xref: /linux/scripts/coccinelle/hid/ff_race.cocci (revision a93f3bf4e1d60777b1659b812c9e818cfc53b449)
1/// Detect HID drivers that initialize force-feedback after hid_hw_start()
2/// when HID_CONNECT_HIDINPUT is used. This is a lifecycle violation as
3/// the input device is already registered.
4//
5// Confidence: High
6// Copyright: (C) 2026 Gemini. GPLv2.
7
8virtual report
9
10@r@
11identifier probe_fn;
12expression hdev, flags;
13position p1, p2;
14@@
15
16probe_fn(struct hid_device *hdev, ...) {
17  <...
18  hid_hw_start@p1(hdev, flags)
19  ...
20  \(input_ff_create\|input_ff_create_memless\)@p2(...)
21  ...>
22}
23
24@script:python depends on report@
25p1 << r.p1;
26p2 << r.p2;
27flags << r.flags;
28@@
29
30# Check if flags include HID_CONNECT_HIDINPUT (0x01) or HID_CONNECT_DEFAULT (0x0f)
31# Note: HID_CONNECT_DEFAULT is 0x0f, HID_CONNECT_HIDINPUT is 0x01
32if "HID_CONNECT_HIDINPUT" in flags or "HID_CONNECT_DEFAULT" in flags:
33    msg = "WARNING: force-feedback initialized after hid_hw_start() with HID_CONNECT_HIDINPUT. Input device is already registered at this point. Use .input_configured() instead."
34    coccilib.report.print_report(p2[0], msg)
35