1ba51a7c14
The acpi_pci_propagate_wakeup() routine is there to handle cases in which PCI bridges (or PCIe ports) are expected to signal wakeup for devices below them, but currently it doesn't do that correctly. The problem is that acpi_pci_propagate_wakeup() uses acpi_pm_set_device_wakeup() for bridges and if that routine is called for multiple times to disable wakeup for the same device, it will disable it on the first invocation and the next calls will have no effect (it works analogously when called to enable wakeup, but that is not a problem). Now, say acpi_pci_propagate_wakeup() has been called for two different devices under the same bridge and it has called acpi_pm_set_device_wakeup() for that bridge each time. The bridge is now enabled to generate wakeup signals. Next, suppose that one of the devices below it resumes and acpi_pci_propagate_wakeup() is called to disable wakeup for that device. It will then call acpi_pm_set_device_wakeup() for the bridge and that will effectively disable remote wakeup for all devices under it even though some of them may still be suspended and remote wakeup may be expected to work for them. To address this (arguably theoretical) issue, allow wakeup.enable_count under struct acpi_device to grow beyond 1 in certain situations. In particular, allow that to happen in acpi_pci_propagate_wakeup() when wakeup is enabled or disabled for PCI bridges, so that wakeup is actually disabled for the bridge when all devices under it resume and not when just one of them does that. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> |
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arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
README
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.