Add Pull-Up/Pull-Down traits

Rahix · Jan 29, 2024 · 04b9250 · 04b9250
1 parent 3948972
commit 04b9250
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Showing 5 changed files with 87 additions and 1 deletion.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -6,6 +6,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 ### Added
+- Added `PortDriverPullDown` and `PortDriverPullUp` traits for port-expander ([#17]).
 - Added support for `PI4IOE5V6408` ([#17]).
 
 

diff --git a/src/common.rs b/src/common.rs
@@ -39,6 +39,16 @@ pub trait PortDriverTotemPole: PortDriver {
     fn set_direction(&mut self, mask: u32, dir: Direction, state: bool) -> Result<(), Self::Error>;
 }
 
+pub trait PortDriverPullDown: PortDriver {
+    /// Enable pull-downs for pins in mask or set the pin to floating if enable is false.
+    fn set_pull_down(&mut self, mask: u32, enable: bool) -> Result<(), Self::Error>;
+}
+
+pub trait PortDriverPullUp: PortDriver {
+    /// Enable pull-ups for pins in mask or set the pin to floating if enable is false.
+    fn set_pull_up(&mut self, mask: u32, enable: bool) -> Result<(), Self::Error>;
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum Direction {
     Input,

diff --git a/src/dev/pi4ioe5v6408.rs b/src/dev/pi4ioe5v6408.rs
@@ -204,6 +204,36 @@ impl<I2C: crate::I2cBus> crate::PortDriverTotemPole for Driver<I2C> {
     }
 }
 
+impl<I2C: crate::I2cBus> crate::PortDriverPullDown for Driver<I2C> {
+    fn set_pull_down(&mut self, mask: u32, enable: bool) -> Result<(), Self::Error> {
+        if enable {
+            self.i2c
+                .update_reg(self.addr, Regs::PullUpPullDownSelection, 0, mask as u8)?;
+            self.i2c
+                .update_reg(self.addr, Regs::PullUpPullDownEnable, mask as u8, 0)?;
+        } else {
+            self.i2c
+                .update_reg(self.addr, Regs::PullUpPullDownEnable, 0, mask as u8)?;
+        }
+        Ok(())
+    }
+}
+
+impl<I2C: crate::I2cBus> crate::PortDriverPullUp for Driver<I2C> {
+    fn set_pull_up(&mut self, mask: u32, enable: bool) -> Result<(), Self::Error> {
+        if enable {
+            self.i2c
+                .update_reg(self.addr, Regs::PullUpPullDownSelection, mask as u8, 0)?;
+            self.i2c
+                .update_reg(self.addr, Regs::PullUpPullDownEnable, mask as u8, 0)?;
+        } else {
+            self.i2c
+                .update_reg(self.addr, Regs::PullUpPullDownEnable, 0, mask as u8)?;
+        }
+        Ok(())
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::PullMode;
@@ -233,6 +263,22 @@ mod tests {
             // io0 reads
             mock_i2c::Transaction::write_read(0x43, vec![0x0f], vec![0x01]),
             mock_i2c::Transaction::write_read(0x43, vec![0x0f], vec![0x00]),
+            // io0 activate pull-up
+            mock_i2c::Transaction::write_read(0x43, vec![0x0d], vec![0b10101010]),
+            mock_i2c::Transaction::write(0x43, vec![0x0d, 0b10101011]),
+            mock_i2c::Transaction::write_read(0x43, vec![0x0b], vec![0b00001010]),
+            mock_i2c::Transaction::write(0x43, vec![0x0b, 0b00001011]),
+            // io0 disable pull-up
+            mock_i2c::Transaction::write_read(0x43, vec![0x0b], vec![0b00001011]),
+            mock_i2c::Transaction::write(0x43, vec![0x0b, 0b00001010]),
+            // io0 activate pull-down
+            mock_i2c::Transaction::write_read(0x43, vec![0x0d], vec![0b10101011]),
+            mock_i2c::Transaction::write(0x43, vec![0x0d, 0b10101010]),
+            mock_i2c::Transaction::write_read(0x43, vec![0x0b], vec![0b00001010]),
+            mock_i2c::Transaction::write(0x43, vec![0x0b, 0b00001011]),
+            // io0 disable pull-down
+            mock_i2c::Transaction::write_read(0x43, vec![0x0b], vec![0b00001011]),
+            mock_i2c::Transaction::write(0x43, vec![0x0b, 0b00001010]),
         ];
         let mut bus = mock_i2c::Mock::new(&expectations);
 
@@ -242,7 +288,7 @@ mod tests {
         let io0 = pca_pins.io0.into_output().unwrap();
         let mut io1 = pca_pins.io1.into_output_high().unwrap();
 
-        let io0 = io0.into_input().unwrap();
+        let mut io0 = io0.into_input().unwrap();
 
         io1.set_low().unwrap();
         io1.set_high().unwrap();
@@ -251,6 +297,11 @@ mod tests {
         assert!(io0.is_high().unwrap());
         assert!(io0.is_low().unwrap());
 
+        io0.enable_pull_up(true).unwrap();
+        io0.enable_pull_up(false).unwrap();
+        io0.enable_pull_down(true).unwrap();
+        io0.enable_pull_down(false).unwrap();
+
         bus.done();
     }
 

diff --git a/src/lib.rs b/src/lib.rs
@@ -73,6 +73,8 @@ pub(crate) use bus::I2cExt;
 pub(crate) use common::Direction;
 pub(crate) use common::PortDriver;
 pub(crate) use common::PortDriverPolarity;
+pub(crate) use common::PortDriverPullDown;
+pub(crate) use common::PortDriverPullUp;
 pub(crate) use common::PortDriverTotemPole;
 
 pub use dev::max7321::Max7321;

diff --git a/src/pin.rs b/src/pin.rs
@@ -119,6 +119,28 @@ where
     }
 }
 
+impl<'a, MODE: crate::mode::HasInput, MUTEX, PD> Pin<'a, MODE, MUTEX>
+where
+    PD: crate::PortDriver + crate::PortDriverPullUp,
+    MUTEX: shared_bus::BusMutex<Bus = PD>,
+{
+    pub fn enable_pull_up(&mut self, enable: bool) -> Result<(), PD::Error> {
+        self.port_driver
+            .lock(|drv| drv.set_pull_up(self.pin_mask, enable))
+    }
+}
+
+impl<'a, MODE: crate::mode::HasInput, MUTEX, PD> Pin<'a, MODE, MUTEX>
+where
+    PD: crate::PortDriver + crate::PortDriverPullDown,
+    MUTEX: shared_bus::BusMutex<Bus = PD>,
+{
+    pub fn enable_pull_down(&mut self, enable: bool) -> Result<(), PD::Error> {
+        self.port_driver
+            .lock(|drv| drv.set_pull_down(self.pin_mask, enable))
+    }
+}
+
 impl<'a, MODE: crate::mode::HasInput, MUTEX, PD> hal_digital::InputPin for Pin<'a, MODE, MUTEX>
 where
     PD: crate::PortDriver,