[PATCH 4.9 31/44] usb: host: xhci-plat: Fix timeout on removal of hot pluggable xhci controllers

Greg Kroah-Hartman
2017-03-16T14:33:38Z

From: Guenter Roeck <linux@roeck-us.net>

commit dcc7620cad5ad1326a78f4031a7bf4f0e5b42984 upstream.

Upstream commit 98d74f9ceaef ("xhci: fix 10 second timeout on removal of
PCI hotpluggable xhci controllers") fixes a problem with hot pluggable PCI
xhci controllers which can result in excessive timeouts, to the point where
the system reports a deadlock.

The same problem is seen with hot pluggable xhci controllers using the
xhci-plat driver, such as the driver used for Type-C ports on rk3399.
Similar to hot-pluggable PCI controllers, the driver for this chip
removes the xhci controller from the system when the Type-C cable is
disconnected.

The solution for PCI devices works just as well for non-PCI devices
and avoids the problem.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/host/xhci-plat.c | 2 ++
1 file changed, 2 insertions(+)

--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -274,6 +274,8 @@ static int xhci_plat_remove(struct platf
struct xhci_hcd *xhci = hcd_to_xhci(hcd);
struct clk *clk = xhci->clk;

+ xhci->xhc_state |= XHCI_STATE_REMOVING;
+
usb_remove_hcd(xhci->shared_hcd);
usb_phy_shutdown(hcd->usb_phy);