1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 8969e42434b9..c5a2f83991dc 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -582,10 +582,12 @@ void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
         }
 
         /* The USB 2.0 spec says 256 ms.  This is close enough and won't
-         * exceed that limit if HZ is 100. */
+         * exceed that limit if HZ is 100. The math is more clunky than
+         * maybe expected, this is to make sure that all timers for USB devices
+         * fire at the same time to give the CPU a break inbetween */
         if (hcd->uses_new_polling ? hcd->poll_rh :
                         (length == 0 && hcd->status_urb != NULL))
-                mod_timer (&hcd->rh_timer, jiffies + msecs_to_jiffies(250));
+                mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 }
 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
 
@@ -614,8 +616,8 @@ static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
                 urb->hcpriv = hcd;      /* indicate it's queued */
 
                 if (!hcd->uses_new_polling)
-                        mod_timer (&hcd->rh_timer, jiffies +
-                                        msecs_to_jiffies(250));
+                        mod_timer (&hcd->rh_timer,
+                                (jiffies/(HZ/4) + 1) * (HZ/4));
 
                 /* If a status change has already occurred, report it ASAP */
                 else if (hcd->poll_pending)