mirror of https://github.com/torvalds/linux.git
87 lines
2.5 KiB
C
87 lines
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/* Copyright (c) 2025 Curran Muhlberger
|
|
*/
|
|
|
|
#include "vmlinux.h"
|
|
#include "hid_bpf.h"
|
|
#include "hid_bpf_helpers.h"
|
|
#include <bpf/bpf_tracing.h>
|
|
|
|
#define VID_LOGITECH 0x046D
|
|
#define PID_SPACENAVIGATOR 0xC626
|
|
|
|
HID_BPF_CONFIG(
|
|
HID_DEVICE(BUS_USB, HID_GROUP_ANY, VID_LOGITECH, PID_SPACENAVIGATOR)
|
|
);
|
|
|
|
/*
|
|
* The 3Dconnexion SpaceNavigator 3D Mouse is a multi-axis controller with 6
|
|
* axes (grouped as X,Y,Z and Rx,Ry,Rz). Axis data is absolute, but the report
|
|
* descriptor erroneously declares it to be relative. We fix the report
|
|
* descriptor to mark both axis collections as absolute.
|
|
*
|
|
* The kernel attempted to fix this in commit 24985cf68612 (HID: support
|
|
* Logitech/3DConnexion SpaceTraveler and SpaceNavigator), but the descriptor
|
|
* data offsets are incorrect for at least some SpaceNavigator units.
|
|
*/
|
|
|
|
SEC(HID_BPF_RDESC_FIXUP)
|
|
int BPF_PROG(hid_fix_rdesc, struct hid_bpf_ctx *hctx)
|
|
{
|
|
__u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 4096 /* size */);
|
|
|
|
if (!data)
|
|
return 0; /* EPERM check */
|
|
|
|
/* Offset of Input item in X,Y,Z and Rx,Ry,Rz collections for all known
|
|
* firmware variants.
|
|
* - 2009 model: X,Y,Z @ 32-33, Rx,Ry,Rz @ 49-50 (fixup originally
|
|
* applied in kernel)
|
|
* - 2016 model (size==228): X,Y,Z @ 36-37, Rx,Ry,Rz @ 53-54
|
|
*
|
|
* The descriptor size of the 2009 model is not known, and there is evidence
|
|
* for at least two other variants (with sizes 202 & 217) besides the 2016
|
|
* model, so we try all known offsets regardless of descriptor size.
|
|
*/
|
|
const u8 offsets[] = {32, 36, 49, 53};
|
|
|
|
for (size_t idx = 0; idx < ARRAY_SIZE(offsets); idx++) {
|
|
u8 offset = offsets[idx];
|
|
|
|
/* if Input (Data,Var,Rel) , make it Input (Data,Var,Abs) */
|
|
if (data[offset] == 0x81 && data[offset + 1] == 0x06)
|
|
data[offset + 1] = 0x02;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
HID_BPF_OPS(logitech_spacenavigator) = {
|
|
.hid_rdesc_fixup = (void *)hid_fix_rdesc,
|
|
};
|
|
|
|
SEC("syscall")
|
|
int probe(struct hid_bpf_probe_args *ctx)
|
|
{
|
|
/* Ensure report descriptor size matches one of the known variants. */
|
|
if (ctx->rdesc_size != 202 &&
|
|
ctx->rdesc_size != 217 &&
|
|
ctx->rdesc_size != 228) {
|
|
ctx->retval = -EINVAL;
|
|
return 0;
|
|
}
|
|
|
|
/* Check whether the kernel has already applied the fix. */
|
|
if ((ctx->rdesc[32] == 0x81 && ctx->rdesc[33] == 0x02 &&
|
|
ctx->rdesc[49] == 0x81 && ctx->rdesc[50] == 0x02) ||
|
|
(ctx->rdesc[36] == 0x81 && ctx->rdesc[37] == 0x02 &&
|
|
ctx->rdesc[53] == 0x81 && ctx->rdesc[54] == 0x02))
|
|
ctx->retval = -EINVAL;
|
|
else
|
|
ctx->retval = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
char _license[] SEC("license") = "GPL";
|