| // SPDX-License-Identifier: GPL-2.0-only |
| /* Copyright (c) 2024 Benjamin Tissoires |
| */ |
| |
| #include "vmlinux.h" |
| #include "hid_bpf.h" |
| #include "hid_bpf_helpers.h" |
| #include <bpf/bpf_tracing.h> |
| |
| #define VID_BETOP_2185PC 0x11C0 |
| #define PID_RAPTOR_MACH_2 0x5606 |
| |
| HID_BPF_CONFIG( |
| HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, VID_BETOP_2185PC, PID_RAPTOR_MACH_2), |
| ); |
| |
| /* |
| * For reference, this is the fixed report descriptor |
| * |
| * static const __u8 fixed_rdesc[] = { |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 0 |
| * 0x09, 0x04, // Usage (Joystick) 2 |
| * 0xa1, 0x01, // Collection (Application) 4 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 6 |
| * 0x85, 0x01, // Report ID (1) 8 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 10 |
| * 0x09, 0x30, // Usage (X) 12 |
| * 0x75, 0x10, // Report Size (16) 14 |
| * 0x95, 0x01, // Report Count (1) 16 |
| * 0x15, 0x00, // Logical Minimum (0) 18 |
| * 0x26, 0xff, 0x07, // Logical Maximum (2047) 20 |
| * 0x46, 0xff, 0x07, // Physical Maximum (2047) 23 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 26 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 28 |
| * 0x09, 0x31, // Usage (Y) 30 |
| * 0x75, 0x10, // Report Size (16) 32 |
| * 0x95, 0x01, // Report Count (1) 34 |
| * 0x15, 0x00, // Logical Minimum (0) 36 |
| * 0x26, 0xff, 0x07, // Logical Maximum (2047) 38 |
| * 0x46, 0xff, 0x07, // Physical Maximum (2047) 41 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 44 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 46 |
| * 0x09, 0x33, // Usage (Rx) 48 |
| * 0x75, 0x10, // Report Size (16) 50 |
| * 0x95, 0x01, // Report Count (1) 52 |
| * 0x15, 0x00, // Logical Minimum (0) 54 |
| * 0x26, 0xff, 0x03, // Logical Maximum (1023) 56 |
| * 0x46, 0xff, 0x03, // Physical Maximum (1023) 59 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 62 |
| * 0x05, 0x00, // Usage Page (Undefined) 64 |
| * 0x09, 0x00, // Usage (Undefined) 66 |
| * 0x75, 0x10, // Report Size (16) 68 |
| * 0x95, 0x01, // Report Count (1) 70 |
| * 0x15, 0x00, // Logical Minimum (0) 72 |
| * 0x26, 0xff, 0x03, // Logical Maximum (1023) 74 |
| * 0x46, 0xff, 0x03, // Physical Maximum (1023) 77 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 80 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 82 |
| * 0x09, 0x32, // Usage (Z) 84 |
| * 0x75, 0x10, // Report Size (16) 86 |
| * 0x95, 0x01, // Report Count (1) 88 |
| * 0x15, 0x00, // Logical Minimum (0) 90 |
| * 0x26, 0xff, 0x03, // Logical Maximum (1023) 92 |
| * 0x46, 0xff, 0x03, // Physical Maximum (1023) 95 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 98 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 100 |
| * 0x09, 0x35, // Usage (Rz) 102 |
| * 0x75, 0x10, // Report Size (16) 104 |
| * 0x95, 0x01, // Report Count (1) 106 |
| * 0x15, 0x00, // Logical Minimum (0) 108 |
| * 0x26, 0xff, 0x03, // Logical Maximum (1023) 110 |
| * 0x46, 0xff, 0x03, // Physical Maximum (1023) 113 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 116 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 118 |
| * 0x09, 0x34, // Usage (Ry) 120 |
| * 0x75, 0x10, // Report Size (16) 122 |
| * 0x95, 0x01, // Report Count (1) 124 |
| * 0x15, 0x00, // Logical Minimum (0) 126 |
| * 0x26, 0xff, 0x07, // Logical Maximum (2047) 128 |
| * 0x46, 0xff, 0x07, // Physical Maximum (2047) 131 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 134 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 136 |
| * 0x09, 0x36, // Usage (Slider) 138 |
| * 0x75, 0x10, // Report Size (16) 140 |
| * 0x95, 0x01, // Report Count (1) 142 |
| * 0x15, 0x00, // Logical Minimum (0) 144 |
| * 0x26, 0xff, 0x03, // Logical Maximum (1023) 146 |
| * 0x46, 0xff, 0x03, // Physical Maximum (1023) 149 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 152 |
| * 0x05, 0x09, // Usage Page (Button) 154 |
| * 0x19, 0x01, // Usage Minimum (1) 156 |
| * 0x2a, 0x1d, 0x00, // Usage Maximum (29) 158 |
| * 0x15, 0x00, // Logical Minimum (0) 161 |
| * 0x25, 0x01, // Logical Maximum (1) 163 |
| * 0x75, 0x01, // Report Size (1) 165 |
| * 0x96, 0x80, 0x00, // Report Count (128) 167 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 170 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 172 |
| * 0x09, 0x39, // Usage (Hat switch) 174 |
| * 0x26, 0x07, 0x00, // Logical Maximum (7) 176 // changed (was 239) |
| * 0x46, 0x68, 0x01, // Physical Maximum (360) 179 |
| * 0x65, 0x14, // Unit (EnglishRotation: deg) 182 |
| * 0x75, 0x10, // Report Size (16) 184 |
| * 0x95, 0x01, // Report Count (1) 186 |
| * 0x81, 0x42, // Input (Data,Var,Abs,Null) 188 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 190 |
| * 0x09, 0x00, // Usage (Undefined) 192 |
| * 0x75, 0x08, // Report Size (8) 194 |
| * 0x95, 0x1d, // Report Count (29) 196 |
| * 0x81, 0x01, // Input (Cnst,Arr,Abs) 198 |
| * 0x15, 0x00, // Logical Minimum (0) 200 |
| * 0x26, 0xef, 0x00, // Logical Maximum (239) 202 |
| * 0x85, 0x58, // Report ID (88) 205 |
| * 0x26, 0xff, 0x00, // Logical Maximum (255) 207 |
| * 0x46, 0xff, 0x00, // Physical Maximum (255) 210 |
| * 0x75, 0x08, // Report Size (8) 213 |
| * 0x95, 0x3f, // Report Count (63) 215 |
| * 0x09, 0x00, // Usage (Undefined) 217 |
| * 0x91, 0x02, // Output (Data,Var,Abs) 219 |
| * 0x85, 0x59, // Report ID (89) 221 |
| * 0x75, 0x08, // Report Size (8) 223 |
| * 0x95, 0x80, // Report Count (128) 225 |
| * 0x09, 0x00, // Usage (Undefined) 227 |
| * 0xb1, 0x02, // Feature (Data,Var,Abs) 229 |
| * 0xc0, // End Collection 231 |
| * }; |
| */ |
| |
| /* |
| * We need to amend the report descriptor for the following: |
| * - the joystick sends its hat_switch data between 0 and 239 but |
| * the kernel expects the logical max to stick into a signed 8 bits |
| * integer. We thus divide it by 30 to match what other joysticks are |
| * doing |
| */ |
| SEC(HID_BPF_RDESC_FIXUP) |
| int BPF_PROG(hid_fix_rdesc_raptor_mach_2, struct hid_bpf_ctx *hctx) |
| { |
| __u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, HID_MAX_DESCRIPTOR_SIZE /* size */); |
| |
| if (!data) |
| return 0; /* EPERM check */ |
| |
| data[177] = 0x07; |
| |
| return 0; |
| } |
| |
| /* |
| * The hat_switch value at offsets 33 and 34 (16 bits) needs |
| * to be reduced to a single 8 bit signed integer. So we |
| * divide it by 30. |
| * Byte 34 is always null, so it is ignored. |
| */ |
| SEC(HID_BPF_DEVICE_EVENT) |
| int BPF_PROG(raptor_mach_2_fix_hat_switch, struct hid_bpf_ctx *hctx) |
| { |
| __u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 64 /* size */); |
| |
| if (!data) |
| return 0; /* EPERM check */ |
| |
| if (data[0] != 0x01) /* not the joystick report ID */ |
| return 0; |
| |
| data[33] /= 30; |
| |
| return 0; |
| } |
| |
| HID_BPF_OPS(raptor_mach_2) = { |
| .hid_rdesc_fixup = (void *)hid_fix_rdesc_raptor_mach_2, |
| .hid_device_event = (void *)raptor_mach_2_fix_hat_switch, |
| }; |
| |
| SEC("syscall") |
| int probe(struct hid_bpf_probe_args *ctx) |
| { |
| ctx->retval = ctx->rdesc_size != 232; |
| if (ctx->retval) |
| ctx->retval = -EINVAL; |
| |
| /* ensure the kernel isn't fixed already */ |
| if (ctx->rdesc[177] != 0xef) /* Logical Max of 239 */ |
| ctx->retval = -EINVAL; |
| |
| return 0; |
| } |
| |
| char _license[] SEC("license") = "GPL"; |
