On Thu, Jun 20, 2024 at 6:08 AM Dmitry Baryshkov
<dmitry.baryshkov@xxxxxxxxxx> wrote:
>
> On Thu, 20 Jun 2024 at 00:27, Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx> wrote:
> >
> > dpu_encoder_helper_phys_cleanup() calls the ctl ops without checking if
> > the ops are assigned causing discrepancy between its callers where the
> > checks are performed and the API itself which does not.
> >
> > Two approaches can be taken: either drop the checks even in the caller
> > OR add the checks even in dpu_encoder_helper_phys_cleanup().
> >
> > Adopt the latter approach as ctl ops are assigned revision based so may not
> > be always assigned.
>
> NAK, these calls are always assigned. Please make sure that they are
> documented as required and drop offending checks.
agreed, I'd rather see the obvious crash if somehow a required
callback didn't get set up, than a subtle/silent problem. It is
easier to debug that way.
BR,
-R
> >
> > Fixes: d7d0e73f7de3 ("drm/msm/dpu: introduce the dpu_encoder_phys_* for writeback")
> > Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > Closes: https://lore.kernel.org/all/464fbd84-0d1c-43c3-a40b-31656ac06456@moroto.mountain/T/
> > Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c | 9 ++++++---
> > 1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > index 708657598cce..7f7e6d4e974b 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c
> > @@ -2180,9 +2180,12 @@ void dpu_encoder_helper_phys_cleanup(struct dpu_encoder_phys *phys_enc)
> > if (ctl->ops.reset_intf_cfg)
> > ctl->ops.reset_intf_cfg(ctl, &intf_cfg);
> >
> > - ctl->ops.trigger_flush(ctl);
> > - ctl->ops.trigger_start(ctl);
> > - ctl->ops.clear_pending_flush(ctl);
> > + if (ctl->ops.trigger_flush)
> > + ctl->ops.trigger_flush(ctl);
> > + if (ctl->ops.trigger_start)
> > + ctl->ops.trigger_start(ctl);
> > + if (ctl->ops.clear_pending_flush)
> > + ctl->ops.clear_pending_flush(ctl);
> > }
> >
> > void dpu_encoder_helper_phys_setup_cdm(struct dpu_encoder_phys *phys_enc,
> > --
> > 2.44.0
> >
>
>
> --
> With best wishes
> Dmitry
