Commit 7560d32e authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

USB: improve runtime remote wakeup settings 



This patch (as1362) adjusts the way the USB autosuspend routines
handle remote-wakeup settings.  They aren't supposed to use
device_may_wakeup(); that test is intended only for system sleep, not
runtime power management.  Instead the code checks to see if any
interface drivers need remote wakeup; if they do then it is enabled,
provided the device is capable of it.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent ff9c895f

drivers/usb/core/driver.c

+8 −11
Original line number Diff line number Diff line
@@ -1486,9 +1486,6 @@ int usb_autoresume_device(struct usb_device *udev) 
 * 0, a delayed autosuspend request for @intf's device is attempted.  The

 * attempt may fail (see autosuspend_check()).

 *

 * If the driver has set @intf->needs_remote_wakeup then autosuspend will

 * take place only if the device's remote-wakeup facility is enabled.

 *

 * This routine can run only in process context.

 */

void usb_autopm_put_interface(struct usb_interface *intf)
@@ -1673,14 +1670,14 @@ EXPORT_SYMBOL_GPL(usb_autopm_get_interface_no_resume); 
/* Internal routine to check whether we may autosuspend a device. */

static int autosuspend_check(struct usb_device *udev)

{

	int			i;

	int			w, i;

	struct usb_interface	*intf;

	unsigned long		suspend_time, j;



	/* Fail if autosuspend is disabled, or any interfaces are in use, or

	 * any interface drivers require remote wakeup but it isn't available.

	 */

	udev->do_remote_wakeup = device_may_wakeup(&udev->dev);

	w = 0;

	if (udev->actconfig) {

		for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {

			intf = udev->actconfig->interface[i];
@@ -1694,12 +1691,7 @@ static int autosuspend_check(struct usb_device *udev) 
				continue;

			if (atomic_read(&intf->dev.power.usage_count) > 0)

				return -EBUSY;

			if (intf->needs_remote_wakeup &&

					!udev->do_remote_wakeup) {

				dev_dbg(&udev->dev, "remote wakeup needed "

						"for autosuspend\n");

				return -EOPNOTSUPP;

			}

			w |= intf->needs_remote_wakeup;



			/* Don't allow autosuspend if the device will need

			 * a reset-resume and any of its interface drivers
@@ -1715,6 +1707,11 @@ static int autosuspend_check(struct usb_device *udev) 
			}

		}

	}

	if (w && !device_can_wakeup(&udev->dev)) {

		dev_dbg(&udev->dev, "remote wakeup needed for autosuspend\n");

		return -EOPNOTSUPP;

	}

	udev->do_remote_wakeup = w;



	/* If everything is okay but the device hasn't been idle for long

	 * enough, queue a delayed autosuspend request.

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