Hans, all, > > ... this. I don't know what these flags do (and reading SMART in there > > gives me more a 'uh-oh' feeling) > > On x86 the lines between runtime suspend and system-suspend are blurring > with technologies like "connected standby" and in general devices moving > to suspend2idle as system-suspend state, I guess this also applies to > modern smartphone platforms but I'm not following those closely. I'd guess so, too. I am not aware of any existing mechanism for that at the moment, though. If somebody does, please enlighten us. > The "SMART" bit is really not all that smart, SMART_PREPARE means that > the drivers pm prepare callback will return positive non 0 (e.g. 1) to > indicate that the device may not be kept in its runtime suspended > state when transitioning to system-suspend, otoh when the prepare > callback returns 0 and the SMART_PREPARE flag is set then *all* suspend/ > resume handling can be skipped during a system suspend. Thanks for the detailed explanation! Much appreciated. > > Looking at the open coded version you did for the designware driver, I > > wonder now if it is better to just leave it at driver level? Need to > > sleep over it, though. > > I myself was thinking in the same direction (leave the entire suspended > check at the driver level). So, I was giving it some more thoughts, and my feeling is to still apply this series with the review comments addressed. Plus, clearly mark the new 'is_suspended' flag and the helper function as *optional* to allow for driver specific solutions as well. The then-to-be-added documentation would state that it is mostly useful for seperated system suspend and runtime suspend. For more complex situations, custom solutions are accepted, too. Which means your patch for designware should be added to the series. My take is there are enough drivers out there already which can benefit from this new helper. If it turns out to be useless somewhen in the future, we can still remove it. What do you (and all others, of course) think? Thanks, Wolfram
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