[PATCH 1/2] drm/bridge/lontium-lt9611uxc: fix waiting for EDID to become available

[Laurent Pinchart]

Hi Dmitry,

On Tue, Jan 05, 2021 at 08:20:39PM +0300, Dmitry Baryshkov wrote:
> Gracious ping for these two patches

I'm afraid I have very little time for DRM bridge maintenance at the
moment :-S Judging by the lack of replies, it seems the other
maintainers are also AWOL. We seem to have a shortage of maintainers for
this part of the subsystem.

> On Fri, 27 Nov 2020 at 12:23, Dmitry Baryshkov wrote:
> >
> > - Call wake_up() when EDID ready event is received to wake
> >   wait_event_interruptible_timeout()
> >
> > - Increase waiting timeout, reading EDID can take longer than 100ms, so
> >   let's be on a safe side.
> >
> > - Return NULL pointer from get_edid() callback rather than ERR_PTR()
> >   pointer, as DRM code does NULL checks rather than IS_ERR().
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
> > ---
> >  drivers/gpu/drm/bridge/lontium-lt9611uxc.c | 11 ++++++++---
> >  1 file changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/bridge/lontium-lt9611uxc.c b/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
> > index 0c98d27f84ac..b708700e182d 100644
> > --- a/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
> > +++ b/drivers/gpu/drm/bridge/lontium-lt9611uxc.c
> > @@ -145,8 +145,10 @@ static irqreturn_t lt9611uxc_irq_thread_handler(int irq, void *dev_id)
> >
> >         lt9611uxc_unlock(lt9611uxc);
> >
> > -       if (irq_status & BIT(0))
> > +       if (irq_status & BIT(0)) {
> >                 lt9611uxc->edid_read = !!(hpd_status & BIT(0));
> > +               wake_up_all(&lt9611uxc->wq);
> > +       }
> >
> >         if (irq_status & BIT(1)) {
> >                 if (lt9611uxc->connector.dev)
> > @@ -465,7 +467,7 @@ static enum drm_connector_status lt9611uxc_bridge_detect(struct drm_bridge *brid
> >  static int lt9611uxc_wait_for_edid(struct lt9611uxc *lt9611uxc)
> >  {
> >         return wait_event_interruptible_timeout(lt9611uxc->wq, lt9611uxc->edid_read,
> > -                       msecs_to_jiffies(100));
> > +                       msecs_to_jiffies(500));
> >  }
> >
> >  static int lt9611uxc_get_edid_block(void *data, u8 *buf, unsigned int block, size_t len)
> > @@ -503,7 +505,10 @@ static struct edid *lt9611uxc_bridge_get_edid(struct drm_bridge *bridge,
> >         ret = lt9611uxc_wait_for_edid(lt9611uxc);
> >         if (ret < 0) {
> >                 dev_err(lt9611uxc->dev, "wait for EDID failed: %d\n", ret);
> > -               return ERR_PTR(ret);
> > +               return NULL;
> > +       } else if (ret == 0) {
> > +               dev_err(lt9611uxc->dev, "wait for EDID timeout\n");
> > +               return NULL;
> >         }
> >
> >         return drm_do_get_edid(connector, lt9611uxc_get_edid_block, lt9611uxc);

-- 
Regards,

Laurent Pinchart