Files
LithosAnanke/kernel/include/starkernel/virtio_input.h
T
Claude 3bd81097e1 chore(license): an SPDX header on every source file that had none (LicenseRef-Starship-1.0) [skip ci]
The header scan (Captain Bob, 2026-11-10): 788 source files -- 351 with the
SL-1.0 header, 12 with the old name (docs/working/experiments, kept by
ruling), 31 under someone else's licence (tools/kconfig, Linux's, GPL-2.0:
kept), and 394 with none. Ruled: the SPDX form; capsules (.4th, .f18) and
proofs (.thy) left for a ruling of their own (mkcapsule's 64x16 block format,
content-addressed capsules).

253 files now begin
    SPDX-License-Identifier: LicenseRef-Starship-1.0
    Copyright (c) 2023-2026 Robert A. James
as a /* */ block (C, headers, assembly, linker scripts) or # lines (scripts,
Makefiles, Kconfig; below a shebang or a coding line); tools/mkcapsule.c,
which had the copyright line, gets the SPDX line only.

Not touched: docs/working/ (archive and old campaign material, as the
ruling kept the experiments); v4/system/post_cases.c (generated by
v4/tools/mkpost.py, "do not edit" -- the generator has the header).

Comments only: the kernel builds on amd64, aarch64, riscv64; make -C v4
test-32: 39 programs, 0 failures; every changed script parses.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GE3SDvQn5EoxdGufk84zz2
2026-11-10 04:12:49 +00:00

71 lines
2.9 KiB
C

/* SPDX-License-Identifier: LicenseRef-Starship-1.0
* Copyright (c) 2023-2026 Robert A. James
*/
/*
* virtio_input.h — Virtio 1.0 input device driver for StarKernel (item 4.3.5c)
*
* riscv64-only today (PCI transport, PLIC interrupt routing). aarch64's
* 4.3.5e reuses this device identity/event shape over the same PCI
* transport with GIC routing instead; riscv64/aarch64-specific pieces stay
* in their own arch trees, not here.
*
* Interrupt-driven end to end: the driver pre-posts empty event buffers
* into the eventq and the device fills+posts them asynchronously, signalled
* by the PLIC (via 4.3.5b's claim/complete substrate) — no polling.
*/
#ifndef STARKERNEL_VIRTIO_INPUT_H
#define STARKERNEL_VIRTIO_INPUT_H
#include <stdint.h>
/* virtio PCI vendor (same device family as virtio-blk) */
#define VIRTIO_INPUT_PCI_VENDOR_ID 0x1AF4u
/* Modern-ID formula 0x1040 + VIRTIO_ID_INPUT, VIRTIO_ID_INPUT = 18, per
* this build host's /usr/include/linux/virtio_ids.h. No legacy/transitional
* ID exists for virtio-input (postdates the legacy 0.9.5 spec). */
#define VIRTIO_INPUT_PCI_DEVICE_ID 0x1052u
/* struct virtio_input_event, per /usr/include/linux/virtio_input.h (BSD
* licensed, same wire format this driver decodes). */
typedef struct {
uint16_t type;
uint16_t code;
uint32_t value;
} VirtioInputEvent;
/* EV_KEY, per /usr/include/linux/input-event-codes.h */
#define VIRTIO_INPUT_EV_KEY 0x01u
/*
* virtio_input_find_keyboard — locate a virtio-keyboard-pci device on the
* PCI bus, initialise the driver, compute and
* enable its PLIC interrupt source (item
* 4.3.5c's own derivation, FABRIC-0.md §27.5.2),
* and pre-post the eventq's receive buffers.
*
* Returns 0 on success.
* Returns -1 if no virtio-keyboard-pci device was found on the PCI bus.
* Returns -2 on driver initialisation failure (bad BAR, queue setup, etc.).
*/
int virtio_input_find_keyboard(void);
/*
* virtio_input_isr — called from riscv64_interrupt_handler() when the PLIC
* claim matches this driver's computed source. Reads the
* ISR-status capability (mandatory — the routed source
* is level-triggered; skipping this leaves it latched),
* drains the used ring, pushes decoded EV_KEY events into
* the diagnostic ring buffer (keyboard_words.c), and
* re-posts drained buffers to the eventq's avail ring.
*/
void virtio_input_isr(void);
/*
* virtio_input_pop_event — diagnostic-ring consumer for keyboard_words.c's
* VKBD-EVENT, same shape as i8042_pop_scancode().
* Returns 1 and fills *code and *value if an event was available, 0 otherwise.
*/
int virtio_input_pop_event(uint16_t *code, uint32_t *value);
#endif /* STARKERNEL_VIRTIO_INPUT_H */