[PATCH v2] xhci: Fix front USB ports on ASUS PRIME B350M-A

From: Kai-Heng Feng
Date: Mon Feb 19 2018 - 14:06:35 EST


When a USB device gets plugged on ASUS PRIME B350M-A's front ports, the
xHC stops working:
[ 549.114587] xhci_hcd 0000:02:00.0: WARN: xHC CMD_RUN timeout
[ 549.114608] suspend_common(): xhci_pci_suspend+0x0/0xc0 returns -110
[ 549.114638] xhci_hcd 0000:02:00.0: can't suspend (hcd_pci_runtime_suspend returned -110)

Delay before running xHC command CMD_RUN can workaround the issue.

Use a new quirk to make the delay only targets to the affected xHC.

Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
---
v2: Instead of doing xHC reset and disabling D3cold, a simple delay can
workaround the issue. Now both high-speed and super-speed devices work
fine with the v2 quirk.

drivers/usb/host/xhci-pci.c | 3 +++
drivers/usb/host/xhci.c | 3 +++
drivers/usb/host/xhci.h | 1 +
3 files changed, 7 insertions(+)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 6c79037876db..9a820b3cae56 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -122,6 +122,9 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
if (pdev->vendor == PCI_VENDOR_ID_AMD && usb_amd_find_chipset_info())
xhci->quirks |= XHCI_AMD_PLL_FIX;

+ if (pdev->vendor == PCI_VENDOR_ID_AMD && pdev->device == 0x43bb)
+ xhci->quirks |= XHCI_SUSPEND_DELAY;
+
if (pdev->vendor == PCI_VENDOR_ID_AMD)
xhci->quirks |= XHCI_TRUST_TX_LENGTH;

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 1eeb3396300f..d554bbd694d3 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -878,6 +878,9 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
clear_bit(HCD_FLAG_POLL_RH, &xhci->shared_hcd->flags);
del_timer_sync(&xhci->shared_hcd->rh_timer);

+ if (xhci->quirks & XHCI_SUSPEND_DELAY)
+ usleep_range(1000, 1500);
+
spin_lock_irq(&xhci->lock);
clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
clear_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 96099a245c69..6f1f52f3cb40 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1825,6 +1825,7 @@ struct xhci_hcd {
/* Reserved. It was XHCI_U2_DISABLE_WAKE */
#define XHCI_ASMEDIA_MODIFY_FLOWCONTROL (1 << 28)
#define XHCI_HW_LPM_DISABLE (1 << 29)
+#define XHCI_SUSPEND_DELAY (1 << 30)

unsigned int num_active_eps;
unsigned int limit_active_eps;
--
2.15.1