On Fri, Aug 31, 2012 at 10:33:40AM -0400, Alan Stern wrote: > On Fri, 31 Aug 2012, Aaron Lu wrote: > > > v5: > > Add may_power_off flag to scsi device. > > Alan Stern suggested that I should not mess runtime suspend with > > runtime power off, but the current zpodd implementation made it not > > easy to seperate. So I re-wrote the zpodd implementation, the end > > result is, normal ODD can also enter runtime suspended state, but > > their power won't be removed. > > This looks good. I noticed only a few things: > > In patch 5/7, your implementation of may_power_off is written in such a > way that if the drive is already powered off when userspace clears the > flag, the drive is not automatically powered back on. Maybe this is > what you want? No, actually I didn't consider this. What about I do this when may_power_off is set to 0: In its store function, if the device is runtime suspended(which means it is in powered off state since may_power_off was 1 before this store call) I'll set the flag to 0 and then runtime resume this device. > > In patch 1/7 you call both scsi_autopm_get_device() and > scsi_autopm_put_device() twice in sr_check_events(). With a little > rewriting it should be possible to call them only once. Just replace > the "return events" lines with gotos. Thanks, will change this. > > What happens if you have an idle ZPODD with may_power_off clear? A > regular ODD would get runtime-suspended. In the same way, a ZPODD > should also be runtime-suspended but left at full power. Does patch > 7/7 work this way? It seems to, but I can't tell for sure. Yes, if may_power_off is cleared, d3 cold state will not be allowed, which means it won't be powered off. Thanks, Aaron -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
