From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
This patch (as1245) fixes a bug in ehci-hcd. When an URB is queued
for an endpoint whose QH is already in the LINKED state, the QH
doesn't get refreshed. As a result, if usb_clear_halt() was called
during the time that the QH was linked but idle, the data toggle value
in the QH doesn't get reset.
The symptom is that after a clear_halt, data gets lost and transfers
time out. This problem is starting to show up now because the
"ehci-hcd unlink speedups" patch causes QHs with no queued URBs to
remain linked for a suitable time.
The patch utilizes the new endpoint_reset mechanism to fix the
problem. When an endpoint is reset, the new method forcibly unlinks
the QH (if necessary) and safely updates the toggle value. This
allows qh_update() to be simplified and avoids using usb_device's
toggle bits in a rather unintuitive way.
Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
CC: David Brownell <david-b@xxxxxxxxxxx>
Tested-by: David <david@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/usb/host/ehci-au1xxx.c | 1 +
drivers/usb/host/ehci-fsl.c | 1 +
drivers/usb/host/ehci-hcd.c | 45 ++++++++++++++++++++++++++++++++++++++++
drivers/usb/host/ehci-ixp4xx.c | 1 +
drivers/usb/host/ehci-orion.c | 1 +
drivers/usb/host/ehci-pci.c | 1 +
drivers/usb/host/ehci-ppc-of.c | 1 +
drivers/usb/host/ehci-ps3.c | 1 +
drivers/usb/host/ehci-q.c | 19 +----------------
9 files changed, 53 insertions(+), 18 deletions(-)
diff --git a/drivers/usb/host/ehci-au1xxx.c b/drivers/usb/host/ehci-au1xxx.c
index bf69f47..c3a778b 100644
--- a/drivers/usb/host/ehci-au1xxx.c
+++ b/drivers/usb/host/ehci-au1xxx.c
@@ -97,6 +97,7 @@ static const struct hc_driver ehci_au1xxx_hc_driver = {
.urb_enqueue = ehci_urb_enqueue,
.urb_dequeue = ehci_urb_dequeue,
.endpoint_disable = ehci_endpoint_disable,
+ .endpoint_reset = ehci_endpoint_reset,
/*
* scheduling support
diff --git a/drivers/usb/host/ehci-fsl.c b/drivers/usb/host/ehci-fsl.c
index 01c3da3..bf86809 100644
--- a/drivers/usb/host/ehci-fsl.c
+++ b/drivers/usb/host/ehci-fsl.c
@@ -309,6 +309,7 @@ static const struct hc_driver ehci_fsl_hc_driver = {
.urb_enqueue = ehci_urb_enqueue,
.urb_dequeue = ehci_urb_dequeue,
.endpoint_disable = ehci_endpoint_disable,
+ .endpoint_reset = ehci_endpoint_reset,
/*
* scheduling support
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index a2ca9cb..2b72473 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -1024,6 +1024,51 @@ done:
return;
}
+static void
+ehci_endpoint_reset(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
+{
+ struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+ struct ehci_qh *qh;
+ int eptype = usb_endpoint_type(&ep->desc);
+
+ if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT)
+ return;
+
+ rescan:
+ spin_lock_irq(&ehci->lock);
+ qh = ep->hcpriv;
+
+ /* For Bulk and Interrupt endpoints we maintain the toggle state
+ * in the hardware; the toggle bits in udev aren't used at all.
+ * When an endpoint is reset by usb_clear_halt() we must reset
+ * the toggle bit in the QH.
+ */
+ if (qh) {
+ if (!list_empty(&qh->qtd_list)) {
+ WARN_ONCE(1, "clear_halt for a busy endpoint\n");
+ } else if (qh->qh_state == QH_STATE_IDLE) {
+ qh->hw_token &= ~cpu_to_hc32(ehci, QTD_TOGGLE);
+ } else {
+ /* It's not safe to write into the overlay area
+ * while the QH is active. Unlink it first and
+ * wait for the unlink to complete.
+ */
+ if (qh->qh_state == QH_STATE_LINKED) {
+ if (eptype == USB_ENDPOINT_XFER_BULK) {
+ unlink_async(ehci, qh);
+ } else {
+ intr_deschedule(ehci, qh);
+ (void) qh_schedule(ehci, qh);
+ }
+ }
+ spin_unlock_irq(&ehci->lock);
+ schedule_timeout_uninterruptible(1);
+ goto rescan;
+ }
+ }
+ spin_unlock_irq(&ehci->lock);
+}
+
static int ehci_get_frame (struct usb_hcd *hcd)
{
struct ehci_hcd *ehci = hcd_to_ehci (hcd);
diff --git a/drivers/usb/host/ehci-ixp4xx.c b/drivers/usb/host/ehci-ixp4xx.c
index 9c32063..a44bb4a 100644
--- a/drivers/usb/host/ehci-ixp4xx.c
+++ b/drivers/usb/host/ehci-ixp4xx.c
@@ -51,6 +51,7 @@ static const struct hc_driver ixp4xx_ehci_hc_driver = {
.urb_enqueue = ehci_urb_enqueue,
.urb_dequeue = ehci_urb_dequeue,
.endpoint_disable = ehci_endpoint_disable,
+ .endpoint_reset = ehci_endpoint_reset,
.get_frame_number = ehci_get_frame,
.hub_status_data = ehci_hub_status_data,
.hub_control = ehci_hub_control,
diff --git a/drivers/usb/host/ehci-orion.c b/drivers/usb/host/ehci-orion.c
index 17dc154..770dd9a 100644
--- a/drivers/usb/host/ehci-orion.c
+++ b/drivers/usb/host/ehci-orion.c
@@ -149,6 +149,7 @@ static const struct hc_driver ehci_orion_hc_driver = {
.urb_enqueue = ehci_urb_enqueue,
.urb_dequeue = ehci_urb_dequeue,
.endpoint_disable = ehci_endpoint_disable,
+ .endpoint_reset = ehci_endpoint_reset,
/*
* scheduling support
diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index e749488..f3683e1 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -388,6 +388,7 @@ static const struct hc_driver ehci_pci_hc_driver = {
.urb_enqueue = ehci_urb_enqueue,
.urb_dequeue = ehci_urb_dequeue,
.endpoint_disable = ehci_endpoint_disable,
+ .endpoint_reset = ehci_endpoint_reset,
/*
* scheduling support
diff --git a/drivers/usb/host/ehci-ppc-of.c b/drivers/usb/host/ehci-ppc-of.c
index ef732b7..fbd2722 100644
--- a/drivers/usb/host/ehci-ppc-of.c
+++ b/drivers/usb/host/ehci-ppc-of.c
@@ -61,6 +61,7 @@ static const struct hc_driver ehci_ppc_of_hc_driver = {
.urb_enqueue = ehci_urb_enqueue,
.urb_dequeue = ehci_urb_dequeue,
.endpoint_disable = ehci_endpoint_disable,
+ .endpoint_reset = ehci_endpoint_reset,
/*
* scheduling support
diff --git a/drivers/usb/host/ehci-ps3.c b/drivers/usb/host/ehci-ps3.c
index 1ba9f9a..4b4df23 100644
--- a/drivers/usb/host/ehci-ps3.c
+++ b/drivers/usb/host/ehci-ps3.c
@@ -65,6 +65,7 @@ static const struct hc_driver ps3_ehci_hc_driver = {
.urb_enqueue = ehci_urb_enqueue,
.urb_dequeue = ehci_urb_dequeue,
.endpoint_disable = ehci_endpoint_disable,
+ .endpoint_reset = ehci_endpoint_reset,
.get_frame_number = ehci_get_frame,
.hub_status_data = ehci_hub_status_data,
.hub_control = ehci_hub_control,
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 1976b1b..3192f68 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -93,22 +93,6 @@ qh_update (struct ehci_hcd *ehci, struct ehci_qh *qh, struct ehci_qtd *qtd)
qh->hw_qtd_next = QTD_NEXT(ehci, qtd->qtd_dma);
qh->hw_alt_next = EHCI_LIST_END(ehci);
- /* Except for control endpoints, we make hardware maintain data
- * toggle (like OHCI) ... here (re)initialize the toggle in the QH,
- * and set the pseudo-toggle in udev. Only usb_clear_halt() will
- * ever clear it.
- */
- if (!(qh->hw_info1 & cpu_to_hc32(ehci, 1 << 14))) {
- unsigned is_out, epnum;
-
- is_out = !(qtd->hw_token & cpu_to_hc32(ehci, 1 << 8));
- epnum = (hc32_to_cpup(ehci, &qh->hw_info1) >> 8) & 0x0f;
- if (unlikely (!usb_gettoggle (qh->dev, epnum, is_out))) {
- qh->hw_token &= ~cpu_to_hc32(ehci, QTD_TOGGLE);
- usb_settoggle (qh->dev, epnum, is_out, 1);
- }
- }
-
/* HC must see latest qtd and qh data before we clear ACTIVE+HALT */
wmb ();
qh->hw_token &= cpu_to_hc32(ehci, QTD_TOGGLE | QTD_STS_PING);
@@ -850,7 +834,6 @@ done:
qh->qh_state = QH_STATE_IDLE;
qh->hw_info1 = cpu_to_hc32(ehci, info1);
qh->hw_info2 = cpu_to_hc32(ehci, info2);
- usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe), !is_input, 1);
qh_refresh (ehci, qh);
return qh;
}
@@ -881,7 +864,7 @@ static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
}
}
- /* clear halt and/or toggle; and maybe recover from silicon quirk */
+ /* clear halt and maybe recover from silicon quirk */
if (qh->qh_state == QH_STATE_IDLE)
qh_refresh (ehci, qh);
--
1.6.3.2
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