add docs, cleanup

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JuliDi 2023-06-25 11:54:25 +02:00
parent df944edeef
commit 8cafaa1f3c
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@ -1,5 +1,6 @@
#![macro_use]
//! Provide access to the STM32 digital-to-analog converter (DAC).
use core::marker::PhantomData;
use embassy_hal_common::{into_ref, PeripheralRef};
@ -11,6 +12,7 @@ use crate::{peripherals, Peripheral};
#[derive(Debug, Copy, Clone, Eq, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
/// Curstom Errors
pub enum Error {
UnconfiguredChannel,
InvalidValue,
@ -18,6 +20,7 @@ pub enum Error {
#[derive(Debug, Copy, Clone, Eq, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
/// DAC Channels
pub enum Channel {
Ch1,
Ch2,
@ -34,6 +37,7 @@ impl Channel {
#[derive(Debug, Copy, Clone, Eq, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
/// Trigger sources for CH1
pub enum Ch1Trigger {
Tim6,
Tim3,
@ -60,6 +64,7 @@ impl Ch1Trigger {
#[derive(Debug, Copy, Clone, Eq, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
/// Trigger sources for CH2
pub enum Ch2Trigger {
Tim6,
Tim8,
@ -109,7 +114,7 @@ pub enum ValueArray<'a> {
// 12 bit values stored in a u16, right-aligned
Bit12Right(&'a [u16]),
}
/// Provide common functions for DAC channels
pub trait DacChannel<T: Instance, Tx> {
const CHANNEL: Channel;
@ -157,7 +162,7 @@ pub trait DacChannel<T: Instance, Tx> {
/// Set a value to be output by the DAC on trigger.
///
/// The `value` is written to the corresponding "data holding register"
/// The `value` is written to the corresponding "data holding register".
fn set(&mut self, value: Value) -> Result<(), Error> {
match value {
Value::Bit8(v) => T::regs().dhr8r(Self::CHANNEL.index()).write(|reg| reg.set_dhr(v)),
@ -166,25 +171,51 @@ pub trait DacChannel<T: Instance, Tx> {
}
Ok(())
}
/// Write `data` to the DAC channel via DMA.
///
/// `circular` sets the DMA to circular mode.
async fn write(&mut self, data: ValueArray<'_>, circular: bool) -> Result<(), Error>
where
Tx: Dma<T>;
}
/// Hold two DAC channels
///
/// Note: This consumes the DAC `Instance` only once, allowing to get both channels simultaneously.
///
/// # Example for obtaining both DAC channels
///
/// ```no_run
/// // DMA channels and pins may need to be changed for your controller
/// let (dac_ch1, dac_ch2) =
/// embassy_stm32::dac::Dac::new(p.DAC1, p.DMA1_CH3, p.DMA1_CH4, p.PA4, p.PA5).split();
/// ```
pub struct Dac<'d, T: Instance, TxCh1, TxCh2> {
ch1: DacCh1<'d, T, TxCh1>,
ch2: DacCh2<'d, T, TxCh2>,
}
/// DAC CH1
///
/// Note: This consumes the DAC `Instance`. Use [`Dac::new`] to get both channels simultaneously.
pub struct DacCh1<'d, T: Instance, Tx> {
/// To consume T
_peri: PeripheralRef<'d, T>,
dma: PeripheralRef<'d, Tx>,
}
/// DAC CH2
///
/// Note: This consumes the DAC `Instance`. Use [`Dac::new`] to get both channels simultaneously.
pub struct DacCh2<'d, T: Instance, Tx> {
/// Instead of PeripheralRef to consume T
phantom: PhantomData<&'d mut T>,
dma: PeripheralRef<'d, Tx>,
}
impl<'d, T: Instance, Tx> DacCh1<'d, T, Tx> {
/// Perform initialisation steps for the DAC
/// Obtain DAC CH1
pub fn new(
peri: impl Peripheral<P = T> + 'd,
dma: impl Peripheral<P = Tx> + 'd,
@ -204,7 +235,8 @@ impl<'d, T: Instance, Tx> DacCh1<'d, T, Tx> {
dac
}
/// Select a new trigger for CH1 (disables the channel)
/// Select a new trigger for this channel
pub fn select_trigger(&mut self, trigger: Ch1Trigger) -> Result<(), Error> {
unwrap!(self.disable_channel());
T::regs().cr().modify(|reg| {
@ -212,91 +244,11 @@ impl<'d, T: Instance, Tx> DacCh1<'d, T, Tx> {
});
Ok(())
}
/// Write `data` to the DAC CH1 via DMA.
///
/// To prevent delays/glitches when outputting a periodic waveform, the `circular` flag can be set.
/// This will configure a circular DMA transfer that periodically outputs the `data`.
/// Note that for performance reasons in circular mode the transfer complete interrupt is disabled.
///
/// **Important:** Channel 1 has to be configured for the DAC instance!
pub async fn write(&mut self, data: ValueArray<'_>, circular: bool) -> Result<(), Error>
where
Tx: Dma<T>,
{
let channel = Channel::Ch1.index();
debug!("Writing to channel {}", channel);
// Enable DAC and DMA
T::regs().cr().modify(|w| {
w.set_en(channel, true);
w.set_dmaen(channel, true);
});
let tx_request = self.dma.request();
let dma_channel = &self.dma;
// Initiate the correct type of DMA transfer depending on what data is passed
let tx_f = match data {
ValueArray::Bit8(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr8r(channel).as_ptr() as *mut u8,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
ValueArray::Bit12Left(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr12l(channel).as_ptr() as *mut u16,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
ValueArray::Bit12Right(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr12r(channel).as_ptr() as *mut u16,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
};
tx_f.await;
// finish dma
// TODO: Do we need to check any status registers here?
T::regs().cr().modify(|w| {
// Disable the DAC peripheral
w.set_en(channel, false);
// Disable the DMA. TODO: Is this necessary?
w.set_dmaen(channel, false);
});
Ok(())
}
}
impl<'d, T: Instance, Tx> DacCh2<'d, T, Tx> {
/// Perform initialisation steps for the DAC
pub fn new_ch2(
/// Obtain DAC CH2
pub fn new(
_peri: impl Peripheral<P = T> + 'd,
dma: impl Peripheral<P = Tx> + 'd,
_pin: impl Peripheral<P = impl DacPin<T, 2>> + 'd,
@ -319,7 +271,7 @@ impl<'d, T: Instance, Tx> DacCh2<'d, T, Tx> {
dac
}
/// Select a new trigger for CH1 (disables the channel)
/// Select a new trigger for this channel
pub fn select_trigger(&mut self, trigger: Ch2Trigger) -> Result<(), Error> {
unwrap!(self.disable_channel());
T::regs().cr().modify(|reg| {
@ -327,89 +279,12 @@ impl<'d, T: Instance, Tx> DacCh2<'d, T, Tx> {
});
Ok(())
}
/// Write `data` to the DAC CH1 via DMA.
///
/// To prevent delays/glitches when outputting a periodic waveform, the `circular` flag can be set.
/// This will configure a circular DMA transfer that periodically outputs the `data`.
/// Note that for performance reasons in circular mode the transfer complete interrupt is disabled.
///
/// **Important:** Channel 1 has to be configured for the DAC instance!
pub async fn write(&mut self, data: ValueArray<'_>, circular: bool) -> Result<(), Error>
where
Tx: Dma<T>,
{
let channel = Channel::Ch2.index();
debug!("Writing to channel {}", channel);
// Enable DAC and DMA
T::regs().cr().modify(|w| {
w.set_en(channel, true);
w.set_dmaen(channel, true);
});
let tx_request = self.dma.request();
let dma_channel = &self.dma;
// Initiate the correct type of DMA transfer depending on what data is passed
let tx_f = match data {
ValueArray::Bit8(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr8r(channel).as_ptr() as *mut u8,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
ValueArray::Bit12Left(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr12l(channel).as_ptr() as *mut u16,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
ValueArray::Bit12Right(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr12r(channel).as_ptr() as *mut u16,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
};
tx_f.await;
// finish dma
// TODO: Do we need to check any status registers here?
T::regs().cr().modify(|w| {
// Disable the DAC peripheral
w.set_en(channel, false);
// Disable the DMA. TODO: Is this necessary?
w.set_dmaen(channel, false);
});
Ok(())
}
}
impl<'d, T: Instance, TxCh1, TxCh2> Dac<'d, T, TxCh1, TxCh2> {
/// Create a new DAC instance with both channels.
///
/// This is used to obtain two independent channels via `split()` for use e.g. with DMA.
pub fn new(
peri: impl Peripheral<P = T> + 'd,
dma_ch1: impl Peripheral<P = TxCh1> + 'd,
@ -447,22 +322,27 @@ impl<'d, T: Instance, TxCh1, TxCh2> Dac<'d, T, TxCh1, TxCh2> {
}
}
/// Split the DAC into CH1 and CH2 for independent use.
pub fn split(self) -> (DacCh1<'d, T, TxCh1>, DacCh2<'d, T, TxCh2>) {
(self.ch1, self.ch2)
}
/// Get mutable reference to CH1
pub fn ch1_mut(&mut self) -> &mut DacCh1<'d, T, TxCh1> {
&mut self.ch1
}
/// Get mutable reference to CH2
pub fn ch2_mut(&mut self) -> &mut DacCh2<'d, T, TxCh2> {
&mut self.ch2
}
/// Get reference to CH1
pub fn ch1(&mut self) -> &DacCh1<'d, T, TxCh1> {
&self.ch1
}
/// Get reference to CH2
pub fn ch2(&mut self) -> &DacCh2<'d, T, TxCh2> {
&self.ch2
}
@ -470,10 +350,117 @@ impl<'d, T: Instance, TxCh1, TxCh2> Dac<'d, T, TxCh1, TxCh2> {
impl<'d, T: Instance, Tx> DacChannel<T, Tx> for DacCh1<'d, T, Tx> {
const CHANNEL: Channel = Channel::Ch1;
/// Write `data` to the DAC CH1 via DMA.
///
/// To prevent delays/glitches when outputting a periodic waveform, the `circular` flag can be set.
/// This will configure a circular DMA transfer that periodically outputs the `data`.
/// Note that for performance reasons in circular mode the transfer complete interrupt is disabled.
///
/// **Important:** Channel 1 has to be configured for the DAC instance!
async fn write(&mut self, data: ValueArray<'_>, circular: bool) -> Result<(), Error>
where
Tx: Dma<T>,
{
write_inner(Self::CHANNEL, &self.dma, data, circular).await
}
}
impl<'d, T: Instance, Tx> DacChannel<T, Tx> for DacCh2<'d, T, Tx> {
const CHANNEL: Channel = Channel::Ch2;
/// Write `data` to the DAC CH2 via DMA.
///
/// To prevent delays/glitches when outputting a periodic waveform, the `circular` flag can be set.
/// This will configure a circular DMA transfer that periodically outputs the `data`.
/// Note that for performance reasons in circular mode the transfer complete interrupt is disabled.
///
/// **Important:** Channel 2 has to be configured for the DAC instance!
async fn write(&mut self, data: ValueArray<'_>, circular: bool) -> Result<(), Error>
where
Tx: Dma<T>,
{
write_inner(Self::CHANNEL, &self.dma, data, circular).await
}
}
/// Shared utility function to perform the actual DMA config and write.
async fn write_inner<T: Instance, Tx>(
ch: Channel,
dma: &PeripheralRef<'_, Tx>,
data: ValueArray<'_>,
circular: bool,
) -> Result<(), Error>
where
Tx: Dma<T>,
{
let channel = ch.index();
debug!("Writing to channel {}", channel);
// Enable DAC and DMA
T::regs().cr().modify(|w| {
w.set_en(channel, true);
w.set_dmaen(channel, true);
});
let tx_request = dma.request();
let dma_channel = dma;
// Initiate the correct type of DMA transfer depending on what data is passed
let tx_f = match data {
ValueArray::Bit8(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr8r(channel).as_ptr() as *mut u8,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
ValueArray::Bit12Left(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr12l(channel).as_ptr() as *mut u16,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
ValueArray::Bit12Right(buf) => unsafe {
Transfer::new_write(
dma_channel,
tx_request,
buf,
T::regs().dhr12r(channel).as_ptr() as *mut u16,
TransferOptions {
circular,
half_transfer_ir: false,
complete_transfer_ir: !circular,
},
)
},
};
tx_f.await;
// finish dma
// TODO: Do we need to check any status registers here?
T::regs().cr().modify(|w| {
// Disable the DAC peripheral
w.set_en(channel, false);
// Disable the DMA. TODO: Is this necessary?
w.set_dmaen(channel, false);
});
Ok(())
}
pub(crate) mod sealed {
@ -485,6 +472,7 @@ pub(crate) mod sealed {
pub trait Instance: sealed::Instance + RccPeripheral + 'static {}
dma_trait!(Dma, Instance);
/// Marks a pin that can be used with the DAC
pub trait DacPin<T: Instance, const C: u8>: crate::gpio::Pin + 'static {}
foreach_peripheral!(