USB: add flag for HCDs that can't receive wakeup requests (isp1760-hcd)
Currently the USB stack assumes that all host controller drivers are
capable of receiving wakeup requests from downstream devices.
However, this isn't true for the isp1760-hcd driver, which means that
it isn't safe to do a runtime suspend of any device attached to a
root-hub port if the device requires wakeup.
This patch adds a "cant_recv_wakeups" flag to the usb_hcd structure
and sets the flag in isp1760-hcd. The core is modified to prevent a
direct child of the root hub from being put into runtime suspend with
wakeup enabled if the flag is set.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Nicolas Pitre <nico@linaro.org>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index c76ec97..818369a 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1780,6 +1780,18 @@
dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");
return -EOPNOTSUPP;
}
+
+ /*
+ * If the device is a direct child of the root hub and the HCD
+ * doesn't handle wakeup requests, don't allow autosuspend when
+ * wakeup is needed.
+ */
+ if (w && udev->parent == udev->bus->root_hub &&
+ bus_to_hcd(udev->bus)->cant_recv_wakeups) {
+ dev_dbg(&udev->dev, "HCD doesn't handle wakeup requests\n");
+ return -EOPNOTSUPP;
+ }
+
udev->do_remote_wakeup = w;
return 0;
}
