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>
This commit is contained in:
David Brownell
2006-08-04 11:31:55 -07:00
committed by Greg Kroah-Hartman
parent 06afff00bc
commit d413984ae9
13 changed files with 101 additions and 47 deletions

View File

@@ -382,8 +382,10 @@ ohci_omap_start (struct usb_hcd *hcd)
int ret;
config = hcd->self.controller->platform_data;
if (config->otg || config->rwc)
if (config->otg || config->rwc) {
ohci->hc_control = OHCI_CTRL_RWC;
writel(OHCI_CTRL_RWC, &ohci->regs->control);
}
if ((ret = ohci_run (ohci)) < 0) {
dev_err(hcd->self.controller, "can't start\n");
@@ -429,6 +431,7 @@ static const struct hc_driver ohci_omap_hc_driver = {
*/
.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,