Re: [Line6linux-devel] pod hd500x

[Andrej K. <de...@an...>]

Hi there,

On Thu, Jun 1, 2017 at 1:19 AM, Hans Peter Möller <hm...@gm...> wrote:
>    I want to help to inlude the pod hd500x in the driver. I've never done
> some driver programming but I have done a lot of coding myself, from ASM in
> a PIC to php, java, javascript, vb, c, c#, etc... If you can give me some
> info to read and study it would be great to start.
>
> Do you use wireshark to do the reverse ingeneering stuff? I'f done some
> basic stuff with it.
>
> Hope to hear from you soon.
>

There's not a lot of traffic here anymore, sadly - so you are veru
much on your own.


Anyhow, depends on what you want to do. If it's only the audio
support, with a bit of luck it will be as simple as editing
sound/usb/line6/podhd.c. Add LINE6_PODHD500X similarly like
PODHD500_0. Check the endpoints (esp. the audio ones) match what you
see in lsusb. If POD HD500X has more than 2+2 audio channels, get
inspired at POD X3.

If you would like to edit the presets etc., you'd have to reverse
engineer the binary protocol. Basically install some USB sniffer (for
me http://www.usblyzer.com/ worked fine), dump the binary stuff (from
bulk endpoints) and have fun. If you cannot get any audio, you may
need some control interface initialization - again check POD X3 or
pod.c.

I have written down steps I had to do to get POD X3 working - maybe
you'll find them useful. http://andree.sk/2016/11/podx3 (there's also
link to some WIP python binary protocol decoder) ... Perhaps the
binary protocol is similar, in such case we could share some efforts.
POD X3's is actually quite simple - but I never got the time to
implement a GUI for it. Maybe if it turned out it'd be useful also for
other PODs, it would be more temptin ;-)

-- 
Greetings & good luck,

Andrej