mei: revamp mei reset state machine

1. MEI_DEV_RESETTING device state spans only hardware reset flow
while starting dev state is saved into a local variable for further
reference, this let us to reduce big if statements in case we
are trying to avoid nested resets

2. During initializations if the reset ended in MEI_DEV_DISABLED device
state we bail out with -ENODEV

3. Remove redundant interrupts_enabled parameter as this
 can be deduced from the starting dev_state

4. mei_reset propagates error code to the caller

5. Add mei_restart function to wrap the pci resume

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/pci-me.c

@@ -321,16 +321,14 @@ static int mei_me_pci_resume(struct device *device)
 		return err;
 	}
 
-	mutex_lock(&dev->device_lock);
-	dev->dev_state = MEI_DEV_POWER_UP;
-	mei_clear_interrupts(dev);
-	mei_reset(dev, 1);
-	mutex_unlock(&dev->device_lock);
+	err = mei_restart(dev);
+	if (err)
+		return err;
 
 	/* Start timer if stopped in suspend */
 	schedule_delayed_work(&dev->timer_work, HZ);
 
-	return err;
+	return 0;
 }
 static SIMPLE_DEV_PM_OPS(mei_me_pm_ops, mei_me_pci_suspend, mei_me_pci_resume);
 #define MEI_ME_PM_OPS	(&mei_me_pm_ops)