> > On Wed, 2012-09-19 at 13:27 +0100, James Bottomley wrote: > > I think we could do this with a couple of flags sitting inside struct > > device itself: one for pm state and capabilities defined at a generic > > level and one for device specific pm state. The latter would be for > > things like the door lock information which is very specific to CDs > > (although not specific to SCSI CDs). Alternatively, even if we can't > > use these capabilities at the generic pm level, we still need an > > internal state set of flags because power state stuff traverses the > > stack and struct device is the only universal object in that stack. > > FWIW the SATA Device Sleep support, which is currently only used (in a > patch which is pending) automatically as an extension of the AHCI link > power management, can also be triggered manually by a GPIO line; I've > got a platform where it's done with an ACPI call. I suspect we'll see > that kind of manual setup on a few embedded platforms too. > > If we're working on hooking this up through the device layers, perhaps > that's worth taking into consideration? > > -- Hi David, For SATA Device sleep, what's the appropriate time to set the Device sleep, this seems also part of runtime PM? Best regards! Jack -- 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