Force Feedback Joystick support (MS Sidewinder FF2)

I want to figure out how much my force feedback joystick is actually supported in Ubuntu. Currently I have Ubuntu 20.04.05 LTS installed.

So far I can run

$ lsusb 
...
Bus 001 Device 006: ID 045e:001b Microsoft Corp. SideWinder Force Feedback 2 Joystick
...
$

and

$ jstest /dev/input/js0
Driver version is 2.1.0.
Joystick (Microsoft SideWinder Force Feedback 2 Joystick) has 6 axes (X, Y, Rz, Throttle, Hat0X, Hat0Y)
and 9 buttons (Trigger, ThumbBtn, ThumbBtn2, TopBtn, TopBtn2, PinkieBtn, BaseBtn, BaseBtn2, BtnDead).
Testing ... (interrupt to exit)
Axes:  0:  1852  1:     0  2:     0  3:     0  4:     0  5:     0 Buttons:  0:off  1:off  2:off  3:off  4:off  5:off  6:off  7:off  8:on

Both of them seem working fine, so the basic joystick functionality is good. Next, I want to check force feedback functionality. I read https://docs.kernel.org/input/ff.html and thus tried

$ fftest /dev/input/js0
Force feedback test program.
HOLD FIRMLY YOUR WHEEL OR JOYSTICK TO PREVENT DAMAGES

Device /dev/input/js0 opened
Features:
Ioctl absolute axes features query: Invalid argument

but then the documentation talks about some eventXX device file. Unfortunately it does not mention which one to use. So I added my user to the input group and tried

$ fftest /dev/input/event0
Force feedback test program.
HOLD FIRMLY YOUR WHEEL OR JOYSTICK TO PREVENT DAMAGES

Device /dev/input/event0 opened
Features:
  * Absolute axes: 
    [00 00 00 00 00 00 00 00 ]
  * Relative axes: 
    [00 00 ]
  * Force feedback effects types: 
    Force feedback periodic effects: 
    [00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ]
  * Number of simultaneous effects: 0

Uploading effect #0 (Periodic sinusoidal) ... Error:: Function not implemented
Uploading effect #1 (Constant) ... Error: Function not implemented
Uploading effect #2 (Spring) ... Error: Function not implemented
Uploading effect #3 (Damper) ... Error: Function not implemented
Uploading effect #4 (Strong rumble, with heavy motor) ... Error: Function not implemented
Uploading effect #5 (Weak rumble, with light motor) ... Error: Function not implemented
Enter effect number, -1 to exit

Regardless of what number I enter, my joystick behaves the same: it uses force to just center the stick. Probably just because the functions are not implemented. But then the same happens, regardless of which file I specify:

/dev/input/event0
/dev/input/event1
/dev/input/event...

Is it the case that my joystick is not supported? According to https://docs.kernel.org/input/joydev/joystick.html#microsoft-sidewinder-joysticks the Overdrive Protocol seems there.

What else could be missing?

I may have come across the real issue. The kernel documentation https://docs.kernel.org/input/joydev/joystick.html#microsoft-sidewinder-joysticks lists these supported devices:

• Microsoft SideWinder 3D Pro
• Microsoft SideWinder Force Feedback Pro
• Microsoft SideWinder Force Feedback Wheel
• Microsoft SideWinder FreeStyle Pro
• Microsoft SideWinder GamePad (up to four, chained)
• Microsoft SideWinder Precision Pro
• Microsoft SideWinder Precision Pro USB

Notice something? The Force Feedback 2 joystick is not listed. So I downloaded the kernel source code from https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.1.6.tar.xz and checked the file linux-6.1.6/drivers/input/joystick/sidewinder.c. It contains

static char *sw_name[] = {  "3D Pro", "GamePad", "Precision Pro", "Force Feedback Pro", "FreeStyle Pro",
                "Force Feedback Wheel" };

which matches the above list but again omits the Force Feedback 2 joystick. Seems to be a forgotten artifact.