On Mon, 18 May 2009 22:51:12 +0200 "Rafael J. Wysocki" <rjw@xxxxxxx> wrote: > From: Rafael J. Wysocki <rjw@xxxxxxx> > > According to the PCI PM specification (PCI Bus Power Management > Interface Specification, Rev. 1.2, Section 5.4.1) we are supposed to > reinitialize devices that have PCI_PM_CTRL_NO_SOFT_RESET clear during > all transitions from PCI_D3hot to PCI_D0, but we only do it if the > device's current_state field is equal to PCI_UNKNOWN. > > This may lead to problems if a device with PCI_PM_CTRL_NO_SOFT_RESET > unset is put into PCI_D3hot at run time by its driver and > pci_set_power_state() is used to put it back into PCI_D0, because in > that case the device will remain uninitialized after > pci_set_power_state() has returned. Prevent that from happening by > modifying pci_raw_set_power_state() to reinitialize devices with > PCI_PM_CTRL_NO_SOFT_RESET unset during all transitions from D3 to D0. > > Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> > --- > drivers/pci/pci.c | 2 ++ > 1 file changed, 2 insertions(+) > > Index: linux-2.6/drivers/pci/pci.c > =================================================================== > --- linux-2.6.orig/drivers/pci/pci.c > +++ linux-2.6/drivers/pci/pci.c > @@ -480,6 +480,8 @@ static int pci_raw_set_power_state(struc > pmcsr &= ~PCI_PM_CTRL_STATE_MASK; > pmcsr |= state; > break; > + case PCI_D3hot: > + case PCI_D3cold: > case PCI_UNKNOWN: /* Boot-up */ > if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot > && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET)) > Applied to my linux-next branch, thanks Rafael. I've also included stable@xxxxxxxxxx in the cc, since this is a small but important fix. -- Jesse Barnes, Intel Open Source Technology Center _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
