Logitech HID confusion

[Clément VUCHENER]

Hi, DJ is a protocol for splitting the events from multiple devices
that use the same unifying receiver. There is some documentation here
: https://drive.google.com/drive/folders/0BxbRzx7vEV7eWmgwazJ3NUFfQ28.

2018-02-06 23:35 GMT+01:00 Christoph Böhmwalder <christoph at boehmwalder.at>:
> Kind of off topic for this list, but maybe somebody on here knows
> something about this.
>
> Looking through some the HID drivers, I've noticed that the Logitech
> Unifying Receiver HID driver is actually split up into
> hid-logitech-dj.c and hid-logitech-hidpp.c.
>
> Now I've heard about HID++, and from my research it seems that it's
> Logitech's custom HID protocol which it uses to communicate through the
> Unifying Receiver.  What's odd to me is the "dj" though.  Looking
> through the HID documentation really gave no clues.
>
> Skimming through the source code it seems like there's some sort of "DJ
> Mode" for certain Logitech devices?  I also found an old patch [1] that
> talks about "DJ devices [...] (T400, M325,...)".  Googling these product
> names reveals that there seems to be nothing special about them.
>
> I'm really confused, as there seems to be no public documentation on
> what this DJ mode actually is or does (or maybe I'm just overlooking
> something glaringly obvious).  I'd be grateful if someone took the time
> to point me in the right direction here.
>
> Thanks!
>
> --
> Regards,
> Christoph
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies