On Sat, Aug 17, 2013 at 7:53 AM, Rafael J. Wysocki <r...@sisk.pl> wrote: > On Friday, August 16, 2013 05:13:42 PM Li Yang-R58472 wrote: >> >> 在 2013-8-16,下午7:22,"Rafael J. Wysocki" <r...@sisk.pl> 写道: >> >> > On Friday, August 16, 2013 04:06:26 PM Li Yang wrote: >> >> Hi Guys, >> >> >> >> Is there a standard way for the device drivers to know if the system >> >> is going to “standby” mode or “mem” mode when the suspend() callbacks >> >> are called? >> > >> > No, there's none. >> > >> > What do you need that for? >> >> Some chips like ours are putting the on-chip devices into different low >> power states when entering different system low power states. When we enter >> system standby, on-chip devices are clock gated. While entering suspend to >> ram, on-chip devices are power gated. We want to driver to act differently >> too when entering different suspend states. > > Can you possibly use platform suspend operations to implement that (in analogy > with ACPI suspend operations)?
I agree it's best to get the state that the device will be in during suspend from the platform code. Will it be better to have a standard interface to pass this information? Given the fact that a single device can be used by different platforms even different architecture nowadays. How about exposing some new callbacks from the platform_suspend_ops for the driver to use? Regards, Leo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/