Hi,
On Thu, Apr 21, 2022 at 9:00 AM Sankeerth Billakanti (QUIC)
<quic_sbillaka@xxxxxxxxxxx> wrote:
>
> >> + }
> >> +
> >> + /*
> >> + * External bridges are mandatory for eDP interfaces: one has to
> >> + * provide at least an eDP panel (which gets wrapped into panel-
> >bridge).
> >> + *
> >> + * For DisplayPort interfaces external bridges are optional, so
> >> + * silently ignore an error if one is not present (-ENODEV).
> >> + */
> >> + rc = dp_parser_find_next_bridge(dp_priv->parser);
> >> + if (rc && dp->is_edp) {
> >> + DRM_ERROR("eDP: cannot find the next bridge, rc = %d\n", rc);
> >> + goto edp_error;
> >> + } else if (rc && rc != -ENODEV) {
> >> + DRM_ERROR("DP: cannot find the next bridge, rc = %d\n", rc);
> >> + goto error;
> >> + }
> >
> >The above wouldn't be my favorite way of doing this. Instead, I would have
> >written:
> >
> > if (rc) {
> > DRM_ERROR("Cannot find the next bridge, rc = %d\n", rc);
> > goto err;
> > }
> > ...
> >
> >err:
> > if (dp->is_edp) {
> > disable_irq(...);
> > dp_display_host_phy_exit(...);
> > dp_display_host_deinit(...);
> > }
> > return rc;
> >
>
> If rc is ENODEV for DP, then we need to return 0. Shall I add like below ?
>
> err:
> if (dp->is_edp) {
> disable_irq(...);
> dp_display_host_phy_exit(...);
> dp_display_host_deinit(...);
> } else
> If (rc == -ENODEV)
> rc = 0;
> return rc;
I wouldn't. Then you're essentially going to "err" for a case that you
don't consider an error. I would instead have just handled it right
away.
rc = dp_parser_find_next_bridge(dp_priv->parser);
if (!dp->is_edp && rc == -ENODEV)
return 0;
This also is better IMO because it means you aren't assuming that
`dp_priv->parser->next_bridge` is "valid" (or at least NULL) after
dp_parser_find_next_bridge() returned an error.
-Doug
