PCI: PM: Replace pci_dev_keep_suspended() with two functions

The code in pci_dev_keep_suspended() is relatively hard to follow due
to the negative checks in it and in its callers and the function has
a possible side-effect (disabling the PME) which doesn't really match
its role.

For this reason, move the PME disabling from pci_dev_keep_suspended()
to a separate function and change the semantics (and name) of the
rest of it, so that 'true' is returned when the device needs to be
resumed (and not the other way around).  Change the callers of
pci_dev_keep_suspended() accordingly.

While at it, make the code flow in pci_pm_poweroff() reflect the
pci_pm_suspend() more closely to avoid arbitrary differences between
them.

This is a cosmetic change with no intention to alter behavior.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

1 files changed, 28 insertions, 27 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 324175509e94..24d86bd1bba1 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2459,55 +2459,56 @@ bool pci_dev_run_wake(struct pci_dev *dev)
 EXPORT_SYMBOL_GPL(pci_dev_run_wake);
 
 /**
- * pci_dev_keep_suspended - Check if the device can stay in the suspended state.
+ * pci_dev_need_resume - Check if it is necessary to resume the device.
  * @pci_dev: Device to check.
  *
- * Return 'true' if the device is runtime-suspended, it doesn't have to be
+ * Return 'true' if the device is not runtime-suspended or it has to be
  * reconfigured due to wakeup settings difference between system and runtime
- * suspend and the current power state of it is suitable for the upcoming
- * (system) transition.
- *
- * If the device is not configured for system wakeup, disable PME for it before
- * returning 'true' to prevent it from waking up the system unnecessarily.
+ * suspend, or the current power state of it is not suitable for the upcoming
+ * (system-wide) transition.
  */
-bool pci_dev_keep_suspended(struct pci_dev *pci_dev)
+bool pci_dev_need_resume(struct pci_dev *pci_dev)
 {
 	struct device *dev = &pci_dev->dev;
-	bool wakeup = device_may_wakeup(dev);
 	pci_power_t target_state;
 
 	if (!pm_runtime_suspended(dev) || platform_pci_need_resume(pci_dev))
-		return false;
+		return true;
 
-	target_state = pci_target_state(pci_dev, wakeup);
+	target_state = pci_target_state(pci_dev, device_may_wakeup(dev));
 
 	/*
 	 * If the earlier platform check has not triggered, D3cold is just power
 	 * removal on top of D3hot, so no need to resume the device in that
 	 * case.
 	 */
-	if (target_state != pci_dev->current_state &&
-	    target_state != PCI_D3cold && pci_dev->current_state != PCI_D3hot)
-		return false;
+	return target_state != pci_dev->current_state &&
+		target_state != PCI_D3cold &&
+		pci_dev->current_state != PCI_D3hot;
+}
+
+/**
+ * pci_dev_adjust_pme - Adjust PME setting for a suspended device.
+ * @pci_dev: Device to check.
+ *
+ * If the device is suspended and it is not configured for system wakeup,
+ * disable PME for it to prevent it from waking up the system unnecessarily.
+ *
+ * Note that if the device's power state is D3cold and the platform check in
+ * pci_dev_need_resume() has not triggered, the device's configuration need not
+ * be changed.
+ */
+void pci_dev_adjust_pme(struct pci_dev *pci_dev)
+{
+	struct device *dev = &pci_dev->dev;
 
-	/*
-	 * At this point the device is good to go unless it's been configured
-	 * to generate PME at the runtime suspend time, but it is not supposed
-	 * to wake up the system.  In that case, simply disable PME for it
-	 * (it will have to be re-enabled on exit from system resume).
-	 *
-	 * If the device's power state is D3cold and the platform check above
-	 * hasn't triggered, the device's configuration is suitable and we don't
-	 * need to manipulate it at all.
-	 */
 	spin_lock_irq(&dev->power.lock);
 
-	if (pm_runtime_suspended(dev) && pci_dev->current_state < PCI_D3cold &&
-	    !wakeup)
+	if (pm_runtime_suspended(dev) && !device_may_wakeup(dev) &&
+	    pci_dev->current_state < PCI_D3cold)
 		__pci_pme_active(pci_dev, false);
 
 	spin_unlock_irq(&dev->power.lock);
-	return true;
 }
 
 /**