Add support for the PI4IOE5V6408

README.md

@@ -43,6 +43,7 @@ a similar existing implementation as inspiration.  Contributions welcome!
 - [`PCF8574`](https://docs.rs/port-expander/latest/port_expander/dev/pcf8574/struct.Pcf8574.html)
 - [`PCF8575`](https://docs.rs/port-expander/latest/port_expander/dev/pcf8575/struct.Pcf8575.html)
 - [`TCA6408A`](https://docs.rs/port-expander/latest/port_expander/dev/tca6408a/struct.Tca6408a.html)
+- [`PI4IOE5V6408`](https://docs.rs/port-expander/latest/port_expander/dev/pi4ioe5v6408/struct.Pi4ioe5v6408.html)
 
 ## Non-local sharing
 `port-expander` uses the `BusMutex` from

src/dev/mod.rs

@@ -11,4 +11,5 @@ pub mod pcal6408a;
 pub mod pcal6416a;
 pub mod pcf8574;
 pub mod pcf8575;
+pub mod pi4ioe5v6408;
 pub mod tca6408a;

src/dev/pi4ioe5v6408.rs

@@ -0,0 +1,282 @@
+//! Support for the `PI4IOE5V6408` "Low-voltage Translating 8-bit I2C-bus I/O Expander"
+use crate::I2cExt;
+
+/// `PI4IOE5V6408` "Low-voltage Translating 8-bit I2C-bus I/O Expander"
+pub struct Pi4ioe5v6408<M>(M);
+
+impl<I2C> Pi4ioe5v6408<shared_bus::NullMutex<Driver<I2C>>>
+where
+    I2C: crate::I2cBus,
+{
+    /// Create a new driver for the `PI4IOE5V6408` "Low-voltage Translating 8-bit I2C-bus I/O Expander"
+    /// All pins will be configured as floating inputs
+    ///
+    /// # Arguments
+    /// - `i2c` - The I2C bus the device is connected to
+    /// - `addr` - The address of the device. The address is 0x43 if `addr` is `false` and 0x44 if `addr` is `true`
+    pub fn new(i2c: I2C, addr: bool) -> Result<Self, I2C::BusError> {
+        Self::with_mutex(i2c, addr)
+    }
+}
+
+impl<I2C, M> Pi4ioe5v6408<M>
+where
+    I2C: crate::I2cBus,
+    M: shared_bus::BusMutex<Bus = Driver<I2C>>,
+{
+    /// Create a new driver for the `PI4IOE5V6408` "Low-voltage Translating 8-bit I2C-bus I/O Expander"
+    /// with a mutex.
+    /// All pins will be configured as floating inputs
+    ///
+    /// # Arguments
+    /// - `i2c` - The I2C bus the device is connected to
+    /// - `addr` - The address of the device. The address is 0x43 if `addr` is `false` and 0x44 if `addr` is `true`
+    pub fn with_mutex(i2c: I2C, addr: bool) -> Result<Self, I2C::BusError> {
+        Ok(Self(shared_bus::BusMutex::create(Driver::new(
+            i2c, addr, false,
+        )?)))
+    }
+
+    /// Create a new driver for the `PI4IOE5V6408` "Low-voltage Translating 8-bit I2C-bus I/O Expander"
+    /// retaining the previous (pullup/down and interrupt) configuration.
+    ///
+    /// Warning: Only use this constructor to recreate the driver for a chip that has been properly initialized before.
+    ///
+    /// # Arguments
+    /// - `i2c` - The I2C bus the device is connected to
+    /// - `addr` - The address of the device. The address is 0x43 if `addr` is `false` and 0x44 if `addr` is `true`
+    pub fn with_retained_pin_config(i2c: I2C, addr: bool) -> Result<Self, I2C::BusError> {
+        Ok(Self(shared_bus::BusMutex::create(Driver::new(
+            i2c, addr, true,
+        )?)))
+    }
+
+    pub fn split<'a>(&'a mut self) -> Parts<'a, I2C, M> {
+        Parts {
+            io0: crate::Pin::new(0, &self.0),
+            io1: crate::Pin::new(1, &self.0),
+            io2: crate::Pin::new(2, &self.0),
+            io3: crate::Pin::new(3, &self.0),
+            io4: crate::Pin::new(4, &self.0),
+            io5: crate::Pin::new(5, &self.0),
+            io6: crate::Pin::new(6, &self.0),
+            io7: crate::Pin::new(7, &self.0),
+        }
+    }
+}
+
+pub struct Parts<'a, I2C, M = shared_bus::NullMutex<Driver<I2C>>>
+where
+    I2C: crate::I2cBus,
+    M: shared_bus::BusMutex<Bus = Driver<I2C>>,
+{
+    pub io0: crate::Pin<'a, crate::mode::Input, M>,
+    pub io1: crate::Pin<'a, crate::mode::Input, M>,
+    pub io2: crate::Pin<'a, crate::mode::Input, M>,
+    pub io3: crate::Pin<'a, crate::mode::Input, M>,
+    pub io4: crate::Pin<'a, crate::mode::Input, M>,
+    pub io5: crate::Pin<'a, crate::mode::Input, M>,
+    pub io6: crate::Pin<'a, crate::mode::Input, M>,
+    pub io7: crate::Pin<'a, crate::mode::Input, M>,
+}
+
+#[allow(dead_code)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum Regs {
+    DeviceIdControl = 0x01,
+    IODirection = 0x03,
+    OutputPort = 0x05,
+    OutputHighImpedance = 0x07,
+    InputDefaultState = 0x09,
+    PullUpPullDownEnable = 0x0b,
+    PullUpPullDownSelection = 0x0d,
+    InputStatusRegister = 0x0f,
+    InterruptMaskRegister = 0x11,
+    InterruptStatusRegister = 0x13,
+}
+
+impl From<Regs> for u8 {
+    fn from(r: Regs) -> u8 {
+        r as u8
+    }
+}
+
+pub struct Driver<I2C> {
+    i2c: I2C,
+    addr: u8,
+    out: u8,
+}
+
+impl<I2C: crate::I2cBus> Driver<I2C> {
+    pub fn new(mut i2c: I2C, addr: bool, retain_config: bool) -> Result<Self, I2C::BusError> {
+        let addr = if addr { 0x44 } else { 0x43 };
+
+        let device_id = i2c.read_reg(addr, Regs::DeviceIdControl)?; // Reset the "(Power on) Reset Interrupt" bit (and validate the device ID)
+        assert_eq!(
+            device_id & 0xFC, // Only check Manufacturer ID (0b101) and Firmware Revision (0b000)
+            0xA0,
+            "Unexpected Device ID for the PI4IOE5V6408: 0x{:02x}",
+            device_id
+        );
+
+        // The Reset values are the following:
+
+        // i2c.write_reg(addr, Regs::IODirection, 0)?; // All pins as inputs
+        // i2c.write_reg(addr, Regs::OutputPort, 0)?; // Set all outputs to low
+        // i2c.write_reg(addr, Regs::OutputHighImpedance, 0xff)?; // Set high impedance mode on all outputs
+        // i2c.write_reg(addr, Regs::InputDefaultState, 0)?; // The default state of all inputs is 0
+        // i2c.write_reg(addr, Regs::PullUpPullDownEnable, 0xff)?; // Pull-Up/Pull-Down enabled on all inputs
+        // i2c.write_reg(addr, Regs::PullUpPullDownSelection, 0)?; // Pull-Downs on all inputs
+        // i2c.write_reg(addr, Regs::InterruptMaskRegister, 0)?; // Interrupts enabled on all inputs
+
+        let mut out = 0;
+
+        if retain_config {
+            out = i2c.read_reg(addr, Regs::OutputPort)?; // Read the current output state once
+        } else {
+            // First time this driver is initialized, after it has been reset: Change reset values we don't want
+            i2c.write_reg(addr, Regs::OutputHighImpedance, 0)?; // Disable high impedance mode on all outputs
+            i2c.write_reg(addr, Regs::InterruptMaskRegister, 0xff)?; // Disable interrupts on all inputs
+            i2c.write_reg(addr, Regs::PullUpPullDownEnable, 0)?; // Disable pull-up/pull-down on all inputs
+        }
+
+        Ok(Self { i2c, addr, out })
+    }
+}
+
+impl<I2C: crate::I2cBus> crate::PortDriver for Driver<I2C> {
+    type Error = I2C::BusError;
+
+    fn set(&mut self, mask_high: u32, mask_low: u32) -> Result<(), Self::Error> {
+        let previous = self.out;
+        self.out |= mask_high as u8;
+        self.out &= !mask_low as u8;
+        if self.out != previous {
+            self.i2c.write_reg(self.addr, Regs::OutputPort, self.out)
+        } else {
+            // don't do the transfer when nothing changed
+            Ok(())
+        }
+    }
+
+    fn is_set(&mut self, mask_high: u32, mask_low: u32) -> Result<u32, Self::Error> {
+        Ok(((self.out as u32) & mask_high) | (!(self.out as u32) & mask_low))
+    }
+
+    fn get(&mut self, mask_high: u32, mask_low: u32) -> Result<u32, Self::Error> {
+        let in_ = self.i2c.read_reg(self.addr, Regs::InputStatusRegister)? as u32;
+        Ok((in_ & mask_high) | (!in_ & mask_low))
+    }
+}
+
+impl<I2C: crate::I2cBus> crate::PortDriverTotemPole for Driver<I2C> {
+    fn set_direction(
+        &mut self,
+        mask: u32,
+        dir: crate::Direction,
+        state: bool,
+    ) -> Result<(), Self::Error> {
+        // set state before switching direction to prevent glitch
+        if dir == crate::Direction::Output {
+            use crate::PortDriver;
+            if state {
+                self.set(mask, 0)?;
+            } else {
+                self.set(0, mask)?;
+            }
+        }
+
+        let (mask_set, mask_clear) = match dir {
+            crate::Direction::Output => (mask as u8, 0), // Outputs are set to 1
+            crate::Direction::Input => (0, mask as u8),  // Inputs are set to 0
+        };
+        self.i2c
+            .update_reg(self.addr, Regs::IODirection, mask_set, mask_clear)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use embedded_hal_mock::eh1::i2c as mock_i2c;
+    use shared_bus::NullMutex;
+
+    #[test]
+    fn pi4ioe5v6408() {
+        let expectations = [
+            // driver setup
+            mock_i2c::Transaction::write_read(0x43, vec![0x01], vec![0xa2]),
+            mock_i2c::Transaction::write(0x43, vec![0x07, 0b00000000]),
+            mock_i2c::Transaction::write(0x43, vec![0x11, 0b11111111]),
+            mock_i2c::Transaction::write(0x43, vec![0x0b, 0b00000000]),
+            // pin setup io0
+            mock_i2c::Transaction::write_read(0x43, vec![0x03], vec![0]),
+            mock_i2c::Transaction::write(0x43, vec![0x03, 0b00000001]),
+            // pin setup io1
+            mock_i2c::Transaction::write(0x43, vec![0x05, 0b00000010]),
+            mock_i2c::Transaction::write_read(0x43, vec![0x03], vec![0b00000001]),
+            mock_i2c::Transaction::write(0x43, vec![0x03, 0b00000011]),
+            // pin setup io0 as input
+            mock_i2c::Transaction::write_read(0x43, vec![0x03], vec![0b00000011]),
+            mock_i2c::Transaction::write(0x43, vec![0x03, 0b00000010]),
+            // io1 writes
+            mock_i2c::Transaction::write(0x43, vec![0x05, 0b00000000]),
+            mock_i2c::Transaction::write(0x43, vec![0x05, 0b00000010]),
+            mock_i2c::Transaction::write(0x43, vec![0x05, 0b00000000]),
+            // io0 reads
+            mock_i2c::Transaction::write_read(0x43, vec![0x0f], vec![0b00000001]),
+            mock_i2c::Transaction::write_read(0x43, vec![0x0f], vec![0b00000000]),
+        ];
+        let mut bus = mock_i2c::Mock::new(&expectations);
+
+        let mut pca = super::Pi4ioe5v6408::new(bus.clone(), false).unwrap();
+        let pca_pins = pca.split();
+
+        let io0 = pca_pins.io0.into_output().unwrap();
+        let mut io1 = pca_pins.io1.into_output_high().unwrap();
+
+        let io0 = io0.into_input().unwrap();
+
+        io1.set_low().unwrap();
+        io1.set_high().unwrap();
+        io1.toggle().unwrap();
+
+        assert!(io0.is_high().unwrap());
+        assert!(io0.is_low().unwrap());
+
+        bus.done();
+    }
+
+    #[test]
+    fn pi4ioe5v6408_retained() {
+        let expectations = [
+            // driver setup
+            mock_i2c::Transaction::write_read(0x44, vec![0x01], vec![0xa2]),
+            mock_i2c::Transaction::write_read(0x44, vec![0x05], vec![0b10101111]),
+            // pin setup io0
+            mock_i2c::Transaction::write(0x44, vec![0x05, 0b10101110]),
+            mock_i2c::Transaction::write_read(0x44, vec![0x03], vec![0]),
+            mock_i2c::Transaction::write(0x44, vec![0x03, 0b00000001]),
+            // pin setup io1
+            mock_i2c::Transaction::write_read(0x44, vec![0x03], vec![0b00000001]),
+            mock_i2c::Transaction::write(0x44, vec![0x03, 0b00000011]),
+            // io1 writes
+            mock_i2c::Transaction::write(0x44, vec![0x05, 0b10101100]),
+            mock_i2c::Transaction::write(0x44, vec![0x05, 0b10101110]),
+            mock_i2c::Transaction::write(0x44, vec![0x05, 0b10101100]),
+        ];
+        let mut bus = mock_i2c::Mock::new(&expectations);
+
+        let mut pca: super::Pi4ioe5v6408<NullMutex<_>> =
+            super::Pi4ioe5v6408::with_retained_pin_config(bus.clone(), true).unwrap();
+        let pca_pins = pca.split();
+
+        let _io0 = pca_pins.io0.into_output().unwrap();
+        let mut io1 = pca_pins.io1.into_output_high().unwrap();
+
+        io1.set_low().unwrap();
+        io1.set_high().unwrap();
+        io1.toggle().unwrap();
+
+        bus.done();
+    }
+}