The Rapoo M50 Plus Silent mouse has 2 side buttons in addition to the
left, right and middles 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.

Link: https://gitlab.freedesktop.org/libinput/libinput/-/issues/1015
Link: https://gitlab.freedesktop.org/libevdev/udev-hid-bpf/-/merge_requests/116
Signed-off-by: José Expósito <jose.exposito89@gmail.com>
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>

---

no changes in v2
---
 drivers/hid/bpf/progs/Rapoo__M50-Plus-Silent.bpf.c | 148 +++++++++++++++++++++
 1 file changed, 148 insertions(+)

diff --git a/drivers/hid/bpf/progs/Rapoo__M50-Plus-Silent.bpf.c b/drivers/hid/bpf/progs/Rapoo__M50-Plus-Silent.bpf.c
new file mode 100644
index 0000000000000000000000000000000000000000..6b379e45f531dbe843fe59fd98cc12d3fd3c8cc8
--- /dev/null
+++ b/drivers/hid/bpf/progs/Rapoo__M50-Plus-Silent.bpf.c
@@ -0,0 +1,148 @@
+// 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";

-- 
2.47.0