improve mcp23017 task

flight/src/hardware/mcp23017/mod.rs

@@ -1,96 +1,23 @@
-use crate::hardware::error::I2cError;
-use anyhow::{bail, Result};
-use embedded_hal::i2c::I2c;
-use log::{info, trace};
-use std::fmt::{Debug, Formatter};
-use std::time::Instant;
+mod pin;
+mod driver;
+mod task;
+
+use anyhow::Result;
+use embedded_hal::digital::PinState;
 
 pub trait Mcp23017 {
     fn init(&mut self) -> Result<()>;
-    fn set_pin(&mut self, pin: u8, value: bool) -> Result<()>;
-    fn flush(&mut self) -> Result<()>;
+
+    fn new_output_pin(&self, pin: u8) -> Result<impl Mcp23017OutputPin>;
+
+    fn flush(&self) -> Result<()>;
 }
 
-pub struct Mcp23017Driver<I2C> {
-    i2c: I2C,
-    address: u8,
-    bank: [u8; 2],
-    dirty: bool,
+pub trait Mcp23017OutputPin {
+    fn set_state(&mut self, pin_state: PinState);
+
+    fn set_state_on_drop(&mut self, pin_state: PinState);
 }
 
-impl<I2C> Debug for Mcp23017Driver<I2C> {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
-        write!(f, "Mcp23017Driver {{ address: {} }}", self.address)
-    }
-}
-
-impl<I2C> Mcp23017Driver<I2C>
-where
-    I2C: I2c,
-    I2C::Error: Send,
-    I2C::Error: Sync,
-    I2C::Error: 'static,
-{
-    pub fn new(i2c: I2C, address: u8) -> Self {
-        trace!("Mcp23017Driver::new(i2c, address: {address:07b})");
-        Self {
-            i2c,
-            address,
-            bank: [0u8; _],
-            dirty: false,
-        }
-    }
-}
-
-
-impl<I2C> Mcp23017 for Mcp23017Driver<I2C>
-where
-    I2C: I2c,
-    I2C::Error: Send,
-    I2C::Error: Sync,
-    I2C::Error: 'static,
-{
-    fn init(&mut self) -> Result<()> {
-        trace!("Mcp23017Driver::init(self: {self:?})");
-        // Set each pin as an output (Addresses 0x00 & 0x01)
-        let data: [u8; _] = [0x00, 0x00, 0x00];
-        self.i2c.write(self.address, &data).map_err(I2cError)?;
-
-        Ok(())
-    }
-
-    fn set_pin(&mut self, pin: u8, value: bool) -> Result<()> {
-        trace!("Mcp23017Driver::set_pin(self: {self:?}, pin: {pin}, value: {value})");
-        let (pin_bank, dirty_flag, pin_index) = match pin {
-            0..8 => {
-                (&mut self.bank[0], &mut self.dirty, pin as u32)
-            }
-            8..16 => {
-                (&mut self.bank[1], &mut self.dirty, (pin as u32) - 8)
-            }
-            _ => bail!("Invalid Pin ID"),
-        };
-        let pin_mask = 1u8.unbounded_shl(pin_index);
-        let initial = *pin_bank;
-        if value {
-            *pin_bank |= pin_mask;
-        } else {
-            *pin_bank &= !pin_mask;
-        }
-        let result = *pin_bank;
-        if initial != result {
-            *dirty_flag = true;
-        }
-        Ok(())
-    }
-
-    fn flush(&mut self) -> Result<()> {
-        trace!("Mcp23017Driver::flush(self: {self:?})");
-        if self.dirty {
-            let data: [u8; _] = [0x12, self.bank[0], self.bank[1]];
-            // This blocks while writing
-            self.i2c.write(self.address, &data).map_err(I2cError)?;
-        }
-        Ok(())
-    }
-}
+pub use driver::Mcp23017Driver;
+pub use task::Mcp23017Task;