New reworked driver for Wolfson/Cirrus Logic audio card

Hias,

A huge thank-you for all the work you've put into supporting the Cirrus Audio card.  Until now I've been using your kernel packages, and have just got round to trying the latest official 4.9 kernel which is also working very nicely.  It's a real shame that the Cirrus card has (or appears to have) gone out of production just when the software support became so good.  The older Wolfson cards are still available, so perhaps I'll get a couple and try modifying them to fit a 40-pin header.  Anyway, thanks again for everything you've done.  I really do appreciate it.

Tim

The Cirrus Card does seem to be out of stock everywhere - what a shame.  I just started working on an alternative ultrasound sensistive microphone, since the electret type I was using has been out of production for years and is now virtually impossible to get hold of.

What other options are there for recording audio at 192kHz with the Raspberry Pi?

Hias and John,

I got my "Frankenson" sound card working with a Pi2 .

I didn't de-solder the pogo pins.  I found a cover that fits over them nicely - made from a UK 3-pin mains plug protector that all new electrical devices come with.  I cut the end off the Earth pin end of the protector.  It fits neatly onto the pogo pins.  Once the Wolfson card is attached to the Pi, the cover is held nicely in place, and stops them shorting on anything on the Pi.

Here's the pogo cover made from a plug protector:

Thanks for your help with this neat hack.

Hystrix

Bravo, I like it.  One of the positive british traits that, improvisation.

I knew UK plugs would prove better one day .... It has only taken 60 years  ..... Ironically I cut the last one off my appliances only this week.

More seriously, note that there is a wee bit of strain introduced by the pin protector, perhaps raise the Wolfson card a millimetre to compensate.

I have just made the mark 1 piggy back board, so if I can get the single sided version to work, expect photos of that too.  It's good to see an active community

Ha!  I knew someone would mention the strain caused by the pogo pin protector.    This was an early photo - I actually trimmed off some more of the plastic on the left-hand side.  You can see the black header is catching on it in the photo - it's much better now.

My only concern is whether the springs in the pogo pins will eventually start to push the audio card off the header.  Time will tell.  I may even file off some of the plastic from the bottom of the pin protector, so the springs aren't compressed as much.

I look foward to the photos of the piggy-back board.

I got my "Frankenson" sound card working with a Pi2 .

 

I didn't de-solder the pogo pins. I found a cover that fits over them nicely - made from a UK 3-pin mains plug protector that all new electrical devices come with. I cut the end off the Earth pin end of the protector. It fits neatly onto the pogo pins. Once the Wolfson card is attached to the Pi, the cover is held nicely in place, and stops them shorting on anything on the Pi.

That's looking really nice, well done! And I think the cap over the pogo pins is a rather clever idea!

so long,

Hias

All,

I promised an update on the piggy back card approach. Apologies for the delay, real world demands ...

First a photo

Herewith my observations

1)  Making the pcb at home is a pain for the following reasons.

1.     Drilling the board exactly (for the headers) is difficult.
2.      I can do only single sided boards and this approach demands "creativity" when installing the 26 pin header for the Wolfson. Plated through holes would be better/easier/stronger
3.     (and worst) the pads to receive the pogo connectors must be gold plated (So whilst my card works at the moment, I await the effects of O2)

So the board needs to be made professionally to be a good long term option  .... and that will mean 10 of them!

2) The Wolfson is well clear of the main board.  This is good for ventilation and for access to the ribbon cable connectors if you need them. It is bad in terms of mechanical support of the card.

3) It does offer a zero mod way of connecting the Wolfson to a pi 2/3

Overall I shall probably "sacrifice" a pi 3 and cut pin 12 off the Pi header and connect Wolfson direct to pi 3, ie not bother with a piggy back board .  It is a minor mod and will have probably no impact on any future project  ... and a pi is easier to source than these sound cards!  So, with the exception of not removing R39, I will probably follow the same route as others on the forum.   But if your project needs easy access to those ribbon sockets, the piggy back route is worth considering.

Good job I am a Brit (expat) and still have one of those mains plug shrouds!

Nice PCB!  If you are taking orders for a professionally made piggy-back board, put me down for one .

By the way, I emailed Cirrus Logic earlier in the week about the status of the Audio Card, because I assume that once the Wolfson Card stocks are depleted, we have no means of recording audio with a Pi at 192 kHz.

Hystrix,

thank you for those kind words.  No promises about the board, but Matthias rightly pointed out that the piggy back board should support the Wolfson card.  So do you have any feelings about how to use the extra board space? (Around 12cm2).  I really need a good digitally controlled attenuator, much better to run the Wolfson to full 24 bit accuracy,  but that is an output too high for most power amps..  I have a really nice design (not mine), based on relays .  Yes the clicky things! But it needs around 50cm2.

Yes.  I have a stock of 3 Wolfson cards at the moment, but I am thinking of getting a couple more. Perhaps we could persuade Cirrus to release the design into the public domain  .... and then we would have to whip enough enthusiasm  for a group build!  But I suspect that Cirrus would like to lose the design in favour of their own devices   ..... though I do note the existence of the wm8281 (datasheet Jan 2017),  which looks very much like an update of the WM5102 .... it might even be upward driver compatible. I note too that some linux kernels have been adapted

Matthias,

Really sorry to bother you, but having got my piggy back +pi 3 working, I played with the kernel. Fatal mistake.  I had been running Runeaudio + your(?) 4.4.14 kernel, but I have messed up.  I could spend days finding the problem (and 5 minutes fixing it), but perhaps it is time to leave the past behind. What kernel would you recommend to run headless MPD, with linux shell available over SSH and the ability to run brutefir? It sounds like I dont need Jessie (which you kindly support) nor the librelec kernel (which you kindly support).

Many thanks in advance

Hi John!

What kernel would you recommend to run headless MPD, with linux shell available over SSH and the ability to run brutefir? It sounds like I dont need Jessie (which you kindly support) nor the librelec kernel (which you kindly support).

I'd recommend using Raspbian Lite (Jessie), this is what I'm using for my (mostly headless) test setups as well. The Lite version comes with a minimal set of packages preinstalled, no desktop environment and unnecessary cruft for headless setups, and you can easily install the packages you want. mpd and brutefir are all available from the Raspbian repo, "sudo apt-get install mpd brutefir" and you can get going Ah, well, and "sudo rpi-update" for the 4.9 kernel with cirrus drivers plus downloading the mixer scripts, of course

so long,

Hias

Matthias,

As always, thanks for the rapid reply.  It all went smoothly, though not as quickly as I would like.  Below I have listed the steps I took in painstaking detail ....  Obviously this is stuff you already know!  But if somebody else wants to do the same thing, it saves you from having to reply.  Your instructions at RPi Linux driver for Wolfson / Cirrus Logic Audio Card are concise and 100% correct.  Here I just spell it out.

1) Download jessie lite and unzip it from the base repository

2) In a terminal on a linux machine with a blank memory card inserted (at device $)

        sudo dd bs=4M if=2017-03-02-raspbian-jessie-lite.img of=/dev/sd$

3) SSH is enabled in jessie by creating a file with name "ssh" in the boot partition

4) Install card and boot pi (with wired ethernet)

5) SSH to device  ssh $.$.$.$ -l pi (password=raspberry), thence

    sudo apt-get install rpi-update

    sudo rpi-update (y at prompt.  We do this to get the 4.9 kernel to get the driver for the Wolfson)

    sudo raspi-config (to enable i2c and spi, follow the menus)

    sudo reboot

6) SSH to device (again)

    uname -a (just to check at kernel 4.9)

    sudo apt-get install mpd brutefir (to install my tools for later)

(this failed, so)

    sudo apt-get update

    sudo apt-get install mpd brutefir (to install my tools for later)

(locale warnings from perl, but unpacks a lot more, esp stuff for brutefir like fft)

    sudo apt-get install mpc (useful add on to mpd)

    sudo apt-get install i2c-tools (to check device presence.  8804 on card shows at 3b using  sudo i2cdetect -y 1)

    sudo apt-get install vim to get vim editor (easier to edit through SSH than playing the permissions game through ftp)

(you could wrap all those gets up into a single line, skip the reboot etc, this is just my log!)

   sudo vim /boot/config.txt (uncomment #dtparam=i2s=on and add the line "dtoverlay=rpi-cirrus-wm5102")

    sudo vim /etc/modprobe.d/cirrus.conf (to create new file, with content "softdep arizona-spi pre: arizona-ldo1")

    sudo reboot

SSH to device

At this point aplay -l shows the (piggy backed) Wolfson card and alsamixer allows you to play with it

(Apologies to all, I must learn the correct protocol for doing this on the board)

Matthias,

As always, thanks for the rapid reply.  It all went smoothly, though not as quickly as I would like.  Below I have listed the steps I took in painstaking detail ....  Obviously this is stuff you already know!  But if somebody else wants to do the same thing, it saves you from having to reply.  Your instructions at RPi Linux driver for Wolfson / Cirrus Logic Audio Card are concise and 100% correct.  Here I just spell it out.

1) Download jessie lite and unzip it from the base repository

2) In a terminal on a linux machine with a blank memory card inserted (at device $)

        sudo dd bs=4M if=2017-03-02-raspbian-jessie-lite.img of=/dev/sd$

3) SSH is enabled in jessie by creating a file with name "ssh" in the boot partition

4) Install card and boot pi (with wired ethernet)

5) SSH to device  ssh $.$.$.$ -l pi (password=raspberry), thence

    sudo apt-get install rpi-update

    sudo rpi-update (y at prompt.  We do this to get the 4.9 kernel to get the driver for the Wolfson)

    sudo raspi-config (to enable i2c and spi, follow the menus)

    sudo reboot

6) SSH to device (again)

    uname -a (just to check at kernel 4.9)

    sudo apt-get install mpd brutefir (to install my tools for later)

(this failed, so)

    sudo apt-get update

    sudo apt-get install mpd brutefir (to install my tools for later)

(locale warnings from perl, but unpacks a lot more, esp stuff for brutefir like fft)

    sudo apt-get install mpc (useful add on to mpd)

    sudo apt-get install i2c-tools (to check device presence.  8804 on card shows at 3b using  sudo i2cdetect -y 1)

    sudo apt-get install vim to get vim editor (easier to edit through SSH than playing the permissions game through ftp)

(you could wrap all those gets up into a single line, skip the reboot etc, this is just my log!)

   sudo vim /boot/config.txt (uncomment #dtparam=i2s=on and add the line "dtoverlay=rpi-cirrus-wm5102")

    sudo vim /etc/modprobe.d/cirrus.conf (to create new file, with content "softdep arizona-spi pre: arizona-ldo1")

    sudo reboot

SSH to device

At this point aplay -l shows the (piggy backed) Wolfson card and alsamixer allows you to play with it

(Apologies to all, I must learn the correct protocol for doing this on the board)

Postscript,

The rest of getting the new system working went very smoothly, a bog standard MPD configuration and moving the system to run from HD (I don't like writing to SD ad infinitum) .  The only hiccup came when I imported my alsactl state file (alsactl allows you to store and restore complete configurations for the sound card, very useful when playing with something as complex as this sound card).  Matthias has indicated in an earlier post that the driver had changed and so my import failed    ...... my own silly fault .......

alsactl: set_control:1325: failed to obtain info for control #36 (No such file or directory)        (ditto 37,38,39)

alsactl: set_control:1325: failed to obtain info for control #162 (No such file or directory)

alsactl: set_control:1325: failed to obtain info for control #298 (No such file or directory)       (ditto 299,300,301)

alsactl: set_control:1325: failed to obtain info for control #461 (No such file or directory)       (ditto 462,463,464)

The first group are the EQn filter equalisation parameters, which I use as a partial room correction filters....... in fact a large number of other controls have changed numbering too, so I do not suggest this path for migrating parameters

So now a few tweaks and I am done!

(Matthias,  I remember you mentioning the EQ parameters changing from 42 to 40 bytes, so no need to reply, unless you want to.  It is only when you look at the state file that you realise how enormous the driver is.  Yet again, many thanks)