mei: mei-me: resume device in prepare

Asynchronous runtime resume is not possible while the system
is suspending.
The power management subsystem resumes the device only in the
suspend phase, not in the prepare phase.
Force resume device in prepare to allow drivers on mei bus
to communicate in their prepare callbacks.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>

drivers/misc/mei/pci-me.c

@@ -340,6 +340,12 @@ static void mei_me_remove(struct pci_dev *pdev)
 }
 
 #ifdef CONFIG_PM_SLEEP
+static int mei_me_pci_prepare(struct device *device)
+{
+	pm_runtime_resume(device);
+	return 0;
+}
+
 static int mei_me_pci_suspend(struct device *device)
 {
 	struct pci_dev *pdev = to_pci_dev(device);
@@ -396,7 +402,17 @@ static int mei_me_pci_resume(struct device *device)
 
 	return 0;
 }
-#endif /* CONFIG_PM_SLEEP */
+
+static void mei_me_pci_complete(struct device *device)
+{
+	pm_runtime_suspend(device);
+}
+#else /* CONFIG_PM_SLEEP */
+
+#define mei_me_pci_prepare NULL
+#define mei_me_pci_suspend NULL
+
+#endif /* !CONFIG_PM_SLEEP */
 
 #ifdef CONFIG_PM
 static int mei_me_pm_runtime_idle(struct device *device)
@@ -499,6 +515,8 @@ static inline void mei_me_unset_pm_domain(struct mei_device *dev)
 }
 
 static const struct dev_pm_ops mei_me_pm_ops = {
+	.prepare = mei_me_pci_prepare,
+	.complete = mei_me_pci_complete,
 	SET_SYSTEM_SLEEP_PM_OPS(mei_me_pci_suspend,
 				mei_me_pci_resume)
 	SET_RUNTIME_PM_OPS(