From 2b454d9a5f0507c1bc3f01c06a2e6c464d2a2641 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Fri, 30 Apr 2010 12:09:23 -0400 Subject: [PATCH] USB: fix remote wakeup settings during system sleep This is a backport of commit 5f677f1d45b2bf08085bbba7394392dfa586fa8e. Some of the functionality had to be removed, but it should still fix the webcam problem. This patch (as1363b) 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. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/driver.c | 32 ++++++++++++++++++++++++++++++-- 1 file changed, 30 insertions(+), 2 deletions(-) diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index ca479a7c69b2..d9d0bf5ebd1d 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -1255,9 +1255,8 @@ static int usb_suspend_both(struct usb_device *udev, pm_message_t msg) udev->state == USB_STATE_SUSPENDED) goto done; - udev->do_remote_wakeup = device_may_wakeup(&udev->dev); - if (msg.event & PM_EVENT_AUTO) { + udev->do_remote_wakeup = device_may_wakeup(&udev->dev); status = autosuspend_check(udev, 0); if (status < 0) goto done; @@ -1789,6 +1788,34 @@ int usb_external_resume_device(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) { + 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; + } + } + + udev->do_remote_wakeup = w; +} + int usb_suspend(struct device *dev, pm_message_t msg) { struct usb_device *udev; @@ -1808,6 +1835,7 @@ int usb_suspend(struct device *dev, pm_message_t msg) } udev->skip_sys_resume = 0; + choose_wakeup(udev, msg); return usb_external_suspend_device(udev, msg); } -- 2.39.5