@AppLee It's a good theory. But, as you said, I'm not interacting with the phone. It's locked, sitting on a shelf. No notifications are coming in and the device isn't being touched.

I think there must be a service or background job that is causing the phone to "wake up" or adjust screen settings. Just need to track down what it is.

I have a follow-up question.

Using the above path I can change the brightness, but the screen only remains dimmed temporarily (about ten minutes). After that the screen brightens again.

The PinePhone has a brightness range from around 0 to 3000 and the system automatically resets the backlight to 943 after a period.

The "automatically adjust brightness" option is turned off under the battery/power settings.

What service would automatically brighten the screen while the phone is locked and not being used interactively?

@Vehi_MV said in Dimming the display without locking:

@guru
Hi. You can set the brightness of display from terminal.
For example if you want 50% brightness you can use the following command:
echo 50 > /sys/class/leds/lcd-backlights/brightness

In case anyone else finds this thread, this was very helpful, but the path isn't the same on my system. I'm running 20.04 on the PinePhone and the path for dimming/brightening the screen is:

/sys/devices/platform/backlight/backlight/backlight/brightness

Update: I found the solution. At least when using command line programs like mplayer.

UBports on the PonePhone seems to default to trying to use PulseAudio, which doesn't work. It needs to be using ALSA, but the regular user account selects the wrong ALSA device by default. For some reason the root user gets the right device.

I used the "aplay -l" command to get a list of local audio devices:

$ aplay -l
card 0: PinePhone
card 1: sun9ihdmi

It seems the regular user is selecting card 1 when it needs to be selecting card 0.

So to play audio with mplayer (or other audio players) I need to manually specify card 0. With mplayer that looks like this:

mplayer -ao alsa:device=hw=0 audio-file.mp3

I'm currently looking for a way to make this selection permanent and consistent for all audio players, but for now I can at least funnel audio through mplayer on my PinePhone.

I'm running UBports 20.04 on a PinePhone.

An issue I've run into is no applications are able to produce sound when run as the regular user, phablet. This means the settings panel, web browser, and terminal applications such as mplayer cannot produce sound. Even when the volume controls are at max, no sound comes out, either through the phone's speak or through headphones when they are plugged in.

However, audio does work when applications are run as the root user. If I run "sudo mplayer audio-file.mp3" I get sound, but just "mplayer audio-file.mp3" produces no sound.

I've checked and the phablet user is part of the audio group. And the /dev/dsp and /dev/dsp1 devices are present and grant write access to the audio group.

Anyone else running into this? Anyone have a suggested fix? I'm a bit puzzled why phablet can't produce audio but root can.

Update: I have found that copying data directly to /dev/dsp can cause noise to be produced. For example, running "cat sound.wav >> /dev/dsp" causes noise to be produced by the phone's speaker. So I can confirm my user has write access to the audio device. It just seems media apps and web browsers run as my user (phablet) are not able to properly get audio to output while root can.

I recently purchased a hub/dock in order to use my PinePhone as a low-powered portable computer.

When I plug the PinePhone, running Ubuntu Touch 20.04 into the dock the user interface crashes. Lomiri appears to try to re-launch, then crashes again, and this crash/launch cycle loops until the hub or monitor is unplugged.

I am briefly getting visible output on the monitor, so the connection is good, Lomiri just doesn't seem to be stable when an external monitor is present.

Is there any workaround for this? My keyboard and monitor work through the dock if no monitor is attached, it's just the desktop session crashes when an external monitor is present.

For those interested, I got Manjaro Plasma working with the dock and external monitor. It runs slowly and crashes often on the PinePhone as Plasma seems too heavy for the device, but it works with the dock. Ideally though, I'd like to get UT running with the dock configuration as the performance of the OS is much better.

The announcement says PinePhone and PineTab are updated independently. the images for PinePhone are still for 16.04.

What does "independently" mean, in a practical sense, for users? Will there be a 20.04 image for PinePhones? Is there a schedule if 20.04 is being ported? Is the PinePhone image effectively abandoned?

@lakotaubp Thank you. I'll keep running 16.04 on the PinePhone for now.

I know UBports 20.04 hasn't been officially released yet, but I'd like to start testing pre-release images of it on my PinePhone. Are there pre-built images anywhere I can download for it? I checked the official installer and the Devices page, but couldn't find any information on beta testing pre-release versions for this device.

@Stefano I am running Ubuntu MATE 17.04 on my PC. I've also tried other distros, including Linux Mint and MX Linux to rule out an OS-issue.

I've tried booting my phone into fastboot mode and my PC doesn't detect it as a device then. Haven't tried in Recovery mode.

Update: I looked up the instructions for recovery mode, but it requires that the PC can detect the phone in fastboot mode, which doesn't work for me. My OSes have no indication there is a device plugged in, even when using "lsusb" to see all connected devices.

If I'm going to update, I think it will have to be by editing something on the phone itself to get it to recognize UBport's updated images.