Re: [Line6linux-devel] pod hd500x

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

On Mon, Jun 5, 2017 at 7:16 PM, Hans Peter Möller <hm...@gm...> wrote:
> The 4 EP (2 audio and 2 ctrl) match the ones from PODHD500_0 and PODHD500_1
> (do you know what are the ctrl or User for??) so it appears to be simple.

Not sure what you mean by "User", but the ctrl are used (well, can be
used) to transfer stuff like effects configuration.


>
> Now to test if this simple edit would be enough, I assume I have to
> uninstall the module from the kernel (line6usb comes with the kernel) and
> then compile and follow the instructions prior it was included in the
> kernel. Is that correct? If that's the case, what would be the best way to
> uninstall the module from teh kernel?

TBH, you should rather read some tutorial regarding this. This depends
on your distribution, google for "linux module rebuild" etc.


> I would also need to pin the kernel,
> so no kernel update with line6usb module mess with this right?
> thansk a lot.
>

That is the optimal solution. You can do such thing via dkms, for example.

Myself, I only use the driver occasionally, so everytime I need it,
I'll just basically do:

rmmod snd_usb_podhd
rmmod snd_usb_line6
cd $LINUX_SRC/sound/usb/line6/ # basically you only need the one
directory, not whole tree
make -C /lib/modules/`uname -r`/build M=$PWD
insmod snd-usb-line6.ko
insmod snd-usb-podhd.ko

(Of course, rmmod/insmod need to be executed as root).


-- 
Good luck,

A.

>
>
> On Sun, Jun 4, 2017 at 4:01 PM, Andrej Kruták <de...@an...> wrote:
>>
>> 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
>
>