drm/rockchip: Check iommu itself instead of it's parent for device_is_available

When iommu itself is disabled in dts, we should
fallback to non-iommu buffer, check iommu parent
is meanless here.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210627084737.309163-1-andy.yan@rock-chips.com

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index 0ea0853..e4ebe60 100644 (file)
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -374,7 +374,7 @@ static int rockchip_drm_platform_of_probe(struct device *dev)
                }
 
                iommu = of_parse_phandle(port->parent, "iommus", 0);
-               if (!iommu || !of_device_is_available(iommu->parent)) {
+               if (!iommu || !of_device_is_available(iommu)) {
                        DRM_DEV_DEBUG(dev,
                                      "no iommu attached for %pOF, using non-iommu buffers\n",
                                      port->parent);