diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c index d329f8b12e2b..a633076e5622 100644 --- a/drivers/scsi/scsi_pm.c +++ b/drivers/scsi/scsi_pm.c @@ -49,8 +49,22 @@ static int scsi_bus_suspend_common(struct device *dev, pm_message_t msg) { int err = 0; - if (scsi_is_sdev_device(dev)) + if (scsi_is_sdev_device(dev)) { + /* + * sd is the only high-level SCSI driver to implement runtime + * PM, and sd treats runtime suspend, system suspend, and + * system hibernate identically (but not system freeze). + */ + if (pm_runtime_suspended(dev)) { + if (msg.event == PM_EVENT_SUSPEND || + msg.event == PM_EVENT_HIBERNATE) + return 0; /* already suspended */ + + /* wake up device so that FREEZE will succeed */ + pm_runtime_resume(dev); + } err = scsi_dev_type_suspend(dev, msg); + } return err; }