HWA: avoid constant suspend and resume on the root hub

Prevent the USB core from suspending the HWA root hub since bus_suspend
and bus_resume are not yet supported.  Otherwise the PM system will chew
up CPU time constantly attempting to suspend and resume the root hub but
never succeeding.

Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/usb/host/hwa-hc.c b/drivers/usb/host/hwa-hc.c
index 483990c716aa..5b86ffb88f1c 100644
--- a/drivers/usb/host/hwa-hc.c
+++ b/drivers/usb/host/hwa-hc.c
@@ -161,6 +161,13 @@ static int hwahc_op_start(struct usb_hcd *usb_hcd)
         usb_hcd->uses_new_polling = 1;
         set_bit(HCD_FLAG_POLL_RH, &usb_hcd->flags);
         usb_hcd->state = HC_STATE_RUNNING;
+
+        /*
+         * prevent USB core from suspending the root hub since
+         * bus_suspend and bus_resume are not yet supported.
+         */
+        pm_runtime_get_noresume(&usb_hcd->self.root_hub->dev);
+
         result = 0;
 out:
         mutex_unlock(&wusbhc->mutex);