Re: [PATCH v4 3/3] USB: serial: cp210x: Workaround cp2108 GET_LINE_CTL bug

From: Johan Hovold
Date: Thu Oct 29 2015 - 03:19:30 EST


On Wed, Oct 28, 2015 at 09:51:26AM +0100, Johan Hovold wrote:
> On Tue, Oct 27, 2015 at 04:53:34PM -0500, Konstantin Shkolnyy wrote:
> > cp2108 GET_LINE_CTL returns the 16-bit value with the 2 bytes swapped.
> > However, SET_LINE_CTL functions properly. When the driver tries to modify
> > the register, it reads it, modifies some bits and writes back. Because the
> > read bytes were swapped, this often results in an invalid value to be
> > written. In turn, this causes cp2108 respond with a stall. The stall
> > sometimes doesn't clear properly and cp2108 starts responding to following
> > valid commands also with stalls, effectively failing.
> >
> > Signed-off-by: Konstantin Shkolnyy <konstantin.shkolnyy@xxxxxxxxx>

> I gave the series a really quick test on an cp2102-device I had lying
> around. I assume you verified the changes on some other older devices as
> well?

Did you test this series on the older device types as well?

Thanks,
Johan
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