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[Solved] Double tap stop working [answered]

asked 2017-06-11 22:40:52 +0300

Mr.Thumb gravatar image

updated 2017-06-24 16:08:09 +0300

My beloved Jolla (the first one) has problems, double tap to open screen do not work stable. Could it be the proximity sensor? I can open it with the power button but that just hang up the phone when it is in-coming call :( Anyone has some good idear what it could be ?

  1. I have cleaned the small contacts from the sensor with no change of problem
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The question has been closed for the following reason "the question is answered, an answer was accepted" by nthn
close date 2017-06-24 17:57:33.558204



Have you run CSD Tool yet?, also, you can check with mcetool to see that Double Tap to wake is set to 'proximity'.

If you don't know how to get to CSD Tool, go to Settings/About product/ and tap 5 or more times on the text next to 'Build' - 'Accept' - and you're now in CSD Tool.

If you don't have mcetool installed, in terminal, type this; pkcon install mce-tools. Once installed, in terminal again, type mcetool and hit enter - you get output of all settings within. Double tap should be set to 'proximity'.

fmotl ( 2017-06-12 02:12:52 +0300 )edit

is there any applied patches currently. in My phone also the double tap stopped working then removing auto rotate patch worked for me.

p_pahare ( 2017-06-12 09:29:16 +0300 )edit

Yes I check with mcetool and "Double-tap wakeup policy" is set to "proximity" so I guess is right

Mr.Thumb ( 2017-06-16 10:37:54 +0300 )edit

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answered 2017-06-12 11:01:01 +0300

spiiroin gravatar image

updated 2017-06-16 12:11:36 +0300

Double tap detection is disabled while proximity sensor is reporting that it is "covered" -> double tap does not work but power button does work -> suggests proximity sensor issues.

If display does not get turned on when there is an incoming call -> can also be explained by misbehaving proximity sensor.

Using power key to force display unblanking should not hang up the call - just silence the ringing. You should still be able to answer the call from pull down menu.

Some more info/pointers at


If cleaning the display / even the sensor does not help, you could try to manually adjust the parameters used by the dynamic thresholds algorithm by 1) wiping the sensor area clean 2) placing the phone in such place that the sensor is not obstructed by anything 3) then executing something like the steps below as root user:

# cd /sys/devices/virtual/input/input10
# grep . prx_raw_polling prox_th_*default

What one should have is:

prx_raw_polling < prox_th_min_default < prox_th_max_default < 1023

But instead there is (live example from my personal Jolla Phone with proximity sensor issues):

 622  < 526 < 907

Which does not add up (and the low/hight thresholds applied by the driver can leave the sensor stuck in the "uncovered" state).

After adjusting the prox_th_min_default to slightly larger value than the sensor reading in supposedly uncovered state:

# echo > prox_th_min_default 700

Some sanity hopefully returns to the sensor behavior.

Note: That these changes are not persistent. Rebooting returns things back to defaults.

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hmm.. I tried it the sensor goes from about 500 to 1023, and reacting to light and darkness, I set prox_th_min_default, as you said, I can not get double tap to work.

Mr.Thumb ( 2017-06-17 00:03:58 +0300 )edit

Another is the proximity sensor suppose to go from 0 (full light) -> 1024 (full darkness) ? Mine show 1023 at full darkness ans 1023 at full light ??

Mr.Thumb ( 2017-06-18 23:00:45 +0300 )edit

@ Mr.Thumb It measures how much of the ir pulse sent from the sensor is reflected back. So 1023 = all of the signal bounced back = fully covered ... 0 = none of the signal bounced back = nothing obstructs the sensor. The latter being theoretical number as the glass itself etc is going to cause some reflection -> the lower the uncovered value is the better the sensor can be expected to work. But getting fully saturated reading (1023) while the sensor is not covered basically means there is no chance the sensor can differentiate between covered vs. not covered.

spiiroin ( 2017-06-19 06:42:54 +0300 )edit

@spiiroin Ahh ok it IR not just light /dark sensor that explain it, because I haveing a lamp in front it ;) = 1023 .

But it still do not get my double tap working :..(

Mr.Thumb ( 2017-06-19 11:01:08 +0300 )edit

@Mr.Thumb Just fyi - The same sensor chip handles both proximity and ambient light... it alternates between "measure incoming light" (=als), "transmit ir pulses and measure reflected light" (=ps), and sleep cycles.

spiiroin ( 2017-06-19 12:08:06 +0300 )edit

answered 2017-06-13 09:46:58 +0300

Mr.Thumb gravatar image

@spiiroin Thanks for your help. I got it to work again. There was nothing wrong with proximity sensor it was software. I tried to do a su-devel - pkcon get-updates -> pkcon update, but it failed . Then I did a pkcon refresh -p -v , to re-fresh the pkg cache, and then pkcon get-updates -> pkcon update , now it worked. Did a re-boot and now double tap worked and everthing is honky-dory.

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@Mr.Thumb I'm skeptic about updating sw having any effect here. The sensor driver has not been changed since the sales start and the logic for basic functionality we're talking here has not changed that much either lately. But IIRC J1 does some sort of p-sensor auto-calibration on kernel driver load time. So it might have been the reboot after updating rather than the sw refresh itself that made the difference for you.

Also if there are dust/particles in the sensor hole underneath the glass - rotating the device / gently tapping the phone against palm can make things work again for a while. Similarly presence or removal of dirt/sweat/grease from top of the glass changes completely how the sensor "sees" the world.

spiiroin ( 2017-06-13 13:39:54 +0300 )edit

You are right it was NOT software ( happy I was for a while) the problem, today it has the same problem again, it sims like I can change the behaveur by hitting light at the sensor place (upper right corner) may I take it apart and clean/checking for badness would help !?

Mr.Thumb ( 2017-06-14 11:15:23 +0300 )edit

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Asked: 2017-06-11 22:40:52 +0300

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