On Windows, the Bluetooth device can remain in a connected state if the controller just shut down. It won't return any errors, but it also won't generate any input reports in this state, so wait until we know for sure that the Bluetooth controller is sending data before letting the application know it's available.
Nintendo Switch controllers will automatically turn off Bluetooth when connected over USB, but this takes care of that a little more quickly.
PS4 and PS5 controllers will happily send reports over both Bluetooth and USB, so we'll prefer USB if connected and switch back to Bluetooth if USB is disconnected.
This prevents a number of issues where devices are enumerated but not actually able to be opened, like https://github.com/libsdl-org/SDL/issues/5781.
We currently leave the devices open, allowing us to more easily do controller feature detection, protocol negotiation, detect dropped Bluetooth connections, etc. with the expectation that the application is likely to open the controllers shortly.
We were returning the report size from HIDAPI_DriverPS5_RumbleJoystick() rather
than 0 upon success, causing SDL_JoystickRumble() (and callers) to think that
rumbling failed.
This didn't cause major problems until 1868c5b, when it started preventing
rumble state from being persisted in the joystick core, even though it was
successfully sent to the hardware.
This led to all sorts of strangeness, including broken rumble duration and
attempts to stop rumble being discarded.
Since accessing Bluetooth prompts the user for permission on both Android and iOS, and we only need it for Steam Controller support, we'll leave it off by default. You can enable it by setting the hint SDL_HINT_JOYSTICK_HIDAPI_STEAM to "1" before calling SDL_Init()
Fixes https://github.com/libsdl-org/SDL/issues/4952
This prevents conflicts with hidapi linked with applications, as well as allowing applications to make use of HIDAPI on Android and other platforms that might not normally have an implementation available.
Existing SDL applications may not know about the need to set a specific
hint to enable rumble on PS5 controllers, even though they may already
set the equivalent SDL_HINT_JOYSTICK_HIDAPI_PS4_RUMBLE hint for PS4
controller rumble support.
Rather than requiring those developers update their apps, let's use the
SDL_HINT_JOYSTICK_HIDAPI_PS4_RUMBLE value as an indication of the behavior
they are expected for all PlayStation controllers.
