Same issue under 5.4.0-89 kernel. Tested about 10 different boards, those ones based on ch340G does not work. Ones using ch340C or ch340K DOES work (mostly esp32 boards).
-- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-signed-hwe-5.11 in Ubuntu. https://bugs.launchpad.net/bugs/1946231 Title: esp8266 flashing stopped working with kernel 5.11.0-37-generic (ch341) Status in linux-signed-hwe-5.11 package in Ubuntu: Confirmed Bug description: the esp8266 development boards like wemos D1 mini have an integrated usb-uart converter which allows to flash/monitor/debug the esp8266 by usb cable and a tool called esptool on linux, which is either standalone (esptool package) or integrated into some IDE (platformio + visio) dmesg output: [ 46.614510] usbcore: registered new interface driver usbserial_generic [ 46.614523] usbserial: USB Serial support registered for generic [ 46.615912] usbcore: registered new interface driver ch341 [ 46.615925] usbserial: USB Serial support registered for ch341-uart [ 46.615938] ch341 1-9:1.0: ch341-uart converter detected [ 46.616332] usb 1-9: ch341-uart converter now attached to ttyUSB0 This convenient flashing method worked without issues up to kernel 5.11.0-36-generic and stopped working with 5.11.0-37-generic. The issue remains the same whether I use the esptool package or the version bundled with platformio, >> esptool --chip esp8266 --port /dev/ttyUSB0 --baud 115200 write_flash 0x0000 firmware.bin esptool.py v2.8 Serial port /dev/ttyUSB0 Connecting........_____....._____....._____....._____....._____....._____....._____ A fatal error occurred: Failed to connect to ESP8266: Timed out waiting for packet header The communication to the esp8266 still seems to work, but the flash process includes some additional DTR/RTS magic in the beginning to switch the esp into flash mode before transmitting the data. My impression is that this DTR/RTS process might be broken. I can flash an esp with an external UART (some dongle) and manually triggering the flash mode. I tried with several cables, esps, ... Booting the older kernel (5.11.0-36-generic) solves the issue ... There seems to be an update to the ch341 from kernel -36 to -37, but it is beyond my knowledge whether there is any connection. Description: Ubuntu 20.04.3 LTS Release: 20.04 ProblemType: Bug DistroRelease: Ubuntu 20.04 Package: linux-image-5.11.0-37-generic 5.11.0-37.41~20.04.2 ProcVersionSignature: Ubuntu 5.11.0-37.41~20.04.2-generic 5.11.22 Uname: Linux 5.11.0-37-generic x86_64 ApportVersion: 2.20.11-0ubuntu27.20 Architecture: amd64 CasperMD5CheckResult: skip CurrentDesktop: ubuntu:GNOME Date: Wed Oct 6 14:59:58 2021 InstallationDate: Installed on 2020-08-29 (403 days ago) InstallationMedia: Ubuntu 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731) SourcePackage: linux-signed-hwe-5.11 UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe-5.11/+bug/1946231/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp