Add GPIO-based RTS/DTR for Raspberry Pi

Author: bugadani

Cargo.lock

@@ -47,6 +47,7 @@ md5 = "0.7.0"
 miette = { version = "5.3.0", features = ["fancy"] }
 parse_int = "0.6.0"
 regex = "1.6.0"
+rppal = { version = "0.13", optional = true }
 serde = { version = "1.0.144", features = ["derive"] }
 serde-hex = "0.1.0"
 serde_json = "1.0.85"
@@ -61,3 +62,7 @@ thiserror = "1.0.34"
 toml = "0.5.9"
 update-informer = "0.5.0"
 xmas-elf = "0.8.0"
+
+[features]
+raspberry = ["dep:rppal"]
+default = []

espflash/Cargo.toml

@@ -146,6 +146,10 @@ pub fn connect(opts: &ConnectOpts, config: &Config) -> Result<Flasher> {
 
     let interface = Interface {
         serial_port: serial,
+        #[cfg(feature = "raspberry")]
+        rts: None,
+        #[cfg(feature = "raspberry")]
+        dtr: None,
     };
 
     Ok(Flasher::connect(

espflash/src/cli/mod.rs

@@ -1,16 +1,44 @@
 use serialport::SerialPort;
 
+#[cfg(feature = "raspberry")]
+use rppal::gpio::OutputPin;
+
 /// Wrapper around SerialPort where platform-specific modifications can be implemented.
 pub struct Interface {
     pub serial_port: Box<dyn SerialPort>,
+    #[cfg(feature = "raspberry")]
+    pub dtr: Option<OutputPin>,
+    #[cfg(feature = "raspberry")]
+    pub rts: Option<OutputPin>,
+}
+
+#[cfg(feature = "raspberry")]
+fn write_gpio(gpio: &mut OutputPin, level: bool) {
+    if pin_state {
+        gpio.set_high();
+    } else {
+        gpio.set_low();
+    }
 }
 
 impl Interface {
     pub fn write_data_terminal_ready(&mut self, pin_state: bool) -> serialport::Result<()> {
+        #[cfg(feature = "raspberry")]
+        if let Some(gpio) = self.dtr.as_mut() {
+            write_gpio(gpio, pin_state);
+            return Ok(());
+        }
+
         self.serial_port.write_data_terminal_ready(pin_state)
     }
 
     pub fn write_request_to_send(&mut self, pin_state: bool) -> serialport::Result<()> {
+        #[cfg(feature = "raspberry")]
+        if let Some(gpio) = self.rts.as_mut() {
+            write_gpio(gpio, pin_state);
+            return Ok(());
+        }
+
         self.serial_port.write_request_to_send(pin_state)
     }