urfkill : a daemon to centrally control RF killswitches

Here's another project of the u-daemon variety. The latest addition to upower, udev, etc. Meet urfkill.

urfkill is meant to be a daemon that centralizes killswitch handling, rather than having all kind of different applications and daemon handle Wi-Fi, Bluetooth, WWAN and whatnot separately, and potentially fighting over them, you can have just one system that tracks the states and makes it possible to switch just one type of killswitch on all at one, or turn everything off should you so desire...

One reason I've taken an interest in urfkill in Ubuntu is that as we build a phone, we have to keep thinking about how users of the devices will be mobile. That's even more the case when you think about a phone or tablet than a laptop: on a laptop, you may have to think of WiFi and Bluetooth, but you're just about as likely to have your laptop off or not have it at all; whereas phones and tablets have become ubiquitous in our way of life.

Like anyone, thinking mobile I'd first think of walking around, driving, or other methods of travel. Granted, nobody needs to turn off Wi-Fi when getting in their car, but what about on planes?

This is the first thing everything brings up when talking about killswitches. Planes. Alright, you really do need to turn the device off on take off and landing, but some airlines do now allow wifi to be on and offer in-flight service. They still require you to keep cellular and bluetooth off. Also, while I sometimes do take my laptop out of my bag on long flights, it's just cramped. Space is at a premium on a flight (hey, I fly economy...), you'll likely want to have a drink, people besides you may need to get up, spillage could occur if there is turbulence...

I don't really enjoy using my laptop on a flight, even though it's quite small. It's just so much trouble and not very comfortable.

However, I do love to watch saved movies, listen to music, and play games on a tablet. That tablet will most likely need to have radios turned off. My phone will typically just stay off and stowed far enough, since I don't really change SIM cards until I can do so safely without risking to lose the thing.

But then, one can also think of how you should avoid using transmitting equipment in a hospital. They have similar rules about radios as planes to avoid interfering with cardiac stimulators, MRI equipment, etc.

Having all kind of different applications handle each type of killswitches separately is quite risky and complicated. How are you certain that things have been turned off? How do you check in the UI whether it's the case? Can you see it quickly by scanning the screen?

What about the actual process of switching things off? Do you need to go through three different interfaces to toggle everything? What do you need to do if you don't have a physical switch to use?

What about persistence after a reboot?

urfkill is meant to, in time, address all such questions. At the moment, it still needs a lot of work though.

I've spent the last day fixing bugs I could find while testing urfkill on my laptop, as well as porting it to logind (still in progress). In time, we should be able to use it efficiently in Ubuntu to handle all the killswitches. With some more work, we will also be able to use it to manage the modem and other systems on Touch.

For the time being, urfkill is available in the archive, for those who want to start experimenting with it.

Hacking with a Samsung ARM Chromebook on Trusty

So I decided it was about time to update / reinstall my Samsung Chromebook (the ARM one...) to Trusty, or at least to use Saucy. Turns out it's not that simple.

First, you need to know where to get the right stuff. I installed straight on the device, so chrUbuntu was the obvious choice. It's a pretty nice script that allows you to do just about anything necessary.

1) Bring your Chromebook to developer mode.

I'm not going to give the details. It's findable on the Internet, and unsafe enough that you should only do this if you know what you're doing... That counts double for running Trusty on the Samsung Chromebook.

From there, get into crosh (Ctrl+Alt+T), in shell mode (type shell at the crosh prompt).

2) Download the script:

cd ~/Downloads
wget http://goo.gl/s9ryd

3) Run the script:

sudo bash s9ryd xubuntu-desktop dev

This will do the gory install step, partition your device and format the new partition, download the ubuntu core tarball, and from there install the metapackage you've asked for as a first argument.

Be aware that if you have never repartitioned the device, you'll likely notice the system rebooting during the process -- if that happens, just re-run the same command to pick this back up where they ended. It's clear when the process is done and the system installed -- the script requires you to press Enter to reboot.

This was where things got fun.

Turns out my device booted fine into Trusty, but it would only show a black screen with the mouse cursor. If you moved the mouse, you could see the cursor changing but still nothing else. Switching to another VT (Ctrl-Alt-arrow (F1) or whatnot) would work to get you a text-mode login, but only if you switched early enough while X was getting ready to load... otherwise, you'd just get a pretty garbled display.

I hacked at the whole thing for a good while. I already know xf86-video-armsoc was involved in ChromeOS at some point, so I tried to install that.

Still no love. Tried to copy the libs from ChromeOS to the device, in case it was some libmali or EGL/GLES issue... Still nothing better.

I even touched /etc/X11/xorg.conf with some black magic, looking up the details using w3m in a text console...

Turns out the problem was with xf86-video-armsoc itself. I initially clued in when I looked at the dates for upload of the X packages and xf86-video-armsoc itself -- it didn't seem quite right: X was newer by a bit. I knew there could be some issue with the ABI in some cases; but after more careful investigation, that's probably fine too -- armsoc properly depends on -abi-14.

After much more work and trial and error, I updated xf86-video-armsoc to 0.6.0 from the Linaro git tree and also reverted one commit changing flags and it's not mostly working. X runs, I get lightdm, I can run apps -- "compositing" in Xubuntu works too, to get transparency and gradients... all with some minimal display corruption of the window decorations.

So the end of the line is -- if you want to run Trusty on your Chromebook and run into similar black screen issues, and you feel daring, feel free to try my newly-built xf86-video-armsoc package in my PPA:

https://launchpad.net/~mathieu-tl/+archive/ppa/+sourcepub/3627079/+listing-archive-extra

It's simple; once you're in a text console on the machine (login as user/user):

nmcli dev wifi connect <your wifi network> password <your wifi password>
sudo add-apt-repository ppa:mathieu-tl/ppa
sudo apt-get update
sudo apt-get install xserver-xorg-video-armsoc-exynos
sudo reboot

These updated packages, or at least some kind of permanent fix, should make it into Trusty soon. Stay tuned :)

Implementing MTP on Ubuntu Touch

Some of the fun parts of working at Canonical is how you get to work on so many different things.

I've spent the last few days working on an implementation of the MTP protocol for Ubuntu Touch, based on some amazing initial work from Thomas Voß to port the Android MTP libraries to C++.

I hadn't touched C++ in just about ten years. Last time was for school stuff, and it seems like things have changed a fair amount since, so I first had to get back in touch with the quirks of C++, learning Qt (which I used for my initial work), and learning Boost; in particular Boost::Filesystem, and some of the most fun pieces of Boost like BOOST_FOREACH, range adaptors, etc.

But MTP has been progressing very nicely, with code surely ready to land pretty soon in the Touch images. It was initially only exposing image files in /home/phablet/Pictures, but the latest code (still at lp:~mathieu-tl/mtp/images) now exposes all files in /home/phablet.

Not everything is implemented yet: for instance, you won't really have access to see or change permissions, copy or move files around the exposed filesystem, or delete files, but you can already browse and retrieve files, just like you can use the current MTP code to push files to an Ubuntu Touch device.

I'm thrilled at what's to come on that front, this is going to be a lot of fun.

If you're interested in testing this, feel free to take a copy of my bzr branch and experiment. You can build mtp simply:

cd mtp/

sudo apt-get install bzr bzr-builddeb debhelper build-essential cmake libboost-dev libboost-filesystem-dev

bzr bd

Let's keep working on making Ubuntu and the Touch images rock!

Protocol stacks on Ubuntu Touch

We're working really hard to get the Ubuntu Touch images into a state where the UI is really polished, the experience rocks, and just to make it a truly amazing product that reflects the core principles of Ubuntu.

One of the aspects of this work is to get to a really good story with protocol stacks in general -- that is to say, bluetooth, WiFi, and the fun things behind connectivity on a mobile device. How can I get my files on the device? How can I copy the pictures that I've just taken back to my computer?

On the way back home from Oakland I've had quite a lot of time to reflect on what we've done so far. I've seen really cool demos of things you could get done on Touch and how things are going to look like in the near future. It makes me very proud to be part of getting Ubuntu to a large number of people through a solid Desktop system, but also stellar mobile devices support.

So, we did get bluetooth to work pretty okay so far on Touch. It seems like the current baddest issue is really just UI, but fortunately people are already hard at work fixing that, too. Keyboards can be discovered, and so can mice (I've uploaded a video to YouTube about that before). Bluetooth headsets should follow soon, but when I last tried I was running into issues with pulseaudio on the Nexus 7... If you're interested in bluetooth and know a little about BlueZ and the command line, by all means, let me know on IRC and let's get this to be really awesome.

For WiFi, we also have indicator-network in the archive, all rewritten, received tons of love, and soon to be ready to shine on both the desktop and mobile phones or tablets. Don't get me wrong, there's still a long way to go, but it feels to me like one thing we can pretty quickly ramp up to converge and essentially be the same experience no matter what form factor it is running on.

That covers WiFi -- but what about mobile data? (3G / 4G, but I rather speak of it in the most general terms) Well, that's being actively worked on as well. We're not too far off from having working 3G data  on the "officially supported" devices (Galaxy Nexus, Nexus 4, Nexus 7); and from there it seems like it may not be too much trouble for people to ramp up that support for other devices. Sure, it's complicated work because of how technical it is, but I think it's still approachable.

For mobile data, I've lately been working on teaching NetworkManager to speak to oFono; which are the two stacks we're decided, at UDS, to use to handle networking and telephony. The code itself isn't too pretty yet, but I'll add just a bit more meat to it and provide it as a test bzr branch for people to experiment with, until it's stable enough to make it into the archive altogether.

All this to mention that I'm really excited about the current progress for Touch, and although my progress on my own work items wasn't exactly stellar, I'm thrilled about what's to come. So thrilled I'll contact my cell provider to get the right SIM card size to start using Touch on a Nexus 4 as my main phone next week.

See you all at virtual UDS, looking forward to lots of constructive discussions about networking and connectivity!