Support power off request by board during init

openemc-bootloader/src/board.rs

@@ -4,7 +4,7 @@ use core::num::NonZeroU32;
 
 use openemc_shared::{BootInfo, ResetStatus};
 
-use crate::{i2c_reg_slave::I2CRegTransaction, BoardInitResult};
+use crate::{i2c_reg_slave::I2CRegTransaction, util::enter_standby, BoardInitResult};
 
 /// Board-specific functionality.
 pub trait Board {
@@ -65,4 +65,9 @@ pub trait Board {
     fn timeout_ticks(&mut self) -> Option<NonZeroU32> {
         Some(defmt::unwrap!(NonZeroU32::new(4_200_000_000)))
     }
+
+    /// Shutdown the system and go to sleep.
+    fn power_off(&mut self) -> ! {
+        enter_standby();
+    }
 }

openemc-bootloader/src/main.rs

@@ -128,6 +128,8 @@ pub enum BoardInitResult {
     StartBootloader,
     /// Perform factory reset.
     FactoryReset,
+    /// Power off the board.
+    PowerOff,
 }
 
 use boards::Chosen as ThisBoard;
@@ -163,7 +165,7 @@ fn main() -> ! {
     backup::write(BACKUP_REG_BOOT_REASON, BootReason::SurpriseInBootloader as _);
 
     // Start watchdog.
-    if boot_reason != BootReason::PowerOff as _ {
+    if boot_reason != BootReason::PowerOff as _ && boot_reason == BootReason::PowerOffBootloader as _ {
         watchdog::start();
     }
 
@@ -196,12 +198,29 @@ fn main() -> ! {
     );
     defmt::info!("");
 
+    // Check for shutdown request.
+    if boot_reason == BootReason::PowerOffBootloader as _ {
+        defmt::info!("power off in bootloader");
+        backup::write(BACKUP_REG_BOOT_REASON, BootReason::PowerOn as _);
+        board.power_off();
+    }
+
     // Initialize board.
     defmt::info!("board init");
     watchdog::pet();
     let board_init = board.init(boot_reason, reset_status);
     defmt::info!("board init result: {:?}", board_init);
 
+    // Shutdown if requested by board.
+    if board_init == BoardInitResult::PowerOff {
+        defmt::info!("power off requested by board");
+        backup::write(BACKUP_REG_BOOT_REASON, BootReason::PowerOffBootloader as _);
+        backup::disable();
+
+        delay_ms(10);
+        SCB::sys_reset();
+    }
+
     // Perform factory reset if requested by board.
     if board_init == BoardInitResult::FactoryReset {
         defmt::info!("factory reset");

openemc-firmware/src/main.rs

@@ -148,6 +148,8 @@ pub enum PowerMode {
     Full,
     /// Power only components required for charging.
     Charging,
+    /// Shutdown.
+    Off,
 }
 
 /// I2C register slave that may have remapped pins.
@@ -364,7 +366,7 @@ mod app {
             || bi.boot_reason == BootReason::Restart as _
         {
             // Make sure system is powered off for at least one second.
-            defmt::info!("Board off delay");
+            defmt::info!("board off delay");
             delay.delay(1u32.secs());
         }
         if bi.boot_reason == BootReason::PowerOff as _ {
@@ -390,7 +392,14 @@ mod app {
         defmt::info!("RTC ready:      {}", rtc.is_ready());
         unwrap!(print_rtc_info::spawn());
 
-        // Initializes board.
+        // Power off if requested.
+        if power_mode == PowerMode::Off {
+            defmt::info!("power off requested by board");
+            delay.delay(10u32.millis());
+            boot::power_off(&mut bkp);
+        }
+
+        // Power on board.
         defmt::info!("board power on in mode {:?}", power_mode);
         board.set_power_led(power_mode == PowerMode::Full);
         board.power_on(&mut delay);
@@ -499,6 +508,7 @@ mod app {
                 Some(slave)
             }
             PowerMode::Charging => None,
+            PowerMode::Off => None,
         };
 
         // Drive charging LED.

openemc-shared/src/lib.rs

@@ -212,6 +212,8 @@ pub enum BootReason {
     ///
     /// This prevents automatic start of user program.
     StartBootloader = 0xb014,
+    /// Power off system and go to standby mode when entering bootloader.
+    PowerOffBootloader = 0xb015,
     /// Boot caused by factory reset.
     ///
     /// This clears the backup domain and prevents automatic start of user program.
@@ -233,6 +235,7 @@ impl BootReason {
             v if v == Self::Restart as _ => "restart",
             v if v == Self::Reset as _ => "reset",
             v if v == Self::StartBootloader as _ => "start boot loader",
+            v if v == Self::PowerOffBootloader as _ => "power off in boot loader",
             v if v == Self::FactoryReset as _ => "factory reset",
             v if v == Self::WatchdogTimeout as _ => "watchdog timeout",
             _ => "",