Re: [PATCH v7 2/5] drm/scdc-helper: Add scdc_status debugfs entry

[Nicolas Frattaroli]

On Tuesday, 21 July 2026 14:41:42 Central European Summer Time Maxime Ripard wrote:
> On Tue, Jul 21, 2026 at 10:58:58AM +0200, Nicolas Frattaroli wrote:
> > SCDC provides status information on the current display link. At the
> > very least, it may be useful to expose this info through debugfs.
> >
> > Add a debugfs entry for it under the connector, which displays a few
> > more details parsed out of the SCDC registers. A new
> > drm_scdc_debugfs_init function can be called by the connector
> > implementation to initialise the debugfs file.
> >
> > Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@xxxxxxxxxxxxx>
> > ---
> >  drivers/gpu/drm/display/drm_scdc_helper.c | 184 ++++++++++++++++++++++++++++++
> >  include/drm/display/drm_scdc_helper.h     |  32 ++++++
> >  2 files changed, 216 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/display/drm_scdc_helper.c b/drivers/gpu/drm/display/drm_scdc_helper.c
> > +/**
> > + * drm_scdc_debugfs_init - Initialize scdc files in connector debugfs
> > + * @connector: pointer to &struct drm_connector to operate on
> > + * @root: debugfs &struct dentry for the debugfs root of @connector
> > + *
> > + * Creates SCDC-related debugfs files for @connector. Must be called after
> > + * @root is already created.
> > + */
> > +void drm_scdc_debugfs_init(struct drm_connector *connector, struct dentry *root)
> > +{
> > +	struct scdc_debugfs_priv *priv;
> > +
> > +	if (!root || !connector)
> > +		return;
> > +
> > +	priv = drmm_kzalloc(connector->dev, sizeof(*priv), GFP_KERNEL);
> > +	if (!priv)
> > +		return;
> > +
> > +	priv->connector = connector;
> 
> You need to take a reference to the connector pointer here with
> drm_connector_get()
> 
> With this fixed,
> Reviewed-by: Maxime Ripard <mripard@xxxxxxxxxx>
> 
> Maxime
> 

I think sashiko is onto something here with the memleak and the
entirety of the priv thing should go, which is fairly easy to do.
We don't reuse the state anymore anyways.

I'll then just pass the connector as the priv, which will be valid
for the lifetime of the debugfs entry. This means there's no cleanup.

Kind regards,
Nicolas Frattaroli