From fac4271d1126c45ceaceb7f4a336317b771eb121 Mon Sep 17 00:00:00 2001 From: Zhuang Jin Can Date: Tue, 21 Jul 2015 17:20:30 +0300 Subject: [PATCH] xhci: prevent bus_suspend if SS port resuming in phase 1 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] Cc: Signed-off-by: Zhuang Jin Can Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman --- 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 7df8878cc37b..fdca8edc5836 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -1123,10 +1123,10 @@ 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 94416ff70810..6a8fc52aed58 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1546,6 +1546,9 @@ 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 31e46cc55807..ed2ebf647c38 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)