cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred (IDFGH-12827)

[HDLA-BG]

Answers checklist.

• I have read the documentation ESP-IDF Programming Guide and the issue is not addressed there.
• I have updated my IDF branch (master or release) to the latest version and checked that the issue is present there.
• I have searched the issue tracker for a similar issue and not found a similar issue.

IDF version.

v5.0.1

Espressif SoC revision.

esp32s3

Operating System used.

Windows

How did you build your project?

Command line with idf.py

If you are using Windows, please specify command line type.

PowerShell

Development Kit.

esp32s3

Power Supply used.

External 5V

What is the expected behavior?

No errors when downloading file via Modem

What is the actual behavior?

A lot of errors printed in the log coming from cdc_acm

Steps to reproduce.

1. Connect to Internet via Modem using USB
2. Request OTA update
   ...

Debug Logs.

E (156034) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156075) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156255) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156387) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156391) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156392) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156393) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156393) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156394) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156395) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156397) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156403) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156405) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156508) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156510) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156511) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred
E (156511) cdc_acm: cdc_acm_host_data_tx_blocking(1183): Incorrect number of bytes transferred

More Information.

We are using ESPModem driver and Modem SIMCOM A7672
The modem is Connected via USB.
The connection is stable until we request OTA update using https server.
After file transfer is started cfc_acm starts sending "Incorrect number of bytes transferred" and continue doing it during whole download process.

The problem doesn't appear every time but it is pretty often.

[roma-jam]

Hi @HDLA-BG,

Thanks for reporting the issue.

Despite the printed error, the OTA firmware update finishes successfully? Or when errors appears, the the OTA firmware update process finishes with error as well?

[HDLA-BG]

Hi @roma-jam

OTA update finishes successfully.
But we are sending all the logs to our backend, so this looks weird during the analysis.

[roma-jam]

Hi @HDLA-BG ,

thanks for clarification, it is good to know that data is not corrupted during the transfer.

Meanwhile, the error should not be there.
Let me check some details and I will return back asap.

[HDLA-BG]

Hi @roma-jam,

Thank you very much, I am waiting for your response. :)

[radiotommy]

@HDLA-BG
I think we got the same issue. The problem is in usb_host_cdc_acm component under esp-usb repo.
I got it fixed and made a PR:
espressif/esp-usb#40

[HDLA-BG]

@radiotommy

This is great, thanks, I hope it'll be merged soon.