usb: hub: Prevent hub autosuspend if usbcore.autosuspend is -1

commit bdd405d2a5287bdb9b04670ea255e1f122138e66 upstream.

If user specifies that USB autosuspend must be disabled by module
parameter "usbcore.autosuspend=-1" then we must prevent
autosuspend of USB hub devices as well.

commit 596d789a211d introduced in v3.8 changed the original behaivour
and stopped respecting the usbcore.autosuspend parameter for hubs.

Fixes: 596d789a211d "USB: set hub's default autosuspend delay as 0"
Signed-off-by: Roger Quadros <rogerq@ti.com>
Tested-by: Michael Welling <mwelling@emacinc.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 7e90d146d7dd8eaa7db65adf5c7ae886f4d72398..813697d72466fd7ca55bccf8be276607b7dc922a 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1699,8 +1699,12 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
         * - Change autosuspend delay of hub can avoid unnecessary auto
         *   suspend timer for hub, also may decrease power consumption
         *   of USB bus.
+        *
+        * - If user has indicated to prevent autosuspend by passing
+        *   usbcore.autosuspend = -1 then keep autosuspend disabled.
         */
-       pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
+       if (hdev->dev.power.autosuspend_delay >= 0)
+               pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
 
        /*
         * Hubs have proper suspend/resume support, except for root hubs