linux-kernel - Re: [PATCH 2/4] drm/dp_mst: Reformat drm_dp_check_act

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Message-ID: <bb25bdd85b0dba09292923e448447dec15994768.camel@redhat.com>
Date:   Mon, 06 Apr 2020 18:11:44 -0400
From:   Lyude Paul <lyude@...hat.com>
To:     Sean Paul <sean@...rly.run>
Cc:     dri-devel <dri-devel@...ts.freedesktop.org>,
        stable <stable@...r.kernel.org>,
        Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Maxime Ripard <mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        Dave Airlie <airlied@...hat.com>,
        Todd Previte <tprevite@...il.com>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 2/4] drm/dp_mst: Reformat drm_dp_check_act_status() a bit

On Mon, 2020-04-06 at 15:23 -0400, Sean Paul wrote:
> On Fri, Apr 3, 2020 at 4:08 PM Lyude Paul <lyude@...hat.com> wrote:
> > Just add a bit more line wrapping, get rid of some extraneous
> > whitespace, remove an unneeded goto label, and move around some variable
> > declarations. No functional changes here.
> > 
> > Signed-off-by: Lyude Paul <lyude@...hat.com>
> > [this isn't a fix, but it's needed for the fix that comes after this]
> > Fixes: ad7f8a1f9ced ("drm/helper: add Displayport multi-stream helper
> > (v0.6)")
> > Cc: Sean Paul <sean@...rly.run>
> > Cc: <stable@...r.kernel.org> # v3.17+
> > ---
> >  drivers/gpu/drm/drm_dp_mst_topology.c | 22 ++++++++++------------
> >  1 file changed, 10 insertions(+), 12 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c
> > b/drivers/gpu/drm/drm_dp_mst_topology.c
> > index 2b9ce965f044..7aaf184a2e5f 100644
> > --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> > +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> > @@ -4473,33 +4473,31 @@ static int drm_dp_dpcd_write_payload(struct
> > drm_dp_mst_topology_mgr *mgr,
> >   */
> >  int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr)
> >  {
> > +       int count = 0, ret;
> >         u8 status;
> > -       int ret;
> > -       int count = 0;
> > 
> >         do {
> > -               ret = drm_dp_dpcd_readb(mgr->aux,
> > DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);
> > -
> > +               ret = drm_dp_dpcd_readb(mgr->aux,
> > +                                       DP_PAYLOAD_TABLE_UPDATE_STATUS,
> > +                                       &status);
> >                 if (ret < 0) {
> > -                       DRM_DEBUG_KMS("failed to read payload table status
> > %d\n", ret);
> > -                       goto fail;
> > +                       DRM_DEBUG_KMS("failed to read payload table status
> > %d\n",
> > +                                     ret);
> > +                       return ret;
> >                 }
> > 
> >                 if (status & DP_PAYLOAD_ACT_HANDLED)
> >                         break;
> >                 count++;
> >                 udelay(100);
> > -
> >         } while (count < 30);
> > 
> >         if (!(status & DP_PAYLOAD_ACT_HANDLED)) {
> > -               DRM_DEBUG_KMS("failed to get ACT bit %d after %d
> > retries\n", status, count);
> > -               ret = -EINVAL;
> > -               goto fail;
> > +               DRM_DEBUG_KMS("failed to get ACT bit %d after %d
> > retries\n",
> 
> Should we print status in base16 here?

jfyi - I realized we don't actually need to do this, because we do this in the
next patch whoops. Just figured I'd point that out

> 
> Otherwise:
> 
> Reviewed-by: Sean Paul <sean@...rly.run>
> 
> > +                             status, count);
> > +               return -EINVAL;
> >         }
> >         return 0;
> > -fail:
> > -       return ret;
> >  }
> >  EXPORT_SYMBOL(drm_dp_check_act_status);
> > 
> > --
> > 2.25.1
> > 
-- 
Cheers,
	Lyude Paul (she/her)
	Associate Software Engineer at Red Hat