stm32/adc: add async conversion

This commit is contained in:
xoviat 2023-09-18 16:31:20 -05:00
parent daeb497045
commit e640933e2f
3 changed files with 109 additions and 18 deletions

View File

@ -1,14 +1,36 @@
use core::future::poll_fn;
use core::marker::PhantomData;
use core::task::Poll;
use embassy_hal_internal::into_ref;
use embedded_hal_02::blocking::delay::DelayUs;
use crate::adc::{Adc, AdcPin, Instance, SampleTime};
use crate::interrupt::typelevel::Interrupt;
use crate::time::Hertz;
use crate::Peripheral;
use crate::{interrupt, Peripheral};
pub const VDDA_CALIB_MV: u32 = 3300;
pub const ADC_MAX: u32 = (1 << 12) - 1;
pub const VREF_INT: u32 = 1230;
/// Interrupt handler.
pub struct InterruptHandler<T: Instance> {
_phantom: PhantomData<T>,
}
impl<T: Instance> interrupt::typelevel::Handler<T::Interrupt> for InterruptHandler<T> {
unsafe fn on_interrupt() {
if T::regs().isr().read().eoc() {
T::regs().ier().modify(|w| w.set_eocie(false));
} else {
return;
}
T::state().waker.wake();
}
}
pub struct Vref;
impl<T: Instance> AdcPin<T> for Vref {}
impl<T: Instance> super::sealed::AdcPin<T> for Vref {
@ -17,6 +39,13 @@ impl<T: Instance> super::sealed::AdcPin<T> for Vref {
}
}
impl Vref {
/// The value that vref would be if vdda was at 3300mv
pub fn value(&self) -> u16 {
crate::pac::VREFINTCAL.data().read().value()
}
}
pub struct Temperature;
impl<T: Instance> AdcPin<T> for Temperature {}
impl<T: Instance> super::sealed::AdcPin<T> for Temperature {
@ -26,7 +55,11 @@ impl<T: Instance> super::sealed::AdcPin<T> for Temperature {
}
impl<'d, T: Instance> Adc<'d, T> {
pub fn new(adc: impl Peripheral<P = T> + 'd, delay: &mut impl DelayUs<u32>) -> Self {
pub fn new(
adc: impl Peripheral<P = T> + 'd,
_irq: impl interrupt::typelevel::Binding<T::Interrupt, InterruptHandler<T>> + 'd,
delay: &mut impl DelayUs<u32>,
) -> Self {
use crate::pac::adc::vals;
into_ref!(adc);
@ -58,6 +91,11 @@ impl<'d, T: Instance> Adc<'d, T> {
// Wait until the adc is ready
while !T::regs().isr().read().adrdy() {}
T::Interrupt::unpend();
unsafe {
T::Interrupt::enable();
}
Self {
adc,
sample_time: Default::default(),
@ -97,30 +135,41 @@ impl<'d, T: Instance> Adc<'d, T> {
}
/// Perform a single conversion.
fn convert(&mut self) -> u16 {
async fn convert(&mut self) -> u16 {
T::regs().isr().write(|_| {});
T::regs().ier().modify(|w| w.set_eocie(true));
T::regs().cr().modify(|w| w.set_adstart(true));
while !T::regs().isr().read().eoc() && !T::regs().isr().read().eos() {}
poll_fn(|cx| {
T::state().waker.register(cx.waker());
if T::regs().isr().read().eoc() {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
T::regs().isr().write(|_| {});
T::regs().dr().read().rdata()
}
pub fn read(&mut self, pin: &mut impl AdcPin<T>) -> u16 {
pub async fn read(&mut self, pin: &mut impl AdcPin<T>) -> u16 {
Self::set_channel_sample_time(pin.channel(), self.sample_time);
// Configure the channel to sample
T::regs().sqr1().write(|w| w.set_sq(0, pin.channel()));
self.convert()
self.convert().await
}
fn set_channel_sample_time(ch: u8, sample_time: SampleTime) {
let sample_time = sample_time.into();
if ch <= 9 {
T::regs().smpr2().modify(|reg| reg.set_smp(ch as _, sample_time));
T::regs().smpr1().modify(|reg| reg.set_smp(ch as _, sample_time));
} else {
T::regs().smpr1().modify(|reg| reg.set_smp((ch - 10) as _, sample_time));
T::regs().smpr2().modify(|reg| reg.set_smp((ch - 10) as _, sample_time));
}
}
}

View File

@ -31,12 +31,35 @@ pub struct Adc<'d, T: Instance> {
}
pub(crate) mod sealed {
pub trait Instance {
#[cfg(adc_f3)]
use embassy_sync::waitqueue::AtomicWaker;
#[cfg(adc_f3)]
pub struct State {
pub waker: AtomicWaker,
}
#[cfg(adc_f3)]
impl State {
pub const fn new() -> Self {
Self {
waker: AtomicWaker::new(),
}
}
}
pub trait InterruptableInstance {
type Interrupt: crate::interrupt::typelevel::Interrupt;
}
pub trait Instance: InterruptableInstance {
fn regs() -> crate::pac::adc::Adc;
#[cfg(not(any(adc_f1, adc_v1, adc_f3_v2, adc_g0)))]
fn common_regs() -> crate::pac::adccommon::AdcCommon;
#[cfg(adc_f3)]
fn frequency() -> crate::time::Hertz;
#[cfg(adc_f3)]
fn state() -> &'static State;
}
pub trait AdcPin<T: Instance> {
@ -72,7 +95,21 @@ foreach_adc!(
fn frequency() -> crate::time::Hertz {
unsafe { crate::rcc::get_freqs() }.$clock.unwrap()
}
#[cfg(adc_f3)]
fn state() -> &'static sealed::State {
static STATE: sealed::State = sealed::State::new();
&STATE
}
}
foreach_interrupt!(
($inst,adc,ADC,GLOBAL,$irq:ident) => {
impl sealed::InterruptableInstance for peripherals::$inst {
type Interrupt = crate::interrupt::typelevel::$irq;
}
};
);
impl crate::adc::Instance for peripherals::$inst {}
};

View File

@ -4,13 +4,18 @@
use defmt::info;
use embassy_executor::Spawner;
use embassy_stm32::adc::{Adc, SampleTime, VREF_INT};
use embassy_stm32::adc::{Adc, SampleTime};
use embassy_stm32::peripherals::ADC1;
use embassy_stm32::rcc::AdcClockSource;
use embassy_stm32::time::mhz;
use embassy_stm32::Config;
use embassy_stm32::{adc, bind_interrupts, Config};
use embassy_time::{Delay, Duration, Timer};
use {defmt_rtt as _, panic_probe as _};
bind_interrupts!(struct Irqs {
ADC1_2 => adc::InterruptHandler<ADC1>;
});
#[embassy_executor::main]
async fn main(_spawner: Spawner) -> ! {
let mut config = Config::default();
@ -24,7 +29,7 @@ async fn main(_spawner: Spawner) -> ! {
info!("create adc...");
let mut adc = Adc::new(p.ADC1, &mut Delay);
let mut adc = Adc::new(p.ADC1, Irqs, &mut Delay);
adc.set_sample_time(SampleTime::Cycles601_5);
@ -34,18 +39,18 @@ async fn main(_spawner: Spawner) -> ! {
let mut temperature = adc.enable_temperature();
loop {
let vref = adc.read(&mut vrefint);
info!("read vref: {}", vref);
let vref = adc.read(&mut vrefint).await;
info!("read vref: {} (should be {})", vref, vrefint.value());
let temp = adc.read(&mut temperature);
let temp = adc.read(&mut temperature).await;
info!("read temperature: {}", temp);
let pin = adc.read(&mut p.PA0);
let pin = adc.read(&mut p.PA0).await;
info!("read pin: {}", pin);
let pin_mv = pin as u32 * VREF_INT as u32 / vref as u32;
let pin_mv = (pin as u32 * vrefint.value() as u32 / vref as u32) * 3300 / 4095;
info!("computed pin mv: {}", pin_mv);
Timer::after(Duration::from_secs(1)).await;
Timer::after(Duration::from_millis(500)).await;
}
}