mirror of
https://github.com/libretro/RetroArch.git
synced 2026-11-12 18:45:33 -10:00
LibretroAdmin
45dc0a99c3
libShake was used by one driver, sdl_dingux, for its vibration motor, and linked on webOS for nothing. What it did there is a few evdev calls: find the node that plays a periodic sine, upload a sine per motor, play and stop it, set the gain. input/common/linux_ff.h does those with no allocation (libShake scanned /dev/input with scandir and malloc'd a node per entry) and none of its bugs (an open that failed was taken as success). The uploads and plays now go out from the shared output writer, as udev's and XInput's rumble do, so a motor's driver never holds the frame; the frontend's thread notes the strengths, both in one word, and returns. A core asking the same strength each frame costs no call at all. On MIPS (-O2, mips32) that path is 15 to 19 instructions with no stack frame, where it was about 32 with a frame and four spills. Every SDL Dingux target gets the motor now, not only the three that built libShake; one without a motor finds none and has no rumble, as before. The output writer makes no syscall for a wake while one is still on its way, which every driver on it gains from. xinput_rumble_test says a call did not wait by the write not being done yet, not by a time a loaded runner can overrun. samples/input/dingux_rumble runs the real driver against a stand-in /dev/input and SDL, with threads and without.