Re: [PATCH] drm/panel-edp: Use ktime_get_boottime for delays

[Doug Anderson]

Hi,

On Fri, Nov 11, 2022 at 12:44 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> On Thu, Nov 10, 2022 at 1:51 PM Drew Davenport <ddavenport@xxxxxxxxxxxx> wrote:
> >
> > ktime_get is based on CLOCK_MONOTONIC which stops on suspend. On
> > suspend, the time that the panel was powerd off is recorded with
> > ktime_get, and on resume this time is compared to the current ktime_get
> > time to determine if the driver should wait for the panel to power down
> > completely before re-enabling it.
> >
> > Because we're using ktime_get, this delay doesn't account for the time
> > that the device is suspended, during which the power down delay may have
> > already elapsed.
> >
> > Change to use ktime_get_boottime throughout, which uses CLOCK_BOOTTIME
> > which does not stop when suspended. This ensures that the resume path
> > will not be delayed if the power off delay has already been met while
> > the device is suspended.
> >
> > Signed-off-by: Drew Davenport <ddavenport@xxxxxxxxxxxx>
> >
> > ---
> >
> >  drivers/gpu/drm/panel/panel-edp.c | 8 ++++----
> >  1 file changed, 4 insertions(+), 4 deletions(-)
>
> Nice!
>
> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
>
> My plan will be to land this to drm-misc-next early next week (Tuesday
> maybe?) unless someone has any objections.
>
> BTW: any chance you'd be willing to post against two similar drivers:
> panel-simple.c and panel-samsung-atna33xc20.c? They have nearly the
> same code (and, yes, these drivers are purposely copies since there
> was overall consensus that having one giant panel driver to handle all
> possible panels was getting far too confusing)

Breadcrumbs: after discussion, this got vacuumed up into a larger
series and is now at:

https://lore.kernel.org/r/20221117133655.2.Iebd9f79aba0a62015fd2383fe6986c2d6fe12cfd@changeid