| // SPDX-License-Identifier: GPL-2.0-only |
| /* Copyright (c) 2024 José Expósito |
| */ |
| |
| #include "vmlinux.h" |
| #include "hid_bpf.h" |
| #include "hid_bpf_helpers.h" |
| #include <bpf/bpf_tracing.h> |
| |
| #define VID_RAPOO 0x24AE |
| #define PID_M50 0x2015 |
| #define RDESC_SIZE 186 |
| |
| HID_BPF_CONFIG( |
| HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, VID_RAPOO, PID_M50) |
| ); |
| |
| /* |
| * The Rapoo M50 Plus Silent mouse has 2 side buttons in addition to the left, |
| * right and middle buttons. However, its original HID descriptor has a Usage |
| * Maximum of 3, preventing the side buttons to work. This HID-BPF driver |
| * changes that usage to 5. |
| * |
| * For reference, this is the original report descriptor: |
| * |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 0 |
| * 0x09, 0x02, // Usage (Mouse) 2 |
| * 0xa1, 0x01, // Collection (Application) 4 |
| * 0x85, 0x01, // Report ID (1) 6 |
| * 0x09, 0x01, // Usage (Pointer) 8 |
| * 0xa1, 0x00, // Collection (Physical) 10 |
| * 0x05, 0x09, // Usage Page (Button) 12 |
| * 0x19, 0x01, // Usage Minimum (1) 14 |
| * 0x29, 0x03, // Usage Maximum (3) 16 <- change to 0x05 |
| * 0x15, 0x00, // Logical Minimum (0) 18 |
| * 0x25, 0x01, // Logical Maximum (1) 20 |
| * 0x75, 0x01, // Report Size (1) 22 |
| * 0x95, 0x05, // Report Count (5) 24 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 26 |
| * 0x75, 0x03, // Report Size (3) 28 |
| * 0x95, 0x01, // Report Count (1) 30 |
| * 0x81, 0x01, // Input (Cnst,Arr,Abs) 32 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 34 |
| * 0x09, 0x30, // Usage (X) 36 |
| * 0x09, 0x31, // Usage (Y) 38 |
| * 0x16, 0x01, 0x80, // Logical Minimum (-32767) 40 |
| * 0x26, 0xff, 0x7f, // Logical Maximum (32767) 43 |
| * 0x75, 0x10, // Report Size (16) 46 |
| * 0x95, 0x02, // Report Count (2) 48 |
| * 0x81, 0x06, // Input (Data,Var,Rel) 50 |
| * 0x09, 0x38, // Usage (Wheel) 52 |
| * 0x15, 0x81, // Logical Minimum (-127) 54 |
| * 0x25, 0x7f, // Logical Maximum (127) 56 |
| * 0x75, 0x08, // Report Size (8) 58 |
| * 0x95, 0x01, // Report Count (1) 60 |
| * 0x81, 0x06, // Input (Data,Var,Rel) 62 |
| * 0xc0, // End Collection 64 |
| * 0xc0, // End Collection 65 |
| * 0x05, 0x0c, // Usage Page (Consumer Devices) 66 |
| * 0x09, 0x01, // Usage (Consumer Control) 68 |
| * 0xa1, 0x01, // Collection (Application) 70 |
| * 0x85, 0x02, // Report ID (2) 72 |
| * 0x75, 0x10, // Report Size (16) 74 |
| * 0x95, 0x01, // Report Count (1) 76 |
| * 0x15, 0x01, // Logical Minimum (1) 78 |
| * 0x26, 0x8c, 0x02, // Logical Maximum (652) 80 |
| * 0x19, 0x01, // Usage Minimum (1) 83 |
| * 0x2a, 0x8c, 0x02, // Usage Maximum (652) 85 |
| * 0x81, 0x00, // Input (Data,Arr,Abs) 88 |
| * 0xc0, // End Collection 90 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 91 |
| * 0x09, 0x80, // Usage (System Control) 93 |
| * 0xa1, 0x01, // Collection (Application) 95 |
| * 0x85, 0x03, // Report ID (3) 97 |
| * 0x09, 0x82, // Usage (System Sleep) 99 |
| * 0x09, 0x81, // Usage (System Power Down) 101 |
| * 0x09, 0x83, // Usage (System Wake Up) 103 |
| * 0x15, 0x00, // Logical Minimum (0) 105 |
| * 0x25, 0x01, // Logical Maximum (1) 107 |
| * 0x19, 0x01, // Usage Minimum (1) 109 |
| * 0x29, 0x03, // Usage Maximum (3) 111 |
| * 0x75, 0x01, // Report Size (1) 113 |
| * 0x95, 0x03, // Report Count (3) 115 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 117 |
| * 0x95, 0x05, // Report Count (5) 119 |
| * 0x81, 0x01, // Input (Cnst,Arr,Abs) 121 |
| * 0xc0, // End Collection 123 |
| * 0x05, 0x01, // Usage Page (Generic Desktop) 124 |
| * 0x09, 0x00, // Usage (Undefined) 126 |
| * 0xa1, 0x01, // Collection (Application) 128 |
| * 0x85, 0x05, // Report ID (5) 130 |
| * 0x06, 0x00, 0xff, // Usage Page (Vendor Defined Page 1) 132 |
| * 0x09, 0x01, // Usage (Vendor Usage 1) 135 |
| * 0x15, 0x81, // Logical Minimum (-127) 137 |
| * 0x25, 0x7f, // Logical Maximum (127) 139 |
| * 0x75, 0x08, // Report Size (8) 141 |
| * 0x95, 0x07, // Report Count (7) 143 |
| * 0xb1, 0x02, // Feature (Data,Var,Abs) 145 |
| * 0xc0, // End Collection 147 |
| * 0x06, 0x00, 0xff, // Usage Page (Vendor Defined Page 1) 148 |
| * 0x09, 0x0e, // Usage (Vendor Usage 0x0e) 151 |
| * 0xa1, 0x01, // Collection (Application) 153 |
| * 0x85, 0xba, // Report ID (186) 155 |
| * 0x95, 0x1f, // Report Count (31) 157 |
| * 0x75, 0x08, // Report Size (8) 159 |
| * 0x26, 0xff, 0x00, // Logical Maximum (255) 161 |
| * 0x15, 0x00, // Logical Minimum (0) 164 |
| * 0x09, 0x01, // Usage (Vendor Usage 1) 166 |
| * 0x91, 0x02, // Output (Data,Var,Abs) 168 |
| * 0x85, 0xba, // Report ID (186) 170 |
| * 0x95, 0x1f, // Report Count (31) 172 |
| * 0x75, 0x08, // Report Size (8) 174 |
| * 0x26, 0xff, 0x00, // Logical Maximum (255) 176 |
| * 0x15, 0x00, // Logical Minimum (0) 179 |
| * 0x09, 0x01, // Usage (Vendor Usage 1) 181 |
| * 0x81, 0x02, // Input (Data,Var,Abs) 183 |
| * 0xc0, // End Collection 185 |
| */ |
| |
| SEC(HID_BPF_RDESC_FIXUP) |
| int BPF_PROG(hid_rdesc_fixup_rapoo_m50, struct hid_bpf_ctx *hctx) |
| { |
| __u8 *data = hid_bpf_get_data(hctx, 0, HID_MAX_DESCRIPTOR_SIZE); |
| |
| if (!data) |
| return 0; /* EPERM check */ |
| |
| if (data[17] == 0x03) |
| data[17] = 0x05; |
| |
| return 0; |
| } |
| |
| HID_BPF_OPS(rapoo_m50) = { |
| .hid_rdesc_fixup = (void *)hid_rdesc_fixup_rapoo_m50, |
| }; |
| |
| SEC("syscall") |
| int probe(struct hid_bpf_probe_args *ctx) |
| { |
| ctx->retval = ctx->rdesc_size != RDESC_SIZE; |
| if (ctx->retval) |
| ctx->retval = -EINVAL; |
| |
| return 0; |
| } |
| |
| char _license[] SEC("license") = "GPL"; |
