PCI/PM: Enable D3/D3cold by default for most devices

This patch fixes the following bug:

http://marc.info/?l=linux-usb&m=134318961120825&w=2

Originally, device lower power states include D1, D2, D3.  After that,
D3 is further divided into D3hot and D3cold.  To support both scenario
safely, original D3 is mapped to D3cold.

When adding D3cold support, because worry about some device may have
broken D3cold support, D3cold is disabled by default.  This disable D3
on original platform too.  But some original platform may only have
working D3, but no working D1, D2.  The root cause of the above bug is
it too.

To deal with this, this patch enables D3/D3cold by default for most
devices.  This restores the original behavior.  For some devices that
suspected to have broken D3cold support, such as PCIe port, D3cold is
disabled by default.

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>

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index f3ea977a5b1bf6f458c8ed0757cd8e02cc1d3ff2..ab4bf5a4c2f12ee6dc90a83666d03387fc618fca 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1941,6 +1941,7 @@ void pci_pm_init(struct pci_dev *dev)
        dev->pm_cap = pm;
        dev->d3_delay = PCI_PM_D3_WAIT;
        dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
+       dev->d3cold_allowed = true;
 
        dev->d1_support = false;
        dev->d2_support = false;

diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c
index 3a7eefcb270a5dda9a2dcbcead63086da4433c3e..62f5a76c8f8084083958d737973fb62820197404 100644 (file)
--- a/drivers/pci/pcie/portdrv_pci.c
+++ b/drivers/pci/pcie/portdrv_pci.c
@@ -200,6 +200,11 @@ static int __devinit pcie_portdrv_probe(struct pci_dev *dev,
                return status;
 
        pci_save_state(dev);
+       /*
+        * D3cold may not work properly on some PCIe port, so disable
+        * it by default.
+        */
+       dev->d3cold_allowed = false;
        if (!pci_match_id(port_runtime_pm_black_list, dev))
                pm_runtime_put_noidle(&dev->dev);