Port, board and/or hardware

esp32s3, self-made board

MicroPython version

MicroPython v1.22.0-preview.975.g1897fe622.dirty on 2024-09-02; AntiGM (esp32s3 spiram octal) with ESP32S3

The board is self-made, which uses pin 19, 20 (USB D+/D-) to drive an ST7796 screen (i8080 parallel). I use an extra usb2serial bridge for downloading. See here.

Reproduction

To disable USB, I removed boards/sdkconfig.usb from SDKCONFIG_DEFAULTS and added the following.

CONFIG_USB_ENABLED=n
CONFIG_USB_CDC_ENABLED=n

CONFIG_TINYUSB_CDC_ENABLED=n
CONFIG_ESP_CONSOLE_USB_CDC=n
CONFIG_ESP_CONSOLE_USB_SERIAL_JTAG=n
CONFIG_USB_OTG_SUPPORTED=n

But this results in a failure of make BOARD=myboard.

Expected behaviour

You should be able to compile a firmware for esp32s3 with USB disabled.

Observed behaviour

usb.c complains that some symbols are missing, e.g., the following.

/Users/***/mcu/micropython/ports/esp32/usb.c:41:27: error: 'CONFIG_TINYUSB_CDC_RX_BUFSIZE' undeclared here (not in a function); did you mean 'CFG_TUD_CDC_RX_BUFSIZE'?
   41 | static uint8_t usb_rx_buf[CONFIG_TINYUSB_CDC_RX_BUFSIZE];
      |                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |                           CFG_TUD_CDC_RX_BUFSIZE

Additional Information

I first tested this on lv_micropython and succeeded in making a usable firmware which can drive the screen. Since lv_micropython is a very old fork of micropython and is based on esp-idf v4.4, I decided to try micropython directly in case someday esp-idf v4 is no longer supported. Then came this issue, as is also encountered by others: #15290, #11315.

I noticed a change in usb.c. In this commit, you changed CONFIG_USB_ENABLED to CONFIG_USB_OTG_SUPPORTED. However, this is always set to yes as long as your IDF_TARGET is set to esp32s3. Try this simple CMakeLists.txt.

cmake_minimum_required(VERSION 3.12)


# Define the output sdkconfig so it goes in the build directory.
set(SDKCONFIG ${CMAKE_BINARY_DIR}/sdkconfig)

# Specific options for IDF v5.2 and later
set(SDKCONFIG_IDF_VERSION_SPECIFIC "")
if (IDF_VERSION VERSION_GREATER_EQUAL "5.2.0")
    set(SDKCONFIG_IDF_VERSION_SPECIFIC boards/sdkconfig.idf52)
endif()

set(IDF_TARGET esp32s3)

# Include main IDF cmake file.
include($ENV{IDF_PATH}/tools/cmake/project.cmake)

# Define the project.
project(test)

Then cat sdkconfig|grep USB_OTG will show you:

CONFIG_SOC_USB_OTG_SUPPORTED=y
CONFIG_SOC_USB_OTG_PERIPH_NUM=1
CONFIG_ESP_ROM_USB_OTG_NUM=3
CONFIG_USB_OTG_SUPPORTED=y

Thus, you are unable to change it by sdkconfig.board because it only defines the default values. This explains #15290.

So my solution to this is to undef CONFIG_USB_OTG_SUPPORTED in usb.h

// ports/esp32/usb.h

#ifndef MICROPY_INCLUDED_ESP32_USB_H
#define MICROPY_INCLUDED_ESP32_USB_H

#define MICROPY_HW_USB_CDC_TX_TIMEOUT_MS (500)

void usb_init(void);
void usb_tx_strn(const char *str, size_t len);

#endif // MICROPY_INCLUDED_ESP32_USB_H

#undef CONFIG_USB_OTG_SUPPORTED
#define CONFIG_USB_OTG_SUPPORTED 0

I guess you have to go back to a configurable variant name.

Code of Conduct

Yes, I agree