On 01/09/2012 08:34 AM, Guy, Wey-Yi wrote: > On Mon, 2012-01-09 at 09:01 +0800, Yan, Zheng wrote: >> On 01/06/2012 05:47 PM, Johannes Berg wrote: >>> [add linux-wireless] >>> >>> On Fri, 2012-01-06 at 10:41 +0800, Yan, Zheng wrote: >>>> This simple patch adds open/close based runtime PM support to the iwlwifi driver. >>>> Namely, make the driver suspend the device after shutting down the interface and >>>> resume the device when activating the interface. In my test, suspending the device >>>> can save about 0.4 watt power. The shortcoming is that the device no longer generate >>>> rfkill changes interrupt. >>> >>> NACK due to that last sentence. There's no way we can live with that in >>> the general case -- and your patch isn't even configurable afaict. And >>> I'm sure polling the rfkill flag would use just as much energy. >>> >> It's configurable, runtime PM is disabled by default. > > Somehow I miss it, how you configure it? > change the value of /sys/devices/.../power/control to auto to enable the runtime PM. (e.g echo auto > /sys/devices/pci0000:00/0000:00:1c.3/0000:02:00.0/power/control) >> >>> There might be some value in this in a system that doesn't have a hard >>> rfkill line, but that means this needs to be configurable since the >>> device can't know whether there's a button or not [1]. >>> >> The patch targets system that only use software rfkill > > How you control that? I can't. Our team is working on runtime PM project, the purpose of the patch is more or less to demonstrate how much power can be saved. Regards Yan, Zheng -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
