On Fri, Nov 01, 2019 at 01:17:35PM +1300, Jonathan Olds wrote: > Hi Johan, > > Thanks for that. > > I tested you patch out with the ch340g chip and it works fine for all > rates I tried. I used a logic analyzer and made the following > measurements... > > - wanted measured error > - 110 0.02% > * 256000 0.26% > - 576000 0.79% > * 921600 0.16% > * 1333333 0% > - 2000000 0% > - 3000000 0% > > The asterisk are the ones that are really bad with the current Linux > driver. Of the ones you that you mention my measurements match yours. > So that looks really good. Thanks for testing. Do you mind if I add a tested-by tag for you to the patch? > Yes the current Linux driver is a bit opaque. > > BTW I had trouble patching the ch341.c file using your patch. Using... > > ``` > wget > https://raw.githubusercontent.com/torvalds/linux/master/drivers/usb/serial/c > h341.c > patch ch341.c patch.diff > ``` > > where `patch.diff` was your patch I kept getting either > "patch: **** unexpected end of file in patch" or > "patch: **** malformed patch at line" depending what lines I changed. Not sure why that doesn't work, perhaps you just need to provide an appropriate "-p" option to strip the directory prefix? I suggest you use git directly instead. Clone Linus's repo at kernel.org, or use mine git://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial.git to get the latest USB serial changes. Then you can apply patches directly from a mailbox using git-am (or from a patch using git-apply). > However it was easy enough to manually apply your patch by hand and > that is what I did. Ok, good. Thanks again for testing. By the way, when communicating through the Linux mailing lists, try to respond inline as I've done here instead of top-posting. I'll try to look at the github repo you referred to and respin my patch today. Cheers, Johan
