embassy/embassy-rp/src/pwm.rs
2023-04-23 22:49:15 +02:00

339 lines
8.9 KiB
Rust

//! Pulse Width Modulation (PWM)
use embassy_embedded_hal::SetConfig;
use embassy_hal_common::{into_ref, Peripheral, PeripheralRef};
use fixed::traits::ToFixed;
use fixed::FixedU16;
use pac::pwm::regs::{ChDiv, Intr};
use pac::pwm::vals::Divmode;
use crate::gpio::sealed::Pin as _;
use crate::gpio::{AnyPin, Pin as GpioPin};
use crate::{pac, peripherals, RegExt};
#[non_exhaustive]
#[derive(Clone)]
pub struct Config {
pub invert_a: bool,
pub invert_b: bool,
pub phase_correct: bool,
pub enable: bool,
pub divider: fixed::FixedU16<fixed::types::extra::U4>,
pub compare_a: u16,
pub compare_b: u16,
pub top: u16,
}
impl Default for Config {
fn default() -> Self {
Self {
invert_a: false,
invert_b: false,
phase_correct: false,
enable: true, // differs from reset value
divider: 1.to_fixed(),
compare_a: 0,
compare_b: 0,
top: 0xffff,
}
}
}
pub enum InputMode {
Level,
RisingEdge,
FallingEdge,
}
impl From<InputMode> for Divmode {
fn from(value: InputMode) -> Self {
match value {
InputMode::Level => Divmode::LEVEL,
InputMode::RisingEdge => Divmode::RISE,
InputMode::FallingEdge => Divmode::FALL,
}
}
}
pub struct Pwm<'d, T: Channel> {
inner: PeripheralRef<'d, T>,
pin_a: Option<PeripheralRef<'d, AnyPin>>,
pin_b: Option<PeripheralRef<'d, AnyPin>>,
}
impl<'d, T: Channel> Pwm<'d, T> {
fn new_inner(
inner: impl Peripheral<P = T> + 'd,
a: Option<PeripheralRef<'d, AnyPin>>,
b: Option<PeripheralRef<'d, AnyPin>>,
config: Config,
divmode: Divmode,
) -> Self {
into_ref!(inner);
let p = inner.regs();
unsafe {
p.csr().modify(|w| {
w.set_divmode(divmode);
w.set_en(false);
});
p.ctr().write(|w| w.0 = 0);
Self::configure(p, &config);
if let Some(pin) = &a {
pin.io().ctrl().write(|w| w.set_funcsel(4));
}
if let Some(pin) = &b {
pin.io().ctrl().write(|w| w.set_funcsel(4));
}
}
Self {
inner,
pin_a: a.into(),
pin_b: b.into(),
}
}
#[inline]
pub fn new_free(inner: impl Peripheral<P = T> + 'd, config: Config) -> Self {
Self::new_inner(inner, None, None, config, Divmode::DIV)
}
#[inline]
pub fn new_output_a(
inner: impl Peripheral<P = T> + 'd,
a: impl Peripheral<P = impl PwmPinA<T>> + 'd,
config: Config,
) -> Self {
into_ref!(a);
Self::new_inner(inner, Some(a.map_into()), None, config, Divmode::DIV)
}
#[inline]
pub fn new_output_b(
inner: impl Peripheral<P = T> + 'd,
b: impl Peripheral<P = impl PwmPinB<T>> + 'd,
config: Config,
) -> Self {
into_ref!(b);
Self::new_inner(inner, None, Some(b.map_into()), config, Divmode::DIV)
}
#[inline]
pub fn new_output_ab(
inner: impl Peripheral<P = T> + 'd,
a: impl Peripheral<P = impl PwmPinA<T>> + 'd,
b: impl Peripheral<P = impl PwmPinB<T>> + 'd,
config: Config,
) -> Self {
into_ref!(a, b);
Self::new_inner(inner, Some(a.map_into()), Some(b.map_into()), config, Divmode::DIV)
}
#[inline]
pub fn new_input(
inner: impl Peripheral<P = T> + 'd,
b: impl Peripheral<P = impl PwmPinB<T>> + 'd,
mode: InputMode,
config: Config,
) -> Self {
into_ref!(b);
Self::new_inner(inner, None, Some(b.map_into()), config, mode.into())
}
#[inline]
pub fn new_output_input(
inner: impl Peripheral<P = T> + 'd,
a: impl Peripheral<P = impl PwmPinA<T>> + 'd,
b: impl Peripheral<P = impl PwmPinB<T>> + 'd,
mode: InputMode,
config: Config,
) -> Self {
into_ref!(a, b);
Self::new_inner(inner, Some(a.map_into()), Some(b.map_into()), config, mode.into())
}
fn configure(p: pac::pwm::Channel, config: &Config) {
if config.divider > FixedU16::<fixed::types::extra::U4>::from_bits(0xFF_F) {
panic!("Requested divider is too large");
}
unsafe {
p.div().write_value(ChDiv(config.divider.to_bits() as u32));
p.cc().write(|w| {
w.set_a(config.compare_a);
w.set_b(config.compare_b);
});
p.top().write(|w| w.set_top(config.top));
p.csr().modify(|w| {
w.set_a_inv(config.invert_a);
w.set_b_inv(config.invert_b);
w.set_ph_correct(config.phase_correct);
w.set_en(config.enable);
});
}
}
#[inline]
pub unsafe fn phase_advance(&mut self) {
let p = self.inner.regs();
p.csr().write_set(|w| w.set_ph_adv(true));
while p.csr().read().ph_adv() {}
}
#[inline]
pub unsafe fn phase_retard(&mut self) {
let p = self.inner.regs();
p.csr().write_set(|w| w.set_ph_ret(true));
while p.csr().read().ph_ret() {}
}
#[inline]
pub fn counter(&self) -> u16 {
unsafe { self.inner.regs().ctr().read().ctr() }
}
#[inline]
pub fn set_counter(&self, ctr: u16) {
unsafe { self.inner.regs().ctr().write(|w| w.set_ctr(ctr)) }
}
#[inline]
pub fn wait_for_wrap(&mut self) {
while !self.wrapped() {}
self.clear_wrapped();
}
#[inline]
pub fn wrapped(&mut self) -> bool {
unsafe { pac::PWM.intr().read().0 & self.bit() != 0 }
}
#[inline]
pub fn clear_wrapped(&mut self) {
unsafe {
pac::PWM.intr().write_value(Intr(self.bit() as _));
}
}
#[inline]
fn bit(&self) -> u32 {
1 << self.inner.number() as usize
}
}
pub struct PwmBatch(u32);
impl PwmBatch {
#[inline]
pub fn enable(&mut self, pwm: &Pwm<'_, impl Channel>) {
self.0 |= pwm.bit();
}
#[inline]
pub fn set_enabled(enabled: bool, batch: impl FnOnce(&mut PwmBatch)) {
let mut en = PwmBatch(0);
batch(&mut en);
unsafe {
if enabled {
pac::PWM.en().write_set(|w| w.0 = en.0);
} else {
pac::PWM.en().write_clear(|w| w.0 = en.0);
}
}
}
}
impl<'d, T: Channel> Drop for Pwm<'d, T> {
fn drop(&mut self) {
unsafe {
self.inner.regs().csr().write_clear(|w| w.set_en(false));
if let Some(pin) = &self.pin_a {
pin.io().ctrl().write(|w| w.set_funcsel(31));
}
if let Some(pin) = &self.pin_b {
pin.io().ctrl().write(|w| w.set_funcsel(31));
}
}
}
}
mod sealed {
pub trait Channel {}
}
pub trait Channel: Peripheral<P = Self> + sealed::Channel + Sized + 'static {
fn number(&self) -> u8;
fn regs(&self) -> pac::pwm::Channel {
pac::PWM.ch(self.number() as _)
}
}
macro_rules! channel {
($name:ident, $num:expr) => {
impl sealed::Channel for peripherals::$name {}
impl Channel for peripherals::$name {
fn number(&self) -> u8 {
$num
}
}
};
}
channel!(PWM_CH0, 0);
channel!(PWM_CH1, 1);
channel!(PWM_CH2, 2);
channel!(PWM_CH3, 3);
channel!(PWM_CH4, 4);
channel!(PWM_CH5, 5);
channel!(PWM_CH6, 6);
channel!(PWM_CH7, 7);
pub trait PwmPinA<T: Channel>: GpioPin {}
pub trait PwmPinB<T: Channel>: GpioPin {}
macro_rules! impl_pin {
($pin:ident, $channel:ident, $kind:ident) => {
impl $kind<peripherals::$channel> for peripherals::$pin {}
};
}
impl_pin!(PIN_0, PWM_CH0, PwmPinA);
impl_pin!(PIN_1, PWM_CH0, PwmPinB);
impl_pin!(PIN_2, PWM_CH1, PwmPinA);
impl_pin!(PIN_3, PWM_CH1, PwmPinB);
impl_pin!(PIN_4, PWM_CH2, PwmPinA);
impl_pin!(PIN_5, PWM_CH2, PwmPinB);
impl_pin!(PIN_6, PWM_CH3, PwmPinA);
impl_pin!(PIN_7, PWM_CH3, PwmPinB);
impl_pin!(PIN_8, PWM_CH4, PwmPinA);
impl_pin!(PIN_9, PWM_CH4, PwmPinB);
impl_pin!(PIN_10, PWM_CH5, PwmPinA);
impl_pin!(PIN_11, PWM_CH5, PwmPinB);
impl_pin!(PIN_12, PWM_CH6, PwmPinA);
impl_pin!(PIN_13, PWM_CH6, PwmPinB);
impl_pin!(PIN_14, PWM_CH7, PwmPinA);
impl_pin!(PIN_15, PWM_CH7, PwmPinB);
impl_pin!(PIN_16, PWM_CH0, PwmPinA);
impl_pin!(PIN_17, PWM_CH0, PwmPinB);
impl_pin!(PIN_18, PWM_CH1, PwmPinA);
impl_pin!(PIN_19, PWM_CH1, PwmPinB);
impl_pin!(PIN_20, PWM_CH2, PwmPinA);
impl_pin!(PIN_21, PWM_CH2, PwmPinB);
impl_pin!(PIN_22, PWM_CH3, PwmPinA);
impl_pin!(PIN_23, PWM_CH3, PwmPinB);
impl_pin!(PIN_24, PWM_CH4, PwmPinA);
impl_pin!(PIN_25, PWM_CH4, PwmPinB);
impl_pin!(PIN_26, PWM_CH5, PwmPinA);
impl_pin!(PIN_27, PWM_CH5, PwmPinB);
impl_pin!(PIN_28, PWM_CH6, PwmPinA);
impl_pin!(PIN_29, PWM_CH6, PwmPinB);
impl<'d, T: Channel> SetConfig for Pwm<'d, T> {
type Config = Config;
fn set_config(&mut self, config: &Self::Config) {
Self::configure(self.inner.regs(), config);
}
}