Monthly Archives: March 2015

Bringing sanity back to my T440s

Published / by mario / 4 Comments on Bringing sanity back to my T440s

As a long time Thinkpad’s trackpoint user and owner of a Lenovo T440s, I always felt quite frustrated with the clickpad featured in this laptop, since it basically ditched away all the physical buttons I got so used to, and replace them all with a giant, weird and noisy “clickpad”.

Fortunately, following Peter Hutterer’s post on X.Org Synaptics support for the T440, I managed to get a semi-decent configuration where I basically disabled any movement in the touchpad and used it three giant soft buttons. It certainly took quite some time to get used to it and avoid making too many mistakes but it was at least usable thanks to that.

Then, just a few months ago from now, I learned about the new T450 laptops and how they introduced again the physical buttons for the trackpoint there… and felt happy and upset at the same time: happy to know that Lenovo finally reconsidered their position and decided to bring back some sanity to the legendary trackpoint, but upset because I realized I had bought the only Thinkpad to have ever featured such an insane device.

Luckily enough, I recently found that someone was selling this T450’s new touchpads with the physical buttons in eBay, and people in many places seemed to confirm that it would fit and work in the T440, T440s and T440p (just google for it), so I decided to give it a try.

So, the new touchpad arrived here last week and I did try to fit it, although I got a bit scared at some point and decided to step back and leave it for a while. After all, this laptop is 7 months old and I did not want to risk breaking it either :-). But then I kept reading the T440s’s Hardware Maintenance Manual in my spare time and learned that I was actually closer than what I thought, so decided to give it a try this weekend again… and this is the final result:

T440s with trackpoint buttons!

Initially, I thought of writing a detailed step by step guide on how to do the installation, but in the end it all boils down to removing the system board so that you can unscrew the old clickpad and screw the new one, so you just follow the steps in the T440s’s Hardware Maintenance Manual for that, and you should be fine.

If any, I’d just add that you don’t really need to remove the heatskink from the board, but just unplug the fan’s power cord, and that you can actually do this without removing the board completely, but just lifting it enough to manipulate the 2 hidden screws under it. Also, I do recommend disconnecting all the wires connected to the main board as well as removing the memory module, the Wifi/3G cards and the keyboard. You can probably lift the board without doing that, but I’d rather follow those extra steps to avoid nasty surprises.

Last, please remember that this model has a built-in battery that you need to disable from the BIOS before starting to work with it. This is a new step compared to older models (therefore easy to overlook) and quite an important one, so make sure you don’t forget about it!

Anyway, as you can see the new device fits perfectly fine in the hole of the former clickpad and it even gets recognized as a Synaptics touchpad, which is good. And even better, the touchpad works perfectly fine out of the box, with all the usual features you might expect: soft left and right buttons, 2-finger scrolling, tap to click…

The only problem is that the trackpoint’s buttons would not work that well: the left and right buttons would translate into “scroll up” and “scroll down” and the middle button would simply not work at all. Fortunately, this is also covered in Petter Hutterer’s blog, where he explains that all the problems I was seeing are expected at this moment, since some patches in the Kernel are needed for the 3 physical buttons to become visible via the trackpoint again.

But in any case, for those like me who just don’t care about the touchpad at all, this comment in the tracking bug for this issue explains a workaround to get the physical trackpoint buttons working well right now (middle button included), simply by disabling the Synaptics driver and enabling psmouse configured to use the imps protocol.

And because I’m using Fedora 21, I followed the recommendation there and simply added psmouse.proto=imps to the GRUB_CMDLINE_LINUX line in /etc/default/grub, then run grub2-mkconfig -o /boot/grub2/grub.cfg, and that did the trick for me.

Now I went into the BIOS and disabled the “trackpad” option, not to get the mouse moving and clicking randomly, and finally enabled scrolling with the middle-button by creating a file in /etc/X11/xorg.conf.d/20-trackpoint.conf (based on the one from my old x201), like this:

Section "InputClass"
        Identifier "Trackpoint Wheel Emulation"
        MatchProduct "PS/2 Synaptics TouchPad"
        MatchDriver "evdev"
        Option  "EmulateWheel"  "true"
        Option  "EmulateWheelButton" "2"
        Option  "EmulateWheelInertia" "10"
        Option  "EmulateWheelTimeout" "190"
        Option  "Emulate3Buttons" "false"
        Option  "XAxisMapping"  "6 7"
        Option  "YAxisMapping"  "4 5"
EndSection

So that’s it. I suppose I will keep checking the status of the proper fix in the tracking bug and eventually move to the Synaptic driver again once all those issue get fixed, but for now this setup is perfect for me, and definitely way better than what I had before.

I only hope that I hadn’t forgotten to plug a cable when assembling everything back. At least, I can tell I haven’t got any screw left and everything I’ve tested seems to work as expected, so I guess it’s probably fine. Fingers crossed!

Building a SNES emulator with a Raspberry Pi and a PS3 gamepad

Published / by mario / 12 Comments on Building a SNES emulator with a Raspberry Pi and a PS3 gamepad

It’s been a while since I did this, but I got some people asking me lately about how exactly I did it and I thought it could be nice to write a post answering that question. Actually, it would be a nice thing for me to have anyway at least as “documentation”, so here it is.

But first of all, the idea: my personal and very particular goal was to have a proper SNES emulator plugged to my TV, based on the Raspberry Pi (simply because I had a spare one) that I could control entirely with a gamepad (no external keyboards, no ssh connection from a laptop, nothing).

Yes, I know there are other emulators I could aim for and even Raspberry specific distros designed for a similar purpose but, honestly, I don’t really care about MAME, NeoGeo, PSX emulators or the like. I simply wanted a SNES emulator, period. And on top of that I was quite keen on playing a bit with the Raspberry, so I took this route, for good or bad.

Anyway, after doing some investigation I realized all the main pieces were already out there for me to build such a thing, all that was needed was to put them all together, so I went ahead and did it. And these are the HW & SW ingredients involved in this recipe:

Once I got all these things around, this is how I assembled the whole thing:

1. Got the gamepad paired and recognized as a joystick under /dev/input/js0 using the QtSixA project. I followed the instructions here, which explain fairly well how to use sixpair to pair the gamepad and how to get the sixad daemon running at boot time, which was an important requirement for this whole thing to work as I wanted it to.

2. I downloaded the source code of PiSNES, then patched it slightly so that it would recognize the PS3 DualShock gamepad, allow me define the four directions of the joystick through the configuration file, among other things.

3. I had no idea how to get the PS3 gamepad paired automatically when booting the Raspberry Pi, so I wrote a stupid small script that would basically wait for the gamepad to be detected under /dev/input/js0, and then launch the snes9x.gui GUI to choose a game from the list of ROMS available. I placed it under /usr/local/bin/snes-run-gui, and looks like this:

#!/bin/bash

BASEDIR=/opt/pisnes

# Wait for the PS3 Game pad to be available
while [ ! -e /dev/input/js0 ]; do sleep 2; done

# The DISPLAY=:0 bit is important for the GUI to work
DISPLAY=:0 $BASEDIR/snes9x.gui

4. Because I wanted that script to be launched on boot, I simply added a line to /etc/xdg/lxsession/LXDE/autostart, so that it looked like this:

@lxpanel --profile LXDE
@pcmanfm --desktop --profile LXDE
@xscreensaver -no-splash
@/etc/sudoers.d/vsrv.sh
@/usr/local/bin/snes-run-gui

By doing the steps mentioned above, I got the following “User Experience”:

  1. Turn on the RPi by simply plugging it in
  2. Wait for Raspbian to boot and for the desktop to be visible
  3. At this point, both the sixad daemon and the snes-run-gui script should be running, so press the PS button in the gamepad to connect the gamepad
  4. After a few seconds, the lights in the gamepad should stop blinking and the /dev/input/js0 device file should be available, so snes9x.gui is launched
  5. Select the game you want to play and press with the ‘X’ button to run it
  6. While in the game, press the PS button to get back to the game selection UI
  7. From the game selection UI, press START+SELECT to shutdown the RPi
  8. Profit!

Unfortunately, those steps above were enough to get the gamepad paired and working with PiSNES, but my TV was a bit tricky and I needed to do a few adjustments more in the booting configuration of the Raspberry Pi, which took me a while to find out too.

So, here is the contents of my /boot/config.txt file in case it helps somebody else out there, or simply as reference (more info about the contents of this file in RPiConfig):

# NOOBS Auto-generated Settings:
hdmi_force_hotplug=1
config_hdmi_boost=4
overscan_left=24
overscan_right=24
overscan_top=16
overscan_bottom=16
disable_overscan=0
core_freq=250
sdram_freq=500
over_voltage=2

# Set sdtv mode to PAL (as used in Europe)
sdtv_mode=2

# Force sound to be sent over the HDMI cable
hdmi_drive=2

# Set monitor mode to DMT
hdmi_group=2

# Overclock the CPU a bit (700 MHz is the default)
arm_freq=900

# Set monitor resolution to 1280x720p @ 60Hz XGA
hdmi_mode=85

As you can imagine, some of those configuration options are specific to the TV I have it connected to (e.g. hdmi_mode), so YMMV. In my case I actually had to try different HDMI modes before settling on one that would simply work, so if you are ever in the same situation, you might want to apt-get install libraspberrypi-bin and use the following commands as well:

 $ tvservice -m DMT # List all DMT supported modes
 $ tvservice -d edid.dat # Dump detailed info about your screen
 $ edidparser edid.dat | grep mode # List all possible modes

In my case, I settled on hdmi_mode=85 simply because that’s the one that work better for me, which stands for the 1280x720p@60Hz DMT mode, according to edidparser:

HDMI:EDID DMT mode (85) 1280x720p @ 60 Hz with pixel clock 74 MHz has a score of 80296

And that’s all I think. Of course there’s a chance I forgot to mention something because I did this in my random slots of spare time I had back in July, but that should be pretty much it.

Now, simply because this post has been too much text already, here you have a video showing off how this actually works (and let alone how good/bad I am playing!):

Video: Raspberry Pi + PS3 Gamepad + PiSNES

I have to say I had great fun doing this and, even if it’s a quite hackish solution, I’m pretty happy with it because it’s been so much fun to play those games again, and also because it’s been working like a charm ever since I set it up, more than half a year ago.

And even better… turns out I got it working just in time for “Father’s Day”, which made me win the “best dad in the world” award, unanimously granted by my two sons, who also enjoy playing those good old games with me now (and beating me on some of them!).

Actually, that has been certainly the most rewarding thing of all this, no doubt about it.

GStreamer Hackfest 2015

Published / by mario

Last weekend I visited my former office to attend the GStreamer hackfest 2015, along with other ~30 hackers from all over the world.

This was my very first GStreamer hackfest ever and it was definitely a great experience, although at the beginning I was really not convinced to attend since, after all, why bother attending an event about something I have no clue about?

But the answer turned out to be easy in the end, once I actually thought a bit about it: it would be a good opportunity both to learn more about the project and to meet people in real life (old friends included), making the most of it happening 15min away from my house. So, I went there.

And in the end it was a quite productive and useful weekend: I might not be an expert by now, but at least I broke the barrier of getting started with the project, which is already a good thing.

And even better, I managed to move forward a patch to fix a bug in PulseAudio I found on last December while fixing an downstream issue as part of my job at Endless. Back then, I did not have the time nor the knowledge to write a proper patch that could really go upstream, so I focused on fixing the problem at hand in our platform. But I always felt the need to sit down and cook a proper patch, and this event proved to be the perfect time and place to do that.

Now, thanks to the hackfest (and to Arun Raghavan in particular, thanks!), I’m quite happy to see that the right patch might be on its way to be applied upstream. Could not be happier about it! :)

Last, I’d like to thank to Samsung’s OSG, and specially to Luis, for having done a cracking job on making sure that everything would run smoothly from beginning to end. Thanks!