Hi, When I saw that Android WiFi stack turns on/off WiFi chip periodically, I was a little surprised.
Based on my understanding of SDIO, 802.11 and SoC, We usually let the WiFi chip into the power save mode when idle, then the firmware inside the WiFi chip will use 802.11 PS mode. After that, WiFi chip only notifies the host(primary CPU) when receiving unicast/broadcast packet. Many WiFi chip vendors already implemented the similar mechanism. Regarding to the SDIO controller, let it into 1-bit mode. You will save more power since the clock of SDIO controller stops. As long as the host controller can receive the interrupt from the card, and that interrupt can wake up the primary CPU, it is OK to stop the primary CPU. When we design the SoC, we certainly divide the SoC into several power/ clock domains. And there should be the power management unit to turn off most parts of the SoC. It wakes up the whole SoC when the certain event(timer timeout or interrupt) occurs. Leon On Jan 29, 1:11 am, "Justin (Google Employee)" <[email protected]> wrote: > This is not possible. In sleep mode the G1's primary CPU is turned > off. Maintaining the WiFi connection requires use of the primary CPU. > Therefore sleep mode and WiFi are incompatible. > > Cheers, > Justin > Android Team @ Google > > On Jan 28, 6:41 am, Thomas Iverson <[email protected]> wrote: > > > hi all , i found g1 will automatically turn off the wifi connection in sleep > > mode , maybe it's for battery saving or something what , but , i want to > > keep wifi connection alive > > i googled a lot and still don't get any useful solution , any help ? thanks > > a lot ! --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Beginners" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-beginners?hl=en -~----------~----~----~----~------~----~------~--~---
