Hi, There are two reasons for this issue we found until now.
1. Bug 904544 - hold wakelock to make sure input devices event can be handle before suspend 2. https://docs.google.com/a/mozilla.com/drawings/d/1nT0WOW-Xgxp0oNzgRx7BOdxMBrDKf0cxDVfLXMeziA8/edit a. The power key handling from Gecko/Gaia didn't do wakelock protection well. (The pink and purple arrows didn't be protected by wakeloc,.) b. So if kernel didn't help to hold a wakelock with constant timeout during resuming state then power key handling may not be done before re-entering to suspend. Thanks, Sincerely yours. ----- 原始郵件 ----- 寄件者: "an" <novac.a...@gmail.com> 收件者: dev-b2g@lists.mozilla.org 寄件備份: 2013 9 月 4 星期三 上午 11:46:12 主旨: Re: [b2g] Wake-up phone If it's of any help, I just figured out that the phone wakes every time if I press the volume button immediately after the power button. On Wednesday, September 4, 2013 5:21:57 AM UTC+3, Marco Chen wrote: > ----- 原始郵件 ----- > > > Any news on this issue? > > > > On Monday, August 5, 2013 10:18:20 PM UTC+3, an wrote: > > > On Monday, August 5, 2013 5:25:17 AM UTC+3, Marco Chen wrote: > > > > > > > Hi, > > > > > > > > > > > > > > > > > > > > > > > > > > > > We are trying to look this bug on Helix project now. > > > > > > > > > > > > > > And the initial idea is that FxOS didn't have sufficient time for > > > changing the power state from 3 to 0 within 0.5 seconds. > > > > > > > > > > > > > > > > > > > > > > > > > > > > The suspect flow is > > > > > > > > > > > > > > > > > > > > > > > > > > > > a. Apps processor got a RPC message for power key event. > > > > > > > > > > > > > > b. Linux kernel is woken up and processed the early resuming process. > > > > > > > > > > > > > > c. During step b kernel hold a wake lock for 0.5 seconds and expect any > > > one to decide whether system should be woken up from power state 3 to 0. > > > > > > > > > > > > > > d. Gecko's input widget received a power key event from input device > > > then throw a runnable event to main thread for following works. > > > > > > > > > > > > > > e. Before main thread got this power key event ( then sending to > > > shell.js -> chrome event -> system app -> power Web API -> Gecko -> > > > Changing power state ), > > > > > > > > > > > > > > the 0.5 seconds is time out and system go into suspend again. > > > > > > > > > > > > > > > > > > > > > > > > > > > > So what we saw will be > > > > > > > > > > > > > > 1. pressing power key multi-times then device can be woken up. > > > > > > > > > > > > > > 2. Pluggin USB then device can be woken up. > > > > > > > > > > > > > > > > > > > > > > > > > > > > We tried to prove this and figure out the solution. > > > > > > > > > > > > That's the behavior I'm seeing and that's what I imagined it might happen > > as you describe it. Not being a developer the whole chain of events was a > > more abstract one ;) to me but when I press the power key the soft buttons > > light up for a second as if the phone wants to wake up but it somehow > > looses steam. > > > > > > Please keep me posted with your findings and eventual solutions. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Sincerely yours. > > > _______________________________________________ dev-b2g mailing list dev-b2g@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-b2g _______________________________________________ dev-b2g mailing list dev-b2g@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-b2g
