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1// SPDX-License-Identifier: GPL-2.0-only2/* Copyright (c) 2023 Benjamin Tissoires3 */4 5#include "vmlinux.h"6#include "hid_bpf.h"7#include "hid_bpf_helpers.h"8#include <bpf/bpf_tracing.h>9 10#define VID_IOGEAR 0x258A /* VID is shared with SinoWealth and Glorious and prob others */11#define PID_MOMENTUM 0x002712 13HID_BPF_CONFIG(14 HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, VID_IOGEAR, PID_MOMENTUM)15);16 17/*18 * The IOGear Kaliber Gaming MMOmentum Pro mouse has multiple buttons (12)19 * but only 5 are accessible out of the box because the report descriptor20 * marks the other buttons as constants.21 * We just fix the report descriptor to enable those missing 7 buttons.22 */23 24SEC(HID_BPF_RDESC_FIXUP)25int BPF_PROG(hid_fix_rdesc, struct hid_bpf_ctx *hctx)26{27 const u8 offsets[] = {84, 112, 140};28 __u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 4096 /* size */);29 30 if (!data)31 return 0; /* EPERM check */32 33 /* if not Keyboard */34 if (data[3] != 0x06)35 return 0;36 37 for (int idx = 0; idx < ARRAY_SIZE(offsets); idx++) {38 u8 offset = offsets[idx];39 40 /* if Input (Cnst,Var,Abs) , make it Input (Data,Var,Abs) */41 if (data[offset] == 0x81 && data[offset + 1] == 0x03)42 data[offset + 1] = 0x02;43 }44 45 return 0;46}47 48HID_BPF_OPS(iogear_kaliber_momentum) = {49 .hid_rdesc_fixup = (void *)hid_fix_rdesc,50};51 52SEC("syscall")53int probe(struct hid_bpf_probe_args *ctx)54{55 /* only bind to the keyboard interface */56 ctx->retval = ctx->rdesc_size != 213;57 if (ctx->retval)58 ctx->retval = -EINVAL;59 60 return 0;61}62 63char _license[] SEC("license") = "GPL";64