Expose the USB-serial-jtag peripheral (#503)

* add BlockingIoDriver to make stdin/out/err calls blocking

* gate sys imports

* use at least enumset 1.1.4 to make EnumSet::empty() a const fn

* add missing trait impl

* fix wrong macro usage

* fix macro

* Remove all VFS code in prep to move it to esp_idf_svc::io::vfs

---------

Co-authored-by: Frederick Vollbrecht <[email protected]>

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Breaking
 - Make the UART config to ESP-IDF  C config reusable outside the UART driver (for OpenThread)
 - Re-use the SPI config struct of the SPI driver (for OpenThread)
+- Add a `usb_serial` peripheral to the `Peripherals` struct for MCUs that do support the USB-serial-jtag peripheral (#503)
 
 ### Added
 - Docs: Add some docstrings for ADC module. (#455)

src/lib.rs

@@ -74,6 +74,8 @@ pub mod uart;
 ))]
 pub mod ulp;
 pub mod units;
+#[cfg(esp_idf_soc_usb_serial_jtag_supported)]
+pub mod usb_serial;
 
 // This is used to create `embedded_hal` compatible error structs
 // that preserve original `EspError`.

src/peripherals.rs

@@ -31,6 +31,8 @@ use crate::uart;
     esp_idf_comp_ulp_enabled
 ))]
 use crate::ulp;
+#[cfg(esp_idf_soc_usb_serial_jtag_supported)]
+use crate::usb_serial;
 
 pub struct Peripherals {
     pub pins: gpio::Pins,
@@ -106,6 +108,8 @@ pub struct Peripherals {
         any(esp_idf_version_major = "4", esp_idf_version = "5.0")
     ))]
     pub twdt: watchdog::TWDT,
+    #[cfg(esp_idf_soc_usb_serial_jtag_supported)]
+    pub usb_serial: usb_serial::USB_SERIAL,
 }
 
 static TAKEN: core::sync::atomic::AtomicBool = core::sync::atomic::AtomicBool::new(false);
@@ -208,6 +212,8 @@ impl Peripherals {
                 any(esp_idf_version_major = "4", esp_idf_version = "5.0")
             ))]
             twdt: watchdog::TWDT::new(),
+            #[cfg(esp_idf_soc_usb_serial_jtag_supported)]
+            usb_serial: usb_serial::USB_SERIAL::new(),
         }
     }
 }

src/usb_serial.rs

@@ -0,0 +1,19 @@
+#![allow(non_camel_case_types)]
+//! USB Serial / JTAG peripheral
+//!
+//! Communication through a virtualized UART-like USB-CDC interface.
+//!
+//! By default, `println!` and `log!` output will be redirected to it if no UART
+//! connection is established to a HOST PC. The peripheral is initialized at startup
+//! and is using the ESP console slot 2 by default.
+//!
+//! ESP console slot 2 cannot be used to read from the HOST, only writing is supported.
+//! If reading from the HOST is necessary, reconfigure the ESP console by setting
+//! the following into your projects sdkconfig.default file:
+//! ```
+//! CONFIG_ESP_CONSOLE_USB_SERIAL_JTAG=y
+//! ```
+
+// TODO: impl usb_serial driver
+
+crate::impl_peripheral!(USB_SERIAL);