remove use of embedded-hal SPI traits. Instead just call our bus trait directly and push responsibility for implementing CS on the trait implementor

examples/rpi-pico-w/Cargo.toml

@@ -47,8 +47,6 @@ futures = { version = "0.3.17", default-features = false, features = [
 pio-proc = "0.2"
 pio = "0.2.1"
 
-embedded-hal-1 = { package = "embedded-hal", version = "1.0.0-alpha.9" }
-embedded-hal-async = { version = "0.2.0-alpha.0" }
 embedded-io = { version = "0.4.0", features = ["async", "defmt"] }
 heapless = "0.7.15"
 

examples/rpi-pico-w/src/main.rs

@@ -1,4 +1,4 @@
-#![no_std] 
+#![no_std]
 #![no_main]
 #![feature(type_alias_impl_trait)]
 #![feature(async_fn_in_trait)]
@@ -6,7 +6,7 @@
 
 mod pio;
 
-use core::convert::Infallible;
+use core::slice;
 use core::str::from_utf8;
 
 use defmt::*;
@@ -16,8 +16,6 @@ use embassy_net::{Config, Stack, StackResources};
 use embassy_rp::gpio::{Flex, Level, Output};
 use embassy_rp::peripherals::{DMA_CH0, PIN_23, PIN_24, PIN_25, PIN_29};
 use embassy_rp::pio::{Pio0, PioPeripherial, PioStateMachineInstance, Sm0};
-use embedded_hal_1::spi::ErrorType;
-use embedded_hal_async::spi::{ExclusiveDevice, SpiBusFlush, SpiBusRead, SpiBusWrite};
 use embedded_io::asynch::Write;
 use static_cell::StaticCell;
 use {defmt_rtt as _, panic_probe as _};
@@ -37,7 +35,7 @@ async fn wifi_task(
     runner: cyw43::Runner<
         'static,
         Output<'static, PIN_23>,
-        ExclusiveDevice<PioSpi<PioStateMachineInstance<Pio0, Sm0>, DMA_CH0>, Output<'static, PIN_25>>,
+        PioSpi<PIN_25, PioStateMachineInstance<Pio0, Sm0>, DMA_CH0>,
     >,
 ) -> ! {
     runner.run().await
@@ -75,8 +73,7 @@ async fn main(spawner: Spawner) {
 
     let (_, sm, _, _, _) = p.PIO0.split();
     let dma = p.DMA_CH0;
-    let bus = PioSpi::new(sm, p.PIN_24, p.PIN_29, dma);
-    let spi = ExclusiveDevice::new(bus, cs);
+    let spi = PioSpi::new(sm, cs, p.PIN_24, p.PIN_29, dma);
 
     let state = singleton!(cyw43::State::new());
     let (net_device, mut control, runner) = cyw43::new(state, pwr, spi, fw).await;
@@ -146,7 +143,6 @@ async fn main(spawner: Spawner) {
 
             info!("rxd {}", from_utf8(&buf[..n]).unwrap());
 
-
             match socket.write_all(&buf[..n]).await {
                 Ok(()) => {}
                 Err(e) => {
@@ -168,31 +164,13 @@ struct MySpi {
     /// - IRQ
     /// - strap to set to gSPI mode on boot.
     dio: Flex<'static, PIN_24>,
+
+    /// Chip select
+    cs: Output<'static, PIN_25>,
 }
 
-impl ErrorType for MySpi {
-    type Error = Infallible;
-}
-
-impl cyw43::SpiBusCyw43<u32> for MySpi {
-    async fn cmd_write<'a>(&'a mut self, write: &'a [u32]) -> Result<(), Self::Error> {
-        self.write(write).await
-    }
-
-    async fn cmd_read<'a>(&'a mut self, write: &'a [u32], read: &'a mut [u32]) -> Result<(), Self::Error> {
-        self.write(write).await?;
-        self.read(read).await
-    }
-}
-
-impl SpiBusFlush for MySpi {
-    async fn flush(&mut self) -> Result<(), Self::Error> {
-        Ok(())
-    }
-}
-
-impl SpiBusRead<u32> for MySpi {
-    async fn read(&mut self, words: &mut [u32]) -> Result<(), Self::Error> {
+impl MySpi {
+    async fn read(&mut self, words: &mut [u32]) {
         self.dio.set_as_input();
         for word in words {
             let mut w = 0;
@@ -210,13 +188,9 @@ impl SpiBusRead<u32> for MySpi {
             }
             *word = w
         }
-
-        Ok(())
     }
-}
 
-impl SpiBusWrite<u32> for MySpi {
-    async fn write(&mut self, words: &[u32]) -> Result<(), Self::Error> {
+    async fn write(&mut self, words: &[u32]) {
         self.dio.set_as_output();
         for word in words {
             let mut word = *word;
@@ -238,6 +212,20 @@ impl SpiBusWrite<u32> for MySpi {
         self.clk.set_low();
 
         self.dio.set_as_input();
-        Ok(())
+    }
+}
+
+impl cyw43::SpiBusCyw43 for MySpi {
+    async fn cmd_write(&mut self, write: &[u32]) {
+        self.cs.set_low();
+        self.write(write).await;
+        self.cs.set_high();
+    }
+
+    async fn cmd_read(&mut self, write: u32, read: &mut [u32]) {
+        self.cs.set_low();
+        self.write(slice::from_ref(&write)).await;
+        self.read(read).await;
+        self.cs.set_high();
     }
 }

examples/rpi-pico-w/src/pio.rs

@@ -2,34 +2,27 @@ use core::slice;
 
 use cyw43::SpiBusCyw43;
 use embassy_rp::dma::Channel;
-use embassy_rp::gpio::{Drive, Pin, Pull, SlewRate};
+use embassy_rp::gpio::{Drive, Output, Pin, Pull, SlewRate};
 use embassy_rp::pio::{PioStateMachine, ShiftDirection};
 use embassy_rp::relocate::RelocatedProgram;
 use embassy_rp::{pio_instr_util, Peripheral};
-use embedded_hal_1::spi::ErrorType;
-use embedded_hal_async::spi::SpiBusFlush;
 use pio::Wrap;
 use pio_proc::pio_asm;
 
-pub struct PioSpi<SM, DMA> {
-    // cs: Output<'static, AnyPin>,
+pub struct PioSpi<CS: Pin, SM, DMA> {
+    cs: Output<'static, CS>,
     sm: SM,
     dma: DMA,
     wrap_target: u8,
 }
 
-impl<SM, DMA> PioSpi<SM, DMA>
+impl<CS, SM, DMA> PioSpi<CS, SM, DMA>
 where
     SM: PioStateMachine,
     DMA: Channel,
+    CS: Pin,
 {
-    pub fn new<DIO, CLK>(
-        mut sm: SM,
-        // cs: AnyPin,
-        dio: DIO,
-        clk: CLK,
-        dma: DMA,
-    ) -> Self
+    pub fn new<DIO, CLK>(mut sm: SM, cs: Output<'static, CS>, dio: DIO, clk: CLK, dma: DMA) -> Self
     where
         DIO: Pin,
         CLK: Pin,
@@ -105,7 +98,7 @@ where
         pio_instr_util::set_pin(&mut sm, 0);
 
         Self {
-            // cs: Output::new(cs, Level::High),
+            cs,
             sm,
             dma,
             wrap_target: target,
@@ -156,43 +149,21 @@ where
     }
 }
 
-#[derive(Debug)]
-pub enum PioError {}
-
-impl embedded_hal_async::spi::Error for PioError {
-    fn kind(&self) -> embedded_hal_1::spi::ErrorKind {
-        embedded_hal_1::spi::ErrorKind::Other
-    }
-}
-
-impl<SM, DMA> ErrorType for PioSpi<SM, DMA>
-where
-    SM: PioStateMachine,
-{
-    type Error = PioError;
-}
-
-impl<SM, DMA> SpiBusFlush for PioSpi<SM, DMA>
-where
-    SM: PioStateMachine,
-{
-    async fn flush(&mut self) -> Result<(), Self::Error> {
-        Ok(())
-    }
-}
-
-impl<SM, DMA> SpiBusCyw43<u32> for PioSpi<SM, DMA>
+impl<CS, SM, DMA> SpiBusCyw43 for PioSpi<CS, SM, DMA>
 where
+    CS: Pin,
     SM: PioStateMachine,
     DMA: Channel,
 {
-    async fn cmd_write<'a>(&'a mut self, write: &'a [u32]) -> Result<(), Self::Error> {
+    async fn cmd_write(&mut self, write: & [u32]) {
+        self.cs.set_low();
         self.write(write).await;
-        Ok(())
+        self.cs.set_high();
     }
 
-    async fn cmd_read<'a>(&'a mut self, write: &'a [u32], read: &'a mut [u32]) -> Result<(), Self::Error> {
-        self.cmd_read(write[0], read).await;
-        Ok(())
+    async fn cmd_read(&mut self, write: u32, read: & mut [u32]) {
+        self.cs.set_low();
+        self.cmd_read(write, read).await;
+        self.cs.set_high();
     }
 }