On Tue, Oct 25, 2022 at 04:17:27PM +0000, Christian Bach wrote: > Ok > > I now tested the whole thing also with some of the v5.4.y kernels. Just to avoid misunderstandings I listed all my tests below: > > Kernel | Hash | Bug | Comment > Version | (date) | present | > ----------|--------------------------------------------|---------|-------------- > ----------|--------------------------------------------|---------|-------------- > v5.10-rc1 | 3650b228f83adda7e5ee532e2b90429c03f7b9ec | Yes | This kernel behaves exactly like 5.15.74 > | (25. October 2020) | | > ----------|--------------------------------------------|---------|-------------- > v5.4.219 | 35826e154ee014b64ccfa0d1f12d36b8f8a75939 | Yes | This kernel performs segnificantly worse in > | (19. October 2022) | worse | nagotiating with the USP-PD power-supply and > | | | even crashes about 50% of the tries. It then > | | | gets stuck in the ISR just as it does 100% > | | | of the time when connecting the USB-A to USB-C > | | | cable. (and even when disconnecting the cable) Thanks a lot for the detailed report. It would be great if you can send actual crash logs. Maybe that problem is fixable in v5.4.y. Can you also test v5.0 .. v5.3 ? Mainline would be best (not v5.0.x but v5.0) ? > I would love to send some kernel logs but I can not see any entry in dmesg. Can you instruct me how to get the corresponding kernel logs? > This won't be in dmesg; that would be way too noisy since it logs each state machine action. You should find the logs in /sys/debug/kernel/usb/tcpm-<index>. In older kernels it is just a file, in more recent kernels it is a directory with files in it. In really old kernels it is /sys/debug/kernel/tcpm/tcpm-<index>. If you don't immediately find the file(s), just search for files with "tcpm" in the name in /sys/kernel/debug. Hope this helps, Thanks, Guenter
