Linux defines 0 length as infinite in its force feedback API while USB PID defines NULL (0xffff). Most PID devices do not expect a 0-length effect and can't interpret it as infinite. This change fixes Force Feedback for most PID compliant devices. As most games depend on updating the values of already playing infinite effects, this is crucial to ensure they will actually work. Previously, users had to rely on third-party software to do this conversion and make their PID devices usable. Co-developed-by: Makarenko Oleg <oleg@xxxxxxxxxxxx> Signed-off-by: Makarenko Oleg <oleg@xxxxxxxxxxxx> Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@xxxxxxxxx> --- drivers/hid/usbhid/hid-pidff.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c index 3b4ee21cd811..5fe4422bb5ba 100644 --- a/drivers/hid/usbhid/hid-pidff.c +++ b/drivers/hid/usbhid/hid-pidff.c @@ -21,6 +21,7 @@ #include "usbhid.h" #define PID_EFFECTS_MAX 64 +#define PID_INFINITE 0xffff /* Report usage table used to put reports into an array */ @@ -301,7 +302,12 @@ static void pidff_set_effect_report(struct pidff_device *pidff, pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0]; pidff->set_effect_type->value[0] = pidff->create_new_effect_type->value[0]; - pidff->set_effect[PID_DURATION].value[0] = effect->replay.length; + + /* Convert infinite length from Linux API (0) + to PID standard (NULL) if needed */ + pidff->set_effect[PID_DURATION].value[0] = + effect->replay.length == 0 ? PID_INFINITE : effect->replay.length; + pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button; pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] = effect->trigger.interval; -- 2.48.1