From: Zhuang Jin Can <jin.can.zhuang@xxxxxxxxx>
This patch has been added to the 3.12 stable tree. If you have any
objections, please let us know.
===============
commit fac4271d1126c45ceaceb7f4a336317b771eb121 upstream.
When the link is just waken, it's in Resume state, and driver sets PLS to
U0. This refers to Phase 1. Phase 2 refers to when the link has completed
the transition from Resume state to U0.
With the fix of xhci: report U3 when link is in resume state, it also
exposes an issue that usb3 roothub and controller can suspend right
after phase 1, and this causes a hard hang in controller.
To fix the issue, we need to prevent usb3 bus suspend if any port is
resuming in phase 1.
[merge separate USB2 and USB3 port resume checking to one -Mathias]
Signed-off-by: Zhuang Jin Can <jin.can.zhuang@xxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/usb/host/xhci-hub.c | 6 +++---
drivers/usb/host/xhci-ring.c | 3 +++
drivers/usb/host/xhci.h | 1 +
3 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 86cebec3c5d6..4adc1be24b4a 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -1120,10 +1120,10 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
spin_lock_irqsave(&xhci->lock, flags);
if (hcd->self.root_hub->do_remote_wakeup) {
- if (bus_state->resuming_ports) {
+ if (bus_state->resuming_ports || /* USB2 */
+ bus_state->port_remote_wakeup) { /* USB3 */
spin_unlock_irqrestore(&xhci->lock, flags);
- xhci_dbg(xhci, "suspend failed because "
- "a port is resuming\n");
+ xhci_dbg(xhci, "suspend failed because a port is resuming\n");
return -EBUSY;
}
}
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 07aafa50f453..b16404723fc2 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1707,6 +1707,9 @@ static void handle_port_status(struct xhci_hcd *xhci,
usb_hcd_resume_root_hub(hcd);
}
+ if (hcd->speed == HCD_USB3 && (temp & PORT_PLS_MASK) == XDEV_INACTIVE)
+ bus_state->port_remote_wakeup &= ~(1 << faked_port_index);
+
if ((temp & PORT_PLC) && (temp & PORT_PLS_MASK) == XDEV_RESUME) {
xhci_dbg(xhci, "port resume event for port %d\n", port_id);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 510e9c0efd18..8686a06d83d4 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -285,6 +285,7 @@ struct xhci_op_regs {
#define XDEV_U0 (0x0 << 5)
#define XDEV_U2 (0x2 << 5)
#define XDEV_U3 (0x3 << 5)
+#define XDEV_INACTIVE (0x6 << 5)
#define XDEV_RESUME (0xf << 5)
/* true: port has power (see HCC_PPC) */
#define PORT_POWER (1 << 9)
--
2.5.0
--
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