USB: OHCI avoids root hub timer polling
This teaches OHCI to use the root hub status change (RHSC) IRQ, bypassing
root hub timers most of the time and switching over to the "new" root hub
polling scheme. It's complicated by the fact that implementations of OHCI
trigger and ack that IRQ differently (the spec is vague there).
Avoiding root hub timers helps mechanisms like "dynamic tick" leave the
CPU in lowpower modes for longer intervals.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/ohci-pxa27x.c b/drivers/usb/host/ohci-pxa27x.c
index 6f559e1..2752d36 100644
--- a/drivers/usb/host/ohci-pxa27x.c
+++ b/drivers/usb/host/ohci-pxa27x.c
@@ -288,6 +288,7 @@
*/
.hub_status_data = ohci_hub_status_data,
.hub_control = ohci_hub_control,
+ .hub_irq_enable = ohci_rhsc_enable,
#ifdef CONFIG_PM
.bus_suspend = ohci_bus_suspend,
.bus_resume = ohci_bus_resume,