Add interface config error

Author: bugadani

espflash/src/cli/mod.rs

@@ -136,6 +136,13 @@ pub fn connect(opts: &ConnectOpts, config: &Config) -> Result<Flasher> {
         .map_err(Error::from)
         .wrap_err_with(|| format!("Failed to open serial port {}", port_info.port_name))?;
 
+    #[cfg(feature = "raspberry")]
+    let mut gpios = rppal::Gpio::new().unwrap();
+
+    let interface = Interface::new(serial, opts, config)
+        .map_err(Error::from)
+        .wrap_err_with(|| format!("Failed to open serial port {}", port_info.port_name))?;
+
     // NOTE: since `get_serial_port_info` filters out all non-USB serial ports, we
     //       can just pretend the remaining types don't exist here.
     let port_info = match port_info.port_type {
@@ -152,10 +159,6 @@ pub fn connect(opts: &ConnectOpts, config: &Config) -> Result<Flasher> {
         }
         _ => unreachable!(),
     };
-    #[cfg(feature = "raspberry")]
-    let mut gpios = rppal::Gpio::new().unwrap();
-
-    let interface = Interface::new(serial, opts, config);
 
     Ok(Flasher::connect(
         interface,

espflash/src/error.rs

@@ -13,6 +13,7 @@ use crate::{
     elf::{FlashFrequency, FlashMode},
     flasher::FlashSize,
     image_format::ImageFormatId,
+    interface::SerialConfigError,
     partition_table::{CoreType, SubType, Type},
     Chip,
 };
@@ -91,6 +92,12 @@ https://github.com/espressif/esp32c3-direct-boot-example"
         help("Make sure the correct device is connected to the host system")
     )]
     SerialNotFound(String),
+    #[error("Incorrect serial port configuration")]
+    #[diagnostic(
+        code(espflash::serial_config),
+        help("Make sure you have specified the DTR signal if you are using an internal UART peripherial")
+    )]
+    SerialConfiguration(SerialConfigError),
     #[error("Canceled by user")]
     Canceled,
     #[error("The flash mode '{0}' is not valid")]
@@ -246,6 +253,12 @@ impl From<binread::Error> for Error {
     }
 }
 
+impl From<SerialConfigError> for Error {
+    fn from(err: SerialConfigError) -> Self {
+        Self::SerialConfiguration(err)
+    }
+}
+
 #[derive(Copy, Clone, Debug, Error, Diagnostic)]
 #[allow(dead_code)]
 #[repr(u8)]

espflash/src/interface.rs

@@ -7,6 +7,13 @@ use rppal::gpio::OutputPin;
 
 use crate::{cli::ConnectOpts, Config};
 
+#[derive(thiserror::Error, Debug)]
+pub enum SerialConfigError {
+    #[cfg(feature = "raspberry")]
+    #[error("You need to specify DTR when using an internal UART peripheral")]
+    MissingDtrForInternalUart,
+}
+
 /// Wrapper around SerialPort where platform-specific modifications can be implemented.
 pub struct Interface {
     pub serial_port: Box<dyn SerialPort>,
@@ -27,26 +34,30 @@ fn write_gpio(gpio: &mut OutputPin, level: bool) {
 
 impl Interface {
     #[cfg(feature = "raspberry")]
-    pub(crate) fn new(serial: Box<dyn SerialPort>, opts: &ConnectOpts, config: &Config) -> Self {
-        Self {
+    pub(crate) fn new(
+        serial: Box<dyn SerialPort>,
+        opts: &ConnectOpts,
+        config: &Config,
+    ) -> Result<Self, SerialConfigError> {
+        let rts_gpio = opts.rts.or(config.rts);
+        let dtr_gpio = opts.dtr.or(config.dtr);
+
+        Ok(Self {
             serial_port: serial,
-            rts: opts
-                .rts
-                .or(config.rts)
-                .map(|num| gpios.get(num).into_output()),
-
-            dtr: opts
-                .dtr
-                .or(config.dtr)
-                .map(|num| gpios.get(num).into_output()),
-        }
+            rts: rts_gpio.map(|num| gpios.get(num).into_output()),
+            dtr: dtr_gpio.map(|num| gpios.get(num).into_output()),
+        })
     }
 
     #[cfg(not(feature = "raspberry"))]
-    pub(crate) fn new(serial: Box<dyn SerialPort>, _opts: &ConnectOpts, _config: &Config) -> Self {
-        Self {
+    pub(crate) fn new(
+        serial: Box<dyn SerialPort>,
+        _opts: &ConnectOpts,
+        _config: &Config,
+    ) -> Result<Self, SerialConfigError> {
+        Ok(Self {
             serial_port: serial,
-        }
+        })
     }
 
     pub fn write_data_terminal_ready(&mut self, pin_state: bool) -> serialport::Result<()> {