drivers/hid/bpf/progs/XPPen__Deco01V3.bpf.c
Source file repositories/reference/linux-study-clean/drivers/hid/bpf/progs/XPPen__Deco01V3.bpf.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/hid/bpf/progs/XPPen__Deco01V3.bpf.c- Extension
.c- Size
- 14539 bytes
- Lines
- 306
- Domain
- Driver Families
- Bucket
- drivers/hid
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
vmlinux.hhid_bpf.hhid_bpf_helpers.hhid_report_helpers.hbpf/bpf_tracing.h
Detected Declarations
function BPF_PROGfunction BPF_PROGfunction probe
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2025 Red Hat
*/
#include "vmlinux.h"
#include "hid_bpf.h"
#include "hid_bpf_helpers.h"
#include "hid_report_helpers.h"
#include <bpf/bpf_tracing.h>
#define VID_UGEE 0x28BD /* VID is shared with SinoWealth and Glorious and prob others */
#define PID_DECO_01_V3 0x0947
HID_BPF_CONFIG(
HID_DEVICE(BUS_USB, HID_GROUP_GENERIC, VID_UGEE, PID_DECO_01_V3),
);
/*
* Default report descriptor reports:
* - a report descriptor for the pad buttons, reported as key sequences
* - a report descriptor for the pen
* - a vendor-specific report descriptor
*
* The Pad report descriptor, see
* https://gitlab.freedesktop.org/libevdev/udev-hid-bpf/-/issues/54
*
* # Report descriptor length: 102 bytes
* 0x05, 0x01, // Usage Page (Generic Desktop) 0
* 0x09, 0x02, // Usage (Mouse) 2
* 0xa1, 0x01, // Collection (Application) 4
* 0x85, 0x09, // Report ID (9) 6
* 0x09, 0x01, // Usage (Pointer) 8
* 0xa1, 0x00, // Collection (Physical) 10
* 0x05, 0x09, // Usage Page (Button) 12
* 0x19, 0x01, // UsageMinimum (1) 14
* 0x29, 0x03, // UsageMaximum (3) 16
* 0x15, 0x00, // Logical Minimum (0) 18
* 0x25, 0x01, // Logical Maximum (1) 20
* 0x95, 0x03, // Report Count (3) 22
* 0x75, 0x01, // Report Size (1) 24
* 0x81, 0x02, // Input (Data,Var,Abs) 26
* 0x95, 0x05, // Report Count (5) 28
* 0x81, 0x01, // Input (Cnst,Arr,Abs) 30
* 0x05, 0x01, // Usage Page (Generic Desktop) 32
* 0x09, 0x30, // Usage (X) 34
* 0x09, 0x31, // Usage (Y) 36
* 0x26, 0xff, 0x7f, // Logical Maximum (32767) 38
* 0x95, 0x02, // Report Count (2) 41
* 0x75, 0x10, // Report Size (16) 43
* 0x81, 0x02, // Input (Data,Var,Abs) 45
* 0x05, 0x0d, // Usage Page (Digitizers) 47
* 0x09, 0x30, // Usage (Tip Pressure) 49
* 0x26, 0xff, 0x07, // Logical Maximum (2047) 51
* 0x95, 0x01, // Report Count (1) 54
* 0x75, 0x10, // Report Size (16) 56
* 0x81, 0x02, // Input (Data,Var,Abs) 58
* 0xc0, // End Collection 60
* 0xc0, // End Collection 61
* 0x05, 0x01, // Usage Page (Generic Desktop) 62
* 0x09, 0x06, // Usage (Keyboard) 64
* 0xa1, 0x01, // Collection (Application) 66
* 0x85, 0x06, // Report ID (6) 68
* 0x05, 0x07, // Usage Page (Keyboard/Keypad) 70
* 0x19, 0xe0, // UsageMinimum (224) 72
* 0x29, 0xe7, // UsageMaximum (231) 74
* 0x15, 0x00, // Logical Minimum (0) 76
* 0x25, 0x01, // Logical Maximum (1) 78
* 0x75, 0x01, // Report Size (1) 80
* 0x95, 0x08, // Report Count (8) 82
* 0x81, 0x02, // Input (Data,Var,Abs) 84
* 0x05, 0x07, // Usage Page (Keyboard/Keypad) 86
* 0x19, 0x00, // UsageMinimum (0) 88
* 0x29, 0xff, // UsageMaximum (255) 90
* 0x26, 0xff, 0x00, // Logical Maximum (255) 92
* 0x75, 0x08, // Report Size (8) 95
* 0x95, 0x06, // Report Count (6) 97
* 0x81, 0x00, // Input (Data,Arr,Abs) 99
* 0xc0, // End Collection 101
*
* And key events for buttons top->bottom are:
* Buttons released: 06 00 00 00 00 00 00 00
* Button1: 06 00 05 00 00 00 00 00 -> b
* Button2: 06 00 08 00 00 00 00 00 -> e
* Button3: 06 04 00 00 00 00 00 00 -> LAlt
* Button4: 06 00 2c 00 00 00 00 00 -> Space
* Button5: 06 01 16 00 00 00 00 00 -> LControl + s
* Button6: 06 01 1d 00 00 00 00 00 -> LControl + z
* Button7: 06 01 57 00 00 00 00 00 -> LControl + Keypad Plus
* Button8: 06 01 56 00 00 00 00 00 -> LControl + Keypad Dash
*Annotation
- Immediate include surface: `vmlinux.h`, `hid_bpf.h`, `hid_bpf_helpers.h`, `hid_report_helpers.h`, `bpf/bpf_tracing.h`.
- Detected declarations: `function BPF_PROG`, `function BPF_PROG`, `function probe`.
- Atlas domain: Driver Families / drivers/hid.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.