[PATCH 2/6] drm/meson/dw-hdmi: convert to of_drm_find_and_get_bridge()

[Luca Ceresoli]

of_drm_find_bridge() is deprecated. Move to its replacement
of_drm_find_and_get_bridge() which gets a bridge reference, and ensure it
is put when done.

dw_hdmi->bridge is used only in dw_hdmi_top_thread_irq(), so in order to
avoid potential use-after-free ensure the irq is freed before putting the
dw_hdmi->bridge reference.

Signed-off-by: Luca Ceresoli <luca.ceresoli at bootlin.com>
---
 drivers/gpu/drm/meson/meson_dw_hdmi.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
index 0d7c68b29dff..fef1702acb14 100644
--- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
+++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
@@ -778,7 +778,7 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
 	if (IS_ERR(meson_dw_hdmi->hdmi))
 		return PTR_ERR(meson_dw_hdmi->hdmi);
 
-	meson_dw_hdmi->bridge = of_drm_find_bridge(pdev->dev.of_node);
+	meson_dw_hdmi->bridge = of_drm_find_and_get_bridge(pdev->dev.of_node);
 
 	DRM_DEBUG_DRIVER("HDMI controller initialized\n");
 
@@ -789,8 +789,12 @@ static void meson_dw_hdmi_unbind(struct device *dev, struct device *master,
 				   void *data)
 {
 	struct meson_dw_hdmi *meson_dw_hdmi = dev_get_drvdata(dev);
+	struct platform_device *pdev = to_platform_device(dev);
+	int irq = platform_get_irq(pdev, 0);
 
+	devm_free_irq(dev, irq, meson_dw_hdmi);
 	dw_hdmi_unbind(meson_dw_hdmi->hdmi);
+	drm_bridge_put(meson_dw_hdmi->bridge);
 }
 
 static const struct component_ops meson_dw_hdmi_ops = {

-- 
2.52.0