[Resend][PATCH 1/2] PCI: Clear saved_state after the state has been restored

From: Rafael J. Wysocki
Date: Wed Sep 09 2009 - 17:49:11 EST


From: Rafael J. Wysocki <rjw@xxxxxxx>

Some PCI devices fail if their standard configuration registers are
restored twice in a row. Prevent this from happening by making
pci_restore_state() clear the saved_state flag of the device right
after the device's standard configuration registers have been
populated with the previously saved values.

Simplify PCI PM callbacks by removing the direct clearing of
state_saved from them, as it shouldn't be necessary any more (except
in pci_pm_thaw(), where it has to be cleared, so that the values saved
during the "freeze" phase of hibernation are not used later by mistake).

Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
---
drivers/pci/pci-driver.c | 11 ++---------
drivers/pci/pci.c | 3 +++
drivers/pci/probe.c | 3 +++
3 files changed, 8 insertions(+), 9 deletions(-)

Index: linux-2.6/drivers/pci/pci-driver.c
===================================================================
--- linux-2.6.orig/drivers/pci/pci-driver.c
+++ linux-2.6/drivers/pci/pci-driver.c
@@ -417,8 +417,6 @@ static int pci_legacy_suspend(struct dev
struct pci_dev * pci_dev = to_pci_dev(dev);
struct pci_driver * drv = pci_dev->driver;

- pci_dev->state_saved = false;
-
if (drv && drv->suspend) {
pci_power_t prev = pci_dev->current_state;
int error;
@@ -514,7 +512,6 @@ static int pci_restore_standard_config(s
static void pci_pm_default_resume_noirq(struct pci_dev *pci_dev)
{
pci_restore_standard_config(pci_dev);
- pci_dev->state_saved = false;
pci_fixup_device(pci_fixup_resume_early, pci_dev);
}

@@ -580,8 +577,6 @@ static int pci_pm_suspend(struct device
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend(dev, PMSG_SUSPEND);

- pci_dev->state_saved = false;
-
if (!pm) {
pci_pm_default_suspend(pci_dev);
goto Fixup;
@@ -716,8 +711,6 @@ static int pci_pm_freeze(struct device *
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend(dev, PMSG_FREEZE);

- pci_dev->state_saved = false;
-
if (!pm) {
pci_pm_default_suspend(pci_dev);
return 0;
@@ -793,6 +786,8 @@ static int pci_pm_thaw(struct device *de
pci_pm_reenable_device(pci_dev);
}

+ pci_dev->state_saved = false;
+
return error;
}

@@ -804,8 +799,6 @@ static int pci_pm_poweroff(struct device
if (pci_has_legacy_pm_support(pci_dev))
return pci_legacy_suspend(dev, PMSG_HIBERNATE);

- pci_dev->state_saved = false;
-
if (!pm) {
pci_pm_default_suspend(pci_dev);
goto Fixup;
Index: linux-2.6/drivers/pci/pci.c
===================================================================
--- linux-2.6.orig/drivers/pci/pci.c
+++ linux-2.6/drivers/pci/pci.c
@@ -852,6 +852,7 @@ pci_restore_state(struct pci_dev *dev)

if (!dev->state_saved)
return 0;
+
/* PCI Express register must be restored first */
pci_restore_pcie_state(dev);

@@ -873,6 +874,8 @@ pci_restore_state(struct pci_dev *dev)
pci_restore_msi_state(dev);
pci_restore_iov_state(dev);

+ dev->state_saved = false;
+
return 0;
}

Index: linux-2.6/drivers/pci/probe.c
===================================================================
--- linux-2.6.orig/drivers/pci/probe.c
+++ linux-2.6/drivers/pci/probe.c
@@ -1009,6 +1009,9 @@ void pci_device_add(struct pci_dev *dev,
/* Fix up broken headers */
pci_fixup_device(pci_fixup_header, dev);

+ /* Clear the state_saved flag. */
+ dev->state_saved = false;
+
/* Initialize various capabilities */
pci_init_capabilities(dev);

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