diff mbox series

[v9,01/22] HID: pidff: Convert infinite length from Linux API to PID standard

Message ID 20250201113906.769162-2-tomasz.pakula.oficjalny@gmail.com
State New
Headers show
Series HID: Upgrade the generic pidff driver and add hid-universal-pidff | expand

Commit Message

Tomasz Pakuła Feb. 1, 2025, 11:38 a.m. UTC 
Software uses 0 as de-facto infinite lenght on Linux FF apis (SDL),
Linux doesn't actually define anythi as of now, 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@makarenk.ooo>
Signed-off-by: Makarenko Oleg <oleg@makarenk.ooo>
Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Reviewed-by: Michał Kopeć <michal@nozomi.space>
Reviewed-by: Paul Dino Jones <paul@spacefreak18.xyz>
Tested-by: Paul Dino Jones <paul@spacefreak18.xyz>
Tested-by: Cristóferson Bueno <cbueno81@gmail.com>
Tested-by: Pablo Cisneros <patchkez@protonmail.com>
---
 drivers/hid/usbhid/hid-pidff.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
diff mbox series

Patch

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;