Re: [PATCH 06/13] USB: serial: ch341: fix initial line settings

[Johan Hovold <johan@kernel.org>]

On Fri, Dec 16, 2016 at 05:13:50PM +0100, Johan Hovold wrote:
> On Fri, Dec 16, 2016 at 08:04:18AM -0800, Russell Senior wrote:
> > 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?
> 
> Yes, please. It's against my usb-next branch.
> 
> I'll send you a couple of diagnostics patches as well shortly.

I ended up pushing a new branch, ch341 to my tree

	git://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial.git

which contains the full series as well as four debug patches (on top of
usb-next).

Could you first try and see if the series works with some register dumps
enabled:

	79e475a77796 dbg: ch341: add divisor and lcr debugging

If that works, could you try the next commit and see if all still works

	ee5a27b51e95 dbg: ch341: enable rx timer

Either way, could you also try the next commit which again tries to use
the init-command for all devices:

	a06b45d910e3 dbg: ch341: use init for all devices

and if that does not work, the final commit tries to use the init
command but always use the chip default LCR:

	6edc2830abe1 dbg: ch341: always use default LCR

As you know there are, at least two levels of "working" here

	1. Your device works and you can change baud rate, but you're
	   stuck with 8N1

	2. Changing LCR also works (e.g. switching back and forth
	   between say 5N1 and 8N1 also works).

When testing a new commit, always make sure to disconnect and reconnect
the device first.

Logs from all tests would be helpful (e.g. to see what effects the
various commands has on the registers).

Just let me know if you have any questions.

Thanks,
Johan