[PATCH 09/18] HID: bpf: add in-tree HID-BPF fix for the Raptor Mach 2
From: Benjamin Tissoires
Date: Wed Apr 10 2024 - 13:22:21 EST
This device is already fixed by "HID: do not assume HAT Switch
logical max < 8", but for people without the fix already, having the
HID-BPF locally can fix the device while they wait for their
distribution to update.
Signed-off-by: Benjamin Tissoires <bentiss@xxxxxxxxxx>
---
drivers/hid/bpf/progs/FR-TEC__Raptor-Mach-2.bpf.c | 185 ++++++++++++++++++++++
1 file changed, 185 insertions(+)
diff --git a/drivers/hid/bpf/progs/FR-TEC__Raptor-Mach-2.bpf.c b/drivers/hid/bpf/progs/FR-TEC__Raptor-Mach-2.bpf.c
new file mode 100644
index 000000000000..dc26a7677d36
--- /dev/null
+++ b/drivers/hid/bpf/progs/FR-TEC__Raptor-Mach-2.bpf.c
@@ -0,0 +1,185 @@
+// 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("fmod_ret/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("fmod_ret/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;
+}
+
+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";
--
2.44.0