Add initializers for peripherals based on numbers

src/adc.rs

@@ -6,13 +6,25 @@ impl ADCLine {
     /// Initialize an ADC line and get it as a handle. This is declared as unsafe as it may only
     /// be called once. (A safe abstraction would need to check which RIOT devices have been
     /// initialized already).
+    ///
+    /// This being unsafe is inconsistent with other subsystem wrappers that chose to not declare
+    /// this unsafe; that inconsistency is tracked in
+    /// <https://github.com/RIOT-OS/rust-riot-wrappers/issues/59> and so far unresolved.
     pub unsafe fn init(line: riot_sys::adc_t) -> Result<Self, i32> {
         let success = riot_sys::adc_init(line);
         match success {
             0 => Ok(ADCLine(line)),
             e => Err(e),
         }
     }
+
+    /// Initialize an ADC line identified by the line number it is assigned on the board
+    ///
+    /// Safety: See [init]
+    pub unsafe fn from_number(line: u32) -> Result<Self, i32> {
+        let line = riot_sys::macro_ADC_LINE(line);
+        Self::init(line)
+    }
 }
 
 /// A configured representation of the single operating-system level ADC that RIOT exposes via its

src/gpio.rs

@@ -85,14 +85,16 @@ impl GPIO {
         }
     }
 
-    // using a generic GPIO_PIN is probably best done by making GPIO_INIT a static inline (given
-    // it's already fixed to types at tests/periph_gpio/main.c)
-    //     /// Create a GPIO out of thin air
-    //     #[cfg(riot_module_nrf5x_common_periph)]
-    //     pub unsafe fn new(port: u8, pin: u8) -> Self {
-    //         // EXPANDED cpu/nrf5x_common/include/periph_cpu_common.h:50
-    //         GPIO(((port << 5) | pin).into())
-    //     }
+    /// Create a GPIO from its port and pin numbers
+    ///
+    /// ```
+    /// let pin_c8 = GPIO::from_port_and_pin(3, 8);
+    /// ```
+    ///
+    /// See [from_c] for safety constraints.
+    pub fn from_port_and_pin(port: u32, pin: u32) -> Option<Self> {
+        Self::from_c(unsafe { riot_sys::macro_GPIO_PIN(port, pin) })
+    }
 
     pub fn configure_as_output(
         self,

src/spi.rs

@@ -10,7 +10,7 @@ use riot_sys::{
     spi_transfer_bytes,
 };
 
-pub struct SPIDevice(pub spi_t);
+pub struct SPIDevice(#[deprecated(note = "Use constructor instead")] pub spi_t);
 
 pub struct AcquiredSPI<'a> {
     device: &'a mut SPIDevice,
@@ -24,6 +24,17 @@ impl<'a> Drop for AcquiredSPI<'a> {
 }
 
 impl SPIDevice {
+    /// Create an SPI device from an `spi_t`
+    pub fn from_c(bus: spi_t) -> Self {
+        Self(bus)
+    }
+
+    /// Create an SPI device from the number it is assigned on the board
+    pub fn from_number(bus: u32) -> Self {
+        let bus = unsafe { riot_sys::macro_SPI_DEV(bus) };
+        Self::from_c(bus)
+    }
+
     pub fn acquire<'a>(
         &'a mut self,
         cs: spi_cs_t,

tests/gpio/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "riot-wrappers-test-gpio"
+version = "0.1.0"
+authors = ["Christian Amsüss <chrysn@fsfe.org>"]
+edition = "2021"
+publish = false
+
+[lib]
+crate-type = ["staticlib"]
+
+[profile.release]
+panic = "abort"
+
+[dependencies]
+riot-wrappers = { version = "*", features = [ "set_panic_handler", "panic_handler_format" ] }
+riot-sys = "*"
+embedded-hal = "0.2.4"

tests/gpio/Makefile

@@ -0,0 +1,8 @@
+# name of your application
+APPLICATION = riot-wrappers-test-gpio
+APPLICATION_RUST_MODULE = riot_wrappers_test_gpio
+BASELIBS += $(APPLICATION_RUST_MODULE).module
+FEATURES_REQUIRED += rust_target
+FEATURES_REQUIRED += periph_gpio
+
+include $(RIOTBASE)/Makefile.include

tests/gpio/src/lib.rs

@@ -0,0 +1,35 @@
+#![no_std]
+
+use riot_wrappers::gpio::{InputMode, OutputMode, GPIO};
+use riot_wrappers::println;
+use riot_wrappers::riot_main;
+
+use embedded_hal::digital::v2::{InputPin, OutputPin, PinState};
+
+riot_main!(main);
+
+fn main() {
+    let (out_port, out_pin, in_port, in_pin, in_mode) = match riot_wrappers::BOARD {
+        // Won't work -- currently, native GPIO don't do anything (but let's not panic already)
+        "native" => (0, 0, 0, 1, InputMode::In),
+        // 0.17 is LED1, 0.13 is button 1
+        "nrf52dk" => (0, 17, 0, 13, InputMode::InPullUp),
+
+        // Better safe than drive pins that were not supposed to be driven
+        _ => panic!("For this board, no GPIO pins were deemed safe to reconfigure."),
+    };
+    let mut p_out = GPIO::from_port_and_pin(out_port, out_pin)
+        .expect("Out pin does not exist")
+        .configure_as_output(OutputMode::Out)
+        .expect("Out pin could not be configured");
+    let p_in = GPIO::from_port_and_pin(in_port, in_pin)
+        .expect("In pin does not exist")
+        .configure_as_input(in_mode)
+        .expect("In pin could not be configured");
+
+    loop {
+        let value = p_in.is_high().unwrap();
+        println!("Read GPIO value {}, writing it to the out port", value);
+        p_out.set_state(if value { PinState::High } else { PinState::Low });
+    }
+}