PCI: reset pci device state to unknown state for resume
authorShaohua Li <shaohua.li@intel.com>
Fri, 20 Oct 2006 21:45:32 +0000 (14:45 -0700)
committerGreg Kroah-Hartman <gregkh@suse.de>
Fri, 27 Oct 2006 18:20:33 +0000 (11:20 -0700)
commit2449e06a5696b7af1c8a369b04c97f3b139cf3bb
tree22ee432f869df8c703fb25035e06d4e92d56be7f
parent3095fc0c9772b4afb3c81f76664f341ef716d380
PCI: reset pci device state to unknown state for resume

Considering below scenario:
1.Unload a PCI device's driver, the device ->current remains in PCI_D0.
2.Do suspend/resume circle. After that, BIOS puts the device to D3.
3.Reload the device driver. The calling pci_set_power_state in the
driver can't change the state to D0, as set_power_state thinks the
device is already in D0.

A bug is reported at http://bugzilla.kernel.org/show_bug.cgi?id=6024
Pat attached a patch at
http://marc.theaimsgroup.com/?l=linux-pci&m=114049761428561&w=2 for this
issue, but it's lost. As pci_set_power_state can handle D3 -> D0
correctly (restore config space), I simplified Patrick's patch.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Cc: Patrick Mochel <mochel@digitalimplant.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/pci/pci-driver.c