embassy/src/ioctl.rs
Dario Nieuwenhuis c19de29847
Merge pull request #63 from kbleeke/generalize-events
rework event handling to allow sending data to `Control`
2023-04-27 18:23:36 +00:00

127 lines
3.0 KiB
Rust

use core::cell::{Cell, RefCell};
use core::future::poll_fn;
use core::task::{Poll, Waker};
use embassy_sync::waitqueue::WakerRegistration;
use crate::fmt::Bytes;
#[derive(Clone, Copy)]
pub enum IoctlType {
Get = 0,
Set = 2,
}
#[derive(Clone, Copy)]
pub struct PendingIoctl {
pub buf: *mut [u8],
pub kind: IoctlType,
pub cmd: u32,
pub iface: u32,
}
#[derive(Clone, Copy)]
enum IoctlStateInner {
Pending(PendingIoctl),
Sent { buf: *mut [u8] },
Done { resp_len: usize },
}
struct Wakers {
control: WakerRegistration,
runner: WakerRegistration,
}
impl Default for Wakers {
fn default() -> Self {
Self {
control: WakerRegistration::new(),
runner: WakerRegistration::new(),
}
}
}
pub struct IoctlState {
state: Cell<IoctlStateInner>,
wakers: RefCell<Wakers>,
}
impl IoctlState {
pub fn new() -> Self {
Self {
state: Cell::new(IoctlStateInner::Done { resp_len: 0 }),
wakers: Default::default(),
}
}
fn wake_control(&self) {
self.wakers.borrow_mut().control.wake();
}
fn register_control(&self, waker: &Waker) {
self.wakers.borrow_mut().control.register(waker);
}
fn wake_runner(&self) {
self.wakers.borrow_mut().runner.wake();
}
fn register_runner(&self, waker: &Waker) {
self.wakers.borrow_mut().runner.register(waker);
}
pub async fn wait_complete(&self) -> usize {
poll_fn(|cx| {
if let IoctlStateInner::Done { resp_len } = self.state.get() {
Poll::Ready(resp_len)
} else {
self.register_control(cx.waker());
Poll::Pending
}
})
.await
}
pub async fn wait_pending(&self) -> PendingIoctl {
let pending = poll_fn(|cx| {
if let IoctlStateInner::Pending(pending) = self.state.get() {
Poll::Ready(pending)
} else {
self.register_runner(cx.waker());
Poll::Pending
}
})
.await;
self.state.set(IoctlStateInner::Sent { buf: pending.buf });
pending
}
pub fn cancel_ioctl(&self) {
self.state.set(IoctlStateInner::Done { resp_len: 0 });
}
pub async fn do_ioctl(&self, kind: IoctlType, cmd: u32, iface: u32, buf: &mut [u8]) -> usize {
self.state
.set(IoctlStateInner::Pending(PendingIoctl { buf, kind, cmd, iface }));
self.wake_runner();
self.wait_complete().await
}
pub fn ioctl_done(&self, response: &[u8]) {
if let IoctlStateInner::Sent { buf } = self.state.get() {
info!("IOCTL Response: {:02x}", Bytes(response));
// TODO fix this
(unsafe { &mut *buf }[..response.len()]).copy_from_slice(response);
self.state.set(IoctlStateInner::Done {
resp_len: response.len(),
});
self.wake_control();
} else {
warn!("IOCTL Response but no pending Ioctl");
}
}
}