From: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> This patch (as1363) changes the way USB remote wakeup is handled during system sleeps. It won't be enabled unless an interface driver specifically needs it. Also, it won't be enabled during the FREEZE or QUIESCE phases of hibernation, when the system doesn't respond to wakeup events anyway. Finally, if the device is already runtime-suspended with remote wakeup enabled, but wakeup is supposed to be disabled for the system sleep, the device gets woken up so that it can be suspended again with the proper wakeup setting. This will fix problems people have reported with certain USB webcams that generate wakeup requests when they shouldn't, and as a result cause system suspends to fail. See https://bugs.launchpad.net/ubuntu/+source/linux/+bug/515109 Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Tested-by: Erik Andrén <erik.andren@xxxxxxxxx> CC: <stable@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx> --- drivers/usb/core/driver.c | 36 +++++++++++++++++++++++++++++++++++- 1 files changed, 35 insertions(+), 1 deletions(-) diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index 6a3b5ca..64b91d6 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1263,13 +1263,47 @@ static int usb_resume_both(struct usb_device *udev, pm_message_t msg) return status; } +static void choose_wakeup(struct usb_device *udev, pm_message_t msg) +{ + int w, i; + struct usb_interface *intf; + + /* Remote wakeup is needed only when we actually go to sleep. + * For things like FREEZE and QUIESCE, if the device is already + * autosuspended then its current wakeup setting is okay. + */ + if (msg.event == PM_EVENT_FREEZE || msg.event == PM_EVENT_QUIESCE) { + if (udev->state != USB_STATE_SUSPENDED) + udev->do_remote_wakeup = 0; + return; + } + + /* If remote wakeup is permitted, see whether any interface drivers + * actually want it. + */ + w = 0; + if (device_may_wakeup(&udev->dev) && udev->actconfig) { + for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { + intf = udev->actconfig->interface[i]; + w |= intf->needs_remote_wakeup; + } + } + + /* If the device is autosuspended with the wrong wakeup setting, + * autoresume now so the setting can be changed. + */ + if (udev->state == USB_STATE_SUSPENDED && w != udev->do_remote_wakeup) + pm_runtime_resume(&udev->dev); + udev->do_remote_wakeup = w; +} + /* The device lock is held by the PM core */ int usb_suspend(struct device *dev, pm_message_t msg) { struct usb_device *udev = to_usb_device(dev); do_unbind_rebind(udev, DO_UNBIND); - udev->do_remote_wakeup = device_may_wakeup(&udev->dev); + choose_wakeup(udev, msg); return usb_suspend_both(udev, msg); } -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
