I've followed the instrucions here to install the wolfson sound card drivers in pi with raspbian and all seemed good (kind of, good a couple of messages saying that some files didn't exist, but followed stuff posted on the same page and "think" they were solved) and Pd can see the sound card (it should be the snd_rpi_wsp (hardware), right?) but doesn't produce any sound and I get this error message audio I/O stuck... closing audio whenever I set it as the audio device and whenever I turn audio on.

It does make sound though through its built-in sound card, but very soft. Can anyone point out how to install the drivers for raspbian?

Cheers

@alexandros Here's my note, hope it helps:

1. install on sd-card raspbian distribution
   (http://downloads.raspberrypi.org/raspbian/images/raspbian-2014-01-09/)
   using http://sourceforge.net/projects/win32diskimager/files/latest/download
   1.1) pi / raspberry = sudo rpi-update
   1.1.1) sudo raspi-config (overclock, expand sd-card, enable camera)
   1.1.1.1) sudo apt-get update / upgrade / dist-upgrade

2. recompile the kernel with the rt/wolfson driver:
   http://www.talkunafraid.co.uk/2014/04/real-time-kernels-and-audio-on-the-raspberry-pi/
   sudo apt-get install bc libncurses5-dev libusb-dev
   wget http://downloads.element14.com/wolfson/wolfson_drivers.tar.gz
   tar zxf wolfson_drivers.tar.gz
   wget https://www.kernel.org/pub/linux/kernel/projects/rt/3.10/older/patch-3.10.25-rt23.patch.gz
   gunzip patch*
   mkdir kernel_sources
   cd kernel_sources
   git init
   git fetch git://github.com/raspberrypi/linux.git
   rpi-3.10.y:refs/remotes/origin/rpi-3.10.y
   git checkout rpi-3.10.y
   git reset --hard c43739885d512c92c0aa443b5895b96df5141da0
   git config --global user.name "you" && git config --global user.email
   "you@you.com"
   git am -3 /home/pi/rpi_wlf_3.10_beta/*
   cat /home/pi/patch-3.10.25-rt23.patch | patch -p1
   cp arch/arm/configs/rpi_wolfson_sound_pi_defconfig .config
   make menuconfig
   ==
   Kernel config -> CPU power management -> CPU frequency scaling ->
   Default governor -> performance
   Kernel config -> CPU power management -> CPU frequency scaling:
   Disable the non-performance governor modules, we don’t want them!
   Kernel config -> Kernel Features > Preemption Model -> Fully
   preemptible kernel (RT)
   ==
   make
   make modules
   sudo make modules_install
   sudo cp arch/arm/boot/Image /boot/kernel-rt.img
   /boot/config.txt
   disable_splash=1
   force_turbo=1
   kernel=kernel-rt.img
   /boot/cmdline.txt
   sdhci_bcm2708.enable_llm=0

3. install the alsa extras script: <a
   href="http://www.workinprogress.ca/wp-content/uploads/wolfson_alsa.zip">wolfson_alsa</a>

4. sudo su -c 'echo @audio - rtprio 99 >> /etc/security/limits.conf'
   sudo su -c 'echo @audio - memlock unlimited >> /etc/security/limits.conf'
   sudo su -c 'echo @audio - nice -10 >> /etc/security/limits.conf'
   reboot

5. install puredata from miller's site (http://msp.ucsd.edu/software.html)
   5.1) sudo chmod 4755 /home/pi/pd-0.46-1/bin/pd

6. disable the other soundcard sed -i 's/snd-bcm2835/#snd-bcm2835/g'
   /etc/modules

7. sudo apt-get install tightvncserver && vncserver :0 -geometry
   1920x1080 -depth 24
   add to svnc.sh chmod +x
   http://elinux.org/RPi_VNC_Server

8. start pd:
   sudo chrt -f -p 97 pgrep irq/27-arizona
   sudo renice -19 pgrep irq/27-arizona
   sudo pd-extended -rt -alsa -audiodev 1 -r 48000 -audiobuf 8 -channels
   2 -nogui -stderr -open mic.pd
   sudo renice -10 $(pidof pd-extended)
   sudo chrt -p 84 $(pidof pd-extended)

@EEight thaks for your answer!
I've got a couple of questions though...
In step 2, in the second set of instructions, you write the following:
"Kernel config -> CPU power management -> CPU frequency scaling ->
Default governor -> performance
Kernel config -> CPU power management -> CPU frequency scaling:
Disable the non-performance governor modules, we don’t want them!
Kernel config -> Kernel Features > Preemption Model -> Fully
preemptible kernel (RT)"

What do you mean by that exactly? Most of the other stuff is Unix commands, but this I don't really get.

Step 3, you say that I should install the extra scripts, that I can download from the url you provide. where do they go? according to the instructions that I mention in my first post, some of them are included in the .tar.gz the webpage says to download and expand, and they go to the home directory. Where should I install them?

Step 7, is this really necessary? I'm programming this kind of devices over SSH.

Thanks again

@alexandros said:

What do you mean by that exactly? Most of the other stuff is Unix commands, but this I don't really get.

It is only relevant if you want to compile a rt-kernel (when doing make menuconfig a console gui will appear so that you can tune your kernel). BTW, compiling a kernel on the rpi takes around 12 hours!

Step 3, you say that I should install the extra scripts, that I can download from the url you provide. where do they go?

I have created and found some extra scripts (remove DC for mics, equalizing...). They go anywhere and you call them like so ./Playback_to_Headset.sh

Step 7, is this really necessary? I'm programming this kind of devices over SSH.

It is optional.

Cheers~

Coming back to this thread after some time, cause I was rather busy and couldn't deal with this issue.
I went through setps 1 and 2, and things seemed ok. I shut down the Pi in order to continue with the rest another day, but now, when I power up the Pi, the router can't see it and I can't log in via SSH.
Maybe I did something wrong in the kernel configuration? The only thing I didn't grasp from this procedure is this: "Disable the non-performance governor modules, we don’t want them!"
I did disable some governor modules, but I'm not really sure which ones are the "non-performance" ones...is there a chance that I messed it up and the Pi won't boot? Should I do the whole procedure again?

@alexandros said:

is there a chance that I messed it up and the Pi won't boot?

Yes, it might also be my fault. My step-by-step guide is only tested by me and since I have good experience under my belt at compiling kernels it might be that I simply omit a step.

I would suggest to simply try to run the wolfson card without recompiling the kernel. I think there's a distribution from wolfson that works out of the box.

Cheers~

I'll give this one last try. before I do though (actually I'm at the process), concerning this part: "Kernel config -> CPU power management -> CPU frequency scaling: Disable the non-performance governor modules, we don’t want them!"

which ones from the following are they:
'performance' governor
'powersave' governor (sounds like...)
'userspace' governor for userspace frequency scaling
'ondemand' cpufreq policy governor
'conservative' cpufreq governor (also sounds like)

Cheers

@alexandros said:

• 'powersave' governor (sounds like...)
• 'userspace' governor for userspace frequency scaling
• 'ondemand' cpufreq policy governor
• 'conservative' cpufreq governor (also sounds like)

Good luck!