Add embassy-usb-dfu

5 files changed, 39 insertions, 7 deletions

diff --git a/embassy-boot/boot/src/boot_loader.rs b/embassy-boot/boot/src/boot_loader.rs
index a8c19197b..c0deca22b 100644
--- a/embassy-boot/boot/src/boot_loader.rs
+++ b/embassy-boot/boot/src/boot_loader.rs
@@ -5,7 +5,7 @@ use embassy_sync::blocking_mutex::raw::NoopRawMutex;
 use embassy_sync::blocking_mutex::Mutex;
 use embedded_storage::nor_flash::{NorFlash, NorFlashError, NorFlashErrorKind};
 
-use crate::{State, BOOT_MAGIC, STATE_ERASE_VALUE, SWAP_MAGIC};
+use crate::{State, BOOT_MAGIC, STATE_ERASE_VALUE, SWAP_MAGIC, DFU_DETACH_MAGIC};
 
 /// Errors returned by bootloader
 #[derive(PartialEq, Eq, Debug)]
@@ -384,6 +384,8 @@ impl<ACTIVE: NorFlash, DFU: NorFlash, STATE: NorFlash> BootLoader<ACTIVE, DFU, S
 
         if !state_word.iter().any(|&b| b != SWAP_MAGIC) {
             Ok(State::Swap)
+        } else if !state_word.iter().any(|&b| b != DFU_DETACH_MAGIC) {
+            Ok(State::DfuDetach)
         } else {
             Ok(State::Boot)
         }
diff --git a/embassy-boot/boot/src/firmware_updater/asynch.rs b/embassy-boot/boot/src/firmware_updater/asynch.rs
index ae713bb6f..0a3cbc136 100644
--- a/embassy-boot/boot/src/firmware_updater/asynch.rs
+++ b/embassy-boot/boot/src/firmware_updater/asynch.rs
@@ -6,7 +6,7 @@ use embassy_sync::blocking_mutex::raw::NoopRawMutex;
 use embedded_storage_async::nor_flash::NorFlash;
 
 use super::FirmwareUpdaterConfig;
-use crate::{FirmwareUpdaterError, State, BOOT_MAGIC, STATE_ERASE_VALUE, SWAP_MAGIC};
+use crate::{FirmwareUpdaterError, State, BOOT_MAGIC, STATE_ERASE_VALUE, SWAP_MAGIC, DFU_DETACH_MAGIC};
 
 /// FirmwareUpdater is an application API for interacting with the BootLoader without the ability to
 /// 'mess up' the internal bootloader state
@@ -161,6 +161,12 @@ impl<'d, DFU: NorFlash, STATE: NorFlash> FirmwareUpdater<'d, DFU, STATE> {
         self.state.mark_updated().await
     }
 
+    /// Mark to trigger USB DFU on next boot.
+    pub async fn mark_dfu(&mut self) -> Result<(), FirmwareUpdaterError> {
+        self.state.verify_booted().await?;
+        self.state.mark_dfu().await
+    }
+
     /// Mark firmware boot successful and stop rollback on reset.
     pub async fn mark_booted(&mut self) -> Result<(), FirmwareUpdaterError> {
         self.state.mark_booted().await
@@ -247,6 +253,11 @@ impl<'d, STATE: NorFlash> FirmwareState<'d, STATE> {
         self.set_magic(SWAP_MAGIC).await
     }
 
+    /// Mark to trigger USB DFU on next boot.
+    pub async fn mark_dfu(&mut self) -> Result<(), FirmwareUpdaterError> {
+        self.set_magic(DFU_DETACH_MAGIC).await
+    }
+
     /// Mark firmware boot successful and stop rollback on reset.
     pub async fn mark_booted(&mut self) -> Result<(), FirmwareUpdaterError> {
         self.set_magic(BOOT_MAGIC).await
diff --git a/embassy-boot/boot/src/firmware_updater/blocking.rs b/embassy-boot/boot/src/firmware_updater/blocking.rs
index 76e4264a0..b2a633d1e 100644
--- a/embassy-boot/boot/src/firmware_updater/blocking.rs
+++ b/embassy-boot/boot/src/firmware_updater/blocking.rs
@@ -6,7 +6,7 @@ use embassy_sync::blocking_mutex::raw::NoopRawMutex;
 use embedded_storage::nor_flash::NorFlash;
 
 use super::FirmwareUpdaterConfig;
-use crate::{FirmwareUpdaterError, State, BOOT_MAGIC, STATE_ERASE_VALUE, SWAP_MAGIC};
+use crate::{FirmwareUpdaterError, State, BOOT_MAGIC, STATE_ERASE_VALUE, SWAP_MAGIC, DFU_DETACH_MAGIC};
 
 /// Blocking FirmwareUpdater is an application API for interacting with the BootLoader without the ability to
 /// 'mess up' the internal bootloader state
@@ -168,6 +168,12 @@ impl<'d, DFU: NorFlash, STATE: NorFlash> BlockingFirmwareUpdater<'d, DFU, STATE>
         self.state.mark_updated()
     }
 
+    /// Mark to trigger USB DFU device on next boot.
+    pub fn mark_dfu(&mut self) -> Result<(), FirmwareUpdaterError> {
+        self.state.verify_booted()?;
+        self.state.mark_dfu()
+    }
+
     /// Mark firmware boot successful and stop rollback on reset.
     pub fn mark_booted(&mut self) -> Result<(), FirmwareUpdaterError> {
         self.state.mark_booted()
@@ -226,7 +232,7 @@ impl<'d, STATE: NorFlash> BlockingFirmwareState<'d, STATE> {
 
     // Make sure we are running a booted firmware to avoid reverting to a bad state.
     fn verify_booted(&mut self) -> Result<(), FirmwareUpdaterError> {
-        if self.get_state()? == State::Boot {
+        if self.get_state()? == State::Boot || self.get_state()? == State::DfuDetach {
             Ok(())
         } else {
             Err(FirmwareUpdaterError::BadState)
@@ -243,6 +249,8 @@ impl<'d, STATE: NorFlash> BlockingFirmwareState<'d, STATE> {
 
         if !self.aligned.iter().any(|&b| b != SWAP_MAGIC) {
             Ok(State::Swap)
+        } else if !self.aligned.iter().any(|&b| b != DFU_DETACH_MAGIC) {
+            Ok(State::DfuDetach)
         } else {
             Ok(State::Boot)
         }
@@ -253,6 +261,11 @@ impl<'d, STATE: NorFlash> BlockingFirmwareState<'d, STATE> {
         self.set_magic(SWAP_MAGIC)
     }
 
+    /// Mark to trigger USB DFU on next boot.
+    pub fn mark_dfu(&mut self) -> Result<(), FirmwareUpdaterError> {
+        self.set_magic(DFU_DETACH_MAGIC)
+    }
+
     /// Mark firmware boot successful and stop rollback on reset.
     pub fn mark_booted(&mut self) -> Result<(), FirmwareUpdaterError> {
         self.set_magic(BOOT_MAGIC)
diff --git a/embassy-boot/boot/src/lib.rs b/embassy-boot/boot/src/lib.rs
index 9e70a4dca..451992945 100644
--- a/embassy-boot/boot/src/lib.rs
+++ b/embassy-boot/boot/src/lib.rs
@@ -23,6 +23,7 @@ pub use firmware_updater::{
 
 pub(crate) const BOOT_MAGIC: u8 = 0xD0;
 pub(crate) const SWAP_MAGIC: u8 = 0xF0;
+pub(crate) const DFU_DETACH_MAGIC: u8 = 0xE0;
 
 /// The state of the bootloader after running prepare.
 #[derive(PartialEq, Eq, Debug)]
@@ -32,6 +33,8 @@ pub enum State {
     Boot,
     /// Bootloader has swapped the active partition with the dfu partition and will attempt boot.
     Swap,
+    /// Application has received a DFU_DETACH request over USB, and is rebooting into the bootloader to apply a DFU.
+    DfuDetach,
 }
 
 /// Buffer aligned to 32 byte boundary, largest known alignment requirement for embassy-boot.
diff --git a/embassy-boot/stm32/src/lib.rs b/embassy-boot/stm32/src/lib.rs
index c418cb262..4b4091ac9 100644
--- a/embassy-boot/stm32/src/lib.rs
+++ b/embassy-boot/stm32/src/lib.rs
@@ -10,7 +10,10 @@ pub use embassy_boot::{
 use embedded_storage::nor_flash::NorFlash;
 
 /// A bootloader for STM32 devices.
-pub struct BootLoader;
+pub struct BootLoader {
+    /// The reported state of the bootloader after preparing for boot
+    pub state: State,
+}
 
 impl BootLoader {
     /// Inspect the bootloader state and perform actions required before booting, such as swapping firmware
@@ -19,8 +22,8 @@ impl BootLoader {
     ) -> Self {
         let mut aligned_buf = AlignedBuffer([0; BUFFER_SIZE]);
         let mut boot = embassy_boot::BootLoader::new(config);
-        boot.prepare_boot(aligned_buf.as_mut()).expect("Boot prepare error");
-        Self
+        let state = boot.prepare_boot(aligned_buf.as_mut()).expect("Boot prepare error");
+        Self { state }
     }
 
     /// Boots the application.