drm/sun4i: Store TCON's device structure pointer

We will need to access TCON's struct device from outside of TCON's driver
bind function. Store it in our private structure.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

drivers/gpu/drm/sun4i/sun4i_tcon.c

@@ -446,6 +446,7 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master,
 	dev_set_drvdata(dev, tcon);
 	drv->tcon = tcon;
 	tcon->drm = drm;
+	tcon->dev = dev;
 
 	if (of_device_is_compatible(dev->of_node, "allwinner,sun5i-a13-tcon"))
 		tcon->has_mux = true;

drivers/gpu/drm/sun4i/sun4i_tcon.h

@@ -143,6 +143,7 @@
 #define SUN4I_TCON_MAX_CHANNELS		2
 
 struct sun4i_tcon {
+	struct device			*dev;
 	struct drm_device		*drm;
 	struct regmap			*regs;