I have a board that has a Qualcomm Snapdragon 210 (MSM8909).
It's running a stock kernel (https://github.com/android-linux-stable/msm-3.18) with a Debian Stretch sysroot.
I got the sound working (by routing the DAI Frontends to the correct Backend) using the mixer_paths.xml file as an example, but I'm having some weird issues with Alsa and specific programs.
For instance, if I want to use the nrsc5 project (which uses libao for sound output), I got this error message and no sound at all:
[ 6285.810132] msm_pcm_playback_copy: wait_event_timeout failed
Same happens with mpd (using alsa with the default hw:0,0).
However, if I use mplayer, it works (I get some errors related to ctrl not found, but not big deal, I don't have a volume control in the end).
Same if I use aplay with wave files.
I tried to install pulseaudio and configure alsa as a default source, it "works", but it drops like crazy (and it doesn't use CPU at all). Mplayer says that
"Audio device got stuck!"
The kernel that I'm using should have a patch that Qualcomm released about an error handling the timeouts (I checked this).
A quick note on the errors that I receive about the ctrl not found: Seems that the driver doesn't expose the "substream runtime"s, or something like that. However, I can modify the volume using some amixer commands (similar to the ones used in the DragonBoard410c, but tweaked accordingly to the mixer_paths.xml)
I don't know what else to do, because some apps that I would like to run, don't work properly, and they should.
Thanks!
Related
I am building a kiosk application using webkitgtk on the raspberry pi 4.
This application will not be connected to the internet and all the html,css, javascript for the UI are all located on the local filesystem.
I am using buildroot to setup the Linux system, starting with the pi 4 defconfig provided in buildroot.
I have enabled all the packages needed to get webkitgtk running.
Also, the kiosk application has been tested on my desktop, using the same software stack and it works
However, when i try to launch the application on the raspberry pi, a blank page pops up. I have played around with the WebKitWebSettings object associated with my WebKitWebView by enabling local file access. It still shows up a blank screen.
Also included in my pi4 application bundle is a simple gtk3+ application. This launches successfully!
I will really appreciate some pointers as to why this is happening as i have sort of reached a dead end
UPDATE
I enabled the MiniBrowser app that comes with the Webkitgtk package.
Entering the local url, The page does not load. It only gives me a message at the top saying "Successfully downloaded".
It seems to be treating my input as a download
UPDATE 2
After some more experimenting, i was finally able to get webkitgtk working on the pi 4.
The problem seems to originate from using the webkit_web_view_load_uri() api.
It does not seem to recognize my html document as a web page.
I got around it using the webkit_web_view_load_html() call. This included some hacks by first reading in the contents of the html doc into a character buffer, and passing it to webkit_web_view_load_html().
You also have to provide a base path to this function call to be able to resolve all the urls (scripts, css, images etc) in your html document.
Another problem i haven't been able to work around is, SVG images are not loading in webkitgtk. I have used jpg formats and they work. I suspect this my be due to a configuration switch in building webkigtk
It's hard for me to figure out what might be happening without having access to your environment and settings. My gut feeling is that pages are showing blank because perhaps some shared libraries are missing. You can check that with:
$ ldd WebKitBuild/GTK/Release/bin/MiniBrowser
I am using buildroot to setup the Linux system, starting with the pi 4 defconfig provided in buildroot.
There's a buildroot repository for building WPE for RPi. WPE (WebPlatform for Embeded) is like WebKitGTK but doesn't depend on GTK toolkit. Another important difference is that WPE runs natively on Wayland.
If you're interested in having a webapp embedded in a browser running in a device with limited capabilities, WPE is a better choice than WebKitGTK. The buildroot repo for building WPE for RPi is here:
https://github.com/WebPlatformForEmbedded/buildroot
There's is also this very interesting step-by-step guide on how to build WPE for RPi3:
https://samdecrock.medium.com/building-wpe-webkit-for-raspberry-pi-3-cdbd7b5cb362
I'm not sure whether the buildroot recipe would work for RPi4. It seems to work for all previous versions, so you might be stepping in new land if you try to build WPE on RPi4.
If you have an RPi3 available I'd try to build WPE for RPi3 first, and make sure that works. Then try for RPi4.
I would like to make a Graphical interface for a home-made program using SFML on Raspberry Pi2. I am using Raspbian. I recompiled the graphical lib
It works fine unsing startx first, then using my application, which wors perfectly fine.
But I can't figure if it is possible or how to launch my application directly after boot without launching startx (just to optimise the cpu of the Raspberry).
Starting my program direcly after boot, I get the following error:
Failed to open X11 display: make sure the DISPLAY environnement variable is set correctly.
Aborted.
I already tested the classic export DISPLAY=:0.0 but without sucess.
I interested myself in x and xinit, but I am not sure that would even do it.
Where should I start looking? I don't need a complete solution, even a hint or an idea would be nice!
I checked to see if it was possible to open a graphical app without the X desktop environment and as that answer states, with Firefox at least, you need the X server which SFML also probably needs in order to create a window.
The answer states:
Basically something like:
$ X
Then you just start Firefox in this X server:
$ DISPLAY=:0 firefox
You can switch from the X server and the framebuffer by using
CTRL+ALT+F1 and CTRL+ALT+F7.
You could try that and see if it helps.
Also, still searching, I found a forum post on the sfml website about what you're trying to accomplish stating somewhere:
SFML requires OpenGL, so as far as I know you need at least X running,
but you probably don't need gnome, KDE or a similar Desktop
Environment on top.
The forum guy asking for help seems to have managed to get X11 and a SFML basic render window to work on Ubuntu server after someone posted a link to xinitrc. I guess, that's the route to go from here.
I can find nothing on how to do this. I am programming an Intel Edison in C and an Android phone in Java. I want to pair the Edison from the Android phone. I would think simple pairing (sspmode 1) would work but I get an error message on the phone about a wrong pin where no pin was requested. With sspmode 0 I get asked for a password but have no idea what it is as it is randomly generated in my NoInputNoOutput Edison. We have everything else working. If we pair from Edison manually, the rest of the code can connect and send bluetooth messages back and forth from the Edison to the phone. But pairing from Edison to any random phone that walks by is not acceptable. I think it is called Bluejacking.
I have seen some posts about using simple-agent but frankly what I understand is that BlueZ security changed so much between 4 and 5 that most all that I see doesn't work. I also see that the switch from 4 to 5 broke a lot of systems so I don't feel alone. I would try it but simple-agent is not on Edison and I have not found a procedure to install it. And as I don't know if the little I can find applies to version 5 as it all references version 4 I am feeling a little lost.
Can anyone point me in the right direction to something that will work on BlueZ 5? I am on 5.18.
The solution presented on the last post of this article does work
http://www.linuxquestions.org/questions/linux-wireless-networking-41/setting-up-bluez-with-a-passkey-pin-to-be-used-as-headset-for-iphone-816003/
Edit simple-agent, put it somewhere, make it executable, put the missing files in the same directory and run it. It must stay running for it to be active.
In my case, the missing file was bluezutils.py.
Run hciconfig hci0 sspmode 0 first
Pl use Bluz5.30.
Initially it was really difficult to bring up bluetooth using Bluez 5. It seems it was okay with Bluez 4.I have tried different versions of Bluez 5 on my LFS build. Even up to Bluez 5.28 it was not satisfactory. Now it is Bluz5.30, with this, LFS doc and lot of trail, I could manage. I feel Bluez is one of the most badly documented user unfriendly software. I also feel it is very buggy. It can hang machines forcing to hard boot the system. I have seen bluetooth forcing the Android phone also to reboot. So it is important to get the latest version of the software. But to make the bluetooth speaker work Pulseaudio was needed. It is better to get the latest version; here also LFS doc was fine.
So the process of connecting speaker was using bluetoothctl is as follows;
>> power on
>> scan on
>> pairable on
>> pair <device>
>> agent on
>> default-agent
Now the actual sound. Here pactl and pacmd are useful.
paplay -d can test the devices.
using pacmd with command 'list-sinks' can show the devices.
pacmd ->list-modules can show the modules loaded.
How to change automatically the audio output to bluetooth speaker when it is connected?
For me in one machine it was working fine, with an identical LFS in another machine it was not working. Finally it was identified as a
missing module module-device-manager with arg do_routing=1.
Once it was loaded everything was fine. This particular module was not shown in the pulse configurations. So I have to find that and load,
pacmd
load-module module-device-manager do_routing=1
One can add a line in the default configuration file available in /etc/pulse.or one can add it in the user configuration file also.Now to make the new bluetooth speaker being used to play sound. For that issue the command 'move-sink-input ' using pacmd. You can find the sink names my issuing the command 'list-sinks'.
If your speaker is not connecting, it may be that it is already connected elsewhere. If it is not so, remove-device; scan on; pair; and connect using bluetoothctl. I was worrying how to make file transfer using bluetooth (Bluez5). Actually very little information is available in LFS documention or in general in the NET. This very true and unfortunate about Bluez in general. They do not provide any real user doc or nothing is available in net. So the steps are as follows:
You need to install OBEX library. Then you build Bluez5 (if it not done already). It will install obexd. After installation you can find obexd in $PREFIX/libexec/bluetooth/obexd.This is where you find bluetoothd also. One generally makes a link for bluetoothd in /usr/sbin. A similar link can be made for obexd also. Once you start bluetoothd and obexd you can find object transfer profiles in bluetoothctl->show.If you need a phone to push objects to the computer, you need to run obexd with options '-a' and '-r '. if '-a' is not given phone will fail to send the file. Now how to push a file from Computer to Phone. For this you need obexctl, I do not think it is a finished tool, and it will not be installed while we build Bluez 5. I have seen it in the source tree and copied to /usr/bin/. It should be used to connect the Phone and when the connection is established one can 'send ' and you have to accept the request in the phone.
Starting obexd as a deamon was a problem. When obexd was tried on a text terminal (init 3) it was not possible to start since it needs a dbus session which in turn needs X display. It means one need to login an X seession before you start obexd. If you dissable X while building DBUS (--without-x) then Window Managers will not work. But there is solution with 'dus-run-session < command> [args]'. That means you can start a service obexd (like bluetoothd) in the system start-up. So just by switching on the Computer ( if pairing, trusting etc... was done earlier) one can push files from Phone to computer.
>> connect <device>
Second time onwards just connection is fine. Probably you can trust the device.
>> trust <device>
im making a C project for university in Linux, its basicaly a protocol for file transfer between 2 computers. The program works fine and it sends many files without any problem, but there is 1 or 2 files i have tested and the program just crashes without any report and i just dont know how to debug the problem. Any help would be appreciated.
I also dont know if i should post the code or not, because both files (application and protocol) have over 1.5k lines of code.
In most Linux Distributions the core dumping is disable by default (which can be viewed from the system resource limit "ulimit -c" will be zero if it is disabled). To enable the same, use "ulimi -c unlimited".
To add, in Ubuntu like modern distributions, they have customized program to send the report/core file to Ubuntu developers specified in "/proc/sys/kernel/core_pattern". Make sure to change it for development purpose to debug further.
You can even try "valgrind" or "gdb live debugging" to have more clarity about the problem.
I am a beginner to DBus and wrote one sample application using dbus but i am facing a weird problem. My app is running fine on guest os as Ubuntu (On virtual box with windows host ) but the same app is not working on standalone Ubuntu system (also tried on meego, no luck thr as well).
Then, i verified the obvious doubts on dbus, glib libraries versions. Its same on both the environments, and the issue is consistent. I mean the app always runs without any prob on virtual box and always crashes on the standalone ubuntu.
Here is the brief desc about the issue.
App is supposed to send 150 signals on dbus and another app is
receiving these signals. (No issues here in send & receive).
I have an array of DbusMessage[150] (also tried with the list of 150 DBusMessage)...appending the arguments on to the dbus msg and sending on to bus..one at a time...no looping...
The sequence of dbus APIs are all correct and verified by referencing multiple sample source code.
All of above works fine, but on the standalone ubuntu system, i can always see segmentation fault, on dbus_connection_send() call.
I reverified everypossible places where in "seg faults" can happen and it all looks fine to me. This is how i am appending my arg to dbus message.
dbus_message_append_args(pDbusMsg, DBUS_TYPE_ARRAY, DBUS_TYPE_BYTE, &pData, sizeof(pData),
DBUS_TYPE_INVALID) != TRUE)
then connection send..and then calling dbus_connection_flush(). Also as my app has to send the same message again (but not immediately), i am re registering the same signal by calling dbus_message_new_signal()..i have verified all the pointers / memory / dbusmessage..everything looks fine and works fine on virtualized ubuntu os.
Just to add, i tried sending with dbus_connection_send_preallocated() and it works fine for few messages(10-15~), but not consistent enough.
Have you ever had this kind of issue, please let me know any clue to solve this prob....Any help would be appreciated or any examples/tutorials as well taking into consideration I'm just starting out with dbus :P
Thanks
I dont know if you have heard about dbus related debugging tools. For beginning you can try calling the exposed functions using some dbus-debugging-tool. If it doesnt throw segmentation fault when you call using the tool, then probably you should look for issues in your code. Otherwise you should check things related to environment.
One such tool is - DFeet
Another such debugger(commandline based) is provided by Qt people as well.