961c (patch)
tree9373723da74f660aa667da000301c191b1929bd8 /drivers/usb/host/ehci-q.c
parentcb88a1b887bb8908f6e00ce29e893ea52b074940 (diff)
USB: EHCI: use the new clear_tt_buffer interface
This patch (as1256) changes ehci-hcd and all the other drivers in the EHCI family to make use of the new clear_tt_buffer callbacks. When a Clear-TT-Buffer request is in progress for a QH, the QH is not allowed to be linked into the async schedule until the request is finished. At that time, if there are any URBs queued for the QH, it is linked into the async schedule. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/host/ehci-q.c')
-rw-r--r--drivers/usb/host/ehci-q.c91
1 files changed, 68 insertions, 23 deletions
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 68bf81e982d2..e3d2b627bfb3 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -139,6 +139,55 @@ qh_refresh (struct ehci_hcd *ehci, struct ehci_qh *qh)
/*-------------------------------------------------------------------------*/
+static void qh_link_async(struct ehci_hcd *ehci, struct ehci_qh *qh);
+
+static void ehci_clear_tt_buffer_complete(struct usb_hcd *hcd,
+ struct usb_host_endpoint *ep)
+{
+ struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+ struct ehci_qh *qh = ep->hcpriv;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ehci->lock, flags);
+ qh->clearing_tt = 0;
+ if (qh->qh_state == QH_STATE_IDLE && !list_empty(&qh->qtd_list)
+ && HC_IS_RUNNING(hcd->state))
+ qh_link_async(ehci, qh);
+ spin_unlock_irqrestore(&ehci->lock, flags);
+}
+
+static void ehci_clear_tt_buffer(struct ehci_hcd *ehci, struct ehci_qh *qh,
+ struct urb *urb, u32 token)
+{
+
+ /* If an async split transaction gets an error or is unlinked,
+ * the TT buffer may be left in an indeterminate state. We
+ * have to clear the TT buffer.
+ *
+ * Note: this routine is never called for Isochronous transfers.
+ */
+ if (urb->dev->tt && !usb_pipeint(urb->pipe) && !qh->clearing_tt) {
+#ifdef DEBUG
+ struct usb_device *tt = urb->dev->tt->hub;
+ dev_dbg(&tt->dev,
+ "clear tt buffer port %d, a%d ep%d t%08x\n",
+ urb->dev->ttport, urb->dev->devnum,
+ usb_pipeendpoint(urb->pipe), token);
+#endif /* DEBUG */
+ if (!ehci_is_TDI(ehci)
+ || urb->dev->tt->hub !=
+ ehci_to_hcd(ehci)->self.root_hub) {
+ if (usb_hub_clear_tt_buffer(urb) == 0)
+ qh->clearing_tt = 1;
+ } else {
+
+ /* REVISIT ARC-derived cores don't clear the root
+ * hub TT buffer in this way...
+ */
+ }
+ }
+}
+
static int qtd_copy_status (
struct ehci_hcd *ehci,
struct urb *urb,
@@ -195,28 +244,6 @@ static int qtd_copy_status (
usb_pipeendpoint (urb->pipe),
usb_pipein (urb->pipe) ? "in" : "out",
token, status);
-
- /* if async CSPLIT failed, try cleaning out the TT buffer */
- if (status != -EPIPE
- && urb->dev->tt
- && !usb_pipeint(urb->pipe)
- && ((token & QTD_STS_MMF) != 0
- || QTD_CERR(token) == 0)
- && (!ehci_is_TDI(ehci)
- || urb->dev->tt->hub !=
- ehci_to_hcd(ehci)->self.root_hub)) {
-#ifdef DEBUG
- struct usb_device *tt = urb->dev->tt->hub;
- dev_dbg (&tt->dev,
- "clear tt buffer port %d, a%d ep%d t%08x\n",
- urb->dev->ttport, urb->dev->devnum,
- usb_pipeendpoint (urb->pipe), token);
-#endif /* DEBUG */
- /* REVISIT ARC-derived cores don't clear the root
- * hub TT buffer in this way...
- */
- usb_hub_clear_tt_buffer(urb);
- }
}
return status;
@@ -407,9 +434,16 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh)
/* qh unlinked; token in overlay may be most current */
if (state == QH_STATE_IDLE
&& cpu_to_hc32(ehci, qtd->qtd_dma)
- == qh->hw_current)
+ == qh->hw_current) {
token = hc32_to_cpu(ehci, qh->hw_token);
+ /* An unlink may leave an incomplete
+ * async transaction in the TT buffer.
+ * We have to clear it.
+ */
+ ehci_clear_tt_buffer(ehci, qh, urb, token);
+ }
+
/* force halt for unlinked or blocked qh, so we'll
* patch the qh later and so that completions can't
* activate it while we "know" it's stopped.
@@ -435,6 +469,13 @@ halt:
&& (qtd->hw_alt_next
& EHCI_LIST_END(ehci)))
last_status = -EINPROGRESS;
+
+ /* As part of low/full-speed endpoint-halt processing
+ * we must clear the TT buffer (11.17.5).
+ */
+ if (unlikely(last_status != -EINPROGRESS &&
+ last_status != -EREMOTEIO))
+ ehci_clear_tt_buffer(ehci, qh, urb, token);
}
/* if we're removing something not at the queue head,
@@ -864,6 +905,10 @@ static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
__hc32 dma = QH_NEXT(ehci, qh->qh_dma);
struct ehci_qh *head;
+ /* Don't link a QH if there's a Clear-TT-Buffer pending */
+ if (unlikely(qh->clearing_tt))
+ return;
+
/* (re)start the async schedule? */
head = ehci->async;
timer_action_done (ehci, TIMER_ASYNC_OFF);