Thread (22 messages) 22 messages, 2 authors, 27d ago

Re: [PATCH v5 10/12] Input: Add ABS_CLUTCH, HANDBRAKE, and SHIFTER

From: sashiko-bot@kernel.org
Date: 2026-09-02 01:23:27

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] The hid-universal-pidff driver fails to adjust fuzz and deadzone for the newly added racing axes (ABS_CLUTCH, ABS_HANDBRAKE, ABS_SHIFTER).
--

commit 6be790038ce1202a4794a1e9066e937b7c0b308a
Author: Vicki Pfau [off-list ref]

Input: Add ABS_CLUTCH, HANDBRAKE, and SHIFTER

This commit adds new absolute axes for racing game controllers.

[ ... ]
quoted hunk ↗ jump to hunk
diff --git a/include/uapi/linux/input-event-codes.h b/include/uapi/linux/input-event-codes.h
index 3528168f7c6d7..5c881ed441771 100644
--- a/include/uapi/linux/input-event-codes.h
+++ b/include/uapi/linux/input-event-codes.h
@@ -879,6 +879,9 @@
 #define ABS_WHEEL		0x08
 #define ABS_GAS			0x09
 #define ABS_BRAKE		0x0a
+#define ABS_CLUTCH		0x0b
+#define ABS_HANDBRAKE		0x0c
+#define ABS_SHIFTER		0x0d
[Severity: Medium]
Will this cause an issue with fuzz and deadzone adjustment for the newly
added racing axes?

Looking at drivers/hid/hid-universal-pidff.c in
universal_pidff_input_configured(), there is a loop that controls the fuzz
and deadzone configuration for racing controllers:

	/* Decrease fuzz and deadzone on available axes */
	for (axis = ABS_X; axis <= ABS_BRAKE; axis++) {
		if (!test_bit(axis, input->absbit))
			continue;

This loop stops at ABS_BRAKE, skipping the newly appended ABS_CLUTCH,
ABS_HANDBRAKE, and ABS_SHIFTER axes.

High-resolution inputs for these newly added axes (like a clutch pedal or
analog handbrake) will retain the HID input core's default large fuzz or
deadzone values. This could lead to "steppy" input response and dropped
small movements.

Does the loop in universal_pidff_input_configured() need to be updated to
include these new axes?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260902010237.865772-1-vi@endrift.com?part=10
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