[PATCH RESEND] Interpret 0 length ff effects as infinite (0xffff) length effects

From: Paul Dino Jones
Date: Tue May 21 2024 - 18:08:42 EST


Greetings,

More and more vendors are entering the force feedback wheel space, and
many are supported well by this driver. Unfortunately a lot of new users
are hitting this issue.

It would be nice to have this merged.

I think we all agree a 0 length effect makes no sense, and this change
wouldn't break anything that sends 0xffff.

Signed-off-by: Paul Dino Jones <paul@xxxxxxxxxxxxxxxx>
---
drivers/hid/usbhid/hid-pidff.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index 3b4ee21cd811..70653451c860 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -301,7 +301,7 @@ 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;
+ pidff->set_effect[PID_DURATION].value[0] = effect->replay.length == 0 ? 0xffff : 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;
--
2.35.1