From 4d0e3838168a7447b3580135ef78d65baa578933 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Timo=20Kro=CC=88ger?= <timokroeger93@gmail.com>
Date: Thu, 7 Mar 2024 11:17:39 +0100
Subject: [PATCH] [UCPD] Prepare for PD communication implementation

---
 embassy-stm32/src/ucpd.rs            | 47 +++++++++++++++++++++++++++-
 examples/stm32g4/src/bin/usb_c_pd.rs | 15 ++++++++-
 2 files changed, 60 insertions(+), 2 deletions(-)

diff --git a/embassy-stm32/src/ucpd.rs b/embassy-stm32/src/ucpd.rs
index a366fadda..96cd92764 100644
--- a/embassy-stm32/src/ucpd.rs
+++ b/embassy-stm32/src/ucpd.rs
@@ -22,9 +22,10 @@ use embassy_hal_internal::drop::OnDrop;
 use embassy_hal_internal::{into_ref, Peripheral, PeripheralRef};
 use embassy_sync::waitqueue::AtomicWaker;
 
+use crate::dma::AnyChannel;
 use crate::interrupt;
-pub use crate::pac::ucpd::vals::TypecVstateCc as CcVState;
 use crate::pac::ucpd::vals::{Anamode, Ccenable, PscUsbpdclk};
+pub use crate::pac::ucpd::vals::{Phyccsel as CcSel, TypecVstateCc as CcVState};
 use crate::rcc::RccPeripheral;
 
 /// Pull-up or Pull-down resistor state of both CC lines.
@@ -177,6 +178,50 @@ impl<'d, T: Instance> Ucpd<'d, T> {
             })
         });
     }
+
+    /// Returns PD receiver and transmitter.
+    pub fn pd(
+        &mut self,
+        rx_dma: impl Peripheral<P = impl RxDma<T>> + 'd,
+        tx_dma: impl Peripheral<P = impl TxDma<T>> + 'd,
+        cc_sel: CcSel,
+    ) -> (PdRx<'_, T>, PdTx<'_, T>) {
+        into_ref!(rx_dma, tx_dma);
+        let rx_dma_req = rx_dma.request();
+        let tx_dma_req = tx_dma.request();
+        (
+            PdRx {
+                _ucpd: self,
+                dma_ch: rx_dma.map_into(),
+                dma_req: rx_dma_req,
+            },
+            PdTx {
+                _ucpd: self,
+                dma_ch: tx_dma.map_into(),
+                dma_req: tx_dma_req,
+            },
+        )
+    }
+}
+
+/// Power Delivery (PD) Receiver.
+pub struct PdRx<'d, T: Instance> {
+    _ucpd: &'d Ucpd<'d, T>,
+    dma_ch: PeripheralRef<'d, AnyChannel>,
+    dma_req: Request,
+}
+
+impl<'d, T: Instance> Drop for PdRx<'d, T> {
+    fn drop(&mut self) {
+        T::REGS.cr().modify(|w| w.set_phyrxen(false));
+    }
+}
+
+/// Power Delivery (PD) Transmitter.
+pub struct PdTx<'d, T: Instance> {
+    _ucpd: &'d Ucpd<'d, T>,
+    dma_ch: PeripheralRef<'d, AnyChannel>,
+    dma_req: Request,
 }
 
 /// Interrupt handler.
diff --git a/examples/stm32g4/src/bin/usb_c_pd.rs b/examples/stm32g4/src/bin/usb_c_pd.rs
index 7a0065087..1443cb773 100644
--- a/examples/stm32g4/src/bin/usb_c_pd.rs
+++ b/examples/stm32g4/src/bin/usb_c_pd.rs
@@ -3,7 +3,7 @@
 
 use defmt::{info, Format};
 use embassy_executor::Spawner;
-use embassy_stm32::ucpd::{self, CcPull, CcVState, Ucpd};
+use embassy_stm32::ucpd::{self, CcPull, CcSel, CcVState, Ucpd};
 use embassy_stm32::Config;
 use embassy_time::{with_timeout, Duration};
 use {defmt_rtt as _, panic_probe as _};
@@ -56,5 +56,18 @@ async fn main(_spawner: Spawner) {
     let cable_orientation = wait_attached(&mut ucpd).await;
     info!("USB cable connected, orientation: {}", cable_orientation);
 
+    let cc_sel = match cable_orientation {
+        CableOrientation::Normal => {
+            info!("Starting PD communication on CC1 pin");
+            CcSel::CC1
+        }
+        CableOrientation::Flipped => {
+            info!("Starting PD communication on CC2 pin");
+            CcSel::CC2
+        }
+        CableOrientation::DebugAccessoryMode => panic!("No PD communication in DAM"),
+    };
+    let (mut _rx, mut _tx) = ucpd.pd(p.DMA1_CH1, p.DMA1_CH2, cc_sel);
+
     loop {}
 }