drm/vc4: hvs: Make the HVS bind first

We'll need to have the HVS binding before the HDMI controllers so that
we can check whether the firmware allows to run in 4kp60. Reorder a bit
the component list, and document the current constraints we're aware of.
Acked-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20210507150515.257424-8-maxime@cerno.tech

drivers/gpu/drm/vc4/vc4_drv.c

@@ -304,12 +304,21 @@ static const struct component_master_ops vc4_drm_ops = {
 	.unbind = vc4_drm_unbind,
 };
 
+/*
+ * This list determines the binding order of our components, and we have
+ * a few constraints:
+ *   - The TXP driver needs to be bound before the PixelValves (CRTC)
+ *     but after the HVS to set the possible_crtc field properly
+ *   - The HDMI driver needs to be bound after the HVS so that we can
+ *     lookup the HVS maximum core clock rate and figure out if we
+ *     support 4kp60 or not.
+ */
 static struct platform_driver *const component_drivers[] = {
+	&vc4_hvs_driver,
 	&vc4_hdmi_driver,
 	&vc4_vec_driver,
 	&vc4_dpi_driver,
 	&vc4_dsi_driver,
-	&vc4_hvs_driver,
 	&vc4_txp_driver,
 	&vc4_crtc_driver,
 	&vc4_v3d_driver,