wip: Serial audio interface (SAI)

CHANGELOG.md

@@ -13,6 +13,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
  - Enable `sdio` for stm32f446
  - port LTDC implementation and example from stm32f7xx-hal [#731]
  - IrDA mode for USARTs
+ - initial `SAI` support [#248]
  - initial `embedded-io` support [#725]
 
 ### Changed
@@ -22,6 +23,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
  - Allow different lengths of buffers in hal_1 SpiBus impl [#566]
  - `steal` UART peripheral on `Rx::new`
 
+[#248]: https://github.com/stm32-rs/stm32f4xx-hal/pull/248
 [#566]: https://github.com/stm32-rs/stm32f4xx-hal/pull/566
 [#706]: https://github.com/stm32-rs/stm32f4xx-hal/pull/706
 [#731]: https://github.com/stm32-rs/stm32f4xx-hal/pull/731

Cargo.toml

@@ -693,6 +693,10 @@ required-features = ["stm32f411", "rtic1"] # stm32f411
 name = "rtic-usb-cdc-echo"
 required-features = ["stm32f411", "rtic1", "otg-fs", "usb_fs"] # stm32f411
 
+[[example]]
+name = "sai-duplex"
+required-features = ["stm32f429"]
+
 [[example]]
 name = "sd"
 required-features = ["gpiod", "sdio", "sdio-host"] # stm32f405

examples/sai-duplex.rs

@@ -0,0 +1,89 @@
+#![deny(unsafe_code)]
+#![deny(warnings)]
+#![no_main]
+#![no_std]
+
+use panic_halt as _;
+
+use stm32f4xx_hal as hal;
+
+use crate::hal::{
+    pac,
+    prelude::*,
+    sai::{Duplex, Protocol, SlotSize, Synchronization, WordSize},
+};
+use cortex_m_rt::entry;
+
+#[entry]
+fn main() -> ! {
+    let p = pac::Peripherals::take().unwrap();
+
+    // The following code configures the both sub-blocks of SAI for full-duplex communication using
+    // I2S-encoded audio.
+
+    // Initialize clocks.
+    let rcc = p.RCC.constrain();
+    let clocks = rcc
+        .cfgr
+        .use_hse(8.MHz())
+        .saia_clk(172.MHz())
+        .saib_clk(172.MHz())
+        .freeze();
+    // Test that the SAI clock is suitable for 48000KHz audio.
+    assert!(clocks.saia_clk() == Some(172.MHz()));
+    assert!(clocks.saib_clk() == Some(172.MHz()));
+
+    let gpioe = p.GPIOE.split();
+    // SAIB is made synchronous to A.
+    let (saia, saib) = p.SAI.split_sync_b();
+    let protocol = Protocol {
+        sync: Synchronization::I2S,
+        word_size: WordSize::Bit16,
+        slot_size: SlotSize::DataSize,
+        num_slots: 2,
+    };
+    let tx = saia.master_tx(
+        (gpioe.pe2, gpioe.pe4, gpioe.pe5, gpioe.pe6),
+        protocol,
+        48.kHz(),
+        &clocks,
+    );
+    let rx = saib.slave_rx(gpioe.pe3, protocol);
+
+    let mut duplex = Duplex::new(rx, tx);
+    duplex.start();
+    loop {
+        duplex.try_send(0xaaaa, 0xf0f0).ok();
+        let _input = duplex.try_read();
+    }
+
+    /*
+    // The following code configures the A sub-block of SAI as a master transmitter for PCM-encoded audio.
+
+    // Initialize clocks.
+    let rcc = p.RCC.constrain();
+    let clocks = rcc.cfgr.use_hse(8.MHz()).saia_clk(172.MHz()).freeze();
+    // Test that the SAI clock is suitable for 48000KHz audio.
+    assert!(clocks.saia_clk() == Some(172.MHz()));
+
+    let gpioe = p.GPIOE.split();
+    let (saia, _) = p.SAI.split();
+    let protocol = Protocol {
+        sync: Synchronization::PCMShortFrame,
+        word_size: WordSize::Bit16,
+        slot_size: SlotSize::DataSize,
+        // Stereo audio, two slots per frame.
+        num_slots: 2,
+    };
+    let mut tx = saia.master_tx(
+        (gpioe.pe2, gpioe.pe4, gpioe.pe5, gpioe.pe6),
+        protocol,
+        48.kHz(),
+        &clocks,
+    );
+    tx.start();
+    loop {
+        tx.try_send(0xaaaa, 0xf0f0).ok();
+    }
+    */
+}

src/dma/traits.rs

@@ -355,12 +355,7 @@ pub struct FLT<T, const F: u8> {
 impl<T, const F: u8> crate::Sealed for FLT<T, F> {}
 
 #[cfg(feature = "sai")]
-pub struct SAICH<T, const C: u8> {
-    _per: PhantomData<T>,
-}
-
-#[cfg(feature = "sai")]
-impl<T, const C: u8> crate::Sealed for SAICH<T, C> {}
+pub use crate::sai::SAICH;
 
 dma_map!(
     (Stream0<DMA2>:0, MemoryToMemory<u8>, [MemoryToMemory<u8> | MemoryToMemory<u16> | MemoryToMemory<u32>]),

src/dma/traits/f4.rs

@@ -475,38 +475,19 @@ mod sai1 {
     use pac::SAI1;
 
     dma_map!(
-        (Stream1<DMA2>:0, SAICH<SAI1, 0>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_A
-        (Stream3<DMA2>:0, SAICH<SAI1, 0>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_A
-        (Stream4<DMA2>:1, SAICH<SAI1, 1>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_B
-        (Stream5<DMA2>:0, SAICH<SAI1, 1>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_B:DMA_CHANNEL_0
+        (Stream1<DMA2>:0, SAICH<SAI1, false>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_A
+        (Stream3<DMA2>:0, SAICH<SAI1, false>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_A
+        (Stream4<DMA2>:1, SAICH<SAI1, true>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_B
+        (Stream5<DMA2>:0, SAICH<SAI1, true>, [MemoryToPeripheral | PeripheralToMemory]), //SAI1_B:DMA_CHANNEL_0
     );
-
-    unsafe impl<const C: u8> PeriAddress for SAICH<SAI1, C> {
-        #[inline(always)]
-        fn address(&self) -> u32 {
-            unsafe { (*SAI1::ptr()).ch(C as usize).dr().as_ptr() as u32 }
-        }
-
-        type MemSize = u32;
-    }
 }
 #[cfg(feature = "sai2")]
 dma_map!(
-    (Stream4<DMA2>:3, SAICH<pac::SAI2, 0>, [MemoryToPeripheral | PeripheralToMemory]), //SAI2_A
-    (Stream6<DMA2>:3, SAICH<pac::SAI2, 1>, [MemoryToPeripheral | PeripheralToMemory]), //SAI2_B
-    (Stream7<DMA2>:0, SAICH<pac::SAI2, 1>, [MemoryToPeripheral | PeripheralToMemory]), //SAI2_B:DMA_CHANNEL_0
+    (Stream4<DMA2>:3, SAICH<pac::SAI2, false>, [MemoryToPeripheral | PeripheralToMemory]), //SAI2_A
+    (Stream6<DMA2>:3, SAICH<pac::SAI2, true>, [MemoryToPeripheral | PeripheralToMemory]), //SAI2_B
+    (Stream7<DMA2>:0, SAICH<pac::SAI2, true>, [MemoryToPeripheral | PeripheralToMemory]), //SAI2_B:DMA_CHANNEL_0
 );
 
-#[cfg(feature = "sai2")]
-unsafe impl<const C: u8> PeriAddress for SAICH<pac::SAI2, C> {
-    #[inline(always)]
-    fn address(&self) -> u32 {
-        unsafe { (*pac::SAI2::ptr()).ch(C as usize).dr().as_ptr() as u32 }
-    }
-
-    type MemSize = u32;
-}
-
 #[cfg(feature = "spi6")]
 dma_map!(
     (Stream5<DMA2>:1, pac::SPI6, [MemoryToPeripheral]), //SPI6_TX

src/gpio/alt/f4.rs

@@ -2502,7 +2502,7 @@ pub mod sai1 {
             PF9<7>,
         ],
 
-        <MclkA, PushPull> for [
+        <MclkA, PushPull> for no:NoPin, [
             #[cfg(feature = "gpio-f413")]
             PA15<10>,
 
@@ -2516,7 +2516,7 @@ pub mod sai1 {
             PG7<6>,
         ],
 
-        <MclkB, PushPull> for [
+        <MclkB, PushPull> for no:NoPin, [
             #[cfg(feature = "gpio-f446")]
             PC0<6>,
 
@@ -2611,19 +2611,18 @@ pub mod sai1 {
     use crate::pac::SAI;
     #[cfg(any(feature = "stm32f427", feature = "stm32f437", feature = "gpio-f446"))]
     use crate::pac::SAI1 as SAI;
-    pub struct ChannelA;
-    pub struct ChannelB;
+    pub use crate::sai::{SAI1A, SAI1B};
     impl SaiChannels for SAI {
-        type A = ChannelA;
-        type B = ChannelB;
+        type A = SAI1A;
+        type B = SAI1B;
     }
-    impl SaiChannel for ChannelA {
+    impl SaiChannel for SAI1A {
         type Fs = FsA;
         type Mclk = MclkA;
         type Sck = SckA;
         type Sd = SdA;
     }
-    impl SaiChannel for ChannelB {
+    impl SaiChannel for SAI1B {
         type Fs = FsB;
         type Mclk = MclkB;
         type Sck = SckB;
@@ -2686,19 +2685,18 @@ pub mod sai2 {
     }
 
     use crate::pac::SAI2 as SAI;
-    pub struct ChannelA;
-    pub struct ChannelB;
+    pub use crate::sai::{SAI2A, SAI2B};
     impl SaiChannels for SAI {
-        type A = ChannelA;
-        type B = ChannelB;
+        type A = SAI2A;
+        type B = SAI2B;
     }
-    impl SaiChannel for ChannelA {
+    impl SaiChannel for SAI2A {
         type Fs = FsA;
         type Mclk = MclkA;
         type Sck = SckA;
         type Sd = SdA;
     }
-    impl SaiChannel for ChannelB {
+    impl SaiChannel for SAI2B {
         type Fs = FsB;
         type Mclk = MclkB;
         type Sck = SckB;

src/lib.rs

@@ -117,6 +117,8 @@ pub mod qei;
 pub mod qspi;
 pub mod rcc;
 pub mod rtc;
+#[cfg(feature = "sai")]
+pub mod sai;
 #[cfg(all(feature = "sdio-host", feature = "sdio"))]
 pub mod sdio;
 pub mod serial;

src/prelude.rs

@@ -68,6 +68,8 @@ pub use crate::qei::QeiExt as _stm32f4xx_hal_QeiExt;
 pub use crate::rcc::RccExt as _stm32f4xx_hal_rcc_RccExt;
 #[cfg(feature = "rng")]
 pub use crate::rng::RngExt as _stm32f4xx_hal_rng_RngExt;
+#[cfg(feature = "sai")]
+pub use crate::sai::SAIExt as _;
 pub use crate::serial::dma::SerialHandleIT as _stm32f4xx_hal_serial_dma_SerialHandleIT;
 pub use crate::serial::dma::SerialReadDMA as _stm32f4xx_hal_serial_dma_SerialReadDMA;
 pub use crate::serial::dma::SerialWriteDMA as _stm32f4xx_hal_serial_dma_SerialWriteDMA;

src/rcc/f4/enable.rs

@@ -276,7 +276,12 @@ bus_lpenable!(ADC3 => 10);
 #[cfg(feature = "adc3")]
 bus_reset!(ADC3 => 8);
 
-#[cfg(feature = "stm32f413")]
+#[cfg(any(
+    feature = "gpio-f413",
+    feature = "gpio-f469",
+    feature = "stm32f429",
+    feature = "stm32f439"
+))]
 bus! {
     SAI => (APB2, 22),
 }