On Tue, Nov 15, 2011 at 04:51:29PM +0800, Lin Ming wrote: > > This is not the right approach. You should look instead at > > scsi_dev_type_suspend() in scsi_pm.c. If the device is already runtime > > suspended then the routine should return immediately. > > How about below? > > diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c > index d329f8b..94b60bd 100644 > --- a/drivers/scsi/scsi_pm.c > +++ b/drivers/scsi/scsi_pm.c > @@ -20,6 +20,9 @@ static int scsi_dev_type_suspend(struct device *dev, pm_message_t msg) > struct device_driver *drv; > int err; > > + if (pm_runtime_suspended(dev)) > + return 0; > + Something to be careful about is there are different types of suspend states (PMSG_*). IIUC, runtime PM is using PMSG_SUSPEND. Other states may or may not be compatible with PMSG_SUSPEND expectations, so you can skip suspend operation if the newly requested state is PMSG_SUSPEND but otherwise the controller needs to be woken up and told to comply to the new state. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
