some SteelSeries additions & fixes for Windows

[stevenjamescox]

• Added 030000003810000060b3000000007801 - SteelSeries Nimbus for Windows - This controller requires MFI Gamepad Feeder (or a similar driver if it exists) for it to have any function in Windows.

• Added 030000000d0000000000000000000000 - SteelSeries Nimbus+ for Windows - R2 & L2 are missing because they're not recognized by SDL2 Gamepad Tool. They aren't recognized in RetroArch or any other application I tried. But they do appear to work in Windows Control Panel's "HID-compliant game controller" Properties interface.

• No change to 03000000110100003114000000000000 - SteelSeries Stratus Duo via Bluetooth for Windows - The guide button is missing but it's not recognized by SDL Gamepad Tool. It makes sense that this button doesn't function well in Windows as this controller's Bluetooth mode was specifically designed for Android.

• Added missing guide button to 03000000381000003014000000000000- SteelSeries Stratus Duo via 2.4GHz USB receiver for Windows - The guide button will bring up the Xbox Game Bar by default, but this can be easily turned off in Settings by unchecking a box in the section for Xbox Game Bar. It appears that this box must be unchecked for the SDL2 Gamepad Tool to be able to record the guide button input.

• Added missing guide button for 03000000381000003114000000000000- SteelSeries Stratus Duo via USB cable for Windows - Same situation as the previous one.

• Added 03000000381000003014000000007801 - SteelSeries Stratus Duo via 2.4GHz USB receiver for Windows - Maybe this a legitimate alternate GUID, but I'm thinking it's just a duplicate of 03000000381000003014000000000000 because I'm not seeing 7801 at the end of any current Windows GUIDs. This is, however, the number my controller brings up in SDL2 Gamepad Tool. Could this have anything to do with the tool being slightly outdated and/or using a less-than-current version of SDL?

• Added 03000000381000003114000000007801 - SteelSeries Stratus Duo via USB cable for Windows - Same situation as previous one, this is probably an erroneous duplicate.

[offalynne]

The 7801 suffix indicates XInput, which means a device should not need mapping as SDL handles it already: #478 (comment)

030000000d0000000000000000000000: This GUID is rather the opposite of Unique and doesn't inspire confidence, so I think it's best to omit this as well. Less of a problem for other mapping projects like RetroArch that can match on name alone.

All good as for the rest, thank you for the helpful detail!

[stevenjamescox]

Thank you, as always, for your patience with my being a novice!

I keep seeing devices' hardware IDs split in half and reassembled back-to-back near the middle of these GUIDs, is that standard? I've been trying to find some sort of reference material that fully explains how to break down SDL GUIDs but have come up empty.

The Nimbus+ is truly an odd one. Vendor ID 0x000d, Product ID 0x0000. I am not familiar with the particulars of HID-compliance, device-identification compliance, etc., but it seems like a product ID of zero has to be a no-no. It's like they thought, "This'll just be used on iOS/tvOS, so we only have to care about its adherence to MFi specs," OR could it be that it doesn't even have a product ID and so systems just show it as zero?

[offalynne]

GUID format is

XXXX 0000 XXXX 0000 XXXX 0000 XXXX XXXX
|    |    |    |    |    |    |    |
|    |    |    |    |    |    |    Flag
|    |    |    |    |    |    Version
|    |    |    |    |    Padding
|    |    |    |    Product
|    |    |    Padding
|    |    Vendor
|    Padding
DeviceBusType

Where Flag is one of several internal values (we intend to omit devices with these from the db): https://github.com/libsdl-org/SDL/blob/d58d637ac6bd84a3fb30ecbfc50e8454fac9d9fa/src/joystick/SDL_joystick.c#L2190-L2217

split in half and reassembled back-to-back

This is just an endianness difference from how vendor and product are usually presented.

reference material

Not much available, pretty much have to read the C source.

Very few of these gamepad devices (including all of first-party console manufacture) are properly HID-complaint, it does seem like most vendors use the spec to the bare minimum necessary to get things working and no further.

could it be that it doesn't even have a product ID and so systems just show it as zero

Could well be the case, I have the Nimbus+ on hand as well but have never looked thoroughly into it's device descriptors.