Re: [PATCH 15/33] drm/panel-simple: Fix dotclock for EDT ET035012DM6

Marco Felsch
2020-03-10T07:05:39Z

On 20-03-09 15:18, Ville Syrjälä wrote:
> On Fri, Mar 06, 2020 at 09:02:57AM +0100, Marco Felsch wrote:
> > On 20-03-03 16:52, Ville Syrjälä wrote:
> > > On Tue, Mar 03, 2020 at 08:33:20AM +0100, Marco Felsch wrote:
> > > > Hi Ville,
> > > >
> > > > On 20-03-02 22:34, Ville Syrjala wrote:
> > > > > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > > > >
> > > > > The currently listed dotclock disagrees with the currently
> > > > > listed vrefresh rate. Change the dotclock to match the vrefresh.
> > > > >
> > > > > Someone tell me which (if either) of the dotclock or vreresh is
> > > > > correct?
> > > >
> > > > Pls, check the datasheet which is linked within the comment. We hit the
> > > > vrefresh exactly if we are in SYNC MODE.
> > >
> > > It's too much work to start hunting datasheets for all these
> > > and figuring out what's going on in each case. Pls just
> > > inform me which way is correct if you know the details.
> >
> > How do you know that the clock is wrong if it is to much work? As I said
> > the clock is completely fine.
>
> htotal*vtotal*vrefresh != clock, so one or both are incorrect.

I checked the values using this equation:
clock / (htotal * vtotal) = vrefresh.

Regards,
Marco