Sorry, I got distracted. I'm back now. Do you want me to test your 13 patch series? And what is that on top of?
Thanks On Fri, Dec 16, 2016 at 6:46 AM, Johan Hovold <jo...@kernel.org> wrote: > On Fri, Dec 16, 2016 at 01:19:05PM +0000, Aidan Thornton wrote: >> On Wed, Dec 14, 2016 at 3:28 PM, Johan Hovold <jo...@kernel.org> wrote: >> > The ch341 driver is based on reverse-engineering and contains some bits >> > which appear to be redundant and some which appear incompatible which >> > certain devices. >> > >> > Specifically, some CH340 devices seem unable to change the initial line >> > settings, which have so far been set to 5N1. Let's use a more reasonable >> > 8N1 default instead. >> > >> > Note that we also need to set the ENABLE_RX bit or receive will be >> > disabled after a reset during resume. >> >> Lost track a little of the testing, but I don't think you ever got >> Russel to test whether this worked using a driver that tried to change >> this through direct register writes which seem to be the only thing >> that has any effect on this strange hardware variant. Would be a >> little surprised if it didn't at this point - changing the line >> settings that way after initialization certainly works well enough to >> cause us all a headache. > > I believe he did test this against my usb-linus branch, which did not > have your recent changes. IIRC both removing that first LCR write and > changing it to 0xc3 worked, but maybe you're right and we only verified > removing it. > > In the same setup, changing the word size after successful > initialisation using direct register writes did not work however, and > the device appeared stuck at 5N1 or 8N1 depending on if the initial 0x50 > LCR write was left in or not. > >> If so, I suggest it might be clearer to drop this patch altogether in >> favour of patch 10 in the series, since the underlying problem is that >> setting the baudrate and LCR register didn't work and patch 10 fixes >> that. > > These two patches are definitely related, and I struggled a bit about > how to order things as I wanted to find a way to backport this minimal > change (from 5N1 to 8N1) without having to depend on the upcoming > changes in 4.10 (your changes) as that may be enough to enable support > in older kernels. > > I'll respin this, once we learn more about how those quirky devices > work. > > Thanks, > Johan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
