[Nexus 6  Original Android Development] wrongway213:
[MENTION=3795148]neobuddy89[/MENTION] I have stumbled upon what I believe may be some pretty significant information. It is not a bug in the kernel at all, but a setting in Synapse that is defaulted in a way I believe may be causing some pretty serious issues for users, specifically during phone calls. I had been dropping calls constantly on the right radio and APN on multiple ROMs, finally I took a log and as I had no idea what the issue was, I did no even know who to submit it to. A friend on the forum I asked what to do in such a situation reached out to a kind developer who took a look at the log, and the conclusion was reached that the issue may lie in the kernel, and that the solution may be to enable sensor_ind wakelock in Synapse and reboot my device. After having done this, I have made and received numerous phone calls since. I have dropped a single one of them, and it was a little over an hour into the call at that point - prior to enabling sensor_ind I could make it maybe 3 minutes into a call if I got lucky, sometimes not a full minute. That was the very first call I made after enabling sensor_ind. I have dropped no other calls since then. To note, I have had ambient display disabled throughout this whole process and still do. I have changed nothing else whatsoever in my setup and have had this issue of calls dropping on multiple ROMs ever since the Google Play Store 5.4.10 update.

I have thus concluded that Google has finally done what everyone believed they had done when 5.1 was introduced and completely and totally fixed sensor_ind wakelock issues. I caught sensor_ind acting up with ambient display disabled after upgrading to 5.1 on a clean install of Benzo ROM with leanKernel on 5.1 bootloader and radio when 5.1 first launched and reported it to Imoseyon, so I am also quite convinced that Google had not actually fixed the wakelock on initial 5.1 release. I am not able to create a situation in which I can replicate the behavior of this wakelock acting up when ambient display is enabled any longer, and if it was an issue still I believe I could - I was very involved in the process of trying to push for elimination of that wakelock across kernels for our device as it caused my device serious issues. The only reasonable conclusion that I or any of the other users I spoke to could reach is that disabling the sensor_ind wakelock at this point in time is directly correlated with dropping phone calls. Here's a link to the post in which I attached a log of the call dropping, which is right in the middle of the conversation about said issue. I am of the opinion that defaulting this wakelock to enabled could potentially save a lot of users a lot of issues, especially given the sometimes unpredictable nature of Synapse settings sticking or setting on boot. My apologies for the novel of a post - I could not accurately explain the issue and the conclusion that has been reached without being thorough. Here is the post in which the issue is being discussed and my log is attached (filtered for "incall") - I hope that this information is helpful. http://xdaforums.com/showpost.php?p=60012257&postcount=165