i2c: Add target implementation

Cargo.toml

@@ -92,3 +92,11 @@ name = "blinky"
 [[example]]
 name = "i2c"
 required-features = ["stm32h503"]
+
+[[example]]
+name = "i2c_target"
+required-features = ["stm32h503"]
+
+[[example]]
+name = "i2c_target_manual_ack"
+required-features = ["stm32h503"]

README.md

@@ -36,7 +36,7 @@ of support for peripherals is shown in the table below.
 |------------|----|---|---|
 | GPIO       | ✅ | - | |
 | ICache     | ✅ | - | |
-| I2C        | ✅ | - | Controller operation is done; Target is 🚧 |
+| I2C        | ✅ | - | |
 | CAN        | 🚧 | - | |
 | Rng        | 🚧 | [#34](https://github.com/stm32-rs/stm32h5xx-hal/issues/34)| |
 | SPI        | 🚧 | [#36](https://github.com/stm32-rs/stm32h5xx-hal/issues/36) | |

examples/i2c_target.rs

@@ -0,0 +1,65 @@
+#![deny(warnings)]
+#![no_main]
+#![no_std]
+
+#[macro_use]
+mod utilities;
+use stm32h5xx_hal::{
+    i2c::{TargetConfig, TargetListenEvent, Targetable},
+    pac,
+    prelude::*,
+};
+
+use cortex_m_rt::entry;
+
+use log::info;
+
+#[entry]
+fn main() -> ! {
+    utilities::logger::init();
+    log::set_max_level(log::LevelFilter::Debug);
+    let dp = pac::Peripherals::take().unwrap();
+
+    // Constrain and Freeze power
+    info!("Setup PWR...                  ");
+    let pwr = dp.PWR.constrain();
+    let pwrcfg = pwr.freeze();
+
+    // Constrain and Freeze clock
+    info!("Setup RCC...                  ");
+    let rcc = dp.RCC.constrain();
+    let ccdr = rcc.sys_ck(100.MHz()).freeze(pwrcfg, &dp.SBS);
+
+    let gpiob = dp.GPIOB.split(ccdr.peripheral.GPIOB);
+
+    // Configure the SCL and the SDA pin for our I2C bus
+    let scl = gpiob.pb5.into_alternate_open_drain();
+    let sda = gpiob.pb3.into_alternate_open_drain();
+
+    info!("");
+    info!("stm32h5xx-hal example - I2C Target");
+    info!("");
+
+    let own_addr: u16 = 0x18;
+    let bus_freq_hz: u32 = 100_000;
+    let mut i2c = dp.I2C2.i2c_target_only(
+        (scl, sda),
+        TargetConfig::new(own_addr, bus_freq_hz),
+        ccdr.peripheral.I2C2,
+        &ccdr.clocks,
+    );
+
+    i2c.enable_listen_event(TargetListenEvent::PrimaryAddress);
+    let mut buf = [0u8; 2];
+
+    loop {
+        let count = i2c.wait_for_target_read(&mut buf).unwrap();
+        info!("Read {count} bytes: {:X?}", &buf[..count]);
+
+        let count = i2c.wait_for_target_write(b"Hello").unwrap();
+        info!("Wrote {count} bytes");
+
+        i2c.wait_for_stop().unwrap();
+        info!("==========");
+    }
+}

examples/i2c_target_manual_ack.rs

@@ -0,0 +1,80 @@
+#![deny(warnings)]
+#![no_main]
+#![no_std]
+
+#[macro_use]
+mod utilities;
+use stm32h5xx_hal::{
+    i2c::{TargetConfig, TargetEvent, TargetListenEvent, Targetable},
+    pac,
+    prelude::*,
+};
+
+use cortex_m_rt::entry;
+
+use log::info;
+
+#[entry]
+fn main() -> ! {
+    utilities::logger::init();
+    log::set_max_level(log::LevelFilter::Info);
+    let dp = pac::Peripherals::take().unwrap();
+
+    // Constrain and Freeze power
+    info!("Setup PWR...                  ");
+    let pwr = dp.PWR.constrain();
+    let pwrcfg = pwr.freeze();
+
+    // Constrain and Freeze clock
+    info!("Setup RCC...                  ");
+    let rcc = dp.RCC.constrain();
+    let ccdr = rcc.sys_ck(100.MHz()).freeze(pwrcfg, &dp.SBS);
+
+    let gpiob = dp.GPIOB.split(ccdr.peripheral.GPIOB);
+
+    // Configure the SCL and the SDA pin for our I2C bus
+    let scl = gpiob.pb5.into_alternate_open_drain();
+    let sda = gpiob.pb3.into_alternate_open_drain();
+
+    info!("");
+    info!("stm32h5xx-hal example - I2C Target");
+    info!("");
+
+    let own_addr: u16 = 0x18;
+    let bus_freq_hz: u32 = 100_000;
+    let mut i2c = dp
+        .I2C2
+        .i2c_target_only(
+            (scl, sda),
+            TargetConfig::new(own_addr, bus_freq_hz),
+            ccdr.peripheral.I2C2,
+            &ccdr.clocks,
+        )
+        .with_manual_ack_control();
+
+    i2c.enable_listen_event(TargetListenEvent::PrimaryAddress);
+    let mut buf = [0u8; 2];
+
+    loop {
+        let event = i2c.wait_for_event().unwrap();
+        let result = match event {
+            TargetEvent::Read { address: _ } => i2c.write(b"Hello"),
+            TargetEvent::Write { address: _ } => {
+                let result = i2c.read(&mut buf);
+                // An operation can be performed here while the clock is stretched low (ie.
+                // calculating or fetching data)
+                i2c.ack_transfer();
+                result
+            }
+            TargetEvent::Stop => Ok(0),
+        };
+
+        match result {
+            Err(error) => info!("Error: {event:?} - {error:?}"),
+            Ok(count) => match event {
+                TargetEvent::Stop => info!("=========="),
+                _ => info!("{event:?} ({count})"),
+            },
+        };
+    }
+}