Re: [PATCH] Input: xpad: Spelling fixes for "Xbox", improve and proofread the listed xpad device names

[Swyter <swyterzone@gmail.com>]

On 31/07/2020 8:33, Cameron Gutman wrote:
>> While doing my research I also noticed that the 1532:0037 VID/PID seems to
>> be used by the DeathAdder 2013, so that Razer Sabertooth instance looks
>> wrong and very suspect to me, I created a separate patch for that.
> 
> The above sentence probably doesn't belong in the commit message.
> 

Fair enough, I should probably turn that into "reviewer" notes.
I think I mentioned it because I didn't update that bad entry.

Thinking it would be deleted soon. But good point.


> The docs and comment changes look fine to me.

Great, I was a bit wary about this.


> I'm somewhat concerned about the possibility of breaking userspace by changing
> names. Some programs' gamepad mappings may be dependent on matching the device
> names, rather than the VID+PID.
> 
> For example, Android did not expose the VID and PID for input devices until
> Android 4.4. The device name was the only available attribute for matching
> gamepads from Android 2.3 to 4.3. While these ancient Android version will
> almost certainly never run a kernel with this patch, I worry about the
> possibility of apps that haven't moved to VID+PID matching (and not just for
> Android; I don't know if other libraries or frameworks have/had similar
> limitations).
> 
> Perhaps my concerns are overblown, but If we aren't worried about changing
> names, I'd really prefer to just drop the hardcoded names entirely and use the
> manufacturer and product strings provided in the USB string descriptors. The
> device list would turn into a quirk list where only device entries with a
> special mapping flag like MAP_DPAD_TO_BUTTONS or MAP_TRIGGERS_TO_BUTTONS would
> remain, and the device name strings would just become comments on each quirk
> entry.
> 
> Thoughts?
> 
> 
> 
> 
> Regards,
> Cameron
> 

I don't doubt that changing some names will break some basic rule matching.

But given that the kernel nomenclature is so inconsistent, I think anyone searching
for "X-Box" and five other variants will also have to search for the actual "Xbox",
or at least I hope so. Keep in mind that I have tried to make each overhauled entry
*more* detailed when possible. So now each model has extra information (mainly
manufacturer and button-layout type) instead only some vague/informal model name.

SDL2 and Unity abstract these things a bit. I actually implement similar strings
checks in my own game/engine as fallback and it's exactly what I ended up doing.

I generally don't trust device strings, they'll be less detailed than these.
A good bunch of those are unlicensed, so they'll be wrong or missing.

Let me know what you think.