diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 44126ae55a19..e0dc823c622a 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -1199,6 +1199,7 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
 	if (!vc4_hdmi)
 		return -ENOMEM;
 
+	dev_set_drvdata(dev, vc4_hdmi);
 	encoder = &vc4_hdmi->encoder.base.base;
 	vc4_hdmi->encoder.base.type = VC4_ENCODER_TYPE_HDMI0;
 	vc4_hdmi->pdev = pdev;
@@ -1361,7 +1362,28 @@ static void vc4_hdmi_unbind(struct device *dev, struct device *master,
 {
 	struct drm_device *drm = dev_get_drvdata(master);
 	struct vc4_dev *vc4 = drm->dev_private;
-	struct vc4_hdmi *vc4_hdmi = vc4->hdmi;
+	struct vc4_hdmi *vc4_hdmi;
+
+	/*
+	 * ASoC makes it a bit hard to retrieve a pointer to the
+	 * vc4_hdmi structure. Registering the card will overwrite our
+	 * device drvdata with a pointer to the snd_soc_card structure,
+	 * which can then be used to retrieve whatever drvdata we want
+	 * to associate.
+	 *
+	 * However, that doesn't fly in the case where we wouldn't
+	 * register an ASoC card (because of an old DT that is missing
+	 * the dmas properties for example), then the card isn't
+	 * registered and the device drvdata wouldn't be set.
+	 *
+	 * We can deal with both cases by making sure a snd_soc_card
+	 * pointer and a vc4_hdmi structure are pointing to the same
+	 * memory address, so we can treat them indistinctly without any
+	 * issue.
+	 */
+	BUILD_BUG_ON(offsetof(struct vc4_hdmi_audio, card) != 0);
+	BUILD_BUG_ON(offsetof(struct vc4_hdmi, audio) != 0);
+	vc4_hdmi = dev_get_drvdata(dev);
 
 	cec_unregister_adapter(vc4_hdmi->cec_adap);
 	vc4_hdmi_connector_destroy(&vc4_hdmi->connector.base);
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index 749a807cd1f3..d43462789450 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -53,13 +53,13 @@ struct vc4_hdmi_audio {
 
 /* General HDMI hardware state. */
 struct vc4_hdmi {
+	struct vc4_hdmi_audio audio;
+
 	struct platform_device *pdev;
 
 	struct vc4_hdmi_encoder encoder;
 	struct vc4_hdmi_connector connector;
 
-	struct vc4_hdmi_audio audio;
-
 	struct i2c_adapter *ddc;
 	void __iomem *hdmicore_regs;
 	void __iomem *hd_regs;