create input_capture

1 files changed, 141 insertions, 0 deletions

diff --git a/embassy-stm32/src/timer/input_capture.rs b/embassy-stm32/src/timer/input_capture.rs
new file mode 100644
index 000000000..6401656c8
--- /dev/null
+++ b/embassy-stm32/src/timer/input_capture.rs
@@ -0,0 +1,141 @@
+//! Input capture driver.
+
+use core::marker::PhantomData;
+
+use embassy_hal_internal::{into_ref, PeripheralRef};
+use embassy_sync::channel;
+
+use super::low_level::{CountingMode, InputCaptureMode, InputTISelection, Timer};
+use super::{Channel, Channel1Pin, Channel2Pin, Channel3Pin, Channel4Pin, GeneralInstance4Channel};
+use crate::gpio::{AFType, AnyPin, Pull};
+use crate::time::Hertz;
+use crate::Peripheral;
+
+/// Channel 1 marker type.
+pub enum Ch1 {}
+/// Channel 2 marker type.
+pub enum Ch2 {}
+/// Channel 3 marker type.
+pub enum Ch3 {}
+/// Channel 4 marker type.
+pub enum Ch4 {}
+
+/// Capture pin wrapper.
+///
+/// This wraps a pin to make it usable with capture.
+pub struct CapturePin<'d, T, C> {
+    _pin: PeripheralRef<'d, AnyPin>,
+    phantom: PhantomData<(T, C)>,
+}
+
+macro_rules! channel_impl {
+    ($new_chx:ident, $channel:ident, $pin_trait:ident) => {
+        impl<'d, T: GeneralInstance4Channel> CapturePin<'d, T, $channel> {
+            #[doc = concat!("Create a new ", stringify!($channel), " capture pin instance.")]
+            pub fn $new_chx(pin: impl Peripheral<P = impl $pin_trait<T>> + 'd, pull_type: Pull) -> Self {
+                into_ref!(pin);
+                critical_section::with(|_| {
+                    pin.set_as_af_pull(pin.af_num(), AFType::Input, pull_type);
+                    #[cfg(gpio_v2)]
+                    pin.set_speed(crate::gpio::Speed::VeryHigh);
+                });
+                CapturePin {
+                    _pin: pin.map_into(),
+                    phantom: PhantomData,
+                }
+            }
+        }
+    };
+}
+
+channel_impl!(new_ch1, Ch1, Channel1Pin);
+channel_impl!(new_ch2, Ch2, Channel2Pin);
+channel_impl!(new_ch3, Ch3, Channel3Pin);
+channel_impl!(new_ch4, Ch4, Channel4Pin);
+
+/// Input capture driver.
+pub struct InputCapture<'d, T: GeneralInstance4Channel> {
+    inner: Timer<'d, T>,
+}
+
+impl<'d, T: GeneralInstance4Channel> InputCapture<'d, T> {
+    /// Create a new input capture driver.
+    pub fn new(
+        tim: impl Peripheral<P = T> + 'd,
+        _ch1: Option<CapturePin<'d, T, Ch1>>,
+        _ch2: Option<CapturePin<'d, T, Ch2>>,
+        _ch3: Option<CapturePin<'d, T, Ch3>>,
+        _ch4: Option<CapturePin<'d, T, Ch4>>,
+        freq: Hertz,
+        counting_mode: CountingMode,
+    ) -> Self {
+        Self::new_inner(tim, freq, counting_mode)
+    }
+
+    fn new_inner(tim: impl Peripheral<P = T> + 'd, freq: Hertz, counting_mode: CountingMode) -> Self {
+        let mut this = Self { inner: Timer::new(tim) };
+
+        this.inner.set_counting_mode(counting_mode);
+        this.set_tick_freq(freq);
+        this.inner.enable_outputs(); // Required for advanced timers, see GeneralInstance4Channel for details
+        this.inner.start();
+
+        [Channel::Ch1, Channel::Ch2, Channel::Ch3, Channel::Ch4]
+            .iter()
+            .for_each(|&channel| {
+                this.inner.set_input_capture_mode(channel, InputCaptureMode::Rising);
+
+                this.inner.set_input_ti_selection(channel, InputTISelection::Normal);
+            });
+
+        this
+    }
+
+    /// Enable the given channel.
+    pub fn enable(&mut self, channel: Channel) {
+        self.inner.enable_channel(channel, true);
+    }
+
+    /// Disable the given channel.
+    pub fn disable(&mut self, channel: Channel) {
+        self.inner.enable_channel(channel, false);
+    }
+
+    /// Check whether given channel is enabled
+    pub fn is_enabled(&self, channel: Channel) -> bool {
+        self.inner.get_channel_enable_state(channel)
+    }
+
+    /// Set tick frequency.
+    ///
+    /// Note: when you call this, the max period value changes
+    pub fn set_tick_freq(&mut self, freq: Hertz) {
+        let f = freq;
+        assert!(f.0 > 0);
+        let timer_f = self.inner.get_clock_frequency();
+
+        let pclk_ticks_per_timer_period = timer_f / f;
+        let psc: u16 = unwrap!((pclk_ticks_per_timer_period - 1).try_into());
+
+        let regs = self.inner.regs_core();
+        regs.psc().write_value(psc);
+
+        // Generate an Update Request
+        regs.egr().write(|r| r.set_ug(true));
+    }
+
+    /// Set the input capture mode for a given channel.
+    pub fn set_input_capture_mode(&mut self, channel: Channel, mode: InputCaptureMode) {
+        self.inner.set_input_capture_mode(channel, mode);
+    }
+
+    /// Set input TI selection.
+    pub fn set_input_ti_selection(&mut self, channel: Channel, tisel: InputTISelection) {
+        self.inner.set_input_ti_selection(channel, tisel)
+    }
+
+    /// Get capture value for a channel.
+    pub fn get_capture_value(&self, channel: Channel) -> u32 {
+        self.inner.get_capture_value(channel)
+    }
+}