[PATCH 3.10 50/55] usb: hub: Prevent hub autosuspend if usbcore.autosuspend is -1

Greg Kroah-Hartman
2014-09-03T23:39:06Z

From: Roger Quadros <rogerq@ti.com>

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>

---
drivers/usb/core/hub.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1699,8 +1699,12 @@ static int hub_probe(struct usb_interfac
* - 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