//! General-purpose Input/Output (GPIO) #![macro_use] use core::convert::Infallible; use critical_section::CriticalSection; use embassy_hal_internal::{impl_peripheral, into_ref, PeripheralRef}; use crate::pac::gpio::{self, vals}; use crate::{pac, peripherals, Peripheral}; /// GPIO flexible pin. /// /// This pin can either be a disconnected, input, or output pin, or both. The level register bit will remain /// set while not in output mode, so the pin's level will be 'remembered' when it is not in output /// mode. pub struct Flex<'d> { pub(crate) pin: PeripheralRef<'d, AnyPin>, } impl<'d> Flex<'d> { /// Wrap the pin in a `Flex`. /// /// The pin remains disconnected. The initial output level is unspecified, but can be changed /// before the pin is put into output mode. /// #[inline] pub fn new(pin: impl Peripheral
+ 'd) -> Self { into_ref!(pin); // Pin will be in disconnected state. Self { pin: pin.map_into() } } /// Put the pin into input mode. /// /// The internal weak pull-up and pull-down resistors will be enabled according to `pull`. #[inline(never)] pub fn set_as_input(&mut self, pull: Pull) { critical_section::with(|_| { let r = self.pin.block(); let n = self.pin.pin() as usize; #[cfg(gpio_v1)] { let cnf = match pull { Pull::Up => { r.bsrr().write(|w| w.set_bs(n, true)); vals::CnfIn::PULL } Pull::Down => { r.bsrr().write(|w| w.set_br(n, true)); vals::CnfIn::PULL } Pull::None => vals::CnfIn::FLOATING, }; r.cr(n / 8).modify(|w| { w.set_mode(n % 8, vals::Mode::INPUT); w.set_cnf_in(n % 8, cnf); }); } #[cfg(gpio_v2)] { r.pupdr().modify(|w| w.set_pupdr(n, pull.to_pupdr())); r.otyper().modify(|w| w.set_ot(n, vals::Ot::PUSHPULL)); r.moder().modify(|w| w.set_moder(n, vals::Moder::INPUT)); } }); } /// Put the pin into push-pull output mode. /// /// The pin level will be whatever was set before (or low by default). If you want it to begin /// at a specific level, call `set_high`/`set_low` on the pin first. /// /// The internal weak pull-up and pull-down resistors will be disabled. #[inline(never)] pub fn set_as_output(&mut self, speed: Speed) { critical_section::with(|_| { let r = self.pin.block(); let n = self.pin.pin() as usize; #[cfg(gpio_v1)] { r.cr(n / 8).modify(|w| { w.set_mode(n % 8, speed.to_mode()); w.set_cnf_out(n % 8, vals::CnfOut::PUSHPULL); }); } #[cfg(gpio_v2)] { r.pupdr().modify(|w| w.set_pupdr(n, vals::Pupdr::FLOATING)); r.otyper().modify(|w| w.set_ot(n, vals::Ot::PUSHPULL)); r.ospeedr().modify(|w| w.set_ospeedr(n, speed.to_ospeedr())); r.moder().modify(|w| w.set_moder(n, vals::Moder::OUTPUT)); } }); } /// Put the pin into input + open-drain output mode. /// /// The hardware will drive the line low if you set it to low, and will leave it floating if you set /// it to high, in which case you can read the input to figure out whether another device /// is driving the line low. /// /// The pin level will be whatever was set before (or low by default). If you want it to begin /// at a specific level, call `set_high`/`set_low` on the pin first. /// /// The internal weak pull-up and pull-down resistors will be disabled. #[inline(never)] pub fn set_as_input_output(&mut self, speed: Speed) { #[cfg(gpio_v1)] critical_section::with(|_| { let r = self.pin.block(); let n = self.pin.pin() as usize; r.cr(n / 8).modify(|w| w.set_mode(n % 8, speed.to_mode())); r.cr(n / 8).modify(|w| w.set_cnf_out(n % 8, vals::CnfOut::OPENDRAIN)); }); #[cfg(gpio_v2)] self.set_as_input_output_pull(speed, Pull::None); } /// Put the pin into input + open-drain output mode with internal pullup or pulldown. /// /// This works like [`Self::set_as_input_output()`], but it also allows to enable the internal /// weak pull-up or pull-down resistors. #[inline(never)] #[cfg(gpio_v2)] pub fn set_as_input_output_pull(&mut self, speed: Speed, pull: Pull) { critical_section::with(|_| { let r = self.pin.block(); let n = self.pin.pin() as usize; r.pupdr().modify(|w| w.set_pupdr(n, pull.to_pupdr())); r.otyper().modify(|w| w.set_ot(n, vals::Ot::OPENDRAIN)); r.ospeedr().modify(|w| w.set_ospeedr(n, speed.to_ospeedr())); r.moder().modify(|w| w.set_moder(n, vals::Moder::OUTPUT)); }); } /// Put the pin into analog mode /// /// This mode is used by ADC and COMP but usually there is no need to set this manually /// as the mode change is handled by the driver. #[inline] pub fn set_as_analog(&mut self) { // TODO: does this also need a critical section, like other methods? self.pin.set_as_analog(); } /// Put the pin into AF mode, unchecked. /// /// This puts the pin into the AF mode, with the requested number and AF type. This is /// completely unchecked, it can attach the pin to literally any peripheral, so use with care. #[inline] pub fn set_as_af_unchecked(&mut self, af_num: u8, af_type: AfType) { critical_section::with(|_| { self.pin.set_as_af(af_num, af_type); }); } /// Get whether the pin input level is high. #[inline] pub fn is_high(&self) -> bool { !self.is_low() } /// Get whether the pin input level is low. #[inline] pub fn is_low(&self) -> bool { let state = self.pin.block().idr().read().idr(self.pin.pin() as _); state == vals::Idr::LOW } /// Get the current pin input level. #[inline] pub fn get_level(&self) -> Level { self.is_high().into() } /// Get whether the output level is set to high. #[inline] pub fn is_set_high(&self) -> bool { !self.is_set_low() } /// Get whether the output level is set to low. #[inline] pub fn is_set_low(&self) -> bool { let state = self.pin.block().odr().read().odr(self.pin.pin() as _); state == vals::Odr::LOW } /// Get the current output level. #[inline] pub fn get_output_level(&self) -> Level { self.is_set_high().into() } /// Set the output as high. #[inline] pub fn set_high(&mut self) { self.pin.set_high(); } /// Set the output as low. #[inline] pub fn set_low(&mut self) { self.pin.set_low(); } /// Set the output level. #[inline] pub fn set_level(&mut self, level: Level) { match level { Level::Low => self.pin.set_low(), Level::High => self.pin.set_high(), } } /// Toggle the output level. #[inline] pub fn toggle(&mut self) { if self.is_set_low() { self.set_high() } else { self.set_low() } } } impl<'d> Drop for Flex<'d> { #[inline] fn drop(&mut self) { critical_section::with(|_| { self.pin.set_as_disconnected(); }); } } /// Pull setting for an input. #[derive(Debug, Eq, PartialEq, Copy, Clone)] #[cfg_attr(feature = "defmt", derive(defmt::Format))] pub enum Pull { /// No pull None, /// Pull up Up, /// Pull down Down, } impl Pull { #[cfg(gpio_v2)] const fn to_pupdr(self) -> vals::Pupdr { match self { Pull::None => vals::Pupdr::FLOATING, Pull::Up => vals::Pupdr::PULLUP, Pull::Down => vals::Pupdr::PULLDOWN, } } } /// Speed setting for an output. /// /// These vary depending on the chip, check the reference manual and datasheet ("I/O port /// characteristics") for details. #[derive(Debug, Copy, Clone)] #[cfg_attr(feature = "defmt", derive(defmt::Format))] pub enum Speed { #[cfg_attr(gpio_v1, doc = "Output speed OUTPUT2MHZ")] #[cfg_attr(gpio_v2, doc = "Output speed 00")] Low, #[cfg_attr(gpio_v1, doc = "Output speed OUTPUT10MHZ")] #[cfg_attr(gpio_v2, doc = "Output speed 01")] Medium, #[cfg_attr(gpio_v2, doc = "Output speed 10")] #[cfg(not(any(gpio_v1, syscfg_f0)))] High, #[cfg_attr(gpio_v1, doc = "Output speed OUTPUT50MHZ")] #[cfg_attr(gpio_v2, doc = "Output speed 10")] VeryHigh, } impl Speed { #[cfg(gpio_v1)] const fn to_mode(self) -> vals::Mode { match self { Speed::Low => vals::Mode::OUTPUT2MHZ, Speed::Medium => vals::Mode::OUTPUT10MHZ, Speed::VeryHigh => vals::Mode::OUTPUT50MHZ, } } #[cfg(gpio_v2)] const fn to_ospeedr(self: Speed) -> vals::Ospeedr { match self { Speed::Low => vals::Ospeedr::LOWSPEED, Speed::Medium => vals::Ospeedr::MEDIUMSPEED, #[cfg(not(syscfg_f0))] Speed::High => vals::Ospeedr::HIGHSPEED, Speed::VeryHigh => vals::Ospeedr::VERYHIGHSPEED, } } } /// GPIO input driver. pub struct Input<'d> { pub(crate) pin: Flex<'d>, } impl<'d> Input<'d> { /// Create GPIO input driver for a [Pin] with the provided [Pull] configuration. #[inline] pub fn new(pin: impl Peripheral
+ 'd, pull: Pull) -> Self {
let mut pin = Flex::new(pin);
pin.set_as_input(pull);
Self { pin }
}
/// Get whether the pin input level is high.
#[inline]
pub fn is_high(&self) -> bool {
self.pin.is_high()
}
/// Get whether the pin input level is low.
#[inline]
pub fn is_low(&self) -> bool {
self.pin.is_low()
}
/// Get the current pin input level.
#[inline]
pub fn get_level(&self) -> Level {
self.pin.get_level()
}
}
/// Digital input or output level.
#[derive(Debug, Eq, PartialEq, Copy, Clone)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum Level {
/// Low
Low,
/// High
High,
}
impl From + 'd, initial_output: Level, speed: Speed) -> Self {
let mut pin = Flex::new(pin);
match initial_output {
Level::High => pin.set_high(),
Level::Low => pin.set_low(),
}
pin.set_as_output(speed);
Self { pin }
}
/// Set the output as high.
#[inline]
pub fn set_high(&mut self) {
self.pin.set_high();
}
/// Set the output as low.
#[inline]
pub fn set_low(&mut self) {
self.pin.set_low();
}
/// Set the output level.
#[inline]
pub fn set_level(&mut self, level: Level) {
self.pin.set_level(level)
}
/// Is the output pin set as high?
#[inline]
pub fn is_set_high(&self) -> bool {
self.pin.is_set_high()
}
/// Is the output pin set as low?
#[inline]
pub fn is_set_low(&self) -> bool {
self.pin.is_set_low()
}
/// What level output is set to
#[inline]
pub fn get_output_level(&self) -> Level {
self.pin.get_output_level()
}
/// Toggle pin output
#[inline]
pub fn toggle(&mut self) {
self.pin.toggle();
}
}
/// GPIO output open-drain driver.
///
/// Note that pins will **return to their floating state** when `OutputOpenDrain` is dropped.
/// If pins should retain their state indefinitely, either keep ownership of the
/// `OutputOpenDrain`, or pass it to [`core::mem::forget`].
pub struct OutputOpenDrain<'d> {
pub(crate) pin: Flex<'d>,
}
impl<'d> OutputOpenDrain<'d> {
/// Create a new GPIO open drain output driver for a [Pin] with the provided [Level] and [Speed].
#[inline]
pub fn new(pin: impl Peripheral + 'd, initial_output: Level, speed: Speed) -> Self {
let mut pin = Flex::new(pin);
match initial_output {
Level::High => pin.set_high(),
Level::Low => pin.set_low(),
}
pin.set_as_input_output(speed);
Self { pin }
}
/// Create a new GPIO open drain output driver for a [Pin] with the provided [Level], [Speed]
/// and [Pull].
#[inline]
#[cfg(gpio_v2)]
pub fn new_pull(pin: impl Peripheral + 'd, initial_output: Level, speed: Speed, pull: Pull) -> Self {
let mut pin = Flex::new(pin);
match initial_output {
Level::High => pin.set_high(),
Level::Low => pin.set_low(),
}
pin.set_as_input_output_pull(speed, pull);
Self { pin }
}
/// Get whether the pin input level is high.
#[inline]
pub fn is_high(&self) -> bool {
!self.pin.is_low()
}
/// Get whether the pin input level is low.
#[inline]
pub fn is_low(&self) -> bool {
self.pin.is_low()
}
/// Get the current pin input level.
#[inline]
pub fn get_level(&self) -> Level {
self.pin.get_level()
}
/// Set the output as high.
#[inline]
pub fn set_high(&mut self) {
self.pin.set_high();
}
/// Set the output as low.
#[inline]
pub fn set_low(&mut self) {
self.pin.set_low();
}
/// Set the output level.
#[inline]
pub fn set_level(&mut self, level: Level) {
self.pin.set_level(level);
}
/// Get whether the output level is set to high.
#[inline]
pub fn is_set_high(&self) -> bool {
self.pin.is_set_high()
}
/// Get whether the output level is set to low.
#[inline]
pub fn is_set_low(&self) -> bool {
self.pin.is_set_low()
}
/// Get the current output level.
#[inline]
pub fn get_output_level(&self) -> Level {
self.pin.get_output_level()
}
/// Toggle pin output
#[inline]
pub fn toggle(&mut self) {
self.pin.toggle()
}
}
/// GPIO output type
#[derive(Debug, Copy, Clone)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum OutputType {
/// Drive the pin both high or low.
PushPull,
/// Drive the pin low, or don't drive it at all if the output level is high.
OpenDrain,
}
impl OutputType {
#[cfg(gpio_v1)]
const fn to_cnf_out(self) -> vals::CnfOut {
match self {
OutputType::PushPull => vals::CnfOut::ALTPUSHPULL,
OutputType::OpenDrain => vals::CnfOut::ALTOPENDRAIN,
}
}
#[cfg(gpio_v2)]
const fn to_ot(self) -> vals::Ot {
match self {
OutputType::PushPull => vals::Ot::PUSHPULL,
OutputType::OpenDrain => vals::Ot::OPENDRAIN,
}
}
}
/// Alternate function type settings.
#[derive(Copy, Clone)]
#[cfg(gpio_v1)]
pub struct AfType {
mode: vals::Mode,
cnf: u8,
pull: Pull,
}
#[cfg(gpio_v1)]
impl AfType {
/// Input with optional pullup or pulldown.
pub const fn input(pull: Pull) -> Self {
let cnf_in = match pull {
Pull::Up | Pull::Down => vals::CnfIn::PULL,
Pull::None => vals::CnfIn::FLOATING,
};
Self {
mode: vals::Mode::INPUT,
cnf: cnf_in.to_bits(),
pull,
}
}
/// Output with output type and speed and no pull-up or pull-down.
pub const fn output(output_type: OutputType, speed: Speed) -> Self {
Self {
mode: speed.to_mode(),
cnf: output_type.to_cnf_out().to_bits(),
pull: Pull::None,
}
}
}
#[inline(never)]
#[cfg(gpio_v1)]
fn set_as_af(pin_port: u8, _af_num: u8, af_type: AfType) {
let pin = unsafe { AnyPin::steal(pin_port) };
let r = pin.block();
let n = pin._pin() as usize;
r.cr(n / 8).modify(|w| {
w.set_mode(n % 8, af_type.mode);
// note that we are writing the CNF field, which is exposed as both `cnf_in` and `cnf_out`
// in the PAC. the choice of `cnf_in` instead of `cnf_out` in this code is arbitrary and
// does not affect the result.
w.set_cnf_in(n % 8, vals::CnfIn::from_bits(af_type.cnf));
});
match af_type.pull {
Pull::Up => r.bsrr().write(|w| w.set_bs(n, true)),
Pull::Down => r.bsrr().write(|w| w.set_br(n, true)),
Pull::None => {}
}
}
/// Alternate function type settings.
#[derive(Copy, Clone)]
#[cfg(gpio_v2)]
pub struct AfType {
pupdr: vals::Pupdr,
ot: vals::Ot,
ospeedr: vals::Ospeedr,
}
#[cfg(gpio_v2)]
impl AfType {
/// Input with optional pullup or pulldown.
pub const fn input(pull: Pull) -> Self {
Self {
pupdr: pull.to_pupdr(),
ot: vals::Ot::PUSHPULL,
ospeedr: vals::Ospeedr::LOWSPEED,
}
}
/// Output with output type and speed and no pull-up or pull-down.
pub const fn output(output_type: OutputType, speed: Speed) -> Self {
Self::output_pull(output_type, speed, Pull::None)
}
/// Output with output type, speed and pull-up or pull-down;
pub const fn output_pull(output_type: OutputType, speed: Speed, pull: Pull) -> Self {
Self {
pupdr: pull.to_pupdr(),
ot: output_type.to_ot(),
ospeedr: speed.to_ospeedr(),
}
}
}
#[inline(never)]
#[cfg(gpio_v2)]
fn set_as_af(pin_port: u8, af_num: u8, af_type: AfType) {
let pin = unsafe { AnyPin::steal(pin_port) };
let r = pin.block();
let n = pin._pin() as usize;
r.afr(n / 8).modify(|w| w.set_afr(n % 8, af_num));
r.pupdr().modify(|w| w.set_pupdr(n, af_type.pupdr));
r.otyper().modify(|w| w.set_ot(n, af_type.ot));
r.ospeedr().modify(|w| w.set_ospeedr(n, af_type.ospeedr));
r.moder().modify(|w| w.set_moder(n, vals::Moder::ALTERNATE));
}
#[inline(never)]
fn set_as_analog(pin_port: u8) {
let pin = unsafe { AnyPin::steal(pin_port) };
let r = pin.block();
let n = pin._pin() as usize;
#[cfg(gpio_v1)]
r.cr(n / 8).modify(|w| {
w.set_mode(n % 8, vals::Mode::INPUT);
w.set_cnf_in(n % 8, vals::CnfIn::ANALOG);
});
#[cfg(gpio_v2)]
r.moder().modify(|w| w.set_moder(n, vals::Moder::ANALOG));
}
#[inline(never)]
fn get_pull(pin_port: u8) -> Pull {
let pin = unsafe { AnyPin::steal(pin_port) };
let r = pin.block();
let n = pin._pin() as usize;
#[cfg(gpio_v1)]
return match r.cr(n / 8).read().mode(n % 8) {
vals::Mode::INPUT => match r.cr(n / 8).read().cnf_in(n % 8) {
vals::CnfIn::PULL => match r.odr().read().odr(n) {
vals::Odr::LOW => Pull::Down,
vals::Odr::HIGH => Pull::Up,
},
_ => Pull::None,
},
_ => Pull::None,
};
#[cfg(gpio_v2)]
return match r.pupdr().read().pupdr(n) {
vals::Pupdr::FLOATING => Pull::None,
vals::Pupdr::PULLDOWN => Pull::Down,
vals::Pupdr::PULLUP => Pull::Up,
vals::Pupdr::_RESERVED_3 => Pull::None,
};
}
pub(crate) trait SealedPin {
fn pin_port(&self) -> u8;
#[inline]
fn _pin(&self) -> u8 {
self.pin_port() % 16
}
#[inline]
fn _port(&self) -> u8 {
self.pin_port() / 16
}
#[inline]
fn block(&self) -> gpio::Gpio {
pac::GPIO(self._port() as _)
}
/// Set the output as high.
#[inline]
fn set_high(&self) {
let n = self._pin() as _;
self.block().bsrr().write(|w| w.set_bs(n, true));
}
/// Set the output as low.
#[inline]
fn set_low(&self) {
let n = self._pin() as _;
self.block().bsrr().write(|w| w.set_br(n, true));
}
#[inline]
fn set_as_af(&self, af_num: u8, af_type: AfType) {
set_as_af(self.pin_port(), af_num, af_type)
}
#[inline]
fn set_as_analog(&self) {
set_as_analog(self.pin_port());
}
/// Set the pin as "disconnected", ie doing nothing and consuming the lowest
/// amount of power possible.
///
/// This is currently the same as [`Self::set_as_analog()`] but is semantically different
/// really. Drivers should `set_as_disconnected()` pins when dropped.
///
/// Note that this also disables the internal weak pull-up and pull-down resistors.
#[inline]
fn set_as_disconnected(&self) {
self.set_as_analog();
}
/// Get the pull-up configuration.
#[inline]
fn pull(&self) -> Pull {
critical_section::with(|_| get_pull(self.pin_port()))
}
}
/// GPIO pin trait.
#[allow(private_bounds)]
pub trait Pin: Peripheral + Into