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The hub driver was recently changed to use "global" suspend for system suspend transitions on non-SuperSpeed buses. This means that we don't suspend devices individually by setting the suspend feature on the upstream hub port; instead devices all go into suspend automatically when the root hub stops transmitting packets. The idea was to save time and to avoid certain kinds of wakeup races. Now it turns out that many hubs are buggy; they don't relay wakeup requests from a downstream port to their upstream port if the downstream port's suspend feature is not set (depending on the speed of the downstream port, whether or not the hub is enabled for remote wakeup, and possibly other factors). We can't have hubs dropping wakeup requests. Therefore this patch goes partway back to the old policy: It sets the suspend feature for a port if the device attached to that port or any of its descendants is enabled for wakeup. People will still be able to benefit from the time savings if they don't care about wakeup and leave it disabled on all their devices. In order to accomplish this, the patch adds a new field to the usb_hub structure: wakeup_enabled_descendants is a count of how many devices below a suspended hub are enabled for remote wakeup. A corresponding new subroutine determines the number of wakeup-enabled devices at or below an arbitrary suspended USB device. This should be applied to the 3.10 stable kernel. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-and-tested-by: Toralf Förster <toralf.foerster@gmx.de> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| .. | ||
| buffer.c | ||
| config.c | ||
| devices.c | ||
| devio.c | ||
| driver.c | ||
| endpoint.c | ||
| file.c | ||
| generic.c | ||
| hcd-pci.c | ||
| hcd.c | ||
| hub.c | ||
| hub.h | ||
| Kconfig | ||
| Makefile | ||
| message.c | ||
| notify.c | ||
| otg_whitelist.h | ||
| port.c | ||
| quirks.c | ||
| sysfs.c | ||
| urb.c | ||
| usb-acpi.c | ||
| usb.c | ||
| usb.h | ||