embassy/embassy-nrf/src/gpio.rs
2021-03-29 00:58:58 +02:00

472 lines
11 KiB
Rust

use core::convert::Infallible;
use core::hint::unreachable_unchecked;
use core::marker::PhantomData;
use embassy::util::PeripheralBorrow;
use embassy_extras::unborrow;
use embedded_hal::digital::v2::{InputPin, OutputPin, StatefulOutputPin};
use gpio::pin_cnf::DRIVE_A;
use crate::pac;
use crate::pac::p0 as gpio;
use crate::peripherals;
/// A GPIO port with up to 32 pins.
#[derive(Debug, Eq, PartialEq)]
pub enum Port {
/// Port 0, available on all nRF52 and nRF51 MCUs.
Port0,
/// Port 1, only available on some nRF52 MCUs.
#[cfg(any(feature = "52833", feature = "52840"))]
Port1,
}
/// Pull setting for an input.
#[derive(Debug, Eq, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum Pull {
None,
Up,
Down,
}
/// GPIO input driver.
pub struct Input<'d, T: Pin> {
pub(crate) pin: T,
phantom: PhantomData<&'d mut T>,
}
impl<'d, T: Pin> Input<'d, T> {
pub fn new(pin: impl PeripheralBorrow<Target = T> + 'd, pull: Pull) -> Self {
unborrow!(pin);
pin.conf().write(|w| {
w.dir().input();
w.input().connect();
match pull {
Pull::None => {
w.pull().disabled();
}
Pull::Up => {
w.pull().pullup();
}
Pull::Down => {
w.pull().pulldown();
}
}
w.drive().s0s1();
w.sense().disabled();
w
});
Self {
pin,
phantom: PhantomData,
}
}
}
impl<'d, T: Pin> Drop for Input<'d, T> {
fn drop(&mut self) {
self.pin.conf().reset();
}
}
impl<'d, T: Pin> InputPin for Input<'d, T> {
type Error = Infallible;
fn is_high(&self) -> Result<bool, Self::Error> {
self.is_low().map(|v| !v)
}
fn is_low(&self) -> Result<bool, Self::Error> {
Ok(self.pin.block().in_.read().bits() & (1 << self.pin.pin()) == 0)
}
}
/// Digital input or output level.
#[derive(Debug, Eq, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
pub enum Level {
Low,
High,
}
#[derive(Clone, Copy, Debug, PartialEq)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[repr(u8)]
pub enum OutputDrive {
/// Standard '0', standard '1'
Standard = 0,
/// High drive '0', standard '1'
HighDrive0Standard1 = 1,
/// Standard '0', high drive '1'
Standard0HighDrive1 = 2,
/// High drive '0', high 'drive '1'
HighDrive = 3,
/// Disconnect '0' standard '1' (normally used for wired-or connections)
Disconnect0Standard1 = 4,
/// Disconnect '0', high drive '1' (normally used for wired-or connections)
Disconnect0HighDrive1 = 5,
/// Standard '0'. disconnect '1' (also known as "open drain", normally used for wired-and connections)
Standard0Disconnect1 = 6,
/// High drive '0', disconnect '1' (also known as "open drain", normally used for wired-and connections)
HighDrive0Disconnect1 = 7,
}
/// GPIO output driver.
pub struct Output<'d, T: Pin> {
pin: T,
phantom: PhantomData<&'d mut T>,
}
impl<'d, T: Pin> Output<'d, T> {
pub fn new(
pin: impl PeripheralBorrow<Target = T> + 'd,
initial_output: Level,
drive: OutputDrive,
) -> Self {
unborrow!(pin);
match initial_output {
Level::High => pin.set_high(),
Level::Low => pin.set_low(),
}
let drive = match drive {
OutputDrive::Standard => DRIVE_A::S0S1,
OutputDrive::HighDrive0Standard1 => DRIVE_A::H0S1,
OutputDrive::Standard0HighDrive1 => DRIVE_A::S0H1,
OutputDrive::HighDrive => DRIVE_A::H0H1,
OutputDrive::Disconnect0Standard1 => DRIVE_A::D0S1,
OutputDrive::Disconnect0HighDrive1 => DRIVE_A::D0H1,
OutputDrive::Standard0Disconnect1 => DRIVE_A::S0D1,
OutputDrive::HighDrive0Disconnect1 => DRIVE_A::H0D1,
};
pin.conf().write(|w| {
w.dir().output();
w.input().disconnect();
w.pull().disabled();
w.drive().variant(drive);
w.sense().disabled();
w
});
Self {
pin,
phantom: PhantomData,
}
}
}
impl<'d, T: Pin> Drop for Output<'d, T> {
fn drop(&mut self) {
self.pin.conf().reset();
}
}
impl<'d, T: Pin> OutputPin for Output<'d, T> {
type Error = Infallible;
/// Set the output as high.
fn set_high(&mut self) -> Result<(), Self::Error> {
unsafe {
self.pin
.block()
.outset
.write(|w| w.bits(1u32 << self.pin.pin()));
}
Ok(())
}
/// Set the output as low.
fn set_low(&mut self) -> Result<(), Self::Error> {
unsafe {
self.pin
.block()
.outclr
.write(|w| w.bits(1u32 << self.pin.pin()));
}
Ok(())
}
}
impl<'d, T: Pin> StatefulOutputPin for Output<'d, T> {
/// Is the output pin set as high?
fn is_set_high(&self) -> Result<bool, Self::Error> {
self.is_set_low().map(|v| !v)
}
/// Is the output pin set as low?
fn is_set_low(&self) -> Result<bool, Self::Error> {
Ok(self.pin.block().out.read().bits() & (1 << self.pin.pin()) == 0)
}
}
pub(crate) mod sealed {
use super::*;
pub trait Pin {
fn pin_port(&self) -> u8;
#[inline]
fn _pin(&self) -> u8 {
#[cfg(any(feature = "52833", feature = "52840"))]
{
self.pin_port() % 32
}
#[cfg(not(any(feature = "52833", feature = "52840")))]
{
self.pin_port()
}
}
#[inline]
fn block(&self) -> &gpio::RegisterBlock {
unsafe {
match self.pin_port() / 32 {
0 => &*pac::P0::ptr(),
#[cfg(any(feature = "52833", feature = "52840"))]
1 => &*pac::P1::ptr(),
_ => unreachable_unchecked(),
}
}
}
#[inline]
fn conf(&self) -> &gpio::PIN_CNF {
&self.block().pin_cnf[self._pin() as usize]
}
/// Set the output as high.
#[inline]
fn set_high(&self) {
unsafe {
self.block().outset.write(|w| w.bits(1u32 << self._pin()));
}
}
/// Set the output as low.
#[inline]
fn set_low(&self) {
unsafe {
self.block().outclr.write(|w| w.bits(1u32 << self._pin()));
}
}
}
pub trait OptionalPin {}
}
pub trait Pin: sealed::Pin + Sized {
/// Number of the pin within the port (0..31)
#[inline]
fn pin(&self) -> u8 {
self._pin()
}
/// Port of the pin
#[inline]
fn port(&self) -> Port {
match self.pin_port() / 32 {
0 => Port::Port0,
#[cfg(any(feature = "52833", feature = "52840"))]
1 => Port::Port1,
_ => unsafe { unreachable_unchecked() },
}
}
#[inline]
fn psel_bits(&self) -> u32 {
self.pin_port() as u32
}
/// Convert from concrete pin type PX_XX to type erased `AnyPin`.
#[inline]
fn degrade(self) -> AnyPin {
AnyPin {
pin_port: self.pin_port(),
}
}
}
// Type-erased GPIO pin
pub struct AnyPin {
pin_port: u8,
}
impl AnyPin {
#[inline]
pub unsafe fn steal(pin_port: u8) -> Self {
Self { pin_port }
}
}
impl Pin for AnyPin {}
impl sealed::Pin for AnyPin {
#[inline]
fn pin_port(&self) -> u8 {
self.pin_port
}
}
impl PeripheralBorrow for AnyPin {
type Target = AnyPin;
#[inline]
unsafe fn unborrow(self) -> Self::Target {
self
}
}
impl<'a> PeripheralBorrow for &'a mut AnyPin {
type Target = AnyPin;
#[inline]
unsafe fn unborrow(self) -> Self::Target {
AnyPin {
pin_port: self.pin_port,
}
}
}
// ====================
pub trait OptionalPin: sealed::OptionalPin + Sized {
type Pin: Pin;
fn pin(&self) -> Option<&Self::Pin>;
fn pin_mut(&mut self) -> Option<&mut Self::Pin>;
#[inline]
fn psel_bits(&self) -> u32 {
self.pin().map_or(1u32 << 31, |pin| Pin::psel_bits(pin))
}
/// Convert from concrete pin type PX_XX to type erased `Option<AnyPin>`.
#[inline]
fn degrade_optional(mut self) -> Option<AnyPin> {
self.pin_mut()
.map(|pin| unsafe { core::ptr::read(pin) }.degrade())
}
}
impl<T: Pin> sealed::OptionalPin for T {}
impl<T: Pin> OptionalPin for T {
type Pin = T;
#[inline]
fn pin(&self) -> Option<&T> {
Some(self)
}
#[inline]
fn pin_mut(&mut self) -> Option<&mut T> {
Some(self)
}
}
// Uninhabited enum, so it's actually impossible to create a DummyPin value.
#[doc(hidden)]
pub enum DummyPin {}
impl Pin for DummyPin {}
impl sealed::Pin for DummyPin {
#[inline]
fn pin_port(&self) -> u8 {
unreachable!()
}
}
#[derive(Clone, Copy, Debug)]
pub struct NoPin;
impl sealed::OptionalPin for NoPin {}
impl OptionalPin for NoPin {
type Pin = DummyPin;
#[inline]
fn pin(&self) -> Option<&DummyPin> {
None
}
#[inline]
fn pin_mut(&mut self) -> Option<&mut DummyPin> {
None
}
}
impl PeripheralBorrow for NoPin {
type Target = NoPin;
#[inline]
unsafe fn unborrow(self) -> Self::Target {
self
}
}
// ====================
macro_rules! make_impl {
($type:ident, $port_num:expr, $pin_num:expr) => {
impl Pin for peripherals::$type {}
impl sealed::Pin for peripherals::$type {
#[inline]
fn pin_port(&self) -> u8 {
$port_num * 32 + $pin_num
}
}
};
}
make_impl!(P0_00, 0, 0);
make_impl!(P0_01, 0, 1);
make_impl!(P0_02, 0, 2);
make_impl!(P0_03, 0, 3);
make_impl!(P0_04, 0, 4);
make_impl!(P0_05, 0, 5);
make_impl!(P0_06, 0, 6);
make_impl!(P0_07, 0, 7);
make_impl!(P0_08, 0, 8);
make_impl!(P0_09, 0, 9);
make_impl!(P0_10, 0, 10);
make_impl!(P0_11, 0, 11);
make_impl!(P0_12, 0, 12);
make_impl!(P0_13, 0, 13);
make_impl!(P0_14, 0, 14);
make_impl!(P0_15, 0, 15);
make_impl!(P0_16, 0, 16);
make_impl!(P0_17, 0, 17);
make_impl!(P0_18, 0, 18);
make_impl!(P0_19, 0, 19);
make_impl!(P0_20, 0, 20);
make_impl!(P0_21, 0, 21);
make_impl!(P0_22, 0, 22);
make_impl!(P0_23, 0, 23);
make_impl!(P0_24, 0, 24);
make_impl!(P0_25, 0, 25);
make_impl!(P0_26, 0, 26);
make_impl!(P0_27, 0, 27);
make_impl!(P0_28, 0, 28);
make_impl!(P0_29, 0, 29);
make_impl!(P0_30, 0, 30);
make_impl!(P0_31, 0, 31);
#[cfg(any(feature = "52833", feature = "52840"))]
mod _p1 {
use super::*;
make_impl!(P1_00, 1, 0);
make_impl!(P1_01, 1, 1);
make_impl!(P1_02, 1, 2);
make_impl!(P1_03, 1, 3);
make_impl!(P1_04, 1, 4);
make_impl!(P1_05, 1, 5);
make_impl!(P1_06, 1, 6);
make_impl!(P1_07, 1, 7);
make_impl!(P1_08, 1, 8);
make_impl!(P1_09, 1, 9);
make_impl!(P1_10, 1, 10);
make_impl!(P1_11, 1, 11);
make_impl!(P1_12, 1, 12);
make_impl!(P1_13, 1, 13);
make_impl!(P1_14, 1, 14);
make_impl!(P1_15, 1, 15);
}