From: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
[ Upstream commit ef4e417eb3ec7fe657928f10ac1d2154d8a5fb38 ]
Though the unconditional enable/disable code is not a final solution,
we don't want to run into a NULL pointer situation when window group
doesn't link to its DC parent if the DC is disabled in Device Tree.
So this patch simply adds a check to make sure that window group has
a valid parent before running into tegra_windowgroup_enable/disable.
Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/tegra/hub.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/tegra/hub.c b/drivers/gpu/drm/tegra/hub.c
index bb97cad1eb699..b08ce1125996d 100644
--- a/drivers/gpu/drm/tegra/hub.c
+++ b/drivers/gpu/drm/tegra/hub.c
@@ -143,7 +143,9 @@ int tegra_display_hub_prepare(struct tegra_display_hub *hub)
for (i = 0; i < hub->soc->num_wgrps; i++) {
struct tegra_windowgroup *wgrp = &hub->wgrps[i];
- tegra_windowgroup_enable(wgrp);
+ /* Skip orphaned window group whose parent DC is disabled */
+ if (wgrp->parent)
+ tegra_windowgroup_enable(wgrp);
}
return 0;
@@ -160,7 +162,9 @@ void tegra_display_hub_cleanup(struct tegra_display_hub *hub)
for (i = 0; i < hub->soc->num_wgrps; i++) {
struct tegra_windowgroup *wgrp = &hub->wgrps[i];
- tegra_windowgroup_disable(wgrp);
+ /* Skip orphaned window group whose parent DC is disabled */
+ if (wgrp->parent)
+ tegra_windowgroup_disable(wgrp);
}
}
--
2.25.1
