On 08/17/2012 12:19 AM, Dani Camps wrote
I am working on a research project, and our intention is to study the effect that the Wi-Fi radio has on the battery life of an Android mobile phone. In particular we would like to be able to configure the wi-fi radio to stay "awake" for a certain time period and "sleeping" for other time periods, and then study how the length of these intervals affects battery lifetime. From your answer, I understand that we cannot control exactly the power state of the chipset, but I wanted to check with you whether the following approach might work: 0- We let the mobile device associate with an Access Point. 1- When we want the chipset to stay awake, we send from the driver a PM_OFF configuration command to the chipset. What I expect it would happen is that the chipset sends a packet to the AP with PM=0, and stays awake all the time. 2- When we want to send the chipset to sleep, we send from the driver a PM_MAX configuration command to the chipset. What I expect it would happen is that the chipset sends a packet to the AP with PM=1, and goes to sleep. Now, IF we can guarantee that there is no traffic to/from the mobile device during the time that we want the chipset to be sleep, then the chipset will indeed be sleeping *most* of the time. The only exception will be that the chipset will regularly wake up to catch a Beacon frame, but probably it is also possible to configure how often that happens, and thus the effect on our measurements is not large. Do you think the previous method is sound?
Your approach looks good. I think that's the best we can do. ;) Franky -- 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
