Re: [PATCH v3 3/6] [SCSI] runtime resume device before system suspend

Hello,

On Thu, Nov 24, 2011 at 2:54 PM, Alan Stern [off-list ref] wrote:

Therefore, when entering the SUSPEND or HIBERNATE stages of system
sleep, we can skip the callback to the driver if the device is already
in runtime suspend.  When entering the FREEZE stage, however, we should
first issue a runtime resume.  The overhead of doing this is
negligible, because a suspended drive would be spun up during the THAW
stage of hibernation anyway.

My brain is half fried at the moment so maybe you're saying the same
thing, but I hope this is something simple. Like...

    /* for libata runtime suspend is equivalent to suspend */
    if (runtime suspended && target == SUSPEND) {
        yeah! skip drive pm ops;
    } else {
        end runtime pm;
        ask EH to enter target PM state;
    }

I really don't think we need to optimize this further than this.

Thanks.

-- 
tejun