rp: add PWM api

tests/rp/src/bin/pwm.rs

@@ -0,0 +1,142 @@
+#![no_std]
+#![no_main]
+#![feature(type_alias_impl_trait)]
+
+use defmt::{assert, assert_eq, assert_ne, *};
+use embassy_executor::Spawner;
+use embassy_rp::gpio::{Input, Level, Output, Pull};
+use embassy_rp::pwm::{Config, InputMode, Pwm};
+use embassy_time::{Duration, Timer};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let mut p = embassy_rp::init(Default::default());
+    info!("Hello World!");
+
+    // Connections on CI device: 6 -> 9, 7 -> 11
+    let (mut p6, mut p7, mut p9, mut p11) = (p.PIN_6, p.PIN_7, p.PIN_9, p.PIN_11);
+
+    let cfg = {
+        let mut c = Config::default();
+        c.divider = 125.into();
+        c.top = 10000;
+        c.compare_a = 5000;
+        c.compare_b = 5000;
+        c
+    };
+
+    // Test free-running clock
+    {
+        let pwm = Pwm::new_free(&mut p.PWM_CH3, cfg.clone());
+        cortex_m::asm::delay(125);
+        let ctr = pwm.counter();
+        assert!(ctr > 0);
+        assert!(ctr < 100);
+        cortex_m::asm::delay(125);
+        assert!(ctr < pwm.counter());
+    }
+
+    for invert_a in [false, true] {
+        info!("free-running, invert A: {}", invert_a);
+        let mut cfg = cfg.clone();
+        cfg.invert_a = invert_a;
+        cfg.invert_b = !invert_a;
+
+        // Test output from A
+        {
+            let pin1 = Input::new(&mut p9, Pull::None);
+            let _pwm = Pwm::new_output_a(&mut p.PWM_CH3, &mut p6, cfg.clone());
+            Timer::after(Duration::from_millis(1)).await;
+            assert_eq!(pin1.is_low(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_eq!(pin1.is_high(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_eq!(pin1.is_low(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_eq!(pin1.is_high(), invert_a);
+        }
+
+        // Test output from B
+        {
+            let pin2 = Input::new(&mut p11, Pull::None);
+            let _pwm = Pwm::new_output_b(&mut p.PWM_CH3, &mut p7, cfg.clone());
+            Timer::after(Duration::from_millis(1)).await;
+            assert_ne!(pin2.is_low(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_ne!(pin2.is_high(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_ne!(pin2.is_low(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_ne!(pin2.is_high(), invert_a);
+        }
+
+        // Test output from A+B
+        {
+            let pin1 = Input::new(&mut p9, Pull::None);
+            let pin2 = Input::new(&mut p11, Pull::None);
+            let _pwm = Pwm::new_output_ab(&mut p.PWM_CH3, &mut p6, &mut p7, cfg.clone());
+            Timer::after(Duration::from_millis(1)).await;
+            assert_eq!(pin1.is_low(), invert_a);
+            assert_ne!(pin2.is_low(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_eq!(pin1.is_high(), invert_a);
+            assert_ne!(pin2.is_high(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_eq!(pin1.is_low(), invert_a);
+            assert_ne!(pin2.is_low(), invert_a);
+            Timer::after(Duration::from_millis(5)).await;
+            assert_eq!(pin1.is_high(), invert_a);
+            assert_ne!(pin2.is_high(), invert_a);
+        }
+    }
+
+    // Test level-gated
+    {
+        let mut pin2 = Output::new(&mut p11, Level::Low);
+        let pwm = Pwm::new_input(&mut p.PWM_CH3, &mut p7, InputMode::Level, cfg.clone());
+        assert_eq!(pwm.counter(), 0);
+        Timer::after(Duration::from_millis(5)).await;
+        assert_eq!(pwm.counter(), 0);
+        pin2.set_high();
+        Timer::after(Duration::from_millis(1)).await;
+        pin2.set_low();
+        let ctr = pwm.counter();
+        assert!(ctr >= 1000);
+        Timer::after(Duration::from_millis(1)).await;
+        assert_eq!(pwm.counter(), ctr);
+    }
+
+    // Test rising-gated
+    {
+        let mut pin2 = Output::new(&mut p11, Level::Low);
+        let pwm = Pwm::new_input(&mut p.PWM_CH3, &mut p7, InputMode::RisingEdge, cfg.clone());
+        assert_eq!(pwm.counter(), 0);
+        Timer::after(Duration::from_millis(5)).await;
+        assert_eq!(pwm.counter(), 0);
+        pin2.set_high();
+        Timer::after(Duration::from_millis(1)).await;
+        pin2.set_low();
+        assert_eq!(pwm.counter(), 1);
+        Timer::after(Duration::from_millis(1)).await;
+        assert_eq!(pwm.counter(), 1);
+    }
+
+    // Test falling-gated
+    {
+        let mut pin2 = Output::new(&mut p11, Level::High);
+        let pwm = Pwm::new_input(&mut p.PWM_CH3, &mut p7, InputMode::FallingEdge, cfg.clone());
+        assert_eq!(pwm.counter(), 0);
+        Timer::after(Duration::from_millis(5)).await;
+        assert_eq!(pwm.counter(), 0);
+        pin2.set_low();
+        Timer::after(Duration::from_millis(1)).await;
+        pin2.set_high();
+        assert_eq!(pwm.counter(), 1);
+        Timer::after(Duration::from_millis(1)).await;
+        assert_eq!(pwm.counter(), 1);
+    }
+
+    info!("Test OK");
+    cortex_m::asm::bkpt();
+}