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Date: Tue, 21 May 2024 22:07:19 +0000
From: Paul Dino Jones <paul@spacefreak18.xyz>
To: anssi.hannula@gmail.com, jikos@kernel.org
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH RESEND] Interpret 0 length ff effects as infinite (0xffff)
 length effects
Message-ID: <20240521220719.niwhskc473he5r5o@zitz>
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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@spacefreak18.xyz>
---
 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