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Flex GPIO implementation : Input

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This commit is contained in:
amugniere@gmail.com 2022-06-30 21:41:45 +02:00
parent ffc32d3ddb
commit 9b3c5af92a
1 changed files with 105 additions and 62 deletions
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167
embassy-stm32/src/gpio.rs
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@ -7,6 +7,102 @@ use embassy_hal_common::{unborrow, unsafe_impl_unborrow};
use crate::pac::gpio::{self, vals};
use crate::{pac, peripherals, Unborrow};
/// 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, T: Pin> {
pub(crate) pin: T,
phantom: PhantomData<&'d mut T>,
}
impl<'d, T: Pin> Flex<'d, T> {
/// 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 Unborrow<Target = T> + 'd) -> Self {
unborrow!(pin);
// Pin will be in disconnected state.
Self {
pin,
phantom: PhantomData,
}
}
/// Put the pin into input mode.
#[inline]
pub fn set_as_input(&mut self, pull: Pull) {
critical_section::with(|_| unsafe {
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,
};
let crlh = if n < 8 { 0 } else { 1 };
r.cr(crlh).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.into()));
r.otyper().modify(|w| w.set_ot(n, vals::Ot::PUSHPULL));
r.moder().modify(|w| w.set_moder(n, vals::Moder::INPUT));
}
});
}
#[inline]
pub fn is_high(&self) -> bool {
!self.is_low()
}
#[inline]
pub fn is_low(&self) -> bool {
let state = unsafe { self.pin.block().idr().read().idr(self.pin.pin() as _) };
state == vals::Idr::LOW
}
}
impl<'d, T: Pin> Drop for Flex<'d, T> {
#[inline]
fn drop(&mut self) {
critical_section::with(|_| unsafe {
let r = self.pin.block();
let n = self.pin.pin() as usize;
#[cfg(gpio_v1)]
{
let crlh = if n < 8 { 0 } else { 1 };
r.cr(crlh).modify(|w| {
w.set_mode(n % 8, vals::Mode::INPUT);
w.set_cnf_in(n % 8, vals::CnfIn::FLOATING);
});
}
#[cfg(gpio_v2)]
{
r.pupdr().modify(|w| w.set_pupdr(n, vals::Pupdr::FLOATING));
r.moder().modify(|w| w.set_moder(n, vals::Moder::INPUT));
}
});
}
}
/// Pull setting for an input.
#[derive(Debug, Eq, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
@ -70,78 +166,25 @@ impl From<Speed> for vals::Ospeedr {
/// GPIO input driver.
pub struct Input<'d, T: Pin> {
pub(crate) pin: T,
phantom: PhantomData<&'d mut T>,
pub(crate) pin: Flex<'d, T>
}
impl<'d, T: Pin> Input<'d, T> {
#[inline]
pub fn new(pin: impl Unborrow<Target = T> + 'd, pull: Pull) -> Self {
unborrow!(pin);
critical_section::with(|_| unsafe {
let r = pin.block();
let n = 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,
};
let crlh = if n < 8 { 0 } else { 1 };
r.cr(crlh).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.into()));
r.otyper().modify(|w| w.set_ot(n, vals::Ot::PUSHPULL));
r.moder().modify(|w| w.set_moder(n, vals::Moder::INPUT));
}
});
Self {
pin,
phantom: PhantomData,
}
let mut pin = Flex::new(pin);
pin.set_as_input(pull);
Self { pin }
}
#[inline]
pub fn is_high(&self) -> bool {
!self.is_low()
self.pin.is_high()
}
#[inline]
pub fn is_low(&self) -> bool {
let state = unsafe { self.pin.block().idr().read().idr(self.pin.pin() as _) };
state == vals::Idr::LOW
}
}
impl<'d, T: Pin> Drop for Input<'d, T> {
#[inline]
fn drop(&mut self) {
critical_section::with(|_| unsafe {
let r = self.pin.block();
let n = self.pin.pin() as usize;
#[cfg(gpio_v1)]
{
let crlh = if n < 8 { 0 } else { 1 };
r.cr(crlh).modify(|w| w.set_cnf_in(n % 8, vals::CnfIn::FLOATING));
}
#[cfg(gpio_v2)]
r.pupdr().modify(|w| w.set_pupdr(n, vals::Pupdr::FLOATING));
});
self.pin.is_low()
}
}
@ -609,7 +652,7 @@ mod eh02 {
use super::*;
impl<'d, T: Pin> InputPin for Input<'d, T> {
impl<'d, T: Pin> InputPin for Flex<'d, T> {
type Error = Infallible;
#[inline]
@ -701,11 +744,11 @@ mod eh1 {
use super::*;
impl<'d, T: Pin> ErrorType for Input<'d, T> {
impl<'d, T: Pin> ErrorType for Flex<'d, T> {
type Error = Infallible;
}
impl<'d, T: Pin> InputPin for Input<'d, T> {
impl<'d, T: Pin> InputPin for Flex<'d, T> {
#[inline]
fn is_high(&self) -> Result<bool, Self::Error> {
Ok(self.is_high())