On Thu, Feb 10, 2022 at 07:41:22AM +0200, Dmytro Bagrii wrote: > On 09.02.22 16:18, Johan Hovold wrote: > > I don't remember all the details, but judging from a quick look it seems > > we're just waiting for someone to resend the revert with a proper > > explanation. > > > > It would be good if Jan-Niklas could chime in too and confirm if he's > > able to use the device in UART mode instead. > > I'd like to take a look at that keeyees device from original commit > message to see if it has EEPROM chip. I can hypothesize that some > manufacturer of a CH341-based programmer could use external configuration > EEPROM and mixed-up PID value. I haven't experiment with configuring > CH341A with EEPROM but suppose it's possible to burn any custom VID:PID > there. I don't think ch341 driver has to handle any of such custom > VID/PID, especially if it conflicts with an original VID/PID assigned by > chip manufacturer. In case of some peculiar devices it's possible to bind > custom VID:PID to the driver via sysfs. > > But it's just my hypothetical assumption how ch341-based device with PID > 5512 could work as UART in that case. > > I just checked if CH341 that i have can work as UART when configured as > I2C/SPI (PID 5512). I doesn't work: no output signal on TX pin, no > loopback echo when RX connected to self TX. Thanks for confirming. Johan
