USB: retain USB device power/wakeup setting across reconfiguration

Currently a non-root-hub USB device's wakeup settings are initialized when the
device is set to a configured state using device_init_wakeup(), but this is not
correct as wakeup is split into "capable" (can_wakeup) and "enabled"
(should_wakeup).  The settings should be initialized instead in the device
initialization (usb_new_device) with the "capable" setting disabled and the
"enabled" setting enabled.  The "capable" setting should be set based on the
device being configured or unconfigured, and "enabled" setting set based on
the sysfs power/wakeup control.

This patch retains the sysfs power/wakeup setting of a non-root-hub USB device
over a USB device re-configuration, which can happen (for example) after a
suspend/resume cycle.

Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 12 insertions, 4 deletions

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index bb416cdee1a7..6f84d383ecee 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1448,11 +1448,11 @@ void usb_set_device_state(struct usb_device *udev,
                                         || new_state == USB_STATE_SUSPENDED)
                                 ;       /* No change to wakeup settings */
                         else if (new_state == USB_STATE_CONFIGURED)
-                                device_init_wakeup(&udev->dev,
+                                device_set_wakeup_capable(&udev->dev,
                                         (udev->actconfig->desc.bmAttributes
                                          & USB_CONFIG_ATT_WAKEUP));
                         else
-                                device_init_wakeup(&udev->dev, 0);
+                                device_set_wakeup_capable(&udev->dev, 0);
                 }
                 if (udev->state == USB_STATE_SUSPENDED &&
                         new_state != USB_STATE_SUSPENDED)
@@ -1799,10 +1799,18 @@ int usb_new_device(struct usb_device *udev)
 {
         int err;
 
-        /* Increment the parent's count of unsuspended children */
-        if (udev->parent)
+        if (udev->parent) {
+                /* Increment the parent's count of unsuspended children */
                 usb_autoresume_device(udev->parent);
 
+                /* Initialize non-root-hub device wakeup to disabled;
+                 * device (un)configuration controls wakeup capable
+                 * sysfs power/wakeup controls wakeup enabled/disabled
+                 */
+                device_init_wakeup(&udev->dev, 0);
+                device_set_wakeup_enable(&udev->dev, 1);
+        }
+
         usb_detect_quirks(udev);
         err = usb_enumerate_device(udev);       /* Read descriptors */
         if (err < 0)