Re: [PATCH] usb: typec: tcpm: Correct the PPS out_volt calculation

From: Greg KH
Date: Thu Jan 31 2019 - 03:01:05 EST


On Thu, Jan 31, 2019 at 09:31:25AM +0200, Heikki Krogerus wrote:
> On Wed, Jan 30, 2019 at 11:13:53AM +0800, Kyle Tso wrote:
> > When Sink negotiates PPS, the voltage range of selected PPS APDO might
> > not cover the previous voltage (out_volt). If the previous out_volt is
> > lower than the new min_volt, the output voltage in RDO might be set to
> > an invalid value. For instance, supposed that the previous voltage is
> > 5V, and the new voltage range in the APDO is 7V-12V. Then the output
> > voltage in the RDO should not be set to 5V which is lower than the
> > possible min_volt 7V.
> >
> > Fix this by choosing the maximal value between the previous voltage and
> > the new min_volt first. And ensure that this value will not exceed the
> > new max_volt. The new out_volt will fall within the new voltage range
> > while being the closest value compared to the previous out_volt.
> >
> > Signed-off-by: Kyle Tso <kyletso@xxxxxxxxxx>
>
> Fixes: c710d0bb76ff0 ("usb: typec: tcpm: Extend the matching rules on PPS APDO selection")
> Cc: stable...

No need for stable, as c710d0bb76ff ("usb: typec: tcpm: Extend the
matching rules on PPS APDO selection") only showed up in 5.0-rc1.

Note, no need for the extra digit on your sha1 listing, here's the
recommended way to show this:
git show -s --abbrev-commit --abbrev=12 --pretty=format:"%h (\"%s\")%n"

thanks,

greg k-h