From 54b39ba49237f315e757ede8ef97ca88118ea807 Mon Sep 17 00:00:00 2001 From: Ivan Li Date: Sat, 23 Nov 2024 12:30:09 +0800 Subject: [PATCH 1/2] stm32 adc g4 async read Signed-off-by: Ivan Li --- embassy-stm32/src/adc/g4.rs | 171 +++++++++++++++++++++++++++++++++--- 1 file changed, 160 insertions(+), 11 deletions(-) diff --git a/embassy-stm32/src/adc/g4.rs b/embassy-stm32/src/adc/g4.rs index 3e9ba8ae2..872cf3f06 100644 --- a/embassy-stm32/src/adc/g4.rs +++ b/embassy-stm32/src/adc/g4.rs @@ -5,8 +5,11 @@ use pac::adc::vals::{Adcaldif, Difsel, Exten}; #[cfg(stm32g4)] use pac::adc::vals::{Adcaldif, Difsel, Exten, Rovsm, Trovs}; use pac::adccommon::vals::Presc; +use stm32_metapac::adc::vals::{Adstp, Dmacfg, Dmaen}; -use super::{blocking_delay_us, Adc, AdcChannel, Instance, Resolution, SampleTime}; +use super::{blocking_delay_us, Adc, AdcChannel, AnyAdcChannel, Instance, Resolution, RxDma, SampleTime}; +use crate::adc::SealedAdcChannel; +use crate::dma::Transfer; use crate::time::Hertz; use crate::{pac, rcc, Peripheral}; @@ -191,10 +194,24 @@ impl<'d, T: Instance> Adc<'d, T> { } fn enable(&mut self) { - T::regs().isr().write(|w| w.set_adrdy(true)); - T::regs().cr().modify(|w| w.set_aden(true)); - while !T::regs().isr().read().adrdy() {} - T::regs().isr().write(|w| w.set_adrdy(true)); + // Make sure bits are off + while T::regs().cr().read().addis() { + // spin + } + + if !T::regs().cr().read().aden() { + // Enable ADC + T::regs().isr().modify(|reg| { + reg.set_adrdy(true); + }); + T::regs().cr().modify(|reg| { + reg.set_aden(true); + }); + + while !T::regs().isr().read().adrdy() { + // spin + } + } } fn configure(&mut self) { @@ -327,23 +344,146 @@ impl<'d, T: Instance> Adc<'d, T> { pub fn blocking_read(&mut self, channel: &mut impl AdcChannel) -> u16 { channel.setup(); - self.read_channel(channel.channel()) + self.read_channel(channel) } - fn read_channel(&mut self, channel: u8) -> u16 { - // Configure channel - Self::set_channel_sample_time(channel, self.sample_time); + /// Read one or multiple ADC channels using DMA. + /// + /// `sequence` iterator and `readings` must have the same length. + /// + /// Example + /// ```rust,ignore + /// use embassy_stm32::adc::{Adc, AdcChannel} + /// + /// let mut adc = Adc::new(p.ADC1); + /// let mut adc_pin0 = p.PA0.degrade_adc(); + /// let mut adc_pin1 = p.PA1.degrade_adc(); + /// let mut measurements = [0u16; 2]; + /// + /// adc.read_async( + /// p.DMA1_CH2, + /// [ + /// (&mut *adc_pin0, SampleTime::CYCLES160_5), + /// (&mut *adc_pin1, SampleTime::CYCLES160_5), + /// ] + /// .into_iter(), + /// &mut measurements, + /// ) + /// .await; + /// defmt::info!("measurements: {}", measurements); + /// ``` + pub async fn read( + &mut self, + rx_dma: &mut impl RxDma, + sequence: impl ExactSizeIterator, SampleTime)>, + readings: &mut [u16], + ) { + assert!(sequence.len() != 0, "Asynchronous read sequence cannot be empty"); + assert!( + sequence.len() == readings.len(), + "Sequence length must be equal to readings length" + ); + assert!( + sequence.len() <= 16, + "Asynchronous read sequence cannot be more than 16 in length" + ); + // Ensure no conversions are ongoing and ADC is enabled. + Self::cancel_conversions(); + self.enable(); + + // Set sequence length + T::regs().sqr1().modify(|w| { + w.set_l(sequence.len() as u8 - 1); + }); + + // Configure channels and ranks + for (_i, (channel, sample_time)) in sequence.enumerate() { + Self::configure_channel(channel, sample_time); + + match _i { + 0..=3 => { + T::regs().sqr1().modify(|w| { + w.set_sq(_i, channel.channel()); + }); + } + 4..=8 => { + T::regs().sqr2().modify(|w| { + w.set_sq(_i - 4, channel.channel()); + }); + } + 9..=13 => { + T::regs().sqr3().modify(|w| { + w.set_sq(_i - 9, channel.channel()); + }); + } + 14..=15 => { + T::regs().sqr4().modify(|w| { + w.set_sq(_i - 14, channel.channel()); + }); + } + _ => unreachable!(), + } + } + + // Set continuous mode with oneshot dma. + // Clear overrun flag before starting transfer. + T::regs().isr().modify(|reg| { + reg.set_ovr(true); + }); + + T::regs().cfgr().modify(|reg| { + reg.set_discen(false); + reg.set_cont(true); + reg.set_dmacfg(Dmacfg::ONESHOT); + reg.set_dmaen(Dmaen::ENABLE); + }); + + let request = rx_dma.request(); + let transfer = unsafe { + Transfer::new_read( + rx_dma, + request, + T::regs().dr().as_ptr() as *mut u16, + readings, + Default::default(), + ) + }; + + // Start conversion + T::regs().cr().modify(|reg| { + reg.set_adstart(true); + }); + + // Wait for conversion sequence to finish. + transfer.await; + + // Ensure conversions are finished. + Self::cancel_conversions(); + + // Reset configuration. + T::regs().cfgr().modify(|reg| { + reg.set_cont(false); + }); + } + + fn configure_channel(channel: &mut impl AdcChannel, sample_time: SampleTime) { + // Configure channel + Self::set_channel_sample_time(channel.channel(), sample_time); + } + + fn read_channel(&mut self, channel: &mut impl AdcChannel) -> u16 { + Self::configure_channel(channel, self.sample_time); #[cfg(stm32h7)] { T::regs().cfgr2().modify(|w| w.set_lshift(0)); T::regs() .pcsel() - .write(|w| w.set_pcsel(channel as _, Pcsel::PRESELECTED)); + .write(|w| w.set_pcsel(channel.channel() as _, Pcsel::PRESELECTED)); } T::regs().sqr1().write(|reg| { - reg.set_sq(0, channel); + reg.set_sq(0, channel.channel()); reg.set_l(0); }); @@ -358,4 +498,13 @@ impl<'d, T: Instance> Adc<'d, T> { T::regs().smpr2().modify(|reg| reg.set_smp((ch - 10) as _, sample_time)); } } + + fn cancel_conversions() { + if T::regs().cr().read().adstart() && !T::regs().cr().read().addis() { + T::regs().cr().modify(|reg| { + reg.set_adstp(Adstp::STOP); + }); + while T::regs().cr().read().adstart() {} + } + } } From b1bbe6bcf21b5e89f9abb15abbece7063127f303 Mon Sep 17 00:00:00 2001 From: Ivan Li Date: Sat, 23 Nov 2024 12:47:56 +0800 Subject: [PATCH 2/2] stm32 adc g4: example of async read Signed-off-by: Ivan Li --- examples/stm32g4/src/bin/adc_dma.rs | 60 +++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 examples/stm32g4/src/bin/adc_dma.rs diff --git a/examples/stm32g4/src/bin/adc_dma.rs b/examples/stm32g4/src/bin/adc_dma.rs new file mode 100644 index 000000000..970623b32 --- /dev/null +++ b/examples/stm32g4/src/bin/adc_dma.rs @@ -0,0 +1,60 @@ +#![no_std] +#![no_main] + +use defmt::*; +use embassy_executor::Spawner; +use embassy_stm32::adc::{Adc, AdcChannel as _, SampleTime}; +use embassy_stm32::Config; +use embassy_time::Timer; +use {defmt_rtt as _, panic_probe as _}; + +static mut DMA_BUF: [u16; 2] = [0; 2]; + +#[embassy_executor::main] +async fn main(_spawner: Spawner) { + let mut read_buffer = unsafe { &mut DMA_BUF[..] }; + + let mut config = Config::default(); + { + use embassy_stm32::rcc::*; + config.rcc.pll = Some(Pll { + source: PllSource::HSI, + prediv: PllPreDiv::DIV4, + mul: PllMul::MUL85, + divp: None, + divq: None, + // Main system clock at 170 MHz + divr: Some(PllRDiv::DIV2), + }); + config.rcc.mux.adc12sel = mux::Adcsel::SYS; + config.rcc.sys = Sysclk::PLL1_R; + } + let p = embassy_stm32::init(config); + + info!("Hello World!"); + + let mut adc = Adc::new(p.ADC1); + + let mut dma = p.DMA1_CH1; + let mut vrefint_channel = adc.enable_vrefint().degrade_adc(); + let mut pa0 = p.PA0.degrade_adc(); + + loop { + adc.read( + &mut dma, + [ + (&mut vrefint_channel, SampleTime::CYCLES247_5), + (&mut pa0, SampleTime::CYCLES247_5), + ] + .into_iter(), + &mut read_buffer, + ) + .await; + + let vrefint = read_buffer[0]; + let measured = read_buffer[1]; + info!("vrefint: {}", vrefint); + info!("measured: {}", measured); + Timer::after_millis(500).await; + } +}