From f62795f1e892ca9269849fa83de97621da7e02c0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" <rjw@sisk.pl> Date: Mon, 18 May 2009 22:51:12 +0200 Subject: [PATCH] PCI PM: Follow PCI_PM_CTRL_NO_SOFT_RESET during transitions from D3 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. Cc: stable@kernel.org Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> --- drivers/pci/pci.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1a91bf9687af9..761557688b18d 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -480,6 +480,8 @@ static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state) 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)) -- GitLab