PCI/PM: Keep parent bridge active when probing device
This patch fixes the following bug:
http://marc.info/?l=linux-pci&m=134329923124234&w=2
The root cause of the bug is as follow.
If a device is not bound with the corresponding driver, the device
runtime PM will be disabled and the device will be put into suspended
state. So that, the bridge/PCIe port connected to it may be put into
suspended and low power state. When do probing for the device later,
because the bridge/PCIe port connected to it is in low power state,
the IO access to device may fail.
To solve the issue, the bridge/PCIe port connected to the device is
put into active state before probing.
Reported-by: Bjorn Mork <bjorn@mork.no>
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>
1 file changed