From 253f588c70f66184b1f3a9bbb428b49bbda73e80 Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Thu, 11 Mar 2021 13:53:51 +0200 Subject: xhci: Improve detection of device initiated wake signal. A xHC USB 3 port might miss the first wake signal from a USB 3 device if the port LFPS reveiver isn't enabled fast enough after xHC resume. xHC host will anyway be resumed by a PME# signal, but will go back to suspend if no port activity is seen. The device resends the U3 LFPS wake signal after a 100ms delay, but by then host is already suspended, starting all over from the beginning of this issue. USB 3 specs say U3 wake LFPS signal is sent for max 10ms, then device needs to delay 100ms before resending the wake. Don't suspend immediately if port activity isn't detected in resume. Instead add a retry. If there is no port activity then delay for 120ms, and re-check for port activity. Cc: Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20210311115353.2137560-3-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'drivers/usb/host/xhci.c') diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index bd27bd670104..48a68fcf2b36 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -1088,6 +1088,7 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated) struct usb_hcd *secondary_hcd; int retval = 0; bool comp_timer_running = false; + bool pending_portevent = false; if (!hcd->state) return 0; @@ -1226,13 +1227,22 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated) done: if (retval == 0) { - /* Resume root hubs only when have pending events. */ - if (xhci_pending_portevent(xhci)) { + /* + * Resume roothubs only if there are pending events. + * USB 3 devices resend U3 LFPS wake after a 100ms delay if + * the first wake signalling failed, give it that chance. + */ + pending_portevent = xhci_pending_portevent(xhci); + if (!pending_portevent) { + msleep(120); + pending_portevent = xhci_pending_portevent(xhci); + } + + if (pending_portevent) { usb_hcd_resume_root_hub(xhci->shared_hcd); usb_hcd_resume_root_hub(hcd); } } - /* * If system is subject to the Quirk, Compliance Mode Timer needs to * be re-initialized Always after a system resume. Ports are subject -- cgit v1.2.3 From d26c00e7276fc92b18c253d69e872f6b03832bad Mon Sep 17 00:00:00 2001 From: Mathias Nyman Date: Thu, 11 Mar 2021 13:53:53 +0200 Subject: xhci: Fix repeated xhci wake after suspend due to uncleared internal wake state If port terminations are detected in suspend, but link never reaches U0 then xHCI may have an internal uncleared wake state that will cause an immediate wake after suspend. This wake state is normally cleared when driver clears the PORT_CSC bit, which is set after a device is enabled and in U0. Write 1 to clear PORT_CSC for ports that don't have anything connected when suspending. This makes sure any pending internal wake states in xHCI are cleared. Cc: stable@vger.kernel.org Tested-by: Mika Westerberg Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20210311115353.2137560-5-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 62 ++++++++++++++++++++++++------------------------- 1 file changed, 30 insertions(+), 32 deletions(-) (limited to 'drivers/usb/host/xhci.c') diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 48a68fcf2b36..1975016f46bf 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -883,44 +883,42 @@ static void xhci_clear_command_ring(struct xhci_hcd *xhci) xhci_set_cmd_ring_deq(xhci); } -static void xhci_disable_port_wake_on_bits(struct xhci_hcd *xhci) +/* + * Disable port wake bits if do_wakeup is not set. + * + * Also clear a possible internal port wake state left hanging for ports that + * detected termination but never successfully enumerated (trained to 0U). + * Internal wake causes immediate xHCI wake after suspend. PORT_CSC write done + * at enumeration clears this wake, force one here as well for unconnected ports + */ + +static void xhci_disable_hub_port_wake(struct xhci_hcd *xhci, + struct xhci_hub *rhub, + bool do_wakeup) { - struct xhci_port **ports; - int port_index; unsigned long flags; u32 t1, t2, portsc; + int i; spin_lock_irqsave(&xhci->lock, flags); - /* disable usb3 ports Wake bits */ - port_index = xhci->usb3_rhub.num_ports; - ports = xhci->usb3_rhub.ports; - while (port_index--) { - t1 = readl(ports[port_index]->addr); - portsc = t1; - t1 = xhci_port_state_to_neutral(t1); - t2 = t1 & ~PORT_WAKE_BITS; - if (t1 != t2) { - writel(t2, ports[port_index]->addr); - xhci_dbg(xhci, "disable wake bits port %d-%d, portsc: 0x%x, write: 0x%x\n", - xhci->usb3_rhub.hcd->self.busnum, - port_index + 1, portsc, t2); - } - } + for (i = 0; i < rhub->num_ports; i++) { + portsc = readl(rhub->ports[i]->addr); + t1 = xhci_port_state_to_neutral(portsc); + t2 = t1; + + /* clear wake bits if do_wake is not set */ + if (!do_wakeup) + t2 &= ~PORT_WAKE_BITS; + + /* Don't touch csc bit if connected or connect change is set */ + if (!(portsc & (PORT_CSC | PORT_CONNECT))) + t2 |= PORT_CSC; - /* disable usb2 ports Wake bits */ - port_index = xhci->usb2_rhub.num_ports; - ports = xhci->usb2_rhub.ports; - while (port_index--) { - t1 = readl(ports[port_index]->addr); - portsc = t1; - t1 = xhci_port_state_to_neutral(t1); - t2 = t1 & ~PORT_WAKE_BITS; if (t1 != t2) { - writel(t2, ports[port_index]->addr); - xhci_dbg(xhci, "disable wake bits port %d-%d, portsc: 0x%x, write: 0x%x\n", - xhci->usb2_rhub.hcd->self.busnum, - port_index + 1, portsc, t2); + writel(t2, rhub->ports[i]->addr); + xhci_dbg(xhci, "config port %d-%d wake bits, portsc: 0x%x, write: 0x%x\n", + rhub->hcd->self.busnum, i + 1, portsc, t2); } } spin_unlock_irqrestore(&xhci->lock, flags); @@ -983,8 +981,8 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup) return -EINVAL; /* Clear root port wake on bits if wakeup not allowed. */ - if (!do_wakeup) - xhci_disable_port_wake_on_bits(xhci); + xhci_disable_hub_port_wake(xhci, &xhci->usb3_rhub, do_wakeup); + xhci_disable_hub_port_wake(xhci, &xhci->usb2_rhub, do_wakeup); if (!HCD_HW_ACCESSIBLE(hcd)) return 0; -- cgit v1.2.3